JP5365350B2 - Sealing device and rolling bearing - Google Patents

Description

  The present invention relates to a sealing device. In particular, the present invention relates to a rolling bearing in which a raceway member having a raceway surface includes only a plurality of cylindrical members, a rolling bearing in which a raceway member having a raceway surface includes a shaft member (for example, a rolling bearing for wheels), a water pump, or The present invention relates to a sealing device suitable for use in a motor using a rolling bearing. The present invention also relates to a rolling bearing provided with a sealing device.

  Conventionally, as a sealing device, there is one described in JP 2003-222145 A (Patent Document 1).

  This sealing device seals between an outer ring and an inner shaft in a hub unit (wheel rolling bearing). The sealing device includes a cored bar member and an elastic member fixed to the cored bar member. The cored bar member has a cylindrical portion and a radially extending portion, and the cylindrical portion is fitted and fixed to the inner peripheral surface of the outer ring. Moreover, the said radial direction extension part is extended in the substantially radial direction of the said cylindrical part from the said cylindrical part.

  On the other hand, the elastic member has a base, two axial lips, and a grease lip, and the base is fixed to the radially extending portion. Each of the axial lips extends from the base portion and slides on an end surface of the inner shaft in the axial direction. The grease lip extends from the base inward in the radial direction and on the opposite side of the end surface of the inner shaft in the axial direction, and is spaced from the outer peripheral surface of the inner shaft. ing. The grease lip and the outer peripheral surface of the inner ring constitute a labyrinth seal.

Japanese Patent Laying-Open No. 2003-222145 (FIG. 1)

  In the sealing device having the above-described configuration, abnormal wear occurs in the axial lip due to the following phenomenon, or the axial lip surface pressure against the end surface of the inner shaft increases, and torque is generated due to the large surface pressure. May increase.

  Specifically, when the vehicle or the like equipped with the hub unit is operated and the temperature of the sealed space sealed by the sealing device rises, the air in the sealed space passes through the sealing device and is discharged outside. And then, when the vehicle or the like stops and the temperature in the sealed space decreases, the pressure in the sealed space becomes negative with respect to the external atmospheric pressure, and this negative pressure causes The axial lip may be pressed against the end surface of the inner shaft, and the axial lip may be attracted to the end surface of the inner shaft.

  Then, due to the adsorption of the axial lip to the end surface of the inner shaft, the tip of the axial lip may be abnormally worn, shortening the life of the axial lip, increasing the temperature, or generating abnormal noise. is there. In addition, due to the adsorption of the axial lip to the end surface of the inner shaft, the contact surface pressure of the axial lip with respect to the end surface of the inner shaft may increase, and the torque may increase.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a sealing device in which even if a pressure difference occurs between the inside and outside of the lip, the lip is hardly adsorbed on the sliding member, the lip is less likely to wear, and torque can be suppressed. There is. Moreover, this invention is providing a rolling bearing provided with such a sealing device.

In order to solve the above problems, the sealing device of the present invention is
A cored bar member having a cylindrical part and an annular radial extending part extending from the cylindrical part in a substantially radial direction of the cylindrical part;
An elastic member fixed to the core member,
The elastic member is
A base fixed to the at least part of the core metal member so as to cover at least part of the surface of the core metal member;
An annular first lip extending from the base and sliding on the sliding member;
An annular ring extending from the base and sliding on the slidable member, or forming a labyrinth in a non-contact manner against the slidable member and spaced from the first lip The second lip of
And the first lip, and coupling the second lip, and have a plurality of connecting portions positioned at a distance from one another in the circumferential direction,
Each of the connecting portions extends in the radial direction and does not extend in the circumferential direction .

