JP5585252B2 - Fuel supply system - Google Patents

Description

  The present invention relates to a fuel supply system that vaporizes high-pressure liquid fuel and supplies the vaporized fuel to energy output means.

  Conventionally, Patent Document 1 discloses a fuel injection valve that injects liquid fuel into an intake port of an engine (internal combustion engine) that is an energy output means, and a heat storage tank that stores high-temperature engine coolant that has risen in temperature while the engine is operating. A fuel supply system is disclosed. In the fuel supply system of Patent Document 1, the fuel injection valve is heated by using the high-temperature cooling water stored in the heat storage tank at the time of starting the engine as a heat source, thereby promoting the vaporization of the fuel injected from the fuel injection valve. The aim is to improve engine startability.

JP 2001-132575 A

  Incidentally, even in a fuel supply system that vaporizes high-pressure liquefied fuel with a vaporizer or the like and supplies the vaporized fuel to an energy output means such as an engine, the fuel supplied to the energy output means at the start of the energy output means By promoting the vaporization, the startability of the energy output means can be improved.

  Furthermore, in this type of fuel supply system, when the high-pressure liquefied fuel is decompressed by the vaporizer, a large temperature drop occurs due to the Joule-Thomson effect. Therefore, as in Patent Document 1, the fuel supplied to the energy output means Is effective for promoting the vaporization of the fuel.

  However, in the fuel supply system disclosed in Patent Document 1, when the engine is started, the fuel injection valve is heated by circulating high-temperature cooling water through a hot water passage formed between the fuel injection valve and the cylinder head of the engine. The fuel cannot be vaporized efficiently. The reason is that since the cylinder head of the engine has a large heat capacity, most of the heat of the high-temperature cooling water is taken away by the cylinder head.

  In view of the above points, it is an object of the present invention to efficiently vaporize a fuel supply system in which high-pressure liquid fuel is vaporized and the vaporized fuel is supplied to an energy output means to promote vaporization. .

In order to achieve the above object, according to the first aspect of the present invention, the liquid fuel storage means (11) for storing the high pressure liquid fuel and the high pressure liquid fuel flowing out from the liquid fuel storage means (11) are depressurized and vaporized. The fuel vaporization means (12) and an energy output that is disposed away from the fuel vaporization means (12) and that consumes the gaseous fuel vaporized by the fuel vaporization means (12) and outputs energy while generating heat. The fuel vaporization means (12) side in order to promote the vaporization of the fuel in the means (EG), the heat storage means (44) for storing heat generated by the heat generated by the energy output means (EG), and the fuel vaporization means (12) A heat supply means (43, 44c) for supplying heat stored in the heat storage means (44), and a heat supply control means for controlling the operation of the heat supply means (43, 44c),
The heat supply control means supplies heat stored in the heat storage means (44) to the fuel vaporization means (12) side when the energy output means (EG) is started, and after the energy output means (EG) is started, It is characterized by a fuel supply system that gradually reduces the heat supplied to the vaporization means (12) side.

  According to this, since the heat supply control means supplies the heat stored in the heat storage means (44) to the fuel vaporization means (12) side when starting the energy output means (EG), the fuel vaporization means (12) The fuel in can be heated to promote vaporization. At this time, since the energy output means (EG) is arranged away from the fuel vaporization means (12), the heat supplied to the fuel vaporization means (12) side is taken away by the energy output means (EG) itself. It is possible to suppress breakage.

  As a result, the fuel vaporization means (12) can efficiently heat the fuel, and the fuel vaporization can be effectively promoted. As a result, the startability of the energy output means (EG) can be effectively improved.

  Furthermore, since the heat supply control means gradually decreases the heat supplied to the fuel vaporization means (12) after the energy output means (EG) is started, the temperature of the fuel vaporization means (12) itself is low, and the fuel It is possible to supply a large amount of heat to the fuel vaporization means (12) immediately after the start of the energy output means (EG) that is most required to promote vaporization of the fuel, and to suppress unnecessary supply of heat after the start.

  As a result, it is not necessary to store unnecessary heat in the heat storage means (44), and the heat storage means (44) can be downsized.

  Note that “supplying the heat stored in the heat storage means (44) to the fuel vaporization means (12) side” in this claim means only supplying heat so as to heat the fuel vaporization means (12) itself. This means that heat is supplied to heat the fuel flowing into the fuel vaporization means (12) or the fuel flowing out from the fuel vaporization means (12). In addition, “energy” in the claims includes mechanical energy, electrical energy, thermal energy, and the like.

According to a second aspect of the present invention, in the fuel supply system according to the first aspect, the heat medium circulating circuit in which the heat medium for cooling the energy output means (EG) is circulated and the heat storage means (44) is disposed. 40) and the heat medium circulation circuit (40), the heat storage circuit that causes the heat medium flowing out from the energy output means (EG) to flow into the heat storage means (44) and the heat medium that flows out from the heat storage means (44) A heat medium circuit switching means (45) for switching to a heat dissipation circuit that flows into the vaporization means (12) side, and a heat medium circuit switching control means for controlling the operation of the heat medium circuit switching means (45),
The heat medium circuit switching control means switches the heat medium circuit (40) to the heat dissipation circuit when starting the energy output means (EG), and switches to the heat storage circuit when storing heat in the heat storage means (44). Features.

  According to this, since the heat medium circuit switching control means can store heat in the heat storage means (44) by switching the heat medium circulation circuit (40) to the heat storage circuit, the energy output means (EG) ) Is switched to the heat dissipation circuit at the time of starting, the heat stored in the heat storage means (44) can be reliably and promptly supplied to the fuel vaporization means (12) side.

According to a third aspect of the present invention, in the fuel supply system according to the second aspect, the heat medium circuit switching control means includes a first reference temperature (1) in which the temperature of the heat medium flowing out from the energy output means (EG) is predetermined. KT1) When the energy output means (EG) is started, the heat medium circulation circuit (40) is switched to a heat dissipation circuit, and the temperature of the heat medium flowing out from the energy output means (EG) is preliminarily set. When the heat storage means (44) stores heat when the temperature is equal to or higher than the set second reference temperature (KT2), the heat medium circulation circuit (40) is switched to the heat storage circuit, and the second reference temperature ( KT2) is set to a temperature higher than the first reference temperature (KT1) .

  According to this, since the heat medium circulation circuit (40) is switched according to the temperature of the heat medium flowing out from the energy output means (EG), the heat generated by the heat generated by the energy output means (EG) is converted into the fuel vaporization means ( When the fuel vaporization promotion in 12) is insufficient, the circuit is switched to a heat radiation circuit, and the heat generated by the heat generated by the energy output means (EG) is sufficient for the fuel vaporization promotion in the fuel vaporization means (12). In this case, switching to the heat storage circuit can be reliably performed.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim is an example which shows a corresponding relationship with the specific means as described in embodiment mentioned later.

It is a whole lineblock diagram of the fuel supply system switched to the circuit for thermal storage of one embodiment. 1 is an overall configuration diagram of a fuel supply system switched to a heat dissipation circuit of an embodiment. It is a time chart which shows the change of the discharge flow rate of an auxiliary cooling water pump at the time of engine starting.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1 and 2 are overall configuration diagrams of the fuel supply system 1 of the present embodiment. The fuel supply system 1 is applied to a vehicle and supplies fuel to an engine (internal combustion engine) EG that outputs driving force for traveling the vehicle. First, the fuel supply system 1 includes a high-pressure tank 11 as liquid fuel storage means for storing high-pressure liquid fuel.

  In the present embodiment, as the fuel stored in the high-pressure tank 11, a fuel that has flammability and is easily liquefied even at room temperature (about 15 ° C. to 25 ° C.) is used for high pressure. That is, the fuel of this embodiment needs to be combustible because it is burned as fuel in the engine EG. Furthermore, it is desirable that the fuel be easily liquefied even at room temperature so that the manufacturing cost can be reduced and the gas can be easily vaporized by reducing the pressure.

  Specifically, in this embodiment, dimethyl ether is employed as a fuel that is flammable, has a latent heat of vaporization of 20% or more of the latent heat of vaporization of water, and is liquefied at 1.5 MPa or less at room temperature. Furthermore, since dimethyl ether is a hydrogen-containing fuel (hydrogen compound), flammable hydrogen gas can be generated by reforming.

