JP2007239735A - Fuel injection nozzle, fuel injection device and injector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To remove a deposited deposit, by preventing the deposit from depositing on an inner wall and the outer opening peripheral edge of a second nozzle port 26 unopened when an injection quantity is little in ordinary injection control, in a variable nozzle port type nozzle 1. <P>SOLUTION: In this nozzle 1, a first fuel flow passage 16 and a second fuel flow passage 28 always communicate with each other regardless of opening-closing of the first and second nozzle ports 14 and 26. Thus, since fuel is always introduced to the tip side of a second needle 10, energizing force can be always applied in the opening direction to the second needle 10. Thus, since the second needle 10 can be independently lifted, the fuel is injected from the second nozzle port 26 even when an injection quantity is little, and its deposit is prevented, and the deposit can be removed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention mainly relates to a fuel injection nozzle that is installed in each cylinder of an engine and injects fuel into the cylinder.

[Conventional technology]
Conventionally, a variable injection hole type fuel that can change the number of injection holes to be opened according to the injection amount in order to promote atomization in the low rotation region and high injection rate in the high rotation region. Injection nozzles are known.

  A conventional variable injection hole type fuel injection nozzle includes, for example, a cylindrical first needle, a second needle that is accommodated on the inner peripheral side of the first needle and moves in the same direction as the first needle, The second needle is movably accommodated in the axial direction, and is provided on the inner peripheral side of the first nozzle hole opened and closed by the tip of the first needle and the first nozzle, and by the tip of the second needle And a body provided with a second nozzle hole that is opened and closed.

  Furthermore, a back pressure chamber is formed on the rear end side of the first and second needles, into which high-pressure fuel that biases the first and second needles in the closing direction flows (hereinafter referred to as back pressure chambers). The pressure that the fuel exerts on the first and second needles in the closing direction is called back pressure). Further, high-pressure fuel is also guided to the distal end side of the first needle, and urges the first needle in the opening direction.

  Here, with respect to the first needle, the opening direction is a direction in which the first nozzle hole is opened, and the closing direction is a direction in which the first nozzle hole is closed. In the second needle, the opening direction is a direction in which the second nozzle hole is opened, and the closing direction is a direction in which the second nozzle hole is closed.

  When the fuel flows out from the back pressure chamber and the back pressure decreases, the urging force by the fuel on the tip side of the first needle becomes stronger than the urging force acting in the closing direction such as the back pressure. Is lifted in the opening direction, and the first nozzle hole is opened. As a result of the lift of the first needle, the fuel is also guided to the distal end side of the second needle, and the second needle is biased in the opening direction by the fuel guided to the distal end side of the second needle. When the back pressure is further reduced, the second needle is also lifted in the opening direction, and the second nozzle hole is opened.

  With the above configuration, the conventional variable injection hole type fuel injection nozzle realizes atomization by opening only the first injection hole when the injection amount is small, and first and first when the injection amount is large. Both injection holes are opened to achieve a high injection rate (see, for example, Patent Document 1).

[Problems with conventional technology]
However, according to the conventional variable injection hole type fuel injection nozzle, the second injection hole is not opened unless the first needle is lifted and the fuel is guided to the tip side of the second needle. For this reason, for example, when an operation state with a small injection amount continues and fuel is injected only from the first injection hole as in idle operation, deposits accumulate on the inner wall of the second injection hole and the peripheral edge of the external opening. .
International Publication No. 03/069511 Pamphlet

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a second injection that is not opened when the injection amount is small in a variable injection hole type fuel injection nozzle according to normal injection control. The purpose is to prevent deposits from being deposited on the inner wall of the hole or the periphery of the outer opening, or to remove the deposited deposits.

[Means of Claim 1]
The fuel injection nozzle according to claim 1 is a cylindrical first needle, a second needle that is accommodated on the inner peripheral side of the first needle and moves in the same direction as the first needle, a first needle, and a second needle. The needle is movably accommodated in the axial direction, and is provided on the inner peripheral side of the first nozzle hole that is opened and closed by the tip portion of the first needle and the first nozzle hole, and is opened and closed by the tip portion of the second needle. And a body provided with a second nozzle hole. And in this fuel injection nozzle, the 1st fuel flow path which guides fuel to the tip side of the 1st needle and the 2nd needle are urged in the opening direction so that the 1st needle is urged in the opening direction As described above, the second fuel flow path for guiding the fuel to the distal end side of the second needle is formed, and the first fuel flow path and the second fuel flow path are always in communication.

  As a result, even when the first needle does not lift, fuel having substantially the same pressure as the fuel guided to the distal end side of the first needle is always guided to the distal end side of the second needle. For this reason, as with the first needle, the urging force can always be exerted on the second needle in the opening direction. Therefore, even when the required injection amount is small, the second needle is lifted and the second needle is lifted. Fuel can be injected from the two nozzle holes. As a result, it is possible to prevent deposits from being deposited on the inner wall of the second nozzle hole or the peripheral edge of the outer opening, or to remove the deposited deposits.

  Note that “always” in “the first fuel flow path and the second fuel flow path are always in communication” means that only the first nozzle hole is opened or only the second nozzle hole is opened. In addition to the case, the first fuel channel and the second fuel channel may be used when both the first and second nozzle holes are open or when both the first and second nozzle holes are closed. That is, that is, the first fuel flow path and the second fuel flow path are communicated regardless of whether the first and second nozzle holes are opened or closed by the first and second needles. means.

[Means of claim 2]
According to the fuel injection nozzle of claim 2, the first back pressure chamber into and out of which the fuel for energizing the first needle in the closing direction flows in and out of the first back pressure chamber, and the second needle is A second back pressure chamber into which fuel energizing in the closing direction flows in and out is formed.
Accordingly, the second needle can be lifted independently by operating the fuel pressure (second back pressure) in the second back pressure chamber. For this reason, even when the required injection amount is small, the fuel can be injected from the second injection hole by operating the second back pressure.

[Means of claim 3]
According to the fuel injection nozzle of the third aspect, the back pressure chamber into which the fuel for energizing the first needle and the second needle in the closing direction flows in and out, and the back pressure chamber are formed separately. An intermediate chamber into which fuel energized in the closing direction or the opening direction flows is formed.

  Accordingly, the second needle can individually receive the pressure of the fuel in the back pressure chamber (back pressure) and the pressure of the fuel in the intermediate chamber (intermediate pressure). Therefore, even if only the intermediate pressure is reduced or increased, the second needle does not lift, and when the back pressure is further reduced, the second needle is lifted before the first needle. Design conditions such as area and pressure receiving area of intermediate pressure can be determined.

  As a result, fuel can be injected from the second injection hole even when the required injection amount is small. Furthermore, since the intermediate pressure operating mechanism for increasing / decreasing the intermediate pressure can be made common to all the fuel injection nozzles, the number of mechanisms for operating the fuel pressure inside the fuel injection nozzle can be reduced.

[Means of claim 4]
According to the fuel injection nozzle of the fourth aspect, the first needle is provided on the first main body portion that opens and closes the first injection hole and the rear end side of the first main body portion, and the hollow on the inner peripheral side is the first needle portion. A first rear end portion that is smaller in diameter than one main body portion and is formed so as to penetrate to the rear end side, and the second needle is slidable in the hollow on the inner peripheral side of the first main body portion. A second main body portion that is accommodated and opens and closes the second nozzle hole, and a second rear portion that is provided on the rear end side of the second main body portion and is slidably accommodated in the hollow on the inner peripheral side of the first rear end portion. And an end. The intermediate chamber is formed between the second main body portion and the first rear end portion.

This means shows one form of the means of claim 3.
According to this means, the intermediate pressure acts on the first needle in the opening direction and acts on the second needle in the closing direction. For this reason, if the intermediate pressure is reduced, the first needle becomes difficult to lift and the second needle becomes easy to lift. Therefore, according to this means, if the back pressure is reduced after the intermediate pressure is reduced, the second nozzle hole can be opened before the first nozzle hole.

[Means of claim 5]
According to the fuel injection nozzle of the fifth aspect, the first needle is provided on the first main body portion that opens and closes the first injection hole and the rear end side of the first main body portion, and the hollow on the inner peripheral side is the first needle portion. A first rear end portion that is larger in diameter than the one main body portion and is formed so as to penetrate to the rear end side, and the second needle is slidable in the hollow on the inner peripheral side of the first main body portion. A second main body portion that is accommodated and opens and closes the second nozzle hole, and a second rear portion that is provided on the rear end side of the second main body portion and is slidably accommodated in the hollow on the inner peripheral side of the first rear end portion. And an end. The intermediate chamber is formed between the first main body portion and the second rear end portion.

This means shows one form of the means of claim 3.
According to this means, the intermediate pressure acts on the first needle in the closing direction and acts on the second needle in the opening direction. For this reason, if the intermediate pressure is increased, the first needle becomes difficult to lift, and the second needle becomes easy to lift. Therefore, according to this means, if the back pressure is reduced after increasing the intermediate pressure, the second nozzle hole can be opened earlier than the first nozzle hole.

[Means of claim 6]
According to the fuel injection nozzle of claim 6, the first fuel flow path and the second fuel flow path are an inter-needle flow path formed by the inner peripheral surface of the first needle and the outer peripheral surface of the second needle. And the 1st needle penetration channel provided so that the outer peripheral side of the 1st needle and the inner peripheral side of the 1st needle may be connected, is always connected.
Thereby, a 1st fuel flow path and a 2nd fuel flow path can be connected easily.

