JPH11132018A - Solenoid driven valve - Google Patents

Abstract

(57) Abstract: The present invention relates to an electromagnetically driven valve constituting an intake valve or an exhaust valve of an internal combustion engine, and has an object of realizing a function of effectively eliminating the influence of a collision reaction force with a simple structure. And An armature shaft (28) displaced integrally with a valve pair.
Is provided. The armature 44 is fixed to the armature shaft 28. An upper electromagnet 46 and a lower electromagnet 48 are provided above and below the armature 44. A pair of springs for urging the armature 44 to the neutral position is provided. Armature shaft 28
Is provided with a hollow portion 30. The steel ball 34, the first
The spring 36 and the second spring 38 are housed.
The armature 44 is connected to the upper electromagnet 46 or the lower electromagnet 4
8 is generated by the first spring 36 along with the relative displacement between the steel ball 34 and the armature shaft 28.
And the reaction force generated by the second spring 38 cancels out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetically driven valve, and more particularly to an electromagnetically driven valve suitable as a device constituting an intake valve or an exhaust valve of an internal combustion engine.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Application Laid-Open No. Hei 7-33543.
As disclosed in No. 7, an electromagnetically driven valve used as an intake valve or an exhaust valve of an internal combustion engine is known. The above-mentioned conventional electromagnetically driven valve has an armature displaced together with the valve pair, and a pair of electromagnets disposed to oppose the armature vertically.
A spring for biasing the armature to a neutral position.

In the above-described conventional electromagnetically driven valve, when no exciting current is supplied to any of the electromagnets, the armature and the valve pair can be held at a neutral position. In the above-mentioned conventional electromagnetically driven valve, if an appropriate exciting current is supplied to an electromagnet (hereinafter referred to as an upper electromagnet) disposed above the armature, the armature is attracted to the upper electromagnet and the valve pair is fully closed. Can be displaced. Furthermore,
According to the above-described conventional electromagnetically driven valve, if an appropriate exciting current is supplied to an electromagnet (hereinafter, referred to as a lower electromagnet) disposed below the armature, the armature is attracted to the lower electromagnet to bring the valve pair to the fully open position. Can be displaced. Therefore, according to the above-mentioned conventional electromagnetically driven valve, the valve pair is reciprocated between the fully open position and the fully closed position by supplying an exciting current to the upper electromagnet and the lower electromagnet alternately at an appropriate timing. Can be.

In the conventional electromagnetically driven valve, the armature collides with the upper electromagnet or the lower electromagnet when the valve pair reaches the fully open position or the fully closed position.
At this time, a force (hereinafter, referred to as a collision reaction force) acting on the armature to rebound the armature from the upper electromagnet or the lower electromagnet acts. In order to properly operate the above-mentioned conventional electromagnetically driven valve, it is necessary that the armature be attracted to the upper electromagnet or the lower electromagnet regardless of the occurrence of the collision reaction force.

The above-mentioned conventional electromagnetically driven valve has a function of changing the exciting current supplied to the electromagnet in accordance with the operating state of the electromagnetically driven valve. By changing the exciting current supplied to the electromagnet, the magnitude of the electromagnetic force acting between the electromagnet and the armature can be changed. Also,
By changing the electromagnetic force between the electromagnet and the armature, it is possible to suppress the collision reaction force and generate a large electromagnetic force that resists the collision reaction force. In this regard,
The method of controlling the exciting current supplied to the electromagnet is effective in appropriately operating the electromagnetically driven valve regardless of the collision reaction force.

[0006]

However, the magnitude of the collision reaction force acting on the armature changes according to the operating state of the electromagnetically driven valve. On the other hand, in order to operate the electromagnetically driven valve with low power consumption, it is desirable that the exciting current supplied to the electromagnet is suppressed to a necessary minimum. For this reason, it is not always easy to operate the electromagnetically driven valve properly by controlling the exciting current supplied to the electromagnet to eliminate the influence of the collision reaction force.

