摘 要

汽车变速器拨叉摇臂是拨叉的组成部分，拨叉摇臂形状复杂，受力大，需要用锻造（挤压）工艺成形，生产批量为7.0万件/年，材料为Q235。拨叉摇臂锻件成形精度有一定要求，企业要求采用热模锻工艺成形。本次设计需要完成拨叉摇臂的锻件设计、模锻成形工序、参数计算和热锻模具设计等，并提交开题报告、模具图纸和设计说明书等技术资料。

根据拔叉摇臂的形状及尺寸，本次设计的工序主要有镦粗、压扁、成形、切边、弯曲、整形等工序。主要完成成形部分的模具设计，选用热模锻摩擦压力机，压力机的吨位为20吨。拨叉摇臂的材料为Q235，热锻的温度为1200°。

本次拨叉摇臂设计的特点在于将摇臂拉直成一个带有枝丫的长杆类的零件之后再通过弯曲成形，这样避免了一边锻造一边弯曲的导致锻件中材料无法充满的情况，先锻造后弯曲可以是料更好的充满型腔，而且设计起来也比较简单。

通过设计的方案，可以减少尺寸误差，合理的分布零件的模具布局，增加零件的材料利用率，提高工艺性能，提高锻件的抗拉抗压强度。

关键词：拨叉摇臂；热锻模具；镦粗；成形

Abstract

Auto transmission fork rocker arm is part and parcel of the fork, the fork arm shape is complex, stress is big, need to use forging, extrusion forming process, the production batch to 70000 every year, materials for Q235.Fork radial forging precision forming has certain requirements, enterprises require the use of hot die forging forming process.The design needs to complete the fork of the rocker arm forging design, die forging forming process, parameter calculation and hot forging die design, etc., and submit the opening report, die drawing and design manuals and other technical data.

According to the fork of the rocker shape and size, the design process of main pier rough, flattening, forming, cutting, bending, plastic, etc. Complete forming the main part of the mold design, choose friction screw press, hot die forging press tonnage of 20 tons. Fork of the rocker arm material is Q235, hot forging temperature of 1200 °.

The fork arm design features to rocker arm straight into a long pole with branches class parts and then through the bending forming, thus avoided while forging bend forging materials cannot be full, in bending can be expected after forging first better fills the cavity, and the design is more simple.

Through the design scheme, can reduce the size error, reasonable distribution of components of the mold layout, increase the utilization rate of material parts, improve process performance, improve the tensile compressive strength of forgings.

Key Words：Fork rocker arm；hot-forging die；Pier coarse；forming

目 录

第1章 绪论 1

1.1 设计主要内容 1

1.2 设计目的、意义 1

1.2.1 设计的目的 1

1.2.2 设计的意义 2

第2章金属成形基本理论 3

2.1 金属锻造基本理论 3

2.1.1 变形及应力 3

2.1.2 塑性变形基本定律 3

2.1.3 滑移和孪生 5

2.2 弯曲理论（三向应力） 5

第3章摇臂数模的建立与数值模拟 7

3.1 摇臂Pro/E 3D建模............................................... 7

3.1.1 Pro/E软件简介及基本操作............................................... 7

3.1.2 Pro/E 3D建模.............................................................................. 8

3.2 CAD 2D锻件图............................................................................. 11

3.2.1 CAD/CAM技术............................................................................. 11

3.2.2 CAD 2D锻件图............................................................................. 11

3.3 成形力的计算............................................................................. 13

3.3.1 锻件图的设计............................................................................. 13

3.3.2 计算并确定锻件的基础数据.................................................................... 17

3.3.3 模锻机的选择............................................................................. 17

3.3.4 飞边槽的选择..................................................................... 18

3.3.5 胚料的计算..................................................................... 18

3.4 Deform 3D软件与摇臂成形数值模拟............................................ 19

3.4.1 Deform软件介绍...................................................................................19 3.4.2 摇臂成形数值模拟 ...............................................................................19

第4章摇臂成型模具设计.................................................................................21

4.1 模具总体结构设计.............................................................................................21

4.1.1 锻模总体结构.............................................................................................21

4.1.2 锻模高度尺寸设计....................................................................................21

4.2 摇臂成型设备的选择......................................................................................22

4.3 模架设计..........................................................................................................23

4.3.1 模架结构形式..........................................................................................23

4.3.2 导向装置..................................................................................................24

4.3.3 顶料装置..................................................................................................24

4.4 锻模结构与型腔设计.....................................................................................25

4.4.1镶块设计..................................................................................................25

4.4.2 型腔设计.................................................................................................25

第5章 拨叉摇臂成形工艺与模具设计总结..........................................29

5.1 设计过程介绍..............................................................................................29

5.1.1 设计的基本内容..................................................................................29

5.1.2 设计的工序方案..................................................................................29

5.1.3 进度安排..............................................................................................29

5.2 摇臂成形工艺设计的特点........................................................................29