JP3188964B2 - Rotating magnetic field detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting a rotating magnetic field synchronized with the rotation of a rotating electric machine such as a motor.

[0002]

2. Description of the Related Art In general, this kind of rotating magnetic field detecting device is
For example, as shown in FIG.
The pole and the south pole are alternately magnetized by 8 poles, and the magnet ring 1 provided on the rotating side is opposed to the magnet ring 1 with a gap g therebetween on the fixed side with an electrical angle of 30 °. It comprises a magnetic pole sensor 2 (21, 22, 23) with three Hall elements attached, as shown in FIG.
The rotating magnetic field can be detected based on V2 and V3.

Here, as shown in FIG. 10, the phase difference between the outputs V1, V2 and V3 of the magnetic pole sensor 2 is 30 °, and the outputs V1, V2 and V3 are superposed by 15 °. The rotation magnetic field can be detected with the interval t. In the figure, T is a cycle of one rotation of the magnet ring 1.

In such a rotating magnetic field detecting device,
Misalignment of magnetized position of magnet ring 1, each magnetic pole sensor 2
Of the outputs V1, V2, and V2 of the magnetic pole sensor 2 due to factors such as variations in the characteristics of
The phase difference between V3 is shifted, and the detection accuracy of the rotating magnetic field is deteriorated.

[0005] In order to improve the processing accuracy of each part,
If magnetic pole sensors with uniform characteristics are selected, the yield of products will be poor and mass productivity will be poor.

For this reason, conventionally, the mounting position of each magnetic pole sensor can be individually shifted, and the detection timing of the rotating magnetic field is adjusted by changing the relative position between the magnetic pole sensors. The detection accuracy of the rotating magnetic field is increased (Japanese Patent Laid-Open No. 61-18340).
Gazette).

[0007]

The problem to be solved is that if the mounting position of each magnetic pole sensor is individually shifted after the assembly of the device to adjust the detection timing of the rotating magnetic field, it is difficult to adjust the timing. This makes the mechanism complicated, the adjustment work becomes complicated, and it is difficult to finely adjust the relative mounting position between the magnetic pole sensors.

[0008]

According to the present invention, there is provided a magnet ring provided on a rotating side in which N and S poles are alternately magnetized so as to be equally spaced on a circumference, and a gap is formed in the magnet ring. In a rotating magnetic field detecting device including a plurality of magnetic pole sensors provided on a fixed side with a predetermined electrical angle so as to be opposed to each other, fine adjustment of the detecting timing of the rotating magnetic field can be easily performed after assembling the device. To this end, an adjusting means for adjusting the relative electric angle between the magnetic pole sensors by deforming the substrate on which the magnetic pole sensors are attached is provided.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a rotating magnetic field detecting device according to the present invention is provided on a rotating side in which eight N poles and S poles are alternately magnetized so as to be equally spaced on a circumference. A magnetic pole sensor 2 (21, 21) comprising three micro-machined Hall elements provided on the fixed side with an electrical angle of 30 ° to each other so as to face the magnet ring 1 with a predetermined gap g therebetween with a predetermined gap g therebetween. 22 and 23), in particular, adjusting the relative electrical angle between the magnetic pole sensors 2 by mounting each magnetic pole sensor 2 on one substrate 3 and bending the substrate 3. Is provided.

As the adjusting means, as shown in FIGS. 2 and 3, when the substrate 3 is mounted on the fixed portion 4,
After the central portion of the substrate 3 is supported on the fixed portion 4 by the base 5, both ends of the substrate 3 in the circumferential direction are floated from the fixed portion 4 to the fixed side by screws 6. The substrate 3 is bent so that the end of the substrate 3 is appropriately bent by adjusting the tightening of the screw 6 so that the magnetic pole sensor 21 or 23 is attached to the end of the substrate 3. The electrical angle relative to the magnetic pole sensor 22 attached to the central portion can be adjusted.

That is, in FIG. 2, when the screw 6 is tightened to bend the end of the substrate 3, the position of the center of the magnetic pole sensing part of the magnetic pole sensor 21 or 23 attached to the end according to the amount of deflection. Moves by t in the rotation direction of the magnet ring 1 indicated by the arrow in the figure or in the opposite direction, whereby the magnetic pole sensor 21 or 23 attached to the end of the substrate 3 and the central part thereof are attached. The relative electric angle between the magnetic pole sensor 22 and the magnetic pole sensor 22 can be adjusted.

Each of the screws 6 is provided with a collar 7 for regulating the maximum deflection of the end of the substrate 3.

As a material of the substrate 3, a material having some flexibility is used. Then, as shown in FIGS. 1 and 2, the magnetic pole sensor 2 on the lower surface of the substrate 3 so that the substrate 3 is easily bent by tightening the screw 6.
Cut grooves 8 are formed at the boundary between the magnetic pole sensors 1 and 22 and the magnetic pole sensors 22 and 23, respectively.

In FIG. 4, the boundary between the magnetic pole sensors 21 and 22 and the boundary between the magnetic pole sensors 22 and 23 are formed on the lower surface of the substrate 3 so that the substrate 3 is easily bent by tightening the screws 6. A plurality of relatively large holes 9 are formed in a line shape.

The board 3 is also used as a circuit board for forming printed wiring of each magnetic pole sensor 2. Then, when the substrate 3 is bent, a jumper straddling a portion bent by the cut 8 (or a plurality of holes 9 shown in FIG. 4) in order to cope with peeling of the printed wiring at the bent portion. A predetermined wiring is provided using the line 10 (see FIG. 5).

