CN102374043B

CN102374043B - Fuel system for multifuel engine

Info

Publication number: CN102374043B
Application number: CN201110221424.7A
Authority: CN
Inventors: G·苏尼拉; J·巴斯玛吉; R·D·帕斯佛
Original assignee: Ford Global Technologies LLC
Current assignee: Ford Global Technologies LLC
Priority date: 2010-08-24
Filing date: 2011-08-03
Publication date: 2016-12-14
Anticipated expiration: 2031-08-03

Abstract

The present invention provides the method and system of the engine fuel system of a kind of fuel including different fuel type for operation.When not requiring fuel is directly sprayed, carry the first fuel type by circulation through high-pressure pump for tuned port injection, thus cooling and/or lubrication high-pressure pump.

Description

Fuel system for multifuel engine

Background technology

Pluralities of fuel system can be used for the desired amount of fuel is delivered to electromotor for burning.A kind of The fuel system of type includes port fuel injection device (the port fuel for each engine cylinder And direct injection injector injector).This port injector can operate during engine start thus Improve carburretion and reduce engine emission.This direct injection injector can be in higher loaded-up condition Period operates thus improves engine performance.It addition, in some conditions can be to port injector Operate with both direct injection injectors, thus balance the advantage of two kinds of fuel conveying.

Direct-injection type fuel system can include the high pressure fuel pump of fuel rail upstream thus promote and pass through direct-injection Formula ejector is delivered to the pressure of the fuel of engine cylinder.But, when high pressure fuel pump cuts out, all As when need not direct fuel injection, the durability of pump can be affected.Specifically, at high pressure While pump does not operate, lubrication and the cooling of pump may be lowered, and thus cause pump to deteriorate.

Research and develop kinds of schemes to reduce deteriorating of high-pressure pump.In a kind of scheme, such as Faix etc. US 6,230, shown in 688, the fuel lubricated stream of constant basis is from the conveying of the low-lift pump being connected to fuel tank Flow branching leaves, and is delivered to high-pressure pump.

But, inventor here has been found that the potential problems using this scheme.Give one example, When fuel tank is emptying or fuel quantity in fuel tank descends below a threshold value, may will no longer be present Constant lubrication flow.Therefore, high-pressure pump may deteriorate.In particular, it is being connected to direct injection system Fuel tank is less than in the bifuel system of the fuel tank being connected to tuned port injection system, and fuel tank may Can be emptying in the more time, cause high-pressure pump to disable continually.So, this can reduce high-pressure pump Reliability.

Summary of the invention

Therefore, in an example, the problems referred to above can be at least partially through operation engine fuel The method of system and process.In one embodiment, the method includes by first kind fuel uniquely Supply to the second petrolift and port fuel injection device from the first fuel tank via the first petrolift Group, the output of the second petrolift connects with direct injection injector group；And by first kind fuel from Two fuel pump outlet supply to port fuel injection device group.

In an example, electromotor can include bifuel system, has storage the first fuel type (all Such as, gasoline) the first fuel tank and storage the second fuel type (ethanol being such as similar to E85 mixes Compound) the second fuel tank.The first group of port injector connected with the cylinder group of electromotor can configure Fuel air mouth to be spurted into described cylinder group.The same second group of direct injection spray connected with described cylinder group Emitter is configurable to inject fuel directly into described cylinder group.The first low-lift pump connected with the first fuel tank It is operable as, along the first fuel channel, the first fuel type is delivered to first group of port injector First share rail.Similarly, the second low-lift pump connected with the second fuel tank is operable as along Second fuel type is delivered to the second of second group of direct injection injector and shares rail by two fuel channels.? In one example, low-pressure fuel pump can use electronic mode to drive.

This fuel system may also comprise high pressure fuel pump, the output of high-pressure pump and first and second groups of injections Device connects, and can arrange along the second fuel channel.In an example, high pressure fuel pump can be adopted Drive by the mode of machinery.This high pressure fuel pump can share rail and second group of direct injection injection via second Device connects, and also can share rail and first group of port injector connection via electromagnetic valve and first.In choosing During fixed engine operation state, such as when requiring that fuel (the first or second fuel type) is carried out When directly spraying, in addition to the low-lift pump corresponding with this fuel type this high-pressure pump the most operable thus Promote and be delivered to the second pressure sharing rail and the fuel through direct injection injector, thus by high pressure Directly the fuel of injection delivers into described cylinder group.

This fuel system may also include the second fuel that the first fuel channel is connected to high-pressure pump upstream First bypass channel of passage, and the first fuel channel is connected to second fuel in high-pressure pump downstream Second bypass channel of passage.This second bypass channel can include electromagnetic valve, the electricity such as electrically controlled Magnet valve, when the valve is opened, is connected to be positioned at second fuel in high-pressure pump downstream by the first fuel channel Passage.Therefore, when open, the output of this high-pressure pump can via electromagnetic valve with first group of air inlet Mouth ejector connection.By comparison, upon closing, this high-pressure pump can be with second group of direct injection injection Device connects.

According to engine operation state, can be to being connected to the first fuel tank and the low pressure of the second fuel tank Pump one or more operation and the operation of high-pressure pump be adjusted, also regulate electromagnetism simultaneously Opening of valve, thus via first and/or second group of ejector offer fuel to cylinder group, simultaneously can be real Sufficiently cool and/or the lubrication of existing high-pressure pump.

Such as, according to engine operation state, and the first fuel tank and the second fuel tank each in The amount of the fuel existed, the first fuel type of the first amount can be entered described cylinder by tuned port injection In.Therefore, the first low-lift pump can be operated to only supply the first fuel to entering via the first petrolift Port injector group.In another example, according to mode of operation, the second fuel type of the second amount can It is injected directly into described cylinder.Therefore, the second low-lift pump can be operated thus to supply the second fuel paramount Press pump, this high-pressure pump may operate to promote the pressure of the second received fuel.The combustion of this higher pressure Then material can supply to second group of direct injection injector from high pressure delivery side of pump.So, straight when realizing When connecing injection, stream or fuel by high-pressure pump realize the sufficiently cool of high-pressure pump and lubrication.

During selected engine operation state, but such as when not requiring direct fuel injection requirement (such as grasp more than a threshold temperature and/or pump due to pump temperature when the cooling of this high-pressure pump and/or lubrication The persistent period made exceedes threshold duration), fuel can spray into described cylinder via high-pressure pump air inlet Group.Specifically, the first low-lift pump can operate the first fuel type uniquely from the first fuel tank Supply is to high-pressure pump, and high-pressure pump can operate via (opening) electromagnetic valve by the first fuel type only One ground supplies to first group of port injector from high pressure delivery side of pump.The output of this high-pressure pump can be assisted Adjust the output of the first low-lift pump thus provide the first of first group of ejector to share the required fuel at rail Rail pressure, and regulate the amount of the fluid circulated by high-pressure pump.Meanwhile, the second low-pressure fuel pump and Two direct injection injectors can be deactivated.Adopt in this way, by via high-pressure pump by the first fuel At least some of type supplies to first group of ejector, though this high-pressure pump when not requiring directly to spray Also can keep lubrication and cooling, thus, reduce high-pressure pump and deteriorate.

In another example, when requiring when directly spraying of the second petrolift, but in the second fuel tank The level of the second fuel less than a threshold value, this first fuel type can supply to directly via high-pressure pump Spray formula ejector group thus also compensate for the second fuel with the high-pressure pump that causes owing to fuel is inadequate of minimizing Deteriorate.Specifically, if the fuel level in the second fuel tank is less than this threshold value, and requirement High-pressure pump cooling and/or lubrication, then the first low-lift pump operable with by the first fuel type uniquely from First fuel tank supply to high-pressure pump, this high-pressure pump operable with uniquely by the first fuel type from height Press pump supplies to direct injection injector group.Here, this electromagnetic valve may remain off.This controller can be true The fixed amount by the first fuel directly sprayed, the amount of this first fuel compensates the will directly sprayed The amount of two fuel and be further used for high-pressure pump cooling and lubrication.Additionally, to obtain at cylinder fuel Now in the case of fluctuation suddenly, such as at cylinder rich oil (cylinder enrichment) period, this electromagnetism Valve can be opened and at least some the first fuel also can be delivered to via electromagnetic valve from high-pressure pump One group of port injector so that the direct injection injection of the first fuel is by the tuned port injection of the first fuel Supplement.Adopt in this way, when the amount deficiency of the second fuel by making the fuel of the first fuel type Flowing is by this high-pressure pump, and lubrication and the cooling of this high-pressure pump are achieved.

