JP4725564B2 - Fuel injection device for internal combustion engine and fuel injection valve thereof - Google Patents

Description

  The present invention relates to a fuel injection device applied to an internal combustion engine that injects two types of fuel separately, and a fuel injection valve thereof.

  2. Description of the Related Art A fuel injection device for an internal combustion engine that injects two different types of fuel such as a high cetane number fuel and a low cetane number fuel into a combustion chamber at a ratio corresponding to the operating state of the internal combustion engine is known (for example, Patent Document 1). And 2). An apparatus is also known in which two types of fuel are introduced into a fuel tank for mixing at a ratio corresponding to the operating state of the engine, and the fuel mixed in the fuel tank is supplied to a combustion chamber (see, for example, Patent Document 3). ). In addition, Patent Documents 4 to 28 exist as prior art documents related to the present invention.

Special Table 2003-522877 JP-A-9-68061 JP 2004-308423 A JP 2004-169620 A Japanese Patent Publication No. 6-103013 JP 2004-360599 A JP-A-6-26376 JP-A-8-93535 JP-A-7-259687 JP-A-9-42103 Japanese Patent Laid-Open No. 2001-234829 Japanese Utility Model Publication 3-41068 Japanese Patent No. 2611345 Japanese Utility Model Publication No. 61-84166 Japanese Patent Laid-Open No. 1-116279 JP-A-5-231199 JP-A-6-10787 JP 2001-5070 A JP 2005-127196 A Japanese Patent No. 332578 Japanese Patent Publication No.3-1505 Japanese Patent Laid-Open No. 11-166432 Japanese Patent Publication No. 61-27583 Japanese Patent No. 3181104 JP 2004-76736 A JP-A-6-147437 JP 2004-144345 A JP 2005-214079 A

  In recent years, GTL (abbreviation of Gas to Liquids) fuel has attracted attention as a fuel for internal combustion engines. GTL fuel is a fuel that is synthesized and liquefied by generating synthesis gas such as CO and hydrogen from natural gas / biomass and reacting on a catalyst, and contains sulfur and aroma, mainly saturated hydrocarbons. Therefore, it is advantageous for realizing low emission, and also has a high cetane number because it has a linear saturated hydrocarbon structure. However, it is difficult for GTL fuel to cover the same amount as existing light oil due to its cost problems, and it is necessary to consider using it together with light oil. However, even if GTL and light oil are mixed and used in a fuel tank, the effect of GTL cannot be sufficiently obtained unless mixed with very poor light oil. Therefore, it is desirable to inject GTL and light oil separately, but a fuel injection valve having such a function has not been proposed yet. Patent Document 1 discloses a fuel injection device that injects two types of fuel from a single fuel injection valve, but only shows the vicinity of the injection hole at the tip of the fuel injection valve. The specific configuration such as the internal structure of is not disclosed. In addition, there is no prior art document that discloses a specific structure of a fuel injection device that injects two types of fuel independently from each other from a common fuel injection valve.

  Accordingly, an object of the present invention is to provide a fuel injection device that injects two types of fuel such as GTL and light oil independently from each other from a common fuel injection valve, and a fuel injection valve suitable for the injection device. .

A first fuel injection device according to the present invention is a fuel injection device for an internal combustion engine that injects different first fuel and second fuel into a cylinder from a common fuel injection valve. A first valve chamber on the center side, a second valve chamber partitioned by a partition wall with respect to the first valve chamber on the outer peripheral side, and a first jet communicating with the first valve chamber at the tip. A valve body provided with a hole and a second injection hole communicating with the second valve chamber, a first valve body disposed in the first valve chamber so as to be able to open and close the first injection hole, A second valve body disposed in the second valve chamber so as to be able to open and close the second nozzle hole; a first drive mechanism for opening and closing the first valve body; and the first valve by the first drive mechanism A second drive mechanism for opening and closing the second valve body independently of the body drive, and the first valve chamber or the second valve Any said in one of the valve chamber first one of the fuel, the other of the valve chamber is guided each other fuel, the first valve chamber or one of the valve chamber of the second valve chamber The first fuel is led to the other valve chamber, and the second fuel is led to the other valve chamber, respectively, and the first fuel and the second fuel are respectively sent to the first valve chamber and the second valve chamber. And a second state in which either one of the first fuel or the second fuel is led to both the first valve chamber and the second valve chamber. And a fuel supply switching means for switching between the first valve chamber and the second valve chamber, wherein the partition wall of the fuel injection valve partitions the first valve chamber and the second valve chamber, A movable partition wall that is movable between an open position and a fuel inlet for one of the valve chambers. Thus, the fuel supply switching means functions as a part of the fuel supply means, and the fuel supply switching means is provided with a partition drive mechanism that drives the movable partition between the closed position and the open position. Thus , the above-described problem is solved (claim 1).

According to the first fuel injection device of the present invention, when the first valve body is driven to open and close by the first drive mechanism of the fuel injection valve, the fuel guided to the first valve chamber is the first injection hole of the valve body. If the second valve body is driven to open and close by the second drive mechanism, the fuel guided to the second valve chamber is injected from the second injection hole of the same valve body. Thereby, two different types of fuel can be injected independently of each other. Further, by selecting the first state, the first fuel and the second fuel can be injected independently from each injection hole. On the other hand, when the second state is selected, one fuel can be injected from both the first injection hole and the second injection hole. Therefore, it is necessary by selecting the second state in an operating state in which the injection ratio of either one of the fuels is set to 100% and it is difficult to inject the required amount of fuel with only one injection hole. An amount of fuel can be reliably injected. Further, when the movable partition wall is held in the closed position, both valve chambers are partitioned from each other, and different fuel is injected from each nozzle hole. On the other hand, when the movable partition is switched to the open position, the space between the two valve chambers is opened and the fuel inlet to one of the valve chambers is closed, so that the fuel guided to the other valve chamber is injected from both nozzle holes. The

A second fuel injection device of the present invention is a fuel injection device for an internal combustion engine that injects a first fuel and a second fuel, which are different from each other, into a cylinder from a common fuel injection valve. A first valve chamber on the center side, a second valve chamber partitioned by a partition wall with respect to the first valve chamber on the outer peripheral side, and a first jet communicating with the first valve chamber at the tip. A valve body provided with a hole and a second injection hole communicating with the second valve chamber, a first valve body disposed in the first valve chamber so as to be able to open and close the first injection hole, A second valve body disposed in the second valve chamber so as to be able to open and close the second nozzle hole; a first drive mechanism for opening and closing the first valve body; and the first valve by the first drive mechanism A second drive mechanism for opening and closing the second valve body independently of the body drive, and the first valve chamber or the second valve The first fuel is led to one of the valve chambers, the second fuel is led to the other valve chamber, and the first fuel and the second fuel are led to the first valve chamber and One of the first state of the second valve chamber and the first fuel or the second fuel is supplied to the first valve chamber and the second valve chamber. Fuel supply switching means for switching between a second state leading to both; first pressure boosting means for boosting the first fuel; and second pressure boosting means for boosting the second fuel; The supply switching means includes a neutral position in which fuel boosted by each of the first boosting means and the second boosting means is separated from each other and led to the first valve chamber and the second valve chamber, and the first boosting means Alternatively, the fuel boosted by one of the boosting means of the second boosting means is used as the first boosting fuel. By providing a flow path switching valve that can be switched between an operating position that leads to both the chamber and the second valve chamber while blocking the passage of fuel boosted by the other boosting means. This problem is solved (claim 2).

According to the second fuel injection device of the present invention, when the first valve body is driven to open and close by the first drive mechanism of the fuel injection valve, the fuel guided to the first valve chamber is the first injection hole of the valve body. If the second valve body is driven to open and close by the second drive mechanism, the fuel guided to the second valve chamber is injected from the second injection hole of the same valve body. Thereby, two different types of fuel can be injected independently of each other. Further, by selecting the first state, the first fuel and the second fuel can be injected independently from each injection hole. On the other hand, when the second state is selected, one fuel can be injected from both the first injection hole and the second injection hole. Therefore, it is necessary by selecting the second state in an operating state in which the injection ratio of either one of the fuels is set to 100% and it is difficult to inject the required amount of fuel with only one injection hole. An amount of fuel can be reliably injected. Further, different fuels are introduced into the valve chambers when the flow path switching valve is held in the neutral position, and the same fuel is introduced into both valve chambers when the flow path switching valve is switched to the operating position.

In the fuel injection valve of the present invention, a first valve chamber is provided on the center side, a second valve chamber partitioned by a partition wall with respect to the first valve chamber is provided on the outer peripheral side, and the first valve chamber is provided at the tip portion. A valve main body provided with a first nozzle hole communicating with the valve chamber and a second nozzle hole communicating with the second valve chamber, and disposed in the first valve chamber so that the first nozzle hole can be opened and closed. A first valve body, a second valve body disposed in the second valve chamber so as to be able to open and close the second nozzle hole, a first drive mechanism for opening and closing the first valve body, and the first A second drive mechanism that opens and closes the second valve body independently of driving the first valve body by a drive mechanism, and the partition partitions the first valve chamber and the second valve chamber. Between a closed position and an open position that opens between the first valve chamber and the second valve chamber and closes the fuel inlet to one of the valve chambers. Is configured as a rotatably movable partition wall, and by further comprising a partition wall driving mechanism for driving between said open position said movable partition wall and the closed position, to solve the problems described above (claim 3).

According to the fuel injection valve of the present invention, by introducing different fuels into the first valve chamber and the second valve chamber, two types of fuel can be injected independently from the common fuel injection valve. Further, when the movable partition wall is held in the closed position, both valve chambers are partitioned from each other, and different fuel is injected from each nozzle hole. On the other hand, when the movable partition is switched to the open position, the space between the two valve chambers is opened and the fuel inlet to one of the valve chambers is closed, so that the fuel guided to the other valve chamber is injected from both nozzle holes. The

  As described above, according to the present invention, when the first valve body is driven to open and close by the first drive mechanism of the fuel injection valve, the fuel guided to the first valve chamber is the first injection hole of the valve body. If the second valve body is driven to open and close by the second drive mechanism, the fuel guided to the second valve chamber is injected from the second injection hole of the same valve body, so that two types of different fuels Can be injected independently of each other.

[First embodiment]
FIG. 1 shows a first embodiment in which a fuel injection device according to the present invention is applied to a diesel engine (hereinafter simply referred to as an engine) as an internal combustion engine. The engine 1 is mounted on a vehicle as a power source for traveling, and includes a plurality of (four in the figure) cylinders 2 arranged in a line in the left-right direction in the figure, and an intake passage that guides intake air into the cylinders 2. 3, an exhaust passage 4 through which exhaust from the cylinder 2 is guided, and a turbocharger 5 provided between the intake passage 3 and the exhaust passage 4. An air cleaner 6 for filtering the intake air and an air flow meter 7 for detecting the intake air amount are provided upstream of the compressor 5a in the intake passage 3. An intake throttle valve 8 for adjusting the intake air amount is provided on the downstream side of the compressor 5a. On the other hand, at least one exhaust purification catalyst 9 is provided in the exhaust passage 4 on the downstream side of the turbine 5b. An EGR passage 10 is connected to the exhaust manifold 4 a of the exhaust passage 4. A part of the exhaust discharged from the cylinder 2 to the exhaust manifold 4a sequentially passes through the EGR cooler 11 and the EGR valve 12 in the EGR passage 10 and returns between the intake throttle valve 8 in the intake passage 3 and the intake manifold 3a.

  A fuel tank 14 is provided in a vehicle on which the engine 1 is to be mounted. The fuel tank 14 is provided with a first storage chamber 15 that stores GTL fuel as the first fuel, and a second storage chamber 16 that stores light oil as the second fuel. Each fuel in the fuel tank 14 is injected into the cylinder 2 of the engine 1 by the fuel injection device 20. The fuel injection device 20 sucks the GTL fuel in the first storage chamber 15 through the segmenter 17 and boosts the first fuel pump 21 as a first boosting unit that boosts the pressure, and the light oil in the second storage chamber 16 through the segmenter 17. A second fuel pump 22 as a second boosting means for sucking and boosting, a first common rail 23 for storing high-pressure GTL fuel sent from the first fuel pump 21, and a high-pressure light oil sent from the second fuel pump 22 are stored. A second common rail 24 and a fuel injection valve 25 that is connected to the common rails 23 and 24 and injects GTL fuel and light oil into the cylinder 2 are provided. The fuel injection valve 25 is provided for each cylinder 2. Each fuel injection valve 25 has a function of independently injecting GTL fuel and light oil into the cylinder 2. Between the fuel injection valve 25 and the storage chambers 15 and 16 of the fuel tank 14, return pipes 18 and 19 for returning excess fuel are provided, respectively.

