Machine for handling floor-covering elements.

The present invention concerns a machine for handling floor-covering elements during their deposition on and removal from the floor.

Technical field:

In premises which are used for periodically occurring events, such as fairs, exhibitions, conferences or festive events, floor-covering elements are often used. These elements are deposited prior to each event and they are removed after it for cleaning and subsequent re-use. Elements of this kind usually are in the form of carpets having a top face of a textile material and a reverse face of rubber or synthetic resin in contact with the hard sub-floor of the premises. The carpets may have a size of e.g. 1 x 2 meters. Alternatively, other slab-like elements may be used in-the same way.

Background:

Deposition and removal of such floor-covering elements were effected manually until the advent of the invention. The standard mode of operation was for two men to jointly lift the floor-covering elements, one by one, from a stack of elements and lay them down in rows on the surface to be covered. The removal was effected in a corresponding manner, the removed elements being stacked in piles and carried away for cleaning or other treatment. On the whole, the only aid used was a carriage on which the elements were transported. In some cases, fork-lift trucks or similar lifting implements were used to handle the piles of elements to transfer them from a storage to the premises where they were to be used and also for transport in the opposite direction, but despite aids of this kind the physical labour to effect the actual deposition and removal of the elements remains.

Technical problem:

Premises of the kind outlined in the aforegoing are of en very large and the elements must have a certain minimum size, e.g. the one indicated above, in order to remain immobile, which makes them very heavy. For these reasons, considerable, and in addition heavy work is involved in covering the floor of such premises with the elements and in removing them afterwards. Consequently, there is a need for automatic means to perform the work involved.

The solution:

The invention provides a irachine for handling floor-covering elements. It comprises a carriage which is arranged to be displaced across a base to be covered by the elements, at least one magazine on the carriage to acccmrodate at least one pile of floor-covering elements, a feed-out device on the magazine for discharge of the elements therefrom, a conveyor arranged adjacent the feed-out device for displacement of the elements sequentially one by one from the magazine to a point close to the base, whereby upon operation of the machine the elements will be discharged from the magazine and advanced onto the conveyor and be deposited by the latter onto the base in a row while the carriage is moving along the surface of the base on which the elements are to be deposited, said conveyor being adjusted to the speed of travel of the carriage to ensure that the conveyor means thereof run at a somewhat higher speed while being allowed to slide against the elements, whereby the progressively discharged elements will be pressed against the edge of the immediately previous element.

Advantages:

The invention provides a machine for handling carpets and other floor-covering elements which are intended for temporary use. Owing to this machine, the work involved in depositing and removal of these elements may be performed in an automated manner while relieving the person performing the work of the heavy physical labour involved.

Brief description of the drawings:

The accompanying drawings illustrate one embodiment of the machine in accordance with the invention. Fig. 1 illustrates the machine in a view from above. Fig. 2 illustrates the machine in a lateral view and Fig. 3 illustrates, likewise in a lateral view, a detail component of the machine on an enlarged scale compared with Figs. 1 and 2.

Best mode of carrying out the invention:

The machine illustrated in Figs. 1 and 2 comprises a stand 1 in the form of a carriage frame 2 having two pivotally mounted front steering wheels 3 and a rear wheel 5 which is arranged to be rotated by a driving motor 4. As appears from the drawings, the front wheels 3 may be turned by means of a control rod 6 and it is assumed that the driving motor is connected to actuating means which preferably are positioned at the end of the control rod, to operate the driving motor.

The frame 2 supports a magazine 8 having enclosing walls 9 forming a shaft 10. The shaft is adapted to accx-smmodate therein a large number of stacked floor-covering elements 11 carried by a table 12. The table 12 is supported by a lifting mechanism 13. Fig. 2 shows the covering elements 11 placed in the magazine so as to rest on a load pallet 14 which thus is carried by the lifting table 12.

