Patent GB-444275-A (GB)
Title: Improvements in devices for sharpening knives of slicing machines
IPC: B24B3/46
Filed: 1934-12-11
Abstract: 444,275. Sharpening slicing-machine knives. BERKEL & PARNALL'S SLICING MACHINE MANUFACTURING CO., Ltd., Aden Road, Ponders End, Middlesex.-(Maatschappij van Berkel's Patent Naamlooze Vennootschap; 33, Boezemsingel, Rotterdam, Holland) Dec. 11, 1934, Nos. 35536/34 and 10063 /35. [Class 60] The circular knife of a slicing-machine is sharpened by a device which is freely pivoted about an axis substantially parallel to that of the knife so that it may be lowered into operative position, where it is held by the combined action of gravity and the forces due to the rotating knife. In the construction shown in Figs. 1, 2 and 3, grinding and burrremoving wheels 7, 8 are mounted on ballbearings in a casing 6 which is freely pivoted by a pin 14 to a sleeve 15 secured by a clamping- screw 18 to a rod 19 carried by a bracket 20 pivotally mounted on a pin 23 secured to the knife bracket 2. In the inoperative position of the sharpening device, it is turned about the pivot pin 23 so as to incline towards the left as it is seen in Fig. 2, the casing 6 and sharpening wheels carried by it lying to the left, and clear, of the knife 1. To bring the sharpener into the operative position shown, the casing 6 is raised by a handle 35 about the pivot 14 until a projection 28 carried by it clears an auxiliary knife guard 29. During this movement, the end of the spring-pressed spindle 11, Fig. 3, of the burr-removing wheel 8 rides up a cam 16, which causes axial movement of the spindle and carries the wheel 8 into position to engage the opposite face of the knife 1. The whole device is then turned about the pivot 23 to the position shown in Fig. 2, and the casing 6 is subsequently lowered about the pivot 14 until the wheels 7, 8 are in contact with the knife, the spindle 11 moving down the cam 16 so that it may be moved axially by the spring to bring the wheel 8 into contact with the outer face of the knife. The parts are arranged so that the resultant of the frictional forces between the knife 1 and the wheels 7, 8 exerts a downward turning movement on the casing 6 about the pivot 14, so that these forces augment the action of gravity in holding the sharpening wheels against the knife. The casing 6 may be weighted, or, when it lies below the axis of the knife 1, counterweighted to move it upwardly. The sharpener may be adjusted vertically on the rod 19 as the knife wears. Any other movement, for example, one about a vertical axis, may be substituted for that about the horizontal pivot pin 23 to move the sharpener to and from the plane of the knife. In a modification shown in Figs. 6 and 7, the casing 6 of the sharpener is carried by an arm 44 extending from a boss 45 freely pivoted on a boss 40 slidably but non-rotatably mounted on a rod 43 secured to the knife bracket. The cam 16 which operates, as in the previous construction, the spindle 11 of the burrremoving wheel is carried by the boss 40. As the sharpener is slid along the rod 43 it must be lifted so that a projection 48, Fig. 6, clears a collar 47 on a pin 46, thus preventing it from fouling the knife during movement from operative to inoperative position and vice versa.