Speed reducers are generally used in low-speed, high-torque transmission equipment . They reduce the speed of electric motors, internal combustion engines, or other high-speed power sources by meshing a smaller gear on the input shaft with a larger gear on the output shaft . Ordinary speed reducers may also have several pairs of gears operating on the same principle to achieve the desired speed reduction. The ratio of the number of teeth on the large gear to the number of teeth on the small gear is called the transmission ratio. A speed reducer is a power transmission mechanism that uses a gear speed converter to reduce the rotational speed of a motor to the desired speed and obtain a larger torque.
- Function of a speed reducer
1) While reducing speed, increase output torque. The torque output ratio is calculated by multiplying the motor output by the reduction ratio, but care must be taken not to exceed the rated torque of the reducer.
2) Speed reduction also reduces the load's inertia; the reduction in inertia is equal to the square of the reduction ratio. You can see that most motors have an inertia value.
Types of speed reducers
Common speed reducers include helical gear reducers (including parallel shaft helical gear reducers, worm gear reducers, bevel gear reducers, etc.), planetary gear reducers, cycloidal pinwheel reducers, worm gear reducers, planetary friction mechanical continuously variable transmissions, etc.
- Common types of speed reducers
1) The main characteristics of worm gear reducers are that they have a reverse self-locking function, can have a large reduction ratio, and the input and output shafts are not on the same axis or in the same plane. However, they are generally large in size, have low transmission efficiency, and low precision.
2) Harmonic reducers utilize the controllable elastic deformation of flexible elements to transmit motion and power. They are compact and highly precise, but their disadvantages include limited flexspline life, poor impact resistance, and lower rigidity compared to metal components. The input speed cannot be too high.
3) Planetary gearboxes have the advantages of compact structure, small backlash, high precision, long service life, and the ability to achieve a large rated output torque. However, they are slightly more expensive.
