Patent EP0343774A2 successfully refreshed from Google Patents.
EP0343774A2
Expired / Lapsed
EP
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Stirling refrigerator with nonlinear braking spring
Assignee: Mitsubishi Electric Corp
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Filing: 1989-03-17
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Granted: —
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Expires: 2009-03-17
Abstract
Abstract A Stirling refrigerator has a cold-finger 2 in which a displacer 7 can reciprocate in accordance with changes in pressure inside the cold-finger which are produced by a compressor 1. A nonlinear spring 16 is connected between the displacer and the cold-finger in order to brake the movement of the displacer at the ends of its stroke. The nonlinear spring has a greater spring constant when it is deformed by the displacer being near either end of its stroke than when the nonlinear spring is in a neutral position.
Inventors
- 👤 Yoshio C/O Chuo Kenkyusho Of Mitsubishi Kazumoto
- 👤 Yoshiro C/O Chuo Kenkyusho Of Mitsubishi Furuishi
- 👤 Kazuo C/O Chuo Kenkyusho Mitsubishi Kashiwamura
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-31 23:40
CPC Classifications
F; F25; F25B; F25B9/00; F25B9/14; F16; F16F; F16F1/00; F16F1/02; F16F1/04; F16F1/08; F16F2228/00; F16F2228/06; F16F2228/066
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
185 words
A Stirling refrigerator comprising: a cold-finger (2) which contains a working gas and includes a displacer chamber (6) and a gas spring chamber (12) which is sealed off from said displacer chamber; a displacer (7) which is slidably disposed inside said displacer chamber so as to be able to reciprocate therein and perform a stroke and which divides said displacer chamber into a compression chamber (8) and an expansion chamber (9), said displacer having a piston element (11) thereon which extends into said gas spring chamber; and a compressor (1) which is connected to said compression chamber and periodically varies the pressure of the working gas inside said compression chamber; characterized in that a nonlinear spring (16) acts on said displacer (7) so as to be deformed as said displacer (7) reciprocates within said cold-finger (2), said nonlinear spring having a neutral position which it assumes when said displacer is between the ends of its stroke, the spring constant of said nonlinear spring being greater when said displacer is near either end of its stoke than when said nonlinear spring is in its neutral position.
Claim 2
Dependent Claim
185 words
A Stirling refrigerator comprising: a cold-finger (2) which contains a working gas and includes a displacer chamber (6) and a gas spring chamber (12) which is sealed off from said displacer chamber; a displacer (7) which is slidably disposed inside said displacer chamber so as to be able to reciprocate therein and perform a stroke and which divides said displacer chamber into a compression chamber (8) and an expansion chamber (9), said displacer having a piston element (11) thereon which extends into said gas spring chamber; and a compressor (1) which is connected to said compression chamber and periodically varies the pressure of the working gas inside said compression chamber; characterized in that a nonlinear spring (16) acts on said displacer (7) so as to be deformed as said displacer (7) reciprocates within said cold-finger (2), said nonlinear spring having a neutral position which it assumes when said displacer is between the ends of its stroke, the spring constant of said nonlinear spring being greater when said displacer is near either end of its stoke than when said nonlinear spring is in its neutral position.
Claim 3
Dependent Claim
25 words
A refrigerator as claimed in Claim 1, wherein said nonlinear spring is disposed inside said gas spring chamber and is connected to said piston element.
Claim 4
Dependent Claim
17 words
A refrigerator as claimed in Claim 1 or 2, wherein said nonlinear spring surrounds said piston element.
Claim 5
Dependent Claim
17 words
A refrigerator as claimed in Claim 1, wherein said nonlinear spring is disposed inside said displacer chamber.
Claim 6
Dependent Claim
42 words
A refrigerator as claimed in Claim 1, 2, 3 or 4 wherein said spring behaves in a linear manner in the vicinity of its neutral position and behaves in a nonlinear manner when said displacer is near either end of its stroke.
Claim 7
Dependent Claim
16 words
A refrigerator as claimed in any preceding Claim, wherein said nonlinear spring is an hourglass-shaped spring.
Claim 8
Dependent Claim
19 words
A refrigerator as claimed in any of Claims 1 to 5, wherein said nonlinear spring is a double-coil spring.
Claim 9
Dependent Claim
29 words
A refrigerator as claimed in any of Claims 1 to 5, wherein said nonlinear spring is a helical spring made from wire whose gauge varies over the length thereof.
Claim 10
Dependent Claim
11 words
A Stirling refrigerator substantially as described with reference to the drawings.
Claim 11
Dependent Claim
11 words
A Stirling refrigerator substantially as described with reference to the drawings.
References Cited (Backward Citations)
No citation records indexed.
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