US4539001A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tensioning device for belt or the like
Assignee: Toyota Motor Corp
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Filing: 1983-12-30
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Granted: 1985-09-03
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Expires: 2003-12-30
Abstract
Abstract A hydraulic autotensioner of a sealed type is used to give tension to a belt or a chain. The hydraulic autotensioner includes a body member having a large diameter oil chamber, a plunger having a small diameter oil chamber and a small passage, a piston whose head extends outside the body member and a spring for biasing the plunger.
Inventors
- 👤 Yoshio Okabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:02
CPC Classifications
F; F16; F16H; F16H7/00; F16H7/08; F16H7/0829; F16H7/0836; F16H7/0848; F16H2007/0802; F16H2007/0806; F16H2007/0812; F16H2007/0859; F16H2007/0889; F16H2007/0891
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
123 words
A hydraulic autotensioner of a sealed type comprising: a body member defining a large diameter oil chamber; a plunger sealingly inserted in a movable manner in said body member, said plunger having a small diameter oil chamber formed in the center thereof and a small passage which communicates said large and small diameter oil chambers; a piston sealingly inserted in said plunger in a movable manner, said piston having a head extending outside of said body member, said piston head having an end face defining a press face; a spring in said body member for biasing said plunger in the direction of said large diameter oil chamber; and a snap ring arranged at an opening of said body member and engaging said spring.
Claim 2
Dependent Claim
123 words
A hydraulic autotensioner of a sealed type comprising: a body member defining a large diameter oil chamber; a plunger sealingly inserted in a movable manner in said body member, said plunger having a small diameter oil chamber formed in the center thereof and a small passage which communicates said large and small diameter oil chambers; a piston sealingly inserted in said plunger in a movable manner, said piston having a head extending outside of said body member, said piston head having an end face defining a press face; a spring in said body member for biasing said plunger in the direction of said large diameter oil chamber; and a snap ring arranged at an opening of said body member and engaging said spring.
Claim 3
Dependent Claim
30 words
A hydraulic autotensioner of a sealed type according to claim 1 including a second spring in said small diameter oil chamber for biasing said piston outside of said body member.
Claim 4
Dependent Claim
32 words
A hydraulic autotensioner of a sealed type according to claim 1 including a check valve at the bottom of said small diameter oil chamber to control opening and closing of said passage.
Claim 5
Dependent Claim
24 words
The hydraulic autotensioner of a sealed type according to claim 1 in combination with a belt, wherein said press face forcibly contacts said belt.
Claim 6
Dependent Claim
24 words
The hydraulic autotensioner of a sealed type according to claim 1 in combination with a chain, wherein said press face forcibly contacts said chain.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |