Method for inspecting gear contact patterns

DETAILED DESCRIPTION We claim: 1.
Method for inspecting a gear contact pattern on a tooth surface of a gear tooth of a gear which comprises the steps of determining on the tooth surface of the gear tooth a plurality of regularly located measuring points, establishing a standard tooth profile for the measuring points, measuring the tooth surface at the measuring points to detect deviations of the tooth surface from the standard tooth profile at the measuring points, determining a reference which is the deviation of maximum positive value, counting the number of the measuring points of which deviations are within a predetermined limit of the reference, determining a gear contact ratio which is a ratio of the counted number of the measuring points to the total number of the measuring points so as to select gears in which the gear contact ratio is above a predetermined value.
2.
Method in accordance with claim 1 in which said measuring points are in a equi-spaced matrix pattern.
3.
Method in accordance with claim 1, said method being applied for inspecting a gear contact pattern in a gear for automobile use, said predetermined limit of the deviation from the reference being 6 microns.
4.
Method in accordance with claim 3 in which said predetermined value of the gear contact ratio is 0.
30.
5.
Method for inspecting a gear contact pattern in accordance with claim 1 in which an unselected gear is paired with another type of unselected gear which is to be meshed with the first mentioned unselected gear, said method further comprising the steps of comparing the deviations in one gear with corresponding deviations in the other gear to detect relative deviations at the measuring points between the pair of gears, counting the number of measuring points wherein the relative deviations are within a predetermined limit and judging the pair of gears as acceptable where the counted number of such measuring points is greater than a predetermined value.
6.
Method in accordance with claim 5 in which said measuring points are in a equi-spaced matrix pattern