  According to the present invention, the elastic member connects the first lip and the second lip, and has a plurality of connecting portions that are spaced from each other in the circumferential direction. And the rigidity of the second lip is locally increased. That is, the connecting portion can apply a force for suppressing the deformation of the first lip to the first lip, and can also apply a force for suppressing the deformation of the second lip to the second lip. Therefore, for example, by driving a vehicle or the like equipped with the sealing device of the present invention, the temperature of the sealing side sealed by the sealing device returns to room temperature after the temperature becomes higher than the outside temperature, and enters and exits the sealing device. Even if a pressure difference occurs, when the second lip slides on the sliding member due to the force from the connecting portion, the first and second lips are excessively deformed so as to be attracted to the sliding member. In addition, when the second lip forms a labyrinth so as to face the sliding member in a non-contact manner, the first lip can be prevented from being excessively deformed to be attracted to the sliding member. Therefore, when the second lip slides on the sliding member, the first and second lips do not cause abnormal wear of the first and second lips when a pressure difference occurs between the inside and the outside of the sealing device. The wear of the first and second lips can be extended. In addition, when the second lip forms a labyrinth in a non-contact manner against the sliding member, when there is a pressure difference between the inside and outside of the sealing device, abnormal wear of the first lip does not occur, Wear of the first lip can be suppressed, and the life of the first lip can be extended. Further, since the lip is not attracted to the sliding member, when the second lip slides on the sliding member, the contact surface pressure of the first and second lips against the sliding member becomes excessive. The torque can be suppressed. Further, since the lip is not attracted to the sliding member, the contact surface of the first lip with respect to the sliding member is formed when the second lip forms a labyrinth so as not to contact the sliding member. Torque can be suppressed without excessive pressure.

The rolling bearing of the present invention is
A sealing device of the present invention;
A first race member having a circumferential surface to which the cylindrical portion is fixed, and a raceway surface;
A second track member that includes the slide member or is fixed to the slide member and has a track surface;
A rolling element is provided between the raceway surface of the first raceway member and the raceway surface of the second raceway member.

  According to the present invention, the lifetime of the sealing device can be extended. Moreover, the torque resulting from the sliding resistance of the sealing device with respect to the second track member can be reduced, and the fuel consumption of the device including this rolling bearing can be reduced.

  According to the sealing device of the present invention, even if a pressure difference occurs between the inside and outside of the lip, the lip can be prevented from adsorbing to the sliding member, and wear of the lip can be suppressed. Further, since the lip is not attracted to the sliding member and the contact surface pressure of the first lip or the first lip to the sliding member does not become excessive, the torque can be suppressed.

It is sectional drawing of the axial direction of the rolling bearing for wheels which is 1st Embodiment of this invention. It is a partial expanded sectional view of the 1st sealing device periphery in FIG. It is the figure which showed only the elastic member in the AA sectional view taken on the line of FIG.

  Hereinafter, the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a sectional view in the axial direction of a wheel rolling bearing according to a first embodiment of the present invention.

  The wheel rolling bearing includes an outer ring 2 as a first race member, an inner shaft 3 as a second race member, an inner ring 4, a plurality of first balls 5, a plurality of second balls 6, and the first embodiment. A first sealing device 8 and a second sealing device 9 are provided. The said 1st ball | bowl 5 and the 2nd ball | bowl 6 comprise a rolling element. The inner shaft 3 is a sliding member.

  The inner shaft 3 has a disc-shaped brake disk mounting flange 10 extending in the radial direction for mounting the brake disk 11 at one end in the axial direction. A plurality of bolt through holes are formed on a concentric circle centered on the approximate center of the brake disk mounting flange 10. With the brake disk 11 in contact with the brake disk mounting flange 10 and with the wheel member 13 in contact with the brake disk 11, an end surface of the wheel member 13 opposite to the brake disk 11 side; The brake disk mounting flange 10 is fixed with a plurality of bolts 15.

  An inner ring 4 is externally fitted and fixed to the other axial end portion of the inner shaft 3. An angular type raceway groove 16 as a raceway surface is formed between the inner ring 4 and the brake disc mounting flange 10 in the inner shaft 3. An angular type raceway groove 17 as a raceway surface is formed on the outer peripheral surface of the inner ring 4.

