Single piston double valve pump - has two valves connected to opposite ends of tee with branch connected to piston

摘要

A pump of very simple construction has two valves (1, 2) each with a valve member which is lifted from its seating by the flow of liquid through it, with a Tee connection (3) between them, with the branch of the Tee connected to a cylinder (6) inside which a simple piston (4) is raised and lowered by an operating lever (7). One side of this arrangement is connected to the suction pipe (12) fitted with a filter (13) and the other side is connected to a simple stop valve (15) at the discharge end. The piston carries sealing rings (5) and has also a flexible disc (8, 10) top and bottom secured by washers (9, 11). When the piston lifts, the first valve (1) opens and the second valve (2) closes so that liquid is drawn into the cylinder. The down strokes causes the second valve to open while the first valve closes so that liquid is forced towards the stop valve which also opens.