车床英语最新ppt课件

1、Lesson Fifteen Lathe一、一、new words?lathe leie n. 车床车床?1?headstock hedst?k n.主轴主轴箱，床头箱箱，床头箱?tailstock n. 尾架，尾座尾架，尾座?bed bed n.（机床）床身（机床）床身?tool-post tu:lp?ust n. 刀架，刀架，刀座刀座?cross-slide kr?s-slid n. 横向横向滑板，中拖板滑板，中拖板?sideward saidw?:dz ad. 侧侧面地，向旁边地面地，向旁边地?saddle s?dl n. 大拖板，床大拖板，床鞍鞍?carriage 5kAridV n.

2、（机床）（机床）溜板，拖板溜板，拖板?center sent? n.顶尖顶尖?turret t?rit n.转塔转塔?incorporate ink?:p?reit v. 包括，合并包括，合并?matter m?t? v. 要紧，有重要紧，有重大关系大关系?tapered teip?d a. 锥形的锥形的?nose n?uz n. 端部，管口端部，管口?feed fi:d n. 进给进给?lever li:v? n.杠杆，手柄，杠杆，手柄，把柄把柄?jaw n. 卡爪，虎钳牙卡爪，虎钳牙.?chuck t?k n. 卡盘，夹具卡盘，夹具 v. 用（卡盘）夹紧用（卡盘）夹紧?leadscrew

3、li:dskru: n. 丝杠，丝杠，螺杆螺杆?thread red n. 螺纹螺纹?pitch pit? n. 螺距，间距螺距，间距?turret lathe 转塔车床，六角转塔车床，六角车床车床?transverse movement 横向横向运动运动?reversing lever 反向柄反向柄?feed-shaft 光杠光杠?live center 主轴顶尖，活动主轴顶尖，活动顶尖顶尖?dead center尾架顶尖，固定尾架顶尖，固定顶尖顶尖?three-jaw universal chuck 三三爪万能卡盘爪万能卡盘?four-jaw independent chuck四爪卡盘四爪

4、卡盘Have a rest please!二、二、TextThe lathe is one of the most useful and versatilemachines in the workshop, and is capable of carrying out a wide variety of machining operations. The main components of the lathe are the headstock and tailstock at opposite ends of a bed, and a tool-post between them whic

5、h holds the cutting tool. The tool-post stands on a cross-slide which enables it to move sideward across the saddle or carriage as well as along it, depending on the kind of job it is doing.二、二、TextThe ordinary center lathe can accommodate only one tool at a time on the tool-post, but a turret lathe

6、 is capable of holding five or more tools on the revolving turret. The lathe bed must be very solid to prevent the machine from bending or twisting under stress .The headstock incorporates the driving and gear mechanism, and a spindle which holds the workpiece and causes it to rotate at a speed whic

7、h depends largely on the diameter of the workpiece. A bar of large diameter should naturally rotate more slowly than a very thin bar, the cutting speed of the tool is what matters. 二、二、TextTapered centers in the hollow nose of the spindle andof the tailstock hold the work firmly between them. A feed

8、-shaft from the headstock drives the tool-post along the saddle, either forwards or backwards, at a fixed and uniform speed. This enables the operator to make accurate cuts and to give the work a good finish. Gears between the spindle and the feed-shaft control the speed of rotation of the shaft, an

9、d therefore the forward or backward movement of the tool-post. The gear which the operator will selectdepends on the type of metal which he is cutting andthe amount of metal he has to cut off. 二、二、TextCenters are not suitable for every job on the lathe. The operator can replace them by various types

10、 of chucks, which hold the work between jaws, or by a front-plate, depending on the shape of work and the particular cutting operation. He will use a chuck, for example, to hold a short piece of work, or work for drilling, boring or screw-cutting. A transverse movement of the tool-post across the sa

11、ddle enables the tool to cut across the face of the workpiece and give it a flat surface. For screw-cutting, the operator engages the lead-screw, a long screwed shaft which runs along in front of the bed and which rotates with the spindle.二、二、TextThe lead-screw drives the tool-post forwards along th

12、e carriage at the correct speed, and this ensures that the threads on the screw are of exactly the rightpitch. The operator can select different gear speeds, and this will alter the ratio of spindle and lead-screw speeds and therefore alter the pitch of the threads. A reversing lever on the headstock enables him to reverse the movement of the carriage and sobring the tool back to its