  The outer ring 2 is disposed on the other end side of the brake disc mounting flange 10 in the inner shaft 3 so as to face the inner shaft 3 in the radial direction. The outer ring 2 has a vehicle body side mounting flange 14 extending in the radial direction on the other end side in the axial direction. A plurality of bolt through holes for inserting bolts for attaching the vehicle body side mounting flange 14 to the vehicle body side (knuckle) are formed in the disk-shaped vehicle body side mounting flange 14. The outer ring 2 has an angular first raceway groove 26 as a first raceway surface and an angular second raceway groove 27 as a second raceway surface, which are spaced apart in the axial direction on the inner peripheral surface of the outer ring 2. doing. The first track groove 26 is located on the one end side with respect to the second track groove 27.

  The plurality of first balls 5 are spaced by a predetermined interval in the circumferential direction while being held by the cage 18 between the raceway groove 16 of the inner shaft 3 and the first raceway groove 26 of the outer ring 2. Are arranged. The plurality of second balls 6 are spaced by a predetermined interval in the circumferential direction while being held by the cage 19 between the raceway groove 17 of the inner ring 4 and the second raceway groove 27 of the outer ring 2. Has been placed.

  The first sealing device 8 is disposed in the vicinity of the opening on the one end side (the brake disc mounting flange 10 side) in the axial direction between the inner shaft 3 and the outer ring 2. The first sealing device 8 seals the opening on the one end side between the inner shaft 3 and the outer ring 2.

  On the other hand, the second sealing device 9 is disposed in the vicinity of the opening on the other end side (the vehicle body mounting flange 14 side) in the axial direction between the inner ring 4 and the outer ring 2. The second sealing device 9 seals the opening on the other end side between the inner ring 4 and the outer ring 2.

  FIG. 2 is a partially enlarged cross-sectional view around the first sealing device 8 in FIG.

  As shown in FIG. 2, the first sealing device (hereinafter simply referred to as a sealing device) 8 includes a metal cored bar member 40 and a rubber elastic member 41. The sealing device 8 is formed by integrally molding the core metal member 40 and the elastic member 41 by vulcanization molding using injection molding. The core metal member 40 includes a cylindrical portion 60 and a radially extending portion 61. The tubular portion 60 is fitted and fixed to the end of the inner peripheral surface of the outer ring 2 on the brake disc mounting flange 10 side. The radially extending portion 61 extends from the tubular portion 60 in the substantially radial direction of the tubular portion 60.

  On the other hand, the elastic member 41 has a base 50, an annular first axial lip 51, an annular second axial lip 52, an annular radial lip 53, a plurality of first connecting parts 54 and a plurality of second connecting parts 55. The base portion 50 is fixed to the radially extending portion 61.

  The first axial lip 51 is located on the outer side in the radial direction than the second axial lip 52. Each of the first axial lip 51 and the second axial lip 52 extends from the base portion 50 to the brake disc mounting flange 10 side in the axial direction and to the outer ring 2 side in the radial direction (outward side in the radial direction). . Each of the first axial lip 51 and the second axial lip 52 slides on the end face 59 on the first ball 5 side in the axial direction of the brake disk mounting flange 10.

  On the other hand, the radial lip 53 extends from the base portion 50 toward the first ball 5 (see FIG. 1) in the axial direction and toward the inner side in the radial direction. The radial lip 53 slides on the outer peripheral surface of the inner shaft 3.

  Each of the first connecting portions 54 has a curtain shape. Each said 1st connection part 54 has connected between the internal peripheral surface of the 1st axial lip 51, and the outer peripheral surface of the 2nd axial lip 52 in the shape of a scooping. Each said 1st connection part 54 exists on the plane containing a radial direction and the direction perpendicular | vertical to the circumferential direction. In the use state of the sealing device 8, the first connecting portions 54 are located at a distance from the inner shaft 3. The plurality of first connecting portions 54 are arranged at equal intervals in the circumferential direction of the sealing device 8.

  In the first connecting portion 54, the first axial lip 51 and the second axial lip 52 are positioned at predetermined positions, and an end face 59 of a brake disc mounting flange portion (hereinafter simply referred to as a flange portion) 10. When the first axial lip 51 is deformed by receiving a force from the first axial lip 51, the first axial lip 51 is imparted with a force to suppress the deformation of the first axial lip 51, and the second axial lip 52 has a force to suppress the deformation of the second axial lip 52. 52.

