EP1084977B1 - Method for transporting sheets and device for carrying out this method - Google Patents

Description

The invention relates to a method for transporting leaves according to the preamble of claim 1 and an apparatus for Implementation of such a method according to the preamble of Claim 4.

In a known device, the leaves are from a feeder supplied from. In it, the leaves are stacked, by rollers be detected and read one after the other. About the transport elements the leaves are transported to the stop unit, on they are held until they are fed from the stack Leaves are summarized sentence by sentence. Once this stack of leaves is generated, the stop unit is turned on, causing this Sheet set is fed to a subsequent station. With the power on this stop unit also turns on the feeder, so that the leaves of the next sentence to be formed to the stop unit be transported. Once the previously formed stack wegtransportiert has been off, the stop unit is turned off, so that the subsequent leaves on the stop unit to a new Pile can be formed. In this way, one after another formed the corresponding sets of sheets on the stop unit and transported intermittently. The leaf sets are having considerable Time intervals formed successively on the stop unit and transported by her. With this approach and this Device can therefore be achieved no high performance.

In the generic method and the generic device (DE 44 41 453 A) is the first sheet of a newly formed Stack is then fed into the stacking station when the on the stop unit applied finished stack transported from the stacking station has been. Only then is the first sheet of the new to forming stack transported until it stops at the stop unit is applied. Even with such a method, the sheet sets with considerable time intervals formed successively on the stop unit. High machine performances are with this procedure and this device not possible.

Also in other known methods and devices (US-A-5 373 825; US-A-5 364 085) will be the first sheet of a new one Stacks transported to the stacking station only when the on the stop unit fitting finished stack completely from the Stacking station has been removed.

The invention is based on the object, the generic method and the generic device in such a way that high Achievements without the safety in the feeder affecting the leaves.

This object is according to the invention in the generic method with the characterizing features of claim 1 and at the generic device according to the invention with the characterizing Characteristics of claim 4 solved.

In the method according to the invention, the on continues the stop unit formed stack and the feeding of the sheet of the next stack to be formed overlapping. In the Stacking is not first waited until the finished stack of the Stop unit is further promoted before the first sheet of is supplied to next stack to be formed. The onward transport of the stack formed on the stop unit takes place as soon as the first sheet of the next stack to be formed on the stop unit overlapping stack overlaps. That way very high cycle times and thus a very high performance. The Device according to the invention has the sensor device which in the Promotion of a belonging to a new stack to be formed Sheet provides a signal to turn on to the stop unit, if this sheet finished fitting the stop unit Stack overlaps. As a result of the inventive training has the Device according to the invention a high performance.

In the simplest case, each stack consists of only one sheet. Of course, the stack may also consist of two or more sheets consist.

Further features of the invention will become apparent from the further claims, the description and the drawings.

Fig. 1

in schematischer Darstellung den Verfahrensablauf bei Einsatz einer erfindungsgemäßen Vorrichtung,

Fig. 2

in Seitenansicht eine erfindungsgemäße Vorrichtung,

Fig. 3

in Draufsicht die Vorrichtung gemäß Fig. 2, wobei der Übersichtlichkeit wegen übereinander liegende Teile nebeneinander gezeichnet dargestellt sind.

The invention will be explained in more detail with reference to an embodiment shown in the drawings. Show it

Fig. 1

a schematic representation of the procedure when using a device according to the invention,

Fig. 2

in side view a device according to the invention,

Fig. 3

in plan view, the device of FIG. 2, wherein the sake of clarity because of superposed parts are shown side by side drawn.

The device serves to set individually supplied documents sentences to collect the sets and then post-processing. In Fig. 1, the process flow is shown schematically. The device 1 is an accumulator which is on its input side has two superimposed waves 2, over each Transport belt 3 are guided. With them, documents, such as Leaves, transported by the accumulator 1. On the output side is the accumulator 1 provided with superposed waves 4, over which the conveyor belt 3 are guided. In the area between the Shafts 2 and 4 is a stop unit 5, which in the embodiment arranged one above the other, driven in opposite directions Rolls exists. Advantageously, this stop unit 5 in Direction of transport of the leaves adjustable, so that the accumulator on different sheet sizes can be adjusted.

