JP2008274825A - Starting device for flexible fuel vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a starting device for a flexible fuel vehicle, reducing burden on a battery by preventing excessive heating of alcohol fuel in low-temperature start of an engine to extend battery life, and maintaining good fuel economy. <P>SOLUTION: In the starting device for a flexible fuel vehicle heating the alcohol fuel in the low-temperature start of the engine 1 to improve the startability of the engine 1, a degree of heating of the alcohol fuel in a delivery pipe 26 by a heater 27 in the low-temperature start of the engine 1, based on a cooling water temperature detected by a cooling water temperature sensor 32 and a standing time from previous stop of the engine 1 to the engine restart measured by a sleep timer 34. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a starter for a flexible fuel vehicle in which fuel is heated to start the engine at a low temperature start of the engine, and more particularly to a measure for optimally heating the fuel.

Conventionally, in a flexible fuel vehicle in which an engine is driven by alcohol fuel as fuel, the alcohol fuel is heated by a heater in accordance with the temperature of the cooling water when the engine is started at a low temperature. There is known one that improves the startability of the engine by starting the engine (see, for example, Patent Document 1).
JP-A-5-149223

  However, in the above-mentioned conventional one, the temperature of the cooling water is applied as a parameter for heating the fuel such as alcohol fuel at the time of starting the engine at a low temperature, so that the fuel may be heated excessively by a heater or the like. .

  This is because the temperature of the cooling water reaches a lower limit temperature at which a predetermined time (for example, about 12 hours) has passed since the previous engine was stopped, but it does not decrease any more. This is because residual heat remains inside the cylinder block (for example, a piston or the like) of the engine even if the temperature of the cooling water becomes the lower limit temperature after a lapse of time. This residual heat inside the cylinder block remains even after 24 hours or more have passed since the last time the engine was stopped, even when the vehicle is left at a relatively high altitude.

  Therefore, in the case where the fuel is heated using only the temperature of the cooling water as a parameter at the time of cold start of the engine, the temperature inside the cylinder block is kept at the low temperature start of the engine that has been left for about 12 hours when the temperature of the cooling water becomes the lower limit temperature. The fuel will be heated to the maximum while ignoring the residual heat. As a result, the fuel is excessively heated despite the presence of residual heat inside the cylinder block. This excessive heating of the fuel increases the burden on the battery and adversely affects the battery life. In addition, since the total current value of the battery that has been consumed due to excessive heating of the fuel must be replenished while the vehicle is running, the fuel consumption deteriorates.

  The present invention has been made in view of the above points, and the object of the present invention is to reduce the burden on the battery by eliminating excessive heating of the fuel when the engine is started at a low temperature, thereby extending the life of the battery. Another object of the present invention is to provide a flexible fuel vehicle starter capable of maintaining good fuel efficiency.

  In order to achieve the above object, the present invention is premised on a starting device for a flexible fuel vehicle in which fuel is heated at the time of starting the engine at a low temperature to improve the starting performance of the engine. And it is provided with the leaving time measurement means which measures the leaving time until it restarts after stopping an engine last time, the cooling water temperature detection means which detects the temperature of a cooling water, and the heating means which heats a fuel. Further, a heating degree that determines the degree of heating of the fuel by the heating means at a low temperature start of the engine based on the temperature of the cooling water detected by the cooling water temperature detecting means and the standing time measured by the standing time measuring means A determination means is provided.

  More specifically, the heating means is provided with a heat quantity selecting means for selecting a heat quantity for heating the fuel, and the heating degree of the fuel by the heating degree determining means is selected by the heat quantity selecting means.

  Further, the heating means is provided with a time selection means for selecting a time for heating the fuel, and the heating degree of the fuel by the heating degree determination means is selected by the time selection means.

  Due to this specific matter, the degree of heating at which the fuel is heated when the engine is started at a low temperature is determined based on the temperature of the cooling water and the standing time until the engine is restarted after the previous stop of the engine. The selection means is appropriately selected and determined. For this reason, the cylinder block at the time of low temperature start of the engine that has been left for about 12 hours when the temperature of the cooling water becomes the lower limit temperature, like the case where the fuel is heated using only the temperature of the cooling water as a parameter at the time of low temperature start of the engine The fuel is not heated excessively ignoring the internal residual heat. This eliminates excessive heating of the fuel when the engine is started at a low temperature, thereby reducing the load on the battery and extending the life of the battery. In addition, the consumption of the battery due to excessive heating of the fuel is suppressed, and the burden of replenishing the total current value consumed by the battery while the vehicle is running is reduced, so that the fuel consumption can be kept good.

