JP2010025253A - Sealing device for rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealing device for a rolling baring, reducing wear of a seal by reducing the sliding torque of an axial lip, and improving water resistance. <P>SOLUTION: A seal lip 28 being in slidable contact with an inner ring 12 is formed on the inner periphery of the seal 20 of the rolling bearing 10, the seal 20 has a flat side surface 30 positioned radially outward of the seal lip 28, the surface of a slinger 40, opposed to the seal 20, has a flat surface 44, and the flat surface 44 is formed with a bent projection 46 with a part thereof axially bent and projected inward of the bearing. Further, a labyrinth is formed in a state that the side surface 30 of the seal 20 and the bent projection 46 of the slinger 40 come close to each other without contact. Further, the side surface 30 of the seal 20 is formed with the axial lip 32 extending outward of the bearing. The end of the axial lip is brought into contact with the flat surface 44 of the slinger 40 at a position radially inward of a position with the bent projection 46 of the slinger 40 formed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rolling bearing sealing device. More specifically, the present invention relates to a rolling bearing sealing device in which a space between an inner ring and an outer ring is covered with a seal and a slinger is provided outside the seal.

Bearings for idlers used in engine peripheral accessories for automobiles, such as those used in idler pulleys, are annular seals to prevent foreign matter such as water and dust from entering the bearings. In addition to covering between the outer ring and the inner ring, a sealing plate called a slinger is provided on the outer side of the seal, and a sealing device is configured so that water and dust are not directly applied to the seal. In order to allow relative rotation between the inner ring and the outer ring, the outer periphery of the seal is fixed to the outer ring, and a seal lip is provided on the inner periphery of the seal so as to be in sliding contact with the inner ring.
Here, since the idler bearing is used at high speed rotation, the seal lip needs to be a light contact type having a small amount of interference to prevent heat generation at the sliding portion of the seal.
For this reason, simply sealing the outer ring and the inner ring with a seal and sliding the seal against the inner ring and providing a slinger on the outside of the seal does not provide sufficient sealing against the ingress of water or dust from the outside. It is difficult to prevent dust from entering the inside of the bearing from between the seal lip and the inner ring.

Therefore, in order to improve the water resistance of the bearing, an axial lip may be formed to extend axially outward from the seal, and the axial lip may be brought into contact with the slinger to close the gap between the seal and the slinger. .
For example, Japanese Patent Laying-Open No. 2004-11732 (Patent Document 1) describes a bearing sealing structure in which a seal has an axial lip.
FIG. 4 shows a sealing structure using a seal main body 110 and a slinger 105 having substantially the same structure as the bearing sealing structure described in Patent Document 1. The seal body 110 is formed with a seal lip 120 slidably in contact with a portion parallel to the axis of the slinger 105 on the inner peripheral side, and an axial lip 112 slidably in contact with a portion perpendicular to the axis of the slinger 105 axially outward. . Since this axial lip 112 contacts the slinger 105 and blocks the path where foreign matters such as water and dust reach the periphery of the seal lip 120, the waterproofness and dustproofness of the bearing are improved, and the sealing performance of the bearing is expected to be improved. it can.
Japanese Patent Laid-Open No. 2004-11732

However, in the configuration in which the axial lip is brought into contact with the slinger, it is necessary to increase the tightening margin in order to improve the sealing performance, and there is a problem that the rotational torque of the bearing is increased.
In a configuration where the seal is fixed to the outer ring and rotates integrally with the outer ring, and the axial lip expands radially outward and contacts the slinger from the outer diameter side, the axial lip is formed on the outer diameter side. The centrifugal force acting in the direction of pulling the axial lip away from the slinger is increased, and there is a problem that a gap is formed between the axial lip and the slinger.

  Accordingly, an object of the present invention is to provide a rolling bearing sealing device in which the sliding torque of the axial lip is lowered to reduce the wear of the seal, and the water resistance is improved.