FIG. 6 shows the characteristic of the variation of the electrical angle with respect to the rotation of the screw 6 when measured in an actual apparatus. The rotation of the screw 6 and the variation of the electrical angle when the substrate 3 is in a horizontal state are shown. It is at the reference point where both minutes are zero. Here, the setting is such that the maximum amount of deflection at the end of the substrate 3 is obtained when the screw 6 is tightened three turns from the reference point.

As shown in the characteristics of FIG. 6, when the screw 6 is turned to bend the end of the substrate 3, the contact portion between the head of the screw 6 and the substrate 3 is caught, and 6
There is a portion where the electrical angle does not fluctuate smoothly with respect to the rotation of.

In order to prevent such a situation from occurring,
As shown in FIG. 7, if the spherical collar 11 is provided between the head of the screw 6 and the substrate 3, the electrical angle can always be smoothly changed with respect to the rotation of the screw 6. become able to.

In the rotating magnetic field detecting device according to the present invention thus configured, the screws 6 at both ends of the substrate 3 are respectively turned to adjust the relative electrical angle between the magnetic pole sensors 2. As described above, as described above, the position of each magnetic pole sensor 2 caused by various factors such as a deviation of the magnetized position of the magnet ring 1, a variation in the characteristics of each magnetic pole sensor 2, a deviation of the mounting position of each magnetic pole sensor 2, etc. Output V
The rotation magnetic field can be detected with high accuracy by absorbing the phase difference between V1, V2, and V3.

As described above, according to the present invention, the screws for bending both ends of the substrate 3 on which the magnetic pole sensors 2 are fixedly mounted without individually moving the positions of the magnetic pole sensors 2. By simply turning 6, each magnetic pole sensor 2
The relative electrical angle between them can be easily and finely adjusted.

Further, according to the present invention, the relative electric angle between the magnetic pole sensors 2 can be adjusted without applying any mechanical stress to each magnetic pole sensor 2.

FIG. 8 shows another embodiment of the present invention.
In this case, the relative electrical angle between the magnetic pole sensors 2 can be adjusted by expanding and contracting the substrate 3 on which the magnetic pole sensors 2 are mounted.

That is, in this case, the boundary between the magnetic pole sensors 21 and 22 on the substrate 3 and the magnetic pole sensor 2
A slit 12 is cut at the boundary between the magnetic pole sensors 2 and 23. The slit 12 is appropriately widened by turning the screw 6 around each end of the substrate 3 fixed at the center, thereby expanding the slit 12 appropriately. The relative position can be adjusted.

Although not shown, the substrate 3 has a substrate structure in which both end portions can slide, so that the relative electrical angle between the magnetic pole sensors 2 can be adjusted by expanding and contracting the substrate 3. It is also possible.

[0025]

As described above, in the rotating magnetic field detecting device according to the present invention, the magnet ring provided on the rotating side, on which the N and S poles are alternately magnetized so as to be equally spaced on the circumference, In a rotating magnetic field detecting device comprising a plurality of magnetic pole sensors provided on a fixed side with a predetermined electrical angle so as to face the magnet ring via a gap,
By simple means, the detection timing of the rotating magnetic field can be easily and finely adjusted, and error factors such as deviation of the magnetized position of the magnet ring, variation of the characteristics of each magnetic pole sensor, and deviation of the mounting position of each magnetic pole sensor. And has the advantage that the rotating magnetic field can be detected with high accuracy.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a rotating magnetic field detection device according to the present invention.

FIG. 2 is a side view of a substrate portion on which the magnetic pole sensor according to the embodiment is mounted.

FIG. 3 is a side view of a substrate portion showing a state in which a screw is tightened to bend an end of the substrate in the embodiment.

FIG. 4 is a front view of the substrate showing a state in which wiring of each magnetic pole sensor is made.

FIG. 5 is a side view showing a jumper wire straddling a bent portion of the board when wiring of each magnetic pole sensor is performed.

FIG. 6 is a characteristic diagram showing an adjustment amount of an electrical angle with respect to rotation of a screw measured in the same embodiment.

FIG. 7 is a side view showing another example of the configuration of the screw portion for bending the end of the substrate.

FIG. 8 is a front view of a substrate portion according to another embodiment of the present invention.

FIG. 9 is a front view showing a general configuration of a rotating magnetic field detection device.

FIG. 10 is a time chart of an output signal of each magnetic pole sensor in the rotating magnetic field detection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnet ring 2 (21, 22, 23) Magnetic pole sensor 3 Substrate 6 Screw 8 Cut groove 9 Hole 12 Slit

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G01D 5/00-5/62 G01B ⁷ /00-7/34 G01B 11/00-11/30 G01P 1/00-3 / 80 H02K 11/00

Claims (3)

(57) [Claims] 1. A magnet ring provided on a rotating side in which N and S poles are alternately magnetized so as to be equally divided on a circumference, and a magnet ring opposed to the magnet ring via a gap. In a rotating magnetic field detection device including a plurality of magnetic pole sensors provided on a fixed side with a predetermined electrical angle, after mounting each magnetic pole sensor on one substrate,
An apparatus for detecting a rotating magnetic field, comprising adjusting means for adjusting the relative electrical angle between the magnetic pole sensors by deforming the substrate. 2. The rotating magnetic field detection according to claim 1, wherein the substrate on which the plurality of magnetic pole sensors are mounted is bent to adjust the relative electrical angle between the magnetic pole sensors. apparatus. 3. The rotating magnetic field according to claim 1, wherein a substrate on which a plurality of magnetic pole sensors are mounted is expanded and contracted to adjust a relative electrical angle between the magnetic pole sensors. Detection device.