[Means of Claim 7]
According to a seventh aspect of the present invention, there is provided a fuel injection device according to the second aspect, a second back pressure operating mechanism that increases or decreases the second back pressure, and a period in which fuel is injected only from the first injection hole. And a control means for instructing the second back pressure operating mechanism to lift the second needle in the opening direction when it becomes longer than the predetermined time.
Thereby, it is possible to easily determine whether or not deposits have accumulated on the inner wall of the second nozzle hole or the peripheral edge of the outer opening, thereby preventing deposits from being deposited or removing the deposited deposits.

[Means of Claim 8]
According to an eighth aspect of the present invention, there is provided a fuel injection device according to the third aspect, wherein the fuel injection nozzle according to the third aspect, the intermediate pressure operating mechanism for increasing / decreasing the intermediate pressure, and the period during which the fuel is injected only from the first injection hole is from a predetermined time. And a control means for instructing the intermediate pressure operating mechanism to lift the second needle in the opening direction.
Thus, in the fuel injection device including the fuel injection nozzle according to claim 3, the same effect as the means of claim 7 can be obtained.

[Means of Claim 9]
An injector according to a ninth aspect includes a fuel injection nozzle according to the second aspect, a first back pressure operating mechanism that increases or decreases a fuel pressure (first back pressure) in the first back pressure chamber, and a second back pressure. And a second back pressure operating mechanism for increasing or decreasing. The first back pressure operation mechanism and the second back pressure operation mechanism are arranged in series in the axial direction.
Thereby, an injector can be constituted by arranging two conventional actuators in series in the axial direction as first and second back pressure operating mechanisms without significant modification. That is, the injector including the fuel injection nozzle according to claim 2 can be easily assembled without significantly improving the conventional actuator.

[Means of Claim 10]
An injector according to a tenth aspect includes the fuel injection nozzle according to the second aspect, a first back pressure operating mechanism that increases or decreases a first back pressure, and a second back pressure operating mechanism that increases or decreases a second back pressure. Prepare. The first back pressure operation mechanism and the second back pressure operation mechanism are arranged in parallel in the axial direction.
Thereby, the injector provided with the fuel injection nozzle according to claim 2 can be assembled so that the axial dimension is substantially the same as that of the conventional injector.

[Means of Claim 11]
According to the injector of claim 11, the first back pressure operating mechanism includes a first valve body that opens and closes the outlet of the first back pressure chamber, and opens the outlet of the first back pressure chamber when energized. A first solenoid coil for displacing the first valve body in a direction to move, and the second back pressure operating mechanism includes a second valve body that opens and closes an outlet of the second back pressure chamber, and a second back body that is energized. A second solenoid coil for displacing the second valve body in a direction to open the outlet of the pressure chamber is provided. The first solenoid coil and the second solenoid coil have an elliptical cross-sectional shape in the axial direction.
According to this means, an electromagnetic actuator is employed as the actuator for the fuel injection nozzle. By providing the first and second solenoid coils with an elliptical cross-sectional shape in the axial direction, the conductors forming the first and second solenoid coils can be lengthened. The acting magnetic attractive force can be strengthened.

[Means of Claim 12]
According to a twelfth aspect of the present invention, an injector includes a fuel injection nozzle according to the second aspect, a first valve body that opens and closes an outlet of the first back pressure chamber, and an outlet of the first back pressure chamber that is energized. A first back pressure operating mechanism that has a first solenoid coil that displaces the first valve body in the opening direction, and that increases or decreases the first back pressure; And a second solenoid coil that has a second solenoid coil that displaces the second valve body in a direction to open the outlet of the second back pressure chamber when energized, and a second back pressure operating mechanism that increases or decreases the second back pressure. One of the first valve body and the second valve body is provided in a cylindrical shape, and the other valve body is slidably disposed on the inner periphery of the one valve body.
Thereby, the injector provided with the fuel injection nozzle according to claim 2 can be assembled so that the axial dimension is substantially the same as that of the conventional injector. Further, since the first and second valve bodies are slidably assembled with each other, the coaxiality is stabilized.

[Means of Claim 13]
According to the injector of the thirteenth aspect, one solenoid coil that displaces one valve body in the first solenoid coil and the second solenoid coil is more than the other solenoid coil that displaces the other valve body. It is arranged on the tip side.
Thereby, a 1st, 2nd valve body can be driven separately reliably.

  The fuel injection nozzle of the best mode 1 includes a cylindrical first needle, a second needle that is accommodated on the inner peripheral side of the first needle, and moves in the same direction as the first needle, and the first needle and the second needle. Is movably accommodated in the axial direction, and is provided on the inner peripheral side of the first nozzle hole that is opened and closed by the tip portion of the first needle and the first nozzle hole, and is opened and closed by the tip portion of the second needle. And a body provided with a second nozzle hole. And in this fuel injection nozzle, the 1st fuel flow path which guides fuel to the tip side of the 1st needle and the 2nd needle are urged in the opening direction so that the 1st needle is urged in the opening direction As described above, the second fuel flow path for guiding the fuel to the distal end side of the second needle is formed, and the first fuel flow path and the second fuel flow path are always in communication.

  In addition, according to the fuel injection nozzle, the first back pressure chamber into which the fuel for energizing the first needle in the closing direction flows in and out, and the first back pressure chamber are formed separately, and the second needle is moved in the closing direction. A second back pressure chamber into which energized fuel flows in and out is formed.

  The first fuel flow path and the second fuel flow path are an inter-needle flow path formed by the inner peripheral surface of the first needle and the outer peripheral surface of the second needle, and the outer peripheral side of the first needle and the first fuel flow path. The first needle penetrating channel provided so as to communicate with the inner peripheral side of the needle is always in communication.

  Further, in the fuel injection device including the fuel injection nozzle, the second back pressure operating mechanism that increases or decreases the second back pressure and the period in which the fuel is injected only from the first injection hole are longer than a predetermined time. And a control means for instructing the second back pressure operating mechanism to lift the second needle in the opening direction.

  According to the fuel injection nozzle of the best mode 2, the back pressure chamber into and out of which the fuel for energizing the first needle and the second needle in the closing direction is formed separately from the back pressure chamber, and the second needle is closed. And an intermediate chamber into which fuel energized in the direction or the opening direction flows in and out.

  The first needle is provided on the first main body portion that opens and closes the first nozzle hole, and on the rear end side of the first main body portion, and the inner peripheral hollow is smaller in diameter than the first main body portion and has a rear end. A first rear end formed so as to penetrate to the side, and the second needle is slidably accommodated in a hollow on the inner peripheral side of the first main body, and opens and closes the second injection hole. 2 main body parts and the 2nd rear end part which is provided in the rear end side of the 2nd main body part, and is slidably accommodated in the hollow of the inner peripheral side of the 1st rear end part. The intermediate chamber is formed between the second main body portion and the first rear end portion.

  Further, the fuel injection device including the fuel injection nozzle includes an intermediate pressure operating mechanism for increasing / decreasing the intermediate pressure and an intermediate pressure when a period during which fuel is injected only from the first injection hole is longer than a predetermined time. Control means for instructing the operating mechanism to lift the second needle in the opening direction.

  According to the fuel injection nozzle of the best mode 3, the first needle is provided on the rear end side of the first main body portion that opens and closes the first injection hole, and the hollow on the inner peripheral side is the first. A first rear end portion that is larger in diameter than the main body portion and formed so as to penetrate to the rear end side, and the second needle is slidably received in the hollow on the inner peripheral side of the first main body portion A second main body portion that opens and closes the second nozzle hole, and a second rear end that is provided on the rear end side of the second main body portion and is slidably accommodated in the hollow on the inner peripheral side of the first rear end portion Part. The intermediate chamber is formed between the first main body portion and the second rear end portion.

  The injector of the best mode 4 includes a first back pressure operation mechanism that increases or decreases the first back pressure and a second back pressure operation mechanism that increases or decreases the second back pressure. The first back pressure operation mechanism and the second back pressure operation mechanism are arranged in series in the axial direction.

  The injector of the best mode 5 includes a first back pressure operation mechanism that increases or decreases the first back pressure, and a second back pressure operation mechanism that increases or decreases the second back pressure. The first back pressure operation mechanism and the second back pressure operation mechanism are arranged in parallel in the axial direction.

  Further, according to this injector, the first back pressure operating mechanism includes a first valve body that opens and closes the outlet of the first back pressure chamber, and a direction that opens the outlet of the first back pressure chamber when energized. A first solenoid coil for displacing the first valve body; the second back pressure operating mechanism includes: a second valve body that opens and closes an outlet of the second back pressure chamber; It has the 2nd solenoid coil which displaces a 2nd valve body in the direction which opens an outflow port. The first solenoid coil and the second solenoid coil have an elliptical cross-sectional shape in the axial direction.

  The injector of the best mode 6 includes a first valve body that opens and closes an outlet of the first back pressure chamber, and a first valve body that is energized to displace the first valve body in a direction of opening the outlet of the first back pressure chamber. A first back pressure operating mechanism that has one solenoid coil to increase or decrease the first back pressure; a second valve body that opens and closes the outlet of the second back pressure chamber; A second back pressure operating mechanism having a second solenoid coil for displacing the second valve body in a direction to open the outlet and increasing or decreasing the second back pressure; One of the first valve body and the second valve body is provided in a cylindrical shape, and the other valve body is slidably disposed on the inner periphery of the one valve body.

  Further, according to this injector, one of the first solenoid coil and the second solenoid coil, one solenoid coil for displacing one valve body is closer to the tip than the other solenoid coil for displacing the other valve body. Has been placed.

