FR2976273A1 - Machine for fusion and/or automatic division of palletized loads in logistics warehouse, has load gripping device placed at level of conveyor section, and platform varying vertical distance between gripping device and conveyor section - Google Patents

Abstract

The machine has a supply conveyor (3) for supply of palletized loads and pallets to a fusion/division station (2), and a delivery conveyor (5) for evacuation of fused and/or divided palletized loads from the fusion/division station. The fusion/division station includes a conveyor section (14) having a low position in which the supply conveyor and the delivery conveyor are connected. A load gripping device (16) is installed at the level of the conveyor section, and a platform (15) varies a vertical distance between the gripping device and the conveyor section. An independent claim is also included for a method for automatic division of palletized loads by a machine.

Description

FIELD OF THE INVENTION The present invention relates to the handling of palletized loads, and more particularly to the carrying out of one or both of the following operations: the automatic division of palletized loads high in at least two palletised loads of lower heights, - automatic melting of at least two palletized loads of low heights into a palletized load of greater height. The division of palletized loads is particularly useful after destocking or receipt of these loads, for example in logistics warehouses. The merging of palletized loads is used in particular before transporting or storing these charges. These operations of merger or division of palletized loads are generally performed manually. They require a large workforce and generate repetitive tasks that are difficult for the operators. There are machines performing these operations in a more or less automated way, but these are generally designed for handling loads whose characteristics are constant. They are not suitable for handling loads whose characteristics are variable, for example in size, weight, rigidity or mechanical resistance to crushing. The invention proposes a solution for the handling of palletized loads allowing the automatic division or fusion of charges whose characteristics are variable. For this purpose, the subject of the invention is a machine for automatically melting and / or dividing palletised loads, characterized in that it comprises: a melting / dividing station; a conveyor for bringing palletised loads and pallets to this station; a conveyor for discharging fused and / or divided charges from said station, the melting / dividing station comprising: a conveyor section comprising a low position in which it connects the supply conveyor and the evacuation conveyor; load sensing means arranged vertically above the conveyor section; and - displacement means adapted to vary the vertical distance between the gripping means and the conveyor section.

2

According to other features of this machine: - said gripping means are disposed at a predetermined level, and in that said moving means are adapted to move the conveyor section between its lower position and a plurality of high positions; - the machine includes:. means for marking the base of each load to be grasped by the gripping means; and. detection means associated with these marking means, integral height of the input means; the input means comprise: two opposing jaws; . means for moving the two jaws towards each other and away from each other; and. flaps articulated on the jaws and adapted to come into contact with the two faces of the load to be grasped parallel to the displacement of the jaws; the jaws comprise means of opening in two stages, namely a partial opening of a few centimeters to guide the load during its descent, then total opening of the jaws in order to clear all the space necessary for the next pallet introduction; each flap comprises an articulated arm on the associated jaw, and an articulated support pad at the free end of the arm; the direction of displacement of the jaws is perpendicular to the central axis of the supply and discharge conveyors; the jaws and / or the flaps comprise an extended and flexible upper zone in order to better match the shape of the palletised loads, and a lower, lower, more rigid zone for materializing the level of separation of the loads; - The extended and flexible upper zone consists of a rigid outer face, a flexible film in contact with the palletized loads, and a compressible element between the rigid face and the film; - The gripping means comprise at least one movable safety member adapted to be placed below the input load to prevent the possible collapse of the seized load; the movable safety device is actuated with an approach stroke with a low thrust force, to check the absence of obstacles beneath the seized load, and then with considerable effort, after this check, for the continuation final of his race as well as during his withdrawal. The invention also relates to a method of automatic division of palletized loads of great height into at least two palletized loads of lower heights, by means of a machine as defined above, characterized in that it comprises the following automated steps: (a) introduction and positioning of the palletized load in the melting / dividing station, (b) identification of the desired level of load separation, (c) adjustment of the vertical distance between the gripping means and the conveyor section so that this distance causes the gripping means facing the upper part to separate from the load; (d) seizure of this upper part; (e) returning said vertical distance to its initial value; (f) evacuation of the palletized lower portion of the load; (g) introduction and positioning of a pallet in the fusion / division station; (h) bringing the pallet just below or in contact with the upper part of the load; (i) release of the upper part of the load; and (j) evacuation of the palletized upper part of the load. The invention also relates to a method of automatically melting at least two palletized loads of low heights into a palletized load of greater height, by means of a machine as defined above, characterized in that comprises the following automated steps: (a) introducing and positioning a first palletized load in the melting / dividing station, (b) adjusting the vertical distance between the gripping means and the conveyor section so that this distance brings the input means next to the base of the first load; (c) seizure of this first charge; (d) returning said vertical distance to its initial value; (e) evacuation of the pallet from the first load; (f) introducing and positioning a second palletized load in the fusion / division station; (g) feeding the second load just below or in contact with the first load; (h) releasing the first charge; (i) optionally adding one or more other palletized loads by repeating steps (b) to (k); and (j) evacuation of the pallet carrying the fused charge.

