US4402297A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intake system of engines
Assignee: Yamaha Motor Co Ltd
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Filing: 1981-06-25
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Granted: 1983-09-06
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Expires: 2001-06-25
Abstract
Abstract An induction system for an internal combustion engine embodying a plenum chamber that communicates with the intake system between the carburetor and the engine chamber so as to promote continuous flow even at low speeds to improve low speed charging efficiency. A fuel return conduit separately communicates the plenum chamber with the intake passage for returning condensed fuel in a relatively continuous fashion to the intake passage so as to avoid mixture strength variations.
Inventors
- 👤 Motoaki Hyodo
- 👤 Soichi Anma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:57
CPC Classifications
F; F02; F02B; F02B27/00; F02B27/003; F02B61/00; F02B61/02; F02M; F02M33/00; F02M33/02; F02M33/04; F02B75/00; F02B75/02; F02B2075/022; F02B2075/025; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
157 words
An induction system for an internal combustion engine having a chamber that cyclically varies in volume, an intake passage communicating with said chamber, a charge forming device for delivering a charge to said intake passage, a throttle valve in said intake passage for controlling the flow therethrough, a plenum chamber, and conduit means communicating said plenum chamber with a portion of said intake passage upstream of said variable volume chamber and downstream of said charge forming device and said throttle valve, the improvement comprising said plenum chamber having a lower wall with a fuel return opening formed therein at a point vertically above said intake passage portion, said fuel return opening being spaced from the opening of said conduit means into said plenum chamber, and a fuel return conduit extending generally vertically and communicating said fuel return opening with said intake passage for returning condensed fuel from said plenum chamber to said intake passage by gravity flow.
Claim 2
Dependent Claim
157 words
An induction system for an internal combustion engine having a chamber that cyclically varies in volume, an intake passage communicating with said chamber, a charge forming device for delivering a charge to said intake passage, a throttle valve in said intake passage for controlling the flow therethrough, a plenum chamber, and conduit means communicating said plenum chamber with a portion of said intake passage upstream of said variable volume chamber and downstream of said charge forming device and said throttle valve, the improvement comprising said plenum chamber having a lower wall with a fuel return opening formed therein at a point vertically above said intake passage portion, said fuel return opening being spaced from the opening of said conduit means into said plenum chamber, and a fuel return conduit extending generally vertically and communicating said fuel return opening with said intake passage for returning condensed fuel from said plenum chamber to said intake passage by gravity flow.
Claim 3
Dependent Claim
38 words
In an induction system as set forth in claim 1 wherein the fuel return conduit is sized so as to preclude any substantial air flow between the plenum chamber and the intake passage through said fuel return conduit.
Claim 4
Dependent Claim
39 words
In an induction system as set forth in claim 1 wherein the fuel return conduit communicates with the intake passage upstream of the variable volume chamber and downstream of both of the charge forming device and the throttle valve.
Claim 5
Dependent Claim
38 words
In an induction system as set forth in claim 3 wherein the fuel return conduit is sized so as to preclude any substantial air flow between the plenum chamber and the intake passage through said fuel return conduit.
Claim 6
Dependent Claim
34 words
In an induction system as set forth in claims 1, 2, 3 or 4 wherein the throttle valve is a part of the charge forming device and the charge forming device comprises a carburetor.
Claim 7
Dependent Claim
52 words
An induction system as set forth in claim 5 further including check valve means interposed between the intake passage and the chamber and downstream of the portion of the intake passage for permitting flow from the intake passage into the chamber and precluding flow from the chamber back into the intake passage.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-05 | 1987-03-07 | 1987-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-05 | 1991-03-07 | 1991-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-05 | 1995-03-07 | 1995-09-06 | $7700.00 | Window Closed / Lapsed |