MACHINE FOR MANUFACTURING DISPOSABLE CUPS

Technical field

[01] The present invention relates to a machine for manufacturing disposable cups and the like.

Prior art

[02] The use of disposable cups intended to contain both hot and cold drinks, commonly known as paper cups, is known in various sectors. Paper cups are generally made from a blank element of a suitable sheet material, folded in a slightly conical shape to form the side wall of the cup and sealed by a circular bottom.

[03] The use of different materials is known for manufacturing paper cups, in general depending on the use, in particular whether they are intended to contain hot drinks or cold drinks. For example, the use of cups in cellulose pulp, capable of resisting to a temperature of 70°C, or alternatively, for lower temperatures, cups of biodegradable bioplastic of the lactic acid or PLA type is known; as well as cups in laminates of paper plastic, consisting of a sheet of cardboard coated inside with a PLA film are known.

[04] Currently, the paper cups are manufactured by automatic machines operating with intermittent movement. Said automatic machines are equipped with one or more wheel- or star-shaped parts operated in stepwise rotation to bring in sequence the single blank elements at a plurality of operating stations.

[05] Automatic machines for manufacturing disposable cups are illustrated for example in patent documents US 8,939,187 and US 10,035,321. U.S. 1 ,819,318 discloses a further example of an automatic machine for manufacturing disposable cups.

[06] The intermittent operation of the aforementioned machines imposes an obvious limitation on their operating speed and consequently on the achievable productivity. This is a considerable constraint in the specific sector, as they are single-use products and therefore necessarily inexpensive, high productivity instead would be required.

[07] To increase the speed of the machine, an attempt was made to divide the most timeconsuming operative steps among a plurality of stations, in order to reduce downtime. However, this solution cannot adequately solve the problem of high productivity at economic costs. In practice, the productivity of current machines is generally around 300 cups per minute.

[08] Another drawback complained of in the sector involved is related to the fact that materials other than traditional ones are being proposed on the market for the manufacturing of disposable cups, for example materials that do not involve the use of plastic or bioplastic. Machines currently known often may not be adapted to the use of such materials.

Disclosure [09] The aim of the present invention is to solve the aforementioned problems, by devising a machine that permits to perform automatic manufacturing of paper cups with a high operating speed, in order to ensure high productivity.

[10] As part of this aim, it is a further object of the invention to provide a machine for manufacturing paper cups of any suitable sheet material.

[11] Another object of the invention is to provide a machine that permits to perform the manufacturing of paper cups provided with high resistance.

[12] A further object of the invention is to provide a machine that permits to perform the manufacturing of paper cups suitable to contain both hot and cold drinks.

[13] A still further object of the invention is to provide a machine that permits to perform the manufacturing of paper cups of proportionally low cost.

[14] Even further object of the invention is to provide a machine for manufacturing paper cups of simple construction and functional conception, with reliable operation, versatile use, as well as relatively low cost.

[15] The aforementioned objects are achieved, according to this invention, by the machine for manufacturing disposable cups according to claim 1.

[16] The disposable cups to be manufactured include a side element, obtained from a blank of sheet material folded into a conical shape, closed tightly by a circular base element.

[17] According to the present invention, the machine includes a forming wheel rotatable with continuous movement according to an axis of rotation and bearing a plurality of peripherally distributed forming assemblies comprising respectively a tubular mandrel having a profile corresponding to the cup to be made.

[18] Advantageously, the tubular mandrel is carried by a support device which may swing around an axis parallel to said axis of rotation of the forming wheel.

[19] The machine comprises first feeding means adapted to orderly collect and insert single bottom elements into corresponding forming assemblies of said forming wheel.

[20] Preferably, said first feeding means comprises a shearing member adapted to cut in sequence said single bottom elements from a strip of material wound in a reel; an annular drawing die forming an internal portion with a converging profile; a punch, coaxial to said shearing member, adapted to perform the drawing of said single bottom elements cut on said die from said strip of material wound in a reel and the subsequent insertion of the drawn bottom elements inside the mandrel of corresponding forming assemblies.

[21] Preferably, inside the mandrel of said forming assemblies is a pusher member, operable axially to extract the cups manufactured by the same forming assemblies.

[22] Preferably, said pusher member is provided frontally with a gripping surface connectable to suction means to retain said drawn bottom elements at the external opening of the mandrel of said forming assemblies. [23] The machine comprises second feeding means adapted to orderly collect single blanks from a store in which the same blanks are stacked and to transfer them in sequence, in an extended configuration, to the corresponding forming assemblies of said forming wheel.

[24] Advantageously, said second feeding means comprises a wheel for gripping and transferring said blanks rotatable with continuous movement according to a rotation axis parallel to said rotation axis of the forming wheel and having a plurality of peripherally distributed arms which may swing around a respective axis parallel to the axis of rotation of the same gripping and transferring wheel, said arms having at the free end a respective gripping member adapted to collect a single blank from said store and to transfer it onto one said forming assembly of the forming wheel.

[25] Said gripping member is rotatable between a first position in which it faces said single blank stacked in said store, to collect it, and a second position in which the blank collected by the gripping member is arranged at the side of said mandrel, in an extended configuration, parallel to the vertical plane of rotation of said forming wheel.

[26] According to the present invention, said gripping member has three degrees of freedom, defined by the possibility of rotation on three orthogonal axes.

[27] Preferably, heating means capable of heating at least one transverse edge of said blanks is associated with said gripping and transferring wheel of said blanks.

[28] The machine includes folding means suitable for winding into tubular form said single blanks on said mandrel of the respective forming assemblies.

[29] Preferably, said blank transferred onto said forming assembly is held on the external surface of said mandrel by means of a pressure member which is axially movable in a direction parallel to the rotation axis of said forming wheel.

[30] Preferably, said pressure member is moved by a slide associated with said mandrel support member.

[31] Preferably, said folding means comprises a pair of folding members consisting of rotatable jaws carried by said slide according to axes parallel to the axis of said mandrel.

[32] Preferably, said jaws have a semicircular working surface, for copying the external surface of said mandrel of the forming assemblies.

[33] The machine comprises welding means carried respectively by said swinging support member of said mandrel and movable in a direction radial to said mandrel for welding superimposed edges of one said single blank wound into a tubular form on the same mandrel.

[34] According to an advantageous aspect of the invention, said welding means comprises ultrasonic welding means.

[35] The machine comprises thermal welding means suitable for sealing said individual blanks to said corresponding bottom elements. [36] Preferably, said thermal welding means comprises a hot air generator adapted to heat said bottom elements held at the external opening of the mandrel of said respective forming assemblies, said hot air generator being movable on command of an actuator member carried by said swinging support member of said mandrel, on a plane radial to said forming wheel from an inactive retracted position to an active position superimposed on the bottom element associated with said blank wound into tubular form on said mandrel.

[37] The machine comprises curling means adapted to fold the bottom edge and the top edge of said side element of the cups.

[38] The machine comprises a finishing wheel rotatable with continuous movement according to a rotation axis parallel to said rotation axis of the forming wheel and bearing a plurality of peripherally distributed containers adapted to receive respectively said cups from said forming wheel.

[39] Advantageously, said containers are associated with a respective support member which may swing around an axis parallel to said axis of rotation of the finishing wheel.

[40] A pusher member is suitably housed inside the tubular shaped mandrel of said forming assemblies, operable axially to extract the cup from the forming assembly and to transfer the same cup inside a respective container of said finishing wheel.

[41] Preferably, said pusher member is provided frontally with a gripping surface connectable to suction means to retain said bottom element of the cup.

