Abstract: The inner surface 2a of the input side disk 2 is composed of a near-inside-diameter portion, namely, a first arc surface 16 and a near-outside-diameter portion, namely, a second arc surface 17 in such a manner that the first and second arc surfaces 16 and 17 are allowed to continue with each other smoothly. The first arc surface 16 is formed as a single arc whose radius of curvature is R2a. Also, the second arc surface 17 is recessed in the axial direction of the input side disk 2 further than the extension of the single arc, and the second arc surface 17 is formed so as to have a spiral curve.

Abstract: The phase adjusting method is a method for holding a work including an end face formed symmetrical with respect to the axis of the work and a plurality of recesses respectively formed in a concave manner from the end face and also for positioning the position of each of the recesses around the axis of the work. Specifically, in the phase adjusting method, while holding the work in such a manner that it can be rotated around the axis thereof, the position of each of the recesses around the axis is detected. In accordance with the thus detected position of the recess around the axis, there is obtained a rotation angle by which the work is rotated around the axis thereof in such a manner the recess can be positioned at a given position around the axis of the work. And, based on the thus obtained rotation angle, the work is rotated around the axis thereof to position the recess at a given position around the axis of the work to thereby position the work.

Abstract: The phase adjusting method is a method for holding a work including an end face formed symmetrical with respect to the axis of the work and a plurality of recesses respectively formed in a concave manner from the end face and also for positioning the position of each of the recesses around the axis of the work. Specifically, in the phase adjusting method, while holding the work in such a manner that it can be rotated around the axis thereof, the position of each of the recesses around the axis is detected. In accordance with the thus detected position of the recess around the axis, there is obtained a rotation angle by which the work is rotated around the axis thereof in such a manner the recess can be positioned at a given position around the axis of the work. And, based on the thus obtained rotation angle, the work is rotated around the axis thereof to position the recess at a given position around the axis of the work to thereby position the work.

Abstract: The phase adjusting method is a method for holding a work including an end face formed symmetrical with respect to the axis of the work and a plurality of recesses respectively formed in a concave manner from the end face and also for positioning the position of each of the recesses around the axis of the work. Specifically, in the phase adjusting method, while holding the work in such a manner that it can be rotated around the axis thereof, the position of each of the recesses around the axis is detected. In accordance with the thus detected position of the recess around the axis, there is obtained a rotation angle by which the work is rotated around the axis thereof in such a manner the recess can be positioned at a given position around the axis of the work. And, based on the thus obtained rotation angle, the work is rotated around the axis thereof to position the recess at a given position around the axis of the work to thereby position the work.

Abstract: In measuring the accuracy of a thread groove of a ball thread formed in a nut by using an electric micrometer, a displacement of one point on each of a pair of flanks of the thread groove is measured along a longitudinal direction of the thread groove, and a pair of measured data sequences are obtained respectively for the pair of flanks. The data elements of the pair of measured data sequences are grouped into a plurality of groups so that each group includes a pair of data elements which are respectively contained in the pair of measured data sequences and which are corresponding to each other. The accuracy in the depth direction of the thread groove with respect to a reference thread groove is obtained on the basis of a sum of the data elements in each group, and the accuracy in the thread axis direction is obtained on the basis of a difference between the data elements in each pair.

Abstract: This invention provides a grinding method and a grinding machine therefor with controlled grinding force which detects the grinding force and grinding rate during operations, calculates in real time the threshold force and grinding wheel sharpness coefficient for each grinding cycle by an arithmetic operation unit, monitors the changes in sharpness of the grinding wheel, and properly changes values instructed by the grinding force commands based on the threshold force, the sharpness coefficient and the predetermined grinding rate value for controlling the feed of the grinding wheel. When the deflection of the grinding wheel shaft changes due to the changes in grinding force, the swivel angle of the grinding wheel shaft or a workpiece is adjusted to prevent the surface of the workpiece from tapering.