GB376434A - Improvements in or relating to grinding or abrading machines - Google Patents

Abstract

376,434. Grinding. CINCINNATI GRINDERS, Inc., 3058, South Street. Cincinnati, Ohio, U.S.A. May 26, 1931, No. 15391. Convention date, May 27, 1930. [Class 60.] Round holes, enlarging and trueing; guides and r e s t s trueing rotating tools. -A grinding-machine comprises a grinding-head reciprocated axially of the grinding-wheel, a work-head movable axially of the grinding-wheel to bring the work into and out of grinding position and movable transversely to feed the work into the wheel, and means for interrupting the cycle of operation to true the grinding-wheel, the reciprocation of the wheel being stopped and the speed of the work-table, which carries a trueing diamond, being reduced during the trueing. The machine is shown as an internal centreless grinder and comprises a bed 10 having thereon ways 11, 12 respectively carrying a wheel-head 13 having thereon an electric motor 14 driving a grinding-wheel 16, and a work-head consisting of a base 39 carrying a transversely movable slide 42 upon which is a work rest 43, a regulating-wheel 46, and a member 47 for pressing the work 45 against the rest and the wheel. The grinding-head is reciprocated by a piston 26 in a cylinder 25 controlled by a reversing-valve 22 movable by a lever 33 actuated by dogs 34, 35 and supplied with fluid from a pump 19, and the work-head is moved on the ways 12 by a piston 54 controlled by a valve 51. The valve 51 is moved to stop the work-head with the work in. grinding position by a trip dog 61 which actuates a lever 63, a link 64, and a lever 66. and whilst in this position, the work is fed into the grinding-wheel until rearward movements of the work and ejection thereof are initiated by a gauge ; the valve 22 exhausts through a valve 29, and the valve 51 exhausts through a valve 57. Upon the work-head is a trueing-diamond 105 carried by a post 104 on a rod 103 connected to a piston 101 in a cylinder 102, and on the work-head also are dogs 68, 69. The dog 69 is adapted to move a plunger 72 which actuates, through a rock shaft, a pawl 81 and a ratchet wheel 82, a plate 87 carrying one or more cam points 88, which close a switch 91 and thereby, through a solenoid 96 and lever 97 move the valve 57 so that the exhaust from the piston 54 is throttled by a valve 126, and fluid is admitted to the cylinder 102 to move the trueing tool into operative position. The lever 97 also closes a switch 114, so that upon closing of a switch 111 by a dog 109 on the wheel-head, the valve 29 is moved by a solenoid 115 to stop the reciprocation of the wheel. Continued movement of the wheelhead causes the dog 68 to depress a plunger 127 to close a switch 121 and thereby, through other switches and solenoids 122, 123 to restore the valves, and the movements of the machine parts to the normal. The cam-plate 87 may have any desired number of cam points 88 thereon so as to cause trueing of the grinding- wheel after completion of each work-piece or after completion of any desired number of work-pieces.