  In short, the residual heat inside the cylinder block is determined by determining the degree of fuel heating at the time of engine cold start based on the temperature of the cooling water and the standing time until the engine is restarted after the previous stop. Therefore, it is possible to prevent excessive heating of the fuel while ignoring the fuel consumption, thereby reducing the burden on the battery and extending the life of the battery. In addition, the consumption of the battery can be suppressed and the fuel consumption can be kept good.

  Next, the best mode for carrying out the present invention will be described with reference to the drawings.

  FIG. 1 is a system configuration diagram of a starter for a flexible fuel vehicle according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a spark ignition type four-cylinder reciprocating engine. The engine 1 includes a combustion chamber 11 (only one portion is shown in FIG. 1) for each cylinder. The passage 12 and the exhaust passage 13 communicate with each other.

  A fuel injection valve 14 (only one place is shown in FIG. 1) for injecting and supplying alcohol fuel as fuel to the combustion chamber 11 of each cylinder is attached to the intake passage 12. Then, an air-fuel mixture comprising alcohol fuel injected from each fuel injection valve 14 and outside air introduced into the intake passage 12 is introduced into each combustion chamber 11. In order to ignite the air-fuel mixture introduced into each combustion chamber 11, an ignition plug 15 (only one place is shown in FIG. 1) is attached to the engine 1. The spark plug 15 is driven based on the ignition signal distributed by the distributor. The distributor distributes the high voltage output from the igniter to the spark plug 15 in synchronization with the crank angle of the engine 1. Then, the air-fuel mixture introduced into the combustion chamber 11 by the ignition of the spark plug 15 is exploded and burned, and the driving force of the engine 1 is obtained. Thus, the combustion gas generated in the combustion chamber 11 is discharged to the outside through the exhaust passage 13.

  Next, a schematic configuration of a fuel supply system for supplying alcohol fuel to the fuel injection valve 14 will be described. FIG. 2 is a system configuration diagram showing the fuel supply system.

  As shown in FIG. 2, the fuel supply system 2 includes a feed pump 22 that feeds alcohol fuel from a fuel tank 21 that stores alcohol fuel, and pressurizes the alcohol fuel fed by the feed pump 22 to fuel each cylinder. And a high-pressure fuel pump 23 that discharges toward the injection valve 14.

  As a schematic configuration of the high-pressure fuel pump 23, a cylinder 231, a plunger 232, a pressurizing chamber 233 and an electromagnetic spill valve 234 are provided. The plunger 232 is driven by the rotation of a drive cam 161 attached to the exhaust camshaft 16 of the engine 1 and reciprocates in the cylinder 231. By the reciprocating movement of the plunger 232, the volume of the pressurizing chamber 233 is enlarged or reduced. In the present embodiment, two cam peaks (cam noses) 161 a and 161 a are formed on the drive cam 161 with an angular interval of 180 ° around the rotation axis of the exhaust cam shaft 16. The plungers 232 are pushed up by the cam noses 161 a and 161 a so that the plungers 232 move in the cylinder 231. In addition, since the engine according to the present embodiment is a four-cylinder type, each time from the fuel injection valve 14 provided for each cylinder during one cycle of the engine 1, that is, while the crankshaft 17 rotates twice, A total of four fuel injections will be performed. In this engine, the exhaust camshaft 16 makes one revolution every time the crankshaft 17 makes two revolutions. Therefore, the fuel injection from the fuel injection valve 14 is performed four times, and the discharge operation from the high-pressure fuel pump 23 is performed twice, every cycle of the engine 1.

  The pressurizing chamber 233 is partitioned by a plunger 232 and a cylinder 231. The pressurizing chamber 233 communicates with the feed pump 22 through the low pressure fuel pipe 24 and communicates with the inside of the delivery pipe 26 through the high pressure fuel pipe 25.

