CH679032A5 - Distributeur automatique de sacs. - Google Patents

Description

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Description

The present invention relates to the distribution systems for plastic bags used in food retail outlets.

The use of polyethylene bags has become widespread within large distribution areas, requiring an additional operation of distribution of these bags by the cashier. The quantity of bags distributed per day being very important, it was wise to invent an automatic device to carry out this distribution. On the other hand, the generalization of fast-reading boxes by scanner has led to a significant increase in the throughput of these boxes, leaving no time for the customer to store the products purchased in the bags. This last must, in fact, open the bag whose walls are often glued, hold the open bag with one hand and load his purchases with the other hand. It was therefore judicious to bring to these problems a subjugation by the use of an apparatus automatically distributing the bags, but also capable of offering to the customers the open bags and of keeping them open during the loading time, and this at loading height.

at present, there is no device offering the possibility of distributing these bags and offering them open to customers.

The apparatus, object of the present invention, is composed:

- a storage system "A" for bags in the form of a roll;

- a spacing system "B" of the walls of the by suction of these walls;

- a gripping system "C" by the bag handles, ensuring the driving of the bag strip, the opening of the bags and their maintenance in a position of use for the operator;

- a bag detachment system "D" by retaining the movement of the bag strip.

Fig. 1 shows a general arrangement of the invention and its systems, marked from A to D.

Figs. 2 to 6 show two examples of the spacer system "B".

Figs. 7 and 8 describe the possible kinematics of the gripping system "C", using linear, curvilinear or rotary movements.

Fig. 9 shows a gripping system "C" produced by linear movements.

Figs. 10 to 13 show a gripping system "C" produced by curvilinear movements.

Figs. 14 to 16 show a gripping system "C" produced by rotary movements.

Figs. 17 and 18 show a detachment system "D" operating by adhesion.

Figs. 19 to 23 show a detachment system "D" operating by obstacle.

Figs. 24 to 26 show the possible applications of the invention.

The bag storage system "A" uses a known principle which is generally used for small bags without handles: The bags are interconnected and detachable by traction. They form a continuous strip presented in a roll 1 (fig. 1). The roller is arranged on an axis 2 and unwinds freely by pulling on the strip 3.

The bag wall spacing system "B" comprises two plates 4 and 5 arranged on each side of the strip 3 so that this strip can move freely between the plates 4 and 5 with reduced play. On each plate 4 and 5 a bell 6 seals with a fan 7, so that the operation of the fan 7 causes a depression inside the bell 6. Each plate 4 and 5 is pierced with holes intended for cause the suction of one of the walls of the bag against each plate and the maintenance against the latter when the fan 7 is running. Fig. 2 shows a top view of the plate 4. The holes 8 are distributed on the plate so as to ensure a distribution according to the shape of the bag and more or less pronounced depending on the places of the bag where it is necessary to have a correct maintenance . The plates 4 and 5 are movable in such a way that their displacement causes the walls of the bag to separate when they are held by suction against the plates. The operation of spacing the walls of the bag being intended for gripping this bag, it must be done at the level of the handles of the bag, as shown by the distribution of the holes in FIG. 2. In the embodiments shown of the invention (FIGS. 3 to 6), the plates 4 and 5 are articulated around two axes 9 and 10, arranged perpendicular to the travel of the strip 3 and as close to it as possible. . Of course, other technically known embodiments can be used to guide the mobility of the plates 4 and 5 and in particular solutions without an axis. The movement of plates 4 and 5 can be controlled in different ways. In one embodiment of the invention, according to FIGS. 3 and 4, the plates 4 and 5 are separated by the known mechanism of the “connecting rod-crank” type. An electric geared motor 11 drives, by successive U-turns, a rotary plate 12, comprising an eccentric drive axis. Two connecting rods 13 connect the axis of the plate to the bells 6. FIG. 3 shows the system in the rest position. The plates 4 and 5 are against the strip of bags 3. The operation of the fans 7 causes the suction of the walls of a bag against the plates 4 and 5. The U-turn of the plate 12 causes the spacing of the plates 4 and 5 and therefore that of the walls of the bag (fig. 4). In another embodiment of the invention (FIGS. 5 and 6), the plates 4 and 5 are connected to the bells 6 by bellows 14 made, for example, of canvas or of elastic plastic film. They are always articulated around the axes 10, perpendicular to the travel of the strip of bags 3. FIG. 5 shows the system in the rest position. The natural elasticity of the bellows keeps the plates 4 and 5 against the strip of bags 3. The starting of the fans 7 causes, firstly the immediate aspiration of the walls of the bag against the plates 4 and 5, and then the displacement of the plates towards the bells 6. The displacement of the plates is done with a slight delay time compared to the suction of the walls of the bag because of the volume of the bellows 14 to be emptied. In

