JP2007092861A - Sealing device and roll bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a long-life sealing device whose cored bar is hard to become deformed and whose seal lip portion is hard to undergo biased wear and to provide a rolling bearing including the same. <P>SOLUTION: One end of a sealing device 5 is fitted into and fixed to a sealing device fitting groove 51 of an outer race 1. The seal lip portion 24 sliding on a first end face 20 is fixed firmly to a portion opposed to the first end face 20 of an inner race 2 in the cored bar 23 of the sealing device 5. Race grooves 13, 17 of the inner and outer races 1, 2 are sealed from outside by means of the seal lip portion 24. Further, a thrust needle bearing 25 is arranged between a portion opposed to a second end face 21 of the inner race 2 in the cored bar 23 and the second end face 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sealing device, and more particularly to a sealing device suitable for use in a rolling bearing used in a transmission or a crank of a motorcycle or an ATV. Moreover, this invention relates to a rolling bearing provided with the sealing device.

  Conventionally, as a rolling bearing, there is a ball bearing described in JP-A-2002-188651 (Patent Document 1). This ball bearing is used in a situation where high hydraulic pressure acts from the outside of the ball bearing. This ball bearing has an outer ring, an inner ring, a ball, and a sealing device that prevents oil from entering the bearing from the outside. One end portion of the sealing device is fixed to the outer ring, while the other end portion of the sealing device slides with respect to the inner ring. The sealing device includes an annular cored bar and an elastic part fixed to the surface of the cored bar. The portion of the elastic part that covers the end on the inner ring side of the cored bar is a thick, block-shaped seal lip part.

  The ball bearing has a thick and block-like seal lip portion, thereby increasing the rigidity of the elastic portion and increasing the strength of the sealing device, so that oil can enter the bearing from the outside. It is surely prevented.

However, in the conventional ball bearing described above, the core metal is deformed inward in the axial direction by a large hydraulic pressure acting from the outside, and due to this deformation, the tightening margin of the seal lip becomes excessive, and the seal lip portion However, there is a problem that uneven wear tends to occur. For this reason, there exists a problem that a sealing device tends to be damaged.
JP 2002-188651 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a sealing device capable of reliably sealing over a long period of time, and a rolling bearing having the sealing device, in which the core metal is hardly deformed and the seal lip portion is less likely to be unevenly worn.

In order to solve the above problems, the sealing device of the present invention is:
In a sealing device having a fixing part on one side in the radial direction and a seal lip part on the other side in the radial direction and having a cored bar,
An axial movement restricting portion for restricting the axial movement of the cored bar is provided at a portion different from the seal lip portion on the other side in the radial direction.

  According to the present invention, since the axial movement restricting portion for restricting the axial movement of the cored bar is provided at the other side in the radial direction and different from the seal lip portion, it is large from the outside in the axial direction. Even if external pressure is applied, the cored bar is not easily deformed. Therefore, since the occurrence of uneven wear of the seal lip portion due to the deformation of the core metal can be suppressed, the life of the sealing device can be extended.

  Moreover, the sealing apparatus of one Embodiment is a support apparatus in which the said axial direction movement control part has a rolling element.

  According to the embodiment, since the axial movement restricting portion is a support device having a rolling element, deformation of the core metal can be prevented almost completely, and the tightening margin of the seal lip portion is almost changed. There is nothing to do. Therefore, uneven wear of the seal lip portion can be reliably prevented.

  Moreover, the sealing device of one embodiment is a dynamic pressure generating groove in which the axial movement restricting portion generates dynamic pressure for supporting the core metal in the axial direction.

  According to the embodiment, since the axial movement restricting portion is a dynamic pressure generating groove, deformation of the cored bar can be easily and inexpensively suppressed.

  Moreover, the sealing device of one embodiment is a part in which the axial movement restricting portion is provided on the cored bar and is slidably supported in the axial direction and has an oil containing groove.

  According to the embodiment, the axial movement restricting portion is provided on the cored bar and is slidably supported in the axial direction and has an oil containing groove. It can be suppressed at low cost.

