JPH11248726A - Rolling bearing unit with rotation speed detecting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To omit quenching treatment and to facilitate the working operation of an installing hole by not quenching and hardening a part where the installing hole is to be formed and making the thickness of a quenched and hardened layer be a predetermined value or more in a bearing unit in which the distance between the end edge of an outer ring raceway and the installing hole is a predetermined value. SOLUTION: Either of the parts of outer ring raceways 12 and 12 in which the distance between the end edge of the outer ring raceway 12 close to an installing hole 17 and the installing hole 17 lies in the range of 2-10.5 mm is subjected. Furthermore, for securing a minimum distance of 0.5 mm or more between quenched and hardened layers 24 and 24 formed in the parts of the ring raceways 12 and 12 and the installing hole 17, the thickness of the quenched and hardened layers 24 and 24 is regulated, and the part of the installing hole 17 remains as an unquenched and unhardened raw steel product or a partially row steel product in a soft state. By this, without complicating the quenching treatment of the quenched and hardened layers 24 and 24, it is possible to facilitate the working operation of the installing hole 17 for supporting a sensor 18 at an outer ring 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A rolling bearing unit with a rotation speed detecting device according to the present invention rotatably supports a wheel of an automobile with respect to a suspension device, and is used for detecting the rotation speed of the wheel.

[0002]

2. Description of the Related Art Rolling bearing units are used to rotatably support the wheels of an automobile with respect to a suspension system.
Further, in order to control an antilock brake system (ABS) or a traction control system (TCS), it is necessary to detect the rotation speed of the wheel. For this reason, the above-mentioned wheel is rotatably supported with respect to the suspension device by a rolling bearing unit with a rotation speed detecting device in which a rotation speed detecting device is incorporated in the above-mentioned rolling bearing unit, and the rotation speed of the wheel is detected. However, it has been widely practiced in recent years.

[0003] In such a rolling bearing unit with a rotation speed detecting device, a hub is rotatably supported on the inner diameter side of an outer ring via a plurality of rolling elements. At the same time, the rotational speed of the encoder fixed to a part of the hub and having its characteristics in the circumferential direction alternately and equally spaced can be detected by a sensor supported on a part of the outer ring. In a state where the sensor is supported in an axially intermediate portion of the outer ring in a mounting hole formed in a diameter direction of the outer ring, a detection portion of the sensor is attached to an outer peripheral surface of a large-diameter cylindrical portion of the encoder. For example, JP-A-63-59769, JP-A-6-109027, and 8-27065.
As described in many publications such as No. 9 and the like, it has been widely known.

When the above-described rolling bearing unit with a rotation speed detecting device is used, the outer ring is supported by a suspension device, and a wheel is fixed to a portion of the hub that is separated from the outer ring at one end of the hub. It is rotatably supported with respect to the suspension device. When the encoder rotates with the rotation of the wheel, the output of a sensor whose detection unit is opposed to the encoder changes. The frequency at which the output of this sensor changes is proportional to the rotational speed of the wheel. Therefore, if the output signal of this sensor is sent to a controller that determines the rotational speed of the wheel, ABS and TCS can be controlled appropriately.

[0005]

In the case of the rolling bearing unit with a rotation speed detecting device described in each of the above publications, consideration is not given to both the securing of the durability of the outer ring and the ease of machining the mounting hole. Was. That is, the surface of the double-row outer raceway formed on the inner peripheral surface of the outer raceway and a portion near this surface are provided with a quenched hardened layer having a hardness of, for example, Hv 500 or more for the purpose of ensuring the rolling fatigue life of each of the outer raceways. The depth at which the shearing force based on the stress applied from the rolling element is maximized (about 0.5 mm for a rolling bearing unit for an automobile)
It must be formed to a depth of at least twice (also about 1.5 mm). The thickness between the deepest part of the hardened hardened layer and the unhardened, so-called raw part is 0.5 mm.
There is a degree of transition layer. In the transition layer portion, the hardness gradually decreases from the hardened hardened layer to the green portion.

