JPH09331664A - Rotary type electromagnetic actuator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease diametric dimension and perform miniaturization by providing a core member on an axial line of a rotary shaft, in a rotary type electromagnetic actuator turning the rotary shaft by a magnetic field generated in the core member and a magnet, by providing the core member in a position opposed to the magnet. SOLUTION: A core member 17 is arranged so as to be opposed to a pair of sector magnets provided in one side of a rotary shaft. This core member 17 is constituted by a cylindrical core 18, bar-shaped core 23 and a plate-shaped core 27. In a bar-shaped part 24 of the bar-shaped core 23, forward/reverse rotational coils are wound. By inputting a current to each of these coils, in a sector cover part 21 of the cylindrical core 18 and a sector cover part 25 of the bar-shaped core 23, a magnetic field of different polarity is generated. A magnetic path sectional area of the core member 17 can be almost fixed by a shape of each member, magnetic field leakage is suppressed, and responsiveness of turning action of the rotary shaft can be enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary electromagnetic actuator for setting a rotary shaft at a predetermined angle by controlling the duty ratio of pulse waves input to a forward rotating coil and a reverse rotating coil, and more particularly to an automobile. TECHNICAL FIELD The present invention relates to a rotary electromagnetic actuator suitable for use as an electronically controlled throttle valve, an idle speed control valve, etc. of a commercial engine.

[0002]

2. Description of the Related Art Generally, a rotary electromagnetic actuator according to the prior art has a rotating shaft, a magnet provided on the rotating shaft, a core member provided so as to face the magnet, and a winding member provided inside the core member. A magnetic field formed between the magnet and a positive rotation coil that is provided around the magnet and that rotates the rotation shaft in the normal direction by a magnetic field formed between the magnet and the magnet and that is wound around the core member. And a reverse rotation coil that reversely rotates the rotary shaft.

In this type of rotary electromagnetic actuator, a pulse wave that turns on and off at a constant cycle (frequency) is applied to the forward rotation coil and the reverse rotation coil, and the duty ratio of this pulse wave is changed. The rotation angle of the rotary shaft was adjusted.

Further, as the one using the rotary type electromagnetic actuator constructed as described above for the electronically controlled throttle valve, there are disclosed in Japanese Patent Laid-Open Nos. 5-149154 and 4-234.
539, JP-A-4-234540, etc., these electronically controlled throttle valves are configured such that the valve shaft of a throttle valve body is a rotary shaft of a rotary electromagnetic actuator.

In such an electrically controlled throttle valve, when the driver depresses the accelerator pedal, the operation amount is detected by an opening sensor such as a potentiometer on the accelerator side, and the valve opening by the throttle valve body is detected. The throttle valve element is opened and closed by the rotary electromagnetic actuator so that the valve opening degree corresponds to the accelerator operation amount. Further, in the electronically controlled throttle valve, the throttle valve body is provided with feedback control in accordance with the accelerator operation amount based on a throttle sensor such as a potentiometer for detecting the valve opening degree provided on the throttle valve side. The valve opening of is set according to the accelerator operation amount.

The adjustment of the valve opening of the throttle valve body is
This is done by changing the duty ratio of the pulse wave input to the forward rotation coil and the reverse rotation coil of the rotary electromagnetic actuator.

[0007]

In the rotary electromagnetic actuator according to the above-mentioned prior art, a magnet is attached to the valve shaft and a coil is wound around the outer circumference of the magnet, as disclosed in the above-mentioned publications. The core member is fixed to the case side. Therefore, the magnet and the core member must be arranged in the radial direction of the valve shaft, which causes a problem that the rotary electromagnetic actuator becomes large.

Further, when the rotary electromagnetic actuator is used as an electronically controlled throttle valve, an idle speed control valve, etc., each valve becomes large, and each valve is arranged in the engine room, so that the layout is limited. There is a problem that it will end up.

The present invention has been made in view of the above-mentioned problems of the prior art. In the present invention, since the core member around which the coil is wound is arranged in the axial direction of the rotating shaft so as to face the magnet, the size can be reduced. An object of the present invention is to provide a rotary electromagnetic actuator that can be designed.

[0010]

A rotary electromagnetic actuator according to the present invention comprises a rotary shaft, a magnet provided on the rotary shaft, a core member provided so as to face the magnet, and an inside of the core member. And a reverse rotation coil for rotating the rotation shaft forward and reverse by a magnetic field formed between the magnet and the magnet.

