JPH10121989A - Hydraulic control valve - Google Patents

Abstract

(57) [Problem] To provide a hydraulic control valve with good valve opening response regardless of the pressure on the high pressure side. A high pressure side passage (31) is provided in a valve body (307).
2 is formed so as to open to the inner peripheral surface 310 a of the valve cylinder 310, and the low-pressure side passage 311 is formed so as to face the tip of the valve needle 313. Shaft 313 of valve needle 313
By providing a portion 316 which has the same cross-sectional shape as the inner peripheral surface 310a of the valve cylinder 310 and folds over the portion 316a, the high pressure fuel is prevented from flowing into the spring chamber 306. A through hole 315 is formed in the valve needle 313 so that the low pressure side passage 31 is formed.
By making the spring 1 and the spring chamber 306 always communicate with each other, the pressures of the two are made equal so that the valve needle 313 is operated only by the urging force of the spring 305 and the solenoid coil 319.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic control valve used for controlling an injection timing of a fuel injection pump of a diesel engine.

[0002]

2. Description of the Related Art Among the fuel injection pumps used in diesel engines and the like, those of the distribution type are disclosed in
As described in Japanese Patent No. 10640 or the like, a timer device for controlling the fuel injection timing is provided. The timer device adjusts the fuel injection timing by changing the timing of the cam movement for reciprocating the plunger for pumping the fuel, and has a timer piston interlocked with a face cam or the like for changing the cam movement timing. ,
The position of the timer piston is changed by adjusting the oil pressure that presses the end face with a hydraulic control valve.

As a hydraulic control valve, one that is electromagnetically controlled by a solenoid coil to open and close is described in, for example, Japanese Utility Model Laid-Open No. 56-173736. In order to reduce the cost of such a hydraulic control valve, a fuel injection valve component used for injecting fuel into an intake pipe in a gasoline engine has been used.
FIG. 7 shows an example of the fuel injection valve. A valve needle 603 is inserted into a valve cylinder 602 formed in the valve body 601 and is movable left and right. Drive unit 60
5 includes a spring 606 for applying an urging force in the valve closing direction to the armature 604 integrated with the valve needle 603, and a solenoid coil 607 for applying an urging force in the valve opening direction.
The shim 608 regulates the movement of the valve needle 603 in the valve opening direction and regulates the lift amount of the valve portion 609. The fuel is introduced from the fuel supply port 610 and reaches the fuel storage chamber 613 through a spring chamber 611 in which the spring 606 is accommodated and a flow path 612 on the side surface of the valve needle 603. Driving unit 6 composed of main parts such as solenoid coil 607
05 is used as a component of the hydraulic control valve. JP 60
JP-A-132038 and JP-A-2-21374 disclose a hydraulic control valve using parts of such a fuel injection valve.

FIG. 8 shows a timer device of a distribution type fuel injection pump described in Japanese Patent Application Laid-Open No. Sho 60-132038. The hydraulic control valve 707 used here is of a bottom feed type, and the fuel is a fuel passage 704 that connects a timer high pressure chamber 702 and a timer low pressure chamber 703 provided on both sides of a timer piston 701 that slides the timer cylinder 700. , 70
5 is provided in the middle. In the hydraulic control valve 707, a flow passage 710 communicating with a housing chamber 708 that receives fuel from the timer high-pressure chamber 702 is formed in a valve body 709. The flow path 710 communicates with a flow path 712 on a side surface of the valve needle 711. When the valve is open, the fuel is
From 0,712, the valve section 713 passes through the fuel flow path 705 to the timer low-pressure chamber 703.

[0005]

However, in the timer device described in Japanese Patent Application Laid-Open No. Sho 60-132038, the timer piston 701 receives the reaction force of the face cam during the fuel feeding process, and the timer high pressure chamber 702 sets the injection pressure. The pressure increases in proportion to the pressure and reaches about 100 atm. The flow path 712 on the side surface of the valve needle 711 communicates with the spring chamber 714, and the fuel pressure in the spring chamber 714 causes a considerable force in the valve closing direction to the valve needle 711 (leftward in the figure).
Works. As a result, there is a problem that the valve opening responsiveness changes depending on the pressure of the timer high-pressure chamber 702 if the driving unit of the fuel injection valve is simply used, and the injection timing cannot be controlled with sufficient accuracy.

