DE60314737T2 - FUEL INJECTION VALVE FOR AN INTERNAL COMBUSTION ENGINE - Google Patents

Abstract

A fuel injector for vaporizing a liquid fuel for use in an internal combustion engine. The fuel injector includes at least one capillary flow passage (12) , the at least one capillary flow passage (12) having an inlet end (14) and an outlet end (16), the capillary flow passage comprises a channel formed within a monolithic body produced from a material selected from the group consisting of ceramics, polymers, metals and composites thereof or a multi-layer ceramic body, a fluid control valve (18) for placing the inlet end of the at least one capillary flow passage (12) in fluid communication with the liquid fuel source and introducing the liquid fuel in a substantially liquid state, a heat source (20) arranged along the at least one capillary flow passage, the heat source (20) operable to heat the liquid fuel in the at least one capillary flow passage (12) to a level sufficient to change at least a portion thereof from the liquid state to a vapor state and deliver a stream of substantially vaporized fuel from the outlet end of the at least one capillary flow passage.

Description

The The present invention relates to fuel delivery in an internal combustion engine or an internal combustion engine. In particular, provide the procedure and the device according to this Invention for at least one heated capillary for vaporizing fuel supplied from an internal combustion engine.

It A variety of systems have been engineered to internal combustion engines fine drops of liquid To supply fuel and air. These systems lead either the fuel directly into the combustion chamber (direct injection) or use a carburetor or one or more fuel injectors or fuel injection valves to the mixture through an intake manifold in to conduct a combustion chamber (indirect injection). at currently used systems, the fuel / air mixture is generated by a liquid Fuel atomizes and when fine drops are introduced into a stream of air.

at usual Gasoline engines that inject fuel through a suction slot apply, the injected fuel is under normal operating conditions evaporates by adding the drops of liquid fuel to hot components in the intake or the manifold be directed. The liquid Fuel forms on the surfaces the hot ones Components a film and is then evaporated. The mixture Evaporated fuel and intake air is then affected by the pressure difference sucked into the cylinder, which arises when the intake valve opens and the piston moves to the bottom dead center. To the extent of control To secure, that is compatible with modern engines, this becomes Evaporation process is typically optimized to work in less than one engine cycle takes place.

at In most engine operating conditions, the temperature is sufficient of the aspirating components to the impinging drops of the liquid fuel to evaporate quickly. In conditions such as the cold start and the Warm-up, however, the fuel is due to the impact the relatively cold engine components are not evaporated. Instead the running of the engine is thereby ensured under these conditions that an excess of fuel is supplied, so that one sufficient share by the heat and vaporizes the mass transport as it flows through the air before he bounces on a cold intake component. The evaporation rate through this mechanism is a function of the properties of the Fuel, temperature, pressure, relative speeds of drops and air and the drop diameter. This method of course fails during cold starts in an extreme environment where the volatility of fuel is insufficient to ignite vapor in flammable To produce concentrations with air.

For the combustion to be chemically complete, the fuel / air mixture must be vaporized to a stoichiometric gas phase mixture. A combustible stoichiometric mixture contains the exact amounts of air (oxygen) and fuel required for complete combustion. For gasoline, this weight ratio of air / fuel is about 14.7: 1. A fuel / air mixture that is neither completely vaporized nor chemically stoichiometric results in incomplete combustion and lower thermal efficiency. The products of an ideal combustion process are water (H ₂ O) and carbon dioxide (CO ₂ ). When incineration is incomplete, part of the carbon is not completely oxidized, yielding carbon monoxide (CO) and unburned hydrocarbons (HC).

Of the Order to reduce air pollution has led to attempts that poor combustion due to a variety of modi fications of Fuel system and the engine to compensate. Like from the state technology, systems for preparation and promotion As far as fuel is concerned, a lot of effort has gone into it Reduction of the droplet size of the liquid fuel, a reinforcement of Turbulence in the system and the provision of sufficient heat for Vaporizing the fuels directed to a more complete To allow combustion.

A insufficient preparation of the fuel at lower engine temperatures remains a problem that leads to higher emissions, which means Aftertreatment and complex control strategies are required are. Such control strategies may include the recirculation of exhaust gas, a variable timing of the valves, a delayed temporal Control of the ignition, lower compression ratios, the Use of catalysts and the injection of air belong to unburned hydrocarbons to oxidize and an exothermic To cause reaction for the onset of the catalyst is advantageous.

Too much fuel for the engine during cold start and warm-up is in conventional engines A significant source of emissions in the form of unburned hydrocarbons. A compromise with this problem is that the catalyst is also cold during this period of operation, and thus does not reduce a significant amount of the unburned hydrocarbons passing through the exhaust of the engine. As a result, the high concentrations of unburned hydrocarbons emitted by the engine are essentially unreacted by the catalyst and are exhausted from the exhaust pipe. It has been estimated that 80% of the total hydrocarbon emissions produced by a typical modern automobile occur during the cold-start and warm-up periods when the engine is over-supplied with fuel and the catalyst is substantially inactive.

in view of of the relatively large Share of during unburned hydrocarbons released from the start Significant efforts in advancing this technology focused on this aspect of the operation of an automotive engine. In addition, ever stricter emission standards come into effect and Consumers continue for the price and the performance are sensitive, these development attempts remain of highest importance. These tests, the emissions of conventional engines at startup reduce generally in two categories: 1) the reduction of warm-up time for three-way catalyst systems and 2) improving the methods of vaporizing the fuel. To the attempts, the warm-up time for three-way catalysts To shorten, belong currently: a delay the timing of the ignition, to increase the exhaust gas temperature; the premature opening the exhaust valves; the electrical heating of the catalyst; the Heat the catalyst with a burner or a flame; and the catalytic Heat of the catalyst. Overall, these attempts are expensive and concern the HC emissions at or immediately after the cold start not.

It A variety of methods have been proposed that address the Turn to problem of evaporating fuel. To US patents, Propose the methods of vaporizing the fuel include: US patent No. 5,195,477, published for Hudson, Jr. et al., U.S. Patent No. 5,331,937, issued to Clarke, U.S. Patent No. 4,886,032, published for Asmus, U.S. Patent No. 4,955,351 for Lewis et al., U.S. Patent No. 4,458,655, issued to Oza, U.S. Patent No. 6,189,518, published for Cooke, U.S. Patent No. 5,482,023 for Hunt, U.S. Patent No. 6,109,247 for Hunt, U.S. Patent No. 6,067,970 for Awarzamani et al., U.S. Patent No. 5,947,091, issued to Krohn et al., U.S. Patent No. 5,758,826, issued to Nines, U.S. Patent No. 5,836,289 for Thring and U.S. Patent No. 5,813,388 for Cikanek, Jr. et al.

Other proposed fuel delivery devices include U.S. Patent No. 3,716,416, which discloses a fuel metering device for use in a fuel cell system. The fuel cell system is intended to be self-regulating, generating power at a predetermined value. The proposed fuel metering system includes a capillary flow regulator to throttle the fuel flow in response to the power output from the fuel cell, rather than providing better fuel preparation for subsequent combustion. The fuel should instead be supplied to the fuel cell for conversion to H ₂ . In a preferred embodiment, the capillary tubes are made of metal and the capillary itself is used as a resistor in electrical contact with the output power of the fuel cell. Since the flow resistance of steam is higher than that of a liquid, the flow is throttled as the output power increases. The fuels proposed for use include any fluid that readily changes from the liquid to the vapor phase when heat is applied and flows freely through a capillary. The vaporization is apparently achieved in a manner in which vapor trapping occurs in automotive engines.

US Patent No. 6,276,347 a supercritical or near supercritical atomizer and a Procedure before to atomize or vaporizing a liquid to reach. The supercritical atomizer of US Pat. No. 6,276,347 intended the use of high-boiling fuels for operation enable small lightweight tomotors with a low compression ratio, which typically burn petrol. The atomizer is supposed to make a spray fine drops of liquid or a fluid resembling Generate fuels by the fuels in the phase diagram, associated with these fuels, in the gas stability range brought in the direction of their supercritical temperature and into one Area can be released with lower pressure, resulting in fine Atomize or evaporating the fuel. The utility is for uses, like internal combustion engines, a scientific equipment that chemical treatment, the control of the disposal of waste, the Cleaning, etching, the Insect control, modification of surfaces, humidification and evaporation, disclosed.

To minimize decomposition, US Pat. No. 6,276,347 proposes to use the fuel under the super critical temperature until it passes through the rear end of a nebulization constriction. For certain applications it is necessary to heat just the top of the constriction to minimize the possibility of chemical reactions or precipitation. This is to alleviate problems associated with contaminants, reactants, or materials in the fuel stream that would otherwise be driven out of solution, clogging pipes and filters. Operating at or near supercritical pressure suggests that the fuel supply system operate in the range of 21.1 to 56.2 kg / cm ² (300 to 800 psig). Although the application of supercritical pressure and supercritical temperature may reduce clogging of the nebulizer, it appears to require the use of a relatively more expensive fuel pump, as well as fuel lines, fittings, and the like, which can operate at this elevated pressure.

EP 0 915 248 A1 suggests a fuel injector for use in the intake manifold of an internal combustion engine that uses LPG. The proposed device consists of an injector, whose body has a tip through which a fuel outlet, wherein it further consists of an injection tube which extends the tip of this injector and the channel is in line with the outlet hole, wherein the injection tube a cantilevered area extending into the intake manifold, as well as having means to prevent the formation of ice on this injection pipe at least partially prevented.

US Patent No. 5,873,354 suggests a fuel supply system for one Internal combustion engine, which has a metering device for the intake air, leading to individual combustion chambers, some fuel injectors, each of which is associated with a combustion chamber, and one central fuel evaporator, which the fuel through a separate fuel metering device can be supplied. It will be further suggested that the Fuel vapor of the intake air generated in the fuel evaporator for the Combustion chambers downstream the metering device for The intake air can be added to pollute emissions while to reduce the warm-up phase of the internal combustion engine after the start.

To In one aspect, the present invention relates to a fuel injector to evaporate a liquid Fuel for the use in an internal combustion engine according to claim 1.

To Another aspect relates to the present invention a fuel system for the use in an internal combustion engine according to claim 10.

To Another aspect relates to the present invention a method for supplying fuel to an internal combustion engine Claim 13.

The The present invention provides a fuel injector and a support system ready to deliver the vaporized fuel, with a minimum Performance and warm-up time are required without having a high-pressure fuel supply system required in a number of configurations can be, including traditional ones Engines with the injection of fuel through a suction slot, Hybrid electric motors, gasoline engines with direct injection and include alcohol-powered engines.

The Invention will now be described with reference to the preferred embodiments of the invention, given by way of example only, and by reference on the attached Drawings in more detail described, which show:

1 a modified fuel injector, partially in cross-section, including a capillary flow path according to a preferred form;

2 a side view of an embodiment of the fuel injection device according to another preferred form;

2A a true to scale view of the outlet of the capillary of 2 embodiment shown;

3 a side view of another embodiment of the fuel injection device according to another preferred form;

3A a true to scale view of another design of the outlet of the capillary of 3 embodiment shown;

4 a side view of another embodiment of the fuel injection device according to a preferred form;

4A a true to scale view of another design of the outlet of the capillary of 4 embodiment shown;

5 a schematic representation of another embodiment of a fuel injection device according to a preferred form;

6 a side view of another embodiment of a fuel injection device according to a preferred form;

7 a cross-section of another embodiment of the fuel injection device according to another preferred form;

8th a side view of another embodiment using two injectors, according to another preferred form;

9 a side view of another embodiment of a fuel injection device according to a preferred form, which is partially shown in cross section;

9A an enlarged view of the designated area of in 9 embodiment shown;

10 a side view of another embodiment of a fuel injection device according to a preferred form, which is partially shown in cross section;

10A an enlarged view of the designated area of in 10 embodiment shown;

11 a side view of another preferred form of a corresponding fuel injection device;

11A a true to scale view of another design of the outlet of the capillary of 11 illustrated embodiment;

12 a side view of another embodiment of a fuel injection device with a capillary flow path, which is heated with recirculated exhaust gas;

13 a schematic representation of the Kraftstofförder- and control system according to a preferred form;

14 a graphical representation of the engine parameters during the first 20 seconds of starting in an engine using the Kraftstoffördervorrichtung invention;

15 a graphical representation of a comparison of the engine emissions of Kraftstoffördervorrichtung invention with conventional injectors with a suction slot;

16 a graph of mass flow rate of gasoline as a function of time showing the advantage of the operation achieved by the use of the oxidizing cleaning method according to the present invention;

17 a graphical representation of the flow rate of the fuel over time for commercial grade gasoline;

18 a graphical representation of the flow rate of the fuel over time comparing different types of gasoline;

19 FIG. 4 is a graph of the fuel flow rate versus time comparing a jet fuel with No. 2 diesel fuel; FIG.

20 a graph of the flow rate of the fuel over time for a diesel fuel without additives, showing the effect of oxidative cleaning; and

21 FIG. 12 is a graph of the fuel flow rate versus time comparing a diesel fuel with no additives to a diesel fuel containing a soil-preventing additive. FIG.

Now on the in the 1 to 21 illustrated embodiments, wherein for the designation of similar parts throughout the same reference numerals are used.

The The present invention provides the preparation and promotion from fuel to that for Cold start, warm-up and normal operation of an internal combustion engine useful are. The fuel system includes a fuel injector with a capillary flow path one, the liquid one Heat fuel can, so in the cylinder of an engine substantially vaporized fuel introduced becomes. The substantially vaporized fuel can be compared with conventional Fuel injection systems burned at lower emissions become. The fuel supply system according to the invention requires as well less power or current and has shorter warm-up times than others Evaporation process.

in the Generally, gasolines do not evaporate at low temperatures light. In the cold start and warm-up period is a relatively low Evaporation of the liquid Fuel instead. That is why it is necessary for everyone Cylinder of the engine an excess of liquid fuel to achieve an air / fuel mixture, the burns. When igniting the fuel vapor resulting from this excess of liquid fuel, shut down the combustion gases emitted from the cylinders unburned fuel and unwanted gaseous Emissions. Upon reaching the normal operating temperature evaporates however the liquid one Fuel easily, so less Fuel is required to achieve an air / fuel mixture, that easily burns. Advantageously, when reaching the normal operating temperature the air / fuel mixture at or near the stoichiometric relationship be controlled, reducing emissions of unburned hydrocarbons and carbon monoxide are reduced. When the fuel delivery at or near the stoichiometric relationship is controlled, just is in the exhaust stream just enough air for the simultaneous oxidation of unburned hydrocarbons and Carbon monoxide and for the reduction of nitrogen oxides over the three-way catalyst (TWC) available.

