大连理工大学本科毕业设计（论文）

斜齿直齿双联齿轮注塑模具设计

Design of the injection mold for the joint of a spur gear

and a helical gear

学 院（系）： 机械工程学院 专 业： 机械设计制造及其自动化 学 生 姓 名： 尹鑫 学 号： 201061824 指 导 教 师： 祝铁丽 评 阅 教 师： 完 成 日 期： 2015年6月5日

大连理工大学

Dalian University of Technology

斜齿直齿双联齿轮注塑模具设计

摘 要

模具是工业生产的基础工艺装备，被称为“工业之母”。作为国民经济的基础行业，模具涉及机械、汽车、轻工、电子、化工、冶金、建材等各个行业，应用范围十分广泛。其中注射成型模具是最常用的塑料零件成型模具，因此，研究注塑模具对了解塑料产品的生产过程和提高产品质量具有重大意义。

本说明书的设计对象为斜齿直齿双联齿轮注塑模具设计，下文详细介绍了本次设计的全部过程。首先查阅相关书籍了解模具的工作原理以及各部分的组成、功用，然后根据本次毕业设计题目的要求，寻找合适的原型零件。接下来分析零件的特征，经过分型面的选择、确定型腔布置方案、浇注系统的设计、导向和推出机构的确定、冷却系统的设计算以及模架的选择最终完成对斜齿直齿双联齿轮注塑模具的设计。在这部分中，设计重点在于浇注系统的设计和导向推出机构的设计两个方面。首先要根据零件的特性，来决定采用何种浇注方式。然后进行浇注系统系统设计，将分流道进行合理的分布，尽量让热熔融塑料均匀的流动到零件的型腔中。由于斜齿的存在，塑料零件成型后如何顶出，是决定模具能否正常工作的一个关键问题。在老师的建议下，采用镶件和轴承相互配合的方法，来解决零件顶出的问题。接着对模具设计的方法、依据、计算校核进行了阐述，并且对模具主要零件的尺寸进行了分析计算，最后模具设计过程中的经济性进行了分析。

关键词：注塑模具；双联齿轮；浇注系统；顶出机构

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斜齿直齿双联齿轮注塑模具设计

Design of the injection mold for the joint of a spur gear and a

helical gear

Abstract

The mould is the basic technological equipment of industrial production. It is called “the mother of industry.” As the basic industry of the national economy, the mold involves machinery, automobile, light industry, electronics, chemical, metallurgy, building materials and other industries. It covers kinds of field. And injection molding is the most common plastic parts forming mold, therefore, research injection mold for understanding the plastic product production process and improve the product quality is of great significance. The object of this paper is to design the injection mold for Straight- helical duplicate gear，below introduces the design of the whole process in detail. First, this paper introduces the mold industry situation recently, then the duty of this injection mold design and the plastic material characteristics are analyzed. After choosing the parting plane, arrangement of the cavity scheme, design of the runner system, determination of the guiding mechanism, design of the cooling system and choice of the ejection mechanism are carried out. In this part, the key points are the design of the runner system and design of the guide and the ejecting mechanism. First of all, according to the characteristics of the parts, I decide to use what kind of pouring method. Then I design the runner system. Make the runner system reasonably distributed, and the flow of the hot melt plastic can be evenly distributed to the part of the cavity. Because of the existence of helical gear, how make the plastic parts out of the mold, is the key problem that decides whether the mold can work properly. Under the advice of the teacher, I use the bearing to solve the problem of the parts ejection. In addition, strength check, the efficiency for the mold design and dimensional computation of mold parts are also described in detail. Finally, the sizes of some parts are analyzed, as well as the economic analysis of mold design process has bean done.

Key Words：Injection mold；Duplicate gear；Runner system；Ejecting mechanism

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斜齿直齿双联齿轮注塑模具设计

目 录

摘 要 ..................................................................................................................................... I Abstract ..................................................................................................................................... II 引 言 .................................................................................................................................... 1 1 绪论 ...................................................................................................................................... 2

1.1 注塑成型原理及工艺特点 ....................................................................................... 2

1.1.1 注塑成型原理 ................................................................................................ 2 1.1.2 注塑成型特点 ................................................................................................ 2 1.2 注塑模具结构组成 ................................................................................................... 2 2 斜齿直齿双联齿轮塑件分析 .............................................................................................. 4 3 注塑材料POM的性能分析 ............................................................................................... 6

3.1 POM塑料介绍 ......................................................................................................... 6 3.2 POM塑料特点 ......................................................................................................... 6 3.3用途 .............................................................................................................................. 7 4 注塑模具结构设计 .............................................................................................................. 8

4.1 分型面 ....................................................................................................................... 8

4.1.1 选择分型面的原则 ........................................................................................ 8 4.1.2 分型面的选择 ................................................................................................ 9 4.2 型腔布置 ................................................................................................................. 10

4.2.1 影响型腔数目的因素 .................................................................................. 11 4.2.2 型腔布置的原则 .......................................................................................... 11 4.3 浇注系统 ................................................................................................................. 12

4.3.1 主流道的设计 .............................................................................................. 12 4.3.2 分流道的设计 .............................................................................................. 14 4.3.3 浇口设计 ...................................................................................................... 15 4.3.4 冷料穴的设计 .............................................................................................. 15 4.4 导向机构 ................................................................................................................... 16 4.5 推出机构 ................................................................................................................. 17

4.5.1 推出机构的设计原则 .................................................................................. 17 4.5.2 推出机构设计遇到的问题和解决的方案 .................................................... 18 4.5.3 推出机构设计 ................................................................................................ 22 4.6 温度调节系统 ......................................................................................................... 23

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