Accordingly, the present invention has been made in view of the above-mentioned problems of the prior art, and has a stable valve-opening response even if the pressure on the high-pressure side fluctuates. The purpose is to provide a valve.

[0007]

According to the first aspect of the present invention, a valve needle is inserted into a valve cylinder formed in a valve body, and a spring for applying a biasing force to the valve needle is provided in a spring chamber communicating with the valve cylinder. A hydraulic control valve provided with a solenoid coil for applying an electromagnetic force to an armature substantially integral with a valve needle, the valve body includes a valve cylinder and a high-pressure side passage communicating with a high-pressure fluid passage inside the valve cylinder. A low-pressure side passage communicating with the low-pressure fluid passage is formed so as to open at a position facing the distal end surface of the valve needle, and an opening of the low-pressure side passage is provided at the valve at the distal end of the valve needle. A valve seat for receiving the body. The valve needle shaft has at least one portion having the same cross-sectional shape as the valve cylinder and slidably in contact with the inner peripheral surface of the valve cylinder at a position closer to the spring chamber than the opening position of the high-pressure passage. Always shut off the room. In addition, a communication path for communicating the low-pressure side passage with the spring chamber is provided.

The portion of the valve needle that folds over the inner peripheral surface of the valve cylinder prevents the flow of high-pressure fluid from the high-pressure side passage to the spring chamber. Since the communication passage communicates the low-pressure side passage with the spring chamber, the pressure becomes equal between the low-pressure side passage and the spring chamber, and substantially no extra force other than the urging force of the spring and the solenoid coil acts on the valve needle. . Thus, even when the pressure in the high-pressure side passage fluctuates, the valve opening response is stabilized. Moreover, since a complicated member is not required, it can be easily implemented.

In the invention according to claim 2, the communication path is
A through hole is formed in the valve needle so that the distal end surface and the proximal end surface are located at the opening positions.

[0010] Since the communication passage only needs to form a through hole, it can be implemented very easily, and at the same time, the valve needle can be reduced in weight.

According to the third aspect of the present invention, the valve needle formed on the valve cylinder and the substantially annular shim has a shaft portion with a large diameter on the valve cylinder side and is restricted from moving toward the spring chamber. A hydraulic control, comprising a solenoid coil that is disposed in a spring chamber communicating with a valve cylinder via a shim and that applies a biasing force to a valve needle, and that applies an electromagnetic force to an armature substantially integral with the valve needle. In the valve, together with the valve cylinder, a high-pressure side passage communicating with the high-pressure fluid passage is formed in the valve body so as to open to the inner peripheral surface of the valve cylinder, and a low-pressure side passage communicating with the low-pressure fluid passage is formed at the tip of the valve needle. Formed so as to open at a position facing the surface,
The opening of the low-pressure side passage is formed as a valve seat for receiving the valve body at the tip of the valve needle. In the valve needle, at least one portion having the same cross-sectional shape as the valve cylinder and slidably contacting the inner peripheral surface of the valve cylinder is formed on the shaft portion of the valve needle closer to the spring chamber than the opening position of the high-pressure passage. Always shut off the spring chamber. In addition, a through hole is formed in the valve needle such that the distal end surface and the proximal end surface are in the open position, and the low pressure side passage and the spring chamber are communicated. The diameter of the through hole is increased at the large diameter position of the valve needle.

A portion of the valve needle that folds over the inner peripheral surface of the valve cylinder prevents the flow of the high-pressure fluid from the high-pressure side passage to the spring chamber. Since the low-pressure side passage and the spring chamber communicate with each other through the through hole, the pressure is equalized in the low-pressure side passage and the spring chamber, and no extra force other than the urging force of the spring and the solenoid coil acts on the valve needle. Thus, even when the pressure in the high-pressure side passage fluctuates, the valve opening response is stabilized. In addition, since it is only necessary to form a through hole, it can be carried out extremely easily. Since the diameter of the through hole is partially increased, the valve needle can be further reduced in weight.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A hydraulic control valve of the present invention is provided with a face cam type distribution type fuel injection pump (hereinafter, referred to as a diesel engine) for a diesel engine.
An example in which the present invention is applied to a timer device of a fuel injection pump will be described with reference to the drawings. Prior to the description of the hydraulic control valve, the fuel injection pump and its timer device will be described. FIG. 4 is an overall configuration diagram of the fuel injection pump 1, and FIG.
3 is an enlarged sectional view of the timer device 2. FIG. The drive shaft 101 of the fuel injection pump 1 is driven by an engine (not shown) in synchronism with half the rotation of the engine.
Is mounted coaxially with a signal rotor 102. A plurality of convex teeth are formed on the outer periphery of the signal rotor 102, and a rotation angle sensor 103 opposed thereto is formed.
Generates a pulse signal corresponding to the engine speed by electromagnetic induction of the convex teeth of the signal rotor 102, and outputs the pulse signal to the electronic control device 104. The electronic control device 104 has a drive circuit for driving a spill valve 105 and a hydraulic control valve 3 described in detail later.

