Technical Field The invention concerns the technical sector of installations for the distribution of meals in premises used for public eating, be they restaurants, refectories or vehicles.

Substantially the invention is directed to a more practical and intelligent quality and lifestyle, also for every day, given the typical stress of advanced modern society. Associated with other products, such as for example a means for practical mobility in town, this invention contributes to define the lifestyle of a user figure that cares for himself and for which time constitutes an important resource.

Background Art The problems of rooms used for public eating in quickly serving all the guests are known, which is difficult even when using a high number of waiters who would have in any case a high cost but who cannot always work simultaneously as they would obstruct each other.

To avoid these drawbacks, some installations have been designed that allow to distribute the meals to the tables, which however have important drawbacks.

In particular the patents US992672, US1314965 and other similar ones are known, which although they provide trolleys that shift from the zone of the kitchen to the tables and vice versa delivering the ordered food, do not offer any stability guarantee for the conveyer trolley and, which is worst, the trolley is always visible and not disappearing, so it encumbers the room.

Disclosure of invention The invention, besides presenting original and innovative solutions, settles the problem of safety against the free fall of a suspended load, also of considerable volume and also for surroundings where people have free access, by means of an air trolley endowed with a

system with combined screws (as the main essence of the invention) that makes it possible to lower and lift the load in absolute safety, as a food-carrier and of considerable weight, without any connection to earth. This in order to realize rooms with a practical and welcoming look, not encumbered by columns or the like, for an effective free traffic as well as fast transformable for example into dance-halls, halls for meetings, or the like. The system with combined screws offers intrinsic safety as it is endowed with propellers with spontaneous both static and dynamic irreversibility and because all the other transmission members of the air trolley are placed upstream of its system with combined screws. This system with combined screws thus serves the load with absolute reliability and consequently obviates to solutions with cables, cylinders, articulated parallelograms, connections to earth, or the like, which are to be found in the patents known so far. In the invention the necessary runs for the load, as a food-carrier, aboard an air trolley (combined unscrewings for the descent, combined screwings for rising) happen through the contemporary action of the abovementioned screw threads and thus require reduced times though having screws equipped with propellers inclined with a certain spontaneous static and dynamic irreversibility (Figs. 5 ; 6; 39; 36). Every descent of the system with combined screws, although equipped with a load, interferes neither with the space occupied by the guests, be they sitting or standing in their respective places at the table or walking around freely in the public eating place, nor with the space occupied by kitchen staff.

For an actual free traffic the beams of the main air structure, for supporting the air tracks and the related decorative carter, are engaged each directly to the external ends (keying or support in order not to hinder the thermal expansions) of posts adjacent to the walls of the public eating place. The main beams, with a long span as they are joined with aerial joints to form a good closed air structure, are moreover indirectly supported (only for large spans) by columns that, placed opportunely in a line and eventually equipped with a connection able not

to hinder the thermal expansions, allow free traffic in the public eating place and in the kitchen room.

The invention provides one or more closed circuit air tracks, all for one way traffic for a higher traffic density, for the transfer on aerial trolleys, at least one for each air track, of food or the like loaded on equipment made safe.

The installation can be equipped later with longer air tracks and still be equipped with the same number of aerial trolleys but without considerably increasing the waiting times. It is furthermore possible to endow the installation, even later, with more aerial trolleys.

Each air track 101 (lOlA) Figs. 4; 3 is decoratively masked in the public eating place by carters 17 Fig. 3 equipped with removable passages (view A) with automatic opening and closing, relocatable according to the various positions that the tables can assume for a new lay-out. These automatic passages, each managed by two semi-discs 16 View A with central half hole, they operate in three positions: the first completely open that allows the passing of the load, the second that shuts the passage leaving however space to the extended system with combined screws of the air trolley and the third that completely closes the passage closing down also the hole (semi-discs 16 partially superimposed). These automatised passages 16 are necessary for the descent and lifting an equipment that delivers the service to the table and consequently open automatically to allow the passing down of this equipment (as a food- carrier), close automatically (when the equipment has passed by) up to the system with combined screws of the air trolley for protecting the table underneath, open automatically to allow the passing upwards of the equipment itself and close completely when the equipment has entered again the carter 17 Fig. 3 of the air track. The tables of the public eating place are anchored to the floor with removably fixed seats and therefore are relocatable for a new lay- out.

Every air device is formed by an air trolley and by an equipment 91 (Figs. 25; 27 or Figs. 59; 61 ; 62), as a food-carrier, with three or possibly more food-carrier levels 91A Fig. 36

each with four compartments for thus up to twelve or more guests for each run of an equipment. Every food-carrier plane 91A of the equipment can form a closed chamber with the related couple of housings (removable) of perimeter masking 91B Figs. 36 ; 25 and with the contiguous plane and moreover benefits from a transparent perimeter lathe as a border for preventing the food, or the like, from falling. Each food-carrier floor 91A thus offers four different compartments VA Fig. 27, one for each guest, hideable from the related couple of perimeter housing 91B Fig. 25 which consists of two independent revolving housings, equipped with handles, each three-quarter of a turn wide in order to show to the guests only one compartment at a time for each food-carrier plane. As an alternative to such couples of perimeter housings 91B for hiding, to be closed by hand, thus chamber of the compartments of the relative food-carrier plane not closed automatically, every compartment VA Fig. 61 of the equipment has instead an automatically closed chamber if equipped with a proper circular door (housing) K Figs. 61 ; 62; Fig. 71 wide about a quarter of a turn and with automatic return by means of a spring M Fig. 62. In tins case opportune correspondences between the compartments VA Fig. 61 of the equipment and the places to be served at the tables (up to four for each lowering) allow each guest of the same lowering to pick up his food at the same time.

The coupling 80; 48 Figs. 36; 17; 18 that supports an equipment to the terminal 71 Fig. 36 of the system with combined screws of an air trolley is stable and sure and benefits from the door-lock 91C Figs. 63 which, subject to a key CH and equipped with a cam PA Figs. 63; 64, is placed on the equipment in order to ensure the safety of this equipment on board also against ill-willed people that, operating together, though with extreme difficulty, could manage to uncouple this equipment from the terminal and use it as blunt instrument.

The safety and the reliability of the air transfer of the equipment and of its content are warranted for everything described above as well as disclosed in the included drawings and therefore the customary free movement of the people in the respective places is admissible.

At each coupling station and each uncoupling station the invention provides a lifting tool, see Figs. 6; 43 or 65-71, placed in a fixed part, for the easy and fast coupling and uncoupling of an equipment to the and from the system with combined screws of an air trolley. As an alternative it is possible to employ the same lifting tool for each air track both for uncoupling and coupling one equipment at a time. Every semiautomatic coupling and uncoupling tool allows one only operator to easily handle and manage the loading and detachment on and from an air trolley of one equipment at a time, which even unloaded has a considerable weight. The uncoupled equipment rests on the rails or on the tracks of the floating structure of the lifting tool (uncoupling station) to be then manually pushed on the rails of the kitchen room.

Each transfer air trolley 61+65 (Fig. 39 or Fig. 51) moreover has an automatic mechanical release and grip element (a scissor plier or a spike lever) from and to the towing belt (either a cog belt with double toothing or a triple sprocket chain), with closed circuit, that runs along the air track. These releases and grips from and to the towing belt happen in the public eating place at each service at the table and in the kitchen at the uncoupling and coupling stations 7A; 7B; 7C; 7D Fig. 4, thus avoiding the stop of the towing belt when air trolleys are at a short stop for services while other air trolleys are approaching.

The invention, original and innovative, thus goes beyond everything described above and disclosed by the concepts that the patents known so far inform, above all thanks to its main essence (the system with combined screws of each air trolley).

The installation is managed by means of programs and subprograms, among which that very flexible one that manages the flow of the dishes for example with the FIFO criterion (First-In First-Out), or the like, elaborating all the data concerning the orders of the guests, each of them already easily sitting at his place at the table and having available, on the small mobile terminal 13 Fig. 4 available at the tables every four places, very detailed displays of the menu, assisted by menu on paper, and waiting for a short time for the food-carrier

equipment to sink and to offer him the ordered food'within hand's reach' (also in following phases). Such a management of information moreover allows the timely stocking up of the deposits, and each small mobile terminal 13 thus presents to the guests automatically updated menus in relation both to the availability of the ingredients in the kitchen and to the needs of the personnel. Every guest thus chooses the respective dishes by means of the above- mentioned tiny mobile terminal 13 available at the tables every four places and then sends out the order with the act of the payment, carried out with a badge or the like, through the terminal that highlights the partial and total costs for the food, also during the choice. The invention is thus also suitable for autonomous handicapped persons in a wheelchair if, by means of the tiny mobile terminal at the table, they communicate to the kitchen to put the respective food, or the like, on the lower plane of the equipment. Each room terminal 13 (if necessary'wireless') has a special key in order to command the rise of the equipment, and as a descent can serve up to four guests, thus four impulses are necessary (as an alternative a special push-button is provided, if necessary'wireless'or the like). The guest thus enters the public eating place, purchases a card for the payment at a vending machine 9, sits down at a table, chooses his meal, sends out the respective order with the payment through the terminal 13, waits for a short time, takes his food from his place at the table, consumes it, withdraws the rest of its card from a vending machine 9 and leaves.