Embodiments of the invention will now be described with reference to the accompanying drawings, in no way limiting. On these drawings; - Figure 1 is a schematic top view of a machine according to the invention; FIGS. 2A to 2M schematically illustrate, in side view, the operation of the machine, at the location of the melting / dividing station, for the division of a palletized load; - Figures 3A and 3B show schematically, in top view, the gripping device; and - Figure 4 shows on a larger scale a vertical section of a jaw.

The machine shown diagrammatically in FIG. 1 comprises: a zone 1 for automatic feeding in empty pallets; a station 2 for the merger / division of palletized loads; a conveyor 3 supply station 2; a conveyor 4 for transferring empty pallets from zone 1 to conveyor 3; and a conveyor 5 for discharging the palletized loads from the station 2. The supply zone 1 comprises: a table 6 for empty pallet stack removal, provided with transfer rollers 7; a station 8 unstacking one by one empty pallets; and - a controlled roller conveyor 9, of horizontal central axis XX, which extends from the table 6 to the station 8. The station 8 is essentially formed of a controlled roller conveyor section 10 located in the extension of the conveyor 9 and above which is a seizure mechanism schematized in 11.

The transfer conveyor 4 is a chain conveyor YY axis perpendicular to the axis XX, which comprises two loops 12 each of which extends in a vertical plane located between two rollers of the conveyor section 10 and between two rollers of the conveyor 3. The conveyor 4 is carried by a movable frame vertically between low and high positions, in which the upper strand of the loops 12 is respectively below and above the upper generatrix of the rollers of the conveyor section 10 and the Conveyor 3. The conveyor 3 has a central axis X'-X 'parallel to the central axis XX. It is fed on the one hand in empty pallets by the transfer conveyor 4, on the other hand in palletized loads to be divided or fused by means of an upstream table 13 similar to the table 6. The fusion / division station 2 comprises a section of controlled roller conveyor 14 mounted in a nacelle 15 movable vertically. In the lower position of the nacelle, illustrated in Figure 2A, the section 14 is at the same level as the conveyors 3 and 5 and connects them. The nacelle 15 may be elevated to any controlled height, as will be described later. The station 2 also comprises a load-catching device 16 (FIGS. 2A to 2M and 3A, 3B) disposed at a predetermined substantial height H above the level of the conveyors 3 and 5. The device 16 comprises two horizontally movable jaws 17. towards each other and away from each other. Each jaw is contained in a vertical plane parallel to the axis X'-X '. The plane of the jaws was rotated 90 ° in Figures 2A to 2M for clarity of the drawing. As shown in FIG. 4, each jaw comprises an expanded and flexible upper zone 18 in order to better match the shape of the palletized loads, and a lower rigid lower zone 19 to form the level of separation of the charges. The outer face 20 of the jaw is for example made of steel. The face 21 of the upper zone in contact with the palletized loads is for example made of a braided fabric, and between the fabric 21 and the outer face 20 is arranged a compressible element 22, for example synthetic foam. The lower zone 19 more rigid comprises for example a polyurethane rubber heel 19A. According to another embodiment of the invention, the compressible element 22 is a fixed-pressure or pressure-controlled air cushion. As shown in Figures 3A and 3B, on each vertical edge of each jaw 17 is articulated an L-shaped holding arm 17A. At the end of each arm is articulated a bearing pad 17B. All axes of articulation are vertical. Each set 17A, 17B forms a holding flap of seized products.

