GB471791A - Improvements in apparatus for dressing abrading wheels - Google Patents

Abstract

471,791. Trueing grinding - wheels. NORTON CO. Feb. 5, 1936, No. 14040 /37. Convention date, Feb. 6, 1935. Divided out of 471,802. [Class 60] In a lapping-machine for treating cylindrical work, and comprising two conical laps 50, 55 mounted on skewed axes so that the workpieces are fed automatically along guides 158, a device is provided for trueing the laps, comprising an abrading-wheel 277 provided with a toric periphery and movable along the line of the guides 158 over the surface of the laps with its plane vertical; a device also is provided for dressing the wheel 277 so that the radius of curvature of the periphery in radial planes is equal to that of the work-pieces. The wheel 277 is carried by a head 268 adjustable by a screw 272 on a plate 265 carried by a carriage 213 which is movable on ways 211, 212 on a bed plate 206 angularly adjustable about a trunnion 205 carried by an apron 125 supported on the base 20 of the machine. The carriage 213 is moved by the engagement of a pinion 218, Fig. 3, thereon with a rack 217 on the bed 206, the pinion being driven in either direction by bevel gearing 222... 224, Fig. 4, and a sliding clutch sleeve 228 from a shaft 225 driven through belt and worm gearing by an electric motor 260 mounted on the carriage 213 ; the clutch sleeve may be moved by a lever 235, automatic operation being brought about by dogs 245, 246 at the ends of the bed 206 and a detent device 240 .. 243 serving to hold the lever 235 normally with the clutch in neutral position, or if required in extreme positions to ensure automatic reciprocation of the carriage 213. In operation, the cones 50, 55 are separated, the surface of each being trued separately by movement of the wheel 277 therealong. The periphery of the wheel 277 is trimmed to the required toric form by a diamond tool 211, Fig. 5, mounted in a slide 326 movable axially in a bore 327 in a quadrant arm 320 by a screw 333 and locked by a set screw 334, which engages an inclined flattened part 326 of the slide. The arm 320 is pivoted, by means of a spindle 313 in a boss 311 on a slide 306 movable bv a screw 307 on a member 295, which is removably mounted on a stud projecting from a collar 291 clamped by bolts 292 on a part 290 of the head 268. Before trimming the wheel, the diamond point is set to the required radius with respect to the axis of the spindle 313 by inserting a gauge-piece having the diameter of the work-pieces in a tapered bore 343 in the arm 320, and adjusting the diamond just to touch the gauge-piece : the gauge-piece is then removed and the wheel is trimmed by oscillation of the quadrant, by means of a handle 344 about the spindle 313. The wheel 277 is driven by the motor 260 through a belt 279 provided with a tensioning pulley 281 pressed by a spring.