US4993375A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Engine cylinder head cover
Assignee: Nissan Motor Co Ltd
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Filing: 1990-05-11
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Granted: 1991-02-19
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Expires: 2010-05-11
Abstract
Abstract To scavenge blow-by gas blown into a crank case with newly introduced external air at high replacement efficiency and further to provide oil separating baffle plates at both the main oil-separation passage and the subsidiary oil separation passage (used when blow-by gas follows in the reverse direction from the external air outlet to the external air inlet), the external air outlet and the blow-by gas inlet are located in diagonally furthest positional relationship with respect to each other within the cylinder head cover; and further a U-shaped blow-by gas passage including the main oil-separation passage is arranged on one longitudinal space of the head cover and another U-shaped external air passage including the subsidiary oil-separation passage is also arranged on the other longitudinal space of the head cover.
Inventors
- 👤 Sobue Akihiko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 19:10
CPC Classifications
F; F01; F01M; F01M13/00; F01M13/04; F01M13/0416; F02; F02F; F02F7/00; F02F7/006; F02B; F02B2275/00; F02B2275/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
249 words
An engine cylinder head cover formed with a chain casing and a middle longitudinal recessed portion extending along a cylinder arrangement direction, comprising: (a) an external air inlet; (b) an external air outlet formed near and on the same head cover end side as said external air inlet so as to communicate with an engine crank case; (c) an external air passage formed along one side surface of the middle longitudinal recessed portion and having a first end connected to said external air inlet; (d) a subsidiary oil-separation passage formed in parallel with and outside said external air passage and having a first end connected to said external air outlet, a second end of said external air passage being connected to a second end of said subsidiary oil-separation passage in U-shaped fashion; (e) a blow-by gas inlet formed diagonally remote from said external air outlet so as to communicate with the engine crank case; (f) a blow-by gas outlet formed on the same head cover end side as said blow-by gas inlet; (g) a blow-by gas passage formed along the other side surface of the middle longitudinal recessed portion and having a first end connected to said blow-by gas outlet; and (h) a main oil-separation passage formed in parallel with and outside said blow-by gas passage and having a first end connected to said blow-by gas inlet, a second end of said blow-by gas passage being connected to a second end of said main oil-separation passage in U-shaped fashion.
Claim 2
Dependent Claim
249 words
An engine cylinder head cover formed with a chain casing and a middle longitudinal recessed portion extending along a cylinder arrangement direction, comprising: (a) an external air inlet; (b) an external air outlet formed near and on the same head cover end side as said external air inlet so as to communicate with an engine crank case; (c) an external air passage formed along one side surface of the middle longitudinal recessed portion and having a first end connected to said external air inlet; (d) a subsidiary oil-separation passage formed in parallel with and outside said external air passage and having a first end connected to said external air outlet, a second end of said external air passage being connected to a second end of said subsidiary oil-separation passage in U-shaped fashion; (e) a blow-by gas inlet formed diagonally remote from said external air outlet so as to communicate with the engine crank case; (f) a blow-by gas outlet formed on the same head cover end side as said blow-by gas inlet; (g) a blow-by gas passage formed along the other side surface of the middle longitudinal recessed portion and having a first end connected to said blow-by gas outlet; and (h) a main oil-separation passage formed in parallel with and outside said blow-by gas passage and having a first end connected to said blow-by gas inlet, a second end of said blow-by gas passage being connected to a second end of said main oil-separation passage in U-shaped fashion.
Claim 3
Dependent Claim
75 words
The engine cylinder head cover of claim 1, which further comprises: a plurality of blow-by gas passage baffle plates alternately arranged in said main oil-separation passage so as to extend from above and below in such a way that blow-by gas flows therethrough being moved up and down along said baffle plates to separate oil included in blow-by gas flowing from said blow-by gas inlet to said blow-by gas outlet under normal engine operating conditions.
Claim 4
Dependent Claim
82 words
The engine cylinder head cover of claim 1, which further comprises: a plurality of air passage baffle plates alternately arranged in said subsidiary oil-separation passage so as to extend from above and below in such a way that external air flows therethrough being moved up and down along said baffle plates to separate oil included in blow-by gas reversely flowing from said external air outlet to said external air inlet when an engine is running at high speed and under heavy load.
Claim 5
Dependent Claim
36 words
The engine cylinder head cover of claim 1, wherein said subsidiary oil-separation passage is sloped down from a U-shaped connection end between said external air passage and said subsidiary oil-separation passage to said external air outlet.
Claim 6
Dependent Claim
35 words
The engine cylinder head cover of claim 1, wherein said main oil-separation passage is sloped up from said blow-by gas inlet to a U-shaped connection end between said main oil-separation passage and said gas passage.
Claim 7
Dependent Claim
21 words
The engine cylinder head cover of claim 1, which further comprises an oil discharge part formed in said main oil-separation passage.
Claim 8
Dependent Claim
28 words
The engine cylinder head cover of claim 1, which further comprises a transversal blow-by gas passage (29) connected between said blow-by gas passage and said blow-by gas outlet.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-18 | 1994-08-20 | 1995-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-18 | 1998-08-20 | 1999-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-18 | 2002-08-20 | 2003-02-19 | $7700.00 | Window Closed / Lapsed |