| 摘要 |
<p>1,177,056. Valves. CESSNA AIRCRAFT CO. 10 April, 1968 [15 May, 1967], No. 17341/68. Heading F2V. Initial movement of a spring-centred spool 25 from the neutral position shown allows flow from inlet 11 to a chamber 48, via spool passages 36-38 and casing passage 20, to cause pistons 44, 45 to move outwards to unseat load check valves 42, 43. Subsequent spool movement connects one motor port 14 or 15 to inlet 11 and the other to its respective exhaust port 12 or 13. When the spool is returned to neutral, chamber 48 is vented through spool passages 41, 39, 40 and the check valves close. Any leakage into passages 18, 23 leaks to drain through passages 57, 58 in pistons 44, 45 and passages 41, 39, 40. A detent 53 can engage in recess 54 to define a " float " position of the spool in which both motor ports are disconnected from the inlet and connected to exhaust. The check valves can also be unseated by depression of pin 59, and can alternatively be seated by a spring and motor port pressure. In Fig. 6 (not shown), the leakage into passages 18, 23 passes to drain directly through spool passage (41).</p> |
