JPS627968A - Fuel injection valve of internal-combustion engine - Google Patents

Abstract

PURPOSE:To reduce power consumption by slidably installing a pressure receiving piston which is operated by the fuel pressure in a pressurization chamber formed in the body of a fuel injection valve, and by controlling a slide valve with a small-sized piezo element. CONSTITUTION:A pressurization chamber 41 is formed in the body of a fuel injection valve 20. A pressure receiving piston 29 operated by the fuel pressure in this chamber 41 is arranged slidably to push a needle 28 in the direction of valve closing. A slide valve 36 is installed, whereby the pressurization chamber 41 can be coupled with either a high-pressure fuel passage 24 or a fuel exhaust chamber 44 selectively. This slide valve 36 is controlled with a piezo element 49. Thus use of a small-sized piezo element is made practicable to assure reduced consumption of the power.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a fuel injection valve for an internal combustion engine.

[Conventional technology]

In internal combustion engines, especially diesel engines, a fuel injection valve using a piezoelectric element is known to perform 4.1 fuel injection control with good responsiveness.
(See Publication No. 0 or Japanese Unexamined Patent Publication No. 1369/1983).

When a voltage is applied to a piezoelectric element, it expands in the axial direction,
The time from applying voltage to stretching is 50 μsec
Since it is an extremely short time of 100 μsec from 100 μsec, responsive fuel injection control becomes possible by utilizing the elongation effect of the piezoelectric element. Therefore, JP-A-60-1725
In the fuel injection valve described in Publication No. 0, the fuel pressure of high-pressure fuel acting on the pressure receiving surface of the needle 1' is increased by the expansion action of the piezoelectric element to open the needle, thereby injecting fuel. ing. On the other hand, JP-A-60-1
In the fuel injection valve described in Publication No. 369, the fuel pressure of high-pressure fuel is applied to the end face of the needle on the opposite side from the nozzle hole, and the fuel pressure of the high-pressure fuel acting on the end face of the needle is reduced by the contraction action of the piezoelectric element. 2) The needle is opened, thereby injecting fuel.

[Problem that the invention seeks to solve]

By the way, in these fuel injection valves, high fuel pressure is applied to the pressure receiving surface of the needle to apply a force in the valve opening direction to the needle, and high pressure fuel pressure is applied to the needle end face to apply a force in the valve closing direction to the needle. The needle is held in the closed state by the difference in force acting on the needle pressure receiving surface and the needle end surface without using a spring that biases the needle in the valve closing direction. However, if an attempt is made to keep the needle closed by the fuel pressure acting on the needle pressure-receiving surface and the needle end face, the force urging the needle in the valve-closing direction will weaken when the fuel pressure becomes low, and the fuel will flow into the nozzle. There is a problem of leakage from the holes.

In addition, these fuel injection valves have a structure in which high fuel pressure acts directly on the piezoelectric element, so a large piezoelectric element is required to withstand the high fuel pressure, resulting in a reduction in power consumption. There is a problem in that the amount increases.

In addition, in the fuel injection valve described in Japanese Patent Application Laid-Open No. 60-1369, the injection valve is inserted into the needle end face -1 through the gap around the needle.
The needle is opened by introducing high-pressure fuel to - and temporarily lowering the pressure of this high-pressure fuel H. However, when the fuel pressure becomes high, as soon as the fuel pressure acting on the needle end face 1- is reduced, the high pressure fuel is guided onto the needle end face through the gap around the needle, so that the needle opens immediately after the valve is opened. There is a problem in that when the valve is closed and the fuel actually becomes under high pressure, fuel injection control cannot be performed.

[Means for solving problems]

In order to solve the above problems, according to the present invention, in a fuel injection valve in which a needle biased by a spring in the valve closing direction has a pressure receiving surface that receives fuel pressure in the needle valve opening direction, pressure is applied within the fuel injection valve body. A pressure receiving piston that forms a chamber and is actuated by the fuel pressure in the pressurizing chamber is slidably disposed, and the pressure receiving piston presses the needle in the valve closing direction, thereby filling the pressurizing chamber within the fuel injection valve body with high pressure fuel i11. A slide valve that can be selectively connected to either the passage or the fuel discharge passage is arranged, and the sliding of the slide valve is controlled by a piezoelectric element.