  The fuel injection valves 14, 14,... Are connected to the delivery pipe 26, and a fuel pressure sensor 261 for detecting the fuel pressure (actual fuel pressure) in the delivery pipe 26 is disposed. A return pipe 263 is connected to the delivery pipe 26 via a relief valve 262. The relief valve 262 opens when the pressure of the alcohol fuel in the delivery pipe 26 exceeds a predetermined pressure (for example, 13 MPa). By opening the valve, a part of the alcohol fuel stored in the delivery pipe 26 is returned to the fuel tank 21 via the return pipe 263. Thereby, an excessive increase in the pressure of the alcohol fuel in the delivery pipe 26 is prevented.

  The low pressure fuel pipe 24 is provided with a pressure regulator 241. The pressure regulator 241 returns the alcohol fuel in the low-pressure fuel pipe 24 to the fuel tank 21 when the pressure of the alcohol fuel in the low-pressure fuel pipe 24 exceeds a predetermined pressure (for example, 0.4 MPa). The pressure of the alcohol fuel in the pipe 24 is maintained below a predetermined pressure. The low pressure fuel pipe 24 is provided with a pulsation damper 242, and the pulsation damper 242 suppresses fuel pressure pulsation in the low pressure fuel pipe 24 when the high pressure fuel pump 23 is operated. . The high-pressure fuel pipe 25 is provided with a check valve 251 for preventing the alcohol fuel discharged from the high-pressure fuel pump 23 from flowing backward.

  The high-pressure fuel pump 23 is provided with the electromagnetic spill valve 234 for communicating or blocking between the low-pressure fuel pipe 24 and the pressurizing chamber 233. The electromagnetic spill valve 234 includes an electromagnetic solenoid 234a, and opens and closes by controlling energization of the electromagnetic solenoid 234a. The electromagnetic spill valve 234 is opened by the biasing force of the coil spring 234b when energization to the electromagnetic solenoid 234a is stopped. Hereinafter, the opening / closing operation of the electromagnetic spill valve 234 will be described. Hereinafter, the opening / closing operation of the electromagnetic spill valve 234 will be described with reference to FIG.

  First, when the energization of the electromagnetic solenoid 234a is stopped, the electromagnetic spill valve 234 is opened by the urging force of the coil spring 234b, and the low-pressure fuel pipe 24 and the pressurizing chamber 233 communicate with each other. In this state, when the plunger 232 moves in the direction in which the volume of the pressurizing chamber 233 increases (suction stroke), the alcohol fuel fed from the feed pump 22 enters the pressurizing chamber 233 via the low-pressure fuel pipe 24. Inhaled.

  On the other hand, when the plunger 232 moves in the direction in which the volume of the pressurizing chamber 233 contracts (pressurization stroke), the electromagnetic spill valve 234 closes against the urging force of the coil spring 234b by energizing the electromagnetic solenoid 234a. Then, the low-pressure fuel pipe 24 and the pressurizing chamber 233 are disconnected from each other, and the check valve 252 is opened when the pressure of the alcohol fuel in the pressurizing chamber 233 reaches a predetermined value. It is discharged toward the delivery pipe 26 through the fuel pipe 25.

  The adjustment of the discharge amount of alcohol fuel in the high-pressure fuel pump 23 is performed by controlling the valve closing period of the electromagnetic spill valve 234 in the pressurization stroke. That is, if the valve closing start time of the electromagnetic spill valve 234 is advanced and the valve closing period is lengthened, the alcohol fuel discharge amount increases. If the valve closing start time of the electromagnetic spill valve 234 is delayed and the valve closing period is shortened, the alcohol fuel is discharged. The discharge amount decreases. Thus, the pressure of the alcohol fuel in the delivery pipe 26 is controlled by adjusting the discharge amount of the alcohol fuel from the high-pressure fuel pump 23. The valve closing period of the electromagnetic spill valve 234 is controlled by controlling energization from an engine ECU (Electronic Control Unit) 3 having a CPU to the electromagnetic solenoid 234a.

  Here, the pump duty DT, which is a control amount for controlling the discharge amount of alcohol fuel from the high-pressure fuel pump 23 (the closing timing of the electromagnetic spill valve 234), will be described.

