JP2000146004A - Solenoid driving valve and valve driving device furnished with solenoid driving valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the power saving by reducing the loss following to the eddy current of an armature. SOLUTION: A solenoid driving valve 10 has a valve element 12. An armature 30 is connected to the valve element 12. At the upper side and the lower side of the armature 30, an upper coil 32 and a lower coil 36 are provided. The upper coil 32 is held to an upper core 34, while the lower coil 36 is held to a lower core 38. An exciting current is fed to the upper coil 32 and the lower coil 36 alternately. As a result, the armature 30 and the valve element 12 are driven to open and close. The directions of the exciting currents of the coils are set to make the magnetic fluxes generated to the coils pass in the reverse directions in the armature 30.

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 a valve driving apparatus provided with the electromagnetically driven valve, and more particularly to an armature connected to a valve body and electromagnetic coils disposed on both sides of the armature. The present invention relates to an electromagnetically driven valve and a valve driving device including a plurality of such electromagnetically driven valves.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Patent Laid-Open No. 9-13301
No. 0 and JP-A-9-303599,
2. Description of the Related Art An electromagnetically driven valve including a valve body functioning as an intake valve or an exhaust valve of an internal combustion engine is known. The electromagnetically driven valve has an armature connected to a valve body, first and second electromagnetic coils respectively disposed above and below the armature, and first and second electromagnetic coils holding the first and second electromagnetic coils, respectively. A spring is provided for biasing the core and the valve body toward the neutral position.

In the above-described conventional electromagnetically driven valve, when no exciting current is supplied to any of the electromagnetic coils, the valve body and the armature are held at a neutral position by a spring. Also, when the exciting current is supplied to the first electromagnetic coil, the valve element and the armature are attracted toward the first core. On the other hand, when the exciting current is supplied to the second electromagnetic coil, the valve element and the armature are supplied. The armature is aspirated toward the second core. Therefore, according to the above-described conventional electromagnetically driven valve, the valve element can be opened and closed by supplying an appropriate excitation current to the first and second electromagnetic coils alternately.

[0004]

In the above-described conventional electromagnetically driven valve, the exciting current supplied to the first electromagnetic coil is stopped, for example, in a state where the armature is attracted to the first core, or When an exciting current is supplied in a direction opposite to that of the armature, the armature starts to be displaced toward the second core in a state where closed-loop residual magnetism (closed-loop magnetic flux) is generated therein. In this case, when the direction of the magnetic flux generated when the exciting current is supplied to the second electromagnetic coil next matches the direction of the closed loop magnetic flux at the portion of the armature on the second core side, the magnetic flux density inside the armature Increases locally. As a result, a large eddy current is generated in the armature, so that the exciting current to be supplied to the second electromagnetic coil to attract the armature to the second core increases.

As described above, in the conventional electromagnetically driven valve, the effect of the closed loop magnetic flux generated in the armature causes
Depending on the direction of the magnetic flux generated by each electromagnetic coil, power consumption may increase. However, in the above-described conventional electromagnetically driven valve, such a problem is not taken into consideration, and the direction of the magnetic flux generated by each electromagnetic coil is not considered at all.

The present invention has been made in view of the above points, and provides an electromagnetically driven valve capable of saving power by appropriately setting the direction of magnetic flux generated by each electromagnetic coil. The first purpose is to do so. A second object of the present invention is to further reduce the power consumption of the electromagnetically driven valve in the valve driving device including a plurality of the aforementioned electromagnetically driven valves.

[0007]

The first object of the present invention is to provide an armature connected to a valve body as described in claim 1;
First and second arms respectively disposed on both sides of the armature
, And first and second cores respectively holding the first and second electromagnetic coils, and the first electromagnetic coil receives the exciting current to supply the armature to the first armature. The second electromagnetic coil generates a first magnetic flux to be attracted to the electromagnetic core, and the second electromagnetic coil attracts the armature to the second core by supplying an exciting current.
An electromagnetically driven valve that generates magnetic fluxes of the first and second electromagnetic coils such that the first magnetic flux and the second magnetic flux pass through the armature in opposite directions to each other. This is achieved by an electromagnetically driven valve that sets the direction of the current.

According to the first aspect of the present invention, when the supply of the exciting current to the first electromagnetic coil is stopped, a magnetic flux in a direction opposite to the first magnetic flux is generated. Due to the magnetic flux in the opposite direction, the first electromagnetic coil side
Magnetic flux (closed loop magnetic flux) circulating in the direction opposite to that of the first magnetic flux on the second electromagnetic coil side in the same direction as the first magnetic flux.
Occurs. In such a situation, when an exciting current is supplied to the second electromagnetic coil, a second magnetic flux in a direction opposite to the first magnetic flux is generated. Therefore, in the portion of the armature on the side of the second electromagnetic coil, the closed loop magnetic flux and the second magnetic flux are in opposite directions, so that the magnetic flux density inside the armature is reduced. As a result, the eddy current generated inside the armature is suppressed. Similarly, even when the excitation current is supplied to the first electromagnetic coil after the supply of the excitation current to the second electromagnetic coil is stopped, the eddy current generated inside the armature is suppressed. Therefore, according to the present invention, the excitation current to be supplied to each electromagnetic coil is reduced by reducing the loss associated with the eddy current in the armature.

The first object is to provide an electromagnetically driven valve according to the first aspect, wherein the first core generates a magnetic flux in the same direction as the first magnetic flux. An electromagnetically driven valve with a first permanent magnet, wherein the second core is provided with a second permanent magnet that generates a magnetic flux in the same direction as the second magnetic flux, is more effectively achieved.

In the invention described in claim 2, the first permanent magnet and the second permanent magnet generate magnetic fluxes in the same direction as the first magnetic flux and the second magnetic flux, respectively. Therefore, the exciting current to be supplied to the first electromagnetic coil and the second electromagnetic coil in order to attract the armature is reduced. In addition, the second object is, as described in claim 3, in a valve drive device including a plurality of electromagnetically driven valves in close proximity to each other, wherein the plurality of electromagnetically driven valves are connected to two adjacent electromagnetically driven valves. In the electromagnetically driven valve, the first magnetic flux and the second magnetic flux are disposed so as to be in the same direction at the outer peripheral side portions of the first electromagnetic coil and the second magnetic coil, respectively. This is achieved by an improved valve drive.

According to the third aspect of the present invention, the plurality of electromagnetically driven valves provided in the valve driving device are such that, in two adjacent electromagnetically driven valves, the first magnetic flux and the second magnetic flux are respectively different from each other. The first electromagnet and the second electromagnet are arranged so as to be in the same direction at the outer peripheral portion. For this reason, the first and second magnetic fluxes leaking from one adjacent electromagnetically driven valve to the other electromagnetically driven valve increase the first magnetic flux and the second magnetic flux of the other electromagnetically driven valve, respectively. Works. As a result, the exciting current to be supplied to the first and second electromagnetic coils of the electromagnetically driven valve is reduced.

[0012]

FIG. 1 is a sectional view of an electromagnetically driven valve 10 according to an embodiment of the present invention. As shown in FIG. 1, the electromagnetically driven valve 10 includes a valve body 12. The valve body 12 is a member that constitutes an intake valve or an exhaust valve of the internal combustion engine.
It is disposed in the cylinder head with the middle and lower ends exposed in the combustion chamber of the internal combustion engine. The cylinder head of the internal combustion engine is provided with a port having a valve seat for the valve element 12. The opening and closing of the port is controlled by the valve body 12 being separated from or seated from the valve seat. In this embodiment,
The internal combustion engine has a plurality of exhaust valves and intake valves in each cylinder, and an electromagnetically driven valve 10 is provided corresponding to each exhaust valve and each intake valve.

As shown in FIG. 1, the valve body 12 is connected to a valve shaft 14. The valve shaft 14 is held by a valve guide 16 so as to be displaceable in the axial direction. The valve guide 16 is
It is supported by the lower cap 17. Electromagnetic drive valve 10
Also has an armature shaft 18 that contacts the upper end of the valve shaft 14. The armature shaft 18 is a rod-shaped member made of a non-magnetic material. Valve shaft 14
A lower retainer 20 is fixed to the upper end of the lower case. A lower spring 22 is provided below the lower retainer 20. The lower end of the lower spring 22 is in contact with the lower cap 17. The lower spring 22 urges the lower retainer 20 and the armature shaft 18 upward in FIG.