  In addition to this, for example, it is a fuel containing hydrogen, and the molecule of the fuel contains at least one atom of S (sulfur), O (oxygen), N (nitrogen), and halogen. A fuel that exhibits hydrogen bonds between molecules may be employed as a fuel having equivalent properties.

  An injection valve 12 a inlet side of the carburetor 12 is connected to the fuel outlet of the high-pressure tank 11. The carburetor 12 constitutes a fuel vaporization means for depressurizing and vaporizing the high-pressure liquefied fuel. Specifically, the vaporizer 12 includes a vaporization container 12b that forms a vaporization space 12c for vaporizing fuel, an injection valve 12a that injects high-pressure liquefied fuel in a mist form in the vaporization space 12c, and the like.

  The injection valve 12a is composed of a nozzle for reducing the fuel pressure by reducing the passage area of the high-pressure liquefied fuel flowing from the branch portion, and an electromagnetic valve for opening and closing the passage for the fuel flowing into the nozzle. And the injection flow volume of the fuel injected from a nozzle is adjusted by adjusting the time which opens this solenoid valve. The operation of the solenoid valve is controlled by a control voltage output from a system control device described later.

  Further, a cooling water passage 41 through which a cooling water (heat medium) circulating through a cooling water circulation circuit 40 described later flows is disposed inside the vaporization space 12 c of the vaporizer 12. The cooling water circulation circuit 40 and the cooling water passage 41 will be described later.

  The flow of the gaseous fuel flowing out from the gaseous fuel outlet of the carburetor 12 is branched into two flows in the fuel pipe 13, and one of the branched gaseous fuels is injected into the combustion chamber of the engine EG. The other gaseous fuel branched into the valve (injector) 15 flows into a reformer (reformer) 16 that reforms the gaseous fuel and generates hydrogen gas.

  The engine EG is composed of a so-called reciprocating engine, and burns and consumes the gaseous fuel supplied from the carburetor 12, and outputs energy that generates mechanical energy as driving force for vehicle travel while generating heat. Means. Further, as described above, the engine EG is connected to the carburetor 12 via the fuel pipe 13. Therefore, the engine EG of the present embodiment is arranged away from the carburetor 12 without contacting the carburetor 12.

  The injector 15 is fixed to the cylinder head of the engine EG and injects gaseous fuel toward the intake port of the engine EG. Thus, an air-fuel mixture in which gaseous fuel and combustion air (intake air) are mixed is supplied into the combustion chamber. More specifically, the injector 15 is configured by an electromagnetic valve that opens and closes a fuel supply passage that supplies fuel into the intake passage.

  Further, the operation of the solenoid valve is controlled by a control voltage output from the system control device. Accordingly, the injector 15 can adjust the supply flow rate of the fuel supplied into the combustion chamber by adjusting the opening time of the electromagnetic valve, similarly to the injection valve 12a of the carburetor 12.

  In FIG. 1, for clarity of illustration, only one cylinder of the engine EG is schematically shown. However, this engine EG is a multi-cylinder type (for example, four cylinders) engine, and is an injector. 15 is provided for each cylinder.

  The reformer 16 generates hydrogen gas by heating a gaseous fuel to a reformable temperature under a catalyst to cause a reforming reaction. Specifically, in the present embodiment, dimethyl ether, which is a hydrocarbon-based fuel, is employed as the fuel. Therefore, the fuel is heated to 250 ° C. or higher and subjected to a steam reforming reaction under the catalyst to generate hydrogen. Generate gas. Hydrogen gas generated in the reformer 16 is mixed with intake air as auxiliary fuel and supplied to the combustion chamber from the intake port of the engine EG.

  Next, the cooling water circulation circuit 40 will be described. The cooling water circulation circuit 40 is a heat medium circulation circuit that circulates cooling water (for example, ethylene glycol aqueous solution) that cools the engine EG. The cooling water circulation circuit 40 is disposed in the vaporization space 12c of the vaporizer 12, and the engine EG The engine cooling passage 42, the cooling water pump 43, the heat storage tank 44 for storing the cooling water flowing out from the engine EG, and the like are connected by cooling water piping.

