US4349003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust gas recirculation control valve
Assignee: Toyota Motor Corp
•
Filing: 1980-06-17
•
Granted: 1982-09-14
•
Expires: 2000-06-17
Abstract
Abstract An exhaust gas recirculation control valve for preventing carbon and the like contained in the exhaust gas from attaching to the inner wall surface of exhaust gas paths, through which the exhaust gas from an engine of a motor car passes, thus decreasing the diameters of the paths with time. This exhaust gas recirculation control valve is provided in a passageway, through which the exhaust gas from the engine is recirculated into an intake air-fuel mixture, a path being of a frusto-conical shape in cross-section and having a progressively larger diameter toward an exhaust gas inlet is formed upstream of the minimum diameter portion, and the inner diameter of the smallest diameter end of said path being of the frusto-conical shape in cross-section in the vicinity of said minimum diameter portion is larger than the inner diameter of said minimum diameter portion. The path being of the frusto-conical shape in cross-section may be formed of a valve housing separately manufactured of a valve seat.
Inventors
- 👤 Yoshihiko Masuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 09:01
CPC Classifications
F; F02; F02M; F02M26/00; F02M26/52; F02M26/55; F02M26/50; F02M26/65; F02M26/66; F02M26/68
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
212 words
An exhaust gas recirculation control valve provided in a passageway through which an exhaust gas of an engine is recirculated into an intake air-fuel mixture, said exhaust gas recirculation control valve comprising: a valve orifice member with a through hole defining a pass; and a valve body to open or close said pass; said pass comprising in the following order from downstream to upstream: a tapered seat tapering toward upstream for receiving said valve body to contact sealingly with said valve body; a cylindrical minimum diameter portion with a same diameter of an upstream end of said tapered seat; a stepped portion perpendicular to the minimum diameter portion facing upstream for collecting deposits; a cylindrical pass with a diameter greater than the diameter of said cylindrical minimum diameter portion; and a frusto-conical pass tapering toward downstream, the downstream end of said frusto-conical pass having a same diameter as said cylindrical pass, whereby deposits from said exhaust gas are concentratingly attached to the stepped portion so that the deposits on the inner surface of said cylindrical minimum diameter portion, on said stepped portion, on the inner surface of said cylindrical pass and on the inner surface of the frusto-conical pass define a pass with a gradually increasing inner diameter in an upstream direction.
Claim 2
Dependent Claim
212 words
An exhaust gas recirculation control valve provided in a passageway through which an exhaust gas of an engine is recirculated into an intake air-fuel mixture, said exhaust gas recirculation control valve comprising: a valve orifice member with a through hole defining a pass; and a valve body to open or close said pass; said pass comprising in the following order from downstream to upstream: a tapered seat tapering toward upstream for receiving said valve body to contact sealingly with said valve body; a cylindrical minimum diameter portion with a same diameter of an upstream end of said tapered seat; a stepped portion perpendicular to the minimum diameter portion facing upstream for collecting deposits; a cylindrical pass with a diameter greater than the diameter of said cylindrical minimum diameter portion; and a frusto-conical pass tapering toward downstream, the downstream end of said frusto-conical pass having a same diameter as said cylindrical pass, whereby deposits from said exhaust gas are concentratingly attached to the stepped portion so that the deposits on the inner surface of said cylindrical minimum diameter portion, on said stepped portion, on the inner surface of said cylindrical pass and on the inner surface of the frusto-conical pass define a pass with a gradually increasing inner diameter in an upstream direction.
Claim 3
Dependent Claim
45 words
An exhaust gas recirculation control valve as set forth in claim 1, characterized in that an annular ridge projecting toward an exhaust gas inlet or the center of the valve is provided at a connecting portion between said frusto-conical pass and said minimum diameter portion.
Claim 4
Dependent Claim
28 words
An exhaust gas recirculation control valve as set forth in claim 1, wherein said frusto-conical pass is formed of a valve housing separately manufactured of the valve orifice.
References Cited (Backward Citations)
US3989018A
Cited
US4106449A
Cited
JPS5397219A
Cited
JPS54105621A
Cited
JPS54153922A
Cited
JPS5523381A
Cited
US4266524A
Cited
JPS5584847A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-09-13 | 1986-03-15 | 1986-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-09-13 | 1990-03-15 | 1990-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-09-13 | 1994-03-15 | 1994-09-14 | $7700.00 | Window Closed / Lapsed |