An upper retainer 24 is fixed to the upper end of the armature shaft 18. Appari Retainer 2
Above 4, the lower end of the upper spring 26 is in contact. A cylindrical upper cap 27 is provided around the upper spring 26 so as to surround the outer periphery thereof. The upper end of the upper spring 26 is in contact with an adjustment bolt 28 screwed to the upper cap 27. The upper spring 26 urges the retainer 24 and the armature shaft 18 downward in FIG.

An armature 30 is joined to the outer periphery of the armature shaft 18. The armature 30 is a disk-shaped member made of a soft magnetic material. Armature 3
Above 0, an upper coil 32 and an upper core 34 are provided. Below the armature 30, a lower coil 36 and a lower core 38 are provided. The upper core 34 and the lower core 38 are both members made of a magnetic material, and have annular grooves 34 a and 38 a for accommodating the upper coil 32 and the lower coil 36, respectively, and through holes 34 b and 38 that penetrate through the central portion thereof in the axial direction.
b. Bearing members 40 and 42 are provided in the through holes 34b and 38b, respectively. The armature shaft 18 passes through the through holes 34b and 38b, and is slidably held by bearing members 40 and 42. The upper coil 32 and the lower coil 36 are connected to a drive circuit (not shown). The drive circuit supplies an exciting current to the upper coil 32 and the lower coil 36 at a predetermined timing.

An outer cylinder 44 is provided on the outer periphery of the upper core 34 and the lower core 38. The upper core 34 and the lower core 38 are held by an outer cylinder 44 so that a predetermined interval is secured between them. Further, the above-described upper cap 27 is fixed to the upper end surface of the upper core 34. The adjuster bolt 28 is attached to the armature 30
Is adjusted so that the neutral position is at the center between the upper core 34 and the lower core 38.

According to the above configuration, by supplying an exciting current to the upper coil 32, an upward electromagnetic attractive force can be applied to the armature 30. By supplying an exciting current to the lower coil 36, a downward electromagnetic attraction force can be applied to the armature 30. Accordingly, the armature 30 is reciprocated between the upper core 34 and the lower core 38 by supplying an exciting current to the upper coil 32 and the lower coil 36 at an appropriate timing alternately, that is, the valve body 12 is opened and closed. Can be.

Hereinafter, the operation of the electromagnetically driven valve 10 will be described in more detail with reference to FIGS. In the following description, the excitation current supplied to the upper coil 32 or the lower coil 36 for attracting and holding the armature 30 to the upper core 34 or the lower core 38 is referred to as “suction current”. Further, the magnetic flux generated when an attraction current is supplied to the upper coil 32 or the lower coil 36 is referred to as “attraction magnetic flux”.

FIGS. 2 to 7 show a state in which the armature 30 is in contact with the upper core 34 (that is, the valve body 12 is in the fully closed position) and a state in which the armature 30 is in contact with the lower core 38 (that is, the valve body). 12 is in the fully open position)
The position of the armature 30 at each point in the process of being displaced to the magnetic flux generated by the upper coil 32 and the lower coil 3
6 schematically shows the magnetic flux emitted by 6 and the residual magnetic flux generated in the armature 30. 2 to 7 show only the right half of the main part of the electromagnetically driven valve 10 in FIG. 2 to 7, the symbol “x” attached to the upper coil 32 or the lower coil 36 indicates a direction in which the exciting current goes from the front side to the back side of the drawing (that is, a counterclockwise direction when viewed from the top in the drawing; And the symbol "●" indicates the direction in which the exciting current goes from the back side to the front side (that is, clockwise as viewed from the top in the figure; hereinafter, referred to as the second direction). Represents flowing to

FIG. 2 shows that the armature 30 has an upper core 34.
(The position of the armature 30 in this state is hereinafter referred to as a valve closing position). In the state shown in FIG. 2, the attraction current in the first direction is supplied to the upper coil 32, so that the attracted magnetic flux circulates in a clockwise direction through the upper core 34 and the armature 30 so as to surround the upper coil 32. I do. The suction magnetic flux generates a suction force for holding the armature 30 at the valve closing position.