By the system and method according to the present invention Invention will be fuel that has been substantially vaporized is in the intake flow path or injected directly into a cylinder of the engine, causing the Need for a fuel surplus during the Starting and warm-up period of a motor is eliminated. The fuel is the Motor preferably in a stoichiometric or low fuel mixture with air, or air and diluent, supplied so that in Cold start and warm-up period practically all the fuel is burned.

At the usual Injecting fuel through a suction slot is too much Fuel required to ensure robust, fast engine starts. Under fuel-rich conditions, it contains the three-way catalyst reaching exhaust gas flow insufficient air to the excess fuel and unburned hydrocarbons to oxidize when the Catalyst heated. An attempt to address this problem is to use it an air pump to additional Air in the exhaust stream upstream to introduce the catalyst. The task is a stoichiometric or low fuel To produce exhaust stream, which react on the catalyst surface can, once the catalyst has reached the temperature at he starts. In contrast, enable it is the system and method according to the present invention, that the Engine in cold start and warm-up period at stoichiometric or even light fuel-efficient conditions works, bringing both the need for a fuel surplus as well the need for additional Air pump for The exhaust gas is eliminated, reducing the cost and complexity of the aftertreatment system for the Remove the exhaust.

As noted, in the cold-start and warm-up period, the three-way catalyst is first cold and can not reduce a significant amount of unburned hydrocarbons passing through the catalyst. Efforts have been made to reduce the warm-up time for three-way catalysts to convert a greater proportion of the unburned hydrocarbons released during the cold-start and warm-up periods becomes. One such concept is to deliberately fuel the engine during the cold-start and warm-up periods. With an exhaust gas pump to introduce air into this high-fuel exhaust stream, a combustible mixture may be generated that is combusted either by auto-ignition or by some ignition source upstream of or inside the catalyst. The exotherm generated by this oxidation process significantly heats the exhaust gas and the heat is transferred to the catalyst as much as possible as the exhaust gas flows through the catalyst. Using the system and method of the present invention, the engine can be controlled to alternately fuel and fuel-operate the cylinders so that the same effect is achieved without, however, requiring an air pump. In a four-cylinder engine, for example, two cylinders can be operated fuel-rich during the cold start and warm-up period, so that unburned hydrocarbons are generated in the exhaust gas. The two remaining cylinders can be fueled during cold start and warm up to provide oxygen in the exhaust stream.

The System and method according to the present invention Invention can can also be used in gasoline engines with direct injection (GDI). In GDI engines, fuel is injected into the cylinder as a finely atomized spray injected, which evaporates and mixes with air, thereby preventing the ignition a premixed filling is generated from air and vaporized fuel. Today's GDI engines require a high pressure of the fuel to the fuel a spray to atomise. GDI engines operate in stratified charge mode at a part load to To reduce the pumping losses, the conventional engines with indirect Injection are intrinsic. A gasoline engine with stratified charge offers the possibility, for one better fuel economy and lower emissions to burn poor mixtures. Preferably In the combustion chamber, an altogether poor mixture is produced, at the time of ignition near the spark plug however, as stoichiometric or slightly fuel-rich controlled. The stoichiometric part therefore becomes light ignited and this ignites again the rest of the poor mixture. Although pumping losses reduced can be is the working window that is currently used for shift loading operation disposal stands, at low speeds of the engine and relatively low Loads of the engine limited. The limiting factors include one insufficient time for evaporation and mixing at higher engine speeds and insufficient mixing or poor utilization of the air at higher Loads. By providing vaporized fuel can the system and method according to the present invention Invention the working window for extend the stratified charge, which solves the problem this is associated with insufficient time for evaporation and mixing is. Advantageously, in contrast to conventional GDI fuel systems of the type used in the practice of this invention Fuel pressure can be reduced, bringing the total cost and the complexity of the fuel system.

The The invention provides a device for conveying fuel for a Internal combustion engine including: a Source of compressed liquid Fuel, the liquid Supplying fuel under pressure, at least one capillary flow path, the one with the source for liquid Fuel is connected, and a heat source that runs along the at least one capillary flow path is arranged. The heat source can be operated like this they will the liquid Fuel in the at least one Kapillarströmungsweg sufficiently heated so the existence Stream of substantially ver evaporated fuel is supplied. The fuel delivery device is preferably operated so that the flow of the vaporized Fuel during the start, warm-up and other operating conditions of the Internal combustion engine of one or more combustion chambers of a Internal combustion engine supplied becomes. if desired For example, the at least one capillary flow path may serve the engine to supply liquid fuel under normal operating conditions.

The Invention also provides a method to a combustion engine To supply fuel, which includes the following steps: the compressed liquid fuel becomes at least one capillary flow path supplied and the compressed liquid Fuel in the at least one capillary flow path is sufficiently heated, so that causes will that during the Starts, the warm-up and other operating conditions of the internal combustion engine at least one combustion chamber of an internal combustion engine, a stream supplied by vaporized fuel.

The fuel delivery system of the invention includes at least one capillary flow path through which compressed fuel flows prior to being injected into an engine for combustion. A capillary flow path has a hydraulic diameter that is less than 2 mm, preferably less than 1 mm, and more preferably less than 0.5 mm. The hydraulic diameter is used in the calculation of fluid flow through a fluid conveying element. The hydraulic diameter is defined as the flow area of the fluid conveying element divided by the perimeter of the continuous boundary of contact with the fluid (commonly referred to as the "wetted" perimeter). In the case of a fluid conveying element of circular cross section, when the element is fully perfused, the hydraulic radius is (πD ^2/4 ) / πD = D / 4. For the flow of fluids in non-circular fluid conveying elements, the hydraulic diameter is used. Based on the definition of the hydraulic radius, the diameter of a fluid conveying element having a circular cross section is four times its hydraulic radius. Thus, the hydraulic diameter is defined as four times the hydraulic radius.

Along of the capillary flow path will heat applied what causes that at least a part of the liquid Fuel entering the flow path gets converted into steam when passing through the flow path flows. The fuel leaves the capillary flow path as a vapor, optionally a small amount of heated liquid fuel contains which has not been evaporated. "In the essentially evaporated "means that at least 50% by volume of the liquid Fuel through the heat source vaporized, stronger preferably at least 70% and more preferably at least 80% of the liquid Fuel evaporates. Although it is due to the complex taking place physical effects can be problematic, a 100% evaporation to achieve that would be nevertheless a complete one Evaporation desired. These complex physical effects exclude variations in boiling point of the fuel, since the boiling point is pressure-dependent and the pressure in the capillary flow path can change. Although it is assumed that a essential part of the fuel when heated in the capillary flow path reached the boiling point, therefore, a part of the liquid fuel not heated enough so that it evaporates completely, as a result, a portion of the liquid fuel comes together with the vaporized fluid through the outlet of the capillary flow path.

