JPH08101222A - Magnetic rotation-sensor device - Google Patents

Abstract

PURPOSE: To provide a magnetic rotation-sensor device whose sensitivity is good in the small number of components and whose high working and assembly accuracy are not required. CONSTITUTION: A magnetic rotation-sensor device is provided with a magnet 24a, with a magnet 24b which is arranged in such a way that its magnetic-pole axis is crossed with the magnetic-pole axis of the magnet 24a at an angle of 90 deg., with a Hall IC 25 which detects the line of magnetic force of the magnet 24a and with a rotor 20 which detects a rotation state by means of the Hall IC 25. In the rotor 20, recessed parts 22 (nonmagnetic parts 223) by which respective lines of magnetic force of the magnets 24a, 24b are set to a repulsive state so as to reduce a line of magnetic force passing the Hall IC 25 and protruding parts 21 (magnetic parts) which collect the respective lines of magnetic force of the magnets 24a, 24b so as to increase the line of magnetic force passing the Hall IC 25 are made in parts in which the respective lines of magnetic force of the magnets 24a, 24b are overlapped. On the other hand, the magnetic- pole axis of one out of the magnet 24a and the magnet 24b is arranged nearly perpendicularly to the rotor 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic rotation sensor device, and more particularly to a magnetic rotation sensor device suitable as a wheel rotation sensor used in an anti-skid brake system of an automobile.

[0002]

11 and 12 show a conventional example of this type of magnetic rotation sensor device. FIG. 11 shows a first conventional example of a magnetic type rotation sensor device, in which 1 is a concave portion 1 a and a convex portion 1.
It is a rotor made of a magnetic material having b. Reference numeral 2 is a Hall IC, 3 is a magnet, and the Hall IC 2 and the magnet 3 are arranged along an axis parallel to the rotation axis 4. The Hall IC 2 is arranged below the rotor 1 and the magnet 3 is arranged above the rotor 1, and one of the S pole and the N pole (N pole in FIG. 11) of the magnet 3 faces the rotor 1. As shown in the figure, when the convex portion 1b is located between the Hall IC 2 and the magnet 3, the magnetic lines of force are concentrated in the convex portion 1b made of a magnetic material due to the magnetic shielding effect, so that the Hall IC 2 is located compared to the case where the concave portion 1a is located. The magnetic flux density at becomes smaller. in this way,
The magnitude of the magnetic flux density is detected by the Hall IC 2 to measure the rotation speed of the rotor 1.

In the magnetic rotation sensor device of FIG. 11, since the Hall IC 2 is of a type in which the magnitude change of the magnetic flux density formed by one magnet is detected, the leakage magnetic flux passing through a portion other than the Hall IC 2 becomes large, There was a problem that the magnetic flux density changes little and the sensitivity is low. As an example of a magnetic type rotation sensor device that improves this, Japanese Patent Laid-Open No. Hei 3 (1999)
No. -73863, and FIG. 12 is a diagram showing a schematic configuration thereof.

In the figure, rotors 5 and 6 made of a magnetic material are provided with concave portions 5a and 6a and convex portions 5b and 6b having the same shape, respectively, and the rotor 5 and the convex portion 6b face each other. And 6 are integrally attached to the shaft 7 at a predetermined distance from each other. A Hall IC 10 is provided between the rotor 5 and the rotor 6,
The magnet 8 is arranged above the rotor 6 and the magnet 9 is arranged below the rotor 6 so that the Hall IC 10 is sandwiched with the magnetic poles of the same kind facing each other.

When the shaft 7 rotates, the rotors 5 and 6 rotate together, and when the convex portion 5b is located between the magnet 8 and the Hall IC 10, the concave portion 6a is located between the magnet 9 and the Hall IC 10. . In this arrangement, the magnetic flux density of the magnet 8 in the Hall IC 10 is reduced by the magnetic shielding effect of the convex portion 5b, and an upward magnetic flux density is formed at the position of the Hall IC 10. On the other hand, when the concave portion 5a is located between the magnet 8 and the Hall IC 10 and the convex portion 6b is located between the magnet 9 and the Hall IC 10, a downward magnetic flux density is formed at the position of the Hall IC 10. As described above, the magnetic rotation sensor device shown in FIG. 12 can measure the rotation speed by detecting the magnetic flux density in which the direction is reversed. Therefore, the Hall IC 10 due to temperature changes, etc.
It is possible to reduce the influence of the output fluctuation of the magnets 8 and 9.

