WO1998021463A1 - Commande d'alimentation en carburant gazeux et vaporisateur de carburant - Google Patents

Commande d'alimentation en carburant gazeux et vaporisateur de carburant Download PDF

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Publication number
WO1998021463A1
WO1998021463A1 PCT/AU1997/000776 AU9700776W WO9821463A1 WO 1998021463 A1 WO1998021463 A1 WO 1998021463A1 AU 9700776 W AU9700776 W AU 9700776W WO 9821463 A1 WO9821463 A1 WO 9821463A1
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WO
WIPO (PCT)
Prior art keywords
engine
fuel system
fuel
valve
piston
Prior art date
Application number
PCT/AU1997/000776
Other languages
English (en)
Other versions
WO1998021463A9 (fr
Inventor
Paul Turner
Original Assignee
Smartgas Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Smartgas Limited filed Critical Smartgas Limited
Priority to AU49348/97A priority Critical patent/AU4934897A/en
Publication of WO1998021463A1 publication Critical patent/WO1998021463A1/fr
Publication of WO1998021463A9 publication Critical patent/WO1998021463A9/fr

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
    • F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
    • F02M21/0218—Details on the gaseous fuel supply system, e.g. tanks, valves, pipes, pumps, rails, injectors or mixers
    • F02M21/023—Valves; Pressure or flow regulators in the fuel supply or return system
    • F02M21/0239—Pressure or flow regulators therefor
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D19/00—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures
    • F02D19/02—Controlling engines characterised by their use of non-liquid fuels, pluralities of fuels, or non-fuel substances added to the combustible mixtures peculiar to engines working with gaseous fuels
    • F02D19/021—Control of components of the fuel supply system
    • F02D19/022—Control of components of the fuel supply system to adjust the fuel pressure, temperature or composition
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
    • F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
    • F02M21/06—Apparatus for de-liquefying, e.g. by heating
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
    • F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
    • F02M21/0203—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels characterised by the type of gaseous fuel
    • F02M21/0209—Hydrocarbon fuels, e.g. methane or acetylene
    • F02M21/0212—Hydrocarbon fuels, e.g. methane or acetylene comprising at least 3 C-Atoms, e.g. liquefied petroleum gas [LPG], propane or butane
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
    • F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
    • F02M21/0203—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels characterised by the type of gaseous fuel
    • F02M21/0215—Mixtures of gaseous fuels; Natural gas; Biogas; Mine gas; Landfill gas
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
    • F02M21/00—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form
    • F02M21/02—Apparatus for supplying engines with non-liquid fuels, e.g. gaseous fuels stored in liquid form for gaseous fuels
    • F02M21/04—Gas-air mixing apparatus
    • F02M21/047—Venturi mixer
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/30—Use of alternative fuels, e.g. biofuels