Adopt in this way, by circulating at least some fuel when need not directly spray from the first combustion Hopper passes through high-pressure pump, and/or ought not exist and come from (being connected to direct injection injector) second case Fuel time, high-pressure pump can keep lubrication and cooling, thus reduce the deteriorating of high-pressure pump.Additionally,

By reducing due to the second insufficient existence of fuel and/or need not directly spray and disable high pressure The demand of pump, high-pressure pump reliability can be improved.

Accompanying drawing explanation

Fig. 1 schematically describes an exemplary embodiment of the cylinder of internal combustion engine.

Fig. 2 schematically describes the exemplary fuel system of the electromotor that can be used for Fig. 1.

Fig. 3 describes the exemplary embodiment of the fuel system of Fig. 2.

Fig. 4-6 describe according to present disclosure for regulate Fig. 3 fuel delivery system operation from And start the lubrication of high pressure fuel pump and/or the exemplary high level flow diagram of cooling.

Detailed description of the invention

Disclosure relates to operate the method and system of fuel system subsequently, and such as Fig. 2 is System, configures to carry one or more different fuel types to combustion engine, and such as Fig. 1 sends out Motivation.As it is shown on figure 3, this fuel system can include that the first of fuel is selected in configuration with tuned port injection The second ejector group of fuel is selected in ejector group and configuration with direct-injection.High-pressure pump may be provided at the second spray The upstream of emitter group thus promote the pressure of the fuel directly sprayed.So, in the direct fuel injection phase Between, high-pressure pump can be lubricated fully.If there is no q.s fuel for directly spray, And/or be made without directly spraying, then engine controller can be by carrying at least some of air inlet Mouthful injection fuel via high pressure fuel pump keep to port injector high pressure fuel pump lubrication and/ Or cooling.This controller is configurable to perform one or more program, those programs of such as Fig. 4-6, Thus it is selectively opened the electromagnetic valve in high-pressure pump downstream, disable direct-injection system simultaneously, pass through high pressure Allow fuel to while pump be transported to port injector.Adopt in this way, even if by Also pump lubrication and cooling is kept, it is possible to reduce deteriorating of high-pressure pump when not performing directly to spray, and The reliability of pump can be improved.

Fig. 1 describes the combustor of internal combustion engine 10 or the exemplary embodiment of cylinder.Electromotor 10 can be at least Partially by including the control system of controller 12 and coming from vehicle behaviour via input equipment 132 The input of author 130 and be controlled.In this example, input equipment 132 includes gas pedal With the pedal position sensor 134 for producing ratio pedal position signal PP.The cylinder of electromotor 10 (also referred to as " combustor ") 14 can include chamber wall 136, and piston 138 is installed therein. Piston 138 can connecting crank axle 140 so that the reciprocating motion of piston is converted to the rotation fortune of crank axle Dynamic.Crank axle 140 can be connected at least one driving wheel of coach via transmission system.Additionally, Trigger motor (not shown) can be connected to crank axle 140 via flywheel thus enable electromotor 10 Startup operation.

Cylinder 14 can receive air inlet via a series of inlet channel 142,144 and 146.Except Cylinder 14, inlet channel 146 can connect with other cylinders of electromotor 10.In certain embodiments, One or more inlet channels can include such as turbocharger (turbocharger) or supercharger (supercharger) pressurizer.Such as, Fig. 1 illustrates the electromotor being configured with turbocharger 10, including the compressor 174 being arranged between inlet channel 142 and 144 with along exhaust passage 148 The exhaust steam turbine 176 arranged.Compressor 174 can be via axle 180 at least in part by aerofluxus whirlpool Turbine 176 energy supply, wherein, pressurizer is configured to turbocharger.But, in other instances, Such as electromotor 10 is provided with in the example of supercharger, and exhaust steam turbine 176 can optionally be neglected Slightly, wherein, compressor 174 can be by the machinery input energy supply of motor or electromotor.Including throttle plate The air throttle 162 of 164 can be arranged along the inlet channel of electromotor, thus changes offer to electromotor The flow of the air inlet of cylinder and/or pressure.Such as, air throttle 162 can be arranged on compressor 174 times Trip, as it is shown in figure 1, or selectively can be arranged on the upstream of compressor 174.

The aerofluxus of other cylinders coming from electromotor 10 except cylinder 14 can be received in exhaust passage 148. Exhaust sensor 128 is shown connected to the exhaust passage 148 of emission control system 178 upstream.Pass Sensor 128 can select from various suitable sensors, for providing evacuating air/fuel ratio Instruction, such as linear oxygen sensors or UEGO (commonly use or the EGO2 Exhaust Gas Oxygen of wide scope), Double state oxygen sensors or EGO (as described), HEGO (EGO of heating), NOx, HC, or CO sensor, for example.Emission control system 178 can use three-way catalyst (TWC), NOx trap, other emission control systems various, or a combination thereof.

Each cylinder of electromotor 10 can include one or more inlet valve and one or more exhaust valve. Such as, cylinder 14 illustrates at least one the intake poppet valve valve at the upper area including being positioned at cylinder 14 150 and at least one exhaust poppet valves valve 156.In certain embodiments, electromotor 10 is each Cylinder (including cylinder 14) can include being positioned at least two intake poppet valve valve at the upper area of cylinder and At least two exhaust poppet valves valve.

Inlet valve 150 can be controlled by controller 12 via actuator 152.Similarly, exhaust valve 156 Can be controlled by controller 12 via actuator 154.In some conditions, controller 12 can change Signal to actuator 152 and 154 is provided thus control corresponding inlet valve and exhaust valve beat on an off Close.The position of inlet valve 150 and exhaust valve 156 can be by corresponding valve position sensor (not shown) Determine.Valve actuator can use electric air valve actuating type or cam-actuated type, or a combination thereof. Inlet valve and exhaust valve timing can by consistent control, or can use variable air inlet cam timing, Variable exhaust cam timing, double independent variable cam timing or any probability of fixing cam timing. Each cam-actuated system can include one or more cam and available one or more cams wheel Wide switching (CPS), variable cam timing (VCT), VVT (VVT) and/or variable Valve stroke (VVL) system, they can be operated by controller 12 thus change air door operation.Example As, cylinder 14 can selectively include the inlet valve via electric air valve actuation control and via including The exhaust valve of the cam-actuated control of CPS and/or VCT.In other embodiments, inlet valve and row Valve can be by shared air valve actuator or actuating system or VVT actuator or actuating System controls.

Cylinder 14 can use a compression ratio, and this compression ratio is that lower dead center is supreme stops when piston 138 is in The ratio of volume during point.In an example, this compression ratio is in the scope of 9: 1 to 10: 1. But, in some examples using different fuel, this compression ratio can increase.This can occur, Such as, when using higher fuel octane or there is the fuel of higher latent enthalpy of vaporization when.

If owing to it uses directly injection to the effect of combustion knock, then this compression ratio also may be used With

Increase.

In certain embodiments, each cylinder of electromotor 10 can include for starting burning fire flower plug 192.Under selecting operator scheme, ignition system 190 can be in response to the igniting from controller 12 Advance signal SA provides pilot spark via spark plug 192 for combustor 14.But, real at some Executing in example, it is convenient to omit spark plug 192, such as electromotor 10 can pass through automatic ignition or pass through fuel Spray (being exactly this situation for some Diesel engine) and start burning.

In certain embodiments, each cylinder of electromotor 10 may be configured with for providing it fuel One or more fuel injectors.As nonrestrictive example, cylinder 14 includes two combustions as shown Material ejector 166 and 170.Fuel injector 166 and 170 can be configured to conveying from fuel system 8 The fuel received.As understood with reference to Fig. 2-3, fuel system 8 can include one or more fuel tank, Petrolift and fuel rail.Fuel injector 166 be attached directly to cylinder 14 as shown in the figure thus with warp The pulse width of the signal FPW-1 received from controller 12 by electronic driver 168 proportionally will Fuel is directly spurted into wherein.Adopting in this way, fuel injector 166 is straight with what is called by fuel The mode (hereinafter referred to as " DI ") of spray sprays into deflagrating jar 14.Although Fig. 1 illustrates ejector 166 Position the side to cylinder 14, but be selectively disposed at the top of piston, such as close to fire The position of flower plug 192.Owing to the volatility of some fuel based on ethanol is relatively low, so this position The mixing and burning when using fuel handling electromotor based on ethanol can be improved.Selectively, This ejector can be positioned on top and close to inlet valve thus improve mixing.Fuel can be via high compression ignition Material pump and fuel rail are delivered to fuel injector 166 from the fuel tank of fuel system 8.Selectively, Fuel can be carried by single stage fuel pump with low pressure, and in this case, direct fuel sprays Timing if the situation of high-pressure fuel system can be used by more by ratio during compression stroke Limit.Additionally, this fuel tank can have provides the pressure transducer to controller 12 by signal.Combustion One exemplary embodiment of material system 8 will account for reference to Fig. 2.

Fuel injector 170 is arranged in inlet channel 146 rather than as shown in the figure in cylinder 14, It is configured to fuel (hereinafter referred to as " PFI ") in the way of so-called tuned port injection is sprayed into cylinder 14 Air inlet upstream.Fuel injector 170 can spray the fuel received from fuel system 8, with warp The pulse width of the signal FPW-2 received from controller 12 by electronic driver 171 is proportional.Need It is noted that single driver 168 or 171 can be used in two fuel injection systems, or Person can use multiple driver, such as the driver 168 of fuel injector 166 with for fuel The driver 171 of ejector 170, as described.

In alternate example, each of fuel injector 166 and 170 can be configured to direct-injection type fuel spray Emitter, for directly spurting into cylinder 14 by fuel.In another example, fuel injector 166 He 170 each can be configured to port fuel injection device, for spraying fuel to inlet valve 150 Upstream.In other instances, cylinder 14 can only include single fuel injector, and this ejector is configured to Different fuel is received as fuel mixture using different relative quantity from fuel system, and further It is configured to this fuel mixture or directly sprays in described cylinder to spray as direct-injection type fuel Emitter or injection are to the upstream of inlet valve using as port fuel injection device.In this way it will be appreciated that , fuel system described here should not be limited as the special fuel spray described the most by way of example The structure of emitter.

Fuel can be delivered to cylinder by two ejectors during the single loop of cylinder.Such as, each spray Emitter can carry a part for the total fuel injection burning in cylinder 14.Additionally, from each ejector Distribution and/or the relative quantity of the fuel of conveying can be changed along with operating condition, such as start airborne Lotus, pinking and delivery temperature, as described in herein below.The fuel of this tuned port injection can opened Inlet valve event, close inlet valve event (such as, substantially before induction stroke) and beating Carried during both open and close inlet valve operations.Similarly, such as, the fuel of directly injection can With during induction stroke and partly during previous exhaust stroke, during induction stroke and portion Ground is divided to be carried during compression stroke.Such that make for single combustive event, injected combustion Material can also spray from air inlet and direct injection injector with different timings.Additionally, fire for single Burning event, can perform by the multi-injection of conveying fuel in each circulation.Described multi-injection can be in pressure Perform during contracting stroke, induction stroke or its any suitable combination.

As it has been described above, Fig. 1 only illustrates a cylinder of multicylinder engine.

So, each cylinder can be similarly included the air inlet/exhaust valve of itself group, and (respectively) fuel sprays Device, spark plug etc..It should be appreciated that electromotor 10 can include any an appropriate number of cylinder (bag Include 2,3,4,5,6,8,10,12) or more cylinder.Additionally, each of these cylinders includes With reference to cylinder 14 by all parts described by Fig. 1 some or all.

Fuel injector 166 and 170 can have different qualities.These include the difference of size, such as, One ejector can have the spray-hole bigger than other ejectors.Other differences including, but not limited to, Different spray angles, different operation temperature, different directional aim, different injection timings, Different sprinkling characteristics, different positions etc..And, spray according between ejector 170 and 166 Penetrate the distribution ratio of fuel, it is possible to obtain different effects.

Fuel tank in fuel system 8 can keep the fuel of different fuel type, such as has different combustion Material quality and the fuel of different fuel composition.These differences can include different ethanol content, different Water content, different octanes, different heat of vaporization, different fuel mixtures and/or above-mentioned group Close.One example of the fuel with different heat of vaporization can include having relatively low heat of vaporization Gasoline as the first fuel type, there is the ethanol of higher heat of vaporization as the second fuel-based Type.In another example, this electromotor can use gasoline as the first fuel type, comprises fuel and mixes (it is general 85% years old for compound such as E85 (its ethanol of general 85% and the gasoline of 15%) or M85 Methanol and the gasoline of 15%) ethanol as the second fuel type.Other feasible materials comprise water, The mixture of the mixture of methanol, ethanol and water, water and methanol, the mixture etc. of ethanol.

In another example, two kinds of fuel can be the crude alcohol mixture with different alcoholic content, its In, the first fuel type can be the gasoline crude alcohol mixture with relatively low alcohol concentration, such as E10 (it probably has the ethanol of 10%), and the second fuel type can be the gasoline with higher alcohol concentration Alcohol mixture, such as E85 (it probably has the ethanol of 85%).It addition, the first and second fuel Also can be different in other fuel mass, the such as difference of temperature, viscosity, octane number etc..And And, the fuel characteristic of one or two fuel tank may change continually, such as due to fuel tank every day The difference refilled.

Controller 12 is illustrated in figure 1 micro computer, including microprocessor 106, input/output end port 108, for executable program and the electronic storage medium of corrected value, as shown in this particular instance ROM chip 110, random access memory 112, keep stored memory 114 and data Bus.Controller 12 can receive various signals, except those from the sensor being connected to electromotor 10 The signal previously discussed, including the introducing quality air stream coming from mass air flow sensor 122 (MAF) measured value；Come from the starting of temperature sensor 116 being connected to cooling cover 118 Machine coolant temperature (ECT)；Come from be connected to crank axle 140 hall effect sensor 120 (or Person's other types) profile igniting pickoff signals (PIP)；Come from the joint of TPS Valve position (TP)；And come from the absolute Manifold Pressure Signal (MAP) of sensor 124.Send out Motivation rate signal, RPM, can be produced by signal PIP by controller 12.Come from manifold pressure The manifold pressure signal MAP of force transducer can be used for providing the vacuum in inlet manifold or the finger of pressure Show.

Fig. 2 schematically shows the exemplary embodiment 200 of the fuel system 8 of Fig. 1.Now will ginseng The more specifically example of fuel system 200 it is more fully described according to Fig. 3.Fuel system 200 is operable Thus deliver fuel to electromotor 210.As limiting examples, electromotor 210 can refer to send out Motivation 10, before with reference to as described in Fig. 1.

Fuel system 200 can provide fuel to electromotor 210 from one or more different fuels sources. In an example, the first fuel tank 220 and the second fuel tank 230 can be set.Although fuel tank 220 The container of separation for storing fuel it is described as within a context with 230 it should be appreciated that, These fuel tanks are configured to the single-fuel case with the fuel memory area of separation with can substitute for, this A little regions are opened by wall portion or other suitable membrance separation.Further, in certain embodiments, this Film be configurable to by the fuel of selected components between two or more fuel memory areas selective Transmission so that fuel mixture can at least in part by this membrance separation to store at the first fuel Region is formed as the first fuel type and is formed as the second fuel type at the second fuel memory area.

In some instances, the first fuel tank 220 can store the fuel of the first fuel type, and second Fuel tank can store the fuel of the second fuel type, and wherein, the first and second fuel types belong to different Composition.As limiting examples, the second fuel type being included in the second fuel tank 230 can One or more compositions including higher concentration so that the second fuel type has higher than the first fuel Relative pinking rejection ability.

Illustrate, the first fuel and the second fuel is each can include one or more hydrocarbon content, But the second fuel may also comprise the alcoholic content higher than the first fuel concentration.In some conditions, when When carrying with suitable amount relative to the first fuel, this alcoholic content can be that electromotor 210 provides quick-fried Shake suppression, and any suitable ethanol, such as ethanol, methanol etc. can be included.Due to ethanol because The latent heat of vaporization of the increase of ethanol and inflation cooling capacity and can be more all based on hydrocarbon fuel than some As gasoline and diesel oil provide higher pinking suppression, so comprising the fuel energy of higher concentration alcoholic content Enough it is alternatively used for during selected mode of operation providing, for combustion knock, the toleration strengthened.

As another example, ethanol (such as, methanol, ethanol) can have and add water therein to. So, this will reduce the combustibility of alcohol fuel, provides, for storage fuel, the motility increased.Additionally Ground, the heat of vaporization of moisture strengthens the ability that alcohol fuel suppresses as pinking.Additionally, water inclusion energy Enough reduce the overall cost of fuel.

As specific limiting examples, the first fuel type can include gasoline, the second fuel type Ethanol can be included.As another limiting examples, the first fuel type can include gasoline, the second combustion Material type can include the mixture of gasoline and ethanol, and wherein, the second fuel includes than the first fuel concentration High alcohol component (such as E85), so that the second fuel realizes the most quick-fried Shake suppression.In other instances, the first fuel and each of the second fuel include gasoline and ethanol, Thus, the second fuel can include than the first higher alcohol component of fuel concentration.As another example, Second fuel can have ratio the first fuel the most higher octane grade, so that the second fuel ratio One fuel more effectively realizes pinking suppression.It should be appreciated that these examples are appreciated that non- It is restrictive, it is possible to use what other were suitable has the fuel of relatively different pinking rejection characteristic,

Fuel can by one or more fuel injectors from fuel tank 220 and 230 one of them or Multiple it is delivered to electromotor 210.As previously described with respect to fig. 1, electromotor can include one or more Direct injection fuel injector and port fuel injection device.Adopting in this way, fuel can be transported to Electromotor is relative to the diverse location of each engine cylinder.As limiting examples, the first ejector Group 270 can include the one group of port fuel injection device being combined with one group of engine cylinder, the second ejector Group 280 can include the one group of direct injection injector connected with described cylinder group.But, in other instances, First ejector group 270 may refer to the first direct injection fuel injector of each engine cylinder, the second spray Emitter group 280 may refer to the second direct injection fuel injector of each engine cylinder.As another example, First ejector group 270 may refer to the first port fuel injection device of each engine cylinder, the second spray Emitter group 280 may refer to the second port fuel injection device of each engine cylinder.

In some embodiments of fuel system, fuel can provide to the first spray from the first fuel tank 220 Emitter group 270, as shown in 250, thus, it can be delivered to electromotor 210, such as 290 places Show.In certain embodiments, fuel can additionally or alternatively from the first fuel tank 220 provide to Fuel injector group 280, as shown in 252, thus, it can be delivered to electromotor 210, such as 292 Shown in.Adopt in this way, the first fuel can via one or more different fuel injectors from First fuel tank 220 is optionally delivered to each cylinder of electromotor 210.

Additionally, in some embodiments of this fuel system, fuel can provide from the second fuel tank 230 To the second ejector group 280, as shown in 260, thus, it can be delivered to electromotor 210, as Shown in 292.In certain embodiments, fuel can be optionally or additionally from the second fuel Case 230 provides to fuel injector group 270, and as shown in 262, thus, it can be delivered to start Machine 210, as shown in 290.Adopting in this way, fuel can be via one or more different fuels Ejector is optionally delivered to each cylinder of electromotor 210 from the second fuel tank 230.

Additionally, in certain embodiments, fuel is optionally in the first fuel tank 220 and the second combustion Transmit between hopper 230.As an example, it is contained in the first fuel in the first fuel tank 220 Can be transferred to the second fuel tank 230 at least partially, there, its can be contained in the second combustion The second fuel mixing in hopper 230.So, the first fuel and the second fuel primality have In the case of heterogeneity, the first fuel is transferred to the second fuel tank 230 from the first fuel tank 220 can The composition of the second fuel being contained in the second fuel tank 230 is changed with potentiality.

Additionally, in some conditions, the fuel rail being associated with fuel injector can be by will be received in Fuel in fuel rail replaces with different fuel and is optionally rinsed.As an example, this Scheme may be used for the preparation of engine start (such as, being switched off or on) thus is suitable fuel Ejector provide more preferable starting fluid, including the highest volatile fuel, such as gasoline, methane or Be heated fuel.

Forwarding Fig. 3 to, exemplary fuel system 300 is described as to be operated by controller thus performs ginseng According to Fig. 4-6 flow chart describe operation in some or all of.

Fuel delivery system 300 can include the first fuel tank 302 and the second fuel tank 312.Such as Fig. 3 In schematically illustrate, fuel tank 302 and 312 can in terms of their fuel storage capacity the most not With.It is to be understood that in an alternative embodiment, fuel tank 302 and 312 can have phase Same fuel storage capacity.As limiting examples, as discussed, have in the second fuel tank storage In the case of the fuel of higher pinking rejection ability, the second fuel tank can have less than the first fuel tank Fuel storage capacity.Fuel can be supplied to via respective filling fuels passage 304 and 314 To fuel tank 302 and 312.

As limiting examples, the first fuel tank 302 can be configured to store the first fuel type, and Second fuel tank 312 can be configured to storage and has higher concentration knock suppressing component compared to the first fuel The second fuel type.Filling fuels passage 304 and 314 can include fuel identification labelling, is used for knowing Will not be supplied to the type of the fuel of corresponding fuel tank.In an example, the first fuel type bag Include at least some gasoline, and the second fuel type includes at least some ethanol.In another example, One fuel type includes at least some gasoline, and the second fuel type includes the ethanol of at least some type (such as, methanol or ethanol).

The first low-pressure fuel pump 308 connected with the first fuel tank 302 is operable to via the first fuel The fuel of the first kind is supplied to first group of port injector by passage 330 from the first fuel tank 302 342.Adopt in this way, the first fuel channel 330 fluidly the first fuel tank is connected to into Port injector group.In an example, the first petrolift 308 can be the low compression ignition of electronic energy supply Material pump, is at least partially disposed in the first fuel tank 302.The combustion promoted by the first petrolift 308 Material can be relatively low pressure feed enter be connected to first group of port injector 342 (also referred to as First ejector group) (such as, as described herein, four injections of one or more fuel injectors Device) the first fuel rail 340.Although fuel distribution is sprayed by the first fuel rail 340 as shown to first Four fuel injectors of emitter group 342, but it is understood that, the first fuel rail 340 can be by Fuel distribution is to any an appropriate number of fuel injector.As an example, the first fuel rail 340 Can be by a fuel injection of the first ejector group 342 of fuel distribution to each cylinder being used for electromotor Device.It is pointed out that in other instances, the first fuel channel 330 can be by fuel via two Or multiple fuel rail provides the fuel injector to the first ejector group 342.Such as, at engine cylinder In the case of being configured to V-configuration, two fuel rail can be used for distributing fuel from the first fuel channel Fuel injector each to the first ejector group.

The second low-pressure fuel pump 318 being connected with the second fuel tank 312 is operable with by Second Type Fuel supply to the injection of second group of direct injection via the second fuel channel 332 from the second fuel tank 302 Device 352.Adopting in this way, the second fuel tank is fluidly coupled to direct-injection by the second fuel channel 332 Formula ejector group.In an example, the second petrolift 318 can also be electronic energy supply low-pressure fuel Pump, is at least partially disposed in the second fuel tank 312.The fuel promoted by the second petrolift 318 The second fuel channel 332 can be entered by relatively low pressure feed.Second petrolift 318 also can with include Higher pressure fuel pump 328 in the second fuel channel 332 connects.In an example, high pressure Petrolift 328 can use mechanical system energy supply.High pressure fuel pump 328 can be further via the second fuel Rail 350 and connect with direct injection injector group 352, via electromagnetic valve 336 and port injector Group 342 connection.Therefore, the second petrolift 318 low-pressure fuel promoted can be further by high compression ignition Material pump 328 pressurizes thus supplies the higher pressure fuel being used for direct-injection to being connected to second group of ejector One or more fuel injectors of 352 (also referred to as the second ejector groups) (such as, as Described here, four ejectors) the second fuel rail 350.As limiting examples, the second spray One or more fuel injectors of emitter group 352 can be configured to direct injection fuel injector, such as, Before with reference to as described in fuel injector 166.Ejector in the second ejector group 352 is configured to directly In the embodiment of spray formula ejector, the second petrolift 318 and high-pressure pump 328 be operable to into, with by The fuel pressure that first petrolift 308 supplies to the first fuel rail 340 is compared, and is the second fuel rail 350 Higher fuel pressure is provided.As considered here, during selected engine operation state, high Press pump 328 is also operable to be fed through that the first low-lift pump 308 promotes from the first fuel tank 302 The fuel of one fuel type is via direct injection injector group is connected to port fuel injection device group Valve (here, electromagnetic valve) arrives first group of port injector.