[0006]

However, in the magnetic rotation sensor device shown in FIG. 12, one rotor must be added to the magnetic rotation sensor device shown in FIG. 11 in order to form a magnetic flux whose direction is reversed. However, the number of parts increases.
Further, since the magnets 8 and 9 and the Hall IC 10 need to be arranged in the direction of the rotating shaft 7 while maintaining a slight gap, it is necessary to increase the accuracy of assembly of the rotors 5 and 6 in the rotating shaft direction. However, when the magnetic rotation sensor device of FIG. 12 is used for an anti-skid brake system of an automobile, the rotor is press-fitted in the rotation axis direction and mounted on the shaft, so that the machining and assembling accuracy in the radial direction of the rotor are Although it is relatively easy to secure, the actual situation is that the processing and assembling accuracy of the rotor in the direction of the rotation axis usually allow an error of about 3 mm. Therefore, it is difficult to secure the assembling accuracy in the rotation axis direction of the rotor, and unless the magnetic rotation sensor device of FIG. 12 is provided with an adjusting mechanism that is movable in the rotation axis direction of the rotor, the magnetic rotation of FIG. It is difficult to apply the sensor device, which causes a cost increase. Further, the rotor of FIG. 12 needs to be thin and have a deep recess in order to improve sensitivity, but when used in an anti-brake system of an automobile, foreign matter such as stones or grass may be caught or caught, It is expected that the detection performance will be degraded and damage will occur.

It is an object of the present invention to provide a magnetic rotation sensor device which improves performance at low cost, has a small number of parts, is highly sensitive, and does not require high processing and assembly precision.

[0008]

To explain with reference to FIG. 1 showing an embodiment, a magnetic rotation sensor device according to the invention of claim 1 has a first magnet 24a and a magnet 24 having a first magnetic pole axis.
The second magnet 24b arranged so as to intersect the magnetic pole axis of a at a predetermined angle, the magnetoelectric conversion element 25 for detecting the magnetic lines of force of the first magnet 24a, and the rotation state is detected by the magnetoelectric conversion element 25. Rotor 20 and the rotor 2
0 is the first magnet 2 so that the lines of magnetic force passing through the magnetoelectric conversion element 25 decrease at the portions where the lines of magnetic force of the first magnet 24a and the lines of magnetic force of the second magnet 24b overlap.
4a and the second magnet 24b, the non-magnetic portion 223 that repels the magnetic lines of force, and the first magnet 24a and the second magnet 24b so that the lines of magnetic force passing through the magnetoelectric conversion element 25 increase. Magnetic part 21 for collecting magnetic lines of force
While providing the first magnet 24a and the second magnet 2
One of the magnetic pole axes 4b is arranged substantially perpendicular to the rotor 20 to achieve the above object. Like Claim 2, 1st magnet 24a and 2nd magnet 24b may be arrange | positioned so that the angle which these magnetic pole axes make may be about 90 degrees. Referring to FIG. 8, the magnetic rotation sensor device according to a third aspect of the present invention includes a plurality of annular base portions 61 and a plurality of annular base portions that are provided in a circumferential direction of the base portion 61 so as to project in the rotational axis direction and have a predetermined pitch. A rotor having a magnetic portion 62 of
A pair of magnets 24a and 24b arranged so that the same magnetic poles face each other across the magnetic portion 62, and a pair of magnets 2
The above-described object is achieved by including the magnetoelectric conversion element 25 provided between one of the magnets 4a and 24b and the magnetic portion 62.

[0009]

According to the magnetic type rotation sensor device of the present invention,
The non-magnetic portion 223 repels the magnetic lines of force of the first magnet 24a and the second magnet 24b arranged so that their magnetic pole axes intersect at a predetermined angle, and the magnetoelectric conversion element 25.
Reduce the magnetic field lines passing through. The magnetic part 21 collects the magnetic force lines of the first magnet 24 a and the second magnet 24 b to increase the magnetic force lines passing through the magnetoelectric conversion element 25. The magnetoelectric conversion element 25 detects the magnetic line of force of the first magnet 24 a passing through the magnetoelectric conversion element 25. In the magnetic type rotation sensor device of the third aspect of the invention, the magnetic portions 62 projecting in the peripheral direction of the annular base portion 61 in the rotation axis direction and formed in an annular shape at a predetermined pitch are the same with the magnetic portion 62 interposed therebetween. A pair of magnets 24a and 24b arranged so that their magnetic poles face each other.
The magnetic lines of force are collected and the lines of magnetic force passing through the magnetoelectric conversion element 25 are increased. The magnetic-electric conversion element 25 is a magnetic-electric conversion element 25.
The magnetic lines of force of the first magnet 24a passing through are detected.

