【20160416】Undercutting
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Interference can also be avoided by removing the material on the gear tooth between the base circle and dedendum circle. This is the portion of the gear tooth that is not an involute and would interfere with the mating tooth. An undercut gear tooth is shown in Figure 10.11.
5 d% P3 K/ _! K通过切除基圆与齿根圆间的材料也可以做到避免干涉。齿轮的这部分不具有渐开线廓线，会导致配合齿轮的干涉。如图为一掏槽齿轮的齿。
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Undercutting obviously reduces the strength of the gear, thus reducing the power that can be safely transmitted. In addition, it also reduces the length of contact, which reduces the contact ratio and results in rougher and noisier gear action. Therefore, undercutting should be avoided unless the application absolutely requires a compact gear set. In these cases, advanced kinematic and strength analyses and experiments are necessary to verify proper operation.* V( L3 g, w+ ^" j# z$ E2 e }) ^
显然，掏槽降低了齿轮的强度，因此力可以平缓传递。（齿轮传递力需要高韧性，否则很脆，强度降低可以理解为韧性提高）同时这也减少了接触的长度，使得接触比降低，配合会产生更大噪音。因此，应尽量避免使用掏槽，除非必须要用到紧凑的齿轮组。这时需要更高级的运动分析和实验拟合。. I2 o$ X2 x3 D& _7 M7 W2 T
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楼主: 黑森林的鹿
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发表于 2016-4-16 23:40:59