[Configuration of Example 1]
A configuration of a fuel injection nozzle 1 (hereinafter referred to as a nozzle 1) and a fuel injection device 2 including the nozzle 1 according to the first embodiment will be described with reference to FIG.

  The nozzle 1 is mounted on each cylinder of an engine (not shown), for example, and receives fuel distribution from a common rail (not shown) that accumulates fuel in a high pressure state and injects the fuel into the cylinder. The fuel injection device 2 includes a nozzle 1, first and second back pressure operating mechanisms 3 and 4 that increase and decrease first and second back pressures described later, and first and second back pressure operating mechanisms 3 and 4. And an electronic control unit (ECU) 5 for giving a command to the computer. The nozzle 1, together with the first and second back pressure operating mechanisms 3 and 4, constitutes an injector 6 that injects and supplies fuel to the engine, and forms the tip of the injector 6.

  As shown in FIG. 1, the nozzle 1 is accommodated in a cylindrical first needle 9, and is slidably accommodated axially on the inner peripheral side of the first needle 9, and moves in the same direction as the first needle 9. Two needles 10, a body 11 into which fuel is guided and accommodates the first and second needles 9 and 10 so as to be movable in the axial direction, and a first spring 12 that urges the first needle 9 in the closing direction And a second spring 13 for urging the second needle 10 in the closing direction.

  The first needle 9 is slidably supported on the body 11. A part of the outer peripheral surface of the first needle 9 is a part of the inner peripheral surface of the body 11, and a first fuel flow path 16 that guides the fuel guided from the common rail to the inside of the body 11 to the first injection hole 14. Form.

  The first needle 9 has a first sheet portion 19 that opens and closes the first injection hole 14 at the tip. Here, the first injection hole 14 opens to the seat surface 20 provided on the inner side of the front end portion of the body 11 and communicates the first fuel flow path 16 and the inside of the cylinder.

  In addition, fuel is guided from the first fuel flow path 16 to a region on the distal end side of the first needle 9 and on the outer peripheral side of the first seat portion 19, and the first needle 9 is always in the opening direction by this fuel. It is energized. That is, the first fuel flow path 16 guides the fuel to the distal end side of the first needle 9 so that the first needle 9 is always urged in the opening direction.

When the pressure of the fuel (first back pressure) in the first back pressure chamber 21 to be described later is reduced and the urging force for urging the first needle 9 in the closing direction is reduced, the urging force in the opening direction is greater. It becomes stronger and the first needle 9 is lifted. As a result, the first seat portion 19 is separated from the seat surface 20, the first injection hole 14 is opened, and fuel is injected into the cylinder through the first injection hole 14.
In the following description, the fuel flow path upstream of the first seat portion 19 in the fuel flow direction in the nozzle 1 is referred to as the first fuel flow path 16.

  Further, a first back pressure chamber 21 into which fuel for energizing the first needle 9 in the closing direction flows in and out is formed on the rear end side of the first needle 9. The first back pressure chamber 21 has its front end side sealed by the first and second needles 9 and 10, and its rear end side sealed by the second needle 10, the rear end surface of the first needle 9, and the outer periphery of the second needle 10. It is formed by the surface and the inner wall surface of the body 11.

  The first back pressure chamber 21 is formed such that fuel flows from the first fuel flow path 16 via the inlet throttle 22 and flows out via the outlet throttle 23. Accordingly, when the fuel flows out from the outlet throttle 23, the first back pressure is reduced, so that the urging force for urging the first needle 9 in the closing direction is reduced. As a result, the first needle 9 is lifted as described above, and fuel is injected into the cylinder through the first injection hole 14.

  Further, when the outflow of fuel from the outlet throttle 23 stops, the first back pressure increases due to the inflow of fuel from the inlet throttle 22, so that the biasing force that biases the first needle 9 in the closing direction increases. As a result, the first needle 9 is lowered, the first seat portion 19 is seated on the seat surface 20, and the first injection hole 14 is closed. Thereby, the fuel injection through the first injection hole 14 is stopped.

  The second needle 10 is housed in sliding contact with the inner peripheral side of the first needle 9, and the front end portion and the rear end portion protrude from the front end side and the rear end side of the first needle 9, respectively.

  A second seat portion 27 that opens and closes the second injection hole 26 is provided at the distal end portion of the second needle 10. Here, the second injection hole 26 is opened to the seat surface 20 similarly to the first injection hole 14 and communicates the second fuel flow path 28 and the inside of the cylinder. It is provided on the inner circumference side. The second fuel flow path 28 is a fuel flow path in the nozzle 1 on the downstream side of the first seat portion 19 in the fuel flow direction and on the upstream side of the second seat portion 27.

  The second fuel flow path 28 is a region on the distal end side of the first and second needles 9 and 10 and on the inner peripheral side with respect to the first seat portion 19 and on the outer peripheral side with respect to the second seat portion 27. When the first needle 9 is lifted, the second fuel flow path 28 communicates with the first fuel flow path 16 to guide the fuel from the first fuel flow path 16, and the second needle 10 is opened in this direction by the fuel. Will be energized. That is, the second fuel flow path 28 guides the fuel to the distal end side of the second needle 10 so that the second needle 10 is biased in the opening direction.

  Further, according to the nozzle 1, the first fuel flow path 16 and the second fuel flow path 28 are formed between the inner peripheral surface of the first needle 9 and the outer peripheral surface of the second needle 10. And the first needle through passage 30 provided so as to communicate the outer peripheral side of the first needle 9 and the inner peripheral side of the first needle 9.

  That is, the first needle penetration channel 30 is provided between the front end and the rear end of the first needle 9 so as to penetrate the first needle 9 in the radial direction. Furthermore, since the inter-needle flow path 29 is formed by the inner peripheral surface of the first needle 9 and the outer peripheral surface of the second needle 10, the inner peripheral surface of the first needle 9 is more distal than the first needle through-flow path 30. A part of the side is recessed on the outer peripheral side from the first needle penetration channel 30 to the tip.

  For this reason, the fuel is always guided from the first fuel flow path 16 to the second fuel flow path 28 via the inter-needle flow path 29 and the first needle through flow path 30, and the second needle 10 is always driven by this fuel. It is biased in the opening direction. When the pressure of the fuel (second back pressure) in the second back pressure chamber 31 described later decreases and the biasing force that biases the second needle 10 in the closing direction is reduced, the biasing force in the opening direction is greater. It becomes stronger and the second needle 10 is lifted. As a result, the second seat portion 27 is separated from the seat surface 20 to open the second injection hole 26, and fuel is injected into the cylinder through the second injection hole 26. That is, even if the first needle 9 is not lifted, the second back pressure can be lowered to lift only the second needle 10 and the second injection hole 26 can be opened.

  The rear end portion of the second needle 10 is in sliding contact with the body 11 to form a second back pressure chamber 31. The second back pressure chamber 31 is a fuel chamber into which fuel for urging the second needle 10 in the closing direction flows in and out, and is formed separately from the first back pressure chamber 21, and the tip side of the second needle 10 is It is sealed off at the rear end, and is formed by the rear end surface of the second needle 10 and the inner wall surface of the body 11.

  The second back pressure chamber 31 is formed such that fuel flows from the first fuel flow path 16 via the inlet throttle 32 and flows out via the outlet throttle 33. Accordingly, when the fuel flows out from the outlet throttle 33, the second back pressure is reduced, so that the urging force for urging the second needle 10 in the closing direction is reduced. As a result, the second needle 10 is lifted as described above, and fuel is injected into the cylinder through the second injection hole 26.

  Further, when the outflow of fuel from the outlet throttle 33 stops, the second back pressure increases due to the inflow of fuel from the inlet throttle 32, so that the biasing force that biases the second needle 10 in the closing direction increases. As a result, the second needle 10 is lowered, the second seat portion 27 is seated on the seat surface 20, and the second injection hole 26 is closed. Thereby, the fuel injection through the second injection hole 26 is stopped.

  The first back pressure operating mechanism 3 is a first valve body 35 that opens and closes the outlet throttle 23 of the first back pressure chamber 21, and generates a magnetic attraction force when energized to displace the first valve body 35 in the opening direction. 1 solenoid coil 36 and a first return spring 37 that biases the first valve body 35 in the closing direction. Then, when the first solenoid coil 36 is energized and the first valve body 35 is displaced in the opening direction, fuel flows out of the first back pressure chamber 21 and the first back pressure is reduced. In addition, the energization of the first solenoid coil 36 is stopped and the first valve body 35 is displaced in the closing direction, whereby the outflow of fuel from the first back pressure chamber 21 is stopped and the first back pressure is increased. .

  The second back pressure operating mechanism 4 includes a second valve body 39 that opens and closes the outlet throttle 33 of the second back pressure chamber 31, and generates a magnetic attraction force when energized to displace the second valve body 39 in the opening direction. 2 comprises a solenoid coil 40 and a second return spring 41 that urges the second valve body 39 in the closing direction. Then, when the second solenoid coil 40 is energized and the second valve element 39 is displaced in the opening direction, the fuel flows out of the second back pressure chamber 31 and the second back pressure is reduced. Further, when the energization of the second solenoid coil 40 is stopped and the second valve body 39 is displaced in the closing direction, the outflow of fuel from the second back pressure chamber 31 is stopped and the second back pressure is increased. .

  The first and second back pressure operating mechanisms 3 and 4 constitute an injector 6 integrally with the nozzle 1 for each cylinder. In addition, energization of the first and second solenoid coils 36 and 40 is interrupted in response to a command from the ECU 5.