[42] The present invention also relates to a method for manufacturing disposable cups comprising the steps of a. rotating with continuous movement a forming wheel bearing a plurality of peripherally distributed forming assemblies comprising respectively a tubular-shaped mandrel having a profile corresponding to the cup to be made, carried by a support member swinging around an axis parallel to the axis of rotation of the forming wheel; b. collecting single bottom elements in an orderly manner by first feeding means and inserting them into corresponding forming assemblies of said forming wheel; c. collecting single blanks in an orderly manner by second feeding means from a store in which the same blanks are stacked and transferring them in sequence, in an extended configuration, to corresponding forming assemblies of said forming wheel; d. holding said blanks transferred, in an extended configuration, to said forming assemblies on the external surface of a corresponding mandrel by means of a respective pressing member axially movable in a direction parallel to the axis of rotation of said forming wheel; e. winding into tubular form said single blanks held on said external surface of a corresponding mandrel (13) by folding means (50) associated with said forming assemblies; f. welding superimposed edges of said blanks (20) wound into tubular form on said corresponding mandrels (13) by welding means (53) associated with said forming assemblies (12).

Description of drawings

[43] The details of the invention will become more apparent from the detailed description of a preferred embodiment of the machine for manufacturing paper cups, illustrated by way of example in the accompanying drawings, wherein:

Figure 1 shows a front view of the paper cup manufacturing machine according to the present invention;

Figure 2 shows an enlarged front view of an operative area of the machine for manufacturing paper cups;

Figures 3 - 16 respectively show detailed views of individual parts of the machine.

Description of embodiments of the invention

[44] With particular reference to these figures, the machine for manufacturing disposable cups 2, commonly known as paper cups, has been indicated in whole with the reference numeral 1 . In the context of the present invention, the expression "paper cups" means any type of disposable cups made of a cardboard-type sheet material, cellulose pulp, so-called paper plastics and the like, of known use in the considered sector.

[45] The paper cups 2 generally consist of a side element 20, obtained from a blank of said sheet material folded into a slightly conical shape, sealed by a circular bottom element 21 .

[46] The machine 1 comprises means 3 for sequentially feeding single bottoms 21 to a forming wheel 10 of the paper cups 2 and means 4 for sequentially feeding single blanks 20 to the same forming wheel 10 of the paper cups 2. The forming wheel 10 is rotatable with continuous motion, according to a horizontal axis 11 , to bring the individual blanks 20 and bottoms 21 at a plurality of operative stations where the manufacturing of the paper cups 2 is carried out. In particular, as specified below, the forming wheel 10 has a plurality of peripherally distributed forming assemblies 12 adapted to bring said blanks 20 and said bottoms 21 to said operative stations.

[47] The first feeding means 3 of the single bottoms 21 comprises a shearing member 30 adapted to cut in sequence said individual bottoms 21 from a strip of material of a special reel 22 and to deliver them to a forming assembly 12 rotatable peripherally to said forming wheel 10 (see Figures 3, 4 and 5). Each forming assembly 12 comprises a mandrel 13 of metal material having a slightly conical shape corresponding to the shape of the cup 2 to be formed. The mandrel 13 has an outwardly facing opening and a base associated with a support member 14, of substantially cylindrical shape. The outer opening has smaller diametric dimensions than the base associated with the support member 14. The support member 14 may swing around an axis 15 parallel to the axis of rotation 11 of the same forming wheel 10.

[48] The shearing member 30 is adapted to cooperate with a drawing die 31 during the step of feeding the single bottom 21 to the forming wheel 10. The die 31 consists essentially of a ring forming an inner portion having a converging profile. The reel 22 is adapted to be tightened between the external front surface of the die 31 and a special tightening member 32 in the shape of a cup. In particular, the shearing member 30 is movable alternately in an direction axial to the die 31 so as to shear a circular portion of the reel 22 intended to form a single bottom 21 of the cup 2. In a suitable phase relationship, a punch 33 is then actuated, coaxial to the shearing member 30, adapted to engage the sheared bottom 21. The movement of the piston 33 determines the drawing of the bottom 21 cut at the die 31 and the subsequent insertion of the bottom 21 embedded into the minor base of the mandrel 13. The drawing determines the formation of a peripheral edge 23 folded over the bottom 21 .

[49] A pusher member 16 is housed inside the mandrel 13, adapted to be driven axially to operate the subsequent extraction of the cup 2 from the forming assembly 12, as specified below. The pusher member 16 is provided at the front with a gripping surface connectable to the suction means to hold in abutment the bottom 21 of the cup.