Then, in order to solve the above-mentioned problem,
A feature of the configuration adopted by the invention of claim 1 is that the core member is a tubular core formed as a tubular body having an opening on one side and a fan-shaped lid on the other side facing the magnet; A rod-shaped rod which is arranged in a cylindrical core, one side of which is a rod-shaped portion around which the forward rotation coil and the counter-rotation coil are wound, and the other side of which is a fan-shaped lid portion that is combined with the fan-shaped lid portion of the tubular core to face the magnet. A core and a plate-shaped core made of a disc-shaped body that is located between one end of the rod-shaped portion of the rod-shaped core and the opening of the tubular core and is arranged to cover the opening. It consists of.

With the above structure, since the core member forms one magnetic path by the cylindrical core, the rod-shaped core, and the plate-shaped core, a pulse wave having a predetermined cycle is input to the forward rotation coil and the reverse rotation coil. Then, magnetic flux flows through the core member, and different magnetic poles are generated between the fan-shaped lid portion of the cylindrical core and the fan-shaped lid portion of the rod-shaped core, which are both end portions of the core member, and a magnetic field is generated between the fan-shaped lid portions. To do. On the other hand, since the magnetic field is also generated from the magnet provided on the rotating shaft, the magnet causes attraction and repulsion by the magnetic field of the magnet and the magnetic field of the fan-shaped lid portion, and the rotating shaft rotates. Further, the magnetic field generated by the forward rotation coil flows from one fan-shaped lid portion to the other fan-shaped lid portion, and the magnetic field generated by the counter-rotation coil flows from the other fan-shaped lid portion to one fan-shaped lid portion. There is. Thereby, by controlling the duty ratio of the pulse wave input to each coil, it is possible to adjust the strength of the magnetic field generated from one fan-shaped lid portion of the core member and the strength of the magnetic field generated from the other fan-shaped lid portion, The rotating shaft to which the magnet facing the core member is fixed can be rotated and held at a predetermined angle.

In a second aspect of the present invention, the magnet is formed into a disc shape by a pair of fan-shaped magnets having different magnetization directions with respect to the core member, and the fan-shaped lid portion and the rod-shaped core of the core member of the tubular core are formed. The fan-shaped lid portion is formed in a fan-shaped body having different magnetization directions.

With the above configuration, in the pair of fan-shaped magnets, a magnetic field is constantly generated from one fan-shaped magnet having the surface of the N pole to the other fan-shaped magnet having the surface of the S-pole, and each fan-shaped magnet of the core member. A magnetic field corresponding to the duty ratio of the pulse wave input to the forward rotation coil and the reverse rotation coil is generated between the lid portions. The rotating shaft provided with the fan-shaped magnets is rotated by attraction and repulsion by the magnetic field generated between the fan-shaped lid portions of the core member and the magnetic field generated between the fan-shaped magnets. At this time, since the magnet and the fan-shaped lid are formed in a fan shape, the magnetic field generated from the magnet is always a magnetic field generated from one of the fan-shaped lids or a magnetic field generated between both the fan-shaped lids. On the other hand, it is possible to cause suction and repulsion.

According to the invention of claim 3, there is provided a slanted opening formed by cutting the tubular core from the fan-shaped lid toward the opening, and the wall thickness of the tubular core is directed from the opening to the fan-shaped lid. It is formed so that it gradually becomes thicker.

As described above, the cylindrical core prevents the magnetic flux from interfering with the rod-shaped core accommodated in the cylindrical core by the inclined opening to reduce magnetic leakage, and the wall thickness of the cylindrical core from the opening is fan-shaped. Since the thickness is gradually increased toward the lid, the magnetic path cross-sectional area can be made constant from the opening on one side to the fan-shaped lid on the other side. In addition, since the rod-shaped core forms a tapered surface from the rod-shaped portion toward the fan-shaped lid portion, the fan-shaped lid portion can be formed on the other side of the rod-shaped portion while maintaining the magnetic path cross-sectional area. Furthermore, since the plate-shaped core is formed in a conical shape that thickens from the outer circumference to the inner circumference, it is possible to cover between the cylindrical core and the rod-shaped core while maintaining the magnetic path cross-sectional area. Thereby, a magnetic path having a constant cross-sectional area with respect to the flow of the magnetic flux of the core member including the tubular core, the rod-shaped core, and the plate-shaped core can be secured, and the magnetic flux leakage generated in the core member is reduced.

According to the fourth aspect of the invention, the cylindrical core, the rod-shaped core, and the plate-shaped core forming the core member are formed of electromagnetic stainless steel.

With the above structure, the eddy current can be reduced, the drive current for generating the magnetic flux in the core member can be reduced, and the response speed can be increased. Further, it is possible to manufacture by cold forging.

