发动机曲轴毕业论文

成都工业学院

毕业设计（论文）

设计（论文）题目：发动机曲轴工艺设计及钻中心孔夹具和

钻斜油孔夹具设计

系部名称：机电工程系

专业：数控技术专业

班级：09423

学生姓名：

学号：

指导教师：

二O一二年五月

摘要

曲轴是发动机上的一个重要的旋转机件，装上连杆后，可承接活塞的上下(往复)运动变成循环运动。曲轴主要有两个重要加工部位：主轴颈和连杆颈。主轴颈被安装在缸体上，连杆颈与连杆大头孔连接，连杆小头孔与汽缸活塞连接，是一个典型的曲柄滑块机构。发动机工作过程就是：活塞经过混合压缩气的燃爆，推动活塞做直线运动，并通过连杆将力传给曲轴，由曲轴将直线运动转变为旋转运动。而曲轴加工的好坏将直接影响着发动机整体性能的表现。曲轴的材料一般为35、40、45钢或球墨铸铁QT600-2，曲轴有两个重要部位：主轴颈，连杆颈。本次采用45钢，设计的主要就是这两方面的在数控机床的加工。集合多种的曲轴加工后，深入分析了曲轴的加工工艺。

关键词：曲轴主轴劲夹具连杆劲数控加工

Abstract

The crankshaft is an important engine rotating parts, fitted with linking, you can undertake up and down the piston (reciprocating) motion into circular motion. The crankshaft main two important processing areas: the main journal and rod neck. Spindle neck to be installed on the cylinder block, connecting rod journal and connecting rod hole connection, connect the connecting rod small end hole and the cylinder piston, is a typical slider-crank mechanism. Engine working process: the piston after the blasting of the mixed compressed gas pushes the piston linear motion and force to the crankshaft through the connecting rod, the linear motion into rotary motion by the crankshaft. The crankshaft processing will directly affect the overall performance of the engine performance. The material of the crankshaft is made of carbon structural steel or ductile iron, there are two important areas: the main journal rod neck. This paper introduces the fixture design of the engine crankshaft process design of the two processes. Ensure product quality, increase productivity, reduce costs, make full use of the existing production conditions to ensure workers have designed under the premise of a good and safe working conditions. In process design, the author combines practical theory of design, traditional crankshaft production process improvements, optimizing processes and process equipment, production and processing more economical and reasonable so that the crankshaft. Fixture design part of the collection of processing machine tools, cutting tools and auxiliary tools and other relevant information used based on the workpiece material, structural features, technical requirements and process analysis, in accordance with the fixture design steps to design a line with the crankshaft production process and fixture manufacturing requirements of the fixture.

目录

摘要........................................................................................................................................... I Abstract ............................................................................................................................................ II 目录..................................................................................................................................................... 第1章绪论.. (1)

1.1 课题研究的意义及现状 (1)

1.2 论文主要研究内容 (2)

第2章发动机曲轴零件图分析 (3)

2.1曲轴的作用分析 (3)

2.2曲轴的结构及其特点 (3)

2.3曲轴的主要技术要求分析 (4)

2.4曲轴的材料和毛坯的确定 (4)

第3章工艺规程设计 (5)

3.1 计算生产纲领，确定生产类型 (5)

3.2 选择毛坯 (5)

3.3 工艺过程设计 (5)

3.3.1定位基准的选择 (5)

3.3.2加工阶段的划分与工序顺序的安排 (6)

3.3.3制定工艺路线 (7)

3.4 确定加工余量 (10)

3.4．1确定机械加工余量 (11)

3.4.2设计毛坯图（一）确定毛坯尺寸公差 (12)

3.5重要工序设计 (15)

3.5.1选择加工设备和工艺装备 (15)

3.6 确定切削用量及基本工时 (17)

3.6.1曲轴主要加工表面的工序安排 (17)

3.6.2确定工时定额 (17)

3.6.3粗磨第一主轴颈和齿轮轴颈 (19)

3.6.4精车二、三、五、主轴颈、油封轴颈、法兰 (19)

3.6.5切槽 (20)

3.6.6精车第三主轴颈及过渡圆角 (20)

第4章夹具设计 (24)

4.1 机床夹具的分类、基本组成和功用 (24)

4.2发动机曲轴夹具的设计思路 (24)

4.2.1形状复杂 (24)

4.2.2刚性差 (24)

4.2.3技术要求高 (25)

4.3铣曲轴两端面打中心孔夹具 (25)

4.3.1零件的工艺性分析： (25)

4.3.2零件机械加工工艺路线制定： (25)

4.3.3夹具结构方案确定 (27)