EP0541744B1

EP0541744B1 - Stacking process and device

Info

Publication number: EP0541744B1
Application number: EP19920910499
Authority: EP
Inventors: Martin Blümle
Original assignee: Winkler und Duennebier Maschinenfabrik und Eisengiesserei KG
Current assignee: Winkler und Duennebier Maschinenfabrik und Eisengiesserei KG
Priority date: 1991-05-28
Filing date: 1992-05-19
Publication date: 1995-09-06
Anticipated expiration: 2012-05-19
Also published as: FI925895A0; DE4117434A1; CA2087964C; FI925895A; WO1992021599A1; FI925895D0; DE59203570D1; FI106549B; ES2077416T3; CA2087964A1; FI106549B1; JPH06500300A; EP0541744A1; US5393196A

Abstract

The invention relates to a process and device for forming, maintaining, separating and transporting stacks, especially stacks (10, 11 or 10a, 11a) of envelopes (3) or the like, behind a delivery device (4, 4a) which lays continuously or individually arriving envelopes (3, 3a) on one of their edges (6, 6a) on a stacking surface (7, 7a). The essence of the invention consists in that: the items to be stacked (3, 3a) are first held at the start of the formation of the stack (10, 10a) by a first front stack support (8, 8a) moving in the direction of the increasingly large stack (10, 10a) (Fig. 4); a second front stack support (9, 9a) then takes the place of the first front stack support (8, 8a) (fig. 6); and after the completion of the stack (10, 11 or 10a, 11a; fig. 2) a third front stack support (12, 12a) and a rear stack support (13, 13a) take the stack (11, 11a) and transport it further; at the same time as the stack (11, 11a) is taken by the third front stack support (12, 12a) and the rear stack support (13, 13a), the first front stack support (8, 8a) together with the rear stack support (13, 13a) acts as a separator between the completed stack (11, 11a) and the parts (3, 3a) of the next stack (10, 10a) to be formed and supports it.

Description

The invention relates to a method and an apparatus for stacking, i.e. for forming, holding, separating and transporting stacks, in particular stacks consisting of envelopes or the like. Behind a depositing device which places individually arriving envelopes with one of their edges on a stacking surface.
A method and an apparatus of the type mentioned are known from CH-A-607 979. Thereafter, two stack supports are provided, namely a leading stack support which engages the front end of the stack in the transport direction and thereby holds the stacked parts secured in their vertical position against falling over, and a further stack support which corresponds to a length of a finished stack measured in the transport direction Distance behind the leading stack support is inserted from below into the stack being formed.
This further stack support is divided into a lower trailing support section and an upper leading support section. The trailing lower support section forms, together with the leading stack support, a transport unit that moves the finished stack in the transport direction at a higher speed than the stacking speed, while the leading support section only moves forward at the speed corresponding to the stacking process and thereby supports the newly formed subsequent stack.
After the finished stack has been released, the trailing support section is moved downwards and in the direction of the depositing device, while the advancing deposit support is moved back to the support position for the subsequent stack which is formed, whereupon the leading support section is also extended downward and in the direction of the depositing device is reset, in order to then be retracted together with the trailing lower support section at the appropriate point in the stack formed between two stack parts.
The known device works in principle satisfactorily, but can still be improved and made more efficient.
Accordingly, the object of the invention is to improve the aforementioned method and the corresponding device and to make it even more efficient.
This object is achieved with the features of claims 1 and 5, respectively.
Thereafter, the invention provides that during the removal of one stack and the simultaneous formation of the next stack, several stack supports are simultaneously active and are moved into the path of movement of the stack and out of its path of movement and along the path of movement.
In contrast to the prior art, not only are two stack supports serving as a transport unit, but there are also other stack supports that can also be moved. These further stack supports are, like the stack supports serving as a transport unit, movable stack supports into and out of the movement path of the stack and along the movement path of the stack, although the movement along the movement path is limited only to the area of stack formation. The stack supports, which can only be moved in the area of the stack formation, are also effective until their function is taken over by the other two stack supports, which also serve as a transport unit.
According to the exemplary embodiment, three stack supports are moved from one side transversely to the movement path and along the movement path of the stack and from a second side A fourth stack support is moved into and out of the movement path, and at times during the formation of the stack along the movement path. The movement of the three stack supports preferably takes place from bottom to top and back and in the longitudinal direction of the movement path, while the movement of the individual stack supports takes place from top to bottom and back and in the direction of the movement path of the stack.
Since the stack supports act partly simultaneously and partly alternately and complement one another, a continuous movement sequence is possible without interruption while the stacks are also continuously formed and the overall speed of the individual parts is low overall. This is associated with a high degree of operational safety and thus a low susceptibility to failure.
Further embodiments of the invention emerge from the subclaims in connection with the description and the drawing.
The invention is described below with reference to exemplary embodiments which are illustrated in the drawing. Show:

Fig. 1:: a schematic diagram of the device for stacking with a partially completed stack;
Fig. 2:: a schematic diagram as in Figure 1 with a completed stack and with the stack supports forming the transport unit in one position before they take over the stack.
Fig. 3:: a schematic diagram as in Figure 2 with the stack support forming the transport unit after they have taken over the stack.
Fig. 4:: a schematic diagram as in Figures 1 to 3 with a completed stack during removal and a further stack during new formation;
Fig. 5:: a schematic diagram as in Figures 1 to 4 with the completely transported, completed stack and the further stack when it is formed, it is still held by the first leading stack support;
Fig. 6:: a schematic diagram similar to that of FIG 5, but with the stack being formed being held by the second leading stack support;
Fig. 7:: a schematic diagram similar to that of FIG 6, wherein the stack being formed is held by the second leading stack support and the other stack supports are in a retracted waiting position from which they move to a standby position shown in FIG. 1.
Fig. 8:: a schematic side view of the storage and drive of the second leading stack support on a larger scale;
Fig. 9:: Details in an enlarged partial cross section from FIG. 8;
Fig. 10:: a basic plan view of the storage of the first leading stack support and the trailing stack support;
Fig. 11:: a schematic side view of the first leading stack support and the trailing stack support;
Fig. 12:: on a larger scale details of the storage of the first leading stack support;
Fig. 13:: a schematic diagram as in Fig. 5 of a modified embodiment and
Fig. 14:: 6 shows a schematic diagram as in FIG. 6 of the embodiment according to FIG. 13.

