A NEW KIND OF GEAR MEASUREMENT TECHNIQUE

A new method of gear measurement is introduced in this paper. It is ba sed on the traditional gear single-flank measurement, but it uses a sp ecial master gear with three kinds of measuring tooth and a tranmissio n tooth. The first kind of measurement tooth has a projective involute which is used as a reference. When it is engaged in mesh with the too th of the workpiece, the deviation of transmission reflects the involu te profile error of the workpiece. When a projective helix on the seco nd kind of measurement tooth is meshed with the tooth of the workpiece the lead error can be obtained. Because the third kind of measurement tooth is the same as that used by a traditional single-flank tester, the tangential composite error can be easily obtained. The transmissio n tooth-whose thickness is reduced-is used to make the contact ratio l ess than one. When the new master gear is meshed with the workpiece fo r several turns the pitch error of the latter can be measured. Experim ental results using equipment based on the new technique have shown th at the method is feasible and efficient.