Diaphragm pumps
AssigneeHarben System Limited
InventorBernard E. Hart
Life of this patent
Estimating the term…
Abstract
A diaphragm pump comprises a body defining a chamber in which a diaphragm is arranged to divide the chamber into a drive chamber and a pump chamber. The pump chamber has an inlet and an outlet for fluid to be pumped, each of the inlet and outlet being provided with a one-way valve. The drive chamber has an inlet for driving fluid and the inlet is provided with a valve which is open under normal operating conditions of the pump. The valve is arranged so that, if a high pressure persists in the pump chamber when the pressure in the drive chamber is relieved causing the diaphragm to expand, the diaphragm will contact the movable valve member of the valve to move it to a position closing the inlet opening so that the drive chamber is isolated from the drive fluid pressure variations while the abnormal pressure subsists in the pump chamber.
Claims10
A pump comprising a body defining a chamber, a diaphragm in said chamber separating said chamber into a drive chamber and a pump chamber, said pump chamber being provided with an inlet and an outlet for fluid to be pumped, one-way valve means mounted in each of said inlet and said outlet, said drive chamber having an inlet for driving fluid which is under pressure and on which the pressure is relieved alternately, said inlet being associated with a valve for closing said inlet, said valve including a valve member movable between an open position and a closed position closing said inlet, said valve member being in its open position under normal operating conditions of said pump and being arranged to be contacted by said diaphragm if a high pressure subsists in said pump chamber when the pressure in said drive chamber is relieved to move said valve member to its closed position, and means responsive to movement of said valve member to its closed position for supplying driving fluid to an exhaust outlet to relieve the pressure on said valve member for so long as said valve member remains in its closed position.
A pump comprising a body defining a chamber, a diaphragm in said chamber separating said chamber into a drive chamber and a pump chamber, said pump chamber being provided with an inlet and an outlet for fluid to be pumped, one-way valve means mounted in each of said inlet and said outlet, said drive chamber having an inlet for driving fluid which is under pressure and on which the pressure is relieved and a valve in said drive chamber inlet comprising a valve member movable between an open position and a closed position closing said inlet, said valve member being in its open position under normal operating conditions and being arranged to be contacted by said diaphragm if high pressure subsists in said pump chamber when the pressure in said drive chamber is relieved, so as to move said valve member to its closed position, wherein said valve member has the general shape of a cup with a closed base and a lateral wall, said closed base facing said diaphragm, opening means being provided in said lateral wall through which drive fluid will flow when said valve member is in its open position.
Dependencies are inferred from the claim text.