摘要本毕业设计是汽车变速箱箱体的加工工艺及一道工序的夹具设计。我们不仅要加工箱体的平面还要加工箱体的孔系，这是由汽车变速箱箱体零件的结构特点所决定的。根据所学知识，保证孔系的加工精度要比保证平面的加工精度难很多。所以，该设计遵循先面后孔的原则。同时加工过程也分化为粗加工和精加工两个阶段从而保证孔系的加工精度。粗基准选择变速箱箱体的输出输入轴的支承孔，精基准选择两个工艺孔和顶面。对于主要加工工序的安排，首先加工顶面用及支承孔系来定位，然后加工工艺孔，用支承孔和顶面定位。除了个别的工序，在后续加工工序中，均采用工艺孔和顶面定位加工平面和孔系。加工支承孔系采用坐标镗孔法。在整个加工过程中都采用组合机床，同时选用专用夹具，对于夹紧方式，由于需要大批量生产，在流水线上进行加工。为了提高生产效率，采用气动夹紧方式。61604

毕业论文关键词: 箱体  加工工艺  工序  专用夹具

毕业设计说明书（论文）外文摘要

Title         Automotive transmission housing and fixture design process

Abstract The graduation project is a car gearbox casing processing technology and a process of fixture design. By the automobile gearbox housing parts of the structure and pore characteristics determine system is the flat part of the main processing surfaces. According to the knowledge, ensure Holes machining precision machining precision than the guaranteed plane much more difficult. Therefore, the design follows the principles of the hole after the first plane. Meanwhile, in order to ensure precision machining holes of, the process is differentiated for the roughing and finishing of two phases. Select the transmission housing benchmark crude output of the input shaft bearing hole, fine craft benchmark select two holes and the top surface. Arrangements for the main processing steps, first working with the top surface and the support system to locate the hole, and then processing hole, with the top surface of the bearing hole and positioning. In addition to the inpidual processes in the subsequent processing steps, have adopted technological holes and the top surface and the hole machining plane positioning system. Processing system using coordinate support hole boring laws. In the whole process are used in combination machine, and use special fixtures for clamping, the need for mass production, the assembly line for processing. In order to improve production efficiency, the use of pneumatic clamping.

Keywords: Gearbox  machining-technology  step  special-purpose clamping apparatus

1  引言 1

1．1  课题背景 1

1.1.1  制造业的重要性 1

1.1.2  变速箱的原理及功能 1

1.1.3  变速箱的工艺设计的重要性 1

1．2  课题目的 1

1.2.1  毕业设计的目的及作用 1

2  汽车变速箱箱体加工工艺规程设计 2

2．1  箱体的分析 2

2.1.1  箱体的作用 2

2.1.2  箱体的工艺分析 2

2. 2  毛坯的分析 3

2.2.1  毛坯的了解 3

2.2.2  毛坯的制造 3

2.2.3  毛坯的确定