| 摘要 |
Two signal generators respectively detect the passage of the shuttle between its boxes and along the sley, and the operation of the loom cyclic drive mechanism, the signals from the two generators being fed to a comparator which gives a constant output while the signals arrive alternately. When two like signals arrive in succession the comparator output changes and control is operated to arrest the sley. Specif., the comparator includes a bistable electronic circuit with transistors fed with pulses from respective magnetic pick-ups and magnets associated with the shuttle and sley, and the loom frame and crankshaft, the output of the comparator controlling a solenoid which in turn controls a clutch and brake mechanism in the drive to the sley. Specif., the solenoid releases a latch to allow a loom drive control member to be moved by spring-loading to a loom-inoperative position, from which it is re-settable manually, in which it releases the clutch and applies the brake. Shuttle faults are detected early in the loom cycle, giving adequate time for stopping the loom. |
