JP2000179733A - Electro magnetically driven intake/exhaust valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an increase of power consumption, and prevent mechanical interference between adjacent devices by suppressing the increase of a size and a weight of an engine to the minimum. SOLUTION: A valve stem 3a of a valve 3 is energized to a valve closing side by a valve spring 5. A movable plate 12 being brought into continuously contact with the valve stem 3a is energized to a valve opening side by an upper spring 14. The movable plate 12 is attracted to the valve opening side and the valve closing side by a valve opening side electromagnet 9 and a valve closing side electromagnet 10 disposed opposing to both surfaces of the movable plate 12, and thereby, the valve 3 is opened/closed. Since the upper spring 14 and the valve spring 5 are formed by coil springs whose winding directions are reverse to each other, force around the valve stem 3a generated by motion of a valve stem direction of the movable plate 12 are canceled mutually, and wasteful power consumption is reduced without generating movement around the valve stem 3a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetically driven intake / exhaust valve device suitable for use as an intake or exhaust valve of an internal combustion engine, and more particularly to an electromagnetically driven intake / exhaust valve employing a coil spring as a biasing means for a movable portion. It relates to a valve device.

[0002]

2. Description of the Related Art Hitherto, there has been proposed a configuration in which an intake / exhaust valve of an internal combustion engine is driven electrically instead of a cam drive which is currently the mainstream. According to the configuration in which the intake and exhaust valves are electrically driven, the rotation mechanism such as the camshaft can be omitted, and the valve timing can be easily changed. The timing can be set arbitrarily, and the output characteristics and the fuel consumption characteristics can be improved.

[0003] As an electric drive device for the intake and exhaust valves, a configuration using an electromagnetic actuator using an electromagnet has been proposed. The configuration of this device is described in, for example,
No. 44716. The actuator having this configuration has two springs, one for biasing the movable part in the valve opening direction and the other for biasing the movable part in the valve closing direction. And two electromagnets that attract in the valve closing direction.

In this case, the movable system including the movable portion and the valve is in a neutral position separated from the attraction surface of the two electromagnets by a predetermined position by the spring force of the two springs when no current is flowing through the electromagnet. When an electric current is applied to one of the electromagnets on the valve-opening side or the valve-closing side, the attraction force overcomes the spring force of the spring and is attracted to the other electromagnet side due to the electromagnetic attraction force generated at that time. Will be.

When the current of the electromagnet is cut off in this state, the movable system once passes through the neutral position and approaches the other electromagnet due to the spring force of the spring. At this time, if a current flows through the other electromagnet, the movable system is attracted to the other electromagnet.

In this manner, the movable portion can be displaced by a predetermined displacement width in accordance with the current supply and cutoff operations of the two electromagnets, and this displacement is utilized to determine whether the valve is open or closed. Is switching.

[0007]

In the above-mentioned conventional electromagnetically driven intake / exhaust valve device, the coil spring for urging the movable portion toward the valve opening side and the coil spring for urging the movable portion toward the valve closing side are the same. Because the parts were used, the winding direction of these coil springs was the same, so the force in the rotation direction around the axis when one of the coil springs was extended by the movement of the movable part in the valve axis direction, The force in the direction of rotation about the axis when the other coil spring contracts is in the same direction, and a rotational motion about the valve axis occurs on the movable plate.

This phenomenon will be described in detail with reference to FIG. 6, the upper end surface 1 of the valve spring 101
01a has a clockwise force 1 according to the downward movement
25, and a counter-clockwise force 126 is produced following the upward movement. Similarly, a clockwise force 123 is generated on the lower end surface 102a of the upper spring 102 according to the downward movement 121, and a counterclockwise force 124 is generated along the upward movement 122.

Therefore, when the movable plate (not shown) moves downward 121, the lower end surface 102a of the upper spring 102
And the clockwise force 125 generated on the upper end surface 101a of the valve spring 101 is in the same direction, so that the movable plate is rotated clockwise, and when the movable plate moves upward 122, Since the counterclockwise force 124 generated on the lower end surface 102a of the upper spring 102 and the counterclockwise force 126 generated on the upper end surface 101a of the valve spring 101 are in the same direction, the movable plate is rotated counterclockwise, and In accordance with the up and down movement of the plate, the movable plate makes a right and left rotation around the valve axis in a plan view, and the attractive force of the electromagnet is consumed for useless rotation.

