Ever Power

Worm Wheel

What is a worm gear

Worm gear mechanism is often used to transfer the motion and power between two staggered shafts. Worm gear and worm are equivalent to gear and rack in its middle plane, and worm is similar to screw in shape. The gear reduction ratio of worm gear is generally 20:1, sometimes even as high as 300:1 or more.

Basic Concepts

If you want to get a larger gear reduction ratio, you need to use worm gear. The gear reduction ratio of worm gear is generally 20:1, sometimes even as high as 300:1 or more.Many worm gears have an interesting feature that other gear sets don’t: the worm can turn the gear easily, but the gear can’t. This is because the protruding angle on the screw is very shallow. When the gear tries to rotate the screw, the friction between the gear and the screw will keep the screw in place.

Correct Engagement

1. In the middle plane, the modulus and pressure angle of worm and worm gear are equal respectively, that is, the end modulus of worm gear is equal to the axial modulus of worm and is the standard value; the end pressure angle of worm gear should be equal to the axial pressure angle of worm and is the standard value.

2. When the staggered angle of worm and worm is, it should be ensured, and the spiral direction of worm and worm must be the same.

Tea Subscription

Ever Power Group Co., Ltd. specializes in the production of all kinds of mechanical transmission and hydraulic transmission: planetary gearbox, worm gear reducer, in-line spiral gear reducer, parallel shaft spiral gear reducer, spiral bevel gear reducer, spiral worm gear reducer, agricultural gearbox, tractor gearbox, automobile gearbox, power output shaft, special reducer and related gear parts and components Other related products, chain wheel, hydraulic system, vacuum pump, hydraulic coupling, rack and pinion, chain, timing pulley, UDL transmission, V-belt pulley, hydraulic cylinder, gear pump, screw air compressor, low backlash worm reducer, etc. In addition, we can customize transmission, gear motor, motor and other hydraulic products according to customers’ drawings.


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Institutional Features

1. A large transmission ratio can be obtained, which is more compact than the staggered helical gear mechanism

2. The meshing tooth surfaces of the two gears are in line contact, and their bearing capacity is much higher than that of the staggered helical gear mechanism

3. Worm drive is equivalent to screw drive, which is multi tooth meshing drive, so the transmission is stable and the noise is very small

4. It is self-locking. When the lead angle of the worm is less than the equivalent friction angle between the meshing teeth, the mechanism has self-locking and can realize reverse self-locking, that is, the worm can only drive the worm wheel, but not the worm wheel. Such as the self-locking worm mechanism used in heavy machinery, its reverse self-locking can play a role of safety protection.

5. The transmission efficiency is low and the wear is serious. When the worm gear is meshed, the relative sliding speed between the meshing teeth is large, so the friction loss is large and the efficiency is low. On the other hand, because of the relative sliding speed, the tooth surface is seriously worn and heated. In order to dissipate heat and reduce wear, expensive materials with good friction reduction and wear resistance and good lubrication devices are often used, so the cost is high.

6. The axial force of worm is large.