If one wants to reduce the cost of the total installation considerably, it is possible to adopt, instead of the above-mentioned terminations 13 Fig. 4, leaflets showing the menu of the day and on which each guest can mark the selected food. The person who collects the used crockery and cutlery will, against the payment, collect the compiled forms and carry them to the kitchen.

The invention also allows the guest to avoid the queues (self-service) for the withdrawal of the food, which in fact he receives at his place at the table, as well as to be able to limit his stay in the public eating place to the time just necessary for eating and drinking. The public

eating place thus does not have noteworthy queues not even in peak hours and can take up a quite larger flow of guests, above all as regards traditional premises, which moreover are burdened by higher staff costs, which the invention cuts down significantly.

The profitability of the local is thus increased, with short or mid-term amortization of the installation. The invention results particularly convenient for middle-sized, large or very large public eating places.

This invention also allows considerable flexibility concerning the management of the orders which, besides being digited at the table by the guests, can be booked from outside for example by buying a ticket for sports events, cultural, or the like, or for other needs of the guests concerning the transmitted menus available at the sales points. The guest who has booked thus already knows the lapse of time for which his place at the table and his order are valid and at his arrival can immediately ask, by means of the tiny mobile terminal at the table or (the very economic alternative) a waiter, for his meal to be sent.

The installation provides a kitchen (Fig. 4) or more kitchens for very large public eating places.

The kitchen is equipped, for each track, at the uncoupling station, with a lifting tool, disclosed in Figs. 6 ; 43 or 65-71, for the fast removal of the equipment on board from an air trolley, and at the coupling station, with a tool, the same as the previous one, for the fast loading of a ready food-carrier equipment on an air trolley.

The uncoupling stations and the coupling stations 7A; 7B; 7C; 7D Fig. 4, placed in the kitchen one for each air track 101 (101A) Figs. 4; 3, they are connected both because each equipment can be moved on binaries connected by rotatory switches 1A Fig. 4 and because each return air trolley, freed from the equipment, can be moved, on the same air track, from the uncoupling station (7A or 7B) to the related coupling station (7D or 7C) waiting to receive a ready food-carrier equipment for that air track.

Returning in the kitchen (uncoupling station 7A or 7B Fig. 4) the air trolley disengages automatically from the towing belt (the cog belt with double toothing 96 Fig. 33 or the triple sprocket chain 266 Fig. 55) of the air track and is at once placed in stop. The operator, by a special push-button, commands the descent of the system with combined screws, see Figs. 5 ; 6; 39; 36 or 51; 71, of the air trolley that is in stop in order to uncouple the return equipment by means of the lifting tool, see Figs. 43; 71. The operator then manoeuvres for uncoupling the equipment according to the description in Figs. 17 ; 18 and then, by another push-button interlocked with a proximity sensor (89 Figs. 43; 71) phased to the releasing rabbet, commands the lifting of the system with combined screws of the air trolley as the equipment is to pass, pushed manually, from the rails or from the tracks of this tool (floating structure) to the rails of the kitchen. The following automatic re-engagement of the air trolley to the air track towing belt still occurs at the uncoupling station (7A or 7B Fig. 4) at the end of the lifting stroke of this system with combined screws (now freed from the equipment).

At the coupling station (7C or 7D Fig. 4) this air trolley disengages automatically from the air track towing belt and is at once placed in stop. The operator manually pushes a ready food-carrier equipment on the rails or on the tracks of the tool (floating structure) and then, by a special push-button, commands the descent of the system with combined screws, see Figs. 5 ; 6; 39; 36 or 51; 71, of this air trolley that was in stop in order to couple the equipment. The operator then manoeuvres for coupling the equipment according to the description in Figs. 17 ; 18 and then, by another push-button interlocked with a proximity sensor phased with the coupling rabbet, commands the lifting of the system with combined screws of the air trolley which in this way hooks the equipment. The following automatic re- engagement of the air trolley to the air track towing belt still occurs at the coupling station (7C or 7D Fig. 4) at the end of the lifting stroke of this system with combined screws (now charged with the equipment).

The access of an food-carrier equipment to a waiting air trolley (coupling station) on the predestined air track is subordinated to a sight check carried out by the operator on the plate of destinations TA Figs. 31 ; 53 related to that equipment or on a any invoice list FA Figs. 25; 59 of the equipment.

The invoice list FA Figs. 25; 59 of each order, as it identifies the respective room, must be placed with the air track code, with the code of the table and with the code of the place at the table, all well visible, within the suitable seat, fixed in a removable way at the equipment on the edge of the relative food-carrier plane near the respective room.

In the kitchen, at the uncoupling and coupling stations (7A; 7B; 7C; 7D Fig. 4), the descent of the system with combined screws of the air trolley in stop is commanded by the operator pushing the respective descent push-button. In the kitchen, respectively at the uncoupling and coupling stations, the lifting of the system with combined screws of this air trolley is commanded by the operator by pushing the respective lifting push-button interlocked with the consent of the sensor (uncoupling or coupling) that checks the phasing of this equipment.

Every service at the tables (public eating place) begins with the automatic disengagement of the gripping element of the air trolley (a scissor plier or a spike lever) from the towing belt (either a cog belt with double tootling or a triple sprocket chain) of the air track and ends with the automatic re-engagement of this gripping element to the towing belt.

Each air trolley can thus disengage and engage again automatically from and to the towing belt, not only in the kitchen at the uncoupling and coupling stations but also in the public eating place at the tables to be served.

All the possible descents of a same air track are each equipped with an electronic reading threshold for bar codes or with an electromechanical detection threshold with sensors in order to intercept the trolleys of interest.

While the electronic reading thresholds 274 Fig. 51 for bar codes are intended to interface the plate of destinations TA Figs. 51 ; 31; 53 of the incoming air trolley, which bears the code of the air track as well as the codes (also bar codes) of each table to be served, the electromechanical detection thresholds with sensors 111F ; 111F'Fig. 58 are intended to interface the cursors 111C ; 111C'of destination of the incoming air trolley. The plate TA of destinations, printed according to the program that manages the orders run by run, is however still necessary as it tells the operator at the coupling station how to set out the destination cursors 111C ; 111C'of the outward bound air trolley.

An air trolley running on a track with electronic reading thresholds will stop automatically at each positive match between its plate TA Figs. 31 ; 53; 51 of destinations and each electronic reading threshold 274 Fig. 51 situated along the air track, namely in the public eating place at the tables to be served and in the kitchen (where every reading results positive) at the uncoupling station and at the coupling station (where this no longer valid plate is replaced). The plate of destinations TA Fig. 31 is placed in the suitable seat, fixed to the external pipe 117 Fig. 36 of the protection (not rotating) of the system with combined screws 69; 68; 31; 66; 35 Fig. 39 of the air trolley, when this system with combined screws has gone down for loading a new equipment (coupling station) and this seat is therefore easily accessible to the operator who consequently withdraws the returned plate TA and inserts the new plate TA for the run of the outward bound equipment. If the air trolley is without the protection 113; 114; 117 Fig. 36 for its system with combined screws, in this case for the plate of destinations TA Fig. 53 a suitable seat fixed on the external pipe 35 is provided (not rotating and at full descent) of this system with combined screws.

The air trolley then runs along all the air track in the public eating place and the plate TA Figs. 31; 53 that identifies the stops of the equipment interfaces one by one all the electronic reading thresholds (for bar codes) placed at the tables while the air trolley engages with those power supply contacts placed in a fixed part (correctly insulated and with self-

cleaning sliding contacts, in silver gilt for a considerable long life) necessary for the descents and rises of its system with combined screws, which at the terminal 71 Figs. 17 ; 18 bears the equipment. Each positive interfacing between the plate TA Figs. 31 ; 53; 51 of destinations and the electronic reading threshold 274 Fig. 51 placed in a fixed part near the relative table produces the stop of the air trolley and therefore, in the public eating place, the automatic descent of the equipment. In the public eating place the descent of an food-carrier equipment 91 Figs. 25; 27 or Figs. 59; 61 begins at the complete opening of the passing of air track 16 Fig. 3 View A, whereat the system with combined screws of the air trolley in stop descends automatically until it puts the equipment on board'within hand's reach'of the guests.

The system with combined screws (Figs. 5 ; 6; 39; 36 or 51; 71), after having served with automatic descent (combined unscrewings) the first up to four guests, will have to be elevated (combined screwings), in order not to disturb the contiguous as well as the other guests, commanded by means of the special signal sent by each potential guest with a special key of the tiny mobile terminal, if necessary'wireless', 13 Fig. 4 (or with a special push- button, also this if necessary'wireless'or the like) available at the table every four places. As a descent can serve up to four guests, four impulses are necessary to command the rise of the equipment. This rise goes up to the level of the air tracks in order to shift there automatically, proceeding until the next service or in order to return into the kitchen.

