Abstract: A centerless grinding machine comprises a stationary disk, a following disk, and a shoe, which cooperate to hold and rotate a workpiece. The following disk is mechanically loaded to the bias towards the stationary disk and the shoe so that the workpiece is secured between an outer circumference of the disks and the shoe. A diameter detector detects an outside diameter of the workpiece by detecting a displacement of the following disk by the workpiece. From this information, a controller controls an X-Z grinder to grind an inner surface of the workpiece. This grinding is in response to the outside detector detected by the diameter detector. As a result, the inner diameter can be machines to closer tolerances than are available in the outer diameter.

Abstract: A workpart chuck centering mechanism moves towards the axis of rotation of the chuck as the chuck rotates in an eccentric non-centered position. The centering mechanism includes two independent shoes. Each shoe is driven by a servo-motor and encoder. The two shoes function in a cooperative manner to center the workpart. A sensing device monitors any eccentric movement of the workpart and controls the positioning of the shoes. The two shoes and the sensing device are mounted on a base which can pivot about the chuck axis. The directions of movement of the respective shoes are displaced 90.degree. relative to one another and intersect at the chuck axis.

Abstract: A workpart chuck centering mechanism moves towards the axis of rotation of the chuck as the chuck rotates in an eccentric non-centered position. The centering mechanism includes two independent shoes. Each shoe is driven by a servo-motor and encoder. The two shoes function in a cooperative manner to center the workpart. A sensing device monitors any eccentric movement of the workpart and controls the positioning of the shoes. The two shoes and the sensing device are mounted on a base which can pivot about the chuck axis. The directions of movement of the respective shoes are displaced 90.degree. relative to one another and intersect at the chuck axis.

Abstract: Internal grinding machine having wheelhead mounted on an elongated cylindrical bar whose axis extends parallel to but substantially spaced from the axis of the abrasive wheel, the bar being mounted in bearings and the relative movements of the wheelhead for producing a grinding cycle being accomplished by rotation of the bar about its axis and by longitudinal motion of the bar along its axis.