Definitions

  • This invention relates to a fuel system.
  • This invention has particular but not exclusive application to a vehicle fuel system utilizing LPG or CNG, and for illustrative purposes reference will be made to such application.
  • this invention could be used in other applications, such as fuel systems for apparatus other than vehicles using gaseous or vaporizable fuels.
  • LPG Liquefied Petroleum Gas
  • CNG Compressed Natural Gas
  • a demand regulated vaporizer is adapted to receive LPG from a storage tank, the vaporizer being used to feed a demand air/fuel mixer and thence the engine.
  • a multistage fuel heater/pressure reduction apparatus similarly feeds an air/fuel mixer.
  • the rules for LPG and CNG vehicles specify that where a vehicle has an engine management system installed from the factory (OEM) the gas system shall also have an engine management system that gives gas emissions not inferior to the original system.
  • OEM factory
  • a problem with connection to the original petrol system is that this petrol system is trying to Control the engine emissions from the oxygen sensor to a preset stoichiometric air/fuel ratio (AFR) of approximately 14.5:1.
  • AFR air/fuel ratio
  • the LPG system needs to run the engine at an induced charge ratio of approximately 15.5:1. This causes the engine management system to run lean on emissions.
  • the main thrust of development has been to control the feedback by installing stepper motors operating a taper or shaped pistons to control the gas.
  • the systems proposed to date have high end cost, lack reliability, and do not control as well as the original powervalve, whilst meeting the technical requirement of the standards.
  • the present invention aims to substantially alleviate at least one of the above disadvantages and to provide a fuel system which will be reliable and efficient in use.
  • this invention in one aspect resides broadly in a fuel system including a fuel supply adapted to deliver gaseous fuel to an internal combustion engine and delivery regulating means comprising a valve operable according to engine demand and a trim valve responsive to engine emission status.
  • the fuel supply may take any suitable form in general determined by the selection of fuel or fuels to be utilized.
  • the fuel supply may comprise vaporizer apparatus adapted to utilize waste heat from the engine cooling system or exhaust gases to vaporize the fuel.
  • the gas may be warmed by similar means adapted for this fuel tanked in the gaseous phase.
  • the valve operable according to engine demand may comprise any suitable valve disposed in the gas flow such as a butterfly valve, gate valve, or the like disposed in a delivery line.
  • the means for operating the valve in response to engine demand may utilize such arbitrary measure of demand as throttle position. However, it is preferred that the valve be operated by means responsive to engine manifold depression or vacuum, and functioning as a "power valve" in the language of the art.
  • the power valve may comprise an operating diaphragm which reacts to engine vacuum and either adds or removes cross sectional area to a region of the gas line supplying fuel to the engine.
  • the power valve may comprise an assembly of a load block having a flow passage therethrough which is selectively occludable by a piston mounted in a main body in the load block and operable by the diaphragm. As engine vacuum is directly proportional to engine demand this valve assembly may be made adjustable by screwing the main body directly into the load- block to a preset distance as required by the type of engine being fitted.
  • the piston may be mounted in a bore in the main body which is substantially transverse to the direction of gas flow through the load block.
  • the piston in occluding the gas supply line blocking the path of gas, blocks the vacuum signal from the engine venturi thus creating less demand on the vaporizer.
  • this piston is spring biased to a normally-retracted position and can extend fully into the gas supply line at high Hg and retract into housing body proportional to the lower Hg.
  • the maximum travel of this piston is preferably controllable so that the maximum demand of the engine can be catered for.
  • the trim valve responsive to engine emission status may be responsive to any selected measurable emission characteristic.
  • the trim valve may be responsive to carbon monoxide or nitrogen oxides content of a selected part of the exhaust gas flow.
  • conventional emission control apparatus for use in conjunction with the original petrol fuel system of most vehicles includes a residual oxygen sensor, this may be utilized to provide the primary input of emission status of the exhaust gas flow.
  • the powervalve piston is, in essence, the coarse control mechanism by which the vehicle may be set up to operate over substantially the full range of demand.
  • the trim valve preferably provides fine control of the gas flow to a precision, based on exhaust emissions, not achievable with the powervalve.
  • the trim valve is formed as an assembly with the power valve.
  • the trim valve may include a further piston installed in the preferred load body and opposing the travel of the power valve piston.
  • This second piston may be controlled by any suitable means responsive to the exhaust emissions monitored.
  • the piston may be controlled by a stepper motor, solenoid or the like under the control of microprocessor means or an output of engine management means.
  • the trim piston is electronically controlled by a solenoid under the operational control of a programmable controller unit which has pre-sets for the emission "window" to be achieved.
