Worm gear motor is a very common type of gear motor. Its structural characteristics are:
- A large transmission ratio can be obtained, which is more compact than the staggered shaft helical gear mechanism.
- The meshing tooth surfaces of the two wheels are in line contact, and their bearing capacity is much higher than that of the staggered shaft helical gear.
- The worm drive is equivalent to a screw drive, which is a multi-tooth meshing drive, so the drive is stable, the noise is small, and it can be self-locking.
- When the lead angle of the worm is less than the equivalent friction angle between the meshing gear teeth, the mechanism is self-locking and can realize reverse self-locking. That is, the worm can only be driven by the worm, and the worm cannot be driven by the worm. Such as the self-locking worm mechanism used in its heavy machine, its reverse self-locking can play a protective role.
- The transmission efficiency is low and the wear is more serious. When the worm gear is engaged in the transmission, the relative sliding speed between the meshing gear teeth is large, so the friction loss is large and the efficiency is low. On the other hand, the relative sliding speed causes serious wear and heat generation of the tooth surface. In order to dissipate heat and reduce wear, expensive materials and good lubricating devices are often used, so the cost is high and the axial force of the worm is large.
Application of self-locking function of worm gear motor
- In the transmission mode of the reducer, the worm gear transmission has the characteristics that other gear transmissions do not have. The worm can easily turn the worm wheel, but the worm wheel cannot turn the worm. This is because the structure and transmission of worm gears are achieved through friction.
- The self-locking function of the worm gear drive is very useful in mechanical applications. Such as winches, conveying equipment and so on. However, it is also because of the friction transmission mode of the worm gear that the transmission efficiency of the worm gear is much lower than that of the gear transmission.
- Not all DC worm gear motors have a good self-locking function, and the self-locking function of the worm gear can only be achieved if it reaches a certain speed ratio. This is related to the lead angle, that is, the self-locking function of the worm gear with a small speed ratio is not so good.