GB861970A - Ball cock - Google Patents

Abstract

861,970. Fluid-pressure servomotor-control systems. DOYLE, O. K. Aug. 24, 1957, No. 26768/57. Class 135. In a liquid-level float-controlled valve, Fig. 3, the pressure in a chamber 53, having a flexible wall 42 which is seatable on the end of an inlet pipe 10, is controlled by a rod 60 having a flattened portion co-operating with an opening 55 in the upper side of the chamber, so that when the rod 60 is lowered, Fig. 2, not shown, the chamber communicates with exhaust and an opening 46 in the wall 42 leading to the inlet pipe is closed by the lower end of the rod 60 and inlet pressure acting on the lower side of the wall 42 flexes it upwards to open the valve. On raising the rod 60, Fig. 3, the opening to exhaust is closed and that to the inlet pipe 10 opened and inlet pressure acting over a larger area of the wall 42 in the chamber 53 than on on the outside closes the valve. Fig. 1 shows the valve contained in a casing 14 attached to the top of the standpipe 10 mounted in the bottom of a tank and actuated by an openended annular float 20 surrounding the standpipe and mounted on a float arm 17 which engages a loop 77 on the upper end of the rod GO and is pivoted at 76 in a shell 66 which forms the top of the valve casing and by means of a slot 80 acts as a guide for the loop 77 to constrain the rod 60 to move vertically. The outlet from the casing is by means of four depressions 33 which form cylindrical passages, 29 only shown, at the lower end of the casing that are so dimensioned as to induce streamline flow and permit silent operation of the device. In Figs. 6, 7, not shown, the lower end of the rod is formed as a hemisphere and the slot 80 is widened to permit angular movement of the rod to open the bore 55.