Conventionally, in order to form a quench hardened layer at each outer ring raceway portion as described above, the range of forming the quenched layer is limited to the outer ring even if the quenching depth is controlled in the thickness direction. No consideration has been given to the restriction in the surface direction (especially in the axial direction) of the inner peripheral surface. That is, in the thickness direction, in order to secure the toughness of the outer ring, it may be considered to leave a raw portion near the outer periphery of the outer ring (for example, see Japanese Utility Model Registration No. 2529597). No particular consideration was given to the plane direction. In this way, considering the range of the quench hardened layer only in the thickness direction and without considering the plane direction, if the quench hardened layer is formed on each of the outer raceway portions, the range of the quench hardened layer becomes In some cases, the outer raceway may reach about 10 mm or more from the end of the outer raceway. Then, the hardness is increased up to a portion about 10.5 mm or more away from the edge of each of the outer raceways including the transition layer.

On the other hand, in response to recent demands for fuel saving of automobiles, in order to reduce the size and weight of a rolling bearing unit for supporting wheels, it is necessary to reduce the axial dimension of the rolling bearing unit. Is underway. Due to such shortening, the distance between the edge of each outer raceway provided on the inner peripheral surface of the outer race and the mounting hole is shortened, and this distance may not be secured to 10.5 mm or more. For this reason, the hardness of the portion where the mounting hole is to be formed increases, and the processing of the mounting hole becomes troublesome. Processing of this mounting hole may be performed before forming a hardened hardened layer on each of the outer ring raceway portions,
When quenching and hardening treatment is performed after the mounting hole is processed, it is necessary to take care to prevent the occurrence of defects due to thermal stress concentration or the like in the mounting hole portion. .

Further, even when an impact load is applied to the outer ring via the hub and the rolling element due to the wheel hitting a curb or the like, the outer ring is less likely to be plastically deformed. In order to improve the durability of the rolling bearing unit, it is necessary to form a quenched and hardened layer between double-row outer ring raceways.
As described in Japanese Patent Publication No. 97, it is conventionally known. In this way, when the hardened layer is formed also between the double-row outer ring raceways, not only the small rolling bearing unit but also the edge of each outer ring raceway provided on the inner peripheral surface of the outer ring is attached. Even in the case of a relatively large rolling bearing unit with a rotation speed detecting device having a large distance from the hole, machining of the mounting hole becomes troublesome. In view of the above-described circumstances, the present invention has been made to realize a rolling bearing unit with a rotation speed detection device that can facilitate the work of machining the mounting hole without particularly complicating the quenching process. is there.

[0009]

All of the rolling bearing units with a rotation speed detecting device of the present invention have double rows of inner ring raceways on the outer peripheral surface, similarly to a conventionally known rolling bearing unit with a rotation speed detecting device. A hub that rotates with the wheel during use, an outer ring that has a double-row outer raceway at a position facing the double-row inner raceway on the inner peripheral surface, and is supported by the suspension device during use and does not rotate, A plurality of rolling elements provided between each of the inner raceways and each of the outer raceways so as to be freely rotatable, and externally fitted and fixed to a portion between the double-row inner raceways on an intermediate portion outer peripheral surface of the hub; An encoder in which the characteristics in the circumferential direction are alternately changed at equal intervals; and a detector, wherein the detector is opposed to the encoder and provided in a mounting hole provided at an axially intermediate portion of the outer ring. To change the characteristics of the encoder. And a sensor for changing an output signal in response. Then, a hardened hardened layer is formed on each of the outer raceway portions on the inner peripheral surface of the outer race.

[0010] In particular, in the rolling bearing unit with the rotation speed detecting device according to the first aspect, the distance between the end of the outer ring raceway close to the mounting hole and the mounting hole in the double row outer raceway is 10. The target is 5mm or less. In the rolling bearing unit with the rotation speed detecting device according to the first aspect, the portion where the mounting hole is formed is not hardened and hardened, and is formed on the outer ring raceway portion close to the mounting hole. The thickness of the hardened hardened layer is 1.5 mm or more. Further, in the rolling bearing unit with a rotation speed detecting device according to claim 2, the distance between the edge of the outer ring raceway close to the mounting hole and the mounting hole in the double row outer raceway is 2 mm.
最小 10.5 mm, and the minimum distance between the hardening layer formed on each outer raceway portion and having a hardness of Hv500 or more and the mounting hole is 0.5 mm or more. or,
4. The rolling bearing unit with a rotation speed detecting device according to claim 3, wherein the hardened hardened layers provided on the double row outer ring raceway portions are provided at positions circumferentially deviated from the mounting holes. Continuous with each other by the cured layer,
In addition, the portion where the mounting hole is formed is not quenched and hardened. Further, in the rolling bearing unit with a rotation speed detecting device according to claim 4, the hardened hardened layers provided on the double row outer ring raceway portions are provided at positions circumferentially deviated from the mounting holes. Further, they are connected to each other by a connection hardened layer having a hardness of Hv 500 or more, and the minimum distance between the connection hardened layer and the mounting hole is 0.5 mm or more.