According to the fifth aspect of the present invention, a plurality of slits that divide the outer peripheral surface at equal intervals are formed in the outer peripheral surface of the rod-shaped portion of the rod-shaped core in the axial direction.

With the above structure, the direction of the magnetic flux generated by the forward rotation coil and the direction of the magnetic flux generated by the reverse rotation coil are directly opposite to each other in the core member, and a pulse signal having a predetermined frequency is input to each coil, whereby the core member is The direction of the magnetic flux flowing through is alternately changed. Therefore, an eddy current is generated on the outer peripheral side of the core member. Therefore, a plurality of slits are formed on the outer peripheral surface of the rod-shaped portion of the rod-shaped core, and the eddy current on the outer peripheral side is reduced to a small eddy current to reduce energy due to the eddy current, thereby reducing leakage of magnetic flux.

According to the invention of claim 6, slits are formed in the radial direction in the fan-shaped lid portion of the cylindrical core and the fan-shaped lid portion of the rod-shaped core in the radial direction.

With the above structure, the eddy current generated on the surface of the fan-shaped lid portion can be reduced to a small eddy current to reduce the energy due to the eddy current and reduce leakage of magnetic flux.

[0023]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

An embodiment according to the present invention is shown in FIGS. 1 to 19, and in this embodiment, an electronically controlled throttle valve using a rotary electromagnetic actuator according to the present invention will be described as an example.

In the figure, reference numeral 1 denotes an intake pipe which serves as an intake passage, and the intake pipe 1 is connected to an intake side (not shown) of an engine body mounted on an automobile.

Reference numeral 2 denotes a throttle valve provided in the middle of the intake pipe 1, the throttle valve 2 constitutes an operating portion of an electronically controlled throttle valve, and the throttle valve 2 changes the flow area in the intake pipe 1. In order to do so, a butterfly type throttle valve body 3 fixed to a rotary shaft 14 described later, and a rotary electromagnetic actuator 11 for opening and closing the throttle valve body 3,
The throttle valve body 3 is generally composed of a throttle sensor 4 including a potentiometer or the like for detecting the valve opening degree of the throttle valve body 3 and outputting the detected opening degree to a control unit 5.

Reference numeral 5 denotes a control unit, which serves as a control unit for an electronically controlled throttle valve, and the control unit 5 is composed of a microcomputer. The throttle sensor 4 and the rotary electromagnetic actuator 11 are provided on the input side. Forward rotation coil 28, which will be described later,
The reverse rotation coil 29 and an opening sensor (not shown) provided on the accelerator pedal side are connected, and the output side is connected to the drive circuit 6 including a pair of transistors 6A and 6B.

Further, the control unit 5 has a built-in program for performing feedback control and the like, and this program includes an opening signal from the throttle sensor 4, a current value input to the forward rotation coil 28 and the reverse rotation coil 29. The control signal output to the transistors 6A and 6B of the drive circuit 6 is calculated based on the
The rotation of the rotary shaft 14 is adjusted by operating the. As a result, the opening degree of the throttle valve body 3 can be set in correspondence with the accelerator operation amount input from the opening sensor on the accelerator pedal side.

Further, 7 is a throttle lever, which is attached to the other end side of the rotary shaft 14 and springs 8 and 9 are arranged on the throttle lever 7 with one side locked. The spring 8 acts so that the throttle valve body 3 is in the valve closing position, and the spring 9 acts so that the throttle valve body 3 is in the valve opening position. As a result, the throttle valve body 3 is set to the neutral position by the springs 8 and 9, and the neutral position is a position slightly open from the fully closed position of the throttle valve 2.

Next, the rotary electromagnetic actuator used in this embodiment will be described with reference to FIGS.

In the figure, 11 is a rotary electromagnetic actuator according to this embodiment, and 12 is the rotary electromagnetic actuator 11.
Shows a cylindrical casing having the outer shape of
A rotary shaft support plate 13 having a shaft insertion hole 13A in the middle of 2
Are formed.

Reference numeral 14 is a rotary shaft for rotating the throttle valve body 3, and the rotary shaft 14 is the shaft insertion hole 1 of the rotary shaft support plate 13.
It is rotatably inserted in 3A, a disk-shaped magnet mounting plate 15 is fixed to one side of the rotary shaft 14, and the throttle valve body 3 is fixed to the other side. Further, one side of the rotary shaft 14 is inserted into the casing 12, and the other side thereof is projected from the casing 12 and extended into the intake pipe 1.

