JPH1122431A - Control device for solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce seating impact at the time of valve closing by small electric power on a solenoid valve to open and close a valve supported at an intermediate position by two elastic bodies by electromagnetic force of two solenoids arranged against each other. SOLUTION: This control device makes a small electric current IT1 flow to a coil of a second solenoid 12 only for a previously specified period of time after a previously specified value of time passes after making an electric current flowing to a coil of a first solenoid 11 on the opening size zero. Thereafter, an electric current IT2 larger than IT1 is made to flow only for a previously specified period of time so as to settle bouncing, and when bouncing is settled and a valve is perfectly seated, a holding electric current IT3 is made to flow.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve control device for opening and closing a valve supported at an intermediate position by two elastic members by using electromagnetic force of two opposed solenoids. .

[0002]

2. Description of the Related Art A valve held between a fully-closed position and a fully-opened position by a closing-side spring biasing in a closing direction and an opening-side spring biasing in an opening direction is provided by two opposed solenoids. 2. Description of the Related Art Electromagnetic valves have been developed in which a valve is opened and closed by moving it using electromagnetic force. And
In the apparatus disclosed in Japanese Patent Application Laid-Open No. 8-135416, not only the closing solenoid but also the opening solenoid is energized during the valve closing operation in order to gently seat the valve body at the fully closed position. To reduce the impact when sitting (see FIG. 9).

[0003]

However, in the apparatus disclosed in the above publication, current flows through the open solenoid in addition to the close solenoid, but as the valve body approaches the fully closed position, the open solenoid and the Since the distance of the armature receiving the electromagnetic force is long, it is necessary to supply a large current to the opening-side solenoid in order to control the movement of the valve body with the opening-side solenoid, and there is a problem that power consumption is further increased. The present invention has been made in view of the above problems, and has as its object to provide a control device capable of reducing an impact when a solenoid valve of the above type is seated without consuming large electric power.

[0004]

According to the first aspect of the present invention, the valve body is held at an intermediate position by the closing elastic member biasing in the closing direction and the opening elastic member biasing in the opening direction. To
A solenoid valve control device that opens and closes a valve by moving it by the electromagnetic force of a closing solenoid and an opening solenoid that are opposed to each other. When the valve is closed, a current having a different magnitude is applied to the closing solenoid in multiple stages. A control device is provided in which the current is not supplied to the opening side solenoid. In the control device configured in this manner, the closing-side elastic body that urges in the closing direction, and the valve body that is held between the closed position and the open position by the opening-side elastic body that urges in the opening direction,
When the valve is opened and closed by moving the solenoid by the electromagnetic force of the closing solenoid and the opening solenoid that are opposed to each other, a current having a different size flows through the closing solenoid in a plurality of stages, and the current flows through the opening solenoid. No current flows.

According to the second aspect of the present invention, in the first aspect of the present invention, a drawing current for drawing the valve to the fully closed position at a low speed is first passed through the closing solenoid, and thereafter, the rebound of the valve is suppressed. Therefore, there is provided a control device in which a bounce suppressing current larger than the drawing current is caused to flow. In the control device configured as described above, the valve body held between the closed position and the open position by the closing-side elastic body biasing in the closing direction and the opening-side elastic body biasing in the opening direction are opposed to each other. When the valve is opened and closed by moving by the electromagnetic force of the arranged closed solenoid and the open solenoid,
At first, a drawing current for drawing the valve to the fully closed position at a low speed is supplied to the closing solenoid, and then a rebound suppressing current larger than the drawing current is supplied to suppress the rebound of the valve. No current flows.

According to a third aspect of the present invention, in the first aspect of the present invention, a rebound amount detecting means for detecting a rebound amount of the valve is provided, and the rebound suppressing current is changed according to the rebound amount detected by the rebound amount detecting means. A control device is provided which is adapted to move. In the control device configured as described above, the valve body held between the closed position and the open position by the closing-side elastic body biasing in the closing direction and the opening-side elastic body biasing in the opening direction are opposed to each other. When the valve is opened and closed by being moved by the electromagnetic force of the disposed closing solenoid and the opening solenoid, a drawing current is first passed through the closing solenoid to draw the valve to the fully closed position at a low speed. ,afterwards,
A bounce suppression current larger than the attraction current is passed, but the magnitude is changed according to the bounce amount detected by the bounce amount detection means.

[0007]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a solenoid valve according to the present invention applied to an intake valve of an automobile engine. In FIG. 1, reference numeral 1 denotes a cylinder head of an engine, and an intake valve 4 is arranged so as to open and close an opening 3 on a combustion chamber side of an intake port 2 of the cylinder head 1. The intake valve 4 has a valve shaft 5 supported by the cylinder head 1 via a valve guide 6, and a spring retainer 7 is attached to the top of the valve shaft 5, and the spring retainer 7 applies the spring force of the first spring 8. As a result, the intake valve 4 is constantly biased to the closed side.