Fluid communication between first fuel channel 330 and the second fuel channel 332 can be by first Bypass channel 324 and the second bypass channel 334 realize.Specifically, the first bypass channel 324 can First fuel channel 330 is connected to the second fuel channel 332 of high-pressure pump 328 upstream, meanwhile, First fuel channel 330 can be connected to second combustion in high-pressure pump 328 downstream by the second bypass channel 334 Material passage 332.One or more pressure relief valves may be included in fuel channel and/or bypass channel from And stop or suppress fuel to flow back to enter in fuel storage box.Such as, the first pressure relief valve 326 can It is arranged in the first bypass channel 324 thus reduces or prevent fuel from refluxing from the second fuel channel 332 To the first fuel channel 330 and the first fuel tank 302.Second pressure relief valve 322 may be provided at In two fuel channels 332 thus reduce or prevent fuel to be moved back into the from the first or second fuel stream passage Two fuel tanks 312.

In an example, the first petrolift 308 and the second petrolift 318 can have and be incorporated into pump In pressure relief valve.This integrated pressure relief valve can limit the pressure in corresponding elevator pump fuel circuit Power.Such as, if the pressure relief valve being integrated in the first petrolift 308 can limit electromagnetic valve 336 (intentionally or unintentionally) open and will produce at the first fuel time high-pressure pump 328 pumps Pressure in rail 340.

Electromagnetic valve 336 can be arranged along the second bypass channel 334.In an example, electromagnetic valve 336 Electronic control electromagnetic valve can be used.It addition, electromagnetic valve 336 can include (such as, with electromagnetic valve conllinear ) pressure relief valve.Under selected state, as considered further with reference to Fig. 4-6, electromotor control Device processed can be configured to be selectively opened electromagnetic valve 336 (such as, by being energized solenoid Or power-off, according to the configuration of electromagnetic valve), thus by the amount of the fuel of the first fuel type uniquely from First fuel tank 302 supplies to high-pressure pump 328 via the first petrolift 308, then by the first kind Fuel supplies to port injector group 342 from high-pressure pump.In an example, electromagnetic valve 336 is permitted Permitted fluid along from the direction of fuel channel 332 to fuel channel 330 flow, with limit fluid along from The direction of fuel channel 330 to fuel channel 332.Here, the output of the first petrolift can be adjusted Thus the first fuel rail 340 for port injector group provides fuel pressure, the first fuel type is also Arrange ground and simultaneously supply to entering from fuel under high pressure delivery side of pump and the first low-pressure fuel delivery side of pump Port injector group, comes from least some fuel of the first low-pressure fuel delivery side of pump by bypass height Pressurized fuel pump and be supplied to port injector group.

Selectively, this controller can optionally turn off electromagnetic valve 336, thus allows a certain amount of Fuel is delivered to the first ejector group 342, simultaneously bypass high pressure pump 328 from the first fuel tank 302. Specifically, when requiring directly to spray a certain amount of fuel, this controller can cut out electromagnetic valve 336 And the fuel allowing required amount is delivered to send out via the second ejector group 352 from the second fuel tank 312 Motivation.Meanwhile, a certain amount of fuel, if demand to be had, can from the first fuel tank 302 via First ejector group 342 is delivered to electromotor.By comparison, when not requiring directly to spray, and/ Or when fuel in the second fuel tank 312 level less than a threshold value and require high-pressure pump lubrication and/ Or during cooling, this controller can be opened electromagnetic valve 336 and disable the second ejector group 352 and the Two petrolifts 318, start the first ejector group 342 and the first petrolift 308 thus in conveying simultaneously The fuel making pumping before electromotor is circulated through high-pressure pump.

Electromagnetic valve 336 is also adjustable as so that fuel can provide to fuel rail 340 He from the first fuel tank 350 one of them or the two.Such as, fall in response to the second fuel type in the second fuel tank Below one threshold value, i.e. if fuel quantity is not present in the second fuel storage box for directly injection Foot, then electromagnetic valve 336 can be opened so that a certain amount of first kind fuel can be by the first combustion Material pump 308 and high-pressure pump 328 supply to the second ejector group from the first fuel tank, for directly injection Enter electromotor.It addition, in the case of electromagnetic valve is opened, a certain amount of fuel also can be from the first combustion Material storage box is delivered to the first ejector group, enters electromotor for tuned port injection.

In certain embodiments, electromagnetic valve 336 may also include (such as, with electromagnetic valve conllinear) pressure Relief valve.This pressure relief valve thus can be as back pressure regulator.In such an embodiment, electromagnetic valve 336 The fuel pressure level kept in the first fuel channel 330 and the second fuel channel 332 can be assisted, with And the fuel pressure level that first in fuel rail 340 and the second fuel rail 350.Such as, electromagnetic valve is worked as Opening (intentionally or unintentionally), the pressure of the second fuel rail 350 can be set by this pressure relief valve It is the first pressure (such as, 300psi).So, in the case of not using pressure relief valve, the Pressure in two fuel rail 350 will decrease to the pressure of the second petrolift 318 (it is, elevator pump Pressure), the fuel caused due to vaporization can be produced and release.It addition, low pressure can make fuel atomization dislike Change.Therefore, by including pressure relief valve, this direct injection system (direct injection injector, the second combustion Material rail, etc.) even if also being able to when electromagnetic valve is opened normally work.Additionally, if the second fuel Fuel rail pressure in rail 350 exceedes goal pressure, then pressure relief valve allows pressure to be lowered.

In certain embodiments, the first and/or second bypass channel can also be used in fuel storage box 302 And between 312, transmit fuel.Fuel transmission can be by including one at the first or second bypass channel Or multiple check valve, pressure relief valve, electromagnetic valve and/or pump and promoted.In other embodiments In, fuel storage box one of them can be arranged to height higher than other fuel storage box, thus, combustion Material can be deposited from the fuel that higher fuel storage box is transferred to reduce via one or more bypass channels Storage tank.Adopting in this way, fuel can be transmitted between fuel storage box by gravity, without wanting Ask petrolift to promote that fuel transmits.

The all parts of fuel system 300 can with the engine control system of such as controller 12 even Logical.Such as, except the sensor previously described with reference to Fig. 1, controller 12 can from fuel system Each sensor of 300 associations receives the instruction of mode of operation.Each input can include warp the most respectively The fuel of each fuel storage box 302 and 312 it is stored in by fuel level sensor 306 and 316 The instruction of amount.Except, or alternately in, from exhaust sensor (sensor 126 of such as Fig. 1) The instruction of the propellant composition inferred, controller 12 also can connect from one or more fuel composition sensors Receive the instruction of propellant composition.Such as, the fuel of the fuel being stored in fuel storage box 302 and 312 The instruction of composition can be provided by fuel composition sensor 310 and 320 respectively.It addition, it is or optional Ground, one or more fuel composition sensors can be at fuel storage box fuel injector corresponding with them Arrange along fuel channel in any suitable position between group.Such as, fuel composition sensor 338 May be provided at the first fuel rail 340 or arrange along the first fuel channel 330, and/or propellant composition Sensor 348 may be provided at the second fuel rail 350 or arranges along the second fuel channel 332. As limiting examples, fuel composition sensor can provide for controller 12 and be contained in fuel The instruction of concentration of knock suppressing component or the instruction of octane grade of fuel.Such as, one or Multiple fuel composition sensors can provide the instruction of the alcohol concentration in fuel.

It is pointed out that the relative position of the fuel composition sensor in fuel delivery system can carry For different advantages.Such as, be arranged at fuel rail or along connect fuel injector and one or The sensor 338 and 348 that the fuel channel of multiple fuel storage box is arranged can provide the fuel of gained The instruction of composition, two of which or more kinds of different fuel carried out group before being delivered to electromotor Close.By comparison, sensor 310 and 320 can provide the instruction of the propellant composition at fuel storage box, It likely differs from the composition of the fuel being actually delivered to electromotor.

Controller 12 also is able to control each operation of petrolift 308,318 and 328 thus regulates It is delivered to the amount of the fuel of electromotor, pressure, flow etc..Giving an example, controller 12 can change Become petrolift pressure arrange and/or fuel flow rate thus deliver fuel to the not coordination of fuel system Put.The amount of the first fuel being delivered to the first ejector group via high-pressure pump can be by regulation with coordinate the One low-pressure fuel pump and the output of high pressure fuel pump and be adjusted.Such as, the petrolift of lower pressure It is operable as keeping the specified fuels pressure at fuel injector or fuel rail with the petrolift of elevated pressures Power.The fuel rail pressure sensor being connected to the first common fuel rail can be configured to provide first group of air inlet The estimated value of the fuel pressure existed at mouth ejector.Then, according to calculate rail pressure and required rail pressure it Between difference, can regulate pump output.In an example, use volume displacement combustion at high pressure fuel pump In the case of material pump, the flow control valve of this controller scalable high-pressure pump thus change each pump stroke Effective pump volume.

