Patent GB-669748-A (GB)
Title: A straight-bar knitting machine and a method for operating same
IPC: D04B11/00
Filed: 1949-02-01
Abstract: 669,748. Knitting-machines. LAMBACH, F. Feb. 1, 1949 [Feb. 3, 1948], No. 2730/49. Class 74 (ii). A straight-bar machine has loop transferring means which at predetermined intervals are automatically swung step-by-step into and out of co-operating relation with the needles. In the embodiment described, the loop transferring means comprises picot bars 298, one for each section of the machine, carried on a shaft 296 which is rotated by ratchet means to bring the picot points 300 into and out of an active position. The ratchet pawls, 374, 380, are carried on a member 378 oscillated through linkage 438, 440, 450, 456 by a positive cam 428 pivoted on the pivot shaft 256 of the narrowing machine. The picot bars and operating linkage are carried on the narrowing machine and up and down movement of the latter causes no movement of the link 438 when a portion of the track of the cam 428 concentric with the shaft 256 coincides with the roller of the link 438. Movement of the cam 428 to bring a portion 430, eccentric with the shaft, into engagement with the roller causes oscillation of the link 438. The cam 428 is pivoted to effect this, by linkage 412, 418, 422, Fig. 5, operated from the main cam-shaft 38. The link 418 is secured to a pivoted block 410 carrying a member 406 which is swung into or out of engagement with a projection 416 on the link 412 by linkage 396, 398, 400, 402, 404, Figs. 1 and 5, operated from the main pattern chain 40. When the members 416, 406 are in contact, the cam 428 is shifted to cause operation of the picot bar racking means. A bluff 364 controlling the picot-bar racking means is operated by a cam 302, Fig. 5, connected by linkage 304, 308 to cam and linkage means 314, 322, 332, 346, 358 similar to that operating the member 378. The bluff 364 has a projection 373, Fig. 16, which is engaged by a portion 388 of one of the bars 270, carrying normal narrowing combs 280, so that when these are in the knitting-field, the bluff 364 may not be moved to permit racking of the picot bars into active position. When the pattern chain shifts the linkage 396-402 above, to cause movement of the picot bars 298, the link 396 operates a bellcrank 490 to cause locking in an inactive position of a lever 62, Fig. 1, to prevent racking of the yarn carrier stop-nuts 146 and narrowing combs 280. The stop nuts and narrowing combs may be operated in the manner described in Specification 655,451. The narrowing machine is raised and lowered by cams 236, Fig. 1, so shaped that the picot points in their active position are first lowered to take loops, then raised part of the maximum amplitude of swing of the narrowing machine. At this position the member 378 is turned on the shaft 296 so that an adjustable projection 472, Fig. 11A, carried thereon contacts a fixed stud 474 whereby the shaft 296 and picot points are shifted one needle space. The loops are returned to the needles and the points varied to their maximum height. The invention may be used in connection with lace points and known lace point axial shifting means may be used in lieu of the projection 472 and stud 474. The bars 298 may be held in any position by an index wheel 466 and finger 462, Fig. 11A. Specification 660,004 also is referred to.