GB2111027A - A document assembler - Google Patents

Abstract

A document assembler comprises a support station (2), a stacker (1) to receive a stream of sheets and to deposit them one above the other in a stack at the support station (2), and a carrier (3) to move an assembled document away from the support station (2). The support station (2) includes two sets of blades (6) arranged to support opposite sides of the sheets with each set including at least two blades (39) and a rotary drive (13) for counter rotating the sets of blades (6) to lower and dump the assembled documents supported by the blades (6) between the sets of blades and onto the carrier (3). Rotation of the sets of blades (6) also moves the next blades of the two sets into position to receive the following sheets from the stacker (1) to form the next document. The paddle blades (39) are preferably arranged in a cruciform, so that registration of the stack is also achieved. <IMAGE>

Description

SPECIFICATION A document assembler This invention relates to a document assembler for assembling a number of individual sheets of paper or card to form a document. The sheets may all be identical or may be different such as individual cheques being assembled to form a cheque book.

Other sheets to be assembled into documents may be bank notes, lottery tickets, bank credits, travellers' cheques or transaction coupons.

The documents may then be stitched and bound to form a book, or alternatively the assembled document may subsequently be fed into an envelope or wrapped into a bundle.

Cheques and other similar papers are typically printed with non-variable or variable personalised information by a machine such as that partly described in British Patent Specification No 1 214639.

The output of such a machine is a stream of successive sheets which are fed at a high speed, typicaily eight per second. Documents assembled from such a stream may contain just two or three sheets or may contain 50 sheets or more.

The document assembler for assembling a document from such a stream of sheets must be capable of receiving this stream of sheets, assembling them into separate documents and moving the assembled documents to a downstream document handling stage.

A known document assembler for assembling sheets of cheques to form cheque books includes a slotted rotating wheel, the stream of sheets being fed to the slotted wheel with the slots in the wheel receiving the leading edge of the sheets. The rotation of the slotted wheel turns the sheets over and drops them one above the other in a stack. The trailing edge of the sheets in the stack rest on a sliding carrier, and the leading edge is supported above the sliding carrier by paddles of two paddle wheels mounted on a common shaft arranged beneath the slotted wheel. The paddle wheels each include four paddles.As soon as the required number of sheets have been assembled, the paddle wheels are rotated moving the paddles supporting the stack downwards, thus dropping the leading edges of the sheets of the assembled document into the sliding carrier, and bringing the next paddle of the wheels into a sheet supporting position. At the same time, a separator arm moves forwards from under the slotted wheel and between the paddle wheels and this separator arm supports the trailing edges of the sheets to form the next document above the sliding carrier whilst the preceding document is being moved away on the carrier to a transfer station.The sliding carrier then returns and the separator arm moves backwards beneath the slotted wheel, dropping the trailing edge of the sheets onto the sliding carrier, the leading edges of the sheets being held over the sliding carrier by the next paddles of the paddle wheels. As soon as the next document has been assembled, the cycle is repeated.

Disadvantages of this document assembler are that four separate timed mechanical actions are required which result in the assembler having to include a complex mechanical drive mechanism.

The separator arm, if slightly mistimed, can knock documents or individual sheets off the paddle wheels which causes the machine to jam or the documents to be mixed up. Due to its mechanical complexity, the known document assembler is expensive to manufacture. Furthermore, this assembler is not capable of operating at speeds required to assemble a small number of sheets, such as two to three sheets, by virtue of its mechanical construction. In practice, the machine would have to be slowed or the continuous printing process would need to be interrupted.

According to this invention a document assembler for assembling a number of sheets to form a document comprises a support station, a stacker to receive a stream of sheets and to deposit them one above the other in a stack at the support station, and a carrier to move an assembled document away from the support station, the support station including two sets of blades arranged to support opposite sides of the sheets with each set including at least two blades and a rotary drive for counter rotating the sets of blades to lower and dump the assembled document supported by the blades between the sets of blades and onto the carrier, rotation of the sets of blades also moving the next blades of the two sets into position to receive the following sheets from the stacker to form the next document. Preferably each set of blades comprises four blades arranged in a cruciform shape.In this case, the next blades in each set are upright and serve to locate and register the edges of the sheets of each document. Each set of blades may extend along the whole side of the sheets or there may be two or more separate sets of blades arranged on common shafts at opposite sides of the sheets to support the opposite sides of the sheets.

Preferably the separation of the sets of blades on opposite sides of the sheets is adjustable to enable the assembler to accommodate sheets of different size. Usually the sets of blades are arranged to support the two longest sides of the sheets although it is possible to support the shorter sides. When the sets of blades are formed by separate sets mounted on common shafts the separate sets are preferably adjustable along the shaft to take account of differences in the size of the sheets.

Preferably the rotary drive for counter rotating the sets of blades to lower the dump the assembled document is arranged to rotate the sets of blades to a predetermined part of a revolution to bring the next blade into the sheet receiving position. In practice, when the sets of blades each include four blades, the rotary drive is arranged to rotate each set of blades by a quarter of a revolution. The rotary drive to achieve this partial revolution of the sets of blades may include individual stepping motors connected to the sets of blades which are connected together electrically to ensure that they counter rotate as the same time or, alternatively, the rotary drive may include an electric motor and a part revolution clutch.

