JP2003254985A - Rolling bearing unit having rotating speed detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve reliability of rotating speed detection by preventing a foreign substance from entering a portion between a detection part of the rotating speed sensor 24a and a part to be detected of an encoder 33 even before assembling to an automobile. <P>SOLUTION: A sensor holder 34 is externally fitted and secured to an inner end part of an outer wheel 1. The sensor holder 34 comprises a fitting cylinder 42 of an L-shape in cross section and a holding part 43 which is made of a synthetic resin having enclosed therein the rotation speed sensor 24a connected to the fitting cylinder 42. An inner diameter side part of a radial outside face of an inward flange 45 constituting the fitting cylinder 42 and an outer diameter side part of an inside end face of an inner ring 3 to which the encoder 33 is externally fitted and secured are faced each other via a minute crevice 47 along the whole circumference. <P>COPYRIGHT: (C)2003,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION [0001] BACKGROUND OF THE INVENTION 1. Field of the Invention
Rolling bearing unit with device for suspending the wheels of an automobile
And the rotation speed of this wheel.
Used to detect degrees. [0002] 2. Description of the Related Art The wheels of an automobile rotate with respect to a suspension device.
A rolling bearing unit is used for the support.
Also, anti-lock brake system (ABS) or truck
To control the traction control system (TCS)
Needs to detect the rotational speed of the wheels. Because of this,
A rotation speed detector is incorporated in the above rolling bearing unit.
Rolling bearing unit with rotating speed detector
While supporting the wheels rotatably with respect to the suspension,
Detecting the rotational speed of the wheel of a vehicle has been widely performed in recent years
It is like. [0003] A rotation speed detecting device used for such a purpose.
As an example of a mounted rolling bearing unit, see Japanese Unexamined Patent Application Publication No. 9-21
No. 822 discloses a structure as shown in FIGS.
ing. With this conventionally known rotation speed detection device
Rolling bearing unit is supported and fixed to a suspension device (not shown)
On the inner diameter side of the outer ring 1 that does not rotate during use.
Can rotate the hub 2 and the inner ring 3 constituting the inner ring equivalent member
I support it. That is, the outer race 1 is provided on the outer peripheral surface.
A first flange 4 for attaching the wheel 1 to the suspension,
The inner peripheral surface has multiple rows of outer raceways 5, 5, respectively.
The hub 2 is located outside the outer peripheral surface (with respect to the axial direction,
Outside of the vehicle in the width direction when the vehicle is assembled. Same here
Same. Left side of each figure except FIGS. ) Wheels near the edge
Is provided with a second flange 6 for supporting the second flange 6. Also, above
A first inner raceway 7 is formed at an intermediate portion of the outer peripheral surface of the hub 2
And the same (with respect to the axial direction,
In the center of the vehicle in the width direction. Same here. Figures 2 and 7
Excluding the right side of each figure. ) Small diameter step 8 formed near the end
The inner ring having a second inner ring raceway 9 formed on its outer peripheral surface.
3 is fitted outside. Further, each of the outer raceways 5, 5 and each of the inner raceways 5
Between the roads 7 and 9, a plurality of rolling elements 1
0 and 10 are provided rotatably, and the inner ring side of the outer ring 1 is
The hub 2 and the inner ring 3 are rotatably supported. Also, above
Between the outer end opening of the outer ring 1 and the outer peripheral surface of the intermediate portion of the hub 2
A first seal ring 11 is provided therebetween. This first
The seal ring 11 is a cylinder on which the balls 10 and 10 are installed.
The outer end opening of the cylindrical space 12 is closed, and the inside of the cylindrical space 12 is closed.
Grease leaks out or foreign matter present outside
From entering the cylindrical space 12. still,
In the illustrated example, a ball is used as the rolling element 10,
Rolling bearing unit with rotation speed detector for heavy vehicles
For knits, use tapered rollers as rolling elements
In some cases. A drive shaft 14 is provided in the center hole 13 of the hub 2.
And the outer peripheral surface of the drive shaft 14 and the center hole
13 is made spline-engageable with the inner peripheral surface. Automatic
When the vehicle is running, it is provided at the inner end of the drive shaft 14.
