摘要 |
<p>A servo-mechanism controls the left-right angle of a spout so as to maintain the difference between a signal from a wagon-machine angle sensor and a signal from a spout angle sensor within a certain range, by actuation of spout-right and spout-left relays (110 and 114) which provide signals on corresponding lines (68 and 66) to a hydraulic system driving the spout. A manually-operable switch can also be used to energise line 68 or line 66 for moving the spout within the substantial dead-band normally existing, for ensuring even wagon filling. When the wagon-machine angle is large a circuit (195) provides a signal (line 91) to increase the servo gain. To ensure re-alignment of the spour when the wagon-machine angle becomes small again, a timer (198) delays reversion to the low servo gain. A circuit (300) detects actuation of the manual switch and then applies a signal to the timer to reduce the delay. </p> |