凸轮机构换刀机械手结构设计

摘  要

当代机械制造业的快速发展带动了对加工中心自动换刀装置的研究，自动换刀装置正朝着快速化、小型化方向发展。通过对凸轮式自动换刀装置中的凸轮机构进行研究，将弧面凸轮和平面沟槽凸轮设计为一体。在实现凸轮机构高速运行的同时，使其体积更小、重量更轻。

本文研究的凸轮机构，即凸轮式ATC的核心部件，它由弧面凸轮和平面沟槽凸轮组成，其中弧面凸轮实现换刀机械手的旋转运动，平面沟槽凸轮实现机械手的直线往复运动。该凸轮机构的特点是将弧面凸轮和平面沟槽凸轮设计为一体，即在弧面凸轮的端面上加工出平面沟槽凸轮。此结构的整体优点是布局紧凑，重量轻，换刀时间短,工作可靠性高。

加工中心采用凸轮换刀机构可以有效地提高换刀速度和可靠性。水平转动的机械手采用蜗杆凸轮间歇运动机构,该机构利用空间凸轮和转位拨销的作用,将凸轮主动件的连续转动转换成转盘)的间隙运动。凸轮的表面呈凹形曲面轮廓,上有一条突脊宛如圆弧面蜗杆。圆柱形拨销均匀分布在从动转盘的外周,呈幅射状,犹如蜗轮的齿。

关键词：凸轮机构；换刀机械手；结构设计；CAD设计

Abstract

The rapid development of the modern machinery manufacturing industry has led to the research on the automatic tool changing device in the machining center. By studying the cam mechanism in the cam-type automatic tool changer, the arc cam and plane groove cam are designed as one. while realizing the high speed operation of the cam mechanism, it makes it smaller in size and lighter in weight.

cam mechanism studied in this paper, i.e., the core component of cam type ATC, is composed of arc surface cam and plane groove cam, in which the arc surface cam realizes the rotating motion of the tool changing manipulator, and the plane groove cam realizes the linear reciprocating motion of the manipulator. The characteristic of the cam mechanism is that the arc cam and the plane groove cam are designed as one, that is, the plane groove cam is machined on the end face of the arc surface cam. The overall advantages of this structure are compact layout, light weight, short tool changing time and high working reliability.

Using cam tool changing mechanism in machining center can effectively improve the speed and reliability of tool changing. The manipulator with horizontal rotation adopts the intermittent motion mechanism of worm cam, which converts the continuous rotation of cam active parts into a rotary disc by using the function of space cam and transposition dial pin. The surface of the cam is concave curved surface contour, there is a ridge like arc surface worm. The cylindrical pins are evenly distributed in the periphery of the driven turntable, which is shaped like a worm gear tooth.

Keywords: cam mechanism; tool changer manipulator; structure design; CAD design

目录

凸轮机构换刀机械手结构设计- 1 -

摘  要- 1 -

Abstract- 2 -

1   换刀机械手的相关介绍- 4 -

1.1数控技术的发展历程- 4 -

1.2数控加工中心的基本功能- 4 -

1.3加工中心的组成部分- 5 -

1.3.1 刀库- 5 -

1.3.2 刀具交换装置(机械手)- 5 -

1.3.3 运刀装置- 6 -

1.3.4 刀具编码装置- 6 -

1.3.5刀具识别装置- 7 -

1.4刀库的驱动及定位- 7 -

1.5我国数控系统的发展概况- 8 -

1.6数控系统的发展趋势- 9 -

2换刀机械手的总体方案设计- 9 -

2.1设计任务- 9 -

2.2机械手的平稳性- 9 -

1、影响平稳性以定位精度的因素- 9 -

（1）、惯性力的影响- 9 -

（2）、结构刚度的影响- 10 -

（3）、定位方法的影响- 10 -

（4）、控制系统的影响- 10 -

（5）、驱动源的影响- 10 -

2 机械手的运动特性- 10 -

2.3机械手运动特性的分类- 11 -

2.4开关型机械手的速度及位置控制- 12 -

一、 液压机械手的速度控制- 12 -

二、 气动机械手的速度控制- 12 -

三、 开关型机械手的定位系统- 12 -

1、 电气开关定位- 12 -

2、机械挡块定位- 12 -

2.5机械传动型机械手速度及位置控制- 13 -

2.6 机械手类型确定- 13 -

2.7 驱动系统和电控系统的选择- 13 -

1— 驱动电动机 2—减速器 3—锥齿轮 4—平面凸轮- 24 -

5—弧面凸轮 6—连杆机构 7—机械手 8—滚动盘 9—电气信号盘- 24 -

4换刀机械手的参数和计算- 28 -

4.1手臂的弯曲变形- 28 -

4.2 电动机的选择- 31 -

致谢- 37 -

参考文献- 38 -