英語(yǔ)翻譯
The error of measurement of a zero-type MH in a NC machine should be accounted for in assigning the automatic workpiece basing cycles,in the case of basing on a cylindrical pin or hole,the basing error will be eat = 0.5(o w + o a + Smi n) 2,where o w is tolerance on the base dimension of the workpiece; o a is the tolerance on the base dimension of the at- tachment; Smi n is guaranteed clearance.
The value of Smi n is usually selected in the 0.005-0.02 mm range.Tolerance on the base dimension of the attachment with the base element diameter of not less than i0 mm is 0.01-0.02 mm.By substituting the obtained data in (i),we get o w > 0.035 mm.
Use of MH in multipurpose NC machines showed that these did not find use for direct measurement of workpiece dimensions.
Exceptions to the above are cases of control of dimensions of nonrigid workpieces.The automatic basing cycles worked out facilitate elimination of manual trueing of the workpiece or attachment on the machine tool and makes it possible to do away with the use of attach- ments with workpiece basing elements for individual production