GB2285968A

GB2285968A - Compiler tray for sheets

Info

Publication number: GB2285968A
Application number: GB9401073A
Authority: GB
Inventors: Jeff Ryan; Peter Alan Mayfield; Brian Whaites
Original assignee: Xerox Corp
Current assignee: Xerox Corp
Priority date: 1994-01-20
Filing date: 1994-01-20
Publication date: 1995-08-02
Anticipated expiration: 2014-01-20
Also published as: GB9401073D0; GB2285968B

Abstract

A compiler for an image reproduction machine includes a roll pair 4, 6 for feeding each of a set of output sheets 10 into a compiler tray 12, the compiler tray being pivotable about an axis 36 parallel to the plane of the tray; a flexible rubber belt 20 associated with the roll pair, for aligning the output sheets through a friction feeding action with a registration wall of the compiler tray; and a spring bias 38 for resiliently urging the sheet-receiving surface of the tray towards the aligning means, thereby assuring alignment of the set of sheets. <IMAGE>

Description

COMPILER TRAY The present invention relates to a finisher stage for copying and printing machines, and more particularly to an improved compiler tray for such devices.

Conventional copying machines often include a compiler tray in which two or more output sheets which comprise a set are compiled, in accurate registration, with a stapling head, associated with the tray, being provided to enable optional stapling of the set prior to removal of the set of sheets by a user. In certain cases, the compiler tray may itself form the output or catch tray for the copying and printing machine.

A copying machine incorporating a prior art finisher stage is shown in Fig. 1. The finisher 5, which is described in more detail in UK patent application No. 8226819 filed 21 September 1982, includes an offsetting catch tray or output tray 460 and may be operated (a) to compile, register and corner staple sets of copies as they are produced and transport the stapled sets into the offsetting catch tray 460, and (b) to deliver copies direct to the offsetting catch tray 460 where the sheets may be compiled in offset sets. In a variation of (a) the stapling step may be omitted.

The finisher 5 receives copy sheets from the processor at input nip 465 and conveys tnem to the offsetting catch tray 460 either directly along a path 461 or, via a compiler tray 462 In wnich they are registered and stapled, along a path 463. The direction of the sheets Is determined by a diverter 464 located directly following the finisher input nip rolls 465a,465b and which Is operated In response to a signal from the processor Initiated by the operator.

The path 463 comprises upper and lower guides 463a, 463b and includes two further sets of nip rolls 467, 468 which accelerate the sheets Into the compiler tray 462. The sheets are corner registered against a retractable end registration gate 469 and a side registration gate 470 at the front of the machine by gravity and a paddle wheel 471, represented in Figure 3 by a broken ellipse Sets compiled in the tray 462 are corner stapled by a stapler 472. Stapled sets are driven from the tray 462 by retracting the gate 469 and lifting the set against a pair of driven eject rolls 473 by means of a pair of idler rolls 474 mounted on one end of pivoted arm 475 which carries the gate 469 at its other end Ttiiis the sheets are conveR,ez Into ine compiler tray In a first direction (from right to left in Fig 1) and their trail edges registered by being conveyed against the end registration gate 469 in the opposite direction (from left to nght in Fig.1). The path 463 extends over the paddle wheel 471 and the eject rolls 473 and the sheets drop by gravity towards the end registration gate 469 since the tray 462 slopes downwardly in that direction suitably at an angie of about 40 degrees.

The sets are carried into the offseting catch tray 460, which is arranged beneath the compiler tray 462, around a large driven, rigid sun roll 476 with the aid of three driven, compliant planet rolls 477, 478, 479 and outer guides 480, 481. Thus as the sets are conveyed to the offsetting catch tray 460 they are inverted and their direction reversed. The catch tray 460 itself slopes downwardly in the same direction as the compiler tray 462, suitably at about 40 degrees.

A drawback of such finist;ers is the need to provide a separate means (6.cm. paddle wheel 471 in Fig.1) to produce corner registration of the set of sheets (prior to stapling).