The upper end of the magazine 8 is arranged to be covered by a feed-out conveyor 16 comprising a frame 17 supporting on its lower face a conveyor 18 the lower part of which could be regarded as a lid covering the shaft 10. The conveyor 18 is arranged to be driven solely with its said lower part travelling towards the right as seen in Fig. 2. The conveyor 18 is equipped with a projecting rail 50. In the right-hand wall of the shaft intermediate the lower part of the conveyor and the upper edge of the wall there is a slit through which the elements 11 may be discharged. From' the lower position illustrated in Fig. 2 the feed-out conveyor 16 is arranged to be pivoted upwards on the upper end of the shaft 10 by means of positioning means 19.

At said discharge side of the magazine 8 (towards the right as seen in Fig. 2) two conveyors are mounted, viz. one intermediate conveyor 22 and one end conveyor 23. The intermediate conveyor has one upper shaft 24 and one lower

shaft 25. The two shafts support a number of pulleys 26 thereon and drive belts 27 running between the pulleys serve as a conveyor belt. The shafts are supported by two rods 28 fitted with means to tension the belts 27. The rods 28 pivotally support the entire intermediate conveyor by means of pivot shafts which are attached to u rights 30 forming part of the stand 1 and also supporting the feed-out conveyor 16. The intermediate conveyor may be pivoted about the pivot shafts to be lowered from the operative position illustrated in Fig. 3 to a conveying position with the aid of positioning means 32 which support the outer end of the intermediate conveyor.

Outer uprights 34 of the stand 1 support the end conveyor 23. Also the latter has two shafts 35 and 36 with pulleys 37 thereon and drive belts 38 running between the pulleys. The shafts are supported by rods 39 and the entire device is pivotable about attachment points in the uprights 34. In the operative position illustrated in Fig. 3 the outer end of the end conveyor 23 is supported by caster wheels 42 resting against the base 43 on which the wheels 3 and 5 are intended to run. In the position of transport, the end conveyor may be pivoted to an upper position on top of the intermediate conveyor 22 when the latter has been lowered by the positioning means 32.

As illustrated in Figs. 1 and 2 guiding rules 51 are attached to the ends of the outer rod 39. In the downwards-folded position of the end conveyor 23 shown in the drawings, they rest by means of one edge against the base or are positioned immediately above the latter.

The upper belt parts of the intermediate conveyor 22 and the end conveyor 23 extend on an essentially straight line commencing underneath the edge of the feed-out conveyor 18 and ending close to the base 43, i.e. the floor on which the elements are to be deposited. The two conveyors are arranged to be driven by means of motors, not shown, and their directions of movement are identical but reversible, however, they always move in such a direction that together they may be used for feeding either upwards or downwards.

The lower end of the end conveyor 23 is shown on an enlarged scale in Fig. 3. In addition to the components already described, this drawing figure also shows that the rod 39 supports a number of shafts 46 via arms 45. On these

shafts are pivotally mounted a corresponding number of arms 47 having outer fork-shaped ends including shafts 48 which support diamond-shaped blocks 49. One of the long sides of the blocks is arranged to rest on the base 43. The arms may be pivoted individually to the position illustrated in dash-and-dot lines in which they assume a position sandwiched between the associated belts 38 and do not interfere with the work of the motor. The arms 47 with the blocks 49 thereon are automotive and lack guiding as well as driving means.

Initially, the deposition of the floor elements will be described:

In the starting position, the machine is loaded with a pile of the ^' elements 11 inside the magazine. For rational handling, the pile preferably is displaced while resting on a load pallet with the aid of a fork lift truck, the magazine being arranged to allow insertion therein of the pallet.

