Patent US3979574A successfully refreshed from Google Patents.
US3979574A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tank type engine heater
Assignee: Martinrea Kitchener Frame Ltd
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Filing: 1975-03-31
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Granted: 1976-09-07
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Expires: 1995-03-31
Abstract
Abstract An electric tank heater for heating the engine coolant system of an automotive vehicle comprises a tubular tank shell having an open end in which is secured an annulus having a U-shaped wall. The outer leg of the annulus is circumferentially secured and sealed the shell. The inner leg extends inwardly through the end of the shell and is spaced from the inner surface thereof. A removable closure plug member from which an electric immersion heating element depends for projection into the shell is inserted into the annulus and seals against the inner leg thereof with an O-ring seal. The closure plug member is retained in place by a yoke engaging the edge of inner leg.
Inventors
- 👤 Richard Haig John Rynard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 03:22
CPC Classifications
F; F02; F02N; F02N19/00; F02N19/02; F02N19/04; F02N19/10; H; H05; H05B; H05B3/00; H05B3/02; H05B3/06
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
141 words
In a tank heater comprising a shell having liquid inlet and outlet conduits and having an opening therein adapted to be closed by a closure means including a closure member, said closure member having an electric immersion heating element dependent therefrom to project into said shell, said closure member comprising a plug having an annular wall portion, an O ring sealing member girdling said annular wall portion, and means to retain said closure member in its closed position, the improvement wherein said closure means includes an annulus having a U-shaped wall, the outer leg thereof being circumferentially connected in sealed relation to said opening, the inner leg thereof extending inwardly of said opening and being spaced from the inner surface of said shell, said O ring sealing member engaging said inner leg when said closure member is inserted into said annulus.
Claim 2
Dependent Claim
141 words
In a tank heater comprising a shell having liquid inlet and outlet conduits and having an opening therein adapted to be closed by a closure means including a closure member, said closure member having an electric immersion heating element dependent therefrom to project into said shell, said closure member comprising a plug having an annular wall portion, an O ring sealing member girdling said annular wall portion, and means to retain said closure member in its closed position, the improvement wherein said closure means includes an annulus having a U-shaped wall, the outer leg thereof being circumferentially connected in sealed relation to said opening, the inner leg thereof extending inwardly of said opening and being spaced from the inner surface of said shell, said O ring sealing member engaging said inner leg when said closure member is inserted into said annulus.
Claim 3
Dependent Claim
24 words
A tank heater as defined in claim 1, wherein said shell comprises a tube and wherein said opening comprises one end of said tube.
Claim 4
Dependent Claim
18 words
A tank heater as defined in claim 2 wherein said annulus is formed separately from said tube wall.
Claim 5
Dependent Claim
28 words
A tank heater as defined in claim 3 wherein said retaining means includes a yoke engaging shoulders formed by the edge of the inner leg of said annulus.
References Cited (Backward Citations)
US1875306A
Cited
US2367197A
Cited
US2408403A
Cited
US2400838A
Cited
FR1059165A
Cited
GB760990A
Cited
US3209123A
Cited
GB1088250A
Cited
US3646314A
Cited
US3766356A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-07 | 1980-03-08 | 1980-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-07 | 1984-03-08 | 1984-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-07 | 1988-03-08 | 1988-09-07 | $7700.00 | Window Closed / Lapsed |