JP2001145322A - Torque motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small torque motor capable of reducing man-hours for manufacturing by producing four or more stator poles with a single coil. SOLUTION: A rotor 41 consists of a rotor core disk 42 pressedly fixed to a throttle shaft, and rotor magnets 43, 44 fixed to the end surface of the rotor core 42 on a counter-throttle valve side with adhesives. The rotor magnets 43, 44 are disposed so as to form four-pole rotor poles whose polarities are different alternately in a rotational direction. A stator core 50 has the cores 51, 52 facing the rotor magnets 43, 44 at prescribed intervals in a rotation-axial direction, a shaft core 53 whose one axial end part connected to the facing core 51, a rear core 54 connected to the other axial end of the shaft core 53, and a side core 55 connected to the rear core 54 and the facing core 52. By the current through a coil 60, the four-pole stator poles are produced on the opposed cores 51, 52 with alternating different polarities.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a torque motor in which a rotor magnetic pole and a stator magnetic pole face each other with a predetermined space therebetween in the direction of a rotation axis, and more particularly to a torque motor used for a flow control valve or the like.

[0002]

2. Description of the Related Art Conventionally, a rotor magnetic pole and a stator magnetic pole are opposed to each other at a predetermined interval in the rotation axis direction.
A torque motor as disclosed in JP-A-504901 is known. Such a torque motor can be used as an actuator of a valve device such as an intake flow control valve of an internal combustion engine. In the configuration in which the rotor magnetic poles and the stator magnetic poles face each other with a predetermined interval in the rotation axis direction,
Even if the number of rotor magnetic poles and stator magnetic poles is four or more, the diameter of the torque motor does not increase. Further, the generated torque increases as the number of magnetic poles increases.

[0003]

However, the torque motor disclosed in Japanese Patent Laid-Open Publication No. Hei 6-504901 uses two coils when the stator magnetic pole is two poles and four coils when the stator magnetic pole is four poles. One coil is used for each stator pole. When a plurality of coils are used to generate a plurality of stator poles as described above, the number of windings of the coil increases and the size of the torque motor increases. Further, the number of steps for winding the coil increases. Furthermore, since electrical connection with terminals and the like is required for each coil, the number of electrical connection points increases and the number of manufacturing steps increases. SUMMARY OF THE INVENTION An object of the present invention is to provide a small-sized torque motor in which four or more stator magnetic poles are generated by one coil and the number of manufacturing steps is small.

[0004]

According to the torque motor of the present invention, the rotor magnetic pole having a plurality of magnets arranged in the rotational direction and the opposing core are spaced apart from each other by a predetermined distance in the rotational axis direction. Formed and opposed. Then, by energizing one coil, four or more stator magnetic poles having alternately different polarities in the rotation direction are generated in the opposed core.
Since four or more stator magnetic poles are generated by one coil, when the power used is the same, the number of windings of the coil is reduced as compared with a configuration in which four or more stator magnetic poles are generated using a plurality of coils. Therefore, the torque motor can be reduced in size and weight. Further, the number of steps for winding the coil is reduced. Further, the number of places where the coil is electrically connected to the terminals and the like is reduced, so that the number of manufacturing steps and the manufacturing cost are reduced. According to the torque motor according to the second aspect of the present invention, since the number of rotor magnetic poles and the number of stator magnetic poles are the same, the degree of opening can be adjusted with high accuracy within the rotation range defined by the number of magnetic poles.

[0005]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing an embodiment of the present invention. FIG. 4 shows a throttle device using a torque motor according to an embodiment of the present invention.
In FIG. 4, the throttle device 10 is in a fully closed state.
The throttle device 10 does not have a mechanism mechanically linked to an accelerator for adjusting the opening of the throttle valve 13 according to the accelerator pedal depression amount, and adjusts the opening of the throttle valve 13 only by the torque motor 40. .

