Patent US4421087A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4421087A Expired / Lapsed US ⏱️ 0.0 years remaining

Alternative liquid fuel injection system and method

Assignee: Individual
•
Filing: 1982-02-05
•
Granted: 1983-12-20
•
Expires: 2002-02-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A liquid fuel injection system for an internal combustion engine in which the fuel, gaseous under ambient conditions, is injected in liquid form under compression into the intake manifold of the engine. Fuel is controlled largely by intake manifold pressure together with the RPM of the engine. Some fuel bypasses the injector, is vaporized and fed into the intake manifold through a sleeve in sufficient amounts to maintain the engine at idle and low load conditions and prevent the injector from freezing.

Inventors

  • 👤 Eiko A. Schuurman

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 20:46
CPC Classifications
F; F02; F02M; F02M21/00; F02M21/02; F02M21/0203; F02M21/0209; F02M21/0212; F02D; F02D19/00; F02D19/02; F02D19/021; F02D19/022; F02M21/0218; F02M21/0248; F02M21/0278; F02M21/0287; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/30

Claims Analysis

Total Claims: 22
Claim 1
Independent Claim 109 words
A fuel injection system for an internal combustion engine having an intake manifold comprising: (a) means for supplying a gaseous fuel in a liquid state; (b) means for receiving said fuel and injecting same in a liquid state directly into said intake manifold; (c) means responsive to predetermined engine conditions for controlling the rate at which fuel is supplied to said manifold by said injecting means; and (d) means for providing vaporized fuel for starting and idling conditions comprising bypass means for withdrawing up to 10% by volume of said fuel prior to injection, vaporizing the bypassed fuel and delivering same to said intake manifold, bypassing said injecting means.
Claim 2
Dependent Claim 109 words
A fuel injection system for an internal combustion engine having an intake manifold comprising: (a) means for supplying a gaseous fuel in a liquid state; (b) means for receiving said fuel and injecting same in a liquid state directly into said intake manifold; (c) means responsive to predetermined engine conditions for controlling the rate at which fuel is supplied to said manifold by said injecting means; and (d) means for providing vaporized fuel for starting and idling conditions comprising bypass means for withdrawing up to 10% by volume of said fuel prior to injection, vaporizing the bypassed fuel and delivering same to said intake manifold, bypassing said injecting means.
Claim 3
Dependent Claim 21 words
The system of claim 1 in which the amount of fuel being bypassed is sufficient to maintain said engine at idle.
Claim 4
Dependent Claim 17 words
The system of claim 2 in which said injecting means is inoperative when said engine is idling.
Claim 5
Dependent Claim 18 words
The system of claim 3 in which said injecting means becomes operative at some predetermined engine load condition.
Claim 6
Dependent Claim 22 words
The system of claim 4 in which said controlling means includes regulator means responsive to changes in intake manifold and fuel pressures.
Claim 7
Dependent Claim 31 words
The system of claim 5 in which said controlling means also includes electrical computer means responsive to said regulator means for controlling the rate of fuel delivered by said injecting means.
Claim 8
Dependent Claim 35 words
The system of claim 6 in which said computer means is also responsive to the RPM of said engine and said computer means is programmed to supply fuel in predetermined amounts under any load condition.
Claim 9
Dependent Claim 23 words
The system of claim 7 in which said computer means is programmed to provide fuel injection during cold start conditions of said engine.
Claim 10
Dependent Claim 24 words
The system of claim 7 in which the load on said engine is determined by inlet manifold vacuum and the RPM of said engine.
Claim 11
Dependent Claim 33 words
The system of claim 9 in which said computer means is also responsive to other engine conditions including emissions and engine temperature, and also affects the control of ignition timing of said engine.
Claim 12
Dependent Claim 40 words
The system of claim 4 in which said injecting means is provided with sleeve means for feeding the bypassed, vaporized fuel into said intake manifold, the heat contained within the vaporized fuel simultaneously preventing freezing conditions in said injecting means.
Claim 13
Dependent Claim 23 words
The system of claim 5 in which said bypass means includes means for controlling the flow of vaporized fuel into said intake manifold.
Claim 14
Dependent Claim 19 words
The system of claim 12 in which said flow controlling means is responsive to changes in intake manifold pressure.
Claim 15
Dependent Claim 26 words
The system of claim 13 in which loss of vacuum in said intake manifold causes said flow controlling means to block all flow of vaporized fuel.
Claim 16
Dependent Claim 29 words
The system of claim 13 having means responsive to blockage of all flow by said flow controlling means to cause blockage of flow of liquid to said injecting means.
Claim 17
Independent Claim 104 words
The method of controlling delivery of liquefied gaseous fuel to an internal combustion engine, said engine having an intake manifold and means for injecting said liquid fuel into said intake manifold, comprising the steps of: (a) regulating flow of fuel in liquid form to said injecting means in accordance with inlet manifold and liquid fuel pressures; (b) bypassing said injecting means with up to 10% by volume of said liquid fuel; (c) vaporizing the bypassed fuel; (d) delivering the vaporized bypassed fuel directly into said intake manifold, the amount of fuel bypassed and vaporized being used to start and maintain said engine at idle.
Claim 18
Independent Claim 104 words
The method of controlling delivery of liquefied gaseous fuel to an internal combustion engine, said engine having an intake manifold and means for injecting said liquid fuel into said intake manifold, comprising the steps of: (a) regulating flow of fuel in liquid form to said injecting means in accordance with inlet manifold and liquid fuel pressures; (b) bypassing said injecting means with up to 10% by volume of said liquid fuel; (c) vaporizing the bypassed fuel; (d) delivering the vaporized bypassed fuel directly into said intake manifold, the amount of fuel bypassed and vaporized being used to start and maintain said engine at idle.
Claim 19
Dependent Claim 27 words
The method of claim 16 in which said injecting means is rendered inoperative during engine idle and rendered operative above some predetermined load condition of said engine.
Claim 20
Dependent Claim 28 words
The method of claim 17 in which the amount of vaporized fuel being fed into said intake manifold is adjusted in accordance with changes in intake manifold pressure.
Claim 21
Dependent Claim 23 words
The method of claim 18 in which the flow of vaporized fuel is blocked when no vacuum is present in said intake manifold.
Claim 22
Dependent Claim 18 words
The method of claim 19 in which liquid fuel flow is blocked when vaporized fuel flow is blocked.

References Cited (Backward Citations)

US2376479A Cited
US2767691A Cited
US3565201A Cited
US3978823A Cited
US4015569A Cited
US4296722A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-12-19 1987-06-20 1987-12-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-12-19 1991-06-20 1991-12-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-12-19 1995-06-20 1995-12-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag