The mechanism converts oscillating motion of segment gear 1, turning about fixed axis A, into reversing rotation of gear 4 at two speeds, one in each direction. The direction and speed of rotation of gear 4 change when segment gear 1 reverses. When segment gear 1 turns clockwise, roll 8 at the end of arm 7 moves along the inner concentric groove c-c of segment gear 1. During this stroke, the rotation of gear 3, meshing with segment gear 1, is transmitted to driven gear 4 through gear 12 which is rigidly attached to gear 3. Near the end of this stroke, dog 5 runs against lug a of arm 7, which turns counterclockwise about fixed axis B, taking gear 3 out of engagement with segment gear 1 and bringing gear 2 into engagement with the segment gear. At this instant, segment gear 1 reverses its oscillation. When segment gear 1 turns counterclockwise, roll 8 at the end of arm 7 moves along the outer concentric groove b-b and latch 9 prevents the roll from dropping back to the inner groove. During this reverse stroke, the rotation of gear 2 is transmitted to driven gear 4 through gear 11 which is rigidly attached to gear 2. Near the end of the reverse stroke, dog 6 runs against lug a of arm 7 which turns clockwise, taking gear 2 out of engagement with segment gear 1 and bringing gear 3 into engagement. At this instant, segment gear 1 reverses again and roll 8 passes to inner groove c-c, with latch 10 preventing it from returning to groove b-b. Because of the difference in the diameters and numbers of teeth of gears 2 and 3, driven gear 4 rotates at two different speeds (one in each direction) which change when segment gear 1 reverses.
$2450$LrG,ML$