The present invention has been made in view of the above points, and has as its object to provide an electromagnetically driven valve having a simple structure and capable of effectively eliminating the influence of a collision reaction force. And

[0008]

The above object is achieved by the present invention.
An electromagnetically driven valve comprising: an armature; a pair of electromagnets disposed opposite to each other above and below the armature; and a pair of spring members for urging the armature toward a neutral position. A shaft member having a hollow portion extending in the direction, the shaft member being displaced together with the armature, an inertia member housed in the hollow portion, and a reaction force generating a reaction force for preventing a relative displacement between the shaft member and the inertia member. Generating means;
This is achieved by an electromagnetically driven valve having:

[0009] In the present invention, when the armature reaches the electromagnet, a collision reaction force is generated between the armature and the electromagnet, in which the armature rebounds from the electromagnet. At this time, a large deceleration occurs in the shaft member. When the deceleration acts on the shaft member, the inertia member housed inside the shaft member
Displaced relatively in the direction of the electromagnet inside the hollow portion. When a relative displacement of the inertial member toward the electromagnet occurs, a reaction force in a direction that hinders the relative displacement, that is, a reaction force for urging the shaft member toward the electromagnet, is transmitted to the shaft member. If the above-mentioned reaction force acts on the shaft member at the same time as the collision reaction force acts on the armature, the two cancel each other out, thereby preventing the armature from rebounding.

[0010]

FIG. 1 shows an overall configuration diagram of an electromagnetically driven valve 10 according to an embodiment of the present invention. Electromagnetic drive valve 10
Is provided with a valve body 12. The valve body 12 is used as an intake valve or an exhaust valve of an internal combustion engine. The valve element 12 is disposed on a cylinder head 14 of the internal combustion engine so as to be exposed in the combustion chamber. The port 16 is connected to the cylinder head 14.
Is provided. The port 16 is formed with a valve seat 18 for the valve element 12. The port 16 becomes conductive when the valve body 12 is separated from the valve seat 18, and
When the valve element 12 is seated on the valve seat 18, the valve element 12 enters a shut-off state.

A valve shaft 20 is fixed to the valve body 12. The valve shaft 20 is slidably held in the axial direction by a valve guide 22. The valve guide 22 is supported by the cylinder head 14. At the upper end of the valve shaft 20,
The lower retainer 24 is fixed. Lower retainer 24
A lower spring 26 is provided at the lower part of the lower part. The lower spring 26 urges the lower retainer 24 upward in FIG.

An armature shaft 28 is provided above the valve shaft 20. The armature shaft 28 is a cylindrical member made of a non-magnetic material. The armature shaft 28 is a main part of the electromagnetically driven valve 10 of the present embodiment. FIG. 2 shows a cross-sectional view of the armature shaft 28. As shown in FIG. 2, a hollow portion 30 is provided inside the armature shaft 28. Hollow part 3
0 extends in the axial direction of the armature shaft 28. A closing plug 32 for closing the hollow portion 28 is press-fitted into the upper end of the armature shaft 28.

A steel ball 34 is housed inside the hollow portion 30. Inside the hollow portion 30, a first spring 36 and a second spring 38 are disposed above and below the steel ball 34, respectively. The first spring 36 and the second spring 38 both have the same natural length and the same spring constant. In the steady state, the steel ball 34 is in the first position as shown in FIG.
It is held at a position of a predetermined length L0 from the upper end of the spring 36 and the lower end of the second spring 38, respectively. Hereinafter, this position is referred to as a neutral position of the steel ball 34.

As shown in FIG. 1, an upper retainer 40 is fixed to the upper end of the armature shaft 28. An upper spring 42 is provided above the upper retainer 40.
Are arranged. The upper spring 42 urges the upper retainer 40 downward in FIG. An annular armature 4 is provided around the armature shaft 28.
4 are joined. The armature 44 is made of a magnetic material. Above and below the armature 44, an upper electromagnet 46 and a lower electromagnet 48 are provided. The upper electromagnet 46 includes an upper coil 50 and an upper core 52.
It has. On the other hand, the lower electromagnet 48 is
4 and a lower core 56. Armature shaft 28
Is slidably held at the center of the upper core 52 and the lower core 56.

Hereinafter, the operation of the electromagnetically driven valve 10 will be described. In the electromagnetically driven valve 10, when an exciting current is supplied to the upper coil 50, a magnetic flux circulating inside and outside the upper coil 50 is generated. This magnetic flux returns through a path including the upper core 52 and the armature 44. At this time, an electromagnetic force is generated between the armature 44 and the upper electromagnet 46 to draw the armature 44 toward the upper electromagnet 46.