A device 1 for stacking, for example, envelopes 3 coming from a feed station 2 comprises, according to FIG. 5, a depositing device 4 with serrated lock washers 5. Feeding stations 2 and depositing devices 4 of the type of interest here are known in principle and are not the subject of the invention.
As FIG. 5 also shows, the continuously and individually arriving envelopes 3 are placed with one of their edges 6 by the depositing device 4 on a stacking surface 7 of the device 1 and are initially held there by a first leading stack support 8. The expression "leading" stack support means that this stack support is located in the front in the direction of stack formation - ie in the direction of arrow a in FIG. 5 - and a stack 10 or finished stack 11 is formed at its front end pointing in the direction α supports. As soon as the stack 10 has reached a predetermined size (FIG. 6), a second leading stack support 9 takes the place of the first leading stack support 8 and holds the forming stack 10, thereby the first leading stack support 8 out of the path of movement of the stack being formed 10 can be moved out. This is also shown in Fig. 6.
2, a third leading stack support 12 and a stack support 13 trailing in the transport direction take over the stack 11, the trailing stack support 13 engaging at the rear end of the stack. The two stack supports 12 and 13 together form a transport unit and transport the finished stack 11 out of the area of the stack formation point, for example to a turning and nesting station 14, as shown in FIGS. 2 to 5 and 6, respectively.
When the two stacking supports 12 and 13 serving as the transport unit take over the stack 11, the first leading stacking support 8 is simultaneously moved in front of the next part to be stacked. The first leading stack support 8 therefore also serves as a separating element between a completed, complete stack 11 and the next stack 10 that is being formed (FIGS. 2 and 3).
For forming, holding, separating and transporting stacks 10, 11, several, ie specifically four stack supports 8, 9 and 12, 13 are thus active and move both in the movement path of the stacks 10, 11 and out of their movement path and they move also along the movement path of the stacks 10, 11. Three stack supports 8, 12 and 13 move from one side transversely to the movement path of the stacks 10, 11 and along the movement path, while the fourth stack support 9 moves from a second side into the Movement path in and out of this and temporarily moved along the movement path during the stack formation.
According to the embodiment shown in Figures 1 to 7, the second leading stack support 9 is pivoted from above in front of the stack 10 being formed and moves during the stack formation along the path of movement of the stack 10 until it finally swings up again and then in the direction Storage device 4 moved back.
The individual figures show the different work steps as follows:
1, the second leading stack support 9 holds the stack 10 being formed, while the stack supports 12 and 13 serving as a transport unit, like the first leading stack support 8, are in a standby position. In this standby position, the stack supports 8 and 13 are located at a short distance in front of the stack 10 on its side facing the depositing device 4 and project with their free ends 16 somewhat over the stacking surface 7.
In Fig. 2 the stack 11 has reached its full size. The second leading stack support 9 and the third leading stack support 12 belonging to the transport unit are located in one plane. The trailing stack support 13 and the first leading stack support 8 located directly next to it have moved from the ready position according to FIG. 1 to the last part 15 of the complete stack 11. This takes place at a relatively low level, so that initially both the leading stack support 12 and the trailing stack support 13 abut the stack 11 only with their upper ends 16.
The two stack supports 12 and 13 according to FIG. 3 then move upwards on the stack and at the same time somewhat in the direction of movement of the stack 11 to be transported away.
The stack 10 or 11 expediently rests in the stack formation area on the upper run of a conveyor belt 17 which is guided around deflecting rollers 18 to 23 and around a driving deflecting roller 24. The transport speed of the two stack supports 12 and 13 forming the transport unit is greater than that of the conveyor belt 17, so that a gap 25 quickly arises to the next stack 10 which is being formed (FIG. 4). This next stack 10 which is being formed is held by the first leading stack support 8 which, together with the trailing stack support 13, has been moved from the ready position according to FIG. 1 to the last part 15 after completion of the stack 10 according to FIG. 2, this too was first carried out at a low level, whereupon the first leading stack support 8 is moved transversely to the stacking direction from the position according to FIG. 2 into the support position according to FIG. 3. Furthermore, the second leading stack support 9 moves out of the movement path of the stack 11 when the third leading stack support 12 has reached its upper position according to FIG. 3. At this stage, the stack support 9 pivots out of the path of movement of the stack 11 (FIG. 4).
5, the two transport supports 12 and 13 with the stack 11 have reached the turning and nesting station 14. The newly forming stack 10 has become somewhat larger during this time.
6 shows the situation in which the turning and nesting station 14 has taken over the stack 11 with its turning fork 26. Furthermore, a folding box 27 has already been pushed over the stack 11. The stack supports 12 and 13 serving as a transport unit can therefore be detached from the stack 11, for which purpose they are removed from the stack. According to the exemplary embodiment, this is done by lowering the two stack supports 12 and 13.
Before that, however, the second leading stack support 9, which can be swiveled in from above, has taken over the securing of the stack 10 being formed, as a comparison of FIGS. 5 and 6 shows. With the lowering of the two stack supports 12 and 13, the first leading stack support 8 was also lowered in accordance with the exemplary embodiment and is therefore no longer able to hold the stack 10 that is being formed (FIG. 6).
6, the three stack supports 8, 12 and 13 which can be moved from a common side transversely to the path of movement of the stacks 10, 11 then move into a waiting position on the right in FIG. 7. In this waiting position there are the free ends 16 of the stack supports 8, 12 and 13 still below the stacking surface 7 at a level at which they are moved back into the position according to FIG. 7 after the lowering according to FIG. 6. From this lowered level below the stacking surface 7, the stacking supports 8, 12 and 13 are then raised again to the ready position until their upper, free ends 16 are slightly above the level of the stacking surface 7, as is shown in FIG. 1. The steps described above are then repeated.
A device 30 is used for storing and driving the first leading stack support 8 and the stack supports 12 and 13 serving as a transport unit, which, with the aid of a lifting device 31 only shown in principle in the figures, moves from the raised position according to FIG. 1 into the position according to FIG. 6 can be lowered. The device 30 comprises means for storing and guiding and for driving the stack supports 8, 12 and 13.
Both the first leading stack support 8 and the two stack supports 12 and 13 forming a transport unit are each arranged on a carriage 32 or 33 and 34 (FIG. 1). For the storage and guiding of the slide 32 of the stack support 8, the device 30 according to the exemplary embodiment has external guide rods 35 and 36 (FIG. 10). For storing and guiding the other two stack supports 12 and 13, the device 30 comprises internal guide rods 37 and 38, only the slide 33 with the stack support 13 and not also the slide 34 with the stack support 12 being shown in FIG. 10. The pairs of guide rods 35 and 36 and 37 and 38 are also preferably at different heights, as can be seen in FIG. 11.
Both the trailing stack support 13 and the first leading stack support 8, which also serves as a separating element, each comprise, for example, four elongated, finger-like elements 39 and 40, which in turn are located on the guide rods 35 with the aid of angle irons 41 and 42 and at their ends to 38 mounted guide bushes 43 and 44 form the slides 32 and 33 according to Figures 10 and 11.
An electromagnetic clutch 45 is also fastened to the carriage 32 with the aid of a holder 46. This is shown in principle in FIGS. 10 and 12. Furthermore, the slide 33 of the trailing stack support 13 carries a steel plate 47 assigned to the electromagnetic clutch 45 (FIG. 12). The two slides 32 and 33 are therefore temporarily connected to one another by the holding force of the electromagnetic clutch 45.
What is essential is the connection of the two carriages 32 and 33 and thus the synchronous and common movement of the trailing stack support 13 and the first leading stack support 8 which also serves as a separating element when these stack supports 8 and 13 move from the ready position according to FIG. 1 into the separating position 2 are moved very quickly or almost suddenly, this must be done exactly between two parts to be stacked. After reaching the separation position according to FIG. 2, the two stack supports 8 and 13 still move together transversely to the movement path of the stack 11, but the two stack supports 8 and 13 are now separated from one another. The stack support 13 only has to hold the finished stack 11 when it is transported to the turning and nesting station 14, while the first front stack support 8 prevents the next parts deposited by the depositing device 4 from falling over.
The two carriages 32 and 33 are released in the area of their electromagnetic coupling 45 for separating the two stack supports 8 and 13 from one another with the aid of switches which are not shown in the figures and which can be controlled by the carriage itself.
The device 30 also includes a piston-cylinder unit 47, which can be, for example, a rodless cylinder, the piston of which, not shown in the figures, suddenly moves the two stack supports 8 and 13 from the waiting position according to FIG. 1 into the separating position according to FIG. 2. The free ends 16 of the two stack supports 8 and 13 are already in the waiting position according to FIG. 1 within the radius of the serrated lock washer 5 in the plane of the support 48 of the storage device 4, as also shown in FIG. 1. For this purpose, the device 30 is slightly raised by the lifting device 31.
The stack 11 is transported from the position according to FIG. 2 or FIG. 3 to the turning and nesting station 14 with the aid of the piston-cylinder unit 47, which for this purpose is connected to the trailing stack support 13 and moves it.
The piston-cylinder unit 47 also moves the trailing stack support 13 back into the starting position or waiting position according to FIG. 7, the carriage 32 of the first leading stack support 8 being coupled to the carriage 33 of the trailing stack support 13 with the aid of the electromagnetic clutch 45. The leading stack support 12 belonging to the transport unit receives its drive for the return movement from a return spring which is not shown in the figures for the sake of clarity.