It is possible to reduce the cost of the total installation by using, for the comparisons of descents, rather than electronic reading thresholds for bar codes, electromechanical detection thresholds with sensors. In the public eating place these electromechanical detection thresholds, each placed partly fixed 111E ; HE'Fig. 58 to guard the relative table, each consist of a pair of sensors 111F ; 111F'intended for detecting the air trolleys to be intercepted in order to lower the equipment on board. In the kitchen these electromechanical detection thresholds, placed in a fixed part to guard the uncoupling station and the coupling station of each air track, are intended each to intercept in any case the incoming air trolleys

and so consist of a sensors comb 111F that covers all the positions reserved to the cursor 111C of the sector of the incoming air trolley.

Where the solution with backing electromechanical thresholds is adopted, subdividing ideally in the public eating place an air track in sectors (for example in 5 sectors) each with a maximum number of tables (for example 12 tables) and each table being able to host up to 4 guests, every track can cover up to 5 X 12 = 60 tables and thus up to 60 X 4 = 240 seats. With such fitting out of the installation, an air trolley can however serve only one air track sector with its ongoing run because otherwise it would not be possible establish a valid correspondence between cursors and tables. At the uncoupling station (7A; 7B Fig. 4) and at the coupling station (7D; 7C) of each air track, the stop of the incoming air trolleys being required anyway, it is sufficient to put all the sectorial sensors 111F Fig. 58 (for the example 5) into a fixed part in order to detect the sectorial cursor 111C of the incoming air trolley anyway but not the sensors 111F'for the cursors 111C'of the tables, as in the kitchen the stop for uncoupling and the stop for coupling are compulsory. However it should be pointed out that the solution with electronic reading thresholds 274 Fig. 51 (bar codes) can cover a much higher number of tables as to the solution with electromechanical detection thresholds with sensors 111F ; 111F'Fig. 58 and that the solution with electronic thresholds admits tables placed everywhere along the track rather than belonging to only one sector for each run of the air trolley.

The option with electromechanical backing thresholds provides that each air trolley is equipped with two rulers 111B ; 111B'Fig. 58 made integral by means of half rings HID acting as a clamp on the external pipe 35 (also Fig. 53) of the system with combined screws in order to house snap cursors 111C ; 111C'each equipped with an index and to be positioned on behalf of the operator at the coupling station according to the destinations in the room (descents) requests to the equipment to be put aboard the air trolley. Where the air trolley is equipped with a protection 113; 114; 117 Fig. 36 for its system with combined screws, in this

case it is foreseen to block the two rulers 111B ; 111B'Fig. 58 on the external pipe 117 Fig. 31 (not rotating and at full descent) of the protection. These two rulers 111B ; 111B'Fig. 58 of the air trolley are thus equipped with imprints (identified with stamped figures) that should be assigned partly to the air track sectors and partly to the tables in the sector. The snap cursors 111C ; 111C'are each equipped with a suitable appendix as an index in order to engrave the imprint of interest, as well as with a spheric elastic presser for engaging such imprint. The operator at the coupling station can easily manage these cursors when the system with combined screws has gone down for receiving a new equipment, thus arranging them for the new run according to the indication by the plate TA of destinations (that he holds) related to the outward bound equipment.

In the public eating place each positive interfacing between such cursors 111C ; 111C' Fig. 58 of destination of the air trolley and a pair of sensors 111F ; 11F'placed in a fixed part on the same level as the air tracks as electromechanical detection threshold that guards the related descent determines the stop of this incoming air trolley which thus results disengaged from the towing belt and anchored in a fixed place. The descent of the food-carrier equipment on board begins at the complete opening of the passage of air track 16 Fig. 3 View to whereat the system with combined screws of the air trolley descends until it puts the equipment 91 Figs. 25; 27 or Figs. 59; 61'within hand's reach'of the guests. Every incoming air trolley at a descent of air track results in grip with (sliding) electric contacts at a fixed part, correctly insulated, self-cleaning and in silver gilt for a considerable long life.

Every air track is equipped with a flexible band (a cog belt 96 Fig. 33 with double toothing or a triple sprocket chain 266 Fig. 55) in order to tow the attached air trolleys, all with automatic engagement and release to and from this flexible band. The ratio-motor (managed by signals)'towing'the air track (97 Fig. 39 if track with belt and 255 Fig. 50 if track with chain) benefits from an accelerating ramp for the start and a decelerating ramp for the stop of the flexible band of the air track.

If a cog belt (with double toothing) armed with steel cables with high flexibility is used as air track towing belt, it results almost inextensible. This air track towing belt uses idle side gears 108A Fig. 40 (in Fig. 21 the figure is rotated) which are relocatable if need be, as they are mounted on plates equipped with buttonholes that on the air structure have frequent fixing holes.

The idle pulleys 108C Fig. 33 for the towing belt 96 are each placed on an elastic part (not shown in the drawing) in order to compensate the lengthening difference due to the thermal jump (winter/summer) between the air track 101 (to metal pipe) and the cog belt 96 which thus results correctly tensioned. The installation is thus valid also for not air-conditioned and very large rooms. The motor transmission that drives the cog belt 96 Fig. 39 towing the air track consists of the composite pulley 108+109 that, having roller bearings 108B, results idle (on a fixed part), of the motor cog belt 107 and of the driving pulley 95 in direct drive to the 'towing'ratio-motor 97. Being idle, the driven pulley 108+109 of this motor transmission engages a sufficient surrounding angle to drive the towing belt 96.

If a triple sprocket chain 266 Fig. 47 is used as air track towing belt, the air track does not need (for the rectilinear stretches) idle side gears but matched chain guide sections as well as (in the corners) idle gears 260A Fig. 55 assembled for engaging the opposite tracks of the sprocket chain rather than idle gears 108C Fig. 33 for a cog belt. As the triple chain 266 of the air track runs being vertical, for the rectilinear stretches of the air track it is necessary to add to this chain both a chain guide for the lowest path and a chain guide for the highest path, i. e. letting free the central path of the chain 266 Fig. 51 towing the air track. Every group of these matched simple chain guides provides caps 267A which, integral with the ends of each simple chain guide as well as equipped with through-hole, each engage with this hole either of the two adjustable ends pins 268 placed in a fixed part as support columns of the group. The caps 267A of the upper chain guide, centred (with clearance) from their centre hole and made not to translate as stationary stops (washer and Seeger) of such adjustable end columns 2G8,

oblige the position of the drive chain 266 and the caps 267A of the lower chain guide are thus only centred (with clearance) by the columns 268 themselves as a lower chain guide that does not interfere with the drive chain 266 that only rests on it.

The towing pulley 260 Fig. 50 that drives this triple chain 266 of the air track is equipped with two crowns assembled for engaging the rolls of the opposite tracks of the sprocket chain (the path of the central rolls is thus free) but rather than moved by a transmission this pulley 260 is driving as in direct drive to the ratio-motor 255 towing this air track. This triple chain 266 towing the air track moreover has auxiliary idle ratchets for a suitable surrounding angle to the towing pulley. Along this section of the air track, deviating the chain by the pipe of the air track, the lever 269 Fig. 51 with spike 272 that engages the air trolley 61+65 to the drive chain, cannot remain engaged and this lever is thus disengaged by a linear profile placed in a fixed part and assisted by a sensor for signalling the hindrance of an air trolley against the profile. The incoming air trolley, disengaged and in speed, by inertia overcomes this anomalous section of the air track.

For the correct tensioning of the towing triple chain 266 Fig. 55 (which, even if ironed by trade, is subject to lengthen as time passes) it is necessary to compensate quite larger differences compared to the case of the towing belt and therefore it is necessary to equip each air track no more with connecting pulleys on an elastic part but with straighteners with a spring (Fig. 45). The solution with straighteners with a spring results obviously valid even if the air track is equipped with a towing cog belt. The towing belt (belt or chain) of the air track results therefore in this case correctly stretched by means of at least one straightener with a spring, preferably placed in the kitchen also because there the air trolley is visible because the air track has no carter.

The straightener does not hinder the movement of the transiting air trolley as the profile R+S Fig. 46, placed in a fixed part for the release from the towing belt of the air track of the incoming air trolley, first opens (R section) and then holds open (S section) the grip scissor or

the direct drive lever with spike of this air trolley. The air trolley, kept disengaged in this way, by inertia overcomes the loop of the straightener as well as the fixed linear profile R+S that opens and maintains opened its grip system which, endowed with close-down with a spring, after having passed beyond the profile R+S, thus at once clamps again the towing belt of the air track. Thanks to this inertia'flight', the air trolley avoids all the problems due to the loop of the straightener of the air track.

The installation that is the object of this invention results also suitable against traffic problems (collision danger between an air trolley in stop and another approaching) and against power cuts, events that cause the immediate stop of the towing belt (a cog belt 96 Fig. 33 with double toothing or a triple sprocket chain 266 Fig. 55) and therefore the random stop of air trolleys.

At the restart (accelerating ramp to the ratio-motor 97 Fig. 39 or 255 Fig. 50'towing'the air track) an air trolley behind would face the profile R+S Fig. 46 of release placed at each straightener of the air track with a kinetic energy not sufficient to clear the obstacle of this fixed profile for opening the scissor plier or to rotate the spike lever with which the incoming air trolley engages to the towing belt of the air track. Even with a track running normally, such an air trolley would thus result'in a trap' (hindrance) between the towing belt that pushes it forward and the release profile R+S that hinders it. A temporized sensor placed in a fixed part guards the release profile and when detecting an'entrapped'air trolley it stops the air track and signals the problem.

