US4272064A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas spring
Assignee: Tokico Ltd
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Filing: 1979-08-02
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Granted: 1981-06-09
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Expires: 1999-08-02
Abstract
Abstract A gas spring comprises a cylindrical outer sheath having a stopper holding structure on the inner surface, a rod and piston unit slidably received in the outer sheath, a rod guide and a packing sealably fitted in the outer sheath, and a stopper freely received in the outer sheath for limiting the upward movement of the piston and having engaging structure on the outer surface to engage on the stopper holding structure to thereby hold the stopper in position in the outer sheath.
Inventors
- 👤 Teiji Katsumori
- 👤 Kunio Ishida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:14
CPC Classifications
F; F16; F16F; F16F9/00; F16F9/32; F16F9/58; F16F9/585; F16F9/02; F16F9/0209; F16F9/0218; F16F9/48; F16F9/49
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
240 words
In a gas spring comprising an outer sheath having a substantially uniform inner diameter (D) and an annular convex formed on the inner surface of said outer sheath, said annular convex having an inner diameter (d4), a piston-rod unit slidably received in said outer sheath, and a stopper received in said outer sheath and having a substantially uniform outer diameter (d1), said stopper having formed in the outer surface thereof an annular recess for engaging said annular convex and for thereby holding said stopper in position within said outer sheath, said annular recess having a bottom diameter (d2), the improvement wherein: said annular recess is formd in said outer surface of said stopper at a position intermediate upper and lower surfaces of said stopper; and said outer diameter (d1) of said stopper is greater than said bottom diameter (d2) of said annular recess and said inner diameter (d4) of said annular convex, but smaller than said inner diameter (D) of said outer sheath, whereby there is a clearance between said inner surface of said outer sheath and said outer surface of said stopper, and whereby when said annular recess of said stopper is not engaged with said annular convex of said outer sheath said stopper is freely movable within said outer sheath, such that said stopper may be easily inserted into said outer sheath without scratching said inner surface of said outer sheath or said outer surface of said stopper.
Claim 2
Dependent Claim
240 words
In a gas spring comprising an outer sheath having a substantially uniform inner diameter (D) and an annular convex formed on the inner surface of said outer sheath, said annular convex having an inner diameter (d4), a piston-rod unit slidably received in said outer sheath, and a stopper received in said outer sheath and having a substantially uniform outer diameter (d1), said stopper having formed in the outer surface thereof an annular recess for engaging said annular convex and for thereby holding said stopper in position within said outer sheath, said annular recess having a bottom diameter (d2), the improvement wherein: said annular recess is formd in said outer surface of said stopper at a position intermediate upper and lower surfaces of said stopper; and said outer diameter (d1) of said stopper is greater than said bottom diameter (d2) of said annular recess and said inner diameter (d4) of said annular convex, but smaller than said inner diameter (D) of said outer sheath, whereby there is a clearance between said inner surface of said outer sheath and said outer surface of said stopper, and whereby when said annular recess of said stopper is not engaged with said annular convex of said outer sheath said stopper is freely movable within said outer sheath, such that said stopper may be easily inserted into said outer sheath without scratching said inner surface of said outer sheath or said outer surface of said stopper.
Claim 3
Dependent Claim
27 words
The improvement claimed in claim 1, wherein said bottom diameter (d2) of said annular recess is substantially equal to said inner diameter (d4) of said annular convex.
Claim 4
Dependent Claim
68 words
The improvement claimed in claim 1, wherein said outer surface of said stopper is provided with a plurality of convex sectors, the diameter (d3) of said stopper at the areas of said convex sectors being greater than said inner diameter (d4) of said annular convex, said convex sectors being press-fitted in said inner surface of said outer sheath to hold said stopper in position in said outer sheath.
Claim 5
Dependent Claim
26 words
The improvement claimed in claim 3, wherein the relationship between d 1 , d 2 and d 3 is d 1 >d 3 >d 2 .
Claim 6
Dependent Claim
22 words
The improvement claimed in claims 1, 2, 3 or 4, wherein said stopper is formed of a somewhat resilient synthetic resin material.
References Cited (Backward Citations)
DE2331852A1
Cited
US4044866A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-08 | 1984-12-08 | 1985-06-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-08 | 1988-12-08 | 1989-06-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-08 | 1992-12-08 | 1993-06-09 | $7700.00 | Window Closed / Lapsed |