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in all cases, the goal is to slightly spread the walls of the bag at the handles so as to be able to penetrate the gripping fingers 15 by the side of the handles.

The gripping system “C” ensures the introduction of the fingers 15 into the handles of the bag, the movement of this bag towards the position of use, and the spacing of the fingers 15 to present this bag open to the user, and this at loading height. On each side of the bag, at the handles half-opened by the spacing system "B" (fig. 7 and 8), the gripping system "C" has two fingers 15, parallel and arranged one against the other, and then introduces them into the handles of the bag. The gripping system then ensures the transfer of the bag to the position of use for customers. During the transfer operation, the gripping system ensures a different movement of the two fingers on the same side, so that they separate from each other, in order to open the bag as much as possible possible and authorized by the shape of the bag handles. To perform the functions of the “C” gripping system, it is possible to use various industrially known technical solutions, based on components ensuring linear, curvilinear or rotary displacements. Figs. 7 and 8 show two examples of technically feasible operating cycles for carrying out the necessary movements. In these two examples, the choice of location of the members related to a “vertical” arrangement of the spacing system “B”, with the simple aim of exposing here a maximum of technical embodiments of the invention. Fig. 7 shows an operating cycle of the “rectangular” type, using four rectilinear movements. The movement AB ensures the introduction of the two pairs of fingers 15 into each bag handle. The movement BC ensures the routing of the bag to the position of use. Note that the spacing of the paths traveled allows the bag to be opened to the maximum. The CD movement allows the fingers to be withdrawn and the DA movement ends the cycle by bringing the fingers back to the start and rest position. In the representation of fig. 7, the movements used are rectilinear, but it is also possible to use curvilinear movements. Fig. 8 shows an example of a “triangular” type operating cycle, with two curvilinear movements and a rectilinear movement. To obtain the spacing of the fingers, the two movements AC can be carried out, for example, by rotation around two different axes, or by rotation around the same axis but with different angles of rotation. In the case of a "triangular" cycle, the fingers are removed during the return stroke GA to the starting and resting point. Fig. 9 shows a technical embodiment corresponding to the cycle of FIG. 7. A fixed slide 16 allows the transverse guiding of two carriages 17. Two electric jacks 18 ensure the lateral movement of the carriages 17. This arrangement makes it possible to carry out the two strokes AB and CD of FIG. 7, corresponding to the introduction of the fingers into the handles of the bag and their removal. On each carriage two bars 19 are arranged in a vertical plane and ensure the guiding of two slides 20 each supporting a finger 15. The arrangement of the bars 19 is such that when the slides are in the low position 20A, the fingers 15 are joined , and that when the slides are in the high position 20B, the fingers 15 are sufficiently apart to open the bag. An electric actuator 21, integral with each carriage 17 ensures, by means of billets 22, the raising and lowering of the slides 20, that is to say the movements BC and DA of FIG. 7. Of course, conventional electronic regulation ensures, with the help of commercially available limit switch control systems, the general operating cycle of the assembly.

