INTRODUCTION

Coordinate measurements of gear real tooth surfaces enable us to determine surface deviations from the ideal surface. The goal is to minimize the surface deviations by proper correction of the initial machine-tool settings.

The technological aspects of the problem are as follows:

1. (i) The deviations of real tooth surfaces are inevitable due to surface distortion by heat-treatment, errors in initial machine-tool settings, deflection by manufacturing, and so on.

2. (ii) Application of an additional finishing operation for elimination of the deviations would be too expensive in comparison with the approach based on corrections of initially applied machine-tool settings. The advantage of this approach is the possibility of using the same equipment to correct the deviations. The disadvantage is that the approach will be successful only if the deviations are repeatable.

3. (iii) The coordinate measurements must be performed with high precision, which currently prohibits them from being performed simultaneously with the manufacturing. Therefore, the coordinate measurements are performed after manufacturing, but only the first gear of the whole gear set to be manufactured is tested.

4. (iv) In some cases master-gears are used and the coordinate measurements provide the information about the deviations from the master-surface for the surface being tested. The authors consider this approach less effective than computerized determination of surface deviations and corrections of machine-tool settings.

The described technique has been developed in response to the increasing requirements of high quality gear transmissions.