〔Example〕

Referring to Figures 2 and 3, 1 is the diesel engine body, 2 is the cylinder block, 3 is the cylinder head, and 4 is the cylinder block.
is a piston, 5 is a combustion chamber, 6 is an intake valve, 7 is an exhaust valve, 8
Reference numeral 9 indicates a fuel injection valve disposed within the combustion chamber 5, and 9 indicates an intake manifold.

The fuel injection valve 8 is connected via a fuel supply pipe 10 to a fuel pressure accumulation pipe 11 common to each cylinder. The fuel accumulator pipe 11 has a pressure accumulator chamber 12 with a constant volume inside thereof, and the fuel in this pressure accumulator chamber 12 is supplied to the fuel injection valve 8 via the fuel supply pipe 10. On the other hand, the pressure accumulation chamber 12 is connected via a fuel supply pipe 13 to a discharge port of a fuel supply pump 14 whose discharge pressure can be controlled.

A suction port of the fuel supply pump 14 is connected to a discharge port of a fuel pump 15, and a suction port of the fuel pump 15 is connected to a fuel reservoir tank 16. Each fuel injection valve 8 is also connected to a fuel reservoir tank 16 via a fuel return conduit 17 . The fuel pump 15 is the fuel tank 16
If fuel can be sucked into the fuel supply pump 14 without the fuel pump 15, there is no need to provide the fuel pump 15. . On the other hand, the fuel supply pump 14 is provided to discharge high-pressure fuel, and the high-pressure fuel discharged from the fuel supply pump 14 is accumulated in the pressure accumulation chamber 12.

FIG. 1 shows a side sectional view of the fuel injection valve 8. Referring to FIG. 1, 20 is the fuel injection valve body, 21 is the nozzle, and 22
23 is a spacer, 23 is a nozzle holder for fixing the nozzle 21 and spacer 22 to the fuel injection valve body 20, and 24 is a nozzle holder.
2 indicates a high-pressure fuel inlet, and 25 indicates a nozzle hole formed at the tip of the nozzle 23, respectively. A control rod 26, a pressure bottle 27, and a needle 28, which are arranged in series with each other, are slidably inserted into the fuel injection valve body 20, spacer 22, and nozzle 2. Further, a pressure receiving piston 29 is slidably inserted into the fuel injection valve body 20, and this pressure receiving piston 2
9 is attached to the upper end of the control rod 26. The needle 28 has a conical pressure receiving surface 30.
A needle pressurizing chamber 31 is formed around the needle pressurizing chamber 31 . The needle pressurizing chamber 31 is connected on the one hand to the high pressure fuel inlet 24 via the high pressure fuel 1111 passage 32 and on the other hand to the nozzle hole 25 via an annular fuel passage 33 formed around the needle 28. . A compression spring 34 is inserted into the fuel injection valve main body 20 and urges the pressure pin 27 downward.
The needle 28 is pressed downward by this compression spring 34. On the other hand, a cylindrical hole 35 is formed in the fuel injection valve main body l above the pressure receiving piston 29, and a hollow cylindrical slide valve 36 is slidably inserted into the cylindrical hole 35. The slide valve 36 has a large-diameter valve portion 37 at its lower end, and a circumferential groove 38 is formed above the valve portion 37. Circumference 'a3
The upper wall surface 39 and the upper wall surface 40 forming the numeral 8 are formed in a conical shape. Large diameter valve part 37 of slide valve 36 and pressure receiving piston 2
A pressurizing chamber 41 is formed between the large diameter valve portion 37 and the pressure receiving piston 29, and a compression spring 42 is inserted between the large diameter valve portion 37 and the pressure receiving piston 29. Sliding valve 3
A shaft hole 43 is formed inside the fuel tank 6 , and this shaft hole 43 is connected to a fuel discharge chamber 44 . The fuel discharge chamber 44 is connected to the fuel reservoir tank 16 via a fuel discharge passage 44a and a fuel return conduit 17 (FIG. 2). Shaft hole 4 of sliding valve 36
A check valve 45 is disposed at the upper end opening of 3.

As shown in FIG. 1, a pressurization control device 46 is fixed to the -L end of the fuel injection valve main body 20. A hydraulic piston 47 is slidably inserted into the housing 46a of the pressurization control device Y46, and a pressurization chamber 47a is formed below the hydraulic piston 47. Furthermore, a control piston 48 is slidably inserted into the casing 46a in series with the hydraulic piston 47. The upper end of the control piston 48 has a pressurizing chamber 47.
The lower end of the control piston 48 projects into the fuel discharge chamber 44 and abuts against the check valve 45 .