  This pump duty DT varies between 0 and 100%, and is a value related to the cam angle of the drive cam 161 of the exhaust camshaft 16 corresponding to the valve closing period of the electromagnetic spill valve 234. .

  Specifically, with respect to the cam angle of the drive cam 161, as shown in FIG. 3, the cam angle (maximum cam angle) corresponding to the maximum valve closing period of the electromagnetic spill valve 234 is θ0, and the target of the maximum valve closing period is set. Assuming that the cam angle (target cam angle) corresponding to the fuel pressure is θ, the pump duty DT is expressed by the ratio of the target cam angle θ to the maximum cam angle θ0 (DT = θ / θ0). Therefore, the pump duty DT becomes a value closer to 100% as the valve closing period (the valve closing start timing) of the target electromagnetic spill valve 234 approaches the maximum valve closing period, and the target valve closing period becomes “0”. The closer it is, the closer to 0%.

  Then, as the pump duty DT approaches 100%, the valve closing start timing of the electromagnetic spill valve 234 adjusted based on the pump duty DT is advanced, and the valve closing period of the electromagnetic spill valve 234 becomes longer. As a result, the amount of alcohol fuel discharged from the high-pressure fuel pump 23 increases and the actual fuel pressure rises. Further, as the pump duty DT approaches 0%, the closing timing of the electromagnetic spill valve 234 adjusted based on the pump duty DT is delayed, and the closing period of the electromagnetic spill valve 234 is shortened. As a result, the amount of alcohol fuel discharged from the high-pressure fuel pump 23 decreases, and the actual fuel pressure decreases. The details of the procedure for calculating the pump duty DT are omitted here.

  Further, the fuel supply system 2 includes a heater 27 as a heating means for heating the alcohol fuel in the delivery pipe 26. The heater 27 is attached to the casing of the delivery pipe 26, and the alcohol fuel in the delivery pipe 26 is heated through the casing. The heater 27 is controlled by the engine ECU 3. Specifically, the heater 27 is connected to the battery BT via a preheat relay 28 and a resistance switching relay 29 as heat quantity selection means arranged in series with each other.

  The preheat relay 28 includes a solenoid 281 that is excited by a command from the engine ECU 3, and the preheat relay 28 is closed by the excitation of the solenoid 281.

  The resistance switching relay 29 includes a changeover switch 291. The changeover switch 291 includes a direct supply position (right position in FIG. 1) for directly supplying the current value Imax1 from the battery BT via the preheat relay 28 to the heater 27, and a switch from the battery BT via the preheat relay 28. The current value Imax2 is switched to two positions, that is, a resistance supply position (left position in FIG. 1) for supplying the heater 27 via the resistor 29a. The resistance switching relay 29 includes a solenoid 292 that is excited by a command from the engine ECU 3. The switching switch 291 is switched to the direct supply position by excitation of the solenoid 292, while the switching switch 291 is switched by demagnetization of the solenoid 292. It can be switched to the resistance supply position. As shown in FIG. 4, the engine ECU 3 includes a map showing the characteristics of the current values Imax1 and Imax2 for the heater 27 with respect to the preheating time. As shown in this map, the amount of heat of the heater 27 corresponds to the case where the current value (Imax1) is supplied directly from the direct supply position of the resistance switching relay 29 when the preheat relay 28 is closed, and the resistance of the resistance switching relay 29. The current value (Imax2) is different from the case where the current value (Imax2) is supplied from the supply position through the resistor 29a. The two different current values (Imax1> Imax2) are selected as appropriate, and the alcohol fuel in the delivery pipe 26 is selected. To heat up. Further, the alcohol fuel in the delivery pipe 26 heated by the heater 27 when the engine 1 is started at a low temperature is injected from the predetermined fuel injection valve 14 toward the combustion chamber 11 of the engine 1, thereby improving the startability of the engine 1. So that it is done.