The capillary size fluid flow path is preferably formed in a capillary body, such as a single or multi-layered metal, ceramic or glass body. The flow path has an enclosed volume which opens to an inlet and an outlet, either or both of which may be open to the outside of the capillary body or with another flow path in the same body or other body or with fittings can be connected or can. The heater may be formed from a part of the body, such as a section of a stainless steel tube, or the heater may be a single layer or a wire of resistance heating material contained in or on the capillary body. The fluid flow path may be of any shape that includes an enclosed volume that opens to an inlet and an outlet and through which fluid can flow. The fluid flow path may have any desired cross section, with a preferred cross section being a circle of equal diameter. Other cross-sections of the capillary fluid flow path include non-circular shapes, such as triangular, square, rectangular, oval, or other shapes, and the cross-section of the fluid flow path need not be uniform. The fluid flow path may be rectilinear or non-straight and may be a single fluid flow path or a multi-path fluid flow path. When the capillary flow path is formed by a metal capillary tube, the tube may have an inside diameter of from 0.01 to 3 mm, preferably from 0.1 to 1 mm, more preferably from 0.15 to 0.5 mm. In another embodiment, the capillary flow path may be defined by the cross-sectional area of the flow path which is ^{8x10 -5} to 7 mm ² , preferably ^{8x10 -3} to ^{8x10 -1} mm ^2, and more preferably 2 x 10 ^-3 to 2 × 10 ^-1 mm ² can be. Many combinations of a single or multiple capillaries, different pressures, different lengths of capillaries, amounts of heat supplied to the capillary, and different cross-sectional areas are suitable for a given application.

The liquid fuel may be supplied to the capillary flow path at a pressure of at least 0.7 kg / cm ² (10 psig), preferably at least 1.4 kg / cm ² (20 psig). When the capillary flow path is formed from the interior of a stainless steel tube having an inside diameter of about 0.020 cm (0.020 in) and a length of about 15.2 cm (6 in), the fuel is preferably added to the capillary flow path at a pressure of 7 kg / sec. cm ² (100 psig) or less to achieve the mass flow rate required for the stoichiometric start-up of a typical size automobile engine cylinder (of the order of 100 to 200 mg / s). The at least one capillary flow path provides a sufficient flow of substantially vaporized fuel so as to ensure a stoichiometric or near-stoichiometric mixture of fuel and air that can be ignited and burned in the cylinder (s) of an engine without undesirable large Quantities of unburned hydrocarbons or other emissions. The capillary tube is also characterized in that it has a low thermal inertia, so that the capillary flow path very rapidly, preferably within 2.0 seconds, more preferably within 0.5 second, and most preferably within 0.1 second, to the for the evaporation desired temperature can be brought, which is advantageous in applications that include the cold start of an engine. The low thermal inertia can also offer advantages in normal operation of the engine, for example, by improving the ability of the fuel delivery to respond to sudden changes in the required engine power.

At the Evaporation of the liquid Fuel in a heated capillary can Deposits of carbon and / or high-boiling hydrocarbons on the capillary walls collect, and the flow of fuel can be significantly restricted, what finally can lead to clogging of the capillary flow path. The rate at which these deposits accumulate is a function of Temperature of the capillary wall, the flow rate of the fuel and the fuel grade. It is believed that fuel additives in the Reduction of such deposits can be useful. Should However, constipation form, this constipation can Oxidizing the deposits are removed.

1 shows a fuel injection device according to the invention 10 for vaporizing a liquid fuel that has been withdrawn from a source of liquid fuel. The device 10 closes a capillary flow path 12 one, the one inlet side 14 and an outlet side 16 having. A fluid control valve 18 is provided to the inlet side 14 of the capillary flow path 12 in fluid communication with a liquid fuel source F and the liquid fuel in a substantially liquid state into the capillary flow path 12 introduce.

If preferred, the fluid control valve 18 from a solenoid 28 be operated. The solenoid 28 has windings 32 on that with an electrical connector 30 are connected. When the windings 32 are energized, the solenoid element 36 in the middle of the windings 32 drawn. When the electricity from the windings 32 is switched off, performs a spring 38 the Soleniodelement back to its original position. A nozzle cone 40 is with the solenoid element 36 connected. The movement of the solenoid element 36 by supplying electricity to the windings 32 causes the nozzle plug out of the hole 42 being pulled, bringing fuel through the hole 42 can flow.

Along the capillary flow path 12 is a heat source 20 arranged. It is particularly preferred, the heat source 20 to form by the capillary flow path 12 is made of a tube of a material having an electrical resistance, wherein a part of the Kapillarströmungswegs 12 a heating element forms when a power source at the connections 22 and 24 connected to the tube to pass current. The heat source 20 can then of course be operated so that the liquid fuel in the capillary flow path 12 is heated to a sufficient value so that at least a part thereof is transferred from the liquid state to the vapor state and from the outlet side 16 of the capillary flow path 12 a stream of substantially vaporized fuel is discharged.

The device 10 Also includes a debris removal device during operation of the device 10 have been formed. The device for removing deposits that in 1 is shown, includes a fluid control valve 18 , a heat source 20 and a control valve 26 for the oxidant, whereby the capillary flow path 12 is brought into fluid communication with a source of the oxidizing agent C. It will be understood that the oxidant control valve may be located at each end or near each end of the capillary flow path 12 may be or may be configured to be in fluid communication with each end of the capillary flow path 12 stands. When the oxidant control valve is at or near the outlet side 16 of the capillary flow path 12 then it serves to supply the source of oxidizer C in fluid communication with the outlet side 16 of the capillary flow path 12 bring to. During operation, the heat source 20 used the oxidant C in the capillary flow path 12 to heat to a sufficient value, so that the deposits formed during the heating of the liquid fuel F oxidize. To switch from the fuel delivery mode to the cleaning mode, the control valve 26 for the oxidizing agent according to an embodiment are operated so that between the introduction of liquid fuel F and the introduction of the oxidant C in the Kapillarströmungsweg 12 is changed and the cleaning of the capillary flow path 12 in situ, when the oxidant is introduced into the at least one capillary flow path.

One method of oxidizing deposits involves passing air or vapor through the capillary. The flow path is preferably heated during the cleaning process so that the oxidation process is initiated and maintained until the deposits are exhausted. To improve this purification process, a catalytic substance can be used either as a coating on or as a component of the capillary wall to reduce the temperature and / or time required to perform the purification. For the continuous operation of the Kraftstofförder more than one capillary flow path may be used such that fuel flow, for example, when a clogging condition is detected by use of a sensor, may be diverted to another capillary flow path and the stream of oxidant may be introduced through the clogged capillary flow path to be cleaned. As an example, a capillary body may internally include a plurality of capillary flow paths, and a valve control arrangement may be provided to selectively supply each liquid flow path to liquid fuel or air.

To another embodiment The fuel flow may be at predetermined intervals from one capillary diverted and an oxidant stream are introduced. The fuel delivery to a capillary flow path can be effected by a regulator. The regulator may e.g. the fuel delivery for one activate predetermined period and fuel delivery disable after a specified period of time. The controller can open the basis of one or more established conditions also one Setting the pressure, the liquid Fuel and / or the Kapillarströmungsweg supplied amount of heat make. To the gathered Conditions include among others: the fuel pressure; the temperature of the capillary; and the air / fuel mixture. The controller may also have multiple fuel delivery devices control associated with this application. The regulator can also control one or more capillary flow paths to deposits or to remove blockages from it. The cleaning of a capillary flow path can e.g. by supplying heat to the capillary flow path and the capillary flow path is supplied with a current from an oxidant source.

The heated capillary flow path 12 For example, according to this invention, it may generate a stream of vaporized fuel that condenses in air, forming a mixture of vaporized fuel, fuel droplets, and air, commonly referred to as an aerosol. In comparison with a conventional device for injecting fuel through a motor vehicle intake slot providing a fuel spray composed of Sauter Mean Diameter (SMD) drops in the range of 150 to 200 μm, the aerosol has a mean droplet size SMD of less than 25 microns, preferably less than 15 microns. Thus, most of the fuel droplets generated by the heated capillary according to this invention can be carried by an air flow into the combustion chamber independently of the flow path.

