Polaroid ProCam Repair Manual page 31

In of Figure 1-24B, the Motor drives the Timing Gear and the cam on the face of
the Timing Gear forces EOC/S9 down, making contact with VER. With EOC/S9
closed, the Motor will continue to run. Once the cam face moves away from
EOC/S9, the Switch contacts open, the Motor shuts off and then coasts to bring
the Timing Gear back to the position shown in of Figure 1-24A.
Another cam on the back of the Timing Gear actuates the Pick Slide which does
two things. First, it engages the dark slide in the film pack and pulls it forward
into the Motor-driven Rollers. The Rollers eject it from the Camera. Second, a
hook on the left end of the Pick engages one of the ratchet teeth on the Counter.
It indexes the Counter from blank to "10" (Figure 1-25).
COUNTER
PICK INDEXES
COUNTER
Figure 1-25. Pick Slide Ejecting Dark Slide and Indexing Counter
As the Counter Wheel indexes, a pin which holds S9 closed moves away from the
Wireform Switch (Figure 1-26). (Note that this occurs while EOC/S9 is still
closed). As a result, the Switch opens and stays open for the remainder of the
exposure cycles until the film pack is removed. When the pack is removed, the
Pack Pawl disengages from the Counter Ratchet and spring action brings the
Counter back to its starting condition. In the starting condition, the pin again
holds S9 closed so it will be ready to divert power for the next dark slide cycle.
RETURN SPRING
PICK SLIDE
1 - 25
TIMING GEAR
PULLS PICK