  In this case, the amount of heat of the heater 27 to which the current value Imax1 is supplied directly from the direct supply position of the resistance switching relay 29 when the preheat relay 28 is closed is the current value from the resistance supply position of the resistance switching relay 29 via the resistor 29a. The value of the resistor 29a is set so that Imax2 is larger than the heat amount of the heater 27 to which Imax2 is supplied. In this case, the alcohol fuel in the delivery pipe 26 is heated by the heater 27 to which the current value Imax1 is directly supplied from the direct supply position of the resistance switching relay 29, while the resistance of the resistance switching relay 29 is increased. The heater 27 supplied with the current value Imax2 from the supply position via the resistor 29a is heated by about 10 ° C. The fuel injection valve 14 and the spark plug 15 for each combustion chamber 11 of each cylinder are also controlled by the engine ECU 3, and consist of alcohol fuel injected from each fuel injection valve 14 and outside air introduced into the intake passage 12. The air-fuel mixture is ignited when it is introduced into each combustion chamber 11.

  As shown in FIG. 1, the engine ECU 3 is provided with time selection means 30 for selecting the time during which the alcohol fuel in the delivery pipe 26 is heated by the heater 27. As shown in FIG. 4A, the time selection means 30 includes a first preheat time Tend1 and a second preheat time Tend2. In this case, the preheat time is a time required for heating the alcohol fuel to a temperature at which the engine 1 is smoothly driven even when the engine 1 is started. The preheat time Tend1 is set to a large value (for example, about 10 minutes). The time Tend2 is set to a small value (for example, about 5 minutes). The current value Imax1 is supplied to the heater 27 until the first preheating time Tend1 elapses, while the current value Imax2 is supplied to the heater 27 until the second preheating time Tend2 elapses. .

  As shown in FIG. 1, the engine ECU 3 is supplied with an output from a rotational speed detection sensor 31 that detects the rotational speed of the crankshaft 17, and in the water jacket formed in the cylinder block 18 of the engine 1. The output from the cooling water temperature sensor 32 as a cooling water temperature detecting means for detecting the temperature of the cooling water is input. Further, an ignition ON signal from an ignition switch 38 is input to the engine ECU 3. The engine ECU 3 is provided with a sleep timer 34 as a leaving time measuring means for measuring a leaving time Tsleep until the engine 1 is stopped and restarted last time. Further, the engine ECU 3 is directly connected to the battery BT and is connected to be connectable / disconnectable via the main relay 35, and the sleep timer 34 measures the leaving time Tsleep by the power supply from the battery BT. It is possible. In this case, the main relay 35 includes a solenoid 351 that is excited by a command from the engine ECU 3, and the main relay 35 is closed by the excitation of the solenoid 351.

  In addition, the engine ECU 3 receives alcohol fuel from the heater 27 at a low temperature start of the engine based on the temperature of the cooling water detected by the cooling water temperature sensor 32 and the leaving time Tsleep measured by the sleep timer 34. A heating degree determining means 36 for determining the heating degree is provided. Specifically, the degree-of-heating determination means 36 includes the solenoid 281 and the resistance switching relay of the preheat relay 28 based on the temperature of the cooling water detected by the cooling water temperature sensor 32 and the leaving time Tsleep measured by the sleep timer 34. An excitation command to 29 solenoids 292 is selectively performed. The selection of the first preheating time Tend1 or the second preheating time Tend2 by the time selection means 30 is also based on the temperature of the cooling water detected by the cooling water temperature sensor 32 and the standing time Tsleep measured by the sleep timer 34. It is determined.

  As shown in FIG. 1, a preheat switch for determining whether or not to perform preheat for starting the engine 1 by heating alcohol fuel with the heater 27 at the time of low temperature start of the engine 1 is provided in the driver seat of the flexible fuel vehicle. 37 is provided.

  Next, the flow of control when the engine ECU 3 performs preheating will be described based on the flowchart of FIG.

  First, in step ST1 of the flowchart of FIG. 5, it is determined whether or not the ignition ON signal from the ignition switch 38 has been input. If YES in step ST2, the process proceeds to step ST2 and the rotational speed is determined. It is determined whether or not the rotation speed (engine rotation speed) of the crankshaft 17 detected by the detection sensor 31 is equal to or higher than the engine minimum rotation speed Nmin (for example, 100 rpm).