[50] The second feeding means 4 of the single blanks 20 comprise a wheel 40 adapted to orderly collect said blanks 20 from a store 25 in which they are stacked and to transfer them in sequence to corresponding forming assembly 12 of the forming wheel 10.

[51] The wheel 40 for gripping and transferring the blanks 20 has a plurality of peripherally distributed arms 41 which may swing around a respective axis 42 parallel to the axis of rotation 43 of the same wheel 40 (see Figures 6 and 7). The arms 41 carry at the free end a gripping member 44 adapted to collect the blank 20 from the store 25 and to transfer it to a forming assembly 12 of the forming wheel 10.

[52] In particular, each gripping member 44 comprises a pair of suction cup members 45, suitably spaced on a stem 46, which may be sucked to grip the blank 20 to be collected and transferred. The stem 46 is rotatably supported by a sleeve 47, so as to be able to rotate angularly on its longitudinal axis 48, substantially for an amplitude of 90°. The sleeve 47 shapes the head of the arm 41 and is in turn rotatably mounted on this arm 41 according to the longitudinal axis 49 of the same arm 41 , perpendicular to the longitudinal axis 48 of the stem 46.

[53] In essence, therefore, the gripping member 44 is equipped with three degrees of freedom, defined by the possibility of rotation on the three orthogonal axes 42, 48 and 49.

[54] Thanks to this, the gripping member 44 can be moved between a first position in which the suction cup members 45 face the blank 20 stacked in the store 25, to collect it, and a second position in which the blank 20 collected from the gripping member 44 is arranged in an extended configuration beside the mandrel 13 of the forming assembly 12, parallel to the vertical plane of rotation of the forming wheel 10 (see Figures 2 and 6).

[55] The blank 20 may be held on the outer surface of the mandrel 13 of the forming assembly 12 by means of a pressing member 18 axially movable in a direction parallel to the axis of rotation 11 of the forming wheel 10 (see Figures 8 and 10) . The pressure member 18 is caused to move by a slide 19 which comes out frontally from the support member 14.

[56] Folding means 50 are associated with the slide 19 to carry out the tubular winding of the blanks 20 on the mandrel 13 of the respective forming assemblies 12. The folding means 50 comprises a pair of folding members 51 consisting of jaws rotatably carried according to axes 52 parallel to the axis of the mandrel 13. The jaws 51 have a semicircular working surface, so as to substantially copy the outer surface of the mandrel 13 of the forming assemblies 12.

[57] The folding members 51 may be operated in angular rotation in opposite directions, in a suitable phase relationship with the translation of the slide 19, between a mutually spaced position and a close position in which the jaws embrace the mandrel 13, progressively winding the blank 20 thereon (Figures 8 and 9).

[58] More precisely, during the step of winding the blank 20 on the mandrel 13, the slide 19 carrying the pressing member 18 and the folding members 51 advances in a radial direction to the same mandrel 13. While the pressing member 18 blocks the blank 20 on the mandrel 13, the synchronous rotation of the counter-rotating folding members 51 carries out the winding of the opposite edges of the blank 20 on the same mandrel 13.

[59] It should be noted that, when the winding is finished, a flap of the blank 20 is suitably superimposed for a portion thereof on the opposite flap.

[60] Welding means 53 of the superimposed flaps of the blank 20, also moved on the support member 14, is adapted to cooperate with the folding means 50. The welding means 53 is operable in a radial direction to the mandrel 13 in a diametrically opposite position with respect to the pressure member 18 (see again Figures 8 and 10).

[61] The welding means 53 can be of different types, depending on the sheet material constituting the blanks 20. In particular, it is possible to use ultrasonic welding means that allow optimal welding even of sheet materials that do not involve the use of plastic or bioplastic.

[62] During the rotation of the forming wheel 10, the folding members 51 keep the blank 20 wound in tubular form on the mandrel 13 for a time sufficient to complete the welding of the superimposed edges of the blank 20.