Of the Difference between the drop size distribution of a conventional Injection device and the heated Kapillarströmungsweg invention is especially in conditions of cold start and warm-up critical. If a conventional Device for injecting fuel through a suction slot is used in particular the relatively cold components of the intake manifold a lot of fuel so that a sufficient portion of the big fuel drops, the on the manifold components bounce, evaporate, so that a ignitable Fuel / air mixture is generated. Conversely, the vaporized Fuel and the fine droplets caused by the fuel injection device according to the invention are generated substantially not by the temperature of the engine components influenced at start, and thus omitted the required excessive fuel production while the starting conditions of the engine. The elimination of excessive fuel supply in combination with a more precise control of the air / fuel ratio for the Engine, by the use of the heated capillary injector according to the invention is achieved leads to significantly lower emissions during cold start compared with those produced by engines, the conventional fuel injection systems use. additionally to reduce excessive fuel production It should also be stressed that the heated capillary injection device according to the invention Furthermore, during cold start and warm-up a fuel-lean Operation allows what a stronger one Reducing emissions at the exhaust pipe leads when the catalyst heated.

See further 1 ; the capillary flow path 12 For example, a metal tube, such as a stainless steel capillary tube, and the heater may comprise a length of the tube 20 which passes through the electric current. In a preferred embodiment, the capillary tube is provided with an inside diameter of about 0.050 to 0.030 inches (0.051 to 0.076 cm), a heated length of about 5.0 to 25 inches (2 to 10 inches), and the fuel may be in the tube 12 at a pressure of less than 7.0 kg / cm ² (100 psig), preferably less than 4.9 kg / cm ² (70 psig), more preferably less than 4.2 kg / cm ² (60 psig), and still more preferably less than 3.1 kg / cm ² (45 psig) or less. It has been found that this embodiment produces ver vaporized fuel which forms a distribution of aerosol droplets whose size SMD is largely in the range of 2 to 30 microns, wherein the average droplet size SMD is about 5 to 15 microns, when the evaporated fuel at Ambient temperature condensed in air. The preferred size of the fuel droplets to achieve fast and near complete vaporization at cold start temperatures is less than about 25 microns. This result can be achieved when electric current is 10.2 to 40.8 kg / s (100 to 400 W), eg 20.4 kg / s (200 W), which is 2 to 3% of the energy content of the vaporized fuel, to a capillary tube made of stainless steel with 6 inches. The electrical current may be applied to the capillary tube when the tube is made entirely of an electrically conductive material, such as stainless steel, or a conductive material is provided on at least a portion of a non-electrically conductive tube or laminate having a flow path therein by For example, a material with an electrical resistance is laminated or applied, so that a resistance heater is formed on the tube or laminate. Electrical leads may be connected to the electrically conductive material to provide electrical power to the heater to heat the tube along its length. Embodiments for heating the tube along its length may include induction heating, eg, by an electrical coil disposed around the flow path, or other heat sources positioned relative to the flow path, such that the length of the flow path is conduction, convection, or radiant heat transfer or any combination thereof is heated.

Even though a preferred capillary tube a heated one length of about 15.2 cm (6 inches) and an inside diameter of about 0.051 cm (0.020 in) provide other configurations of capillaries an acceptable steam quality. The inner diameter may e.g. in the range of 0.05 to 0.08 cm (0.02 to 0.03 in), and the heated one Area of the capillary tube can range from 2.5 to 25.4 cm (1 to 10 in). It is not required, the capillary tube after the cold start and to warm up the warm-up, so that unheated capillary can be used to operate at normal temperature Motor adequately fluid To supply fuel.

Of the vaporized fuel leaving the fuel capillary according to the invention can in the same place as existing injectors for fuel through a suction slot or elsewhere along the Intake manifold in the intake manifold of a Motors are injected. However, if desired, the fuel capillary can be arranged so that they vaporized fuel directly into each cylinder of the engine supplies. The fuel capillary offers an advantage over systems the larger fuel drops produce when starting the engine on the back a sealed intake valve must be sprayed. Similar to the arrangement the outlets from conventional Fuel injectors is the outlet of the fuel capillary tube preferably flush with the wall of the intake manifold.

About 20 seconds (or preferably less) after the engine starts, the heat for the capillary flow path 12 shut off and the injection of liquid for normal operation of the engine can be started, using conventional fuel injection device are used. Normal operation of the engine may alternatively be by injecting liquid fuel via continuous injection or possibly pulsed injection through a non-heated capillary flow path 12 respectively.

In 2 a second embodiment of the present invention is shown. A fuel injector 100 has a capillary flow path 112 on. The capillary flow path 112 is along the heated length 120 heated. To the capillary flow path 112 is a flattened end 150 with a variety of perforations 152 in a plate 154 attached, the flattened end 150 covered as it is in 2A is shown. The fuel injection device 100 may be a fluid control valve, such as a solenoid valve of the type described above and in 1 type shown, the promotion of compressed liquid fuel to the capillary flow path 112 allows. After the motor is sufficiently heated, heating of the capillary flow path may occur 112 and liquid fuel can pass through the capillary flow path 112 be supplied.

In 3 a third embodiment of the present invention is shown. It is a fuel injection device 200 shown a capillary flow path 212 having. The capillary flow path 212 is along the heated length 220 heated. To the capillary flow path 212 is a shallow end 250 with a variety of perforations 252 in a plate 254 attached to the flat end 250 covered as it is in 3A is shown. The fuel injection device 200 may be a fluid control valve, such as a solenoid valve of the type described above and in 1 type shown, the promotion of compressed liquid fuel to the capillary flow path 212 allows. As described above, after the engine using a plurality of fuel injectors 200 has been started, the heating of the capillary flow path 212 and through the capillary flow path 212 can be supplied liquid fuel. The injector 200 can be advantageously purified by the use of the oxidation technique described above.

In 4 a fourth embodiment of the present invention is shown. It is a fuel injection device 300 shown having a Kapillarströmungsweg 312 having. The capillary flow path 312 is along the heated length 320 heated. To the capillary flow path 312 is a conical end 350 with a variety of perforations 352 in a conical plate 354 attached to the conical end 350 covered as it is in 4A is shown. The fuel injection device 300 may be a fluid control valve, such as a solenoid valve of the type described above and in 1 type shown, the promotion of compressed liquid fuel to the capillary flow path 312 allows. As described above, after the engine using a plurality of fuel injectors 300 has been started, the heating of the capillary flow path 312 and through the capillary flow path 212 can be supplied liquid fuel. The injector 300 can be advantageously purified by the use of the oxidation technique described above.

In 5 is a dual fuel injector 400 represented according to the present invention. 5 shows the fuel injection device 400 with dual function, which is a fuel injector 460 of the conventional type and a heated capillary injector 410 may include. In this embodiment, a heated capillary flow path 412 in the fuel injection device 400 integrated. About 20 seconds after starting the engine, or preferably less, the capillary injector can 410 by a solenoid operated piston 436. be deactivated and for the further operation of the engine, the conventional injection device 460 by another solenoid operated piston 470 to be activated.

