Olympus OM-1 Repair Manual page 33

B-12
4. When (8547) is rotated, A pin of the (8547) pushes B pin of the (8548),
thus moving the second curtain in the arrowed direction. ((8447) and
(8548) will move simultaneously.)
5. Upon completion of winding as shown below, CA8592 is engaged onto
the tooth of (8547) and locks (8547) and (8548). The first and second
curtains will remain wound up while pooling the returning force towards
the spring. This will complete the charging action of the shutter.
Curtains are wound up
towards this side.
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