After having restarted the towing belt of the air track a kitchen worker, using a suitable foot-board or the like, helps the'entrapped'air trolley to overcome the hindrance by pushing it with a raised arm and with a ridiculous force beyond the fixed release profile R+S Fig. 46. As an alternative if (kitchen) behind the'entrapped'air trolley an engaged air trolley threatens, mind that to each straightener of the air track the incoming air trolley does not result in grip with fixed electric sliding contacts and therefore cannot activate its photoelectric collision

warning switch at the restart of the air track (accelerating ramp to the'towing'ratio-motor) the engaged air trolley that arrives pushes the'entrapped'air trolley until normal speed and the hindrance for that straightener of the air track is resolved.

At the uncoupling and coupling stations (kitchen) the hindrance to the linear cam for the stop release is overcome by the intervention of the operator who, using a suitable foot-board or the like, helps the'entrapped'air trolley (visible as in the kitchen there is no carter of the air track) to overcome the hindrance by pushing it with a raised arm and with ridiculous force along this linear release cam to obtain the automatic insertion of the pin for stopping this air trolley.

As power cuts or traffic problems cause the stop of the air track, each descent in the public eating place is protected in access by a stopping restriction area (guarded by interlocked sensor) in order to prevent at the restart (accelerating ramp to the ratio-motor of the air track) that an air trolley to be lowered gets entrapped because not equipped with sufficient kinetic energy to clear the obstacle of this linear cam for the stop release of the incoming air trolley in the section that precedes the insertion of the stop pin.

In case of an air trolley leaving the stopping restriction area, the air trolley does not have to be intercepted but must proceed beyond, thus skipping that destined descent, and the interlocked sensor that guards that stopping restriction area thus precludes the descent sequence: this air trolley thus remains engaged to the towing belt of the air track and does not carry out the destined descent, which thus remains to be served.

The effective stroke, one-way, of each air trolley begins (Fig. 2) at the kitchen, stop for serving the respective guests at the tables (descent) and ends in a closed circuit returning to the kitchen. This usually does not require the towing belt (a cog belt 96 Fig. 33 with double toothing or a triple sprocket chain 266 Fig. 55) of that air track to be stopped, and thus any other trolley engaged to this flexible belt continues to advance towards its next destination.

Every air trolley in stop at a descent is disengaged from the towing belt as well as anchored in a fixed place and in grip with the electric contacts (sliding) placed in a fixed part of the descent and thus uses a photoelectric switch on board activated in order to deactivate the ratio-motor 97 Fig. 39 or 255 Fig. 50 of the air track to avoid the collision with any other overhanging trolley.

An equipment 91 Figs. 25; 27 or Figs. 59 ; 61 consists (in one piece only) substantially of three (or possibly more) food-carrier levels 91A Figs. 25 ; 59 each equipped with four rooms VA Figs. 27; 61 to be washed, sterilized and stocked up at each service run.

Every equipment can therefore serve several tables, also adjacent, for up to twelve (or possibly more) guests for each run. Each room of an equipment can house food, bottles (water, wine, or the like, two three-quarter litre bottles for each guest), crockery, cutlery, glassware, or the like, and their contents as well as the accessories connected to food and the respective invoice list FA Figs. 25; 59 which, as it identifies the respective room, is to be put correctly in view to the guest within the special seat, fixed in a removable way on the equipment on the edge of the relative food-carrier plane near the room. In order to allow the guests to withdraw their food, each invoice list FA, that details the order with the respective costs, has a title that indicates the air track VC, the table TL, the place at the table PO, the date and the time of emission as well as the data of the guest if available.

The guests of a descent, each remaining at his place at the table, can thus rotate either the whole equipment 91 Fig. 36 or Fig. 71 (supported by the revolving terminal 71 of the air trolley), unlocking the elastic spheric anti-rotation positioners (pressers) 41 (see Figs. 38; 73) placed on the terminal and therefore each have access to designated compartment, indicated by the respective invoice list FA Fig. 25 or Fig. 59 visible in the special fixed seat (removable) near the compartment.

The orders are selected by the guests by means of small mobile terminals 13 Fig. 4, assisted by menu on paper, available at the tables every four places or (very economic

alternative) by means of leaflets showing the menu of the day and on which each guest can mark the selected food.

While the food is brought within hand's reach of the guests with the system with combined screws as main part of the essence of the invention, the used crockery and cutlery is collected when the guest leaves his place at the table by the timely manual intervention of an operator, not a waiter as the installation does not require them, equipped with a special equipped trolley (5 ; SA ; 5B ; 5C ; 5D Fig. 4) ; every guest in fact at table uses an area under the table top where you can put the used crockery and cutlery (91F ; 91G Figs. 32; 31 and Figs. 54; 53). The above is the only manual operation requested to a room assistant besides uncorking (if necessary) wine bottles or the like and inspecting the public eating place as well as, if one wants to considerably reduce the cost of the total installation, against the payment collect the compiled forms of the orders and bring them to the kitchen.

Brief description of drawings Figs. 1 ; 2 show a schematic plan view and elevation view of a possible installation with two air tracks; Figs. 3; 4 are enlarged partial views from Figs. 1 ; 2.

Figs. 5 ; 6 show in elevation view a view of the trolley group and of the system with combined screws with an equipment on board as well as the lifting tool group; Figs. 17-20 and Figs. 22; 23 are enlarged partial views from Figs. 7-. 13.

Fig. 17 shows in plan view as Sect. A-A from Fig. 6 the terminal of the system with combined screws of the air trolley; Fig. 18 shows in elevation view the terminal ; Fig. 19 shows in plan view as Sect. B-B from Fig. 5 the three plates 31 that move the system with combined screws; Fig. 20 shows the fixing of these plates; Figs. 22; 23 show schematically in plan view as Sect. C from Fig. 5 the mechanical stop with teeth (made elastic) for the system with combined screws of the air trolley.

Figs. 25 ; 27 show a ready food-carrier equipment; Fig. 26 shows two serving plates each protected by a cap CO and stacked.

Fig. 28 shows the system for the stop and the start of an air trolley.

Figs. 34; 35 show an air joint between two main beams, connecting beams, two of the various columns (aligned) and an end keying of the structure, all indicative; Fig. 33 shows the plan of the air trolley on a track; Figs. 30; 31; 32 highlight the primary function of the invention.

Fig. 45 shows two straighteners with a spring for the towing belt of the air track; Fig. 46 shows a profile R+S placed in a fixed part near each straightener with a spring in order to disengage the gripping element of the transiting air trolley from the towing belt of the air track.

Fig. 47 shows a new arrangement for the air trolley and for its system with combined screws, in fact not equipped with a protection (the thus necessary anti-rotation columns are not represented); Fig. 47 moreover shows the motorization (with direct gear) for the drive chain of the air track; Fig. 48 shows a small pole (see also Fig. 55) placed in a fixed part for the stop of an air trolley; Fig. 49, Fig. 50 and Fig. 51 are enlargements of Fig. 47.

Fig. 49 shows the arrangement of a small pole placed in a fixed part (on air track) for the stop of an air trolley to be intercepted.

Fig. 50 shows, together with Fig. 47, the towing ratio motor for the triple chain of the air track placed in a fixed part as well as in direct drive to the triple chain.

Fig. 51 shows, together with Fig. 47, a new arrangement for the air trolley and for its system with combined screws, in fact not equipped with protection (the thus necessary anti- rotation extraction columns are not represented).

Fig. 55 shows (in plan view) the two extraction columns CS of an air trolley designated to the anti-rotation of the external pipe 35 Fig. 53 of the system with combined screws in absence of the protection 113; 114; 118 Fig. 36 of this screw system.

Fig. 58 shows a solution for tracks with electromechanical detection thresholds with sensors, for interfacing the destination cursors of the incoming air trolley, instead of

electronic reading thresholds (Fig. 51), for interfacing the plate of destinations of the incoming air trolley.

Figs. 59 ; 61; 62 show a food-carrier equipment with compartments, each equipped with a hatch housing with spring return and therefore self-closing rather than (Figs. 25 ; 27) using perimeter bands with manual closing and therefore not automatic.

Figs. 63 ; 64 show the safety lock aboard each equipment.

Fig. 65 shows the transmission with ratio-motor (and the respective stop sensors) for operating the group of the movable spokes of the tool instead of the steering-wheel 81A Fig. 36 to be operated by hand.

Fig. 66-70 show the passing of an equipment between the floating structure (with tracks) of the tool and the rails of the kitchen.

Fig. 71 shows the floating structure of a lifting tool equipped with traces (tracks) instead of rails.

In the drawings, for the public eating place: Figs. 1 ; 2 show the elevation view and the schematic plan of a possible public eating place arranged for housing two (different) air tracks 101; lOlA (Fig. 2).

Figs. 3; 31 highlight the level above floor of the air tracks as well as the level of the main air structure lOC+lOC'Fig. 34 and indicate the heights with'H'and'h', which may also be the minimum values allowed by current regulations, for public eating places.

