Punching device for document processing machine

Abstract

To provide an improved creasing device that has a small footprint while being robust enough to handle sheets of dense quality and sheets other than paper or cardboard such as plastic sheets.SOLUTION: A perforation device (1) for a document processing machine comprises: a frame (2); a support member; and a blade member attached to the frame. The support member and the blade member are movable relative to each other. The support member is curved. The perforation device comprises a drive assembly configured to move the blade member and / or the support member in a rocking motion such that only a portion of the blade perforates the sheet. The portion of the blade member perforating the sheet moves along a length of the blade member as the rocking motion progresses.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to machines for processing documents including one or more sheets. In particular, the disclosure relates to a press assembly for pressing a blade against a sheet, thereby creating perforations in the sheet. [Background technology]

[0002] Document processing machines are widely used for post-processing of printed documents comprising one or more sheets of paper or plastic. At times, it is desirable to create linear perforations across a sheet, but it has been found that manufacturing a compact yet robust assembly for linear perforation of a sheet is not easy.

[0003] US 2169799A relates to a punching machine used to simultaneously punch multiple sheets of paper, the device being large and heavy and therefore difficult to fit into modern post-processing lines after a printer.

[0004] GB551569A relates to a machine for perforating paper or cardboard. The machine includes a mechanism for simultaneously pressing a blade and a support together to produce perforations in the paper or cardboard. The mechanism includes left and right levers connected via a rod, and a pivot mechanism on a stepped drive wheel that moves the mechanism in response to rotation of the stepped drive wheel. The machine is large, heavy, and complex, and therefore difficult to fit into a modern post-processing line after a printer.

[0005] US 4,444,080 A relates to a machine for perforating a paper web drawn between two rollers, one of which is equipped with a serrated / toothed blade extending along the length of the roller to which it is attached. This device is not suitable for perforating individual sheets, at least because it is difficult to control the position of the perforations on the sheet.

[0006] It is therefore a primary object of the present invention to provide an improved creasing device that has a small footprint and is robust enough to accommodate sheets other than paper or cardboard, such as high density sheets and plastic sheets. Summary of the Invention

[0007] According to a first aspect of the present invention, the first and other objects are achieved by a punching device as defined in claim 1, with certain alternative embodiments defined in the dependent claims. The punching device is for a document processing machine and comprises a frame, a support member, and a blade member attached to the frame. The support member and the blade member are movable relative to each other and configured to cooperate by movement between an open position in which a gap exists between the support member and the blade member for inserting a sheet, and a perforation position in which the gap is at least partially closed such that at least a portion of the sheet is pressed between the support member and the blade member, thereby perforating the sheet. The support member is curved, and the punching device comprises a drive assembly configured to move the blade member and / or the support member in an oscillating motion such that only a portion of the blade perforates the sheet, the portion of the blade member that perforates the sheet moving along the length of the blade member as the oscillating motion progresses.

[0008] The combination of curved support members or blades and the oscillating motion that moves them relative to one another allows the perforation line to be achieved progressively through the oscillating motion, with only a small portion of the blade members active at a time. This significantly reduces the force required to force the blade into the sheet and perforate it, thus allowing for an overall leaner design of the perforating apparatus while still being robust enough for the task at hand.

[0009] The drive assembly may include a rotatable shaft with a left cam member attached to the shaft at a left portion thereof and a right cam member attached to the shaft at a right portion thereof, and the blade member may be provided with a left cam follower configured to cooperate with the left cam member to control movement of the left portion of the blade member in response to rotation of the shaft, and a right cam follower configured to cooperate with the right cam member to control movement of the right portion of the blade member in response to rotation of the shaft.

[0010] The left and right cam members may each include a respective rotary bearing that defines a respective cylindrical cam surface. The rotary bearings are mounted off-center relative to the central axis of the shaft. The use of rotary bearings on the cam surfaces reduces wear on the cam followers because the cam surfaces simply roll on the cam followers rather than sliding past them. This extends the life of the cams and cam followers and reduces the need for servicing of the drilling device.

[0011] The left cam member may be mounted on the shaft with an angular offset to the right cam member relative to the central axis, the relative angular offset of the cam members providing for an oscillating motion while using the same cam member, thus allowing for a smooth and symmetrical oscillating motion.