Turning now to Fig. 4, exemplary process 400 is described, for regulating the pump of Fig. 3, valve and injection Device group thus by the desired amount of fuel provide to electromotor.

At 402, engine operation state can be calculated and/or measure.These power operation shapes State can include such as engine speed, supercharging, driver demanded torque, engine temperature, inflation etc.. At 404, it is stored in the amount of the fuel in the first fuel storage box and is stored in the second fuel storage box In the amount of fuel can be assessed.In an example, the amount being stored in the fuel in each case can With in response to from the fuel level sensor (sensing of such as Fig. 3 being associated with each fuel storage box Device 306 and 316) input that receives and assessed.In an alternative embodiment, each fuel storage box In the amount of fuel (fuel quality sensor, fuel body can be included based on from other proper sensors Long-pending sensor, fuel pressure sensor etc.) input that receives and be pushed off.

At 406, it may be determined that whether the amount of the fuel in the second fuel tank is less than a threshold value.? In one example, this threshold value can correspond to can pass through the second ejector group during power operation The minimum of the fuel of direct-injection.As an example, this fuel level can sense according to fuel level The output of device is determined.Selectively, this controller can infer the second fuel tank according to rail pressure In fuel level (such as, low fuel rail pressure can represent that fuel tank is empty).As another example, This controller can infer the second fuel according to the pump pressure of the second petrolift being connected to the second fuel tank Fuel level (such as, low lifting pump pressure can represent that fuel tank is empty) in case.

So, in the fuel of the q.s for direct-injection is present in the second fuel tank and a certain amount of When fuel is flowed into electromotor via high-pressure pump, guaranteed the lubrication of high-pressure pump by the fuel stream of this pump And cooling.As a comparison, when not having enough fuel, high-pressure pump may be due to the profit reduced Slide and/or cool down and deteriorate more quickly.Accordingly, in response to the fuel in second fuel tank at 406 Level descends below a threshold value, and at 407, the second low-pressure fuel pump being connected with the second fuel tank can To be deactivated, high-pressure pump can be set to minimum volume (such as, least displacement volume) and arrange. Selectively, high-pressure pump can be set to the pump speed of minimum, flow or strokes per minute setting.Additionally, this journey Sequence may proceed to 422, wherein, the appropriate step considered as follows can be used to guarantee the height of fuel system The lubrication of press pump and/or cooling.If the amount of fuel is not less than this threshold value, namely at the second fuel tank The middle fuel that there is q.s, then at 408, will be from each fuel tank via each ejector group The amount of the fuel being delivered to electromotor can be according in the engine operation state calculated and fuel tank Whether there is fuel and be determined.Such as, this may include determining whether via the first ejector group from the first combustion Hopper is delivered to the amount of the first fuel of electromotor and/or via the second ejector group from the second fuel tank It is delivered to the amount of the second fuel of electromotor.The first fuel in an example, in the first fuel tank Can be gasoline, the second fuel in the second fuel tank can be alcohol mixture, such as E85.Cause This, this controller can determine that air inlet sprays into the first amount of the gasoline in described cylinder and/or is injected directly into institute State the second amount of alcohol fuel in engine cylinder.

At 410, it may be determined that the first fuel type is the most defeated via first group of port injector Deliver to electromotor.If it is then at 412, enable the tuned port injection of the first fuel type, First low-lift pump of the first fuel tank can begin to use (thus by fuel sucking-off from first case), First (air inlet) ejector group can begin to use (thus the fuel of pumping is delivered to electromotor). It addition, high-pressure pump can be disabled or disable.In an example, this can include send the signal of telecommunication from And make high-pressure pump stop pumping simultaneously constantly with (such as, the minimal stroke displacement of minimal stroke volume Volume) and/or minimum strokes per minute carry out stroke.In another example, disabling high-pressure pump can include sending electricity Signal thus stop pumping and stroke.Such as, an off-stream unit can be operated to stop pump stroke (example As, by emptying oil-filled lifter).Meanwhile, the second low-pressure fuel pump of the second fuel tank it is connected to Can be deactivated with direct injection injector group.It addition, the electromagnetic valve being connected to the second bypass channel can be closed Close, thus prevent the first fuel type from entering the second fuel channel, high pressure from the first fuel channel flowing Pump can be adjusted to minimum volume (such as, least displacement volume) and arrange, because need not directly spray Penetrate.

From here, this program can advance to 422, wherein it is possible to determine the high-pressure pump of fuel system Cooling and/or lubrication the need of.If it is, as Fig. 5-6 considers, the position of electromagnetic valve Can be adjusted so that the first fuel type energy in the case of there is not direct fuel injection Enough then supplied by high-pressure pump to port injector group by the first low-lift pump.

If determining that the first fuel type carries not via the first ejector group 410, then At 414, it may be determined that whether the first fuel is transported to electromotor, also via the second ejector group It is exactly whether the first fuel will directly be sprayed.In an example, the first fuel type can ring Should drop down onto under a threshold level via in the level of the Second Type fuel in the second fuel tank Two ejector groups carry.This engine controller may determine that must directly spray with compensate by The directly amount of the first fuel type of the amount of the second fuel type of injection.If requiring the first fuel-based Type directly sprays, then at 416, in order to realize the direct injection of the first fuel, the first combustion First low-pressure fuel pump of hopper can be activated (thus from first case sucking-off fuel) second combustion simultaneously Second low-pressure fuel pump of hopper disables, and first (air inlet) ejector group can disable, and second is (straight Spray formula) ejector group is activated (thus pumping fuel is delivered to electromotor).It addition, be connected to The electromagnetic valve of the second bypass channel can cut out thus prevent the first fuel from flowing from the first fuel channel Enter the second fuel tank, and high-pressure pump can start, thus promote the fuel that directly sprayed Pressure.

If determining that the first fuel will carry not via the second ejector group 414, then 418 Place, it may be determined that whether the second fuel is transported to electromotor via the second ejector group, it is, Whether the second fuel will directly be sprayed.If it is then at 420, in order to enable the second fuel Directly injection, the second low-lift pump of the second fuel tank can be activated (thus from second case sucking-off fire Material) simultaneously the first pump of the second fuel tank be deactivated, first (air inlet) ejector group can be stopped With, the second ejector group is activated (thus carrying pumping fuel to electromotor) simultaneously.Additionally, The electromagnetic valve being connected to the second bypass channel can cut out, thus prevents the second fuel from leading to from the second fuel Road flows into the first fuel channel and the first fuel tank.Additionally, this high-pressure pump can be activated thus Promote the pressure of the second fuel directly sprayed.

In some instances, except tuned port injection enters the amount of the first fuel in cylinder, the second fuel Amount can be injected directly in cylinder.In this embodiment, the first pump and the first ejector group Can be enabled extraly thus allow to carry out tuned port injection and directly injection simultaneously.

If the fuel for directly injection is inadequate, it is, the fuel level in the second fuel tank is low In a threshold value (at 406), if and/or the most a certain amount of fuel will be by tuned port injection (412 Place), then at 422, can confirm that cooling and/or the profit of the high-pressure pump the need of fuel system Sliding.If it is then at 424, as Fig. 5-6 considers, the position of electromagnetic valve can be adjusted Save thus before conveying is by first (air inlet) ejector group, realize the first fuel recycle by height Press pump, second (direct injection) ejector group is kept and disables simultaneously.If as a comparison, need not Cooling and/or lubrication, then 426, can pass through suitable by the fuel of appropriate amount from suitable fuel tank When ejector group is transported to electromotor, determined by 412,416 and/or 420.

Turning now to Fig. 5, describe exemplary program 500 and be used to determine whether to need the fuel of Fig. 3 The cooling of the high pressure fuel pump of system and/or lubrication.So, as long as no enabling directly injection or not Directly injection (such as, owing to there is not the direct fuel injection of q.s) may be enabled, Fig. 5's Program can be performed.