  Each of the first axial lip 51 and the second axial lip 52 is deformed to a degree smaller than that which would have occurred if the first connecting portion 54 was not present.

  Further, after the sealing device 8 is assembled to the outer ring 2 and the inner shaft 3, when a pressure difference occurs between the inside and outside of the first axial lip 51, the first axial lip 51 is provided with the first connecting portion 54. Therefore, the force based on the pressure difference is relieved and excessive deformation is not generated based on the pressure difference.

  In addition, after the sealing device 8 is assembled to the outer ring 2 and the inner shaft 3, when a pressure difference occurs between the inside and outside of the second axial lip 52, the second axial lip 52 has the presence of the first connecting portion 54. Therefore, the force based on the pressure difference is relieved and excessive deformation is not generated based on the pressure difference.

  Each of the second connecting portions 55 has a curtain shape. Each of the second connecting portions 55 connects the annular surface of the second axial lip 52 on the radial lip 53 side and the annular surface of the radial lip 53 on the second axial lip 52 side in a scooping manner.

  Each said 2nd connection part 55 exists on the plane containing a radial direction and the direction perpendicular | vertical to the circumferential direction. In the use state of the sealing device 8, each second connecting portion 55 is located at a distance from the inner shaft 3. The plurality of second connecting portions 55 are arranged at equal intervals in the circumferential direction of the sealing device 8.

  When the second axial lip 52 and the radial lip 53 are positioned at predetermined positions and receive a force from the end surface 59 or the outer peripheral surface of the flange portion 10 to deform the second connecting portion 55, A force for suppressing the deformation of the axial lip 52 is applied to the second axial lip 52, and a force for suppressing the deformation of the radial lip 53 is applied to the radial lip 53.

  Each of the second axial lip 52 and the radial lip 53 is deformed to a degree smaller than that which would have occurred if the second connecting portion 55 was not present.

  Further, after the sealing device 8 is assembled to the outer ring 2 and the inner shaft 3, when a pressure difference occurs between the inside and outside of the second axial lip 52, the second axial lip 52 is provided with the second connecting portion 55. Therefore, the force based on the pressure difference is relieved and excessive deformation is not generated based on the pressure difference.

  In addition, after the sealing device 8 is assembled to the outer ring 2 and the inner shaft 3, when a pressure difference occurs between the inside and outside of the radial lip 53, the radial lip 53 has the above atmospheric pressure due to the presence of the second connecting portion 55. A force that reduces deformation based on the difference is received, and excessive deformation does not occur based on the pressure difference.

  FIG. 3 is a diagram showing only the elastic member 41 in the cross-sectional view taken along the line AA in FIG.

  As shown in FIG. 3, there are six first connecting portions 54, and six first connecting portions 54 are equally arranged in the circumferential direction. There are also six second connecting portions 55, and the six second connecting portions 55 are equally arranged in the circumferential direction. The said 1st connection part 54 and the 2nd connection part 55 are formed in the location of the same phase of the circumferential direction.

  According to the sealing device 8 of the above-described embodiment, the elastic member 41 connects the first axial lip 51 and the second axial lip 52 in the form of a scrubbing shape, and a plurality of first members positioned at intervals in the circumferential direction. Since the first connecting portion 54 is provided, the first connecting portion 54 can locally increase the rigidity of the first axial lip 51 and the second axial lip 52. That is, the first connecting portion 54 can apply a force for suppressing the deformation of the first axial lip 51 to the first axial lip 51, and suppress the deformation of the second axial lip 52 to the second axial lip 52. Can give power. Therefore, due to the operation of the rolling bearing for the vehicle, the temperature on the sealed side sealed by the sealing device 8 returns to room temperature after becoming higher than the external temperature, and a pressure difference occurs inside and outside the sealing device 8. However, it is possible to prevent the first and second axial lips 51 and 52 from being excessively deformed to be attracted to the end surface 59 of the inner shaft 3 by the force from the first connecting portion 54. Therefore, when the pressure difference between the inside and outside of the sealing device 8 is generated, the first and second axial lips 51 and 52 are not abnormally worn, and the first and second axial lips 51 and 52 are prevented from being worn. The life of the first and second axial lips 51, 52 can be extended. Further, since the first and second axial lips 51 and 52 are not attracted to the end surface 59 of the inner shaft 3, the contact surface pressure of the first and second axial lips 51 and 52 with respect to the inner shaft 3 becomes excessive. The torque can be suppressed.