[0011]

With the rolling bearing unit with the rotation speed detecting device of the present invention configured as described above, the wheel is rotatably supported with respect to the suspension device, and the operation at the time of detecting the rotation speed of the wheel is the same as the conventional one. This is the same as the case of a rolling bearing unit with a rotation speed detecting device generally known from U.S. Pat.

In particular, in the rolling bearing unit with a rotation speed detecting device according to the first and second aspects of the rolling bearing unit with a rotation speed detecting device of the present invention, the hardening process of each outer ring raceway portion is troublesome. In addition, the working of mounting holes for supporting the sensor on the outer ring can be facilitated without deteriorating the durability of each outer ring raceway portion. That is, the mounting holes are not hardened and hardened, so that the mounting holes can be easily processed.

For example, in the case of the rolling bearing unit with the rotation speed detecting device according to the second aspect, the distance between the end of the outer raceway close to the mounting hole and the mounting hole is set to 2 mm or more. The minimum thickness (1.5 mm) of the hardened and hardened layer required for securing the durability of the track can be secured. or,
By setting the minimum distance between the hardened hardened layer formed on each of the outer ring raceway portions and the mounting hole to 0.5 mm or more, the mounting hole portion is a raw portion that is also separated from the transition layer, or at least has a hardness of at least one. The mounting hole can be easily processed even after a hardened layer is formed on each of the outer raceway portions because it is formed as a low semi-life portion.

Further, according to the rolling bearing unit with the rotation speed detecting device according to the third and fourth aspects, even when an impact load is applied to the outer ring via the hub and the rolling element, the outer ring is less likely to be plastically deformed. Moreover, the mounting holes can be easily processed.

[0015]

1 to 3 show a first embodiment of the present invention corresponding to claims 1 and 2. FIG. The rolling bearing unit that constitutes the rolling bearing unit with the rotation speed detecting device of the present embodiment includes a hub 3 formed by combining a hub body 1 and an inner ring 2, an outer ring 4, and a plurality of rolling elements 5,5. Of these, the outer end portion of the outer peripheral surface of the hub body 1 (the outside refers to the side that is outward in the width direction when assembled to an automobile, and is the left side in FIGS. 1 and 2; Is called the inner side, and is the right side in FIGS.
A flange 6 for supporting the wheel is provided. An inner raceway 7 is formed on the outer peripheral surface of the intermediate portion of the hub body 1. The inner ring raceway 7 may be formed directly on the outer peripheral surface of the intermediate portion of the hub main body 1 or may be formed on the outer peripheral surface of a separate inner ring externally fitted on the outer peripheral surface of the intermediate portion of the hub main body 1 in some cases.

A stepped portion 8 which is recessed diametrically inward from the outer peripheral surface of the hub body 1 is provided at the inner end of the hub body 1.
Is provided concentrically with the hub body 1 over the entire circumference. The inner ring 2 having another inner ring track 7 formed on the outer peripheral surface is externally fixed to the step 8 by interference fitting.
In this state, the inner end of the inner race 2 projects axially inward from the inner end surface of the hub body 1 in the state where the outer ring is fixed. The inner end surface of the inner ring 2 is assembled to a vehicle,
It comes into contact with a step surface of a constant velocity joint (not shown). Also, in a state of being assembled to the vehicle, a spline shaft attached to the constant velocity joint is inserted into a spline hole 9 provided in the center of the hub body 1. Then, a nut (not shown) is screwed into a male screw portion provided at a tip of the spline shaft at a portion protruding outward from the outer end surface of the hub main body 1, and further tightened. On the basis of the tightening of the nut, the step surface of the constant velocity joint strongly presses the inner end surface of the inner ring 2 to prevent the inner ring 2 from coming out of the step 8. Of the intermediate portion of the hub body 1 formed with a diameter larger than that of the step portion 8, a fitting portion having a diameter slightly smaller than the intermediate portion of the hub body 1 is fitted to the end portion on the side of the step portion 8. 10 are provided. The outer diameter of the fitting portion 10 is slightly larger than the inner diameter of the encoder 11 in a free state described later,
The encoder 11 can be externally fixed by an interference fit. The outer diameter of the encoder 11 is smaller than or equal to the outer diameter of a portion closer to the outside of the fitting portion 10 in the intermediate portion of the hub body 1 in a state where the encoder 11 is externally fitted and fixed to the fitting portion 10.

