JP2001003769A - Motor-driven throttle valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize a gap size through simple structure and to improve reliability by providing a rolling body to provide a gap between a stator and a rotor. SOLUTION: An electromagnetic actuator 9 consists of a stator 10 and a rotor 19. A plurality of ball bodies 27, 27,... to form an air gap with a specified size between an opposite surface part 13 on the stator side and an opposite surface part 23 on the rotor side are provided in a rolling manner between a stator core 11 and a rotor core 20. Further, the opposite surface parts 13 and 23 are constituted such that when rotation is carried out in a direction in which the areas of the surfaces opposite to each other are increased, the rotor 19 is rotated in the opening direction of a valve element 8. During energization to electromagnetic coils 17 and 18, a magnetic suction force generated between the opposite surface parts 13 and 23 forms a rotation drive force and the rotor 19 is rotated in an opening direction against the force of a return spring 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric throttle valve device which is suitably used for variably controlling an intake air amount of, for example, an automobile engine in accordance with an accelerator operation amount or the like.

[0002]

2. Description of the Related Art In general, for example, an electric throttle valve device for controlling an intake air amount of an engine or the like is provided with a throttle body having an intake passage formed therein, and the throttle body is rotatably provided with a bearing or the like. A valve shaft provided on the valve shaft, the valve body rotating with the valve shaft to open and close the intake passage, a stator provided on the throttle body, and the valve facing the stator. An electromagnetic actuator having a rotor provided on a shaft and driving a valve body through the valve shaft, and an urging member for urging the valve body toward a valve closing position or an intermediate opening position. (For example, Japanese Patent Application Laid-Open No. 9-287485).

Here, the stator of the electromagnetic actuator includes a core member provided on the throttle body, and an electromagnetic coil provided on the core member and generating a magnetic field when energized from the outside. It is constituted by a valve opening coil and a valve closing coil wound around a core member. Further, the rotor of the electromagnetic actuator includes a magnet or the like provided on the valve shaft facing the core member of the stator, and this magnet is attached to the protruding end side of the valve shaft via a disk-shaped member or the like. .

In this case, the electromagnetic actuator turns the valve shaft with a constant driving force by a magnetic force generated between the stator and the rotor. Therefore, an axial gap (air gap) having a predetermined dimension is formed between the stator and the rotor to generate a magnetic force of an appropriate magnitude therebetween.

For example, when a valve-opening coil is energized, the magnetic field generated in the core member of the stator attracts (or repels) the magnet of the rotor, so that the valve shaft provided with the rotor is biased. It rotates in the valve opening direction of the valve body against the spring. When the valve closing coil is energized, a magnetic field is generated in the core member in a direction opposite to that of the valve opening coil, so that the valve shaft rotates in the valve closing direction against the biasing spring.

Accordingly, the electric throttle valve device energizes, for example, a pulse current or the like having a variable duty ratio to the valve opening coil or the valve closing coil, and opens the valve shaft by an angle corresponding to the duty ratio. By turning, the intake passage of the throttle body is opened and closed by a valve body, and the intake air amount of the engine is variably controlled according to the accelerator operation amount and the like.

[0007]

By the way, in the above-mentioned electric throttle valve device of the prior art, the stator of the electromagnetic actuator is provided on the throttle body side, the rotor is provided on the valve shaft side, and the stator and the rotor are connected to each other. The valve body is opened and closed by rotating the valve shaft with a constant driving force using the magnetic force generated therebetween.

In this case, the driving force of the electromagnetic actuator tends to fluctuate according to the size of the air gap formed between the stator and the rotor. By positioning as accurately as possible with respect to the throttle body, the air gap is maintained at a predetermined size.

However, the valve shaft, which is a rotating component, is liable to be rattled due to mechanical structure, and the relative position between the stator and the rotor is determined by a large number of components such as a throttle body, a valve shaft, and bearings. The size of the air gap is often affected by not only rattling of the valve shaft but also dimensional errors and assembly errors of these parts.

