| 摘要 |
<p>1,260,351. Valves. RAUFOSS AMMUNISJONSFABRIKKER A.S. 13 Jan., 1969 [11 Jan., 1968], No. 1992/69. Heading F2V. [Also in Division G3] An automatic control valve for an agricultural sprinkler system has a main closure member 11 on the end of a stepped piston for co-operation with a seat 5 between an inlet 3 and an outlet 8. An axial bore 14 extends through the piston to communicate fluid pressure to the large diameter end of the piston and also allow fluid to flow to an outlet 24 past a pilot valve 22 which is held closed by a bucket assembly 27, 28. Evaporation of fluid in the bucket 27 allows the assembly to tilt over, partially opening pilot valve 22 and permitting fluid to flow from outlet 24 into bucket 28. The bucket assembly then rapidly tilts to completely open the pilot valve and also the main valve. The pilot valve closes when bucket 27 is sufficiently full, the majority of the fluid in bucket 27 draining out when in the position shown, lip 34 retaining sufficient to hold the pilot valve closed. In another embodiment a passage extends between the larger diameter bore of the valve housing and the outlet and a solenoid, float or manually-operated pilot valve therein acts as a shut-off valve.</p> |
