JP6381232B2 - Rolling bearing - Google Patents

Description

The present invention relates to a rolling bearing rising.

  A roll of a continuous casting machine for rolling a metal material such as iron can be freely rotated through a cylindrical portion called a roll neck provided coaxially at both axial end portions thereof, for example, via a double row tapered roller bearing. Has a supported structure. The bearing used in such a continuous casting machine facility is usually an unsealed type without a seal, and grease is always supplied to the bearing by a continuous greasing mechanism.

  Moreover, as a bearing used for continuous casting machine equipment, there is also a sealed type provided with a sealing device to prevent rolling water or cooling water from entering the inside of the bearing. As such a seal device, there is known a device having a contact seal structure that shields a bearing lip portion that seals the bearing inner space between the inner ring and the outer ring and that contacts the contact surface by shielding the axial end opening of the bearing. (For example, refer to Patent Document 1). In the sealing device of Patent Document 1, a metal ring is embedded in the base end portion of the seal lip portion, and the base end portion is reinforced by the metal ring.

JP 2003-227522 A

  By the way, since the continuous casting equipment is used in an environment with water vapor and oxide scale, grease is likely to be contaminated by water and scale, and if contaminated grease is supplied into the bearing, the bearing may be worn or damaged. Connected. Furthermore, since grease for continuous lubrication requires a usage of approximately 30 to 70 tons per year per continuous casting machine, the amount of grease waste is enormous and there is a risk of environmental pollution. Processing of objects is also complicated and expensive. Thus, the development of bearings that reduce the amount of grease used and have a low environmental load is an issue.

  Therefore, it is conceivable to use a sealed bearing having a sealing device as in Patent Document 1, but in this sealing device, when the shaft is eccentric or inclined, the contact state with the contact surface changes, A portion that hits strongly and a portion that hits weakly occur. And in the part which is contact | abutting strongly with a contact surface, it will become easy to produce a damage. On the other hand, at the portion that is weakly in contact with the contact surface, the interference with the contact surface is weakened, so that the lubricant inside the bearing is likely to leak and foreign matter can easily enter from the outside, causing early bearing damage. There is a risk of inviting.

Also, when fatigue (plastic deformation or sag) occurs in the seal lip part made of rubber material,
Even when the internal temperature of the bearing rises to about 70 ° C. to 80 ° C. due to the high temperature operation (about 700 to 1500 ° C.) of the continuous casting equipment, the seal lip portion and the contact surface May open, causing leakage of the lubricant in the bearing and entry of foreign matter from the outside.

The present invention has been made in view of the above-described problems, and can maintain the sealing performance of the bearing well even when the shaft is eccentric or inclined, and the pressure resistance of the seal lip portion ( It is an object of the present invention to provide a rolling bearing capable of improving internal pressure resistance and external pressure resistance and capable of suppressing the occurrence of fatigue.

The above object of the present invention can be achieved by the following constitution.
(1) It is formed in a substantially annular shape so as to close the axial end opening of the space existing between the outer peripheral surface of the inner ring and the inner peripheral surface of the outer ring or the spherical seat disposed radially outside the outer ring. A rolling bearing provided with a sealing device for the rolling bearing ,
The rolling bearing sealing device includes a substantially ring-shaped cored bar, an elastic body fixed to the cored bar,
With
The cored bar is fixed to the inner peripheral surface of the outer ring or the spherical seat, and is arranged on the inner side in the axial direction than the first cored bar extending radially inward and the radially inner end of the first cored bar, Divided into a second mandrel extending radially inward,
The elastic body includes a connecting portion that connects a radially inner end portion of the first cored bar and a radially outer end portion of the second cored bar, a seal lip portion fixed to the second cored bar, Have
The seal lip portion includes a lip waist portion fixed to the second core metal, and a lip tip portion that is continuous from the lip waist portion and whose radially inner end portion is in sliding contact with the outer peripheral surface of the inner ring,
On the outer peripheral surface of the lip tip portion, a spring that urges the lip tip portion toward the outer peripheral surface of the inner ring is disposed,
The radial thickness between the radially inner end of the lip tip and the radially inner end of the spring is 1% or more of the diameter of the outer peripheral surface of the inner ring,
Inner diameter of the second core metal is rather smaller than the diameter of the outer peripheral surface of a portion radial thickness of the lip waist is minimized,
The rolling bearing according to claim 1, wherein a radial thickness of the lip waist portion between the spring and the second metal core is 1% or more of a diameter of an outer peripheral surface of the inner ring at a minimum position .
( 2 ) The radially inner end of the lip tip is in sliding contact with the outer peripheral surface of the inner ring with an interference,
2 times the value of White said tightening is rolling bearing according to (1) said at inner ring of more than 1% of the diameter of the outer peripheral surface.