  The ECU 5 includes various drive circuits (not shown) for supplying power to the first and second solenoid coils 36, 40, and the like, and a microcomputer (not shown) having a well-known structure that outputs control signals to these drive circuits. And functions as a control means for controlling the first and second back pressure operating mechanisms 3, 4 and the like.

  The microcomputer includes a CPU that performs control processing and arithmetic processing, a storage circuit such as a ROM and RAM that stores various programs and data, an input circuit, an output circuit, and the like. Then, the microcomputer calculates command values for controlling the first and second back pressure operating mechanisms 3, 4, etc. according to detection values input from various sensors that detect the operating state of the engine. A control signal based on the command value is synthesized and output to the drive circuit.

  For example, the microcomputer calculates, as command values, the timing for starting energization of the first and second solenoid coils 36 and 40 and the period of energizing the first and second solenoid coils 36 and 40 according to the operating state of the engine. Then, the control signals based on these command values are synthesized and output to the drive circuit.

  In addition, when the period during which fuel is injected only from the first nozzle hole 14, that is, the period during which the second nozzle hole 26 is closed during engine operation, becomes longer than the predetermined time, the microcomputer The back needle operating mechanism 4 is commanded to lift the second needle 10. That is, the microcomputer uses a command value for energizing the second solenoid coil 40 (that is, the second solenoid) when the period during which the second injection hole 26 is closed during engine operation becomes longer than a predetermined time. A command value for starting energization of the coil 40 and a command value for a period during which the second solenoid coil 40 is energized are calculated, and control signals based on these command values are synthesized and output to the drive circuit.

[Operation 1 of Example 1]
The operation of the nozzle 1 and the fuel injection device 2 according to the first embodiment will be described with reference to FIGS. First, the operation when only the first injection hole 14 is opened and fuel is injected will be described with reference to FIG.
First, when energization of the first solenoid coil 36 is started at time t1, the first valve body 35 is displaced in the opening direction. Thereby, the outflow of fuel from the first back pressure chamber 21 starts, and the first back pressure starts to decrease.

  At time t2, the urging force in the opening direction acting on the first needle 9 (first valve opening urging force: mainly the urging force by the fuel in the first fuel flow path 16 on the distal end side of the first needle 9) is generated. Further, the biasing force in the closing direction acting on the first needle 9 (first valve closing biasing force: mainly the biasing force due to the first back pressure + the biasing force due to the first spring 12) becomes stronger. While starting the lift, the fuel injection rate (first injection rate) from the first injection hole 14 starts to rise (hereinafter, the first back pressure when the first needle 9 starts the lift is first opened. Called the valve value).

  When the energization of the first solenoid coil 36 is stopped at time t3, the first valve body 35 is displaced in the closing direction. Thereby, the outflow of fuel from the first back pressure chamber 21 stops, and the first back pressure starts to increase.

  At time t4, the first valve closing urging force becomes stronger than the first valve opening urging force, the first needle 9 starts to descend, and the first injection rate starts to decrease. Thereafter, the first seat portion 19 is seated on the seat surface 20, the first injection hole 14 is closed, and the first injection rate becomes zero (hereinafter, the first back pressure when the first needle 9 starts to descend). Is called the first valve closing value).

[Operation 2 of Example 1]
Next, the operation when the second injection hole 26 is closed during engine operation is longer than a predetermined time and only the second injection hole 26 is opened and fuel is injected. It explains using.
First, when energization of the second solenoid coil 40 starts at time t1 ′, the second valve body 39 is displaced in the opening direction. Thereby, the outflow of fuel from the second back pressure chamber 31 starts, and the second back pressure starts to decrease.

  Then, at time t2 ′, the urging force in the opening direction acting on the second needle 10 (second valve opening urging force: mainly the urging force by the fuel in the second fuel flow path 28 on the distal end side of the second needle 10). Is stronger than the biasing force in the closing direction acting on the second needle 10 (second valve closing biasing force: mainly the biasing force due to the second back pressure + the biasing force due to the second spring 13). Starts the lift and the fuel injection rate (second injection rate) from the second injection hole 26 starts to rise (hereinafter, the second back pressure when the second needle 10 starts the lift is the second Called the valve opening value).

  When the energization of the second solenoid coil 40 is stopped at time t3 ', the second valve body 39 is displaced in the closing direction. Thereby, the outflow of fuel from the second back pressure chamber 31 stops, and the second back pressure starts to increase.

  At time t4 ', the second valve closing urging force becomes stronger than the second valve opening urging force, the second needle 10 starts to descend, and the second injection rate starts to decrease. Thereafter, the second seat portion 27 is seated on the seat surface 20, the second injection hole 26 is closed, and the second injection rate becomes zero (hereinafter, the second back pressure when the second needle 10 starts to descend). Is called the second valve closing value).

[Operation 3 of Example 1]
Next, an operation when both the first and second injection holes 14 and 26 are opened and fuel is injected will be described with reference to FIG. Here, when the injection amount is large, both the first and second nozzle holes 14 and 26 are opened regardless of the length of the period during which the second nozzle hole 26 is closed during engine operation. Even when the injection amount is small, both the first and second injection holes 14 and 26 can be opened.

  First, when energization of the first solenoid coil 36 is started at time t1, the first valve body 35 is displaced in the opening direction. Thereby, the outflow of fuel from the first back pressure chamber 21 starts, and the first back pressure starts to decrease. At time t2, when the first back pressure is reduced to the first valve opening value, the first needle 9 starts to lift and the first injection rate starts to rise.

  Next, when energization of the second solenoid coil 40 starts at time t1 ', the second valve body 39 is displaced in the opening direction. Thereby, the outflow of fuel from the second back pressure chamber 31 starts, and the second back pressure starts to decrease. When the second back pressure is reduced to the second valve opening value at time t2 ', the second needle 10 starts to lift and the second injection rate starts to increase.

  Eventually, when the energization of both the first and second solenoid coils 36 and 40 is stopped at time t3, both the first and second valve bodies 35 and 39 are displaced in the closing direction. As a result, the outflow of fuel from the first and second back pressure chambers 21 and 31 stops, and the first and second back pressures start to increase.

  At time t4 ', the second back pressure increases to the second valve closing value, the second needle 10 starts to descend, and the second injection rate starts to decrease. Further, at time t4, the first back pressure increases to the first valve closing value, the first needle 9 starts to descend, and the first injection rate starts to decrease. Thereafter, both the first and second seat portions 19 and 27 are seated on the seat surface 20, the first and second injection holes 14 and 26 are closed, and both the first and second injection rates become zero.

[Effect of Example 1]
According to the nozzle 1 of the first embodiment, the first fuel channel 16 and the second fuel channel 28 are always in communication. That is, not only when only the first nozzle hole 14 is opened or when only the second nozzle hole 26 is opened, but also when both the first and second nozzle holes 14 and 26 are opened, Even when both the first and second injection holes 14 and 26 are closed, the first fuel passage 16 and the second fuel passage 28 communicate with each other.
Thereby, even if the 1st needle 9 does not lift, the fuel of the pressure substantially the same as the fuel guide | induced to the front end side of the 1st needle 9 is always guide | induced to the front end side of the 2nd needle 10. FIG. For this reason, since the urging force can always be exerted on the second needle 10 in the opening direction as with the first needle 9, the second needle 10 can be lifted even when the required injection amount is small. Thus, the fuel can be injected from the second injection hole 26. As a result, it is possible to prevent deposits from being deposited on the inner wall of the second nozzle hole 26 and the peripheral edge of the external opening, or to remove the deposited deposits.

Further, the nozzle 1 is formed separately from the first back pressure chamber 21 and the first back pressure chamber 21 through which fuel for energizing the first needle 9 in the closing direction flows in and out, and closes the second needle 10 in the closing direction. And a second back pressure chamber 31 through which fuel energizing the fuel flows in and out.
Thereby, it becomes possible to lift the 2nd needle 10 independently by operating the 2nd back pressure. For this reason, even when the required injection quantity is small, the fuel can be injected from the second injection hole 26 by operating the second back pressure.

Further, according to the nozzle 1, the first back pressure acts only on the first needle 9 in the axial direction, and the second back pressure acts only on the second needle 10 in the axial direction.
Thereby, the lift of the 1st needle 9 and the lift of the 2nd needle 10 can be controlled completely independently. For this reason, the transition characteristic of the total injection rate obtained by adding up the first injection rate and the second injection rate can be freely operated. Therefore, for example, the transition characteristic of the total injection rate is manipulated so that there is no time difference between the seating of the second seat portion 27 on the seat surface 20 and the seating of the first seat portion 19 on the seat surface 20. Can do.

The first fuel flow path 16 and the second fuel flow path 28 include an inter-needle flow path 29 formed by the inner peripheral surface of the first needle 9 and the outer peripheral surface of the second needle 10, and the first needle 9. The outer peripheral side of the first needle 9 and the inner peripheral side of the first needle 9 are always in communication with each other by the first needle through passage 30 provided so as to communicate therewith.
Thereby, the 1st fuel flow path 16 and the 2nd fuel flow path 28 can be connected easily.

Further, the microcomputer of the ECU 5 instructs the second back pressure operating mechanism 4 to instruct the second needle 10 when the period during which the second injection hole 26 is closed during engine operation becomes longer than a predetermined time. Lift.
Thereby, it is possible to easily determine whether or not deposits have accumulated on the inner wall of the second nozzle hole 26 or the periphery of the outer opening, thereby preventing the deposits from being deposited or removing the deposited deposits.

