毕业设计外文翻译.docx

1、毕业设计外文翻译毕业设计外文资料翻译题 目 钻铣床工作台及变速箱结构设计 学 院 机械工程学院 专 业 机械工程及自动化 班 级 xxxx 学 生 xxxxx 学 号 xxxx 指导教师 xxx xx 年 x月 x 日 United states patent,1997,36(7):US005611137AMACHINE TOOL，MORE PARTICULARLY FOR DRILLING AND MILLING Assistant Examiner-Christopher KirkmanYale UniversityAbstract machine tool more particular

2、ly for drilling and milling, possesses a machine bed, on which a power driven slide is adapted to run horizontally on rails. A machining head having a rotary drive device for at least one table forming part of said head, is power moved on the longitudinal slide in at least one further direction of m

3、ovement. The machine bed possesses two spaced lateral walls, whose intermediate space is designed to serve as a machine zone for receiving at least one work holding means.on the two lateral walls two parallel guide rails are arranged for the longitudinal slide, a third guide rail being arranged with

4、 an offset in the longitudinal direction between the two other guide rails. The longitudinal slide is guided using three guide elements on the three guide rails, the power drive being at or adjacent to the central guide rail. On this arrangement a clamping yoke of relatively light design may be empl

5、oyed, which only requires one central drive. Transverse forces caused by twisting in the case of eccentric loading act perpendicularly on the guide elements, which are better able to withstand the forces.Keyword hole drilling, milling, rail, funnel transmission system. 1 BACKGROUND OF THE INVENTIONT

6、he invention relates to a machine tool more particularly for drilling and milling, comprising a machine bed, guide rails mounted on said bed, a power driven longitudinal slide adapted to run horizontally on said rails on said bed, a machining head, and a rotaiy drive device forming part of said head

7、 for at least one tool, said head being adapted to be power moved on the longitudinal slide in at least one further direction of movement.2 THE PRIOR ARTA machine tool of this type designed in the form of a milling machine is disclosed in the German patent public 4,203,994 C. In the case of this wid

8、ely employed type of milling machine the slide moves in the longitudinal 20 direction and the machining head is arranged on the slide for vertical motion. Movement in the transverse direction is performed using a suitably driven work table. Complex measures must be taken to protect the drive of such

9、 table in the bottom part of the machine against material such as 25 shavings and radicallubricant during operation. In the case of a major lateral deflection of the work table there is the danger of deformation，albeit only slight, owing to the mass of the machine and of the work and owing to forces

10、 acting by way of the tool so that in practice the work table does not move 30 along a linear path but along a circular path with a radius of several kilometers in order to compensate for deformation in order to be able to absorb it.So-called gantry milling machines are known as well, in the case of

11、 which the longitudinal slide bearing the machine head runs on two parallel rails, which for their part are arranged on the top side of two lateral walls of the machines bed. In this case the longitudinal slide is borne by four guide elements on the two guide rails. Furthermore for 5 axis machining

12、either the machining head must be complex in design so that it can be pivoted, or the work table, which is borne on one bottom wall of the machines bed，must be designed to pivot with the result that there is a danger of lubricant and coolant finding its way into the drive of the work table unless co

13、mplex.3 SHORT SUMMARY OF THE INVENTIONOne object of the invention is to create a machine tool more particularly for drilling and milling of the type initially mentioned, in the case of which, in a manner similar to a gantry construction, all drive elements, guides and bearings are arranged above the

14、 dirt, coolant and lubricant zone, but in which however the longitudinal slide makes do with a 55 simpler and less expensive drive device while maintaining the same or an even higher degree of machine.In order to achieve these and/or other objects appearing from the present specification, claims and

15、 drawings, in the present invention the machine bed possesses two spaced lateral walls defining an intermediate space between them, which is designed in the form of a machining zone adapted to accommodate at least one work holding means, on the two lateral walls two parallel guide rails for the long

