GB262047A - Improvements in and relating to the grinding and polishing of knife blades - Google Patents

Abstract

262,047. Siepmann, M., Siepmann, E., and Siepmann, E., (trading as Siepmann, & Co., E.). Nov. 24, 1925, [Convention date]. Cutting-edges, shaping and treating.-In a machine for grinding and polishing knives, the blade is reciprocated longitudinally across the grinding &c. disc and after each reciprocation is rocked through a portion of its transverse curvature; the machine is stopped automatically on completion of grinding &c. On a frame 1 is a slide 2 carrying an electric motor 4 driving a grinding or polishing disc 5, the slide being moved up to the work, against springs 6, by a rope 7 and a. pedal 8. The knife is mounted on a support 14 rockable on pointed screws 15 in a stirrup 13 adjustably carried by a plate 12, which is adjustable transversely on a slide 18. The slide is reciprocated on a cross-slide 20 by a lever 22, which is oscillated by the engagement with a slot therein of a crank block 23. The block is adjustable, to vary the throw, on a slide 30 mounted on a hollow shaft 26 driven, through worm gearing and a friction clutch 31 from the motor 4; a shaft 25 within the shaft 26 serves, by means of bevel and screw gearing, to adjust the block 23. In order to rock the knife after each reciprocation of the slide 18, a bar 52 thereon strikes a lever 45, which carries a pawl 46 engaging a ratchet wheel 47 driving a shaft 44. On the shaft is a pinion 43 engaging a rack 42 on a plunger 38 pressed upwards by a spring 40 and carrying a rail 37 engaging a bar 36 secured to the support 14; the plunger is thus lowered at each reciprocation, causing a small angular motion of the knife. In order to stop the machine after completion of polishing a knife, a cam disc 48 having a rise 59 is mounted loosely on the shaft 44 the disc having therein a slot in which is a pin carried by the ratchet-wheel. When the pin engages the end of the slot the cam is moved to lift the pawl 46 out of action, and further lowering of the plunger 38 moves levers 55, 56 to remove a latch 60 and release the pedal 8, when the grinding-wheel is withdrawn by the springs 6. The machine is started, after resetting, by depression of the pedal, which is again locked by the latch 60, the rail 37 being restored to its initial position by operation of a lever 62 which turns the disc 48. a cam 63 thereon lifting a pawl 53 and allowing the spring 40 to lift the plunger 38.