[Configuration of Example 2]
Configurations of the nozzle 1 and the fuel injection device 2 according to the second embodiment will be described with reference to FIG.
First, the fuel injection device 2 according to the second embodiment includes a nozzle 1, a back pressure operating mechanism 43 that increases and decreases the fuel pressure (back pressure) in the back pressure chamber 52 described later, and the fuel pressure (in the intermediate chamber 56 described later ( An intermediate pressure operation mechanism 44 for increasing / decreasing the intermediate pressure), and an ECU 5 for giving commands to the back pressure and intermediate pressure operation mechanisms 43 and 44.

  Further, according to the nozzle 1 of the second embodiment, the first needle 9 is provided on the rear end side of the first main body portion 46 that opens and closes the first injection hole 14 and the first main body portion 46, The hollow has a first rear end portion 47 which is smaller in diameter than the first main body portion 46 and formed so as to penetrate to the rear end side. The second needle 10 is slidably accommodated in a hollow on the inner peripheral side of the first main body 46, and a second main body 49 that opens and closes the second injection hole 26, and a rear end of the second main body 49 And a second rear end portion 50 that is slidably received in a hollow on the inner peripheral side of the first rear end portion 47.

  A back pressure chamber 52 is formed on the rear end side of the first and second rear end portions 47 and 50. The back pressure chamber 52 into and out of which the fuel that urges the first and second needles 9 and 10 in the closing direction is formed. A second rear end portion 50 projects from the pressure chamber 52. That is, the back pressure chamber 52 is sealed at the front end side with the first and second rear end portions 47, 50, and the rear end surface of the first rear end portion 47, the rear end surface and the outer peripheral surface of the second rear end portion 50, and It is formed by the inner wall surface of the body 11.

  The back pressure chamber 52 is formed such that fuel flows from the first fuel flow path 16 through the inlet throttle 53 and flows out through the outlet throttle 54. As a result, when the fuel flows out from the outlet throttle 54, the back pressure is reduced, so that the urging force for urging the first and second needles 9 and 10 in the closing direction is reduced. Further, when the outflow of fuel from the outlet throttle 54 stops, the back pressure increases due to the inflow of fuel from the inlet throttle 53, so that the urging force for urging the first and second needles 9 and 10 in the closing direction increases. To do.

  Further, an intermediate chamber 56 is formed between the second main body portion 49 and the first rear end portion 47, in addition to the back pressure chamber 52, in which fuel for energizing the second needle 10 in the closing direction flows in and out. ing. The intermediate chamber 56 is sealed at the front end side by the second main body part 49, and at the rear end side by the second rear end part 50, the rear end surface of the second main body part 49, and the outer peripheral surface of the second rear end part 50. The inner peripheral surface of the first main body portion 46 and the front end surface of the first rear end portion 47 are formed. For this reason, the fuel in the intermediate chamber 56 urges the second needle 10 in the closing direction and simultaneously urges the first needle 9 in the opening direction.

  Further, in the intermediate chamber 56, the fuel flows out through an intermediate chamber inflow passage 57 and an intermediate chamber outflow passage 58 provided through the inner peripheral side of the first main body portion 46 and the outer peripheral side of the first main body portion 46. Formed to enter. Further, the body 11 is provided with a fuel chamber 59 in an annular and groove shape for allowing fuel to flow in and out between the intermediate chamber inflow passage 57 and the intermediate chamber outflow passage 58. Blocked. The fuel chamber 59 is formed such that fuel flows from the first fuel flow path 16 through the inlet throttle 60 and flows out through the outlet throttle 61.

  Thereby, when the fuel flows out from the outlet throttle 61, the intermediate pressure is reduced, so that the urging force for urging the second needle 10 in the closing direction is reduced and the urging force for urging the first needle 9 in the opening direction. Is reduced. Further, when the outflow of fuel from the outlet throttle 61 stops, the intermediate pressure increases due to the inflow of fuel from the inlet throttle 60, so that the biasing force that biases the second needle 10 in the closing direction increases, and the first The urging force that urges the needle 9 in the opening direction increases.

  Here, the axial pressure receiving area of the back pressure in the first and second needles 9 and 10, the axial pressure receiving area of the intermediate pressure in the first and second needles 9 and 10, and the first and second springs 12 and 13. The design conditions such as the urging force and the pressure receiving area of the fuel pressure on the tip side of the first and second needles 9 and 10 are determined so that the following operation is possible. That is, the design conditions are determined so that the second needle 10 does not lift even if only the intermediate pressure is reduced, and the second needle 10 is lifted before the first needle 9 when the back pressure is further reduced. It has been.

  Thereby, by reducing the back pressure in a state where the intermediate pressure is reduced, the second needle 10 can be lifted before the first needle 9 or the second needle 10 can be lifted alone. Further, by reducing the back pressure in a state where the intermediate pressure is not reduced, the first needle 9 can be lifted first, or the first needle 9 can be lifted alone, as is conventional.

  The intermediate chamber inflow passage 57, the intermediate chamber outflow passage 58, and the fuel chamber 59 are arranged on the inner and outer peripheral sides of the intermediate chamber inflow passage 57 even when the first and second needles 9 and 10 are displaced in the axial direction. The openings and the opening areas of the inner and outer peripheral openings of the intermediate chamber outflow passage 58 are provided so as not to change. Further, since the fuel chamber 59 is provided in an annular shape, even if the first needle 9 rotates in the body 11, the opening areas of the outer peripheral side openings of the intermediate chamber inflow passage 57 and the intermediate chamber outflow passage 58 are changed. do not do.

  The back pressure operating mechanism 43 includes a main valve body 64 that opens and closes the outlet throttle 54 of the back pressure chamber 52, a main solenoid coil 65 that receives current to generate a magnetic attractive force, and displaces the main valve body 64 in the opening direction. The main return spring 66 urges the body 64 in the closing direction. When the main solenoid coil 65 is energized and the main valve body 64 is displaced in the opening direction, the fuel flows out from the back pressure chamber 52 and the back pressure is reduced. Further, the energization of the main solenoid coil 65 is stopped and the main valve body 64 is displaced in the closing direction, whereby the outflow of fuel from the back pressure chamber 52 is stopped and the back pressure is increased.

  The intermediate pressure operating mechanism 44 includes an intermediate valve body 68 that opens and closes the outlet throttle 61 of the fuel chamber 59, an intermediate solenoid coil 69 that receives current to generate a magnetic attractive force and displaces the intermediate valve body 68 in the opening direction, and an intermediate valve body. It is constituted by an intermediate return spring 70 that biases 68 in the closing direction. When the intermediate solenoid coil 69 is energized and the intermediate valve body 68 is displaced in the opening direction, the fuel flows out of the intermediate chamber 56 and the fuel chamber 59 and the intermediate pressure is reduced. Further, the energization of the intermediate solenoid coil 69 is stopped and the intermediate valve body 68 is displaced in the closing direction, whereby the outflow of fuel from the intermediate chamber 56 and the fuel chamber 59 is stopped and the intermediate pressure is increased.

  The back pressure operation mechanism 43 forms an injector 6 integrally with the nozzle 1 for each cylinder, and the intermediate pressure operation mechanism 44 is shared by all the injectors 6 and is provided separately from the injectors 6. . That is, the fuel injection device 2 according to the second embodiment includes one intermediate pressure operating mechanism 44 for the injectors 6 corresponding to the number of cylinders of the engine. In addition, energization of the main solenoid coil 65 and the intermediate solenoid coil 69 is interrupted in response to a command from the ECU 5.

  The ECU 5 includes various drive circuits for supplying power to the main solenoid coil 65, the intermediate solenoid coil 69, and the like, and a microcomputer having a known structure that outputs control signals to these drive circuits. It functions as a control means for controlling the operation mechanisms 43, 44 and the like.

  The microcomputer calculates command values for controlling the back pressure and intermediate pressure operating mechanisms 43, 44, etc., synthesizes control signals based on these command values, and outputs them to the drive circuit. For example, the microcomputer calculates, as command values, the timing for starting energization of the main solenoid coil 65 and the intermediate solenoid coil 69 and the period of energization of the main solenoid coil 65 and the intermediate solenoid coil 69 according to the operating state of the engine. A control signal based on the command value is synthesized and output to the drive circuit.

  The microcomputer also instructs the intermediate pressure operating mechanism 44 to reduce the intermediate pressure when the period during which the second injection hole 26 is closed during engine operation becomes longer than a predetermined time, and then reduces the back pressure. The pressure operating mechanism 43 is commanded to reduce the back pressure and lift the second needle 10. That is, the microcomputer determines a command value for energizing the intermediate solenoid coil 69 (that is, the intermediate solenoid coil 69) when the period during which the second injection hole 26 is closed during engine operation becomes longer than a predetermined time. The command value at the time of starting energization and the command value of the period during which the intermediate solenoid coil 69 is energized are calculated, and control signals based on these command values are synthesized and output to the drive circuit.

[Operation 1 of Example 2]
The operation of the nozzle 1 and the fuel injection device 2 according to the second embodiment will be described with reference to FIGS. First, when the required injection amount is small, the first needle 9 can be lifted independently as usual by reducing the back pressure without reducing the intermediate pressure. The operation when the first needle 9 is lifted alone will be described with reference to FIGS. 6 and 7.

