Abstract: A vane groove grinding apparatus for compressor cylinder including a compressor cylinder holding means the compressor cylinder being provided with an inner hole and a vane groove extending radially outwardly from the inner hole, sliders being movable along a center line of the inner hole and at a right angled direction to the vane groove, a grinding disk holder facing one open side of the inner hole and a support for locking the holder facing another open side of the inner hole both being disposed on a slider adjacent to the compressor cylinder, when the grinding disk is inserted in the vane groove a distal end of the grinding disk holder is firmly engaged in the support.

Abstract: A grinding wheel position detecting means for a surface grinding machine, in which a super-grain grinding wheel is composed of a base metal fastened to a longitudinal end portion of a rotating shaft and a super-grain layer provided on a longitudinal end face of said base metal, and a longitudinal end face of the super-grain layer is utilized as a grinding surface.