The elements should be deposited along straight lines so as to cover the floor or ailes along the floor. Preferably, the lines are marked by means of painted lines. During the deposition the machine may be moved along one of the lines of this kind while being guided by the front wheels 3 with the aid of the control rod 6 while at the same time the driving motor 4 is operated to propel the machine (towards the left as seen in Fig. 2) by means of the wheel 5. During this movement all three conveyors, viz. the feed-out conveyor 16, the intermediate conveyor 22 and the end conveyor 23 are kept in motion, with the lower part of the feed-out con¬ veyor 16 travelling towards the right as seen in Fig. 3 and the upper parts of the other two conveyors travelling in the same direction. The lifting mechanism 13 is actuated to lift the lifting table 12 and the pallet 14 with the pile of elements 11 stacked thereon in such a manner that the upwardly facing top face of the uppermost carpet will be brought into contact with the moving conveyor 18. Upon abutment of the driving rail 50 of this conveyor against the left edge of the element below, the conveyor will entrain the element and discharge it through the slot, whereby the element will be thrown onto the belts of the intermediate conveyor 22. As the elements are gradually removed from the pile, the lifting table is raised higher and higher, ensuring that new elements are constantly discharged onto the intermediate conveyor 22.

From the intermediate conveyor 22 the elements are advanced onto the end conveyor 23. During the discharge operation, the arms 47 should assume their downwards folded position illustrated in Fig. 2 and thereby they will act as sliding ramps, instrumental in depositing the elements onto the sub-floor. By being conveyed on the belts 38 of the conveyor 23 and the arms 47 the elements are advanced downwards, onto the sub-floor 43, and form a row of elements behind the machine as the latter progresses along the sub-floor.

The guiding rules 51 guide the end conveyor 23 along the elements already deposited and gradually they will center the elements just deposited in alignment with the row of elements already deposited. Steering of the carriage on which the machine is mounted is performed with the aid of the control rod 6 to ensure that the carriage moves in the direction of extension of this row of deposited elements. This operation is facilitated if the sub-floor is provided with the painted lines mentioned in the aforegoing.

However, misalignment may occur as regards the position of the carriage relatively to the row of elements. To compensate for such deviations, the end conveyor 23 is slightly pivotable in the lateral direction. Preferably, this is achieved by articulating the bars 39 of the conveyor on vertical shafts at either end. The extreme end of the end conveyor adjacent the rules 51 consequently may move laterally, whereby the entire conveyor will perform a parallelogram movement during which its shafts 35 and 36 remain arallel throughout.

The discharge of the elements onto the sub-floor may be effected in such a manner that the trailing end of each new element as seen in the direction of travel will be pressed against the front edge of the element deposited irrmediately before, so that a continuous surface is formed. This is the situation after deposition of the first element or a couple of the first elements which is supervised manually. In the course of the continued deposition, the machine is to be driven forwards and need only be controlled for movement along the line of deposition. This requires some cooperative control of the varous components of the machine.

In order to achieve the continuous row of elements indicated above the speed of advancement of the-belts 38 of the end conveyor must be slightly

higher than the speed of advancement of the machine. Owing to this arrange¬ ment, the belts will tend to advance the elements at a higher speed than the speed at which the sub-floor may receive the elements as a result of the speed of advancement of the machine, and consequently the previously mentioned edge-to-edge ^* engagement will occur while at the same time the bottom faces of the elements slide against the belts. The feed-out conveyor 16 and the - intermediate conveyor 22 then serve to constantly advance elements in such a manner that elements are always available to ensure that the end conveyor 23 may discharge them in the order indicated, with adjacent elements being pressed against each other edge to edge. In order to ensure that this happens without, however, any risk of over-feeding, which would lead to the elements piling up on the end conveyor, the first two conveyors preferably are provided with control means which are arranged to sense the amount of elements available on the end conveyor 23. It is known to use photoelectric sensors for this type of control means. Such sensors are arranged to detect that elements, spaced a limited distance apart, actually are advanced at the upper end of the end conveyor to allow said conveyor enough time to cover said space and ensure that the elements abut edge to edge when discharged frcm the lower end of the conveyor. The maintenance of this condition may be effected through continuous speed control of the two upper conveyors or by operating them intermittently. Also the movement of advancement of the lifting table 12 upwards should be controlled accordingly.