  If the determination in step ST2 is YES when the engine speed is equal to or higher than the engine minimum speed Nmin, it is determined that the engine 1 has started, and the process proceeds to step ST3. In step ST3, the preheat switch 37 is operated by the driver. It is determined whether or not it is turned on.

  If the determination in step ST3 is YES when the preheat switch 37 is turned on, the solenoid 351 is excited and the main relay 35 is closed in step ST4. Then, in step ST5, initial processing is performed.

  After that, in step ST6, the neglected time Tsleep measured by the sleep timer 34 until the engine 1 is stopped and restarted is acquired. Next, in step ST7, the temperature value of the cooling water detected by the cooling water temperature sensor 32 is acquired.

  Then, in step ST8, it is determined whether or not the leaving time Tsleep acquired in step ST6 is equal to or longer than a predetermined leaving time Tstd (for example, 20 hours). If the determination in step ST8 is YES when the leaving time Tsleep is equal to or longer than the predetermined leaving time Tstd, the preheat time Tend1 is set to a large value in step ST9. In this case, the preheat time Tend1 is a preheat time selected based on the temperature of the cooling water acquired in step ST7 in addition to the standing time Tsleep acquired in step ST6.

  Thereafter, in step ST10, the first preheat control is performed until the preheat time Tend1 set in step ST9 elapses. Specifically, as shown in FIG. 4B, until the preheating time Tend1 elapses, the solenoid 281 of the preheating relay 28 is excited to close the preheating relay 28, and the resistance switching relay 29 The solenoid 292 is excited to switch the changeover switch 291 to the direct supply position (right position in FIG. 1). As a result, the alcohol fuel in the delivery pipe 26 is heated until the preheat time Tend1 elapses by the amount of heat of the heater 27 to which the current value Imax1 is supplied directly from the direct supply position of the resistance switching relay 29 when the preheat relay 28 is closed. To do.

  On the other hand, if the determination in step ST8 is NO when the leaving time Tsleep is less than the predetermined leaving time Tstd, the preheating time Tend2 is set to a small value in step ST11. In this case, the preheat time Tend2 is a preheat time selected based on the temperature of the cooling water acquired in step ST7 in addition to the standing time Tsleep acquired in step ST6.

  Then, in step ST12, the second preheat control is performed until the preheat time Tend2 set in step ST11 elapses. Specifically, as shown in FIG. 4B, until the preheat time Tend2 elapses, the solenoid 281 of the preheat relay 28 is excited to close the preheat relay 28, and the resistance switching relay 29 The solenoid 292 is demagnetized and the changeover switch 291 is switched to the resistance supply position (left position in FIG. 1). As a result, the preheat time Tend2 passes through the alcohol fuel in the delivery pipe 26 by the heat amount of the heater 27 to which the current value Imax2 is supplied from the resistance supply position of the resistance switching relay 29 via the resistor 29a when the preheat relay 28 is closed. Heat until

  Thus, in the above embodiment, the degree of heating by which the alcohol fuel in the delivery pipe 26 is heated by the heater 27 when the engine 1 is started at a low temperature is determined by the temperature of the cooling water from the cooling water temperature sensor 32 and the previous engine 1 being stopped. The preheating time Tend1 (or preheating time Tend2) selected by the time selecting means 30 and the direct supply position by the resistance switching relay 29 (or selected based on the neglected time Tsleep measured by the sleep timer 34 from the start to restart Resistance supply position). For this reason, the cylinder block 18 is started at a low temperature of the engine 1 which has been left for about 12 hours when the temperature of the cooling water becomes the lower limit temperature, as in the case where the alcohol fuel is heated by the heater using only the temperature of the cooling water as a parameter. The alcohol fuel is not heated excessively ignoring the internal residual heat. Thereby, excessive heating of the alcohol fuel is eliminated when the engine 1 is started at a low temperature, the burden on the battery BT is reduced, and the life of the battery can be extended. In addition, the consumption of the battery BT due to excessive heating of the alcohol fuel is suppressed, and the burden of replenishing the total current value consumed by the battery BT while the vehicle is running is reduced, so that the fuel efficiency can be kept good.

  In addition, this invention is not limited to the said embodiment, The other various modifications are included. For example, in the above embodiment, the case where alcohol fuel is used as the main fuel has been described, but it is needless to say that the present invention can also be applied to the case where kerosene, light oil, or the like is used as the main fuel.