Reference numeral 16 denotes a magnet, and the magnet 1
As shown in FIG. 3, 6 includes a pair of fan-shaped magnets 16A and 16B fixed to a disk-shaped magnet mounting plate 15 fixed to one side of the rotary shaft 14. Of the fan-shaped magnets 16A and 16B, the surface of one fan-shaped magnet 16A has an N pole, and the other fan-shaped magnet 1
The surface of 6B serves as an S pole, and is mounted at the end surface on the magnet mounting plate 15. The opening angles of the fan-shaped magnets 16A and 16B are both θ1.

Reference numeral 17 denotes a core member having a substantially columnar shape as a whole, and the core member 17 faces the magnet 16 and is located on the axis of the rotary shaft 14 so as to be located on the casing 12.
It is provided by being inserted into one side. And the core member 1
7 is a tubular core 18, a rod-shaped core 23, and a plate-shaped core 26.
The tubular core 18, the rod-shaped core 23, and the plate-shaped core 26 are all made of electromagnetic stainless steel.

Reference numeral 18 denotes a tubular core which is the outer shape of the core member 17, and the tubular core 18 has a wall thickness gradually increasing from one side to the other side, as shown in FIGS. The tubular body 19 formed as described above, the opening 20 formed on one side of the tubular body 19, and a fan shape so as to face the magnet 16 at the other side of the tubular body 19. A fan-shaped lid portion 21 (see FIG. 5) formed, and an inclined opening portion 22 (see FIG. 4) formed by cutting a part of the tubular body 19 from the fan-shaped lid portion 21 toward the opening portion 20. It consists of

Here, the fan-shaped lid portion 21 has a fan-shaped magnet facing surface 21A, a taper surface 21B connecting the magnet facing surface 21A and the tubular body 19, and a fan-shaped magnet facing surface 21A. As described above, the slit 21C penetrates from the inner side in the radial direction toward the outer side.
The opening angle of the fan-shaped lid portion 21 is θ2.

Further, the thickness of the tubular body 19 is formed such that the thickness gradually increases from the opening 20 toward the fan-shaped lid 21, so that a virtual cross section from the side of the opening 20 shown in FIG. The area S1 and the area S2 of the virtual cross section from the fan-shaped lid portion 21 shown in FIG. 7 have a substantially constant cross-sectional area at any axial position.

Further, the fan-shaped lid portion 21 is formed with a slit 21C penetrating from the inner side to the outer side in the radial direction so as to divide the fan into two. The opening angle of the magnet facing surface 21A is .theta.2.

Reference numeral 23 denotes a rod-shaped core, and the rod-shaped core 23
As shown in FIGS. 5 and 10 to 12, the rod-shaped portion 24 is housed in the tubular core 18 and the forward rotation coil 28 and the reverse rotation coil 29 are wound around a coil bobbin 30. , The magnet 1 located on the other side of the rod-shaped portion 24 and combined with the fan-shaped lid portion 21 to form the same plane.
6 and a fan-shaped lid portion 25 (see FIG. 5) formed in a fan shape so as to face each other.

Here, the fan-shaped lid portion 25 has a fan-shaped magnet facing surface 25A, a taper surface 25B connecting the fan-shaped lid portion 25A and the rod-shaped portion 24, and the magnet facing surface 2
It is composed of a slit 25C penetrating from the radially outer side toward the inner side so as to divide the fan shape of 5A into two. The opening angle of the magnet facing surface 25A is θ3.

The outer peripheral surface of the rod-shaped portion 24 has a 90 ° angle.
Alternately, four slits 24A are formed in the axial direction.

Reference numeral 26 denotes a plate-shaped core, which has a conical shape with a low height, and has the rod-shaped core 23 at the center.
The shaft portion insertion hole 27 into which the rod-shaped portion 24 is inserted is formed. Further, the plate-shaped core 26 is inserted into the shaft insertion hole 27 at one end of the rod-shaped portion 24 of the rod-shaped core 23, and the outer periphery of the plate-shaped core 26 is inserted into the opening 20 of the tubular core 18. By fitting, the annular space between the opening 20 and the rod-shaped portion 24 is closed. Further, by forming the plate-shaped core 26 into a conical shape, the plate-shaped core 26
Since the height dimension is gradually reduced in the radial direction and the length dimension in the circumferential direction is sequentially increased, the surface area S3 of the virtual outer periphery having the small radial dimension shown in FIG. 13 and the radial dimension shown in FIG. The large virtual outer surface area S4 means that the surface area in the circumferential direction is constant at any radial position.

