Patent GB-1046945-A (GB)
Title: Improvements in and relating to skinning knives
IPC: A22B5/16
Filed: 1963-07-23
Abstract: 1,046,945. Flaying-apparatus. F. KNOLL. July 23, 1963 [July 24, 1962], No. 29106/63. Heading B4B. [Also in Division A2] A skinning knife for flaying carcasses has a motor-actuated, reciprocating blade 3 which is guided between two side guards 14a, 14b of an adjustable and removable blade protector, so that points on the cutting edge of the reciprocating blade execute oscillations, substantially in one plane, in relation to teeth 15 provided on the adjacent operative edges of the side guards. The blade is secured in a holder 2 attached, as by a bolt 2a, to a resilient spindle 1, which is reciprocated longitudinally by a pneumatic motor-(not shown) located in a hand grip 16. The blade protector also comprises a plate 14, to which the side guards are attached. A rocking link 8 is pivoted, at 7, to a bracket 5 secured to the blade. The link 8 is also pivoted to a leafspring 11 by means of a pivot shaft 9 in a journal 10, held in the curled forward end of the leaf-spring. The latter is clamped to a bracket 13 secured to the housing 16 by a screw 30, which passes through a threaded hole in the plate 14. A dowel pin 12 on the leaf spring is received in a hole 20 in the bracket 13, which has an oblique face or recess 19, against or in which the curled end of the leaf-spring 11 is received. If desired, the blade 3 may be guided by another rocking link 8a, Fig. 3b (not shown). A plate 28 engages collars 29 above the knurled heads of the screw 30 and another screw 31 passing similarly through the plate 14. The screw 31 has a pointed or hemispherical end 32, which is received in a conical or hemispherical depression 33 in a carriage 34 slidable on the bracket 13. The carriage 34 has an oblique face 35 and a slot in its rear portion, which engages a groove 37 in a knurled screw 36 threaded through a hole in a bracket 21 secured to the housing 16. The carriage 34 can be traversed along the bracket 13 by turning the screw 36. A tensioned spring 18 is hooked to the plate 28 and the bracket 21. A screw 23 is threaded into the bracket 13 to clamp a square-headed, tubular sleeve 24 thereto. A lever 26 is pivoted, by pins 25, to the head of this sleeve and has two cams 27, at its forward end, which, in the locking position of the lever, as shown, engage the plate 28. The lever, when in the locking position, may prevent rotation of the screw 36. When the lever 26 is swung from its locking position, the cams 27 recede from the plate 28 and the spring 18 then draws the blade protector rearwardly along the oblique face 35 to expose the cutting edge of the blade, e.g. so that it can be sharpened. By turning the screw 30 and/or the screw 31, the blade protector can be raised or lowered relative to the blade 3 and/or tilted about the fulcrum 32. By turning the screw 36, the blade protector can be moved to a desired position along the blade 3. To release the blade, the screw 23 is unscrewed thus disengaging the lever 26, the spring 18 is unhooked, the blade protector is removed, bolt 2a is unscrewed and the leaf-spring 11 is released. The blade can then be removed and a new blade inserted. The blade may be attached to the spindle 1 in the following alternative manner. A stepped bolt 38 carrying a sleeve 39, Figs. 4 and 5 (not shown), is inserted into a hole in the blade and the blade, bolt and sleeve are then riveted together. A journal 40 is mounted on the bolt and sleeve on each side of the blade. The ends of the bolt and sleeve are received in holes in the limbs of a U-shaped spring 41, whose bridge portion 49 is received in a slot 42 in the blade. The blade holder 43, e.g. of nylon, has, at its rear end a slotted hub 44, which is secured to the spindle 1 by a clip 45 having a clamping screw 46. The forward end of the blade holder constitutes a cam 48 and is provided with a trough 47, in which the journals 40 are received. In the working position of the blade, the cam 48 engages the under surface of the bridge portion 49 and retains the journals 40 in the trough 47. By turning the blade until the cam 48 disengages the bridge portion 49, the blade 3 can be detached from the blade holder 43. Preferably, the distance between two consecutive teeth 15 should not exceed 8 mm., the gliding angle, i.e. the angle between the line joining two consecutive teeth apices and the tangent to the recess curve between them; should not exceed 60 degrees, the thickness of the blade should not exceed 0À7 mm., the width of the slot k between the side guards 14a and 14b should not exceed 0À9 mm., and the difference between the width of the slot k and the thickness of the blade should not exceed 0À45 mm.