Patent ID: 8152476

Claim:
A positive displacement pump comprising: at least one pumped media pumping chamber comprising at least one deformable hydraulic diaphragm, wherein said at least one pumping chamber is fluidly connected to a common pumped media inlet end and a common pumped media outlet end; inlet and outlet flow control valves in fluid connection with the inlet and outlet end of each said at least one pumping chamber; a working fluid drive cylinder assembly having first and second ends and containing a working fluid; a working fluid drive piston slidably situated within the working fluid drive cylinder between the first and second ends; at least one electromagnetic linear motor attached to the working fluid drive piston such that a linear reciprocating motion of said linear motor drives a reciprocating motion of said working fluid drive piston within said working fluid drive cylinder assembly; and at least one working fluid compression jacket enclosing at least a portion of said at least one pumping chamber wherein said at least one working fluid compression jacket contains a working fluid in fluid communication with said working fluid drive cylinder assembly such that a linear reciprocating motion of said working fluid drive piston driven by said at least one linear motor alternatingly applies a constrictive and an expansive force to said at least one deformable hydraulic diaphragm; and a non-transitory control module comprising a computer readable control program, wherein said linear reciprocating motion of said at least one linear motor is controlled electrically by said non-transitory control module according to said computer readable control program; wherein said control program comprises computer readable instructions to control the linear motor to produce a varying driving motion of the working fluid drive piston such that a substantially constant pumped media inlet pressure is maintained at the common pumped media inlet end.