Description
Duplex Worms Gear
A duplex worm gear is a gearing system that consists of two worm gears mounted on a common shaft. This configuration provides increased load capacity, and improved efficiency, and allows for backlash compensation. By distributing the load between the two gears, a duplex worm gear can handle higher torque transmission while maintaining compactness. It finds applications in various industries where high torque, precise motion control, and space efficiency are required, such as automotive, robotics, and machinery.
On the worm wheel, the various modules produce various addendum modification coefficients, as well as the diameters of the rolling circles on both sides. Due to this, the profiles differ on the front and rear sides. The tooth’s thickness and the gaps between them remain the same across its circumference.
Adjusting backlash is done by moving the worm axially in such a way that the part of the worm that has the required tooth size is within contact with the wheel, providing the backlash you want (fig. 1).
In this way, the backlash can be adjusted easily to any desired amount while placing the gear. Even gears that are worn can be adjusted with care and continuously without altering the tooth contact, or causing meshing interference.
In addition to the duplex method described above there are many options to alter your worm gear’s backlash.
- Variation of the center distance through rotating an eccentric hub where the worm shaft as well as the wheel of the worm gear are held
- The axial shift of the cone-shaped worm (fig. 2a)
- The worm is divided into 2 halves (fig. 2b) which can be rotated or moved to one another. (system Ott)
- The wheel is divided into the form of two discs (fig. 2c) that can be rotated close to one opposite.