Figs. 10,11,12 and 13 show another embodiment of the invention using only curvilinear movements and a "rectangular" cycle. A chassis 23 supports two fixed ball joints 24. On each of the ball joints 24 a double arm can oscillate in all directions. These double arms consist of a main arm 25 and a secondary arm 26 articulated on the first, around the ball 24, and in such a way that it always remains in the same plane as the main arm 25. Each arm 25 and 26 supports a gripping finger 15 disposed on an identical radius. Opposite the fingers 15, each arm is equipped with a ball joint 27, the ball joint of the arm 26 being disposed on a shorter radius than for the ball joint of the arm 25. A gear motor 28 drives by successive U-turns a crank 29 carrying an axis 30. Two billets 31 and 32 connect the arm ball joints 27 and the crank axis 30. At rest (fig. 11), the arrangement of the elements is such that the two fingers 15 are one near each other and at the handles of the bag ajar by the spacer system "B". When the gear motor 28 makes a U-turn, the traction on the billets 31 and

32 drives the arms 25 and 26 differently since the action radii of the ball joints 27 are different. The secondary arm 26 moves more than the main arm 25. A judicious study of the different radii makes it possible to obtain the spacing of the fingers corresponding to the opening of the bags, as shown in FIG. 13 of the device in the position of use by customers. On the other hand, each double arm is equipped with another ball joint 33, situated on an axis perpendicular to the plane of the arms and passing through the axis of the main ball joint 24. An electric geared motor 34 drives by successive U-turns a plate 35 equipped with an axis 36. Two connecting rods 37 of identical length, connect the ball joints

33 to axis 36. Figs. 10 and 12 show the two positions obtained at each half-turn of the gear motor 35: the fingers are spaced apart in FIG. 10 and introduced into the handles of the bag in FIG. 12. The combination of the two geared motors makes it possible to produce a “rectangular” cycle. FIGS. 10, 11 show the device in the rest position. The fingers are spread apart and located at the level of the bag handles. The gear motor 35 then makes a half-turn (stroke AB in fig. 7), to introduce the fingers into the handles of the bag (fig. 12). Then the gearmotor 28 in turn performs a half-turn (stroke BC in fig. 7). Arms 25 and 26 are

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then raised to the position of use and the fingers 15 are separated to open the bag as much as possible (fig. 13). To return to the rest position, the geared motor 35 performs a new U-turn causing the fingers to withdraw (fig. 10), and the geared motor 28 also performs a new U-turn, bringing the arms back to the low position (fig. 11). Here too, the regulation of the operating cycle is entrusted to a simple and conventional electronic card, the end positions of the geared motors being ensured by contactors, detectors or commercial cells.

In the exemplary embodiments of the invention described so far, the gripping system always returns from (a position of use to the rest position by making the reverse movements (CD and DA of FIG. 7, CA of the Fig. 8). This return operation represents 50% of the operating time of the device. It represents a precious waste of time and an unnecessary source of wear of the device. In particular in the case of curvilinear movements, it is therefore interesting to extend these movements after the final position of use to close them completely and thus return to the starting position. The use of rotary movements, multiple or submultiples of 360 ", allows to realize rotary cycles like that shown in fig 14. The cycle always remains "rectangular", but has the advantage of always having the same direction of rotation, and symmetry in the vertical plane. This symmetry also allows the use of two pr diametrically opposed hension. The embodiment of the invention shown in figs. 15 and 16 shows an application of this type of operation, with a double gripping system ("G1" and "C2"). A frame 38 (fig. 15) supports two fixed bearings 39. These two bearings allow two shafts 40 to rotate coaxially. A gear motor 41 drives, thanks to two small pulleys 42 and two positive drive belts 43 (toothed belts, chains), two large pulleys 44 integral with the shafts 40. The shafts 40 in turn drive two supports 45 On each support, four ball joints 46 allow articulation in all directions of two arms 47 for the first gripping system "C1", and two opposite arms 48 for the second gripping system "C2". Each arm is provided with a gripping finger 15. To limit and impose the necessary deflections of each arm 47 and 48, it is necessary to provide two additional supports or guides arranged in two different planes. To do this, a first maintenance is provided by each connecting rod 49 articulated between the fixed bearing 39 and the ball joint 50 secured to the arm 47. By eccentricating the articulation of the connecting rod 49 around the fixed bearing 39, it can be seen that the position of the arms is different between the "C1" gripping system and the "C2" gripping system. It is possible, by judiciously choosing the value of the eccentric "E" (FIG. 16), ensuring the bringing together of the fingers in the low position "C2", and the suitable spacing of the fingers in the high position "C1". It is further noted that when the support 45 makes a U-turn, the arms 48 move apart and come to take the "C1" position, and that the arms 47 shave and come to take the "C2" position. A second holding of the arms 47 is provided by a guide, using the lateral rollers 51. Each arm is in fact provided with a roller 51, relatively distant from the plane of the arm and flowing in a groove 52 or 53, integral with the chassis 38. FIG. 16 shows the detail of the grooves 52 and 53. In order for the two arms 47 or 48 to be actuated at the same time, it is necessary to circulate each roller 51 of the same gripping system in its own groove. A groove 52 is therefore used for the left roller of the "Cl" system and its opposite of the "C2" system, and a groove 53 for the right roller of the "Cl" system and its opposite of the "C2" system. Lafig. 16 represents the system “C1” in the position of use by the customers and therefore in the position of introduction into your bag handles. When the “C1” system starts to rotate, the XY ramps act on the rollers 51, direct them towards the center, and consequently, cause the arms 47 to pivot, and the fingers to withdraw. Similarly, before the system “C2” arrives in the low position, the UV ramps direct the rollers 51 towards the outside of the system and cause the arms 48 to pivot and the fingers to be inserted into the bag handles. For the finger insertion operation to be rapid, it is advisable to place the UV ramps just before the low position and to tilt the ramps sharply so that this operation is sufficiently abrupt. In this way, the rotational movement of the fingers is negligible compared to the size of the opening of the handles. Between the ramps, the groove portions are circular to keep the arms and fingers in the same lateral position during rotation. Fig. 15 shows the general arrangement of the device in the rest position. In this representation, the spacing system "B" is horizontal and in the lower part of the device. Note the advantage of this type of embodiment: when the device is at rest, a bag is ready for use, that is to say, at loading height, opened by the gripping system "C1", and a another bag, still connected to the strip 3 is already ajar by the spacing system "B", with the fingers 15 already introduced into the handles by the gripping system "C2". It is enough to make a double turn to the double gripping system for a second bag to be offered open to customers. This arrangement therefore makes it possible to reduce the idle operating times and to reduce the wear of the apparatus by approximately 50%.

The bag detachment system "D" is intended to brake the bag strip 3 during the transfer of the last bag by the gripping system "C" to the position of use. The bags being detachable by simple pulling thanks to a rupture line between each bag, the fact of temporarily blocking the running of the band during the transfer operation, causes the rupture of this band and the detachment of a bag. Several technological solutions, industrially known, can be used to perform this operation. They basically use two principles

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different: grip and obstacle. Figs. 17 and 18 show an exemplary embodiment using the principle of adhesion. A roller 54 is arranged perpendicular to the direction of travel of the strip 3. To obtain maximum adhesion, this roller is coated with rubber. The strip of bags 3 circulates around this roller. To further increase the adhesion of the strip on the roller 54, the winding angle of this strip is as large as possible. Optionally, a small pressure roller 55 exerts an additional force and makes it possible to have a maximum winding angle. This small roller 55 can, for example be mounted on an articulated arm 56, stretched by a spring 57. The roller 54 is integral with an axis 58 which can rotate freely between two bearings 59, integral with the chassis 60. To temporarily ensure locking in rotation of the roller 54, a rotation braking device 61, fixed on the chassis 60, is centered on the axis 58 of which it is integral in rotation. This braking device is commonly sold in the industry as a mechanical construction component. These are in particular electromagnetic clutch-disc brakes or toothed clutch-brakes (brands WARNER or TOURCO, for example). When the gripping system "C" drives the bag strip 3, the clutch-brake 61 is actuated at the precise moment or the bag seized is evacuated from the spacer system "B". In this way, a second bag is in the correct position in the spacer system "A". The action of the clutch-brake will then be released when the spacer system "B" comes into action and holds the bag. Fig. 17 shows the moment of rupture of the bag strip 3. The distance FG represents the length "L" of a bag. For the system to function correctly, the diameter of the roller 54 is such that the limit of the bag next to "H" is not yet engaged around the roller 54. FIGS. 19, 20 and 21 represent an embodiment of the detachment system “D” using the principle of the obstacle. The strip of bags 3 having alveoli at the level of the handles and between them, it suffices to introduce a hook or any other mechanical part which obstructs, in this alveolus, at the opportune moment of movement of the strip to cause the stop of this strip and the detachment of the first bag. The embodiment shown uses a double hook 62, articulated on a fixed axis 63 and controlled by an electromagnet 64 or any other movement system known industrially. The hook 62 is positioned just upstream of the spacer system "B". Fig. 19 represents the moment when the gripping system "C" has just grasped the waiting bag, ajar by the spacing system "B". The hook 62 is raised by the electromagnet 64 and allows the strip of bags to pass through. As in the adhesion system, the electromagnet is actuated in the other direction at the precise moment when the next bag is in the correct position in the spacer system "B". Fig. 20 and its top view 21 represent the moment when the hook 62 is lowered into the pocket of a bag. The strip of bags 3 is then stopped, and the first bag is detached from this strip by pulling the fingers 15 of the gripping system "C". The hook 62 will be raised after the spacer system “B” is in action, that is to say when the new bag is held against the plates of this system. Another embodiment of the detachment system "D" is shown in FIGS. 22 and 23. This particular embodiment of the invention uses the principle of the obstacle and aims to integrate it into the spacing system "B", using its vacuum energy. This embodiment incorporates the bellows system described on page 3 and shown in FIGS. 5 and 6. We find the honeycombed plates 4 and 5 ensuring the suction of the walls of the bag and the bellows 14. For clarity of the drawings, the fans 7 have not been shown. Only the hole 65 remains for housing the fan on the bell 6. The bell 6 of the upper bellows has a prominence intended to allow the movement of another bellows system located inside the first. The honeycomb plate 5 is cut into a U shape to receive another plate 66 articulated on the same axis 10 as the plate 5. A small bellows 67 provides sealing between the plate 5 and the plate 66 by allowing the latter to travel . The plate 66 has a hook 68 to act as an obstacle, coming to be housed in the cells of the bags. The lower honeycomb plate 4 has a hollow 69 intended to receive the hook 68 when the latter is lowered. Fig. 22 represents the position where the fingers 15 come inside the bag handles (cycle AB). The fans are in action and provide a vacuum inside the bellows. The plates 4 and 5 are therefore spaced apart and likewise, the plate 66 is attracted towards the bottom of the bell 6, causing the hook 68 to be raised and the bag to be released. When the gripping system “C” drives the bag by its fingers 15, the fans 7 are then cut. But since it takes a while to fill the bellows with air, the hook 68 is released after the bag is driven. Fig. 23 represents the position where the bandage 3 strikes the hook 68, then in the low position. The first bag is already driven by the gripping system and the next bag is in the correct position in the spacer system "B". As a result, the rupture of the strip 3 occurs and the first bag is detached. When the fans are again actuated, the walls of the new bag will be separated by the plates 4 and 5. Similarly, the plate 66 will be raised, releasing the hook 68 from the cell of the new bag.

Figs. 24 and 25 show an industrial application of the invention. Fig. 24 shows an embodiment according to a standalone version of the device, as it can be achieved at present, by placing itself next to the checkout counters of the stores. Fig. 25 shows a future embodiment of the invention with integration into the checkout unit. Fig. 26 shows the detail of the internal arrangement of the elements for the example chosen. A piece of furniture 70, made of sheet metal and serving as a frame, includes a storage system "A", a spacing system "B", a double gripping system "C", and a detachment system "D". A disc 71 fixed on the support 45 and rotating with the latter, protects the

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gripping system mechanism leaving only the fingers 15 visible on the outside. The device is completely open on the front face, between the gripping systems. This provision allows the User to take out the loaded bags without having to lift them. A cover 72 located in the bottom of the opening protects the detachment system and the spacing system. It also allows, by its slope, to evacuate to the outside the objects that could fall during the loading operation. The cover 72 is articulated around an axis 73 and can be raised to allow access to the interior in order to be able to carry out maintenance and loading of the rollers. In addition to the conventional end-of-travel control or presence detection devices necessary to carry out the operating cycle, the automatic starting of the device is ensured by a photoelectric cell 74. This cell is placed in the axis of the bag offered, preferably upwards, and checks for the presence of a bag offered to customers. In this way, the use of the device becomes very simple and completely automatic. When he crosses the checkout counter, the customer finds an open bag at his disposal. He then fills this bag with his purchases, without having to hold the bag and using both hands. When it has finished, it removes the bag from the device and thereby causes cell 74 to be triggered and the device to start up. Another bag automatically appears a few seconds later. In the example shown, the operating cycle is as follows:

- In the rest position, a bag is offered to customers, another bag is in position in the spacing system, with the fingers 15 of the gripping system inserted. The fans are in service and the brake cut.