With 10C ; 10C'Fig. 34 main beams are indicated, with a long span as they are joined with aerial joints to form a valid closed air structure, supported indirectly (only for important spans) also by columns 99 which, opportunely placed in a line and if necessary equipped with a connection able not to hinder the thermal expansions, allow free movement in the public eating place and in the kitchen. This in order to realize rooms of practical and welcoming appearance, not encumbered by columns and other connections to earth for an effective free

movement as well as fast transformable for example into dance-halls, halls for meetings, or the like.

The main beams 10C ; 10C'Fig. 34 are engaged directly to the external ends (keying or support in order to not to hinder the thermal expansions) from pillars 10M Fig. 35 adjacent to the walls of the public eating place and indirectly (only for important spans) also from columns 99 Figs. 3; 4; 34; 35 adjacent to junctions 10D Figs. 34; 35 between contiguous main beams These columns 99 Figs. 3; 4 and 34; 35, opportunely placed in a line and which do not hinder the effective free movement, are intended to support indirectly by means of small connecting beams 30 Figs. 34; 39 the respective joining of contiguous main beams 10C ; 10C' Fig. 34 of the main air structure, that bears (Fig. 39) the air tracks 101 (101A) Figs. 3; 4 and the related decorative carter 17 Fig. 3 View A. The circular carter 15B Figs. 34; 35, of limited height, decoratively mask the related column 99 with decorative artificial flowers, or the like, and simplifies free movement of the guests and of the staff by containing the base, which otherwise would jut harmfully, of the column 99.

With 10C ; lOC'Fig. 34 the main beams of the main air structure are indicated, that bears the air tracks 101 (lOlA) Figs. 3; 4 destined for the run in closed circuit of the air trolleys (or of the air trolley). In Fig. 39 a generic rectilinear air track 101 is indicated, made a fixed part because it is fixed, by means of the columns 102, at flanged pipes 98 integral with the main air structure. Fig. 58 shows, as a good alternative, a pipe 253A of the air track made directly integral with the air structure of the main beams 253. Each air track is destined to constrain every air trolley that runs on it in the two passive directions (transverse and vertical). Four circular sectors of the air track 11B Fig. 33 and four rectilinear stretches of the air track 11C form a closed circuit air track. With 101 (see also Fig. 39) the pipe constituting the air tracks is indicated. With 98 Fig. 39 a flanged support pipe for the air track 101 and the respective included elements are indicated.

With 16 Fig. 3 View to; Figs. 30; 31 a passage with automatic opening and closing for lowering and lifting one food-carrier equipment at a time is indicated. With 17 the decorative carter that hides the air tracks 101 Figs. 3; 4; 101A Fig. 4 limited to the air tracks themselves is indicated.

With 13 Fig. 4 a tiny mobile terminal is indicated.

With 7A; 7B; 7C; 7D Fig. 4 the uncoupling and coupling stations are indicated, prearranged respectively as better described in the following for the fast uncoupling (remove the return equipment from the trolley) and coupling (put an already ready equipment on the trolley). With 2E; 2B the washing basins are indicated. With 2A; 2C the sterilization basins are indicated. The equipment, once uncoupled from the air trolley, passes (manually pushed) from the rails of the tool (floating structure) to the rails of the kitchen and the operator separates the frontal seats (removable) for invoice lists and the housing (removable) of perimeter masking from the body of the equipment that, now open, is manually pushed (with the housing) to the washing basin and from there to the sterilization basin. With 1Z an equipment placed on one of the switches with the rail 1P used as a temporary deposit is indicated.

With 1H the two transit directions that the equipment can assume are indicated. The rotatory rail switches 1A, placed in the kitchen, allow an effective movement of the equipment. It is thus possible to sort, prepare and manage the equipment on the basis of the priority of delivery. The kitchen has a common line IL ; 1D ; IM ; IN (that follows the uncoupling, washing and sterilization stations of each track) for the preparation of the equipment. With 3A; 3B; 3C; 3D containers for cutlery, glasses, or similar are indicated. With 3F angle surfaces are indicated, with ready food, bottles, or the like. With 6 containers for separate collection are indicated.

With 8 Figs. 3; 4 passages for the entry and the exit of the air trolleys from the kitchen are indicated. The passages are equipped with panels with automatic opening and closing in order to insulate the kitchen from the public eating place.

In the drawings, for the trolley and for the food-carrier equipment: With 61+65 Fig. 39 the two plates in light alloy constituting the trolley together with columns 64 are indicated. With 103 twelve rollers (bearings) are indicated which together (Fig. 33) constrain the air trolley in all directions excluding the current one.

A wheelwork 60; 38A; 38 Fig. 33, placed aboard each air trolley and consisting of a driving gear, an intermediate gear and a final gear, transmits the motion from the ratio-motor 63 (also Fig. 39) on board of the air trolley to the three plates 31 Figs. 19 ; 20; 39 destined to drive the scroll 63A Fig. 39 in order to carry out the descents and rises of the system with combined screws 69; 68; 31; 66; 35 of this air trolley. As an alternative the wheelwork can consist of only one meshing, i. e. a driving gear and a final gear.

The cogs 38; 38A (Fig. 33) Figs. 22; 23 of such a wheelwork each use a disc (38' ; 38") equipped with a stopper tooth (40 ; 40A) in order to obtain mechanical stops for limiting the descents and rises of the air trolley. Appendixes 38B Figs. 41 ; 42; 22 integral with the final gear 38 and within the circumferential springs groups 38C housed in the disc 38'related to this final gear 38 make the stop elastic ; the impact is in fact essentially due only to the rotatory movements as (the equipment does not rotate but only translates) the translating movements, being slow, are almost uninfluent. In order to increase the stop stroke and thus reduce the forces of impact, also the other gear of the stop with teeth can be equipped with these appendixes, to be put within housed circumferential springs groups in the disc with stopper tooth related to this gear (not final) of the meshing.

The mechanical stop with teeth works both during service at the tables (public eating place) and at the uncoupling and coupling stations (kitchen). With 59 Fig. 39 a clutch is indicated situated after the ratio-motor 63 which contributes to protect (short-circuit torque

when the rotor is blocked) they ratio-motor, wheelwork and stop and acts as efficient dissipator to the backward movement that follows the stop impact.

With 34 Figs. 33; 39 the inductive proximity switch for deactivating the ratio-motor 63 is indicated. This proximity switch is calibrated to the frequency of the normal rotation speed of the square 37, made integral with the disc 38'Fig. 39 (Figs. 41 ; 42) of the stop relative to the final gear 38, and thus is to deactivate the ratio-motor 63 immediately after the intervention of the stop with teeth 38' ; 38"Figs. 22; 23. The proximity inductive switch thus protects the clutch 59 Fig. 39.

View V Fig. 33 (from Fig. 5) shows, in plan view, the above-mentioned wheelwork limited to the upper level of the air tracks and the columns 64 (see Fig. 39) that assemble the two main plates 65+61 of the air trolley, for housing a food-carrier equipment 91 Fig. 36 at the terminal 71 (revolving) of its system with combined screws.

Fig. 55 shows, in plan view, the above-mentioned wheelwork (limited to the level of the air tracks) for the case of only two gears and with system with combined screws of the air trolley without the protection, there are in fact the extraction columns CS in order to realize the anti-rotation of the external pipe of the system with combined screws.

With 91 Fig. 36 a food-carrier equipment is indicated. With 77 Fig. 37 (sect D) one of the eight hermetically sealed wheels is indicated that realize the sliding of the equipment 91 Fig. 36 on the rails 87A of the kitchen.

With 73'Fig. 37 the rails of the floating structure 73 Fig. 36 of the lifting tool are indicated.

As an alternative to these rails 73', the floating structure 73 Figs. 66; 68 can be equipped with tracks 73"Fig. 66 in order to facilitate both the setting-up and the operation of the lifting tool.

The rails 87A Figs. 67; 68 of the kitchen benefit of wide bevels (Figs. 68 ; 69; 70).

Fig. 27 shows the view plan of a ready surface of the food-carrier equipment with food, bottles, crockery and cutlery, glassware, or the like, and their contents. With 91B Fig. 31 three-quarter litre bottles are indicated (or the like), for example for water and wine. With

91C half a litre bottles are indicated (or the like), for example for beer. With 91D Fig. 32 seats for the bottles (or the like) are indicated. In Fig. 27 are indicated: with BI a cup, with PI a plate, with SU a support manoeuvrable by turns for easy access to the tray PN for the bread (or the like) and accessories, with IM a handle, with VI a three-quarter litre bottle for wine (or the like), one for each guest, with AQ a three-quarter litre bottle of water (or the like), one for each guest. With AP the maximum opening allowed by the two masking perimeter housings 91B Fig. 25 of a food-carrier plane is indicated. In Fig. 25 are indicated: with OL an oil, with VI (also Fig. 7) a three quarter litre bottle of wine, with AC a vinegar, with SA a salt, with PE a pepper. With FA Fig. 25 the invoice list is indicated (which shows the code of the place at the table PO, the code of the table TL, the code of the air track VC), with VA Fig. 27 a compartment of the food-carrier equipment is indicated. In Fig. 26 are indicated: with CO disposable removable snap-on caps, with PIC a dish with side dish, or the like, and with PI a dish with the main course.