According to the rolling bearing of the present invention, the cored bar is fixed to the inner peripheral surface of the outer ring or the spherical seat and extends radially inward, and axially inward from the radially inner end of the first cored bar. The elastic core is connected to connect the radially inner end of the first core and the radially outer end of the second core. And a seal lip portion that is fixed to the second core metal and in which the radially inner end portion of the lip tip portion is in sliding contact with the outer peripheral surface of the inner ring. Therefore, even when eccentricity or inclination of the shaft occurs, it is possible to maintain the contact between the seal lip portion and the outer peripheral surface of the inner ring by the connecting portion of the elastic body following the eccentricity or inclination of the shaft. It is. Further, since the seal lip portion is fixed to the second cored bar, the interference with the outer peripheral surface of the inner ring and the tightening force can be kept constant, and good sealing performance can be exhibited.
Further, the thickness of the lip tip is such that the radial thickness between the radially inner end of the lip tip and the radially inner end of the spring is 1% or more of the diameter of the outer peripheral surface of the inner ring. Since the pressure resistance (internal pressure resistance and external pressure resistance) of the seal lip is improved, the inner ring increases even if the internal pressure increases due to the temperature rise of the bearing or the external pressure of the bearing increases. It is possible to maintain the tightening force with respect to the outer peripheral surface, and it is possible to suppress the occurrence of fatigue.

  In addition, when the thickness of the lip waist portion is appropriately set so that the radial thickness of the lip waist portion is 1% or more of the diameter of the outer peripheral surface of the inner ring at the minimum position, the pressure resistance of the seal lip portion ( (Internal pressure resistance and external pressure resistance) are further improved, and even when the internal pressure rises due to the temperature rise of the bearing or when the external pressure of the bearing rises, it is possible to further maintain the tightening force against the outer peripheral surface of the inner ring In addition, it is possible to further suppress the occurrence of fatigue.

  Also, the radially inner end of the lip tip is brought into sliding contact with the outer peripheral surface of the inner ring with an interference, and the double value of the interference is 1% or more of the diameter of the outer peripheral surface of the inner ring. The pressure resistance (internal pressure resistance, external pressure resistance) of the seal lip is further improved, and even if the internal pressure increases due to the temperature rise of the bearing or the external pressure of the bearing increases Further, it is possible to further maintain the tightening force with respect to the outer circumferential surface of the inner ring and to further suppress the occurrence of fatigue.

It is principal part sectional drawing of the self-aligning roller bearing which concerns on embodiment. It is principal part sectional drawing of an oil seal. It is principal part sectional drawing of the roll of a continuous casting machine. It is sectional drawing of a pressure | voltage resistant test apparatus. It is principal part sectional drawing of a double row tapered roller bearing with a spherical seat. It is principal part sectional drawing of a cylindrical roller bearing with a spherical seat. It is principal part sectional drawing of a double row tapered roller bearing with a spherical seat. It is principal part sectional drawing of a cylindrical roller bearing with a spherical seat.

  Hereinafter, a rolling bearing sealing device according to an embodiment of the present invention will be described in detail with reference to the drawings.

