Patent GB-1047806-A (GB)
Title: Method of and arrangement for trimming grinding wheels
Inventor: PALMER RAYMOND LESLIE
IPC: B24B53/075
Filed: 1964-07-04
Abstract: 1,047,806. Trueing grinding wheels. CHURCHILL GEAR MACHINES Ltd. Sept. 27, 1965 [July 4, 1964], No. 27684/64. Heading B3D. A method of trimming a profiled grinding wheel comprises moving the wheel and a worktable 13 carrying a trimming head 15 to respective trimming positions, trimming both flank portions of the wheel simultaneously by moving a pair of flank trim elements 58, 59 from start positions to finish positions on the trimming head, moving the head in relation to the worktable to advance a root trim element 22 from an inoperative position to an operative position, moving the root trim element in an arcuate path in relation to the trimming head from a start to a finish position, and withdrawing the worktable and the wheel from their trimming positions. In a machine for carrying out the method, the work-table 13 is movable on slideways 11, 12 of the bed of the machine, which may be as described in Specification 1,047,807, and the trimming head 15 is movable along slideways 14 on the work-table by means of a piston-and-cylinder device 16, 18, Fig. 2 (not shown), the rod of the piston being connected to a bracket 17 on the work-table. The roottrim element, which may be a diamond 22, is mounted on a shaft 21 and is adjustable radially thereof by a micrometer 23. The shaft is rotatable in the head and is formed with a pinion 24 meshing with a rack 25 reciprocable by a double-acting jack to move the diamond in an arcuate path. A pair of sectors 28, 19 are mounted on the face of the head and can be angularly adjusted about the axis of the shaft to positions determined by a gauge 32 which co-operates with a fixed dowel 33 on the head and dowels 30, 31 on the sectors; the sectors are then locked in position by screws 38, 39 which engage the heads of pins 36, 32 with slots 34, 35 in the sectors. The sectors carry slides 40, 41 which are movable along guides (not shown) by the displacement of a cylinder 46 having a conical end engaging rollers 44, 45 on arms secured to the slides. Each slide carries a sub-slide 50, 51 on which is a bracket mounting a flank trim element 58, 59, the sub-slides being adjustable by screws 54, 55 to compensate for wear of the elements. When the grinding wheel is to be trimmed, the work-table is moved to position the flank trim elements in the vertical plane containing the wheel axis. The cylinder 46 is advanced so that its conical end moves the rollers 44, 45 to cause the slides 40, 41 to move along their guide and the elements 58, 69 to trim the flanks of the grinding wheel. When the elements are in their finish position the cylinder is stopped and the jack for moving the rack 25 is actuated to move the root trim element 22 from its intermediate position shown in Fig. 1 to its start position. The trimming head is then moved by the piston-and-cylinder device 16, 18 to move the root trim element to its operative position wherein the rack 25 is moved by its jack to rock the root trim element from its start to its finish position. When the finish position has been reached, the trimming head is returned to its initial position, the slides 40, 41 with their flank trim elements are returned to their start positions, and the root trim element is moved to its intermediate position. The various movements of the machine are controlled by limit switches.