  Next, details of the fuel injection valve 25 will be described. As shown in FIG. 2, the fuel injection valve 25 includes a valve main body 31 that functions as an entire casing of the fuel injection valve 25, and a first needle 32 and a second second valve body built in the valve main body 31. A second needle 33 as a valve body, a first drive mechanism 34 that drives the first needle 32, and a second drive mechanism 35 that drives the second needle 33 are provided. The first needle 32 has a solid shaft shape, and the second needle 33 has a hollow cylindrical shape. A first valve chamber 36 is provided on the center side of the distal end portion (lower end portion in FIG. 2) 31a of the valve main body 31, and a second valve chamber 37 is provided on the outer peripheral side. These valve chambers 36 and 37 are partitioned by a partition wall 38 so that fuel cannot flow. The tip 31a of the valve body 31 is formed in a tapered cone shape, and the tip 31a has a first injection hole 39 that communicates with the first valve chamber 36 and a second injection hole 40 that communicates with the second valve chamber 37. Each is provided. The first needle 32 is disposed in the first valve chamber 36 so as to be movable in the direction of the center line CL of the fuel injection valve 25 by fitting the piston flange 32a at the rear end thereof to the inner peripheral surface 38a of the partition wall 38. Has been. The second needle 33 is disposed in the second valve chamber 37 so as to be movable in the direction of the center line CL by being fitted to the outer peripheral surface 38 b of the partition wall 38. When the first needle 32 moves to the distal end side of the valve body 31, the first injection hole 39 is closed by the tapered surface 32b at the distal end of the first needle 32, and the first needle 32 is moved to the rear end side (see FIG. 2, the first nozzle hole 39 is opened. On the other hand, when the second needle 33 moves to the distal end side of the valve body 31, the second injection hole 40 is closed by the tapered surface 33 b at the distal end of the second needle 33, and the second needle 33 is moved to the rear end side of the valve body 31. When it moves to (the upper end side in FIG. 2), the second nozzle hole 40 opens.

  The first drive mechanism 34 is slidably fitted to a first needle return spring 42 that presses the first needle 32 toward the tip 31 a of the valve body 31 and a first cylinder 43 of the valve body 31. A piston 44, a first outer valve 46 disposed in the first solenoid chamber 45 of the valve body 31, a first outer valve return spring 47 that presses the first outer valve 46 toward the first cylinder 43, and a first outer valve return thereof And a first solenoid coil 48 disposed on the outer periphery of the spring 47. The first command piston 44 divides the interior of the first cylinder 43 into a first spring chamber 43a on the front end side and a first command chamber 43b on the rear end side. A small-diameter needle holding shaft 44 a is provided on the distal end side of the first command piston 44. The needle holding shaft 44 a can come into contact with the rear end of the first needle 32 when the first needle 32 closes the first injection hole 39. A first high pressure fuel passage 50 is connected to the first command chamber 43 b via a first orifice 51. The first high-pressure fuel passage 50 is formed in the valve main body 31, and a part thereof communicates with the first valve chamber 36. The first command chamber 43 b communicates with the first solenoid chamber 45 through the second orifice 52. The inner diameter of the second orifice 52 is set smaller than the inner diameter of the first orifice 51. Further, each of the first spring chamber 43 a and the first solenoid chamber 45 is connected to a first low-pressure fuel passage 53 formed in the valve body 31.

  The first outer valve 46 is made of a magnetic material. When the first solenoid coil 48 is in a non-excited state, the first outer valve 46 is held at a position where the second orifice 52 is closed by the spring force of the first outer valve return spring 47. In this case, the space between the first command chamber 43b and the first low-pressure fuel passage 53 is closed. On the other hand, when the first solenoid coil 48 is excited, the first outer valve 46 is opened, whereby the first command chamber 43 b is connected to the first low-pressure fuel passage 53 via the second orifice 52 and the first solenoid chamber 45. Is done.

  Next, the second drive mechanism 35 is slidably fitted to the second needle return spring 62 that presses the second needle 33 toward the distal end portion 31 a of the valve body 31 and the second cylinder 63 of the valve body 31. A second command piston 64; a second outer valve 66 disposed in the second solenoid chamber 65 of the valve body 31; a second outer valve return spring 67 that presses the second outer valve 66 against the second cylinder 63; and a second outer valve. And a second solenoid coil 68 disposed on the outer periphery of the valve return spring 67. The inside of the second cylinder 63 is divided into a second spring chamber 63a on the front end side and a second command chamber 63b on the rear end side by the second command piston 64. A hollow needle holding shaft 64 a is provided on the distal end side of the second command piston 64. The needle holding shaft 64 a can come into contact with the rear end of the second needle 33 when the second needle 33 closes the second injection hole 40. A second high pressure fuel passage 70 is connected to the second command chamber 63 b via a first orifice 71. The second high-pressure fuel passage 70 is formed in the valve body 31, and a part of the second high-pressure fuel passage 70 communicates with the second valve chamber 37. The second command chamber 63 b communicates with the second solenoid chamber 65 through the second orifice 72. The inner diameter of the second orifice 62 is set smaller than the inner diameter of the first orifice 61. Further, each of the second spring chamber 63 a and the second solenoid chamber 65 is connected to a second low-pressure fuel passage 73 formed in the valve body 31.

  The second outer valve 66 is made of a magnetic material. When the second solenoid coil 68 is in a non-excited state, the second outer valve 66 is held at a position where the second orifice 72 is closed by the spring force of the second outer valve return spring 67. In this case, the space between the second command chamber 63b and the second low pressure fuel passage 73 is closed. On the other hand, when the second solenoid coil 68 is excited, the second outer valve 66 is opened, so that the second command chamber 63b is connected to the second low-pressure fuel passage 73 via the second orifice 72 and the second solenoid chamber 65. Is done.

  In the fuel injection valve 25 having the above configuration, the first high-pressure fuel passage 50 and the second high-pressure fuel passage 70 are connected to different common rails 23 and 24, respectively. The correspondence relationship between the high-pressure fuel passages 50 and 70 and the common rails 23 and 24 can be determined from various viewpoints. Here, the first high-pressure fuel passage 50 and the first common rail 23 are connected, and the second high-pressure fuel passage is connected. The description will be continued assuming that 70 and the second common rail 24 are connected. In this case, the first low-pressure fuel passage 53 is connected to the first return pipe 18, and the second low-pressure fuel passage 73 is connected to the second return pipe 19.

  When the first high-pressure fuel passage 50 and the second high-pressure fuel passage 70 are connected to the common rails 23 and 24 as described above, the first common rail 23 is provided in the first valve chamber 36 and the first command chamber 43 b of the fuel injection valve 25. The high pressure GTL fuel stored in the second common pressure chamber 24 is introduced into the second valve chamber 37 and the second command chamber 63b. As shown in FIG. 2, when the solenoid coils 48 and 68 are respectively de-energized, the second orifices 52 and 72 are closed by the outer valves 46 and 66, respectively, so that the fuel pressure is applied to the command chambers 43b and 63b. Be trapped. As a result, the command pistons 44 and 64 are pushed out toward the distal end side of the fuel injection valve 25, and the needle holding shafts 44a and 64a push the needles 32 and 33 along with them, and the nozzle holes 39 and 40 are closed. In these states, no fuel is injected.

  On the other hand, when the solenoid coils 48 and 68 are energized, the outer valves 46 and 66 are attracted to the solenoid coils 48 and 68 as shown in FIG. 3, and the second orifices 52 and 72 are opened to open the command chambers 43b and 63b. The fuel flows out into the low pressure fuel passages 53 and 73, respectively. As a result, the pressure in the command chambers 43b and 63b decreases, and the force for pressing the needles 32 and 33 against the distal end side of the fuel injection valve 25 decreases. As a result, the needles 32 and 33 are pushed into the rear end portion of the fuel injection valve 25 by the pressure of the fuel acting on the piston flanges 32a and 33a, and the injection holes 39 and 40 are opened. As a result, GTL fuel is injected from the first injection hole 39 and light oil is injected from the second injection hole 40. The amount of fuel injected from the nozzle holes 39 and 40 can be appropriately adjusted by changing the length of time for supplying the exciting current to the solenoid coils 48 and 68 (on-duty ratio in the case of PWM control). In addition, by changing the supply of exciting currents to the first solenoid coil 48 and the second solenoid coil 68 independently of each other, the timing of fuel injection from each of the nozzle holes 39 and 40 can be set independently. Further, the ratio of the fuel injection amount (hereinafter referred to as the injection ratio) can also be changed.

  Next, control of the fuel injection valve 25 will be described. As shown in FIG. 1, a vehicle equipped with an engine 1 is provided with an engine control unit (ECU) 80 as a computer unit for controlling the operating state of the engine 1. The ECU 80 outputs a signal corresponding to the intake air amount output from the air flow meter 7, a signal corresponding to the crank angle output from the crank angle sensor 81 and the engine speed (rotation speed), and an accelerator opening sensor 82. Various calculations are executed with reference to a signal corresponding to the opening of the accelerator pedal, and the engine 1 is operated by operating control target devices such as the intake throttle valve 8, the EGR valve 12, and the fuel injection valve 25 according to the calculation results. Control the operating state to the target state.

  In order to control the fuel injection operation of the fuel injection valve 25, a first coil drive circuit 83 and a second coil drive circuit 84 are connected to the ECU 80. Although only one set of coil drive circuits 83 and 84 is shown in FIG. 1, one set of coil drive circuits 83 and 84 is provided for each fuel injection valve 25. The first coil drive circuit 83 switches supply and stop of excitation current from a power source (not shown) to the first solenoid coil 48 of the fuel injection valve 25 in accordance with an instruction from the ECU 80. The second coil drive circuit 84 In accordance with the instruction from, the supply of the excitation current to the second solenoid coil 68 of the fuel injection valve 25 from the power source and the supply stop are switched.

  In order to control the fuel injection ratio, the map shown in FIG. 4 is written as data in a storage device (eg, ROM) of the ECU 80. The map of FIG. 4 is a plot of the injection ratio between GTL fuel and light oil in association with the rotational speed of the engine 1 and the load of the engine 1. A thick line Ltq in the figure indicates the maximum torque of the engine 1. Further, the curve in the figure is an equal injection ratio line obtained by connecting points having the same injection ratio. In the map of FIG. 4, the light oil injection ratio is maximized in the high-load low-rotation region Za, and the GTL fuel injection ratio increases as the distance from the region Za increases. In the map of FIG. 4, if the operating state of the engine 1 is divided into a high load / high rotation region, a high load / low rotation region, a low load / high rotation region, and a low load / low rotation region, the tendency of the injection ratio of GTL fuel can be shown. It is as shown in the table.

  The reason for changing the injection ratio as described above is that it reflects the high cetane number of the GTL fuel and the characteristics that do not include the aroma component. In the high-load high-rotation region, the amount of fuel increases and the in-cylinder temperature (temperature in the cylinder 2) becomes relatively high, so the concern of pre-ignition caused by the high cetane number of GTL fuel is reduced. On the other hand, since the amount of fuel increases, so much GTL fuel increases the effect of suppressing soot due to the absence of aroma. Therefore, the injection ratio of GTL fuel is set to be large in the high load high rotation range. On the other hand, in the high-load low-rotation region, the in-cylinder temperature is lower than that during high rotation because of the low rotation. Therefore, premature ignition occurs under the influence of the high cetane number of GTL fuel, and there is a concern that diesel smoke may deteriorate due to low rotation and a small amount of intake air. Therefore, the injection ratio of the GTL fuel is set to be small in the high load low speed region. Next, in the low-load high-rotation region, ignition is relatively fast, but because of the high rotation, the intake air amount is large and the risk of deterioration of diesel smoke is low. And the effect that combustion noise falls under the influence of the high cetane number of GTL fuel becomes relatively large. Therefore, the injection ratio of GTL fuel is increased in the low load high rotation region as compared with the high load low rotation region. Further, in the low-load low-rotation region, the effect of reducing combustion noise is further increased by the influence of the high cetane number of the GTL fuel as in the low-load high-rotation region. Therefore, the injection ratio of GTL fuel is set to be larger in the low load / low rotation region than in the low load / high rotation region.

  In the map shown in FIG. 4, the injection ratio of any one of the fuels may be 100%, that is, only one of the fuels may be injected and the other fuel may not be injected. For example, there may be a case where only GTL fuel is injected in a high load high rotation region. Instead of the engine load, a map may be created using parameters correlated with the engine load.

  FIG. 5 shows a fuel injection control routine executed by the ECU 80 to control the injection of the GTL fuel and light oil of the fuel injection valve 25 using the map of FIG. The routine of FIG. 5 is repeatedly executed in synchronization with the fuel injection from the fuel injection valve 25. In the routine of FIG. 5, the ECU 80 first calculates the required fuel injection amount based on the accelerator opening detected by the accelerator opening sensor 82 in step S1. The calculation of the required injection amount may be the same as a known method. In the subsequent step S2, the ECU 80 determines the injection ratio between the GTL fuel and the light oil. That is, the ECU 80 obtains the rotation speed of the engine 1 with reference to the output of the crank angle sensor 81, obtains the load of the engine 1 with reference to the output of the accelerator opening sensor 82, and determines the rotation speed and load. The corresponding injection ratio is determined with reference to the data corresponding to the map of FIG. In the next step S3, the ECU 80 multiplies the required injection amount determined in the current routine by the injection ratio of each fuel to determine the respective injection amounts of GTL fuel and light oil. Thereby, ECU80 functions as an injection ratio determination means. At this time, the injection timing and the number of injections of each fuel are also determined. What is necessary is just to determine the injection timing and the frequency | count of injection similarly to a well-known method. So-called multi-stage injection in which at least one of GTL fuel and light oil is injected in a plurality of times may be performed.

