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The stitching system “stitches” the center of an output stack with staples.
To enable stitching at two locations on a stack, two stitcher units (front, rear) are used. Each

stitcher unit is equipped with a stitcher motor (M7S, M6S) for drive, a stitcher home position sensor
(MS7S, MS5S) for detection of position and a staple sensor (MS6S, MS4S) for detection of the
presence/absence of staples.

The stitcher base is designed so that it may be drawn out to the front from the saddle stitcher for

replacement of the staple cartridge or removal of a staple jam. The stitcher unit in sensor (PI16S) is
used to make sure that the stitcher base is properly fitted to the saddle stitch unit.

Safety switches are not mounted for the saddle stitch unit (front, rear), as the location does not

allow access by the user.

Stitcher (rear)

Stitcher (front)

Stack

The stitcher base unit consists of two stitchers and stitcher bases. The stitchers are fixed in posi-

tion, and are not designed to slide or swing.

Stitching is executed by driving the rotary cam by the stitcher motor (M7S, M6S). The front and

rear stitcher units are operated with a time delay so as to prevent wrinkling of paper and to limit the
load applied to the power supply. (A time delay for initiating the stitcher motor startup current helps
decrease the load on the power supply.)

The stitcher home position sensor (MS7S, MS5S) is used to monitor the movement of the rotary

cam, enabling identification of individual stitcher operations. The presence/absence of staples inside
the staple cartridge fitted to the stitcher is detected by the staple sensor (MS6S, MS4S).

The alignment plates keep both edges of the stack in place while stitching takes place.

(MS7S)

(MS5S)

 (PI18S)

Stitcher home position sensor 
(front)

Stitcher motor (front) (MS7)

Stitcher motor (rear) (M6S)

Stitcher home position 
sensor (rear)

No.1 paper sensor

Alignment motor (M5S)

Alignment

Escape

Cam

Mount

The paper folding mechanism consists of a guide plate, paper folding rollers, paper pushing

plate, and paper positioning plate.

The guide plate is used to cover the folding rollers while sheets are output so as to prevent sheets

from coming into contact with the folding rollers during output. Before the stack is folded, the guide
plate moves down to enable the folding rollers to operate.

The folding rollers are driven by the paper folding motor (M2S), and the drive of the motor is

monitored by the paper folding motor clock sensor (PI4S). The mechanism is also equipped with a
paper folding home position sensor (PI21S) for detecting the position of the paper folding rollers.

The paper pushing plate is driven by the paper pushing plate motor (M8S), and the drive of the

paper pushing plate motor is monitored by the paper pushing plate motor clock sensor (PI1S). The
paper pushing plate home position sensor (PI14S) and the paper pushing plate top position sensor
(PI15S) are used to detect the position of the paper pushing plate.

After being folded into two by the paper folding rollers, a stack is moved ahead by the delivery

roller for delivery. The delivery roller is driven by the paper folding motor. The delivery sensor
(PI11S) is mounted to the delivery assembly to detect delivery of paper. The tray paper sensor (PI6S)
is used to detect the presence/absence of paper on the tray, but does not detect jams. The vertical path
paper sensor (PI17S) serves to detect the presence of paper after jam removal.