GB729890A - Crankshaft grinding machine - Google Patents

Abstract

729,890. Grinding crankshafts. TEISEN, M. R. G. Oct. 5, 1953 [Oct. 11, 1952], No. 27329/53. Class 60. A crankshaft grinding machine comprises a frame 1, Fig. 1, a grinding wheel 10 mounted for rotation about a stationary axis, means for supporting a crankshaft 24 for rotation about its normal axis of rotation, means for guiding the support. ing means so as to permit transverse movement in any direction of the normal axis of the crankshaft, and means for keeping a crank pin to be ground in correct working position relative to the grinding wheel. The grinding wheel is supported by a slide and connected by a V-belt drive with a motor 13. An arm 15 angularly adjustable by a worm gear 17 is also supported by the slide and is provided with a notch 16 which holds the crank pin to be ground in fixed relation to the grinding wheel. A chuck 25 and a centre support and drive the crankshaft about the axis of the pin to be treated and are mounted on a framework which permits them to move in a circular path transverse to the crankshaft axis. This framework consists of two brackets 22, 23 secured to a tubular member 21 rotatably mounted between a pair of arms 18, 19 pivotally connected to columns 2, 3 on the machine frame. In setting up the machine, the weight of the crankshaft is first balanced about the axis of the member 21 and then balanced about the pivots of the arms 18, 19. This is accomplished automatically by a valve 32, Fig. 4, which may be connected to a lever 28 coupled to a counterbalance arm 26 and the arms 18, 19 by a spring 30 and hinged rods 27, 29. When the crankshaft is first mounted in the machine, the arms 18, 19, the lever 28 and the valve 32 move counterclockwise so that an arm 38 secured to the latter urges a piston 40 towards the bottom of a cylinder 41. The oil pump of the machine is now connected to a duct 42 to lift the piston until a duct 48 therein registers with a duct 45 to permit oil to pass to a chamber 47 and compress the spring 30. When the oil pressure reaches a value corresponding to balance about the axis of the member 21, the piston is further displaced to stop the oil supply to the chamber 47 and to move the valve 32 to connect the cooling water pump of the machine to a drum 20 rigidly connected to the arms 18, 19. Once the drum 20 has received enough water to balance the weight of the crankshaft about the pivots of the arms 18, 19, the latter swing clockwise and hence cause the valve 32 to cut off the water supply to the drum 20. The valve 32 is locked to the machine frame during grinding and is operated manually to empty the drum 20 and the chamber 47. The journal portions of the crankshaft may be ground by locking the arms 18, 19 and the member 21.