一、判断题(对的打√,错的打×) 1.高速钢刀具切削速度一般应小于30m/s。() 2.车螺纹时,由于走刀的影响,使车刀工作前角和后角发生变化。() 3.产生皮带打滑的内因是皮带与带轮间的擦摩力不足。() 4.要使机构具有确定运动,必须使机构原动件数等于机构的自由度数。() 5.渐开线齿轮正确啮合的条件就是模数相等。() 6.车刀主偏角大,切削时径向分力也大。() 7.3Cr2W8与30CrMnSi的含碳量相似,它们都是工具钢。() First, the judgment (for the fight √, wrong × ×) 1. High-speed steel cutting tool cutting speed should generally be less than 30m / s. () 2. Car thread, due to the impact of the knife, so that lathe work before the angle and the angle change. () 3. The internal cause of the belt slippage is that the friction between the belt and the pulley is insufficient. () 4. For the organization to exercise certainty, the number of mover motions must be equal to the agency’s degree of freedom. () 5. Involute gear meshing conditions is the same modulus. () 6. Turning angle of the main tool, the cutting radial component is also large. () 7.3Cr2W8 and 30CrMnSi carbon content is similar, they are tool steel. ()