JP2000310647A - Rotary detection sensor and its mounting structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sensor where the degree of freedom for mounting the sensor is higher than that of a conventional sensor while the sensor cannot be affected from the surroundings. SOLUTION: For the sensor, the mounting structure of a rotary detection sensor is equipped with a rotary member 10, a fixing member 30 that is provided outside the rotary member 10 and is fixed to a non-rotation side, bearings 16, 18, 38, and 40 that are included between the fixing member 30 and the rotary member 10, a control member 22 that controls the axial direction of the bearing, a rotor 6 that is integrated with the rotary member 10 being mounted at a rotation side for rotating, and a sensor 1 that has flux generation and detection parts, is arranged opposite to the rotor 6, and detects change in flux when the rotor is rotated. In this case, the rotor 6 is an annular member with a L-shaped section, and is provided near the outer periphery of the rotor 6 opposingly in an axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation detection sensor for detecting rotation of a rotating member and a mounting structure for the rotation detection sensor.

[0002]

2. Description of the Related Art Conventionally, as this type of sensor, a wheel speed sensor for detecting rotation of a wheel is known in the field of vehicles. The wheel speed sensor is provided with a rotor having a slit or a gear surface that changes the magnetic flux density on the wheel side, and generates magnetic flux by a magnetic flux generating unit in a non-contact manner in close proximity to the rotor, and changes in magnetic flux according to the rotation state of the rotor. A sensor having a detection unit for detecting is provided on the non-rotating vehicle body side to detect the rotation state of the rotor by changing the magnetic flux with the rotation of the rotor.
No. 185.

The wheel speed sensor shown here is disposed on an outer wheel mounted on a vehicle body, a cylindrical hub on which wheels are mounted, an inner wheel provided around the hub, and between the outer wheel and the inner wheel. A plurality of rolling members for rotatably supporting the inner ring, a nut member fixed to the hub and screwed to the hub so as to rotate integrally, and an outer ring surrounding the nut member A cover attached to the
It consists of a pulsar (gear surface) that rotates integrally with the hub, and a sensor that is arranged close to the pulsar and detects the number of revolutions of the pulsar. The sensor is mounted inside the cover and the outer peripheral surface of the nut and the inner periphery of the cover. It is arranged in the space formed by the surface. In this configuration, the gear surface serving as the pulsar is provided integrally with the nut that regulates the axial movement of the hub.

[0004] Further, in a wheel speed sensor disclosed in Japanese Patent Application Laid-Open No. 10-104249, a sensor having a magnetic flux generating unit and a detecting unit for a rotor is disclosed, and the rotation of the rotor shown here is detected. The magnetoelectric conversion element is integrally formed directly with a resin together with a magnet for generating a magnetic flux.

[0005]

However, in the device disclosed in Japanese Patent Application Laid-Open No. 7-5185, the sensor arrangement is screwed into a screw portion provided in the axial direction of the inner ring, and the axial movement of the hub is performed. And a cover that covers the entire nut.

[0006] The nut functions as a regulating member for regulating the movement of the hub in the axial direction, and is usually made of a metal material.
In the above configuration, there is a nut fastening portion near the pulsar. The tightening portion of the nut usually has a polygonal (hexagonal) shape, and when the nut rotates, the magnetic flux changes by the tightening portion, and the tightening portion of the nut affects the magnetic flux at the position where the sensor is disposed. It will be. Also, in this configuration,
Since the sensor is mounted inside the cover and is arranged in the space formed by the outer peripheral surface of the nut and the inner peripheral surface of the cover, the radial direction becomes larger, and the wheel speed sensor is When mounted on a suspension member, there is a possibility that interference will occur with the suspension member.

Further, in the wheel speed sensor disclosed in Japanese Patent Application Laid-Open No. 10-104249, since the magneto-electric conversion element and the magnet are directly molded by resin molding, stress is applied to the detection element and the characteristics are deviated. It can happen. Further, since the magnetoelectric conversion element is molded with resin, the distance from the rotor is increased.

Accordingly, the present invention has been made in view of the above problems, and a first object is to provide a sensor mounting structure which is not affected by the surroundings, and a second object is to prevent the sensor from increasing in the radial direction. A third problem is to improve the reliability as a sensor.

[0009]

The first technical means taken to solve the above-mentioned problems is a fixed member, a rotating member rotatably supported by the fixed member via a bearing member, and
A regulating member fixed to the rotating member and regulating relative movement of the rotating member and the fixed member in the axial direction; and a magnetic property changing section fixed to the regulating member or the rotating member and periodically changing its magnetic property in the circumferential direction. In a rotation detection sensor including a rotor and a detection unit disposed to face the magnetic characteristic change unit of the rotor, the rotor has one end fixed to a regulating member or a rotating member, and the other end regulated. It has a cylindrical shape extending in the axial direction so as to surround the member, and the other end has the magnetic characteristic change portion facing the detection in the axial direction.

