Patent US4413657A successfully refreshed from Google Patents.
US4413657A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust pipe with vibration damping
Assignee: Nippon Steel Corp
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Filing: 1981-09-08
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Granted: 1983-11-08
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Expires: 2001-09-08
Abstract
Abstract From the exhaust tube of automobiles the power source sounds and travelling sounds are radiated as noises. A heat-resistant intermediate layer is disposed partly around the inner tube of dual metal tubing and achieves decreases in the radiated noise from the exhaust pipe due to the vibration damping of the inner and outer tubes.
Inventors
- 👤 Takesada Sasaki
- 👤 Hiroshi Endo
- 👤 Yoshimasa Zama
- 👤 Masahiko Shiraishi
- 👤 Yosinari Miura
- 👤 Masayuki Yamaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 17:55
CPC Classifications
F; F16; F16L; F16L55/00; F16L55/02; F16L9/00; F16L9/21; B; B21; B21C; B21C37/00; B21C37/06; B21C37/15; B21C37/154; F01; F01N; F01N13/00; F01N13/14; F01N13/141; F01N13/08
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
130 words
An exhaust pipe for discharging hot gas from an internal combustion engine comprising: an inner tube and an outer tube, the inner surface of the outer tube and the outer surface of the inner tube defining an annular region therebetween; a heat-resistant intermediate layer filled between said inner tube and said outer tube over the entire distance of said annular region as seen in the longitudinal direction of said inner and outer tubes and having a thickness of from about 0.1 to 0.5 mm, said heat-resistant intermediate layer comprising a continuous length of heat-resistant material, said length of said heat resistant material being from about 40% to 70% of the circumference of the annular region; and a gap left in the annular clearance where said heat-resistant material is not filled.
Claim 2
Dependent Claim
130 words
An exhaust pipe for discharging hot gas from an internal combustion engine comprising: an inner tube and an outer tube, the inner surface of the outer tube and the outer surface of the inner tube defining an annular region therebetween; a heat-resistant intermediate layer filled between said inner tube and said outer tube over the entire distance of said annular region as seen in the longitudinal direction of said inner and outer tubes and having a thickness of from about 0.1 to 0.5 mm, said heat-resistant intermediate layer comprising a continuous length of heat-resistant material, said length of said heat resistant material being from about 40% to 70% of the circumference of the annular region; and a gap left in the annular clearance where said heat-resistant material is not filled.
Claim 3
Dependent Claim
21 words
An exhaust pipe according to claim 1, characterized in that said inner tube is nonconcentric with respect to said outer tube.
Claim 4
Dependent Claim
43 words
An exhaust pipe according to claim 2, characterized in that said inner tube is offset relative to said outer tube so that a portion of the outer surface of the inner tube contacts a portion of the inner surface of the outer tube.
Claim 5
Dependent Claim
24 words
An exhaust pipe according to claim 1, wherein said heat-resistant intermediate layer has heat resistance at a temperature of the exhaust gas of automobiles.
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) | 1986-11-07 | 1987-05-09 | 1987-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-07 | 1991-05-09 | 1991-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-07 | 1995-05-09 | 1995-11-08 | $7700.00 | Window Closed / Lapsed |