The device 16 also comprises a securing device consisting of two horizontal drawers 23 arranged along the lower edge of the jaws. These drawers slide in their plane, towards each other and away from each other. The evacuation conveyor 5 terminates at a shipping table 5A with 5 controlled rollers. The operation of the machine for dividing a palletized load will now be described. The loading and distribution of the empty pallets are carried out by means of the following steps. An Automatic Guided 10 Vehicle (AGV), or an operator, feeds station 8 by depositing a stack of empty pallets on the table 6. Once the dispensing cycle is complete, the stack is transferred by the rollers 7 on the conveyor 9. As soon as the station 8 is empty, the stack is transferred inside thereof. After referencing the stack, two arms of the device 11 come to grip the stack at the second pallet. The assembly rises to allow the remaining pallet 24 15 to evacuate via the conveyor 4. Once the empty pallet is evacuated, the stack is lowered again at the level of the conveyor section 10, released and then taken up at the level of the second pallet of the stack to run a new unstacking cycle. Station 8 thus cycles to the last pallet of the stack. He is then ready to treat a new pile. The loading and distribution of the loaded pallets are carried out by means of the following steps. Prior to loading, it is necessary to indicate the height at which the palletised load 25 to be shortened must be shortened. For this, a bar code label 25A is glued to one of the two faces of the load 25 parallel to the direction of travel. For convenience for the drawings, the tag 25A is shown in FIG. 2A on one side of the load perpendicular to the direction of movement of the pallet. The label 25A is located at the bottom of the box where the topping is to be done. A laser detector 25B placed on the gripper 16 makes it possible to detect the position of the labels and thus informs the machine on the level of topping of the load. Other marking and reading devices are obviously possible, for example by means of self-adhesive reflectors. For supplying the conveyor 3, an AGV or an operator deposits the palletized load 25 on the table 13. At the end of the dispensing cycle, the AGV automatically transmits the type of the load deposited, previously entered in the AGV, to the control system. If the supply is manual, the operator enters the information on a desk at his disposal. Once this type is known, the load 25 is moved on the conveyor 3 as soon as it is available. A width gauge check is made during the transfer to this conveyor to verify that the load is compatible with the automatic station 2. As soon as the station 2 is available, the load 25 is transferred into it by means of the conveyor 3 It is then followed by an empty pallet 24 from station 8 (Fig. 2H to 2M). A pallet control (empty or full) is provided at the entrance of the station 2. In parallel with the physical transfer of the pallet, a follow-up of the type associated with said pallet is performed in order to restore the output of the conveyor 5 the type of the pallet to be evacuated by AGVs or operators.

The topping or automatic division of the pallets is carried out by following the following steps, shown schematically in FIGS. 2A to 2M. As shown in FIG. 2A, the pallet load 25 (pallet mother) arriving from the conveyor 3 is placed in the center of the station 2 by means of the conveyor section 14. Two cells (not shown) to verify the proper centering of the pallet. The load 25 comprises a pallet 27 on which are placed products 28 located in the upper part of the load 25 and intended to be moved on an empty pallet 24, and products 29 located in the lower part of the load and intended to remain on the pallet 27. The boundary between the products 28 and 29 constitutes the head height of the load 25. As shown in FIG. 2B, the load 25 is then mounted via the nacelle 15, not shown in this figure, until detection by the detector 25B of the bar code label 25A indicating the height of topping. In the event of non-detection, an overtravel fault is triggered, stopping the current cycle. As shown in FIG. 2C, the upper part of the load is then maintained by a pressure exerted laterally by the jaws 17. Then, the hinged flaps 17A, 17B (FIGS 3A and 3B) maintain the upper part of the load by a pressure exerted according to a direction perpendicular to that of the jaws. The flaps are shown in the open position in FIG. 3A, for introducing or evacuating a load, and in the closed position in FIG. 3B, for the maintenance of products 28. The axis of rotation of the arms 17A allows the establishment and release of the flaps, while the axis of rotation of the pads 17B allows the pads to match the shape of the products 28. The jaws and the flaps are for example actuated by pneumatic cylinders. As shown in FIG. 2D, the pallet 27 is slightly lowered by the nacelle to create a space between the products 28 held by the jaws and the products 29 supported by the pallet 27.