Preferably the stacker to receive a stream of sheets and deposit them one above the other in a stack at the support station comprises a wheel containing a number of arcuate generally radially extending slots and an abutment surface extending below and generally parallel to the axis of the wheel. These sheets are fed to the slotted wheel by a conveyor and the leading edges of the sheets are received in the slots in the wheel. The rotation of the slotted wheel turns the sheets over and brings their leading edges into contact with the abutment surface. This abutment surface prevents further rotation of the leading edgesof the sheets about the rotary axis of the wheel and thus, further rotation of the slotted wheel releases the sheets from its slots allowing them to fall into a stack in the support station one above the other.A guide plate may be provided opposite the abutment surface to register the trailing edges of the sheets. Additional guides may be provided at the sides of the sheets to provide registration for the sides of the sheets and this is particularly preferred when the sets of blades in the support station do not include four blades in each set.

Another stacker which may be used is a rotating suction wheel which consists of a drum with air holes arranged around its circumference with a vacuum applied to the drum. The sheet of paper fed to the drum is held by this suction and as the drum rotates the sheet of paper is turned over and dropped onto the stacking station. Otherwise, a conventional sucker cup orgrippersystem can be used as in a conventional printing machine.

Preferably the carrier to move the assembled documents away from the support station is formed by a conveyor having a flat fixed bed with movable dogs upstanding above the surface of the bed.

Preferably the dogs are arranged to move stepwise once an assembled document has been deposited on the flat bed for the support station. The document assembler preferably includes means to feed front covers to the conveyor upstream from the support station and means to feed rear covers to the assembled document downstream from the support station to complete the assembly of the documents.

The conveyor may also include a reject portion formed by a pivoted portion of the flat bed which can be lifted to tip an incorrectly assembled document or a document containing an incorrectly printed or processed sheet off the conveyor into a reject bin.

The location ofthe sets of blades in a vertical direction may be adjustable to take account of the number of sheets to be assembled in each document and when the stack is formed by a slotted wheel it has been found that it is preferred that the blades to not lie in a horizontal plane. Instead it is preferred that the blades are inclined to the horizontal direction with the leading edge of the sheets lower than their trailing edges. Preferably sheets are released from the slotted wheel such that each sheet momentarily lies in a plane at an angle to the horizontal plane. This angle is substantially a tangent to the slotted wheel at the point at which the leading edge of the sheet is released. Preferably the angle of the shafts should be adjusted to be parallel to this angle.

The combination of these two adjustments enable the sheets to be neatly assembled onto the blades, into a document. Preferably the attitude of the blades is also variable.

An example of the document assembler in accordance with this invention will now be described with reference to the accompanying drawings in which: Figure 1 is an isometric view of the document assembler; Figure 2 is an isometric view of the motor box; and, Figure 3 is a biock diagram of the path the sheets follow through the assembler showing the relationship between the components and the control system.

This example of a document assembler comprises a stacker 1 a support station 2 and a carrier 3. The stacker 1 includes a pair of slotted rotating wheels 4 which accept sheets fed in at a high speed from a printing machine track 5 and release the sheets onto the support station 2 comprising four sets of blades 6 arranged in a cross. The wheels 4 include arcuate slots 7 extending generally radially. As the slotted wheels 4 revolve with sheets held in the slots 7 the leading edges of the sheets are brought up against an abutting surface 8 parallel to the rotary axis of the wheels 4. As the slotted wheels 4 revolve the sheet is forced out of the slot 7 and falls onto the sets of blades 6.The sets of blades 6 are attached to shafts 9 and 10 and are adjustable in position along and fixed to shafts 9 and 10 by grub screws 11 to enable their position to be matched to different lengths of sheets.

The separation of the shafts 9 and 10 may be adjusted by sliding the shaft 9 along a slot 12 to take account of various widths of sheets. The shafts 9 and 10 are driven by a motor 13 mounted in a motor box 14. In use, the motor 13 rotates continuously. The drive motor 13 is coupled through a toothed belt 16 to a pulley 17 rotatably mounted on the shaft 10. The shaft 10 is driven via a wire wrap clutch 18 including a control sleeve 19 having abutment surfaces spaced at 90" about its periphery. A pawl 20 engages with the sleeve 19 to engage the abutment and prevent rotation of the sleeve 19. The pawl is coupled to a solenoid 21 which is actuable to move the pawl 20 to allow rotation of the sleeve 19.Upon release of the sleeve 19 the wire wrap clutch 18 couples the pulley 17 and the shaft 10 together to transmit the rotation of the pulley 17 to shaft 10 and the blades 6. Release of the pawl 20 engages the next abutment and hence disengages the drive pulley 17 from the shaft 10 after a quarter of a revolution. Shaft 10 is prevented from further rotation downwards by the panel 20.