Constant velocity joint housing 1 constituting a speed joint
The drive shaft 14 is rotationally driven through the drive shaft 5. On the other hand, the inner end of the inner ring 3
An outer peripheral surface of a portion deviating from the ring raceway 9 and an inner end of the outer ring 1
A set seal 16 is provided between the inner circumferential surface and the cylindrical inner surface.
The inner end opening of the space 12 is closed. This set seal 16
Is a rotary seal that is externally fitted and fixed to the inner end of the inner ring 3.
17 and a fixed side internally fixed to the inner end of the outer ring 1.
And a seal ring 18. In addition, each of these seal phosphorus
Each of the rings 17 and 18 is formed in an annular shape with an L-shaped cross section.
Core metals 19a, 19b, and the respective core metals 19a, 19b
Elastic members 20a and 20b having their respective base ends connected to
Is provided. And the tip of each of the elastic members 20a and 20b
The edge is a core metal that constitutes the seal rings 18 and 17 on the other side.
19b and 19a are in sliding contact with each other. The pair of seal rings 17, 18
That is, of the core metal 19a constituting the rotation-side seal ring 17,
The side surface (the right side surface in FIG. 1) is an encoder 21. This
Encoder 21 is made of a magnetic material such as a steel plate into an annular shape.
A plurality of notches 22, 22 are formed in the outer peripheral edge of the
Comb-shaped by forming at equal intervals in the circumferential direction
And magnetic properties are alternately and equally spaced in the circumferential direction.
It has been changed to the interval. On the other hand, the outer peripheral surface of the outer
By pressing the plate, the cross section is almost L-shaped and the whole
Corresponds to the sensor holder described in the claims, made in an annular shape
The cover 23 to be fitted is externally fixed. And this hippo
, A rotation speed sensor 24 is supported inside. This
Of the rotation speed sensor 24 is rectangular in cross section and the whole is formed in an arc shape.
The cover 23 is embedded in the formed synthetic resin 25.
To the holding portion 26 formed in a part of the circumferential direction of
I have. In this state, the rotation speed sensor 24 detects
The protruding part is the detected part of the encoder 21,
A part of the inner surface in the circumferential direction is opposed via a minute gap 27.
ing. The rotation speed sensor 24 is arranged in the axial direction (FIG. 6).
Of the permanent magnet 28 magnetized over the
And a magnetic detecting element 29 such as an IC and a magnetic resistance element.
Then, for extracting the signal of the rotation speed sensor 24,
Disconnect the harness 30 from the holding portion 26 in the circumferential direction.
From the harness take-out part 31
-23 taken out. On the inner peripheral surface of the inner end of the cover 23, a second
A seal ring 32 is provided over the entire circumference. Soshi
Then, the drive shaft 14 is inserted into the center hole 13 of the hub 2.
In this state, a part of the outer peripheral surface of the drive shaft 14 is
The outer surface of the shoulder of the joint housing 15 and the second
To make the leading edge of the seal ring 32 slide.
You. [0011] The above-mentioned publication having the structure described above
According to the rolling bearing unit with the rotation speed detecting device,
A suspension device supporting the wheel fixed to the hub 2 and supporting the outer ring 1
It can be supported rotatably with respect to the installation. Also, with the rotation of the wheels
With the inner ring 3 externally fitted and fixed to the inner end of the hub 2
When the rotor 21 rotates, the magnetic detection element of the rotation speed sensor 24
Since the density of the magnetic flux sent to the element 29 changes, this rotation speed
The resistance value and output voltage of the degree sensor 24 change. As described above, the resistance value of the rotation speed sensor 24,
Alternatively, the frequency at which the output voltage changes is the rotational speed of the wheel
Is proportional to Therefore, the output signal of the rotation speed sensor 24 is
Signal is input to a controller (not shown).
The degree can be obtained and ABS and TCS can be controlled appropriately. In the case of the conventional structure shown in FIGS.
A second seal ring 32 is provided on the inner end of the inner peripheral surface of the bar 23.
The tip of the second seal ring 32 is
Outer peripheral surface of base end of shaft 14 and housing for constant velocity joint
The outer surface 15 is freely slidable over the entire circumference. This
Therefore, when using a rolling bearing unit with a rotation speed detection device
The inner peripheral surface of the cover 23 and the outer peripheral surface of the drive shaft 14
Between the inner surface of the encoder 21 and the rotational speed.
