Is the reducer noisy? Find the reasons from gear modification to box design

1. Gear design and modification optimization

The gear is the core transmission component of the reducer, and its design and manufacturing accuracy directly determines the noise level.

Improve gear accuracy: Use high-precision gear grinding technology to strictly control tooth shape errors, tooth pitch errors, etc. Research shows that gears with small errors in tooth shape and tooth surface roughness can produce noise that is more than 10 decibels lower than ordinary gears.

Implement gear tooth modification: Conscious micro-modification of the tooth surface is a key means of reducing noise.

Tooth profile modification: Modifying the tooth top or tooth root can effectively reduce the impact vibration of the gear teeth at the moment of meshing in and out, and reduce the dynamic load.

Tooth direction modification: Improve the distribution of load along the tooth width direction through drum modification or curved surface modification to avoid excessive local stress and increase in noise caused by unbalanced load.

Optimize gear parameters: Improving the overlap of gears (such as using helical gears instead of spur gears), increasing tooth width to improve rigidity, or considering using cast iron or plastic gears with higher damping rates under light load and low speed conditions will all help reduce noise.

2. Box structure and sound insulation design

The cabinet is not only a supporting structure but also a major source of noise radiation.

Enhance the box stiffness: Optimizing the box structure through finite element analysis (FEM) and rationally arranging stiffeners (ribs) can significantly improve the box stiffness and avoid structural resonance near the gear meshing frequency.

Adopt sound insulation structure: The new generation of reducer begins to adopt a double-wall box structure, and the interlayer is filled with sound-absorbing materials such as polyurethane foam. Actual measurements can reduce the noise by 12-15 decibels.

Blocking vibration transmission: Installing a special rubber damping ring on the contact surface between the bearing seat and the box can effectively block the transmission path of vibration to the box.

3. Lubrication system status

Good lubrication is the basis for reducing friction noise and forming an effective oil film.

Choose the right lubricant: Choose the lubricant with appropriate viscosity and quality according to the working conditions (speed, load, temperature). Lubricants with higher viscosity are generally better at reducing noise. For heavy load conditions, it is recommended to use synthetic gear oil with better thermal stability.

Ensure oil quality and quantity: Check and replace lubricating oil regularly to prevent the oil from aging, contamination or containing metal wear debris. Insufficient or excessive oil can lead to increased noise.

Control oil temperature: Excessively high oil temperature will reduce the viscosity of the lubricating oil and weaken the load-bearing capacity of the oil film, resulting in increased friction noise. Ensure that the cooling system is working properly and the oil temperature is maintained in the optimal range (such as 50±5℃).