EP3845475A1 - Device and method for stacking folding boxes and blanks in a stacking shaft - Google Patents

Abstract

A device and a method for stacking folding box blanks in a stacking shaft are proposed, which is particularly advantageous with regard to the outlay on equipment and free configurability.

Description

The invention relates to a device and a method for stacking folding box blanks or folding box tubes in a stacking shaft, the folding box blanks being transported at high frequency in a "quasi-continuous" flow in the stacking space. There they should be piled up to form a stack before the stack is transported out of the stacking shaft in one transport direction.

From the EP 1 251 093 A2 such a device is known. The device has proven itself on the market for many years. However, the requirements for the device, in particular such a method, have increased over the last few decades. In particular, ever smaller folding boxes are in demand; As a result, the folding box blanks have also become smaller. Particularly in the case of small folding box blanks that reach the stacking space of a device for destacking at high speed, there is a risk that they will tilt when flowing into the stacking shaft and thereby cause a disruption. The reasons for this are the low mass and low mass moment of inertia of small folding box blanks.

The ones from the EP 1 251 093 A2 or B1 known device comprises, in addition to a lifting table that can be moved in the vertical direction of the stacking shaft, two temporary supports that alternately or sequentially carry the stack of folding box blanks that are being formed until a finished stack is located on a lifting table in its lowest position is transported away from the stacking shaft. Then the lifting table that has become free is moved upwards again in the vertical direction and takes over the stack that is being formed from the active temporary support.

The disadvantage of this device is that it is limited with regard to its motion sequences and thus with regard to the method it carries out. As a result is that the process of destacking cannot be adapted within the wide limits required today. In addition, the device is relatively complex, since in addition to the lifting table it requires two temporary intermediate shelves with the associated drives and a correspondingly complex control.

The invention is based on the object of providing a device and a method which makes it possible to uncouple extremely small and small folding box blanks in a process-reliable manner in the stacking shaft of a device for destacking into a stack without tilting the folding box blanks. The method according to the invention should moreover be adaptable very flexibly to different folding box blanks or folding box tubes, so that almost all shapes and sizes of folding box blanks can be stacked.

The object underlying the invention is achieved according to the invention by a device for stacking folding boxes or folding box tubes, comprising a stacking shaft, a lifting table, only one clipboard, a hold-down device, a first drive for the lifting table, a second drive for the clipboard and a third drive for the Hold-down released, the stacking shaft being delimited in a transport direction at its front end by a first stop and at its rear end by a second stop, the stacking shaft being limited downwards alternately by the lifting table and the intermediate storage The first drive is designed as a single-axis drive that controls the position of the lifting table in the stacking shaft, the second drive being designed as a two-axis drive so that it controls the position of the clipboard along a predetermined and repetitive path, and wherein the third drive is designed as a two-axis drive in such a way that it controls the position of the hold-down device along a predetermined and repetitive cyclical path.

In the device according to the invention, in contrast to the prior art cited above, only one clipboard is required, which significantly reduces the outlay on equipment. Because the device according to the invention has a two-axis drive both for the clipboard and for the hold-down device, it is possible to control the path on which the hold-down device and the clipboard move as freely as possible, so that according to the size of the folding box blanks to be stacked and their other properties, an optimal control of the paths of the clipboard and hold-down can take place. As a result, a difference in height between the upper edge of the first stop can be kept almost constant during the stacking process, regardless of whether the stack being formed is carried by the hold-down device, the intermediate shelf or the lifting table. This difference in height can also be set individually for each application; it tends to be smaller for small folding box blanks than for large folding box blanks. According to the invention, the hold-down device has two functions. It serves as a temporary clipboard and after a short time transfers this function to the actual clipboard. The "starting position" of the hold-down device is slightly below an upper edge of the first stop of the stacking shaft and moves gradually downwards, so that the upper end of the stack forming on the clipboard is always at a small and constant distance from the upper edge of the first stop of the stacking shaft is located. This ensures that the folding box blanks "flowing in" via the first stop of the stacking shaft cannot tilt and the stack is formed undisturbed. The hold-down device is then quickly moved downwards, ie in the direction of the lifting table located at the bottom of the stacking shaft. As a result, the hold-down device "transfers" the stack that is being formed to the clipboard.