[0012] The drilling device may further comprise a biasing means configured to urge the blade member and the support member apart. The biasing means urges the blade against the cam member so that the blade always follows the cam member without relying on gravity. Thus, the machine can be operated in all orientations.

[0013] According to a second aspect, there may be provided a document processing device comprising an integrated punching device as described above.

[0014] 1 to 4 show a drilling device according to a first embodiment of the invention in different positions. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 shows the punching device in an open position for receiving sheets to be punched. [Figure 2] FIG. 2 shows a series of alternating left and right rocking movements starting with drilling on the right side in FIG. [Figure 3] FIG. 3 shows a series of alternating rocking movements, moving gradually to perforate the central portion in FIG. [Figure 4] FIG. 4 shows a series of alternating rocking movements that ultimately perforate the left portion in FIG. [Figure 5] 5 shows a schematic side view of a shaft provided with left and right cam members, which are angularly offset relative to the axis of rotation of the shaft to jointly control movement of the support member upon rotation of the shaft through said rocking motion and further to the open position.

[0016] [Table 1] DETAILED DESCRIPTION OF THE INVENTION

[0017] A first embodiment of a perforation device will be described below with reference to the accompanying drawings. The perforation device 1 is for a document processing machine, such as a printer or copier. The perforation device 1 is used to perforate sheets of paper, plastic, or similar material typically used for printed information, flyers, booklets, and the like. The perforation device 1 comprises a frame 2, a support member 3, and a blade member 4 attached to the frame 2, the support member 3 and the blade member 4 being movable relative to one another and configured to cooperate by movement between an open position in which a gap 5 for inserting a sheet exists between the support member 3 and the blade member 4, and a perforation position in which the gap is at least partially closed, such that at least a portion of the sheet is pressed between the support member 3 and the blade member 4, resulting in the sheet being perforated. To achieve perforation along only a portion of the length to be perforated, the support member 3 is curved, as shown in FIGS. 2 to 4, and is moved so that the portion of the curve closest to the blade member 4 changes from left to right and vice versa. The smaller contact length / area now active to perforate the sheet requires a lower pressure than would be required if the entire length of the perforations were active simultaneously. To effect relative movement between the blade member 4 and the support member 3, the perforating device 1 comprises a drive assembly configured to move the blade member 4 and / or the support member 3 in an oscillating motion such that only a portion of the blade member 4 perforates the sheet. The portion of the blade member 4 that perforates the sheet moves along the length of the blade member 4 as the oscillating motion progresses.

[0018] The drive assembly includes a rotatable shaft 6 with a left cam member 7 attached to the shaft 6 at a left portion thereof and a right cam member 8 attached to the shaft 6 at a right portion thereof. The blade member 4 is provided with a left cam follower 9 configured to cooperate with the left cam member 7 to control movement of the left portion of the blade member 4 in response to rotation of the shaft 6. The blade member 4 is also provided with a right cam follower 10 configured to cooperate with the right cam member 8 to control movement of the right portion of the blade member 4 in response to rotation of the shaft 6. A drive motor (not shown) drives a belt 14 (see FIG. 1 ), which drives the shaft 6. In other embodiments, any other suitable drive means may be used to rotate the shaft 6.

[0019] The left cam member 7 and the right cam member 8 each include a respective rotary bearing 11 defining a respective cylindrical cam surface, where the rotary bearing 11 is mounted off-center relative to the central axis 12 of the shaft 6. In other embodiments, a fixed profile defining the cam's guide surface may alternatively be mounted to the shaft 6 in place of the rotary bearing 11, however this would increase friction and wear on the cam follower compared to an easily rotatable rotary bearing 11.

[0020] As shown in Figure 5, the left cam member 7 is mounted to the shaft 6 with an angular offset 13 to the right cam member relative to the central axis 12. The angular offset allows the left and right portions of the support to be offset differently from the blade at any given rotational position of the shaft 6, thereby providing an oscillating motion when the shaft 6 is rotated.

[0021] The drilling device 1 also includes biasing means 14 configured to push apart the blade member 4 and the support member 3. In this embodiment, one coil spring is provided to push apart the left portion of the support member 3 and the blade, and another coil spring is provided to push apart the right portion of the support member 3 and the blade member 4.