  The cooling water passage 41 is constituted by a meandering cooling water pipe, and is arranged in the vaporization space 12c so that the fuel injected from the injection valve 12a is blown. For this reason, the fuel sprayed is heated by the high temperature cooling water which distribute | circulates the cooling water path 41, and vaporization is accelerated | stimulated. In other words, the amount of heat for the vaporization latent heat of the fuel is absorbed from the high-temperature cooling water flowing through the cooling water passage 41 to cool the cooling water.

  The cooling water pump 43 is an electric water pump that pumps cooling water to an engine cooling passage 42 formed in the engine EG, and the rotation speed (flow rate) is controlled by a control signal output from the system control device. The

  The heat storage tank 44 has an inner tank portion and an outer tank portion made of a material excellent in corrosion resistance (stainless steel in this embodiment), and a heat insulating layer is maintained by maintaining a substantially vacuum between the inner tank portion and the outer tank portion. And a heat storage means for storing heat generated by the engine EG.

  The heat storage tank 44 is formed with an inflow port 44a through which cooling water flows in and an outflow port 44b through which cooling water flows out. Auxiliary cooling water that sucks up and pumps the cooling water in the heat storage tank 44 to the outflow port 44b. A pump 44c is connected. The auxiliary cooling water pump 44c is an electric water pump having the same configuration as the cooling water pump 43, and the rotation speed (flow rate) is controlled by a control signal output from the system control device.

  As this auxiliary cooling water pump 44c, a cooling pump having a cooling water pumping capability lower than that of the cooling water pump 43 is adopted. Therefore, the auxiliary cooling water pump 44c may be integrated as a configuration in which the heat storage tank 44 is built.

  The cooling water circulation circuit 40 is connected to an electric circuit switching valve 45 as a heat medium circuit switching means for switching the circuit configuration. The circuit switching valve 45 is an electric rotary valve whose operation is controlled by a control signal output from the system control device.

  Specifically, as shown in FIGS. 1 and 2, the circuit switching valve 45 is connected to the outlet side of the engine cooling passage 42, the inflow port 44 a side of the heat storage tank 44, and the engine cooling passage 42 via cooling water piping. A circuit that simultaneously connects the outlet side and the inlet side of the cooling water passage 41 and a circuit that directly connects the outlet side of the engine cooling passage 42 and the inlet side of the cooling water pump 43 are switched.

  Further, as a cooling water pipe, a pipe connecting the outlet side of the cooling water passage 41 and the suction port side of the cooling water pump 43, and a discharge port side of the cooling water pump 43 and an inlet side of the engine cooling passage 42 are connected. A cooling water pipe or the like is provided.

  Therefore, the circuit switching valve 45 is switched to a circuit that simultaneously connects the outlet side of the engine cooling passage 42 and the inlet port 44a side of the heat storage tank 44 and the outlet side of the engine cooling passage 42 and the inlet side of the cooling water passage 41. When the cooling water pump 43 is operated in this state, the cooling water is supplied from the cooling water pump 43 → the engine cooling passage 42 → the circuit switching valve 45 → the cooling water passage 41 → the cooling water as shown by the broken line arrow in FIG. A part of the high-temperature cooling water that circulates in the order of the pump 43 and flows out of the engine cooling passage 42 flows into the heat storage tank 44 through the circuit switching valve 45.

  In other words, the high-temperature cooling water that has flowed out of the engine EG (specifically, the engine cooling passage 42) flows into the heat storage tank 44, thereby switching to a circuit that stores the heat generated by the engine EG in the heat storage tank 44. . In the following description, the cooling water circulation circuit 40 thus switched is described as a heat storage circuit.

  When the cooling water circulation circuit 40 is switched to the heat storage circuit, the cooling water flowing through the cooling water passage 41 is cooled by the latent heat of vaporization of the fuel as described above, and the cooled cooling water is passed through the engine cooling passage 42. The engine EG is cooled by passing through.

