Classification of gear couplings

Tooth coupling refers to the internal and external gear teeth meshing to transfer torque. Because the top of the outer teeth of the semi-coupling is processed into a sphere (the center of the sphere should be located on the axis), and there is a large tooth gap between the meshing teeth, so that it has a good ability to compensate the displacement of the two axes in any direction. If the outer gear is modified to form a drum tooth, it is more conducive to increase the ability of the coupling to compensate for the comprehensive displacement.

The gear coupling can be divided into three types according to the different axial gear shape of the outer gear sleeve, namely, the straight gear coupling, the drum gear coupling and the special drum gear coupling. In either case, the inner gear ring and the involute spur inner gear are the same except for the difference in the selection of the top clearance coefficient of the gear teeth.

The axial tooth billet of the outer tooth sleeve of the straight tooth coupling can be processed into straight line and circular arc, and the dividing circle and the root circle are straight lines. The meshing form of this coupling is exactly the same as the meshing form of the inner and outer teeth of the involute cylindrical gear. The relative displacement between the two axes is compensated by increasing the lateral clearance of the inner and outer teeth, but the compensation amount is limited.

The tooth top of the outer tooth sleeve of the drum gear coupling is processed into an arc, that is, the tooth billet is processed into a sphere. In the section of the central plane of the tooth and tangent to the joint cylinder surface, the tooth forms a drum, that is, the so-called drum type coupling.

Its characteristics are:

1. High bearing capacity, calculated by bending strength, under the same conditions, the torque transmitted by the straight gear coupling is increased by 15 ~ 30%;

2. Reasonable structure and reliable performance. Due to the drum shape of the tooth side, the contact situation of the axis is improved under a certain Angle condition, so as to reduce the contact stress and eliminate the load concentration of the tooth end of the straight tooth coupling, which eliminates the edge extrusion and improves the performance.

3, the compensation performance is good, the tooth shape of the outer tooth sleeve is drum shape, increasing the allowable relative offset of the two axes, the maximum allowable inclination Angle can reach 6 degrees, generally recommended 1.5° ~ 2.5°.