  After completing the process of step S3, the ECU 80 proceeds to the next step S4 and executes fuel injection. That is, the ECU 80 determines the timing at which fuel injection should be started based on the signal of the crank angle sensor 81, and when the injection start timing arrives, each of the first coil drive circuit 83 and the second coil drive circuit 84 On the other hand, a valve opening signal having a length corresponding to the injection amount determined in step S3 is output. Thereby, ECU80 functions as an injection control means. By supplying an exciting current from the coil drive circuits 83 and 84 to the solenoid coils 48 and 68 of the fuel injection valve 25 for a time length according to the valve opening signal from the ECU 80, the injection ratio and the injection ratio corresponding to the operating state of the engine 1 and An injection amount of fuel is injected into the cylinder 2 from the fuel injection valve 25. After executing the fuel injection in step S4, the ECU 80 ends the current routine and starts the routine of FIG. 5 again prior to the next fuel injection timing. The excitation start timings of the solenoid coils 48 and 68 do not need to be synchronized. The excitation of the first solenoid coil 48 starts at a timing suitable for starting the injection of GTL fuel, and the second solenoid coil 68 The excitation may be started at a timing suitable for starting the injection of light oil.

  Next, the correspondence relationship between the first high-pressure fuel passage 50 and the second high-pressure fuel passage 70 of the fuel injection valve 25 and the common rails 23 and 24 will be described. The distance from the lower surface of the cylinder head to the injection holes 39 and 40 can be taken into consideration as one reference when considering which fuel the high pressure fuel passages 50 and 70 should be assigned to.

  As shown in FIG. 2, the points where the center lines La and Lb of the nozzle holes 39 and 40 intersect the center line CL of the fuel injection valve 25 are defined as the first nozzle hole center Pa and the second nozzle hole Pb, respectively. When this is done, there is a difference between the projection amounts Xa and Xb of the injection hole centers Pa and Pb from the lower surface A of the cylinder head to which the fuel injection valve 25 is attached. That is, the protrusion amount Xa related to the first nozzle hole 39 on the center side is larger than the protrusion amount Xb related to the second nozzle hole 40 on the outer peripheral side. On the other hand, as shown in the map of FIG. 4, the light oil injection ratio is set to be large in the high-load low-rotation region. Since the amount of movement of the piston during the fuel injection period is small in the low rotation region, most of the fuel injected from the fuel injection valve 25 is in the piston combustion chamber (that is, as shown in FIG. Is injected into the recess 26a) formed in This tendency becomes more prominent as the amount of protrusion at the center of the nozzle hole increases. For this reason, in the high-load and low-rotation region, when light oil is injected from the second injection hole 40 with a small projection amount at the center of the injection hole, the light oil overflows appropriately from the piston combustion chamber and promotes homogenization of the air-fuel mixture. Thus, the generation of soot is suppressed.

  On the other hand, in a high-load high-rotation region where the injection ratio of GTL fuel is large, the amount of movement of the piston during the fuel injection period is large, so that it is relatively difficult to inject fuel into the piston combustion chamber. In this case, the larger the amount of protrusion at the center of the nozzle hole is, the more advantageous is the use of air in the cylinder 2 and the suppression of soot formation and performance improvement. Accordingly, when paying attention to the amount of protrusion at the center of the nozzle hole, the first high-pressure fuel passage 50 is connected to the first common rail 23 for GTL fuel, the second high-pressure fuel passage 70 is connected to the second common rail 24 for light oil, respectively. It is considered preferable to inject GTL fuel from one injection hole 39 and light oil from the second injection hole 40, respectively. As shown in FIG. 6, the center line La of the first injection hole 39 and the center line Lb of the second injection hole 40 intersect each other until reaching the wall surface 26 b of the piston combustion chamber 26 a provided in the piston 26. It is desirable to form each nozzle hole 39, 40 so that it does not occur. Thereby, the collision of the sprays of both fuels can be suppressed and the homogenization of the air-fuel mixture in the cylinder 2 can be further promoted.

  As another standard regarding the correspondence relationship between the high-pressure fuel passages 50 and 70 and the fuel, the nozzle hole areas of the nozzle holes 39 and 40 may be considered. In addition, since the 1st nozzle hole 39 and the 2nd nozzle hole 40 are each provided with two or more, the nozzle hole area here is the sum total of the cross-sectional area of the 1st nozzle hole 39, and the sum total of the cross-sectional area of the 2nd nozzle hole 40. Means each value. As shown in the map of FIG. 4, the GTL fuel injection ratio is set to be large in the high-load high-rotation region, and the GTL fuel injection amount increases accordingly. In particular, when the injection ratio of GTL fuel is set to 100%, it is necessary to inject GTL fuel at a large flow rate. The injection amount of GTL fuel required in the high load high rotation region is larger than the injection amount of light oil required in the high load low rotation region. On the other hand, since the area of each of the first nozzle holes 39 and the second nozzle holes 40 has a size relationship with the circumferential lengths of the valve chambers 36 and 37, the first nozzle holes located on the center side. The second injection hole 40 located on the outer peripheral side than 39 is easier to ensure. Therefore, by connecting the first high-pressure fuel passage 50 to the second common rail 24 for light oil and connecting the second high-pressure fuel passage 70 to the first common rail 23 for GTL fuel, GTL fuel that requires a large flow rate is obtained. It can be considered that it is appropriate to inject from the second injection hole 40 and to inject the light oil from the first injection hole 39. In this case, the first low-pressure fuel passage 53 is connected to the second return pipe 19, and the second low-pressure fuel passage 73 is connected to the first return pipe 18.

  Even when the correspondence relationship between the fuel and the nozzle hole is determined in consideration of the nozzle hole area, the first needle on the center side of the fuel injection valve 25 is configured in a pintle valve form, so The holes 39 can also be assigned as GTL fuel injection holes. For example, as shown in FIG. 7, the tip of the first needle 32 protrudes from the tip of the valve body 31, and a flange 32c is provided at the protruding portion so as to surround the first needle 32 over the entire circumference. The first nozzle hole 39 can be formed. According to the configuration of FIG. 7, the circumferential direction length of the first nozzle hole 39 is increased to increase the nozzle hole area, and the nozzle hole area of the first nozzle hole 39 can be expanded more than the second nozzle hole 40. It becomes possible. According to the example of FIG. 7, the correspondence between the amount of protrusion at the center of the nozzle hole and the fuel can be set in the same manner as in FIG. In the configuration of FIG. 7, when the first needle 32 moves to the rear end side of the fuel injection valve 25 as indicated by a solid line in the drawing, the flange 32 c closes the first injection hole 39, and the first needle 32 is It is necessary to change the configuration of the first drive mechanism 34 so that the flange 32c is separated from the valve body 31 and the first injection hole 39 is opened when the fuel injection valve 25 moves to the front end side. Such a drive mechanism may be the same as the drive mechanism of a known pintle valve type fuel injection valve.

  Next, a modification of the common rail will be described. In FIG. 1, the first common rail 23 and the second common rail 24 are drawn as members independent from each other. However, as shown in FIG. 8, the partition extending inside the single tube 27 over the entire length in the longitudinal direction. In 27a, the first pressure chamber 27b and the second pressure chamber 27c are divided, and both ends of the pressure chambers 27b and 27c are closed. By storing in the two pressure chambers 27c, the tube 27 may function as a common common rail in which the first and second common rails are integrated. If the pressure difference between the GTL fuel and light oil stored in each of the pressure chambers 27b and 27c is set small, the wall thickness of the partition wall 27a can be reduced.

[Second form]
FIG. 9 shows a second embodiment in which the fuel injection device according to the present invention is applied to an engine. In FIG. 9, parts that are the same as those in FIG. 1 are given the same reference numerals, and the differences will be mainly described below. In the fuel injection device 20A of this embodiment, a bypass fuel passage 100 is provided between the discharge sides of the first fuel pump 21 for GTL fuel and the second fuel pump 22 for light oil. Further, as shown in FIG. 10, the bypass fuel passage 100 includes an electromagnetically driven first control valve 101 as a first on-off valve, and between the second fuel pump 22 and the second common rail 24. An electromagnetically driven second control valve 102 is provided as a second on-off valve. These control valves 101 and 102 are controlled to open and close from the ECU 80 via the electromagnetic valve drive circuit 103. For example, as shown in FIG. 11, the first control valve 101 uses a fuel pressure discharged from the first fuel pump 21 and a spring force of the return spring 101a to place a poppet type valve element 101b in the valve seat 101c. On the other hand, by applying an electromagnetic force Fs in the opposite direction to the valve stem 101d to separate the valve body 101b from the valve seat 101c, the first fuel pump 21 and the second common rail 24 are opened. Configured. The same configuration may be applied to the second control valve 102.

  According to the above configuration, when the first control valve 101 is closed and the second control valve 102 is opened, either the first high-pressure fuel passage 50 or the second high-pressure fuel passage 70 as in the first embodiment. GTL fuel and gas oil are supplied to the other (first state). By closing the second control valve 102 and opening the first control valve 101, high-pressure GTL fuel can be supplied to both the high-pressure fuel passages 50 and 70 of the fuel injection valve 25 (second state). That is, in this embodiment, the fuel supply switching means is realized by a combination of the bypass passage 100, the first control valve 101, and the second control valve 102. In the following description, it is assumed that the first common rail 23 for GTL fuel is connected to the first high-pressure fuel passage 50 and the second common rail 24 for light oil is connected to the second high-pressure fuel passage 70.

  FIG. 12 shows a fuel injection control routine that the ECU 80 executes instead of the routine of FIG. However, the same processes as those in FIG. 5 are denoted by the same reference numerals. In the fuel injection control routine of FIG. 12, the required injection amount of fuel corresponding to the accelerator opening is calculated in step S1, the injection ratio of GTL fuel and light oil is determined in accordance with the map of FIG. 4 in step S2, and each step in step S3. The fuel injection amount and the like are determined. In step S2, the GTL fuel injection ratio may be set to 100% in the high load high rotation range. After the injection amount of each fuel is determined in step S3, the ECU 80 proceeds to step S5 and injects only the GTL fuel, that is, the GTL fuel injection ratio is 100% and the required injection amount is It is determined whether or not a predetermined threshold value is exceeded. The threshold value is set to a maximum value of the amount of GTL fuel that can be injected from the first injection holes 39 or to a small value with some margin. When the first common rail 23 for GTL fuel is connected to the second high-pressure fuel passage 70, the maximum amount of GTL fuel that can be injected from the second injection hole 40 or a value smaller than that is set as the threshold value. Good.

  If the condition of step S5 is not satisfied, the ECU 80 proceeds to step S6, closes the first control valve 101 and opens the second control valve 102. In this case, the GTL fuel discharged from the first fuel pump 21 is stored only in the first common rail 23. Thereafter, the ECU 80 proceeds to step S7 and executes fuel-specific injection. That is, the ECU 80 supplies the first solenoid coil 48 with an excitation current corresponding to the injection amount and the number of injections of the GTL fuel in accordance with the timing at which the injection of the GTL fuel is to be started. In accordance with the timing at which the injection of the oil is to be started, an excitation current corresponding to the light oil injection amount and the number of injections is supplied from the second coil drive circuit 84 to the second solenoid coil 68, so that the GTL Fuel is injected from the second nozzle holes 40 respectively. However, when the injection ratio of the GTL fuel is 100%, the second solenoid coil 68 is not excited and only the injection of the GTL fuel from the first injection hole 39 is executed. If there is an operation region in which the light oil injection ratio is set to 100%, the first solenoid coil 48 may not be excited in that region, and only light oil injection from the second injection hole 40 may be executed. .

  On the other hand, when the condition of step S5 is satisfied, the ECU 80 proceeds to step S8, opens the first control valve 101, and closes the second control valve 102. In this case, the GTL fuel discharged from the first fuel pump 21 is stored in both the first common rail 23 and the second common rail 24. In addition, when the 2nd control valve 102 is closed in step S8, you may stop the driving | operation of the 2nd fuel pump 22 for light oil synchronizing with this. In this case, the ECU 80 functions as a boost stop means. Thereby, consumption of energy required for pressure | voltage rise of light oil can be reduced, and the fuel consumption rate of the engine 1 can be improved. Thereafter, the ECU 80 proceeds to step S9, and in accordance with the timing at which the injection of GTL fuel should be started, both the first solenoid coil 48 and the second solenoid coil 68 are excited according to the injection amount and the number of injections of GTL fuel. Supply current. As a result, GTL fuel is injected from both the first nozzle hole 39 and the second nozzle hole 40. By performing such a process, the operation region in which the injection ratio of GTL fuel is set to 100% in the high load and high rotation region and the required injection amount of GTL fuel exceeds the maximum injectable amount of the first injection hole 39. , The required amount of GTL fuel is reliably injected from both the first nozzle hole 39 and the second nozzle hole 40. After executing fuel injection in step S7 or step S9, the ECU 80 ends the current routine and starts the routine of FIG. 12 again prior to the next fuel injection timing.