  In addition, when the cooling water pump 43 is operated in a state where the circuit switching valve 45 is switched to a circuit that connects the outlet side of the engine cooling passage 42 and the suction port side of the cooling water pump 43, the cooling water is As indicated by the broken line arrow 2, the coolant circulates in the order of the coolant pump 43 → the engine cooling passage 42 → the circuit switching valve 45 → the coolant pump 43, and is sucked up from the heat storage tank 44 by the suction negative pressure of the coolant pump 43. High-temperature cooling water flows into the cooling water passage 41.

  That is, the heat stored in the heat storage tank 44 is supplied to the vaporizer 12 by flowing the high-temperature cooling water flowing out from the outflow port 44 b of the heat storage tank 44 into the cooling water passage 41 side disposed in the vaporizer 12. The circuit is switched to. In the following description, the cooling water circulation circuit 40 thus switched is described as a heat dissipation circuit.

  In the present embodiment, when the cooling water circulation circuit 40 is switched to the heat dissipation circuit, the auxiliary cooling water pump 44c is operated in addition to the cooling water pump 43. Thereby, the high-temperature cooling water is reliably introduced from the heat storage tank 44 to the cooling water passage 41 side. Therefore, the cooling water pump 43 and the auxiliary cooling water pump 44 c of the present embodiment constitute a heat supply means for supplying the heat stored in the heat storage tank 44 to the vaporizer 12.

  Next, the electric control unit of this embodiment will be described. The system control device outputs a control signal or control voltage to a well-known microcomputer including a CPU that performs control processing and arithmetic processing, and a storage circuit such as a ROM and RAM that store programs, data, and the like. The circuit includes an input circuit to which detection signals from various sensors are input, a power supply circuit, and the like.

  The various control target devices 12a, 15, 43, and 44c described above are connected to the output side of the system control device, and the system control device controls the operation of these control target devices. Connected to the input side of the system control device is a sensor group for engine control that detects physical quantities used to control the operation of the engine EG.

  Specifically, the sensor group for engine control includes an accelerator opening sensor that detects the accelerator opening, a rotation speed sensor that detects the rotation speed of the engine EG, a fuel pressure sensor that detects the fuel pressure flowing into the injector 15, A throttle position sensor that is disposed in the intake path of the engine EG and detects the valve opening of a throttle valve that adjusts the intake flow rate, and detects the temperature of cooling water that flows out of the engine EG (specifically, the engine cooling passage 42). A cooling water temperature sensor (none of which is shown) is provided.

  Further, an operation signal of a switch group such as a start switch for starting or stopping the vehicle and an ignition switch for starting the engine EG is input to the input side of the system control device.

  Further, the system control device is configured such that the above-described control means for controlling the various devices to be controlled is integrally configured, but the configuration (hardware and software) for controlling the operation of each device to be controlled among the system control devices. Constitutes the control means of each control target device. For example, the configuration for controlling the operation of the cooling water pump 43 and the auxiliary cooling water pump 44c constitutes a heat supply control means, and the configuration for controlling the operation of the circuit switching valve 45 constitutes a heat medium circuit switching control means.

  Next, the operation of the fuel supply system 1 of the present embodiment having the above configuration will be described. First, when the ignition switch is turned on and the engine EG is started, the system control device executes the engine control program stored in the storage circuit. In this engine control program, the operation of various devices to be controlled is controlled according to the operating state of the engine.

  When the engine control program is executed, the system control device operates the cooling water pump 43 so that the reference rotation speed (reference cooling water pumping ability) stored in advance in the storage circuit is reached. Further, the system control device reads various detection values of the sensor group for engine control every predetermined control cycle, and controls the circuit switching valve 45, the injection valve 12a, the injector 15 and the like based on the read detection values. Determine the operating state of the equipment.

  First, the circuit switching valve 45 is determined so that the cooling water circulation circuit 40 becomes a heat dissipation circuit when the engine EG is started. Further, when the cooling water circulation circuit 40 is switched to the heat radiation circuit, the auxiliary cooling water pump 44c is put into an operating state. Thereby, the high-temperature cooling water in the heat storage tank 44 flows into the cooling water passage 41. That is, the heat stored in the heat storage tank 44 is supplied to the vaporizer 12 side.