On the inner peripheral surface of the outer race 4, double-row outer races 12, opposed to the inner races 7, 7, respectively, are provided.
12 are formed. And, each of these inner ring raceways 7, 7
A plurality of rolling elements 5, 5 are provided between the outer ring raceways 12 and 12 so as to roll freely while being held by retainers 13, 13, respectively. 3 is rotatably supported. In the illustrated example, balls are used as the rolling elements 5 and 5. However, in the case of a heavy-weight rolling bearing unit for an automobile, tapered rollers may be used as these rolling elements. or,
An outer flange-like mounting portion 14 for mounting the outer ring 4 to a suspension device is provided on an outer peripheral surface of a portion near the inner end of the outer ring 4.
Is provided. Further, gaps between the openings at both ends of the outer ring 4 and the outer peripheral surface of the intermediate portion of the hub body 1 and the outer peripheral surface of the inner end of the inner ring 2 are closed by seal rings 15, 15, respectively.

Further, an encoder 11 is externally fitted and fixed to the fitting portion 10 at a part of the outer peripheral surface of the intermediate portion of the hub body 1 concentrically with the hub body 1. This encoder 11
The whole is formed in a cylindrical shape by a magnetic metal plate such as a steel plate, and is fixed to the fitting portion 10 by external fitting by means of interference fit, so that a portion between the rows of the rolling elements 5 and 5 provided in the double row is provided. Has been placed. Further, a plurality of through holes 16 are formed at an intermediate portion in the axial direction of the encoder 11 at equal intervals in the circumferential direction so that the magnetic characteristics of the outer peripheral surface of the encoder 11 can be changed in the circumferential direction. Are changed alternately and at equal intervals.

On the other hand, a mounting hole 17 is provided at an axially intermediate portion of the outer race 4 at a position radially outward of the encoder 11.
The inner peripheral surface and the outer peripheral surface of the outer ring 4 are formed so as to communicate with each other. A sensor 18 having a detection element embedded in a synthetic resin is inserted and fixed in the mounting hole 17, and a detection unit provided on a front end face (lower end face in FIG. 1) of the sensor 18 is connected to the encoder 11 is opposed to the outer peripheral surface via a minute gap. In this manner, the sensor 1 is
The sensor 18 can detect the rotation speed of the encoder 11 in a state where the encoder 8 is inserted and fixed.

The outer peripheral surface of the outer ring 4 is provided with the mounting holes 17.
A flat mounting surface 19 is formed around the outer end opening in a direction perpendicular to the central axis of the mounting hole 17. The mounting surface 19 and the mounting hole 17
A conical concave-shaped chamfered portion 20 and a cylindrical-shaped receiving surface 21 are formed in order from the mounting surface 19 side in a continuous portion with the inner peripheral surface. On the other hand, a mounting portion 22 is fixed to a base end portion (upper end portion in FIG. 1) of the sensor 18, and the mounting portion 22 is attached to the outer ring 4 by a screw (not shown) inserted into an end portion of the mounting portion 22. The connection is fixed. In this state, the O-ring 23 externally fitted to the base end of the sensor 18 is elastically compressed between the outer peripheral surface of the base end and the inner peripheral surface of the receiving surface 21 to thereby form the sensor 18. Seal the part with
Foreign matter such as rainwater is prevented from entering the outer race 4 through the mounting hole 17.

