Patent GB-783379-A (GB)
Title: Improvements in straight-bar knitting machines
IPC: D04B11/00
Filed: 1955-09-28
Abstract: 783,379. Knitting-machines. ETABLISSEMENTS A. GILLIER. Sept. 28, 1955 [Oct. 20, 1954], No. 27664/55. Class 74 (2). If, in a straight-bar machine, there is failure in the normal entry of a lever 17 in to a groove 18, to lock in its " knitting cycle " position a plunger 5, projected for cam-shaft shogging and narrowing, a safety member 21, 21a or 61 enters the groove, to prevent reprojection of the plunger (with the attendant second dipping of the narrowing frame) and to cause operation of a machine-stopping switch : a spring 7 projects the plunger, under control of a restoring cam 13 acting on a roller 14, so that a roller 4 on the plunger may co-operate with a camshaft-shogging face cam 3. In the embodiment of Fig. 2, when the camshaft is shogged, the cam 13 comes opposite a roller 35 of diameter greater than that of roller 14. Consequently, when the plunger 5 is returned by the cam 13 at the end of the narrowing cycle, it is first pushed beyond its rest position so that the nose of the safety member 21, which is wider than that of lever 17, will be urged by a spring 25 into the groove 18, unless lever 17 has itself entered the groove, in which latter case a roller 32 carried by the lever 17 opposes this movement of the safety member. When the cam-shaft returns to its normal knitting position, the roller 14 will again be opposite the cam 13 and the plunger 5 will have moved forward to its normal rest position by an amount sufficient to ensure that the wider nose of the member 21 shall not drop into the groove, but shall rest on the plunger surface when the lever 17 is raised to initiate the next narrowing operation. In the embodiment of Figs. 6 and 7, the noses of the lever 17 and the safety member 21a are of the same width and the roller 35 is omitted, the width of the roller 14 being correspondingly increased. The sleeve 6, in which the plunger 5 slides, houses a stop 51 normally projected by a spring 54; and, when the lever 17 is raised at the beginning of a narrowing cycle, a lug 50 on the member 21a falls on to the stop, to prevent the nose of the member 21a entering the groove 18. The plunger 5 is now advanced by its spring 7 and, as it reaches the end of its stroke, a screw 33 which it carries, pushes in the stop 51, the end of the member 21a falls on to the plunger 5 and the lug 50 registers with the end face of the stop 51 to prevent its projection. If the machine runs normally, the locking lever 17 falls into the groove at the end of the narrowing cycle, and the roller 32 rocks the member 21a counterclockwise, to release the stop 51. If, however, the lever 17 fails to enter the groove, after the plunger 5 has been pushed back, the member 21a falls into the groove. In the embodiment of Figs. 10 and 11 (not shown), the safety finger 61 is normally held inactive by a solenoid 63, the circuit being completed through a switch 65 (closed when the locking lever 17 is in its groove) and a switch 66, in parallel with the switch 65 (and closed when the cam-shaft 1 is in knitting position). Thus, when all parts are positioned for knitting, both switches are closed. When the lever 17 is raised to prepare a narrowing cycle, switch 65 opens, the safety finger 61 remaining inoperative. When the cam-shaft is shogged for narrowing and the switch 66 also opens, the finger falls on to the plunger surface. When the narrowing operation has been completed, the plunger returns to its rest position and, since the cam-shaft has not yet resumed its knitting-cycle position, failure of lever 17 to fall into its groove and so close switch 65, will leave finger 61 free to drop into the groove. To permit a plurality of narrowing movements (e.g. in forming lace clocks and picot work) the safety member 21 may be rendered inoperative by a button on a pattern chain, acting through a cable 29, or from the shaft 40, Fig. 12, through a lever 41 and a cable 28 or, manually, by engaging the hooked end of a rod 46 connected to the lever 41, over a hook 47 on the machine frame. In Fig. 10, a switch 64 in parallel with the other two switches, may be operated by buttons on a chain 72 activated by the chain 70 of the machine.