As soon as the stack has been transported out of the stacking shaft on the lifting table, the lifting table moves up and takes over the stack that forms from the intermediate storage.

The hold-down device moves down so far that it compresses the (finished) stack on the lifting table. This stack is then moved out of the stacking shaft in the transport direction with the aid of conveyor belts. The hold-down follows the transport movement of the stack. This ensures that the stack leaves the stacking shaft without any problems. Then, ie when the prongs of the hold-down device have been moved completely out of the stacking shaft in the transport direction, the hold-down device moves back up into its starting position. At the same time, the new stack mentioned above is created on the clipboard.

As soon as the stack has been transported out of the stacking shaft on the lifting table, the lifting table moves up and takes over the stack that forms from the intermediate storage. The clipboard is then immediately pulled out of the stacking shaft, preferably against the direction of transport. Outside the stacking shaft, the clipboard is returned to its starting position in the direction of the Y-axis, i.e. at the desired distance from the upper edge of the first stop, before the method according to the invention starts again from the beginning.

The device according to the invention according to claim 1 enables this method to be carried out. The method is relatively simple and the requirements for the device are relatively low. Because of the two-axis drives of the hold-down device and the clipboard, the movements of the hold-down device and also the clipboard in the transport direction can be controlled independently of one another orthogonally. This makes it easier to control them and to adapt the process to different folding box blanks.

It is of course also possible that - by superimposing the control movements of the hold-down device and / or clipboard in the direction of the first axis and the second axis running orthogonally to it - the hold-down device and / or the clipboard along a freely configurable or programmable (curved or to move paths composed of straight lines. As a result, the device and the method can be adapted to a wide variety of folding box blanks.

The mutually independent movement axes of the second drive and the third drive preferably run orthogonally or parallel to a transport direction of the device. The drives or the drives of the axes of movement can for example be electrical, electromechanical, pneumatic or hydraulic. Combinations of these drives are also possible. An electromechanical drive is, for example, a drive with a toothed belt and an electric motor, which can be designed as a stepper motor or servo motor. Drives with ball screw spindles and a server motor or a stepper motor are also possible. Linear motors are also an option. Ultimately, the invention can be implemented with different drive concepts for the movement axes.

In order to ensure the transport of a finished stack that is located on the lifting table from the stacking shaft efficiently and safely, it is provided in a further advantageous embodiment of the invention that one or several conveyor belts are arranged and the lifting table is lowered so far that the stack is seated on the beginning of the conveyor belt or belts. As soon as the conveyor belt is driven, the stack is transported out of the stacking shaft.

Further advantages and advantageous embodiments of the invention can be found in the following drawing, its description and the claims. All of the features disclosed in the drawing, its description and the patent claims can be essential to the invention both individually and in any combination.

drawing

Figur 1

eine schematische und sehr stark vereinfachte, teilweise geschnittene Teil-Seitenansicht einer erfindungsgemäßen Vorrichtung;

Figur 2

eine weitere Teilansicht der erfindungsgemäßen Vorrichtung;

Figur 3

eine Synthese der Figuren 1 und 2; und

Figuren 4ff

die Interaktion der verschiedenen beweglichen Baugruppen der Vorrichtung bei der Durchführung des erfindungsgemäßen Verfahrens.

Show it:

Figure 1

a schematic and very simplified, partially sectioned partial side view of a device according to the invention;

Figure 2

a further partial view of the device according to the invention;

Figure 3

a synthesis of Figures 1 and 2 ; and

Figures 4ff

the interaction of the various movable assemblies of the device when carrying out the method according to the invention.

Description of the exemplary embodiments

In the Figure 1 is a greatly simplified side view of an embodiment of a device according to the invention for stacking shown. In the Figure 1 are - for the sake of clarity - parts of the device not shown. The device comprises a first stop 1 and a second stop 3 running parallel thereto. The stops 1, 3 are adjustable in terms of their spacing from one another, so that they can be adjusted to the length of the in Figure 1 folding box blanks, not shown, can be matched. The stack is formed between the first stop 1 and the second stop 3, as shown below on the basis of FIG Figures 4ff will be explained. The first stop 1 can be designed as a vibrating wall. The stops 1, 3 are not designed as a continuous wall, but rather they have slots through which the prongs of a hold-down device (not shown in FIG Figure 1 ) and a clipboard 15 can be moved through into the stacking shaft 5.