Further, quench hardened layers 24, 24 having a hardness of Hv 500 or more are formed on the outer ring raceways 12, 12 on the inner peripheral surface of the outer ring 4. Each of these hardened hardened layers 24, 24 has the above-mentioned outer raceway 1 regardless of the load repeatedly applied from the rolling surfaces of the rolling elements 5, 5.
To ensure the rolling fatigue life of 2,12 parts,
As described above, it has a thickness of 1.5 mm or more. In particular, the rolling bearing unit with a rotation speed detecting device according to the present invention includes the outer ring raceways 12, 12, the edge of the outer raceway 12 on the right side of FIGS. 17 whose distance L (FIG. 3) is within the range of 2 to 10.5 mm. Moreover, in the present invention, in particular, in the case of the rolling bearing unit with a rotation speed detecting device according to claims 1 and 2, the hardened hardened layers 24, 24 formed on the respective outer raceways 12, 12 and the mountings. Hole 17
In order to secure a minimum distance of 0.5 mm or more, the thickness T (FIG. 3) of each of the hardened hardened layers 24, 24 is regulated so that the mounting holes 17 are not hardened and hardened. Steel material, or it is in a soft state of half life.

When the distance L is less than 2 mm, the present invention is intended to secure the rolling fatigue life of the outer raceways 12 and 12 and to facilitate the machining of the mounting hole 17. However, the object of the invention described in claims 1 and 2 cannot be achieved. Further, when the distance L exceeds 10.5 mm, this is a feature of the invention described in claims 1 and 2.
The processing of the mounting hole 17 can be easily performed without restricting the thickness T of each of the hardened hardened layers 24, 24. In other words, in the case of a relatively large rolling bearing unit with a rotation speed detecting device such that the distance L exceeds 10.5 mm, the above-mentioned structure can be obtained without applying the inventions described in claims 1 to 2 in particular. Processing of the mounting hole 17 can be easily performed. Furthermore, the invention described in claims 1 and 2
Unless the thickness T of each of the hardened hard layers 24, 24 is regulated, processing of the mounting hole 17 becomes troublesome, and the rotation L is relatively small such that the distance L does not exceed 10.5 mm. It is intended for rolling bearing units with speed detectors.

In the case of the rolling bearing unit with the rotation speed detecting device according to the present invention described in claims 1 and 2, the wheel fixed to the flange 6 provided at the outer end of the hub body 1 is
The suspension device supporting the outer race 4 can be rotatably supported. When the encoder 11 externally fitted and fixed to the inner ring 2 rotates with the rotation of the wheel, the vicinity of the detection unit provided on the tip end surface of the sensor 18 is changed to the through hole 16 provided at the axially intermediate portion of the encoder 11. , 16 circumferentially adjacent to the through hole 1
The pillar portions existing between 6, 6 pass alternately.
As a result, the density of the magnetic flux flowing in the sensor 18 changes, and the output of the sensor 18 changes. The frequency at which the output of the sensor 18 changes in this way is proportional to the rotational speed of the wheel. Therefore, if the output of the sensor 18 is sent to a controller (not shown), the ABS and TCS can be appropriately controlled.

In particular, in the case of the rolling bearing unit with the rotation speed detecting device of the present invention, the quenching process of the hardened hardened layers 24 formed on the outer raceways 12, 12 is not complicated. The work of machining the mounting hole 17 for supporting the sensor 18 on the outer race 4 can be facilitated. That is, since the distance L between the end of the outer raceway 12 on the right side in FIGS. 12 can secure the minimum thickness (1.5 mm) of the hardened hardened layer 24 necessary for ensuring the durability. Needless to say, the minimum thickness (1.5 mm) of the hardened hard layer 24 required to secure the durability of the outer raceway 12 is also provided on the outer raceway 12 on the left side of FIGS. ) Can be secured. Also, by setting the minimum distance between the hardened hardened layers 24, 24 formed on the outer ring raceways 12, 12 and the mounting holes 17 to 0.5 mm or more, the mounting holes 17 can be moved from the transition layer. The attachment holes 17 can be easily processed even after the hardened layers 24, 24 are formed on the outer raceways 12, 12, which are formed in the raw portions having a low hardness. The thickness of the hardened hardened layers 24, 24 can be controlled relatively easily by regulating the amount of current applied to the quenched coil and the duration of the current.

