GB446477A - Sewing machine - Google Patents

Abstract

446,477. Sewing-machines. FAIRWEATHER, W. C., 65, Chancery Lane, London.- (Singer Manufacturing Co. ; Elizabeth, New Jersey, U.S.A.) Nov. 13, 1935, No. 31375. [Class 112] In machines in which the needle assists the feed dog in moving the superposed plies of work past the stitching point, the actuating eccentrics of the two feeds are concomitantly adjustable. The under-shaft 20, driven from the main shaft 9 by the belt 18, has a pair of bevel gears 22, 23 for actuating the loop takers. The work is advanced longitudinally of the work arm 3 by the four-motion feed dog 25 carried by the feed bar 30 carried in a bracket 31 in the feed arm 3 for rocking and endwise movements. The rocking movements for raising and lowering the dog are imparted by a fork 32 on the feed bar 30 embracing the feed lift eccentric 34 on the shaft 20. The endwise or feed advancing movements are imparted by a fork 36 on the feed bar which engages a block 37 embracing the feed-advance eccentric 38. This eccentric is adjustably secured on the shaft 20 to alter the feed length. To adjust it, the detent 40 on the cover 39 of the arm 3 is depressed against its spring to enter the stop notch 41 in the periphery of the adjusting member 42 associated with the eccentric 38, restraining this against rotation. Adjustment of the eccentricity of the eccentric 38 is thus made by turning the shaft 20, while the member 42 is stationary. A similar adjustment is then made to alter the length of the assisting needle feed. The needle bar 13 reciprocates in a gate 14 pivoted at 15 and vibrated in the direction of the main feed by a cranked part 43 of the arm 44 rocked by a member 45 forking an eccentric 47 on the main shaft 9. The eccentric 47 embraces an eccentric 48 which can be turned on the shaft to vary the eccentricity of the eccentric 47 and so vary the needle feed. The eccentric 47 has a flange 49 with a slot 50 entered by a block 51 carried by a pin 5 This pin is fixed to a driving disc 53 secured to the main shaft 9. The pin 52 extends through a slot 55 in a flange 49 of the adjusting eccentric 48. For adjusting the eccentricity of the eccentric 47, the flange 49 is provided with a circular groove 57 which affords a clearance recess for a friction plate 58 and the heads of screws which are threaded into the disc. The flange 56 of the member 48 is provided with a stop notch 61 to receive a detent manually operable to hold the adjusting member against rotation with the eccentric 47. This detent comprises the reduced end 63 of the plunger 62. To effect concomitant adjustment of the feed of both needle and dog, the plunger 62 is pushed inwards against its spring and rotated to prevent retraction. The detent 40 on the work arm is then depressed. The main shaft 9 is then turned through the required angle to effect the desired adjustments of the eccentrics 38 and 47. To'facilitate accurate adjustment, graduations 72 are made on the periphery of the driving disc 53. Specifications 253,002, [Class 112], and 435,360 are referred to.