The throttle body 1 of the throttle device 10
1 is a throttle shaft 1 through bearings 15 and 16
2 is rotatably supported. The throttle valve 13 is formed in a disk shape, and is fixed to the throttle shaft 12 with screws 14. When the throttle valve 13 rotates together with the throttle shaft 12, the flow passage area of the intake passage 11a formed by the inner wall of the throttle body 11 is adjusted, and the flow rate of intake air passing through the intake passage 11a is controlled.

A plate-shaped intermediate member 20 is inserted through one end of the throttle shaft 12 so as to be rotatable with the throttle shaft 12. The intermediate member 20 is urged by a return spring 21 in the valve closing direction of the throttle device 10. The intermediate member 20 is locked by a stopper (not shown) in the valve closing direction in the vicinity of the fully closed position slightly closer to the valve opening side than the fully closed position.
The plate-shaped locking member 22 is fixed to the throttle shaft 12 and rotates together with the throttle shaft 12. Locking member 22
The throttle shaft 12 is urged by an opener spring 24 in the valve opening direction of the throttle device 10.
The urging force of the return spring 21 is larger than the urging force of the opener spring 24. The locking lever 23 formed on the locking member 22 is locked by the stopper screw 25 at the fully closed position. The intermediate member 20 and the locking member 22 contact each other between the fully open position and the vicinity of the fully closed position, and separate from the intermediate member 20 and the locking member 22 between the vicinity of the fully closed position and the fully closed position.

The rotation angle sensor 30 is provided further on the end side of the throttle shaft 12 than the locking member 22, and is provided with a sensor rotor 31, a contact portion 32 attached to the sensor rotor 31, and a resistor. The substrate 33 is formed. The sensor rotor 31 is fixed to the throttle shaft 12 and rotates together with the throttle shaft 12.
A constant voltage of 5 V is applied to the resistor applied to the substrate 33, and when the sliding position between the resistor and the contact portion 32 changes according to the opening of the throttle valve 13, the output voltage value changes. An electronic control unit (ECU) (not shown) receives the output voltage value from the rotation angle sensor 30 and detects the opening of the throttle valve 13. At the other end of the throttle shaft 12, the rotor 41, the stator core 50 and the coil 6
A zero torque motor 40 is provided. The end of the torque motor 40 is covered by a cover 70.

As shown in FIG. 2 and FIG.
Are a disk-shaped rotor core 42 press-fitted and fixed to the throttle shaft 12, and rotor magnets 43, 4 attached to an end surface of the rotor core 42 on the side opposite to the throttle valve 13 with an adhesive or the like.
And 4. As shown in FIG. 1, the rotor magnets 43 and 44 are formed in a fan shape with a central angle of 90 °.
The rotor magnets 43 and 44 are arranged so as to form four rotor magnetic poles having different polarities alternately in the rotation direction.

As shown in FIGS. 2 and 3, the stator core 50 has opposed cores 51, 52 which face the rotor magnets 43, 44 at a predetermined interval d in the direction of the rotation axis, and one of the opposed cores 51, 52. Shaft core 53 to which axial ends are connected
And a rear core 54 connected to the other axial end of the shaft core 53, and a side core 55 connected to the rear core 54 and the opposing core 52. The shaft core 53 is not connected to the opposing core 52.

The opposing cores 51 and 52 are arranged alternately in the circumferential direction, and a coil 60 is wound around the shaft core 53. When current flows in the direction of arrow I in FIG. 1, magnetic flux flows in the direction of large arrows in FIG. Therefore, the opposing core 51 has an N pole, and the opposing core 52 has an S pole. When a current flows in the direction opposite to the arrow I in FIG. 1, magnetic flux flows in the direction opposite to the large arrow in FIG. Therefore, the opposing core 51 has an S pole and the opposing core 52 has an N pole. Regardless of the direction in which the current flows, stator poles having different polarities are alternately generated in the rotation direction by the opposed cores 51 and 52.

Next, the operation of the throttle device 10 will be described. Since the urging force of the return spring 21 is greater than the urging force of the opener spring 24, if the torque motor 40 does not generate torque, the throttle valve 13 is urged in the valve closing direction between the fully open position and the vicinity of the fully closed position. You. As shown in FIG. 2, the positions of the rotor magnetic pole and the stator magnetic pole are set so that the magnetic poles of the same polarity of the rotor magnetic pole and the stator magnetic pole face each other and the rotor magnetic pole slightly shifts in the valve opening direction near the fully closed position. Have been. When a current flows in the direction of arrow I shown in FIG.
1 and the throttle valve 13 rotate in the valve opening direction. The torque motor 40 generates a torque in the valve opening direction according to the amount of depression of the accelerator pedal, thereby adjusting the opening of the throttle valve 13 between the fully open position and the vicinity of the fully closed position.

The movement of the intermediate member 20 in the valve closing direction is locked by a stopper (not shown) near the fully closed position, and the locking member 22 rotates to the fully closed position. , The intermediate member 20 and the locking member 22 are separated. Between the vicinity of the fully closed position and the fully closed position, the urging force of the opener spring 24 acts on the locking member 22. Therefore, by flowing a current in the direction opposite to the arrow I direction shown in FIG. 1 between the vicinity of the fully closed position and the fully closed position, a torque is generated in the torque motor 40 in the valve closing direction. The opening of the throttle valve 13 is adjusted between the closed position and the closed position.

In the above-described embodiment showing the embodiment of the present invention, one coil 60 generates four stator magnetic poles. Therefore, compared to a case where four stator poles are generated by a plurality of coils, the number of windings of the coil is reduced if the same power is supplied. Therefore, the size of the torque motor can be reduced. Further, the number of steps for winding the coil is reduced. Also, the number of electrical connections between the coil and components such as terminals is reduced, so that the number of manufacturing steps and manufacturing costs are reduced.

In the above embodiment, four coils of the stator are generated by one coil. However, a torque motor that generates an even number of six or more magnetic poles by one coil may be configured. Further, the number of rotor magnetic poles and the number of stator magnetic poles may be different. In the above embodiment, the torque motor of the present invention is applied to the throttle device. However, it goes without saying that the torque motor of the present invention can be applied to a flow control valve for any use.

[Brief description of the drawings]

FIG. 1 is a schematic arrow view showing a rotor and a stator core according to an embodiment of the present invention.

FIG. 4 when the opening degree of the throttle valve is near the fully closed position.
FIG. 2 is a view as viewed in the direction of arrows II, with the cover removed.

FIG. 3 is a sectional view taken along line III-III in FIG. 2;

FIG. 4 is a sectional view showing a throttle device using the torque motor according to the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Throttle device 11 Throttle body 12 Throttle shaft 13 Throttle valve 40 Torque motor 41 Rotor 42 Rotor core 43, 44 Rotor magnet 50 Stator core 51, 52 Opposing core 53 Shaft core 54 Rear core 55 Side core 60 Coil

Continued on front page F-term (reference) 3G065 CA23 DA05 DA06 GA41 GA46 HA06 HA12 HA15 HA20 HA21 HA22 KA02 KA15 KA16 3H062 AA03 AA15 BB30 CC04 DD01 EE07 HH02 HH10 5H633 BB08 GG02 GG04 GG09 HH05 JA02

Claims (3)

[Claims] 1. A rotor in which a plurality of magnets are arranged in a rotational direction to form a plurality of rotor magnetic poles having different polarities alternately; one coil; and a predetermined gap formed with the magnet in a rotation axis direction. A stator core having four or more opposed cores arranged so as to face each other, and generating four or more stator magnetic poles having different polarities alternately in the rotation direction by energizing the coil in the opposed core. A torque motor, comprising: 2. The torque motor according to claim 1, wherein the number of the rotor magnetic poles is equal to the number of the stator magnetic poles. 3. The stator core according to claim 1, wherein:
An axial core around which the coil is wound, wherein one axial end is alternately connected to the four or more opposing cores and the other axial end is located away from the opposing rotor. A shaft core, a rear core connected to the other axial end of the shaft core, and an opposing core and the rear core that are not connected to one axial end of the shaft core, respectively. The torque motor according to claim 1, further comprising: a side core that is formed.