FIG. 3 shows a state in which the armature 30 is held at the valve closing position as described above, and an exciting current (hereinafter, referred to as an opening current) in a second direction opposite to the attraction current is supplied to the upper coil 32. It shows the state that was done. When the opening current in the second direction is supplied to the upper coil 32, the upper coil 32
The direction of the generated magnetic flux changes relatively gradually from the inside to the outside around the upper coil 32 with a delay with respect to the change in the exciting current. Therefore, after the exciting current supplied to the upper coil 32 is switched from the attraction current in the first direction to the opening current in the second direction, as shown in FIG. 3, the magnetic flux surrounds the upper coil 32.
On the inner side, the magnetic flux circulates counterclockwise in the figure, and on the outer side, the magnetic flux circulates clockwise in the figure. The magnetic flux passes through the inside of the armature 30 rightward in the drawing on the upper core 34 side and passes leftward in the drawing on the opposite side to the upper core 34. When the magnitudes of the magnetic fluxes in the opposite directions inside the armature 30 become substantially equal to each other and cancel each other, the upper core 34 and the armature 30
Is smaller than the urging force of the upper spring 26.

When the suction force acting between the upper core 34 and the armature 30 becomes smaller than the urging force of the upper spring 26, the armature 30
Starts to be displaced toward the lower core 38 due to the urging force of.
In this case, as described above, the armature 30 is separated from the upper core 34 in a state in which magnetic fluxes in opposite directions are circulated therein, as shown in FIG.
Inside 0, a closed loop magnetic flux circulating clockwise in the figure remains.

When the armature 30 is displaced to a predetermined position, an attraction current in the first direction is supplied to the lower coil 36, as shown in FIG. When the attraction current in the first direction is supplied to the lower coil 36, an attraction magnetic flux circulating clockwise in the drawing is generated so as to surround the lower coil 36. The attracted magnetic flux flows between the lower core 38 and the armature 30 so that the armature 30 has the lower core 3
A suction force in the direction toward 8 acts. The effect obtained by supplying the same current in the first direction to the lower coil 36 as in the upper coil 32 will be described later in detail. The above-described suction force acts on the armature 30, thereby compensating for energy loss due to sliding resistance and residual combustion pressure. The armature 30 passes through the state shown in FIG.
It is displaced until it comes into contact with the lower core 38 as shown in FIG.
Then, by maintaining the current supply to the lower core 38, the armature 30 is held at a position where the armature 30 is in contact with the lower core 38 (hereinafter, referred to as a fully open position of the armature 30).

Conversely, by supplying an opening current in the second direction to the lower coil 36 and then supplying an attraction current to the upper coil 32 at an appropriate timing, the armature 30 is fully closed from the fully open position. It can be displaced to a position. As described above, the electromagnetically driven valve 10 of the present embodiment is configured such that the attracted magnetic flux generated when the attractive current is supplied to the upper coil 32 and the attracted magnetic flux generated when the attractive current is supplied to the lower coil 36 are connected to the armature 30. By setting the direction of the attraction current supplied to the upper coil 32 and the lower coil 36 so as to pass in the opposite direction (that is, by supplying the attraction current in the same direction to the upper coil 32 and the lower coil 36). It is characterized by realizing power saving of 10. Hereinafter, the characteristics of the electromagnetically driven valve 10 will be described.

FIG. 8 shows a state in which the lower coil 36 is supplied with an attraction current in the second direction in FIG. 5 for comparison. The configuration in which the attraction currents in opposite directions are supplied to the upper coil 32 and the lower coil 36 in this manner is hereinafter referred to as a comparison configuration. As shown in FIG.
Is supplied with the attraction current in the second direction, the lower coil 3
6, attracted magnetic flux circulating in the counterclockwise direction in the figure. This attracted magnetic flux passes through the inside of the armature 30 to the left in the drawing. On the other hand, as described above, the closed loop magnetic flux circulating clockwise in the figure remains inside the armature 30, and the direction of the closed loop magnetic flux is as follows.
The armature 30 faces leftward in the figure on the lower core 38 side.

That is, in the state shown in FIG. 8, on the lower core 38 side of the armature 30, the direction of the closed loop magnetic flux and the direction of the attracted magnetic flux generated by the lower coil 36 match each other. For this reason, the attracted magnetic flux tends to flow intensively at the portion of the armature 30 on the lower core 38 side. In this case, the magnetic flux density locally increases inside the armature 30, and the eddy current generated in the armature 30 in the process of the armature 30 approaching the lower core 38 increases. Furthermore,
Since the direction of the attracted magnetic flux coincides with the direction of the closed loop magnetic flux on the lower core 38 side, the closed loop magnetic flux does not disappear immediately even if the attractive magnetic flux acts, but gradually disappears over a relatively long time. . Such a gradual change in the closed-loop magnetic flux also increases the eddy current generated in the armature 30.

Since the direction of the attracted magnetic flux coincides with the direction of the closed loop magnetic flux on the lower core 38 side of the armature 30, a part of the attracted magnetic flux flowing from the lower core 38 to the armature 30 becomes a part of the closed loop magnetic flux existing in the armature 30. And circulates inside the armature 30. In this case, the attractive magnetic flux that can contribute to generating the attractive force to the armature 30 decreases.

As described above, in the contrast configuration, the attracted magnetic flux generated by the upper coil 32 and the attracted magnetic flux generated by the lower coil 36 pass through the armature 30 in the same direction, so that a large eddy current is generated in the armature 30. Thus, the attracted magnetic flux generated by the lower coil 36 is not efficiently used as the magnetic flux for attracting the armature 30. For these reasons, the attraction current to be supplied to each coil increases in the contrast configuration.

On the other hand, in the present embodiment, as described above, since the attraction current in the same first direction as that of the upper coil 32 is supplied to the lower coil 36, the attraction magnetic fluxes generated by both coils cause the armature 30 to move in the opposite direction. Pass in the direction. Therefore, as shown in FIG. 6, the direction of the attracted magnetic flux generated by the lower coil 36 is opposite to the direction of the closed loop magnetic flux at the portion of the armature 30 on the lower core 38 side. As described above, since the attracted magnetic flux and the closed-loop magnetic flux are opposite to each other at the portion of the armature 30 on the lower core 38 side, a local increase in the magnetic flux density in the armature 30 is prevented, whereby the eddy current of the armature 30 is reduced. Is suppressed. Further, in this case, the eddy current of the armature 30 is also suppressed by preventing the change of the closed-loop magnetic flux over a long period of time by rapidly eliminating the closed-loop magnetic flux by the attracted magnetic flux. Further, since the attracted magnetic flux and the closed-loop magnetic flux are in opposite directions, the attracted magnetic flux flowing into the armature 30 from the lower core 38 returns to the lower core 38 without circulating inside the armature 30. That is, the attracted magnetic flux generated by the lower coil 36 is efficiently used as a magnetic flux for attracting the armature 30 to the lower core 38.

As described above, according to the present embodiment, the attracted magnetic flux can be effectively used as the magnetic flux for attracting the armature 30, and the eddy current generated in the armature 30 can be suppressed. Therefore, according to the electromagnetically driven valve 10 of the present embodiment, the attraction current to be supplied to the lower coil 36 can be reduced. FIG. 9 is a diagram showing the above-mentioned effect obtained by the electromagnetically driven valve 10 of the present embodiment, for example, in a case where the valve body 12 is driven from a fully closed position to a fully open position in a constant displacement pattern, in comparison with a comparative configuration. It is. In FIG.
(A) shows the displacement of the valve body 12 and (B) shows the lower coil 36.
(C) is a solid line for the electromagnetically driven valve 10 and a broken line for the comparison configuration, with the horizontal axis representing the time change of energy loss due to the eddy current of the armature 30 on the horizontal axis. Show.

As shown in FIG. 9 (C), according to the electromagnetically driven valve 10 of the present embodiment, it can be seen that the loss due to the eddy current is reduced as compared with the comparative configuration. In the present embodiment, in addition to the reduction of the eddy current loss, as described above, the attracted magnetic flux is efficiently used as the magnetic flux for attracting the armature 30, and as shown in FIG. The attraction current to be supplied to the lower coil 36 is reduced as compared with the configuration.
Further, for the same reason as described above, even when the valve body 12 is displaced from the fully open position to the fully closed position, the attraction current to be supplied to the upper coil 32 is reduced.

As described above, in the electromagnetically driven valve 10 of the present embodiment, the attraction current to be supplied to the lower coil 36 and the upper coil 32 for opening and closing the valve body 12 is reduced. Therefore, according to the present embodiment, power saving of the electromagnetically driven valve 10 can be achieved, and heat generation due to copper loss of each coil can be suppressed to be small. In the above embodiment, when the armature 30 is displaced from the fully closed position or the fully opened position, the upper coil 32 or the lower coil 36 is displaced.
It has been described that an open current is supplied to the armature 30 in a direction opposite to the attracting current, and a closed loop magnetic flux is generated in the armature 30 due to the effect of the open current. However, simply the upper coil 3
2 when the supply of the attraction current to the
Even if an open current is not supplied), a closed-loop magnetic flux is generated in the armature 30 as in the above-described embodiment.

FIG. 10 shows the magnetic flux generated after the attraction current in the first direction to the upper coil 32 is stopped. When the supply of the attraction current to the upper coil 32 is stopped, an eddy current is generated in the upper core 34 and the armature 30 accordingly. The eddy current generates a magnetic flux that reverses the direction of the magnetic flux surrounding the upper coil 32 sequentially from the inside to the outside. For this reason, when the supply of the attraction current to the upper coil 32 is stopped, the magnetic flux generated by the eddy current on the inner side moves counterclockwise in the drawing as shown in FIG. A state is formed in which the magnetic flux circulates and the remaining attracted magnetic flux circulates clockwise on the outside. Then, as these magnetic fluxes pass through the inside of the armature 30 in opposite directions, the armature 30 separates from the upper core 34 in a state where the closed loop magnetic flux remains in the armature 30 as in the case shown in FIG. become. Therefore, the above-described effect of the present embodiment can be obtained even when the open current in the opposite direction is not supplied to the upper coil 32 and the lower coil 36.

As described above, in this embodiment, the internal combustion engine has a plurality of exhaust valves and a plurality of intake valves in each cylinder, and the electromagnetically driven valve 1 corresponds to each exhaust valve and each intake valve.
0 is provided. That is, in this embodiment, a plurality of electromagnetically driven valves 10 are provided. FIG. 11 shows a cross-sectional view of a main part of two electromagnetically driven valves 10 adjacent to each other. In addition,
For convenience of explanation, the electromagnetically driven valve disposed on the left side in FIG. 11 is represented by reference numeral 10a, and the electromagnetically driven valve disposed on the right side is represented by reference numeral 10b.

In FIG. 11, the electromagnetically driven valve 10
The direction of the attraction current supplied to the upper coil 32 and the lower coil 36 of a and 10b is represented by a symbol “×” (first direction) or “●” (second direction), and the attraction magnetic flux generated by the attraction current is Indicated by arrows. As described above, in each of the electromagnetically driven valves 10a and 10b, the direction of the attraction current supplied to the upper coil 32 and the lower coil 36 is set so that the attraction magnetic flux generated by them passes through the inside of the armature 30 in the opposite direction. I have. In this embodiment,
Further, the attracted magnetic flux generated by the upper coils 32 of the electromagnetically driven valves 10a and 10b adjacent to each other and the lower coil 3
The direction of the attraction current supplied to each coil is set so that the attraction magnetic fluxes generated by the coils 6 are in the same direction at the portions adjacent to each other.

That is, in FIG. 11, the upper coil 32 and the lower coil 36 of the electromagnetically driven valves 10a and 10b are shown.
Are all supplied with the attraction current in the first direction,
The direction of the attracted magnetic flux on the outer peripheral side of the upper coil 32 of the upper core 34 included in the electromagnetically driven valve 10a, and the upper coil 3 of the upper core 34 included in the electromagnetically driven valve 10b
2, the direction of the attracted magnetic flux on the outer peripheral side is upward in the drawing, and the direction of the attracted magnetic flux on the outer peripheral side of the lower coil 36 of the lower core 38 included in the electromagnetically driven valve 10a, and the lower core included in the electromagnetically driven valve 10b. The direction of the attracted magnetic flux on the outer peripheral side of the lower coil 36 is upward in the drawing. For this reason, for example, FIG.
As shown by the dashed arrow in FIG. 3, the attracted magnetic flux generated by the lower coil 36 of the electromagnetically driven valve 10a
In the case of leakage to the side, this leakage magnetic flux also
The magnetic flux attracted by the lower 36b is increased, and the electromagnetically driven valve 10b contributes as a magnetic flux to draw the armature 30 toward the lower core 38.

As described above, in the present embodiment, the attracted magnetic flux generated by the upper coil 32 and the lower coil 36 of the adjacent electromagnetically driven valves 10a and 10b respectively
Since the directions of the attraction currents are set so as to be in the same direction at adjacent portions of a and 10b, the leakage magnetic flux from the adjacent electromagnetically driven valve causes the magnetic flux to attract the armature 30 at the electromagnetically driven valve. It is effectively used as For this reason, when the armature 30 is attracted to the upper core 30 or the lower core 38, it is possible to reduce the attraction current to be supplied to the upper coil 32 or the lower coil 36. Therefore, according to the present embodiment, each electromagnetically driven valve 10a,
10b, together with the fact that the attracted magnetic flux passing through the armature 30 is in the opposite direction, the electromagnetically driven valves 10a, 10b
It is possible to further reduce power consumption and heat generation of b.

Next, a second embodiment of the present invention will be described. FIG. 12 is a sectional view of a main part of the electromagnetically driven valve 100 of the present embodiment. 12, the same components as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted.
The electromagnetically driven valve 100 of the present embodiment includes an upper core 102 and a lower core 104 instead of the upper core 34 and the lower core 38 of the first embodiment. The upper core 102 has an annular slit 106 that connects the upper bottom surface in FIG. 11 and the annular groove 102a that houses the upper coil 32. An annular permanent magnet 108 is provided in the slit 106. Similarly, the lower core 104 includes an annular slit 110 that connects the lower bottom surface in FIG. 11 and an annular groove 104a that accommodates the lower coil 36. An annular permanent magnet 112 is provided in the slit 110. Permanent magnets 108 and 1
12 such that the magnetic fluxes generated by them are in the same direction as the attractive magnetic flux generated when the attractive current in the first direction is supplied to the upper coil 32 and the lower coil 36 (ie,
In the case shown in FIG. 12, the diameter of the permanent magnet 108 is set such that the outer peripheral side is an N pole and the inner circumferential side is an S pole, and the outer diameter of the permanent magnet 112 is an S pole and the inner circumferential side is an N pole. Polarized in the direction. Hereinafter, the permanent magnet 108
Or, the magnetic flux generated by 112 is referred to as an assist magnetic flux.

According to the above configuration, when the armature 30 reaches the vicinity of the upper core 34, as shown by an arrow in FIG.
Armature 3 from the pole to the outer periphery of lower core 104
The magnetic flux circulates in a direction to reach the S-pole through the zero and the inner peripheral side of the lower core 104 (that is, the same direction as the attracted magnetic flux generated by the upper coil 32). By the circulation of such magnetic flux,
A magnetic attraction force acts on the armature 30 so as to be attracted to the upper core 34. That is, the armature 30
In addition to the attractive force of the attraction magnetic flux generated by the upper coil 32, the attraction force of the assist magnetic flux generated by the permanent magnet 108 acts. Therefore, according to the electromagnetically driven valve 100, the attraction current to be supplied to the upper coil 32 in order to displace the armature 30 toward the fully closed position or to maintain the armature 30 at the fully closed position is reduced. Similarly, by the assist magnetic flux generated by the permanent magnet 112, the attraction current to be supplied to the lower coil 36 for displacing the armature 30 toward the fully open position or holding the armature 30 at the fully open position is also suppressed.

In the electromagnetically driven valve 100 of this embodiment,
Similarly to the electromagnetically driven valve 10 of the first embodiment, an attraction current in the first direction is supplied to the upper coil 32 and the lower coil 36. Therefore, the attractive magnetic flux generated by the upper coil 32 and the assist magnetic flux generated by the permanent magnet 108 and the attractive magnetic flux generated by the lower coil 36 and the assist magnetic flux generated by the permanent magnet 112 pass through the inside of the armature 30 in opposite directions. Thus, as described in the first embodiment, the power saving and low heat generation of the electromagnetically driven valve 100 are achieved.

In this embodiment, by providing the permanent magnets 108 and 112, the attraction current to be supplied to the upper coil 32 and the lower coil 36 can be reduced. Therefore, according to the present embodiment, it is possible to further reduce the power consumption and heat generation of the electromagnetically driven valve 100. FIG. 11 of the first embodiment.
As in the configuration shown in FIG.
00, the direction of the attracted magnetic flux generated by the upper coil 32 and the direction of the assist magnetic flux generated by the permanent magnet 108, and the attractive magnetic flux and the permanent magnetic flux 1 generated by the lower coil 36
Power saving and low heat generation of the electromagnetically driven valve 100 are also achieved by making the directions of the assist magnetic fluxes generated by 12 the same direction in adjacent portions.

In the above embodiment, the attraction current in the first direction is supplied to the upper coil 32 and the lower coil 36 of the electromagnetically driven valve 10. However, the direction of the current is reversed, and the second direction is supplied to each coil. May be supplied. In the first and second embodiments, the electromagnetically driven valve 1
Although a case has been described where 0 is applied to an exhaust valve and an intake valve of an internal combustion engine, the present invention is not limited to this, and can be applied as any other valve drive device.

[0043]

As described above, according to the first aspect of the present invention, the first armature is sucked by the first or second core.
Alternatively, the exciting current supplied to the second electromagnetic coil can be reduced. Therefore, according to the present invention, power saving and low heat generation of the electromagnetically driven valve can be achieved.

According to the second aspect of the present invention, the first
By providing the first and second permanent magnets on the second core and the second core, respectively, it is possible to further reduce power consumption and reduce heat generation of the electromagnetically driven valve. Further, according to the third aspect of the present invention, in a valve driving device including a plurality of electromagnetically driven valves, power saving and low heat generation of the electromagnetically driven valves can be effectively achieved.

[Brief description of the drawings]

FIG. 1 is an axial sectional view of an electromagnetically driven valve according to an embodiment of the present invention.

FIG. 2 is a diagram showing a state in which an attraction current is supplied to an upper coil.

FIG. 3 is a diagram illustrating a state in which an open current is supplied to an upper coil.

FIG. 4 is a diagram illustrating a state in which the armature is separated from an upper core in a state where a closed-loop magnetic flux is generated therein;

FIG. 5 is a diagram showing a state at the time when the supply of the attraction current to the lower coil is started.

FIG. 6 is a diagram showing a state in which the armature is attracted to the lower core side by the attracted magnetic flux of the lower coil.

FIG. 7 is a diagram illustrating a state in which the armature is in contact with the lower core.

FIG. 8 is a diagram showing a state in which an attraction current is supplied to a lower coil in a comparative configuration.

FIG. 9A is a diagram showing a displacement pattern of a valve body.
(B) is a diagram showing a change over time of an attraction current supplied to the lower coil in comparison with a comparison configuration. (C) is a diagram showing a time change of a loss due to an eddy current generated in the armature, as compared with a comparative configuration.

FIG. 10 is a diagram showing a magnetic flux generated after the supply of the attraction current to the upper coil is stopped.

FIG. 11 is a sectional view of a main part of two adjacent electromagnetically driven valves.

FIG. 12 is a sectional view of a main part of an electromagnetically driven valve according to a second embodiment of the present invention.

[Explanation of symbols]

 10, 100 electromagnetically driven valve 12 valve element 30 armature 32 upper coil 34, 102 upper core 36 lower coil 38, 104 lower core 108, 112 permanent magnet

Continued on the front page (72) Inventor Masahiko Asano 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Tatsuo Iida 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation F-term (reference 3H106 DA07 DA13 DA25 DA26 DB02 DB12 DB26 DB32 DC02 DC17 DD03 EE22 KK17

Claims (3)

[Claims] 1. An armature connected to a valve body, first and second electromagnetic coils respectively disposed on both sides of the armature, and first and second electromagnetic coils respectively holding the first and second electromagnetic coils. A second magnetic core, wherein the first electromagnetic coil generates a first magnetic flux for attracting the armature to the first electromagnetic core when an exciting current is supplied, and the second electromagnetic coil is An electromagnetically driven valve that generates a second magnetic flux that attracts the armature to the second core when an exciting current is supplied, wherein the first magnetic flux and the second magnetic flux form the armature. An electromagnetically driven valve, wherein directions of exciting currents supplied to the first and second electromagnetic coils are set so as to pass in opposite directions. 2. The electromagnetically driven valve according to claim 1, wherein the first core includes a first permanent magnet that generates a magnetic flux in the same direction as the first magnetic flux, and the second core includes: An electromagnetically driven valve, comprising: a second permanent magnet that generates a magnetic flux in the same direction as the second magnetic flux. 3. A valve driving device comprising a plurality of electromagnetically driven valves in proximity to each other according to claim 1 or 2, wherein the plurality of electromagnetically driven valves are adjacent to each other in the two electromagnetically driven valves, and the first magnetic fluxes are different from each other. And the second magnetic fluxes are respectively connected to the first electromagnetic coil and the second electromagnetic coil.
A valve driving device, which is arranged so as to be in the same direction as each other at a portion on the outer peripheral side of the electromagnetic coil.