Patent US4727833A successfully refreshed from Google Patents.
US4727833A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sealing structure of cylinder head cover
Assignee: Toyota Motor Corp
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Filing: 1986-11-12
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Granted: 1988-03-01
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Expires: 2006-11-12
Abstract
Abstract A structure for mounting a cylinder head cover on an engine cylinder head, having plug holes for mounting ignition plugs. A plug tube is fixedly inserted into each plug hole and the cylinder head cover is mounted on the cylinder head via a sealing gasket. The cylinder head cover has mount holes, each of which is formed in a reverse-conical surface. A grommet having an annular sealing lip is fitted to the upper end of the plug tube and a fastening nut is engaged with a male thread portion of the plug tube to urge the grommet downward so that the sealing lip is sealingly engaged with the reverse-conical face of the cylinder head cover and an outer peripheral surface of the plug tube, so as to tightly seal away oil contained in the cylinder head cover.
Inventors
- 👤 Mikio Nakashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:23
CPC Classifications
F; F02; F02F; F02F1/00; F02F1/24; F02F1/242; F02F7/00; F02F7/006; F02B; F02B1/00; F02B1/02; F02B1/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
204 words
A structure for mounting a cylinder head cover on a cylinder head of an internal combustion engine, the cylinder head having plug holes for mounting ignition plugs therethrough, a plug tube fixedly inserted into each of the plug holes and protruding upward from the cylinder head, the cylinder head cover being mounted on the cylinder head via a sealing gasket arranged therealong, wherein said mounting structure comprises: the cylinder head cover having plug mounting holes, each of which is formed in substantially reversed-conical surface having a diameter that becomes gradually smaller toward the lower portion thereof, the plug tube having a male thread portion at an upper end thereof protruding upward from the cylinder head cover through the plug mounting hole, a grommet having an annular sealing lip fitted to the upper end of the plug tube, and a fastening nut engaged with and fastened to a male thread portion of the plug tube to urge the grommet downward so that said sealing lip of the grommet is sealingly pressed into a gap between the reverse-conical surface of the cylinder head cover and an outer peripheral surface of the plug tube, so as to tightly seal away oil contained in the cylinder head cover.
Claim 2
Dependent Claim
204 words
A structure for mounting a cylinder head cover on a cylinder head of an internal combustion engine, the cylinder head having plug holes for mounting ignition plugs therethrough, a plug tube fixedly inserted into each of the plug holes and protruding upward from the cylinder head, the cylinder head cover being mounted on the cylinder head via a sealing gasket arranged therealong, wherein said mounting structure comprises: the cylinder head cover having plug mounting holes, each of which is formed in substantially reversed-conical surface having a diameter that becomes gradually smaller toward the lower portion thereof, the plug tube having a male thread portion at an upper end thereof protruding upward from the cylinder head cover through the plug mounting hole, a grommet having an annular sealing lip fitted to the upper end of the plug tube, and a fastening nut engaged with and fastened to a male thread portion of the plug tube to urge the grommet downward so that said sealing lip of the grommet is sealingly pressed into a gap between the reverse-conical surface of the cylinder head cover and an outer peripheral surface of the plug tube, so as to tightly seal away oil contained in the cylinder head cover.
Claim 3
Dependent Claim
38 words
A structure as set forth in claim 1, wherein the reverse-conical surface of the plug mounting hole of the cylinder head cover has an angle of 10° to 30° in axial cross-section with respect to an axial direction.
Claim 4
Dependent Claim
27 words
A structure as set forth in claim 1, wherein the grommet comprises a metal ring to which the annular sealing lip made of rubber is vulcanizingly adhered.
Claim 5
Dependent Claim
60 words
A structure as set forth in claim 3, wherein the annular rubber sealing lip is formed substantially in an L-shape in the axial cross-section thereof such that a lower portion thereof opposite to the metal ring is elongated downward to sealingly engage with the reverse-conical surface of the cylinder head cover and the outer peripheral surface of the plug tube.
References Cited (Backward Citations)
US3144013A
Cited
US3521726A
Cited
JPS5431716A
Cited
US4338889A
Cited
US4495903A
Cited
JPS60167144A
Cited
JPS6123595A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-03-01 | 1991-08-31 | 1992-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-01 | 1995-08-31 | 1996-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-01 | 1999-08-31 | 2000-03-01 | $7700.00 | Window Closed / Lapsed |