Next, FIGS. 4 to 6 show a second example of the embodiment of the present invention corresponding to claims 3 and 4. FIG. In the case of this example, a double-row outer raceway 1 formed on the inner peripheral surface of the outer race 4
Hardened hardened layers 24, 2 provided on portions 2 and 12 respectively
The connection members 4 are connected to each other by a connection hardened layer 25 provided at a position deviated from the mounting hole 17 in the circumferential direction of the outer ring 4. In other words, on the inner peripheral surface of the outer race 4, the double-row outer raceways 12, and both outer raceways 12, 12
Except for the peripheral portion of the mounting hole 17, the hardened layers 24, 24 and the joint hardened layer 25 have
Hardened to 0 or more. In the case of this example, not only the minimum distance between each of the hardened hardened layers 24, 24 and the mounting hole 17 is set to 0.5 mm or more, but also the connection hardened layer 25, the mounting hole 15, Also has a minimum distance L ′ (FIG. 6) of 0.
5 mm or more. By doing so, the mounting hole 15 is left as a raw steel material that has not been quenched and hardened, or is in a soft state of about half life.

In the case of the present embodiment constructed as described above, a part of the outer race 4 between the double-row outer raceways 12, 12 is less likely to be plastically deformed. For this reason, even if an impact load is applied to the outer ring 4 via the hub 3 and the rolling elements 5 and 5 due to the wheel hitting a curb, the outer ring 4 is less likely to be plastically deformed. It is possible to improve the durability of the rolling bearing unit with the rotation speed detecting device including the rotation speed detecting device. Even in the case of the present example, the toughness of the outer ring 4 is ensured by leaving a raw portion that is not quenched and hardened around the joint hardened layer 25, and the impact load is applied to the outer ring 4. This prevents damage such as cracks from occurring.

The hardened hardened layers 24, 24 as in this embodiment
In order to form the connection hardened layer 25, as shown in FIG. 7, for example, a quenched coil 26 is used in which only the portion facing the inner diameter side opening of the mounting hole 17 is concave inward in the diameter direction. That is, the outer peripheral surface of the hardened coil 26 is
The inner peripheral surface shape of the mounting hole 17 is substantially similar to that of FIG. When the quenching coil 26 is energized in a state where such a quenching coil 26 is disposed inside the outer ring 4 and concentrically with the outer ring 4, the double-row outer ring raceway 12 is formed on the inner peripheral surface of the outer ring 4. , 12 and both outer raceways 12,
The portion between 12 is heated except for the peripheral portion of the mounting hole 17, and the heated portion can be quenched.
When only a predetermined portion of the inner peripheral surface of the outer ring 4 is quenched and hardened using the quenching coil 26 as described above,
In order to more strictly control the boundary between the hardened and hardened portion and the hardened and hardened portion, the hardening coil 26 is used.
It is conceivable to reduce the distance between the outer peripheral surface of the outer ring and the inner peripheral surface of the outer ring 4. In such a case, when the outer diameter of the convex portion present at both axial ends of the quenched coil 26 is larger than the inner diameter of the minimum diameter portion existing at the axial middle portion of the outer ring 4, The quenching coil 26 has a split structure that can be divided in the axial direction. In the case of this example, the edge of the outer raceway 12 near the mounting hole 17 and the mounting hole 17
Is not required to be 10.5 mm or less.
It may be 0.5 mm or less (however, 2 mm or more). Other configurations and operations are the same as in the case of the above-described first example.

As another method for realizing the structure of the second embodiment of the present invention shown in FIGS. 4 to 6, a hardening hardening layer 24, 24 of each outer raceway 12, 12 is connected with hardening hardening. The layers 25, 25 can also be formed in time. For example, after forming the respective connection hardened layers 25, 25 while the outer ring 4 is stationary, the respective hardened hard layers 24, 24 are formed while rotating the outer ring 4, and the respective hardened hard layers 24, 24 are formed. , 24 and the respective connection hardened layers 25, 2
It is conceivable to make 5 and 5 continuous. Or conversely, after forming each of these hardened hardened layers 24, 24, each of the above-described joint hardened layers 25, 25 can also be formed.