  FIG. 6 shows the urging force by the fuel acting in the axial direction of the first and second needles 9 and 10. F1 is an urging force (first back pressure urging force) exerted on the first needle 9 by the fuel in the back pressure chamber 52, and F2 is exerted on the first needle 9 by fuel on the tip side of the first needle 9. F3 is a biasing force (first intermediate biasing force) exerted on the first needle 9 by the fuel in the intermediate chamber 56. F4 is an urging force (second back pressure urging force) exerted on the second needle 10 by the fuel in the back pressure chamber 52, and F5 is exerted on the second needle 10 by the fuel on the tip side of the second needle 10. F6 is a biasing force (second intermediate biasing force) exerted by the fuel in the intermediate chamber 56 on the second needle 10.

  As for the urging force by the fuel acting on the first needle 9, the first back pressure urging force F1 acts in the closing direction, and the first tip side urging force F2 and the first intermediate urging force F3 act in the opening direction. To do. As for the urging force by the fuel acting on the second needle 10, the second back pressure urging force F4 and the second intermediate urging force F6 act in the closing direction, and the second tip side urging force F5 acts in the opening direction. To do.

That is, for the first needle 9, the first back pressure urging force F1 forms the first valve closing urging force together with the urging force (first spring force) Fs1 and the like by the first spring 12, and the first tip side urging force F2 and The first intermediate biasing force F3 and the like constitute a first valve opening biasing force. Further, with respect to the second needle 10, the second back pressure biasing force F4 and the second intermediate pressure biasing force F6 form the second valve closing biasing force together with the biasing force (second spring force) Fs2 by the second spring 13, etc. The second tip side urging force F5 and the like constitute a second valve opening urging force (hereinafter, a first valve closing urging force F1 + Fs1, a first valve opening urging force F2 + F3, a second valve closing urging force F4 + F6 + Fs2, and a second valve opening urging force). (Indicated as power F5).
Hereinafter, the operation will be described with reference to the time chart shown in FIG.

  First, when energization to the main solenoid coil 65 starts at time t5, the main valve body 64 is displaced in the opening direction. Thereby, the outflow of fuel from the back pressure chamber 52 starts and the back pressure starts to be reduced. Further, since the intermediate solenoid coil 69 is not energized and the intermediate valve body 68 is not displaced in the opening direction, fuel does not flow out from the intermediate chamber 56 and the intermediate pressure is not reduced. Note that since the fuel flows into the back pressure chamber 52 and the intermediate chamber 56 from the first fuel flow path 16, the back pressure and the intermediate pressure before time t5 are equal to each other.

  When the back pressure is reduced, the first and second back pressure biasing forces F1 and F4 are weakened. On the other hand, since the intermediate pressure is not reduced, the first and second intermediate biasing forces F3 and F6 change with the same strength. Further, the first and second distal end side urging forces F2 and F5 also change with the same strength. For this reason, the first and second valve opening urging forces F2 + F3 and F5 change with the same strength, while the first and second valve closing urging forces F1 + Fs1 and F4 + F6 + Fs2 are weakened.

  Therefore, at time t6, the first valve closing biasing force F1 + Fs1 becomes weaker than the first valve opening biasing force F2 + F3, the first needle 9 starts to lift, and the first injection rate starts to increase. Before the second valve closing urging force F4 + F6 + Fs2 becomes weaker than the second valve opening urging force F5, the back pressure stops decreasing, so the second needle 10 does not lift and the second injection hole 26 is closed. Will remain.

  When the energization of the main solenoid coil 65 is stopped at time t7, the main valve body 64 is displaced in the closing direction. As a result, the outflow of fuel from the back pressure chamber 52 stops and the back pressure starts to increase.

  At time t8, the first valve closing biasing force F1 + Fs1 becomes stronger than the first valve opening biasing force F2 + F3, the first needle 9 starts to descend, and the first injection rate starts to decrease. Thereafter, the first seat portion 19 is seated on the seat surface 20, the first injection hole 14 is closed, and the first injection rate becomes zero.

[Operation 2 of Example 2]
Next, when the required injection amount is small, the second needle 10 can be lifted independently by reducing the back pressure while reducing the intermediate pressure. Thus, the effect | action in the case of lifting the 2nd needle 10 independently is demonstrated using FIG.
In this case, since the intermediate pressure is reduced, the first valve opening urging force F2 + F3 and the second valve closing urging force F4 + F6 + Fs2 are generally weaker than when the intermediate pressure is not reduced.

  First, when energization to the main solenoid coil 65 starts at time t5 ', the main valve body 64 is displaced in the opening direction. Thereby, the outflow of fuel from the back pressure chamber 52 starts and the back pressure starts to be reduced. Further, since the intermediate solenoid coil 69 has already been energized by a command from the ECU 5 and the intermediate valve body 68 has been displaced in the opening direction, the fuel has flowed out of the intermediate chamber 56 and the intermediate pressure has been reduced. maintain.

  When the back pressure is reduced, the first and second back pressure urging forces F1 and F4 are weakened. On the other hand, since the intermediate pressure remains unchanged, the first and second intermediate urging forces F3 and F6 are the same. It changes with strength. Further, the first and second distal end side urging forces F2 and F5 also change with the same strength. For this reason, the first and second valve opening urging forces F2 + F3 and F5 change with the same strength, while the first and second valve closing urging forces F1 + Fs1 and F4 + F6 + Fs2 are weakened.

  Therefore, at time t6 ', the second valve closing biasing force F4 + F6 + Fs2 becomes weaker than the second valve opening biasing force F5, the second needle 10 starts to lift, and the second injection rate starts to increase. Before the first valve closing biasing force F1 + Fs1 becomes weaker than the first valve opening biasing force F2 + F3, the back pressure stops decreasing, so the first needle 9 does not lift and the first injection hole 14 is closed. Will remain.

  When the energization of the main solenoid coil 65 is stopped at time t7 ', the main valve body 64 is displaced in the closing direction. As a result, the outflow of fuel from the back pressure chamber 52 stops and the back pressure starts to increase.

  At time t8 ', the second valve closing biasing force F4 + F6 + Fs2 becomes stronger than the second valve opening biasing force F5, the second needle 10 starts to descend, and the second injection rate starts to decrease. Thereafter, the second seat portion 27 is seated on the seat surface 20, the second injection hole 26 is closed, and the second injection rate becomes zero.

[Effect of Example 2]
According to the nozzle 1 of the second embodiment, the back pressure chamber 52 into and out of which the fuel for energizing the first and second needles 9 and 10 in the closing direction is formed separately from the back pressure chamber 52, and the second needle An intermediate chamber 56 into which fuel for energizing 10 in the closing direction flows in and out is formed.

  Thereby, the 2nd needle 10 can receive back pressure and intermediate pressure separately. For this reason, even if only the intermediate pressure is reduced, the second needle 10 is not lifted, and when the back pressure is further reduced, the second needle 10 is lifted before the first needle 9. Design conditions such as the pressure receiving area and the intermediate pressure receiving area can be determined.

  As a result, the intermediate pressure operating mechanism 44 that increases or decreases the intermediate pressure can be shared by all the nozzles 1. For this reason, even when the required injection amount is small, the fuel can be injected from the second injection hole 26 and the number of mechanisms for operating the fuel pressure inside the nozzle 1 can be reduced.

  Further, according to the nozzle 1, the first needle 9 is provided on the first main body portion 46 that opens and closes the first injection hole 14 and the rear end side of the first main body portion 46, and the hollow on the inner peripheral side is the first. A first rear end portion 47 having a smaller diameter than the main body portion 46 and penetrating to the rear end side, and the second needle 10 is slid into a hollow on the inner peripheral side of the first main body portion 46. A second body portion 49 that is movably accommodated and opens and closes the second nozzle hole 26, and is provided on the rear end side of the second body portion 49, and is slidable in the hollow on the inner peripheral side of the first rear end portion 47. And a second rear end portion 50 accommodated therein. The intermediate chamber 56 is formed between the second main body portion 49 and the first rear end portion 47.

  Thereby, the intermediate pressure acts on the first needle 9 in the opening direction and acts on the second needle 10 in the closing direction. For this reason, if the intermediate pressure is reduced, the first needle 9 becomes difficult to lift, and the second needle 10 becomes easy to lift. Therefore, if the back pressure is reduced after reducing the intermediate pressure, the second injection hole 26 can be opened before the first injection hole 14.

[Configuration of Example 3]
The configuration of the nozzle 1 and the fuel injection device 2 according to the third embodiment will be described with reference to FIG.
First, the fuel injection device 2 according to the third embodiment includes the nozzle 1, the back pressure operation mechanism 43, the intermediate pressure operation mechanism 44, and the ECU 5, similarly to the fuel injection device 2 according to the second embodiment.

  Further, according to the nozzle 1 of the third embodiment, the hollow on the inner peripheral side of the first rear end portion 47 is formed larger in diameter than the hollow on the inner peripheral side of the first main body portion 46. Therefore, the intermediate chamber 56 is formed between the first main body portion 46 and the second rear end portion 50, and the fuel in the intermediate chamber 56 urges the second needle 10 in the opening direction and the first needle 9. Energize in the closing direction.

  Therefore, when the fuel flows out from the outlet throttle 61 and the intermediate pressure is reduced, the urging force for urging the second needle 10 in the opening direction is reduced and the urging force for urging the first needle 9 in the closing direction is reduced. . Further, when the outflow of fuel from the outlet throttle 61 stops and the intermediate pressure increases due to the inflow of fuel from the inlet throttle 60, the biasing force that biases the second needle 10 in the opening direction increases, and the first needle 9 The biasing force that biases in the closing direction increases.