16、itudinal slide are arranged, a guide rail is arranged which is half way between the two other guide rails with an offset in the longitudinal direction, and the longitudinal slides guided using three guide elements on the three guide rails, the power drive being at or adjacent to the central guide ra

17、il.MACHINE TOFirstly the machine tool in accordance with the invention possesses all the advantages of a “gantry” construction. All 5 the main working movements are performed by the tool, whereas the work to be machined rests on the machines bed. Accordingly the mass moved is constant and the machin

18、e tool may readily be bound in place at a palette station, the tool changer attached in position being simple. Owing to the stationary arrangement of the work to be machined in the machine bed, that is to say between the two lateral walls, all drive elements, guide elements and bearings are above th

19、e work, that is to say outside the dirt area, into which shavings, lubricant and coolant descend. Owing to the arrangement above the machine bed all drive elements can be readily reached for servicing and substitution. The paths of force transmission between the tool and the work are short and lead

20、to a high degree of rigidity of the machine. In this respect a compact manner of construction is produced, that is to say the overall dimensions are small for the large size of machining cut possible with the machine tool. The machine comprises but a few components and can be clad in simple manner.

21、Owing to the triple point support for the longslide designed in the form of a gripping yoke the design is lighter in weight and only a single central drive at or adjacent to the central guide rail is required, something leading to a significant x eduction in costs in comparison with known arrangemen

22、ts. Since the drive acts directly on the central guide element, it is directly on the displacement measuring system, something leading to precise machining. The resulting forces, which are produced by skew running in the case of eccentric loading of the longitudinal slide, act perpendicularly on the

23、 guide element with the result that the forces which occur may be better taken up. This as well is 35 something conducive of an increase in machining precision. The measures defined in the claims relate to advantageous further developments and improvements in the novel machine tool as indicated abov

24、e.All three guide Tails are preferably arranged in the same horizontal plane and, after production of the blank of the machine bed, may hence be ground by a larger machine tool after attachment in it.The central guide rail is at least partially on a transverse wall connecting the two lateral walls a

25、t terminal parts thereof, such transverse wall contributing to an increase in the structural rigidity of the machines bed. In this case the transverse wall will preferably possess a central spur on its side opposite to the machining zone in the longitudinal direction of the machine bed, such spur se

26、rving as a support for the central guide rail and partially taking up the weight of the longitudinal slide.For exactly fixing and aligning a work table on the lateral walls the machining zone has support surfaces for the table. The support surfaces are in this respect designed in the form of surface

27、s machined by the machining head and which accordingly lie in a plane which is exactly parallel to the 60 plane of motion of the longitudinal slide. The fixing of the work table is in this case performed at a particularly rigid part of the machine bed.At its lowermost terminal part the machining zon

28、e poss an ejection opening for shaving sand lubricant, which 65 fall under gravity automatically through the ejection open. Underneath the ejection opening there is preferably a receiving container and/or a removal device, at least for the shavings.In order to permit and ensure motion of the machini

29、ng head or, respectively, of the tool arranged thereon in all three 5 possible directions thereof, the machining head is arranged so that it can be power moved vertically on a transverse slide, which transverse slide is moved by power on the longitudinal slide in the transverse direction.Owing to th

30、e complex and compact form of the machine 10 bed constituting a machine base, the same can consist of a cast mineral material, more particularly polymer concrete. Accordingly there is on the one hand a high degree of structural rigidity and on the other hand a reduction in costs, exact dimensions on

31、 removal from the 15 mold and advantages as regards machining.In an advantageous design the lateral walls can be employed additionally as carriers for work holding means, such as pivoting tables, a fastening point for at least one work holding means being provided at each of the two lateral walls, t

32、he two fastening points being aligned in a horizontal line athwart the longitudinal direction of the guide rail. The fastening points are in this case preferably through openings with a circular of polygonal form. Such receiving recesses may for example be precision machined together with the guide

33、rails once the machine bed has been clamped in place so that same possess an exact mutual alignment Such work holding means may be supported so that they may be turned by power or manually and for instance machining of a surface inclined about two axes is possible. In this case the forces occurring during m