  The rolling bearing of the present invention is characterized by including the sealing device of the above invention.

  According to the present invention, since the sealing device of the above invention is provided, oil and foreign matters from the outside can be reliably sealed over a long period of time by the sealing device.

  According to the sealing device of the present invention, since the axial movement restricting portion for restricting the axial movement of the cored bar is provided at a portion different from the seal lip portion on the other radial side, it is large from the outside in the axial direction. Even if external pressure is applied, the cored bar is not easily deformed. Therefore, since the occurrence of uneven wear of the seal lip portion due to the deformation of the core metal can be suppressed, the life of the sealing device can be extended.

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

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

  This ball bearing is incorporated in the transmission of the motorcycle. Although not described in detail, this ball bearing is used in a state where oil having a high hydraulic pressure exists outside one of the ball bearings in the axial direction. The ball bearing includes an outer ring 1, an inner ring 2, a ball 3, and the sealing device 5 according to the first embodiment of the present invention that prevents the oil from entering the bearing.

  The outer peripheral surface of the outer ring 1 is fitted and fixed to a housing (not shown) such as a transmission having the ball bearing. The outer ring 1 has a raceway groove 13 on the inner periphery and a sealing device mounting groove 15 on the inner periphery of one end portion in the axial direction. The inner ring 2 has a raceway groove 17 on the outer periphery. The inner peripheral surface of the inner ring 2 is fitted and fixed to a rotating shaft (not shown). The end surface on one side of the inner ring 2 in the axial direction has a two-stage structure. Specifically, the end surface of the inner ring 2 on one side in the axial direction is connected to the shoulder of the raceway groove 17 of the inner ring 2 and is a slope that extends radially inward of the inner ring 2 and outward in the axial direction. The first end surface 20 and the second outer end of the first end surface 20 in the axial direction are connected to each other via a cylindrical surface extending in the axial direction, and the second end surface expands substantially inward in the radial direction. It is comprised with the end surface 21. FIG. A plurality of balls 3 are arranged between the raceway groove 13 of the outer ring 1 and the raceway groove 17 of the inner ring 2 while being held by a cage 18 with a certain interval in the circumferential direction. .

  The sealing device 5 includes a metal core 23, a rubber seal lip portion 24, and a thrust needle bearing 25 as an example of a support device.

  The core metal 23 extends in a substantially radial direction from the sealing device mounting groove 15 of the outer ring 1 to the inner peripheral side of the inner ring 2. One end of the core bar 23 in the radial direction is bent in a ring shape outward in the axial direction. In other words, the radially outer end of the core bar 23 is a curled head. By inserting this curled head into the sealing device mounting groove 15, the sealing device 5 is fitted and fixed to the outer ring 1. The curl type head is a fixed portion.

  The seal lip portion 24 is fixed to a location facing the first end face 20 on the inner end face in the axial direction of the cored bar 23. The seal lip portion 24 is in contact with the first end surface 20 that is a slope with a predetermined tightening allowance. The seal lip portion 24 slides on the first end surface 20 to seal the inside of the bearing with respect to the outside.

  The thrust needle bearing 25 includes a cage 30 and a needle 31 as an example of a rolling element housed in a pocket of the cage 30. The thrust needle bearing 25 is disposed between the second end surface 21 of the inner ring 2 and a portion of the core metal 23 facing the second end surface 21. The thrust needle bearing 25 supports the portion of the core metal 23 in the axial direction so that the core metal 23 is not deformed by a large hydraulic pressure from the outside.

  According to the sealing device 5 of the first embodiment, the axial direction of the sealing device 5 includes the thrust needle bearing 25 that supports the portion of the core metal 23 in the axial direction of the outer ring 1 (the axial direction of the inner ring 2). Even if a large external pressure is applied to the outer end surface of the metal core 23, the core bar 23 is not easily deformed. Therefore, since the occurrence of uneven wear of the seal lip portion 24 due to the deformation of the core metal 23 can be suppressed, the life of the sealing device 5 can be extended.