A piezoelectric element 49 is inserted between the hydraulic piston 47 and the casing 46a. This piezoelectric element 49 has a laminated structure in which a large number of thin plate-shaped piezoelectric elements are laminated.
When a voltage is applied to the piezoelectric element 49, the piezoelectric element 49 causes strain in the longitudinal direction due to an electrostrictive effect, that is, it stretches in the longitudinal direction. Although the amount of elongation is a small amount, for example, about 50 μm, the response is extremely good, and the response time from application of voltage to elongation is about 80 μsec.

When the voltage application is stopped, the piezoelectric element 49 immediately contracts.

When a voltage is applied to the piezoelectric element 49, the piezoelectric element 49 expands, causing the hydraulic piston 47 to descend, and as a result, the fuel pressure in the pressurizing chamber 47a increases. Pressurized chamber 47a
When the fuel pressure within increases, the control piston 48 descends, thereby pushing down the sliding valve 36 via the check valve 45. As a result, the large diameter valve portion 37 of the slide valve 36 separates from the valve seat 35a formed at the lower end of the cylindrical hole 35. Sliding valve 36
The circumferential groove 38 formed in is connected to the high pressure fuel inlet 24 i1
Therefore, when the large-diameter valve portion 37 separates from the valve seat 135a, high-pressure fuel is supplied into the pressurizing chamber 41.

As a result, high fuel pressure acts on the pressure receiving piston 29, so that the needle 28 is maintained in a closed state. The response at this time is extremely fast, about 80 μsec, as mentioned above.

On the other hand, when the voltage application to the piezoelectric element 49 is stopped, the piezoelectric element 49 contracts, and as a result, the pressure chamber 4
The fuel pressure in 7a decreases. When the fuel pressure in the pressurizing chamber 47a decreases, the slide valve 36 rises by 1" due to the fuel pressure in the pressurizing chamber 41 and the spring force of the compression spring 42, and the enlarged valve portion 37 of the slide valve 36 moves upward. 35a, communication between the pressurizing chamber 41 and the high-pressure fuel inlet 24 is cut off. (As will be described later, the large-diameter valve portion 37 may be opened once and then closed.) Next, the reverse one-tooth valve 45 is opened, and the pressurizing chamber 4
1 is discharged into the fuel discharge chamber 44. As a result, the fuel pressure in the pressurizing chamber 41 decreases 7, and the downward force acting on the pressure receiving piston 29 decreases by (lO). As a result, the needle 28 opens and fuel injection begins. The response at this time is also extremely fast, approximately 8077 seconds.

As shown in FIG. 1, when the large-diameter valve portion 37 of the slide valve 36 is seated on the valve seat 35a, the conical shape of the circumferential groove 38 exposed within the circumferential groove 38 of the slide valve 36 is The areas of the lower wall surface 39 and the conical lower wall surface 40 are equal, so that the circumferential groove 3
The high pressure fuel during the day exerts an axial force on the sliding valve 36.
stomach. Therefore, the slide valve 36 can be lowered with a small force, and thus the slide valve 36 can be controlled by the small piezoelectric element 49. Note that once high pressure is applied in the pressurizing chamber 41, the large-diameter valve body 37 may be seated on the valve seat 35a, and therefore the piezoelectric element 49 simply closes the reverse 11-valve 45. Reverse the power of IL
It is sufficient if it is applied to the valve 45. Therefore, a small piezoelectric element 49 is sufficient, and therefore, a small electric power is sufficient to be applied to the piezoelectric element 49.

FIGS. 4 and 5 show an example of a fuel supply pump 14 whose discharge pressure can be controlled. Referring to FIG. 4, the fuel supply pump 14 has a fixed shaft 51 that is fixedly supported by the pump casing 50, a rotor 52 that rotates around the fixed shaft 51, and a pivot pin 53 that allows the fuel supply pump 14 to be attached to the pump casing 50 in a swingable manner. a stator 54 attached thereto, and a ring 56 rotatably supported within the stator 54 via a bearing 55.
and has. The rotor 52 includes a large number of radial pistons 57 arranged radially, and each radial piston 5
A shoe 58 that rotates together with the radial piston 57 is inserted between the ring 56 and the radial piston 57 . When the rotor 52 rotates, the radial piston 57 also rotates, and at this time, the shoe 58 slides on the inner peripheral surface of the ring 56, and the ring 56 also rotates due to the frictional force with the shoe 58.