  As shown in FIG. 1, the self-aligning roller bearing 10 according to the present embodiment includes an outer ring 11 having a spherical outer ring raceway groove 11a formed on the inner peripheral surface, and a spherical inner ring raceway groove 12a formed on the outer peripheral surface. A plurality of rolling wheels are rotatably supported by the inner ring 12 formed in two rows and the cage 13 and are arranged in two rows between the outer ring raceway groove 11a and the inner ring raceway groove 12a. A pair of barrel-shaped rollers 14 that are moving bodies and a pair of seals that seals the inside of the bearing, respectively, so as to close the openings in both axial ends of the space existing between the inner peripheral surface of the outer ring 11 and the outer peripheral surface of the inner ring 12. And an oil seal 20 as a rolling bearing sealing device.

A through hole 15 that penetrates from the outer peripheral surface to the inner peripheral surface, can supply the lubricant to the bearing space, and can vent the air is formed in the axially intermediate portion of the outer ring 11. In addition, a female screw part (not shown) may be provided in the through-hole 15 and a plug for sealing the bearing space may be screwed into the female screw part. Further, as long as the lubricant is sealed in the bearing space, the through hole 15 may not be provided. Here, a lubricant sealed in the bearing space, 70mm ² / s~500mm ² Viscosity high viscosity lubricating oil which is 300mm ² / ^{s~500mm 2} / s at 40 ° C., or kinematic viscosity at 40 ° C. Grease having excellent heat resistance and wear resistance using a base oil and urea compound as / s as a thickener.

  Referring also to FIG. 2, the oil seal 20 is formed in a substantially annular shape as a whole, and is fixed to the core 30 fixed to the inner peripheral surface of the outer ring 11 and the axially outer surface of the core 30. And an elastic body 40 made of an elastic material such as rubber.

  The core metal 30 is press-fitted and fixed in a groove 11b formed at the axially outer end of the inner peripheral surface of the outer ring 11, and has a substantially L-shaped cross section that extends radially inward (hereinafter, the cross section refers to a circumferential cross section). A first cored bar 32), a second cored bar 34 that is arranged on the inner side in the axial direction than the radially inner end 32a of the first cored bar 32 and extends inward in the radial direction, It is divided into

  The elastic body 40 includes a first extending portion 41 having a substantially L-shaped cross section that is fixed to the outer surface in the axial direction of the first metal core 32 and a substantially straight line that is fixed to the outer surface in the axial direction of the second metal core 34. The second extending portion 42 having the shape, the first extending portion 41 and the second extending portion 42 are continuous, and the radially inner end 32a of the first core metal 32 and the radially outer side of the second core metal 34 are connected. And a connection portion 43 for connecting the end portion 34a. Here, since the radially inner end portion 32a of the first core metal 32 is located radially outside the radially outer end portion 34a of the second core metal 34, the connecting portion 43 of the elastic body 40 is The cross section has a substantially linear shape that is slightly inclined radially inward as it goes inward in the axial direction.

  The elastic body 40 continuously extends from the radially inner end portion of the second extending portion 42 to the outer side in the axial direction, and is fixed to the radially inner end portion 34 b of the second core metal 34 on the outer side in the axial direction. The lip waist portion 44a and the lip waist portion 44a are continuous from the lip waist portion 44a, and the radially inner end portion 44c thereof slides elastically with an interference G with respect to the groove portion 12b formed at the outer end surface of the inner ring 12 in the axial direction. A seal lip portion 44 having a lip tip portion 44b in contact therewith. Here, the interference G is the diameter (outer diameter) of the outer peripheral surface (groove portion 12b) of the inner ring 12 on which the seal lip portion 44 slides, and the diameter of the radially inner end portion 44c of the lip tip portion 44b. (Inner diameter) and the difference. Since the seal lip portion 44 needs to be slidably contacted with the groove portion 12b of the inner ring 12 to securely seal between the outer ring 11 and the inner ring 12, a spring 50 is attached to the outer peripheral surface 44d of the seal lip portion 44. The seal lip 44 is urged toward the groove 12b of the inner ring 12 by the elastic force of the spring 50.

  Furthermore, the elastic body 40 has a bumper lip portion 45 that is fixed to the radially inner end portion 34 b of the second core metal 34 and that is located on the axially inner side of the seal lip portion 44. The bumper lip portion 45 is formed such that its radially inner end portion 45a is positioned radially outward from the radially inner end portion 44c of the lip tip portion 44b, and is not between the groove portion 12b of the inner ring 12. Acts as an auxiliary lip that forms a seal of contact.