A face cam 107 for driving a plunger 106 for feeding fuel is connected to the drive shaft 101. The drive shaft 101 and the face cam 107 function to pressurize and feed fuel. The face cam 107 is integrated with the plunger 106 and the roller ring 1
09 is pressed against the roller 110 attached.
The drive shaft 101 is connected to a vane type pump 111 which is a fuel feed pump.

Therefore, when the face cam 107 is rotationally driven by the drive shaft 101, the convex portion of the face cam 107 rides on the roller 110, and the face cam 107 and the plunger 106 integrated with the same are rotated. Reciprocate in the axial direction. Since the plunger 106 is inserted into the cylinder bore 113 of the pump cylinder 112 to form a pressure chamber 113a at its tip, the volume of the pressure chamber 113a expands / contracts due to the reciprocating motion component of the plunger 106, and at the same time, the rotational motion of the plunger 106 increases. A fuel suction port or a discharge port is switched to communicate with the pressure chamber 113a depending on the component.

The discharge port 111 of the feed pump 111
The fuel discharged from a and pressurized to about 10 atm is stored in the fuel chamber 114, and when the suction port communicates with the pressure chamber 113a, the fuel is sucked into the pressure chamber 113a.
The sucked fuel is pressurized to a high pressure as the plunger 106 moves to the right in the figure, and is sent to the fuel injection valve 4 from the discharge port at a predetermined timing, and is injected into the combustion chamber of a diesel engine (not shown). Will be done.

The dismount 115 of the fuel injection pump 1 is provided with a spill valve 105 for releasing the pressure in the pressure chamber 113a. In addition to the output signal from the rotation angle sensor 103 described above, the electronic control device 104 includes a top dead center signal (TDC signal) from the engine and an accelerator opening indicating the magnitude of the engine load, as shown in FIG. Signal, a water temperature signal from a water temperature sensor that detects a cooling water temperature, etc., is input,
Fuel injection control is performed based on these signals.

The cylindrical outer peripheral surface 10 of the roller ring 109
9a can rotate within a predetermined angle range around the axis of the drive shaft 101. Since the position of the roller 110 moves in the rotation direction by the rotation, the timing at which the convex portion of the face cam 107 rides on the roller 110 can be changed, thereby changing the fuel injection timing.

The timer device 2 for moving the position of the roller 110 in the rotation direction based on a control signal from the electronic control device 104 is fixed to the roller ring 109 and has a slide pin 201 for rotating the roller ring 109. The lower end extends into a timer cylinder 202 provided in the pump housing 100 and is engaged with a timer piston 203. The timer piston 203 is held in the timer cylinder 202 so as to be able to reciprocate up and down with respect to the paper surface (FIG. 5).

Although FIG. 4 shows the drive shaft 101 and the timer piston 203 in parallel, the latter intersects the former at a right angle. Similarly, the axis of the feed pump 111 is an extension of the drive shaft 101 on the same axis, but is drawn by rotating the drive shaft 101 by 90 degrees.

In FIG. 5, a timer high-pressure chamber 204 above a timer piston 203 is connected to a fuel chamber 1 via a throttle 203 a and a check valve 205 provided in the timer piston 203.
14 (FIG. 4) and feed pump 111
It receives fuel pressurized by (FIG. 4). The hydraulic pressure pushes the timer piston 203 downward in the figure, and a timer spring 207 is mounted in the timer low-pressure chamber 206 below the timer piston 203 in opposition thereto. The timer low pressure chamber 206 includes the feed pump 11
The first suction port 116 (FIG. 4) communicates with the first suction port 116, and the pressure is always low during operation. The oil pressure of the fuel acting on the timer high-pressure chamber 204, that is, the supply pressure, changes in relation to the engine speed, and thus the speed of the drive shaft 101 (FIG. 4). When the timer piston 203 moves to a position where the biasing force is balanced, and the roller ring 109 (FIG. 4) is rotated and adjusted via the slide pin 201, the fuel injection timing changes according to the engine speed. become. Also, during the pressure feeding process of the plunger 106 (FIG. 4), the timer piston 203 receives the pressure feeding reaction force upward in the drawing via the slide pin 201 by the pressure feeding reaction force received by the face cam 107 (FIG. 4). Chamber 204 temporarily reaches about 100 atmospheres.