In order to solve the above problems, the rolling bearing sealing device according to the present invention takes the following means.
First, the first invention of the present invention comprises a seal fixed to the outer ring, and a slinger disposed coaxially with the inner ring outside the bearing of the seal, and a gap formed by the seal and the slinger is the A rolling bearing sealing device configured to open to the outside of the bearing at the outer diameter side end of the slinger,
A seal lip configured to be in sliding contact with the inner ring is formed on the inner peripheral edge of the seal, and a radially outer side of the seal is a flat side surface than a position where the seal lip is formed,
The surface of the slinger that faces the seal is a flat surface, and a bent convex portion is formed on the flat surface of the slinger by bending a part thereof in the axial direction and projecting inward of the bearing. The side surface of the seal and the bent convex part of the slinger are in a non-contact proximity state to form a labyrinth,
An axial lip is formed on the side surface of the seal so as to extend outward of the bearing, and the tip of the axial lip is radially inward from the position where the bending projection of the slinger is formed. The slinger is configured to be in contact with the flat surface.

According to the first aspect of the present invention, the flat surface of the slinger that contacts the tip of the axial lip is on the inner diameter side of the bearing in the radial direction of the bearing with respect to the bending convex portion of the slinger, so that the axial surface that contacts the flat surface of the slinger The diameter of the tip of the lip is small, and the sliding area between the axial lip and the slinger is small. And since the peripheral speed by relative rotation of an axial lip and a slinger becomes small, a torque can be reduced and abrasion of an axial lip can be reduced. Further, since heat generation due to sliding between the axial lip and the slinger is reduced and the heat resistance of the seal is alleviated, it is possible to use a material having a low heat resistance for the seal.
Since the axial lip contacts the flat surface of the slinger and closes the gap between the seal and the slinger, the water or dust that has entered the gap between the seal and the slinger from the opening of the bearing on the outer diameter side end of the slinger It is possible to prevent foreign matter from entering the periphery of the seal lip radially inward of the bearing from the position where the axial lip is formed.
The labyrinth formed by the side surface of the seal and the bending projection of the slinger causes foreign matter such as water and dust that has entered the gap between the seal and the slinger from the opening of the bearing on the outer diameter side end of the slinger to bend the slinger. It is possible to prevent the axial lip radially inward from the convex portion and the flat portion of the slinger from entering the contact portion. And the rigidity of the slinger in the state which attached the slinger to the bearing can be improved by forming a bending convex part in a slinger.

Next, a second invention of the present invention is a rolling bearing sealing device according to the first invention,
A protruding portion is formed at the radially outer end of the side surface of the seal toward the outer side of the bearing, and the protruding portion is brought into a non-contact proximity state with the outer diameter side end portion of the slinger. It is the structure which forms.

According to the second aspect of the present invention, the labyrinth formed by the protrusion formed on the radially outer end of the seal and the outer diameter side end of the slinger, the seal and the slinger are separated from the outer diameter side end of the slinger. Intrusion of foreign matter such as water into the gap is suppressed.
And since the protrusion part of a seal | sticker can be utilized as a position hold | maintained when accommodating a seal | sticker in a bearing, it can hold | maintain an axial lip at the time of seal | sticker accommodation, and can prevent deforming an axial lip.

According to each invention of the present invention described above, the following effects can be obtained.
First, according to the first invention described above, the axial lip is formed on the inner diameter side of the bearing, and the peripheral speed due to the relative rotation between the axial lip and the slinger is reduced. Wear can be reduced. And the heat_generation | fever by sliding reduces and the heat resistance of a seal | sticker is eased. Further, the labyrinth is formed by the side surface of the seal formed radially outward of the axial lip and the bent convex portion of the slinger, so that intrusion of foreign matters such as water into the periphery of the axial lip is suppressed. And the rigidity of a slinger can be improved with a bending convex part.
Next, according to the second invention described above, the labyrinth formed by the protrusion formed at the radially outer end of the seal and the outer diameter side end of the slinger is sealed from the outer diameter side end of the slinger. Intrusion of foreign matter such as water into the gap between the slinger and the slinger is suppressed. Further, the protrusion can be used as a position for holding the seal when it is accommodated in the bearing.
Therefore, the sliding torque of the axial lip can be lowered to reduce the wear of the seal, and the water resistance can be improved.

