US5222878A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic reciprocating pump
Assignee: Nitto Kohki Co Ltd
•
Filing: 1992-01-29
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Granted: 1993-06-29
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Expires: 2012-01-29
Abstract
Abstract An electromagnetic reciprocating pump comprising of a closed-type casing provided with a cylinder in front thereof, a main shaft as least the front end of which is fixed to the casing, a piston having a piston head in front thereof, which piston is slidably fitted over the outer periphery of the main shaft to reciprocate, and coaxially supporting an armature, a spring disposed between the piston and the casing for biasing the piston in one direction, an electromagnet fixed to the casing so as to attract the armature in the opposite direction against the biasing force of the spring, suction ports and suction valves for sucking a fluid into a pressure chamber defined by the cylinder and the piston head, and a discharge port and a discharge valve for discharging the pressurized fluid from the pressure chamber.
Inventors
- 👤 Toshio Osada
- 👤 Tamotsu Mori
- 👤 Masaaki Tanabe
- 👤 Toshio Mikiya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:07
CPC Classifications
F; F04; F04B; F04B17/00; F04B17/03; F04B17/04; F04B53/00; F04B53/08; F04B17/046
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
221 words
An electromagnetic reciprocating pump comprising: a closed-type casing provided with a cylinder in the front end thereof, a main shaft, the front end of which is fixed to and supported on the front wall of said cylinder, and which main shaft is disposed so that the central axis thereof matches that of said cylinder, a piston having a piston head in the front end thereof, fitted over the outer peripheral surface of said main shaft so that said piston head reciprocates in said cylinder, and having an armature fixed and held thereon, a spring disposed between said piston and casing for biasing said piston in one direction, an electromagnet fixed within said casing for attracting said piston and armature in the opposite direction against the biasing force of said spring, a pressure chamber defined by said cylinder and piston head, and a suction port and a suction valve in one of said cylinder and piston head and a discharge port and a discharge valve provided in the other of said cylinder and piston head, wherein said main shaft is a hollow cylindrical body having both ends opened, and a fluid flows in a path of the hollow portion of said main shaft, a space between said piston and casing, said suction port, suction valve, pressure chamber, discharge port and discharge valve.
Claim 2
Dependent Claim
221 words
An electromagnetic reciprocating pump comprising: a closed-type casing provided with a cylinder in the front end thereof, a main shaft, the front end of which is fixed to and supported on the front wall of said cylinder, and which main shaft is disposed so that the central axis thereof matches that of said cylinder, a piston having a piston head in the front end thereof, fitted over the outer peripheral surface of said main shaft so that said piston head reciprocates in said cylinder, and having an armature fixed and held thereon, a spring disposed between said piston and casing for biasing said piston in one direction, an electromagnet fixed within said casing for attracting said piston and armature in the opposite direction against the biasing force of said spring, a pressure chamber defined by said cylinder and piston head, and a suction port and a suction valve in one of said cylinder and piston head and a discharge port and a discharge valve provided in the other of said cylinder and piston head, wherein said main shaft is a hollow cylindrical body having both ends opened, and a fluid flows in a path of the hollow portion of said main shaft, a space between said piston and casing, said suction port, suction valve, pressure chamber, discharge port and discharge valve.
Claim 3
Dependent Claim
25 words
An electromagnetic reciprocating pump as set forth in claim 1 wherein a rear end of said main shaft is unsupported relative to said casing end.
Claim 4
Dependent Claim
28 words
An electromagnetic reciprocating pump as set forth in claim 1 wherein a rear end of said main shaft is supported on a rear end wall of said casing.
Claim 5
Dependent Claim
42 words
An electromagnetic reciprocating pump as set forth in claim 3 wherein said main shaft, said front casing and rear casing are made of electrically conductive materials, an electrical insulating material is interposed on at least one of the joint surfaces of them.
Claim 6
Dependent Claim
54 words
An electromagnetic reciprocating pump as set forth in claim 1 wherein the fluid is sucked into the pressure chamber through the hollow portion of said main shaft, the space between the piston and casing, and the suction port and suction valve, and the pressurized fluid is discharged through the discharge port and discharge valve.
Claim 7
Dependent Claim
27 words
An electromagnetic reciprocating pump as set forth in claim 1 wherein cooling fins are formed on the inner surface of the hollow portion of said main shaft.
Claim 8
Dependent Claim
26 words
An electromagnetic reciprocating pump as set forth in claim 1 wherein sliding bearings are interposed between the outer periphery of said main shaft and said piston.
Claim 9
Dependent Claim
31 words
An electromagnetic reciprocating pump as set forth in claim 1 wherein sliding bearings are interposed between the outer peripheral surface of said piston head and the inner surface of said cylinder.
Claim 10
Dependent Claim
51 words
An electromagnetic reciprocating pump as set forth in claim 1 wherein said electromagnet consists of a plurality of magnetic poles which are radially fixed within said casing so as to be opposed to said armature with a predetermined gap therebetween, and coils wound around at least every other said magnetic poles.
Claim 11
Dependent Claim
49 words
An electromagnetic reciprocating pump as set forth in claim 7 wherein the number of the magnetic poles is an even number equal to four or greater, and any two magnetic poles of them are paired and disposed on a straight line passing through the center axis of the armature.
Claim 12
Dependent Claim
24 words
An electromagnetic reciprocating pump as set forth in claim 9 wherein at least one coil is wound around the magnetic pole in conical shape.
References Cited (Backward Citations)
US3542495A
Cited
US3384021A
Cited
US4261689A
Cited
US4416594A
Cited
JPS5747437A
Cited
US4787823A
Cited
US4867656A
Cited
US4854833A
Cited
US4966533A
Cited
US5104299A
Cited
US5073095A
Cited
US5100304A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-06-28 | 1996-12-28 | 1997-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-28 | 2000-12-28 | 2001-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-28 | 2004-12-28 | 2005-06-29 | $7700.00 | Window Closed / Lapsed |