齿轮在啮合时,相啮合的轮齿非工作齿面间要留有侧隙。在一对相啮合的齿轮中,当其工作齿面正在节园附近接触时,与此工作齿面邻近的两非工作齿面之间的最短距离,称为法向侧隙。在端截面上量度两非工作齿面所得到的节园园周方向的距离,称为端面侧隙。 When the gear is engaged, there should be a backlash between the non-working tooth surfaces of the meshing gear teeth. In a pair of intermeshing gears, the shortest distance between two nonworking tooth flanks adjacent to this working tooth face is called the normal backlash when its working tooth face is contacting near the knuckle. Measure the distance between two non-working flanks on the end section in the circumferential direction of the garden, which is called as the backlash.