[0022] The punching device 1 is typically attached to a document processing device such as a printer, and may be manufactured and sold as an integrated system. The following is a summary of the claims originally proposed in the present application. [1] A punching device (1) for a document processing machine, the punching device (1) comprising a frame (2), a support member (3), and a blade member (4) attached to the frame (2), the support member (3) and the blade member (4) being movable relative to each other and having an open position in which a gap (5) for inserting a sheet exists between the support member (3) and the blade member (4), and a closed position in which at least a portion of the sheet is pressed between the support member (3) and the blade member (4), so that the sheet is perforated. A perforating device (1) configured to cooperate by movement between a perforation position where the gap is at least partially closed and a perforation position where the support member (3) is curved, the perforating device (1) comprising a drive assembly configured to move the blade member (4) and / or the support member (3) in an oscillating motion so that only a portion of the blade perforates the sheet, the portion of the blade member (4) that perforates the sheet moving along the length of the blade member (4) as the oscillating motion progresses. [2] The drive assembly comprises a rotatable shaft (6), a left cam member (7) attached to the shaft at a left portion of the shaft (6), and a right cam member (8) attached to the shaft at a right portion of the shaft (6); the blade member (4) is provided with a left cam follower (9) configured to cooperate with the left cam member (7) to control movement of the left portion of the blade member (4) in response to rotation of the shaft (6); The drilling device (1) described in [1], wherein the blade member (4) is provided with a right cam follower (10) configured to cooperate with the right cam member (8) to control movement of the right portion of the blade member (4) in response to rotation of the shaft (6). [3] The drilling device (1) described in [2], wherein each of the left cam member (7) and the right cam member (8) has a respective rotary bearing (11) defining a respective cylindrical cam surface, and wherein the rotary bearing (11) is mounted off-center with respect to the central axis (12) of the shaft (6). [4] A drilling device (1) according to [2] or [3], wherein the left cam member (7) is attached to the shaft (6) with an angular offset (13) to the right cam member relative to the central axis (12). [5] The drilling device (1) according to any one of [1] to [4], further comprising a biasing means (14) configured to push apart the blade member (4) and the support member (3). [6] A document processing device equipped with the punching device (1) according to any one of [1] to [5].

Claims

1. A punching device (1) for a document processing machine, the punching device (1) comprising a frame (2), a support member (3), and a blade member (4) attached to the frame (2), the support member (3) and the blade member (4) being movable relative to each other and having an open position in which a gap (5) for inserting a sheet exists between the support member (3) and the blade member (4), and a closed position in which the gap is narrowed so that at least a portion of the sheet is pressed between the support member (3) and the blade member (4), resulting in the sheet being perforated. a support member (3) configured to cooperate with the sheet by movement between an open and partially closed perforation position, the support member (3) being curved in the length direction of the support member (3), the perforating device (1) comprising a drive assembly configured to move the blade member (4) and / or the support member (3) in an oscillating motion such that only a portion of the blade perforates the sheet, the portion of the blade member (4) that perforates the sheet moving along the length of the blade member (4) as the oscillating motion progresses.

2. The drive assembly comprises a rotatable shaft (6), a left cam member (7) attached to the shaft at a left portion thereof, and a right cam member (8) attached to the shaft (6) at a right portion thereof; the blade member (4) is provided with a left cam follower (9) configured to cooperate with the left cam member (7) to control movement of the left portion of the blade member (4) in response to rotation of the shaft (6); 2. The drilling device (1) of claim 1, wherein the blade member (4) is provided with a right cam follower (10) configured to cooperate with the right cam member (8) to control movement of the right portion of the blade member (4) in response to rotation of the shaft (6).

3. 3. The drilling device (1) of claim 2, wherein the left cam member (7) and the right cam member (8) each include a respective rotary bearing (11) defining a respective cylindrical cam surface, wherein the rotary bearing (11) is mounted off-center with respect to a central axis (12) of the shaft (6).

4. 4. Drilling device (1) according to claim 2 or 3, wherein the left cam member (7) is mounted on the shaft (6) with an angular offset (13) to the right cam member relative to the central axis (12).

5. The drilling device (1) according to any one of claims 1 to 4, further comprising biasing means (14) configured to push the blade member (4) and the support member (3) apart.

6. A document processing device comprising a punching device (1) according to any one of claims 1 to 5.

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