Patent GB-533296-A (GB)
Title: Improvements in or relating to a method of knitting fabrics of and kind and a straight bar knitting machine for carrying out said method
IPC: D04B11/28
Filed: 1939-08-08
Abstract: 533,296. Knitting. LAMBACH, H. Aug. 8, 1939, No. 22910. Convention date, March 6. [Class 74 (ii)] A partly finished article is automatically transferred to the needles of a straight-bar machine, fabric is knitted on to the transferred piece and the article thus finished is automatically pressed off the needles. The invention is described in connection with the knitting of stockings in which heels 284 are knitted on to the high heels of transferred blanks 512. Alternatively an elastic border may be transferred to the needles of a glove knitting machine, or in the manufacture or underwear warp or other knitted borders can be transferred to the needles of the machine for knitting the remainder 'of the article. The device for transferring the partly finished fabrics comprises a turn-table 496 rotatable in operative position about a vertical axis 500 and mounted so as to swing also about a shaft 504 into and out of operative position. The turn-table may have six sections, each having extensions 510 into which an operative can place a transfer bar 508. The table 496 is rotated by a ratchet wheel 532 to which it is coupled by pins 568 engaging in slots 566 in the wheel 532. The wheel is rotated by a pawl 530 pivoted at one end of a lever 536. The lever 536 is coupled to a push rod 538 which is actuated at each narrowing movement of the cam shaft 54, so that at each narrowing, the wheel 532 is advanced one tooth. A stop pawl 518 is provided for locking the table in the correct position for delivering the partly finished article to the machine, and is actuated by a stop on the main pattern chain to release the table when it is to be rotated to bring the next transfer bar into position. To permit of lost motion so that the ratchet wheel 532 is not rotated further than is required to bring the next bar into position, the lever 536 works between collars 540, 542 on the push rod 538 and a spring 544 is arranged on the push rod between one collar 542 and the lever 536. The transfer bar 508 with the partly finished article held upon the quills 624 thereof is taken from the turn-table and placed over the needles of the machine by gripping latches 590 pivoted at the front ends of bell crank levers 584 mounted on a supporting frame 578. The latches 590 are held closed so as to grip a bar 508 by springs, and are opened to take the bar from the table by the engagement of studs 596 on the latches with a guiding member 598. The supporting frame 578 is loosely mounted upon the needle bar 466, and is rotated about it by gears 406 meshing with gear segments 606 upon a shaft 600. A lever 608 is keyed to the shaft 600 and carries a roller 614 co-operating with either a cam 126 so that the shaft 600 and segments 606 are oscillated. The position of the frame 578 and levers 584 when the bar is about to be taken from the table is shown in Fig. 4; the position when the quills are above the needles is shown in Fig. 10. To permit the finished article to be pressed off, additional stop levers 270, 271 operable upon the thread carrier spindle 312, and thread clamping and cutting devices 678, 680, Fig. 17, are provided. The stop levers 270, 271 have adjustable pins 398, 399, Fig. 1, which upon the completion of the article or ravel courses knitted on to the article are permitted to fall into notches 396 not shown) in sleeves 392, 394 arranged on the thread carrier spindle 312, and allow the levers 270, 271 to drop into the path of the thread carriers to stop them. The thread clamp 678 and the knife 680 each have a hooked end and are slidably arranged in tracks in a block 668 adjustably arranged on the sinker head. The end of the knife is attached by a link 686 to a bell-crank lever 692 carrying a roller 720 engaging a cam 62. The clamp 678 is coupled to the knife 680 by a projection 694 and spring 696, which spring is arranged between the projection 694 and a clamping piece 682 by which the knife is secured to the link 686. The arrangement permits of a lost motion such that when a thread has been gripped by the clamp 678 and the cutter 680 is moved by its cam 62 away from the needle bar, the knife can be operated while the clamp under pressure of the spring 696 grips the thread. In addition to the motor (not shown) for normal high speed operation of the main cam shaft 54, a motor 44 for driving the cam shaft 54 slowly for the period of transference of the partly finished article to the needles is provided and a switch is operated by stops on the main pattern chain to change over from one motor drive to the other. Means are provided for bringing the knock-over bits during the transfer operation into a position lower than their lowest working position. A hydraulic shock absorber 576 is connected to the main cam shaft 54 for damping shocks during its axial narrowing movements. The invention is described in connection with a machine for topping one stocking blank only at a time, but may be applied to multi-section machines.