Another embodiment of the present invention is in 6 shown. As shown there, to a fuel injector 500 a heated capillary flow path 512 and an injection nozzle 560 be mounted for liquid fuel. The fuel flow may be selective to the heated capillary flow path 512 to provide vaporized fuel or to the nozzle 560 be aligned so that liquid fuel is provided by the valve control arrangement 540 is applied as they are in 6 is shown. Approximately 20 seconds after the start of the engine, or preferably less, the fuel flow for normal operation of the engine may be through the valve control assembly 540 from the capillary flow path 512 to the nozzle 560 be switched for the liquid flow. The valve control arrangement 540 can be operated by a regulator that forms part of the engine's electronic control system.

In 7 another embodiment of the present invention is shown. A fuel injector 600 has a helical heated capillary flow path 612 on the inside of the fuel injector 600 as winding, as it runs in 7 is shown. In this embodiment, the capillary flow path is 612 around the solenoid assembly 628 wrapped and is along the heated length 620 heated by the electrical connections 622 and 624 is defined. This embodiment is useful in a case where space is limited and a linear capillary tube is inconceivable. In addition, this embodiment may be intended for use with a conventional fuel injector (see 8th ) to supply fuel to an engine under normal operating conditions.

See now 8th ; to a suction port 700 of the engine are a heated capillary injector 10 (of the basis of 1 described type) and a conventional injection device 750 appropriate for liquid fuel. In this embodiment, during cold start and warm-up of the engine, the fuel passes the engine through the capillary flow path 12 fed along its length 20 is heated. After the first approximately 20 seconds from the start of the engine, or preferably less, the heated capillary injector becomes 10 deactivated and the conventional fuel injection device 750 activated for normal operation of the engine.

It is to be understood that the apparatus and system for preparing and supplying fuel contained in the 1 to 4 and 7 can also be used in conjunction with another embodiment of the present invention. See again 1 ; the device for removing deposits includes: a fluid control valve 28 , a solvent control valve 26 for the fluid connection of the capillary flow path 12 with a solvent, a solvent control valve 26 located at one end of the capillary flow path 12 located. According to one embodiment of the device which utilizes cleaning with a solvent, the solvent control valve may 26 (The control valve for the oxidizing agent in the preferred form, which uses the oxidation purification method, as described above) are operated so that between the introduction of liquid Fuel and introducing solvent into the capillary flow path 12 is changed, thereby cleaning the capillary flow path 12 in situ is possible when the solvent is in the capillary flow path 12 is introduced. Although a variety of solvents may be used, the solvent may include liquid fuel from the liquid fuel source. If this is the case, no solvent control valve is required because there is no need to switch between fuel and solvent, and the heat source should be used when cleaning the capillary flow path 12 be deactivated.

Another embodiment of the present invention is in 9 partially shown in cross-section. In 9 is a fuel injection device 800 with a heated capillary flow tube 812 shown for the promotion of fuel to an internal combustion engine. Details of the tube for the promotion of fuel to an internal combustion engine are in 9A shown. As shown, there is an axially movable rod 850 inside the capillary flow path 812 , The front end 816 of the capillary flow path 812 is flattened, and the front end 852 of the axially movable rod 850 is conical, so that a valve 854 is formed, wherein the axial movement of the rod 850 the valve 854 opens and closes. It is understood that the repeated movement of the axially movable rod 850 causes the grinding of deposits that have been formed during operation of the fuel injection device according to the invention.

In 10 For example, another embodiment of the present invention is shown partially in cross-section. In 10 is a fuel injection device 900 with a heated capillary flow tube 912 shown for the promotion of fuel to an internal combustion engine. Details of the tube for the promotion of fuel to an internal combustion engine are in 10A shown. As shown, there is an axially movable rod 950 inside the capillary flow path 912 , The front end 916 of the capillary flow path 912 is flattened, and the front end 952 of the axially movable rod 950 is conical, so that a valve 954 is formed, wherein the axial movement of the rod 950 the valve 954 opens and closes. Inside the capillary flow path 912 There is also a variety of brushes 960 along the axially movable rod 950 are arranged to the capillary flow path 912 to clean. It is understood that the repeated movement of the axially movable rod 950 causes the grinding of deposits that have been formed during operation of the fuel injection device according to the invention.

In 11 is a further embodiment of the present invention partially shown in cross section. A fuel injector 1000 has a variety of capillaries 1012 arranged in parallel to supply fuel to an internal combustion engine. In this embodiment, the fuel is supplied to the engine through one or more capillary flow paths during certain periods of engine operation 1012 that go along their length 1020 are heated (eg cold start, warm-up and acceleration conditions). Since less vaporized fuel is required to reduce the unburned hydrocarbons, heat for one or more capillaries can be shut off in this configuration.

12 shows in simplified form how a fuel injector 10 that has a capillary flow path 12 can be arranged so that the liquid fuel flowing through it can be heated by using recirculated exhaust gas (EGR) to an elevated temperature, whereby the power requirement of the resistance heating means evaporating the fuel 20 is reduced. As shown, the capillary flow path is continuous 12 for heating by the EGR flow path 1100 , For the first start of the engine, the resistance heater 20 forming a portion of the capillary flow path 12 or a separate resistance heater, connected to a power source, such as a battery, to initially vaporize the liquid fuel F. After about 20 seconds of operation, the capillary flow path may become 12 be heated by the heat of the EGR, which otherwise by the resistance heater 20 required for the continuous evaporation of the fuel stream is reduced. Consequently, the fuel in the capillary flow path 12 evaporates the who, without the resistance heater 20 is used so that power can be saved.

13 shows an example of a control system 2000 schematically, which is used to an internal combustion engine 2110 to actuate a valve 2220 for the supply of liquid fuel in fluid communication with a source 2010 for liquid fuel and an injection path 2260 for liquid fuel, a valve 2210 for the supply of vaporized fuel in fluid communication with a source 2010 for liquid fuel and capillary flow paths 2080 and a valve 2020 for the supply of oxidizing gas in fluid communication with a source 2070 for oxidizing gas and capillary flow paths 2080 contains. The control system closes a regulator 2050 a, typically a plurality of input signals from egg ner variety of sensors of the engine receives, as from the sensor 2060 for the motor speed, the thermocouple 2062 for the air of the intake manifold, the sensor 2064 for the temperature of the coolant, the sensor 2150 for the ratio of air / fuel in the exhaust gas, the Kraftstofförderdruck 2012 etc. During operation, the controller performs 2050 a control algorithm based on one or more input signals and then generates an output signal 2024 for the valve 2020 for the supply of oxidant to purify clogged capillary flow paths according to this invention, an output signal 2040 for the valve 2220 for the supply of liquid fuel, an output signal 2034 for the valve 2210 for the supply of vaporized fuel and a command 2044 for the heating power to the power source, which is the heat for the capillaries 2080 supplies.

In operation, the system of the present invention may be configured so that the heat generated by the combustion is recirculated by utilizing the exhaust gas recirculation so that the liquid fuel is sufficiently heated to substantially vaporize the liquid fuel as it passes through the exhaust gas capillary flow 2080 passes, whereby the required electrical or otherwise heating the Kapillarströmungswege 2080 reduced or eliminated or supplemented.

