JP2000002356A - Solenoid valve and fuel injection valve using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solenoid valve whose valve member chokes a fluid passage certainly and also a fuel injection valve using such a solenoid valve, in which the sliding surfaces of the valve member and a piston member are precluded from eccentric wear even if members involve a processing tolerance or installing tolerance. SOLUTION: A gap 65 is formed between the peripheral wall of a valve member 31 of a solenoid valve 30 and the inside wall of a valve body 33. A balance piston 32 supports the valve member 31 slidably relative to the valve member 31. The balance piston 32 is provided with a spherical recess 32a positioned opposite a control pressure chamber 40, and this spherical surface of the recess 32a is slidable with a convex spherical surface of a sphere member 38. Even if members involve a processing tolerance or installing tolerance, eventual tolerance can be eliminated by allowing the balance piston 32 to tilt in sliding with respect to the sphere member 38.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve, and more particularly to a solenoid valve used as a fuel injection valve of an internal combustion engine (hereinafter, "internal combustion engine" is referred to as an engine).

[0002]

2. Description of the Related Art Conventionally, in a fuel injection valve used in a pressure-accumulation type fuel injection device, a control pressure chamber is disposed on a side opposite to an injection hole of a movable member including a needle valve, and the fuel pressure in the control pressure chamber is reduced. It is known that the fuel injection amount and the fuel injection timing are adjusted by controlling with an electromagnetic valve.

FIG. 5 shows an example of such a fuel injection valve. Fuel supplied from a common rail (not shown) to the fuel injection valve 100 is supplied from a fuel passage 101 to a fuel reservoir 104 around a needle valve 103 through a fuel passage 102.

The fuel branched from the fuel passage 101 to the fuel passage 105 is supplied from an inflow restrictor 106 to a control pressure chamber 108 formed on the control piston 107 on the side opposite to the injection hole. Outflow restrictor 110 is in communication with control pressure chamber 108.

[0005] The cylindrical valve member 120 includes a valve body 121.
And is supported by the valve body 121 in a reciprocating manner. The valve member 120 is moved by the spring 124 to the valve body 1.
21 is urged by a valve seat 121a. The balance piston 122 is disposed in the valve member 120 and slides with the valve member 120. The balance piston 122 is pressed by the stopper member 123 by the fuel pressure in the control pressure chamber 108 and is locked by the stopper member 123. When energization of the solenoid 125 is turned on, the valve member 120
21a. Then, the outflow restriction 110 communicates with the fuel discharge passage 111, and the high-pressure fuel in the control pressure chamber 108 is discharged from the fuel injection valve 100 through the fuel discharge passages 111, 112, and 113. Then, the fuel pressure in the control pressure chamber 108 decreases, the needle valve 103 lifts, and fuel is injected from an injection hole (not shown) formed in the valve body 114.

[0006] In the fuel injection valve having the structure shown in FIG.
It is necessary to machine the inner peripheral wall of the valve member 120 and the outer peripheral wall of the balance piston 122 with high precision so that fuel does not leak from the sliding portion between the valve member 120 and the balance piston 122.

However, for example, as shown in FIG. 6, the end face 1 of the balance piston 122 on the opposite side to the valve seat 121a is provided.
When a machining tolerance or an assembly tolerance occurs between the end 22a and the end surface 123a of the stopper member 123, the balance piston 122 receives a force in a direction in which the shaft 131 of the balance piston 122 is inclined with respect to the shaft 130 of the fuel injection valve 100. Then, the balance piston 122, the valve member 120, and the valve member 12
There is a possibility that a biased force is applied to the sliding surface at a sliding position between the valve body 121 and the valve body 121, and the sliding surface may be unevenly worn. If the sliding portion of each member wears unevenly, fuel may leak from the sliding portion.

When a gap larger than the sliding clearance is formed between the valve member 120 and the valve body 121, the valve member 120, the balance piston 122, or the stopper member 123 has processing tolerances or assembling tolerances. When the member 120 is tilted together with the balance piston 122 as shown in FIG. 6, a gap is generated between the valve member 120 and the valve seat 121a in a state where the valve member 120 is seated on the valve seat 121a, and fuel leaks from the control pressure chamber 108. , Control pressure chamber 108
Pressure drops. Then, the force for urging the needle valve 103 in the injection hole closing direction is reduced, so that the needle valve 10
3 may be lifted and fuel may be injected at times other than the predetermined timing.