A suction port 59 and a discharge port 17160 are formed in the fixed shaft 51, and the suction port 59 is connected to the fuel pump 15 (FIG. 2), and the discharge port 60 is connected to the pressure accumulation chamber 12 (FIG. 2). The cylinder chambers 61 of each radial cylinder 57 alternately communicate with the suction port 59 and the discharge port 60.

When the cylinder chamber 61 communicates with the suction port 59, the radial piston 57 moves radially outward, so fuel is sucked into the cylinder chamber 61, and the cylinder chamber 61 communicates with the discharge port 59.
0, compressed fuel is discharged from the cylinder chamber 61 to the discharge port 60. The pressure of the fuel discharged to the discharge port 60 depends on the stroke of the radial piston 57, and the stroke of the radial piston 57 is determined by the position of the stator 54. Therefore, by swinging the stator 54 around the pivot pin 53, the discharge pressure of the fuel supply pump 14 can be controlled.

Referring to FIGS. 4 and 5, pump casing 50
A control lever 62 that is slidable in the axial direction of the fixed shaft 51 is arranged at the bottom of the fixed shaft 51 . The control lever 62 has a long groove 63 inclined with respect to the axis of the control lever 62, and an arm 64 formed at the lower part of the stator 54 is slidably inserted into the long groove 63. Therefore, when the control lever 62 is moved in its axial direction, the stator 54 swings, thereby controlling the discharge pressure of the fuel supply pump 14.

The control lever 62 is connected to a drive device 66 via a speed reduction mechanism 65. In this embodiment, the drive device 66 is formed of a step motor, but it is not necessary to use a step motor; for example, a linear solenoid or other means can be used as the drive device 66. Drive bag M66
As a result, the control lever 62 is moved in its axial direction, so that the discharge pressure of the fuel supply pump 14 is controlled by the drive device 66.

Referring again to FIG. 2, the fuel injection valve 8 and the drive bag f
An electronic control unit 70 is provided for controlling f66. This electronic control system) 70 consists of a digital computer, and includes a ROM (read-on memory) 72, a RAM (random access memory) 73, a CPtJ (microprocessor) 74, an input port door 5 and An output port door 6 is provided.

As shown in FIG. 2, a fuel pressure sensor 80 for detecting the fuel pressure within the pressure accumulation chamber 12 is attached to the end of the fuel pressure accumulation pipe 11. The fuel pressure sensor 80 generates an output voltage proportional to the fuel pressure in the pressure accumulator 12, and this fuel pressure sensor 80
It is connected to the input port door 5 via a converter 81 . On the other hand, a supercharging pressure sensor 82 is installed inside the intake manifold 9 to detect the supercharging pressure within the intake manifold 9. A boost pressure sensor 82 generates an output voltage proportional to the pressure in the intake manifold 9, and is connected to the manual port door 5 via an Ar'1 converter 83.

Further, a water temperature sensor 84 is attached to the engine body 1 to detect engine cooling water lXl. The water temperature sensor 84 generates an output voltage proportional to the engine cooling water temperature.
is connected to the input port door 5 via an AD converter 85. Further, the accelerator pedal 86 has a load sensor 87 which generates an output voltage proportional to the degree to which the accelerator pedal 86 is depressed.
is installed. This load sensor 87 is an AD converter 88
It is connected to the input port door 5 via. Further, a pair of disks 89 and 90 are attached to the engine crankshaft, and a pair of crank angle sensors 91 and 92 are arranged opposite the toothed outer peripheral surfaces of these disks 89 and 90. One crank angle sensor 91 generates an output pulse indicating, for example, that the No. 1 cylinder is at the intake-1-dead center, and therefore, the fuel injection valve 8 of any cylinder is actuated from the output pulse of this crank angle sensor 91. can be determined. The other crank angle sensor 92 generates an output pulse every time the crankshaft rotates by a certain angle, so the engine speed can be calculated from the output pulse of the crank angle sensor 92. These crank angle sensors 9
1°92 is connected to the manual port door 5. On the other hand, the output port door 6 is connected via a drive circuit 93 to a drive device 66 consisting of a step motor, and is connected via a drive circuit 94 to a piezoelectric element 40 of a corresponding fuel injection valve 8.

