AR-F12 (serv.man5). Puncher unit (option) basic operation - Sharp Copying Equipment Service Manual (repair manual). Page 6

The puncher unit is located on the feed path between the host machine and the finisher, and

successively punches holes when the paper stops temporarily. When the trailing edge of the paper
reaches the puncher unit, the inlet roller of the finisher unit temporarily stops the paper and holes are
punched on the trailing edge of the paper.

The puncher unit consists of a die and hole puncher (punch blade).
The hole puncher is driven by the punch motor (M1P). The hole puncher is attached to the

eccentric cam of the punch shaft, and rotary action of the punch shaft is converted to reciprocal
motion to perform punching.

Punch motor (M1P) is a DC motor. The home position of the punch shaft is detected by punch

home position sensor (PI3P). To stop the DC punch motor accurately at its home position, the punch
motor clock sensor (PI2P) counts a predetermined number of clock pulses to stop the punch motor. A
single punch operation is performed by rotating the punch shaft 180° from its home position.

Five light sensors (photosensor PCB) are located at the upper side of the inlet paper feed path of

the puncher unit and a set of five LEDs (LED PCB) are located at the lower side. These sensors and
LEDs function as five sensors. The frontmost sensor (LED5, PTR5) are the trailing edge sensor and
are used for detecting the trailing edge of the paper. The remaining sensors (LED1 to LED4, PTR1 to
PTR4) are horizontal registration sensors, and are used for detecting the inner position of the paper
for determining the hole punching position.

The punch motor, puncher unit and above sensors comprise the punch slide unit. This unit moves

backwards and forwards according to the size of the paper. Backward and forward movement is
driven by the horizontal registration motor (M2P). The home position of the punch slide unit is
detected by the horizontal registration home position sensor (PI1P). The horizontal registration motor
(M2P) is a 2-phase stepping motor.

The punch motor and horizontal registration motor is driven by the punch driver PCB according

to control signals from the finisher controller PCB.

Punch scraps caused by punching are stored in the punched scrap container. Scrap full detection

is performed by a reflective sensor (LED6 and PTR6 on the scrap full detector PCB unit).