Patent GB-1306041-A (GB)
IPC: B24B41/06
Filed: 1971-05-24
Abstract: 1306041 Grinding TOYODA KOKI KK 24 May 1971 [30 May 1970] 16711/71 Heading B3D A grinding machine comprises a bed 1, Fig. 1, a grinding-wheel 5, a headstock 13, a pair of shoes 42, 43 mounted on the bed for supporting a workpiece W in a working station during a grinding operation, one, 40, of the shoes being fixedly mounted adjacent the grinding-wheel, and the other, 43, being mounted adjacent the grinding wheel for movement towards and away from said one shoe so as to discharge a workpiece downwardly from the shoes, means 16 on the headstock for rotating the workpiece, and means for transferring the workpiece into and out of the working station in co-operation with the movement of the shoe 43. The grinding wheel 3 is belt-driven from a motor 6 on a wheelhead 2 slidable on the bed towards and away from the working station by a feed screw driven by a fluid actuator. The wheel is trued by a cutter 5a rotated by a motor 5b and slidable on a base 5c, and wear of the wheel is compensated by a device 4. A body 12 is fixed to the bed and carries the headstock 13 and a work support 14. The headstock consists of a spindle 15, Fig. 5, having a magnetic driver 16 and a packing plate 17, the spindle being driven by an electric motor 18. The workpiece is supported at the working station by the shoes 40, 43, shoe 40 being adjustably mounted on a plate 41, Fig. 2, secured to the work support 14. The workpieces are fed to the working station from a shoot 21 secured to a plate 20 mounted on the body 12. The lower workpieces are retained in a vertical part of the shoot by a plate 23, and a spring-pressed roller 25 holds the lowermost workpiece in a stop-plate 24. The shoe 43 is mounted on a swivel plate 44 which when moved to retract the shoe permits the finished workpiece to drop to a discharge shoot 60, an arm 61 ensuring that the workpiece is discharged. At the same time, an arm 30 having a plug 31 engaging the bore in the lowermost workpiece in the shoot 21 moves that workpiece to the working station. The arm 61 is secured to a shaft 62, Fig. 3, arm 30 is secured to a shaft 32, and the swivel plate 44 of shoe 40 is secured to a shaft 50. The shafts 62, 32 and 50 are equidistant from a driving shaft 74 which during each loading and unloading operation, is rotated through one revolution by a rack-andpinion drive 134 driven by an hydraulic actuator, accurate rotation being determined by engagement of a plunger with a notched disc 121 on the shaft 24, the drive being conveyed to the shaft by a one-way clutch. The driving shaft is connected to the shafts 50, 62 by a cam 78 and to the shaft 32 by cam 77 which effect controlled rotation of those shafts. Face cams 29, 80 on the driving shaft effect axial movement of the shafts 32, 62. In operation, when the workpiece is ground to size as determined by a sizing device 160, the wheelhead is retracted and the hydraulic actuator operated to rotate the driving shaft 74. The cam 78 on the shaft causes the shaft 50 to rotate and retract the shoe 43 so that the finished workpiece can fall to the discharge shoot 66. At the same time, shaft 62 is rotated so that the arm 61 is swung downwardly to positively unload the workpiece. The cam 77 rotates shaft 32 so that arm 30 with its plug 31 is swung to carry the new workpiece from the shoot 21 to the working station whereupon the shoe 43 is advanced by further rotation of shaft 32 to engage the workpiece, the rate of advance of the shoe being reduced towards its final movement so that it does not push the workpiece into the grinding wheel. Thereafter, the cams 79, 80 on the driving shaft cause axial movement of the shafts 32, 62 so that the plug 31 is disengaged from the workpiece and the arms can be swung back to their original angular positions, the shafts also moving axially back to their original positions to engage the plug 31 with the next workpiece and place the arm 61 above the workpiece to be ground. The sizing device 160, Fig. 16, consists of a lever 161 which is mounted on a cross-spring 166 and at one end has an anvil 161a for engaging the workpiece, and at the other end has a core movable within energized windings 163. The device is mounted in a casing 162 adjustable along an inclined guideway 165a on a pedestal 165 secured to the base 11.