GB625656A - Trimming tool and mechanism for grinders and other rotary cutting tools - Google Patents

Abstract

625,656. T r u e i n g grinding-wheels. NEWTON, E. P. (Gear Grinding Machine Co.). Oct. 31,1945, No. 28942. [Class 60] [Also in Group XXII] A mechanism for trimming cycloidal surfaces on grinding wheels by means of a trimmer point is provided with a pivot in its mounting member, permitting a limited rotation of said trimmer point when the mounting member is stationary to trace an arcuate curve, and an arcuate member fixed on a frame, the mounting member being constrained to roll about the periphery of the arcuate member so that the trimmer point moving therewith traces a cycloidal curve. The mechanism includes a frame C mounted between work centres D. D<SP>1</SP> and given the same rotation and axial movement as the work to be ground by the grinding wheel by means in which, Fig. 8, a rack bar P<SP>2</SP> engaging a stationary inclined bar Q at one end meshes with a gear train P<SP>1</SP> to rotate the frame C as it moves longitudinally. On a shaft E rigidly mounted in the frame C and concentric with the work centres is fixed a gear segment F on which rolls in mesh with it a gear segment F fixed on a shaft H journalled in a frame G pivotally mounted on the shaft E. Fixed to a head portion H<SP>3</SP> of the shaft H is a carrier J in which is rotatably mounted about a pivot J<SP>1</SP> in alignment with the pitch circle of the gear F' a support Ka, Kb for the trimmer K<SP>8</SP>. When the handle K<SP>5</SP>, attached to the trimmer support Ka is actuated it and the carrier J move about and with the shaft H which, owing to the meshing of the gear segments F, F<SP>1</SP>, also rolls about the gear F, and the tool K<SP>8</SP> thus traces out a cycloidal curve. Adjustable stops in the frame G limit the movement of the gear segment F<SP>1</SP> so that after part of a cycloid has been traced out the gear segments lock and the trimmer simply rotates about the pivot J<SP>1</SP> in the carrier J to trace out an arcuate path, an adjustable stop limiting this movement. The above described device traces out curves on a grinding wheel for grinding female work but a similar but slightly modified device will trace out curves on a wheel for grinding male work. Specifications 536,299 and 625,654 are referred to.