Magnetic powder or the like in the gap 27 between
Foreign matter can be prevented from entering. Therefore, this
The permanent magnet of the rotation speed sensor 24 is
Foreign matter, such as magnetic powder, adheres to the vicinity of
It is possible to prevent the accuracy of speed detection from deteriorating. [0014] SUMMARY OF THE INVENTION The rotational speed detection as described above is performed.
The rolling bearing unit with an extension device is the same as the rolling bearing unit.
After being built by the manufacturer, it is transported to the finished car manufacturer
You. And in this finished product manufacturer, the center hole 1 of the hub 2
3 through the drive shaft 14, and the inner peripheral surface of the center hole 13
Of the drive shaft 14 is spline-engaged. or,
Second seal ring 32 connected to the inner peripheral surface of cover 23
Of the drive shaft 14 at a constant velocity
By sliding on the outer surface of the housing 15
The rotation speed sensor 24 and the inner surface of the encoder 21
The gap 27 between the detecting part and the detecting part is sealed. On the other hand,
Equipped with the above rotation speed detector on the assembly line of the finished product manufacturer
This automatic, including during the transportation of the rolling bearing unit,
The above-mentioned drive inside the center hole 13 in the finished car manufacturer
Before the shaft 14 is inserted, the encoder 21
2 between the inner surface of the motor and the detection unit of the rotation speed sensor 24
7 is not sealed from the outside, and foreign matter enters the gap 27.
May be As described above, foreign matter enters the gap 27 and
In such a case, the detection accuracy of the rotation speed sensor 24 deteriorates.
there is a possibility. In particular, as shown in FIGS.
The sensor 24 detects the rotational speed using magnetism.
In this case, the magnetic powder enters the gap 27 and
In this case, the detection accuracy of the rotation speed sensor 24 is deteriorated.
It will be easier. In the case of the structure shown in FIGS.
Since the permanent magnet 28 is incorporated in the sensor 24,
When foreign matter such as magnetic powder enters the space, the cover 23
The foreign matter adheres near the permanent magnet 28 on the outer surface of the
May be On the other hand, the rotation speed sensor
Without magnets, wear in alternate directions in the circumferential direction.
The structure that composes the encoder with magnetized permanent magnets is also known.
Have been. In this case, the magnetic powder
Configures the above encoder when foreign matter such as
This foreign matter adheres to the side surface of the permanent magnet,
There is a possibility that the detection accuracy of the degree sensor is deteriorated. Of the present invention
The rolling bearing unit with rotation speed detector
It was invented in view of circumstances. [0015] SUMMARY OF THE INVENTION A rotational speed detecting device according to the present invention.
The rolling bearing unit is a conventional rolling bearing unit shown in FIGS.
Like the structure, the first to attach to the suspension on the outer peripheral surface
Of the outer ring raceway on the inner peripheral surface.
The outer ring that does not rotate during use and the car near the outer end of the outer peripheral surface
Place a second flange to support the wheel, also in the middle
Each having an inner raceway facing the outer raceway,
Driven in use by the drive shaft inserted in the hole
Between the outer ring raceway and the inner raceway,
A plurality of rolling elements provided in the
At the part of the outer peripheral surface of the inner end that deviates from the inner raceway,
In the circumferential direction of the part to be detected, supported concentrically with the ring equivalent member
With the characteristics related to each other alternately and at equal intervals
And a portion facing the encoder at the inner end of the outer ring
Sensor holder fixed to and supported by this sensor holder
And the detection part faces the detection part of this encoder.
And a rotation speed sensor. In particular, rolling with a rotation speed detecting device of the present invention
In the bearing unit, the inner end surface of the inner ring equivalent member
In addition, a part of the above-mentioned sensor holder or a support
A part of another member that is held close to the entire circumference
Is in sliding contact. [0017] According to the present invention, the rotational speed detecting device of the present invention is constructed as described above.
According to the rolling bearing unit, the inner race
Even before the drive shaft is inserted through the center hole of this member,
Between the detecting part of the speed sensor and the detected part of the encoder
Per minute to prevent foreign matter from entering,
The reliability of detection can be improved. [0018] 1 to 3 show an embodiment of the present invention.