  In the present embodiment, specifically, when the temperature of the cooling water detected by the cooling water temperature sensor is equal to or lower than a predetermined first reference temperature KT1 (80 ° C. in the present embodiment), the engine EG It is time to start.

  Further, with respect to the auxiliary cooling water pump 44c, as shown in the time chart of FIG. 3, a predetermined time (30 seconds in the present embodiment) elapses after the cooling water circulation circuit 40 is switched to the heat dissipation circuit. Until this is done, the cooling water pumping capacity (discharge flow rate) is controlled to be substantially maximum, and thereafter, the cooling water pumping capacity is controlled to gradually decrease. That is, the heat supplied to the carburetor 12 side is controlled so as to gradually decrease after the engine EG is started.

  In FIG. 3, the discharge flow rate of the auxiliary cooling water pump 44c is indicated by a thick solid line, and the integrated value (unit: J) of the heat supplied to the vaporizer 12 side according to the change in the discharge flow rate of the auxiliary cooling water pump 44c. ) Is indicated by a thick broken line.

  Thereafter, when the temperature of the cooling water detected by the cooling water temperature sensor becomes equal to or higher than a predetermined second reference temperature KT2 (90 ° C. in the present embodiment), it is not at the time of starting the engine EG, and heat storage As it becomes possible to store heat in the tank 44, the cooling water circulation circuit 40 is determined to be a heat storage circuit, and the auxiliary cooling water pump 44c is stopped. Thereby, the high-temperature cooling water that has flowed out of the engine EG flows into the heat storage tank 44. That is, heat generated by the engine EG is stored in the heat storage tank 44.

  Next, for the injector 15, the system control device stores in advance in the storage circuit based on the engine speed, the accelerator opening signal, the valve opening of the throttle valve, and the like read at every predetermined control cycle. With reference to the control map, a target supply flow rate required to output the required output requested by the engine EG is determined.

  Further, based on the determined target supply flow rate, engine speed, fuel pressure at the inlet side of the injector 15, etc., a supply flow rate supplied from the injector 15 to the combustion chamber with reference to a control map stored in advance in the storage circuit Determines the valve opening time of the injector 15 which becomes the target supply flow rate.

  Here, the fuel supplied to the engine EG is the fuel vaporized by the carburetor 12. Further, in the present embodiment, the fuel vaporized by the carburetor 12 is supplied not only to the engine EG but also to the reformer 16. Therefore, the vaporization flow rate (mass flow rate) of the fuel vaporized by the carburetor 12 needs to be larger than the supply flow rate (mass flow rate) of the fuel supplied from the injector 15 to the combustion chamber.

  Therefore, the system control device refers to the control map stored in advance in the storage circuit based on the target supply flow rate, the fuel pressure on the inlet side of the injection valve 12a, and the like, similarly to the valve opening time of the injector 15 described above. Thus, the valve opening time of the injection valve 12a is determined so that the vaporization flow rate of the fuel vaporized by the carburetor 12, that is, the injection flow rate of the fuel injected from the injection valve 12a is larger than the target supply flow rate by a predetermined amount.

  Then, the system control device outputs a control voltage to the injector 15 and the injection valve 12a through the output circuit or the drive circuit (EDU) so as to supply the fuel only during the determined valve opening time.

  After that, until the stop of the vehicle is requested by the start switch, reading of the detection signal and the operation signal described above at every predetermined control cycle → determination of the valve opening time of the injector 15 and the injection valve 12a → the determined valve opening The control routine such as the output of the control voltage that becomes time is repeated. Thereby, the engine EG can be operated while generating the required drive torque.

  Further, the system control apparatus of the present embodiment energizes an electric heater (not shown) as a reforming heating means provided in the reformer 16 with the start of the engine EG, and the reformable temperature. The fuel is heated until the above is reached. Thereby, hydrogen gas can be supplied to the combustion chamber of the engine EG as auxiliary fuel.

  Since the fuel supply system 1 of this embodiment operates as described above, the following excellent effects can be obtained.

  In the fuel supply system 1 of the present embodiment, when the engine EG is started, the cooling water circulation circuit 40 is switched to the heat dissipation circuit and the high-temperature cooling water stored in the heat storage tank 44 flows into the cooling water passage 41. The heat stored in 44 can be reliably and promptly supplied to the vaporizer 12 side. Therefore, when the engine EG is started, the fuel in the carburetor 12 can be reliably and promptly heated to promote vaporization.