  • the electronic controller program may view the output received from the oxygen sensor and may react according to the pre-set programme to "pulse" the solenoid, moving the trim valve piston and thus trim the effective power valve actuation to the required emissions.
  • the maximum travel of the solenoid shuttle is preferably limited by design to trim and control during the cruise mode where the solenoid shuttle will be pulsing in and out and have the maximum influence. In an idle situation where the two pistons will be closed face to face, a designed amount of leakage past the piston diameters may allow idle fuel as metered by the adjustable idle screw on the vaporizer to maintain idle, although it is envisaged that a separate idle system may be provided.
  • the solenoid shuttle will have no influence and will remain at full extension waiting to trim the mixture when required.
  • the combination vacuum powervalve/electronic trim solenoid control for cruise mode may incorporate in its control .means a mode for idle control in the idle range.
  • the idle circuit includes an on/off solenoid with electronic control from the controller which measures the oxygen sensor output and converts to a pre-controlled program within the controller to give an emission window within the set range. In idle mode this may be achieved by pulsing the idle solenoid as required to give a LP gas flow suitable for the engine conditions being monitored.
  • the idle solenoid preferably receives a signal from the throttle position switch that the cruise control situation is being entered and the electronic solenoid in the gas supply line trims the vacuum signal powervalve to the pre-set conditions.
  • the present system uses a vacuum/electronic trim solenoid control in the cruise mode but also incorporates a pulse idle valve for idle control in the idle range.
  • the design of the vaporizer idle circuit is an on/off solenoid with electronic control from the controller which measures the oxygen sensor output and converts to a pre-controlled programme within the controller unit to give an emission window within the set range. In idle mode this is accomplished by pulsing the idle solenoid as required to give a LP gas flow suitable for the engine conditions being monitored. In transition to the idle ⁇ cruise mode the idle solenoid receives a signal from the throttle position switch that the cruise control situation is being entered and the electronic solenoid in the gas supply line trims the vacuum signal powervalve to the pre-set conditions.
  • the present applicant has developed a system that uses the original powervalve concept in conjunction with an electronic trim control which has all the benefits of the original system, speed of operation, instant response, low initial cost and "fail to safe" in case of failure in the feedback system.
  • An advantage of the above described apparatus is that in the event of solenoid or electronic failure, the limited travel of the shuttle will not effect a total shut down condition.
  • the preferred powervalve being vacuum operated, has a very high reliability rate.
  • the vehicle could still be driven to a place of repair.
  • Other types of controllers on the market either fail in the position they were last in or fail fully shut or fully open. In these circumstances, a vehicle could not be controllable and would have to be transported.
  • the vacuum powervalve By keeping the vacuum powervalve as the coarse control and relying on the solenoid valve to trim the resulting emissions it is a smoother and much faster reacting system than electronic designs that have stepper motors or vane valves. In the event of engine demand to full power requirements, the vacuum powervalve responds to engine demand and moves instantly (faster than a stepper motor) to full open position as set by the adjustable full power pre-set.
  • the idle system of the apparatus as described may comprise allowing gas bypass of the powervalve piston and the solenoid trim shuttle.
  • This bypass "leak” is usually controlled by an idle screw in the solenoid and is set to the engine's requirements. It has been determined that the same principal of operation for trimming cruise emissions can be applied to idle control.
  • An idle control solenoid on the vaporizer may be pulsed in response to the controllers demands and in such fashion control the idle gas requirements to a much finer degree than a fixed aperture and adjustable screw can accomplish.
  • the input signal from the throttle position switch may be used to signal the controller that the engine throttle is in the closed position and sets the idle solenoid on the vaporizer to cycle in response to the pre-set program in the controller. In this situation it is possible to set the idle screw on the vaporizer a few turns richer (out) and allow the controller to control the emissions at idle, using the same oxygen sensor inputs as for cruise conditions.
  • this invention relates to a vaporizer apparatus suitable for use in fuel systems in accordance with the aforedescribed invention.
  • the main pressure reduction of the liquid is carried out in a first stage of the vaporizer.
  • the flow of vapour LPG to the engine may be controlled in a second stage of the vaporizer.
  • the vaporizer preferably includes an electronically controlled idle circuit, for connection to the controller as described above.
  • the idle circuit and the statutory gas lock on the LPG inlet are preferably controlled by an electronic safety switch that prevents the possibility of any LPG reaching the engine until the engine is being cranked.
  • the gas filter/lock off valves preferably communicate with a primary gas track through a primary valve held open by springs acting on a primary diaphragm, when the pressure in the primary gas track is low. As liquid LPG passes through the primary valve it will start to vaporise in the primary gas track as the pressure in this area is lower than the LPG cylinder pressure.
