摘 要
曲轴是内燃机的核心部件之一，因此对于加工工艺要求较高。本论文设计的曲轴加工面较多，精度要求也比较高。尤其是连杆以及主轴部分尺寸精度，位置精度以及表面粗糙度要求相当高，所以先采用两顶尖定位，加工主轴部分，再以主轴部分定位来加工连杆，这样能有效的保证所需精度。同时在完成车削、铣削后对加工表面进行磨削，来达到要求的尺寸公差和表面粗糙度。工艺设计的内容包括工艺规程制定中遇到问题的分析、加工余量、切削用量的计算等。在加工连杆以及钻45度斜油孔时，使用普通机床是无法进行加工的，需要设计专用夹具。加工连杆时以主轴定位，工件中心线存在偏心问题，本文采用车床偏心夹具将工件的中心线设定到连杆中心线位置，这样就可以使用普通车床进行加工。钻45度斜油孔时，油孔位置并不是垂直于钻头，本文利用定位元件之间的位置关系，使工件在装夹完成的同时油孔位置垂直于钻头，便可以使用普通钻床进行钻削。夹具设计的内容包括定位、夹紧及误差的计算分析、夹具的校核等。
关键字：曲轴，加工，工艺，夹具
ABSTRACT
The craft is one of the core parts of the diesel engine, In this thesis, the crankshaft machining surface more precision is relatively high. Particular link and the spindle part of the dimensional accuracy, position accuracy and surface roughness very demanding, so the first two-top position, rotating spindle part, then part of the spindle positioning process link, this can guarantee the required accuracy. At the same time the completion of turning, milling, grinding the surface after processing, to meet the requirements of dimensional tolerances and surface roughness. Process design includes process planning analysis of the problems encountered in the development, machining allowance, cutting the amount of calculation. In the processing link, and 45 degree oblique hole drilling, the use of general machine tools can not be processed, the need to design special fixtures. When connecting rod to spindle positioning process, the workpiece center line there is eccentricity, eccentric lathe fixture this paper will be set to link the center line of the workpiece center line position, so that you can use the lathe for processing. 45 degree oblique drill hole, the hole location is not perpendicular to the drill, this paper, the position relationship between the positioning device so that the completed workpiece clamping position perpendicular to the drill hole at the same time, you can use ordinary drilling machine for drilling . Fixture design include positioning, clamping and calculation errors, such as checking fixtures.
Key words: cr
