JP3355848B2 - Solenoid driven hydraulic control valve - Google Patents

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, and more particularly to a solenoid-operated hydraulic control valve applied to a fuel injection device of an internal combustion engine.

[0002]

2. Description of the Related Art As a conventional solenoid-driven hydraulic control valve, there is a hydraulic control valve using a balance rod as disclosed in Japanese Patent Application Laid-Open No. Hei 5-332220, for example. The configuration and operation of the hydraulic control valve will be described with reference to FIG.

A known nozzle 102 is screwed below a holder 101 of the hydraulic control valve 100 by a retainer 103, and a needle 105 is slidable by a pressure of a pressure spring 107 through a spring holder 106. Clearance larger than 105 diameter is 2-3
It is urged in the seating direction by the fuel pressure acting on the upper end of the μm command piston 108. An outer valve 111 is inserted with a clearance of 2 to 3 μm so as to slide in a guide hole 110 formed in the left and right direction inside the holder 101, and is pushed rightward by a spring 112. Outer valve seat 11
3 seated. An inner valve 117 having an inner valve seat 116 and having a clearance of 2 to 3 μm is inserted into a left center hole 115 in the outer valve 111 and is pushed to the left by fuel pressure. A balance rod 11 having the same diameter as the inner valve seat 116 and having a clearance of 2 to 3 μm is slidably provided in the center hole on the right side.
8 are accommodated and pushed to the right by fuel pressure.

The high-pressure port 120 is provided in the annular high-pressure groove 12.
1. The fuel port 122 in the holder 101, the fuel port 123 in the nozzle 102, and the oil reservoir 125 are communicated in this order to the vicinity of the injection hole 126. Also, the high pressure groove 121
Is the radial fuel port 1 in the outer valve 111
27, since it also communicates with the fuel port 128 in the axial direction, when the outer valve 111 moves to the right as shown in FIG.
The upper end of the command piston 108 also communicates with the back pressure chamber 130.

A spring chamber 131 in which the pressure spring 107 is accommodated communicates with a spring chamber 133 in which the spring 112 is accommodated by a port 132, and the spring chamber 133 communicates with a drain port 136 by a port 135. I have. The annular low-pressure groove 137 in the outer valve 111 also communicates with the drain port 136 in the order of the radial port 138 and the annular low-pressure groove 140 in the holder 101.

Next, the operation of the conventional hydraulic control valve 100 will be briefly described. FIG. 4 shows a state in which fuel injection is stopped.
When power is supplied to the outer valve 111, the outer valve 111 is sucked leftward and separates from the outer valve seat 113, and sits on the inner valve seat 116. Thereby, the back pressure chamber 1
30 is communicated with the drain port 136 and the oil pressure is reduced, so that the needle 105 is pushed upward by the pressure of the oil reservoir 125 communicating with the high pressure port 120 to open the injection hole 126 and the fuel injection is started. Be started.

[0007]

In a hydraulic control valve using a balance rod 118 as disclosed in Japanese Patent Application Laid-Open No. Hei 5-332220, there is no problem when the actuator is an electrostrictive actuator. But,
If the actuator is a solenoid type, the needle 105
When the power supply to the solenoid 141 is cut off to close the valve, the hydraulic force applied to the outer valve 111 is completely canceled by the balance rod 118 because the diameter of the inner valve seat 116 and the diameter of the balance rod 118 are the same. Therefore, the force for closing the outer valve 111 is only the spring force of the spring. However, the solenoid 14
Since the residual magnetism still remains even when the power supply to the solenoid 1 is stopped, the time required for the residual magnetism to disappear disappears.
Since the magnetic force of the valve 41 acts in the valve opening direction of the valve 111, a large response delay occurs when the valve 111 is closed, and there is a problem that a minute injection amount cannot be adjusted. This problem is not limited to the illustrated three-way valve type hydraulic control valve, but can also occur with a two-way valve type hydraulic control valve using a similar balance rod.