  In the above embodiment, light oil remains in the second common rail 24 immediately after the first control valve 101 is switched to the open state and the second control valve 102 is switched to the closed state. Diesel oil is mixed in the fuel to be used. However, once the condition of step S5 is satisfied, it is usual that the condition of step S5 is continuously satisfied thereafter for a period sufficiently longer than the fuel injection cycle. Therefore, if the fuel injection in step S9 is executed once or twice, only the GTL fuel can be reliably injected from both the injection holes 39 and 40 thereafter, and there is no problem in practical use. Immediately after switching the first control valve 101 to the closed state and the second control valve 102 to the open state, GTL fuel remains in the second common rail 24 and the light oil injection ratio is substantially reduced. However, there is no particular problem for the same reason as described above. Further, as a result of the temporary introduction of the GTL fuel into the second common rail 24, the GTL fuel may be mixed into the light oil in the second storage chamber 16, but this does not clearly deteriorate the fuel properties. This also causes no practical problem.

[Third embodiment]
FIG. 13 shows a third embodiment in which the fuel injection device according to the present invention is applied to an engine. In FIG. 13, the same reference numerals are given to portions common to FIG. 1, and the following description will focus on the differences. In the fuel injection device 20B of the present embodiment, in order to ensure the injection amount when the GTL fuel injection ratio is set to 100% as in the fuel injection device 20A of the second embodiment described above, Although a part of the fuel injection device 20 of the first form has been changed so that GTL fuel can be injected from 40, the means for realizing the function is different from that of the second form. That is, in the fuel injection device 20B of this embodiment, a fuel injection valve 25A is used instead of the fuel injection valve 25 of FIG. 1, and a third coil drive circuit 85 for driving the fuel injection valve 25A is added. This is different from the fuel injection device 20 of the first embodiment. Similar to the first and second coil drive circuits 83 and 84, one third coil drive circuit 85 is provided for each fuel injection valve 25A.

  FIG. 14 is a cross-sectional view of a fuel injection valve 25A used in the fuel injection device 20B of the present embodiment. However, in FIG. 14, the same reference numerals are given to the portions common to FIG. The fuel injection valve 25A is provided with a guide wall 38A instead of the partition wall 38 of FIG. 2, and a movable partition wall 110 that partitions the first valve chamber 36 and the second valve chamber 37 is provided on the inner peripheral side of the guide wall 38A. ing. The guide wall 38A is different from the partition wall 38 in FIG. 2 in that the guide wall 38A is provided such that a gap 111 is formed between the tip end (lower end) 38c and the valve body 31. The piston flange 32a of the first needle 32 is slidably fitted to the inner peripheral surface 38a of the guide wall 38A, and the second needle 33 is slidably fitted to the outer peripheral surface 38b of the guide wall 38A. The movable partition 110 is slidably fitted to the inner peripheral surface 38a of the guide wall 38A and is movable in the direction of the center line CL of the fuel injection valve 25A. A partition wall return spring 112 is provided at the rear end of the movable partition wall 110, and a third solenoid coil 113 is provided further rearward of the partition wall return spring 112. The third solenoid coil 113 is fixed to the guide wall 38A and held at a fixed position. The third coil drive circuit 85 shown in FIG. 13 switches supply and stop of excitation current from a power source (not shown) to the third solenoid coil 113 in accordance with an instruction from the ECU 80.

  Returning to FIG. 14, when the third solenoid coil 113 is in a non-excited state, the tapered surface 110 a of the tip of the movable partition 110 is pressed against the inner surface of the tip 31 a of the valve body 31 by the spring force of the partition return spring 112. As a result, the first valve chamber 36 and the second valve chamber 37 are partitioned so that fuel cannot flow, and the first high-pressure fuel passage 50 is not closed by the movable partition wall 110, It communicates with the valve chamber 36. On the other hand, as shown in FIG. 15, when the third solenoid coil 113 is energized, the movable partition 110 is moved to the rear end side (upper end side in the figure) of the fuel injection valve 25A against the partition return spring 112. Gravitate. Therefore, the tapered surface 110a at the tip of the movable partition 110 is separated from the tip 31a of the valve body 31, and the first valve chamber 36 and the second valve chamber 37 are opened to each other through the gap 111. As a result, fuel can flow between the valve chambers 36 and 37. In addition, in the state of FIG. 14, the inlet (opening) of the first high-pressure fuel passage 50 to the first valve chamber 36 is closed by the movable partition 110, and the first high-pressure fuel passage 50 to the first valve chamber 36 is closed. The introduction of high-pressure fuel is blocked. A partition wall driving mechanism is realized by the partition wall return spring 112 and the third solenoid coil 113, and a fuel supply switching unit is realized by a combination of the partition wall driving mechanism and the movable partition wall 110.

  In the fuel injection valve 25A of this embodiment, the first high-pressure fuel passage 50 is connected to the second common rail 24 for light oil in order to ensure the required injection amount when the fuel injection ratio of GTL fuel is set to 100%. The second high-pressure fuel passage 70 is connected to the first common rail 23 for GTL fuel. Therefore, the first low-pressure fuel passage 53 is connected to the second storage chamber 16 for light oil via the second return pipe 19, and the second low-pressure fuel passage 73 is connected to the first GTL fuel via the first return pipe 18. Connected to the storage chamber 15.

  FIG. 16 shows a fuel injection control routine that the ECU 80 executes in place of the routine of FIG. However, the same processes as those in FIG. 12 are denoted by the same reference numerals. In the fuel injection control routine of FIG. 16, processes common to the routine of FIG. 12 are performed in steps S1 to S3 and S5. If the condition of step S5 is not satisfied, the ECU 80 proceeds to step S11, sets the third solenoid coil 113 to the non-excited state, and closes the movable partition 110, that is, the first valve chamber 36 and the second valve chamber 37. Hold in a closed position. In this case, high-pressure gas oil stored in the second common rail 24 is introduced into the first valve chamber 36, and high-pressure GTL fuel stored in the first common rail 23 is introduced into the second valve chamber 37. Thereafter, the ECU 80 proceeds to step S7 and executes fuel-specific injection. That is, the ECU 80 supplies the second solenoid coil 68 with an excitation current corresponding to the injection amount and the number of injections of the GTL fuel in accordance with the timing at which the injection of the GTL fuel is to be started. In accordance with the timing at which the injection of the oil is to be started, the exciting current corresponding to the light oil injection amount and the number of injections is supplied from the first coil drive circuit 83 to the first solenoid coil 48, so that the GTL Fuel is injected from the first injection holes 39 respectively. However, when the injection ratio of the GTL fuel is 100%, the first solenoid coil 48 is not excited and only the injection of the GTL fuel from the second injection hole 40 is executed. If there is an operation region in which the light oil injection ratio is set to 100%, the second solenoid coil 68 is not excited in that region, and only light oil injection from the first injection hole 39 is performed. .

  On the other hand, when the condition of step S5 is satisfied, the ECU 80 proceeds to step S12, where the third solenoid coil 113 is excited to open the movable partition 110, that is, between the first valve chamber 36 and the second valve chamber 37. Are held at positions where they communicate with each other through the gap 111. In this case, the first high-pressure fuel passage 50 and the first valve chamber 36 are blocked, and high-pressure GTL fuel from the second high-pressure fuel passage 70 is introduced into both the valve chambers 36 and 37. Thereafter, the ECU 80 proceeds to step S9, and in accordance with the timing at which the injection of GTL fuel should be started, both the first solenoid coil 48 and the second solenoid coil 68 are excited according to the injection amount and the number of injections of GTL fuel. Supply current. As a result, GTL fuel is injected from both the first nozzle hole 39 and the second nozzle hole 40. By performing such a process, the operating region in which the injection ratio of the GTL fuel is set to 100% in the high load high rotation region and the required injection amount of the GTL fuel exceeds the maximum injectable amount of the second injection hole 40. , The required amount of GTL fuel is reliably injected from both the first nozzle hole 39 and the second nozzle hole 40. After executing fuel injection in step S7 or step S9, the ECU 80 ends the current routine and starts the routine of FIG. 12 again prior to the next fuel injection timing.

  In the above embodiment, the light oil remains in the first valve chamber 36 immediately after the position of the movable partition 110 is switched from the closed position to the open position, and the light oil is injected into the fuel injected from the first injection hole 39. Mix. However, as in the case of the second embodiment, if the condition of step S5 is once satisfied, then the condition of step S5 is continuously satisfied over a period sufficiently longer than the fuel injection cycle. It is customary. Therefore, if the fuel injection in step S9 is executed once or twice, only the GTL fuel can be reliably injected from both the injection holes 39 and 40 thereafter, and there is no problem in practical use. Immediately after the movable partition 110 is switched from the open position to the closed position, GTL fuel remains in the first valve chamber 36 and the injection ratio of light oil is substantially reduced. There is no problem. Further, there is no possibility that other fuels are mixed in the fuel return pipes 18 and 19. Furthermore, in this embodiment, the movable partition 110 inside the fuel injection valve 25A is driven to inject GTL fuel from both the nozzle holes 39, 40, and to separate light oil and GTL fuel from the respective nozzle holes 39, 40. Therefore, there is an advantage that the response is excellent as compared with the second embodiment.

  Even when the movable partition 110 is held in the open position in step S12, it is necessary to drive the first needle 32 by introducing pressure into the first command chamber 43b, so that the second fuel pump 22 for light oil is used. It is desirable to keep driving. However, it goes without saying that the second fuel pump 22 may be stopped when the first needle 32 is driven without using the light oil pressure.

[Fourth form]
FIG. 17 shows a fourth embodiment in which the fuel injection device according to the present invention is applied to an engine. In FIG. 17, the same reference numerals are given to portions common to FIG. The fuel injection device 20C of the present embodiment is different from the fuel injection device 20 of the first embodiment in that a flow path switching valve 120 is provided between the first common rail 23 and the second common rail 24 and each fuel injection valve 25. Is different. The flow path switching valve 120 is provided as a fuel supply switching means for switching the connection relationship between the common rails 23 and 24 and the fuel injection valve 25 so that GTL fuel or light oil can be injected from both the nozzle holes 39 and 40. It has been.

  FIG. 18 shows a schematic configuration of the flow path switching valve 120. The flow path switching valve 120 includes a cylindrical valve main body 121, a plunger 122 inserted into the valve main body 121, and a first plunger driving mechanism 123a and a second plunger driving mechanism provided on the left and right sides of the valve main body 121. 123b. A first inflow port 124a and a second inflow port 124b are provided on one side of the valve body 121, and a first outflow port 125a and a second outflow port 125b are provided on the other side. The first inflow port 124a is connected to the first common rail 23, and the first outflow port 125a is connected to the first high pressure fuel passage 50 or the second high pressure fuel passage 70 of the fuel injection valve 25, respectively. On the other hand, the second inflow port 124b is connected to the second common rail 24, and the second outflow port 125b is connected to the second high pressure fuel passage 70 or the first high pressure fuel passage 50 of the fuel injection valve 25, respectively.

  The plunger 122 includes a piston portion 126 and drive shafts 127 a and 127 b provided coaxially on the left and right sides of the piston portion 126. The piston part 126 is fitted inside the valve body 121 so as to be movable in the axial direction (left-right direction) of the valve body 121. Appropriate sealing means (not shown) is provided between the outer periphery of the piston portion 126 and the inner periphery of the valve main body 121, whereby the inside of the valve main body 121 has the first liquid sandwiched between the piston portion 126. It is divided into a chamber 128a and a second liquid chamber 128b. It is impossible for the liquid to flow between the two liquid chambers 128a and 128b.

  The plunger drive mechanisms 123a and 123b, for example, push the drive shafts 127a and 127b toward the axial center by spring force, while using the electromagnetic force of the solenoid coil to pull the drive shafts 127a and 127b outward in the axial direction. Composed. By means of the plunger drive mechanisms 123a and 123b, the plunger 122 is moved to a neutral position Pn indicated by a solid line in the drawing, a first operating position P1 displaced to the left of the neutral position, and a first position displaced to the right of the neutral position. Driven between two operating positions P2. In FIG. 18, the piston 126 at the operation positions P1 and P2 is indicated by an imaginary line. When the plunger 122 is in the neutral position Pn, the first inflow port 124a and the first outflow port 125a open to the first liquid chamber 128a, and the second inflow port 124b and the second outflow port 125b open to the second liquid chamber 128b. To do. In this case, GTL fuel flows into the first liquid chamber 128a from the first inflow port 124a, and light oil flows into the second liquid chamber 128b from the second inflow port 124b. Then, GTL fuel is supplied to the fuel injection valve 25 from the first outflow port 125a, and light oil is supplied to the fuel injection valve 25 from the second outflow port 125b.

  When the plunger 122 is in the first operating position P1, the first liquid chamber 128a expands, the second inflow port 124b is closed by the piston portion 126, and the first inflow port 124a, the first outflow port 125a, and the second outflow port are closed. A port 125b opens into the first liquid chamber 128a. In this case, the GTL fuel that has flowed into the first liquid chamber 128a from the first inflow port 124a is supplied to the fuel injection valve 25 from both outflow ports 125a and 125b. On the other hand, when the plunger 122 is in the second operating position P2, the second liquid chamber 128b expands, the first inflow port 124a is closed by the piston portion 126, and the second inflow port 124b, the first outflow port 125a, and the second Two outflow ports 125b open to the first liquid chamber 128a. In this case, the light oil that has flowed into the second liquid chamber 128b from the second inflow port 124b is supplied to the fuel injection valve 25 from both the outflow ports 125a and 125b. That is, when the plunger 122 is in the neutral position Pn, the GTL fuel is supplied to one of the first high-pressure fuel passage 50 and the second high-pressure fuel passage 70 of the fuel injection valve 25 and the other high-pressure fuel passage is provided. When the plunger 122 is in the first operating position P1, GTL fuel is supplied to both high pressure fuel passages, and when the plunger 122 is in the second operating position P2, light oil is supplied to both high pressure fuel passages. The The fuel injection valve 25 is the same as in the first embodiment. The correspondence relationship between the first high pressure fuel passage 50 and the second high pressure fuel passage 70 of the fuel injection valve 25 and the fuel type may be appropriately selected as in the first embodiment. Hereinafter, the description will be continued assuming that the first outflow port 125a is connected to the first high-pressure fuel passage 50 and the second outflow port 125b is connected to the second high-pressure fuel passage 70.

  As shown in FIG. 18, the driving of the plunger 122 by the plunger driving mechanisms 123a and 123b is controlled by the ECU 80. FIG. 19 shows a fuel injection control routine that the ECU 80 executes in place of the routine of FIG. However, the same processes as those in FIG. 12 are denoted by the same reference numerals. In the fuel injection control routine of FIG. 19, processes common to the routine of FIG. 12 are performed in steps S1 to S3 and S5. If the condition in step S5 is not satisfied, the ECU 80 proceeds to step S21, in which only the light oil is injected, that is, the injection ratio of the light oil is 100%, and whether the required injection amount is equal to or greater than a predetermined threshold value. to decide. The threshold value is set to a maximum value of the amount of light oil that can be injected from the second nozzle hole 40 or a small value with some allowance. When the second outflow port 125b is connected to the first high-pressure fuel passage 50, the maximum amount of light oil that can be injected from the first injection hole 39 or a value smaller than that may be set as the threshold value. In this case, the threshold value may be the same as or different from the threshold value used in step S5.

  When the condition of step S21 is not satisfied, the ECU 80 proceeds to step S22 and controls the plunger drive mechanisms 123a and 123b so that the plunger 122 is held at the neutral position Pn. In this case, as described above, the GTL fuel discharged from the first fuel pump 21 is supplied to the first high-pressure fuel passage 50, and the light oil discharged from the second fuel pump 22 is supplied to the second high-pressure fuel passage 70, respectively. Is done. Thereafter, the ECU 80 proceeds to step S7 and executes fuel-specific injection. That is, the ECU 80 supplies the first solenoid coil 48 with an excitation current corresponding to the injection amount and the number of injections of the GTL fuel in accordance with the timing at which the injection of the GTL fuel is to be started. In accordance with the timing at which the injection of the oil is to be started, an excitation current corresponding to the light oil injection amount and the number of injections is supplied from the second coil drive circuit 84 to the second solenoid coil 68, so that the GTL Fuel is injected from the second nozzle holes 40 respectively. However, when the injection ratio of the GTL fuel is 100%, the second solenoid coil 68 is not excited and only the injection of the GTL fuel from the first injection hole 39 is executed. When the light oil injection ratio is 100%, the first solenoid coil 48 is not excited, and only light oil injection from the second injection hole 40 is executed.

  On the other hand, when the condition of step S5 is satisfied, the ECU 80 proceeds to step S23 and controls the plunger driving mechanisms 123a and 123b so that the plunger 122 is held at the first operating position P1. In this case, the GTL fuel discharged from the first fuel pump 21 is supplied to both the high-pressure fuel passages 50 and 70 of the fuel injection valve 25. When the plunger 122 is held at the first operating position P1 in step S23, the operation of the second fuel pump 22 for light oil is stopped in synchronization with this, thereby causing the ECU 80 to function as a boost stop means. Also good. Thereby, consumption of energy required for pressure | voltage rise of light oil can be reduced, and the fuel consumption rate of the engine 1 can be improved. Thereafter, the ECU 80 proceeds to step S9, and in accordance with the timing at which the injection of GTL fuel should be started, both the first solenoid coil 48 and the second solenoid coil 68 are excited according to the injection amount and the number of injections of GTL fuel. Supply current. As a result, GTL fuel is injected from both the first nozzle hole 39 and the second nozzle hole 40. By performing such a process, the operation region in which the injection ratio of GTL fuel is set to 100% in the high load and high rotation region and the required injection amount of GTL fuel exceeds the maximum injectable amount of the first injection hole 39. , The required amount of GTL fuel is reliably injected from both the first nozzle hole 39 and the second nozzle hole 40.

  When the condition of step S21 is satisfied, the ECU 80 proceeds to step S24 and controls the plunger driving mechanisms 123a and 123b so that the plunger 122 is held at the second operating position P2. In this case, the light oil discharged from the second fuel pump 22 is supplied to both the high-pressure fuel passages 50 and 70 of the fuel injection valve 25. If the plunger 122 is held at the second operating position P2 in step S24, the operation of the first fuel pump 21 for GTL fuel is stopped in synchronism with this, thereby causing the ECU 80 to function as a boost stop means. Also good. Thereby, the consumption of energy required for boosting the GTL fuel can be reduced, and the fuel consumption rate of the engine 1 can be improved. Thereafter, the ECU 80 proceeds to step S25, and in accordance with the timing at which the light oil injection is to be started, both the first solenoid coil 48 and the second solenoid coil 68 are supplied with an excitation current corresponding to the light oil injection amount and the number of injections. Supply. Thereby, light oil is injected from both the first nozzle hole 39 and the second nozzle hole 40. By performing such processing, in the case where the injection ratio of light oil is set to 100% in a high load low rotation region or the like and the required injection amount of light oil exceeds the maximum injectable amount of the second injection hole 40, The required amount of light oil is reliably injected from both the first nozzle hole 39 and the second nozzle hole 40. After executing the fuel injection in step S7, step S9 or S25, the ECU 80 ends the current routine and starts the routine of FIG. 19 again prior to the next fuel injection timing.

  In the above embodiment, light oil remains downstream of the second outflow port 125b immediately after the plunger 122 of the flow path switching valve 120 is switched to the first operation position P1, and immediately after switching to the second operation position P2. The GTL fuel remains downstream of the 1 outflow port 125a. Therefore, immediately after the switching, the injection ratio of GTL fuel or light oil does not strictly become 100%. However, once the condition of step S5 or S21 is once satisfied, it is usual that the same condition is subsequently satisfied continuously for a period sufficiently longer than the fuel injection cycle. Therefore, if the fuel injection in step S9 or S25 is executed once or twice, only GTL fuel or light oil can be reliably injected from both the injection holes 39 and 40 thereafter, and this causes a problem in practice. Absent. Further, as a result of the same fuel being temporarily introduced into both the high-pressure fuel passages 50 and 70 of the fuel injection valve 25, GTL fuel is mixed into the light oil in the second storage chamber 16 or the GTL fuel in the first storage chamber 15. Although light oil may be mixed in, the fuel properties are not clearly deteriorated by this, and this also causes no practical problem.

[Fifth embodiment]
FIG. 20 shows a fifth embodiment in which the fuel injection device according to the present invention is applied to an engine. In FIG. 20, parts that are the same as those in FIG. 1 are given the same reference numerals, and differences will be mainly described below. In the fuel injection device 20D of the present embodiment, the second common rail 24 for light oil is omitted from the fuel injection device 20 of FIG. 1, a low-pressure feed pump 22A is provided instead of the second fuel pump 22 for light oil, and It differs from the fuel injection device 20 of the first embodiment in that a pressure increasing mechanism 130 is provided between the first common rail 23 and the feed pump 22A and the fuel injection valve 25. The feed pump 22 </ b> A pumps the light oil stored in the second storage chamber 16 through the segmenter 17 and sends it to the pressure increasing mechanism 130. The discharge pressure of the feed pump 22A is lower than that of the first fuel pump 21. For example, while the discharge pressure of the first fuel pump 21 is about 100 MPa or higher, the discharge pressure of the feed pump 22A is about 0.5 MPa.

  FIG. 21 shows the configuration of the pressure increasing mechanism 130. The pressure increasing mechanism 130 increases the pressure of the light oil sent from the feed pump 22A using the pressure of the GTL fuel supplied from the first common rail 23. In order to realize the pressure increasing function, the pressure increasing mechanism 130 includes a pressure increasing cylinder 131, a pressure increasing piston 132 slidably accommodated in the pressure increasing cylinder 131, a three-way valve 133, and an electromagnetically driven control. And a valve 134. The pressure-increasing piston 132 includes a first piston part 132a, a second piston part 132b that is coaxially arranged on one end side of the first piston part 132a and has a diameter slightly smaller than that of the first piston part 132a, and a first piston The pressure plunger 132c arrange | positioned coaxially at the other end side of the part 132a is provided. The pressure increasing cylinder 131 is divided into a first pressure chamber 131a, a second pressure chamber 131b, and a third pressure chamber 131c by piston portions 132a and 132b of the pressure increasing piston 132. Further, a pressure increasing chamber 131d is connected to the first pressure chamber 131a, and a pressure plunger 132c is fitted into the pressure increasing chamber 131d. The inner diameter of the pressure increasing chamber 131d is sufficiently smaller than that of the second pressure chamber 131b. Therefore, the area of the pressurizing plunger 132c is sufficiently smaller than the area of the piston portion 132a of the pressure increasing piston 132.

  Inside the three-way valve 133, a piston 133a is slidably provided. A first pressure chamber 133b and a second pressure chamber 133c are provided on both sides of the piston 133a. The second pressure chamber 133c communicates with the third pressure chamber 133e via the intermediate path 133d. The second pressure chamber 133c is provided with a first valve body 133f, and the third pressure chamber 133e is provided with a second valve body 133g. The valve bodies 133f and 133g are coaxially connected to each other by a valve shaft 133h that passes through the intermediate path 133d. When these valve bodies 133f and 133g are displaced upward, the second valve body 133g closes the space between the third pressure chamber 133e and the intermediate passage 133d, and the space between the second pressure chamber 133c and the intermediate passage 133d. open. When the valve bodies 133f and 133g are displaced downward, the first valve body 133f closes the space between the second pressure chamber 133c and the intermediate passage 133d, and opens the space between the third pressure chamber 133e and the intermediate passage 133d. That is, the intermediate path 133d is selectively connected to either the second pressure chamber 133c or the third pressure chamber 133e according to the positions of the valve bodies 133f and 133g. The diameters of the first valve body 133f and the second valve body 133g are sufficiently smaller than the diameter of the piston 133a. The control valve 134 is a 2-port 2-position switching valve that is opened and closed according to switching between excitation and non-excitation of the solenoid coil 134a.

  The pressure increasing mechanism 130 is provided with a first inflow port 135a, a second inflow port 135b, and a return port 135c. The high pressure GTL fuel stored in the first common rail 23 is supplied to the first inflow port 135a, and the low pressure light oil sent from the feed pump 22A is supplied to the second inflow port 135b. The high-pressure GTL fuel supplied to the first inflow port 135a is guided to the second pressure chamber 131b via the first high-pressure fuel passage 141. The first high-pressure fuel passage 141 is branched halfway, and the branch passage 141 a is connected to one of the first high-pressure fuel passage 50 and the second high-pressure fuel passage 70 of the fuel injection valve 25. On the other hand, the low-pressure gas oil supplied to the second inflow port 135b is guided to the pressure increasing chamber 131d via the check valve 136. The check valve 136 is provided in a direction that can prevent the backflow of light oil from the pressure increasing chamber 131d to the second inflow port 135b. A second high pressure fuel passage 142 is connected to the front end (lower end in the figure) of the pressure increasing chamber 131 d, and the second high pressure fuel passage 142 is connected to the first high pressure fuel passage 50 or the second high pressure fuel passage 70 of the fuel injection valve 25. Connected to one of the other passages. The second high pressure fuel passage 142 may be provided with a check valve that prevents the backflow of light oil to the pressure increasing chamber 131d.

