GB1038435A - Indexing means for grinding wheel dressers - Google Patents

Abstract

1,038,435. Trueing grinding wheels. LANDIS TOOL CO. April 23, 1965 [April 27, 1964], No. 17157/65. Heading B3D. Apparatus for dressing a grinding wheel 15, Fig. 3, comprises a dressing roller 20 mounted for rotation in a plane normal to the plane of the grinding wheel and disposed so as initially to engage the grinding wheel by one edge, feed means 14 for moving the dressing roller relative to the grinding wheel for a dressing operation, and incremental actuating means for indexing the dressing roller. The dressing roller is mounted on a shaft 21, Fig. 2 (not shown), rotatably supported in bearings 50 in a housing 22 which is carried by a bar 24 in a slide 12 movable to and from the grinding wheel by an hydraulic motor 32. The slide carries a follower 31 having the same diameter as the dressing roller and engaging a stationary template 30 corresponding to the grinding wheel so that as a carriage 11 supporting the slide is moved by an hydraulic feed motor 14 over the machine bed 10, the motor 32 also acts to urge the follower against the template so that the roller dresses the sides and face of the grinding wheel, which may be used to grind a crank-pin. The shaft 21 of the roller has an extension 57 in a housing 25 which is mounted on housing 22 and supports a motor 55 having a disconnectable coupling with the extension 57, whereby the dressing roller may be continuously rotated if desired. The housing 25 encloses a one-way clutch 60 having a rotor 62 which has an arm 61 movable by a rod 65 connected to pistons 66, 67, rotation of the rotor in one direction causing balls 63 to engage and rotate the extension 57 and hence the dressing roller. A toothed collar 68 is secured to the shaft and a plunger 69 is urged by a spring 72 towards the teeth of the collar, the spring being insufficient to cause the plunger to prevent rotation of the collar during indexing. The plunger is urged against the collar by hydraulic pressure to prevent rotation of the roller during dressing. In operation, the operation of the motors 14, 32 are of the pistons 66, 67 and plunger 69 are controlled by a relay circuit controlling solenoid-operated valves. When a push-button is pressed to instigate a dressing operation, a solenoid moves a valve so that hydraulic pressure acts on piston 67 to move the arm 61 and rotor 62 in one direction and then on piston 66 to move them in the opposite direction to effect an indexing movement of, say, 6 degrees, to the dressing roller, fluid pressure then being directed to plunger 69 to prevent further rotation of the roller. The motor 14 is then operated to move the roller across the grinding wheel and back again, the follower and template controlling the path of the roller. The axis of the roller is inclined to an axis at 90 degrees to the axis of the bar 24 so that an edge of the roller engages the grinding wheel. As the roller wears, it retains its same diameter until the other edge is worn, whereupon it is replaced.