1 shows a first example. It should be noted that the feature of the present invention is equivalent to the inner ring
Before the drive shaft 14 is inserted through the center hole 13 of the member
Also, the detection unit of the rotation speed sensor 24a and the encoder 33
This prevents foreign matter from entering the area between the
To improve the reliability of the detection accuracy of the rotational speed sensor 24a
The structure of the sensor holder 34 and the member equivalent to the inner ring
It is in the point which did. Regarding the structure and operation of other parts
Is almost the same as that of the conventional structure shown in FIGS.
Therefore, the same parts are denoted by the same reference numerals, and the description will be duplicated.
Are omitted, and the features of the present invention and the above-described conventional structure will be described below.
The following description focuses on the structure of the different part. In the case of the present embodiment, an inner ring equivalent member is mounted together with the hub 2.
An encoder 33 is provided at the inner end of the inner ring 3,
The outer fitting is fixed concentrically with the ring 3. This encoder 33
Comprises a support ring 35 and an encoder body 36. this
The support ring 35 is pressed on a magnetic metal plate such as SPCC.
By processing, the whole is formed in an annular shape with an L-shaped cross section
are doing. Then, this support ring 35 is attached to the inside of the inner ring 3.
The outer ring is fitted and fixed concentrically with the inner ring 3 by tight fitting at the end.
You. The encoder body 36 is made of, for example, ferrite.
A ring part constituting the support ring 35 is formed by mixing rubber mixed with powder.
37 is attached to the inner surface in the axial direction by baking or the like.
You. This encoder body 36 is magnetized in the axial direction and
The magnetization direction is alternately changed at regular intervals in the circumferential direction.
It is making it. Therefore, the detected part of the encoder 33
On the inner surface in the axial direction, the S pole and the N pole are arranged in the circumferential direction.
Are arranged alternately and at equal intervals. Also, this d
The encoder 33 is externally fitted and fixed to the inner end of the inner ring 3.
Thus, the axial inner surface of the encoder body 36 and the inner ring 3
The inner end face is located on substantially the same plane. On the other hand, a seal ring is provided on the inner end of the outer race 1.
38 is fixed inside. This seal ring 38 is
A metal core 39 having a substantially L-shaped surface and formed entirely in an annular shape,
An elastic member 40 having a base end coupled to a cored bar 39.
You. Then, the three seal lids provided on the elastic member 40 are provided.
The encoder 33 is connected to the leading edges of the pumps 41a to 41c.
Sliding contact with the outer peripheral surface and the axially outer surface of the support ring 35 formed.
ing. With this configuration, a plurality of balls 10, 10 are installed.
The inner end opening of the cylindrical space 12 is closed. The inner end of the outer race 1 is
It protrudes inward in the axial direction by about 1 mm from the inner end face. So
Then, an annular sensor holder 3 is attached to the inner end of the outer ring 1.
4 is attached. This sensor holder 34 is
2 and a holding portion 43 connected and fixed to the fitting cylinder 42.
I can. The fitting cylinder 42 is formed on a metal plate such as SPCC.
By pressing, etc., the cross section is L-shaped and the whole is annular
The fitting tube portion 44 and the fitting tube portion 4
4 and an inward flange 45 bent from the base end edge.
And the inner diameter d of this inward flange 45₄₅Of the inner ring 3
Outer diameter D of inner end _Three Slightly smaller than (d₄₅<D
_Three ). In addition, a part of the inward flange 45, the encoder
The part facing the circumferential part of the inner surface of the main body 36 has a sector shape.
Etc. are formed. The holding section 43 is made of a synthetic resin and has a circular shape.
It is formed in an arc shape and encloses the rotational speed sensor 24a.
Buried. The inward flange forming the fitting cylinder 42
Circumferential direction of the inner side surface in the axial direction (the right side surface in FIGS. 1 and 3)
Part (preferably the top part when used)
The holding portion 43 is connected and fixed by integral molding.
You. Furthermore, the inside of the through hole 46 formed in the inward flange portion 45
, A part of the holding portion 43 enters. The rotation speed sensor 24a is a Hall element.
Element, magnetoresistive element (MR element), etc.
