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Mechanisms II. Rotary. Pulley Systems. Pulley Systems use a belt to transmit motion and force from the driver shaft to the driven shaft. Speed changes. Speed changes are made by using different size pulleys on the driver and driven shafts.
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Rotary. Pulley Systems. Pulley Systems use a belt to transmit motion and force from the driver shaft to the driven shaft.
Speed changes Speed changes are made by using different size pulleys on the driver and driven shafts. By comparing the size of the two pulleys you can calculate the velocity ratio of the system
n2 n1 d2 d1 1 2 Calculation Pulleys formula: n1 . d1 = n2 . d2 n1: pulley 1 speed d1: pulley 1 diameter n2: pulley 2 speed d2: pulley 2 diameter
Gears Gears are toothed wheels, fixed to the driver and driven shafts, which mesh together. The gears have a whole number of teeth. Gear train
Speed changes Speed changes are made by using different number of teeth on the driver and driven shafts. You can calculate the velocity ratio of the system
Calculation Gears formula: n1.Z1 = n2.Z2 n1: gear 1 speed Z1: gear 1 teeth n2: gear 2 speed Z2: gear 2 teeth
Chain and Sprocket systems Chain and sprocket systems use a chain to transmit rotary motion from the driver to the driven shaft. Sprocket is the name of the gear when it use a chain. The mechanism of the bicycle is a typical example
Chain and Sprocket systems You can use the formula of the gears for this mechanism. It's the same. n1.Z1 = n2.Z2 n1: sprocket 1 speed Z1: sprocket 1 teeth n2: sprocket 2 speed Z2: sprocket 2 teeth
Worm gear Another way of making large speed reductions is to use a worm gear.You can think of the worm as if it were a gear with 1 tooth.
Worm gear. Watch out You can use the formula of the gears for this mechanism. It's the same. n1.1 = n2.Z2 n1: screw 1 speed n2: gear 2 speed Z2: gear 2 teeth
Rack and Pinion Systems. Rack and pinion systems involve changes between rotary and linear motion.