DE29812545U1 - Unstacking device - Google Patents

Description

TIEDTKE — BÜHLING pj'KJ£ils[E' %* ^.PARTNER _(CbR)

&Ggr; Tiedtke - Bühling - Kinne, POB 20 19 18, D - 80019 Munich "I Patent attorneys / representatives at the EPO'

Dipl.-Ing. Harro Tiedtke * Dipl.-Chem. Gerhard Bühling * Dipl.-Ing. Reinhard Kinne * Dipl.-Ing. Hans-Bernd Pellmann * Dipl.-Ing. Klaus Grams * Dipl.-Biol. Dr. Annette Link Dipl.-Ing. Aurel Vollnhals * Dipl.-Ing. Thomas J.A. Leson * Dipl.-Ing. Hans-Ludwig Trösch * Dipl.-Ing. Dr. Georgi Chivarov * Dipl.-Ing. Matthias Grill * Dipl.-Ing. Alexander Kühn * Dipl.-Chem. Dr. Andreas Oser * Dipl.-Ing. Rainer Böckelen * Bavariaring 4, D-80336 Munich

July 14, 1998

EN 21983

WVG Kainz GmbH

83052 Bruckmühl / Germany

"Destacking device"

Telephone: 089 - 544690

Fax(G3): 089-532611 Fax(G4): 089 - 5329095 postoffice@tbk- patent.com

Deutsche Bank (Munich) Account 286 1060 (BU 700 70010) Dresdner Bank (Munich) Account 3939 844 (bank code 700 800 00) Postbank (Munich) Account 670 - 43 - 804 (bank code 700 100 80) Dai-Ichi-Kangyo Bank (Munich) Account 51 042 (bank code 700 207 00) Sanwa Bank (Düsseldorf) Account 500 047 (bank code 301 307 00)

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Description

The invention relates to a destacking device for stackable transport boxes with a handle opening. 5

Transport boxes, which usually have a standardized size, are increasingly replacing cardboard as a packaging material. Such transport boxes are used in particular in the food industry, as these transport boxes also represent an alternative to coated cardboard in terms of hygiene. In these transport boxes, which are usually made of plastic in various standard sizes, not only are larger containers assembled ready for shipping to retailers, but these boxes are also increasingly being used in manufacturing and food processing, replacing the special containers previously used there.

For such use in the production process, the transport boxes must always be available in sufficient numbers to cover, i.e. buffer, any discontinuous need for transport boxes in production and/or packaging. Usually, the transport boxes are stacked in buffer warehouses and retrieved when needed.

'25 In order to introduce the transport crates into the production process individually, it is necessary to separate them, i.e. to unstack them and place them one after the other on a conveyor belt or the like.

For this purpose, stacking robots are known from the state of the art, which lift the individual transport boxes from a stack and place them on a conveyor belt. However, such a procedure has the disadvantage that as the stack height decreases and the conveyor belt is arranged at the maximum stack height, the travel paths of the robot's gripper arm become very large, so that unstacking can become very time-consuming.

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Furthermore, a device for stacking and unstacking transport boxes is known from the prior art according to DE-C2-195 40 147, in which a stack of transport boxes is raised by means of a lifting floor, held at this height with a holding device, a new transport box is pushed under the stack and the stack is then lowered onto this transport box. With this device, the transport boxes stacked in the stacking device can be unstacked again by reversing the stacking process. However, with this device, the time for unstacking is correspondingly extended due to the two-fold movement of the lifting floor. Furthermore, the transport boxes are often required on a conveyor belt arranged at a height, since they are often conveyed through production by simple gravity drive.

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In contrast, the object of the invention is to create a destacking device that enables rapid destacking of transport boxes.

This object is achieved with a destacking device with the features of claim 1. According to the invention, a destacking device for stackable transport boxes with a handle opening has a removal latch that can be moved reciprocally parallel to a box bottom of the topmost box of a stack of boxes, which latch grasps the box on the inside by means of an inclined surface formed on the latch at the handle opening and pulls it off the stack while lifting it.

The solution according to the invention provides a removal latch that can be arranged inside a transport box. The latch has an inclined surface that is aligned with the handle opening of the transport box. If the latch is now moved towards the outside of the box, the inclined surface of the latch engages with the handle opening, with the upper edge of the handle opening coming to rest on the inclined surface of the latch. Due to the resistance of the uppermost transport box,

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port box on its stack, the inclined surface slides further into the handle opening, whereby the inclined surface and the edge of the handle opening together form a wedge-shaped thrust mechanism which lifts the box and thus releases it from the stack. This engagement can either be through the interaction of a bead on the bottom of the top box with the upper edge of the next box or a simple frictional engagement between the two boxes. If the removal latch is now moved further away from the stack, it takes the box with it and pulls it off the stack.

According to an advantageous embodiment, the removal latch is designed in such a way that when it is inserted into the box it can be moved against the box wall and in doing so it folds out of the way of the box edge. If the latch is now moved in the opposite direction, it remains in the folded-out position, i.e. it locks in this direction. This means that a box arranged in the removal position can be removed by inserting the removal latch in an evasive manner and then pulling it off with the latch locked in the opposite direction.