The stacking shaft 5 is delimited at the bottom by a transport device 7, which is designed here as a transport belt or a plurality of transport belts 9 running parallel to one another. The conveyor belts 9 run over rollers 11, only one of which is shown, and are driven via one of the rollers 11 if necessary. In the Figure 1 an X-axis and an XY-axis are entered. The origin of this coordinate system lies at 13. A transport direction T is also shown. It runs parallel to the X axis; the transport device 7 transports a stack (not shown) of folding box blanks in the direction of the transport direction T and thus also in the direction of the X-axis out of the stacking shaft 5.

There is a distance LH between the lower end of the second stop 3 and the conveyor belt 9, which is dimensioned such that even the highest stacks can be transported out of the stacking shaft 5 under the second stop 3 in the direction of the transport direction T.

In the Figure 1 a clipboard 15 is shown. The clipboard 15 comprises several fingers or prongs running parallel to one another, only one of which can be seen. The fingers protrude through slots (not visible) of the first stop 1 in the in Figure 1 position shown in the stacking shaft 5 and thus form with their upper edge a support for folding box blanks which flow into the stacking shaft 5 from the top left approximately in the direction of arrow 17.

The clipboard 15 is arranged on a first slide 17 which is arranged or guided along a linear guide in the direction of the Y-axis on a frame 19 so as to be movable. The frame 19 can be moved on a first guide rail in the direction of the X-axis. The travel of the carriage 17 in the direction of the Y-axis and of the frame 19 in the direction of the X-axis are indicated by double arrows 23, 25. The frame 19 and with it the clipboard 15 can be moved far in the direction of the negative X-axis so that the clipboard 15 is completely outside the stacking shaft 5. In the direction of the Y-axis, the travel path of the clipboard 15 or of the carriage 17 only has to be comparatively small. In practice, a travel distance of 15 or 20 cm in the direction of the Y-axis is sufficient. In order to illustrate the relations of the travel paths, the arrow 25 is significantly longer than the double arrow 23.

In the Figure 2 FIG. 10 is the same device also in the same side view as in FIG Figure 1 shown. However, the clipboard 15, the carriage 17 and the frame 19 are not shown. Rather, further components that belong to the device according to the invention are shown and are explained in detail below.

A lifting table 27 is shown in the stacking shaft 5. The lifting table 27 can, as indicated by the arrows, be moved in the direction of the Y-axis. A lowermost position of the lifting table 27 is reached when the top of the lifting table is below the conveyor belt 9 of the transport device 7. This lowest position is shown by a broken line. In order to avoid a collision of the lifting table 27 with the conveyor belt or the conveyor belts 9 running parallel to one another, the lifting table 27 is also not as continuous surface, but it has several parallel partial surfaces which are arranged and dimensioned so that these partial surfaces do not collide with the conveyor belts 9 of the transport device 7 when the lifting table 27 is lowered into the lowest position.

In the Figure 2 to the right of the second stop 3, ie outside of the stacking shaft 5, a hold-down device 29 is indicated. The hold-down device 29, like the clipboard 15, has a two-axis drive. This means that it can be moved in the direction of the Y-axis and in the direction of the X-axis via separate drives. As with the clipboard 15, these drives are not shown.

The carriages and guides to which the hold-down device 29 is attached and guided along two axes are also not shown. The arrangement of the slide, frame and guides is in principle similar to that of the clipboard 15. The hold-down device 29 is attached to a slide which is guided on a frame such that it can be displaced in the direction of the Y-axis. The frame is arranged on a further linear guide or guide rail so that it can be moved in the direction of the X-axis.

Based on the in Figure 2 position shown, the travel of the hold-down device 29 in the direction of the negative X-axis is so great that the (in Figure 2 left) end of the Hold-down 29 can be moved into the immediate vicinity of the first stop 1.

In the Figure 3 is now a synopsis of the Figures 1 and 2 shown. No new components have been added, so an explanation of the Figure 3 can be dispensed with.