[0010] For this reason, in the prior art, it is difficult to suppress the dimensional variation of the air gap, and the driving force of the electromagnetic actuator tends to be unstable due to the dimensional variation and the like. There is a problem that the valve closing operation or the like may be adversely affected, and the reliability is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and an object of the present invention is to form a gap having a certain dimension between a stator and a rotor of an electromagnetic actuator with high precision, and to provide a magnetic actuator with a small gap. An object of the present invention is to provide an electric throttle valve device capable of stabilizing driving force and operation of a valve element and improving reliability.

[0012]

In order to solve the above-mentioned problems, the present invention provides a throttle body having an intake passage formed therein, a valve shaft rotatably provided in the throttle body, and a valve. A valve body that is provided on the shaft and rotates together with the valve shaft to open and close the intake passage; a stator provided on the throttle body; and a rotor provided on the valve shaft facing the stator. And an electromagnetic actuator for driving a valve element via the valve shaft.

The first aspect of the present invention is characterized in that a plurality of gaps having a certain dimension are formed between the stator and the rotor of the electromagnetic actuator. The rolling element is provided so as to be able to roll.

According to this structure, a gap having a certain size can be formed between the stator and the rotor of the electromagnetic actuator by using a plurality of rolling elements. By rotating between them, the rotor can be smoothly rotated while maintaining the gap between them.

According to a second aspect of the present invention, the stator and the rotor are provided with annular grooves extending in the direction of rotation of the valve shaft at positions facing each other, and the rolling element is provided with the annular groove of the stator and the rotor. And a plurality of spheres which are rollably fitted to the annular groove and are arranged in the circumferential direction of the annular groove.

Thus, when the rotor rotates with respect to the stator, the plurality of spheres roll between the annular groove of the stator and the annular groove of the rotor, and can smoothly rotate the rotor. At this time, each sphere can hold a gap having a size corresponding to the outer diameter or the like between the stator and the rotor.

Further, according to the third aspect of the present invention, the stator includes a stator core provided on the throttle body, and an electromagnetic coil provided on the stator core and generating a magnetic field when energized from the outside,
The rotor is constituted by a rotor core provided on the valve shaft so as to face the stator core and being rotated by the stator core when the electromagnetic coil generates a magnetic field, by being attracted to the stator core.

Thus, when energizing the electromagnetic coil,
When a magnetic attraction force is generated between the stator core and the rotor core, the attraction force is applied to the rotor core as a rotational driving force. Then, the rotor core and the valve shaft can rotate in the valve opening direction of the valve body by the rotational driving force.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an electric throttle valve device according to an embodiment of the present invention will be described in detail with reference to FIGS.

Reference numeral 1 denotes a throttle body integrally formed by means such as aluminum die-casting. The throttle body 1 includes a throttle chamber 2 as an intake passage connected to an intake pipe (not shown) of the engine, and the like. The actuator case 3 is formed in a cylindrical shape with a stepped bottom having an opening at the tip end, and is provided with a sensor case 4 to which a throttle sensor 26 described later is attached. Have been.

Reference numeral 5 denotes a valve shaft rotatably provided on the throttle body 1 by using bearings 6, 7, and the like. The valve shaft 5 extends in the throttle chamber 2 in the radial direction, and has one end inside the actuator case 3. At the same time, the other end projects toward the sensor case 4 side. When the valve shaft 5 rotates in the direction indicated by the arrow A in FIG. 4, a valve body 8 described later opens, and when the valve shaft 5 rotates in the direction indicated by the arrow B, the valve body 8 closes.

Reference numeral 8 denotes a valve element provided on the valve shaft 5 in the throttle chamber 2. The valve element 8 is formed of a circular valve plate or the like corresponding to the inner diameter of the throttle chamber 2.
The throttle chamber 2 is opened and closed by turning integrally with the throttle valve 2, and the intake air amount of the engine is variably adjusted.