If the urging force of the spring 124 is increased, the valve member 120 moves while sliding on the valve seat 121a after the valve member 120 is seated on the valve seat 121a.
20 and the valve seat 121a, and the control pressure chamber 108
Can prevent fuel leakage.

However, since the valve member 120 slides on the valve seat 121a due to the large urging force of the spring 124, the sliding portion between the valve member 120 and the valve seat 121a is unevenly worn, and the valve member 120 is attached to the valve seat 121a. Control pressure chamber 10 even when seated
8 leaks fuel, and the pressure in the control pressure chamber 108 decreases. Then, since the force for urging the needle valve 103 in the injection hole closing direction is reduced, the needle valve 103 may be lifted and fuel may be injected at a timing other than the predetermined timing.

[0011]

Problems to be Solved by the Invention
In the fuel injection valve disclosed in Japanese Unexamined Patent Publication (Kokai) No. 1 (Kokai) No. 1-2003, there is disclosed a fuel injection valve in which the end of a plunger as a balance piston abutting on a stopper is formed in a spherical shape. However, since the valve member is configured to be slidably supported in the valve body, it is difficult for the plunger to swing even if the plunger is swingable with respect to the stopper. Therefore, when processing tolerance or assembly tolerance of each member occurs,
A biased force is applied to the sliding surface at the sliding portion between the valve member and the valve body, and between the valve member and the plunger, and the sliding surface may be unevenly worn. Further, if a gap is formed between the abutting portion of the valve member and the valve seat in a state where the valve member is seated on the valve seat, fuel cannot be moved from the control pressure chamber because the valve member cannot move even if the gap is filled. Leak.

An object of the present invention is to prevent a biased force from being applied to a sliding surface between a valve member and a piston member even if each member has a processing tolerance or an assembly tolerance, and the sliding surface has an uneven wear. To prevent It is still another object of the present invention to provide an electromagnetic valve that reliably closes a fluid passage when the valve member is seated on a valve seat, and a fuel injection valve using the same.

[0013]

According to the solenoid valve according to the first aspect of the present invention, a gap is formed between the valve member and the valve body, and the piston member is locked in the stopper member. It is swingable with respect to the stopper member. Therefore, even if there is a processing tolerance or an assembly tolerance in the piston member or the stopper member, the piston member swings with respect to the stopper member so as to eliminate the tolerance, and the position of the valve member shifts as the piston member swings. Since a biased force is not applied to each sliding surface of the valve member and the piston member, uneven sliding of the sliding surface between the valve member and the piston member can be prevented, and fluid can be prevented from leaking from the sliding portion. Further, the valve member and the piston member can slide smoothly.

Further, since the valve member can be shifted in position and seated on the valve seat by moving together with the piston member, even if the valve member, the piston member or the stopper member has a processing tolerance or an assembly tolerance, the valve member is not allowed to have a clearance. Can be seated on the valve seat without forming the valve seat. Therefore, the fluid passage can be reliably closed in a state where the valve member is seated on the valve seat.

According to the solenoid valve of the second aspect of the present invention,
A gap is formed between the valve member and the valve body, and the piston member and the stopper member can slide on the concave spherical surface and the convex spherical surface while the piston member is locked by the stopper member. Therefore, even if there is a processing tolerance or an assembly tolerance in the piston member or the stopper member, the piston member slides with respect to the stopper member so as to eliminate the tolerance, and the position of the valve member shifts with the sliding of the piston member. Since a biased force is not applied to each sliding surface of the valve member and the piston member, uneven sliding of the sliding surface between the valve member and the piston member can be prevented, and fluid can be prevented from leaking from the sliding portion. Further, the valve member and the piston member can slide smoothly.

Further, since the valve member can be shifted in position and seated on the valve seat by moving together with the piston member,
Even if the valve member, the piston member or the stopper member has a processing tolerance or an assembly tolerance, the valve member can be seated on the valve seat without forming a gap. Therefore, the fluid passage can be reliably closed in a state where the valve member is seated on the valve seat.

According to the solenoid valve of the third aspect of the present invention,
The inside diameter of the valve member is formed to be substantially the same diameter, the contact portion of the valve member seated on the valve seat is formed in a tapered shape, and the inside diameter of the valve member is substantially equal to the seat diameter of the valve member. Therefore, even if the valve member has a processing tolerance, the valve member does not receive a force from the surrounding fluid of the valve member in the reciprocating direction in a state where the valve member is seated on the valve seat. Therefore, it is possible to prevent the valve opening pressure for separating the valve member from the valve seat from varying for each solenoid valve.

