To quickly perform squaring of a reference face in a workpiece with high precision without requiring much labor by projecting two fixed pins on the inside face of a fixed part, and projecting a single pressing pin protruded in the vertical intermediate position of the two fixed pins in a strickle arranged freely slidably.
After a workpiece W is positioned between a fixed part 2a and a movable part 2b and between two fixed pins 5, 6 and a single pressing pin 8, a strickle 7 is pulled toward the two fixed pin 5, 6, sides, and the pressing pin 8 arranged in the strickle 7 is brought into linear contact with a rear face Wb in the workpiece W, while a front face Wa in the workpiece W is brought into linear contact with the two fixed pins 5, 6, so that the workpiece W is prevented from moving in the lateral direction and uniform force is applied to the fixed pins 5, 6. Then, the movable part 2b, a mouthpiece 4, and the strickle 7 are moved toward the fixed part 2a side and a mouthpiece 3 side, so that the workpiece W is held and fixed, and then, an upper face to the front face Wa in the workpiece W is ground, and as a result, respective faces can be used as reference faces for the X-face and the Y-face.
TODA SHINICHI
KIMURA SHOICHI
MATSUMOTO NOBORU
NAGASHIMA TAKESHI
TAKAHASHI NAOKI