Positive displacement inductive pump
View Patent ↗A positive displacement inductive pump includes a central piston formed of a ferromagnetic material having non-ferromagnetic end pistons that extend from each of its opposite ends. Stationary end walls are mounted to opposite ends of a housing and are centrally bored. First and second inductive coils are alternately energized, causing the central piston and the end pistons to conjointly reciprocate within an axial bore and the end wall central bores, respectively. First and second check valves are positioned outboard of each end wall and allow valve-controlled ingress and egress of material into and out of the axial and central bores. The relative diameters of the central piston and the end pistons are changed to control the relationship between the magnetic force applied and the output pressure for a given volume of fluid.
1. A positive displacement inductive pump, comprising:
a housing formed of a ferromagnetic material;
said housing including an axial bore formed in said housing;
first and second stationary end walls secured to opposite ends of said housing, said first end and second end walls having a magnetic field;
a central bore formed in each of said end walls,
said axial bore and said central bores of said end walls having a common longitudinal axis of symmetry;
said central bores of said end walls forming a displacement chamber within said first and second end walls;
a central piston formed of a ferromagnetic material disposed in the axial bore;
non-ferromagnetic end pistons extending from opposite ends of said central piston, said end pistons and said central piston having a common longitudinal axis of symmetry;
each end piston being slideably received within an associated end wall central bore;
each end piston having a length greater than the depth of its associated end wall central bore, thereby preventing the central piston from contacting or residing within each of the end walls;
first and second inductive coils disposed in the housing around the axial bore between the end walls and coaxial with the axial bore; and
each of said coils being alternately energized to produce respective first and second magnetic fields causing the central piston to reciprocate within the axial bore and causing each end piston to simultaneously reciprocate within said associated end wall central bore, respectively.
2. The positive displacement inductive pump of claim 1 , further comprising:
first and second check valve assemblies respectively attached to an outboard end of said end walls and in communication with said central bores of said end walls to alternately open and close said central bores to allow ingress and egress of a fluidic material into and out of the central bores as said central piston and said end pistons reciprocate conjointly with one another.
3. The positive displacement inductive pump of claim 1 , further comprising:
a seal secured to an outer surface of each end piston to form a seal between each end piston outer surface and the inner surface of its associated central bore.
4. The positive displacement inductive pump of claim 1 , further comprising:
said end pistons and the central bores within which they are slideably received having diameters that are less than a diameter of said central piston.
5. The positive displacement inductive pump of claim 1 , further comprising:
said central piston, said end pistons, and said end walls each include a predetermined material that does not react with the fluidic material being pumped by said pump.
6. The positive displacement inductive pump of claim 5 , wherein said predetermined material is ceramic.
7. The positive displacement inductive pump of claim 1 , further comprising:
said housing having an inner compartment formed of a ferromagnetic material, said inner compartment defining said axial bore.