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DOUBLE-RATCHET DWELL MECHANISM

Lever 1 oscillates about fixed axis A and carries pawl 2 which engages the teeth of ratchet wheel 3. Wheel 3 is keyed to shaft 7 and rotates it intermittently counterclockwise about axis A. Pawl 4, also pivoted on lever 1, engages the teeth of ratchet wheel 5 which is confined between leather friction disks 6 that can be adjusted to obtain the required pressure. Shield, or mask, a, carried on ratc…