Development and Research on Injection Molding Plastic Gear with Positive Utilization of Injection Deformed Layer

注射成型塑料齿轮在齿轮强度或寿命方面需要是一个薄的变形层。然而，对低噪声齿轮的需求越来越大，因此需要开发免维护齿轮。利用在这种背景下注塑齿轮上产生的正变形层的建议，有助于提高注塑齿轮的静音性能。本研究考察了在各种成型条件下制造的齿轮的噪声和磨损特性，以考虑它作为开发一种具有良好静音性能的塑料齿轮的辅助工具。选择聚缩醛共聚物和均聚树脂作为齿轮材料，在不同的成型条件下制备了注射成型塑料齿轮。为了弄清这些齿轮的噪声，利用功率吸收式齿轮试验机进行了实验。通过一系列实验表明，变形层厚度越薄的齿轮噪声级越高，且变形层厚度对齿轮噪声级的影响是可以接受的，并且通过齿轮运行时所受载荷的大小可以看出，变形层厚度对齿轮噪声级和磨损量的影响随硬度的不同而变化。此外，在高负荷情况下，在运行初期出现的积分倍数啮合频率峰值从该频率偏移。从显微照片上可以看出，牙齿轮廓在这些地方明显地塌陷了。因此，它被认为是可取的应用一个变形层作为使用齿轮积极使用的旋转传递，施加负载不需要，以提高低噪音。由此获得了对注塑成型塑料齿轮噪声的影响的宝贵数据。

The injection molding plastic gear needs to be a thin deformed layer in respect of gear intensity or it's life. However, the demand to low noise gear increases and development of the maintenance free gear is desired. The proposal of using positive deformed layer produced on an injection molding plastic gear from such a background is useful to the silence of an injection molding plastic gear. This research examined the noise and the wear characteristic of the gear made under various molding conditions in order to consider it as an aid of development of a plastic gear which was excellent in silence using a deformed layer positively. Two kinds of resin, polyacetal co-polymer and homo-polymer, were chosen as gear material, and the injection molding plastic gears were manufactured under various molding conditions. In order to clarify noise of these gears, the experiment by using a power absorption type gear testing machine was performed. By a series of experiments, the gear with thinner deformed layer thickness had the higher noise level, and the influence of the thickness of a deformed layer was accepted, and it was shown by the size of the load given to the gear in operation that the influence on a noise level and the amount of wear changed with differences of the hardness. Moreover, in the case of high load, the peak of the engagement frequency of the integral multiple which had appeared in early stages of operation shifted from those frequency. It was admitted from the microphotograph that the tooth profile had collapsed remarkably about these. Therefore, it is thought desirable to apply a deformed layer as a use of the gear used positively to the rotation transfer which applied load does not require in order to improve low noise. The precious data for contributing to the silence of an injection molding plastic gear by the above were able to be obtained.