A pulley 22 is connected to shaft 10 and to a double sided toothed belt 23 which is also connected to a pulley 24 connected to shaft 9 which drives shaft 9 to rotate in the opposite direction to shaft 10. The position of shaft 9 can be adjusted by releasing screws 25 and 26 and sliding shaft bearing mounts 27 (only one of which is shown) so that the shaft 9 moves in the slot 12 and slot 28 being locked into position by screws 25 and 26. A pulley 29 is used to adjust the tension of the belt 23 after adjustment of the shaft 9. It moves in a slot 30.

The angle of inclination to the horizontal of the shafts 9 and 10 is adjustable by pivoting the motor box 14 about a pivot 31 and locking the arrangement in the required position by a locking screw 32 in slot 33. The overall height of the blades 6 may also be adjusted by using alternative holes 34 in a bar 35 to provide the pivot 31. This facilitates the setting up of the arrangement to enable the shafts 9 and 10 to be set to the most efficient angle for the documents as they come out of the slotted wheels 4 and settle onto the blades 6. Guides 36 fixed, and 37 movable, ensure correct registration of the documents.

In action, a set of sheets forming a document are fed onto the support station 2 which supports the assembled document over the underlying bed 38.

Each shaft is then incremented through 90 , shaft 9 clockwise and shaft 10 anticlockwise (as seen in Figure 1 - described above) allowing the assembled document to drop onto the bed 38 between the shafts 9 and 10. It is vital that the shafts 9 and 10 rotate very rapidly to ensure that the next blades 39 move into position between the fall of two successive sheets onto the stack in the support station 2.

This ensures that the next blades are in position to start assembly of the next document, and do not strike the edge of the descending sheets being released from the slotted rotating wheels 4. It has been found that for reliable operation, the 90" rotation should take no more than 50 milliseconds when the sheets are fed into the slotted rotating wheels 4 at a rate of one every 125 milliseconds.

The assembled documents drop onto the carrier 3 which is formed by the fixed flat bed 38 with belts 40 and 41 having dogs 42 spaced in pairs at regular intervals wider than the widest sheet which it is intended to handle. The front covers are placed on the carrier 3 upstream of the support station 2 by a cover inserter mechanism (not shown).

The document is dropped on top of the cover and is moved along the track to a station where a rear cover is placed on top of the document by a cover inserter (again not shown). The document is then transported by the track to a stitching and binding machine or other finishing process. The conveyor may be driven in a stepwise manner by a stepping motor or through a clutch.

The carrier 3 includes a rotary solenoid operated reject flap 43 let into the surface of the track 38 downstream of the support station 2 but upstream of the second cover inserter. If an assembled document is known to contain a fault, for example a fault in the printing of one of the sheets as a result of a check carried out by a sensing and inspection means in the printing machine, then the document is rejected from the track before it is stitched and bound, by raising the flat 43 to cause the document to slide down, off the bed 38 into a reject bin (not shown).

The rejection of long documents may be assisted by a pin 44 connected under the track to the reject flap 43 and rising out of a hole 45.

The shafts 9 and 10, the rotating sectored wheels 4, the carrier 3 and reject flap 43 are synchronised and controlled by signals from a control circuit 46 incorporating a microprocessor or from a central computer controlling the entire document prepartion assembly. Such control means allow the number of sheets in a document to be easily varied from one document to the next.

Claims (9)

1. Adocumentassemblerforassembling a number of sheets to form a document, the assembler comprising a support station; a stacker to receive a stream of sheets and deposit them one above the other in a stack at the support station; and a carrier to move an assembled document away from the support station, the support station including two sets of blades arranged to support opposite sides of the sheets with each set including at least two blades and a rotary drive for counter rotating the sets of blades to lower and dump the assembled documents supported by the blades between the sets of blades and onto the carrier, rotation of the sets of blades also moving the next blades of the two sets into position to receive the following sheets from the stacker to form the next document.

2. An assembler according to claim 1, wherein each set of blades comprises four blades arranged in a cruciform shape.

3. An assembler according to claim 1 or claim 2, wherein two or more separate sets of blades are arranged on common shafts at opposite sides of the sheets to support the opposite sides of the sheets.

4. An assembler according to claim 3, wherein the separate sets of blades are adjustable relatively to one another along the common shafts to take account of differences in the size of the sheets.

5. An assembler according to any of the preceding claims, wherein the separation of the sets of blades on opposite sides of the sheet is adjustable.

6. An assembler according to any one of the preceding claims, wherein the rotary drive is arranged to rotate the sets of blades to a predetermined part of a revolution to bring the next blade into the sheet receiving position.

7. An assembler according to any of the preceding claims, wherein the location of the sets of blades in the vertical direction is adjustable.

8. An assembler according to any of the preceding claims, wherein the stacker comprises a wheel containing a number of arcuate generally radially extending slots and an abutment surface extending below and generally parallel to the axis of the wheel whereby rotation of the slotted wheel brings the leading edges of the sheets into contact with the abutment surface, further rotation of the wheel releasing the sheets from the slots and allowing them to fall into a stack in the support station one above the other.

9. An assembler according to claim 1, substantially as described with reference to the accompanying drawings.