GB610023A - Improvements in and relating to apparatus for dressing grinding wheels and the like - Google Patents

Abstract

610,023. Dressing grinding-wheels. KESTELL, T. A. March 8, 1945, No. 5847. [Class 60] Apparatus for dressing grinding- wheels comprises a dressing tool holder, means for imparting to said holder a limited rotational reversible movement about one axis which can be preceded and/or followed by another limited rotational reversible movement about some other axis, and means for positively preventing one movement from taking place before the preceding movement has been completed. A diamond holder 2, Figs. 1, 3, is mounted to rock about and with a spindle 3, rockable by a handle 36, in a bracket 4, which is adapted to swivel about another spindle 5 perpendicular to the spindle 3. The rocking and swivelling movements are limited and controlled by two plungers 6, 7, Fig. 3, carried in the bracket 4 and engaging respectively an aperture 9 in a control plate 11 and either an arcuate slot 8 or an aperture 10 also in the plate 11. When either the plunger 7 is in the aperture 10 or the plunger 6 in the aperture 9 the arm 2 can be rocked about the axis of the spindle 3 so that the diamond dresses a substantially flat edge a, b, or c, d, Fig. 7, as the case may be, of a grinding-wheel 13. At the end of a rocking movement when the plungers are free of the apertures the bracket 4 can swivel about the spindle 5, the plunger 7 moving in an arcuate groove 8 in the plate 11 and the plunger 6 moving on the surface of the plate, movement being limited by engagement of the plunger 7 with the ends of the arcuate groove 8; the diamond thus dressing a radiused part b, c of the grinding-wheel 13. With the device shown in Fig. 5, the complete dressing operation is carried out automatically. The movements of a rocker arm 21 and a swivel bracket 4<SP>1</SP> are again controlled by a control plate 11<SP>1</SP> and two plungers (not shown), as above described ; a rocking spindle 3<SP>1</SP> in this case being geared to a spindle 5<SP>1</SP> about which the bracket 4<SP>1</SP> can turn, so that a continuous rotation of the spindle 5<SP>1</SP> by an electric motor 15 will first rotate the arm 21, then swivel the bracket 4<SP>1</SP> to radius the grinding-wheel, then rock the arm 2<SP>1</SP> again. The diamond holder, motor 15, &c. are mounted on a casting 37 pivoted at 20 on a grinder head 21 on which a grinding-wheel 13<SP>1</SP> is supported; an arm 19 of the casting 37 is pivoted to a block 23 vertically slidable in a slideway 39 rigid with a stationary saddle 34 of the grinding machine. The grinding-wheel carriage 21 is automatically fed towards the work to compensate for wear of the wheel by cam mechanism 24, 25, 26, pawl and ratchet 28, 29 and a screw 32 bolted to the carriage 21 and screwing in a bush 33 rigid with the saddle 34. The diamond is fed down towards the wheel an amount equal to the movement of the wheel towards the work as a consequence of the movement of the pivot 20 and of the casting 37 about the pivots 20 and 23. The motor 15 may be operated by a suitable timing electric relay. The apparatus may be operated manually. According to the Provisional Specification the diamond holder may be mounted to perform a sliding movement to dress a flat face of a grinding-wheel.