The device may operate in the manner described above until the magazine is empty.

To remove the elements, the machine is operated in the reverse direction, i.e. starting with the end conveyor 23 with the arms 47 thereon pivoted to the position illustrated in Fig. 3. Obviously, there should be enough space in the magazine 8 for reception of the removed elements and the lifting table 12 should be lowered so that a vacant space is formed at the upper end of the magazine. The positioning means 19 are actuated to lift the feed-out conveyor 16, whereby the upper mouth of the magazine will be opened. The intermediate conveyor 22 and the end conveyor 23 are set in motion with their drive belts 27 and 38, respectively, operating in the upwards direction, towards the magazine 8. They are driven at a speed which is higher than the speed of travel across the sub-floor.

During driving, the rules 51 are used for guidance along the row of elements deposited. When in the course of movement of the machine the foremost blocks 49 contact an edge of an element they will, on account of their pointed con¬ figuration, project in underneath the elements, the latter being supported at its opposite edge by the rest of the elements in the row. In the course of the continued advancement of the machine the element will slide upwards onto the arms 47 until it reaches the belts 38 which advance the elements frictionallv and via the intermediate conveyor 22 throw them in over the magazine 8. When the element reaches the upper mouth of the magazine it falls down into the latter while being slowed down somewhat by the air cushion underneath. A fixed stop means, not shown, stops the element when the latter reaches a position directly above the magazine.

Preferably, the speed of the end conveyor is controlled in such a manner that this conveyor is driven at a slightly higher speed than the speed of travel across the sub—floor whereas the intermediate conveyor 22 is driven at a yet higher speed to ensure that the elements are thrown as referred to in the aforegoing.

The removal of the elements is believed to continue unimpededly as long as there is no interference with the function of the blocks 49 as regards their abutment against the sub-floor and their penetration by means of their tips underneath the edge of the element. However, obstructions may occur in the sub-floor, e.g. in the form of thresholds, edgings or depressions. Should the block encounter an obstruction of this kind the block will be urged to perform a rotary movement (clockwise as seen in Fig. 3) as a result of abutment of its tip whereas the arm 47 will pivot somewhat upwards, whereby the block will turn over 180 . Since the block is syrrπetrical, it will assume a new position which is completely equivalent to the previous one and may continue its operation. The block so to say rolls over the obstacle. In order for this to happen a force of abutment against the outer tip of the block necessarily must produce a moment force in the clockwise direction. This is achieved in that its pivot shaft 48 is positioned above the line passing through the pivot shaft 46 of the arm 47 and the position of the top when the bottom face of the block rests against the sub-floor. This line is illustrated in double dotted lines in Fig. 3 and is indicated by numeral reference 57. In case a block should slide onto the upper face of the relevant element as a result of unevenness

in the sub-floor surface of because of a faulty element edge, the block and the arm will slide gradually further upwards on the element during the continued removal operation, whereby the arm 47 will be pivoted backwards to the previously mentioned position of deposition (see the dash and dot line in Fig. 3) . Thus, it will not prevent further removal. Owing to the provision of several arms (cf. Fig. 1) the latter will ensure the continued removal. Should several arms be pivoted backwards in the manner indicated they obviously must be re-set which is effected by folding them downwards manually.

As appears from the aforegoing, the ends of the arms 47 form the points of deposition and removal, respectively. Consequently, this point is the point of contact between the machine and the sub-floor.

The machine may be modified within the scope of the appended claims without departure from the inventive idea. For instance, it is not necessary to provide two conveyors between the magazine and the point of deposition/removal but one single conveyor will suffice. However, by dividing the conveyor into two sections it is possible to provide the control described in the aforegoing, which is obtained as a result of the different speeds of the two conveyors. In addition, the division of the machine into two sections makes it more easy to collapse into the position of transportation. The magazine could be arranged in another manner than that shown and so could its discharge and reception functions.