According to the fuel injection valve of the present invention, a control pressure chamber is provided on the side opposite to the injection hole of the needle valve which opens and closes the injection hole, and the electromagnetic valve according to any one of claims 1, 2 and 3 is used. The fuel pressure in the control pressure chamber is adjusted by intermittently connecting the control pressure chamber and the low fuel pressure side. Therefore,
It is possible to prevent the fuel in the control pressure chamber from leaking in the solenoid valve and reduce the pressure in the control pressure chamber, and prevent the fuel from being injected from the injection hole at any time other than the predetermined timing.

[0019]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a first embodiment of the present invention; (First Embodiment) FIG. 3 shows an example in which a fuel injection valve of a diesel engine according to a first embodiment of the present invention is used in an accumulator type fuel injection device.

The fuel sucked from the fuel tank 2 by the low-pressure pump 1 is pressurized by the high-pressure pump 3 and sent to the common rail 4 as an accumulator by pressure. The metering valve 5 is an electromagnetic valve for adjusting the amount of fuel pumped by the high-pressure pump 3. Engine 7
Is a six-cylinder diesel engine, and a fuel injection valve 10 is attached to each cylinder. The solenoid valve 30 is a solenoid valve that adjusts the fuel injection timing and the fuel injection amount of the fuel injection valve 10. The high-pressure fuel accumulated at a constant pressure by the common rail 4 is supplied to the fuel injection valve 10, and the fuel is injected from the fuel injection valve 10 into each cylinder of the engine 7.

An engine control unit (hereinafter referred to as an "ECU") 6 controls a metering valve 5 and a fuel injection valve of the high-pressure pump 3 in accordance with the operation state of the engine based on detection signals sent from the respective sensors. A control signal is sent to the ten electromagnetic valves 30 and the like. The sensor 11 is a sensor for detecting the fuel pressure in the common rail 4 and the sensor 12 is
Is a sensor that detects the water temperature of A sensor (not shown) that detects the amount of depression of the accelerator pedal 13 is also used by the ECU 6.
Is sent out.

Next, the configuration of the fuel injection valve 10 will be described in detail. As shown in FIG. 2, the valve body 20 and the housing 22 are connected by a retaining nut 23 with a distance piece 21 interposed therebetween. A plurality of injection holes (not shown) are formed at the tip of the valve body 20. Movable member 2
Reference numeral 4 is composed of a plurality of members including a needle valve 25 and a control piston 26, and reciprocates to open and close a plurality of injection holes. The valve body 20 is provided with a needle valve seat (not shown) on the upstream side of the injection hole, and the injection hole is closed when the needle valve 25 is seated on the needle valve seat. The spring 27 urges the needle valve 25 downward in FIG. 2, that is, in the nozzle hole closing direction. A control pressure chamber 40 is formed on the side of the control piston 26 opposite the injection hole.

The fuel supplied from the common rail 4 to the periphery of the movable member 24 through the fuel passages 60 and 61 passes through gaps formed between the movable member 24 and the housing 22, the distance piece 21 and the valve body 20. The tip of the needle valve 25 is reached. A chamfer is formed at a position where the movable member 24 except the control piston 26 slides on the housing 22, the distance piece 21, and the valve body 20 so that fuel can pass therethrough.

The fuel supplied to the fuel passage 60 is also supplied from the fuel passage 62 to the control pressure chamber 40 via the inflow restrictor 41a.

The solenoid valve 30 is a two-way solenoid valve, and is disposed above the housing 22. Valve member 3 of solenoid valve 30
1 is reciprocally accommodated in the valve body 33 and can be seated on a valve seat 33a provided in the valve body 33 and shown in FIG. The inner diameter of the valve body 33 is larger than the outer diameter of the valve member 31, and a gap 6 between the outer peripheral wall of the valve member 31 and the inner peripheral wall of the valve body 33 in which the valve member 31 can move in the radial direction.
5 are formed. The valve member 31 is urged toward the valve seat 33a by a spring 37 as urging means.