Reference numeral 28 is a forward rotation coil, and 29 is a reverse rotation coil. The forward rotation coil 28 and the reverse rotation coil 2 are respectively shown.
9 is wound around a rod-shaped portion 24 of the rod-shaped core 23 via a coil bobbin 30, and a normal rotation coil 28 is wound inside and a reverse rotation coil 29 is wound around the coil bobbin 30 outside. The forward rotation coil 28 operates as a closed coil in the electronically controlled throttle valve device described above, and the reverse rotation coil 29 operates as an open coil.

Further, the fan-shaped magnets 16A, 16B
Opening angle θ 1, the magnet facing surface 21 of the tubular core 18
The opening angle θ2 of A, the magnet facing surface 2 of the rod-shaped core 23
The relationship between the opening angle θ3 of 5A and the angle θ3
1 to θ 3 are applied devices, that is, in this embodiment, if the operating angle α and the built-in variation angle β of the throttle valve body 3 are set as shown in the following mathematical expression 1, an optimum magnetic field is generated to produce a valve. The opening can be adjusted accurately.

[0045]

[Formula 1] α + β ≦ 180 ° − {(θ3−θ1) +2 (1
80 ° -θ2)}

In this embodiment, α = 83 ° and β = 2
When 7 °, θ1 = 120 °, θ2 = θ3 = 17
It is set to 0 °.

Here, the operation of the rotary electromagnetic actuator 11 configured as described above will be described with reference to FIGS. 15 and 16.

First, when a current is input only to the forward rotation coil 28, the pole facing the magnet facing surface 25A of the rod-shaped core 23 of the core member 17 has the N pole, and the magnet facing surface 21A of the tubular core 18 has the S pole. Magnetized, magnet facing surface 25A
Generates a magnetic field from the magnet facing surface 21A.
On the other hand, the fan-shaped magnets 16A and 16B of the magnet 16
A magnetic field is always generated between the N-pole fan-shaped magnet 16A and the S-pole fan-shaped magnet 16B. Therefore, as shown in FIG. 15, the fan-shaped magnet 1 of the magnet 16 is used.
When 6A and 16B are neutral to the facing surfaces 21A and 25A of the core member 17, the magnetic fields generated from the facing surfaces 21A and 25A and the magnetic fields generated by the fan-shaped magnets 16A and 16B cause the magnet 16 to attract and repel. The rotating shaft 14 is rotated in the direction of the arrow (clockwise).

On the other hand, when a current is applied only to the reverse rotation coil 29, the S pole is opposed to the magnet facing surface 25A of the rod-shaped core 23 of the core member 17 and the magnet facing of the cylindrical core 18 is opposite to the above. An N pole is magnetized on the surface 21A, and a magnetic field is generated from the magnet facing surface 21A toward the magnet facing surface 25A. Therefore, as shown in FIG.
A, magnetic field generated from 25A and fan-shaped magnet 16A,
A magnetic field generated by 16B causes the magnet 16 to be attracted and repelled to rotate the rotary shaft 14 in the direction of the arrow (counterclockwise).

As described above, the rotary electromagnetic actuator 11 according to this embodiment has a predetermined frequency (for example, 300 Hz).
The signals having the opposite pulse waves are input to the forward rotation coil 28 and the reverse rotation coil 29, respectively. Therefore, when the signal input to the forward rotation coil 28 is ON, it is input to the reverse rotation coil 29. The signal that is input is OFF, and when the signal that is input to the forward rotation coil 28 is OFF, the signal that is input to the reverse rotation coil 29 is ON. As a result, when the pulse wave input to the forward rotation coil 28 is ON, the rotating shaft 14 is rotated clockwise by the magnetic field generated by the forward rotation coil 28, and when it is OFF, it is rotated by the magnetic field generated by the reverse rotation coil 29. Axis 14
Rotates counterclockwise. However, in reality, the rotation of the rotary shaft 14 cannot be performed by following ON / OFF of the pulse wave, and the rotary shaft 14 is held at the position corresponding to the duty ratio of the pulse wave. It will be.

That is, when the duty ratio of the pulse wave is 50%, the rotation of the rotary shaft 14 shown in FIG. 15 and the rotation of the rotary shaft 14 shown in FIG. 16 cancel each other out, and the rotary shaft 14 is neutral. It is held in the stopped position.

On the other hand, when the duty ratio of the pulse wave is input to the forward rotation coil 28 with the ON state lengthened, the rotation shaft 14 rotates in the clockwise direction as shown in FIG. It is held in place.

When the duty ratio of the pulse wave is input to the reverse rotation coil 29 with the ON state lengthened, the rotary shaft 14 rotates in the counterclockwise direction as shown in FIG. Held in place.