With the above arrangement, the rotor has a cylindrical shape having one end fixed to the regulating member or the rotating member and the other end extending in the axial direction so as to surround the regulating member, and the other end having the detecting portion. The provision of the magnetic characteristic changing portion facing in the axial direction has an L-shaped cross section, so that the magnetic characteristic is not affected by the regulating member as in the related art. In this case, it is possible to dispose the sensor in the axial direction of the rotor, so that the sensor is not increased in the radial direction as compared with the related art, and the degree of freedom in mounting the sensor is improved.

In this case, the sensor is provided integrally with the cover fixed to the fixing member so as to cover the rotor, and the cover is press-fitted and fixed to the fixing member, so that the sensor can be easily attached to the fixing member. Becomes possible.

A second technical means taken to solve the above-mentioned problems is a sensor having a stepped portion for detecting rotation of the rotor in a non-contact manner, and a protection having an opening conforming to the shape of the sensor. The sensor is housed in the opening, the resin is molded into the opening, and the resin is turned to the step by resin molding, whereby the sensor and the protection member are integrally molded to obtain a resin molded product.

With the above arrangement, the sensor is housed in the opening conforming to the shape of the sensor, resin is molded, and the resin is turned to the step by resin molding so that the sensor and the protection member are integrally molded. Since the sensor is molded with the resin in the protective member, the influence of the stress due to the resin molding is protected by the protective member, and the step portion of the sensor is fixed with the resin and integrally molded. The reliability and performance of the sensor is improved.

In this case, if the signal line is output from the sensor in parallel with the step and the step and the signal line are fixed by resin molding, the sensor is fixed at both ends in the step and the signal line. , And can be securely fixed.

The length of the resin molded product in the axial direction can be reduced by connecting the L-shaped terminal to the signal line by surface contact.

[0016]

An embodiment of the present invention will be described below with reference to the drawings. Here, the vehicle wheel speed sensor SE
N will be described, but is not limited thereto.

FIG. 1 is a diagram showing a mounting structure of a wheel speed sensor SEN according to an embodiment of the present invention. Referring to FIG. 1, the hub inner ring 10 has a cylindrical shape having two steps in the axial direction.
2 and a flange portion 14. In the flange portion 14, wheels are fixed to through holes 14a provided at several places (five places) by fastening members such as bolts.
Bearings 16 and 38 are provided on the outer peripheral surface of the main body portion 12 of the hub inner ring 10, and a regulating groove 12a corresponding to the outer diameter of the bearing for regulating the axial movement of the bearings 16 and 38 is formed in the circumferential direction. Is formed. The main body 12 is provided with a stepped portion 12 in a circumferential direction at a position apart from the regulating groove 12a in the axial direction.
b at the end 12b in the axial direction.
Is provided, and an annular regulating member 22 that regulates the axial movement of the hub inner ring 10 by regulating the bearings 18 and 40 is provided in the step portion 12b, and the axial direction is regulated. The restricting member 22 includes a screw portion 12 a provided at an end of the main body 12.
, And the axial movement of the bearings 18 and 40 is regulated by the back surface 50 a of the nut 50. In this state, the sizes of the annular regulating groove 12a provided in the main body 12 and the annular regulating groove 22a provided in the regulating member 22 are bilaterally symmetric with respect to a plane perpendicular to the rotation axis of the hub inner ring 10. In addition, when the regulating member 22 is attached to the hub inner ring 10, the outer diameters at the contact portions between the regulating member 22 and the hub inner ring 10 are the same as each other.

On the other hand, a hub outer ring 30 having a hollow cylindrical shape is provided outside the main body portion 12, and the hub outer ring 30 is a non-rotating side suspension member (such as a suspension tower) of the vehicle at the flange portion 32. Attached to Bearings 16, 1 are provided between the annular regulating grooves 12a, 22a and the regulating grooves 22a provided in the regulating member 22.
A plurality of 8, 38, 40 are arranged in the circumferential direction in two rows, and the bearings 16, 18, 38, 40 are supported by rolling grooves 24, 36 provided in the inner diameter of the hub outer ring 30. I have. With such a configuration, the bearings 16, 18, 38, and 40 arranged in two rows in the axial direction roll in the circumferential direction,
Although the hub inner ring 10 is rotatable with respect to the hub outer ring 30, the movement of the hub inner ring 10 and the hub outer ring 30 in the axial direction is restricted because the regulating member 22 is regulated by the nut 50 in the axial direction.

Further, an annular seal member 42 is interposed between the end portion of the hub outer ring 30 on the flange portion 14 side and the main body portion 12 for the purpose of preventing water droplets from entering the bearings 16 and 38. I have. The seal member 42 is formed by baking rubber or the like on the annular stainless steel and has a function of reliably preventing moisture from entering the inside.