Incidentally, in the section of means and action for solving the above problems for explaining the constitution of the present invention, the drawings of the embodiments are used for the purpose of making the present invention easy to understand. It is not limited to.

[0011]

Embodiments of the present invention will be described below with reference to FIGS. -First Embodiment- Fig. 1 is a sectional view showing a first embodiment of the magnetic rotation sensor device according to the present invention, and shows the positional relationship between the rotor and the magnetic rotation sensor device. Reference numeral 20 denotes a rotor made of a magnetic material, which is attached to a shaft (not shown) by the fitting portion 20a. As shown in FIG. 3 (b), a plurality of convex portions 21 and concave portions 22 are alternately provided on the outer peripheral portion of the rotor 20 in the rotation direction. The concave portions 22 have a groove 221 parallel to the axis and an axial direction. And a groove 222 forming an angle of 45 degrees.
Reference numeral 223 is a space formed by the concave portion 22, and has a function as a non-magnetic portion having a magnetic permeability smaller than that of the convex portion 21 made of a magnetic material. Reference numeral 23 is a magnetic type rotation sensor, in which a first magnet 24a and a second magnet 24b made of a material such as rare earth cobalt, neodymium iron and alnico and a Hall IC 25 which is a magnetoelectric conversion element are provided on a substrate 28. There is. The magnet 24a provided so that its magnetic pole axis is orthogonal to the axis of the rotor 20 is arranged so that its magnetic pole axis faces the groove 222, while the magnet 24b has its magnetic pole axis in the thickness direction of the rotor 20. Is located in. Therefore, the magnet 2
The magnetic lines of force 4a and 24b are orthogonal to each other in the uneven portion of the rotor 20. The Hall IC 25 is arranged between the magnet 24a and the rotor 20 so as to face the N pole of the magnet 24a.

As shown in FIG. 2A, the magnet 24a and the Hall IC 25 are arranged in close contact with each other so that the magnetic pole axis of the magnet 24a and the magnetic flux detection axis of the Hall IC 25 overlap with each other, and cover the magnet 24a and the Hall IC 25. As described above, the magnet fixing member 26a is integrally formed of resin. 27 a is a mounting portion formed on the magnet fixing member 26 a.
The magnet fixing member 26a is attached to the substrate 28 shown in FIG. 1 by welding using a. In FIG. 2B, the magnet fixing member 26b is the same as the magnet fixing member 26a.
The magnet fixing member 2 is integrally molded with resin so as to cover 4b.
A mounting portion 27b is formed on 6b.

FIG. 3A is an enlarged view of the magnetic rotation sensor 23 shown in FIG. 1 and its surroundings. 29a and 29b
Is a resistor, and 30a and 30b are capacitors, which are attached to the substrate 28, respectively. The board 28 is attached to the connector 32 provided on the case pedestal 31, and then covered with a non-magnetic stainless steel case 33 to be sealed. At this time, the inside of the case 33 is filled with the molding material. The outer peripheral portion of the case 33 and the case pedestal 31
An O-ring 34 is mounted between and in order to ensure airtightness. FIG. 3B is a DD cross-sectional view shown in FIG. 3A, in which the magnet fixing member 26 a is attached to the mounting portion 27 as described above.
It is attached to the substrate 28 by a. When the rotor 20 rotates in the direction of the arrow in the figure, the magnet 24a and the Hall IC 25 housed in the magnet fixing member 26a alternately face the non-magnetic portion 223 which is the space of the convex portion 21 and the concave portion 22. Similarly, the magnet 24b shown in FIG.
And the non-magnetic portion 223 alternately face each other.

The change in the magnetic flux density in the Hall IC 25 with the rotation of the rotor 20 will be described with reference to FIGS. 4 and 5. In FIG. 4, the non-magnetic portion 223 of the rotor 20 is replaced by the magnet 24.
a and the case where it faces Hall IC 25. FIG.
FIG. 4A shows the state of the magnetic force lines when there is only one magnet, that is, only the magnets 24a as in the conventional magnetic rotation sensor device, and FIG. 4B shows the magnetic force lines of the magnetic rotation sensor device of the present invention. The respective states are schematically represented in proportion to the magnetic flux density. In FIG. 4A, 241-2
45 is a magnetic force line from the north pole to the south pole of the magnet 24a,
Hall IC with three lines of magnetic force 241, 243 and 244
It has passed 25. On the other hand, in FIG.
Since b and the magnet 24a are provided so that the N poles face each other at an angle of 90 degrees, the magnetic force lines 24 of the magnet 24a
1 to 245 and the magnetic lines of force 246 and 247 of the magnet 24b overlap each other, they repel each other. Therefore, the magnetic force lines 241 to 247 are as shown in the figure, and the Hall I
There are no lines of magnetic force passing through C25.

Next, the protrusion 21 of the rotor 20 is replaced by the magnet 24.
FIG. 5 shows the case where they face a and the Hall IC 25.
In FIG. 5 (a) showing the conventional magnetic rotation sensor device, since the convex portion 21 made of a magnetic material is located so as to face the N pole of the magnet 24a, the magnetic pole of the convex portion 21 is removed from the N pole. The generated magnetic force lines are attracted to the convex portion 21 having a high magnetic permeability, and the five magnetic force lines 241 to 245 pass through the Hall IC 25. On the other hand, in FIG. 5B showing the magnetic rotation sensor device of the present invention, the N pole of the magnet 24b comes to face the convex portion 21, and the magnetic force lines 246 and 247 of the magnet 24b.
Are attracted to the convex portion 21 due to the magnetism collecting action. Therefore, the magnetic force lines 246 and 247 and the magnetic force line 2 of the magnet 24a are
The repulsive action acting between 41 and 245 is weakened. Further, the magnetic force lines 241 to 245 are subjected to the magnetism collecting action by the convex portion 21 as in the case of FIG. Therefore, the five magnetic force lines 241 to 245 come to pass through the Hall IC 25.

FIG. 6 is a diagram showing changes in the output voltage of the Hall IC 25. The horizontal axis represents the rotation angle of the rotor, and the vertical axis represents the output voltage of the Hall IC at each rotation angle. It should be noted that x is a rotation angle when the concave portion 22 faces the Hall IC 25, and y indicates a rotation angle when the convex portion 21 faces the Hall IC 25. FIG. 6A shows the output voltage of the conventional magnetic rotation sensor device shown in FIGS. 4A and 5A, and the number of magnetic force lines passing through the Hall IC 25 at the rotation angle x (three). And Hall IC25 at rotation angle y
The magnitude of the output voltage is shown in correspondence with the number (5) of magnetic force lines passing through. On the other hand, FIG. 6B shows the output voltage of the magnetic type rotation sensor device of the present invention. In the case of the rotation angle x, the output voltage is 0 and the rotation angle y of the magnetic field line passing through the Hall IC 25 is 0. In the case, as in the conventional case, the magnetic force lines passing through the Hall IC 25 are five, and therefore the output voltage is the same as in the case of FIG. 6A. As described above, in the magnetic rotation sensor device of the present invention, the Hall IC 2
The magnitude change of the output voltage of No. 5 can be increased.

FIG. 7 is a diagram showing a circuit configuration and a two-wire type signal transmission system of the magnetic rotation sensor device of the present invention. The area indicated by A is the Hall IC 25, the area indicated by B is the sensor section, and FIG.
The area indicated by C is the area indicating the control unit. The control unit C supplies a voltage of +5 (V) to the Vcc terminal 43 of the Hall IC 25 via the ECU terminal 40a, the cable core wire 41a and the signal terminal 42a, and the constant current source 44 supplies a constant current to the Hall element 45.
Is supplied to. The outputs from the two terminals 46a and 46b of the Hall element 45 are supplied to a differential amplifier 47, and after the two differences are voltage-amplified by the differential amplifier 47 to a predetermined amplification factor, they are provided on the substrate 28 via a terminal 48. The direct current component is cut off by the connected capacitor 30b.
After that, it is guided to the Hall IC 25 again and input to the hysteresis comparator 50.

