Question

The XY table of a NC machine tool is to move from P(1, 1) to O(51, 1); all coordinates are in mm. The pitch of the NC drive leadscrew is 1 mm. If the backlash between the leadscrew and the nut is 1.8°, then the total backlash of the table on moving from P to Q is _______ mm (round off to two decimal places).  

Answer 1

Concept:

Pitch: It is the linear distance covered while revolving a complete 360° turn.

Calculation:

Given:

Pitch = 1 mm, Backlash in terms of degree = 1.8° and Backlash in linear measurements = ?

For 360° rotation linear movement covered is 1 mm.

For 1.8° rotation, the linear movement covered is \(\frac{1}{360}\times1.8=\frac{1}{200}\;mm\)

The tool is moved from point P(1, 1) to point O (51, 1) i.e. 50 mm.

∴ the backlash that occurred while covering 50 mm is \(50\times\frac{1}{200}=0.25\;mm\)