[63] A hot air generator 54 is also carried on the support member 14 to heat the bottom 21 to an appropriate temperature (Figures 10 and 11 ). The hot air generator 54 is movable on command of a special actuating member 55 carried by the swinging support member 14. The actuating member 55 is provided with an articulated arm 56 movable on a plane substantially radial to the forming wheel 10 to shift the hot air generator 54 from an inactive retracted position to an active position superimposed on the bottom 21 of the semi-finished product 20.

[64] The heating produced by the hot air generator 54 is able to carry out the thermal welding of the peripheral edge 23 of the bottom 21 inside the blank 20 wound on the mandrel 13.

[65] The curling of the bottom of the cup then takes place, in the sector also known as "bottom curling", by means of a curling assembly 57 acting in the axial direction to the mandrel 13 of the folding assembly 12 (Fig. 12). The curling assembly 57 comprises a first folding member 58 adapted to fold the free edge 24 of the semi-finished product 20 inwardly and a second folding member 59 adapted to head the same edge 24 of the semi-finished product 20 to the peripheral edge 23 of the bottom 21 that closes said semi-finished product 20.

[66] In particular, the first folding member 58 consists of a sprung ring internally having a flared profile able to engage the free edge 24 of the semi-finished article 20 to carry our a first folding towards the inside of the mandrel 13; the second folding member 59 consists of a piston adapted to be actuated axially to the aforementioned sprung ring to head the edge 24 of the semi-finished product 2 onto the peripheral edge 23 of the bottom 21 (see the enlarged detail of Fig. 13).

[67] The cup 2 is then transferred to a finishing wheel 60, driven in rotation in the same way with continuous movement according to an axis of rotation 61 parallel to the axis of rotation 11 of the forming wheel 10. The finishing wheel 60 has a plurality of peripherally distributed containers 62, made of metal material, adapted to bring the cups 2 to a plurality of finishing operating stations. The containers 62 are associated with a respective support member 63, which may swing according to an axis 64 parallel to the axis of rotation 61 of the same finishing wheel 60 (Fig. 14).

[68] The transfer of the cups 2 in sequence within the respective containers 62 is carried out by the axial operation of the pusher member 16, acting on the bottom 21 of the same cups.

[69] The cups 2 inserted inside the respective containers 62 are brought by the finishing wheel 60 to a station 65 for the application of a suitable lubricating substance capable of facilitating the subsequent curling step of the same cups 2. This station 65 for application of the lubricating substance essentially provides a shaped punch 66 movable in the radial direction to the finishing wheel 60 and bearing a sponge ring 67 soaked in the aforementioned lubricating substance (Fig. 15).

[70] Downstream of the station 65 for applying lubricating substance is a station 70 for curling the top of the cups 2, also known in the sector as "top curling", preferably implemented in two successive phases, substantially similar from a constructive and functional point of view. Basically, in the top curling station 70, the first and second coupling means 71 , which are adapted to grasp the upper edge of the cups 2 and to curl them outwards, act in sequence (Fig. 16).

[71] Finally, the finished cups 2 are ejected through a tubular member 8 for pneumatic transfer, operating in a known-per-se manner.

[72] The operation of the machine for manufacturing paper cups is easily understandable from the above description.

[73] In operation, the first feeding means 3 and the second feeding means 4 respectively feed in sequence the bottom elements 21 and the blanks 20 to the forming wheel 10, operated in rotation with continuous movement.

[74] In particular, the first feeding means 3 collects and orderly inserts single bottom elements 21 at the opening of the tubular mandrel 13 of corresponding forming assemblies 12 of the forming wheel 10.

[75] The shearing member 30 of the first feeding means 3 cuts in sequence the single bottoms 21 from a strip of material wound in a reel 22, clamped against the annular-shaped drawing die 31 (Figures 3 and 4). The operation of the punch 33, coaxial to the shearing member 30, draws the single bottoms 21 cut from the strip of material wound in a reel 22 at the die 31 and the subsequent insertion of the embedded bottoms 21 into the opening of the mandrel 13 of corresponding forming assembly 12 (Fig. 5).