Balance piston 3 as piston member
Reference numeral 2 is housed in the valve member 31 and supports the valve member 31 so as to be slidable relative to the valve member 31. The concave portion 32a formed on the opposite side of the balance piston 32 from the control pressure chamber 40 has a concave spherical surface, and the spherical member 38 as a stopper member has a convex spherical surface. Balance piston 32
The movement in the opposite direction to the valve seat 33a is restricted by being locked by the spherical member 38. The concave spherical surface of the concave portion 32a is slidable with the convex spherical surface of the spherical member 38. When the engine starts and fuel is supplied to the fuel injection valve 10 from the common rail, the balance piston 32 is pressed via the spherical member 38 by the pressure of the control pressure chamber 40.

The seat diameter d ₁ of the valve member 31 is substantially equal to the inner diameter d ₂ of the valve member 31 sliding on the balance piston 32. That is, FIG. 1 in which the valve member 31 is seated on the valve seat 33a.
In the state shown in (1), the force that the valve member 31 receives from the high-pressure fuel on the control pressure chamber 40 side in the lift direction is substantially equal to the force that the valve member 31 receives from the high-pressure fuel in the valve member 31 in the direction of sitting on the valve seat 33a. Since the fuel pressure acting on the other pressure receiving surface of the valve member 31 is extremely small as compared with the high-pressure fuel in the control pressure chamber 40 and the high-pressure fuel in the valve member 31, the valve member 31 is moved in the opening direction of the electromagnetic valve 30 and It can be considered that the forces received in the valve closing direction are substantially equal. Therefore, the attraction force of the solenoid 34 that attracts the valve member 31 against the urging force of the spring 37 can be reduced, and the size of the entire solenoid valve can be reduced.

The solenoid 34 is wound around a core 35, and a drive pulse is supplied to the solenoid 34 from a pin 51 of a connector 50. The valve member 31 is attracted together with the armature 36 against the urging force of the spring 37 by the magnetic force generated when the power supply to the solenoid 34 is turned on,
The valve member 31 is separated from the valve seat 33a.

The discs 41, 42 are sandwiched between the housing 22 and the valve body 33, and each of the discs 41, 42
a, an outflow restrictor 42a is formed. Control piston 2
The control pressure chamber 40 provided on the side opposite to the injection hole 2 communicates with the fuel passage 62 via the inflow restrictor 41a.

As shown in FIG. 1, the valve member 31 is
When seated at a, the fuel passage from the control pressure chamber 40 to the fuel discharge passage 63 on the low pressure side of the fuel is closed.

When the valve member 31 is separated from the valve seat 33a,
The high-pressure fuel in the control pressure chamber 40 flows out of the outflow restrictor 42a into the fuel discharge passage 63, and is returned from the fuel injection valve 10 to, for example, a fuel tank.

Next, the operation of the fuel injection valve 10 will be described. (1) When the power to the solenoid 34 is turned off, the valve member 31 is seated on the valve seat 33a by the urging force of the spring 37, so that the communication between the control pressure chamber 40 and the fuel discharge passage 63 is cut off. Therefore, no fuel is discharged from the control pressure chamber 40, and the fuel pressure in the control pressure chamber 40 is high. At this time, the force that the movable member 24 receives in the injection hole closing direction from the fuel in the control pressure chamber 40 and the spring 27 is greater than the force that the movable member 24 receives from the fuel around the movable member 24 in the injection hole opening direction. 25 closes the injection hole, and no fuel is injected from the injection hole.

(2) When the power supply to the solenoid 34 is turned on, the armature 36 and the valve member 31 are attracted toward the solenoid 34 against the urging force of the spring 37, and the valve member 31 is separated from the valve seat 33a. Controlled by pressure chamber 4
0 communicates with the fuel discharge passage 63, and the fuel pressure in the control pressure chamber 40 decreases. The pressure in the control pressure chamber 40 decreases, and the force that the movable member valve 24 receives in the injection hole closing direction from the fuel and the spring 27 in the control pressure chamber 40 receives the movable member 24 in the injection hole opening direction from the fuel around the movable member 24. When the force is smaller than the force, the needle valve 25 is lifted, and fuel is injected from the injection hole.

(3) When energization of the solenoid 34 is turned off, the valve member 31 is actuated by the
3a, the communication between the control pressure chamber 40 and the fuel discharge passage 63 is cut off. When the force that the movable member 24 receives in the injection hole closing direction from the fuel in the control pressure chamber 40 and the spring 27 becomes greater than the force that the movable member 24 receives in the injection hole opening direction from the fuel supplied around the movable member 24. The needle valve 25 closes the injection hole, and fuel injection from the injection hole is shut off.