[0010] This rotational motion does not contribute to the valve opening or closing operation in the valve axis direction at all.
Since the direction of the rotational movement generated at the time of the valve opening operation is opposite to the direction of the rotational movement generated at the time of the valve closing operation, wasteful energy is drawn from the electromagnet, and the power consumption of the electromagnetically driven intake and exhaust valve device is reduced. There was a problem of increasing.

When a multi-valve system is used to improve the intake and exhaust efficiency of the engine, dimensional restrictions are strict in the arrangement direction of the cylinders, and the shape of the electromagnet and the movable plate of the electromagnetically driven intake and exhaust valve device is changed in the valve axis direction. It is necessary to make the rectangle not a circle in a plan view but a rectangle short in the cylinder arrangement direction.

In the case where the shape of the electromagnet and the movable plate is rectangular as described above, if the movable plate undergoes a rotational movement in the valve axis direction, the area where the movable plate and the electromagnet face each other, that is, the effective suction area decreases, and the attraction force decreases. Occurs. In order to compensate for the decrease in the attraction force, it is necessary to increase the current value of the electromagnet, and there is a problem that the power consumption of the electromagnetically driven intake and exhaust valve device increases.

Further, in order to prevent mechanical interference between the electromagnetically driven intake and exhaust valve devices adjacent to each other due to the rotation of the movable plate having a rectangular shape in a plan view, the clearance between the electromagnetically driven intake and exhaust valve devices is set large. In addition to the necessity of providing a partition wall and a partition wall, the size and weight of the engine are increased, and the mountability to a vehicle is deteriorated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an electromagnetically driven intake / exhaust valve device which prevents an increase in power consumption. It is also an object of the present invention to provide an electromagnetically driven intake and exhaust valve device that minimizes the increase in size and weight of the engine and prevents mechanical interference between adjacent devices.

[0015]

According to the first aspect of the present invention, a movable plate connected to each valve shaft of an intake valve or an exhaust valve and two working surfaces of the movable plate are provided. Two electromagnets disposed opposite to each other, first biasing means for biasing the movable portion that is the valve shaft or the movable plate toward the valve opening side, and biasing the movable portion toward the valve closing side. Second biasing means,
In an electromagnetically driven intake / exhaust valve device in which the intake valve or the exhaust valve is electromagnetically opened and closed in cooperation with these electromagnets and urging means, the first urging means and the second urging means Are formed by coil springs whose winding directions are opposite to each other.

According to a second aspect of the present invention, in the electromagnetically driven intake / exhaust valve device according to the first aspect, the number of turns and the material of each coil spring as the first and second urging means are the same. Make a summary.

According to a third aspect of the present invention, there is provided the electromagnetically driven intake / exhaust valve device according to the first or second aspect.
The gist is that a member that abuts each end of each coil spring, which is the second urging means, is provided with a projection that locks the rotation of the urging means with respect to the member.

According to a fourth aspect of the present invention, in the electromagnetically driven intake / exhaust valve device according to any one of the first to third aspects, the first and second biasing means include the electromagnet and the electromagnet. The gist is that it is arranged between the valve.

[0019]

According to the first aspect of the present invention, a movable plate connected to each valve shaft of an intake valve or an exhaust valve, and two movable plates disposed opposite to both working surfaces of the movable plate. A first for urging an electromagnet and a movable portion that is the valve shaft or the movable plate toward a valve opening side;
, And second biasing means for biasing the movable portion toward the valve closing side, and electromagnetically open and close the intake valve or the exhaust valve by cooperation of the electromagnet and the biasing means. In such an electromagnetically driven intake / exhaust valve device, the first urging means and the second urging means are formed by coil springs whose winding directions are opposite to each other, so that the movable portion slides in the valve axis direction. In this case, the rotational force exerted by one of the coil springs and the rotational force exerted by the other coil spring are opposite to each other and cancel each other. This has the effect of reducing the power consumption of the electromagnet for movement and preventing interference between adjacent electromagnetically driven intake and exhaust valve devices.

According to the second aspect of the present invention, first aspect is provided.
In addition to the effects of the invention described above, since the number of turns and the material of the coil springs as the first and second urging means are the same, one of the coil springs exerts when the movable portion slides in the valve axis direction. Since the force in the rotation direction and the force in the rotation direction exerted by the other coil spring are opposite to each other and have the same magnitude and almost completely cancel each other, the rotational movement of the movable portion can be further suppressed, and It is possible to reduce power consumption of the electromagnet and prevent interference between adjacent electromagnetically driven intake and exhaust valve devices.

