US4501302A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air gap pipe
Assignee: AP Parts Manufacturing Co
•
Filing: 1983-10-14
•
Granted: 1985-02-26
•
Expires: 2003-10-14
Abstract
Abstract An air gap pipe and a method for forming the same are provided. This air gap pipe includes a non-linear outer pipe and an inner pipe of identical configuration disposed concentrically within the outer pipe. The inner pipe is supported by resilient dimples in the outer pipe. The outer pipe is placed in a condition for receiving the inner pipe by longitudinally cutting the outer pipe in half with a pre-programmed plasma arc or laser cutting apparatus. The two halves of the outer pipe are secured together to provide vents, if necessary, for selective dissipation of heat.
Inventors
- 👤 Jon W. Harwood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:54
CPC Classifications
F; F01; F01N; F01N13/00; F01N13/18; F01N13/1888; F01N13/14; F01N13/141; F01N13/1838; F01N13/08; F01N2450/00; F01N2450/20; F01N2450/22; F01N2470/00; F01N2470/24
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
113 words
A non-linear air gap pipe for carrying heated vehicular exhausts, said air gap pipe comprising: an inner pipe bent into a selected non-linear configuration for carrying the vehicular exhaust gases; and an outer pipe concentrically disposed around the inner pipe with an air gap therebetween, said outer pipe including a plurality of resilient supports extending inwardly and contacting the inner pipe, said outer pipe being formed by first and second longitudinal halves with said first and second halves being joined together at selected locations along opposed longitudinal sides such that vents are defined between said selected locations, whereby said outer pipe and said vents control the flow of heat from said inner pipe.
Claim 2
Dependent Claim
113 words
A non-linear air gap pipe for carrying heated vehicular exhausts, said air gap pipe comprising: an inner pipe bent into a selected non-linear configuration for carrying the vehicular exhaust gases; and an outer pipe concentrically disposed around the inner pipe with an air gap therebetween, said outer pipe including a plurality of resilient supports extending inwardly and contacting the inner pipe, said outer pipe being formed by first and second longitudinal halves with said first and second halves being joined together at selected locations along opposed longitudinal sides such that vents are defined between said selected locations, whereby said outer pipe and said vents control the flow of heat from said inner pipe.
Claim 3
Dependent Claim
15 words
An air gap pipe as in claim 1 wherein the supports are inwardly extending dimples.
Claim 4
Dependent Claim
23 words
An air gap pipe as in claim 1 wherein the first and second halves of said outer pipe are joined by spot welding.
Claim 5
Dependent Claim
19 words
An air gap pipe as in claim 3 wherein the spot welds are between six and twelve inches apart.
Claim 6
Dependent Claim
22 words
An air gap pipe as in claim 1 wherein said vents are disposed only along one longitudinal side of said outer pipe.
References Cited (Backward Citations)
US236077A
Cited
US2370062A
Cited
US3457724A
Cited
US3645092A
Cited
US3884194A
Cited
US3908372A
Cited
US4031699A
Cited
US4185463A
Cited
DE2642995A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-26 | 1988-08-27 | 1989-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-26 | 1992-08-27 | 1993-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-26 | 1996-08-27 | 1997-02-26 | $7700.00 | Window Closed / Lapsed |