In the first embodiment, the balance piston 32 is slidably engaged with the spherical member 38, and a gap 65 is formed between the outer peripheral wall of the valve member 31 and the inner peripheral wall of the valve body 33. . Therefore, even if there is a processing tolerance or an assembly tolerance in the concave portion 32a of the balance piston 32 or the spherical member 38, the tolerance can be eliminated by sliding and inclining the balance piston 32 with respect to the spherical member 38.

Since a biased force is not applied to the sliding surface at the sliding portion between the valve member 31 and the balance piston 32, the valve member 31 smoothly reciprocates and the sliding surface can be prevented from being unevenly worn. . Therefore, it is possible to prevent fuel from leaking from a sliding portion between the valve member 31 and the balance piston 32 in a state where the valve member 31 is seated on the valve seat 33a,
Since the fuel pressure in the control pressure chamber 40 can be controlled with high accuracy,
It is possible to prevent fuel from being injected from the injection hole at a timing other than the predetermined timing.

Further, even if the valve member 31, the valve seat 33a, the balance piston 32, or the spherical member 38 has a processing tolerance or an assembly tolerance, the tolerance can be absorbed by tilting the valve member 31 together with the balance piston 32. . Therefore, when the power supply to the solenoid 34 is turned off, the valve member 31 is securely seated on the valve seat 33a without forming a gap, and the communication between the control pressure chamber 40 and the low fuel pressure side is interrupted. Fuel can be prevented from being injected.

Further, the valve member 31 is moved by a large force to the valve seat 33.
Since the valve member 31 is not biased to a, even if the valve member 31 slides with the valve seat 33a to correct the seating position, wear of the valve member 31 and the valve seat 33a can be prevented.

In the first embodiment, the fuel is supplied to the injection hole from the fuel passage 60 through the accommodation hole which accommodates the movable member 24 in a reciprocating manner. In other words, there is no need to drill a fuel passage for supplying fuel to the injection hole separately from the accommodation hole that accommodates the movable member 24 in a reciprocating manner. Therefore, the diameter of the injection side of the fuel injection valve can be reduced as compared with the case where the fuel passage is perforated separately from the accommodation hole. Since the housing hole for housing the movable member 24 also serves as a fuel passage for supplying fuel to the injection hole,
Processing man-hours are reduced. Since the volume of the fuel injection valve that accommodates the high-pressure fuel is increased, a decrease in fuel pressure during fuel injection can be reduced, and pulsation generated in fuel in the fuel injection valve can be reduced.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
Shown in Components that are substantially the same as those in the first embodiment are denoted by the same reference numerals.

The valve member 75 is formed in a cylindrical shape and has substantially the same inner diameter d ₃ in the axial direction. The valve member 75 has a tapered contact portion 75a formed by cutting off a conical end. The inner peripheral edge of the contact portion 75a is seated on the disk 42 as a valve seat forming the outflow restrictor 42a. When the seat diameter of the valve member 75 and d _4, d ₃ =
d is _four. When the abutting portion 75a is seated on the disk 42, communication between the control pressure chamber 40 and the fuel discharge passage 77 on the low fuel pressure side is cut off. Since d _{3 is} always d ₄ , even if the valve member 75 has a processing tolerance, the valve member 75 does not receive a force from the fuel in the direction of sitting away from the disk 42 and in the direction of sitting on the disk 42. Therefore, the timing at which the valve member 75 separates from the disk 42 is constant without variation for each fuel injection valve. Thus, it is possible to prevent the fuel injection amount and the fuel injection timing from being injected from the injection hole from being varied for each fuel injection valve.

In the embodiments of the present invention described above, a gap is formed between the outer peripheral wall of the valve member and the inner peripheral wall of the valve body, and the balance piston slides on the spherical member 38 as the stopper member. It is movably locked. Therefore, even if each member has a processing tolerance or an assembly tolerance, the balance piston and the valve member can move so as to eliminate the tolerance. Therefore, since a biased force is not applied to the sliding surface at the sliding position between the valve member and the balance piston,
It is possible to prevent uneven wear of the sliding surface and prevent fuel leakage from the sliding portion. Further, the communication between the control pressure chamber 40 and the low fuel pressure side can be reliably shut off in a state where the valve member is seated on the valve seat. With such a configuration, the fuel pressure in the control pressure chamber 40 can be controlled with high accuracy, so that a desired fuel injection amount and fuel injection timing can be realized. Further, it is possible to prevent the fuel injection amount and the fuel injection timing from varying for each fuel injection valve.