  Further, according to the sealing device 5 of the first embodiment, since the seal lip portion 25 slides on the first end surface 20, the seal lip portion is lifted in the radial direction by external hydraulic pressure. And the oil can be reliably sealed.

  Further, according to the sealing device 5 of the first embodiment, since the axial movement restricting portion is the needle bearing 25 having the needle 31 as the rolling element, the deformation of the cored bar 23 can be reliably prevented. Further, since the axial movement restricting portion is the needle bearing 25 having the needle 31, it is possible to accurately adjust the space between the portion and the second end surface 21 of the inner ring 2 at a predetermined interval. Therefore, the space between the portion and the second end surface 21 of the inner ring 2 is reduced, and the tightening allowance of the seal lip portion 24 is not excessive, so that uneven wear of the seal lip portion 24 can be reliably prevented. In addition, the space between the above-described portion and the second end surface 21 of the inner ring 2 is increased, so that the sealing performance of the seal lip portion 24 is not deteriorated, and external oil can be reliably prevented from entering the ball bearing. it can.

  Moreover, since the ball bearing of the said embodiment is equipped with the sealing device 5 of this invention, the inside of a bearing can be reliably sealed over the long term with respect to the exterior of a bearing.

  In the sealing device 5 of the first embodiment, the thrust needle bearing 25 including the needle 31 and the retainer 30 is adopted as the support device. However, the sealing device of the present invention is provided in the needle and the retainer as the support device. In addition, a thrust needle bearing having an outer diameter flange, a thrust needle bearing having an inner diameter flange in addition to the needle and the cage, or a thrust needle bearing having two race rings in addition to the needle and the cage may be employed. . Moreover, the sealing device of the present invention may employ a thrust ball bearing in which the rolling elements are balls or a thrust roller bearing in which the rolling elements are rollers.

  In the sealing device 5 of the first embodiment, the fixing portion of the sealing device 5 fitted in the sealing device mounting groove 15 of the outer ring 2 is a curl type head formed by bending the core metal 23 into a ring shape. However, in the present invention, the fixing portion in the sealing device fitted in the sealing device mounting groove of the outer ring is not a curled head of the core metal, such as a rubber head in which rubber is fixed to the core metal. It may be a head.

  Further, in the sealing device 5 of the first embodiment, the seal lip 24 slides on the axial end face of the inner ring 2 to seal the inside of the bearing from the outside. Then, the seal lip portion may be configured to seal the inside of the bearing from the outside by sliding on the outer peripheral surface of the inner ring.

  In the sealing device 5 of the first embodiment, one end of the sealing device 5 is fixed to the outer ring, and the seal lip formed on the other end of the sealing device 5 is slid on the inner ring. However, in the present invention, one end portion of the sealing device may be fixed to the inner ring, and a seal lip portion formed at the other end portion of the sealing device may be slid on the outer ring.

  Moreover, in the said embodiment, although the sealing device 5 of this invention was used as a sealing device of a ball bearing, even if it uses a sealing device of this invention as a sealing device of rolling bearings other than ball bearings, such as a roller bearing. Of course it is good.

  FIG. 2 is a partial sectional view in the axial direction of a ball bearing which is a second embodiment of the rolling bearing of the present invention. This ball bearing has the sealing device 35 of the second embodiment. The ball bearing of the second embodiment differs from the ball bearing of the first embodiment only in that the shape of the inner ring 32 is different and the sealing device 35 is different.

  In the ball bearing of the second embodiment, the same components as those of the ball bearing of the first embodiment are denoted by the same reference numerals and the description thereof is omitted. Further, in the sealing device 35 of the second embodiment, the description of the operations and effects common to the sealing device 5 of the first embodiment is omitted, and only the configuration different from the sealing device 5 of the first embodiment is omitted. I will explain.