  Hereinafter, the best mode for carrying out the present invention will be described according to examples.

FIG. 1 shows a partial cross-sectional view of an idler pulley 50 that uses a rolling bearing 10 provided with a rolling bearing sealing device in Embodiment 1 of the present invention. FIG. 2 shows an enlarged view of the sealing device portion of the rolling bearing 10 shown in FIG.
As shown in FIGS. 1 and 2, the rolling bearing 10 is an outer ring rotating type double row ball bearing used for the idler pulley 50, and holds the inner ring 12, the outer ring 14, the double row ball 16, and the ball 16. The cage 18 includes a seal 20 that covers the space between the inner ring 12 and the outer ring 14, and a slinger 40 that is provided outside the bearing of the seal 20. Among these components, the inner ring 12, the outer ring 14, the seal 20 and the slinger 40 form a sealing device that seals the rolling bearing 10.

  The seal 20 is an annular member in which the outer side of the bearing of the metal cored bar 22 is covered with a rubber covering portion 24, and a fixing portion 26 for attaching the seal 20 to the outer ring 14 at the outer peripheral edge portion of the seal 20. Is formed. The fixing portion 26 is attached to the seal groove 15 provided on the inner diameter surface of the outer ring 14, and the seal 20 is fixed to the outer ring 14. A seal lip 28 is formed inside the bearing at the inner peripheral edge of the seal 20, and the seal lip 28 is in sliding contact with a sliding contact surface 13 formed perpendicular to the axial direction on the outer diameter side of the inner ring 12. . When the seal 20 rotates at a high speed together with the outer ring 14, the seal lip 28 rotates at a high speed while being in sliding contact with the sliding contact surface 13 of the inner ring 12. Therefore, the seal lip 28 is lightly contacted with the sliding contact surface 13 in order to reduce wear of the seal lip 28.

  As shown in FIG. 2, the axially outer side between the fixing portion 26 of the seal 20 and the seal lip 28 is a flat side surface 30, and the seal lip 28 is formed at the inner diameter side end of the side surface 30. An axial lip 32 is formed so as to extend outward in the axial direction of the bearing adjacent to the radially outward position of the formed position. And the protrusion part 34 is formed in the end of the side surface 30 of the seal | sticker 20 toward the axial direction outward of a bearing.

  The slinger 40 is an annular metal plate, and as shown in FIG. 2, a cylindrical portion 42 is formed on the inner diameter side by bending the inner peripheral edge into a cylindrical shape inward in the axial direction of the rolling bearing 10. The cylindrical portion 42 is press-fitted to the outer diameter side of the inner ring 12, and the slinger 40 is fixed to the inner ring 12. The slinger 40 may be directly fixed to the shaft.

A portion where the slinger 40 faces the seal 20 is a flat surface 44 substantially perpendicular to the axial direction. Then, at the position where the flat surface 44 of the slinger 40 opposes the radially inner side of the side surface 30 of the seal 20, the flat surface 44 is bent in the axial direction, and the bent protrusion is protruded inward of the bearing with respect to the flat surface 44. A portion 46 is formed, and the bent convex portion 46 is configured to reach the outer diameter side end portion 48 of the slinger 40. And the bending convex part 46 of the slinger 40 and the side surface 30 of the seal | sticker 20 are made into the non-contact proximity | contact state, and it is set as the structure which forms a labyrinth.
The outer diameter side end portion 48 of the slinger 40 has a gap between the seal 20, the inner diameter surface of the outer ring 14 and the flange 52 of the idler pulley 50, and is open to the outside of the bearing.

Then, the tip of the axial lip 32 formed at the inner diameter side end of the side surface 30 of the seal 20 is radially inward of the flat surface 44 of the slinger 40 from the position where the bent convex portion 46 of the slinger 40 is formed. It is set as the structure which contacts.
Then, the inner diameter side surface of the protrusion 34 formed at the outer diameter side end of the side surface 30 of the seal 20 is brought into a non-contact proximity state with the outer diameter side end surface of the outer diameter side end portion 48 of the slinger 40. Thus, the labyrinth is formed.