In the pump housing 100, a fuel passage 208 as a high pressure fluid passage communicating with the timer high pressure chamber 204 and a fuel passage 209 as a low pressure fluid passage communicating with the timer low pressure chamber 207 are formed. Channels 208, 20
9 is connected via the hydraulic control valve 3. The hydraulic control valve 3 is fixed to the pump housing 100 by a flange 210 and a bolt 211, and outputs an open / close signal, which is a control signal of an injection timing, to the hydraulic control valve 3 by an electronic control device 104.
It is electrically connected to Thus, the hydraulic control valve 3 is controlled to be opened and closed by the electronic control device 104 and the timer high-pressure chamber 20 is controlled.
4 is partially released to the timer low-pressure chamber 206 to adjust the position of the timer piston 203 and the roller ring 10.
9 in the rotation direction. Thereby, the fuel injection timing is controlled.

FIG. 1 is an enlarged sectional view of the hydraulic control valve 3, and FIG.
The main components such as the solenoid coil of the fuel injection valve shown in FIG. A tubular stator 302 having a smaller diameter than that of the tubular casing 301 is coaxially disposed in the tubular casing 301 serving as a housing, and reaches the middle of the casing 301. The stator 302 has a flange portion 303 formed in the middle of the stator 302 and a right edge 301 of the casing 301.
a and caulked. The inner space 306 of the stator 302 is a spring chamber 306 described later, and the right side in the figure is closed by a spring guide 304.

A casing 301 is provided with a valve body 307 having a circular cross section and a substantially annular shim 308 in this order coaxially from the left side in the figure. The valve body 307 and the shim 308 are positioned by a step portion 301 c formed on the inner peripheral surface of the casing 301 by the shim 308, and are caulked and fixed at the left end 301 b of the casing 301 by the valve body 307.

The valve body 307 is formed with a through hole 309 which is sufficiently larger than the inner diameter of the shim 308 along the axial direction. The through hole 309 is formed as the valve cylinder 310 except for the short end portion 311, and the end portion 311 is formed as the low-pressure side passage 311. The low-pressure side passage 311 communicates with a fuel flow passage 209 communicating with the timer low-pressure chamber 206 through a lateral hole 3111 formed in a side wall of the valve body 307. The timer high-pressure chamber 204 is provided on a side wall of the valve body 307.
High-pressure side passage 31 communicating with fuel passage 208 communicating with
2 is formed, and the inner peripheral surface 31 of the valve cylinder 310 is formed.
0a. Inner peripheral surface 3 of valve cylinder 310
10a is an annular recess 3 at the opening position of the high pressure side passage 312.
10b is formed.

The valve cylinder 310 has a valve needle 31
3 is inserted. The valve needle 313 is a substantially rod-shaped member,
The part 313b that is the position of the shim 308 is constricted.

FIG. 2 is an enlarged cross-sectional view of the vicinity of the distal end portion 314 of the valve needle 313 as a valve body. The distal end 314 of the valve needle 313 has an end edge 314a formed into a conical surface and serves as a seal portion 314a. Since the concave portion 310b is formed in the inner peripheral surface 310a of the valve cylinder 310, the timer high-pressure chamber 204 (FIG. 4) is provided in a space surrounding the valve needle 313.
Higher pressure fuel is provided. The low-pressure side passage 311 is formed in the recess 310 on the inner peripheral surface 310 a of the valve cylinder 310.
The position of the stepped portion b is the open end, and the open end edge 311a is machined into a conical surface with a reduced diameter on the left side in the figure and serves as a valve seat 311a for receiving the seal portion 314a of the valve needle 313.