  The inner ring 32 of this ball bearing is connected to the outer peripheral surface, and is extended to the first end surface 40 that extends in a substantially radial direction, and is connected to the first end surface 40 via a cylindrical surface, and has axially outward and radial contents. And a second end face 41 that is an extending slope. An annular seal lip portion 44 is fixed to a portion of the core bar 43 of the sealing device 35 that faces the second end surface 41. The seal lip portion 44 slides on the second end surface 41 and seals (seals) the inside of the bearing with respect to the outside. Further, a thrust needle bearing 45 as an example of a holding portion is disposed between the first end surface 40 and a portion of the cored bar 43 facing the first end surface 40.

  FIG. 3 is a partial sectional view in the axial direction of a ball bearing which is a third embodiment of the rolling bearing of the present invention. This ball bearing has the sealing device 55 of the third embodiment. This ball bearing is different from the ball bearing of the first embodiment only in that the shape of the inner ring 52 is different and the sealing device 55 is different.

  In the sealing device 55 of the third embodiment, the description of the operations and effects common to the sealing device 5 of the first embodiment will be omitted, and the configurations and operations different from the sealing device 5 of the first embodiment will be omitted. I will only explain.

  The inner ring 52 is connected to an outer peripheral surface 56 that is continuous with a raceway groove (not shown), a first end surface 57 that extends in a substantially radial direction, and is connected to the first end surface 57 via a cylindrical surface. And a second end face 58 extending in a substantially radial direction. Further, the portion of the core metal 53 facing the first end surface 57 is curved in a substantially U-shaped cross section, and the axial distance between the radially outer end of the first end surface 57 and the core metal 53 is The axial distance between the substantially central portion of the first end surface 57 in the radial direction and the cored bar 53 is larger.

  A first seal lip 61 is fixed to a portion of the first end surface 57 facing the radially outer end, and a portion of the core metal 53 facing the second end surface 58 has a second seal. The lip 62 is fixed. The first seal lip portion 61 seals the inside of the bearing from the outside by sliding on the radially outer end portion of the first end surface 57, and the second seal lip portion 62 is on the first end surface 58. By sliding, the inside of the bearing is sealed from the outside. Further, between the substantially central portion of the first end surface 57 in the radial direction and the portion of the cored bar 53 facing the substantially central portion (the interval between this is the other side in the radial direction of the sealing device and the seal lip portion 61, A thrust needle bearing 59 is disposed at a portion different from 62).

  According to the sealing device 55 of the third embodiment, the seal device 55 has two sealing lip portions 61 and 62 and seals the inside of the bearing to the outside at two different locations. Can be improved.

  FIG. 4 is a partial sectional view in the axial direction of a ball bearing which is a fourth embodiment of the rolling bearing of the present invention. This ball bearing has the sealing device 75 of the fourth embodiment. This ball bearing differs from the ball bearing of the first embodiment only in that the shape of the inner ring 72 is different and the sealing device 75 is different. In the sealing device 75 of the fourth embodiment, the description of the operations and effects common to the sealing device 5 of the first embodiment will be omitted, and the configuration, operation and effects different from those of the sealing device 5 of the first embodiment will be omitted. Only the modification will be described.

  The inner ring 72 is connected to an outer peripheral surface 76 that is continuous with a raceway groove (not shown), a first end surface 77 that extends in a substantially radial direction, and is connected to the first end surface 77 via a cylindrical surface. And a second end face 78 extending in a substantially radial direction.

  A seal lip portion 71 is fixed to a portion of the core bar 73 of the sealing device 75 that faces the first end surface 77. The seal lip 71 slides on the first end surface 77 to seal the raceway groove and the like in the bearing from the outside of the bearing.

  Further, a herringbone type dynamic pressure generating groove as an example of the axial movement restricting portion is formed in a portion 79 of the core metal 73 facing the first end surface 78.

  FIG. 5 is a partial plan view of a portion 79 of the cored bar 52 that faces the second end surface 78.

  A portion 79 of the core metal 52 facing the second end surface 78 is a portion surrounded by two circles having the same center and different radii. The dynamic pressure generating groove 80 has a substantially square shape. A plurality of the dynamic pressure generating grooves 80 are formed at substantially equal intervals over the entire circumference in the circumferential direction of the portion 79 indicated by the arrow a. The dynamic pressure generating groove 80 generates dynamic pressure due to the relative rotational movement in the circumferential direction with respect to the second end surface 78 of the portion 79.