  Here, in the oil seal 20 of the present embodiment, in order to improve the pressure resistance (internal pressure resistance, external pressure resistance) of the seal lip portion 44 and suppress the occurrence of fatigue, the lip waist portion 44a and the lip tip end. The radial thickness of the portion 44b is set to an appropriate value. More specifically, the diameter (outer diameter) of the outer peripheral surface (groove portion 12b) of the inner ring 12 is 1 at the position where the radial thickness of the lip waist portion 44a is minimized (indicated by F in FIG. 2). % Is set to be at least%. The radial thickness E between the radial inner end 44c of the lip tip 44b and the radial inner end 50a of the spring 50 is the diameter (outer diameter) of the outer peripheral surface (groove 12b) of the inner ring 12. Is set to be 1% or more. Furthermore, the lip tip 44b is set so that the double value of the interference G with respect to the groove 12b of the inner ring 12 is 1% or more of the diameter (outer diameter) of the outer peripheral surface (groove 12b) of the inner ring 12. .

  The self-aligning roller bearing 10 including the oil seal 20 configured as described above is used, for example, at a location where the rotational speed is very slow (several revolutions per minute) such as continuous casting equipment, and has good sealing performance. Demonstrated, the encapsulated lubricant is maintained for a long life. More specifically, as shown in FIG. 3, the self-aligning roller bearing 10 is continuously cast so that the inner ring 12 is fitted on the roll neck portion 70 a of the roll 70 and the outer ring 11 is fitted on the housing 71. Built into the machine.

  A shaft side chock seal 72 is arranged between the shaft side end portion of the housing 71 (left side end portion in FIG. 3) and the shaft side end portion of the roll neck portion 70a in the radial direction. A pair of roll side chock seals 73 is arranged between the radial direction between the right side end portion in FIG. 3 and the roll side end portion of the roll neck portion 70a. And the space between the roll neck portion 70a is sealed.

  Inside the housing 71, a grease supply hole 74 is provided in the axial direction from the axial end surface, and the grease supply hole 74 is formed in a space 75 formed between the pair of roll side chock seals 73 in the axial direction. It is connected and has a substantially L-shaped cross section. Further, the housing 71 is provided with a grease discharge hole 76 penetrating from the space 75 to the outer peripheral surface of the housing 71.

  Here, as indicated by an arrow in FIG. 3, the grease is supplied to the space 75 through the grease supply hole 74 and is used for lubricating rotating members such as the roll neck portion 70 a of the roll 70. It passes through the discharge hole 76 and is discharged to the outside of the housing 71.

  Here, it is desirable that the grease supplied through the grease supply hole 74 is sealed in the space 75 by the roll side chock seal 73. However, if the seal of the roll side chock seal 73 is incomplete, automatic adjustment is performed. It may enter the gap 77 on the side of the center roller bearing 10. At this time, since the grease in the gap 77 applies an external pressure to the self-aligning roller bearing 10, when the external pressure becomes larger than the internal pressure in the bearing, the grease of the inner ring 12 is against the oil seal 20. A force acts in a direction in which a gap is generated between the outer peripheral surface.

  However, according to the oil seal 20 of the present embodiment, the thicknesses are appropriately set so that the radial thicknesses E and F and the interference G are 1% or more of the diameter of the outer peripheral surface of the inner ring 12. The pressure resistance (external pressure resistance) of the seal lip 44 is improved, and even when the pressure outside the bearing rises, it is possible to maintain the tightening force against the outer peripheral surface of the inner ring 12 and suppress the occurrence of fatigue. Is possible. Therefore, it is possible to prevent the ingress of grease, water, foreign matter, etc. from the outside of the bearing.