According to an advantageous embodiment of the destacking device, it has a lifting floor for lifting the stack of boxes so that the top box of the stack is always in the removal position. In this way, a stack is pushed from below as soon as the top box is removed from the stack. The previously described foldable design of the removal latch makes it possible to carry out the insertion movement of the removal latch and the lifting of the stack at the same time, so that very fast destacking is possible. As an alternative, it is possible to move the destacking device relative to the stack so that the removal latch is opposite the top box of the stack. In this case, the lifting floor can be dispensed with and a conveyor belt can be connected to the destacking device.

In the previously mentioned advantageous design of the destacking device with a lifting floor, a simple roller conveyor can be used to remove the box removed in the removal position from the removal position and introduce it into the production process. This roller conveyor is preferably inclined downwards so that the box runs down the roller conveyor following gravity. In this arrangement, the removal latch can preferably be guided in a sliding manner on a stationary removal arm so that very few mechanically moving parts are required. This stationary position can also be designed to be manually adjustable so that an adjustment to a suitable stack height can be easily carried out.

The number of moving parts can be reduced by connecting the removal latch to a pneumatic linear motor or any other linear drive that moves the removal latch reciprocally.

Furthermore, the destacking device can be provided with a control device that controls the relative position of the removal latch to the top box in the stack by detecting the top edge of the top box. In this way, boxes of different heights and with handle openings arranged at the same height can also be destacked in mixed operation, since the positional relationship between the removal latch and the handle opening can always be easily maintained by the control device. This is particularly advantageous for so-called Euro boxes, which are available with the same length and width dimensions and can be stacked in three different heights. The detection of the top edge of the top box can be carried out in a particularly simple way without contact using a light barrier.

Further advantageous embodiments of the invention are governed by the remaining subclaims.

The invention is explained in more detail below using a preferred embodiment with reference to the drawing. In it:

Fig. 1 is an overview drawing of a buffer storage with an attached destacking device;

Fig. 2 is an enlarged side view of the destacking device with the removal latch positioned in the top transport box;
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Fig. 3 is an enlarged side view similar to Fig. 2, showing the removal process of the uppermost box in more detail;

Fig. 4 is an enlarged section of Fig. 2 to illustrate the stacking engagement between the topmost box and the following box; and

Fig. 5 is an enlarged partial view illustrating a folding movement of a removal latch.

Fig. 1 shows a side view of a buffer warehouse in which transport boxes designated E2 are stored in the form of stacks 1. On the right-hand side in Fig. 1, a destacking device with guides 4 for the stack to be destacked, a roller conveyor 2, and a destacking device 3 is shown. The roller conveyor 2 is followed by a conveyor belt (only indicated) that serves to further convey the destacked, individual transport boxes. Furthermore, in Fig. 1, the top box of the stack to be destacked is designated 11. A lifting floor (not shown) is arranged below the stack to be destacked, which raises the stack of boxes by one box height when the top box is removed. In Fig. 1 it can be seen that the box arranged under the top box 11 is already approaching the removal position by pushing up the stack, so that a removal latch 31 can already move towards a box again after the box 11 has been placed on the roller conveyor 2.

which then reaches the top position. This results in a very dense destacking operation.

In Fig. 2, the upper right section of Fig. 1 is shown enlarged at an earlier stage. According to Fig. 2, the destacking device 3 has the removal latch 31 with an inclined surface 34 attached to it. The removal latch 31 is arranged so that it can pivot about the axis of rotation 33, so that when moving in the direction of arrow A, it can pivotally avoid the right side wall of the top box 11 of the stack 1 in Fig. 2. To remove the top box 11, the removal latch can be moved in the direction of arrow B. For this purpose, the removal latch 31 is arranged so that it can move on the removal arm 32. The removal latch 31' arranged at the right end of the removal arm 32 in Fig. 2 is the removal latch 31 in its right end position, while 31 shows the removal latch in its left end position. As can also be seen in Fig. 2, guides 4 are provided to guide the box stack 1 while it is lifted by a lifting floor (not shown).

In connection with Fig. 5, the transfer of the removal latch 31 into the position shown in Fig. 2 is now explained. In Fig. 5, the removal latch 31 is already shown in its final position. The removal latch is moved along the removal arm 32 in the direction of arrow A. When it comes into contact with the edge of a box of an uppermost box 11 (see Fig. 2), the removal latch 31 pivots about the pivot point 33 in the direction of arrow S in Fig. 5. When the removal latch 31 has passed the edge of the box, it pivots back about the pivot point 33 into its position shown in Fig. 5 or Fig. 2. In the simplest case, the removal latch 31 can pivot back into its starting position by gravity. It is possible to support the return swing movement of the removal pawl 31 by means of a spring preload by means of a spring (not shown). This can be particularly advantageous when high cycle times occur, so that rocking of the pawl after the deflection is suppressed.

