How does a transmission work? | gear stage | calculation transmission ratio | speed | torque | power

This video covers the basics of mechanical power transmission. Transmissions are used in things like power drills or bicycles. They are used to control force and speed, or torque and rotational speed. In gear drives, the conversion is done by gears, in belt drives by belts and pulleys, and in chain drives by chains and chain rings. Transmissions do not change the mechanical power, only the ratio of force to speed or torque to rotational speed. This is ultimately a direct consequence of energy conservation. In this video, the formula for calculating power from force and speed or torque and rotational speed is derived. It becomes clear that the force or torque can only ever be increased at the expense of the speed. An important parameter of a gearbox is the transmission ratio, which indicates how much the speed changes in a gearbox. For gear trains or chain drives, this transmission ratio can be determined from the ratio of the number of teeth. For belt drives, the transmission ratio is calculated from the ratio of the diameters of the pulleys. In multi-stage gearboxes, the conversion of speed and torque takes place in several stages. This allows large transmission ratios to be achieved with small gearbox dimensions. The multiplication of the individual ratios of the respective gear stages results in the total gear ratio of the gearbox. If the speed is reduced by a gearbox, thereby increasing the torque, this is referred to as a power ratio. Conversely, if the speed is increased and thus the torque is reduced, this is referred to as speed ratio. Unlike gear or chain drives, the elasticity of the belt must be taken into account in belt drives. Due to its elasticity, the belt stretches and contracts as it rotates around the pulleys. This causes the belt to slip over the pulleys. This results in a loss of speed and therefore a loss of rotational speed. This phenomenon is known as slippage. Finally, in this video we look at the advantages and disadvantages of the different types of transmissions. 00:00 Example of the use of transmissions 01:27 Adjustment of force (torque) and speed 03:13 Chain drives, gear drives, belt drives 03:44 Power in case of translational motion (linear motion) 05:18 Influencing the force and speed with a transmission 06:54 Power in case of rotational motion (rotary motion) 08:12 Comparison of translational and rotational power 08:48 Relationship between power, torque and rotational speed 09:54 Change in speed (derivation of the formula) 11:03 Transmission ratio (gear ratio) 12:08 Change in torque (derivation of the formula) 14:23 Gearbox (transmission) efficiency 15:22 What are gear stages? 17:43 Advantages and disadvantages of multi-stage gearboxes 18:27 Speed ratio | Power ratio 19:48 How does a chain drive work? 20:48 How does a belt drive work? 22:01 Efficiency and slippage of a belt drive 23:58 Speed and power loss due to slippage 24:53 Advantages and disadvantages of gear trains, belt drives and chain drives