The control of the presence of this space between the products is ensured by the two drawers 23. As shown in FIGS. 2E and 2F, these two drawers are placed on either side of the pallet and constitute movable safety members coming to be placed below the upper part of the load when it is separated from the lower part, so to prevent the eventual collapse of the upper part. As can be seen in FIG. 2E, the drawers 23 are initially actuated with a low thrust force approach stroke to control the absence of obstacles below the upper load (probe function). After this check, if the space is free, the drawers 23 are then actuated with great effort for the final continuation of their stroke as shown in FIG. 2 F. This makes it possible to straighten the possibly curved bottom of the upper part of the load.

As shown in FIG. 2G, the pallet 27 is then brought back by the nacelle at the level of the conveyor 14 and is evacuated towards the conveyor 5. As shown in FIG. 2H, a new empty pallet 24, arriving from the conveyor 4, is placed at the center of the station 2 by means of the conveyors 3 and 14. As shown in FIG. 21, the empty pallet is raised by the nacelle 15 near the products 28. The positioning of the empty pallet is for example provided by an encoder to know the level where the nacelle is. As shown in FIG. 2J, the drawers 23 are open to free the space under the products. When removed, the drawers are operated with great effort to not be blocked when the load weighs on them following a subsidence of the products. The presence of the pallet 24 close to the products 28 makes it possible to retain them in case of collapse. As shown in FIG. 2K, the pallet 24 is again raised by the nacelle to the immediate vicinity of the products 28, or in contact therewith, in order to limit the drop height of the products on the pallet after opening the jaws. As shown in FIG. 2L, the jaws 17, and the flaps 17A, 17B, are open, which releases the products 28 on the pallet 24. The opening of the jaws is performed in two stages: opening of only a few centimeters for a time short enough to guide the products during their descent and prevent them from becoming destabilized, then total opening of the jaws in order to clear all the space necessary for the next pallet introduction.

As shown in FIG. 2M, the pallet 24, on which the products 28 rest, is then lowered by the nacelle 15 at the conveyor 5 before being evacuated by it to the table 5A, where it is supported by an AGV or a operator. In the example described above, the palletized feedstock is distributed over two pallets. Depending on requirements, a similar mode of operation of the machine allows the load to be spread over three or more pallets. In this case, a bar code label 25A is pre-glued at each line of separation of the products. The first stages of operation of the machine are the same as that described above, up to that shown in FIG. 21, the device 16 retaining the two upper partial loads. The pallet 24 is then lowered by the nacelle until detection by the optical detector 25B of the label 25A placed highest on the starting load. The jaws 17 and the flaps 17A, 17B are closed so as to maintain the upper part of the load. The lower part is evacuated from the station 2 while a new empty pallet 24 is put in place to receive the upper part of the load according to the steps of Figs. 21 to 2M. We will now describe the operation of the machine for the melting of two palletized loads on a single pallet. AGVs, or an operator, feed the loading station by successively depositing the two palletized loads 25 to merge on the table 6. The first load 25 deposited is that which includes the products which will be found in the upper part of the fused pallet. After each removal, the AGV automatically transmits the type of pallet deposited to the control system, or the operator enters the information on the desk at his disposal. Once the known type, the load is transferred to the conveyor 3 as soon as it is available. A width gauge check is made when transferring to this conveyor to verify that the load is compatible with automatic operation of the machine. The load then waits for station 2 to be available before it is transferred into it by means of roller conveyors 3 and 14. Parallel to the physical transfer of the pallet, a follow-up of the type associated with said load is carried out, this is to return the line type of the pallet to be evacuated by the AGV or the operators.