EXAMPLES

EXAMPLE 1

It tests were carried out where jet fuel JP 8 was vaporized by adding the fuel with a micro-diaphragm pump system constant pressure of a heated Capillary flow was supplied. In these tests, capillary tubes with different Diameter and different length used. The tubes passed stainless steel 304 with a length of 2.5 to 7.6 cm (1 to 3 in) and an inner diameter (ID) and an outer diameter (OD) in cm (in) as follows: 0.025 ID / 0.046 OD (0.010 ID / 0.018 OD), 0.033 ID / 0.083 OD (0.013 ID / 0.033 OD) and 0.043 ID / 0.064 OD (0.017 OD) ID / 0.025 OD). The heat to evaporate the liquid Fuel was generated by passing electric current through a Part of the metal tube was conducted. The drop size distribution was measured with a laser diffraction system Spray-Tech by Malvern is made. There were drops with a medium Diameter to Sauter (SMD) of 1.7 to 4.0 microns produced. SMD is the diameter a drop whose surface / volume ratio is the same that of the entire spray is, and relates to the mass transport properties of the spray.

EXAMPLE 2

It Again tests were carried out with gasoline that was vaporized by the fuel with a micro-diaphragm pump system at constant Pressure a heated capillary was supplied. In these tests, capillary flow paths were different Diameter and different length used. The following Table shows the empirical findings for different configurations the capillary tube.

EXAMPLE 3

In tests on a Ford 4.6-liter V8 engine, a group of four cylinders were modified to incorporate the fuel delivery devices of the present invention as described in U.S. Pat 1 are shown. The capillary heaters were mounted with the tip of the capillary flush with the wall of the suction port, that is the location of the fuel supply injector. These tests were done with continuous injection (100% duty cycle), and thus the fuel pressure was used to control the flow rate of the fuel vapor.

Please refer 14 ; the graph shows the results of the capillary device for delivering fuel during the first 20 seconds of cold start of an engine. The drawn line 1 is the speed of the motor in revolutions per minute as time passes along the x-axis. The drawn line 2 represents the flow of fuel in grams per second as time passes along the x-axis. The drawn line 3 stands for lambda when the time runs along the x-axis, where the unit lambda indicates the stoichiometric ratio between air and fuel. The drawn line 4 represents the total emitted hydrocarbon emissions, equivalent to methane per million, from the exhaust of an engine as time passes along the x-axis.

Like the drawn line 3 in 14 shows, the initial too much fuel required for the basic components of an engine and the control strategy has been eliminated by the use of the fuel delivery device according to the present invention. That is, the fuel delivery device of the present invention effectively vaporizes liquid fuel during the first starting period, so that the engine has been started at a near-stoichiometric air-fuel ratio. 15 FIG. 12 is a graph showing the reduction in emissions resulting from the near-stoichiometric start achieved with the fuel delivery device of the present invention (shown in FIG 6 ), compared with the conventional starting strategy with too much fuel (line drawn 5 ) explained. In particular, the results show in 15 in that the fuel delivery device according to the invention reduces the associated hydrocarbon emissions by 46% during the first 10 seconds of cold start compared to the basic configuration requiring too much fuel. The one with the circle 7 indicated area shows the significant reduction of hydrocarbon emissions during the first 4 seconds of starting the engine.

EXAMPLE 4

Tests have been performed to demonstrate the benefits of the oxidative cleaning process in a heated capillary flow path using sulfur-free base gasoline without additives, which is known to form large amounts of scale. The capillary flow path used for these tests was a 5.1 cm (2 in) long heated capillary tube made of stainless steel with an inside diameter of 0.023 cm (0.023 in). The fuel pressure was maintained at 0.7 kg / cm ² (10 psig). Current was supplied to the capillary to achieve different values of R / R ₀ , where R is the resistance of the heated capillary and R _{0 is} the resistance of the capillary at ambient conditions.

16 shows a graphical representation of the flow rate of the fuel over time. As can be seen, this gasoline, containing no detergent additive, exhibited significant blockage within a very short period of time, with a 50% decrease in flow rate being observed in only 10 minutes.

After a significant blockage had occurred, fuel flow was discontinued and replaced with air at 0.7 kg / cm ² (10 psig). During this period, heating was provided and only 1 minute later significant clearing had been achieved, with flow rates returning to the previous levels.

EXAMPLE 5

This example shows that clogging in the heated capillary flow path of Example 4 is much less problematic when using a commercial gasoline grade that uses an effective additive package. As in 17 For example, after operation of the device for nearly 5 hours, a reduction in fuel flow rate of less than 10% has occurred.

EXAMPLE 6

Around various gasolines and the influence of the detergent additives on To compare the clogging, one let 5 test fuels in heated capillary of Example 4 flow. The tested fuels included a base gasoline without additives, containing 300 ppm of sulfur, a base gasoline without additives that does not contain sulfur, the Sulfur-free base gasoline with an added commercial additive (Additive A) and the sulfur-free base gasoline with another added commercial Additive (additive B).

As in 18 As shown, the fuels provided with additives acted similarly, whereas in the case of the fuels without additives, a significant blockage occurred during operation of less than 1 hour.

EXAMPLE 7

This example compares operation of a capillary flow path over time operating with a jet fuel without additives (JP-8) with the same capillary flow path operating with diesel fuel # 2 without additives when operating in a capillary flow path with an ID of 0.036 cm (0.014 in) and a length of 5.1 cm (2 in). Fuel pressure was set at 1.1 kg / cm ² (15 psig). Current was supplied to the capillary to reach a value of R / R _o of 1.19, where R is the resistance of the heated capillary and R _{0 is} the resistance of the capillary at ambient conditions.

As in 19 During the first 10 minutes of operation, the fuels operated similarly, with the diesel fuel showing a more pronounced clogging thereafter.

EXAMPLE 8

Tests were conducted to evaluate the effectiveness of the oxidative cleaning process on a heated capillary flow path, using No. 2 diesel fuel with no additives known to form large amounts of scale. The capillary flow path used for these tests was a 5.1 cm (2 in) long heated capillary tube constructed of stainless steel with an inside diameter of 0.036 cm (0.014 in). The fuel pressure was maintained at 1.1 kg / cm ² (15 psig). The capillary was energized to reach R / R ₀ of 1.19, where R is again the heated capillary resistance and R _{0 is} the capillary resistance at ambient conditions.

20 shows a graphical representation of the flow rate of the fuel over time. As can be seen, this fuel, which contained no detergent additive, exhibited significant clogging within a very short period of time, with a 50% flow rate decrease observed with continuous operation of about 35 minutes.

In a second attempt, after five minutes of operation, fuel flow was discontinued and replaced by air at 0.7 kg / cm ² (10 psig) for a period of 5 minutes. Heating was also provided during this period. This procedure was repeated every 5 minutes. As in 20 In fact, the oxidative purification process actually increased the flow rate of the fuel in any event and tended to slow down the overall reduction in fuel flow rate over time. However, the effectiveness of the process was somewhat lower than that achieved with gasoline without additives as described in Example 4.

EXAMPLE 9

Tests were conducted to assess the influence of a commercial antifouling detergent additive mixed with diesel fuel # 2 of Example g on the flow rate of fuel over time in a heated capillary flow path. Again, the capillary flow path used for these tests was a 5.1 cm (2 in) long heated capillary tube constructed of stainless steel with an inside diameter of 0.036 cm (0.014 in). Fuel pressure was maintained at 1.1 kg / cm ² (15 psig) and power was supplied to the capillary to achieve R / R ₀ of 1.19.

21 FIG. 12 shows a comparison of the fuel flow rate versus time for diesel fuel # 2 with additives and a diesel fuel with no additives. FIG. As shown, the fuel that did not occur Detergent additive contained a significant blockage within a very short period of time, with a 50% flow rate decrease observed with continuous operation in about 35 minutes, while the same base fuel containing the detergent extended well over a longer period of time showed less constipation.