Reference numeral 9 denotes an electromagnetic actuator provided on the actuator case 5 of the throttle body 1. The electromagnetic actuator 9 includes a stator 10 and a rotor 1 described later.
9.

Reference numeral 10 denotes a stator fixed to the actuator case 5. The stator 10 includes stator cores 11 and 11, which will be described later, a stator-side sphere support portion 14, and electromagnetic coils 17 and 18.

11, 11 is, for example, silicon steel, permalloy,
Each of the stator cores 11 includes two stator cores formed using a soft magnetic material or the like having a low coercive force such as ferrite.
As shown in FIGS. 1 to 3, a semi-cylindrical coil mounting portion 12 whose base end side is fixed to a core connecting plate 16 described below,
Provided on the tip side of the coil mounting portion 12, for example, 40 to
A stator-side facing surface portion 13 formed in a substantially fan shape having a central angle of about 80 °, and a stator-side sphere support portion 14 described later.
And are integrally formed. The two stator cores 11 are arranged on the opposite sides of the valve shaft 5 in the radial direction with respect to the valve shaft 5, and are fixed in the actuator case 5 via the core connecting plate 16.

Numerals 14 and 14 denote a semi-circular stator-side sphere support for rotatably supporting a sphere 27 which will be described later. Each of the stator-side sphere supports 14 has a coil mounting member as shown in FIGS. It protrudes radially outward from the outer peripheral side of the portion 12, and is disposed at a position further away from the rotor core 20 in the axial direction than the stator-side facing surface portion 13.

A fitting groove 14 having a semicircular cross section for fitting a sphere 27 is provided on the surface side of each stator-side sphere supporting portion 14.
A is provided so as to face the rotor core 20. As shown in FIG. 5, the two stator-side sphere support portions 14 are connected at both ends in the circumferential direction via spacers 15 described later. Together with 15A, an annular groove extending in the rotation direction of the valve shaft 5 is formed.

Numerals 15 and 15 denote spacers formed of, for example, a non-magnetic material such as resin. As shown in FIG. 3 and FIG. The two sphere supports 14 are fixedly attached and are connected in a magnetically insulated state.
A fitting groove 15A is provided on the surface side of the spacer 15 so as to be continuous with the fitting groove 14A of each stator-side sphere support portion 14.

Reference numeral 16 denotes a substantially disk-shaped core connecting plate fixed to the opening side of the actuator case 3.
Is formed using a soft magnetic material such as silicon steel, permalloy, or ferrite as in the case of the stator core 11, and magnetically connects the two stator cores 11 and 11 and closes the inside of the actuator case 3. .

Reference numerals 17 and 18 denote electromagnetic coils wound around the outer peripheral sides of the coil mounting portions 12 and 12, respectively. The electromagnetic coils 17 and 18 are formed, for example, so that their winding directions are opposite to each other. 2 generates a magnetic field H in FIG.

Reference numeral 19 denotes a rotor which constitutes the electromagnetic actuator 9 together with the stator 10. The rotor 19 is constituted by a rotor core 20, which will be described later.

Reference numeral 20 denotes a substantially disk-shaped rotor core provided at one end of the valve shaft 5. As shown in FIGS. 2 and 4, the rotor core 20 is made of silicon steel, permalloy, ferrite, or the like, like the stator core 11. An annular mounting plate portion 22 made of a soft magnetic material or the like and fixed to the outer peripheral side of the valve shaft 5 using a lock nut 21 or the like in a detented state;
3 and 23 are integrally formed.

Reference numerals 23, 23 denote rotor-side facing surface portions provided on the mounting plate portion 22 corresponding to the respective stator cores 11, and the rotor-side facing surface portions 23 are located on opposite sides in the radial direction from each other. It protrudes in the axial direction from the part 22, and its tip side is
A part thereof faces the stator-side facing surface portion 13 of the stator core 11 with an axial gap therebetween.

In this case, as shown in FIG. 2, an air gap having a predetermined dimension in the axial direction of the valve shaft 5 is provided between the rotor-side facing surface portion 23 and the stator-side facing surface portion 13 by a sphere 27 described later, as shown in FIG. G is formed.

Here, the rotor-side facing surface portion 23 is formed in a substantially arc shape extending in the rotation direction over a central angle of, for example, about 90 to 130 °, and has a diameter in the valve closing direction of the valve body 8. The width in the direction is formed to increase gradually, and the wide portion 23B on the other end has a larger radial size than the narrow portion 23A on the one end.

As shown in FIG. 4, when the valve shaft 5 (valve element 8) is in the valve closing position, the narrow-width portion 23A side faces the stator-side facing surface portion 1 of the stator core 11.
Faced with 3. And the rotor side facing surface portion 23 is
When the wide portion 23B rotates in the direction of arrow A so as to face the stator-side facing surface portion 13, the facing area between the stator-side facing surface portion 13 and the rotor-side facing surface portion 23 gradually increases. Is configured to be equal to the valve opening direction of the valve body 8.

When a magnetic field H is formed by energizing the electromagnetic coils 17 and 18, the opposing surfaces 13 and 2 are located between the stator core 11 and the rotor core 20.
In the direction in which the opposing area between the three increases and the amount of magnetic flux passing between them increases, a rotational driving force consisting of a magnetic attractive force is generated. Is turned in the direction of the arrow A against the return spring 25 of FIG.

Numeral 24 denotes a rotor-side sphere support formed integrally with the rotor core 20. The rotor-side sphere support 24 is
As shown in FIG. 2, at a position facing the stator-side sphere support portion 14, the annular plate is formed as an annular plate protruding radially outward from the mounting plate portion 22 of the rotor core 20. It is arranged at a position separated in the axial direction. Further, the rotor-side sphere support portion 24 is provided with a fitting groove 24A having a semicircular arc cross section facing the fitting groove 14A on the stator core 11 side.

Reference numeral 25 denotes a throttle body 1 and a rotor core 2
0, and the return spring 25 is
As shown in FIG. 1, the valve shaft 5 is urged through the rotor core 20 in the valve closing direction of the valve body 8.

Numeral 26 denotes a throttle sensor attached to the sensor case 4 of the throttle body 1. The throttle sensor 26 comprises a potentiometer or the like as shown in FIG. Is detected.

Are spheres as rolling elements made of, for example, a non-magnetic metal material.
Has a predetermined outer diameter, and forms an air gap G having a predetermined axial dimension between the stator core 11 and the rotor core 20 corresponding to the outer diameter.

Each sphere 27 is rollably fitted into the fitting groove 14A of the stator-side sphere support portion 14 and the fitting groove 24A of the rotor-side sphere support portion 24, respectively.
Are arranged at a constant circumferential interval. In this case, the retainer 28 is formed of an annular plate or the like in which a plurality of loose fitting holes 28 </ b> A for loosely fitting the respective spheres 27 are formed, and keeps a constant interval between these spheres 27.

The electric throttle valve device according to the present embodiment has the above-described configuration, and its operation will now be described.

First, when the power supply to the electromagnetic coils 17 and 18 is stopped, the valve element 8 is held at a predetermined valve closing position by the spring force of the return spring 25. When a pulse current or the like is applied to the electromagnetic coils 17 and 18 from, for example, a control unit (not shown) for controlling the engine, a closed magnetic field formed by the stator core 11, the core connecting plate 16 and the rotor core 20 in FIG. Magnetic field H along the road
At this time, the magnetic flux passes through the gap between the stator-side facing surface portion 13 and the rotor-side facing surface portion 23 along the axial direction of the valve shaft 5.

In this case, the rotor core 20 is provided with a magnetic attraction force in a direction in which the facing area between the facing surface portions 13 and 23 increases and the amount of magnetic flux passing between them increases. A rotational driving force is applied. Then, the rotor core 20 rotates in the valve opening direction of the valve element 8 against the return spring 25 together with the valve shaft 5 by this rotational driving force, whereby the valve element 8 returns to the rotational driving force applied to the rotor core 20 with the return driving force. The valve is opened to an opening position where the spring force of the spring 25 is balanced.