Fig. 3 shows the extreme levels of the run of an equipment, the upper level 4S of the end of the rise and the lower level 4A useful for the tables. The upper level 4S (air), comprised within the track carter, allows not to hinder the customary free movement. After serving the first courses in very short time, the following can be fast sent to the guests also by order, launched from guest to the kitchen staff by means of the tiny mobile terminal 13 Fig. 4 available at each table every four places. If instead one wishes to reduce the cost of the installation remarkably abolishing the small terminals, the guest can only communicate with a waiter.

Every descent of the system with combined screws of the air trolley, although equipped with equipment, does not interfere with the space occupied by the guests, be they sitting or standing at their place at the table or crossing the public eating place, nor with the space occupied by kitchen staff.

In the drawings, for the original and innovative system of release and grip from the and to the belt towing the air track: If the belt towing the air track is a cog belt with double toothing, the air trolley is equipped, as a gripping element to the belt, with scissor (pliers), and if instead the belt towing the air track is a triple sprocket chain, the air trolley is equipped, as a gripping element to the chain, with a spike lever.

If the air track is equipped with towing cog belt 96 Fig. 39 with double toothing, each air trolley on such air track is thus endowed with grip scissor (pliers) 118; 105 Figs. 39; 29 locking with a spring for its automatic direct drive (clamping) and its automatic disengagement (release) to the and from the belt towing this air track, to avoid useless stops of any other air trolleys engaged to the belt towing that air track. The automatic engagements and releases of this grip scissor to the and from the belt towing the air track happen when the towing belt is moving.

With 106 Fig. 39 two gears for operating the two levers 118 are indicated; 105 as grip scissors (pliers) of the air trolley at the cog belt 96 towing the air track. As an alternative, the lever 118 Fig. 29 can be equipped with the toothed sector 106'and the lever 115 can be equipped with a toothed reel.

The oscillation (limited) of these pliers 118; 105 Fig. 39 in the plane orthogonal to the driving direction of the belt 96 can be positioned by means of a special cam, which does not prevent the scissor from swinging as it benefits from clearance in its seat. The closing stroke of the pliers (scissor) 118; 105 is limited by a special peg in order not to stop the towing belt.

The external lever 118 of the scissor is equipped with a ball joint for supporting the toothed presser 119 which swings in the plane of the belt 96, limited by a special pivot for correct entrance and grip to the toothing of the towing belt. The internal lever 105 (shorter) of the scissor is for the part of belt jutting out of the pulleys and has convex profile (not toothed) for a correct clamping.

When, for the start of the air trolley, the scissor 118; 105 Figs. 28; 29 engages the towing belt 96 Fig. 29 of the air track (for continuous motion except for traffic problems), the scissor acquires at once the whole normal speed of the towing belt 96 and therefore impacts (with the small pole P Figs. 28; 29 excluded) on the starting decelerator DA Fig. 28 on board the air trolley which thus benefits from controlled push for reaching normal speed itself and thus does not damage the towing belt 96 Fig. 29. The fulcrum shaft AF Figs. 28; 29 that carries the two levers 118; 105 of the scissor is consequently made slideable (spring return MR Fig. 28) as to the trolley body, because at the start (with the small pole P excluded) the scissor 118; 105 must at once engage the belt 96 Fig. 29 which is towing the air track for speeding up the body of the air trolley pushing on the starting decelerator DA Fig. 28, valid also for the backward movement, on board the air trolley.

If instead the air track is equipped with triple sprocket chain 266 Fig. 51, each air trolley 61+65 on this air track is equipped with a lever 269 with spike 272 as an element for its automatic direct drive (clamping) and its automatic disengagement (release) to the and from the drive chain 266 of the air track to avoid useless stops of any other air trolleys engaged to this chain towing that air track. Automatic engagements and releases of this lever with spike to the and from the drive chain of the air track take place when the drive chain is moving.

The spike 272 Fig. 51 hinged on the direct drive lever 269 benefits in the plane orthogonal to the driving direction of the chain 266 towing the air track from a limited oscillation as it is constrained between two opposite elastic ball pressers that as'zero'return restraints do not prevent this spike from swinging. In the plane of the drive chain 266 of the air track the spike is convex on its sides for a correct grip to the drive chain. The fulcrum shaft that carries the engaging lever 269 with spike is made slideable (spring return) as to the trolley body, as at the start the lever must at once engage the moving towing chain 266 and then speed up the body of the air trolley pushing on the starting decelerator, valid also for the backward movement, on board the trolley.

When the electronic reading threshold 274 Fig. 51 (bar codes), which checks the related descent, recognizes one of the table codes TL Fig. 25 or Fig. 59 of the plate TA of destinations of the incoming air trolley, or when the electromechanical detection threshold with sensors 111F ; 111F'Fig. 58, which checks the related descent detects cursors 111C; 111C'of destination of the incoming air trolley, the trolley must stop.

If the air track is equipped with cog belt with double toothing, the automatic disengagement of the air trolley from the towing belt is done by the external toothed lever 118 Fig. 29 which, being subject to meet the linear cam 110 placed in a fixed part and with automatic spring return when in operation, opens and is thus destined to open wide the internal toothed lever 105 (shorter in order to avoid the track pulleys) because the two levers (scissor) are connected among themselves from meshing and are therefore designated together with opening wide and to close (by means of the special spring 119A) respectively for the release and for the automatic direct drive from and to the towing belt 96 with double toothing of the air track.

If the air track is equipped with triple towing sprocket chain, the automatic disengagement of the incoming air trolley is still produced by such a linear cam 270 (110) Fig. 51 that, placed in a fixed part and with automatic spring return when in operation, serves to rotate, i. e. to exclude, the direct drive lever 269 with spike as a gripping element of the air trolley at the drive chain of the air track. This lever with spike of the air trolley also has a spring for its automatic re-engagement to the drive chain of the air track.

The electronic reading threshold or the electromechanical detection threshold with sensors that checks the related descent begins the descent sequence enabling the watching sensor on board the air trolley (supplied by sliding electric contacts placed in a fixed part) and the system with combined screws can so go down (external pipe) from its upper stop up to the level of watching (run A Fig. 29) in order not to exclude, with the clutch appendix 116 Fig. 29 of the air trolley, the linear release cam 110 or 270 Fig. 51, placed in a fixed part and with

spring return, for the gripping element of the air trolley. This electronic reading threshold 274 Fig. 51 or this electromechanical detection threshold with sensors 111F ; 111F'Fig. 58 moreover enables the sensor placed in a fixed part destined to perceive the arrival of the air trolley and to the signal the trolley-stopping electromagnet E Fig. 29 (or Fig. 49), placed in a fixed part and with two positions made stable, inserts (movement subordinated to the effective presence, when in operation, of the linear release cam for the gripping element of the air trolley) the small stop pole P Figs. 33 ; 55 that as fixed part so activated is destined to meet (when the scissor plier or lever-operated with spike are disengaged) the stop decelerator DR Fig. 28, assisted by an external spring MB for the recharge, placed aboard the incoming air trolley. At the backward movement of the air trolley the decelerator DA (valid for the backward movement as well as for the start) on board the trolley meets the small stop pole.

Every air trolley is thus endowed with two decelerators (DA ; DR) and with springs (MA ; MB) for their free recharge. The insertion of the small pole P Figs. 28; 29 stops the air trolley and enables the consent to the descent of the system with combined screws.

The descent of the system with combined screws is automatic in the public eating place because it begins at the complete opening of the passage of the air track 16 Fig. 3 View A but works on command in the kitchen. The rise, also on command, of the system with combined screws causes the automatic re-engagement of the gripping element (scissor plier or spike lever) of the air trolley to the towing belt (cog belt or sprocket chain) of the air track as described below. The rise signal (four pulses) enables the sensor 62 Fig. 39 destined to commute the electromagnet (in a fixed part) E Fig. 39 or Fig. 49 in order to be able to exclude the small trolley stop pole P Figs. 28; 29.

The following automatic re-engagement of the air trolley to the towing belt (cog belt or sprocket chain) of the air track occurs almost at the end of the lifting stroke of the system with combined screws and is due to the external pipe 117 Fig. 36 of the protection which, activating (at the end of its track), near its upper stop, the release shaft 100 Fig. 29 (with

limited stroke and with spring return as well as equipped with the trolley-clutch appendix 116) in order to keep the linear cam 110 of release excluded, thus automatically frees (movement subordinated to the return of the small stop pole P Figs. 28; 29) the gripping element (the scissor plier 118; 105 Fig. 29 or the lever 269 Fig. 51 with spike) of the air trolley whereat the gripping element, endowed with closing spring 119A Fig. 29, clamps again the belt towing the air track for making move the air trolley again. The air trolley has a controlled push, also for the start, and thus does not damage the towing belt.