  The GTL fuel supplied to the second pressure chamber 131b of the pressure increasing cylinder 131 is guided to the first pressure chamber 133b of the three-way valve 133 while being depressurized by the first orifice 137. The GTL fuel supplied to the first pressure chamber 133b is further decompressed by the second orifice 138 and guided to the inflow side of the control valve 134. The inner diameter of the second orifice 138 is smaller than that of the first orifice 137. The outflow side of the control valve 134 is connected to the return port 135 c through the low pressure return passage 143. The second pressure chamber 133c of the three-way valve 133 and the third pressure chamber 131c of the pressure increasing cylinder 131 are also connected to the return port 135c via the low pressure return passage 143, respectively. Further, the third pressure chamber 133e of the three-way valve 133 is connected to the second pressure chamber 131b of the pressure-increasing cylinder 131 via the pressure introduction path 144, and the intermediate path 133d of the three-way valve 133 is connected to the pressure-increasing cylinder via the communication path 145. 131 is connected to the first pressure chamber 131a.

  The pressure increasing mechanism 130 configured as described above operates as follows by switching the position of the control valve 134. First, when the control valve 134 is closed, the space between the first pressure chamber 131a of the three-way valve 133 and the low pressure return passage 143 is blocked by the control valve 134, so that the first high pressure fuel passage from the first inlet port 135a. 141, the pressure of the GTL fuel guided through the second pressure chamber 131 b of the pressure increasing cylinder 131 and the first orifice 137 is confined in the first pressure chamber 133 a of the three-way valve 133. A downward pushing force acts on the piston 133b of the three-way valve 133 by the pressure. At this time, high-pressure GTL fuel is also introduced from the second pressure chamber 131b of the pressure-increasing cylinder 131 to the third pressure chamber 133e of the three-way valve 133 via the pressure introduction path 144, and this pressure causes the second valve body 133g to enter An upward pushing force acts. However, since the area of the piston 133a is sufficiently larger than that of the second valve body 133g, the force received from the first pressure chamber 133b becomes larger, and the piston 133a moves downward. Accordingly, the first valve body 133f closes between the second pressure chamber 133c and the intermediate passage 133d, and opens between the third pressure chamber 133e and the intermediate passage 133d. As a result, the high-pressure GTL fuel guided to the third pressure chamber 133e is introduced from the intermediate path 133d into the first pressure chamber 131a of the pressure increasing cylinder 131 through the communication path 145. In this case, the pressure of the GTL fuel supplied to the first inflow port 135a acts on both the first pressure chamber 131a and the second pressure chamber 131b, but the area of the first piston portion 132a is that of the second piston portion 132b. Since it is larger than that, the pressure-increasing piston 132 moves upward. As a result, the pressurizing plunger 132c moves backward from the pressure increasing chamber 131d to increase the volume of the pressure increasing chamber 131d, and low pressure light oil is taken into the pressure increasing chamber 131d from the check valve 136. At this time, the GTL fuel in the third pressure chamber 131 c of the pressure increasing cylinder 131 is pushed out to the low pressure return passage 143.

  On the other hand, when the control valve 134 is opened, the first pressure chamber 133 b of the three-way valve 133 is connected to the low pressure return passage 143 through the control valve 134. Thereby, the force which pushes down the piston 133b of the three-way valve 133 falls. Accordingly, the second valve body 133g is pushed upward by the pressure of the GTL fuel introduced into the third pressure chamber 133e of the three-way valve 133, whereby the second valve body 133g is moved between the third pressure chamber 133e and the intermediate passage 133d. Close the gap. In this case, the first valve body 133f also moves upward, and the intermediate passage 134d and the second pressure chamber 134c are opened. As a result, the pressure in the first pressure chamber 131a of the pressure increasing cylinder 131 is released to the low pressure return passage 143 via the communication passage 145, the intermediate passage 133d of the three-way valve 133, and the second pressure chamber 133c. The pressure increasing piston 132 is pushed downward by the pressure of the GTL fuel in the second pressure chamber 131b of the pressure increasing cylinder 131, and the pressure plunger 132c is pushed into the pressure increasing chamber 131d. As a result, the volume of the pressure increasing chamber 131d is reduced, and the light oil inside thereof is compressed. As a result, the pressure of the light oil in the pressure increasing chamber 131 d is increased, and the high pressure light oil is discharged into the second high pressure fuel passage 142. At this time, low pressure GTL fuel is supplied to the third pressure chamber 131c of the pressure increasing cylinder 131 from the low pressure return passage 143.

  When the control valve 134 is closed again after the light oil has been pressurized in the pressure increasing chamber 131d, the pressurizing plunger 132c is retracted again from the pressure increasing chamber 131d and the low pressure light oil is taken into the pressure increasing chamber 131d. Thus, by repeatedly opening and closing the control valve 134, the intake of the light oil into the pressure increasing chamber 131d and the pressure increase of the light oil are repeated, and the high pressure light oil is sent out from the second high pressure fuel passage 142 to the fuel injection valve 25. be able to. Since the GTL fuel introduced into the second pressure chamber 131b of the booster cylinder 131 has a high pressure boosted by the first fuel pump 21, the area of the second piston part 132b of the booster piston 132, By setting the ratio to the area of the pressurizing plunger 132c sufficiently large, the pressure of the light oil discharged from the pressure increasing chamber 131d to the second high pressure fuel passage 142 can be increased to a pressure equal to or higher than that of the GTL fuel. it can. The switching operation of the control valve 134 may be controlled by the ECU 80. In the operation region where the injection ratio of GTL fuel is set to 100%, the switching operation of the control valve 134 may be stopped and the pressure increase of the light oil may be interrupted.

  As described above, according to the pressure increasing mechanism 130 of the present embodiment, the high pressure GTL fuel stored in the first common rail 23 is supplied from the first high pressure fuel passage 141 (specifically, its branch passage 141a) to the pressure increasing chamber. The light oil whose pressure has been increased at 131d can be taken out from the second high-pressure fuel passage 142, respectively. Therefore, either one of the first high-pressure fuel passage 50 or the second high-pressure fuel passage 70 of the fuel injection valve 25 shown in FIGS. 2 and 3 is connected to the first high-pressure fuel passage 141, and the other passage is connected. Is connected to the second high-pressure fuel passage 142, the GTL fuel and the light oil can be respectively injected from the fuel injection valve 25 as in the first embodiment. The internal structure of the fuel injection valve 25 and its operation control may be the same as in the first embodiment.

  FIG. 22 shows a modification of the pressure increase mechanism 130 of this embodiment. In the modified example of FIG. 22, the first recovery groove 146a and the second recovery groove 146b are provided in the axial direction (movement direction) of the pressure increasing piston 132 on the inner periphery of the fitting portion between the pressure increasing cylinder 131 and the pressure plunger 132c. It is provided at intervals. These recovery grooves 146a and 146b are all provided so as to go around the pressure increasing chamber 131d. Further, the positions of these recovery grooves 146a and 146b are set so that they are not always exposed to the pressure increasing chamber 131d from the tip of the pressure plunger 132c in the reciprocating range of the pressure plunger 132c. Further, the first recovery groove 146a is connected to a GTL fuel return line, for example, a low pressure return passage 143, and the second recovery groove 146b is connected to a light oil return line, for example, the second return pipe 19.

  When the first recovery grooves 146a and 146b are provided in this way, the GTL fuel leaking from the first pressure chamber 131a of the pressure increasing cylinder 131 is recovered in the first recovery groove 146a and discharged to the GTL fuel return line. The light oil leaking from the pressure chamber 131d is recovered in the second recovery groove 146b and discharged to the light oil return line. Therefore, the possibility that the GTL fuel and the light oil are mixed inside the pressure increasing cylinder 131 can be reduced or eliminated.

  In FIG. 20, the fuel injection valve 25 and the pressure increase mechanism 130 are depicted as separate components, but the pressure increase mechanism 130 may be provided as a part of the fuel injection valve 25. That is, the pressure increase mechanism 130 may be configured as an internal mechanism of the fuel injection valve 25 by incorporating the pressure increase mechanism 130 inside the fuel injection valve 25. The light oil taken out from the second high pressure fuel passage 142 of the pressure increasing mechanism 130 can be handled in the same manner as the high pressure light oil supplied from the second common rail 24 of FIG. Therefore, the pressure increase mechanism 130 of this embodiment can be combined with the fuel injection valve of the pintle valve type shown in FIG. 7, and can also be combined with the fuel injection valve 25A shown in FIGS. .

  In the present embodiment, the GTL fuel is boosted by the first fuel pump 21 and the light oil is boosted by the pressure-increasing mechanism 130 using the pressure, but a configuration opposite to this may be adopted. That is, the first fuel pump 21 in FIG. 1 is changed to a low-pressure feed pump to eliminate the first common rail 23, the light oil is boosted by the second fuel pump 22 and sent to the second common rail 24, and the second common rail 24 The high pressure light oil is guided from the feed pump to the first inflow port 135a of the pressure increasing mechanism 130, while the low pressure GTL fuel fed from the feed pump is introduced into the second inflow port 135b, and the GTL fuel is supplied using the light oil pressure. The pressure may be increased.

  In addition, when comparing GTL fuel and light oil, GTL fuel has a higher suppression effect of soot, in other words, light oil is more likely to generate soot. Therefore, in order to suppress the occurrence of soot due to light oil, it is desirable to set the injection pressure of light oil higher than that of GTL fuel. On the other hand, the pressure of the fuel obtained in the pressure increasing chamber 131d of the pressure increasing mechanism 130 is sufficiently smaller than the area of the second piston portion 132b of the pressure increasing piston 132. The pressure of the fuel can be increased in the pressure increasing chamber 131d to a pressure higher than the pressure of the fuel introduced into the second pressure chamber 131b. As described above, when there is a difference in the appropriate pressure (appropriate injection pressure) between the two types of fuel, the first fuel (GTL fuel in the above example) having a low appropriate pressure is supplied to the first inflow port 135a. The second fuel (light oil in the above example) with a high proper pressure is introduced into the second inflow port 135b to boost the second fuel to the proper pressure and improve the engine performance, fuel consumption rate, and emissions. can do. On the other hand, components such as a fuel pump for boosting the first fuel, a high-pressure pipe to which the boosted first fuel is guided, or a common rail need only be designed according to the appropriate pressure of the first fuel, The cost, weight, and size of these components can be reduced.

[Sixth embodiment]
FIG. 23 shows a sixth embodiment in which the fuel injection device according to the present invention is applied to an engine. In this embodiment, a part of the fifth embodiment is changed. Therefore, in FIG. 23, the same reference numerals are given to portions common to FIG. 20, and the following description will focus on the differences. In the fuel injection device 20E of the present embodiment, the low-pressure light oil delivered from the feed pump 22A is guided to the pressure-increasing mechanism 150 shared by all the fuel injection valves 25, and the light oil is pressurized by the pressure-increasing mechanism 150. It is different from the fuel injection device 20D of the fifth embodiment in that it is distributed to each fuel injection valve 25.

  FIG. 24 shows the configuration of the pressure increasing mechanism 150. The pressure-increasing mechanism 150 includes a pressure-increasing cylinder 151, a pressure-increasing piston 152 slidably accommodated in the pressure-increasing cylinder 151, a first three-way valve 153 for switching the operating direction of the pressure-increasing piston 152, The second three-way valve 154, the electromagnetically driven first control valve 155 and the second control valve 156 for switching the three-way valves 153 and 154, and the collecting pipe to which the light oil pressurized by the pressure-increasing cylinder 151 is guided 157.

  The pressure-increasing piston 152 has a piston part 152a fitted into the pressure-increasing cylinder 151 so as to divide the inside of the pressure-increasing cylinder 151 into a first pressure chamber 151a and a second pressure chamber 151b, and is coaxial with both ends of the piston part 152a. The first pressurizing plunger 152b and the second pressurizing plunger 152c are provided. A first pressure increasing chamber 151c and a second pressure increasing chamber 151d are provided at both ends of the pressure increasing cylinder 151, and pressurizing plungers 152b and 152c are slidably fitted in these pressure increasing chambers 151c and 151d. The inner diameters of the pressure increasing chambers 151c and 151d are sufficiently smaller than the inner diameters of the pressure chambers 151a and 151b.

  The three-way valves 153 and 154 have the same configuration, and pistons 153a and 154a are slidably provided therein. First pressure chambers 153b and 154b and second pressure chambers 153c and 154c are provided on both sides of the pistons 153a and 154a. The second pressure chambers 153c and 154c communicate with the third pressure chambers 153e and 154e via intermediate paths 153d and 154d, respectively. First valve bodies 153f and 154f are provided in the second pressure chambers 153c and 154, and second valve bodies 153g and 154g are provided in the third pressure chambers 153e and 154e, respectively. The valve bodies 153f and 153g of the first three-way valve 153 are coaxially connected to each other by a valve shaft 153h that passes through the intermediate passage 153d, and the valve bodies 154f and 154g of the second three-way valve 154 are connected by a valve shaft 154h that passes through the intermediate passage 154d. They are connected to each other coaxially. The diameters of the first valve bodies 153f and 154f and the second valve bodies 153g and 154g are sufficiently smaller than the diameters of the pistons 153a and 154a. The first control valve 155 and the second control valve 156 are two-port two-position switching valves that are opened and closed in accordance with switching between excitation and non-excitation of the solenoid coils 155a and 156a, respectively.

