US3822388A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stirling engine power system and coupler
Assignee: MC DONALD DOUGLAS CORP
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Filing: 1973-03-26
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Granted: 1974-07-02
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Expires: 1993-03-26
Abstract
Abstract Stirling engine power system includes a displacer type Stirling engine producing an output of pressure pulses, load means to be driven by the output pulses, and a resonantly operated fluid coupler for coupling the output pulses suitably to the load means to drive the same. In one version of the power system, the load means is a piezoelectric generator driven to generate electrical output energy and the fluid coupler is a mercury-filled tube with a flexible diaphragm at each end to separate the mercury from working gas of the engine and hydraulic fluid of the generator. In another version of the power system, the load means is a hydraulic system including a hydraulic motor load and the fluid coupler is a hydraulic fluid-filled tube with a diaphragm at one end to separate the hydraulic fluid from the engine gas.
Inventors
- 👤 M White
- 👤 W Martini
- 👤 R Johnston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:39
CPC Classifications
H; H02; H02N; H02N2/00; H02N2/18; F; F02; F02G; F02G1/00; F02G1/04; F02G1/043; F02G1/0435; F16; F16H; F16H43/00; F16H43/02; F02G2250/00; F02G2250/27; F02G2258/00; F02G2258/10; F02G2270/00; F02G2270/50
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
168 words
A power system comprising; a Stirling engine including a displacer and a gaseous working fluid, said engine producing an output of pressure pulses; load means adapted to be driven by said pressure pulses; and a fluid coupler form of power member for coupling said pressure pulses to said load means to drive the same, said coupler including a tubular element of predetermined dimensions, a fluid of predetermined characteristics filling said tubular element and diaphragm means for separating said gaseous working fluid from said fluid filling said tubular element, and said tubular element filling fluid comprising a liquid column of relatively substantial predetermined inertial mass that provides in combination with characteristics of said engine and said load means a resonantly tuned spring-mass-damper system wherein a 90* phase lag is produced at resonant frequency between said displacer and said coupler liquid column, and high output energy can be directly obtained from a displacer type of Stirling engine operating a resonant power member without interposition of a mechanical crank and flywheel.
Claim 2
Dependent Claim
168 words
A power system comprising; a Stirling engine including a displacer and a gaseous working fluid, said engine producing an output of pressure pulses; load means adapted to be driven by said pressure pulses; and a fluid coupler form of power member for coupling said pressure pulses to said load means to drive the same, said coupler including a tubular element of predetermined dimensions, a fluid of predetermined characteristics filling said tubular element and diaphragm means for separating said gaseous working fluid from said fluid filling said tubular element, and said tubular element filling fluid comprising a liquid column of relatively substantial predetermined inertial mass that provides in combination with characteristics of said engine and said load means a resonantly tuned spring-mass-damper system wherein a 90* phase lag is produced at resonant frequency between said displacer and said coupler liquid column, and high output energy can be directly obtained from a displacer type of Stirling engine operating a resonant power member without interposition of a mechanical crank and flywheel.
Claim 3
Dependent Claim
35 words
The invention as defined in claim 1 wherein said load means includes a piezoelectric generator, and said coupler matches generator requirements with engine capabilities through inertial storage and delivery of energy by said liquid column.
Claim 4
Dependent Claim
35 words
The invention as defined in claim 1 wherein said load means includes a hydraulic system, and said liquid column includes a portion of hydraulic fluid which is used in said coupler and said hydraulic system.
Claim 5
Dependent Claim
49 words
The invention as defined in claim 1 wherein said tubular element includes necked-down end portions providing an intermediate portion having a throat area less than those of said end portions, to produce the operational effect of a much larger liquid mass than is actually present in said tubular element.
Claim 6
Dependent Claim
102 words
The invention as defined in claim 2 wherein said piezoelectric generator comprises a housing, a stack of piezoceramic discs contained in said housing and a piston adapted to be positioned against one end of said stack to compress the same in response to said pressure pulses, and said coupler matches generator requirements with engine capabilities through inertial storage and delivery of energy wherein said liquid column stores excess energy as kinetic energy during the first halves of the engine expansion and compression strokes and delivers said stored energy during the second halves of said expansion and compression strokes to complete the same.
Claim 7
Dependent Claim
55 words
For use in a power system, a fluid coupler comprising: a tubular element of predetermined length and size, said tubular element including necked-down end portions to provide an intermediate portion having a throat area less than those of said end portions; and a diaphragm closing off one of said end portions of said tubular element.
Claim 8
Dependent Claim
55 words
For use in a power system, a fluid coupler comprising: a tubular element of predetermined length and size, said tubular element including necked-down end portions to provide an intermediate portion having a throat area less than those of said end portions; and a diaphragm closing off one of said end portions of said tubular element.
Claim 9
Dependent Claim
21 words
The invention as defined in claim 6 further comprising another diaphragm closing off the other end portion of said tubular element.
Claim 10
Dependent Claim
22 words
The invention as defined in claim 6 further comprising a perforated backup plate mounted adjacent to said diaphragm to limit its travel.
Claim 11
Dependent Claim
34 words
The invention as defined in claim 8 further comprising an overpressure relief accumulator operatively mounted at the diaphragm end of said tubular element to protect said diaphragm from overpressurization when against said backup plate.
Claim 12
Dependent Claim
33 words
The invention as defined in claim 6 wherein said tubular element further includes longitudinally tapering diffuser portions respectively connecting said end portions to corresponding ends of said intermediate portion to minimize flow losses.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-07-01 | 1977-12-31 | 1978-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-01 | 1981-12-31 | 1982-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-01 | 1985-12-31 | 1986-07-02 | $7700.00 | Window Closed / Lapsed |