At 502, the temperature of high-pressure pump can be calculated and/or measure, such as, by special temperature Degree sensor.At 504, the persistent period of high-pressure pump operation can be determined.For example, it is possible to really Determine when electromotor stopped last time, and when arriving process when pump reactivates lasting from then on Between.In another example, it may be determined that operated many since electromotor unlatching last time has operated this pump For a long time.At 506, it may be determined that whether the temperature of pump is higher than a threshold value.In response to fuel under high pressure The temperature of pump exceedes threshold temperature, at 510, it may be determined that needs pump cooling and/or lubricates, therefore, At 512, can be adjusted so that the first fuel type can be supplied to high pressure fuel pump. If pump temperature is not above this threshold value, then at 508, it may be determined that the pump operated persistent period Whether already more than a threshold value.If it is then this program can be back to 510 thus confirm needs Pump cooling and/or lubrication.Therefore, at 512, as considered in Fig. 6, one or more valves are (all Such as electromagnetic valve), the ejector of pump and petrolift can be conditioned and (such as, beat opening/closing, or open Begin use/disable) thus allow high-pressure pump by by the fuel of the first fuel type via the first low-lift pump And/or the lubrication cooled to high-pressure pump from the first fuel tank supply.

If this pump temperature has not exceeded threshold temperature and/or the pump operated persistent period has not exceeded threshold The value persistent period, then at 514, it may be determined that need not pump cooling and/or lubrication, 516 Place, high-pressure pump can disable or disable.As considered above, this can include that stop pump allowing it simultaneously Continue to carry out stroke with minimum volume (and/or minimum strokes per minute).Selectively, operable one dress is disabled Put thus stop pump, also stop pump stroke simultaneously.Be appreciated that, although given example describe in response to Temperature and the mode of operation of high pressure fuel pump and determine when that the fuel supplying the first fuel type passes through High pressure fuel pump is to port injector group, but in an alternative embodiment, first kind fuel is permissible It is supplied in response at least engine operation state (including engine load or engine speed) High pressure fuel pump.Such as, the first fuel type can pass through the high-pressure pump situation at high engine load Under be supplied to.Additionally, as Fig. 4 considers, the first fuel type may also respond to the second fuel tank In fuel level fall into a below threshold value and supply via the first low-pressure fuel pump and high pressure fuel pump To port injector group.

Turning now to Fig. 6, describe exemplary process 600 thus regulate the electromagnetism of the fuel system of Fig. 3 Valve circulates a certain amount of fuel and passes through high pressure fuel pump, is not specifically enabling the second fuel The when of directly injection.By in response to cooling and/or the requirement of lubrication high pressure fuel pump via the First fuel type is supplied to port injector by one low-pressure fuel pump engine and high pressure fuel pump Group, disabling of high pressure fuel pump can be reduced, and thus reduces deteriorating of pump.So, program 600 can Perform in combination with the program of Fig. 4, specifically, when do not require direct fuel injection (Fig. 4's At 412) and/or fall into below threshold value (at the 406 of Fig. 4) in response to fuel level in the second fuel tank. Additionally, program 600 may be in response to the temperature of high pressure fuel pump more than a threshold temperature and/or in response to Perform in combination with the program of Fig. 5 including the engine operation state of engine load.So, exist Under these states, the second low-lift pump being connected to the second fuel tank and the second ejector group can be deactivated.

At 602, it may be determined that whether require cooling and/or the lubrication of high-pressure pump.As with reference to Fig. 5 Consider, can be after pump have operated one section of threshold duration and/or when pump temperature exceedes threshold value temperature High-pressure pump cooling and/or lubrication is required when spending.So, it is configured to via the second ejector group when electromotor When fuel tank receives fuel, it is, by directly spraying, high-pressure pump may operate to lifting will be by The directly pressure of the fuel of injection.During this operation, will be directly ejected through the combustion of high-pressure pump The passage of material can be sufficiently cool and/or lubricate this pump.But, when not enabling direct-injection (such as, When according to engine operation state require nothing more than fuel carry out tuned port injection time), and/or when not enough Fuel when directly spraying (such as, when the fuel tank level of the fuel with pinking rejection ability During less than a threshold value), high-pressure pump can not be operated or lubricates fully and cool down, acceleration pump Deteriorate.Here, by regulating the electromagnetic valve of fuel system, the fuel of tuned port injection can be by height Press pump is circulated, and is transported to electromotor via the first ejector group afterwards.Or, if be not required to Want tuned port injection, then fuel can only recirculate by pump, until realizing enough coolings And/or lubrication.

It is back to 602, without requiring pump cooling and/or lubrication, then at 603, high-pressure pump Can be deactivated or set and operation is set with minimum volume.By comparison, if require pump cooling and / or lubrication, then 604, it may be determined that whether require tuned port injection.Specifically, can be true Whether fixed first fuel will be transported to electromotor via the first ejector group.If requiring air inlet Spray and require the cooling of high pressure fuel pump, then 606, be positioned at the first low-pressure fuel pump downstream Can open with the electromagnetic valve of the fuel system of high pressure fuel pump upstream, simultaneously the first ejector group and First low-lift pump of one fuel tank is activated.In this state, from the first fuel tank by the first pressure The first fuel that pump promotes directly can be delivered to the along the first fuel channel at least partially One ejector group.Selectively, the most elevated fuel can be transported to via high-pressure pump First ejector group.Specifically, the fuel of the first kind can be uniquely via the first low-pressure fuel Pump is delivered to the first port injector group and high pressure fuel pump from the first fuel tank.Here, though high Pressurized fuel pump connects with direct injection injector group and port injector group, sprays by disabling direct injection Device group and the second low-pressure fuel pump, it is ensured that the first fuel type carries out defeated by high-pressure pump uniquely Send.In an example, the output of the pressure of the first petrolift from the first pressure increase to the second pressure from And allow fuel to stride across electromagnetic valve (such as, Fig. 3 from low-pressure fuel pump (such as, the 308 of Fig. 3) 326) arrive high pressure fuel pump (such as, the 328 of Fig. 3) and stride across electromagnetic valve 336, afterwards Fuel is back to fuel channel 330.

Owing to the second low-lift pump of the second fuel tank is deactivated, so while enable high-pressure pump, but the The pressure of one downstream, pressure relief valve can be less than the pressure of this valve upstream.Therefore, by the first low pressure The first fuel that pump promotes from the first fuel tank at least partially can from the first fuel channel via First bypass channel flows into the second fuel channel.Enter the first fuel of the second fuel channel then Can flow by high-pressure pump, be back to the first fuel along the second bypass channel via electromagnetic valve afterwards Passage.From here, the first fuel can be delivered to electromotor via the first ejector group.Due to second Ejector group is deactivated, so not having the first fuel can be delivered to start via the second ejector group Machine.Meanwhile, the second pressure relief valve in the second fuel channel guarantees that the first fuel does not flow into Two fuel tanks.

The amount of the first fuel being delivered to the first ejector group via high-pressure pump can be by regulation and association The first low-pressure fuel pump and the output of high pressure fuel pump is adjusted to be adjusted.Such as, relatively low-pressure fuel pump Operation with higher pressure petrolift can be conditioned thus provide rule at fuel injector or fuel rail Fixed fuel pressure.The fuel rail pressure sensor being connected to the first common fuel rail can be configured to carry The estimated value of the fuel pressure for existing at first group of port injector.Then, according to calculating rail pressure And the difference between required rail pressure, pump output can be conditioned.In an example, high pressure fuel pump can To be volume displacement petrolift, flow control valve is used to change effective pump volume of each pump stroke.But It is, it should be appreciated that be used as other suitable higher pressure fuel pumps.It is compared to motor The relatively low-pressure fuel pump driven, higher pressure fuel pump can use mechanical system to drive by electromotor Dynamic.The pump piston of higher pressure petrolift can be via cam receiver from engine crankshaft or camshaft Machinery input so that pump operates according to the principle of actuated by cams simplex pump.Adopt in this way, By the fuel coming from low-pressure fuel pump and high pressure fuel pump is supplied to port injector group, can To reduce deteriorating of high-pressure pump.

It is back to 604, if not requiring to carry out tuned port injection, namely, it is not required that via first Whether the first fuel type is delivered to electromotor by ejector group, then at 607, can confirm that and want Directly injection the first fuel type is asked (such as, to reduce in response under the fuel level in the second fuel tank In a threshold value, as Fig. 4 considers).If it is then at 608, this electromagnetic valve can quilt Closing, meanwhile, the first port injector group and the first low-pressure fuel pump are deactivated, and the second direct-injection Formula ejector group enables.The output of the first low-pressure fuel pump and high pressure fuel pump can be conditioned and assist Adjust.Such as, relatively low-pressure fuel pump and higher pressure petrolift can be operated thus be kept fuel injector Or the specified fuels pressure at fuel rail.It is connected to the fuel rail pressure sensor of the second common fuel rail Can configure to provide the estimated value of the fuel pressure existed at second group of direct injection injector.Then, According to the difference calculated between rail pressure and required rail pressure, the output of pump can be regulated.