Even though the invention in the drawings and the foregoing description in detail explained and U.S. Patent Nos. 5,230,730, 4,130,199, 4,130,148, 4,130,759, 4,130,759, and 4,130,130, the disclosed embodiments are only explanatory and not restrictive. All changes and modification which are within the scope of the invention should be protected. As an example, a plurality of capillary flow paths be provided with the fuel in parallel through the flow paths is conducted when a higher volumetric throughput desired is.

Claims (14)

Fuel injection device ( 10 ) for vaporizing a liquid fuel for use in an internal combustion engine, comprising: (a) at least one capillary flow path (14); 12 ), wherein the at least one capillary flow path ( 12 ) has a hydraulic diameter of less than 2 mm, an inlet side ( 14 ) and an outlet side ( 16 ), wherein the capillary flow path ( 12 ) has a channel formed in a monolithic body made of a material selected from the group of ceramics, polymers, metals and composites thereof or a multilayer ceramic body; (b) a fluid control valve ( 18 ) to the inlet side ( 14 ) of the at least one capillary flow path ( 12 ) in fluid communication with the liquid fuel source (F) and introducing the liquid fuel in a substantially liquid state; (c) a heat source ( 20 ) along the at least one capillary flow path (FIG. 12 ), the heat source ( 20 ) can be operated so that the liquid fuel in the at least one Kapillarströmungsweg ( 12 ) is heated to a sufficient value, so that at least a part thereof from the liquid state to the vapor state passes and from the outlet side ( 16 ) of the at least one capillary flow path ( 12 ) is discharged a stream of substantially vaporized fuel; and (d) means for removing deposits generated during operation of the fuel injector (10). 10 ), wherein the means for removing deposits the fluid control valve ( 18 ), wherein the fluid control valve ( 18 ) can be operated so that it at least one Kapillarströmungsweg ( 12 ) in fluid communication with a solvent, whereby the cleaning of the capillary flow path ( 12 ) is possible in situ when the solvent in the at least one Kapillarströmungsweg ( 12 ) is introduced. Fuel injection device according to claim 1, wherein the capillary flow path ( 12 ) is formed in a ceramic body. Fuel injection device according to claim 1 or 2, wherein the device for removing deposits, the fluid control valve ( 18 ) and a solvent control valve ( 26 ) to the. at least one capillary flow path ( 12 ) in fluid communication with a solvent, wherein the solvent control valve ( 26 ) at one end of the at least one capillary flow path ( 12 ) and wherein the solvent control valve ( 26 ) for the fluid connection of the at least one capillary flow path ( 12 ) can be operated with a solvent such that it can be operated between the introduction of liquid fuel and the introduction of solvent into the Kapillarströmungsweg ( 12 ) and the in situ cleaning of the capillary flow path ( 12 ) is possible, when the solvent in the at least one Kapillarströmungsweg ( 12 ) is introduced. A fuel injector according to any one of the preceding claims, wherein the solvent comprises liquid fuel from the source (F) of liquid fuel and wherein the heat source ( 20 ) during the cleaning of the capillary flow path ( 12 ) is gradually taken out of service. Fuel injection device according to one of the preceding claims, further comprising a nozzle ( 560 ) for atomizing a portion of the liquid fuel. Fuel injection device according to one of the preceding claims, further comprising a solenoid ( 28 ) to the liquid control valve ( 18 ), so that the inlet side ( 14 ) is brought into fluid communication with the liquid fuel source (F). Fuel injection device according to one of the preceding claims, wherein the Flüssigkeitsregelven til ( 18 ) a solenoid-operated valve stem with a valve element on the outlet side ( 16 ) of the at least one capillary flow path ( 12 ) to the outlet side ( 16 ) of the at least one capillary flow path ( 12 ) to open and close. Fuel injection device according to one of the preceding Claims, further comprising a non-capillary liquid fuel flow path, wherein this non-capillary flow path for liquid fuel an inlet side and an outlet side has, with the inlet side is in fluid communication with the liquid fuel source (F), wherein the non-capillary flow path for liquid fuel at the outlet side one fuel Injector having. Fuel injection device according to one of the preceding claims, wherein the heat source ( 20 ) includes a resistance heater. A fuel system for use in an internal combustion engine, comprising: (a) a plurality of fuel injectors ( 10 ), each injection device ( 10 ) includes (i) at least one capillary flow path ( 12 ), wherein the at least one capillary flow path ( 12 ) has a hydraulic diameter of less than 2 mm, an inlet side ( 14 ) and an outlet side ( 16 ), wherein the capillary flow path ( 12 ) has a channel formed in a monolithic body made of a material selected from the group of ceramics, polymers, metals and composites thereof or a multilayer ceramic body; (ii) a fluid control valve ( 18 ) to the inlet side ( 14 ) of the at least one capillary flow path ( 12 ) in fluid communication with the liquid fuel source (F) and introducing the liquid fuel in a substantially liquid state; (iii) a heat source ( 20 ) along the at least one capillary flow path (FIG. 12 ), the heat source ( 20 ) can be operated so that the liquid fuel in the at least Kapillarströmungsweg ( 12 ) is heated to a sufficient value, so that at least a part thereof from the liquid state to the vapor state passes and from the outlet side ( 16 ) of the at least one capillary flow path ( 12 ) is discharged a stream of substantially vaporized fuel; and (iv) means for removing deposits generated during operation of the fuel injectors ( 10 ), wherein the means for removing deposits the fluid control valve ( 18 ), wherein the fluid control valve ( 18 ) can be operated so that it at least one Kapillarströmungsweg ( 12 ) in fluid communication with a solvent, whereby the cleaning of the capillary flow path ( 12 ) is possible in situ when the solvent in the at least one Kapillarströmungsweg ( 12 ) is introduced. (b) a liquid fuel delivery system in fluid communication with the plurality of fuel injectors ( 10 ); and (c) a controller for controlling the supply of fuel to said plurality of fuel injectors (10). 10 ) to control. Fuel system according to claim 10, wherein the capillary flow path ( 12 ) is formed inside a ceramic body. A fuel system according to claims 10 or 11, wherein the solvent comprises liquid fuel from the source of liquid fuel, and wherein the heat source during cleaning of the capillary flow path (Fig. 12 ) is gradually taken out of service. A method of supplying fuel to an internal combustion engine, comprising the steps of: (a) supplying at least one capillary flow path (FIG. 12 ) a fuel injection device ( 10 ) with liquid fuel, wherein the at least one capillary flow path ( 12 ) has a hydraulic diameter of less than 2 mm; (b) causing a stream of substantially vaporized fuel to pass through an outlet ( 16 ) of the at least one capillary flow path ( 12 ) by passing the liquid fuel in the at least one capillary flow path (FIG. 12 ) is heated; (c) passing the vaporized fuel to a combustion chamber of the internal combustion engine ( 2110 ); and (d) periodically cleaning the at least one capillary flow path (FIG. 12 ) by the at least one capillary flow path ( 12 ) is brought into fluid communication with a solvent, whereby the cleaning of the capillary flow path ( 12 ) is possible in situ when the solvent in the at least one Kapillarströmungsweg ( 12 ) is introduced; wherein the capillary flow path ( 12 ) comprises a channel formed in a monolithic body made of a material selected from the group of ceramics, polymers, metals and composites thereof or a multilayer ceramic body. The method of claim 13, wherein the solvent liquid Fuel includes and heating during the Cleaning step is switched off step by step.