Weight 1, moving downward by gravity, is hung from pulley 2. Endless chain 3 runs over pulleys 2, 4, 5 and 6 and chain sprockets 7 and 8. Hung from pulley 6 is weight 10 which tensions the lowered portion of chain 3 when weight 1 is raised. Chain sprocket 8 rotates about axis 11 and is rigidly attached to ratchet wheel 9. Pawl a prevents counterclockwise rotation of ratchet wheel 9. Freely mounted on axis 11 is winding lever 12 whose pawl b engages ratchet wheel 9. Rigidly attached to lever 12 is chain sprocket 13 over which chain 14 runs. One end of chain 14 is attached to spring 15 and the other to pedal 16. When weight 1 nears its lower position, pedal 16 is depressed and chain 14 turns sprocket 13, lever 12, pawl b, ratchet wheel 9 and sprocket 8 clockwise, raising weight 1. Spring 15 returns the mechanism to the position shown. The mechanism applies a constant counterclockwise torque to the shaft on which sprocket 7 is keyed.
$1898$FL,ML$