Accordingly, the control unit changes the duty ratio of, for example, a pulse current to be supplied to the electromagnetic coils 17 and 18 to increase or decrease the magnitude of the rotational driving force applied to the rotor core 20, thereby changing the valve element 8. Open and close at the desired opening.

In this case, when the rotor 19 rotates with respect to the stator 10, each of the spheres 27 maintains an air gap G of a predetermined size between the stator-side facing surface portion 13 and the rotor-side facing surface portion 23. The ball 27 rolls along the fitting grooves 14A, 24A between the stator-side ball support 14 and the rotor-side ball support 24.

Thus, according to the present embodiment, a plurality of spheres 27 are rotatably provided between stator core 11 and rotor core 20, and these spheres 27 are used to form stator-side facing surface portion 13 and rotor-side facing surface portion 23. Since the air gap G having a predetermined size is formed between them, the size of the air gap G can be held with high accuracy with a simple structure using these spheres 27, and the dimensional variation can be reliably suppressed. it can.

Therefore, the driving force of the electromagnetic actuator 9 can be stabilized, the valve element 8 can be driven smoothly by the electromagnetic actuator 9, and the reliability as a throttle valve device can be improved.

Further, a fitting groove 14A is provided in the stator-side sphere support portion 14 of the stator core 11, and a fitting groove 24A is provided in the rotor-side sphere support portion 24 of the rotor core 20.
Since each sphere 27 is arranged so as to roll between these fitting grooves 14A and 24A, when the rotor 19 rotates with respect to the stator 10, each sphere 27 is fitted with the fitting grooves 14A and 24A.
By rolling between them, the rotor 19 can be smoothly rotated.

By simply forming each sphere 27 accurately, the size of the air gap G can be accurately maintained corresponding to the outer diameter of the sphere 27. For example, the actuator case 3, the valve shaft 5,
Variations in the dimensions of the air gap G due to dimensional errors of the bearings 6, 7 and the like, assembling errors, etc., and rattling of the valve shaft 5 can be reliably prevented.

The stator 1 of the electromagnetic actuator 9
0 is composed of the stator core 11 and the electromagnetic coils 17 and 18, and the rotor 19 is composed of the rotor core 20. Therefore, when the electromagnetic coils 17 and 18 are energized, the magnetic force generated between the stator core 11 and the rotor core 20. A rotational driving force in the valve opening direction of the valve body 8 can be generated by the suction force, and the rotor core 20 can rotate against the return spring 25 by the rotational driving force, and can rotate through the valve shaft 5 through the valve shaft 5. Can be opened. Accordingly, it is not necessary to use expensive magnets or mounting parts for magnets, and the number of parts of the electromagnetic actuator can be reduced to reduce costs.

In the above embodiment, a plurality of spheres 27 provided between the stator core 11 and the rotor core 20 are provided.
27 are held at a constant circumferential interval by the retainer 28, but the present invention is not limited to this. For example, FIG.
As shown in the modified example shown in FIG.
May be arranged along the fitting groove 24A and the like, and the retainer 28 may be omitted.

In the above embodiment, the ball 27 is used as the rolling element provided between the stator core 11 and the rotor core 20, but the present invention is not limited to this.
For example, a configuration using tapered rollers or the like instead of the spherical body 27 may be used.

[0055]

As described above in detail, according to the first aspect of the present invention, a plurality of rolling elements forming a gap having a certain size between a stator and a rotor of an electromagnetic actuator. Is provided so as to be able to roll, so that only by accurately forming the shape and dimensions of each rolling element, the gap dimensions can be formed with high precision by a simple structure using the rolling elements, such as a throttle body and a valve. Variations in the dimension of the gap due to dimensional errors of the shaft, bearings, etc., and rattling of the valve shaft can be reliably prevented. Therefore, the driving force of the electromagnetic actuator can be stabilized, the valve element can be smoothly driven by the electromagnetic actuator, and the reliability of the throttle valve device can be improved.

