| 摘要 |
<p>1,071,650. Filling and emptying tanks. PARKER - HANNIFIN CORPORATION. Sept. 8, 1965 [Sept. 30, 1964], No. 38371/65. Heading B8T. [Also in Divisions F2 and G3] A valve arrangement for filling and discharging a tank (1), Fig. 1 (not shown), comprises a main closure member (40), Fig. 2 (not shown), defining a chamber (35) having restricted communication with the inlet via an annular passage surrounding a varying diameter rod (38) extending through the main closure member. Two pilot orifices (36, 37) constitute outlets from the chamber, these orifices cooperating with pilot valves (18, 19) normally unseated under the action of the pressure generated by jet level sensors (14, 15), in pipes (16, 17), the sensors being supplied via a pipe (8) from a manifold (6) provided with an inlet (5) and an outlet (7). To fill the tank (1), an interlock arm (33) is moved to allow a nozzle (4) to be coupled to the inlet (5) and to connect a source (31) of air pressure via valves (34, 30) to a vent valve (26) to open the latter. When the liquid level immerses the first sensor (14), the pilot orifice (36) is closed and the valve closure member (40) moves towards its closed position to a point determined by an enlargement (46) of the rod (38), the enlargement serving to restrict the entry of liquid into the chamber (35) to create a pressure balance across the valve. When the liquid level immerses the second sensor (15), the pilot orifice (37) is closed and the main valve member (40) closes. The interlock arm (33) is then returned to the position shown and the valve (34) exhausts a cylinder (23) to close the vent valve (26). To empty the tank, the outlet (7) is opened and (a) valve (28) is used to open the vent valve (26). On opening a valve (53), air from the source (31) passes, via the valves (32, 28) and pipes (51, 52) to a space (54) where it raises a piston (48) connected to the rod (38), the latter having a pin (47) which engages the valve closure member (40) to unseat the latter. One of the sensors (14, 15) may be omitted, the one remaining serving to close the main valve member (40).</p> |