  • the pressure in the primary track may act on the underside of the primary diaphragm overcoming the primary diaphragm spring pressure and forcing the primary valve to close.
  • the primary pressure drops to between 22-26kPa the primary valve will again open. This is a continuous cycle of the primary regulator whilst operating the vaporizer.
  • the main function of the second stage regulator is to control the amount of vapour LPG being supplied to the engine depending on the engine demand. It works in conjunction with a mixer venturi which is positioned in the inlet air stream of the engine. At idle a secondary valve may be held closed by a sensitivity spring, idle gas flowing through the idle lock into the secondary chamber and through a gas outlet . As engine revs increase, a vacuum signal from the mixer (venturi) may be applied to the secondary chamber of the vaporizer. The pressure difference created, atmospheric on one side of the secondary diaphragm and venturi vacuum in the secondary chamber may acts on a secondary lever, opposing the sensitivity spring and opening the secondary valve allowing LPG vapour to be drawn into the engine .
  • the sensitivity spring adjustment is an important feature for providing preferred idle to part load progression.
  • the spring pressure must be light enough so that the secondary diaphragm can overcome the spring tension with very low vacuum signal which is produced at part load to prevent a flat spot or sluggish progression of idle, but there must be sufficient spring pressure to maintain proper sealing of the secondary valve seat to prevent LPG leaking through on engine shut down causing hard starting or in the worst scenario, the possibility of a fire.
  • both the LPG filter/lock and the idle lock solenoid When the ignition is switched on both the LPG filter/lock and the idle lock solenoid will be opened by the safety switch ( external ) between 0.5 and 3 seconds depending on where the safety switch is set.
  • This provides a small amount of LPG to prime the engine for easier starting and is similar in function to an automatic choke on a carburetor. If the prime time is too short, cranking time will be increased, if the prime time is too long the engine will flood and be hard to start.
  • both the LPG filter/lock and idle solenoid will remain open.
  • the LPG filter/lock and the idle solenoid are open and the secondary valve is closed so the amount of LPG required for idle flows through the idle circuit and is adjusted by an idle adjusting screw.
  • the mixer venturi is starting to generate a vacuum signal which will act on the secondary diaphragm and start to open the secondary valve.
  • the vacuum signal generated in the mixer venturi increases applying a greater vacuum to the secondary diaphragm opening the secondary valve further supplying more LPG vapour on engine demand.
  • the mixer venturi has now generated its maximum vacuum which is pulling the secondary diaphragm down, further increasing the opening on the secondary valve increasing the vapour flow through the primary gas track as this flow increases a vacuum is being produced below the primary diaphragm opening the primary valve further increasing the venturi signal on the boost tube and the vacuum on the primary diaphragm increasing flow through the primary gas track producing more LPG vapour supply to the gas outlet ensuring a richer mixture needed for maximum power.
  • FIG 1 is a section through vaporizer apparatus in accordance with the present invention
  • FIG 2 is a top view of the apparatus of FIG 1
  • FIG 3 is a partial section through a fuel system in accordance with the present invention.
  • a fuel system including a vaporizer of the 2 stage pressure reducing type which has a coolant system heat exchanger incorporated into its design.
  • the main functions of the vaporizer is to reduce the tank pressure (usually 0.3-1.3 MPa ) to a primary pressure of 14- l ⁇ kPa, to vaporise the liquid state of the LPG to vapour, and to control the flow of the vapour to the engine.
  • the main pressure reduction of the liquid is carried out in the first stage of the vaporizer ( 1 ) .
  • the flow of vapour LPG to the engine is controlled in the second stage of the vaporizer (2).
  • the heat exchange chamber which is connected to the engine cooling system, (usually to the cabin heater system). When installed correctly it will provide a good flow of hot coolant through the unit and the heat exchange plate will guarantee a complete and continuous vaporization of the LPG through the primary track (3).
  • the vaporizer also has a separate electronically controlled idle circuit (4), which with the gas lock (5), is controlled by an electronic safety switch (external device), that prevents the possibility of any LPG reaching the engine until the engine is being cranked.
  • the technical specifications of the illustrated vaporizer are as follows:
  • the liquid LPG After passing through the gas filter/lock off valve (5) the liquid LPG enters the 1st stage of the vaporizer, (the primary regulator) at the primary valve (6). While there is no pressure in the primary gas track ( 3 ) the primary valve ( 6 ) will be held open by spring pressure from the springs (8) acting on the primary diaphragm (9) and the primary pin (10).
  • the main function of the second stage regulator ( 2 ) is to control the amount of vapour LPG being supplied to the engine depending on the engine demand. It works in conjunction with a mixer venturi which is positioned in the inlet air stream of the engine. At idle the secondary valve (11) is held closed by the sensitivity spring (12), idle gas flows through the idle lock ( 13 ) into the secondary chamber and through the gas outlet (14). As engine revs increase, a vacuum signal from the mixer (venturi) is applied to the secondary chamber of the vaporizer (2).