[76] In a suitable phase relationship, the second feeding means 4 orderly collects single blanks 20 from the store 25 in which the same blanks 20 are stacked and transfers them in sequence, in an extended configuration, to the corresponding forming assemblies 12 of the forming wheel 10.

[77] The single blanks 20 are gripped by the gripping members 44 carried by the arms 41 of the gripping and transferring wheel 40, operated in rotation with continuous movement according to an axis of rotation 43 parallel to the axis of rotation 11 of the forming wheel 10.

[78] The gripping members 44 are provided with three degrees of freedom, defined by the possibility of rotation on the three orthogonal axes 42, 48 and 49.

[79] It should be noted that the gripping members 44 are operated in motion between a first position in which the suction cup members 45 face the blank 20 stacked in the store 25, to collect it, and a second position in which the blank 20 collected by the gripping member 44 is arranged in an extended configuration beside the mandrel 13 of the forming assembly 12, parallel to the vertical plane of rotation of the forming wheel 10.

[80] According to an aspect of the present invention, during the step of transferring the blanks 20 to the forming wheel 10, the forming assemblies 12 and the arms 41 of the gripping wheel 40 are swinging with respect to the same wheels 10, 40, on command of cam means not shown, so as to have zero relative velocity. In this way it is possible to transfer the blanks 20 without interrupting the continuous rotation movement of the forming wheel 10 and of the gripping and transferring wheel 40.

[81] The blanks 20 transferred in an extended configuration on the tubular mandrel 13 of the respective forming assemblies 12 are held on the external surface of this mandrel 13 by the pressure member 18, moved by the slide 19 and axially movable in a direction parallel to the rotation axis 11 of the forming wheel 10.

[82] In this configuration, the blanks 20 are engaged in succession by the folding means 50 which carries out the winding in tubular form on the mandrel 13 of the respective forming assemblies 12 (Figures 8 and 9).

[83] In particular, during the winding step, the counter-rotating bending members 51 advance, carried by the slide 19 in the direction of the mandrel 13. The synchronous rotation of the folding members 51 carries out the winding of the opposite edges of the blank 20 on the mandrel 13. When the winding is completed, a flap of the blank 20 is suitably superimposed for a portion thereof on the opposite flap.

[84] The welding means 53 is then operated in a radial direction to the mandrel 13 so as to fit into the gap left free between the free ends of the folding members 51. The welding means 53 is kept in contact under pressure with the superimposed edges of the blank 20 wound on the mandrel 13 for a time sufficient to complete the perfect welding thereof.

[85] In a suitable phase relationship, the thermal welding of the bottom elements 21 to the single blanks 20 is carried out by the operation of the hot air generator 54, carried on the same support members 14 bearing the forming assemblies 12.

[86] In particular, the hot air generator 54 is movable on command of a special actuator member 55 between an inactive retracted position and an active position superimposed on the bottom 21 of the blank 20 wound into tubular form on the mandrel 13 (Figures 10 and 11). The hot air generator 54 heats the bottom 21 to an appropriate temperature to perform the thermal sealing of the peripheral edge 23 of the bottom 21 inside the blank 20 wrapped on the mandrel 13 and previously welded.

[87] In this way, a semi-finished product consisting of a lateral element 20 is obtained, starting from the blank of sheet material folded in a slightly conical tubular shape on the mandrel 13, sealed by a bottom element 21 of circular shape.

[88] This semi-finished product is then subjected to a cup bottom curling step, by means of a heading assembly 57 acting in the axial direction to the mandrel 13 of the folding assembly 12 (Fig. 12). In particular, the curling of the bottom of the cup is performed in two steps by the first folding member 58, which folds the free edge 24 of the semi-finished product inwards, and by the second folding member 59, which heads the same edge 24 of the semi-finished product on the peripheral edge of the bottom 21 (see the enlarged detail of Fig. 13).

