| 摘要 |
<p>A solenoid-operated fluid-flow control valve (11; 45) comprising a single solenoid coil (15; 53), the energisation of which controls the movement of first and second armatures (16 and 17; 56 and 57) which in turn control first and second respective valve means (20, 21, 23 and 27, 28; 70, 71 and 79, 80). The armatures are biassed away from the solenoid by respective springs (18 and 19; 58 and 59), one of which is weaker than the other. When the solenoid is energised by a constant current the armature (16; 56) with the weaker spring (18, 58) is attracted to the end of the solenoid and forms part of a magnetic circuit. This increases the magnetic flux at the other end of the solenoid, allowing the second armature (19; 57) to be drawn to the solenoid sequentially after, and subsequent to, the drawing-in the of the first armature. Particular anti-lock brake systems incorporating the valve are disclosed.</p> |