A magnetic sensing element that changes its characteristics
I incorporating a waveform shaping circuit for adjusting the output waveform of the slave
C. Such a rotational speed sensor 24a is
While being embedded in the holding unit 43, the detection unit or the wiring process
Part inside the through hole 46 formed in the inward flange 45.
Have been entered. The holding portion 4 is attached to the inward flange 45.
3 is integrally molded with the fitting cylinder 42 in order to fix the same.
Means other than shape can also be used. For example, this hold
After molding the rotation speed sensor 24a in the part 43
Then, the mold is formed on the inner surface of the inward flange 45 in the axial direction.
Can be fixed by bonding or the like. Also, in the case of this example, molding by the above IC
Output signal that is output as a
Harness 30 for holding
One end surface in the circumferential direction of the sensor holder 34 (right end in FIG. 2)
Surface) and taken out of the holding portion 43. The sensor holder 34 configured as described above is
The fitting cylinder 42 is fitted to the inner end of the outer race 1 by interference fitting.
The outer ring is fixed concentrically with the inner ring 3. In addition,
The outer side surface in the axial direction of the inward flange portion 45 constituting the
The outer ring 1 is in contact with the inner end face. As mentioned earlier,
The inner end of the outer ring 1 is about 1 mm larger than the inner end face of the inner ring 3
Projecting inward in the axial direction;
Inner diameter d of 5₄₅Is the outer diameter D of the inner end of the inner ring 3_Three Less than
And make it smaller. Therefore, the outer diameter of the inner end face of the inner ring 3
The deviated portion and the inner diameter of the axially outer surface of the inward flange 45.
And a small gap 47 having a thickness of about 1 mm
As a result, they oppose each other over the entire circumference. And this small gap
47 constitutes a labyrinth seal. In addition, this
The thickness of the minute gap 47 depends on the elastic deformation of each part during use.
(1 mm or more)
Is preferable. In this state,
Detecting section of rotation speed sensor 24a and encoder main body 36
And a part in the circumferential direction of the inner surface in the axial direction of
Facing each other. Further, in the case of this embodiment, the sensor holder
34 of the inward flange 45 constituting the fitting cylinder 42 in the circumferential direction.
A discharge hole 49 (FIG. 2) is provided at the lower end when used.
And the lower edge of the discharge hole 49 is connected to the outer ring 1.
Is located lower than the inner peripheral surface of the lower end of the. On the other hand, a rolling bearing unit with a rotation speed detecting device
When mounting the kit to the car, the center of the hub 2
Drive shaft 14 is inserted into hole 13 (spline engagement).
And a large diameter provided in the intermediate portion of the drive shaft 14.
Butting the outer surface of the part 48 against the inner end surface of the inner ring 3
Prevents the inner ring 3 from moving relative to the hub 2.
Stop. In the case of this example, the sensor holder 3
4, the thickness H of the main body portion,
Properly regulate the dimensions of each part, such as the amount of protrusion of the inner end of the outer ring 1
By doing so, even in such an assembled state to the car,
Constant velocity joint housing provided at the inner end of the drive shaft 14
The shoulder of the jing 15 and the sensor holder 34 interfere with each other.
To prevent As described above, the rotation with the rotation speed detecting device of the present invention
In the case of a ball bearing unit, the outer diameter of the inner end face of the inner ring 3
Inside the fitting cylinder 42 of the sensor holder 34
The part close to the inner diameter of the axial outer surface of the facing flange 45 is
Over a minute gap 4 with a thickness (width) of 1 mm or less
7 and the small gap 47
It constitutes a virinth seal. For this reason, the completion of the car
Inside the hub 2, including during transportation to the assembly line of the product manufacturer
Even before the drive shaft 14 is inserted through the mandrel 13,
Axial inner surface of coder body 36 and rotational speed sensor 24a
At the inner side of the sensor holder 34,
Foreign matter such as magnetic powder enters from outside through the space
Can be prevented. Therefore, the reliability of wheel speed detection
Can be improved. In the case of this embodiment, the sensor holder 3
And a part of the inward flange 45 constituting the fitting cylinder 42
A discharge hole 49 is formed in a portion located at the lower end sometimes.
The lower edge of the discharge hole 49 is connected to the inner periphery of the outer race 1.
It is located below the lower end of the surface. Therefore,
First, between the inner end surface of the inner ring 3 and the inner surface of the inward flange 45.