  Even when the pressure inside the bearing rises due to the temperature rise of the bearing and the internal pressure becomes larger than the external pressure, a gap is generated between the oil seal 20 and the outer peripheral surface of the inner ring 12. Force acts. However, as described above, according to the oil seal 20 of the present embodiment, the radial thicknesses E and F and the interference G are appropriately set so that the diameter of the outer peripheral surface of the inner ring 12 is 1% or more. Therefore, the pressure resistance (internal pressure resistance) of the seal lip portion 44 is improved, and even when the pressure inside the bearing rises, it is possible to maintain the pressing force against the outer peripheral surface of the inner ring 12 and fatigue. Can be suppressed. Therefore, it is possible to prevent the lubricant enclosed in the bearing internal space from leaking to the outside of the bearing, and it is possible to maintain the lubricant with a long life.

(Example)
Here, the bearing internal pressure when the bearing temperature rises from 0 ° C. (minimum temperature T0) to 80 ° C. (maximum temperature T1) due to rotation or the like is calculated. Assuming that the pressure when the air temperature is T0 = 273.15 [K] is p0 and the pressure when T1 = 273.15 + 80 = 353.15 [K] is p1, p0 / T0 according to Charles Boyle's law = P1 / T1, that is, p1 / p0 = T1 / T0 = 1.3. That is, the pressure p1 at T1 = 80 [° C.] is 1.3 times the pressure p0 at T0 = 0 [° C.]. When p0 is an atmospheric pressure, the pressure difference p1-p0 is a relative pressure at the temperature T1, and when converted to a pressure in Pa, p1-p0 = 1.01325 × 10 ⁵ × (1.3-1) = 3.04 × 10 ⁴ [Pa] = 30.4 [kPa]. Therefore, the bearing internal pressure when the bearing temperature rises from 0 ° C. to 80 ° C. is 30.4 kPa.

  As described above, the pressure resistance (internal pressure resistance) of the seal lip portion 44 of the oil seal 20 is such that even when the bearing internal pressure is larger than 30 kPa, the tension force on the outer peripheral surface of the inner ring 12 is maintained. desirable.

  Then, the result of having tested using the pressure resistance test apparatus about the pressure resistance (internal pressure resistance) of the seal lip part 44 of the oil seal 20 of this embodiment is shown below.

  As shown in FIG. 4, the pressure test device 60 includes an outer ring equivalent member 11A and an inner ring equivalent member 12A, and the oil seal 20 is fixed to the inner peripheral surface of the outer ring equivalent member 11A, and the lip tip of the seal lip portion 44 is provided. The radially inner end 44c of the portion 44b contacts the outer peripheral surface of the inner ring equivalent member 12A.

  In addition, the pressure test apparatus 60 includes a first pressure chamber 62 and a second pressure chamber that can change the internal pressure on the axially inner side (left side in FIG. 4) and the axially outer side (right side in FIG. 4) of the oil seal 20, respectively. A pressure chamber 64 is provided. The first pressure chamber 62 corresponds to a bearing internal space, and the pressure is expressed as an internal pressure P1. The second pressure chamber 64 corresponds to the outside of the bearing, and the pressure is expressed as an external pressure P2.

  In this test, the oil seal 20 has a lip diameter (diameter of the radially inner end 44c of the seal lip portion 44) of φ185 (mm), and the radial thicknesses E and F described above (see FIG. 2). However, those having a diameter (outer diameter) of 1% or more of the outer peripheral surface (groove portion 12b) of the inner ring 12 and those having a diameter of less than 1% were used.

  The external pressure P2 of the second pressure chamber 64 is maintained at atmospheric pressure, and the internal pressure P1 of the first pressure chamber 62 is maintained between the seal lip portion 44 and the outer peripheral surface of the inner ring equivalent member 12A until air leakage occurs. The pressure was increased every 10 kPa (maintained for 30 minutes after the increase), and the pressure until air leaked was tested. The results of the test are shown in Table 1.

  Thus, when both the radial thicknesses E and F are less than 1%, the pressure resistance (internal pressure resistance) of the seal lip portion 44 is poor, and the internal pressure P1 is larger than 30 kPa, that is, the internal pressure P1 is 40 kPa. If this is the case, air leakage will occur. On the other hand, when the radial thicknesses E and F are both 1% or more as in the above-described embodiment, air leakage does not occur even when the internal pressure P1 is 40 kPa, and the pressure resistance (resistance to It can be seen that the internal pressure property is good.

