US4989568A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fuel injection system for outboard motors
Assignee: Yamaha Motor Co Ltd
•
Filing: 1987-07-22
•
Granted: 1991-02-05
•
Expires: 2007-07-22
Abstract
Abstract Several embodiments of fuel supply systems for outboard motors and particularly those embodying fuel injection systems and remotely positioned fuel tanks. In each embodiment, a device is incorporated in the power head of the outboard motor for maintaining a uniform pressure of fuel delivery to the fuel injection nozzles by recycling a portion of the fuel back into the fuel system and within the power head. In some embodiments, the fuel is recycled directly into the fuel line before the fuel pump. In others, the fuel is recycled to either a delivery tank or an accumulator chamber.
Inventors
- 👤 Masafumi Sougawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:53
CPC Classifications
F; F02; F02M; F02M69/00; F02M69/46; F02M69/462; F02D; F02D41/00; F02D41/30; F02D41/3082; F02M55/00; F02M69/465; F02B; F02B2275/00; F02B2275/14; F02B61/00; F02B61/04; F02B61/045; F02M55/007; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
136 words
An outboard motor fuel supply system, said outboard motor having a power head comprising an internal combustion engine and a surrounding protective cowling, a charge forming means for said internal combustion engine, propulsion means driven by said internal combustion engine from powering an associated watercraft through the water, a fuel tank for supplying fuel to said charge forming means, said fuel tank being positioned remotely from said power head and outside of said protective cowling, and conduit means for supply fuel from said fuel tank to said charge forming means, the improvement comprising pressure responsive valve means contained within said power head for regulating the pressure of fuel delivered from said fuel tank to said charge forming means including means for recycling excess fuel back to said conduit means and within said power head protective cowling.
Claim 2
Dependent Claim
136 words
An outboard motor fuel supply system, said outboard motor having a power head comprising an internal combustion engine and a surrounding protective cowling, a charge forming means for said internal combustion engine, propulsion means driven by said internal combustion engine from powering an associated watercraft through the water, a fuel tank for supplying fuel to said charge forming means, said fuel tank being positioned remotely from said power head and outside of said protective cowling, and conduit means for supply fuel from said fuel tank to said charge forming means, the improvement comprising pressure responsive valve means contained within said power head for regulating the pressure of fuel delivered from said fuel tank to said charge forming means including means for recycling excess fuel back to said conduit means and within said power head protective cowling.
Claim 3
Dependent Claim
20 words
A fuel supply system as set forth in claim 1 wherein the charge forming means comprises a fuel injection nozzle.
Claim 4
Dependent Claim
32 words
A fuel supply system as set forth in claim 1 wherein the conduit means includes a quick disconnect coupling between a flexible conduit extending from the fuel tank and the power head.
Claim 5
Dependent Claim
20 words
A fuel supply system as set forth in claim 3 wherein the charge forming means comprises a fuel injection nozzle.
Claim 6
Dependent Claim
42 words
A fuel supply system as set forth in claim 1 further including pressure pumping means for pumping fuel from the fuel tank to the charge forming means under pressure and the pressure regulating means is positioned upstream of the pressure pumping means.
Claim 7
Dependent Claim
22 words
A fuel supply system as set forth in claim 5 further including an auxiliary fuel delivery tank contained within the power head.
Claim 8
Dependent Claim
28 words
A fuel supply system as set forth in claim 6 further including float operated valve means for maintaining a uniform level of fuel within said fuel delivery tank.
Claim 9
Dependent Claim
32 words
A fuel supply system as set forth in claim 7 wherein the conduit means includes a quick disconnect coupling between a flexible conduit extending from the fuel tank and the power head.
Claim 10
Dependent Claim
20 words
A fuel supply system as set forth in claim 8 wherein the charge forming means comprises a fuel injection nozzle.
Claim 11
Dependent Claim
32 words
A fuel supply system as set forth in claim 5 wherein the conduit means includes a quick disconnect coupling between a flexible conduit extending from the fuel tank and the power head.
Claim 12
Dependent Claim
20 words
A fuel supply system as set forth in claim 10 wherein the charge forming means comprises a fuel injection nozzle.
Claim 13
Dependent Claim
39 words
A fuel supply system as set forth in claim 5 further including accumulator means disposed in the conduit means upstream of the pressure pumping means, the means for recycling excess fuel delivering the excess fuel to the accumulator means.
Claim 14
Dependent Claim
32 words
A fuel supply system as set forth in claim 12 wherein the conduit means includes a quick disconnect coupling between a flexible conduit extending from the fuel tank and the power head.
Claim 15
Dependent Claim
20 words
A fuel supply system as set forth in claim 13 wherein the charge forming means comprises a fuel injection nozzle.
Claim 16
Dependent Claim
19 words
A fuel supply system as set forth in claim 12 wherein the accumulator means comprises a closed volume chamber.
Claim 17
Dependent Claim
38 words
A fuel supply system as set forth in claim 12 wherein the accumulator means further includes a movable wall and a biasing means for urging the wall against the fuel to maintain a predetermined pressure in the fuel.
Claim 18
Dependent Claim
30 words
A fuel supply system as set forth in claim 5 wherein the pressure pumping means has an internal pressure regulator for returning excess fuel to the inlet to the pump.
Claim 19
Dependent Claim
32 words
A fuel supply system as set forth in claim 17 wherein the conduit means includes a quick disconnect coupling between a flexible conduit extending from the fuel tank and the power head.
Claim 20
Dependent Claim
21 words
A fuel supply system as set forth in claim 18 wherein the charge forming means comprises a fuel injection nozzle. d
References Cited (Backward Citations)
GB610248A
Cited
US2599699A
Cited
US2717584A
Cited
US4142497A
Cited
US4290394A
Cited
US4660516A
Cited
US4450820A
Cited
US4637355A
Cited
US4524744A
Cited
US4539965A
Cited
US4794889A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-04 | 1994-08-06 | 1995-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-04 | 1998-08-06 | 1999-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-04 | 2002-08-06 | 2003-02-05 | $7700.00 | Window Closed / Lapsed |