According to the third aspect of the present invention, the first aspect is provided.
Alternatively, in addition to the effect of the invention described in claim 2, the member that comes into contact with each end of the coil spring as the first and second urging means is associated with rotation of the urging means with respect to the member. By providing the stopping projection, without depending on the unstable frictional force at the end of the coil spring,
The rotational force applied to the movable plate by these coil springs can be equalized.

According to the present invention described in claim 4, according to claim 1,
In addition to the effects of the invention according to any one of claims 3 to 3, the first and second biasing means are disposed between the electromagnet and the valve, so that one bias is provided. When the means is extended, the other urging means can enter the vacant space by being compressed, so that the space height for disposing these urging means is reduced, and the height of the engine is further reduced. Therefore, the mountability on a vehicle can be improved.

[0023]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a configuration of a first embodiment of an electromagnetically driven intake / exhaust valve device 1 according to the present invention, and FIG. 2 is an enlarged view of a main part of the first embodiment.
In the following description, an intake valve or an exhaust valve will be simply referred to as a valve.

In FIG. 1, an electromagnetically driven intake / exhaust valve device 1 is shown.
Is a cylinder head 2 of the engine, a valve 3, a valve retainer 4, a valve spring 5 which is a coil spring on a valve closing side as an urging means, housings 6, 7, 8 of the apparatus, an electromagnet 9 on a valve opening side, a valve closing. A side electromagnet 10, a shaft 11, a movable plate 12, a spring seat 13, an upper spring 14 which is a valve-opening coil spring as a biasing means, and a spring cover 15 are provided.

The valve shaft 3a of the valve 3 is
The valve guide 2a is slidable up and down inside a cylindrical valve guide 2a embedded in the valve guide 2a. A valve retainer 4 is fixed to the valve shaft 3a. A valve spring 5 is mounted in a compressed state between the valve retainer 4 and the cylinder head 2, so that the valve 3 is urged in a direction to close the port 2b of the cylinder head 2 (a valve closing direction). .

The housings 6, 7, and 8 of the apparatus are fixed to the cylinder head 2. A valve-opening electromagnet 9 and a valve-closing electromagnet 10 are provided in the housing. The electromagnets 9 and 10 are directly fixed and installed on the housings 6 and 8.

Each of the electromagnets 9 and 10 has an electromagnetic coil 9
a, 10a are provided, and the respective electromagnetic coils 9a, 10a
A drive current is supplied to a from a drive circuit (not shown). In this case, the attraction surfaces 9b and 10b of the electromagnet generate an attraction force. At the center of the electromagnets 9 and 10, a shaft 11 connected to the valve shaft 3a is installed so as to be slidable in the valve axis direction. A movable plate 12 made of a soft magnetic material is fixed to an intermediate portion of the shaft 11.

A spring seat 13 is fixed to an end of the shaft 11 opposite to the cylinder head 2, and a spring is provided between the shaft 11 and a spring cover 15 fixed to the housing. The shaft 11 is urged in the valve opening direction by the action of a certain upper spring 14.

The shaft 11 is provided coaxially with the valve shaft 3 b of the valve 3.
The end on the side faces the top surface 3c of the valve shaft 3a. Therefore, when a force in the valve opening direction (downward in the figure) acts on the shaft 11, the shaft 11 pushes the valve 3 to open the valve 3, and conversely, the shaft 11 moves in the valve closing direction (upward in the figure). In this case, the valve 3 is mounted on the valve seat 2c.
, And is displaced in the valve closing direction until the port 2b is closed. Thus, the valve 3 can be opened and closed by the attraction operation of the electromagnets 9 and 10.

The upper spring 14, which is a first urging means for urging the movable part toward the valve opening side, and the valve spring 5, which is a second urging means for urging the movable part toward the valve closing side, The winding directions are opposite to each other. Furthermore, upper spring 1
It is preferable that the specifications such as the number of turns and the material of the valve spring 5 and the valve spring 5 be the same except for the winding direction.

Thus, the direction of the rotational force that the upper spring 14 exerts on the movable plate 12 in the valve axis direction,
The directions of the rotational force exerted by the valve spring 5 on the movable plate 12 around the valve axis direction are opposite to each other, and cancel each other.

FIG. 2 is an enlarged view of a main part of the present embodiment.
FIG. 4 shows the valve spring 5 and the upper spring 14 in an enlarged manner, and also shows a force around the valve axis generated according to the movement of the movable plate in the valve axis direction.

