Yancheng XINLAN Precision Machinery Co., Ltd.

Generally speaking, when many manufacturers produce transmission gearboxes, the transmission gearboxes have sound, but as long as the transmission gearbox can be used without exceeding a certain index, how will the sound of the transmission gearbox be affected? ?

XNUMX. The influence of the type of gearbox on noise:

Different types of gears have different meshing processes due to their different geometric characteristics.

For example, under the same load and speed, the noise of helical gears can be comparedSpur gear3 ~ 10db lower;

XNUMX. The influence of pressure angle on gear noise:

In order to transmit a certain amount of power, f must be kept at a constant value.If the pressure angle a increases, the normal force Fn of the tooth surface will increase, which will increase the pitch impulse and meshing impulse on the actual tooth surface, resulting in friction, resulting in increased vibration and noise levels.

Although the gear center distance error does not affect the precise meshing of the involute tooth profile, its change will cause the periodic change of the working pressure angle.

For example, when the gear is eccentric on the shaft, the rotation frequency of the gear will change, thereby changing its center distance, which will inevitably modulate the frequency of vibration and noise of the gear transmission. The amplitude of the modulation depends on the eccentricity.

XNUMX. The impact of coincidence on gear noise:

The number of gear teeth varies to varying degrees when transferring loads.In this way, the meshing impulse along the meshing line will be generated at the moment of entering and disengaging, thereby generating torsional vibration and noise.

If the instantaneous average number of teeth increases, that is, the coincidence degree increases, the load can be distributed on more teeth, thereby reducing the unit pressure on the tooth surface, thereby reducing the deformation of the gear teeth, improving the impact during meshing and disengagement, thereby reducing Torsional vibration and noise of pinion transmission.

当符合度从1.19增加到2.07时，噪声在1000转/分时降低4dB，在2000转/分时降低6dB。

For helical gears, the degree of coincidence can be increased by changing the helix angle and tooth width B, which can greatly exceed the spur gear, but the helix angle cannot be too large, otherwise it will cause axial vibration.Increasing the number of teeth, increasing the addendum height coefficient or reducing the pressure angle can increase overlap and reduce vibration and noise.