  • the sensitivity spring adjustment (18) is most critical in the idle to part load progression.
  • the spring pressure must be light enough so that the secondary diaphragm can overcome the spring tension with very low vacuum signal which is produced at part load to prevent a flat spot or sluggish progression of idle, but there must be sufficient spring pressure to maintain proper sealing of the secondary valve seat to prevent LPG leaking through on engine shut down causing hard starting or in the worst scenario, the possibility of a fire.
  • both the LPG filter/lock ( 5 ) and the idle lock solenoid ( 13 ) will be opened by the safety switch (external) between 0.5 and 3 seconds depending on where the safety switch is set.
  • This provides a small amount of LPG to prime the engine for easier starting and is similar in function to an automatic choke on a carburetor. If the prime time is too short, cranking time will be increased, if the prime time is too long the engine will flood and be hard to start.
  • both the LPG filter/lock and idle solenoid will remain open.
  • the LPG filter/lock (5) and the idle solenoid (13) are open the secondary valve (11) is closed so the amount of LPG required for idle flows through the idle circuit sand is adjusted by the idle adjusting screw (21).
  • the mixer venturi When at idle on part load, the mixer venturi is starting to generate a vacuum signal which will act on the secondary diaphragm (15) and start to open the secondary valve (11). Under part load, the vacuum signal generated in the mixer venturi increases applying a greater vacuum ot the secondary diaphragm (15) opening the secondary valve (11) further supplying more LPG vapour on engine demand.
  • the mixer venturi has now generated its maximum vacuum which is pulling the secondary diaphragm (15) down, further increasing the opening on the secondary valve (11), increasing the vapour flow through the primary gas track (3), as this flow increases a vacuum is being produced below the primary diaphragm ( 9 ) , opening the primary valve ( 6 ) further increasing the venturi signal on the boost tube (17) and the vacuum on the primary diaphragm (9) increasing flow through the primary gas track ( 3 ) producing more LPG vapour supply to the gas outlet ( 14 ) ensuring a richer mixture needed for maximum power.
  • the throttle will be closed, all but cutting off the air flow to the engine. This will lessen the vacuum signal generated in the mixer allowing the sensitivity spring (12) pressure to return the secondary lever (16) and secondary valve (11) to the closed position so the only LPG vapour entering the engine now is the LPG from the idle circuit.
  • the gas outlet 14 from the vaporizer feeds gas to the engine via a feed pipe 30 having disposed therein a load block 31 having a gas passage therethrough.
  • the load block 31 mounts a power valve assembly 32 comprising a diaphragm 34 mounting a piston 33 and operable by application of vacuum through pipe 35. Adjustment is provided by adjusting knob 36 acting on adjusting shaft 37 engaging the piston 33.
  • a trim valve assembly 40 comprising a solenoid 41 operating a piston 42 operable to move towards and away from the face of the powervalve piston 33.
  • the trim piston 42 is biased out of engagement with the piston 33.
  • the solenoid 41 is operable by control cable 43 by controller 44, whereby the position of the trim piston 42 is regulated in response to input from an oxygen sensor 45 to the controller 44.
  • the controller 44 is also adapted to receive input from a throttle position sensor 46 whereby an idle condition may be detected. In response thereto, the controller pulses the idle solenoid 4 to achieve a selected result or range of oxygen values at the oxygen sensor 45.
  • the water jacket assembly of the vaporizer is able to be substituted by a heat tube. This has the advantage that the vaporizer can be converted with the substitution of a stainless steel tube to allow exhaust gas from the engine to heat the LP gas in place of the water system. This has advantages on air cooled engines.
  • the vacuum signal boost system of sensing the venturi effect through the secondary valve and using this signal to argument the bias of the primary diaphragm is unique in that both sides of the primary diaphragm are under control.
  • the lower surface has vacuum supplied by the boost tube exposed venturi style to the flow through the secondary seat and the upper surface of the diaphragm has spring pressure resisted by the vacuum being supplied by the engine. This has the effect of not allowing the springs to overexert their influence on the primary diaphragm in a rush thus choking the gas inlet system.
  • the secondary lever ratios are by design such that the travel of the diaphragm is transmitted to the secondary valve in such ration to be progressive with an acceleration ramp during the last stages of travel.
  • the modular system of construction of the vaporizers allows the modular conversion from LPG to CNG vaporizers with the inclusion or removal of items building block style.
  • all of the features as described are retained but with the removal of the water heating chamber and the insertion of a stainless tube through the heating tunnel. This tube is for exhaust gas to be directed through the vaporizer from the vehicle thus heating the vaporizer.
  • an added high pressure gas chamber may replace the primary diaphragm cover.
  • This chamber has incorporated a heating tube for the engine water which is all the heat needed to be supplied to a CNG vaporizer. The original water plate is removed. This in effect converts the vaporizer to a three stage vaporizer for CNG use.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)