Finally, a toothed belt 51 (FIGS. 10 and 11), which is driven synchronously with the conveyor belt 17 (FIG. 3), is also assigned to the slide 32 of the first leading stack support 8. This toothed belt 51 is coupled to or detached from the slide 32 via the clamping cylinder of a pneumatic coupling 52. This is necessary because the carriage 32 is temporarily coupled to the carriage 33 via the electromagnetic clutch 45 and is then moved by the latter.
The toothed belt 51 is guided with the aid of a deflection roller 53 at a free end 54 of the device 47 (FIG. 1) and also runs over deflection rollers 55 and 56 which are mounted on the piston-cylinder unit 47 or are height-adjustable together with the latter. Furthermore, the toothed belt 51 is guided over deflection rollers 57 and 58, which are mounted on a carrying and guiding device 59 (FIG. 1) for the device 30 with the piston-cylinder unit 47.
A guide and holding device 60 is provided for pivoting and for horizontally moving the second leading stack support 9, which can be swiveled in from above in front of the stack 10 that is being formed, the essential details of which can be seen in FIGS.
The stack support 9, like the stack support 12, comprises a plurality, preferably four elongated, finger-like elements 61 which are arranged on a carrier 62 and, together with the latter, can be pivoted about an axis 65 on arms 63 of a carriage 64 are stored. The carriage 64 is slidable along guide rods 66 which are part of the guiding and holding device 60.
A toothed belt 69, which is guided around a drive wheel 67 and a deflection wheel 68 and which can be coupled to or detached from the slide 64, is provided as the drive for the slide 64. For this purpose, a pneumatic coupling 70 is again provided, which is only indicated schematically on the carriage 64 in FIG. 8. The toothed belt 69 is basically driven synchronously with the conveyor belt 17, so that it is necessary to detach it from the toothed belt 69 when the stack support 9 or the carriage 64 carrying it are moved back into the starting position according to FIGS. 4 and 5.
A roller spring 71 is used to retract the carriage 64, which is attached at one end 72 in the area of the drive wheel 67 to the guiding and holding device 60 and is also guided around a roller spring drum 73 which is mounted on the carriage 64.
A pivot cylinder 74 is used to pivot the stack support 9, the piston rod 75 of which is articulated on an arm 76 of the carrier 62. Another arm 77 serves as a carrier for the swivel cylinder 74 and connects it to the carriage 64.
Finally, the guide and holding device 60 also includes an upper stack guide element 80 (FIGS. 1, 8) which is carried by vertically adjustable guide rods 81 and through which the finger-like elements 61 of the stack support 9 extend.
FIGS. 13 and 14 show a modified device 1a for stacking or for forming, holding, separating and transporting stacks 10a and 11a, however, the same reference numbers with the index a serve for the same parts.
The device 1a according to FIGS. 13 and 14 differs from the device 1 described first only in that the second stacking support 9a on a carriage 64a cannot be pivoted but can be moved perpendicular to the stacking surface 7a. The second leading stack support 9a is mounted such that it can move in the vertical direction and can also be moved parallel to the stack 10a which is becoming larger by means of the slide 64a.
The storage and the drive for the slide 64a in the guiding and holding device 60a can basically be designed in the same way as in the exemplary embodiment described first. A difference therefore only exists in that the carriage 64a carries a lifting device 90a, for example in the form of a piston-cylinder device, with the aid of which the second leading stack support 9a is raised as required, as shown in FIG. 13, or is lowered, as is the case with this is shown in Fig. 14. For this purpose, the carriage 64a has an upwardly extending carrier 91a, to the upper end of which the piston-cylinder device 90a is fastened. A driver 93a connects the free end of the piston rod 92a to the second leading stack support 9a, which is also preferably guided and supported in the slide 64a.
The function and mode of operation of the guiding and holding device 60a with the second leading stack support 9a, which can be moved parallel and vertically to the stacking surface 7a, when interacting with the first leading stack support 8a and the two other stack supports 12a and 13a do not differ from the exemplary embodiment described first. As long as the stack support 8a according to FIG. 13 holds the stack 10a, the stack support 9a is in a raised position. If the two stack supports 12a and 13a release the stack 11a and are lowered for this purpose, the stack support 8a also releases the newly formed stack 10a, since it is lowered together with the other two stack supports 12a and 13a. At the same time, the stack support 9a takes over the holding function on the stack 10a, for which purpose it is pushed in front of the stack 10a by the lifting device 90a, as is shown in FIG. 14.
The three stacking supports 8, 12 and 13 or 8a, 12a and 13a move together in the vertical direction or perpendicular to the stacking surface 7 or 7a and in the horizontal direction only partially when the two stacking supports 8 and 13 or 8a and 13a from the waiting position according to FIG. 7 move into the ready position according to FIG. 1 and then via the separation position according to FIG. 2 into the transport and takeover position according to FIG. 3. In the subsequent movement processes until the waiting position is reached, the stack supports 8, 12 and 13 or 8a, 12a and 13a move largely independently of one another.

Claims

A process for forming, holding, separating and transporting stacks, in particular stacks (10, 11 and 10a, 11a respectively) consisting of envelopes (3) or the like, downstream of a delivery device (4, 4a) which deposits continuously and individually arriving envelopes (3, 3a) with one of their edges (6, 6a) on a stacking surface (7, 7a), characterised in that
- the items (3, 3a) to be stacked, at the beginning of the formation of the stack (10, 10a), are initially held by a first leading stack support (8, 8a) which moves in the direction of the stack (10, 10a) as it increases in size (Figure 4),

- then a second leading stack support (9, 9a) takes the place of the first leading stack support (8, 8a) (Figure 6), and

- after the stack (10, 11 and 10a, 11a; Figure 2) is finished a third leading stack support (12, 12a) and a trailing stack support (13, 13a) take over the stack (11, 11a) and transport it away,

- wherein simultaneously with the stack (11, 11a) being taken over by the third leading stack support (12, 12a) and the trailing stack support (13, 13a) the first leading stack support (8, 8a) also passes together with the trailing stack support (13, 13a) as a separating element between the finished stack (11, 11a) and the items (3, 3a) of the next stack (10, 10a) to be formed and supports it.
A process according to claim 1 or claim 2 characterised in that three stack supports (8, 12, 13 and 8a, 12a, 13a respectively) are moved from one side transversely to the path of movement of the stack (10, 11 and 10a, 11a) and along the path of movement of the stacks (10, 11 and 10a, 11a) and that the fourth stack support (9, 9a) is moved into the path of movement fro a second side and out of the path of movement and during stack formation is moved at times along the path of movement and then back again.
A process according to claim 1 or claim 2 characterised in that two leading stack supports (8, 12 and 8a, 12a) and the trailing stack support (13, 13a) are moved from the same side and the further leading stack support (9, 9a) is moved from another side into the path of movement of the stack (10, 11 and 10a, 11a) and out of same.
A process according to one of claims 1 to 3 characterised in that the third leading stack support (12, 12a) and the trailing stack support (13, 13a) form a transport unit and that the two further leading stack supports (8, 9 and 8a, 9a) successively support the stack (10, 10a) being formed until after the full stack size is reached the stack supports (12, 13 and 12a, 13a) serving as a transport unit take over the stack (11, 11a).
Apparatus for forming, holding, separating and transporting stacks, in particular stacks (10, 11 and 10a, 11a respectively) consisting of envelopes (3, 3a) or the like, downstream of a delivery device (4, 4a) which deposits continuously and individually arriving envelopes (3, 3a) with one of their edges (6, 6a) on a stacking surface (7, 7a), wherein there are also provided movable stack supports and drive moans for the stack supports, characterised in that there are provided three leading stack supports which are movable into the path of movement and out of the path of movement of the stacks (10, 11 and 10a, 11a) and along the path of movement of the stacks (10, 11 and 10a, 11a) and a trailing stack support (13, 13a) which is movable into and out of the path of movement and along the path of movement of the finished stack (11, 11a).
Apparatus according to claim 5 characterised in that two leading stack supports (8, 12 and 8a, 12a) are movable from the same side as the trailing stack support (13, 13a) and the further leading stack support (9, 9a) is movable from another side, into the path of movement of the stack (10, 11 and 10a, 11a) and out of same.
Apparatus according to claim 5 or claim 6 characterised in that three stack supports (8, 12 and 13, 8a, 12a and 13a) are mounted beneath the stacking surface (7, 7a) and a stack support (9, 9a) is mounted above the stack (10, 11 and 10a, 11a).
Apparatus according to claim 7 characterised in that the stack support (9) which is mounted above the stack (10, 11) is pivotable and is mounted displaceably in the direction of movement of the stack (10) being formed.
Apparatus according to claim 7 or claim 8 characterised in that the stack supports (8, 12 and 13, 8a, 12a and 13a) which are mounted beneath the stacking surface (7, 7a) are arranged on sliders (32, 33, 34) movable in the direction of movement of the stack (10, 11 and 10a, 11a), and are movable jointly by means of a lift device (31) transversely to the direction of movement of the stack (10, 11 and 10a, 11a).
Apparatus according to one of claims 5 to 9 characterised in that the one leading stack support (9, 9a) can be pivoted from above into a position in front of the stack (10, 10a) being formed and relative to the one leading stack support (8, 8a) which is movable from below into a position in front of the stack (10, 10a) and during stack formation is movable along the path of movement of the stack (10, 10a) and finally can be pivoted away upwardly again and is then movable in the direction of the delivery device (4, 4a).
Apparatus according to one of claims 5 to 10 characterised in that the second leading stack support (9a) is movable parallel and vertically relative to the stacking surface (7a).