机械制造技术基础英文课件CHAPTER6 - 图文

7.2.2 Error of the machine tool

Errorofthemachinetoolreferstothemanufactureerror,setuperrorandwearcome

fromthemachinetoolwithoutcuttingforce.

7.2.2.1spindlerotationalerror（1）conceptofspindlerotationalerror

Theoretically,the position of the rotational axis of the spindle in the space is fixed, or in another word, the instant speed is zero.But in

practice,there are a lot of factors influence the position of the spindle and make the spindle position change instantly. We call the maximum floating value in the sensitive direction of the error the rotational error of the spindle.

There are three types of spindle rotational error, shown below：movieFig.1 the three types of the spindle error of the machine tool(a) Pure radial jump (b) pure axial jump (c) pure angular move

Pure radial jump ：The practical axis is parallel to the desired axis, but jump in constant amplitude

Pureaxialjump：Thepracticalaxismovesalongthedesiredaxiswith

constantamplitude.

Pureangularmove：Thepracticalaxismovesinclinedtothedesiredaxiswitha

constantamplitude,andthejointpointkeepsconstant.

（2）influence of the spindle error on machining accuracy

Differentrotationalerrorofthespindlehasdifferentinfluenceonthemachiningaccuracy,eventhesamerotationalerrorhasdifferentinfluencewhenthemachiningmethodisdifferent,shownasFig.6.5、6.6、6.7、6.8andtable6.1.

(a) Turning influenced by radial jump(b) Boring influenced by radial jump

moviemovieEnd surface influenced by Angular move

Boring influenced by Angular movement error

movieTable 1 influence of the spindle error on the surfaces under different machining method