At 610, it may be determined that whether require further rich oil.In an example, Ke Yigen Further rich oil, such as engine speed load-up condition is required according to the change under engine operation state Change.If requiring rich oil, then at 612, the first ejector group can enable so that by The first fuel type that first low-lift pump promotes from the first fuel tank at least partially can be along One fuel channel is delivered to the first port injector group, at least partially can of the fuel promoted It is delivered to the second direct injection injector group along the second fuel channel via high-pressure pump.First low-lift pump and The output of high-pressure pump can be adjusted so that required fuel pressure can be held in first and second groups Ejector.The feedback coming from each pressure transducer being connected to common fuel rail can be by starting Machine controller uses, thus regulates and coordinate the output of described pump.

Adopting in this way, during the first state, the fuel of the first kind can be uniquely via One low-lift pump is delivered to the first port injector and high-pressure pump from the first fuel tank, and this high-pressure pump is with straight Spray formula ejector connects with port injector.By fuel is being delivered to air inlet via high-pressure pump Disabling this direct injection injector while ejector, fuel can be when cycling through high-pressure pump by air inlet Mouth injection, now need not directly spray, thus keeps cooling and the lubrication of high-pressure pump.By comparison, During not requiring the second situation of cooling and/or lubrication, first kind fuel can be uniquely via the One low-lift pump is delivered to the first port injector from the first fuel tank, by-passes around fuel under high pressure simultaneously Pump.It is additionally, during the third state, all as in response to the decline of fuel level in the second fuel tank, First fuel type can uniquely via the first low-pressure fuel pump and high pressure fuel pump from the first fuel Case is delivered to the second direct injection injector.

By circulating air inlet when not requiring directly to spray and/or when not having fuel directly to spray The fuel of mouth injection, by high pressure fuel pump, can keep high-pressure pump temperature and lubrication, thus reduce pump Deteriorate.Additionally, by reducing the generation that high-pressure pump cuts out, the component life of high-pressure pump can also be prolonged Long.

Skilled person will appreciate that, the program described in Fig. 4-6 can represent any amount of process plan Slightly one or more, such as event-driven, interrupt driving, multitask, multithreading etc..So, Shown various steps or function with shown sequence execution, executed in parallel or can save at some Perform in the case of Lve.Similarly, it is not necessary to need order to be processed with realize purpose described herein, Feature and advantage, but there is provided the order of process to be illustrated and described.Although it is the clearest Illustrate, can be according to the specific policy being currently in use but it will be appreciated by the appropriately skilled person that Be repeatedly carried out shown step or function one or more.

Description leaves it at that.Those skilled in the art will be without departing from this explanation by reading description Multiple changes and improvements are expected in the case of the spirit and scope of book.Such as, with natural gas, gasoline, I3, I4, I5, V6, V8, V10 and V12 electromotor of diesel oil or alternate fuel configuration operation is permissible Use this specification to obtain advantage.

Claims

1. the method operating engine fuel system, including:

By first kind fuel uniquely via the first low-pressure fuel pump from the first fuel tank supply to the Two high pressure fuel pumps and port fuel injection device group, the output of described second high pressure fuel pump and direct-injection Formula ejector group connects；And

Described first kind fuel is supplied to described air inlet from described second fuel under high pressure pump discharge Fuel injector group.

Method the most according to claim 1, wherein said first low-pressure fuel pump is electronic energy supply Low-pressure fuel pump, and wherein said second high pressure fuel pump be machinery energy supply high-pressure pump.

Method the most according to claim 2, wherein, described second high pressure fuel pump is via by institute State direct injection injector group and be connected to the valve of described port fuel injection device group by the described first kind Fuel supply is to described port fuel injection device group.

Method the most according to claim 1, also includes disabling described direct injection injector group and Three petrolifts.

Method the most according to claim 1, wherein, in response to the Equations of The Second Kind in the second fuel tank The level of type fuel drops down onto below threshold level, and it is high that described first kind fuel is supplied to described second Pressurized fuel pump.

Method the most according to claim 1, wherein, in response to described second high pressure fuel pump Temperature exceedes threshold temperature, and described first kind fuel is supplied to described second high pressure fuel pump.

Method the most according to claim 1, wherein, in response to including that engine load is at least One engine operation state, supplies described first kind fuel.

Method the most according to claim 1, wherein, the output quilt of described first low-pressure fuel pump It is adjusted to the first rail to described port injector group and fuel pressure, described first kind fuel are provided Parallel from described second fuel under high pressure delivery side of pump and described first low-pressure fuel delivery side of pump and simultaneously Ground supply, to described port injector group, comes from the fuel of described first low-pressure fuel delivery side of pump At least some be provided to by by-passing around described second high pressure fuel pump described fuel injection Device group.

9. the method operating engine fuel system, including:

During the first state, via the first low-pressure fuel pump by first kind fuel uniquely from first Fuel tank is delivered to the first port injector and the second high pressure fuel pump, described second high pressure fuel pump Outlet the first direct injection injector and described first port injector；

During the second state, via described while by-passing around described second high pressure fuel pump Described first kind fuel is delivered to described by low-pressure fuel pump uniquely from described first fuel tank First port injector；And

During the third state, will via described first low-pressure fuel pump and described second high pressure fuel pump Described first kind fuel is delivered to described first direct injection injection from described first fuel tank uniquely Device.

Method the most according to claim 9, wherein, described first low-pressure fuel pump is relatively low The petrolift of pressure, described second high pressure fuel pump is the petrolift of higher pressure.

11. methods according to claim 10, wherein, described first low-pressure fuel pump uses electricity Flowing mode drives, and described second high pressure fuel pump uses mechanical system to drive.

12. methods according to claim 10, wherein, in described first state and described second During state, described first direct injection injector and the 3rd petrolift are deactivated, wherein, and the described 3rd Petrolift is connected to the second fuel tank.

13. methods according to claim 10, wherein, described first state includes described second The temperature of high pressure fuel pump exceedes one or more of the situation of threshold temperature.

14. methods according to claim 11, wherein, the described third state includes the second fuel Fuel level in case drops down onto below threshold value.

15. methods according to claim 11, wherein, described fuel system include being positioned at along The downstream of described first low-pressure fuel pump of fuel flow directions and the upstream of described second high pressure fuel pump Electromagnetic valve, wherein, during the first state, described electromagnetic valve is opened, wherein, described second During state and the described third state, described closed electromagnetic valve.

16. 1 kinds of fuel system for internal combustion engine, including:

First fuel tank of storage first kind fuel；

Second fuel tank of storage Second Type fuel；

The port fuel injection device group connected with cylinder group；

The direct injection injector group connected with described cylinder group；

The first low-pressure fuel pump connected with described first fuel tank；

The high pressure fuel pump connected with described port fuel injection device group via electromagnetic valve, described high pressure Petrolift connects with described direct injection injector group further；And

Control system, is configured with the instruction for operations described below:

Via described first low-pressure fuel pump and described high pressure fuel pump by first kind fuel only One ground supplies to described port fuel injection device group from described first fuel tank；And

Via described first low-pressure fuel pump and described high pressure fuel pump, the described first kind is fired Material supplies to direct injection injector group from described first fuel tank uniquely.

17. fuel system according to claim 16, wherein, via described first low-pressure fuel Pump and described high pressure fuel pump are by described first kind fuel supply extremely described port fuel injection device Group is in response to cooling or lubricates the requirement of described high pressure fuel pump.

18. fuel system according to claim 16, wherein, via described first low-pressure fuel Pump and the supply of described high pressure fuel pump are in response to described second fuel to described direct injection injector group The fuel level of case drops down onto below threshold value.

19. fuel system according to claim 16, wherein, described first kind fuel includes At least some gasoline, and described Second Type fuel includes at least some ethanol.

20. fuel system according to claim 16, wherein, the first fuel channel fluid ground will Described first fuel tank is connected to described port fuel injection device group, and wherein, the second fuel leads to Conduit fluidly described second fuel tank is connected to described direct injection injector group, and wherein, described High pressure fuel pump connects with port fuel injection device group via electromagnetic valve, and wherein, the second low pressure Petrolift is connected with described second fuel tank and described high pressure fuel pump.