Therefore, according to the electromagnetically driven valve 10, by supplying an appropriate exciting current to the upper coil 50, the armature 44, the armature shaft 28, the valve body 12 and the like can be displaced toward the upper electromagnet 46 side. it can. The armature shaft 28 can be displaced toward the upper electromagnet 46 until the armature 44 collides with the upper core 52.
The valve element 12 closes the port 16 in a situation where the armature 44 contacts the upper core 52. Therefore, according to the electromagnetically driven valve 10, by supplying an appropriate exciting current to the upper coil 50, the valve body 12 can be fully closed.

When the valve body 12 is maintained in the fully closed state, the upper spring 42 and the lower spring 26
Biases the armature shaft 28 toward the neutral position. When the supply of the exciting current to the upper coil 50 is stopped in such a situation, the armature shaft 28 is thereafter displaced in the valve opening direction according to the spring force of the upper spring 42 and the lower spring 26.

According to the electromagnetically driven valve 10, the lower coil 54
By supplying an exciting current to the lower coil 54, it is possible to generate a magnetic flux that returns inside and outside the lower coil 54. Lower coil 5
The magnetic flux circulating inside and outside 4 flows through a path including the lower core 56 and the armature 44. At this time, the armature 44 is provided between the armature 44 and the lower electromagnet 48.
Is generated toward the lower electromagnet 48 side. Therefore, according to the electromagnetically driven valve 10, after the supply of the exciting current to the upper coil 50 is stopped, the exciting current is supplied to the lower coil 54 at an appropriate timing, so that the armature 44 collides with the lower electromagnet 48. Axis 28
Can be displaced.

The valve body 12 is fully opened when the armature 44 contacts the lower electromagnet 48. Therefore, according to the electromagnetically driven valve 10, after the supply of the excitation current to the upper coil 50 is stopped, the supply of the excitation current to the lower coil 54 is started at an appropriate timing, whereby the valve body 12 is fully opened from the fully closed state. State can be changed. When the supply of the exciting current to the lower coil 54 is stopped after the valve body 12 changes to the fully open state, the valve body 12
And the lower spring 22 starts to be displaced toward the fully closed position. Thereafter, when the excitation current is repeatedly supplied to the upper coil 50 and the lower coil 54 at appropriate timing, the valve element 12 can be opened and closed.

When the electromagnetically driven valve 10 according to the present embodiment operates, the armature 44 collides with the upper electromagnet 46 when the valve pair 12 reaches the fully closed position.
Similarly, in the electromagnetically driven valve 10, when the valve pair 12 reaches the fully open position, the armature 44 collides with the lower electromagnet 48. Armature 44 is upper electromagnet 4
6 or the lower electromagnet 48, between the armature 44 and the upper electromagnet 46, or between the armature 4 and the lower electromagnet 46.
A collision reaction force is generated between the armature 4 and the lower electromagnet 48 so as to rebound the armature 44. Therefore, in order to properly hold the valve pair 12 at the fully closed position or the fully open position, it is necessary to prevent the armature 44 from rebounding without being affected by the above-described collision reaction force.

In the electromagnetically driven valve 10 of the present embodiment, the steel ball 34, the first spring 36, and the second spring 38 built in the armature shaft 28 allow the valve pair 12 to reach the fully open position or the fully closed position. In this case, it is characterized in that a force for canceling the collision reaction force is generated. Hereinafter, the above-mentioned characteristic portions will be described with reference to FIGS. FIG.
Shows a state around the armature 44 when the valve pair 12 displaced from the fully closed position reaches the vicinity of the fully opened position. In the present embodiment, the electromagnetically driven valve 10 moves the armature 4 while the armature 44 reaches the lower electromagnet 48.
4 is controlled so as to appropriately decrease the displacement speed. Therefore, in the state shown in FIG. 3, the armature 44 and the armature shaft 28 are displaced toward the lower electromagnet 48 while decelerating at the deceleration G0.

When the deceleration G0 acts on the armature shaft 28 displaced toward the lower electromagnet 48, the steel ball 34
Inertia causes the first spring 36 to expand and the second
Attempt to reduce spring 38. In this case, as shown in FIG. 3, the steel ball 34 has a predetermined length Δ according to the deceleration G0.
The lower electromagnet 48 from the neutral position within the hollow portion 30 by L
Relative displacement to the side.

FIG. 4 shows the valve pair 1 displaced from the fully closed position.
2 shows a state around the armature 44 when the armature 2 reaches the fully open position. In this embodiment, the armature 44
When the valve pair 12 reaches the fully open position, the lower electromagnet 48
Collide with When the armature 44 collides with the lower electromagnet 48, a collision reaction force is generated between the armature 44 and the lower electromagnet 48 so as to make the armature 48 bounce.

