There are many factors to consider when designing nylon wheels. On the one hand, we must consider the application force of the material, but also consider its deformation factors: let's introduce it in detail below.
When plastic gears and metal gears are matched, heat dissipation and other performances are ideal. When running all plastic gear systems, it is recommended to use different materials (such as nylon and phenolic plastic). Due to frictional heat and changes in environmental conditions, the thermal expansion coefficient of plastic is much higher than that of metal. Plastic gears need sufficient backlash. It is recommended that the backlash be calculated by the following formula:
When the number of teeth is less than 35, the backlash = (0.06～0.1) P (modulus)
When the number of teeth is 35 or more, the backlash is calculated according to the experimental formula proposed by HACHMAN.
The entire tooth root is rounded and the pressure angle of the gear is 200, the yield strength of the gear is greater than that of the 14.50 pressure angle gear
Improved, its load capacity is increased by 15% compared with the latter, or its service life can be extended by 3.5 times under the same conditions.
Under the condition of satisfying the load, consider choosing the small tooth design, so that the tooth heat generated by high-speed operation is less.
In order to make the gears have higher torque, you can consider casting machined steel parts directly into the gears.
Under the provided environmental factors such as temperature, humidity and chemical conditions, MC nylon wheels are usually better than other engineering
plastic. The choice of material depends on both the environment and the operating conditions.
The operating temperature limit of MC nylon is about 120℃. When the temperature rise caused by frictional heat exceeds this limit, the gear will not work normally; if the load is constant, the frictional heat will increase with the increase of the gear speed, even under extreme conditions. Causes the surface of the teeth to melt. Therefore, we suggest that the maximum linear speed of MC nylon wheels should be limited to 25 m/s.