The encoder 33 through the minute gap 47 formed in
If a foreign substance, such as rainwater, enters the installed space.
Even in this case, the fluid flowing down by the action of gravity in this space
Can be discharged to the outside through the discharge hole 49. Further, in the case of this embodiment, the sensor holder 34
On the axially inner surface of the inward flange 45 constituting the fitting cylinder 42 of FIG.
The holding portion 43 is connected and fixed, and the inward flange portion 45 is
Detection of the rotational speed sensor 24a inside the formed through hole 46
Section or wiring processing section. For this reason,
The axially outer side surface of the inward flange portion 45 constituting the joint tube 42 (see FIG.
The holding portion 43 is attached to the fitting cylinder 42
In a state of being provided inside the fitting tubular portion 44 constituting
Than the case, the main body of the sensor holder 34
The amount of protrusion from the inner end surface of the wheel 1
(The same as the thickness H). That is, the holding unit 4
3, the rotation speed sensor 24a and the rotation speed sensor 24
To embed the end of the harness 30 connected to a
The thickness of at least a part of the holding portion 43 is equal to or more than a predetermined size.
Need to be Moreover, the axial direction of the inward flange 45
When connecting the holding portion 43 to the outer side surface,
From the inner end surface of the outer ring 1 at the portion where the holder 34 is installed
The protrusion amount of the inward flange portion 4 corresponds to the thickness H of the holding portion 43.
5 or more (≧ H + T). this
On the other hand, in the case of this example,
The holding portion 43 is fixedly connected to the side surface, and
The rotation speed sensor is provided inside a through hole 46 formed in the flange 45.
A part of the support 24a is entered. For this reason, the above sensor
Projection of the main body of the holder 34 from the inner end surface of the outer ring 1
The amount is only the thickness H of the main body. Therefore,
The holding portion 43 is connected to the axially outer surface of the inward flange portion 45.
Than the thickness of the main body of the sensor holder 34
H can be reduced by the thickness T of the inward flange 45. this
As a result, the sensor holder 34 and the constant velocity joint
Interference with the housing 15 can be easily prevented. In the case of this embodiment, the rotational speed sensor
The harness 30 connected to the holding portion 43a is
Of the surfaces, from the circumferential end surface of the sensor holder 34,
It is taken out of the holding portion 43. Therefore, this hold
The harness 30 derived from the part 43 is
To prevent it from approaching the housing 15 and the drive shaft 14.
The harness 30 and these parts 15 and 14 interfere with each other.
Can be prevented. Next, FIGS. 4 and 5 show an embodiment of the present invention.
A second example is shown. In the case of this example, the first example described above
Unlike the case of, the inner end of the hub 2 is
And project inward in the axial direction. And this protrusion
Plastic deformation of the exposed part radially outward over the entire circumference
As a result, a caulked portion 50 is formed at the inner end of the hub 2.
I have. The caulking part 50 allows the inner ring 3
The inner ring 3 comes off from the hub 2 by holding down the inner end face.
Is prevented from doing so. In particular, in the case of this embodiment, the sensor holder 34
The inner peripheral edge of the inward flange 45 constituting the fitting cylinder 42 of FIG.
An elastic material 51 made of an elastomer such as
Are connected. Then, the inner ring 3
The elastic material 5 is provided at a portion outside the outer diameter side from the tightening portion 50.
The inner peripheral edge of the roller 1 is slid over the entire circumference. In the case of this example configured as described above,
Axially inner side of the encoder 33 than in the case of the first example
Foreign matter on the part between the surface and the detection part of the rotation speed sensor 24a
Can be more reliably prevented. Other configurations and works
Since the operation is the same as the case of the first example described above,
Equivalent parts are denoted by the same reference numerals, and duplicate description is omitted.
You. In each of the above examples, the encoder
33, an S pole and an N pole
Encoder body 3 in which are arranged alternately in the circumferential direction
6 is used. However, the present invention
It is limited to the structure using the encoder 33 like
There is no. For example, magnetic metal such as carbon steel sheet such as SPCC
At the circumferentially equal position of the plate material
Encoder book with a number of notches or through holes
Use an encoder that connects the body to the axially inner surface of the support ring.