  At this time, since the engine EG is disposed away from the carburetor 12, it is possible to suppress the heat supplied to the carburetor 12 from being taken away by the engine EG itself. As a result, the fuel can be efficiently heated in the vaporizer 12, and the vaporization of the fuel can be effectively promoted. As a result, the startability of the engine EG can be effectively improved.

  Furthermore, since the cooling water pumping capacity of the auxiliary cooling water pump 44c is gradually reduced after a predetermined time has elapsed after the engine EG is started, the heat supplied to the vaporizer 12 can be gradually reduced.

  Therefore, when the temperature of the carburetor 12 itself is low, such as after the engine EG is started, and fuel vaporization is most required to be promoted, a large amount of heat is supplied to the carburetor 12, and after the start, Necessary heat supply can be suppressed. As a result, it is not necessary to store an unnecessary amount of cooling water in the heat storage tank 44, and the heat storage tank 44 can be downsized.

  Furthermore, according to the fuel supply system 1 of the present embodiment, the circuit configuration of the cooling water circulation circuit 40 is switched according to the temperature of the cooling water flowing out from the engine EG (specifically, the engine cooling passage 42). When the heat generated by the heat generation of the engine EG is insufficient for promoting the fuel vaporization in the carburetor 12, the heat is generated by switching to the heat dissipation circuit, and the heat generated by the heat generation of the engine EG is sufficient for promoting the fuel vaporization in the carburetor 12. In this case, the control for switching to the heat storage circuit can be surely executed.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and can be variously modified as follows without departing from the spirit of the present invention.

  (1) In the above-described embodiment, the vaporizer 12 that injects liquid fuel into the vaporization space 12c in the form of a mist is employed as the fuel vaporization unit. However, the fuel vaporization unit is not limited to this. For example, a heat exchanger that exchanges heat between the high-pressure liquefied fuel and the heat medium may be employed. In this case, it is not necessary to inject the high-pressure liquefied fuel in the form of a mist, and the flow rate of the high-pressure liquefied fuel flowing into the heat exchanger may be adjusted.

  (2) In the above-described embodiment, the example in which the engine (internal combustion engine) EG is employed as the energy output means has been described. However, the energy output means is not limited to this. For example, a fuel cell that outputs an electric energy by causing an electrochemical reaction between a fuel gas (hydrogen gas) and an oxidant gas (air) may be employed.

  (3) In the above-described embodiment, the example in which the heat supply unit is configured by the cooling water pump 43 and the auxiliary cooling water pump 44c has been described. However, the heat supply unit is not limited thereto.

  For example, the auxiliary cooling water pump 44c may be eliminated, and the heat supply means may be configured by only the cooling water pump 43. In addition, a variable throttle mechanism that generates a passage resistance of the cooling water flowing out from the outlet port 44b of the heat storage tank 44 is adopted, and the cooling that flows into the cooling water passage 41 by changing the throttle opening of the variable throttle mechanism. The water flow rate may be changed.

  (4) In the above-described embodiment, the example in which the heat medium circuit switching unit is configured by the circuit switching valve 45 has been described, but the heat medium circuit switching unit is not limited to this. For example, a plurality of on-off valves that open and close each cooling water passage may be employed, and the heat medium circulation circuit may be switched by changing the on-off state of these on-off valves. Of course, the heat medium circuit switching means may be configured by combining three-way valves and four-way valves.

  (5) In the above-described embodiment, when the heat stored in the heat storage tank 44 is supplied to the carburetor 12, the mist-like fuel injected from the injection valve 12a, that is, the fuel flowing out from the carburetor 12 is supplied. Although the example which did was demonstrated, the means to supply the heat | fever stored in the thermal storage tank 44 to the vaporizer | carburetor 12 side is not limited to this.