After that, the hysteresis comparator 50
Outputs a high level signal (+5 (V)) when the input voltage is higher than 0 (V), and outputs a low level signal (0 (V)) when the input voltage is lower than 0 (V). This signal is input to the base of the switching element 51 composed of a transistor. Switching element 51 has a collector connected to Vcc terminal 43 and an emitter connected to output terminal 52, and switching element 51 is turned on / off according to the base voltage. Resistor 29b is Hall IC
25 between the output terminal 52 of 25 and the GND terminal 53.
9a is the Vcc terminal 43 and the GND terminal 5 of the Hall IC 25
The capacitors 30a connected to the Vcc terminal 43 and the capacitor 30a for reducing the surge voltage fluctuation of the Vcc terminal 43 are provided between the Vcc terminal 43 and the GND terminal 53, respectively.

As the switching element 51 is turned on / off, the current flowing between the signal terminals 42a and 42b changes according to the voltage division ratio of the resistors 29a and 29b. Therefore, the voltage can be supplied while confirming the state of the switching element 51, and a two-wire configuration with the cable core wires 41a and 41b can be provided between the control unit C and the sensor unit B. A change in current flowing into the control unit C through the ECU terminal 40b is converted into a change in voltage by the resistor 54 and detected by the voltage detector 55.

In this embodiment, the first magnet is arranged in the direction in which its magnetic pole axis is orthogonal to the axis of the rotor, and the second magnet is arranged in its magnetic pole axis in the axial direction of the rotor, and the first magnet is arranged. Since the Hall IC for detecting the magnetic force line of the magnet is arranged between the first magnet and the rotor periphery, the gap between the Hall IC and the rotor can be made small and the assembling can be performed with high accuracy. Can be greatly changed, and a magnetic rotation sensor device with high sensitivity can be realized. Further, since the groove 222 can be molded by the conventional rotor processing method, new processing equipment is not required and the rotor processing cost is low.

In the present embodiment, the magnetoelectric conversion element is not limited to the Hall IC, but a magnetoresistive element or the like may be used. Further, although the first magnet 24a and the Hall IC 25 are arranged so as to be orthogonal to the axis of the rotor 20 as described above, that is, at an angle of 90 degrees, the intersecting angle of the magnetic pole axes of the magnet 24a and the magnet 24b is 90 degrees. Not limited to Further, the S poles may be opposed to each other. Further, although the rotor 20 is made of a magnetic material, only the convex portion 21 may be made of a magnetic material, and a substance having a sufficiently small magnetic permeability, such as a synthetic resin, is provided in the space corresponding to the concave portion 22. A rotor that is filled and has no recess may be used. The arrangement of the first magnet 24a and the Hall IC 25 and the arrangement of the second magnet may be exchanged. Further, the groove 222 may be omitted.

-Second Embodiment- FIG. 8 is a sectional view showing a second embodiment of the magnetic rotation sensor device according to the present invention, showing the positional relationship between the rotor 60 made of a magnetic material and the magnetic rotation sensor 23. It represents. In FIG. 8, the same parts as those in FIGS. 1 and 3 are designated by the same reference numerals, and different points are mainly described. The base portion 61 of the rotor 60 attached to the shaft (not shown) by the fitting portion 60a is formed in an annular shape, and a plurality of convex portions 62 and concave portions 63 extending in the axial direction of the rotor 60 rotate around the peripheral portion thereof. It is provided alternately in the direction. Reference numeral 631 is a space formed by the concave portion 63 and forms a non-magnetic portion having a magnetic permeability smaller than that of the convex portion 62 made of a magnetic material. The magnets 24a and 24b of the magnetic rotation sensor 23 are provided on the substrate 28 so that the N poles face each other with the convex portion 62 and the concave portion 63 sandwiched therebetween, and the Hall IC 25, which is a magnetoelectric conversion element, contacts the magnet 24a.
And the convex portion 62 and the concave portion 63.

FIG. 9 is an enlarged view of the magnetic rotation sensor 23 of FIG. 8, showing a case where the convex portion 62 is located between the magnets 24a and 24b. The other configuration of the magnetic rotation sensor 23 is the same as that of the magnetic rotation sensor device described in the first embodiment, and the description thereof is omitted. FIG. 9B shows FIG.
It is an EE sectional view shown in (a), and is magnets 24a and 24.
The magnet fixing members 26a and 26b accommodating b are attached to the substrate 28 by the attaching portions 27a and 27b. When the rotor 60 shown in FIG. 8 rotates in the direction of the arrow in FIG. 9B, the convex portions 62 and the concave portions 63 (nonmagnetic portion 631) alternately pass between the magnet 24a and the Hall IC 25.