  Further, according to the sealing device 8 of the above-described embodiment, the elastic member 41 connects the second axial lip 52 and the radial lip 53 in the form of a scrubbing shape, and a plurality of second members positioned at intervals in the circumferential direction. Since the second connecting portion 55 is provided, the second connecting portion 55 can locally increase the rigidity of the second axial lip 52 and the radial lip 53. That is, the second connecting portion 55 can give the second axial lip 52 a force for suppressing the deformation of the second axial lip 52, and can give the radial lip 53 a force for suppressing the deformation of the radial lip 53. . Therefore, due to the operation of the rolling bearing for the vehicle, the temperature on the sealed side sealed by the sealing device 8 returns to room temperature after becoming higher than the external temperature, and a pressure difference occurs inside and outside the sealing device 8. Even so, it is possible to prevent the second axial lip 52 and the radial lip 53 from being excessively deformed so as to be attracted to the end surface 59 of the inner shaft 3 by the force from the second connecting portion 55. Therefore, when the pressure difference between the inside and outside of the sealing device 8 is generated, the second axial lip 52 and the radial lip 53 are not worn abnormally, and the second axial lip 52 and the radial lip 53 are prevented from wearing. The life of the second axial lip 52 and the radial lip 53 can be extended. Further, since the second axial lip 52 is not attracted to the end surface 59 of the inner shaft 3, the contact surface pressure of the second axial lip 52 with respect to the inner shaft 3 does not become excessive, and torque is suppressed. be able to. Similarly, since the radial lip 53 is not attracted to the outer peripheral surface of the inner shaft 3, the contact surface pressure of the radial lip 53 with respect to the inner shaft 3 does not become excessive, and torque is suppressed. Can do.

  In the sealing device 8 of the above embodiment, the six first and second connecting portions 54 and 55 are formed at substantially equal intervals in the circumferential direction. However, in the present invention, a plurality of integer connecting portions other than 6 are provided. Further, they may be arranged at substantially equal intervals in the circumferential direction, and two or more connecting portions may be formed at intervals that are not equally spaced in the circumferential direction.

  In the sealing device 8 of the above embodiment, the number of the first connecting portions 54 and the number of the second connecting portions 55 are the same, and the first connecting portions 54 and the second connecting portions 55 In the present invention, the number of the first connection portion and the number of the second connection portions may not be the same, and the first connection portion and the second connection portion may be the same. The connecting portion may not be formed at the same phase in the circumferential direction.

  Further, in the sealing device 8 of the above embodiment, the first and second connecting portions 54 and 55 are located at a distance from the inner shaft 3 in use, but in the present invention, the connecting portion is a sealing device. In use, the sliding member may be in contact.

  Further, in the sealing device 8 of the above embodiment, the first and second connecting portions 54 and 55 exist on a plane including the radial direction and the direction perpendicular to the circumferential direction. It does not have to exist on a plane including the radial direction and the direction perpendicular to the circumferential direction. In the present invention, the connecting portion only needs to connect two lips.

  In the sealing device 8 of the above embodiment, the axial lips 51 and 52 slide on the axial end surface 59 (see FIG. 2) of the inner shaft 3, but in the present invention, at least one lip is used. Is the outer peripheral surface of the inner shaft, the axial end surface of the flange portion of the slinger (a member having a substantially L-shaped cross section in the axial half cross section), the peripheral surface of the slinger, the axial end surface of the inner ring, It may be configured to slide on the outer peripheral surface, the axial end surface of the outer ring, the inner peripheral surface of the outer ring, or the like.