It is also known to use a flexible rubber belts to assist with registration in a gravity stacked compiler tray: at the last paper feeding nip before the compiler tray (e.g. formed by rolls 468 in Fig.1), one or more rotating flexible belts friction feed the (top) sheet in the tray towards and against a registration wall of the tray.

However, while such belt assisted compiler trays work effectively for sets of up to about 25 sheets, problems are encountered with the use of such trays when sets with higher numbers of sheets are Involved. Typically, the recirculating document handler of a modern copying machine is capable of handling an original document of up to 50 pages. But, due to the thickness of the paper, by the time the number of copies In the compiler tray has exceeded about 30, the overall thickness of the set is sufficient to appreciably deform the cross-section of the belts Into an oval shape The result S that the angle of incidence made by the incoming (top) sheet with the contacting portion of the belts is reduced, so that feeding efficiency of the belts is significantly reduced, particularly with Incoming sheets which have a degree of upcurl at their leading edge. Accordingly, the later-copied sheets in such a set may not be properly registered in the compiler at all.

The present invention provides a compiler for an image reproduction machine, comprising: means for feeding each of a set of output sheets into an compiler tray, the compiler tray being rotatable about an axis parallel to the plane of the tray; means for aligning the output sheets with a registration wall of the compiler tray; and means for resiliently urging the tray towards the aligning means, thereby assuring alignment of the set of sheets.

Advantages of this construction include the low cost, the need for fewer moving parts and the fact that no extra motors are sensors are required to solve the above-mentioned problem.

Preferably, the compiler tray is inclined at an angle to the horizontal. Preferably, the tray Is rotatable through a range of angles to the horizontal in dependence upon the number of copy sheets present in the tray. Preferably, the tray is rotatable through a range of angles to the horizontal of about 35-45 .

In one embodiment the urging means comprises a tension spnng having one end attached to a fixed point, and the other end attached to a point on the tray spaced from the axis of rotation by a distance of about 10-40-t of the length of the tray.

The urging means may comprise a torsion spring mounted about said axis of rotation.

Preferably, the aligning means includes one or more rubber belts rotatable about the lower roll of a respective pair of rolls defining an output nip.

The present invention further provides a copying or pnnting machine incorporating a compiler according to any of the preceding claims.

The present Invention further provides a compiler substantlally as hereinbefore described with reference to Figs 2 and 3 of the accompanying drawings.

The present invention further provides a copying or printing machine substantially as hereinbefore described with reference to Figs 1 to 3 of the accompanying drawings.

Emiwdlments of the invention will now be described, by way of example, with reference to the accompanying drawings, In which: Figure 1 is a cross-sectional view of a prior art copying machine Incorporating a compiler tray; Figure 2 is a plan view of a compiler according to an embodiment of the invention; and Figure 3 is a partial cross-sectional view of the compiler of Fig. 2.

Referring to Fig. 2, this shows a plan view of a compiler, generally designated 2, from which certain parts have been omitted for clarity. The compiler 2 Includes three pairs of rolls 4,6, corresponding to rolls 468 in Fig 1, driven by motors and belts In the conventional manner under the control of the machine's central processor (not shown), with each pair of rolls 4,6 defining a nip 8 through which output copy sheets 10 are fed in the direction of arrow A The sheets 10 are each fed onto the flat surface 12 of the compiler tray 14 whereafter they are urged back (in the direction of arrow B) towards a first registration wall 16 of the tray 14 by the action of gravity (since the tray 14 is inclined at about 35-45 to the horizontal), and optionally by the friction feeding action of rollers 18 which may driven in a conventional manner under the control of the machine's central processor (not shown) As will be described in further detail below, rubber belts 20, having ribs or corrugations on their outer surface assist In aligning all the sheets In a set against the first reg;stration wall 16. Although it has been found possible to use only two belts 20 as shown, any number many be used in any arrangement (e.g., one on the centre rolls; or one on each of the outer rolls) which achieves the desired sheet registration. In order additionally to provide registration in a direction perpendicular to arrow B, a tamper 24 is provided which is slidably moveable in a slot 26 in the tray 14 in a conventional manner under the control of the machine's central processor (not shown). When the tamper 24 is actuated (after each or all of the sheets 10 have been received In the tray 14), the planar surface 27 thereof abuts the edge 28 of the sheet(s) and pushes them In the direction of arrow C until they are aligned with a second registration wall 30 of the tray 14 Thus, the complete set of sheets is registered In the bottom right corner of the tray 14, whereafter the set can optionally be stapled by means of a conventional stapler head 32.