According to the first embodiment, the flat surface 44 of the slinger 40 with which the tip of the axial lip 32 comes into contact is on the inner diameter side of the bearing in the radial direction of the bearing with respect to the bent convex portion 46 of the slinger 40. The diameter of the tip of the axial lip 32 in contact with the surface 44 is small. Therefore, the contact circle diameter between the tip of the axial lip 32, the slinger 40, and the flat surface 44 is reduced. As a result, the peripheral speed due to the relative rotation between the axial lip 32 and the slinger 40 is reduced, so that the torque is reduced and the wear of the axial lip 32 can be reduced. Since heat generated by sliding between the axial lip 32 and the slinger is reduced and the heat resistance of the seal 20 is reduced, it is possible to use a material having a low heat resistance for the seal 20.
And since the axial lip 32 contacts the flat surface 44 of the slinger 40 and closes the gap between the seal 20 and the slinger 40, the seal 20 and the slinger 40 are opened from the bearing opening of the outer diameter side end portion 48 of the slinger 40. It is possible to prevent foreign matters such as water and dust that have entered the gap from entering the periphery of the seal lip 28 radially inward of the bearing from the position where the axial lip 32 is formed.
Further, since the axial lip 32 is in contact with the flat surface 44 of the slinger 40 radially inward from the position where the bent convex portion 46 of the slinger 40 is formed, the side surface 30 of the seal 20 and the bent convex portion of the slinger 40 are arranged. Due to the labyrinth formed by 46, foreign matters such as water and dust that have entered between the seal 20 and the slinger 40 from the opening of the bearing on the outer diameter side end 48 of the slinger 40, the axial lip 32 becomes a flat surface of the slinger 20. It is possible to suppress intrusion into a portion that contacts 44. And the rigidity of the slinger 40 in the state which attached the slinger 40 to the bearing can be improved by forming the bending convex part 46 in the slinger 40. FIG.
Then, the labyrinth formed by the protrusion 34 formed on the outer diameter side end of the side surface 30 of the seal 20 and the outer diameter side end 48 of the slinger 40 is connected to the seal 20 from the outer diameter side end 48 of the slinger 40. Intrusion of foreign matter such as water into the gap of the slinger 40 is suppressed.
Therefore, according to the first embodiment, it is possible to provide a rolling bearing sealing device in which the sliding torque of the axial lip 32 is lowered to reduce the wear of the seal 20 and the water resistance is improved.

  FIG. 3 shows an enlarged view of the sealing device portion of the rolling bearing 10A of the idler pulley using the rolling bearing 10A provided with the rolling bearing sealing device in Embodiment 2 of the present invention. Since the second embodiment is common to the first embodiment except for a part of the configuration of the seal 20A and the slinger 40A, the common portions are denoted by the same reference numerals and the description thereof is omitted.

In the following, parts different from those in the first embodiment will be described. In the slinger 40A, the bent convex portion 46A does not reach the radially outer end of the slinger 40A, and the flat surface 44A is bent at two locations in the radial direction so that the bent convex portion is in the middle of the flat surface 44A in the radial direction. 46A is formed. The bent convex portion 46A of the slinger 40A and the side surface 30 of the seal 20A are brought into a non-contacting proximity state to form a labyrinth.
In addition, a protrusion 34A is formed on the outer diameter side end of the side surface 30 of the seal 20A toward the outer side in the axial direction of the bearing, and the tip of the protrusion 34A on the outer side of the bearing is the outer diameter side end of the slinger 40A. It is set as the structure which is made into the non-contact proximity | contact state with the flat surface 44A of 48 bearing inner sides, and forms a labyrinth.
An axial lip 32 is formed adjacent to the radially outer side of the seal lip 28, and the tip of the axial lip 32 comes into contact with the flat surface 44A radially inward from the bent convex portion 46A of the slinger 40A. It is configured.