Next, FIG. 8 shows a third example of the embodiment of the present invention, which also corresponds to the third and fourth aspects. In the second example described above, the hardened hardened layers 25 provided on the double-row outer ring raceways 12 and 12 to connect the hardened hardened layers 24 and 24 to each other are provided over substantially the entire circumference except for the mounting holes 17. In contrast, in the case of the present example, it is provided intermittently at three positions in the circumferential direction. The mounting hole 17 is arranged in a portion between the connection hardened layers 25 adjacent to each other in the circumferential direction. Other configurations, operations, and manufacturing methods are the same as those of the above-described second example.

Next, FIGS.
9 shows a fourth example of the embodiment of the present invention corresponding to FIG. In the case of this example, the connection hardened layer 25 is intermittently provided at two circumferential positions on the inner peripheral surface of the outer ring 4. And
The mounting hole 17 is connected to the connection hardened layer 2 adjacent in the circumferential direction.
It is arranged in the portion between 5, 25. Other configurations, operations, and manufacturing methods are the same as those in the third example.

In the example shown, the drive wheels (FR vehicle and RR
Although the present invention has been described in the case where the present invention is applied to a rolling bearing unit for supporting a rear wheel of a vehicle, a front wheel of an FF vehicle, and all wheels of a 4WD vehicle, the present invention relates to a driven wheel (a front wheel of an FR vehicle and an RR vehicle). , F
The present invention can also be applied to a rolling bearing unit for supporting (rear wheel) of an F vehicle. In addition, the feature of the present invention is that even in the case of a small rolling bearing unit with a rotational speed detecting device having a small axial dimension, it is possible to easily perform an operation of forming a mounting hole for fixing a sensor support formed in an intermediate portion of an outer ring. Therefore, the range of the hardened hard layer formed on the inner peripheral surface of the outer ring is devised. The type of the rotation speed detecting device is not particularly limited. Therefore, the rotation speed detecting device is not limited to the magnetic detection type as shown in each of the examples shown in the drawings, but may be another type such as an eddy current type or a photoelectric type.

[0032]

Since the present invention is constructed and operates as described above, it is possible to reduce the cost by facilitating the working operation of the rolling bearing unit with the rotation speed detecting device. Further, if necessary, it is possible to cope with a reduction in size and weight of the rolling bearing unit with a rotation speed detecting device.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first example of an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing only an outer ring.

FIG. 3 is an enlarged view of a portion A in FIG. 2;

FIG. 4 is a sectional view showing a second example of the embodiment of the present invention.

FIG. 5 is a sectional view showing only an outer ring.

FIG. 6 is a sectional view taken along line BB of FIG. 5;

FIG. 7 is a sectional view showing a state in which a quenched coil is installed inside the outer ring.

FIG. 8 is a view similar to FIG. 6, showing a third example of the embodiment of the present invention.

FIG. 9 is a cross-sectional view of the outer race, showing the fourth example.

FIG. 10 is a sectional view taken along line CC of FIG. 9;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hub main body 2 Inner ring 3 Hub 4 Outer ring 5 Rolling element 6 Flange 7 Inner ring raceway 8 Step part 9 Spline hole 10 Fitting part 11 Encoder 12 Outer raceway 13 Cage 14 Mounting part 15 Seal ring 16 Through hole 17 Mounting hole 18 Sensor 19 Mounting surface 20 Chamfered portion 21 Receiving surface 22 Mounting portion 23 O-ring 24 Hardened hard layer 25 Joint hardened layer 26 Hardened coil 27 Concave portion

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G01P 3/488 G01P 3/488 L

Claims (4)