In the conveying direction behind the waves 2 is a ramp 6, the ensures that the coming of a feed system 7 sheet is raised becomes. The leaves run on the sloping side of the ramp 6 and are thereby raised in this area. Such ramps 6 are known in such accumulators 1 and are therefore also not explained in detail. The delivery system 7 is at least associated with a reading system 8, with which the individual sheets before the supply to the accumulator 1 can be read. The reading system 8 is in the illustrated embodiment in the area between the delivery system 7 and the accumulator 1. The reading system 8 detects the individual leaves and ensures that to a Set belonging sheets to be put together. In the simplest Case, such a sentence consists of only one sheet. It is also possible to combine two or more leaves in one sentence. The delivery system 7 may be, for example, a feeder.

At the beginning of Akkumuliervorganges a first sheet 9 on the Transport belt 3 supplied from the feed system 7 until it with his front in the transport direction edge on the stop unit. 5 comes to the plant. The roles of the stop unit 5 stand still, so that this sheet 9 remains in its investment position until the subsequent sheet 10 is supplied. In Fig. 1 the case is shown, that each sentence consists of only one sheet. In Fig. 1 are the three positions in the passage of the sheet 9 through the accumulator 1 shown. In the middle position, the sheet 9 is with his front in the transport direction edge on the stop unit. 5 on. The following sheet 10, which in the embodiment to a belongs to other sentence is from the feed system 7 via the conveyor belt transported in the accumulator 1. About the ramp 6 is the front edge of the sheet 10 raised in the direction of transport so far, that it is applied to the stop unit 5 sheet 9th overlaps. Once the overlap has occurred, the Rolls of the stopper unit 5 driven so that the sheet 9 in Direction is transported to a post-processing unit 12. Preferably, the succeeding sheet 10 becomes the same speed as the sheet 9 transports. As soon as this succeeding Sheet 10 with its front in the transport direction edge on the Stop unit 5 comes to rest their roles are stopped. This ensures that the first sheet 9 over part of his Length transported in the direction of the post-processing unit 12 is and the subsequent sheet 10 is in the stop position (lower illustration in Fig. 1). Now it is described in the Way supplied from the feed system 7, the next sheet 11. It is again read by the reading system 8 and the accumulator 1 supplied. Its front edge returns to the ramp 6, so that the sheet 10 is raised at this edge. As soon as that Sheet 11 overlaps the sheet 10, the drive of the rollers is again the stop unit 5. This has the consequence that the sheet 9, the still between the rollers of the stop unit 5, is completely transported out of the accumulator 1, while the sheet 10 is transported so far until the sheet 11 to the plant the roles of the stop unit 5 passes. She will turn then off. In this way, the individual will successively Sheets fed through the accumulator 1.

Due to the procedure described, the feed system 7 can not be turned off, but can be operated continuously become. This results in extremely short throughput times of Leaves 9 to 11 through the accumulator 1, due to this procedure has a high performance.

For an optimal lead time of leaves 9 to 11 through the accumulator 1, these are after their attachment to the stop unit 5 further transported over half their length.

Turning off the stop unit 5 takes place when the in Transport direction front edge of the respective sheet 9 to 11 a light barrier 13 passes, which advantageously at the post-processing unit 12 is provided. Once the respective sheet 9 to 11 with its front edge reaches the light barrier 13, this gives a shutdown signal to the stop unit 5, whereby their roles being stopped.

In the same way, the rollers of the stop unit 5 are switched on, when coming from the feed system 7 leaves 9 to 11 get on the ramp 6 and located in the stop position Overlap sheet by a certain amount. The accumulator 1 is provided for this purpose with a light barrier 14, which in the embodiment in the direction of transport of the leaves immediately behind the Ramp 6 is located. As soon as each subsequent sheet 10, 11 the each front sheet 9, 10 overlaps, sends the light barrier 14 a corresponding signal to the stop unit 5, thereby turned on becomes.

