VALVE SLEEVE OIL PASSAGE GROOVE CHAMFERING SECTION FORMING METHOD

PURPOSE:To easily and quickly form chamfering section on the edges on both sides in the cross direction of a rotor groove by aligning the shaft line of a cylindrical grinding wheel and the center in the cross direction of a sleeve groove and abutting the cylindrical grinding face of the cylindrical grinding wheel on the tops of the edges on both sides in the cross direction of the sleeve groove by means of proper pressing force to rotate the cylindrical grinding wheel. CONSTITUTION:A valve sleeve whose interior is hollow is properly fixed. On the internal circumferential of the valve sleeve a plurality of axially directional sleeve grooves 5, 5... are radially formed. In the next step, a cylindrical grinding wheel 10 whose external diameter is smaller than the internal diameter of this valve sleeve is inserted into the valve sleeve so as to be aligned with the shaft line of the valve sleeve, and the shaft line L10 of the grinding wheel 10 and the center L5 in the cross direction of the sleeve groove 5 are aligned. In the next step, the cylindrical grinding face 10a of this cylindrical grinding wheel 10 is abutted on the top sections Q and Q of the edges on both sides in the cross direction of the sleeve groove 5 by proper pressing force to rotate the cylindrical grinding wheel 10. As a result on both sides in the cross direction of the sleeve groove 5 chamfering sections 6 and 6 are simultaneously formed.