  Moreover, in the said embodiment, although the time selection means 30 which heats the alcohol fuel in the delivery pipe 26 by the mutually different 1st and 2nd preheating time Tend1, Tend2, the time selection means which has three or more types of preheating time is provided. The alcohol fuel in the delivery pipe may be heated with different preheating times. In the above embodiment, the resistance switching relay 29 appropriately selects two kinds of heat amounts to heat the alcohol fuel in the delivery pipe 26. However, the resistance switching relay 29 heats the alcohol fuel in the delivery pipe 26. The amount of heat may be selected as appropriate so that the alcohol fuel in the delivery pipe is heated. The alcohol fuel in the delivery pipe is heated by appropriately selecting from a plurality of resistance switching relays that switch three or more current values for the time selection means or the heater having three or more types of preheating times. You may do it. Furthermore, the alcohol fuel in the delivery pipe can be obtained by combining a time selection means having three or more types of preheating time and a plurality of resistance switching relays for switching three or more types of current values with respect to the heater, and selecting appropriately from the combination. May be heated.

  In the above embodiment, the predetermined leaving time Tstd to be compared with the leaving time is set to 20 hours, for example, but may be any time as long as it is 12 hours or more and less than 24 hours. Further, when the alcohol fuel in the delivery pipe is appropriately selected from at least one of the three or more types of preheating time and the three or more types of current values, the predetermined time for comparison with the standing time is used. There are two or more types of standing time (for example, 15 hours and 20 hours).

  In the above embodiment, the feed pump 22 and the high-pressure fuel pump 23 are provided in the fuel supply system 2 that supplies alcohol fuel from the alcohol fuel tank 21 to the delivery pipe 26. However, alcohol fuel is supplied from the alcohol fuel tank to the delivery pipe. Any fuel supply system may be used, and the present invention is not limited to this.

  Furthermore, although the case where it applied to the engine 1 of 4 cylinders was described in the said embodiment, it cannot be overemphasized that you may apply to the engine of the number of cylinders other than this.

1 is a system configuration diagram of a starting device for a flexible fuel vehicle according to an embodiment of the present invention. It is a figure which shows typically the structure of a fuel supply system. It is a figure for demonstrating the opening / closing operation | movement of an electromagnetic spill valve. (A) is a characteristic diagram which shows the characteristic of the heater electric current value with respect to preheating time, (b) is individual in the case of performing 1st and 2nd preheating control based on the leaving time in the case of performing preheating at the time of low temperature start of an engine It is a time chart figure of the solenoid of a preheat switch, a main relay, a solenoid of a preheat relay, and a resistance change relay. It is a flowchart figure which shows the flow of control at the time of performing preheating by engine ECU.

Explanation of symbols

1 Engine 27 Heater (heating means)
29 Resistance switching relay (heat quantity selection means)
30 hour selection means 32 Cooling water temperature sensor (cooling water temperature detection means)
34 Sleep timer (Leaving time measurement means)
36 Heating degree determining means Tsleep Leaving time

Claims (3)

In a flexible fuel vehicle starter that heats the fuel when starting the engine at a low temperature to improve the startability of the engine,
A neglecting time measuring means for measuring the neglecting time until the engine is restarted after being stopped last time;
Cooling water temperature detecting means for detecting the temperature of the cooling water;
Heating means for heating the fuel;
A heating degree determining means for determining the degree of heating of the fuel by the heating means at a low temperature start of the engine based on the temperature of the cooling water detected by the cooling water temperature detecting means and the leaving time measured by the standing time measuring means. And a starter for a flexible fuel vehicle. The starting device for a flexible fuel vehicle according to claim 1,
The heating means includes a calorific value selecting means for selecting a calorific value for heating the fuel,
A flexible fuel vehicle starting device, wherein the degree of heating of the fuel by the heating degree determining means is selected by the heat quantity selecting means. In the starting device of the flexible fuel vehicle according to claim 1 or 2,
The heating means has time selection means for selecting a time for heating the fuel,
The flexible fuel vehicle starter according to claim 1, wherein the heating degree determination means selects the fuel heating degree by the time selection means.

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