Can also be used. In addition, use such an encoder
In this case, the rotation speed sensor facing this encoder
For example, a permanent magnet, pole piece, and coil
Use the one you obtained. It consists of an encoder and a sensor.
The structure of the rotation speed detection device uses a magnetic sensor.
Not limited to those using sensors such as eddy current type and photoelectric type
Are also an object of the present invention. However, permanent as encoder
For those using a magnet, the magnetic material remains attached
Therefore, it is important to apply the present invention.
No. In each of the above examples, the hub 2
Although the first inner raceway 7 is directly formed on the outer peripheral surface of the intermediate portion,
The present invention is not limited to such a structure. example
For example, the cylindrical surface formed on the outer peripheral surface of the intermediate portion of the hub 2
A separate inner ring with the first inner ring raceway formed on the peripheral surface
The present invention can be implemented with a fixed structure. [0037] The rolling bearing with the rotation speed detecting device of the present invention.
The units are configured and function as described above,
Before inserting the drive shaft into the center hole of the inner ring equivalent member
Also, the detection part of the rotation speed sensor and the detected part of the encoder
Foreign matter can be prevented from entering the space between
The reliability of the rotation speed detection can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1A shows a first example of an embodiment of the present invention, and FIG.
-OOB sectional drawing. FIG. 2 is a view seen from the right side of FIG. 1; FIG. 3 is an enlarged sectional view of part C of FIG. FIG. 4 is a view similar to FIG. 1, showing a second example of the embodiment of the present invention. FIG. 5 is an enlarged sectional view of a part D in FIG. 4; FIG. 6 is a cross-sectional view taken along the line EOE of FIG. 7, showing an example of a conventional structure. FIG. 7 is a view seen from the right side of FIG. 6; [Description of Signs] 1 Outer ring 2 Hub 3 Inner ring 4 First flange 5 Outer ring track 6 Second flange 7 First inner ring track 8 Small diameter step 9 Second inner ring track 10 Rolling element 11 First seal ring 12 Cylindrical space 13 Center hole 14 Drive shaft 15 Constant velocity joint housing 16 Assembly seal 17 Rotation side seal ring 18 Fixed side seal ring 19a, 19b Cores 20a, 20b Elastic material 21 Encoder 22 Notch 23 Cover 24, 24a Rotation speed Sensor 25 Synthetic resin 26 Holding part 27 Micro gap 28 Permanent magnet 29 Magnetic detection element 30 Harness 31 Harness take-out part 32 Second seal ring 33 Encoder 34 Sensor holder 35 Support ring 36 Encoder body 37 Ring part 38 Seal ring 39 Core 40 elastic members 41a, 41b, 41c seal lip 42 fitting cylinder 43 Holding part 44 Fitting cylinder part 45 Inward flange part 46 Through hole 47 Micro gap 48 Large diameter part 49 Discharge hole 50 Caulking part 51 Elastic material

Continuation of front page    F term (reference) 3D046 BB28 BB29 HH36                 3J101 AA02 AA43 AA54 AA62 FA23                       GA03

Claims (1)

Claims: 1. An outer ring which has a first flange for attaching to a suspension device on an outer peripheral surface, and an outer ring raceway on an inner peripheral surface, and which does not rotate during use, and an outer peripheral surface of the outer peripheral surface. An inner ring which has a second flange for supporting the wheel at the end portion, and an inner ring track which is also opposed to the outer ring track at the middle portion, and which is rotated during use by a drive shaft inserted through the center hole. A corresponding member, a plurality of rolling elements rotatably provided between the outer raceway and the inner raceway, and a portion of the inner race corresponding member which is outside the inner raceway on the outer peripheral surface at the inner end. An encoder supported concentrically with the corresponding member and having alternately and equally spaced circumferential characteristics of a detected portion, and a sensor holder fixed to a portion facing the encoder at the inner end of the outer ring. And this sensor holder Then, in a rolling bearing unit with a rotation speed detecting device provided with a rotation speed sensor having a detection portion opposed to a detection portion of the encoder, an inner end surface of the member corresponding to the inner ring is provided with one of the sensor holders. A rolling bearing unit with a rotation speed detecting device, wherein a part or a part of another member supported by the sensor holder is brought into close proximity or sliding contact over the entire circumference.