According to the second aspect of the present invention, the rolling element is constituted by a plurality of balls rollingly fitted between the annular groove of the stator and the annular groove of the rotor. When rotating with respect to the sphere, these spheres roll between the two annular grooves, so that the rotor can be smoothly rotated. At this time, the dimension of the gap is precisely adjusted according to the outer diameter of the sphere. Can hold well.

Further, according to the third aspect of the invention, the stator of the electromagnetic actuator is constituted by the stator core and the electromagnetic coil, and the rotor is constituted by the rotor core. The generated magnetic attraction force can generate a rotational driving force in the valve opening direction of the valve element, and the rotor core can be rotated by the rotational driving force and can open the valve element via the valve shaft. . Therefore, it is not necessary to use expensive magnets or mounting parts for magnets, so that the number of parts of the electromagnetic actuator can be reduced and cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an electric throttle valve device according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part showing the electromagnetic actuator in FIG. 1;

FIG. 3 is a cross-sectional view of a stator core and the like viewed from a direction indicated by arrows III-III in FIG.

FIG. 4 is a cross-sectional view of the rotor core and the like as viewed from a direction indicated by arrows IV-IV in FIG.

FIG. 5 is a perspective view showing a sphere arranged between a stator core and a rotor core.

FIG. 6 is a cross-sectional view of a rotor core and the like showing an electric throttle valve device according to a modification of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Throttle body 2 Throttle chamber (intake passage) 3 Actuator case (throttle body) 5 Valve shaft 8 Valve 9 Electromagnetic actuator 10 Stator 11 Stator core 14 Stator-side sphere support part (stator core) 14A Fitting groove (annular groove) 15 Spacer 15A Fitting groove (annular groove) 17, 18 Electromagnetic coil 19 Rotor 20 Rotor core 24 Rotor-side sphere support (rotor core) 24A Fitting groove (annular groove) 27 Sphere (rolling element)

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification FI FI Theme Court ゛ (Reference) H02K 33/02 H02K 33/02 B (72) Inventor Tomoaki Araki 1370 Onna, Atsugi-shi, Kanagawa Yu Inside Nissia Gex (72) Inventor Keiichi Kai 1370 Onna, Atsugi-shi, Kanagawa Prefecture F Units in Unisia Gex Co., Ltd. CC01 DD01 DD11 EE07 GG02 HH02 HH10 5H633 BB07 BB15 GG02 GG09 HH15 HH20 JA02 JA09 JB05

Claims (3)

[Claims] A throttle body having an intake passage formed therein; a valve shaft rotatably provided in the throttle body; and a valve shaft provided on the valve shaft and rotating together with the valve shaft to rotate the intake passage. An electromagnetic actuator having a valve body that opens and closes, a stator provided on the throttle body, and a rotor provided on the valve shaft facing the stator, and driving the valve body via the valve shaft. An electric throttle valve device comprising: a plurality of rolling elements that form a gap having a certain dimension between the stator and the rotor between the stator and the rotor of the electromagnetic actuator; An electrically operated throttle valve device, comprising: 2. The stator and the rotor are provided with annular grooves extending in the direction of rotation of the valve shaft at positions facing each other, and the rolling elements roll into the annular grooves of the stator and the rotor. 2. The electric throttle valve device according to claim 1, wherein the electric throttle valve device is constituted by a plurality of spheres which are fitted so as to be able to be arranged in the circumferential direction of the annular groove. 3. The stator comprises a stator core provided on the throttle body, and an electromagnetic coil provided on the stator core and generating a magnetic field when energized from the outside, wherein the rotor faces the stator core. 3. The electric motor according to claim 1, further comprising: a rotor core provided on the valve shaft and being attracted to the stator core when the electromagnetic coil generates a magnetic field, the rotor core rotating integrally with the valve shaft. 4. Type throttle valve device.