GB604532A - Improvements in adjusting mechanism for a honing tool - Google Patents

Abstract

604,532. Grinding cylinders. BURGESS, A. F. (Barnes Drill Co.). Nov. 26, 1945, No. 31842. [Class 60] [Also in Group XXIX] Adjusting mechanism for a honing tool having radially shiftable abrasive elements comprises, in combination, a member movable longitudinally to shift the abrasive elements of the tool, means for imparting movement to said member including a cylinder closed at both ends, a piston reciprocable in said cylinder and having a piston-rod engageable with said member in the forward movement of the piston, means for supplying pressure fluid to the rear end of said cylinder to move said piston forwardly, said piston acting in such movement to force out fluid trapped in the forward end of the cylinder, and means for metering the discharge of fluid from the forward end of said cylinder in predetermined increments released at accurately timed intervals, and means for varying the lengths of the intervals between successive increments to control the rate at which the abrasive elements of the tool are shifted. The honing tool 20 is mounted on tubular member 19 connected to head 10 which carries a motor M1 for rotating the honing tool, the head 10 being reciprocated by flexible driving members 12 passing round reversible drum 13, driven by motor M through reversing mechanism 14, preferably of the hydraulic type. The head 10 carries a cylinder 26 in which is a piston 25 which through its rod 29 and a push rod 32 effects the expansion of the tool. Pressure fluid is supplied to the cylinder by a pump P driven by motor M2 under the control of a distributing valve V actuated by a solenoid S in parallel with the tool-rotating motor M1. A non-return valve V1 permits entry of fluid into the right-hand end of the cylinder when the piston is to be moved to the left (to collapse the tool), but during movement of the piston to the right causes fluid to exhaust through a metering device comprising a plunger 40 continuously reciprocating in a cylinder having spaced ports 43, 44 connected respectively to the right-hand end of the cylinder 26 and to exhaust; the plunger 40 is provided with an annular groove 42 whereby at each reciprocation of the plunger, a definite quantity of fluid is removed from the right-hand end of the cylinder 26, the size of the groove in the plunger determining the resultant movement of the piston 25. The plunger 40 is reciprocated by the electric motor M2 which drives the pump P, the reciprocation being effected through belt 60, variable speed gearing 56, a crank-pin and a pivoted lever 46; by alteration of the ratio in the gearing 56, the frequency with which the movements of the piston 25 occur can be varied. A stop 77 on the piston-rod 29 serves to hold the non-return valve V1 open so that the metering is ineffective, permitting rapid expansion of the tool until the honing elements contact the work; the piston 25 has then reached a position in which the stop 77 allows the valve V1 to close under a spring; the valve V1 can be opened by the operator at any time by means of a solenoid S 1.