Under the same conditions, the noise of spur gear transmission is usually greater than that of helical gears. The reasons are as follows:
1. * * meshing method * *: The tooth surface of a spur gear is in instantaneous contact during meshing, and the impact force between the tooth surfaces is relatively large, which is prone to producing significant noise. The tooth surface meshing of helical gears is gradually in contact, the contact surface gradually increases, the meshing process is relatively smooth, and the noise is relatively low.
2. * * Load Distribution * *: Due to the inclined tooth surface of helical gears, the load distribution on the tooth surface during meshing is more uniform, which can reduce local pressure and impact, thereby reducing noise.
3. * * Vibration *: Due to the instantaneous meshing of spur gears, it is easy to cause significant vibration. The progressive meshing method of helical gears can effectively reduce vibration, thereby reducing noise.
Therefore, under the same working conditions, the transmission noise of helical gears is usually lower than that of spur gears.