  For example, the cooling water passage 41 may be formed in a spiral shape and wound around the outer periphery of the injection valve 12a. Thereby, the heat stored in the heat storage tank 44 can be supplied to the injection valve 12a itself, and the fuel flowing into the vaporizer 12 (injection valve 12a) can be heated to promote vaporization. Moreover, you may arrange | position so that it may wrap around the outer periphery of the fuel channel which flows in into the injection valve 12a. Thereby, vaporization can be accelerated by heating the fuel flowing into the vaporizer 12.

  (6) In the above-described embodiment, the example in which the heat storage tank 44 that stores the high-temperature cooling water flowing out from the engine EG that is the energy output means is employed as the heat storage means, but the heat storage means is not limited thereto. For example, a heat storage means that stores heat chemically may be employed.

  Specifically, a chemical substance that generates heat by chemically reacting with the fuel is contained in a sealed container, and when the engine EG is started, reaction heat between the fuel and the chemical substance is supplied to the vaporizer 12 to start the engine EG. When the time is up, the chemical substance may be regenerated from the compound of the fuel and the chemical substance by the heat of the engine EG. That is, the heat of the engine EG may be stored by regenerating the chemical substance when the engine EG is not started.

  (7) In the above-described embodiment, the example in which the fuel supply system of the present invention is applied to a vehicle has been described. However, the application of the present invention is not limited to this. For example, you may apply to the boiler apparatus etc. which burn a fuel and output thermal energy.

  (8) In the above-described embodiment, an example in which the reformer 16 is used to supply hydrogen gas as auxiliary fuel to the engine EG has been described. However, the reformer 16 uses the vaporizer 12 to supply fuel. Since it is not an essential configuration for obtaining the effect of efficiently heating and promoting vaporization, it may be eliminated.

11 High Pressure Tank 12 Vaporizer 43 Cooling Water Pump 44 Heat Storage Tank 44c Auxiliary Cooling Water Pump 45 Circuit Switch Valve

Claims (3)

Liquid fuel storage means (11) for storing high pressure liquid fuel;
Fuel vaporization means (12) for depressurizing and vaporizing the high-pressure liquid fuel flowing out from the liquid fuel storage means (11);
An energy output means (EG) that is spaced apart from the fuel vaporization means (12), consumes the gaseous fuel vaporized by the fuel vaporization means (12), and outputs energy while generating heat;
Heat storage means (44) for storing heat generated by heat generation of the energy output means (EG);
Heat supply means (43, 44c) for supplying heat stored in the heat storage means (44) to the fuel vaporization means (12) side in order to promote fuel vaporization in the fuel vaporization means (12);
Heat supply control means for controlling the operation of the heat supply means (43, 44c),
The heat supply control means supplies heat stored in the heat storage means (44) to the fuel vaporization means (12) when the energy output means (EG) is started, and the energy output means (EG). The fuel supply system is characterized by gradually decreasing the heat supplied to the fuel vaporization means (12) side after starting the engine. A heat medium circulating circuit (40) in which the heat medium for cooling the energy output means (EG) is circulated and the heat storage means (44) is disposed;
The heat medium circulation circuit (40) allows the heat medium flowing out from the energy output means (EG) to flow into the heat storage means (44) side and the heat medium flowing out from the heat storage means (44) to the heat storage circuit (40). A heat medium circuit switching means (45) for switching to a heat dissipation circuit that flows into the fuel vaporization means (12) side;
A heat medium circuit switching control means for controlling the operation of the heat medium circuit switching means (45);
When the energy output means (EG) is started, the heat medium circuit switching control means switches the heat medium circuit (40) to the heat dissipation circuit and stores heat in the heat storage means (44). The fuel supply system according to claim 1, wherein the fuel supply system is switched to an operation circuit. The heat medium circuit switching control means starts the energy output means (EG) when the temperature of the heat medium flowing out from the energy output means (EG) is equal to or lower than a predetermined first reference temperature (KT1). Sometimes, the heat medium circulation circuit (40) is switched to the heat dissipation circuit, and the temperature of the heat medium flowing out from the energy output means (EG) is equal to or higher than a predetermined second reference temperature (KT2). When the heat is stored in the heat storage means (44), the heat medium circulation circuit (40) is switched to the heat storage circuit,
The fuel supply system according to claim 2, wherein the second reference temperature (KT2) is set to a temperature higher than the first reference temperature (KT1) .

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