As described above, according to the oil seal 20 of the present embodiment, the core metal 30 is fixed to the inner peripheral surface of the outer ring 11 and extends radially inward, and the diameter of the first core metal 32. A second cored bar 34 that is disposed on the inner side in the axial direction than the inner end 32a and extends inward in the radial direction, and the elastic body 40 includes a second inner end 32a of the first cored bar 32 and a second cored bar 34a. A connecting portion 43 that connects the radially outer end 34a of the double cored bar 34 and a seal that is fixed to the second cored bar 34 and that the radially inner end 44c of the lip tip 44b slides on the outer peripheral surface of the inner ring 12. And a lip portion 44. Therefore, even if the shaft is eccentric or inclined, the contact portion 43 of the elastic body 40 follows the eccentricity or inclination of the shaft, so that the contact between the seal lip portion 44 and the outer peripheral surface of the inner ring 12 is maintained. Is possible. Further, since the seal lip portion 44 is fixed to the second cored bar 34, the interference with the outer peripheral surface of the inner ring 12 and the tightening force can be kept constant, and good sealing performance can be exhibited. is there.
Further, the radial thickness E between the radially inner end 44c of the lip tip 44b and the radially inner end 50a of the spring 50 is the diameter (outer diameter) of the outer peripheral surface (groove 12b) of the inner ring 12. Since the thickness of the lip tip portion 44b is appropriately set so as to be 1% or more, the pressure resistance (internal pressure resistance, external pressure resistance) of the seal lip portion 44 is improved, and the internal pressure is increased by the temperature rise of the bearing. Even when it rises or when the external pressure of the bearing rises, it is possible to maintain the tightening force against the outer peripheral surface of the inner ring 12 and to suppress the occurrence of fatigue.

  In addition, the thickness of the lip waist portion 44a is appropriately adjusted so that the radial thickness F at the smallest portion of the lip waist portion 44a is 1% or more of the diameter (outer diameter) of the outer peripheral surface (groove portion 12b) of the inner ring 12. Since it is set, the pressure resistance (internal pressure resistance, external pressure resistance) of the seal lip portion 44 is further improved, and even when the internal pressure increases due to the temperature rise of the bearing or when the external pressure of the bearing increases, the inner ring 12 It is possible to further maintain the tightening force with respect to the outer peripheral surface and further suppress the occurrence of fatigue.

  In addition, the radially inner end 44c of the lip tip 44b is in sliding contact with the outer peripheral surface (groove 12b) of the inner ring 12 with an interference G, and the value twice the interference G is Since it is 1% or more of the diameter (outer diameter) of the outer peripheral surface (groove portion 12b) of the inner ring 12, the pressure resistance (internal pressure resistance, external pressure resistance) of the seal lip portion 44 is further improved, and the internal temperature increases due to the temperature rise of the bearing. Even when the pressure rises or when the external pressure of the bearing rises, it is possible to further maintain the pressing force against the outer peripheral surface of the inner ring and to further suppress the occurrence of fatigue.

  Further, the radially inner end portion 32a of the first core metal 32 is positioned on the radially outer side of the radially outer end portion 34a of the second core metal 34, and the connecting portion 43 of the elastic body 40 is directed inward in the axial direction. Therefore, since the cross section is a substantially linear shape inclined inward in the radial direction, when the eccentricity or inclination of the shaft occurs, the connecting portion 43 is easily bent, and the followability to the eccentricity or inclination of the shaft can be improved.

  Further, since the elastic body 40 has the bumper lip portion 45, even when the shaft is tilted or decentered, the bumper lip portion 45 cushions against the outer peripheral surface of the inner ring 12 and the seal lip portion 44 is abnormally worn. It is possible to prevent deformation.

  In addition, this invention is not limited to each embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

  For example, the rolling bearing to which the oil seal 20 is applied is not limited to the self-aligning roller bearing 10 described above, but includes a double row tapered roller bearing with a spherical seat as shown in FIG. 5 and a spherical seat as shown in FIG. A cylindrical roller bearing or a double-row cylindrical roller bearing with a spherical seat (not shown) may be used. 5 and 6 show a state in which the outer ring 11 is arranged on the inner peripheral surface of the spherical seat 80. FIG.