In the hydraulic control valve 3 of the present embodiment, the valve needle 313 has a valve diameter d ₁ of 5.0 mm, an inclination angle θ ₁ of the conical surface of the seal portion 314a of 93 degrees, and the valve body 3
07 of the valve seat 311a has a conical surface the maximum diameter d ₂ 5.1 mm (>
d ₁ ), the inclination angle θ ₂ is 90 degrees (<θ ₁ ), and when the valve is closed, the seal edge 314b, which is the largest diameter portion of the conical surface of the seal portion 314a, comes into close contact with the conical surface of the valve seat 311a and the high pressure side. The passage 312 and the low-pressure side passage 311 are shut off.

The valve needle 313 is connected to the valve cylinder 31
The shaft portion 313a at the zero position has the same cross-sectional shape as the valve cylinder 310 except for the middle of a slightly smaller diameter, and folds on the inner peripheral surface 310a of the valve cylinder 310. The side passage 312 and the spring chamber 306 are shut off.

The valve needle 313 has a through hole 315 which is a communication passage along the axis.
3 are open to the distal end surface 313d and the proximal end surface 313e.
The through hole 315 has a large diameter at the position of the valve cylinder 310. Here, the diameter of the through hole 315 was set as follows. In the hydraulic control valve 3 of the present embodiment, the shim 308 is also the same as that of the fuel injection valve. FIG. 3 shows a shim 30
8 (A) is a plan view and FIG. 8 (B) is a sectional view. The shim 308 is opened by cutting out a part of the ring for assembling the valve needle 313. The diameter d ₃ of the constriction 313 b of the valve needle 313 is equal to the diameter of the opening 30 of the shim 308.
Since 8a is set to 2.7 (upper / lower dimensional tolerance: 0, 0.15) mm, it must be smaller than 2.7 mm. Therefore, φd ₃ = 2.45 (upper and lower dimensional tolerance 0,0.15)
And

On the other hand, the diameter of the through hole 315 needs to be 1.1 mm or more in view of the required flow rate and the like. Also, the valve needle 313
The constriction 313b has a sectional area of 3.3 in consideration of strength.
mm ² or more is desirable. Then, in order to make the cross-sectional area of the constricted portion 313b not less than 3.3 mm ^{2 when} φd ₃ = 2.45, the diameter φd ₄ of the through hole 315 in the constricted portion 313b of the valve needle 313 is not more than 1.3. . Then φd
₄ is 1.2 (upper and lower dimensional tolerance 0, 0.1) mm.

The diameter d ₅ of the through hole 315 at the position of the valve cylinder 310 is made larger than the diameter d ₄ of the through hole 315 in the constricted portion 313 b of the valve needle 313 so that the strength of the valve needle 313 does not decrease. The weight of the valve needle 313 is reduced. Therefore, the through-hole 315 not only allows the low-pressure side passage 311 to communicate with the spring chamber 306 but also contributes to reducing the weight of the valve needle 313.

A portion 313c of the valve needle 313 projecting from the shim 308 toward the spring chamber 306 is press-fitted into a short, bottomed cylindrical armature 317. Armature 31
7 is open at the bottom, and communicates with the through hole 315 of the valve needle 313 through the inside of the armature 317.

The armature 317 faces the stator 302 with an interval (air gap) l. Stator 3
A spring 305 is provided in the spring chamber 306 of 02, and applies a biasing force to the armature 317 in the left direction in the figure.

A coil bobbin 318 is coaxially arranged between the casing 301 and the stator 302, and a solenoid coil 319 is wound therearound. When the solenoid coil 319 is energized from the electronic control unit 104 (FIG. 4) via the terminal 320, the stator 302 applies an attractive force to the armature 317 to the right in the figure by electromagnetic force.

The operation of the hydraulic control valve 3 will be described together with the operation of the fuel injection pump 1. A pulse-like opening / closing control signal is input to the solenoid coil 319 of the hydraulic control valve 3.
That is, when the solenoid coil 319 is not energized, the distal end 314 of the valve needle 313 is
a, the hydraulic control valve 3 is closed as shown in FIG. 1 to cut off the communication between the timer high-pressure chamber 204 and the timer low-pressure chamber 206. When the solenoid coil 319 is energized, the armature 317 is attracted by the stator 302 and moves rightward in the figure against the spring force of the spring 305, and the seal edge 314b of the valve needle 313 integrated with the armature 317 and the valve body. 307 valve seat 31
1a, the hydraulic control valve 3 is opened, and the timer high-pressure chamber 204 and the timer low-pressure chamber 206 communicate with each other.