If the electronic reading threshold (bar codes) that checks the descent does not recognize any of the table codes TL of the plate TA of destinations of the incoming air trolley it must not to stop but proceed beyond, and so the electronic reading threshold precludes both the watching (i. e. precludes the run A Fig. 29) of the system with combined screws, and the insertion of the small trolley-stop pole P and this air trolley, excluding with its direct drive appendix 116 raised up (screw system with upper stop) the linear release cam 110 or 270 Fig. 51 (and therefore remaining engaged with the towing belt), passes the station. If the incoming air trolley, at the restart of the air track (stopped by a power cut or by traffic problems), restarts from the stopping restriction area that protects the descent, in this case the electromagnet with automatic spring return for the release cam is activated in order to ensure in any case (independently of the result of the descent comparison) the exclusion of the release cam and the air trolley thus is not disengaged. Where on the other hand it is convenient to equip the installation with electromechanical detection thresholds rather than with electronic reading thresholds, in case of a negative result of the descent comparison between the threshold sensors (placed in a fixed part) and the destination cursors of the incoming air trolley, the electromechanical thresholds will assume these inhibitory functions.

If each linear cam for the automatic disengagement of the gripping element (scissor plier or spike lever) of the incoming air trolley is managed by an electromagnet with two stable positions, rather than as already described by an electromagnet with automatic spring return

(for the automatic recharge of the cam) and from an automatic release shaft (which if activated excludes the cam), this allows to eliminate the recharge spring, the group of the release shaft and the watching run that precedes the descent of the system with combined screws.

In the drawings, thanks to the original and innovative system with combined screws destined to the manoeuvres of lowering and lifting the equipment on board: The bushing 62A Fig. 39, made integral (or in one piece) with the final gear 38, is centred by two bearings as to a bushing welded to the plate 61 of the air trolley. The bushing 62A, equipped with two sliding cushions, on its part centres the fixed screw 68. With 44; 44A two pairs of axial retaining half rings are indicated, each restrained by the relative bushing in order to allow the axial assembly of the system with combined screws, fixed to the trolley.

The pipe 68 Fig. 39, entirely threaded on the outside excluded its upper end, acts as fixed screw and on its part centres the sliding inner guide pipe 69. This fixed screw 68 does not rotate and does not translate because it is axially constrained by the half rings described above 44; 44A as well as constrained not to rotate by the lever 42 subject to the fixed pivot 36.

The scroll 63A Fig. 39, threaded on the inside, acts on the fixed screw 68 described above (threaded on the outside) and is crossed by the three rigid plates 31 Figs. 39; 19; 20 (equidistant) indirectly driven by the ratio-motor 63 Figs. 39; 33. The scroll 63A, therefore, rotates and translates vertically. These three plates 31 Figs. 39; 19; 20 are made integral with the bushing 62A Fig. 39, made integral (or in one piece) with the gear 38, and therefore are driven by the final gear 38 Figs. 39; 41; 42; 33; 32 which meshes with the intermediate gear 38A Figs. 33; 23 which in turn meshes with the driving gear 60 Fig. 33 (for a wheelwork with only two gears see Fig. 55). The pipe 66 Fig. 39, entirely threaded on the outside, is made integral with the scroll 63A by means of a thread of internal connection blocked with a pin, or the like, and therefore rotates and translates vertically with the scroll.

The external pipe 35 Fig. 39, equipped with pipe connection 35A threaded inside, acts on the pipe 66 described above entirely screw threaded on the outside. The external pipe 35, though made not rotating as described later on, thus benefits from the linear stroke of the scroll 63A and adds to this the stroke derived from the rotation that the scroll carries out (the thread of the fixed screw 68 and that of the above-mentioned rotating and translating pipe 66 integral with the scroll are opposite).

The central pipe 69 Fig. 39, inside the fixed screw 68 which is obtained from a pipe supplied from trade lapped internally (pipe for cylinders), is equipped with two sliding cushions (guide bands) 69A in PTFE, or the like, and is furthermore assisted by the sliding cushion 69B Fig. 36 placed at the lower inner end of the fixed screw 68 Fig. 39 and thus acts as centring sliding element.

The screw threaded pipe 66 Fig. 39, translating by rotation because integral with the scroll 63A, benefits from the sliding central guide pipe 69 because it is made downwardly integral, by means of connecting screw thread (Figs. 36; 38), with the bushing (equipped with bearing 69E) 69D housed in the guide pipe 69 Fig. 39. The threaded pipe 66, destined to translate by rotation because it is integral with the scroll 63A, avails itself therefore as centring guide of the threads in grip with the scroll 63A on the fixed central screw 68 as well as of the sliding inner guide pipe 69 described above.

The external pipe 35 Fig. 39, destined only to translate because it is constrained not to rotate according to the following description, avails oneself instead which centring guide of the high number of threads in grip with its pipe connection 35A on the screw threaded pipe 66 as well as, by means of the sliding cushion 69C Figs. 36; 38 of the bushing 69D, of the sliding inner guide pipe 69 Fig. 39.

In Fig. 36 the numerical references 113; 114; 117 indicate the protection, with composed pipes, destined (apart from excluding the scissor-opening linear cam) to follow the descents and rises of the system with combined screws of the air trolley as well as to prevent the

rotation of the external pipe 35 Fig. 39 of this system with combined screws. The internal pipe 113 Fig. 36 of the protection is fixed at the bushing (of centring) welded to the upper plate 61 Fig. 39 of the air trolley. 114 Fig. 36 indicates the intermediate pipe of the protection, which pipe, by means of opposite tongues 114A Fig. 39 within traces, transmits the anti-rotation constraint between the internal pipe 113 Fig. 36, fixed to the trolley, and the external pipe 117, fixed by means of external connecting screw thread blocked with pin or the like on the bottom flange 113A (opposite to the terminal 71) of the system with combined screws which moreover blocks with connecting screw thread the external pipe 35 Fig. 39 (thus made non- rotating).

This protection 113; 114; 117 Fig. 36 for the system with combined screws can be omitted entrusting the re-engagement function of the air trolley to the towing belt and the anti-rotation function of the external pipe of the system with combined screws of the same trolley to other components. In fact by entrusting the management of the linear release cam, rather than to an electromagnet with spring return, to an electromagnet with two stable positions, the function of re-engagement with the towing belt does not need (Fig. 39) the external pipe of the protection which, by activating (at the end of its track), near its upper stop, a special mechanism, excluded the release cam 110 Fig. 29 or 270 Fig. 51. Moreover by entrusting the anti-rotation constraint for the external pipe of the system with combined screws, rather than to the extraction pipes 113; 114; 117 Fig. 36 that form the protection, to two extraction columns CS Fig. 55 fixed on the upper part on the body of the trolley and downwardly made integral (by means of collar) with the external pipe of the system with combined screws, also the anti-rotation function of this pipe is absolved and the protection can thus be omitted. Figs. 47; 71 show a system with combined screws without the protection 113; 114; 117 Fig. 36 (but the thus necessary anti-rotation extraction columns CS are not represented).

Each equipment is equipped with two opposite retaining spring pins 80 Fig. 36 or Fig. 71 and Figs. 17 ; 18 intended for uncoupling or coupling themselves from or to the terminal (revolving) 71 of the system with combined screws of an air trolley. With 50 Fig. 17 the conical surface of the terminal 71 is indicated, for overcoming down hill (coupling station) the two spring pins 80 of an equipment which in this way is admitted in any case directed, also for the coupling operation. With 43 Fig. 43 two sectors in long-wearing plastic material of the equipment are indicated, intended for receiving (centring) the terminal 71 as an end (revolving) of the system with combined screws of an air trolley.

The bottom flange 113A Fig. 36 (opposite to the revolving terminal 71) of the system with combined screws, not rotating as to the air trolley, is equipped with imprints on the lower side, as retentions for the anti-rotation elastic ball positioners (pressers) 41 (see Fig. 38) of the revolving terminal 71 that bears the equipment, referred to the correct phasing both for the places at the tables (public eating place) and for the uncoupling and coupling operations of an equipment (kitchen).

The terminal 71 Fig. 36 of the system with combined screws of the air trolley, as its revolving appendix, also destined to couple as well as uncouple an equipment, is equipped with such elastic ball anti-rotation pressers 41 Fig. 38 or Fig. 73 in order to find the imprints and thus stabilize the set angle. The equipment 91 Fig. 36 or Fig. 71 described above is therefore phaseable both by the staff of the uncoupling and coupling stations and by the guests by overcoming manually the anti-rotation elastic ball positioners (pressers) 41.

The terminal 71 Fig. 36 or Fig. 71 and Figs. 17 ; 18 is equipped with two blind traces 53; 54; (49A) Fig. 17 (opposite) as a sure coupling constraint for an equipment as well as with two passing traces 51; 52; (49B) (opposite) for uncoupling. Every blind track communicates to a limited degree with the related (adjacent) passing-through track. This coupling constraint is stable and sure. Each equipment is equipped with a lock 91C Fig. 63 (subject to key CH and equipped with a cam PA Figs. 63 ; 64) in order to ensure the safety of the equipment on

board against ill-willed people that, operating together, though with extreme difficulty, could otherwise manage to uncouple the equipment from the terminal and use it as blunt instrument.