Automatic pallet melting is performed as follows. The first load 25 arriving from the conveyor 3 is placed in the center of the station 2 by means of the conveyor 14. The load 25 is then mounted by means of the nacelle 15, until the pallet 27 is at the level of the optical detector 25B . All the products carried by this pallet are maintained by a pressure exerted laterally by the jaws 17 and then by the flaps 17A, 17B. The pallet is lowered slightly by the basket to create a space between the products held by the jaws and the pallet. After checking the presence of this space, the two drawers 23 are placed below the products to prevent their eventual collapse. The drawers 23 are initially actuated with an approach stroke with low thrust, to control the absence of obstacles below the products. After this check, if the space is free, the drawers 23 are then actuated with great effort for the final pursuit of their race. The pallet 27 is then brought back by the nacelle at the level of the conveyor 5 and is evacuated towards it.

The second palletized load 25, arriving from the conveyor 3, is placed in the center of the station 2 by means of the conveyor 14. It is then lifted by the platform 15 until the upper limit of the products is in the vicinity of the drawers 23. The stop of lifting of the platform can be controlled by the detection by the optical detector 25B of a bar code label 25A previously glued on the upper end of the load. In another example, the height of the load has been previously transmitted to the control system of the machine, and the stop of the lifting results from the information delivered by an encoder to know the level where the nacelle is. The drawers 23 are open in order to free the space under the products of the first load 25. When they are withdrawn, the drawers are actuated with great effort so as not to be blocked when the load weighs on them as a result of a slump some products. The presence of the products of the second load 25 near the products of the first load makes it possible to retain the latter in the event of collapse. The second pallet 27 is raised by the nacelle until the upper limit of the products it carries is in the immediate vicinity of the products of the first load, in order to limit the height of their fall after opening. jaws. The jaws 17 are open, which allows to release the upper products. The pallet, on which the products of the two loads now rest, is then lowered by the nacelle at the level of the conveyor 5 before being evacuated by it to the table 5A, where it is taken over by an AGV or a operator.

In the example described above, the fusion is carried out between two palletized loads. Depending on requirements, a similar mode of operation of the machine can merge three or more palletized loads. Alternatively, the machine may further comprise a separate line placed downstream of the station 2 for the evacuation and automatic stacking of empty pallets after melting palletized loads. The palletized loads supported by the machine can contain a wide variety of products, including flowers, vegetables, etc., placed in different types of containers, for example cardboard, wood or plastic. In addition, the pallets may contain only one type of products or consist of a stack of different products. The mechanical strength of the products, and in particular their resistance to crushing, varies according to their nature and the type of container used. According to an exemplary embodiment of the invention, the force exerted by the jaws 17 for the maintenance of the products is adjusted according to the nature of the products present between the jaws. The pressure exerted by the flaps 17A, 17B can also be adapted to the nature of the products. The adjustment of the force is for example obtained by varying the supply pressure of the pneumatic cylinders. With jaws 17 actuated by pneumatic cylinders, it is advantageous to drive the cylinders by means of air distributors called "closed center". Thus, the pressure is maintained in the cylinder in the event of pressure drop in the compressed air supply circuit, in particular due to a power failure. This keeps in place the products present between the jaws thus avoiding their fall. In addition, the compressed air supply circuit jaw cylinders 17 can stop the supply of compressed air when the target pressure for a good maintenance of the products is reached. Thus, if the products tend to crash and in case of prolonged shutdown, the products are not likely to crash gradually, because the air pressure in the cylinders drops with the decline in the resistance exerted by the products on the jaws, which nevertheless remain permanently in contact with the products. The speed of rise and descent of the nacelle is advantageously adapted to the operation performed. Thus, the rise of the nacelle with a complete load, as shown in FIG.

2B, for example is performed at low speed, while the rise of an empty pallet, as shown in FIG. 21, is performed at fast speed. Controlled roller conveyors are an effective means of handling pallets. Any other handling means can be envisaged, for example belt conveyors. The type of means may also be differentiated between the input section, the output section and the merge / division station. In an economic variant of the machine, reduced productivity, it does not include the zone 1 and the conveyor 4. The palletized loads and empty pallets are all introduced on the table 13.