Next, the operation of the fuel injection control device according to the present invention will be explained with reference to FIGS. 6 to 10.

FIG. 6 shows the main routine, which is executed by interrupts at every fixed crank angle. Referring to FIG. 6, first, in step 100, the output signal of the crank angle sensor 92 representing the engine speed N, the output signal of the load sensor 87 representing the amount of depression I7 of the accelerator pedal, and the overcharging pressure B indicating no overflow. Supply pressure sensor 82
, the output signal of the water temperature sensor 84 representing the engine cooling water temperature T, and the output signal of the fuel pressure sensor 80 representing the fuel pressure P in the pressure accumulator 12 are sequentially input into the CPll 74, and the output signal of the crank angle sensor 92 is input into the CPll 74. Engine speed N is calculated from the output signal. These engine speed N, accelerator pedal depression 14, boost pressure B, water temperature T and fuel pressure P
is stored in RAM 73. Then step 200
In step 300, the injection amount τ is calculated, in step 300, the injection timing is calculated, and in step 400, the fuel pressure P is controlled. The calculation of the injection amount τ in step 200 is shown in FIG. 7, the calculation of the injection timing in step 300 is shown in FIG. 8, and the control of the fuel pressure P in step 400 is shown in FIG.

FIG. 7 shows a flowchart for calculating the fuel injection amount τ. Referring to Figure 7, first step 20
1, the amount of depression of the accelerator pedal, that is, the basic fuel injection amount τ from the load ■5. is counted as 1. Fig. 10 (al indicates the relationship between the basic fuel injection amount τ and the load 1-,
This relationship is stored in the ROM 72 in advance. Next, in step 202, a supercharging correction coefficient of 1 is calculated from the supercharging pressure P. As shown in Fig. 10 (bl), the boost pressure correction coefficient 1 increases as the boost pressure P increases.
The relationship shown in FIG. 0 fbl is stored in the ROM 72 in advance. Next, in step 203, the injection amount τ- is increased by 1.
τ. is calculated. Next, in step 204, the maximum injection amount MAX is calculated from the water temperature T. As shown in FIG. 10 fcl, in order to prevent the generation of white smoke, the maximum injection amount MAX becomes smaller as the water temperature T becomes higher. Next, in step 205, it is determined whether the injection amount τ is larger than the maximum injection amount MAX. If τ〉gate^X, step 206
Then, τ=MAX. Therefore, the maximum injection amount MA
X will be limited by the water temperature T.

FIG. 8 shows a flowchart for calculating the fuel injection period. Referring to FIG. 8, first step 30
1, the injection start timing τ is determined from the engine speed N and the load I.
is calculated. As shown in FIG. 10 (+1), the relationship between the injection start timing τ14,...τ and the engine speed N1 load is stored in advance in the ROM 72 in the form of a map, and the injection is started from this map. A time τ1 is calculated. Next, in step 302, a water temperature correction coefficient of 2 is calculated from the water temperature T. The water temperature correction coefficient 2 becomes smaller as the water temperature increases by 1, as shown in Figure 10 f and fl, and Figure 10 (
The relationship shown in ) is stored in advance in the ll0M 72.Next, in step 303, a supercharging correction coefficient of 3 is calculated from the supercharging pressure P.The supercharging pressure correction coefficient of 3 is
As shown in e), the boost pressure increases as the boost pressure P increases, and the relationship shown in FIG. 10 (8) is stored in the ROM 72 in advance.

Next, in step 304, a correction coefficient of 2. 3 is added to the actual injection start timing τ. The actual injection start timing τ8 increases, that is, becomes faster as 2+3 increases. Next, in step 305, the injection completion time τ5 is calculated from the injection amount τ calculated by 1 in the routine shown in FIG. 7 and the actual injection start time τ3. The injection start time τ obtained in this way
3 and injection completion time τ are outputted to the output port door 6 in step 306, and these τ3. Injection control of each fuel injection valve 8 is performed according to τ.