The electronic control unit 104 sets the open duty ratio of the hydraulic control valve 3 according to the command value of the fuel injection timing, and stops at the position where the pressures applied to the upper and lower end surfaces of the timer piston 203 are balanced. The angle is retarded as the open duty ratio increases. In consideration of the case where the solenoid coil 319 is broken, the hydraulic control valve 3 is normally closed as described above so that the fuel injection timing is advanced most in this case.

In the hydraulic control valve 3 of the present invention, the high pressure side passage 31
2 is cut off from the spring chamber 306 by the fold portion 316 of the valve needle 313, so that the high-pressure fuel from the timer high-pressure chamber 204 does not flow into the spring chamber 306 even during the fuel pumping step. The low pressure side passage 311 communicates with the spring chamber 306 by a through hole 315 of the valve needle 313. Therefore, the pressure at which the fuel in the low-pressure side passage 311 presses rightward in the figure and the pressure at which the fuel in the spring chamber 306 presses leftward in the figure balance, so that the valve needle 313 does not depend on the pressure fluctuation of the timer high-pressure chamber 204. The responsive operation is performed by the spring force of the spring 305 and the electromagnetic force of the solenoid coil 319. Therefore, the hydraulic control valve 3 can exhibit sufficient performance by using the drive unit of the fuel injection valve of the gasoline engine with a large production volume, and the cost can be reduced.

Moreover, the valve needle 313 only needs to drill a through hole 315 in the rod-shaped member. Therefore, according to the present invention, not only can the response be improved very easily, but also the valve needle does not need to be processed into a shape having complicated irregularities as in the fuel injection valve of FIG. 7 and the hydraulic control valve of FIG. In both cases, there is an extremely excellent effect that the weight can be reduced.

(Second Embodiment) FIG. 6 shows a second hydraulic control valve of the present invention. In this embodiment, another valve needle 313A is used in place of the valve needle of the hydraulic control valve of the first embodiment. In the drawing, the same elements as those in FIG. The explanation will focus on the points.

The valve cylinder 3 of the valve needle 313A
Folding portions 316a, 316b of inner surface 10a with inner peripheral surface 310a
The sectional shape of the fold 316b on the shim 308 side is not the same as the inner peripheral surface 310a of the valve cylinder 310, but four cut surfaces 321 are formed at symmetrical positions.
There is a gap between 6b and the inner peripheral surface 310a of the valve cylinder 310. The valve needle 313A is provided with an armature 317.
The cross-sectional shape of the portion 313c to be pressed into the armature 31 is
7 is not the same as the inner peripheral surface 317a but has four cutting surfaces 322 at symmetrical positions, and there is a gap between the portion 313c of the valve needle 313A and the inner peripheral surface 317a of the armature 317.

The valve needle 313A has a T-shaped hole 315.
A is formed, one end of which is open to the distal end surface 313d of the valve needle 313A, and the other end is open to the outer peripheral surface 313f at a position sandwiched between the fold 316a and the fold 316b.

Thus, the low pressure side passage 311 is
5A, through the gap between the valve cylinder 310 and the valve needle 313A, and through the gap between the shim 308 and the valve needle 313A, and communicates with the spring chamber 306 through the communication path P formed by the gap between the inner peripheral surface 317a of the armature 317 and the valve needle 313A.

Also in the present embodiment, good responsiveness can be obtained.

The present invention is not a timer type high pressure chamber control type distributed fuel injection pump which controls the timer high pressure chamber pressure by a hydraulic control valve, but a timer low pressure chamber control which controls the timer low pressure chamber pressure by a hydraulic control valve. It can also be applied to a distributed fuel injection pump of the type.

In each of the above embodiments, the hydraulic control valve of the present invention is applied to a face-cam pressure-feed type distributed fuel injection pump. However, the present invention is not limited to this. Of course, it may be provided between a high-pressure fluid flow path and a low-pressure fluid flow path, such as a pump or a row-type fuel injection pump, and may be applied to pressure control on the high pressure side or the low pressure side.

[Brief description of the drawings]

FIG. 1 is an overall sectional view of a first hydraulic control valve of the present invention.

FIG. 2 is a partial sectional view of a first hydraulic control valve of the present invention.