On the other hand, an annular rotor 6 made of a magnetic member and having an L-shaped cross section is press-fitted around the regulating member 22 so as to surround the regulating member 22. The rotor 6 has a regulating member 22 on a surface perpendicular to the rotation axis of the hub inner ring 10.
A plurality of radial slits 6a (here, a plurality of radial slits 6a) serving as magnetic characteristic changing portions are provided near the outer periphery of the rotor 6 so as not to be affected by the magnetic flux accompanying the rotation of the nut 50 that restricts the axial movement of the nut 50.
The number of slits is 48 (see FIG. 2). The sensor 1 detects the rotational state of the rotor 6 in a non-contact manner by a change in magnetic flux, facing the slit 6a formed in the circumferential direction. The portions (rotor-facing surfaces) are closely arranged at a predetermined distance from each other, and the detection accuracy can be improved by closely arranging them.

In this embodiment, the rotor 6 is directly mounted on the outer periphery of the regulating member 22 by press-fitting. However, for mounting, a member may be interposed between the rotor 6 and the fastening instead of press-fitting. It may be fixed by a member. In this case, it may be directly attached to the hub inner ring 10 (rotation side). Regarding the shape of the rotor 6, it is not necessary that the slit 6 a is formed so as to face the sensor 1, as long as the magnetic flux is changed by the rotation of the rotor 6. Even if it is formed, the rotation state of the rotor 6 can be detected.

The sensor 1 internally or integrally has a magnetic flux generating section having a magnet and a detecting section having a Hall IC (Hall element), and generates a magnetic flux around the magnetic flux generating section to detect a change in the magnetic flux. Non-contact detection by the unit. That is,
When the wheel rotates, the hub inner ring 10 to which the wheel is fixed rotates with respect to the hub outer ring 30. When the hub inner ring 10 rotates, the rotor 6 having the circumferentially provided slit 6a that rotates integrally with the hub inner ring 10 rotates, and the radial slit 6a rotates.
The magnetic flux generated by the magnet of the magnetic flux generating portion of the sensor 1 receives the rotation of the slit 6a and changes the magnetic flux (magnetic flux density), so that the output from the Hall IC periodically changes. As a result, the rotation speed of the wheel is reduced. Is detected. In this case, the sensor 1 may be a Hall IC, a magnetoresistive element, a GMR, or the like.

The sensor 1 is resin-molded integrally with a cover 7 covering the outer periphery of the rotor 6 and the connector CT. The cover 7 is pressed into the inner diameter of the hub outer ring 30 so as to close one opening of the hub outer ring 30. ing. The end of the cover 7 is press-fitted to a position where an annular flange 7a provided on the outer periphery is provided. In this manner, in a state where the cover 7 is press-fitted and fixed to the hub outer ring 30, the slit 6a of the rotor 6 and the sensor 1 face each other in a parallel state and are separated from each other by a predetermined distance.

The cover 7 has the connector CT as described above.
Are also integrally formed, and when a voltage is applied to the sensor 1,
In order to detect a rotation signal from the sensor 1, a conductor signal line 9 extends out of the sensor 1, and the signal line 9
Terminal 3 is electrically connected to the connector CN.
To detect the rotation signal of the rotor 6 via the.

Next, a resin molded product having the sensor 1 and the cover 7 and the connector CT will be described.

The sensor 1 has a magnet as a magnetic flux generating unit and a Hall IC as a detecting unit, and has a step 1a in a part of its outer shape. On the other hand, the protection member 5 for accommodating the sensor 1 is formed by resin molding or the like so that the connector end is exposed by insert molding or assembling the L-shaped connector 3 in advance. Resin (for example, PPS,
(Nylon 66, resin such as PBT). In this case, insert the L-shaped terminal into the resin mold,
A primary molded product shown in FIG. 3A in which the opening surface of the opening 5a and the bottom 3a of the L-shaped terminal 3 are flush with each other by insert molding. After the primary molded product is completed, the sensor 1 is fitted into the opening 5a of the protection member 5, and the sensor 1 is temporarily fixed with an adhesive or the like. In this case, the signal line 9 from the sensor 1 and the bottom 3a of the terminal 3 are brought into contact with each other and brought into surface contact with each other. To electrically connect the terminal 3 and the signal line 9 by resistance welding. After that, the sensor 1 is provided inside by secondary molding using the same resin as used in the primary molding, and the cover 7
A secondary molded article having the connector CT and the connector CT is formed (see FIG. 3C). In this case, the resin used in the secondary molding may not be the same as the resin used in the primary molding.