In the Figures 4ff the stacking shaft and the components holding down device 29, clipboard 15 and lifting table 27 protruding into it are shown in different positions. The Figures 4ff are intended to explain the sequence of the method according to the invention.

In the Figure 4 the hold-down device 29 is retracted into the stacking shaft 5. The upper edge of the hold-down 29 is an amount .DELTA.Y below the upper edge of the first stop 1. This amount .DELTA.Y is determined depending on the size or length of the folding box blanks 31, which from the top left in the Figure 4 (see arrow 17) flow into the stacking shaft. As soon as the folding box blank 31 is positioned between the first stop 1 and the second stop 3, it sinks downwards due to the force of gravity and comes to rest on the hold-down device 29. Optionally, the folding box blank 31 can also be "pressed" downwards by a correspondingly directed air flow from a blower (not shown). In the Figure 5 a very similar situation is shown, with the difference that several folding box blanks 31 are already on the hold-down device 29. the hold-down device 29 is located opposite the Figure 4 in a slightly lowered position, so that the topmost folding box blank 31 is located below the upper edge of the first stop 1 by approximately the same amount ΔY in both figures. This is achieved by lowering the hold-down device 29 continuously or in steps. The amount by which the hold-down 29 is lowered corresponds roughly to the height of the stack of folding box blanks 31 that is being formed. In other words: whenever another folding box blank has reached the stacking shaft 5, the hold-down is lowered by an amount corresponding to the thickness of a folding box blank .

In the Figure 6 the situation is shown that the clipboard 15 moves from the left, ie in the direction of the positive X-axis, slightly below the hold-down 29 into the stacking shaft 5. The intermediate storage 15, like the hold-down device 29, has several parallel prongs which can move into the stacking shaft 5 through complementary slots in the first stop 1.

In the Figure 6 the lifting table 27 is still up. A stack 33 is present between the lifting table 27 and the hold-down device 29. The distance between the lifting table 27 and the hold-down device 29 is controlled so that the height of the Stack 33 is less than the gap LH (see Figure 1 ) between the conveyor belt 9 and the lower edge of the second stop 3. Then it is possible to move the stack 33 after the lifting table 27 (and with it the stack 3 and the hold-down device 29) has reached its lower end position (see FIG Fig. 7 ) has reached to be transported out of the stacking shaft 5 to the right.

In the Figure 7 the situation is shown that the clipboard 15 carries the stack of folding box blanks 31 that is building up. The hold-down device 29 has moved downwards and presses the stack 33 of folding box blanks together, which is located on the lifting table 27 or on the conveyor belt 9. In the in Figure 7 As shown in the position of the hold-down device 29, the stack 33 is compressed by the hold-down device 29 to such an extent that it can be transported out of the stacking shaft to the right with the aid of the conveyor belt 9 or conveyor belts 9 without colliding with the lower edge of the second stop 3.

The stack 33 is transported out of the stacking shaft 5 by appropriately controlling the drive of the conveyor belt 9 and the hold-down device 29. As a result, the stack 33 on the conveyor belt 9 and the hold-down device 29 are synchronized in the transport direction T (to the right in FIG Figure 7 ) is moved in the direction of the positive X-axis, so that the stack is pressed together by the hold-down 29 even during transport out of the stacking shaft 5. The movement of the conveyor belt 9 and the hold-down device 29 takes place at the same speed, so that the stack 33 is not shifted or changed in any other way when it is transported out of the stacking shaft.

As soon as the stack 33 has been transported out of the stacking shaft 5, the lifting table 27 and the hold-down device 29 move upwards. The hold-down device 29 moves outside of the stacking shaft 5 upwards. The lifting table 27 moves upwards within the stacking shaft 5. This situation is in the Figure 8 indicated.

The lifting table 27 moves to just below the clipboard 15, so that when the clipboard 15, as in FIG Figure 9 shown, is pulled out of the stacking shaft 5 in the direction of the negative X-axis, the stack 33 being formed lands on the lifting table 27 and is carried by it.
As long as the stack 33 is being carried by the lifting table 27, the holding-down device 29 and the intermediate storage device 15 move back into the starting positions, ie the holding-down device 29 has the same height as in FIG Figure 4 and the clipboard 15 has the same height as in the Figure 7 shown.

From the synopsis or the sequence of Figures 4 to 9 the method according to the invention and its advantages become clear. These consist in that the distance ΔY from the upper edge of the first stop 1 is always constant. This distance .DELTA.Y can according to the requirements of the Set and individually configured on a case-by-case basis.

In addition, it is possible to precisely control the paths of the hold-down device 29 and the intermediate storage device 15 using the two-axis drives of the intermediate depository 15 and the hold-down device 29 and to carry out a sequence of the various movements coordinated with the lifting table 27.

The various drives are controlled via a control device (not shown) that coordinates and controls or regulates the various movements of the lifting table 27, drive 7, hold-down device 29 and clipboard 15.

List of reference symbols

1

first stop

3

second stop

5

Stacking shaft

7th

Transport device

9

Conveyor belt

11

role

13th

Origin of the coordinate system

15th

Clipboard

17th

first sledge

19th

frame

21

first guide rail

23, 25

Double arrows

27

Lift table

29

Hold-down

31

Folding box cut

33

stack

Claims (8)

Device for destacking folding box blanks (31) or folding box tubes comprising a stacking shaft (5), a lifting table (27), an intermediate tray (15), a hold-down device (29), a control device, a first drive for the lifting table (27), a second Drive for the clipboard (15), and a third drive for the hold-down device (29), the stacking shaft (5) in a transport direction (T) at its front end by a first stop (1) and at its rear end by a second Stop (3) is limited, wherein the stacking shaft (5) is limited downwards alternately by the lifting table (27) and the intermediate tray (15), the first drive being designed as a single-axis drive that controls the position of the lifting table (27) controls in the stacking shaft (5), wherein the second drive is designed as a two-axis drive so that it controls the position of the clipboard (15) along a predetermined and repetitive path, and the third drive as Two-axis drive is designed so that it controls the position of the hold-down device (29) along a predetermined and repetitive path. Device according to claim 1, characterized in that the second drive and the third drive comprise two independent movement axes, a first movement axis (Y-axis) running orthogonally to the transport direction (T) and a second movement axis (X-axis) parallel to the Transport direction (T) runs. Device according to Claim 1 or 2, characterized in that the axes of movement of the drives are driven electrically, electro-mechanically, pneumatically or hydraulically. Device according to one of the preceding claims, characterized in that a transport device (7), in particular one or more parallel driven transport belts (9), is / are present below the stacking space (5). Device according to one of the preceding claims, characterized in that the first stop (1) is designed as a vibrating wall and / or that the second stop (3) is adjustable in the transport direction (T). A method for destacking a stream of folding box blanks (31) or folding box tubes in a stacking space (5) with the aid of a lifting table (27), an intermediate shelf (15) and a hold-down device (29), comprising the steps: - Retraction of the hold-down device (29) against the transport direction (T) into the stacking shaft (5) at a first height (Y ₁ ), - Step-by-step lowering of the hold-down device (29) in the stacking shaft (5) corresponding to a height () of the folding boxes (31) or folding box tubes placed on the holding-down device (29); - Moving the clipboard (15) into the stacking shaft (5) at a second height (Y ₂ ) below the hold-down device (29), whereby the step-by-step lowering of the hold-down device (29) and the moving of the clipboard (15) into the stacking shaft (5 ) at least partially in parallel / at the same time, - Lowering the hold-down device (29) in the stacking shaft (5) to a third height (Y ₃ ) so that the hold-down device (29) compresses a stack (33) of folding boxes or folding box tubes located below it on the lifting table (27), - Removal of the stack (33) of folding boxes or folding box tubes located on the lifting table (27) in the transport direction (T), and then - Lifting the lifting table (27) in the stacking shaft (5) to below the intermediate shelf (15) and - Moving the clipboard (15) out of the stacking shaft (5). Method according to Claim 6, characterized in that the intermediate depository (15) is moved into the stacking shaft (5) in the transport direction (T). Method according to Claim 6 or 7, characterized in that the intermediate depository (15) is moved out of the stacking shaft (5) counter to the transport direction (T).

Images