Sharp AR-SS2 Service Manual page 27

When the lead cam rotates and the roller moves up and down along
the lead cam, the bin connected with the bin frame and the roller is
moved up and down.
Roller
Lead cam
Roller
If, however, all the grooves in the lead cam were slanted, the lead
cam would be rotated by the weight of the bin unit when the bin unit is
stationary. To prevent against this, the groove has the horizontal
section as shown below. The lead cam home position sensor detects
the position so that the roller comes at the horizontal section when
the bin unit is stationary.
Bin
Horizontal section
Lead cam home
position sensor (PI2)
3) Bin shift motor control
The bin shift motor control circuit is shown below.
The bin shift motor (M1) is a DC motor, and controlled by the drive
circuit to move the bin unit up and down.
The up/down moving speed of the bin unit is detected and controlled
by the shift motor clock sensor.
The stop position of the bin unit is detected by the lead cam home
position sensor.
When the stapler unit is not in the home position, the +24V power is
interrupted by the stapler home position switch to stop the bin shift
motor in order to prevent against a crash of the bin unit and the
stapler unit.
An overrun is prevented by the bin unit upper limit sensor and the
lower limit sensor.
The current detection circuit is provided to detect an overcurrent when
the bin unit is interrupted by a foreign material. It stops the bin unit at
that time.
9 – 8
AR-SS2