The main differences between straight bevel gear and spiral bevel gear are as follows

1.Because of the manufacturing error, the instantaneous speed of the straight tooth transmission changes, which is mainly caused by the uneven change of the speed caused by the manufacturing error at the moment when the teeth are meshed in and out, resulting in the polygon effect

2.However, the teeth of spiral bevel gears are in the state of meshing in and out at every moment, and there is no blind area of meshing, so as to ensure the uniformity of speed. It seems that the operation is very stable.

3.The effect of straight bevel gear and spiral bevel gear in operation is the same as that described above, with the following differences:

4.Straight bevel gear is a transmission with two parallel shafts

5.Spiral bevel gear is a transmission with two shafts intersecting

6.When the pitch circle diameter is not changed, the torque on the shaft will not change.

7.The part to be changed is that the force analysis of the gear teeth changes:

8.The normal of the teeth of the straight bevel gear coincides with the moving tangential direction

9.The angle β between the tooth normal and the moving tangent of the spiral bevel gear is always the same,

10.Tooth torque = product of cos β and torque

That is to say: the bending strength of spiral bevel gear is greater than that of straight bevel gear, but the transmitted torque has not changed.

It can also be said that the efficiency is higher, because the tooth strength of spiral bevel gear is higher than that of straight bevel gear, so the external load can be increased, or the rotating speed can be increased to do work. In appearance, the efficiency is higher.

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