Patent GB-474743-A (GB)
Title: Improvements in and relating to grinding, polishing and like machines
IPC: B24B19/00
Filed: 1936-04-02
Abstract: 474,743. Grinding. ERN, C. F. April 2, 1936, No. 9782. Convention date, April 2, 1935. [Class 60] A machine for grinding and polishing articles of different cross-sectional forms, particularly razors and other cutlery, comprises grinding- wheels 1, 2 mounted on pivotal levers 4, 5, disposed on either side of a central plane in which the work is supported, the length of each lever and the distance of its pivot 9 from the central plane being so chosen that alteration in the diameter of the grinding-wheels can be compensated, without substantially affecting the cross-sectional size and form of the finished article, solely by pivotal adjustment of the levers, without simultaneous adjustment of the article being necessary. The manner in which these dimensions are determined to obtain this result is explained with the aid of diagrams. The machine shown comprises grinding-wheels 1, 2 carried on levers 4, 5 the pivotal points 9 of which are adjustable towards and from the central plane, a support 37 for the work 30, together with means for pivoting the levers to and from one another and for moving the support 37 in the central plane towards and away from the throat formed between the grinding-wheels, the combination of these movements determining the form of the surface produced. By suitable adjustments hollow-ground, convex, or flat-surfaced forms may be produced, and the edges may be sharpened. In the machine shown, the pivots 9 of the levers 4, 5 are carried by slides 10 adjustable to and from the central plane by pinions 27 engaging racks on them. They may be adjusted simultaneously and equally, or separately and unequally for producing articles of asymmetrical section. During grinding the levers are swung to and from the central plane by means of links 11, 12 pivoted to them and to a member 15 vertically reciprocated by a rod 24 which is operated by a grooved cam 20 in which a follower 23 on the rod engages. At the same time the work-holder 37 is reciprocated vertically by means of a cam 46. The shafts carrying the cams 20, 46 are both driven through gearing from the main driving- shaft. The mean height of the member 15 may be adjusted by a hand wheel 14 operating through bevel gears a screwed shaft 18, thus enabling the angular relation of the levers 4, 5 to be varied for a given setting of the pivots 9. A similar adjustment operating a screwed rod 43 enables the mean height of the work-support 37 to be varied. During grinding the work is horizontally , reciprocated through the grinding-throat by a lever 32 operated through a connecting-rod 35 from a crank-pin adjustably mounted in a slot 34 on a disc 33 on the main shaft to allow the stroke to be varied in length. The lever 32 operates a horizontal slide 36 carrying the work-support 37, the head of the lever engaging in a vertical slideway 361 formed in the slide in order to permit the vertical movement of the latter. The work-holder carrying the work may be mounted in succession on a number of machines performing successive operations such as rough grinding, polishing, fine polishing, and sharpening, and may be transferred automatically from one to another by a conveyer device.