The post-processing unit 12 is at the entrance end with a transport device 15 provided, for example, by superimposed Rolls or rollers is formed. This transport device 15 can be continuously driven as the respective Leaves 9 to 11 due to the light barrier 13 just before the transport device 15 are stopped.

The position of the stop unit 5 relative to the light barrier 13 or to the waves 4 is before the accumulation on the format the leaves to be transported 9 to 11 set. If that Paper size changes, the stop unit 5 in the direction of Double arrow 16 in Fig. 1 so adjusted that the leaves between the Ramp 6 and the stop unit 5 come to rest. Of the Distance 17 between the axes of the rollers of the stop unit and the ramp 6 corresponds to the length of the sheet 9 to be transported to 11. The ramps 6 are accordingly in the transport direction the leaves 9 to 11 adjusted. Is in the illustrated embodiment for example, uses a shorter sheet size, must the distance between the stop unit 5 and the output side Shafts 4 of the accumulator 1 are reduced in size. Accordingly but must also the ramp 6 in the direction of the waves. 4 be adjusted horizontally. On the other hand, become longer sheet sizes used, the stopper unit 5 and the ramp 6 in the other Direction adjusted.

The accumulator 1 works fully automatically. The reading system 8, the Rolls of the stop unit 5, the waves 2, 4 and the associated Photocells 13 and 14 are integrated in the control. she has at least one microcontroller, in the feed system 7, in the accumulator 1 or be provided in the post-processing unit 12 can.

The delivery system 7 may have any suitable design. Also the Postprocessing unit 12 may be any suitable device For example, a folding machine, a packaging machine, the Part of an inserter, a stapler, a welding device and the same. The through the accumulator. 1 transported leaves 9 to 11 can thus on the most diverse Be processed.

In FIG. 1, for the sake of clarity, it has been assumed that each set consists of only one sheet 9, 10 or 11 respectively. In sentences, which consist of several leaves, each equal or can also be different, the individual leaves become the stopper unit 5 stacked to the respective sentence. So long will be the stop unit 5 is not turned on. Only when the respective Set has been formed on the stop unit 5 and the first sheet of the next sentence overlaps the stacked sentence is described in the Way the stop unit 5 is turned on. To this One way at a time are the respective sets on the stop unit 5 formed and then the individual sentences in the described Way the post-processing unit 12 supplied. The reading system 8 Detects when a sheet of the next batch is fed and gives a signal to the stop unit. 5

With reference to FIGS. 2 and 3, the accumulator 1 will be explained in more detail. He has a frame 18 in which a motor 19 is housed. His drive shaft 20 is over a Endlostrieb 21 with an intermediate shaft 22 drivingly connected, in side walls 23, 24 (Fig. 3) of the frame 18 is rotatably mounted. As shown in FIG. 3, sits on the over the sidewall 23 projecting end of the intermediate shaft 22 a pulley 25, over which the endless drive 21 (FIG. 2) is guided. The over the side wall 24 of the frame 18 projecting end of the intermediate shaft 22 carries a pulley 26 through which an endless belt 27 is guided. It connects the intermediate shaft 22 with a shaft 28 and the shafts 2. The ends of the shafts 2, 28 are in the side walls 23, 24 of the frame 18 rotatably mounted. The necessary Tension of the endless belt 27 is by two tension rollers 29, 30th achieved, which is rotatably mounted on the outside of the side wall 24 are. In FIG. 3, only one tension roller 30 is the clear view shown, which is located adjacent to the upper shaft 2. The Tension pulley 29 is, as shown in FIG. 2, immediately adjacent to the Waves 2, 28.

As is apparent from Fig. 2, the upper shaft 2 with respect to the lower Shaft 2 offset in the transport direction of the leaves 9 to 11 forward arranged. But this offset is only so great that, in plan view seen on the accumulator 1, the two shafts 2 each other overlap.

