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US3877841A Expired / Lapsed US ⏱️ 0.0 years remaining

Electromagnetic plunger pump

Assignee: Individual
•
Filing: 1973-10-31
•
Granted: 1975-04-15
•
Expires: 1993-10-31
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Abstract

Abstract An electromagnetic plunger pump which is capable of continuously controlling the discharge pressure at a predetermined level by effectively dealing with such factors as the heating of the electromagnetic plunger pump and a fluctuation of the input voltage which are unavoidable in practice, and is capable of making a smooth adjustment of the pressure even to a minute change in the discharge pressure, and also is capable of making a smooth and stable adjustment of the pressure even to a variation in the discharge pressure.

Inventors

  • 👤 Tadashi Nakamura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 07:48
CPC Classifications
F; F04; F04B; F04B49/00; F04B49/22; F04B49/24; F04B11/00; F04B11/0008; F04B11/0033; F04B17/00; F04B17/03; F04B17/04; F04B17/046

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 208 words
In a reciprocating electromaGnetic pump including a cylinder, a magnetic piston having a flow passage therethrough and having inlet and outlet ends and slidably mounted in the cylinder, said cylinder defining a pumping chamber surrounding the inlet end of said piston and receiving fluid therein, means for reciprocating the piston including an electromagnetic coil coaxial to said magnetic piston, a power source coupled to said electromagnetic piston for selective activation thereof, and a check valve mounted on the piston in the fluid flow-passage, the improvements which comprise a pump body having a passageway therein, one end of said passageway being a fluid inlet, a suction side check valve and a discharge side check valve positioned within said passageway and normally biased closed, said passageway communicating with said pumping chamber in the vicinity of said suction side check valve, whereby the suction stroke of said piston opens said suction side check valve and draws fluid into said passageway, said fluid forcing open said discharge side check valve, said pumping chamber also communicating with said passageway in the region of said discharge side check valve, fluid being drawn into said pumping chamber therefrom, and a relief valve means communicating with said pumping chamber and said passageway of said pump body.
Claim 2
Dependent Claim 208 words
In a reciprocating electromaGnetic pump including a cylinder, a magnetic piston having a flow passage therethrough and having inlet and outlet ends and slidably mounted in the cylinder, said cylinder defining a pumping chamber surrounding the inlet end of said piston and receiving fluid therein, means for reciprocating the piston including an electromagnetic coil coaxial to said magnetic piston, a power source coupled to said electromagnetic piston for selective activation thereof, and a check valve mounted on the piston in the fluid flow-passage, the improvements which comprise a pump body having a passageway therein, one end of said passageway being a fluid inlet, a suction side check valve and a discharge side check valve positioned within said passageway and normally biased closed, said passageway communicating with said pumping chamber in the vicinity of said suction side check valve, whereby the suction stroke of said piston opens said suction side check valve and draws fluid into said passageway, said fluid forcing open said discharge side check valve, said pumping chamber also communicating with said passageway in the region of said discharge side check valve, fluid being drawn into said pumping chamber therefrom, and a relief valve means communicating with said pumping chamber and said passageway of said pump body.
Claim 3
Dependent Claim 40 words
The device of claim 1 further comprising an accumulator mounted at a second end of said passageway of said pump body, said pumping chamber communicating with said passageway in the region intermediate said accumulator and said discharge side check valve.
Claim 4
Dependent Claim 90 words
The device of claim 1 wherein said relief valve means is comprised of a relief valve operatively seated over a nozzle, and wherein said check valve includes a fixed valve seat and a movable valve member of magnetic material cooperating with the seat to close said passage, said movable member being so positioned as to be drawn away from its seat by the attraction of the electromagnetic coil during operation of the pump to allow fluid flow, said check valve being positioned at the outlet end of said magnetic piston.
Claim 5
Dependent Claim 26 words
An electromagnetic plunger pump according to claim 3, in which said relief valve means is made of a flexible material such as rubber and synthetic resin.
Claim 6
Dependent Claim 19 words
An electromagnetic plunger pump according to claim 3, said relief valve forming a cavity provided with a tapered portion.
Claim 7
Dependent Claim 44 words
An electromagnetic plunger pump according to claim 1, in which a cap is provided on said relief valve, a spring is disposed between this cap and a thrust spring seat, and an adjusting screw thrustingly engaging with said thrust spring seat is also provided.

References Cited (Backward Citations)

US2828765A Cited
US3556684A Cited
US3601152A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-04-14 1978-10-14 1979-04-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-04-14 1982-10-14 1983-04-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-04-14 1986-10-14 1987-04-15 $7700.00 Window Closed / Lapsed

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