  In the sealing device 8 of the above embodiment, the first axial lip 51 and the second axial lip 52 are connected by the first connecting portion 54, and the second axial lip 52 and the radial lip 53 are connected by the first connecting portion 54. The two connecting portions 55 were connected. However, the sealing device of the present invention may have only a connecting portion that connects the axial lip and the axial lip. Further, the sealing device of the present invention may have only a connecting portion that connects the axial lip and the radial lip. In this specification, a radial lip is defined as a lip that is in sliding contact with the peripheral surface.

  In the present invention, the sealing device has three or more axial lips, and the connecting portion has two or more spaces formed by the three or more axial lips (an axial lip and an axial lip adjacent to the axial lip). (Space). More specifically, when the sealing device according to the present invention has N (natural number of 2 or more) lips, any one of the spaces between the lips and the lip existing at (N-1) or less, It may be arranged in any two or more spaces.

  Further, the sealing device 8 of the present invention has three contact seals. In the present invention, however, the seal device 8 has two or more lips, and further, a non-contact seal (labyrinth seal) in the two or more lips. May be included. For example, a screed-like (curtain-like) connecting portion may be formed between the contact seal and the labyrinth seal. However, at least one of the seals connected by the connecting portion needs to be a contact seal.

  Further, in the wheel rolling bearing described above, the sealing device 8 of the present invention is disposed in the vicinity of the opening on one end side in the axial direction of the ball arrangement chamber. You may arrange | position only in the vicinity of the opening of the axial direction both sides of a moving body arrangement | positioning chamber (lubricant enclosure chamber), or the other end side of an axial direction.

  Moreover, in the said embodiment, although the rolling bearing was a rolling bearing for wheels which has the inner shaft 3, the rolling bearing of this invention is a structure which a member which has a raceway surface consists only of multiple (2 or more) cylindrical members. It may be. Also. The rolling bearing of the present invention may be a water pump, a motor, or the like, and may be any rolling bearing having a rolling element and a raceway surface (in this specification, a rolling bearing is referred to as a rolling element). , Defined as a device having a raceway surface on which this rolling element rolls). Further, in the rolling bearing of the present invention, the rolling elements may not be balls but may be rollers, or may be both balls. The rolling element is a roller, including a case where the rolling element is a tapered roller, a case where it is a cylindrical roller, and a case where it is a convex roller, but when the rolling element is a roller, the rolling element is a tapered roller. And preferred. In the rolling bearing of the present invention, the first race member may be an integral member or a plurality of members, and the second race member may be an integral member or a plurality of members. May be. In the rolling bearing of the present invention, the rolling elements may be arranged in a single row, or the rolling elements may be arranged in two or more rows.

2 outer ring 3 inner shaft 4 inner ring 5 first ball 6 second ball 8 sealing device 40 metal core member 41 elastic member 50 base 51 first axial lip 52 second axial lip 53 radial lip 54 first connecting portion 55 second Connection part 60 Tubular part 61 Radial extension part

Claims (2)

A cored bar member having a cylindrical part and an annular radial extending part extending from the cylindrical part in a substantially radial direction of the cylindrical part;
An elastic member fixed to the core member,
The elastic member is
A base fixed to the at least part of the core metal member so as to cover at least part of the surface of the core metal member;
An annular first lip extending from the base and sliding on the sliding member;
An annular ring extending from the base and sliding on the slidable member, or forming a labyrinth in a non-contact manner against the slidable member and spaced from the first lip The second lip of
And the first lip, and coupling the second lip, and have a plurality of connecting portions positioned at a distance from one another in the circumferential direction,
Each said connection part is extended in the said radial direction, and does not extend in the said circumferential direction, The sealing device characterized by the above-mentioned . A sealing device according to claim 1;
A first race member having a circumferential surface to which the cylindrical portion is fixed, and a raceway surface;
A second track member that includes the slide member or is fixed to the slide member and has a track surface;
A rolling bearing comprising: a rolling element disposed between the raceway surface of the first raceway member and the raceway surface of the second raceway member.

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