On the two shafts 2 sitting non-rotatably pulleys 31, 32, over which the endless conveyor belts 3 are guided. The pulleys 31, 32 are axially spaced from each other. The lower legs the upper transport belt 3 and the upper run of the lower Transport belts 3 are arranged so that they, in the axial direction of the Waves 2, 4, touch each other, possibly slightly overlap each other. This ensures that even thin Leaves perfectly between the conveyor belt 3 inside the Accumulator 1 can be transported. The axial distances of the Pulleys 31, 32 on the shafts 2 are so large that different Sheet formats properly transported through the accumulator can be. The transport belt 3 are advantageous made of elastic material and are designed as round belts. The to drive provided Endlostriebe 21, 27, however, have band-shaped belts.

The upper conveyor belts 3 connect the upper shaft 2 with the upper shaft 4 provided with respective pulleys 33 is. Accordingly, the lower conveyor belt 3 connect the lower shaft 2 with the lower shaft 4, also on the corresponding Pulleys 34 sit.

The axes of the two shafts 4 are in contrast to the axes the waves 2 in a common vertical plane. The two ends the shafts 4 are mounted in the side walls 23, 24 of the frame 18.

The ramp 6 extends between the two side walls 23, 24 and is adjustable in the transport direction of the leaves 9 to 11. The Side walls 23, 24 of the frame 18 are in the transport direction lying slots through which the front side of the ramp 6 provided axes 35, 36 protrude. As shown in Fig. 2, the ramp has 6 at least one, preferably at both ends parallel to Side wall 23 and 24 of the frame 18 lying tabs 37 at each one end of an endless circulating chain 38 attacks. The chains 38 are over in side view (Figure 2) between the strands the lower conveyor belt on horizontal axes 39 rotatably seated Sprockets 40 deflected to sprockets 41, the rotation on a horizontal shaft 42 sitting in the area below the Transport belt 3 is located and the two ends in the frame side walls 23, 24 are rotatably mounted. The axes 39 are in attached to the side walls 23, 24 of the frame 18. The sprockets 40, 41 lie on the opposite outer sides of the Frame side walls 23, 24. Of the sprockets 41 are the chains 38 deflected to further sprockets 43, which on one between the two strands of the lower conveyor belt 3 lying shaft 44th sit. Their two ends are in the frame side walls 23, 24th stored. The shaft ends protrude in the transport direction of the Leaves 9 to 11 extending slots 45 in the frame side walls 23, 24. In the respective position, the shaft 44 is suitable Way relative to the frame side walls 23, 24 secured in position. By appropriate displacement of the shaft 44 in the slots 45th lets the tension of the chains 38 set to the desired extent. The chains 38 are at their other end to the tabs 37th the ramp 6 attached. As shown in Fig. 3, this is one end of the shaft 42 extended beyond the frame side wall 24 and carries a Handle 46, preferably a rotary wheel with which the shaft 42 to its axis can be turned. In the respective rotational position is the Shaft 42 clamped by a clamping device 47, the frame side is provided. The clamping device 47 has a on the frame 18 provided sleeve 48 through which the shaft 42 projects. In the Socket 48 is screwed radially a clamping bolt 49, with which the Shaft 42 in the socket 48 and thus relative to the frame 18th can be clamped rotationally fixed.

To move the ramp 6, it is possible to face each other Inner sides of the frame side walls 23, 24 rail-like To mount strips on which end sleds of the ramp 6 be guided horizontally.

The stop unit 5 can in the transport direction of the leaves. 9 to 11 are adjusted to the accumulator 1 to different To set paper sizes. The stop unit 5 has two superimposed waves 50, 51, which are at the same height as the adjacent waves 4 lie and between the strands of the upper and the lower conveyor belt 3 run. The two waves 50, 51 are at their near the frame side wall 23 lying end via a respective gear 52, 53 with each other. That on the Shaft 50 seated gear 52 also meshes with a gear 54, which is rotatably mounted in a support plate 55, through which which extend one end of the shafts 50, 51 and in which they are rotatable are stored.