- Removal of the free bag causes the engine to start and the second bag to drive. The fans are off. The brake remains off.

- The movement of the gripping system activates a detector. The brake is applied and causes the bag to detach. The fans remain off. The engine remains in operation.

- The movement of the gripping system activates another detector. The engine stops by positioning the open bag in the use position. The fans are turned on and the third bag is ajar. The brake is released.

- The cycle starts again with each bag removal.

Claims (13)

Claims 1. Device for the automatic distribution of plastic bags or similar material, of the type with handles, presented in a strip and detachable by traction, characterized in that it is composed: - a storage system (A) for bags in the form of a roll; - a spacing system (B) of the walls of the bags by suction from these walls; - a gripping system (C) by the bag handles, ensuring the training of the bag strip, opening the bags and keeping them in a position of use for the operator; - a bag detachment system (D) by retaining the movement of the bag strip. 2. Device according to claim 1, characterized in that the spacing system (B) of the bag walls is composed of two plates (4, 5) pierced with holes, arranged face to face with a slight clearance between them allowing circulation of the strip (3) of bags, and one or two air extraction systems (7), fan type, ensuring a vacuum on either side of the plates (4,5). 3. Device according to claim 2, characterized in that a mechanical system (10,12,13) controlled by an electric servo member (11) or other ensures the spacing of the plates. 4. Device according to claim 2, characterized in that each pierced plate (4, 5) is one of the two faces of a bellows (14), that this pierced plate is movable, that the other face of the bellows is fixed and that the fan or fans (7) exert a vacuum inside each bellows (14) ensuring the adhesion of the bag walls against the pierced plates (4, 5) and the movement of these plates by closing the bellows (14). 5. Device according to claim 1, characterized in that the gripping system (C) is composed of two pairs of movable fingers (15), at the rate of one pair per bag handle, and a mechanical motorized system d 'servo ensuring the introduction of these fingers into the bag handles, the drive of the bag by the fingers (15), and the spacing of the fingers (15) of each pair to open the bag. 6. Device according to claim 5, characterized in that the mechanical servo system consists of carriages (20) sliding on straight rails (19), or arms (25, 26) articulated around one or more axes , or a composition of these systems. 7. Device according to claim 5, characterized in that each finger (15) is part of an articulated arm (25, 26) and that your four arms form a rotary assembly around a single axis (24). 8. Device according to claim 7, characterized in that an eccentric (E) disposed on the single axis of rotation (39) of the assembly provides control of the spacing of each pair of fingers (15). 9. Device according to claim 7, characterized in that each arm (47) has a roller (51) and that one or more fixed raceways (52, 53) guide the rollers, the inclination of the arms and thereby the introduction of each pair of fingers into the bag handles. 10. Device according to claim 7, or according to claim 7, 8 and 9, characterized in that the gripping device (G) is double by comprising two sets of four arms (47) diametrically opposed. 11. Device according to claim 1, characterized in that the detachment system (D) is composed of one or more rollers (54, 55) ensuring the adhesion of the strip of bags and a braking system (61 ) in rotation ensuring the locking of a roller (54). 5 10 15 20 25 30 35 40 45 50 55 60 65 11 CH679 032 A5 12. Device according to claim 1, characterized in that the detachment system (D) is composed of a movable hook (62) obstructing between the bags and controlled by a motorized servo mechanism (64). 13. Device according to claim 1 and 4, characterized in that the detachment system (D) is composed of a hook (68) obstructing between the bags, that this hook is fixed on the movable wall of a bellows ( 67) located inside one of the bellows (14) of the spacing system (D), and that the vacuum provided by the fan controls the closing of this bellows (67) and the reievage of this hook (68) . 5 10 15 20 25 30 35 40 45 50 55 60 65 7