Abstract

L'invention concerne un système de combustion qui comprend un vaporisateur à deux phases comportant une chambre d'échange thermique reliée au système de refroidissement du moteur, un circuit de ralenti (4) et un obturateur de gaz (5) commandé par un interrupteur de sécurité qui empêche le GPL d'atteindre le moteur tant que celui-ci n'a pas démarré. Un organe de commande, qui reçoit les gaz provenant du vaporisateur, comporte une unité support (31) sur laquelle est monté un ensemble de soupapes de puissance (32) comprenant un diaphragme (34) et un piston (33) et pouvant être actionné par l'application d'une dépression dans la tubulure. A l'opposé du piston (33) est monté un ensemble soupape d'équilibrage (40) comprenant un piston (42) actionné par un solénoïde, qui peut se rapprocher et s'éloigner du piston (33). Le solénoïde (41) est actionné par un organe de commande (44), la position de la soupape d'équilibrage étant régulée en réponse à un signal d'entrée provenant d'un capteur d'oxygène (45) et d'un capteur de position (46) du papillon, et destiné à l'organe de commande (44). En réponse à une condition de ralenti, l'organe de commande fournit des impulsions au solénoïde en position de repos (4), de façon que le capteur d'oxygène (45) atteigne une plage de valeurs sélectionnée.
PCT/AU1997/000776 1996-11-11 1997-11-11 Commande d'alimentation en carburant gazeux et vaporisateur de carburant WO1998021463A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU49348/97A AU4934897A (en) 1996-11-11 1997-11-11 Gaseous fuel supply control and fuel vaporiser

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AUPO3555 1996-11-11
AUPO3555A AUPO355596A0 (en) 1996-11-11 1996-11-11 Fuel system

Publications (2)

Publication Number Publication Date
WO1998021463A1 true WO1998021463A1 (fr) 1998-05-22
WO1998021463A9 WO1998021463A9 (fr) 1999-01-28

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AU (1) AUPO355596A0 (fr)
TW (1) TW394826B (fr)
WO (1) WO1998021463A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001034962A1 (fr) * 1999-11-09 2001-05-17 James Timothy Sangster Dispositif de vaporisation de combustible liquide pour moteurs a combustion interne et a injection
EP2899386A4 (fr) * 2012-09-21 2015-09-02 Yanmar Co Ltd Moteur à combustion interne

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4369751A (en) * 1980-08-13 1983-01-25 Ayres Technologies, Inc. Liquefied propane carburetor modification system
US4413607A (en) * 1980-08-13 1983-11-08 Batchelor William H Propane carburetion system
US5357938A (en) * 1990-04-20 1994-10-25 Green Power International Limited Exhaust emission control in gaseous fuelled engines
US5529048A (en) * 1991-04-20 1996-06-25 Yamaha Hatsudoki Kabushiki Kaisha Fuel control and feed system for gas fueled engine

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4369751A (en) * 1980-08-13 1983-01-25 Ayres Technologies, Inc. Liquefied propane carburetor modification system
US4413607A (en) * 1980-08-13 1983-11-08 Batchelor William H Propane carburetion system
US5357938A (en) * 1990-04-20 1994-10-25 Green Power International Limited Exhaust emission control in gaseous fuelled engines
US5529048A (en) * 1991-04-20 1996-06-25 Yamaha Hatsudoki Kabushiki Kaisha Fuel control and feed system for gas fueled engine

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001034962A1 (fr) * 1999-11-09 2001-05-17 James Timothy Sangster Dispositif de vaporisation de combustible liquide pour moteurs a combustion interne et a injection
EP2899386A4 (fr) * 2012-09-21 2015-09-02 Yanmar Co Ltd Moteur à combustion interne

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TW394826B (en) 2000-06-21

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