At the other, adjacent to the frame side wall 24 lying end the shaft 50 is rotatably supported by a bearing 56 in a support plate 57. The lower shaft 51 extends through this support plate 57 and carries at its protruding end a pulley 58, the via a drive belt (not shown) with one on one Motor shaft 59 seated pulley 60 is drivingly connected. The motor 61 for driving the shafts 50, 51 of the stop unit 5 is attached to the support plate 57, which is as well as the opposite Support plate 55 extends in a vertical plane. As Fig. 2 shows, the support plate 57 extends down over the conveyor belt 3. The motor 61 is in the area below the conveyor belt 3 on the support plate 57 facing away from the frame side wall 24 thereof Side attached. At the bottom are the opposite ones Support plates 55, 57 by an axis 62 with each other connected, which passes through the support plates 55, 57 with their ends and in horizontal slots 63 in the rack sidewalls 23, 24 protrudes. The two support plates 55, 57 are also opposite Edge area supported on the frame side.

The upper shaft 50 is spring loaded in the direction of the lower shaft 51, so that they are limited relative to the shaft 51 radially displaced can be. This is necessary if the transported Sheet stack has a greater thickness. To this displaceability too ensure the passages 64 are in the support plates 55, 57 further than the shaft 50. The shaft 50 is in the region of its ends received in a sleeve through the passages 64 sticks out. At a radial approach of these sockets engages each one End of a tension spring 65, the other end to the support plate 55th or 57 is attached.

The support plates 55, 57 are at the bottom with one opposite Transport direction 16 extending neck 66, 67 provided through which the ends of the axle 62 protrude. The lugs 66, 67 are tab-shaped (Fig. 2) and are in the range between the two frame side walls 23, 24. At the free end of the Approach 67 is a tab 68 attached to the two ends a circumferential chain 69 are attached (Fig. 2). She is over two Sprockets 70, 71 guided on a shaft 72 and the shaft 42. While the sprockets 41 are located outside the frame 18 (FIG. 3), are the sprockets 71 within the frame 18. The two Sprockets 70, 71 have the same diameter, which is smaller as the diameter of the sprockets 41 on the shaft 42, over the the chains 38 are guided for adjusting the ramp 6. The diameters the sprockets 41 and 71 on the shaft 42 are chosen to that when turning the shaft 42, the ramp 6 by twice the way is adjusted in comparison to the stop unit 5. In this way Be the stopper unit 5 and the ramp 6 in an adjustment adjusted to the desired paper size at the same time. To the Turning the shaft 42 only has the clamping bolt 49 screwed back so far be that the shaft 42 in the sleeve 48 freely rotatable is. With the handle 46, the shaft 42 can then in the desired Dimensions are twisted, using the described chain drives the stopper unit 5 and the ramp 6 at the same time in the same Direction be adjusted. Subsequently, the clamping bolt 49 tightened again and thereby clamped the shaft 42 in the socket 48.

On the two shafts 50, 51 of the stop unit 5 sit rotationally fixed Rollers 73, 74, the axial distance from each other and the circumference are advantageously provided with friction linings 75, 76. Lie with them the rollers 73, 74 under the force of the tension springs 65 to each other. The rollers 73, 74 are, seen in plan view of FIG. 3, in the area arranged between the conveyor belt 3.

When adjusting the stop unit 5, the axis 62 with their both ends in the transport direction 16 extending Slits 63 moved. The support plates 55, 57 are also guided on the opposite edge in a suitable manner on the frame side. The ramp 6 is in the manner described on the frame side walls 23, 24 when moving out, so that a problem-free Adjustment of these units of the accumulator 1 guaranteed is.

The light barrier 14 in the region of the ramp 6 triggers in the described Set the time for the two shafts 50, 51 of the stop unit 5 off. As soon as the respective subsequent sheet 10, 11 the photocell 14 happens, the motor 61 receives a corresponding switch-on signal, so that the shafts 50, 51 are rotated and their rollers 73, 74 the voltage applied to the stop unit 5 sheet 9 and the sheet set transport to post-processing unit 12. The light barrier 13 in the transport direction behind the shafts 4 serves as additional security, because with her the sentence separation can be checked. To this It is ensured that the individual sentences, which consist of only one but also consist of several leaves, controlled and exactly separated from each other fed to the post-processing unit 12 become.