FIG. 10 shows the hall I as the rotor 60 rotates.
It is a figure explaining the change of the magnetic flux density in C25, and Drawing 10 (a) shows nonmagnetic part 63 between magnets 24a and 24b.
1 is located, and FIG. 10B shows a case where the convex portion 62 is located. In FIG. 10A, the magnet 24a
And 24b have the same magnetic poles, the magnet 2
The magnetic lines 241-245 of 4a are the magnetic lines 24 of the magnet 24b.
The number of magnetic lines of force repulsing 6 and 247 and passing through the Hall IC 25 is zero. On the other hand, in FIG. 10B, the magnetic force lines 241 are generated due to the magnetic flux collecting action of the convex portion 62 made of a magnetic material.
˜247 are attracted to the convex portion 62. As a result, the magnetic force lines 241 to 245 come to pass through the Hall IC 25, and the number of magnetic force lines passing through the Hall IC 25 becomes five. Therefore, the output voltage of the Hall IC 25 is as shown in FIG.
It shows the same changes as in (b).

In this embodiment, the first and second magnets and the Hall IC are arranged orthogonally to the axis of the rotor, so that the gap between the Hall IC and the rotor can be made small and the assembly can be performed accurately. Since a mechanism for adjusting the magnetic rotation sensor in the axial direction of the rotor is unnecessary, the cost is low. Furthermore, since the first magnet and the second magnet are arranged on the same axis so that the same magnetic poles face each other, it is possible to increase the magnitude of the magnetic flux density in the Hall IC, and to provide a magnetic rotation sensor device with high sensitivity. It will be possible. In addition, since the convex and concave portions of the rotor are formed by bending not in the radial direction but in the rotational axis direction, foreign matter such as stones and grass are hardly caught or caught, and there is little risk of performance deterioration or damage. In addition, since the rotor has a U-shaped cross-section, it has a higher strength than a flat plate even with the same plate thickness and is less likely to be damaged.

In the present embodiment, the magnetoelectric conversion element is not limited to the Hall IC, but a magnetoresistive element or the like may be used. Further, the first magnet 24a and the second magnet 24b may be arranged with their S poles facing each other. Further, although the rotor 60 is formed of a magnetic material, only the convex portion 62 may be formed of a magnetic material, and a substance having a sufficiently small magnetic permeability, such as a synthetic resin, may be formed in the space corresponding to the concave portion 63. A rotor that is filled and has no recess may be used.

In the correspondence between the embodiment described above and the claims, the convex portions 21 and 62 form a magnetic portion.

As described above, according to the magnetic type rotation sensor device of the present invention, at the position of the magnetoelectric conversion element,
A pair of magnets are arranged so that the magnetic lines of force of the respective magnets repel each other, and when the non-magnetic portion provided on the rotor faces the magnetoelectric conversion element, there are few magnetic lines of force that pass through the magnetoelectric conversion element and the magnetic field lines are provided on the rotor. When the magnetic portion faces the magnetoelectric conversion element, the magnetic portion collects the magnetic force lines to increase the number of magnetic force lines passing through the magnetoelectric conversion element. The magnitude change can be increased, and a magnetic rotation sensor device with high sensitivity can be obtained without increasing the number of rotors. According to another aspect of the magnetic rotation sensor device of the present invention, the first magnet is arranged such that its magnetic pole axis is orthogonal to the axis of the rotor,
The magnet of which the magnetic pole axis is arranged in the axial direction of the rotor, and
Since the magnetoelectric conversion element that detects the magnetic force line of the first magnet is arranged between the first magnet and the rotor periphery, the gap between the magnetoelectric conversion element and the rotor can be made small and it is possible to assemble with high accuracy. The magnitude change of the magnetic flux density in the magnetoelectric conversion element can be increased, and a magnetic rotation sensor device with high sensitivity can be realized. In addition, no new rotor processing equipment is required, and the cost is low. In the magnetic rotation sensor device according to the third aspect of the present invention, the first and second magnets and the magnetoelectric conversion element are arranged so as to be orthogonal to the axis of the rotor.
The gap between the magnetoelectric conversion element and the rotor can be reduced and the rotor can be assembled with high accuracy. Further, since the first magnet and the second magnet are arranged on the same axis so that the same magnetic poles face each other, it is possible to increase the magnitude change of the magnetic flux density in the magnetoelectric conversion element, and the magnetic rotation sensor device with high sensitivity. Is possible. In addition, there is no need for a position adjustment mechanism, so there is no risk of performance degradation or damage due to foreign matter being caught.

