Patent GB-168306-A (GB)
Title: Improvements in or relating to machines for cutting files or the like
IPC: B23D73/00
Filed: 1921-07-20
Abstract: 168,306. Durlach, H. Aug. 19, 1920, [Convention date]. File and rasp cutting. -In a file or rasp cutting machine having the blank mounted in a carriage 8 traversed automatically by a screw 7 and the chisel 11, Fig. 1, oscillated to cut at different angles, the guide 23 for the chisel holder 13 is mounted on a shaft 22 which is rotatably arranged in a rotating sleeve 36, Fig. 3, carrying templets 25, 34, 35 which regulate the angularity of the guides 23 &c., the strength of the blow and the drive of the carriage. The machine is driven bv a fast pulley 46, Fig. 3, on a shaft 48 which rotates a clutch 31<a>, Fig. 2, at a slow speed through worm and belt gear 49, 50 and a shaft 51 and a clutch 66, at a rapid rate in the reverse direction, through belt gear 61, 62, shaft 63, and bevel gear 65. A double cone feathered on a shaft 44 is moved, to engage one or other of the clutches 31<a>, 66 by a cam on a shaft 77 through linkwork 120, 120a, Fig. 3. The shaft 44 drives the screw 7 through bevel gear and shafts 41, 4a, 5 and drives the sleeve 36 through a shaft 38, Fig. 2, and worm gear 37. The chisel holder 13 is reciprocated by a cam 14, Fig. 1, driven by belt gear 67, 68, 69 from the shaft 48, and a spring 18, tensioned by a chain 19 which passes around a roller 91, Figs. 1 and 3, eccentric on a shaft 87<1>, on to a drum which can be rotated, to adjust the spring, by a hand-operated worm 20 and bv a lever 93 which carries the worm and engages the templet 34. During the advance of the blank beneath the chisel (1) the templet 25 acts through linkwork 26, 26<a>, adjustable at 118 and 28 to vary the angle of cut, the parts being balanced by weights 29 on a pulley 30 and a weight 31 connected thereto by a belt, and (2) the templet 34 varies the length of the chain and hence the force of the blows. Then the templet 35 acting through linkwork 75, 111, Fig. 2, operates a clutch to cause a constantly driven pulley 121 to give a definite rotary movement to its shaft 78 and, through gears 73<a>, Fig. 3, to a cam shaft 77. This by bevel gear 83, 86 and shafts 87, 87<1> relaxes the chain 19 and bv cams 17<c> &c. and linkwork 81, 119, 120 lifts the chisel holder 13 out of reach of the cam 14, raises a presser foot 17, Fig. 1, and reverses the clutches 31<a>, 66, thereby effecting a rapid return of the carriage 8 &c. The attendant replaces the cut file by a fresh blank and the cam 35 again actuates the shaft 77 which returns the parts 19, 13, 17, 31<a> and 66 to their original positions and the operations are repeated. The clutch of the pulley 121 may also be operated by a hand-lever 112 or wheel 113, Fig. 1, and the clutches 31<a>, 66 by a pedal 80. The chisel may also be lifted out of action by the pedal 79. At each blow of the chisel the feed of the blank is momentarily arrested by a brake 54, Fig. 3, which acts on a drum 53 on the shaft 51 and is operated, by a face cam 55, Cardan shaft 58, Fig. 3, and worm gear 59, from the shaft of the cam 14. The carriage 8 may be vertically adjusted, relative to the nut 94, Fig. 1, by slots and bolts 96 and may be automatically adjusted longitudinally, to obtain a fine cut near the point of the blank, by a rack and segment 98<x> operated by a roller 97 and adjustable stationary cam 98. The guides for the carriage are supported by a pivot 124 and a leg 9 sliding on a rail 10. The presser 17 can be angularly adjusted by a hand-operated worm 17b. The belt shifter 117, Fig. 3, for the main drive 46 is operated by a handle 116.