Claims (16)

1. A method for transporting sheets (10, 11), which are each conveyed one after another as far as a stop unit (5) and are stopped there until a stack composed of at least one sheet is formed, which stack is then transported onward by means of the stop unit (5),
   characterised in that the onward transport of the stack (9) takes place as soon as a sheet (10, 11) of the respective next stack to be formed overlaps the stack (9) abutting the stop unit (5), wherein the stack abutting the stop unit (5) and the following sheet (10, 11) of the next stack to be formed are transported simultaneously from the overlapping onwards.
2. A method according to Claim 1,
   characterised in that, during its transport to the stop unit (5), each sheet (9 to 11) is conveyed over at least one ramp (6) arranged in front of the stop unit (5) preferably at a distance (17) corresponding to the length of the sheet (9 to 11).
3. A method according to Claim 1,
   characterised in that the sheets (9 to 11) are supplied by a preferably continuously operated supply system (7).
4. A device for implementing the method according to one of Claims 1 to 3, comprising transport elements (3), preferably transport belts, for the sheets (9 to 11) and comprising a stop unit (5) which lies in the transport path of the sheets (9 to 11), is operable cyclically and is connected to a control, to which, for its part, a sensor arrangement (14) is connected, which during the conveying of a sheet (10, 11) belonging to a stack to be newly formed delivers an activating signal to the stop unit (5) when the sheet (10, 11) overlaps the stack (9) abutting the stop unit (5),
   characterised in that the stack (9) abutting the stop unit (5) and the following sheet (10, 11) are transported simultaneously from the overlapping onwards.
5. A device according to Claim 4,
   characterised in that at least one ramp (6) is provided in the transport path (16) of the sheets (9 to 11) in front of the stop unit (5), which lifts the sheet (9 to 11) for a short time out of its transport plane during its transport and preferably has a spacing (17) from the stop unit (5) corresponding to the sheet length in the transport direction (16).
6. A device according to Claim 5,
   characterised in that the respectively following sheet (10, 11) may be lifted by means of the ramp (6) such that it passes over the respective stack (9) located ahead of it.
7. A device according to Claim 5 or 6,
   characterised in that the ramp (6) and/or the stop unit (5) are adjustable in the transport direction (16) of the sheets (9 to 11) preferably via a common adjustment drive (42, 38, 69).
8. A device according to Claim 7,
   characterised in that the adjustment drive (42, 38, 69) has two continuous drive mechanisms (38, 69) preferably guided via a common drive shaft (42).
9. A device according to Claim 7 or 8,
   characterised in that the adjustment path of the stop unit (5) and ramp (6) is provided in the ratio of 1 : 2.
10. A device according to one of Claims 4 to 9,
    characterised in that the stop unit (5) has mutually parallel shafts (50, 51), on which mutually adjoining rollers (73, 74), which touch one another, are seated advantageously under force, preferably spring force.
11. A device according to Claim 10,
    characterised in that the rollers (73) of one shaft (50) are movable radially in a limited manner in relation to the rollers (74) of the other shaft (51).
12. A device according to Claim 11,
    characterised in that one shaft (50) with the rollers (73) is movable radially in a limited manner in relation to the other shaft (51).
13. A device according to one of Claims 4 to 12,
    characterised in that at least one supply system (7), which is operable continuously, is connected ahead of the device (1).
14. A device according to one of Claims 4 to 13,
    characterised in that at least one sensor arrangement (13) for checking the batch separation is provided behind the stop unit (5), in the transport direction (16) of the sheets (9 to 11).
15. A device according to Claim 13 or 14,
    characterised in that at least one reading system (8) is provided in the region between the supply system (7) and the device (1) connected thereafter.
16. A device according to one of Claims 4 to 15,
    characterised in that at least one microcontroller advantageously housed in the supply system (7), in the device (1) or in a following device (24) is provided for controlling the device (1).

Images