For this reason, when the valve pair 12 reaches the fully open position, the armature 44 thereafter applies a large deceleration G1 and
A speed V toward the upper electromagnetic coil 46 (hereinafter, this speed is referred to as a rebound speed V) is generated. Armature 4
When the large deceleration G1 described above occurs in FIG.
Is largely displaced from the neutral position toward the lower electromagnet 48 side as shown in FIG. At this time, a large extension occurs in the first spring 36 according to the deceleration G1, while a large contraction occurs in the second spring 38 according to the deceleration G1.

In the state shown in FIG. 4, the first spring 36 and the second spring 38 generate an urging force for urging the steel ball 34 toward its neutral position. At this time, the armature shaft 28 is urged toward the lower electromagnet 48 by the reaction force, that is, in a direction in which the rebound speed V disappears. When the armature 44 collides with the lower electromagnet 48, the first spring 36 and the second spring 3
8 generates a reaction force in the direction of eliminating the rebound speed V as described above, the armature 44 from the lower electromagnet 48
Bounce is effectively prevented.

In the electromagnetically driven valve 10, when the armature 44 collides with the upper electromagnet 46, the first spring 36 and the second spring 38 operate in the same manner as the armature 44 collides with the lower electromagnet 48.
A repulsive force in a direction to make the rebound speed V disappear.
For this reason, according to the electromagnetically driven valve 10 of the present embodiment, it is possible to effectively prevent the armature 44 from rebounding during the operation of the electromagnetically driven valve 10.

In the above embodiment, the upper electromagnet 46 and the lower electromagnet 48 correspond to the "a pair of electromagnets" of the first embodiment, and the upper spring 42 and the lower spring 26 correspond to the "a pair of electromagnets" of the first embodiment. Spring member "
The armature shaft 28 is the "shaft member" according to claim 1, and the steel ball 34 is the "inertia member" according to claim 1.
In addition, the first spring 36 and the second spring 38 correspond to the "reaction force generating means" of the first aspect, respectively.

In the above embodiment, the first spring 36 and the second spring 38 generate a reaction force that hinders the relative displacement between the steel ball 34 and the armature shaft 28. The configuration for generating the force is not limited to this. That is, for example, by securing the inner diameter of the hollow portion 30 by a predetermined length larger than the outer diameter of the steel ball 34 and filling the hollow portion 30 with oil, a damper composed of oil and the steel ball 34 is formed. The above reaction force may be generated by a mechanism.

In the above embodiment, the steel ball 3
4. First spring 36 and second spring 38
Is incorporated in the armature shaft 28, but the present invention is not limited to this. If the steel ball 34 and the like are incorporated in a member displaced together with the armature 44, such as the valve shaft 20, for example. Good.

[0030]

As described above, according to the first aspect of the present invention, the inertial member and the reaction force generating means can generate a force for canceling the collision reaction force acting between the armature and the electromagnet. . For this reason, according to the electromagnetically driven valve of the present invention, a stable operating state can always be realized regardless of the occurrence of a collision reaction force.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an entire configuration of an electromagnetically driven valve according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of the electromagnetically driven valve of the embodiment.

FIG. 3 is a diagram illustrating a state realized when the armature reaches the vicinity of the lower electromagnet with the operation of the electromagnetically driven valve of the embodiment.

FIG. 4 is a diagram illustrating a state realized when the armature reaches the lower electromagnet with the operation of the electromagnetically driven valve according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Electromagnetic drive valve 12 Valve pair 26 Lower spring 28 Armature shaft 30 Hollow part 34 Steel ball 36 1st spring 38 2nd spring 42 Upper spring 44 Armature 46 Upper electromagnet 48 Lower electromagnet

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hiroyuki Hattori 1st Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation

Claims (1)

[Claims] 1. An electromagnetically driven valve comprising: an armature; a pair of electromagnets disposed above and below the armature; and a pair of spring members for urging the armature toward a neutral position. A shaft member having a hollow portion extending in the direction, the shaft member being displaced together with the armature, an inertia member housed in the hollow portion, and a reaction force generating a reaction force for preventing a relative displacement between the shaft member and the inertia member. An electromagnetically driven valve, comprising: generating means.