通过查阅资料和相关图册,设计出了满足数控车床需要的横向进给系统以及纵向进给系统;分析其工作原理及结构布置。
摘要:数控车床的进给传动机构,从结构上看是一个由伺服电机提供动力,分X向系统和Y向系统两个机构分别进行横向和纵向的进给。该传动机构一般情况下由伺服电机、导轨支架和导轨副、滚珠丝杠螺母副及其固定装置、工作台等组成。其中伺服电机作为执行元件为整个系统提供动力,驱动滚柱丝杠,滚珠丝杆副将圆周运动转化为直线运动,通过连接块带动上一层的工作平台在导轨上进行直线运动。由于滚珠丝杠螺母副、联轴器、直线导轨副和伺服电机等一些部件有标准件,由专门厂家生产,在设计时只需要根据实际要求进行选型计算,按计算结果选取适当型号即可。此外需注意在设计时要保证进给传动系统的工作精度和稳定性。
本次设计从确定数控机床的大致结构和总体方案入手,对伺服电机、滚珠丝杠副、导轨副、联轴器等部件进行工作载荷计算,进行进给传动机构的主要零件图、部件图和总装配图设计。
关键词:数控车床;进给传动机构;滚珠丝杠副;直线导轨
Design of CNC Lathe Feed Drive Mechanism
Abstract:The feed transmission mechanism of the CNC lathe is, from the structural point of view, powered by a servo motor. The X-direction system and the Y-direction system are respectively fed horizontally and vertically. The transmission mechanism is generally composed of a servo motor, a guide rail bracket and a guide rail set, a ball screw nut set and its fixing device, and a work bench. The servo motor acts as an actuator to power the entire system, driving the roller screw, and the ball screw pair converts the circular motion into a linear motion. The connecting block drives the upper layer working platform to perform linear motion on the guide rail. As the ball screw nut couple, coupling, linear guide pair and servo motor and some other components have standard parts, produced by specialized manufacturers, in the design only need to be calculated according to actual requirements, according to the calculation results to select the suitable model. In addition, care must be taken when designing to ensure the accuracy and stability of the feed drive system.
This design starts with the determination of the general structure and overall scheme of the CNC machine tool, and calculates the working load of the servo motor, ball screw pair, guide rail pair, coupling and other components, and carries out the main parts drawing, component drawing , the feed transmission mechanism and general assembly drawing.
Key words:CNC lathe; feed transmission mechanism; ball screw pair; linear guide
目录
1 绪论 5
1.1 序言 5
1.2 设计主要任务 6
2 进给系统设计 7
2.1 总方案设计 7
2.1.1 概述 7
2.1.2 机械系统设计 7
3 伺服电机设计 9
3.1 伺服电机概述 9
3.2 伺服电机选择原则 10
3.3 伺服电机设计计算 10
3.4 伺服电机选择 11
4 滚珠丝杠副设计 13
4.1 滚珠丝杠副概述 13
4.2 滚珠丝杠副结构 14
4.3 滚柱丝杠副计算设计 14
4.3.1 确定滚珠丝杠副的导程 14
4.3.2 滚珠丝杠副的载荷及转速计算 15
4.3.3 滚珠丝杠副预期额定动载荷 15
4.3.4 估算滚柱丝杠的最大允许轴向变量 16
4.3.5 导程精度的选择 16
4.3.6 确定滚珠丝杠副规格代号 16
4.4 滚珠丝杠副预紧 18
4.5 滚珠丝杠副校核 19
4.5.1 稳定性校核 19
4.5.2 刚度验算 20
4.5.3 效率验算 21
4.6 滚珠丝杠副润滑与密封 21
5 轴承选择 23
5.1 轴承选型 23
5.2 轴承润滑 24
5.3 轴承配合 24
5.4 轴承支承方式选择 24
6 联轴器设计 25
6.1 联轴器概述 25
6.2 联轴器选型计算 26
6.2.1 确定额定扭矩 26
6.2.2 测算最大许用额定扭矩 26