Figure 3 best shows the operation of the pivoting tray 14 and belts 20 in the compiler 2 of Fig. 2.

For each of the sets of rolls 4,6, a respective rubber belt 20, having a diameter several times larger than the rolls 4,6, completely encircle the lower roll 6 and are rotated by the action of the nip 8. The part 34 of each belt 20 which is remote from the nip 8 contacts either the planar surface 12 of the tray 14 (solid line), or, in use, the (top) copy sheet 10 present in the tray 14 (dotted line). The rotating motion of the belts causes frictional feeding of each sheet 10 to make the final alignment of the sheets 10 with the wall 16. In order to cope with larger sets of sheets (e.g. 30-50 sheets), the tray 14, rather than being fixed, is mounted so as to be rotatable, through a relatively small angle of travel (about 10-15 ) about an axis 36. The tray 14 is continuously urged towards the belts 20, by a springs 38 (on at each end of the tray 14) which have one end attached to a fixed point 40 in the machine, and the other attached to a point 42 on the tray 14 spaced a short distance (e.g. 10-40%) of the length of the tray 14) from the axis 36. The effect of this is to provide a relative small restonng torque on the tray 14 so as to urge the sheets against belts 20 only gently, and thus avoid deformation of the latter. It will be appreciated that the force could equally be applied using one or more torsion springs mounted about the axis 36 For the purposes ot explanation, in Fig 3 a gap is snown between the upper one of the sheets 10 (when the tray Is in the loaded condition - dotted Iine) and the belt 20.

Dunng operation, the tray can rotate from an angle of about 35 to the horizontal, to about 45" to the horizontal, as the tray is loaded up with sheets (for example numbenng over 30), such that the end of the tray may undergo a vertical displacement d of about 8-10mm.

Throughout this movement of the tray, the top sheet 10 is maintained in optimum contact with the belts 20, thus assuring that it Is transported into proper alignment with the wall 16 prior, for example, to a corner stapling operation and/or removal by a user.

Claims

CLAIMS:

1. A compiler for an image reproduction machine, comprising: means for feeding each of a set of output sheets into an compiler tray, the compiler tray being rotatable about an axis parallel to the plane of the tray; means for aligning the output sheets with a registration wall of the compiler tray; and means for resiliently urging the tray towards the aligning means, thereby assuring alignment of the set of sheets 2. A according to claim 1, wherein the compiler tray is inclined at an angle to the horizontal.

3 A according to claim 1 or 2, wherein the tray is rotatable through a range of angles to the horizontal in dependence upon the number of copy sheets present in the tray.

4 A according to claim 1, 2 or 3, xnerem the tray Is rotatable through a range of angles to the horizontal of about 35-45" 5 A according to any of the preceding claims, wherein the urging means comprises a tension spring having one end attached to a fixed point, and the other end attached to a point on the tray spaced from the axis of rotation by a distance of about 10-40 ,0 of the length of the tray 6 A according to any of claims 1 to 4, wherein the urging means comprises a torsion spnng mounted about said axis of rotation 7 A according to any of the preceding claims, wherein the aligning means includes one or more rubber belts rotatable about the lower roll of a respective pair of rolls defining an output nip.

a A copying or printing machine ntcrporatmg a compiler accoraing to any of the preceding claims 9. A compiler substantially as hereinbefore described with reference to Figs 2 and 3 of the accompanying drawings.

10. A copying or printing machine substantially as hereinbefore described with reference to Figs 2 and 3 of the accompanying drawings