| 摘要 |
PURPOSE:To prevent damage of a stopper for specific measurement and a reference surface board by comparing the number of revolutions of the stopper given a change by a certain force with the set number of revolutions at the time of lapping completion, judging the completion of lapping, and thereby uniforming the finish dimensions and surface roughness. CONSTITUTION:When the time T has passed after commencement of lapping, a control device M actuates a cylinder 11 to allow an arm 9 to advance in the D direction, which causes the arm 9 to contact a stopper 3 as well as a rotation sensor S to sense the number of revolutions of the stopper 3. These are fed into the control device M. If at this time the ends of three stoppers 3 contact a reference surface board 2 because of the work 6 being lapped into a specific dimension, the gringing resistance will lessen rapidly to decelerate the rotation of a jig 4 and also to decelerate the rotation of the stoppers. Now the number of revolutions R of the stoppers 3 is fed into the control device M to be compared with the set number R0 for judging completion of lapping. If R<R0, it shall be judged that the lapping is completed, and the arm 9 is retracted and the lapping machine stopped. This arrangement will assure a uniform finish dimension and surface roughness. |