During the secondary molding, the step 1a of the sensor 1
If the signal line 9 is output from the opposite direction in parallel with the resin and the resin goes around to the step portion 1a and the step portion 1a and the signal line 9 are fixed, stable fixing can be performed, and the sensor 1 is opened 5a. Since the protection is performed by the protection member 5 that conforms to the above, no stress is applied, and both are fixed by the step portion 1a and the signal line 9, so that the sensor characteristics can be prevented from being affected. Further, by feeding the resin to the step portion 1a of the sensor 1 during the secondary molding, the sensor 1 can be fixed while suppressing the stress applied to the sensor 1 together with the protective member 5 during and after molding. Further, the rotor 6
When the sensor 1 and the sensor 1 are opposed to each other, the detection surface on the rotor side of the sensor 1 can be disposed close to and exposed to the rotor 6, so that the distance from the rotor 6 is shortened and the detection accuracy is improved.

Furthermore, the signal line 9 and the terminal 3 are electrically connected to the signal line 9 from the sensor 1 by resistance welding or the like while the L-shaped terminal 3 is released in a radial direction perpendicular to the axial direction (rotation axis direction). After secondary connection, perform secondary molding,
Since a resin molded product is obtained, the axial length of the connector CT can be minimized.

[0029]

According to the first aspect of the present invention, the rotor has a cylindrical shape having one end fixed to the regulating member or the rotating member and the other end extending in the axial direction so as to surround the regulating member. Since the detecting section has the magnetic property changing section opposed in the axial direction, the cross section has an L-shape, and the magnetic property is not affected by the regulating member as in the related art. In this case, it is possible to dispose the sensor in the axial direction of the rotor, so that the sensor is not increased in the radial direction as compared with the related art, and the degree of freedom in mounting the sensor is improved.

In this case, the sensor is provided integrally with the cover fixed to the fixing member so as to cover the rotor, and the cover is press-fitted and fixed to the fixing member, so that the sensor can be easily attached to the fixing member. Can be.

According to the second aspect of the present invention, the sensor is housed in an opening conforming to the shape of the sensor, resin molding is performed, the resin is turned to the step by resin molding, and the sensor and the protection member are integrally molded. By doing so, the sensor is molded into the resin in the protective member, so the effect of the stress due to the resin molding is protected by the protective member, and the step portion of the sensor is fixed with the resin and integrally molded, so the stress Since the sensor characteristics do not change, the reliability and performance of the sensor are improved.

In this case, if the signal line is output from the sensor in parallel with the step and the step and the signal line are fixed by resin molding, the sensor is fixed at both ends in the step and the signal line. , And can be securely fixed.

Further, in the resin molded product, if the L-shaped terminal is connected to the signal line by surface contact, the axial length of the connector can be reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a mounting structure of a rotation detection sensor according to an embodiment of the present invention.

FIG. 2 is a plan view showing a slit shape of a rotor in a rotation detection sensor mounting structure according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a method of manufacturing a cover including a rotation detection sensor according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sensor 1a Step part 3 Terminal 5 Protective member (primary molded product) 6 Rotor 6a Slit (magnetic characteristic change part) 7 Cover (secondarily molded product) 9 Signal line 10 Hub inner ring (rotating member) 21 Opening 22 Regulatory member 30 Hub Outer ring (fixing member) 16, 18, 38, 40 Bearing (rolling member) 50 Nut (regulating member)

Claims (5)

[Claims] A fixed member, a rotating member rotatably supported by the fixed member via a bearing member, and a fixed member fixed to the rotating member, which regulates relative movement of the rotating member and the fixed member in the axial direction. A regulating member, a rotor fixed to the regulating member or the rotating member, and having a magnetic property changing portion for periodically changing a magnetic property thereof in a circumferential direction, disposed so as to face the magnetic property changing portion of the rotor; A rotation detection sensor comprising: a detection unit provided in the rotation detection sensor, wherein the rotor has one end fixed to the restriction member or the rotation member, and the other end side extends in the axial direction so as to surround the restriction member. An attachment structure for a rotation detection sensor, wherein the attachment structure has a cylindrical shape, and the other end includes the magnetic characteristic change portion in which the detection portion faces in the axial direction. 2. The rotation detection sensor mounting structure according to claim 1, wherein the sensor is provided integrally with a cover fixed to the fixing member so as to cover the rotor. 3. A sensor having a step and detecting rotation of the rotor in a non-contact manner, and a protection member having an opening conforming to the shape of the sensor, wherein the sensor is housed in the opening and resin molding is performed. A rotation detection sensor, wherein a resin is fed to the step by resin molding, and the sensor and the protection member are integrally molded to obtain a resin molded product. 4. The rotation detection sensor according to claim 3, wherein a signal line is output from the sensor in parallel with the step, and the step and the signal line are fixed by resin molding. 5. The resin molded product has an L line on the signal line.
A rotation detection sensor, wherein a character-shaped terminal is connected by surface contact.