GB772737A - Improvements in or relating to knitting machines - Google Patents

Abstract

772,737. Knitting-machines. COTTON, Ltd., W. April 28, 1955 [May 1, 1954], No. 12700/54. Class 74 (2). An electrical circuit controlling the electric motor of a straight-bar machine, has switches 3, 4, 5 associated with the racking mechanism for the narrowing points or selvedge stops. Another switch 9 is associated with the narrowing frame 26 and is normally held open by the frame when it is in its raised inoperative position. Assuming that the narrowing points are correctly aligned with the needles, the switches 3, 4, 5 which are controlled by the indexing mechanism 10 through levers 12 are closed and upon operating a power rod to start the machine, switches 2 and 1 are closed in turn such that current flows from line A through switches 3, 4, 5, normally closed switches 6, 7, 8, and switches 2, 1. From the switch 1 the current passes through press-button stop and overload switch M to energize contactor coil K which causes contactor G to close to enable current to pass to the motor. Simultaneously, retaining switch HJ is closed to maintain the coil K energized and to retain the contactor G closed. the power rod being returned slightly to open switch 1. Prior to narrowing or selvedge stop adjustment the narrowing frame 26 is lowered, thereby closing switch 9 and retaining the circuit closed whilst the subsequent narrowing and selvedge stop adjustments are made during which time the switches 3, 4, 5 are momentarily opened. If, however, the narrowing mechanism or selvedge stops are incorrectly positioned, one or more of the switches 3, 4, 5 remains open such that upon the narrowing frame 26 returning to its raised inoperative position and opening its switch 9, the circuit becomes broken and the coil K de-energized. This action releases contactor G and breaks the supply to the motor such that the machine is stopped.