  Further, the oil seal 20 of the present invention may be applied to a double row tapered roller bearing with a spherical seat as shown in FIG. 7 or a cylindrical roller bearing with a spherical seat as shown in FIG. In these bearings, the oil seal 20 is provided so as to close the axial end opening of the space existing between the outer peripheral surface of the inner ring 12 and the inner peripheral surface of the spherical seat 80 disposed radially outside the outer ring 11. The cored bar 30 of the oil seal 20 is press-fitted into a groove 80a formed at the axially outer end of the inner peripheral surface of the spherical seat 80 and fixed.

  In the above-described embodiment, the bumper lip portion 45 is provided as the auxiliary lip portion. However, a dust lip portion that prevents dust from entering from the outside may be used. Further, the auxiliary lip portion is not necessarily limited to the configuration in contact with the outer peripheral surface of the inner ring 12, and may be non-contact as long as a seal is formed with the outer peripheral surface of the inner ring 12. Further, the auxiliary lip portion may not be provided.

10 Spherical roller bearings (rolling bearings)
11 outer ring 11a outer ring raceway groove 11b groove 11A outer ring equivalent member 12 inner ring 12a inner ring raceway groove 12b groove 12A inner ring equivalent member 13 cage 14 roller 15 through hole 20 oil seal (sealing device for rolling bearing)
30 cored bar 32 first cored bar 32a radial inner end 34 second cored bar 34a radial outer end 34b radial inner end 40 elastic body 41 first extension part 42 second extension part 43 connection part 44 Seal lip 44a Lip waist 44b Lip tip 44c Radial inner end 44d Outer peripheral surface 45 Bumper lip (auxiliary lip)
45a Radial inner end portion 50 Spring 50a Radial inner end portion 60 Pressure resistance test device 62 First pressure chamber 64 Second pressure chamber 70 Roll 70a Roll neck portion 71 Housing 72 Shaft side chock seal 73 Roll side chock seal 74 Grease supply hole 75 Space 76 Grease discharge hole 77 Air gap 80 Spherical seat 80a Groove E, F Radial thickness G Interference

Claims (2)

Rolling bearing formed in a substantially annular shape so as to close the axial end opening of the space existing between the outer peripheral surface of the inner ring and the outer peripheral ring or the inner peripheral surface of the spherical seat disposed radially outside the outer ring. A rolling bearing provided with a sealing device for
The rolling bearing sealing device includes a substantially ring-shaped cored bar, an elastic body fixed to the cored bar,
With
The cored bar is fixed to the inner peripheral surface of the outer ring or the spherical seat, and is arranged on the inner side in the axial direction than the first cored bar extending radially inward and the radially inner end of the first cored bar, Divided into a second mandrel extending radially inward,
The elastic body includes a connecting portion that connects a radially inner end portion of the first cored bar and a radially outer end portion of the second cored bar, a seal lip portion fixed to the second cored bar, Have
The seal lip portion includes a lip waist portion fixed to the second core metal, and a lip tip portion that is continuous from the lip waist portion and whose radially inner end portion is in sliding contact with the outer peripheral surface of the inner ring,
On the outer peripheral surface of the lip tip portion, a spring that urges the lip tip portion toward the outer peripheral surface of the inner ring is disposed,
The radial thickness between the radially inner end of the lip tip and the radially inner end of the spring is 1% or more of the diameter of the outer peripheral surface of the inner ring,
Inner diameter of the second core metal is rather smaller than the diameter of the outer peripheral surface of a portion radial thickness of the lip waist is minimized,
The rolling bearing according to claim 1, wherein a radial thickness of the lip waist portion between the spring and the second metal core is 1% or more of a diameter of an outer peripheral surface of the inner ring at a minimum position . The radially inner end of the lip tip is in sliding contact with the outer peripheral surface of the inner ring with an interference.
2 times the value of White said tightening is rolling bearing according to claim 1, characterized in that at least 1% of the diameter of the outer peripheral surface of the inner ring.

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