3A is a plan view of one part of the first hydraulic control valve of the present invention, and FIG. 3B is a plan view of IIIB-II in FIG.
It is sectional drawing which follows the IB line.

FIG. 4 is an overall configuration diagram of a face cam type fuel injection pump to which the first hydraulic control valve of the present invention is assembled.

FIG. 5 is a sectional view of a main part of a face cam type fuel injection pump to which the first hydraulic control valve of the present invention is assembled.

FIG. 6 is an overall sectional view of a second hydraulic control valve of the present invention.

FIG. 7 is an overall sectional view of a fuel injection valve of a gasoline engine.

FIG. 8 is a sectional view of a main part of a face cam type fuel injection pump to which one conventional hydraulic control valve is assembled.

[Explanation of symbols]

 Reference Signs List 1 fuel injection pump 2 timer device 208 fuel passage (high-pressure fluid passage) 209 fuel passage (low-pressure fluid passage) 3 hydraulic control valve 301 casing (housing) 302 stator (housing) 305 spring 306 spring chamber 307 valve body 308 shim 310 Valve cylinder 311 Low pressure side passage 312 High pressure side passage 311a Valve seat 313, 313A Valve needle 313a Shaft portion 313d Tip surface 313e Base end surface 314 Tip portion (valve body portion) 315 Through hole (communication passage) 316, 316a Folding portion 317 Armature 319 Solenoid coil P communication passage

Claims (3)

[Claims] A valve formed in a valve body by integrally connecting a valve body having a high-pressure side passage communicating with a high-pressure fluid passage and a low-pressure side passage communicating with a low-pressure fluid passage, and a cylindrical housing. The cylinder and the inner space of the housing are communicated with each other, and a valve needle for switching the communication between the high-pressure side passage and the low-pressure side passage and shutoff is inserted in the valve cylinder, and an armature substantially integrated with the valve needle is provided in the housing. In a hydraulic control valve including a solenoid coil that constantly arranges a spring for applying an urging force to form a spring chamber and applies an electromagnetic force to the armature in a direction opposite to the urging force of the spring, the valve body includes a high-pressure side passage. Is formed so as to open on the inner peripheral surface of the valve cylinder, and the low-pressure side passage is opened at a position facing the distal end surface of the valve needle. The opening of the low pressure side passage is formed as a valve seat that receives the valve body at the tip of the valve needle.The shaft of the valve needle has the same cross-sectional shape as the valve cylinder and the inner peripheral surface of the valve cylinder. At least one foldable portion is formed closer to the spring chamber than the opening position of the high-pressure side passage, so that the high-pressure side passage and the spring chamber are always shut off, and the low-pressure side passage communicates with the spring chamber. A hydraulic control valve having a passage. 2. The hydraulic control valve according to claim 1, wherein the communication passage is a through hole formed in the valve needle such that a distal end surface and a proximal end surface of the valve needle are open. 3. A valve body in which a high-pressure side passage communicating with a high-pressure fluid passage and a low-pressure side passage communicating with a low-pressure fluid passage are formed integrally with a cylindrical housing via a substantially annular shim. A valve cylinder formed in the valve body and the housing are communicated via a shim. The valve cylinder and the shim are valve needles for switching between communication and disconnection between a high-pressure side passage and a low-pressure side passage. A large-diameter valve needle that restricts movement in the direction of the spring chamber is inserted on the cylinder side, and a spring that constantly applies a biasing force to an armature substantially integral with the valve needle is arranged in the housing. A hydraulic control valve equipped with a solenoid coil that applies an electromagnetic force to the armature in the opposite direction to the biasing force of the spring. The high pressure side passage is formed so as to open to the inner peripheral surface of the valve cylinder, and the low pressure side passage is formed so as to open at a position facing the valve needle on the distal end side from the opening position of the high pressure side passage, The opening of the low-pressure side passage is a valve seat that receives the valve body at the tip of the valve needle, and the shaft of the valve needle has a section that is the same in cross-section as the valve cylinder and folds into the inner peripheral surface of the valve cylinder. At least one on the spring chamber side of the opening position of the side passage
The high pressure side passage and the spring chamber are always shut off by forming a portion, and a through hole is formed in the valve needle so that the distal end surface and the base end surface thereof are in the open position, and the low pressure side passage and the spring chamber are formed. A hydraulic control valve characterized in that the communication is established and the diameter of the through hole is increased at the large diameter position of the valve needle.