Angular Measurement and Circular Division

PRECISION ROLLERS

Fig. 4.4. Measurement of taper plug gauge.

In triangle ABC it is seen that h is the height of the gauge blocks and BC=(M2 -MJ/2, in which Mi and M 2

' D x r

are the measurements over the rollers .

... (I)

Thus the semi-angle of taper can be determined by direct measurement.

Fig. 4.S. Measurement of the diameter of the small ~nd of a taper plug gauge.

To find the maximum and minimum diameters at the top and bottom of the step it is first necessary to determine D,, the diameter at the small end. Fig. 4.5 represents the small end of the gauge during the measurement of Mi.

It is seen that

Mi=Da+2r+2x and from Fig. 4.5

90-8 r tan--=-

2 x . (90- 8) . ·. x = r x cotangent 2

( 90- 8) ••. 1¥1 =D,+2r I+cot - 2-

( 90-8) or M 1 =D,+d I +cot - 2- whered=rollerdia.

( 90-8) .·. Ds=M 1-d l+cot--2-

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