1. Mechanisms II

2. Rotary. Pulley Systems.
Pulley Systems use a belt to transmit motion and force from the driver shaft to the driven shaft.

3. 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

4. Calculation Pulleys formula: n1 . d1 = n2 . d2 1 2 n1: pulley 1 speed
d1: pulley 1 diameter
n2: pulley 2 speed
d2: pulley 2 diameter d1 d2 1 2 n1 n2

5. 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

6. 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

7. Calculation Gears formula: n1 . Z1 = n2 . Z2 n1: gear 1 speed
Z1: gear 1 teeth
n2: gear 2 speed
Z2: gear 2 teeth

8. 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

9. 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

10. 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.

11. Worm gear. Watch out n1 . 1 = n2 . Z2
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

12. Rack and Pinion Systems.
Rack and pinion systems involve changes between rotary and linear motion.

13. The End