GB587270A - Grinding machine - Google Patents

Abstract

587,270. Grinding-machines. FOUQUET, E. Sept. 8, 1941, No. 11464. Convention date, Nov. 16, 1939. [Class 60] A grinding-machine comprises a multiple head to which a number of mutually inclined grinders can be fitted, the head being horizontally reciprocated rapidly at right angles to the work which is carried on a table capable of a rapid reciprocation at right angles to the head together with rising and lowering movements ; means are provided for measuring, and compensating for wear of, and for trueing, the grinding discs. The grinding head is mounted on a shaft 26, Fig. 3, driven by a belt and pulley 23 splinod thereto from a motor 1 adjustably mounted for tensioning the belt. The shaft 26 is carried in a tube 46 which can be reciprocated hydraulically by a piston 75 connected therewith and working in a fixed cylinder 76. The shaft has a conical end 35 for the reception of a grinding disc and drives, through a worm gear, a secondary shaft 37 to which a grinder may also be fitted ; the worm gear is enclosed in a casing 45 secured to the tube 46 which can be adjusted about its axis by means of a hand-operated worm 50; a pulley may be mounted on the shaft 37 and drive a smaller grinding wheel mounted on a spindle carried by the casing. Reciprocation of the tube 46 may also be effectect by a handoperated rack and pinion. The work 64 is mounted on a table 123 which is mounted on bearings comprising balls carried in grooves with end return grooves forming a closed cycle, and is hydraulically reciprocated horizontally in a similar manner to the tube 46 ; alternatively the table may be reciprocated by a hand or electrically-operated screw 153. The table is raised and lowered by a fixed screw 216 engaged by a nut operated through changespeed gearing arranged on shafts 187, 200, from an electric motor 180. The table may be manually raised by a hand wheel 218 and gearing 220, 221. To indicate wear on the grinding wheel, a feeler 230, Fig. 6, is provided which rests at the same level as the lowest part of the wheel and is formed in one with a toothed sector 233 in mesh with a gear 235 which drives a vertical rack 236 driving, by means of a small rack 238, a pinion 239 operating an indicator. A feeler 256 rests on a bar 257 partaking of the movement of the work table and drives a rack 259 carrying a gear 260 which rolls on the rack 236 ; the rotations of the gear 260 thus depend on the displacement of the feeler 256 which measures the depth of cut corrected by the displacement of the feeler 230 measuirng the wear of the grinder. Setting mechanism is provided whereby when the selected depth is cut a contact is closed and the upward motion of the table reversed. The grinders are dressed by a wheel 300 adjustable by a hand-operated worm 305, the setting of which can be observed against a scale. A periscope enables the grinding operation to be observed.