Abstract
In a mechanism which grinds a gear by means of a form-shaped grind wheel, it's possible to set a grinding wheel dressing device and an index head independently. Therefore this mechanism is simplified in comparison with generating one by a grind wheel remarkably. But, in the process of form grinding, the dressing attachment is required which dresses any desired tooth form modification accurately and efficiently. First, it's the purpose of this paper to obtain the circular arc which is a fairly good approximation to an involute curve secondly to manufacture a simple designed dressing attachment which forms a grind wheel along above mentioned circular arc, and to grind a high precision gear by means of a form-shaped grind wheel by this one. The approximate arc is obtained by the least squares method, by which it's possible to obtain the specification of the circular arc which holds to a fairly good approximation easily, in addition, to adapt to modified profiles. In an experiment, the grind wheel is formed by the dressing attachment which is moving on a circular arc and tooth spaces were grinded by the form-shaped grind wheel. The results of profile measurements show the deviation from calculated values and experimental ones are within 4μm. It is assured that the accuracy of a combination of a polygon mirror and an autocollimator which is used as indexing device is copied to a work gear exactly.