The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to eliminate a valve response delay caused by residual magnetism of a solenoid, and to achieve a small injection. An object of the present invention is to provide a solenoid-operated hydraulic control valve capable of adjusting a quantity.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a first valve, which is driven by a solenoid to suction and communicate hydraulic pressure, and that the first valve is connected to the solenoid by a suction force of the solenoid. In the solenoid-operated hydraulic control valve having a spring that biases in the opposite direction,
A second valve having a valve seat at a lower portion is slidably fitted into a hole provided in the valve, and a space is provided with the second valve below the hole to achieve balance. The rod is slidably inserted and provided, and the diameter of the valve seat is made larger than the diameter of the balance rod, so that the hydraulic acting force on the first valve is in the opposite direction to the suction force of the solenoid. It is characterized by acting.

Preferably, the solenoid-operated hydraulic control valve is a three-way valve.

According to another aspect of the present invention, there is provided a spring for a valve which is driven by a solenoid to communicate and shut off hydraulic pressure, and for urging the valve in a direction opposite to a suction force of the solenoid. In a solenoid-operated hydraulic control valve having a valve, a balance rod is slidably fitted in a hole provided in a valve having a valve seat portion at a lower portion, and the lower surface of the balance rod and the hole are The lower chamber formed is communicated with the vicinity of the seat portion through a communication passage, and the diameter of the balance rod is made larger than the diameter of the seat portion. It is characterized in that it acts in the opposite direction to the force.

Preferably, the solenoid-driven hydraulic control valve is a two-way valve.

[0013] Further, the solenoid-operated hydraulic control valve includes:
The spring may be omitted.

[0014]

According to the first aspect of the present invention, in the solenoid-operated hydraulic control valve of the present invention, a second valve having a valve seat at a lower portion is slidably inserted into a hole provided in the first valve. And the second hole is inserted below the hole.
The balance rod is slidably fitted and opposed to each other by disposing the valve and the space. When the solenoid is energized, the first valve is attracted by the solenoid and rises, and the valve seat of the second valve is seated on the first valve, so that the space is closed at the top. Then, the space is transformed into a working chamber in which the hydraulic working force works.
That is, the diameter of the valve seat that closes the upper part of the working chamber is made larger than the diameter of the balance rod. A hydraulic force is generated to push down.

Therefore, when the energization of the solenoid is stopped, the suction force to the first valve remains for a short time due to the influence of residual magnetism. However, the first valve is urged in the direction opposite to the suction force of the solenoid, that is, the hydraulic force is superimposed on the spring force of the spring that pushes the first valve downward. , The first valve moves quickly downward, and the response delay due to the residual magnetism of the solenoid can be greatly reduced. And the first
When the valve moves away from the valve seat, the downward hydraulic force generated in the working chamber disappears,
At this time, the force of the residual magnetism of the solenoid is hardly affected, so that the first valve smoothly moves downward only by the spring force of the spring. Therefore, the response delay of the first valve due to the influence of the residual magnetism of the solenoid can be greatly reduced, and highly accurate metering can be performed even for a minute injection amount.

Next, in the solenoid-operated hydraulic control valve according to the third aspect of the present invention, a balance rod is slidably fitted into a hole provided in a valve having a seat portion at a lower portion. The lower chamber formed by the lower surface of the balance rod and the hole communicates with the vicinity of the seat portion through a communication passage. Since the diameter of the balance rod is larger than the diameter of the seat portion, the valve is always pushed down and closed by the pressure receiving area difference of the hydraulic pressure acting on the lower chamber and the seat portion. Hydraulic force to valve is working. Now, when the solenoid is energized, the valve is sucked and moves upward, so that the seat portion is unseated, the high pressure port and the drain port communicate, and the pressure in the back pressure chamber drops. Therefore, the accumulated fuel in the oil sump is injected to the outside. Next, when the energization of the solenoid is stopped, the suction force to the valve remains for a short time due to the influence of residual magnetism. However, the valve is urged in the direction opposite to the suction force, that is, the hydraulic action force is superimposed on the spring force of a spring that pushes the valve downward, so that the valve overcomes the suction force and It can quickly move downward, greatly reduce the response delay due to the residual magnetism of the solenoid, and enable high-precision metering up to a very small injection amount.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing a configuration in which a three-way valve type hydraulic control valve according to a first embodiment of the present invention is applied to a pressure accumulating fuel injection device for an internal combustion engine. The accumulator type fuel injection device comprises a three-way valve type hydraulic control valve 1 and a fuel injection unit 2
Consists of The fuel pumped by the fuel pump 3 is stored in the reservoir 5 at a pressure of 2000 kgf / cm ² , and further supplied to a fuel injection device mounted on the engine. The holder (housing) 6 of the hydraulic control valve 1 has a high pressure port 7 communicating with the reservoir 5, a drain port 10 communicating with the fuel tank 8, and a control port 12 communicating with the back pressure chamber 11 of the fuel injection unit 2. Is provided. A solenoid 13 is installed above the holder 6, and the solenoid 13 is connected to a drive circuit 16 via a lead 15.

In the holder 6, communication ports 17a,
17b (hereinafter, “outer valve”)
Called. ) 17 is inserted so as to be slidable up and down in the holder 6 and is urged downward by a spring 18. Normally (when the solenoid is not energized) The outer valve seat 20 of the outer valve 17 is seated on the holder 6. A second valve (hereinafter, referred to as an “inner valve”) having an inner valve seat 21 at a lower portion in the outer valve 17.
22 is fitted so as to be able to slide up and down inside the outer valve 17. Below the inner valve 22, high-pressure fuel is introduced from the reservoir 5 through the high-pressure port 7 and the communication port 17a, and the inner valve 22 is normally pushed upward by this fuel pressure. Further, a balance rod 19 slidably fitted in a space with the inner valve 22 is arranged below the inner part of the outer valve 17, and is also slidably movable in the outer valve 17. I can do it. The balance rod 19 is connected to the reservoir 5
, Is normally pushed downward by the fuel pressure of the high-pressure fuel introduced through the high-pressure port 7 and the communication port 17a. When the solenoid 13 is energized and the outer valve 17 is sucked by the solenoid 13 and rises, when the inner valve seat 21 of the inner valve 22 is closed by seating on the outer valve 17, the hydraulic action force is applied. The function as the action chamber 22a in which the works. That is, in this embodiment, the diameter ds of the inner valve seat 21 that closes the upper part of the working chamber 22a is made larger than the diameter dr of the balance rod 19, so that the difference in the pressure receiving area of the hydraulic pressure acting on the upper and lower surfaces of the working chamber is obtained. As a result, a force is generated in the action chamber to push the outer valve 17 downward,
The force is exerted by releasing the power supply to the solenoid 13. Details will be described later.

The fuel injection section 2 includes a nozzle 25 having a fuel port 23 and an injection hole 24,
The needle 26 is slidably inserted into the nozzle 5 and is movable up and down. An oil reservoir 27 is formed between the needle 26 and the nozzle 25. And the oil sump 27
, High-pressure fuel is introduced from the reservoir 5 through the fuel port 23, and the high-pressure fuel is also supplied to the vicinity of the injection hole 24. On the other hand, the high-pressure fuel stored in the reservoir 5 is supplied to the high-pressure port 7, the communication ports 17a and 17b,
The needle 26 is also pushed down by the fuel pressure supplied to the back pressure chamber 11 through the control port 12 so that the needle 26 is normally pushed down (when the solenoid is not energized). And the injection hole 24 is closed.

Next, the operation of the first embodiment shown in FIG. 1 will be described. State shown in FIG. 1 corresponds to T ₁ in the time chart shown in FIG. 2, the solenoid 13 is not yet energized, corresponding to the state of stopping the injection. 2000 kgf / cm ² of fuel stored in the reservoir 5 is supplied to the high pressure port 7,
The air is supplied to the back pressure chamber 11 of the nozzle 25 via the communication ports 17a and 17b and the control port 12, and is also supplied to the vicinity of the injection hole 24 via the fuel port 23 and the oil reservoir 27. At this time, the needle 26 is in the back pressure chamber 1
The nozzle hole 24 is closed by being pressed downward by the fuel pressure supplied to the needle seat 1 and seated by the needle seat 28.

At this time, the downward force F ₀ applied to the outer valve 17 is given by the following equation. That is, F ₀ = (force of spring 18) + (high pressure fuel pressure) × ｛(guide diameter of inner valve 22) ² − (diameter of balance rod 19) ² − (diameter of outer valve seat 20) ² + (outer valve 17 guide diameter) ² ｝ × π / 4 For example, F ₀ = 5 + 2000 × ｛(0.4) ^2- (0.295) ^2- (0.843) ² + (0.8) ² ｝ × π / 4 ≒ 8.65 kgf.

At the time of starting the injection (T _{2 in} FIG. 2), when a current (for example, 3 A) is supplied from the drive circuit 16 to the solenoid 13 via the lead wire 15, the outer valve 17 strikes the spring force of the spring 18. As a result, it is lifted by 50 μm upward, separated from the outer valve seat 20 and seated on the inner valve seat 21. As a result, the control port 12 is cut off from the high pressure port 7 and communicates with the drain port 10. Therefore, the back pressure chamber 1
Since the pressure of 1 decreases, the needle 26 is pushed up by 0.35 mm by the accumulated fuel pressure of the oil sump 27 and is separated from the needle seat 28. Then, since the injection hole 24 which has been closed is opened, the oil sump 27 and the injection hole 2 are opened.
The high-pressure fuel in the vicinity of 4 blows out from the injection hole 24 at a stretch and starts injection. At this time, as described above, the space is
The upper part is closed by the seating of the inner valve seat 21 to serve as a working chamber 22a in which a hydraulic working force acts, and the working chamber 22a
Due to the difference in the pressure receiving area of the hydraulic pressure acting on the upper and lower surfaces of the a, a force for pushing the outer valve 17 downward is generated. However, since the solenoid 13 is still energized, the suction force of the solenoid 13 is larger, and the outer valve 17 Holds position.

When the injection of the solenoid 13 is stopped when the injection is to be stopped (T _{3 in} FIG. 2), the residual magnetism remains for a short while, but the outer valve 17
, An attractive force (Fr) due to some residual magnetism acts. Force F ₁ downward acting on the outer valve 17 at this stage is shown in the following equation. F ₁ = (force of spring 18) + (high pressure fuel pressure) × {(diameter ds of inner valve seat 21) ² − (diameter dr of balance rod 19) ² } × π / 4− (due to residual magnetism suction force Fr) For _{example, F 1 = 5 × 2000 ×} {(0.3) 2 - (0.295) 2} × π / 4-Fr ≒ (5 + 4.6) becomes kgf -Fr.

The present invention is different from the prior art as shown in FIG. 4 in that the diameter dr of the balance rod 19 below the working chamber 22a which defines the space is changed to the working chamber 22.
The diameter dr of the balance rod 19 is selected so that the hydraulic force acts in the direction opposite to the suction force of the solenoid 13 without having the same diameter as the diameter ds of the inner valve seat 21 whose upper part is closed. Things. In the prior art as shown in FIG. 4, when the needle 105 is closed, the rightward force applied to the outer valve 111 is only the spring force of the spring 112, and the attraction force to the outer valve 111 due to residual magnetism of the solenoid 141 is reduced. If the spring force is greater than the spring force of the spring 112, the outer valve 111 does not start moving until the residual magnetism disappears with the passage of time, so that a large response delay occurs.

However, in this embodiment, the working chamber 22
The diameter ds of the inner valve seat 21 that closes the upper part of a
Is set to, for example, 3 mm, and the diameter dr of the balance rod 19 below the action chamber 22a is set to, for example, 2.95 mm.
> Dr, a force for pushing down the outer valve 17 is generated, for example, 4.6 kgf due to a difference in the pressure receiving area of the hydraulic pressure acting on the upper and lower surfaces of the working chamber 22a, and is exerted together with the release of the power supply to the solenoid 13. . This force causes the outer valve 17 to move downward and the inner valve seat 2
It occurs until 1 leaves. Therefore, the needle 26
When There is closed, the outer valve 17 to the spring force 5kgf pressing downward gel force F ₁ is the spring 18, the force of 4.6kgf is superimposed becomes large as 9.6 kgf, even if the force by the residual magnetism of the solenoid 13 Fr , The force that overcomes the force Fr acts downward, so that the outer valve quickly moves downward, thereby greatly reducing the response delay due to the residual magnetism of the solenoid 13 compared to the prior art. Can be reduced. Therefore, the outer valve 17 is separated from the inner valve seat 21 and the outer valve seat 20 is seated. When the outer valve 17 is separated from the inner valve seat 21, the action chamber 22a
The downward force that has been generated at the point of time disappears, and the downward force is only the spring force of the spring 18. At this time, since the force Fr due to the residual magnetism of the solenoid 13 has hardly been affected, The outer valve 17 moves smoothly downward only by the spring force. Thereby, the high-pressure fuel from the reservoir 5 flows through the high-pressure port 7, the communication ports 17a and 17b, and the control port 12 to the back-pressure chamber 11, so that the pressure in the back-pressure chamber 11 lowers the needle 26, and thus , Orifice 2
4 closes and terminates the injection.

In the prior art as shown in FIG. 4, since the diameter of the inner valve seat 116 and the diameter of the balance rod 118 are the same, the hydraulic force applied to the outer valve 111 is canceled out. Used the spring 112 as an essential component. However, in this embodiment, by a proper force of F ₁ by selecting the diameter dr of the balance rod 19 appropriately, it is possible to bias the constantly outer valve 17 downward, in terms of fail-sale outer valve 17 It is also advantageous in view of the above. Further, by making the diameter dr smaller, the spring 18 can be omitted, and the cost can be reduced by reducing the number of components.

FIG. 3 is a sectional view showing a configuration in which a two-way valve type hydraulic control valve according to a second embodiment of the present invention is applied to a pressure accumulating fuel injection device for an internal combustion engine. The accumulator type fuel injection device includes a two-way valve type hydraulic control valve 50 and a fuel injection unit 51. The high-pressure fuel pumped by the fuel pump 52 is
The pressure is accumulated in the reservoir 54 and further supplied to a fuel injection device mounted on the engine. The housing 53 of the hydraulic control valve 50 is provided with a drain port 56 communicating with a fuel tank 55 and a high-pressure port 58 communicating with a back pressure chamber 57 of the fuel injection unit 51. The high-pressure fuel stored in the reservoir 54 from the fuel pump 52 is introduced and stored in the oil sump 61 around the needle 60 of the fuel injection device 51, and is simultaneously stored in the back pressure chamber 57 and the high-pressure port 58 through the throttle 62. Has been introduced. Since high pressure acts on the back pressure chamber 57, the needle 60 descends and normally closes the injection hole (not shown). The valve 63 is inserted into the housing 53 of the hydraulic control valve 50 so as to be slidable in a vertical direction, and is pressed downward by a spring 65 provided at an upper portion to be pressed downward. Sitting. Further, a solenoid 67 is provided above the housing 53.
A balance rod 68 is fitted into the valve 63 so as to be slidable in the vertical direction. Then, the high-pressure fuel introduced into the high-pressure port 58
It is introduced to the lower chamber 71 of the balance rod 68 via a communication passage 70 formed in the valve 63. Therefore, the balance rod 68 is normally pushed upward by a high fuel pressure.

Here, the diameter of the balance rod 68 is dr,
The diameter of the seat portion 66 is ds, and the diameter dr of the balance rod 68 is selected to be larger than the diameter ds of the seat portion 66. That is, assuming that dr> ds and the pressure of the high-pressure fuel sent to the high-pressure port 58 is Pf, due to the difference in the pressure receiving area of the hydraulic pressure acting on the lower chamber 71 and the seat portion 66, the valve 63 is always lowered. Hydraulic force to push down
That is, a force of Pf × (dr ² −ds ² ) × π / 4 always acts in the valve closing direction.

In the above configuration, the solenoid 6
When power is supplied to the valve 7, the valve 63 is sucked and moves upward, so that the seat portion 66 of the valve 63 is unseated, the high-pressure port 58 and the drain port 56 communicate, and the pressure in the back pressure chamber 57 decreases. For this reason, the needle 60 is pushed up by the fuel pressure of the accumulated oil sump 61 and the injection hole (not shown)
Is released. As a result, the high-pressure fuel near the oil reservoir 61 and the injection hole gushes from the injection hole at a stretch, and starts injection.

Next, when the injection of the solenoid 67 is stopped when the injection is to be stopped, although it is for a short time,
Since the residual magnetism remains, a slight attractive force (Fr) acts on the valve 63 due to the residual magnetism. At this time, the seat portion 66 of the valve 63 is unseated, and the high-pressure port 58 and the drain port 56 communicate with each other. However, the communication time and the valve shift amount are extremely small, and the high-pressure port 58 is restricted. Due to the resistance 62, the pressure drop starts near the seat portion 66 with a certain delay. Accordingly, although the seat portion 66 is unseated, considerable hydraulic pressure is still maintained in the vicinity of the seat portion 66, and therefore, the pressure receiving area of the hydraulic pressure acting on the lower chamber 71 and the seat portion 66. Due to the difference, a hydraulic force acting on the valve 63 to push the valve 63 downward is applied.

Therefore, when the energization of the solenoid 67 is stopped, the downward force F ₂ applied to the valve 63 is expressed by the following equation. That is, F ₂ = (force of spring 65) + (pressure of back pressure chamber 57) × {(diameter dr of balance rod 68) ² − (diameter ds of seat portion 66) ² } × π / 4-Fr , The pressure of the back pressure chamber 57 during injection is set to 1000 kgf / cm.
² , the force of the spring 65 is 5 kgf, the diameter dr of the balance rod 68 is 3 mm, and the diameter ds of the seat portion 66 is 2.9 mm.
Then, F ₂ = 5 + 1000 × {(0.3) ² − (0.29) ² } × π / 4-Fr} (5 + 4.6) kgf−Fr

As described above, a force for pushing down the valve 63 is generated, for example, at 4.6 kgf.
9.6 kgf superimposed on the spring force of 5 kgf of the valve 6
3, the response delay due to the residual magnetism of the solenoid 67 can be greatly reduced as compared with the related art even if Fr due to the residual magnetism of the solenoid 67 acts in reverse.

In the second embodiment, as in the first embodiment, the diameter dr of the balance rod 68 is selected so that the hydraulic force acts in the direction opposite to the suction force of the solenoid 67. Is what you do. In the first embodiment, the inner valve seat diameter ds is made larger than the balance rod diameter dr, whereas in the second embodiment, the valve seat diameter ds is made smaller than the balance rod diameter dr. The operation and effect can be obtained. Of course,
By increasing the hydraulic force by increasing the diameter dr of the balance rod 68, the spring can be omitted as in the first embodiment.

In each of the first and second embodiments, the diameter of the balance rod is appropriately selected to minimize the hydraulic acting force applied to the valve to the attraction force due to the residual magnetism of the solenoid. Therefore, unlike a hydraulic control valve using a valve that does not use a balance rod, an increase in the size of the solenoid can be avoided at the same time.

[0035]

According to the first to fourth aspects of the present invention, the diameter of the balance rod and the diameter of the valve seat are selected such that the hydraulic force acting on the valve acts in the opposite direction to the suction force of the solenoid. Therefore, after stopping the energization of the solenoid, the combined force of the spring force of the spring and the above-mentioned hydraulic action force overcomes the attraction force of the valve due to residual magnetism, and the valve moves quickly downward. The delay in response due to the residual magnetism can be greatly reduced, and therefore, highly accurate metering can be performed up to a minute injection amount. Also, since the hydraulic force is kept to a minimum necessary to cancel the attractive force of the residual magnetism of the solenoid, unlike a hydraulic control valve using a valve that does not use a balance rod, the solenoid becomes larger. Can also be avoided at the same time.

In the solenoid-operated hydraulic control valve according to the fifth aspect, since the spring is eliminated, the cost can be reduced by reducing the number of components.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of the present invention.

FIG. 2 is a time chart for explaining the operation of the first embodiment.

FIG. 3 is a sectional view showing a second embodiment of the present invention.

FIG. 4 is a vertical sectional front view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Three-way valve type solenoid drive hydraulic control valve 17 ... Outer valve (first valve) 18, 65 ... Spring 19, 68 ... Balance rod 21 ... Inner valve seat 22 ... Inner valve (second valve) 50 ... Two-way valve type Solenoid-driven hydraulic control valve 63 ... valve 66 ... seat 71 ... lower chamber

Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) F02M 51/00 F02M 47/00

Claims (4)

(57) [Claims] A first valve which is driven to be sucked by a solenoid to communicate and cut off a hydraulic pressure generated by a pump, and has a spring for urging the first valve in a direction opposite to a suction force of the solenoid; A solenoid-operated hydraulic control valve comprising: a second valve having a valve seat at a lower portion slidably fitted into a hole provided in the first valve; A balance rod opposed to the second valve via a space to which hydraulic pressure is supplied in the hole is slidably fitted and provided below the second valve .
By making the diameter of the valve seat larger than the diameter of the balance rod when the first valve is seated on the second valve, the first valve can be connected to the second valve.
The valve seat and the balun
Depending on the size of the rods,
The pressure receiving area of the first valve is on the valve seat side
Slide the balance rod opposite to it
Towards the side is increased, whereby the hydraulic force acting on the said first valve is a solenoid driven pressure control valve, characterized in that the suction force of the solenoid were to act in the opposite direction. 2. The solenoid-operated hydraulic control valve according to claim 1, wherein the solenoid-operated hydraulic control valve is a three-way valve. 3. A solenoid driven valve having a spring driven by a solenoid to communicate and cut off hydraulic pressure generated by a pump and biasing the valve in a direction opposite to the suction force of the solenoid. In the hydraulic control valve, the solenoid-driven hydraulic control valve is a two-way valve, and in a hole provided in the valve having a seat portion at a lower portion,
A balance rod is slidably fitted and provided, and a lower chamber formed by the lower surface of the balance rod and the hole communicates with the vicinity of the seat portion through a communication passage, and hydraulic pressure passes through the communication passage. By acting on the lower surface of the balance rod and the lower chamber, the diameter of the balance rod is made larger than the diameter of the seat portion, so that the valve is separated from the seat portion by a solenoid, and is moved to the lower chamber.
Until the supplied hydraulic pressure starts a pressure drop with a certain delay
Was supplied to the lower chamber for a predetermined period of time.
Hydraulic by the solenoid driving hydraulic control valve the hydraulic acting force, characterized in that it has to act in the opposite direction to the attraction force of the solenoid to the valve. 4. The apparatus according to claim 1, wherein said spring is omitted.
Item 4. The solenoid-operated hydraulic control valve according to any one of Items 3 to 3.