As shown in FIG. 2, a counterclockwise force 23 is generated on the lower end surface 14a of the upper spring 14 in accordance with the downward movement 21 and a clockwise force 24 is generated in accordance with the upward movement 22. Conversely, a clockwise force 25 is generated on the upper end surface 5a of the valve spring 5 in accordance with the downward movement and a counterclockwise force 26 is generated in accordance with the upward movement.

Therefore, when the movable plate (not shown) moves downward 21, the counterclockwise force 23 generated on the lower end surface 14 a of the upper spring 14 and the clockwise force 25 generated on the upper end surface 5 a of the valve spring 5 cancel each other. When the movable plate moves upward 22, the clockwise force 24 generated on the lower end surface 14a of the upper spring 14 and the counterclockwise force 26 generated on the upper end surface 5a of the valve spring 5 cancel each other. As a result, the movement of the movable plate around the valve axis is reduced, and the attraction force of the electromagnet is less likely to be consumed by useless movement.

Further, if the winding direction and the material of the upper spring 14 and the valve spring 5 are opposite to each other and the number of windings and the material are the same, the magnitudes of the mutually canceling forces become equal, and the valve shaft of the movable plate Offset the forces that occur around you,
The rotational movement of the movable plate is suppressed, and the attraction force of the electromagnet is not consumed by useless movement.

FIG. 3 is an enlarged side view of a main part of the second embodiment. The configuration of the electromagnetically driven intake / exhaust valve device as a whole is as follows.
This is almost the same as the embodiment, but is different in that projections for locking the rotations of the springs 5 and 14 are provided on members that contact the respective ends of the valve spring 5 and the upper spring 14.

That is, in FIG.
The lower surface 5b of the valve spring 5 contacts the lower surface 5b of the valve spring 5.
A rotation stop 2d, which is a projection that locks the rotation of the lens, is provided. On the surface (lower surface) of the valve retainer 4 facing the valve spring 5, the upper end 5 of the valve spring 5 is provided.
A rotation stopper 4a, which is a projection that stops rotation of the valve spring 5 by abutting on c, is provided.

Similarly, a detent 13a is provided on the upper surface of the spring seat 13 opposite to the upper spring 14, which is a projection which abuts on the lower end portion 14b of the upper spring 14 and locks the rotation of the upper spring 14. . An upper end 14c of the upper spring 14 is provided on an inner surface of the spring cover 15 facing the upper spring 14.
Is provided with a rotation stopper 15a which is a projection that locks the rotation of the upper spring 14 by abutting the rotation of the upper spring 14.

These detents 2d, 4a, 13a, 1
5a, the valve spring 5 and the upper spring 1
4 does not slip relative to the respective spring receiving surfaces and does not rotate relatively, so that the magnitude of the rotational force applied to the movable plate 12 by the valve spring 5 and the upper spring 14. Therefore, the differences can be eliminated more accurately.

FIG. 4 is a longitudinal sectional view showing the structure of a third embodiment of the electromagnetically driven intake / exhaust valve device 51 according to the present invention.
FIG. 5 is an enlarged view of a main part of the third embodiment.

In FIG. 4, an electromagnetically driven intake / exhaust valve device 51 is shown.
Is a cylinder head 2 of the engine, a valve 3, a valve retainer 4, a valve spring 5 which is a coil spring on a valve closing side as an urging means, housings 6, 7, 8 of the apparatus, an electromagnet 9 on a valve opening side, a valve closing. A side electromagnet 10, a shaft 11, a movable plate 12, a spring seat 13, and an upper spring 14 which is a valve-opening coil spring as a biasing unit are provided.

The difference between the third embodiment shown in FIG. 4 and the first embodiment shown in FIG. 1 is that the upper spring 14, which is a coil spring for urging the movable portion toward the valve opening side, has two electromagnets 9,
10 and is accommodated inside the cylinder head 2. Accordingly, the position of the spring seat 13 is also moved downward, and the spring cover 15 used in the first embodiment is not required. Other configurations and operations are the same as those of the first embodiment.

The upper spring 14 is a first urging means for urging the movable part toward the valve opening side, and the valve spring 5 is a second urging means for urging the movable part toward the valve closing side. Have opposite winding directions. Further, it is preferable that the upper spring 14 and the valve spring 5 have the same specifications such as the number of windings and the material other than the winding direction.