[Brief description of drawings]

FIG. 1 is a sectional view showing a first embodiment of a magnetic type rotation sensor device according to the present invention.

2 is a detailed view of a magnet portion of the magnetic rotation sensor device shown in FIG. 1, where (a) relates to a magnet 24a and (b) relates to a magnet 24b.

3 is an enlarged view of a sensor portion of the magnetic rotation sensor device shown in FIG. 1, where (a) is a front view and (b) is D of (a).
It is a D sectional view.

FIG. 4 is a Hall IC of the magnetic rotation sensor device shown in FIG.
It is a figure explaining the magnetic force line which passes 25, (a) is a conventional magnetic rotation sensor apparatus, (b) is a magnetic rotation sensor apparatus of 1st Example of this invention.

5 is a Hall IC of the magnetic rotation sensor device shown in FIG.
It is a figure explaining the magnetic force line which passes 25, (a) is a conventional magnetic rotation sensor apparatus, (b) is a magnetic rotation sensor apparatus of 1st Example of this invention.

6 is a Hall IC of the magnetic rotation sensor device shown in FIG.
It is a figure which shows the output voltage of 25, (a) is a conventional magnetic rotation sensor apparatus, (b) is a magnetic rotation sensor apparatus of 1st Example of this invention.

FIG. 7 is a diagram showing a circuit configuration and a two-wire signal transmission system of the magnetic rotation sensor device shown in FIG.

FIG. 8 is a sectional view showing a second embodiment of the magnetic rotation sensor device according to the present invention.

9A and 9B are enlarged views of a sensor portion of the magnetic rotation sensor device shown in FIG. 8, where FIG. 9A is a front view and FIG. 9B is an E of FIG.
It is an E sectional view.

FIG. 10 is a hall I of the magnetic rotation sensor device shown in FIG.
It is a figure explaining the magnetic force line which passes C25, (a), when the non-magnetic part 633 opposes Hall IC25,
(B) is the case where the magnetic portion 62 faces the Hall IC 25.

FIG. 11 is a perspective view showing a first example of a conventional magnetic rotation sensor device.

FIG. 12 is a perspective view showing a second example of a conventional magnetic rotation sensor device.

[Explanation of symbols]

1, 5, 6, 20, 60 Rotor 1a, 5a, 6a, 22, 63 Recess 1b, 5b, 6b, 21, 62 Convex 2, 10, 25 Hall IC 3, 8, 9, 24a, 24b Magnet 20a, 60a Fitting part 23 Magnetic rotation sensor 61 Base part 223,631 Non-magnetic part 241,242,243,244,245,246,2
47 magnetic field lines

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toru Kita 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd.

Claims (3)

[Claims] 1. A first magnet, a second magnet arranged so that a magnetic pole axis intersects with a magnetic pole axis of the first magnet at a predetermined angle, and a magnetic line of force of the first magnet is detected. A magnetic-electric conversion element and a rotor whose rotation state is detected by the magnetic-electric conversion element are provided, and the magnetic-electric conversion element is provided in the rotor at a portion where magnetic lines of force of the first magnet and the second magnet overlap each other. A non-magnetic portion that repels the magnetic force lines of the first magnet and the second magnet so that the magnetic force lines that pass therethrough and the magnetic field lines that pass through the magnetoelectric conversion element increase. A magnet and a magnetic portion that collects the magnetic lines of force of each of the second magnets are provided, while the magnetic pole axis of either one of the first magnet and the second magnet is arranged substantially perpendicular to the rotor. Porcelain characterized by Wherein the rotation sensor device. 2. The magnetic rotation sensor device according to claim 1, wherein the first magnet and the second magnet are arranged such that an angle formed by their magnetic pole axes is about 90 degrees. Characteristic magnetic rotation sensor device. 3. A rotor having an annular base portion and a plurality of magnetic portions formed in an annular shape at a predetermined pitch so as to project at the peripheral portion of the base portion in the rotation axis direction, and the same magnetic pole with the magnetic portion sandwiched therebetween. A magnetic rotation sensor, comprising: a pair of magnets arranged so as to face each other; and a magnetoelectric conversion element provided between any one of the pair of magnets and the magnetic portion. apparatus.