The present invention relates to devices for collating, stacking, and stapling sheets output from office equipment, such as copiers or printers.
With office equipment such as copiers and printers, it is common to provide xe2x80x9coutput devices,xe2x80x9d that is, devices which stack, collate, or staple output sheets into organized sets. A common feature of such output devices is a device known as a xe2x80x9cdisk stacker,xe2x80x9d in which there is provided a rotatable disk having a prong extending from the edge thereof. Sheets that are output from the printer or copier are placed in the throat between the prong and the rest of the desk, and the disk is rotated, carrying the sheet toward a stack of previous prints. In this way, the disk stacker can both collate and invert sheets which are output from the printer or copier.
A desirable feature of printers and copiers is the ability to staple sets of sheets which are output. Typically, immediately after a set of sheets is accumulated by, for instance, the disk stacker, the set is placed in proximity to a stapler head, which places a staple through the set. More advanced output devices are capable of placing staples in multiple positions along the edge of a set, so that, for example, a single output device can place a single staple in the corner of a set, or alternately placing two staples along one edge of the set, to yield a booklet-like output.
A common design challenge for output devices is to coordinate the placement and functions of a disk stacker and a stapling device within the same output device. In particular, in an advanced device, which is capable of placing single staples or double staples in a set, it may be necessary to move the stapler heads to the desired positions so that the staple is placed in the desired position on the set. This necessity to move the staple head may interfere with the architecture and function of other aspects of the output device, such as the disk stacker. Further, with a movable stapler head within the output device, the needed to accommodate other features of the output device may result in design compromises which can result in, for example, the sets being improperly skewed as they enter the output tray.
The present invention is directed toward a design of an output device, which is capable of placing a single corner staple or dual staples in a set, which overcomes some particular design difficulties.
U.S. Pat. No. 5,842,624 discloses a typical design of a stapler unit in an output device, in which the stapler head can move relative to the set, thereby placing the staple in the set at one or more selected locations.
U.S. Pat No. 5,188,353 discloses a typical design of a disk stacker, in particular one that includes a tamping mechanism which enables the disk stacker to provide small offsets of alternating sets output by the device.
According to the present invention, there is provided an apparatus for retaining a plurality of sheets in a position for stapling and for transferring a stapled set of sheets to an output location. A kicker contacts the set of sheets at an edge thereof. The kicker defines a first contact point and a second contact point, the second contact point being movable relative to the first contact point along the edge of the set of sheets. The kicker is urged against the set of sheets, thereby causing the kicker to push the set of sheets toward the output location.