Next, the features of the components of the rotary electromagnetic actuator 11 that operates in this way will be described.

First, in the rotary electromagnetic actuator 11, since the core member 17 facing the magnet 16 is arranged on the axis of the rotary shaft 14, the core member is provided on the outer periphery of the magnet as in the rotary electromagnetic actuator of the prior art. It is no longer necessary to provide the rotary electromagnetic actuator 1
The radial dimension of 1 can be reduced, and the size can be reduced.

The magnet 16 is a pair of fan-shaped magnets 16A and 16B, and the fan-shaped magnets 16A and 16B
One of the fan-shaped magnets 6B whose surface is the N pole 1
The other fan-shaped magnet 16 whose surface becomes the S pole from 6A
A magnetic field is always generated toward B, and a magnetic field corresponding to the duty ratio of the pulse wave input to the positive rotation coil 28 and the reverse rotation coil 29 is generated between the magnet facing surfaces 21A and 25A of the core member 17. . Thereby, the rotating shaft 14
Are magnet facing surfaces 21A and 25 of the core member 17.
The magnetic field generated between A and the magnetic field generated between the fan-shaped magnets 16A and 16B can be attracted, repelled, and rotated.

At this time, the fan-shaped magnets 16A, 16
Since B and the fan-shaped lid portions 21 and 25 are fan-shaped,
The magnetic field generated from the magnet 16 is always attracted to the magnetic field generated from one of the fan-shaped lid portions 21 (25) or the magnetic field generated between the fan-shaped lid portions 21 and 25 (magnet facing surfaces 21A and 25A). Repulsion can be surely caused.

The core member 17 is the cylindrical core 1.
After forming one magnetic path from the three members of 8, the rod-shaped core 23 and the plate-shaped core 26, the forward rotation coil 28 and the reverse rotation coil 29 are wound around the rod-shaped portion 24 of the rod-shaped core 23. There is. As a result, when a current is input to the forward rotation coil 28 and the reverse rotation coil 29, the fan-shaped magnet facing surface 21A and the magnet facing surface 25A, which are both end portions of the core member 17 and are on the same plane in combination, are formed. Have different magnetic poles, and a magnetic field can be generated between the facing surfaces 21A and 25A.

Moreover, the cylindrical core 18 having different magnetic poles
Since the rod-shaped core 23 and the rod-shaped core 23 are reliably separated by the inclined opening 22 of the tubular core 18, magnetic interference between the tubular core 18 and the rod-shaped core 23 can be eliminated, and magnetic leakage can be reduced. .

The tubular core 18 has an inclined opening 22 formed in the tubular body 19, and the thickness of the tubular body 19 gradually increases from the opening 20 toward the fan-shaped lid 21. The rod-shaped core 23 has a rod-shaped portion 24 and a fan-shaped lid portion 25.
A taper surface 25B is formed between
Is formed in a conical shape that thickens from the outside toward the inside, so that the magnetic flux flowing in the core member 17 can always pass a constant magnetic path cross-sectional area (minimum magnetic path cross-sectional area). Magnetic leakage from the outside to the outside can be reduced.

Further, since the cylindrical core 18, the rod-shaped core 23, and the plate-shaped core 26 constituting the core member 17 are made of electromagnetic stainless steel, the eddy current generated in the core member 17 is reduced and the drive current is reduced. Therefore, the responsiveness of the rotary shaft 14 can be improved. Further, electromagnetic stainless steel can be cold forged, and the manufacturing cost can be reduced. In this embodiment, the core member 17 is made of electromagnetic stainless steel, but may be made of silicon steel or electromagnetic soft iron, and may be made of a material (for example, pure iron) having electric characteristics equivalent to those of silicon steel or electromagnetic soft iron. The powder may be used as a sintered alloy.

On the other hand, since the direction of the magnetic field flowing in the core member 17 is alternately generated by the forward rotation coil 28 and the reverse rotation coil 29, when the slit 24A is not formed in the rod-shaped portion 24, Eddy current I as shown in 17
0 is generated. However, as shown in FIG. 18, the outer peripheral surface of the rod-shaped portion 24 of the rod-shaped core 23 according to the present embodiment is 90 °.
Since the four slits 24A are formed every other position, it is possible to reduce the magnetic leakage by generating four eddy currents I1 for individually buffering the eddy currents generated on the outer periphery of the rod-shaped portion 24. Further, by suppressing the eddy current, it is possible to improve the response of the direction switching of the magnetic flux.

Further, as shown in the modified example of FIG. 19, the rod-shaped portion 2'can also be formed by forming eight slits 24A 'every 45 degrees on the outer peripheral surface of the rod-shaped portion 24' of the rod-shaped core 23 '.
The eddy currents generated on the outer circumference of 4'are generated as eight eddy currents I1 'which individually buffer, and magnetic leakage can be reduced to suppress the eddy currents.

Therefore, the core member 17 according to the present embodiment is
By forming the tubular core 18, the rod-shaped core 23, and the plate-shaped core 26 from three members, leakage of magnetic flux flowing through the core member 17 is reduced, and different magnetic fields are generated from the fan-shaped lid portion 21 and the fan-shaped lid portion 25. It can be generated efficiently. Thereby, the responsiveness of the rotating operation of the rotary shaft 14 by the rotary electromagnetic actuator 11 can be improved.

Further, as shown in FIG. 5, the fan-shaped lid portion 21 of the core member 17 has a slit 21C for dividing the fan into two.
Since the slit 25C for dividing the fan into two is formed in the fan-shaped lid portion 25, the fan-shaped lid portion 21 and the fan-shaped lid portion 2 are formed in the same manner as the slit 24A formed in the rod-shaped portion 24 described above.
It is possible to suppress the eddy currents by reducing the magnetic leakage by generating the eddy currents generated in 5 and 5 respectively as two eddy currents I2.

Thus, in this embodiment, the rotary electromagnetic actuator 11 configured as described above is used as the electronically controlled throttle valve, so that the rotary electromagnetic actuator 11 can be operated.
Since the core member 17 is arranged on the axis of the rotary shaft 14, the rotary electromagnetic actuator 11 can be downsized, and the layout of the electronically controlled throttle valve in the engine room can be reduced. It can be done easily.
Furthermore, the maintainability of the electronically controlled throttle valve can be improved.

In the above embodiment, the rotary electromagnetic actuator 11 is used as an electrically controlled throttle valve. However, the present invention is not limited to this and may be used as an idle speed control valve or the like. is there.

[0068]

As described above in detail, according to the present invention of claim 1, the duty ratio of the pulse wave input to each coil is controlled to generate from the fan-shaped lid portion of the tubular core of the core member. It is possible to adjust the strength of the magnetic field to be generated and the strength of the magnetic field generated from the fan-shaped lid portion of the rod-shaped core, and it is possible to rotate and hold the rotating shaft at a predetermined angle in relation to the magnetic field generated from the magnet.

According to the second aspect of the present invention, the magnet is formed as a pair of fan-shaped magnets, and the fan-shaped lid portions of the core member are also fan-shaped. Therefore, the rotary shaft provided with the fan-shaped magnets corresponds to each of the core members. It is rotated by the action of the magnetic field generated between the fan-shaped lids and the magnetic field generated between the fan-shaped magnets. At this time, the magnetic field generated from the magnets is always the magnetic field generated from one of the fan-shaped lids, or both of the fan-shaped magnetic fields. The magnetic field generated between the lids can be acted on, and the rotary shaft can be controlled to rotate by the magnetic fields at all times.

According to the third aspect of the present invention, a magnetic path having a constant cross-sectional area with respect to the magnetic flux flow of the core member is secured by the shape of the holder, the shape of the rod-shaped core, and the shape of the plate-shaped core that form the core member. Therefore, the magnetic flux leakage generated from the core member can be reduced to efficiently generate the magnetic field, and the rotational response of the rotary shaft can be improved.

According to the invention of claim 4, the tubular core, the rod-shaped core, and the plate-shaped core forming the core member are made of electromagnetic stainless steel, so that the eddy current generated in the core member can be reduced and the magnetic flux is generated in the core member. The response speed can be increased by reducing the drive current for generating. Further, it is possible to manufacture by cold forging, and it is possible to reduce the manufacturing cost.

According to the fifth aspect of the invention, since a plurality of slits are formed on the outer peripheral side of the core member, the eddy current generated on the outer peripheral side is reduced to a small eddy current to suppress the eddy current and to change the direction of the magnetic flux. Responsiveness can be improved and the rotating operation of the rotating shaft can be smoothly performed.

According to the sixth aspect of the present invention, the fan-shaped lid portion of the cylindrical core and the fan-shaped lid portion of the rod-shaped core are formed with slits that divide the fan at equal intervals, so that eddy currents generated on the surface of the fan-shaped lid portion are generated. As a small eddy current, energy due to the eddy current can be reduced to reduce leakage of magnetic flux.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing an electronically controlled throttle valve using a rotary electromagnetic actuator according to an embodiment of the present invention.

FIG. 2 is a vertical cross-sectional view showing the rotary electromagnetic actuator in FIG.

FIG. 3 is a front view showing the shape of a magnet.

FIG. 4 is an exploded perspective view showing a core member according to this embodiment.

FIG. 5 is a front view showing a pair of fan-shaped lid portions of the core member.

FIG. 6 is a vertical cross-sectional view of a tubular core.

FIG. 7 is a front view of a tubular core.

FIG. 8 is an explanatory view showing a virtual cross section of the tubular core at an arbitrary axial position.

FIG. 9 is an explanatory view showing a virtual cross section of the tubular core at an arbitrary axial position.

FIG. 10 is a side view of a rod-shaped core.

FIG. 11 is a front view of a rod-shaped core.

FIG. 12 is a rear view of the rod-shaped core.

FIG. 13 is an explanatory diagram showing a virtual outer periphery of a plate-shaped core at an arbitrary radial position.

FIG. 14 is an explanatory diagram showing a virtual outer periphery of a plate-shaped core at an arbitrary radial position.

FIG. 15 is an explanatory diagram showing clockwise rotation of a rotary shaft by a rotary electromagnetic actuator.

FIG. 16 is an explanatory diagram showing rotation of a rotary shaft in a counterclockwise direction by a rotary electromagnetic actuator.

FIG. 17 is an explanatory diagram showing an eddy current generated in a rod-shaped portion in which a slit is not formed on the outer peripheral surface.

FIG. 18 is an explanatory diagram showing an eddy current generated in a rod-shaped portion having a slit formed on the outer peripheral surface according to the present embodiment.

FIG. 19 is an explanatory diagram showing an eddy current generated in a rod-shaped portion having eight slits formed on the outer peripheral surface as a modified example of the present embodiment.

[Explanation of symbols]

 11 rotary electromagnetic actuator 12 casing 14 rotary shaft 16 magnets 16A, 16B fan-shaped magnet 17 core member 18 tubular core 19 tubular body 20 opening 21 fan-shaped lid 21A, 25A magnet facing surface 21B, 25B taper surface 21C, 24A, 25C slit 22 inclined opening 23 rod-shaped core 24 rod-shaped portion 25 fan-shaped lid 26 plate-shaped core 28 forward rotation coil 29 reverse rotation coil

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Keiichi Kai 1370 Onna, Atsugi-shi, Kanagawa Inside Unisex Jex Co., Ltd.

Claims (6)

[Claims] 1. A rotary shaft, a magnet provided on the rotary shaft, a core member provided so as to face the magnet, and a core member wound around the core member and provided between the magnet and the magnet. In a rotary electromagnetic actuator comprising a forward rotating coil and a reverse rotating coil that rotate the rotating shaft forward and backward by a magnetic field formed, the core member includes a fan-shaped lid portion having one side opening and the other side facing the magnet. A tubular core formed as a hollow tubular body, and a rod-shaped portion disposed in the tubular core, the one side being a rod around which the forward rotation coil and the reverse rotation coil are wound, and the other side being a fan-shaped lid of the tubular core. A rod-shaped core that is a fan-shaped lid portion that faces the magnet in combination with a portion, and is positioned between one end side of the rod-shaped portion of the rod-shaped core and the opening portion of the tubular core to cover the opening portion. Is arranged as And a plate-shaped core made of a disk-shaped body. 2. The magnet is formed into a disc shape by a pair of fan-shaped magnets having different magnetizing directions with respect to the core member, and the fan-shaped lid portion of the core member of the tubular core and the fan-shaped lid portion of the rod-shaped core. 2. The rotary electromagnetic actuator according to claim 1, wherein the rotary electromagnetic actuators are formed in fan-shaped bodies having different magnetization directions. 3. The tubular core has an inclined opening formed by cutting from the fan-shaped lid toward the opening, and the thickness of the tubular core gradually increases from the opening toward the fan-shaped lid. The rotary electromagnetic actuator according to claim 1, wherein the rotary electromagnetic actuator is formed as described above. 4. The rotary electromagnetic actuator according to claim 1, wherein the cylindrical core, the rod-shaped core, and the plate-shaped core forming the core member are made of electromagnetic stainless steel. 5. The rotary electromagnetic device according to claim 1, wherein a plurality of slits that divide the outer peripheral surface at equal intervals are formed in the outer peripheral surface of the rod-shaped portion of the rod-shaped core in the axial direction. Actuator. 6. The rotation according to claim 2, 3, 4 or 5, wherein slits that divide the fan-shaped lid portion of the cylindrical core and the fan-shaped lid portion of the rod-shaped core are equally formed in the radial direction. Type electromagnetic actuator.