GB189816322A - Improvements in Pumping Engines. - Google Patents

Abstract

16,322. Newton, H. E., [Worthington, C. C.]. July 26. Pump valves and valve gear.-To positively close the valves as the plunger reaches the end of its stroke, the fluid pressure is applied to them under the control of valve mechanism actuated by a moving part of the pump. In the case of a duplex pump, each valve is connected to a piston working in a cylinder the upper end of which is connected alternately with a pressure supply such as the force main, and to exhaust. The connections are made by two valve mechanisms, of one of which Fig. 8 is a section. In the position shown, pressure water is being admitted by the port 5, the port in the rotary valve t, and the pipes 24, 27, to the controlling-cylinder of a delivery and suction valve respectively, while the cylinders of the other delivery and suction valve are connected by the port 7 and pipes, not shown, to the exhaust. In a modification, Fig. 10, the passages between the delivery chambers and the delivery main are controlled by valves u operated by a piston 37, which is acted on by fluid pressure controlled by a valve w. In a modification, applied to another type of pump, the suction-valve stem 106, Fig. 15, is provided with differential pistons 107, 107<a>, of which the former has the greater area, while the area of the latter is not greater than that of the suction valve seat. The space between the pistons 107, 107<a> is always under the delivery pressure, while the top of the piston 107 is alternately exposed by means of the valve 142, to the delivery pressure to accelerate the closing of the valve at the end of the stroke of the main plunger, and to the suction to allow the valve to open. The delivery valve may be similarly actuated. A slight modification of this construction is described. In another modification, Fig. 17, the suction and delivery valves A<3>, A<4> are provided with plungers g, g<4>, projecting into a chamber B<3> where, by means of the valve C<3> and appropriate passages, they are exposed to the delivery and suction pressure alternately. The valves A<3>, A<4>, C<3> may be contained in an independent casing which is connected at any convenient point to the pump. Slight modifications, applied to other types of pump, are described.