FIG. 9 shows a flowchart for controlling the fuel pressure P. Referring to Figure 9, first step 40
1, the reference fuel pressure P0 is determined from the engine speed N and the load l.
is calculated. As shown in Fig. 10 (gl), the relationship between the reference fuel pressure P, ... Pl, engine speed N, and load is stored in advance in the ROM ?2 in the form of a map, and from this map Fuel pressure P0 is calculated.Next, in step 402, a water temperature correction coefficient of 4 is calculated from the water temperature T.The water temperature correction coefficient of 4 increases as the water temperature T increases, as shown in FIG. The relationship shown in FIG. fl) is stored in advance in the ROM 72. Next, in step 403, a boost pressure correction coefficient of 5 is calculated from the boost pressure P. The boost pressure correction coefficient 5 increases as the boost pressure P increases, as shown in Figure 10+11, and the first
The relationship shown in FIG. 0 fh) is stored in the ROM 72 in advance. Next, in step 404, the reference fuel pressure P determined in step 401 is determined. to the correction coefficient 4. The target reference fuel pressure is determined by multiplying by 5 (■). , that is, the target fuel pressure P0 is determined. This target fuel pressure P0 becomes larger as the water temperature T becomes higher, and becomes larger as the boost pressure P becomes higher. Next, in step 405, the target fuel pressure P is determined. It is determined whether the absolute value of the difference between the current fuel pressure P and the current fuel pressure P is smaller than ΔP.

When l'po-pl≧ΔP, the process proceeds to step 406, where it is determined whether p>po. p＞'p.

In this case, the process proceeds to step 407, where a predetermined number of steps A is subtracted from the step position ff5T of the drive device 66, that is, the step motor 66. As a result, the control lever 62 (FIGS. 4 and 5) of the fuel supply pump 14
Since the fuel pressure in the pressure accumulator chamber 12 is moved in the direction of decreasing the discharge pressure of the fuel, the fuel pressure in the pressure accumulator chamber 12 immediately decreases. On the other hand, P≦P,
In this case, the process proceeds to step 408, where a fixed number of steps A is added to the step position MST of the step motor 66. As a result, the control lever 62 of the fuel supply pump 14 is moved in the direction of increasing the discharge pressure of the fuel supply pump 14, so that the fuel pressure within the pressure accumulation chamber 12 immediately increases. On the other hand, in step 405 lp.

When it is determined that -PI<ΔP, the processing routine is completed, and the step motor 66 is held stationary at this time. In this way, the fuel pressure P in the pressure accumulator 12 reaches the target fuel pressure P. will be maintained.

〔Effect of the invention〕

The fuel pressure does not directly act on the piezoelectric element, and the needle closes when the fuel pressure in the pressurizing chamber of the hydraulic piston is slightly increased, allowing the use of a small piezoelectric element and reducing power consumption. can be reduced.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of the fuel injection valve, Fig. 2 is a plan view schematically showing the diesel engine, Fig. 3 is a side sectional view of the diesel engine, Fig. 4 is a side sectional view of the fuel supply pump,
FIG. 5 is a plan view of the control lever and its drive device shown in FIG. 4, FIG. 6 is a flowchart showing the main routine, and FIG.
, FIG. 8 is a flowchart for calculating the injection period, FIG. 9 is a 71 coach yard for controlling fuel pressure, and FIG. 10 is a diagram showing correction coefficients, etc. 8...Fuel injection valve, 26...Control rod, 2
8... Needle, 29... Pressure receiving piston, 3
6...Sliding valve, 41...Pressure chamber, 44...
Fuel discharge chamber, 47... Hydraulic piston, 49...
Piezoelectric element. μ-Fuel discharge chamber 47---Hydraulic piston/49---Piezoelectric element Fig. 1 Fig. 4 (a) l) L
P(d)
(e) (g) (h
) (C) ■ (f) ■ (尤) Figure 10 1 -1 'J A -

Claims (1)

[Claims] In a fuel injection valve having a pressure-receiving surface where the needle is spring-biased in the valve-closing direction and receives fuel pressure in the needle-opening direction, a pressurized chamber is formed in the fuel injector body, and the fuel pressure in the pressurized chamber is A pressure receiving piston to be operated is slidably disposed, the pressure receiving piston pushes the needle in the valve closing direction, and the pressurized chamber is connected to either the high pressure fuel passage or the fuel discharge passage within the fuel injection valve body. A fuel injection valve for an internal combustion engine, in which a selectively connectable sliding valve is arranged and the sliding of the sliding valve is controlled by a piezoelectric element.