According to the second embodiment, the labyrinth formed by the protruding portion 34A of the seal 20A and the flat surface 44A of the slinger 40A leads from the bearing opening of the outer diameter side end 48 of the slinger 40A to between the seal 20A and the slinger 40A. Intrusion of foreign matter such as water and dust is suppressed. Then, water or dust that has entered the gap between the seal 20A and the slinger 40A from the opening of the bearing at the outer diameter side end 48 of the slinger 40A by the labyrinth formed by the side surface 30 of the seal 20A and the bent convex portion 46A of the slinger 40A. It is possible to prevent foreign matters such as the like from entering the portion where the axial lip 32 contacts the flat surface 44A of the slinger 20A.
Since the axial lip 32 is formed on the inner diameter side of the seal 20A, the diameter of the axial lip 32 is small. Therefore, the contact circle diameter between the axial lip 32 and the flat surface 44A of the slinger 40A is reduced, and the peripheral speed due to relative rotation with the slinger 40A is reduced, so that the torque is reduced and the wear of the axial lip 32 is reduced. Can do. Since heat generated by sliding between the axial lip 32 and the slinger 40A is reduced and the heat resistance of the seal 20A is mitigated, it is possible to use a material having a low heat resistance for the seal 20A.
Since the slinger 40A is more bent than the slinger 40A, the rigidity is further increased. Since the effect of the projection 34A is the same as that of the first embodiment, the description is omitted.
Therefore, according to the second embodiment, it is possible to provide a rolling bearing sealing device in which the sliding torque of the axial lip 32 is reduced to reduce the wear of the seal 20A and the water resistance is improved.

In each of the above embodiments, an example of an outer ring rotation type rolling bearing has been described. However, the present invention can also be applied to an inner ring rotation type rolling bearing sealing device. Even in the case of inner ring rotation, the labyrinth sealing effect and the axial lip is provided on the inner diameter side of the seal to reduce the contact circle diameter between the axial lip and slinger, and the peripheral speed is reduced by the relative rotation of the axial lip and slinger. The effect of reducing torque is exhibited.
In addition, the rolling bearing sealing device according to the present invention can be implemented in various forms within the scope of the concept of the invention.

It is a fragmentary sectional view of the idler pulley which uses the bearing provided with the sealing device for rolling bearings in Example 1. It is an enlarged view of the part regarding the sealing device for rolling bearings in FIG. It is an enlarged view of the part regarding the sealing device for rolling bearings in Example 2. FIG. It is a figure which shows a prior art.

Explanation of symbols

10, 10A Rolling bearing 12 Inner ring 13 Sliding contact surface 14 Outer ring 15 Seal groove 16 Ball 18 Cage 20, 20A Seal 22 Core 24 Covering part 26 Fixing part 28 Seal lip 30 Side face 32 Axial lip 34, 34A Protrusion part 40, 40A Slinger 42 Cylindrical portion 44, 44A Flat surface 46, 46A Bending convex portion 48 Outer diameter side end portion 50 Idler pulley 52 鍔

Claims (2)

A seal fixed to the outer ring, and a slinger arranged coaxially with the inner ring on the outer side of the bearing of the seal, and a gap formed by the seal and the slinger is outside the bearing at the outer diameter side end of the slinger. A rolling bearing sealing device configured to open to
A seal lip configured to be in sliding contact with the inner ring is formed on the inner peripheral edge of the seal, and a radially outer side of the seal is a flat side surface than a position where the seal lip is formed,
The surface of the slinger that faces the seal is a flat surface, and a bent convex portion is formed on the flat surface of the slinger by bending a part thereof in the axial direction and projecting inward of the bearing. The side surface of the seal and the bent convex part of the slinger are in a non-contact proximity state to form a labyrinth,
An axial lip is formed on the side surface of the seal so as to extend outward of the bearing, and the tip of the axial lip is radially inward from the position where the bending projection of the slinger is formed. A sealing device for a rolling bearing, wherein the sealing device is configured to contact a flat surface of the slinger. The rolling bearing sealing device according to claim 1,
A protruding portion is formed at the radially outer end of the side surface of the seal toward the outer side of the bearing, and the protruding portion is brought into a non-contact proximity state with the outer diameter side end portion of the slinger. A rolling bearing sealing device characterized by comprising:

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