In the above embodiments, the concave spherical surface of the balance piston 32 and the convex spherical surface of the spherical member 38 serving as the stopper member slide. However, the convex spherical surface of the balance piston and the concave spherical surface of the stopper member are used. May slide. Further, as disclosed in, for example, Japanese Patent Application Laid-Open No. 9-178041, a configuration may be employed in which the convex surface of the balance piston abuts against the flat surface of the stopper member, and the balance piston swings with respect to the stopper member. However, when a large load is applied due to an increase in the Hertzian stress in the present embodiment, it is necessary to harden the material of the flat surface.

In the above embodiments, the solenoid valve of the present invention is used to adjust the fuel pressure in the control pressure chamber of the fuel injection valve. It is possible to use a solenoid valve of

[Brief description of the drawings]

FIG. 1 is a sectional view showing an electromagnetic valve portion of a fuel injection valve according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a fuel injection valve according to a first embodiment of the present invention.

FIG. 3 is a configuration diagram illustrating a fuel supply system using a fuel injection valve according to a first embodiment of the present invention.

FIG. 4 is a sectional view showing an electromagnetic valve portion of a fuel injection valve according to a second embodiment of the present invention.

FIG. 5A is a cross-sectional view illustrating a fuel injection valve according to a conventional example, and FIG. 5B is a cross-sectional view illustrating a solenoid valve portion of FIG.

FIG. 6 is a schematic sectional view showing the inclination of a valve member in a conventional solenoid valve.

[Explanation of symbols]

 Reference Signs List 10 fuel injection valve 25 needle valve 30 solenoid valve 31 valve member 32 balance piston 33 valve body 33a valve seat 34 solenoid 37 spring (biasing means) 38 spherical member (stopper member) 75 valve member 76 valve body

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshio Kondo 1-1-1 Showa-cho, Kariya-shi, Aichi F-term in Denso Co., Ltd. 3G066 AA07 AB02 AC09 AD12 BA12 BA33 BA49 BA55 BA67 CC06T CC08T CC14 CC64T CC66 CC67 CC68U CC70 CE22 DC04 DC14 DC18 3H106 DA07 DA13 DA23 DB02 DB12 DB26 DB32 DC06 DD03 EE24 EE30 EE33 GB01 GB06 GC04 GC12 KK18

Claims (4)

[Claims] A valve member accommodating the valve member in a reciprocating manner; a piston member disposed on an inner periphery of the valve member and slidable relative to the valve member. And, the fluid passage is closed by the seating of the valve member,
A valve seat that opens the fluid passage when the valve member separates, a solenoid that generates a magnetic force to attract the valve member when energized, and is disposed on a side of the piston member opposite to the valve seat. A stopper member that locks the piston member and restricts the movement of the piston member in a direction opposite to the valve seat. A gap is formed between an outer peripheral wall of the valve member and an inner peripheral wall of the valve body. The solenoid valve is formed, and the piston member is swingably locked to the stopper member. 2. A cylindrical valve member, a valve body accommodating the valve member in a reciprocating manner, and a piston member disposed on an inner periphery of the valve member and slidable relative to the valve member. And, the fluid passage is closed by the seating of the valve member,
A valve seat that opens the fluid passage when the valve member separates, a solenoid that generates a magnetic force to attract the valve member when energized, and is disposed on a side of the piston member opposite to the valve seat. A stopper member that locks the piston member and restricts the movement of the piston member in a direction opposite to the valve seat. A gap is formed between an outer peripheral wall of the valve member and an inner peripheral wall of the valve body. A solenoid valve formed, wherein the piston member and the stopper member slide on a concave spherical surface and a convex spherical surface. 3. An inner diameter of the valve member is formed to be substantially the same diameter, a contact portion of the valve member seated on the valve seat is formed in a tapered shape, and an inner diameter of the valve member is a seat diameter of the valve member. The solenoid valve according to claim 1, wherein the solenoid valve is substantially equal to: 4. A needle valve for opening and closing an injection hole, a control pressure chamber for introducing high-pressure fuel is provided on a side of the needle valve opposite to the injection hole, and the fuel pressure of the control pressure chamber is controlled by the needle valve. Claims 1 and 2 which act in a direction to close the injection hole.
A fuel injection valve, wherein the fuel pressure in the control pressure chamber is adjusted by intermittently connecting the control pressure chamber and the fuel low pressure side by the solenoid valve according to claim 3.