JP2012173205A - Pulsar ring and rolling bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the breakage of a magnetized body due to difference of the heat deforming amount between the magnetized body and a fixing member.SOLUTION: A pulsar ring 20 comprises a fixing member 11 which is made from a metallic material, and has a cylindrical portion 11a and an annular ring portion 11c extending outward in a radial direction from an end portion on one side in an axial direction of the cylindrical portion 11a; and a magnetized body 15 which is made from a synthetic resin material in which a magnetic material is mixed, and attached to a side surface of the ring portion 11c. On the side surface of the ring portion 11c, a hole 21 is formed. On the magnetized body 15, a projecting portion 16 which is inserted in the hole 21 to couple the ring portion 11c and the magnetized body 15 is formed. Between an inner surface of the hole 21 and an outer surface of the projecting portion 16, a deformation absorbing body 30 for absorbing difference of the heat deforming amount between the magnetized body 15 and the ring portion 11c is provided.

Description

  The present invention relates to a pulsar ring that constitutes a sensor device for detecting the rotational speed (number of rotations) of a wheel or the like, and a rolling bearing device including the pulsar ring.

  A vehicle such as an automobile equipped with an antilock brake system (ABS) or a traction control system (TCS) is provided with a sensor device for detecting the rotational speed of wheels. As this sensor device, a device provided with a pulsar ring provided on the inner ring side (rotation side) of a hub unit for attaching wheels to a vehicle and a magnetic sensor provided on the outer ring side (fixed side) is known. (For example, refer to Patent Document 1).

  The pulsar ring of the sensor device is composed of an annular fixing member and a magnetized body bonded to the fixing member. The fixing member has a cylindrical portion that is fitted to the outer peripheral surface of the inner ring and an annular portion that is bent and extends radially outward from the axially outer end portion of the cylindrical portion, and has a substantially L-shaped cross section. A magnetized body is attached to the outer surface in the axial direction of the annular portion.

JP 2002-340921 A

Generally, the fixing member of the pulsar ring is made of a metal material, and the magnetized body is made of rubber or hard resin containing the magnetic material. In addition, when the magnetized body is formed of a hard resin, an adhesive is used to bond the magnetized body to the fixing member.
However, when the magnetized body is bonded to the fixing member with an adhesive, a small amount of oil remains on the bonding surface of the both, or the release agent contained in the magnetized body bleeds out, thereby bonding with the adhesive. There is a disadvantage that the strength is lowered. In addition, the adhesive also has a drawback that the adhesive strength tends to be uneven depending on the bonding location. Therefore, it is desired to attach the magnetized body to the fixing member without using an adhesive.

  In the pulsar ring described in Patent Document 1, the magnetized body is made of rubber, a protrusion is formed on the back surface of the magnetized body, a through hole is formed in the fixing member, and the protrusion is elastically formed in the through hole. The magnetized body is attached to the fixed member by press-fitting. And even when the magnetized body is made of a synthetic resin, it is considered that the magnetized body can be attached to the fixing member without using an adhesive by using the projection and the through hole as described above. It is done.

  However, since the coefficient of thermal expansion is different between the synthetic resin magnetized body and the metal fixing member, the difference in thermal deformation between the magnetized body and the fixing member when the pulsar ring is used in an environment where the temperature changes rapidly. Due to (difference in thermal expansion and difference in thermal contraction), a large stress is generated around the protrusion inserted into the through hole, and the possibility of cracking in the magnetized body starting from the root of the protrusion is increased.

  The present invention has been made in view of the above-described problems, and in the case where the magnetic body is fixed to the fixed member by inserting the protrusion formed on the magnetic body into the hole formed in the fixed member, the magnetic body is fixed to the fixed member. It is an object of the present invention to provide a pulsar ring capable of preventing a magnetized body from being damaged due to a difference in thermal deformation amount with respect to a member, and a rolling bearing device including the pulsar ring.

The pulsar ring according to the present invention is:
It is made of a metal material, and is composed of a cylindrical member and a fixing member having an annular ring portion extending radially outward from one axial end of the cylindrical portion, and a synthetic resin material mixed with a magnetic material, A pulsar ring provided with a magnetized body attached to an axial side surface of the annular portion,
A hole is formed in the side surface of the annular portion,
The magnetic body is formed with a protrusion that connects the fixing member and the magnetic body by being inserted into the hole,
A deformation absorber is provided between the inner surface of the hole and the outer surface of the protrusion to absorb a difference in thermal deformation between the magnetized body and the annular portion.

  According to this configuration, even if the magnetized body and the fixing member are deformed by different amounts of thermal deformation by using the pulsar ring in an environment where the temperature change is severe, the projecting portion and the hole, which are the connecting portions of both, The difference in the amount of thermal deformation is absorbed by the deformation absorber provided between the two. For this reason, it is possible to suppress stress concentration around the protrusion, and to prevent the magnetized body from being damaged.

The deformation absorber can be formed of a polymer material having a smaller elastic modulus than the magnetized body. Thereby, the difference in deformation amount between the magnetized body and the fixing member can be appropriately absorbed.
Further, the deformation absorber is disposed along the side surface of the annular portion extending from the cylindrical portion disposed along the inner surface of the hole and radially outward from one axial end of the tubular portion. It can consist of a buttock. With such a configuration, the protrusion is covered with the deformation absorber in a range including the root portion, and damage to the magnetized body starting from the root portion of the protrusion can be more reliably prevented. .

  The hole may be formed through the annular portion in the axial direction, and the protrusion may protrude from a side surface of the annular portion opposite to the side surface. With such a configuration, it is difficult for the protrusion to be detached from the hole, and it is possible to prevent the magnetized body from being detached from the fixing member.

It is preferable that a plurality of the holes and the protrusions are provided at intervals in the circumferential direction with respect to the annular portion and the magnetized body, respectively.
With such a configuration, it is possible to make it difficult for the magnetized body to fall off the fixing member over the entire circumferential direction.

The rolling bearing device according to the present invention is
Inner ring,
An outer ring disposed radially outward of the inner ring;
A plurality of rolling elements provided between the inner ring and the outer ring so as to be capable of rolling;
And the above-described pulsar ring attached to the outer peripheral surface of the inner ring.

  According to the present invention, it is possible to suppress stress concentration around the protrusions inserted into the holes formed in the fixing member due to the difference in thermal deformation between the fixing member and the magnetized body, Thereby, damage to the magnetized body can be prevented.

It is sectional drawing which shows the rolling bearing apparatus provided with the pulsar ring which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows a pulsar ring. It is sectional drawing which expands and shows a part of pulsar ring.

Hereinafter, embodiments of the pulsar ring and rolling bearing device of the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view showing a rolling bearing device 1 provided with a pulsar ring according to the first embodiment of the present invention. FIG. 2 is a cross-sectional view showing the pulsar ring in FIG. In addition, the left-right direction in these figures is called an axial direction, and the up-down direction is called radial direction. Further, with respect to the axial direction, the side (or direction) heading from the inside to the outside of the rolling bearing device 1 is referred to as the axially outer side (or axially outward), and the side (or direction) from the outside to the inside of the rolling bearing device 1. Is referred to as the axially inner side (or axially inner side).

  As shown in FIG. 1, the rolling bearing device 1 includes an inner ring 9 to which a vehicle wheel is attached, an outer ring 3 provided radially outward of the inner ring 9, and an inner ring 9 and an outer ring 3. The double row rolling elements 4 and 5 provided are provided.

  The inner ring 9 includes an inner shaft 2 and an inner ring constituting member 6, and the inner shaft 2 has a flange 2 c for attaching a wheel side member (not shown) to an end portion on the vehicle outer side (left side in FIG. 1). ing. A small-diameter portion 2d is formed on the vehicle inner side (right side in FIG. 1) of the inner shaft 2, and an inner ring constituting member 6 is fitted on the small-diameter portion 2d. The inner ring constituent member 6 has an inner track 6a for the rolling element 5 on the vehicle inner side formed on the outer peripheral surface thereof. Further, an inner track 2a for the rolling element 4 on the vehicle outer side is formed in the middle diameter portion 2e of the axially intermediate portion of the inner shaft 2. Further, the inner shaft 2 has a caulking portion 2f that is bent outwardly in the radial direction at the end on the vehicle inner side, and the inner ring constituting member 6 is connected to the inner shaft 2 by the caulking portion 2f. It is fixed against falling.

  The outer ring 3 is provided coaxially with the inner ring 9 via double-row rolling elements 4 and 5. On the inner circumferential surface of the outer ring 3, outer raceways 3a for double row rolling elements 4 and 5 are formed. Further, a flange 3c is formed on the outer peripheral surface of the outer ring 3, and the rolling bearing device 1 is fixed to the vehicle body side member by attaching the flange 3c to a vehicle body side member (not shown). Therefore, the outer ring 3 is a fixed side, and the inner ring 9 is a rotating side (rotating member) that rotates about the axis. And in order to seal the annular space R between the inner ring | wheel 9 and the outer ring | wheel 3, the cyclic | annular sealing apparatus 7 is provided in the axial direction both ends.

  A sealing device 7 shown in FIG. 2 can be used as a sealing device on the vehicle inner side (right side) of FIG. The sealing device 7 is provided between the inner peripheral surface 3b of the outer ring 3 and the outer peripheral surface 6b of the inner ring constituting member 6, and leakage of lubricant from the inside of the rolling bearing device 1 on the rolling elements 4 and 5 side. Intrusion of foreign matter such as muddy water from the outside of the rolling bearing device 1 to the rolling elements 4 and 5 is prevented.

The sealing device 7 includes a seal member 10 fixed to the outer ring 3 and a slinger 11 fixed to the inner ring constituting member 6.
The seal member 10 includes a metal core 12 and a seal portion 13. The metal core 12 includes a cylindrical portion 12a that is fitted in the outer ring 3, and an annular portion 12c that is bent and extends radially inward from an end portion 12b on the inner side in the axial direction (left side in FIG. 2) of the cylindrical portion 12a. And has a substantially L-shaped cross section. The core metal 12 has an annular shape as a whole, and is formed by, for example, pressing a cold-rolled steel plate such as SPCC, SPCD, SPCE or the like. A seal portion 13 made of an elastic body such as rubber is integrated with the core metal 12 mainly on the outer peripheral surface of the cylindrical portion 12a of the core metal 12 and the side surface on the axially outer side (right side in FIG. 2) of the annular portion 12c. It is fixed to become.

  The slinger 11 extends from a cylindrical cylindrical portion 11a fitted on the outer peripheral surface 6b of the inner ring constituent member 6 and an axially outer end portion 11b of the cylindrical portion 11a that is bent substantially perpendicularly outward in the radial direction. It consists of an annular part 11c and is formed in a substantially L-shaped cross section. The slinger 11 has an annular shape as a whole, and is formed by, for example, pressing (drawing) a metal plate such as stainless steel. Further, the cylindrical portion 11a of the slinger 11 is opposed to the cylindrical portion 12a of the core metal 12 with an interval, and the annular portion 11c of the slinger 11 is opposed to the annular portion 12c of the core metal 12 with an interval. A sealing device 7 is assembled to the rolling bearing device 1.

  The seal portion 13 of the seal member 10 extends from the base portion 13a located in the vicinity of the radially inner end of the annular portion 12c of the core metal 12 toward the outer peripheral surface of the cylindrical portion 11a of the slinger 11, and is in sliding contact with the outer peripheral surface. A radial lip portion 13b and an axial lip portion 13c extending from the base portion 13a toward the side surface on the inner side in the axial direction of the annular portion 11c of the slinger 11 are provided.

  The slinger 11 of the sealing device 7 also has a function as one component of the sensor device 19 for detecting the rotation speed (rotation number) of the inner ring 9. Specifically, the sensor device 19 includes a pulsar ring 20 and a sensor 18. The pulsar ring 20 includes a fixing member constituted by the slinger 11 described above and a magnetized body 15 provided on the annular portion 11c of the fixing member 11, and a side surface (hereinafter referred to as an axially outer side) of the magnetized body 15 in the axial direction. A sensor 18 is provided so as to face the outer surface 15a).

The magnetized body 15 is an annular magnet, for example, a plastic magnet in which a powder of a ferrite magnet or the like is mixed with a thermoplastic resin base material such as PA12, PA6, or PPS. The magnetized body 15 is alternately magnetized with N and S poles in the circumferential direction. The fixing member 11 is integrated with the magnetized body 15 of the present embodiment by insert molding.
The sensor 18 is configured to detect a change in the magnetic field accompanying the rotation of the pulsar ring 20 and output the detection signal to a control unit such as an ECU of the vehicle (not shown).

In the annular portion 11c of the fixing member 11, a hole 21 penetrating the annular portion 11c in the axial direction is formed from the inside in the radial direction. A plurality (preferably eight or more) of the holes 21 are formed at intervals in the circumferential direction of the annular portion 11c.
On the other hand, on the axially inner side surface (hereinafter referred to as “inner side surface”) 15 b of the magnetized body 15, a plurality of projections 16 (the same number as the holes 21) are provided with a spacing in the circumferential direction. And each protrusion 16 is inserted in each hole 21 of the annular part 11c.

FIG. 3 is an enlarged cross-sectional view showing a part of the pulsar ring 20.
The projecting portion 16 of the hole 21 and the magnetized member 15 of the annular portion 11c, it is formed at a position of radius R _g from the axis O of the rolling bearing device 1 (see Figure 1). Moreover, the hole 21 and the protrusion 16 are provided in the radial direction inner side than the detection range by the sensor 18 (refer FIG. 2). Further, the diameter D _{h of the} hole 21 is formed larger than the diameter D _{t of the} protrusion 16. A deformation absorber 30 is provided between the inner peripheral surface of the hole 21 and the outer peripheral surface of the protrusion 16.

  The deformation absorber 30 is made of a material having a lower elastic modulus than that of the magnetized body 15, for example, a polymer material such as rubber having a modulus of elasticity of 4000 MPa or less at 23 ° C., a thermoplastic elastomer, or a thermoplastic resin. The rubber that can be used as the material of the deformation absorber 30 includes nitrile rubber (NBR), acrylic rubber (ACM), isoprene rubber (IR), ethylene propylene rubber (EPM), ethylene propylene diene rubber (EPDM), and chloroprene rubber. (CR), styrene-butadiene rubber (SBR), fluorine rubber (FKM), and the like. Examples of the thermoplastic elastomer include polyester (TPEE), urethane (TPU), amide (TPA), and olefin (TPO). As the thermoplastic resin, polyamide (PA), polyphenylene sulfide (PPS), polyacetal (POM), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyamide imide (PAI), polyether ether ketone (PEEK) In particular, it is preferable to use a thermoplastic resin that does not contain reinforcing fibers. When the deformation absorber 30 is formed of rubber, the Shore hardness is preferably A40 to A60. When the deformation absorber 30 is formed of synthetic resin, the Rockwell hardness is B65. It is preferable that it is -85.

  The deformation absorber 30 has a cylindrical portion 30a disposed along the inner peripheral surface of the hole 21 (the outer peripheral surface of the protrusion 16), and extends in the radial direction from one axial end of the cylindrical portion 30a. It consists of a flange 30b arranged along the side surface (inner surface 15b of the magnetized body 15). And the deformation | transformation absorber 30 is attached to the annular part 11c by press-fitting the cylinder part 30a to the internal peripheral surface of the hole 21, or adhere | attaching with an adhesive agent.

  And the magnetized body 15 is integrated by insert molding with respect to the annular part 11c of the fixing member 11 to which the deformation absorber 30 is attached. In particular, the magnetized body 15 is firmly connected to the annular portion 11c by inserting the protrusion 16 into the hole 21 of the annular portion 11c.

  Since the magnetized body 15 and the fixing member 11 are formed of different materials, the coefficients of thermal expansion are different from each other, and the amounts of thermal deformation (thermal expansion and thermal contraction) due to ambient temperature changes are also different. Therefore, when the protrusion 16 of the magnetized body 15 is in direct contact with the hole 21 of the annular portion 11c, stress is concentrated on the protrusion 16 due to the difference in thermal deformation between the magnetized body 15 and the fixing member 11. However, there is a possibility that the magnetized body 15 will be cracked starting from the protrusion 16. However, in this embodiment, since the deformation absorber 30 is provided between the protrusion 16 and the hole 21, the deformation absorber 30 absorbs the difference in the amount of thermal deformation between the magnetized body 15 and the fixing member 11. It is possible to prevent stress from concentrating on the protrusion 16.

  Moreover, since the deformation | transformation absorber 30 consists of the cylinder part 30a and the collar part 30b, the protrusion 16 is covered in the range including the root part 16a. Therefore, it is possible to reliably prevent stress from concentrating around the root portion 16a of the protrusion 16, and to prevent cracking of the magnetized body 15 starting from the root portion 16a.

Further, the protrusion 16 is formed to be longer than the depth of the hole 21 (the thickness of the annular portion 11c), and the tip portion 16b protrudes from the inner side surface (left side surface in FIG. 3) of the annular portion 11c. . Thereby, the protrusion 16 becomes difficult to detach | leave from the hole 21, and the magnetic body 15 can be firmly attached to the annular part 11c.
Further, by providing the deformation absorber 30 made of a polymer material between the hole 21 and the protrusion 16, it becomes possible to prevent moisture from entering between the fixing member 11 and the magnetized body 11. .

In addition, the dimension of each part of the deformation | transformation absorber 30 can be set as follows.
Thickness _{t e} of the cylindrical portion 30a and the flange portion 30b of the deformation absorber 30 can be set by the equation (1).
_{R g (ρ p -ρ s)} (T max -T min) <t e <D h / 2 ··· (1)

Here, R _g is the radius of the hole 21 and the protrusion 16 centering on the axis O (see FIG. 1) of the rolling bearing device 1, ρ _p is the linear expansion coefficient of the magnetized body 15, and ρ _s is fixed. The linear expansion coefficient of the member 11, T _max is the use upper limit temperature, T _min is the use lower limit temperature, and D _h is the diameter of the hole 21.
By thus the wall thickness t _e of the deformation absorber 30 is set, it is possible to properly absorb the difference of thermal deformation of the fixing member 11 and the magnetized member 15.

The diameter D _e of the flange portion 30b of the deformation absorber 30 is preferably set as in the following equation (2).
_{D h <D e <D h} + 2t s ··· (2)
Here, _{t s} is the thickness of the fixing member 11.

By thus diameter D _e of the flange portion 30b is set, without peripheral angle portion of the hole 21 is in direct contact with magnetized body 15, also, the flange portion 30b is radially inward beyond the stationary member 11 It does not protrude in the direction.

The present invention is not limited to the above-described embodiment, and can be appropriately changed within the scope of the invention described in the claims.
For example, the number of holes 21 formed in the fixing member 11 and the number of protrusions 16 formed on the magnetized body 15 can be changed as appropriate. Further, in order to more reliably prevent the protrusion 16 from detaching from the hole 21, the distal end portion 16 b of the protrusion 16 protruding from the hole 21 is larger than the outer diameter of the cylindrical portion 30 a or the diameter D _{h of the} hole 21. A diameter retaining portion may be formed.

Moreover, the hole 21 does not need to penetrate the annular part 11c, and the protrusion 16 does not need to protrude from the inner surface of the annular part 11c.
The deformation absorber 30 may be configured only from the cylindrical portion 30a.

  1: rolling bearing device, 3: outer ring, 4: rolling element, 5: rolling element, 9: inner ring (rotating member), 11: slinger (fixing member), 11a: cylindrical part, 11c: annular part, 15: wearing Magnetic body, 16: protrusion, 20: pulsar ring, 21: hole, 30: deformation absorber, 30a: tube, 30b: collar

Claims (6)

It is made of a metal material, and is composed of a cylindrical member and a fixing member having an annular ring portion extending radially outward from one axial end of the cylindrical portion, and a synthetic resin material mixed with a magnetic material, A pulsar ring provided with a magnetized body attached to an axial side surface of the annular portion,
A hole is formed in the side surface of the annular portion,
The magnetic body is formed with a protrusion that connects the annular portion and the magnetic body by being inserted into the hole,
A pulsar ring characterized in that a deformation absorber is provided between the inner surface of the hole and the outer surface of the protrusion to absorb a difference in thermal deformation between the magnetized body and the annular portion.   The pulsar ring according to claim 1, wherein the deformation absorber is formed of a polymer material having a smaller elastic modulus than the magnetized body.   The deformation absorber includes a cylindrical portion disposed along the inner surface of the hole, and a flange portion that extends radially outward from one axial end of the cylindrical portion and is disposed along the side surface of the annular portion. The pulsar ring according to claim 1 or 2, comprising: The hole is formed through the annular portion in the axial direction;
The pulsar ring according to any one of claims 1 to 3, wherein the protrusion protrudes from a side surface opposite to the side surface of the annular portion.   The pulsar ring according to any one of claims 1 to 4, wherein a plurality of the holes and the protrusions are provided at intervals in the circumferential direction with respect to the annular portion and the magnetized body, respectively. Inner ring,
An outer ring disposed radially outward of the inner ring;
A plurality of rolling elements provided between the inner ring and the outer ring so as to be capable of rolling;
A rolling bearing device comprising the pulsar ring according to any one of claims 1 to 5, which is attached to an outer peripheral surface of the inner ring.

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