  The pressure increasing mechanism 150 is provided with a first inflow port 160a, a second inflow port 160b, and a pair of return ports 160c. The high pressure GTL fuel stored in the first common rail 23 is supplied to the first inflow port 160a, and the low pressure light oil sent from the feed pump 22A is supplied to the second inflow port 160b. The high-pressure GTL fuel supplied to the first inflow port 160a is guided from the first high-pressure fuel passage 161 to the third pressure chambers 153e and 154e of the three-way valves 153 and 154 and also to the first orifice 162 or the second orifice 163. The pressure is reduced and the gas is also guided to the first pressure chambers 153b and 154b of the three-way valves 153 and 154. The GTL fuel supplied to the first pressure chambers 153b and 154b is further depressurized by the third orifice 164 or the fourth orifice 165 and guided to the inflow side of the first control valve 155 or the second control valve 156. The first orifice 162 and the second orifice 163 are equal to each other, the third orifice 164 and the fourth orifice 165 are equal to each other, and their inner diameters are smaller than the inner diameters of the first orifice 162 and the second orifice 163.

  Outflow sides of the control valves 155 and 156 are connected to a return port 160 c via a low pressure return passage 166. The second pressure chambers 153c and 154c of the three-way valves 153 and 154 are also connected to the return port 160c through the low pressure return passage 166. Further, the intermediate path 153 d of the first three-way valve 153 is connected to the first pressure chamber 151 a of the pressure-increasing cylinder 151 via the communication path 167, and the intermediate path 154 d of the second three-way valve 154 is connected to the pressure-increasing cylinder 151 via the communication path 168. Are connected to the second pressure chamber 151b.

  On the other hand, the low-pressure light oil supplied to the second inflow port 160b is guided to the pressure increasing chambers 151c and 151d via the first check valve 171 or the 2172th. The first check valve 171 and the second check valve 172 are provided in such a direction as to prevent the light oil from flowing out from the pressure increasing chambers 151c and 151d. The pressure increasing chambers 151c and 151d are connected to the collecting pipe 157 via the third check valve 173 and the fourth check valve 174, respectively. These check valves 173 and 174 are provided in a direction that prevents the backflow of light oil from the collecting pipe 157 to the pressure increasing chambers 151c and 151d. A distribution pipe 175 for supplying light oil to each fuel injection valve 25 is connected to the collecting pipe 157. The distribution pipe 175 has a second high-pressure fuel passage 70 (see FIG. 2) when light oil is injected from the second injection hole 40 of the fuel injection valve 25 and a first oil injection when light oil is injected from the first injection hole 39. 1 It is connected to the high pressure fuel passage 50. As is clear from FIG. 23, high-pressure GTL fuel is supplied from the first common rail 23 to each fuel injection valve 25, and there is no GTL fuel supply path from the pressure increase mechanism 150 to the fuel injection valve 25. The GTL fuel is supplied to the first inflow port 160a of the pressure increasing mechanism 150 through a pipe line different from the pipe line for supplying the GTL fuel from the first common rail 23 to the fuel injection valve 25. The return port 160 c of the pressure increasing mechanism 150 is connected to a first return pipe 18 that connects each fuel injection valve 25 and the first storage chamber 15.

  The pressure increasing mechanism 150 configured as described above operates as follows by switching the positions of the control valves 155 and 156. First, a case where the first control valve 155 is closed and the second control valve 156 is opened will be described. In this case, paying attention to the first three-way valve 153, the first pressure chamber 153b is blocked by the first control valve 155, so that the first orifice 162 is provided in the first pressure chamber 153b. The pressure of the GTL fuel that has passed through is confined, and a downward pushing force acts on the piston 153a by the pressure. At this time, high-pressure GTL fuel is also introduced into the third pressure chamber 153e, and an upward pushing force acts on the second valve body 153g by the pressure. However, since the area of the piston 153a is sufficiently larger than that of the second valve body 153g, the force received from the first pressure chamber 153b becomes larger, and the piston 153a moves downward. Accordingly, the first valve body 153f closes the space between the second pressure chamber 153c and the intermediate path 153d. In this case, the second valve body 153g also moves downward, and the space between the third pressure chamber 153e and the intermediate path 153d is opened. As a result, the high-pressure GTL fuel guided to the third pressure chamber 153e is introduced from the intermediate passage 153d to the first pressure chamber 151a of the pressure increasing cylinder 151 via the communication passage 167. Regarding the second three-way valve 154, the second control valve 156 is opened and the first pressure chamber 154 b is connected to the low pressure return passage 166, so that the GTL fuel guided to the first pressure chamber 154 b enters the low pressure return passage 166. escape. For this reason, the force which pushes piston 154 downward falls. Therefore, the second valve body 154g is pushed upward by the pressure of the GTL fuel introduced into the third pressure chamber 154e, whereby the second valve body 154g closes between the third pressure chamber 154e and the intermediate path 154d. . In this case, the first valve body 154f also moves upward, and the intermediate passage 154d and the second pressure chamber 154c are opened. As a result, the pressure in the first pressure chamber 151a of the pressure-increasing cylinder 151 is released to the low pressure return passage 166 via the communication path 168, the intermediate path 154d, and the second pressure chamber 154c. As a result, the pressure-increasing cylinder 151 is driven rightward in FIG. 24, and the pressure plunger 152b is retracted from the first pressure-increasing chamber 151c, while the pressure plunger 152c is pushed into the second pressure-increasing chamber 151d. Therefore, the volume of the first pressure increasing chamber 151c is increased and low pressure light oil is taken into the first pressure increasing chamber 151c from the first check valve 171 while the volume of the second pressure increasing chamber 151d is reduced. The light oil inside is compressed. As a result, the pressure of the light oil in the second pressure increasing chamber 151 d is increased, and the high pressure light oil is discharged from the fourth check valve 174 to the collecting pipe 157.

  When the first control valve 155 is opened and the second control valve 156 is closed from the above state, the operations of the first three-way valve 153 and the second three-way valve 154 are reversed, and the first pressure of the pressure increasing cylinder 151 is increased. The pressure in the chamber 151a is released to the low pressure return passage 166 through the communication path 167, the intermediate path 153d and the second pressure chamber 153c, while the high pressure led to the third pressure chamber 154e of the second three-way valve 154. The GTL fuel is introduced into the second pressure chamber 151b of the pressure-increasing cylinder 151 from the intermediate path 154d through the communication path 168. As a result, the pressure increasing cylinder 151 is driven to the left in FIG. 24, and the pressure plunger 152c is retracted from the second pressure increasing chamber 151d, while the pressure plunger 152b is pushed into the first pressure increasing chamber 151c. Therefore, the volume of the second pressure increasing chamber 151d is increased and low pressure light oil is taken into the second pressure increasing chamber 151d from the second check valve 172, while the volume of the first pressure increasing chamber 151c is reduced. The light oil inside is compressed. As a result, the pressure of the light oil in the first pressure increasing chamber 151 c is increased, and the high pressure light oil is discharged from the third check valve 173 to the collecting pipe 157.

  As described above, according to the pressure increasing mechanism 150 of the present embodiment, the first control valve 155 and the second control valve 156 are alternately reversed to open and close to the collecting pipe 157 from the pressure increasing chambers 151c and 151d. Light oil can be fed. The switching operation of the control valves 155 and 156 may be controlled by the ECU 80. For example, the ECU 80 is controlled to supply high pressure light oil from the collecting pipe 157 to the fuel injection valve 25 in accordance with each fuel injection by switching the control valves 155 and 156 to open and close in synchronization with the fuel injection cycle. May be executed. In the operation region where the injection ratio of GTL fuel is set to 100%, the switching operation of the control valves 155 and 156 may be stopped and the pressure increase of the light oil may be interrupted.

  As described above, according to the pressure increasing mechanism 150 of the present embodiment, the light oil can be boosted using the pressure of the GTL fuel stored in the first common rail 23. Therefore, either the first high-pressure fuel passage 50 or the second high-pressure fuel passage 70 of the fuel injection valve 25 shown in FIGS. 2 and 3 is connected to the first common rail 23, and the other passage is separated. By connecting to the pipe 175, GTL fuel and light oil can be injected from the fuel injection valve 25, respectively, as in the first embodiment. The internal structure of the fuel injection valve 25 and its operation control may be the same as in the first embodiment.

  Also in the pressure increasing mechanism 150 of this embodiment, the first recovery groove and the second recovery groove for recovering the GTL fuel and light oil at the fitting portion between the pressure plunger and the pressure increasing chamber as in the example of FIG. May be provided. The pressure increase mechanism 150 of this embodiment can be combined with the fuel injection valve of the pintle valve type shown in FIG. 7, and can also be combined with the fuel injection valve 25A shown in FIGS. In the present embodiment, the GTL fuel is boosted by the first fuel pump 21, and the light oil is boosted by the pressure-increasing mechanism 150 using the pressure, but a configuration opposite to this may be adopted. Also in this embodiment, since the areas of the pressure plungers 152c and 152d are sufficiently smaller than the area of the piston portion 152a of the pressure increasing piston 152, the pressure increasing chambers 151c and 151d are discharged from the pressure of the fuel driving the pressure increasing piston 152. The fuel pressure can be increased. Therefore, the selection of the fuel to be boosted by the fuel pump and the fuel to be boosted by the pressure increasing mechanism 150 can be considered as in the fifth embodiment.

[Seventh form]
FIG. 25 shows a seventh embodiment in which the fuel injection device according to the present invention is applied to an engine. In FIG. 25, the same reference numerals are given to the portions common to FIG. In the fuel injection device 20F of the present embodiment, a second return pipe 19A for returning low-pressure light oil from the fuel injection valve 25 is connected between the digester 17 and the suction port side of the second fuel pump 22. Thus, a light oil circulation path is formed so as to include the second fuel pump 22, the second common rail 24, the fuel injection valve 25, and the second return pipe 19A. The ECU 80 controls the injection ratio between the GTL fuel and the light oil from the fuel injection valve 25 in accordance with the fuel injection control routine shown in FIG. 5. In particular, when the engine 1 is started at a low temperature, the map shown in FIG. Regardless, the injection ratio of GTL fuel is set to 100%. This is because GTL fuel has a higher cetane number than light oil, and injecting GTL fuel during cold start is advantageous in terms of suppressing white smoke or stabilizing combustion. However, GTL fuel has a higher pour point compared to light oil and may not flow sufficiently at low temperature start. Therefore, in this embodiment, the ECU 80 repeatedly executes the fuel temperature increase control routine shown in FIG. 26 at a predetermined period for the purpose of improving the fluidity of the GTL fuel at the time of low temperature start.

  In the fuel temperature raising control routine of FIG. 26, the ECU 80 first determines in step S31 whether or not the engine 1 is in a cold start state. The determination can be made based on the coolant temperature of the engine 1, for example. In the case of the low temperature start, the ECU 80 proceeds to step S32 and determines whether or not the injection ratio is set so as to inject only the GTL fuel, that is, whether or not the injection ratio of the GTL fuel is set to 100%. When injecting only the GTL fuel, the ECU 80 proceeds to step S33 and executes a micro-circulation control of the light oil. The light oil microcirculation control is a process in which a slight amount of light oil leaks from the high pressure side to the low pressure side of the fuel injection valve 25 within a range in which the light oil is not injected, utilizing a delay in the response of the needle to the excitation of the solenoid coil of the fuel injection valve. is there. For example, when the second injection hole 40 of the fuel injection valve 25 is assigned as the injection hole for light oil, the second solenoid coil 68 of the second drive mechanism 35 corresponding to the second injection hole 40 is used. ) Is repeated for a very short time, so that the light oil leaks from the second command chamber 63b to the second low-pressure fuel passage 73 through the second solenoid chamber 65 within a range where the second needle 33 does not operate. It is executed in step S33. By executing the process of step S33, the ECU 80 functions as a fuel circulation control means. On the other hand, when the condition in step S31 or S32 is denied, the ECU 80 stops the light oil microcirculation control. Then, after the processing of step S33 or S34, the ECU 80 ends the current routine.

  When the above-described micro-circulation control of light oil is executed, the light oil introduced into the second command chamber 63b repeatedly flows out into the second low-pressure fuel passage 73 in small amounts, and the discharged light oil flows from the second return pipe 19A to the second fuel. The pump 22 and the second common rail 24 are returned to the second command chamber 63b. Due to such circulation, the temperature of the light oil is raised, and as a result, the fuel injection valve 25 is heated, and the temperature of the GTL fuel rises early. As a result, it is possible to improve the fluidity of the GTL fuel at the low temperature start.

  When light oil is injected from the first injection hole 39 of the fuel injection valve 25, the first solenoid coil 48 is repeatedly excited in a range where the first needle 32 does not operate in place of the second solenoid coil 68 in step S33. That's fine. This embodiment is not limited to the fuel injection valve 25 of the first embodiment, but can be combined with the fuel injection valve of the pintle valve type shown in FIG. 7 or the fuel injection valve 25A shown in FIGS. Further, the present embodiment may be combined with the fifth or sixth embodiment and this embodiment so that the low-pressure gas oil returned from the low-pressure return passage of the fuel injection valve is guided to the pressure-increasing mechanism.

[Eighth form]
FIG. 27 shows an eighth embodiment in which the fuel injection device according to the present invention is applied to an engine. In FIG. 27, parts common to those in FIG. 1 are denoted by the same reference numerals, and the differences will be mainly described below. In the fuel injection device 20G of the present embodiment, a first return pipe 18A for returning low-pressure GTL fuel from the fuel injection valve 25 is connected between the cementer 17 and the suction port of the first fuel pump 21. Thus, a GTL fuel circulation path is formed so as to include the first fuel pump 21, the first common rail 23, the fuel injection valve 25, and the first return pipe 18A. The ECU 80 controls the injection ratio between the GTL fuel and the light oil from the fuel injection valve 25 in accordance with the fuel injection control routine shown in FIG. 5. In particular, when the engine 1 is started at a low temperature, the map shown in FIG. Regardless, the injection ratio of GTL fuel is set to 100%. The reason is as described in the seventh embodiment. Further, the ECU 80 repeatedly executes the fuel temperature increase control routine shown in FIG. 28 at a predetermined cycle for the purpose of improving the fluidity of the GTL fuel at the time of low temperature start.

  In the fuel temperature raising control routine of FIG. 28, the ECU 80 first determines in step S41 whether or not the engine 1 is in a cold start state. The determination may be the same as step S31 in FIG. In the case of the low temperature start, the ECU 80 proceeds to step S42 and determines whether or not it is a period before the start of the GTL fuel injection. That is, in order to inject GTL fuel, it is necessary to increase the GTL fuel by the first fuel pump 21 and store the GTL fuel at a predetermined pressure in the first common rail 23, and until the preparation is completed, the GTL fuel is injected. Does not start. In step S42, an affirmative determination is made in a period before preparation for injection of the GTL fuel is completed, and a negative determination is made after preparation is completed. If it is determined in step S42 that the injection has not started yet, the ECU 80 proceeds to step S43 and executes a GTL fuel micro-circulation control. The microcirculation control uses a delay in the response of the needle to the excitation of the solenoid coil of the fuel injection valve, and causes a small amount of GTL fuel to leak from the high pressure side to the low pressure side of the fuel injection valve 25 within a range where GTL fuel is not injected. It is. For example, when the first injection hole 39 of the fuel injection valve 25 is assigned as the injection hole for GTL fuel, the first solenoid coil 48 of the first drive mechanism 34 corresponding to the first injection hole 39 is used. ) Is repeated for a very short time to cause GTL fuel to leak from the first command chamber 43b to the first low-pressure fuel passage 53 via the first solenoid chamber 45 within a range in which the first needle 32 does not operate. Is executed in step S43. By executing the processing of step S43, the ECU 80 functions as a fuel circulation control means. On the other hand, when the condition of step S41 or S42 is denied, the ECU 80 stops the GTL fuel microcirculation control. Then, after the processing of step S43 or S44, the ECU 80 ends the current routine.

  When the GTL fuel microcirculation control described above is executed, the GTL fuel introduced into the first command chamber 43b repeatedly flows out into the first low-pressure fuel passage 53 in small amounts, and the outflowed GTL fuel flows from the first return pipe 18A. The first fuel pump 21 and the first common rail 23 are returned to the first command chamber 43b. By such circulation, the temperature of the GTL fuel rises early. As a result, it is possible to improve the fluidity of the GTL fuel at the low temperature start.

  When the GTL fuel is injected from the second injection hole 40 of the fuel injection valve 25, the second solenoid coil 68 is repeatedly excited in a range where the second needle 33 does not operate in place of the first solenoid coil 48 in step S43. do it. This embodiment is not limited to the fuel injection valve 25 of the first embodiment, but can be combined with the fuel injection valve of the pintle valve type shown in FIG. 7 or the fuel injection valve 25A shown in FIGS. Further, the present embodiment may be combined with the fifth or sixth embodiment and this embodiment so that the low-pressure gas oil returned from the low-pressure return passage of the fuel injection valve is guided to the pressure-increasing mechanism. Further, this embodiment may be combined with the seventh embodiment to circulate a trace amount of both GTL fuel and light oil.

  The present invention is not limited to the above-described form and can be carried out in an appropriate form. For example, the first drive mechanism and the second drive mechanism of the fuel injection valve may be appropriately changed as long as the needle can be driven to open and close. The present invention is not limited to an example using GTL fuel and light oil, and can be applied to an appropriate fuel injection device as long as two types of fuel are used. In addition, regarding the control for setting the light oil injection ratio to be large in the high load and low rotation region and setting the GTL fuel injection ratio to be large in the high load and high rotation region, the fuel is injected from a common fuel injection valve. Not limited to this, the present invention may be applied to a configuration in which GTL fuel and light oil are injected from different fuel injection valves.

The figure which shows the structure of the fuel-injection apparatus which concerns on the 1st form of this invention. Sectional drawing in the valve closing state of a fuel injection valve. Sectional drawing in the valve opening state of a fuel injection valve. The figure which shows the map which matched the injection ratio of GTL fuel and light oil, the rotation speed, and the engine load. The flowchart which shows the fuel-injection control routine which ECU of FIG. 1 performs. The figure which shows the relationship between the centerline of the nozzle hole of a fuel injection valve, and a piston combustion chamber. The fragmentary sectional view of the fuel injection valve in the modification which changed the 1st needle of the fuel injection valve into the pintle valve form. The perspective view of a common common rail. The figure which shows the structure of the fuel-injection apparatus which concerns on the 2nd form of this invention. The figure which shows the structure from the fuel pump of FIG. 9 to a fuel injection valve. Sectional drawing in an example of the 1st control valve of FIG. The flowchart which shows the fuel-injection control routine which ECU of FIG. 9 performs. The figure which shows the structure of the fuel-injection apparatus which concerns on the 3rd form of this invention. Sectional drawing in the valve closing state of the fuel injection valve of FIG. Sectional drawing when injecting a single fuel from the fuel injection valve of FIG. 14 is a flowchart showing a fuel injection control routine executed by the ECU of FIG. The figure which shows the structure of the fuel-injection apparatus which concerns on the 4th form of this invention. The figure which shows the structure of the flow-path switching valve of FIG. The flowchart which shows the fuel-injection control routine which ECU of FIG. 17 performs. The figure which shows the structure of the fuel-injection apparatus which concerns on the 5th form of this invention. The figure which shows the circuit structure of the pressure increase mechanism of FIG. The figure which shows the modification of FIG. The figure which shows the structure of the fuel-injection apparatus which concerns on the 6th form of this invention. The figure which shows the circuit structure of the pressure increase mechanism of FIG. The figure which shows the structure of the fuel-injection apparatus which concerns on the 7th form of this invention. The flowchart which shows the fuel temperature increase control routine which ECU of FIG. 25 performs. The figure which shows the structure of the fuel-injection apparatus which concerns on the 8th form of this invention. The flowchart which shows the fuel temperature increase control routine which ECU of FIG. 27 performs.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Cylinder 14 Fuel tank 15 1st storage chamber 16 2nd storage chamber 17 Sedimenter 18, 18A 1st return piping 19, 19A 2nd return piping 20, 20A, 20B, 20C, 20D, 20E, 20F, 20G Fuel Injection device 21 First fuel pump 22 Second fuel pump 22A Feed pump 23 First common rail 24 Second common rail 25, 25A Fuel injection valve 26 Piston 26a Piston combustion chamber 27 Tube (common common rail)
27a Tube partition 27b First pressure chamber 27c Second pressure chamber 31 Valve body 31a Tip of valve body 32 First needle 33 Second needle 34 First drive mechanism 35 Second drive mechanism 36 First valve chamber 37 Second valve Chamber 38 Fuel injection valve partition 39 First injection hole 40 Second injection hole 80 Engine control unit (injection ratio determination means, injection control means, on-off valve control means, boost stop means, fuel circulation control means)
100 Bypass fuel passage (fuel supply switching means)
101 1st control valve (fuel supply switching means, 1st on-off valve)
102 Second control valve (fuel supply switching means, second on-off valve)
110 Movable partition (fuel supply switching means)
112 Bulkhead return spring (fuel supply switching means, bulkhead drive mechanism)
113 third solenoid coil (fuel supply switching means, partition wall drive mechanism)
120 Channel switching valve (fuel supply switching means)
DESCRIPTION OF SYMBOLS 130 Pressure increase mechanism 131d Pressure increase chamber 132 Pressure increase piston 132c Pressure plunger 150 Pressure increase mechanism 152 Pressure increase piston 152a Piston part 152b, 152c Pressure plunger A Cylinder head lower surface CL Center line of fuel injection valve La First injection hole Center line Lb Center line of the second injection hole P1 First operation position P2 Operation position Pa First injection hole center Pb Second injection hole center Pn Neutral position Za High load low rotation region

Claims (3)

A fuel injection device for an internal combustion engine that injects different first fuel and second fuel into a cylinder from a common fuel injection valve,
The fuel injection valve is
A first valve chamber is provided on the center side, a second valve chamber partitioned by a partition wall from the first valve chamber is provided on the outer peripheral side, and a first injection hole communicating with the first valve chamber is provided at the tip portion. And a valve body provided with a second nozzle hole communicating with the second valve chamber,
A first valve body disposed in the first valve chamber so as to open and close the first nozzle hole;
A second valve body disposed in the second valve chamber so as to open and close the second nozzle hole;
A first drive mechanism for opening and closing the first valve body;
A second drive mechanism that opens and closes the second valve body independently of driving the first valve body by the first drive mechanism,
The first fuel is led to one of the first valve chamber and the second valve chamber, and the second fuel is led to the other valve chamber, respectively.
A first state in which the first fuel and the second fuel are led separately into the first valve chamber and the second valve chamber, and the first fuel or the second fuel, Fuel supply switching means for switching between a second state in which any one of the fuels is led to both the first valve chamber and the second valve chamber;
The partition of the fuel injection valve opens between a closed position that partitions the first valve chamber and the second valve chamber, and between the first valve chamber and the second valve chamber; and It functions as a part of the fuel supply means by being configured as a movable partition wall that is movable between an open position for closing the fuel inlet to the valve chamber, and the fuel supply switching means includes the movable partition wall A partition wall drive mechanism is provided for driving the closed position and the open position.
The fuel injection system of the internal combustion engine you wherein a. A fuel injection device for an internal combustion engine that injects different first fuel and second fuel into a cylinder from a common fuel injection valve,
The fuel injection valve is
A first valve chamber is provided on the center side, a second valve chamber partitioned by a partition wall from the first valve chamber is provided on the outer peripheral side, and a first injection hole communicating with the first valve chamber is provided at the tip portion. And a valve body provided with a second nozzle hole communicating with the second valve chamber,
A first valve body disposed in the first valve chamber so as to open and close the first nozzle hole;
A second valve body disposed in the second valve chamber so as to open and close the second nozzle hole;
A first drive mechanism for opening and closing the first valve body;
A second drive mechanism that opens and closes the second valve body independently of driving the first valve body by the first drive mechanism,
The first fuel is led to one of the first valve chamber and the second valve chamber, and the second fuel is led to the other valve chamber, respectively.
A first state in which the first fuel and the second fuel are led separately into the first valve chamber and the second valve chamber, and the first fuel or the second fuel, Fuel supply switching means for switching between a second state in which any one of the fuels is led to both the first valve chamber and the second valve chamber; first pressure boosting means for boosting the first fuel; A second pressurizing means for boosting the fuel of the fuel ,
The fuel supply switching means includes a neutral position in which fuel boosted by each of the first boosting means and the second boosting means is separated from each other and led to the first valve chamber and the second valve chamber; Fuel boosted by the booster of either the booster or the second booster is guided to both the first valve chamber and the second valve chamber, while the fuel boosted by the other booster A flow path switching valve that can be switched between an operation position that prevents passage of
The fuel injection system of the internal combustion engine you wherein a. A first valve chamber is provided on the center side, a second valve chamber partitioned by a partition wall from the first valve chamber is provided on the outer peripheral side, and a first injection hole communicating with the first valve chamber is provided at the tip portion. And a valve body provided with a second nozzle hole communicating with the second valve chamber,
A first valve body disposed in the first valve chamber so as to open and close the first nozzle hole;
A second valve body disposed in the second valve chamber so as to open and close the second nozzle hole;
A first drive mechanism for opening and closing the first valve body;
A second drive mechanism that opens and closes the second valve body independently of driving the first valve body by the first drive mechanism,
The partition wall opens between a closed position that partitions the first valve chamber and the second valve chamber, and between the first valve chamber and the second valve chamber, and fuel for one of the valve chambers. The movable partition is configured as a movable partition that is movable between an open position that closes the introduction port, and further includes a partition drive mechanism that drives the movable partition between the closed position and the open position. fuel injection valve of an internal combustion engine that.

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