A stop 35 in Fig. 5 is designed on the removal latch in such a way that the latch can pivot in the direction S shown in Fig. 5, but the opposite direction is blocked beyond the position shown in Fig. 5. Consequently, the latch can pass the edge of the box in one direction, but not in the other direction.

The removal of the box is now explained in more detail with reference to Fig. 3 and 4. As shown in Fig. 4, the removal latch 31 is arranged inside the top box 11 of the stack to be unstacked. In this state, the inclined surface 34 of the removal latch 31 is opposite a handle opening 111 of the top box 11. The boxes 11 and 12 stacked on top of one another to form a stack are in engagement via a bead 113 in the bottom of the top box 111 and the upper edge 122 of the following box 12. To remove this engagement, as shown in Fig. 3, the inclined surface 34 now enters the handle opening 111 of the top box 11, whereby when the removal latch 31 moves in the direction of arrow B, the inclined surface slides off the upper edge of the handle opening 111 and lifts the box 11. This releases the aforementioned engagement between the bead 113 and the upper edge 122, so that the box can be easily lifted off and moved in the direction of arrow B. In the end position of the travel path of the removal latch 31, which is shown in Fig. 3 with a broken line, the removed box 11 has a sufficient distance from the roller conveyor 2. When the tipping point is exceeded, i.e. the tipping point is formed by the upper edge 122 of the following box 12, the top box tips downwards on the inclined surface 34 while the handle opening 111 of the top box 11 slides off, where it is caught and passed on by the rollers 22 of the roller conveyor 2. The box 12 is then moved to the location of the box 11 and the removal process begins again after the removal latch 31 has been transferred into the interior of the box 12. This is conveniently done as before with reference to the

Fig. 5 was explained. However, it is also possible to make the removal latch rigid. In this case, the lifting of the stack and the insertion of the removal latch 31 into the topmost box of the stack are coordinated so that the removal latch is first moved to its starting position (end position on the stack side) and the stack of boxes is then lifted. In this way, the removal latch reaches the inside of the topmost box from above without having to pass directly through the box wall. It should be noted, however, that the evasive latch and the simultaneous lifting of the stack of boxes enable a very tight cycle frequency and thus ensure a very high destacking speed.

A control device (not shown) for controlling the movement of the lifting floor or the lifting of the stack preferably detects the upper edge of the uppermost box 11, designated 112 in Fig. 4. In the predominantly used Euro transport boxes, whose length and width dimensions are always the same, but whose height can vary, the distance between the uppermost box edge 112 and the handle opening 111 is also standardized. In this way, because the control device detects the upper edge 112 of the uppermost box 11, boxes with different heights can also be mixed and destacked without changing the destacking device.

Claims (11)

1. Destacking device for stackable transport boxes (11, 12) with a handle opening (111), with a parallel to a box bottom of a respective top box (11) of a 25 crate stack (1) reciprocally movable removal latch (31), which grasps the crate (11) on the inside by means of an inclined surface (34) formed on the latch (31) at the handle opening (111) and lifts it from the stack (1) deducts. 2. Destacking device according to claim 1, characterized in that the removal latch (31) when inserted into the topmost box (11) of a stack of boxes (1) deflects the box wall by folding (S) and in the opposite direction 35 blocks. 3. Destacking device according to claim 1 or 2, characterized by a lifting floor for lifting the stack of boxes (1) in a guide (4) assigned to the lifting floor in order to bring the topmost box (11) of the stack of boxes (1) into a removal position. Telephone: 089 - 544690 Fax(G3): 089 - 532611 Fax(G4): 089 - 5329095 postoffice @ tbk- patent.com Deutsche Bank (Munich) Account 286 1060 (bank code 700 700 10) Dresdner Bank (Munich) Account 3939 844 (bank code 700 800 00) Posttiank (Munich) Account 670 - 43 - 804 (bank code 700 100 80) Dai-Ichi-Kangyo Bank (Munich) Account S1 042 (bank code 700 207 00) Sanwa Bank (Düsseldorf) Account 500 047 (bank code 301 307 00) 2, ·· 1 4. Destacking device according to claim 1, 2 or 3, characterized by a roller conveyor (2) assigned to the removal position in order to remove the destacked box (11) from the removal position. 5. Destacking device according to claim 4, characterized in that the roller conveyor (2) is inclined downwards. 6. Destacking device according to one of the preceding claims, characterized in that the removal latch (31) is slidably guided on a stationary removal arm (32). 7. Destacking device according to one of the preceding claims, characterized in that the removal latch (31) is pre-tensioned by a spring into its folded-out removal position for box removal. 8. Destacking device according to one of the preceding Claims, characterized in that the removal pawl (31) is connected to a linear motor. 9. Destacking device according to one of the preceding claims, characterized in that the removal latch (31) is connected to a pressure medium-operated piston/cylinder arrangement. 10. Destacking device according to one of the preceding claims, characterized by a control device which controls the lifting floor in order to align the upper edge (112) of the uppermost box (11) of the stack (1) in the removal position. 11. Destacking device according to claim 10, characterized in that the control device has a light barrier for detecting the upper edge (112) of the uppermost box (11).