[Claims] 1. A hub having a plurality of rows of inner races on an outer peripheral surface thereof and rotating together with wheels when used, and a plurality of rows of outer races at a position facing the inner race of the double rows on the inner periphery. An outer ring made of a steel material that is supported by the suspension device during use and does not rotate; a plurality of rolling elements provided between the inner ring tracks and the outer ring tracks so as to be freely rolled; and an outer peripheral surface of an intermediate portion of the hub And an encoder in which the characteristics in the circumferential direction are alternately and equally changed at an equal interval, which are externally fitted and fixed to a portion between the inner raceways of the double row, and a detector. In a mounting hole provided at an intermediate portion in the axial direction of the outer ring in a state in which the output signal is changed in accordance with a change in the characteristics of the encoder. A hardened hardened layer is formed on the raceway, and the outer row of the double row A rolling bearing unit with a rotation speed detecting device, wherein a distance between an end of an outer raceway close to the mounting hole and the mounting hole is 10.5 mm or less, and a portion where the mounting hole is formed is hardened. Not cured,
A rolling bearing unit with a rotation speed detecting device, wherein a hardened hard layer formed on an outer raceway portion near the mounting hole has a thickness of 1.5 mm or more. 2. A hub having a plurality of rows of inner races on an outer peripheral surface thereof and rotating together with wheels when used, and a plurality of rows of outer races at a position facing the inner race of the double races on the inner periphery. An outer ring made of a steel material that is supported by the suspension device during use and does not rotate; a plurality of rolling elements provided between the inner ring tracks and the outer ring tracks so as to be freely rolled; and an outer peripheral surface of an intermediate portion of the hub And an encoder in which the characteristics in the circumferential direction are alternately and equally changed at an equal interval, which are externally fitted and fixed to a portion between the inner raceways of the double row, and a detector. In a mounting hole provided at an intermediate portion in the axial direction of the outer ring in a state in which the output signal is changed in accordance with a change in the characteristics of the encoder. Hardened layer with hardness of Hv500 or more is formed on the raceway And a speed sensing rolling bearing unit, of the outer ring raceway of the double row, the distance between the mounting hole and the edge of the outer ring raceway close to the mounting hole 2
Rolling with a rotation speed detector with a minimum distance of 0.5 mm or more between the quenched hardened layer having a hardness of not less than Hv500 formed in each outer ring raceway portion and the above-mentioned mounting hole within a range of 10.5 mm. Bearing unit. 3. A hub having a double-row inner raceway on the outer peripheral surface and rotating together with the wheel when in use, and a double-row outer raceway at a position facing the double-row inner raceway on the inner circumferential surface, An outer ring made of a steel material that is supported by the suspension device during use and does not rotate; a plurality of rolling elements provided between the inner ring tracks and the outer ring tracks so as to be freely rolled; and an outer peripheral surface of an intermediate portion of the hub And an encoder in which the characteristics in the circumferential direction are alternately and equally changed at an equal interval, which are externally fitted and fixed to a portion between the inner raceways of the double row, and a detector. In a mounting hole provided at an intermediate portion in the axial direction of the outer ring in a state in which the output signal is changed in accordance with a change in the characteristics of the encoder. A rotation speed detector with a quenched and hardened layer formed on the raceway Bearing unit, wherein the hardened hardened layers respectively provided in the double row outer ring raceway portion are continuous with each other by a joint hardened layer provided at a position deviated in a circumferential direction from the mounting hole, In addition, a rolling bearing unit with a rotation speed detecting device, in which a portion where the mounting hole is formed is not quenched and hardened. 4. A hub having a plurality of rows of inner races on an outer peripheral surface thereof and rotating together with wheels when used, and a plurality of rows of outer races at a position facing the inner race of the double rows on the inner periphery. An outer ring made of a steel material that is supported by the suspension device during use and does not rotate; a plurality of rolling elements provided between the inner ring tracks and the outer ring tracks so as to be freely rolled; and an outer peripheral surface of an intermediate portion of the hub And an encoder in which the characteristics in the circumferential direction are alternately and equally changed at an equal interval, which are externally fitted and fixed to a portion between the inner raceways of the double row, and a detector. In a mounting hole provided at an intermediate portion in the axial direction of the outer ring in a state in which the output signal is changed in accordance with a change in the characteristics of the encoder. Hardened layer with hardness of Hv500 or more is formed on the raceway A rolling bearing unit with a rotation speed detecting device, wherein the hardened hardened layers provided on the outer raceway portions of the double row are provided at positions circumferentially deviated from the mounting holes, and have a hardness of Hv500. A rolling bearing unit with a rotation speed detection device, wherein the rolling connection unit is continuous with the connection hardened layer as described above, and the minimum distance between the connection hardened layer and the mounting hole is 0.5 mm or more.