SHEET REGISTRATION APPARATUS

Abstract: Apparatus for registering one or more sheets (1) in a registration position defined for example in a corner formed by two edge stops (3,4) comprises a sheet support member (2) and a tamping member (6) adapted to engage the edge or edges of the sheet or sheets on the support member. The tamping member is mounted on the end of an arm (8) which is mounted for angular movement about a shaft (9). On movement of the arm the tamper (6) moves so as to push the sheet(s) into the registration position. The tamping member (6) comprises a brush the bristles of which engage the edge(s) of the sheet(s).

Description: This invention relates to an apparatus for registering one or more sheets in a registration position. The invention is particularly, although not exclusively, useful in an apparatus, such as the finisher of a xerographic copying machine, in which a stack of sheets needs to be accurately registered, and tamped into a neat stack, before delivery to an output tray, or before the insertion of a staple by a stapling mechanism. One of the simplest ways of registering a stack of sheets is to push the stack towards its registration position, which may be defined either by a single edge stop or by two edge stops which constitute a corner. If a rigid pusher or tamper is used, there is the disadvantage that damage may occur to the sheets. A tamper having a surface which is soft enough not to damage the sheets will typically be liable to be damaged by the edges of the sheets. It is an object of the present invention to provide an apparatus for registering sheets in which these disadvantages are overcome. According to the present invention, there is provided an apparatus for registering one or more sheets in a registration position comprising a sheet support member having a plane whereon the sheet lies, a tamping member adapted to engage an edge of the, or each, sheet on the support member, and means to cause the tamping member to move so as to push the sheet or sheets into the registration position, characterised in that the tamping member comprises a brush the bristles of which extend through said plane and engage an edge of the, or each, sheet. The apparatus of the invention has the advantage that the brush is rigid enough to move paper sheets without damaging them, is sufficiently compliant to accommodate paper size tolerances, and shows very little wear. US-A-3,970,299 discloses a sheet registration device in which a brush rotates about a fixed axis with its bristles engaging the top surface of the sheet. This device is suitable only for registering single sheets, whereas the apparatus of the invention is also suitable for tamping a stack of sheets. An apparatus in accordance with the invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a diagrammatic plan view of part of a finisher of, for example, a xerographic copying machine, incorporating the apparatus of the present invention, with a paper sheet delivered thereto, but in an unregistered position; Figure 2 is a similar view to Figure 1, shown after operation of the registration apparatus of the invention, with a paper sheet in the registered position; and Figure 3 is an elevational view of part of the apparatus of Figure 1, showing the brush tamping member of the invention. Referring to the drawings, a paper sheet 1 is delivered to a sheet support member such as a tray 2, from the output of a machine such as a xerographic copying machine (not shown). The paper sheet 1 may be delivered either from the left or the right of the drawing as seen in Figures 1 and 2, or from above, for registration in the corner defined by the two edge stops 3 and 4 which are right angles to one another. The tray 2 may slope downwards towards the right-hand side of the Figures, i.e. towards edge stop 3, so that sheets delivered into the tray will tend to come to rest in the position shown in Figure 1. In the corner defined by edge stops 3 and 4, i.e. the lower right-hand corner of the tray 2, as viewed in Figures 1 and 2, a stapling mechanism 5 is positioned so that its jaws straddle the corners of a stack of sheets delivered onto the tray 2 and positioned as shown in Figure 2, in the registration position. In order to move a stack of sheets to the registration position (Figure 2) from the delivery position (Figure 1) a tamper 6 is used. Tamper 6 projects upwardly through a curves slot 7 in the tray 2, and is mounted at the end of an arm 8 which is pivotally mounted at its other end on a motor driven shaft 9. On actuation of the motor, arm 8 is rotated anticlockwise, causing tamper 6 to move to the position shown in Figure 2, thereby pushing the sheets into the registration corner. Alternatively, the other end of arm 8 may be mounted on a cam follower which is spring-urged into engagement with a camming surface. The camming surface is so shaped that on rotation it moves the cam, and hence the tamper 6 at suitable speeds. Thus, for example, the tamper may be moving relatively slowly as it engages a sheet edge and as the sheet approaches the registered position. The tamper 6 consists of a brush, only the bristles of which protrude through the slot 7 in the tray 2. The resilience of the bristles accommodates variations in sheet size, and prevents damage to the sheet edges. It is found that the brush bristles show very little wear. In a preferred mode of operation of the apparatus, the tamper is activated once for each sheet delivered into the tray 2, so that an accurately tamped and registered sheet stack is formed. Alternatively, for small stacks, all the sheets in a stack may be first delivered, and then the whole stack tamped. Furthermore, the apparatus is suitable for the registration of single sheets. Although an arcuate motion of the tamper 6 has been described, it might equally make a linear motion, either at right angles to a registration edge, or inclined to it at some other angle.

Claims: Apparatus for registering one or more sheets (1) in a regstration position comprising a sheet support member (2) having a plane whereon the sheet lies, a tamping member (6) adapted to engage an edge of the, or each, sheet on the support member, and means (8) to cause the tamping member to move so as to push the sheet or sheets into the registration position, characterised in that the tamping member (6) comprises a brush the bristles of which extend through said plane and engage an edge of the, or each, sheet. The apparatus of claim 1 wherein the tamping member (6) is mounted at one end of an arm (8) which is arranged to make angular movements about its other end. The apparatus of claim 2 wherein said other end of the arm is mounted on a shaft (9) driven by a motor. The apparatus of claim 2 wherein said other end of the arm (8) is mounted on a cam follower, and wherein the cam follower is spring-urged into engagement with a movable camming surface. The apparatus of any one of claims 2 to 4 wherein said sheet support member (2) is a tray member, and wherein the brush bristles protrude through a slot (7) in said tray member. The apparatus of claim 5 wherein said slot (7) is an arcuate slot having a radius appropriate to the length of said arm (8).

Inventors: GRAY, JOHN REGINALD
Applicants: XEROX CORPORATION
Application year: 1988
Main classification: G03G15
IPC codes: B65H9, G03G15