Claims (1)

CLAIMS1.- A machine for automatically melting and / or dividing palletized loads, characterized in that it comprises: - a melting / dividing station (2); a conveyor (3) for feeding palletized loads and pallets to this station; a conveyor (5) for discharging fused and / or divided charges from said station, the melting / dividing station comprising: a conveyor section (14) comprising a low position in which it connects the supply conveyor and the evacuation conveyor; load sensing means (16) disposed vertically above the conveyor section; and - displacement means (15) adapted to vary the vertical distance between the gripping means and the conveyor section. 2. Machine according to claim 1, characterized in that said gripping means (16) are arranged at a predetermined level, and in that said moving means (15) are adapted to move the conveyor section (14) between its low position and a plurality of high positions. 3.- Machine according to claim 1 or 2, characterized in that it comprises: - means (25A) for marking the base of each load to be grasped by the gripping means (16); and detection means (25B) associated with these marking means, integral at height with the gripping means (16). 4. Machine according to any one of claims 1 to 3, characterized in that the gripping means (16) comprise: - two opposing jaws (17); means for moving the two jaws towards each other and away from each other; and - flaps (17A, 17B) articulated on the jaws and adapted to come into contact with the two faces of the load to be grasped parallel to the displacement of the jaws. 5.- Machine according to claim 4, characterized in that the jaws (17) comprise opening means in two stages, namely a partial opening of a few centimeters to guide the load during its descent, then total opening of the jaws to clear all the space needed for the next pallet introduction. 6.- machine according to claim 4 or 5, characterized in that each flap (17A, 17B) comprises an arm (17A) articulated on the associated jaw, and a bearing pad (17B) articulated to the free end of the arms. 7. Machine according to any one of claims 4 to 6, characterized in that the direction of movement of the jaws (17) is perpendicular to the central axis (XX, X'-X ') of the conveyors (3, 5 ) of supply and evacuation. 8.- Machine according to any one of claims 4 to 7, characterized in that the jaws (17) and / or the flaps (17A, 17B) comprise an upper zone (18) extended and flexible to fit the best shape palletized loads, and a lower, lower, rigid area (19) for materializing the level of separation of the charges. 9. Machine according to claim 8, characterized in that the upper zone (18) extended and flexible consists of a rigid outer face (20), a flexible film (21) in contact with the palletized loads, and a compressible element (22) between the rigid face and the film. 10. Machine according to any one of claims 1 to 9, characterized in that the gripping means (16) comprise at least one movable safety member (23) adapted to be placed below the load entered to to prevent the eventual collapse of the seized load. 11.- Machine according to claim 10, characterized in that the mobile safety member (23) is actuated with a low thrust force approach stroke, to control the absence of obstacles below the load seizure, then with great effort, after this control, for the final pursuit of his race as well as during his withdrawal. 12. A method of automatic division of palletized loads of high height into at least two palletized loads of lower heights, by means of a machine according to any one of claims 1 to 11, characterized in that it comprises the steps automated systems: (a) introduction and positioning of the palletized load in the melting / dividing station (2), (b) identification of the desired level of load separation, (c) adjustment of the vertical distance between the gripping means (16) and the conveyor section (14) for this distance causes the gripping means facing the upper part to separate (28) from the load; (d) seizure of this upper part; (E) returning said vertical distance to its initial value; (f) evacuation of the palletized lower portion of the load; (g) introducing and positioning a pallet (24) into the melting / dividing station; (h) feeding the pallet just below or in contact with the upper gripping portion (28) of the load; (i) release of the upper part of the load; and (j) evacuation of the palletized upper part of the load. 13. A method of automatic melting of at least two palletized loads of low heights into a palletized load of greater height, by means of a machine according to any one of claims 1 to 11, characterized in that it comprises the following automated steps: (a) introduction and positioning of a first palletized load in the melting / dividing station (2), (b) adjustment of the vertical distance between the gripping means (16) and the conveyor section ( 14) for this distance brings the gripping means facing the base of the first load; (c) seizure of this first charge; (d) returning said vertical distance to its initial value; (e) evacuation of the pallet from the first load; (f) introducing and positioning a second palletized load in the fusion / division station; (g) feeding the second load just below or in contact with the first load; (h) releasing the first charge; (i) optionally adding one or more other palletized loads by repeating steps (b) to (k); and (j) evacuation of the pallet carrying the fused charge.