Reference numeral 9 denotes a solenoid supporting member which is fixed to the cylinder head 1 and has a cavity 10 formed in a central portion. A first solenoid 11 and a second solenoid 12 are attached to the solenoid support member 9. The first solenoid 11 includes a coil 11a and a core member 11b, and the second solenoid 12 includes a coil 12a.
And a core member 12b, and holes 11c and 12c are formed in the respective central portions.

Reference numeral 13 denotes a valve pressing member, which includes a shaft 14 passing through the holes 11c and 12c of the first solenoid 11 and the second solenoid 12, a spring receiver 15 attached to the outer end of the shaft 14, and a solenoid support member. 9 attached to the middle portion of the shaft 14 so as to be within the central cavity of the first
An armature 16 receives the magnetic force of the solenoid 11 and the second solenoid 12.

A spring support member 17 is mounted outside the solenoid support member 9, and a spring stopper 18 having a spring receiver 19 is mounted on the spring support member 17.
A second spring 20 is disposed between the valve pressing member 13 and the second spring 20, and the second spring 20 urges the valve pressing member 13 in the opening direction.

Reference numeral 30 denotes an electronic control unit (hereinafter referred to as an ECU). The ECU 30 comprises a digital computer, and has input interfaces 31 and C connected to each other.
A PU 32, a RAM 33, a ROM 34, and an output interface 35 are provided. The CPU 32 is input from an engine speed sensor 41, a throttle opening sensor 42, a crank angle sensor 43, a reference position signal generator 44 for generating a reference position signal at the compression top dead center of the # 1 cylinder, and the like via the input interface 31. Based on the signal indicating the operating state, a signal for performing opening / closing control of the valve is generated by performing a calculation described later.

The signal is sent from the output interface 35 to the driver unit 36, and the driver unit 36 receives a signal sent from the output interface 35 from the power supply 37 to the coil 11 of the first solenoid 11.
a, The current flowing through the coil 12a of the second solenoid 12 is controlled. In the present embodiment, although there is no camshaft, although not shown, the reference position signal generator 44 uses a disk that is rotated once by two rotations of the crankshaft. The detection of the crank angle is performed based on signals from the reference position signal generator 44 and the crank angle sensor 43.
Any known method may be used and has no bearing on the essence of the present invention, so that the details are omitted.

Next, the basic operation of the valve in the first embodiment of the present invention configured as described above will be described. FIG. 1 shows the first solenoid 11.
No current is supplied to either the coil 11a of the second solenoid 12 or the coil 12a of the second solenoid 12, and the valve 4 is in the state between the fully closed state and the fully closed state, that is, the neutral state. Even in this state, the first spring 8 and the second spring 20 are compressed and generate urging forces, respectively, but they are in a neutral state because their magnitudes are equal.

When the coil 11a of the first solenoid 11 is energized from the neutral state, the first solenoid 11 generates an electromagnetic force, and the armature 16 of the valve pushing member 13 is attracted to the first solenoid 11 so that the valve pushing member 13 is moved. As a result, the valve 4 is pushed downward by the valve pushing member 13. Then, the valve 4 reaches the fully open position shown by the broken line. During this time, the first spring 8 is compressed, so that the first spring 8 continues to exert a force to return the valve 4 in the closing direction. On the other hand, the second spring 20 moves the valve 4 in the opening direction.
Continue to apply the force to press. That is, the second spring 20 is set so as to always exert a force for pushing the valve 4 in the opening direction.

In the fully opened state, the first spring 8 is strongly compressed, so that the urging force of the first spring 8 toward the closing side is large, but the second spring 20 has a reduced degree of compression. The biasing force to the opening side by 20 is small. Therefore, to maintain the fully open state,
It is necessary to keep energizing the coil 11a of the first solenoid 11.

When the current flowing through the coil 11a of the first solenoid 11 is cut from the fully opened state, the first spring 8
Is greater than the biasing force of the second spring 20 toward the open side, the valve 4 moves to the closing side, but closes beyond the neutral position due to the biasing force of the first spring 8. Reach to the side. When the coil 12a of the second solenoid 12 is energized, the second solenoid 12 generates an electromagnetic force, and the armature 16 of the valve pressing member 13 is attracted to the second solenoid 12 so that the valve pressing member 1
3 moves upward in the figure while compressing the second spring 20. As a result, the valve 4 is pushed upward in the drawing by the urging force of the first spring 8, and as shown by the dotted line, hits the valve seat 3a of the opening 3 of the intake port 2 and closes the opening 3 to the fully closed position. Reach

In the fully closed state, the second spring 20
Is strongly compressed, so that the urging force of the second spring 20 toward the open side is large. However, since the degree of compression of the first spring 8 is reduced, the urging force of the first spring 8 toward the closing side is small. Therefore, to maintain the fully closed state,
It is necessary to keep energizing the coil 12a of the second solenoid 12.

The basic operation of the valve mechanism has been described above. In the present invention, among the operations described above, the present invention is intended to reduce the impact when the valve 4 hits the valve seat 3a of the opening 3 of the intake port 2. Is what you do. FIG. 2 is a time chart for explaining the concept. 2A shows the displacement of the valve 4, FIG. 2B shows the change in the current flowing through the first solenoid 11 for opening the valve, and FIG. 2C shows the change in the second solenoid 12 for closing the valve.
3 shows a change in the current flowing through the circuit.

[0019] The first solenoid 11 at time t0 the current IH that was opened held from IH ₀ to 0. Then, as described above, the valve 4 moves to the closing side beyond the neutral point by the urging force of the first spring 8. Then, at time t when a predetermined time Dt2 elapses from time t1
Up to 2, electric current IT ₁ to the second solenoid 12. Here, the time t1 is a predetermined time Dt from the time t0.
1 has elapsed, and Dt is set such that the momentum of the urging force of the first spring 8 remains at time t1.
1 is obtained by experiment and stored.

Further, since it takes time the valve 4 to a large rebound velocity when attracting the valve seat 3a in the valve 4 increases the convergence, the magnitude of the time Dt2 current IT _1, the valve 4
Find the appropriate value from the experiment so that the person sits at a low speed. However, as described above, the time Dt2 and the current IT
_{Even if} the size of ₁ is appropriately set and the valve 4 is seated on the valve seat 3a at a low speed, the valve 4 rebounds and does not become fully closed at once.

[0021] Therefore, to t3 a predetermined time Dt3 a predetermined time t2 has passed, electric current ₂ for pressing the rebound to the second solenoid 12. Where I
Accelerate the convergence of the rebound by the magnitude of T ₂ to a value greater than IT _1. Dt3, IT ₂ also stored in search of optimum values by experiment, respectively. Time t3
Thereafter, the holding current IT ₃ required to hold the valve 4 in a closed position, flow to the start of the opening operation (not shown).

The control according to the present invention for weakening the impact when the valve 4 hits the valve seat 3a of the opening 3 of the intake port 2 has been described above. Next, the control of the entire intake valve will be described. As an example, if the intake valve is 15 ° CA before exhaust top dead center
The # 1 cylinder of a four-cylinder engine that opens at 50 ° CA after bottom dead center of intake will be described. FIG. 3 is a diagram showing the opening and closing of the intake valve set as described above when the compression top dead center of the # 1 cylinder is 0 ° CA. The portion indicated by A in FIG. 3 is a portion where the control for weakening the impact is performed. On the other hand, a portion indicated by B in FIG. 3 is a portion for opening a valve that has been closed, and in this embodiment, although not particularly implemented, the above-described control is performed. In addition, the behavior of the valve near the fully open position can be stabilized.

FIG. 4 is a flowchart of a main routine for controlling the entire intake valve shown in FIG. 3, and this routine is executed every time a reference position signal is issued. When the reference position signal is issued (step 1), a timer for counting the crank angle is started (step 2). When a predetermined crank angle is reached after the reference position, in this case, 165 ° CA after the reference position (= exhaust top dead) 15 ° before the point
CA) (step 3), the intake valve opening control is executed (step 4), and 590 ° CA after the reference position.
When (= 50 ° CA after intake bottom dead center) is reached (step 5), the above-described valve closing control for weakening the seating impact is executed (step 6), and the processing is ended.

The intake valve opening control in step 4 of the flow chart of FIG. 4 only involves turning on the power supply to the coil 11a of the first solenoid 11 from OFF to ON and turning off the power supply to the coil 12a of the second solenoid 12 from ON to OFF. Therefore, it is not specifically shown. Step 6 in the flowchart of FIG.
Is a control for weakening the above-mentioned impact, and is performed by a subroutine shown in FIG.

In the flowchart of FIG. 5, the current IH flowing through the coil 11a of the first solenoid 11 is set to 0 in step 51, and the timer is started in step 52. Step 53 the value of the timer current flow IT ₁ to the coil 12a of the second solenoid 12 in step 54 waiting to reach Dt1. Then, increasing the value of the current flowing through waiting for the value of the timer reaches Dt1 + Dt2 the coil 12a of the second solenoid 12 in step 56 at step 55 to IT _2. Then, further, the value of the timer at step 57 is, if reached Dt1 + Dt2 + Dt3, the value of the electric current applied to the coil 12a of the second solenoid 12 in step 58 in IT _3, and exit clear the timer in step 59.