As an alternative such a safety lock can be placed (rather than on the equipment) on the terminal of the system with combined screws of the air trolley.

By rotating manually the equipment at the uncoupling or coupling operations as described later on, the spring pins 80 Figs. 17 ; 18 and Fig. 36 or Fig. 71 of the equipment first meet the respective opposed useful traces (uncoupling or coupling) of the terminal and so, by overcoming the anti-rotation elastic ball pressers 41 (see Fig. 38 or Fig. 73), the assembly equipment+terminal reaches in the rotated state the imprint (retention) of interest that ensures the correct phasing for the releasing operation or for the coupling operation.

In the drawings, for the lifting tool destined to the manoeuvres of uncoupling and coupling for the detachment and the loading of an equipment from the and on the respective air trolley: Every lifting tool (Fig. 43 or Fig. 71), valid both for uncoupling and coupling a trolley, allows, when the equipment has beeen raised, both the appropriate rotation of phasing of the equipment until the respective imprint (retention) of interest for uncoupling (corresponding to the rails 73'Fig. 36 or to the tracks 73"Fig. 66 of this tool) as well as the appropriate rotation of phasing until the respective imprint (retention) of interest for coupling (corresponding to the not throughgoing traces 53; 54 Figs. 17 of the terminal). These two imprints (uncoupling and coupling) are placed at the ends of the angle a (alpha) Fig. 18. Every rotation described above until the imprint (retention) of interest for the uncoupling operation or until the imprint (retention) of interest for the coupling operation requires the rise C Fig. 37 or Fig. 72 (Sect. D) of the equipment which otherwise would be hindered by the rails or be the tracks (of the floating structure) of the tool. The stroke of the lifting tool is defined by two proximity sensors 221; 221A Fig. 65 such as electromechanical stops if the nut screw of action 218 is power-operated, or by a screw threaded ring 84 Fig. 43 as upper mechanical rabbet for the

anti-rotation pin 83 (that slides in a slot of the fixed base pipe 88A) if the steering-wheel 81A that drives the nut screw of action is not power-operated. Also only one tool can perform the uncoupling and coupling operations of the equipment for its track.

88 Fig. 43 indicates the sliding central shaft that carries the group of the lifting spokes, each equipped with a load-bearing sphere 79. The shaft, driven by the base pipe 88A and constrained not to rotate by the pin 83, is destined to scroll axially as it is integral with the screw 82 Fig. 43 or 218A Fig. 65 which realizes the lifting manoeuvre of the group of the lifting spokes 78 by means of the motorizable steering-wheel 81A Fig. 43 or the ratio-motor 215 Fig. 65 that drives the related nut screw of action (respectively 81 or 218) axially constrained by the weight of the elements above it. The group 78 Fig. 43 or Fig. 65 of the lifting spokes, vertically sliding, is destined to keep the equipment 91 raised on the load- bearing balls 79 Fig. 43 during its manual rotation on behalf of the operator until the imprint of interest (retention for uncoupling or for coupling) at the angle a (alpha), see Fig. 18. This screw 82 Fig. 43 or 218A Fig. 65 if it is with recirculation of balls has almost no reversibility.

The steering-wheel 81A Fig. 43 in any case has modest control force. The group 78 Fig. 65 of the lifting spokes of the tool is motorizable by a simple transmission 216; 216A; 217 with toothed belt driven by the ratio-motor 215 with incorporated torque limiter. The driven pulley 217 of this transmission is in fact integral with the nut screw of action 218 which, constrained not translate by the weight of the overhanging elements, engages the screw 218A made integral with the central shaft of the tool in order to realize the runs of the group of the lifting spokes.

The upper structure (floating) 73 Fig. 43 or Fig. 71 of the tool rests with its load-bearing balls 74 on the three stationary equidistant spokes 75 of the tool, made as a fixed part as they are centred by the sliding central shaft 88 Fig. 43 as well as engaged axially by the weight of the overhanging elements and prevented to rotate by means of the two shafts 76 Fig. 43 or 219 Fig. 65 (that engage one of the three stationary spokes 75) made indirectly integral with the

central shaft 88 Fig. 43 (vertically sliding) constrained on its part by the proper anti-rotation pin 83 not to rotate. The upper structure 73 Fig. 36 or Fig. 71 of the tool is made floating as it is equipped with the load-bearing balls 74 that rest against the fixed part below with spokes 75 of the same tool and moreover results self-centered again by opportune springs 75A in order to draw with its retention pivot 71A from the seat with wide opening of the terminal 71 of the system with combined screws (descended) of the first air trolley in stop for centering the floating structure to the seat. The retention pivot 71A, guided sliding within the floating structure 73, is held drawn back by the springs 71B Fig. 43 placed in a fixed part and pushed forward by the central sliding shaft 88 of the lifting tool in order to draw from the conical seat of the terminal 71 descended for centering the floating structure 73 to the seat. The pivot 71A, that must self-centre to the terminal 71 (descended) of the air trolley in stop, is not rigidly constrained to the sliding shaft 88, that in fact grants him radial liberty, and therefore it automatically centres the floating structure 73 of the tool to the terminal 71.

When the equipment has been raised in this way the operator can (uncoupling station or coupling) perform the manual rotation of the equipment until the respective imprint (retention) of interest, in order to carry out the uncoupling or coupling of the grip pins 80 Figs. 17 ; 18 and Fig. 36 or Fig. 71 of this equipment 91 from or to the terminal 71 of the system with combined screws (descended) of the first air trolley in stop. During the rotation described above up to the rabbet (retention) of interest the equipment is thus centred both as to the system with combined screws, by means of the terminal (revolving) 71 of this system with combined screws, and as to the floating structure 73 of the tool, by means of the retention pivot 71A of the floating structure which engages the seat with wide invitation of the terminal 71 (descended) of the system with combined screws. The equipment 91 Fig. 5, now rotated to the rabbet (retention) of interest placed on the bottom flange 113A Fig. 36 or Fig. 71 (opposite to the revolving terminal 71 and not rotating), is then lowered, held phased by the traces of interest of the same terminal, by means of the motorizable steering-wheel

81A Fig. 43 or the ratio-motor 215 Fig. 65 activated for lowering the group of the lifting spokes, subject in fact to vertical translation only. 49A Fig. 17 indicates the path that the food- carrier equipment carries out in rising after the coupling to the terminal of the system with combined screws of the air trolley. 49B indicates the path that the system with combined screws carries out in rising after the release of the two diametrically opposed spring pins 80 of the equipment.

The air trolley returned to the uncoupling station automatically in stops at the lifting tool and the operator, by a special push-button, commands the descent of the system with combined screws of this air trolley that was in stop, after which he performs (as indicated above) the uncoupling. A proximity sensor 89 Fig. 36 or Fig. 71, placed in a fixed part near the releasing tool, detecting the presence of the protrusive pellet 90 of the equipment, checks the correct phasing of the equipment to the corresponding rabbet (retention) of interest of the angle a (alpha) Fig. 18. This control is necessary at the uncoupling station for ensuring the uncoupling of the equipment and in order to enable the push-button, interlocked with the phase sensor for uncoupling, that controls the rise of the system with combined screws of the air trolley. During the descent of the lifter group 78 Fig. 43, thus moving back the related load-bearing balls 79, the equipment finds again first, C quote Fig. 44 sect. D after the uncoupling, with its eight sliding wheels 77, the inferior rails 73'Fig. 36 or the tracks 73" Fig. 66 of the floating structure of the tool while, sinking on, at the stopper the autocentering pivot 71A Fig. 43 of the floating structure 73 results withdrawn (automatically called back by the related springs 71B) and the equipment, after the operator has commanded the rise of the system with combined screws of the air trolley, it thus can be pushed manually towards the rails of the station rotatory exchange or directly to those of the kitchen.

The system with combined screws, once ascended to the level of the air tracks, causes the automatic re-engagement of the air trolley in stop to the track towing belt and the air trolley thus moves, within the kitchen, from the uncoupling station to the coupling one

waiting to receive on board a food-carrier equipment. The operator at the coupling station pushes a ready equipment on the floating structure 73 Fig. 36 or Fig. 71 (equipped with rails 73'Fig. 36 or tracks 73"Fig. 66) of the tool and, by a special push-button, commands the descent of the system with combined screws of the first air trolley in stop after which he works (as already described) for coupling it.

A proximity sensor, placed in a fixed part near the coupling tool, detecting the presence of another protrusive pellet (but with a different radius) of the equipment, checks the correct phasing of the same equipment as to the corresponding rabbet (retention) of interest of the angle a (alpha) Fig. 18. Every equipment is therefore equipped with two pellets (phase for uncoupling, phase for coupling) but positioned with a different radius. This control is necessary at the coupling station for ensuring the coupling of the equipment and in order to enable the push-button that controls the rise of the system with combined screws of the air trolley. The operator at the coupling station, by means of the special push-button, interlocked with the phase sensor for coupling, commands the rise of the system with combined screws of the air trolley in order to couple and send the equipment to service at the tables.

It is understood that the drawings only show an example given only as a not limitative practical demonstration of the invention, as this invention may vary by arrangements, forms, sizes, or the like, without leaving the domain of the concept that the invention discloses.