US4798563A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-contained type automatic belt tensioner
Assignee: Toyota Motor Corp
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Filing: 1987-12-08
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Granted: 1989-01-17
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Expires: 2007-12-08
Abstract
Abstract A self-contained type automatic belt tensioner adjusts a tension of an engine timing belt for automobiles. The tensioner comprises a body, a plunger slidably mounted in the body, a reservoir chamber located in the plunger, a pressure chamber disposed between the plunger and a closed wall of the body, a rod member fixed to the plunger, a bellows shaped elastic diaphragm located in the reservoir chamber with one end thereof being fixed to the rod member and the other end being fixed to the body, a check valve allowing a fluid flow only from the reservoir chamber to the pressure chamber, and a return spring interposed between the plunger and the closed wall of the body so as to bias said plunger in the direction of the rod member.
Inventors
- 👤 Yoshio Okabe
- 👤 Yukimori Kobayashi
- 👤 Makoto Ishikawa
- 👤 Tamotsu Kamiya
- 👤 Tomiaki Atsumi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 12:13
CPC Classifications
F; F16; F16H; F16H7/00; F16H7/08; F16H7/10; F16H7/12; F16H7/1209; F16H7/1236; F16H7/1254; F16H7/1281; F16H2007/0802; F16H2007/0812; F16H7/0848; F16H2007/0859
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
184 words
A self-contained type automatic belt tensioner for automobiles comprising: a body having an axially extending blind bore therein with an opening at one end, a closed wall at the other end; a plunger slidably mounted in said blind bore of said body; a reservoir chamber located in said plunger; a pressure chamber disposed between said plunger and said closed wall of said body; a rod member fixed at one end thereof to said plunger and protruding at the other end thereof from said opening of said body; a bellows shaped elastic diaphragm located in said reservoir chamber with one end thereof being fixed to said rod member and the other end being fixed to said body; a fluid passage connecting said reservoir chamber and said pressure chamber with each other; a check valve disposed in said fluid passage so as to allow a fluid flow only from said reservoir chamber to said pressure chamber; and a return spring interposed between said plunger and said closed wall of said body so as to bias said plunger in the direction of said opening of said body.
Claim 2
Dependent Claim
184 words
A self-contained type automatic belt tensioner for automobiles comprising: a body having an axially extending blind bore therein with an opening at one end, a closed wall at the other end; a plunger slidably mounted in said blind bore of said body; a reservoir chamber located in said plunger; a pressure chamber disposed between said plunger and said closed wall of said body; a rod member fixed at one end thereof to said plunger and protruding at the other end thereof from said opening of said body; a bellows shaped elastic diaphragm located in said reservoir chamber with one end thereof being fixed to said rod member and the other end being fixed to said body; a fluid passage connecting said reservoir chamber and said pressure chamber with each other; a check valve disposed in said fluid passage so as to allow a fluid flow only from said reservoir chamber to said pressure chamber; and a return spring interposed between said plunger and said closed wall of said body so as to bias said plunger in the direction of said opening of said body.
Claim 3
Dependent Claim
43 words
A self-contained type automatic belt tensioner according to claim 1, wherein said one end of said diaphragm is fixed to said rod member through a seal member and said other end of said diaphragm is fixed to said body through a seal member.
Claim 4
Dependent Claim
28 words
A self-contained type automatic belt tensioner according to claim 2, wherein said both ends of said diaphragm are prevented from moving by means of a stopper member, respectively.
Claim 5
Dependent Claim
32 words
A self-contained type automatic belt tensioner according to claim 1, wherein a stopper member is secured to said body to prevent said plunger from moving in the direction of said reservoir chamber.
Claim 6
Dependent Claim
20 words
A self-contained type automatic belt tensioner according to claim 1, wherein a fluid passage is formed in said rod member.
Claim 7
Dependent Claim
33 words
A self-contained type automatic belt tensioner according to claim 1, wherein a rotation stopper member is fixed at both ends thereof to said body so as to prevent said rod member from rotating.
Claim 8
Dependent Claim
25 words
A self-contained type automatic belt tensioner according to claim 1, wherein said check valve comprises a ball member and a spring supported by a retainer.
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) | 1992-01-17 | 1992-07-18 | 1993-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-01-17 | 1996-07-18 | 1997-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-01-17 | 2000-07-18 | 2001-01-17 | $7700.00 | Window Closed / Lapsed |