FIG. 6 shows a second embodiment of the present invention.
FIG. 3 is a diagram showing a configuration of a state, in which a rebound amount of a valve 4 is detected.
Only the point where the valve position detection sensor 45 for adding
1 is different from the first embodiment shown in FIG.
This is the same as the embodiment. And the first embodiment
The current IT, which was a constant value in the description of _TwoTo
Change according to the value detected by the valve position detection sensor 45.
You.

FIG. 7 is a flowchart of the control according to the second embodiment. In step 71, the current IH flowing through the coil 11a of the first solenoid 11 is set to 0 as in step 51 of the flowchart in FIG.
Next, to detect the valve position x in step 72, if reaches a predetermined value x ₁ which valve position x is predetermined in step 73, the coil 1 of the second solenoid 12 in step 74
Flowing a predetermined current IT ₁ to 2a.

Then, in step 75, the valve position x is
If reaches a predetermined value x ₂ a predetermined showing the seating to detect the bounce amount H in step 77. Here, the rebound amount H is the amount of movement of the valve from x ₂ , that is, H = x
It is a -x _2. Next, at step 78, it is determined whether or not H is smaller than a predetermined threshold value Ha. If the determination is affirmative, at step 79, the coil 12 of the second solenoid 12 is determined.
and the value of the current flowing through the a in IT ₃ finished, if it is negative, the current IT proportional to the bounce amount H in step 80
The flow returns to step 77 by flowing (H), and the processing is repeated until an affirmative determination is made in step 78. FIG. 8 is a diagram illustrating the relationship between the current IT (H) flowing in step 80 and the rebound amount H.

As described above, in the first and second embodiments, by controlling the current flowing through the coil 12a of the second solenoid 12 on the closed side, the impact of seating can be reduced. It is not necessary to supply a current to the coil 11a of the first solenoid 11 on the opening side. On the other hand, in the device of the above-mentioned publication, as shown in FIG. 9, current is supplied to the solenoid on the open side even when the valve is closed, and current is supplied to the solenoid on the closed side even when the valve is opened. .

[0030]

According to the invention described in each of the claims, when the valve is closed, a large amount of electric power is required because current only needs to flow through the solenoid on the closing side and there is no need to flow current through the solenoid on the opening side. The impact at the time of seating of the valve can be softened and the seating noise can be reduced without using it.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a first exemplary embodiment of the present invention.

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

FIG. 3 is a diagram illustrating control of an intake valve according to the present invention.

FIG. 4 is a flowchart of a main routine for controlling an intake valve according to the present invention.

FIG. 5 is a flowchart of a control routine according to the first embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a second exemplary embodiment of the present invention.

FIG. 7 is a flowchart of a control routine according to a second embodiment of the present invention.

FIG. 8 is a diagram showing a relationship between a rebound amount of a valve and a current for suppressing the rebound amount.

FIG. 9 is a diagram showing a current flowing through a closing solenoid and an opening solenoid for opening and closing a valve in the prior art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Cylinder head 3a ... Valve seat 4 ... Intake valve 5 ... Valve shaft 8 ... 1st spring 11 ... 1st solenoid 11a ... Coil 12 ... 2nd solenoid 12 12a ... Coil 13 ... Valve pushing member 30 ... Electronic control unit (ECU) 36) Driver unit 37 ... Power supply 41 ... Engine speed sensor 42 ... Throttle opening sensor 43 ... Crank angle sensor 44 ... Reference position signal generator

Claims (3)

[Claims] A valve, which is held at an intermediate position between a closing-side elastic body that urges in a closing direction and an opening-side elastic body that urges in an opening direction, is provided with a closing solenoid and an opening solenoid that are opposed to each other. A solenoid valve control device that opens and closes the valve by moving it by electromagnetic force.When the valve is closed, a current of different magnitude flows through the closing solenoid in multiple stages, and the current flows through the opening solenoid. A control device characterized by not flowing. 2. The method according to claim 1, wherein a drawing current for drawing the valve to the closed position at a low speed is first supplied to the closing solenoid, and then a repulsion suppressing current larger than the drawing current is supplied for suppressing the rebound of the valve. The control device according to claim 1. 3. The control according to claim 2, further comprising a rebound amount detecting means for detecting a rebound amount of the valve, wherein the rebound suppressing current is changed according to the rebound amount detected by the rebound amount detecting means. apparatus.