[89] During the step of curling the bottom of the cup, the forming assembly 12 and the curling assembly 57 are swinging, on command of cam means (not shown), so as to have zero relative velocity.

[90] The semi-finished product is then transferred to the finishing wheel 60, operated in rotation in the same way with continuous movement according to a rotation axis parallel to the rotation axis of the forming wheel 10 and having a plurality of peripherally distributed containers 62, suitable for receiving single semi-finished products in an orderly manner.

[91] To carry out the transfer to the finishing wheel 60, the semi-finished products are held at the bottom, on the inner side, by the gripping surface connected to the suction means of the pusher member 16. The axial actuation of the pusher member 16 determines the translation of the semi-finished product inside the container 62 (Fig. 14).

[92] It should be noted that the containers 62 are associated with a respective support member 63, swinging around an axis 64 parallel to the rotation axis 61 of the finishing wheel 60, so as to follow the synchronous swinging movement of the forming assembly 12.

[93] The cups 2 inserted inside the respective containers 62 are brought by the finishing wheel 60 to the station 65 for the application of a suitable lubricating substance capable of facilitating the subsequent step of top curling of the same cups 2. In the station 65 for the application of the lubricating substance a shaped punch 66 operates, movable in the radial direction of the finishing wheel 60 and carrying a sponge ring 67 soaked in the aforementioned lubricating substance (Fig. 15).

[94] Downstream of the station 65 of applying lubricating substance, the cups 2 are carried in sequence by the finishing wheel 60 to the top curling station 70. The top curling is performed in two successive steps, by activating the first and second coupling means 71 which are adapted to grip the top edge of the cups 2 and to curl them outwards (Fig. 16).

[95] Finally, the packaged cups 2 are expelled through the tubular pneumatic transfer member 8.

[96] The described machine achieves the object of manufacturing paper cups with a high operating speed, so as to ensure a correspondingly high productivity. In particular, it has been verified that the manufacturing machine according to the invention permits to reach a productivity of about 700 cups per minute.

[97] This is made possible thanks to the inventive idea of rotating the cup forming wheel with continuous movement at high speed, avoiding the stopping of the same forming wheel in the different operating stations which, in the known art, imposes inevitable limits on the machine speed. To this end, the cup-forming wheel rotates a plurality of forming assemblies comprising respectively a tubular-shaped mandrel having a profile corresponding to the cup to be made; said mandrel is associated with a support member which oscillates around an axis parallel to said axis of rotation of the forming wheel.

[98] In practice, during the active phases, the forming assemblies are swinging in synchronism with the swinging movement of the operating members acting in the different stations of the machine, so as to have zero relative velocity, for a time sufficient to complete the operation.

[99] Obviously, the high productivity so obtained allows the manufacturing of paper cups with a proportionately economic cost, in accordance with the characteristics required by a disposable product.

[100] A prerogative of the machine according to the present invention is the possibility of making paper cups of any suitable sheet material, in particular materials that do not require the use of plastic or bioplastic. The particular structure of the machine is in fact suitable for the use of ultrasonic welding means that are suitable for the use of plastic or bioplastic-free strip materials.

[101] Another advantageous aspect of the invention is the fact of having a longer time for the cup welding phases, in order to obtain a particularly effective and safe welding. The welding means is in fact carried on board the forming assemblies, so that the welding can take place during the rotation of the forming wheel that carries said forming assemblies.

[102] The machine for manufacturing paper cups described by way of example is susceptible of numerous modifications and variations according to the various requirements.

[103] For example, it is possible to provide that, in correspondence with the finishing wheel, a further side element of cardboard is associated with the side surface of the paper cups, adapted to increase the insulation when used with beverages having a high temperature or a particularly low temperature.

[104] In the practical embodiment of the invention, the materials used, as well as the shape and the dimensions, may be modified depending on needs.

[105] Should the technical features mentioned in any claim be followed by reference signs, such reference signs were included strictly with the aim of enhancing the understanding of the claims and hence they shall not be deemed restrictive in any manner whatsoever on the scope of each element identified for exemplifying purposes by such reference signs.