Thus, the direction of the rotational force that the upper spring 14 exerts on the movable plate 12 in the valve axis direction,
The directions of the rotational force exerted by the valve spring 5 on the movable plate 12 around the valve axis direction are opposite to each other, and cancel each other.

Further, if the winding direction and the material of the upper spring 14 and the valve spring 5 are opposite to each other and the number of windings and the material are the same, the magnitudes of the mutually canceling forces become equal, and the valve shaft of the movable plate Offset the forces that occur around you,
The rotational movement of the movable plate is suppressed, and the attraction force of the electromagnet is not consumed by useless movement.

According to the configuration of the present embodiment, the upper spring 14 and the valve spring 5 are
By disposing the upper spring 14 and the valve spring 5 when one of the springs is extended, the other spring can be compressed to enter the empty space. It is possible to reduce the height of the space for disposition, further reduce the height of the engine, and improve the mountability on a vehicle.

FIG. 5 is an enlarged side view of a main part of the fourth embodiment. The configuration of the entire electromagnetically driven intake / exhaust valve device is the third
This is almost the same as the embodiment, but is different in that projections for locking the rotations of the springs 5 and 14 are provided on members that contact the respective ends of the valve spring 5 and the upper spring 14.

That is, in FIG.
The lower surface 5b of the valve spring 5 contacts the lower surface 5b of the valve spring 5.
A rotation stop 2d, which is a projection that locks the rotation of the lens, is provided. On the surface (lower surface) of the valve retainer 4 facing the valve spring 5, the upper end 5 of the valve spring 5 is provided.
A rotation stopper 4a, which is a projection that stops rotation of the valve spring 5 by abutting on c, is provided.

Similarly, on the upper surface of the spring seat 13 facing the upper spring 14, there is provided a rotation stopper 13 a which is a projection which abuts on the lower end portion 14 b of the upper spring 14 to lock the rotation of the upper spring 14. . On the surface of the housing 6 facing the upper spring 14, there is provided a rotation stopper 6 a which is a projection which abuts on the upper end portion 14 c of the upper spring 14 to lock the rotation of the upper spring 14.

These detents 2d, 4a, 13a, 6
a, the valve spring 5 and the upper spring 14
Of the valve spring 5 and the upper spring 1 do not rotate relative to the respective spring receiving surfaces and do not rotate relative to each other.
The magnitude of the rotational force applied to the movable plate 12 by the movable member 12 does not change, and the rotational force can be more accurately offset.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the configuration of a first embodiment of an electromagnetically driven intake / exhaust valve device according to the present invention.

FIG. 2 is an enlarged side view of a main part of the first embodiment.

FIG. 3 is an enlarged side view of a main part of the second embodiment.

FIG. 4 is a longitudinal sectional view showing a configuration of a third embodiment.

FIG. 5 is an enlarged side view of a main part of a fourth embodiment.

FIG. 6 is a diagram illustrating a problem of a conventional electromagnetically driven intake / exhaust valve device.

[Description of Signs] 1 electromagnetically driven intake / exhaust valve device 2 cylinder head 3 valve 4 valve retainer 5 valve spring 6, 7, 8 housing 9 valve-opening electromagnet 10 valve-closing electromagnet 11 shaft 12 movable plate 13 spring seat 14 upper side Spring 15 Spring cover

Claims (4)

[Claims] 1. A movable plate connected to each valve shaft of an intake valve or an exhaust valve, and a movable plate disposed opposite to both working surfaces of the movable plate.
Two electromagnets, a first urging means for urging the movable part which is the valve shaft or the movable plate toward the valve opening side, and a second urging means for urging the movable part toward the valve closing side. An electromagnetically driven intake / exhaust valve device, wherein the intake valve or the exhaust valve is electromagnetically opened / closed in cooperation with these electromagnets and biasing means, wherein the first biasing means and the second biasing are provided. The electromagnetically driven intake and exhaust valve device is characterized in that the means and the means are formed by coil springs whose winding directions are opposite to each other. 2. The electromagnetically driven intake / exhaust valve device according to claim 1, wherein the number of turns and the material of the first and second urging means are the same. 3. A member that abuts each end of each coil spring as the first and second urging means,
3. The electromagnetically driven intake / exhaust valve device according to claim 1, wherein a projection for locking rotation of the urging means with respect to the member is provided. 4. The apparatus according to claim 1, wherein each of the coil springs as the first and second urging means is disposed between the electromagnet and the valve. 2. The electromagnetically driven intake and exhaust valve device according to claim 1.