US4004634A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automotive oil cooler
Assignee: Bank of Nova Scotia
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Filing: 1975-05-06
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Granted: 1977-01-25
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Expires: 1995-05-06
Abstract
Abstract Submerged oil cooler for automotive vehicles requires only two principal parts but can provide more heat transfer at a lower pressure drop than conventional oil coolers which utilize three principal parts. In a preferred embodiment, an outer tube having a plurality of longitudinal flutes which are periodically transversely indented is press fit over an inner tube having a helically finned outer surface. The tubes are sealed at their ends so as to define an extended annular flow channel for oil between the tubes, while permitting engine coolant in which the cooler is submerged to flow through the inner tube. A modified arrangement substitutes corrugated tube for the finned inner tube with a resulting cost saving in material but with a small increase in pressure drop and a small loss in heat transfer efficiency.
Inventors
- 👤 Edward P. Habdas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:13
CPC Classifications
F; F28; F28F; F28F9/00; F28F9/02; F28F9/0234; F28D; F28D7/00; F28D7/10; F28D7/106; F28F1/00; F28F1/10; F28F1/12; F28F1/34; F28F1/36
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
134 words
In a submerged oil cooler for automotive vehicles comprising a hollow inner length of tubing through which engine coolant may flow and an outer length of tubing sealed at its ends to the inner tubing and having an inner surface which cooperates with the outer surface of the inner length of tubing to define a generally annular flow passage for oil which may pass through inlet and outlet fittings at opposed ends of the cooler, the improvement wherein said inner length of tubing includes a helically convoluted outer surface and said outer length of tubing includes a plurality of generally axially extending flutes which engage said helically convoluted outer surface, the crests of said flutes being periodically transversely indented along the axial length thereof to a depth less than the depth of the flutes.
Claim 2
Dependent Claim
134 words
In a submerged oil cooler for automotive vehicles comprising a hollow inner length of tubing through which engine coolant may flow and an outer length of tubing sealed at its ends to the inner tubing and having an inner surface which cooperates with the outer surface of the inner length of tubing to define a generally annular flow passage for oil which may pass through inlet and outlet fittings at opposed ends of the cooler, the improvement wherein said inner length of tubing includes a helically convoluted outer surface and said outer length of tubing includes a plurality of generally axially extending flutes which engage said helically convoluted outer surface, the crests of said flutes being periodically transversely indented along the axial length thereof to a depth less than the depth of the flutes.
Claim 3
Dependent Claim
25 words
A submerged oil cooler in accordance with claim 1 wherein the inner length of tubing has helically convoluted, integral fins extending from its outer surface.
Claim 4
Dependent Claim
23 words
A submerged oil cooler in accordance with claim 1 wherein the inner length of tubing has helically convoluted corrugations on its outer surface.
Claim 5
Dependent Claim
27 words
A submerged oil cooler in accordance with claim 1 wherein said plurality of generally axially extending flutes are helically corrugated to form transverse indentations in said flutes.
Claim 6
Dependent Claim
22 words
A submerged oil cooler in accordance with claim 1 wherein said outer length of tubing contains between about 12 and 24 flutes.
Claim 7
Dependent Claim
62 words
A submerged oil cooler in accordance with claim 1 wherein said outer tubing has about 16 flutes which are about 0.070 in. deep, the crests of said flutes being indented about 0.036 in. deep at an axial pitch of about 0.2 in., and wherein said inner length of tubing includes about 26 integral, helically convoluted fins per inch on its outer surface.
Claim 8
Dependent Claim
30 words
A submerged oil cooler in accordance with claim 1 wherein said flutes have a depth of from about 0.040-0.100 inches and are indented to a depth of about 0.030-0.090 inches.
Claim 9
Dependent Claim
22 words
A submerged oil cooler in accordance with claim 7 wherein said indentations are axially spaced at a pitch of about 0.2-0.8 inches.
Claim 10
Dependent Claim
25 words
A submerged oil cooler in accordance with claim 8 wherein said inner length of tubing includes from about 11-26 integral fins per inch of length.
Claim 11
Dependent Claim
40 words
A submerged oil cooler in accordance with claim 8 wherein said inner length of tubing is generally smooth except for a helical corrugation in its wall having a depth of about 0.030-0.065 inches and a pitch of about 0.25-0.75 inches.
References Cited (Backward Citations)
FR640532A
Cited
US1689461A
Cited
GB615937A
Cited
US2752128A
Cited
US3384154A
Cited
US3235947A
Cited
US3177936A
Cited
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US3829285A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-01-25 | 1980-07-26 | 1981-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-01-25 | 1984-07-26 | 1985-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-01-25 | 1988-07-26 | 1989-01-25 | $7700.00 | Window Closed / Lapsed |