  Here, the axial pressure receiving area of the back pressure in the first and second needles 9 and 10, the axial pressure receiving area of the intermediate pressure in the first and second needles 9 and 10, and the first and second springs 12 and 13. The design conditions such as the urging force and the pressure receiving area of the fuel pressure on the tip side of the first and second needles 9 and 10 are determined so that the following operation is possible. That is, the design conditions are determined so that the second needle 10 does not lift even if only the intermediate pressure is increased, and the second needle 10 is lifted before the first needle 9 when the back pressure is further reduced. It has been.

  Thereby, by reducing the back pressure in a state where the intermediate pressure is increased, the second needle 10 can be lifted before the first needle 9 or the second needle 10 can be lifted alone. Further, by reducing the back pressure in a state where the intermediate pressure is not increased, the first needle 9 can be lifted first or the first needle 9 can be lifted alone as usual.

  Similar to the fuel injection device 2 of the second embodiment, the back pressure operation mechanism 43 is integrated with the nozzle 1 for each cylinder to constitute the injector 6, and the intermediate pressure operation mechanism 44 is common to all the injectors 6. And is provided separately from the injector 6. That is, the fuel injection device 2 according to the third embodiment includes one intermediate pressure operating mechanism 44 for the injectors 6 corresponding to the number of cylinders of the engine.

[Effect of Example 3]
According to the nozzle 1 of the third embodiment, the hollow on the inner peripheral side of the first rear end portion 47 is formed larger in diameter than the hollow on the inner peripheral side of the first main body portion 46. Therefore, the intermediate chamber 56 is formed between the first main body portion 46 and the second rear end portion 50, and the fuel in the intermediate chamber 56 urges the second needle 10 in the opening direction and the first needle 9. Energize in the closing direction.
As a result, if the intermediate pressure is increased, the first needle 9 becomes difficult to lift and the second needle 10 becomes easy to lift. Therefore, according to this means, if the back pressure is reduced after increasing the intermediate pressure, the second injection hole 26 can be opened earlier than the first injection hole 14.

[Configuration of Example 4]
The structure of the injector 6 of Example 4 is demonstrated using FIG. The nozzle 1 constituting the injector 6 of the fourth embodiment is the nozzle 1 of the first embodiment, and the first and second back pressure operating mechanisms 3 and 4 have the same functions as those of the first embodiment. And according to the injector 6 of Example 4, the 1st, 2nd back pressure operation mechanisms 3 and 4 are arrange | positioned in series in the axial direction. That is, the injector 1 is configured by sequentially incorporating the nozzle 1, the second back pressure operating mechanism 4, and the first back pressure operating mechanism 3 in the axial direction from the front end to the rear end.

  According to the first back pressure operating mechanism 3 of the fourth embodiment, the first valve body 35 is provided at the front end to the first valve portion 72 that opens and closes the outlet throttle 23 and to the first solenoid coil 36 provided at the rear end. A first armature portion 73 that is magnetically attracted by the energization of the first armature portion, and a first intermediate body portion 74 that connects the first armature portion 73 and the first valve portion 72. The first solenoid coil 36 is disposed on the rear end side of the first armature portion 73, and the first return spring 37 is disposed on the inner peripheral side of the first solenoid coil 36.

  The first valve portion 72, the first armature portion 73, and the first return spring 37 are accommodated in the first valve chamber 75, the first armature chamber 76, and the first spring chamber 77, respectively. The first valve chamber 75, the first armature chamber 76, and the first spring chamber 77 are always in communication with a fuel passage 80 that guides the fuel in the injector 6 to the outside of the injector 6.

  When the first armature portion 73 is magnetically attracted and the first valve portion 72 opens the outlet throttle 23, fuel flows out from the first back pressure chamber 21 to the first valve chamber 75, and the first back pressure is reduced. The fuel that has flowed into the first valve chamber 75 flows out of the injector 6 through the fuel passage 80.

  According to the second back pressure operating mechanism 4 of the fourth embodiment, the second valve body 39 is provided at the front end to the second valve portion 82 that opens and closes the outlet throttle 33, and is provided at the rear end to the second solenoid coil 40. A second armature portion 83 that is magnetically attracted by the energization of the second armature portion, and a second intermediate body portion 84 that connects the second armature portion 83 and the second valve portion 82. The second solenoid coil 40 is disposed on the rear end side of the second armature portion 83, and the second return spring 41 is disposed on the inner peripheral side of the second solenoid coil 40.

  The second valve portion 82, the second armature portion 83, and the second return spring 41 are accommodated in the second valve chamber 85, the second armature chamber 86, and the second spring chamber 87, respectively. The second valve chamber 85, the second armature chamber 86 and the second spring chamber 87 are always in communication with the fuel passage 80.

  When the second armature portion 83 is magnetically attracted and the second valve portion 82 opens the outlet throttle 33, fuel flows out from the second back pressure chamber 31 to the second valve chamber 85, and the second back pressure is reduced. The fuel that has flowed into the second valve chamber 85 flows out of the injector 6 through the fuel passage 80.

[Effect of Example 4]
According to the injector 6 of the fourth embodiment, the first and second back pressure operation mechanisms 3 and 4 are arranged in series in the axial direction.
Thus, the injector 6 can be configured by arranging two conventional actuators in series in the axial direction as the first and second back pressure operating mechanisms 3 and 4 without significantly remodeling. That is, the injector 6 can be easily assembled without significantly improving the conventional actuator.

[Configuration of Example 5]
The structure of the injector 6 of Example 5 is demonstrated using FIG. The nozzle 1 constituting the injector 6 of the fifth embodiment is the nozzle 1 of the first embodiment, and the first and second back pressure operating mechanisms 3 and 4 have the same functions as those of the first embodiment. According to the injector 6 of the fifth embodiment, the first and second back pressure operation mechanisms 3 and 4 are arranged in parallel in the axial direction. That is, the first and second back pressure operating mechanisms 3 and 4 are incorporated in parallel on the rear end side of the nozzle 1 to constitute the injector 6.

According to the first and second back pressure operation mechanisms 3 and 4 of the fifth embodiment, the first and second valve portions 72 and 82 are accommodated in the common valve chamber 89, and the first and second armature portions 73, 83 is accommodated in a common armature chamber 90. The valve chamber 89, the armature chamber 90, and the first and second spring chambers 77 and 87 are always in communication with the fuel passage 80.
The first and second solenoid coils 36 and 40 have an elliptical cross section in the axial direction.

  When the first armature portion 73 is magnetically attracted and the first valve portion 72 opens the outlet throttle 23, fuel flows out from the first back pressure chamber 21 to the valve chamber 89, and the second armature portion 83 is magnetically attracted. When the two-valve part 82 opens the outlet throttle 33, fuel flows out from the second back pressure chamber 31 to the valve chamber 89. The fuel that has flowed into the valve chamber 89 flows out of the injector 6 through the fuel passage 80.

[Effect of Example 5]
According to the injector 6 of the fifth embodiment, the first and second back pressure operating mechanisms 3 and 4 are arranged in parallel in the axial direction.
Thereby, the injector 6 provided with the nozzle 1 can be assembled so that the dimension of an axial direction may become substantially the same as a conventional product.

The first and second solenoid coils 36 and 40 have an elliptical cross section in the axial direction.
Thereby, since the conducting wire which forms the 1st, 2nd solenoid coils 36 and 40 can be lengthened, the magnetic attraction force which acts on the 1st, 2nd armature parts 73 and 83 can be strengthened.

[Configuration of Example 6]
The structure of the injector 6 of Example 6 is demonstrated using FIG. The nozzle 1 constituting the injector 6 of the sixth embodiment is the nozzle 1 of the first embodiment, and the first and second back pressure operating mechanisms 3 and 4 have the same functions as those of the first embodiment. According to the injector 6 of the sixth embodiment, the first valve body 35 is provided in a cylindrical shape, and the second valve body 39 is slidably disposed on the inner periphery of the first valve body 35. Further, the first solenoid coil 36 is disposed on the tip side of the second solenoid coil 40.

  That is, the first valve body 35 has a through hole penetrating in the axial direction, and the portion on the distal end side of the second intermediate body portion 84 and the second valve portion 82 are accommodated in the through hole. The rear end portion of the second intermediate body portion 84 and the second armature portion 83 protrude toward the rear end side of the first armature portion 73. Further, the diameter of the second valve portion 82 is smaller than the diameter of the through hole, and the tip side portion of the second intermediate body portion 84 is two flat surfaces symmetrically across the axis and parallel to the axis. 92 is provided. A fuel passage 93 is formed by the flat surface 92 and the inner peripheral surface of the first valve body 35.

  Further, according to the first valve body 35 of the sixth embodiment, the annular groove 94 is provided at the tip of the first intermediate body portion 74, and the tip of the first intermediate body portion 74 forms the first valve portion 72. The first and second valve portions 72 and 82 are accommodated in a common valve chamber 89. The valve chamber 89, the first and second armature chambers 76 and 86, and the second spring chamber 87 are always in communication with the fuel passage 80. The first spring chamber 77 communicates with the first armature chamber 76 and communicates with the fuel passage 80 via the first armature chamber 76.

  When only the second armature portion 83 is magnetically attracted and the second valve portion 82 opens the outlet throttle 33, the fuel in the second back pressure chamber 31 flows into the first spring chamber 77 via the fuel passage 93, Further, fuel flows from the first spring chamber 77 into the first armature chamber 76 and flows out of the injector 6 through the fuel passage 80. When only the first armature portion 73 is magnetically attracted and the first valve portion 72 opens the outlet throttle 23, the fuel in the first back pressure chamber 21 flows into the valve chamber 89 and enters the injector 6 via the fuel passage 80. It flows out to the outside.

