Improvements in Machines for Grinding Shears, Scissors, Tableknives, Pocket-knives and the like.

摘要

22,387. Walker, H. W. Nov. 12. Wheel apparatus. - A machine for grinding shears, scissors, knives, &c. comprises a frame 1 having mounted thereon an adjustable abrasive ring 4 running in a trough 5, and a slide 7 on which is mounted a reciprocatory carriage 8. Pivoted at 9a to the carriage is a table 9 having a work-holder 10 secured thereto, the table being adapted to be moved towards and away from the abrasive wheel, about the pivot, by a cam 18 pivoted on the carriage and operated at the ends of the stroke by adjustable stops 21, 22. In the slide is mounted a continuously revolving screw 12 with which is adapted to engage a half-nut 16 mounted on the carriage and actuated by a lever 17 projecting through a slot in the slide and in line with adjustable stops 19, 20; the screw is driven through a longitudinally movable shaft 13, a worm and worm-wheel 14; and bevel-gears 15. The slide 7 is pivoted at one end on the stud 27 on which are mounted the bevel-wheel 15 and the worm-wheel 14, and the stud may be clamped in any desired position along a slot 25 in the machine frame; if the stud is set to the right along the slot, a concave surface will be ground in the article under treatment, and if set to the left along the slot, a convex surface will be ground. The front end of the slide, when its pivoted end has been set in the required position along the slot, is clamped by a screw 29 adapted to engage any of a number of holes 30 in the machine frame. In operation, after setting the slide according to the surface required on the work, the carriage is pushed in one direction by the operator by means of a lever 23 and a link 24 until the cam 18, striking the stop 22, forces the table towards the grinding-wheel, the half-nut being simultaneously engaged with the screw by the lever 17, which comes into contact with the stop 20. The return or grinding stroke of the carriage is then made by power until the cam and the lever strike the stops 21, 19 respectively, thus allowing a spring 26 to move the table from the grinding-wheel and also stopping the carriage. The hand stroke may be assisted by balance weights; a magnetic work-holder may be used.