  According to the sealing device 75 of the fourth embodiment, since the axial movement restricting portion is formed by forming the dynamic pressure generating groove 80 in the portion 79, the deformation of the core metal 73 can be easily and inexpensively. Can be suppressed.

  In the sealing device 75 of the fourth embodiment, the herringbone type dynamic pressure generating groove 80 is formed in the portion 79 of the core metal 52 facing the second end surface 78. In the present invention, A dynamic pressure generating groove other than the herringbone type dynamic pressure generating groove, such as a spiral type dynamic pressure generating groove, may be formed in a portion of the core metal facing the end face in the axial direction of the race.

  Moreover, in the said 4th Embodiment, although the dynamic pressure generation groove | channel 80 was formed in the site | part 79 facing the 2nd end surface 78 in the said metal core 52, the end surface of the axial direction of the track ring in the metal core of a sealing device. If the dynamic pressure generating groove is formed in at least one of the portion facing the core and the portion facing the cored bar on the axial end surface of the raceway ring, Of course, similar effects can be obtained. In this case, at least one of the portion facing the axial end surface of the raceway ring in the core metal of the sealing device and the portion facing the core metal on the axial end surface of the raceway ring is the sealing device. Of course, the dynamic pressure generating groove corresponds to a portion different from the seal lip portion on the other side in the radial direction.

  FIG. 6 is a partial sectional view in the axial direction of a ball bearing which is a fifth embodiment of the rolling bearing of the present invention. This ball bearing has the sealing device 95 of the fifth embodiment. This ball bearing is different from the ball bearing of the first embodiment only in that the sealing device 95 is different. In the sealing device 95 of the fifth embodiment, the description of the operations and effects common to the sealing device 5 of the first embodiment will be omitted, and the configuration, operation and effects different from those of the sealing device 5 of the first embodiment will be omitted. Only the modification will be described.

  The inner ring 92 of the ball bearing includes an outer peripheral surface 96 that is continuous with the raceway groove, a first end surface 97 that is continuous with the outer peripheral surface 96 and is a slope that extends radially inward and outward in the axial direction. The first end surface 97 is constituted by a second end surface 98 which is continuous with the outer end in the axial direction through a cylindrical surface extending in the axial direction and which expands inward in the substantially radial direction.

  The sealing device 95 includes a core metal 93, a seal lip 91, and an annular member 100 made of a brass alloy. The seal lip portion 91 is fixed to a location facing the first end surface 97 on the inner end surface of the cored bar 93 in the axial direction. The seal lip portion 91 is in contact with the first end surface 97, which is an inclined surface, with a predetermined tightening allowance. The seal lip 91 slides on the first end surface 97 to seal the inside of the bearing with respect to the outside.

  The annular member 100 is welded to the surface of the core metal 93 that faces the second end surface 98. As shown in FIG. 6, the annular member 100 is in contact with the second end face 98. An oil containing groove 101 is formed on the surface of the annular member 100 on the second end face 98 side so as to extend over the entire circumference in the circumferential direction of the annular member 100. When the core metal 93 rotates relative to the inner ring 92 in the circumferential direction, the oil stored in the oil storage groove 101 comes out of the oil storage groove 101 and is between the second end surface 98 and the annular member 100. An oil film is formed on the surface. A portion of the annular member 100 that is in contact with the second end surface 98 is slidably supported in the axial direction. A portion of the annular member 100 that is in contact with the second end face 98 is an axial movement restricting portion.

  FIG. 7 is a view showing the surface of the annular member 100 on the second end face 98 side.