[Effect of Example 6]
According to the injector 6 of the sixth embodiment, the first valve body 35 is provided in a cylindrical shape, and the second valve body 39 is slidably disposed on the inner periphery of the first valve body 35.
Thereby, the injector 6 provided with the nozzle 1 of Example 1 can be assembled so that the dimension of an axial direction may become substantially the same as a conventional product. Further, since the first and second valve bodies 35 and 39 are slidably assembled with each other, the coaxiality is stabilized.

Further, the first solenoid coil 36 is disposed on the tip side of the second solenoid coil 40.
Thereby, the 1st, 2nd valve bodies 35 and 39 can be driven individually reliably.

[Modification]
According to the injector 6 of the fourth embodiment, the second back pressure operating mechanism 4 is disposed on the distal end side of the first back pressure operating mechanism 3, but the first back pressure operating mechanism 3 is replaced with the second back pressure operating mechanism 4. You may arrange | position to the front end side.
Further, according to the injector 6 of the sixth embodiment, the first valve body 35 is provided in a cylindrical shape, and the second valve body 39 is slidably disposed on the inner periphery of the first valve body 35. The two valve bodies 39 may be provided in a cylindrical shape, and the first valve body 35 may be slidably disposed on the inner periphery of the second valve body 39.

1 is a configuration diagram of a fuel injection nozzle and a fuel injection device (Example 1). FIG. It is a time chart which shows the effect | action of a fuel-injection nozzle and a fuel-injection apparatus (Example 1). It is a time chart which shows the effect | action of a fuel-injection nozzle and a fuel-injection apparatus (Example 1). It is a time chart which shows the effect | action of a fuel-injection nozzle and a fuel-injection apparatus (Example 1). (Example 2) which is a block diagram of a fuel-injection nozzle and a fuel-injection apparatus. (A) is explanatory drawing which shows the urging | biasing force by the fuel which acts on a 1st needle, (b) is explanatory drawing which shows the urging | biasing force by the fuel which acts on a 2nd needle (Example 2). (Example 2) which is a time chart which shows the effect | action of a fuel-injection nozzle and a fuel-injection apparatus. (Example 2) which is a time chart which shows the effect | action of a fuel-injection nozzle and a fuel-injection apparatus. (Example 3) which is a block diagram of a fuel-injection nozzle and a fuel-injection apparatus. (A) is a block diagram of an injector, (b) is AA sectional drawing of (a) (Example 4). (A) is a block diagram of an injector, (b) is a BB sectional view of (a), and (c) is a CC sectional view of (a) (Example 5). (A) is the block diagram of an injector, (b) is DD sectional drawing of (a), (c) is EE sectional drawing of (a) (Example 6).

Explanation of symbols

1 Nozzle (fuel injection nozzle)
2 Fuel injector 3 First back pressure operation mechanism 4 Second back pressure operation mechanism 5 ECU (control means)
6 Injector 9 1st needle 10 2nd needle 11 Body 14 1st injection hole 16 1st fuel flow path 21 1st back pressure chamber 26 2nd injection hole 28 2nd fuel flow path 29 Inter-needle flow path 30 1st needle penetration Flow path 31 Second back pressure chamber 35 First valve body 36 First solenoid coil 39 Second valve body 40 Second solenoid coil 44 Intermediate pressure operating mechanism 46 First main body portion 47 First rear end portion 49 Second main body portion 50 Second rear end portion 52 Back pressure chamber 56 Intermediate chamber

Claims (13)

A cylindrical first needle;
A second needle housed on the inner peripheral side of the first needle and moving coaxially with the first needle;
The first needle and the second needle are accommodated so as to be movable in the axial direction, and are provided on the inner peripheral side of the first nozzle hole opened and closed by the tip of the first needle and the first nozzle hole. A fuel injection nozzle including a body provided with a second injection hole that is opened and closed by a tip portion of the second needle,
A first fuel flow path that guides fuel to a tip side of the first needle so that the first needle is biased in an opening direction;
A second fuel flow path for guiding fuel to the tip side of the second needle is formed so that the second needle is biased in the opening direction;
The fuel injection nozzle, wherein the first fuel passage and the second fuel passage are always in communication. The fuel injection nozzle according to claim 1,
A first back pressure chamber into and out of which fuel for energizing the first needle in the closing direction;
A fuel injection nozzle formed separately from the first back pressure chamber, wherein a second back pressure chamber into which fuel for energizing the second needle in the closing direction flows in and out is formed. The fuel injection nozzle according to claim 1,
A back pressure chamber into and out of which fuel for energizing the first needle and the second needle in the closing direction;
A fuel injection nozzle formed separately from the back pressure chamber and having an intermediate chamber into and out of which fuel for energizing the second needle in a closing direction or an opening direction is formed. The fuel injection nozzle according to claim 3,
The first needle is provided on a first body portion that opens and closes the first nozzle hole, and a rear end side of the first body portion, and an inner peripheral hollow is smaller in diameter than the first body portion, and A first rear end portion formed so as to penetrate the rear end side,
The second needle is slidably accommodated in a hollow on the inner peripheral side of the first main body, and is provided on the rear end side of the second main body that opens and closes the second injection hole. A second rear end portion slidably received in a hollow on the inner peripheral side of the first rear end portion,
The fuel injection nozzle according to claim 1, wherein the intermediate chamber is formed between the second main body portion and the first rear end portion. The fuel injection nozzle according to claim 3,
The first needle is provided on a first body portion that opens and closes the first nozzle hole, and a rear end side of the first body portion, and an inner peripheral hollow is larger in diameter than the first body portion, and A first rear end portion formed so as to penetrate the rear end side,
The second needle is slidably accommodated in a hollow on the inner peripheral side of the first main body, and is provided on the rear end side of the second main body that opens and closes the second injection hole. A second rear end portion slidably received in a hollow on the inner peripheral side of the first rear end portion,
The fuel injection nozzle according to claim 1, wherein the intermediate chamber is formed between the first main body portion and the second rear end portion. The fuel injection nozzle according to claim 2 or claim 3,
The first fuel flow path and the second fuel flow path are an inter-needle flow path formed by an inner peripheral surface of the first needle and an outer peripheral surface of the second needle, and an outer peripheral side of the first needle. The fuel injection nozzle is always in communication with the first needle through passage provided so as to communicate with the inner peripheral side of the first needle. A fuel injection device comprising the fuel injection nozzle according to claim 2,
A second back pressure operating mechanism for increasing or decreasing the pressure of the fuel in the second back pressure chamber;
Control means for instructing the second back pressure operating mechanism to lift the second needle in the opening direction when a period of time during which fuel is injected only from the first nozzle hole is longer than a predetermined time; A fuel injection device comprising: A fuel injection device comprising the fuel injection nozzle according to claim 3.
An intermediate pressure operating mechanism for increasing or decreasing the pressure of the fuel in the intermediate chamber;
Control means for instructing the intermediate pressure operating mechanism to lift the second needle in an opening direction when a period of time during which fuel is injected from only the first injection hole becomes longer than a predetermined time. A fuel injection device characterized by the above. An injector comprising the fuel injection nozzle according to claim 2,
A first back pressure operating mechanism for increasing or decreasing the fuel pressure in the first back pressure chamber;
A second back pressure operating mechanism for increasing or decreasing the pressure of the fuel in the second back pressure chamber,
The injector, wherein the first back pressure operation mechanism and the second back pressure operation mechanism are arranged in series in the axial direction. An injector comprising the fuel injection nozzle according to claim 2,
A first back pressure operating mechanism for increasing or decreasing the fuel pressure in the first back pressure chamber;
A second back pressure operating mechanism for increasing or decreasing the pressure of the fuel in the second back pressure chamber,
The injector, wherein the first back pressure operation mechanism and the second back pressure operation mechanism are arranged in parallel in the axial direction. Injector according to claim 10,
The first back pressure operating mechanism includes: a first valve body that opens and closes an outlet of the first back pressure chamber; and the first valve body in a direction that opens the outlet of the first back pressure chamber when energized. A first solenoid coil that displaces
The second back pressure operating mechanism includes a second valve body that opens and closes the outlet of the second back pressure chamber, and the second valve body in a direction that opens the outlet of the second back pressure chamber when energized. A second solenoid coil that displaces
The injector, wherein the first solenoid coil and the second solenoid coil have an elliptical cross-sectional shape in the axial direction. An injector comprising the fuel injection nozzle according to claim 2,
A first valve body that opens and closes an outlet of the first back pressure chamber; and a first solenoid coil that displaces the first valve body in a direction to open the outlet of the first back pressure chamber when energized. A first back pressure operating mechanism for increasing or decreasing the fuel pressure in the first back pressure chamber;
A second valve body that opens and closes the outlet of the second back pressure chamber; and a second solenoid coil that is energized to displace the second valve body in a direction to open the outlet of the second back pressure chamber. And a second back pressure operating mechanism for increasing or decreasing the fuel pressure in the second back pressure chamber,
One of the first valve body and the second valve body is provided in a cylindrical shape, and the other valve body is slidably disposed on the inner periphery of the one valve body. Injector. Injector according to claim 12,
Of the first solenoid coil and the second solenoid coil, one solenoid coil for displacing the one valve body is disposed on the tip side of the other solenoid coil for displacing the other valve body. An injector characterized by that.

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