  As shown in FIG. 7, the surface on the second end face 98 side of the annular member 100 has a shape sandwiched between two circles having the same center and different radii. Further, the oil containing groove 101 includes an annular first groove 103 extending in the circumferential direction of the annular member 100 shown by b in FIG. 7, and a plurality of substantially identical second grooves extending radially inward from the annular groove 103. The groove 105 is constituted. As shown in FIG. 7, the second grooves 105 are formed at substantially equal intervals in the circumferential direction. Further, the second groove 105 is open in a space located inward in the radial direction with respect to the annular member 100.

  According to the sealing device 95 of the fifth embodiment, the axial movement restricting portion is a portion that is in contact with the second end surface 98 of the annular member 100 having the oil containing groove 101, so that the core bar 93 is deformed. It can be easily and inexpensively controlled.

  In the fifth embodiment, the oil containing groove 101 is formed in the annular member 100 welded to the surface of the core metal 93 facing the second end face 98. However, in the present invention, the oil containing groove is sealed in the sealing device. You may form directly in the part which opposes the end surface of the axial direction of a track ring in this metal core. In this case, the portion of the race that contacts the portion of the core metal in which the oil receiving groove is formed is welded to the main portion of the race and is made of a material made of a material used for a slide bearing such as a brass alloy. It is preferable that the surface of the core metal side end surface portion is a surface of the core metal side (in this case, the raceway ring (inner ring or outer ring) is composed of a main body portion and a core metal side end surface portion).

  Moreover, in the said 5th Embodiment, although the oil accommodation groove | channel 101 was formed in the annular member 100 welded to the part 99 facing the 2nd end surface 98 in the said metal core 93, the bearing ring in the metal core of a sealing device. An oil containing groove is formed in at least one of a portion facing the end surface in the axial direction or a member fixed to the portion and a portion in contact with the cored bar on the end surface in the axial direction of the bearing ring. Just do it. In this case, needless to say, the portion including the oil containing groove and the portion in contact with the other member is the axial movement restricting portion.

  Although not described in the first to fifth embodiments, it goes without saying that the sealing device of the present invention may have a plurality of support devices, a plurality of dynamic pressure generation grooves, or a plurality of oil storage grooves. Yes. It goes without saying that the sealing device of the present invention may have two or more of the support device, the dynamic pressure generating groove, and the oil containing groove.

It is sectional drawing of the axial direction of the ball bearing of 1st Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the axial direction of the ball bearing which is 2nd Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the axial direction of the ball bearing which is 3rd Embodiment of the rolling bearing of this invention. It is a fragmentary sectional view of the axial direction of the ball bearing which is 4th Embodiment of the rolling bearing of this invention. It is a fragmentary top view of the part facing the 2nd end surface in the metal core of the sealing device of 4th Embodiment. It is a fragmentary sectional view of the axial direction of the ball bearing which is 5th Embodiment of the rolling bearing of this invention. It is a figure which shows the surface by the side of the 2nd end surface of the annular member which the sealing device of 5th Embodiment has.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Outer ring 2,32,52,72,92 Inner ring 3 Ball 5,35,55,75,95 Sealing device 20,40,57,77,97 First end surface 21,41,58,78,98 Second end surface 23 , 43, 73 Core 24, 44, 61, 62, 71, 91 Seal lip 25, 45, 59 Needle bearing 31 Needle 80 Dynamic pressure generating groove 100 Annular member 101 Oil containing groove

Claims (5)

In a sealing device having a fixing part on one side in the radial direction and a seal lip part on the other side in the radial direction and having a cored bar,
A sealing device comprising an axial movement restricting portion for restricting the axial movement of the cored bar at a portion different from the seal lip portion on the other radial side. The sealing device according to claim 1,
The sealing device according to claim 1, wherein the axial movement restricting portion is a support device having a rolling element. The sealing device according to claim 1,
The sealing device according to claim 1, wherein the axial movement restricting portion is a dynamic pressure generating groove for generating a dynamic pressure for supporting the core metal in the axial direction. The sealing device according to claim 1,
The said axial direction movement control part is a part which has an oil storage groove | channel while being provided in the said metal core and slidingly supported in the said axial direction.   A rolling bearing comprising the sealing device according to any one of claims 1 to 4.

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