JP2009063095A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a low-cost rolling bearing which is excellent in manufacturing efficiency and can be smoothly rotated at all times by easily adjusting an interference amount between a seal lip and a seal member at any time after a seal mechanism is installed in the bearing. <P>SOLUTION: The seal mechanism is composed of a first seal member 80 fixed to a rotating ring 16 and a second seal member 90 fixed to a static ring 14. The second seal member comprises an annular seal lip 98 integrally extended with inclination from a predetermined range of an elastic member 94 constituting an annular part 96 toward an annular part 87 of the first seal member and brought in slide-contact with the first seal member so as to form a contact seal area. The second seal member has tap holes Ht penetrating a part along a thrust direction and arranged with an equal interval along the circumferential direction, in the part fixed to the static ring. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling bearing including a stationary wheel maintained in a non-rotating state and a rotating wheel that rotates to face the stationary wheel, particularly for preventing foreign matter from entering the bearing from the outside of the bearing. The present invention relates to an improved sealing mechanism.

Conventionally, various multistage rolling mills are known as rolling equipment for producing steel materials. As an example, the multi-stage rolling mill shown in FIGS. 7A and 7B is provided with a plurality of types of rolling roll groups in the housing 2, and a steel material (not shown) inserted from the insertion port 2a. ) Is rolled to a uniform thickness by a group of rolling rolls while being conveyed along the pass line 2P, and then discharged from the discharge port 2b.
Here, the rolling roll group includes a pair of work rolls 4 for rolling the steel material, a plurality of first intermediate rolls 6 that rotatably support the pair of work rolls 4, and the first intermediate rolls 6 that are rotatable. A plurality of second intermediate rolls 8 to be supported are provided, and each second intermediate roll 8 is rotatably supported by each rolling bearing 12 assembled to a plurality of backing roll shafts 10. Each backing roll shaft 10 is always kept stationary (non-rotating state).

  As shown in FIG. 8, the rolling bearing 12 includes an inner ring (stationary wheel) 14 fitted (fixed) to the backing roll shaft 10, and an outer ring (rotation ring) disposed so as to face the inner ring (stationary wheel) 14. (Rotating wheel) 16, a plurality of rolling elements (cylindrical rollers) 18 assembled in a double row between the inner and outer rings 14, 16, and a cage 20 that holds each rolling element 18 one by one at equal intervals. Yes. Thereby, the rolling bearing 12 has comprised the bearing structure of outer ring | wheel rotation. In the illustrated example, the outer ring 16 has a form having a middle collar, and a lubricating oil or lubricating oil and compressed air are used to lubricate the bearing from a lubricating oil supply hole 54 provided in the inner ring 14. Format.

In such a multistage rolling mill, as shown in FIGS. 7 and 8, the outer ring (rotating ring) 16 of the rolling bearing 12 is in pressure contact with the plurality of second intermediate rolls 8, and the second intermediate roll 8 And is positioned so as to be rotatable. In this case, the pressure of each outer ring 16 acts on the pair of work rolls 4 from the second intermediate roll 8 through the first intermediate roll 6, thereby preventing the work roll 4 from being bent. Thereby, the steel material conveyed along the pass line 2 </ b> P is rolled to a uniform thickness by the pair of work rolls 4.
In addition, as a material of the inner / outer rings 14, 16 and the rolling elements 18, for example, a steel material such as alloy steel can be used.

The rolling bearing 12 is provided with a sealing mechanism for sealing the inside of the bearing from the outside of the bearing in order to prevent intrusion of foreign matters (for example, dust, rolling oil) from the outside of the bearing to the inside of the bearing.
Further, in this case, in order to support the flow of the lubricating oil supplied into the bearing, compressed air is sent from a lubricating oil supply source (not shown) to the lubricating oil supply hole 54, and the compressed air, together with the lubricating oil, After being supplied to the inside of the bearing through the lubricating oil path and the lubricating oil supply hole 54, the sealing mechanism is reached through between the double row rolling elements 18.

"Prior art 1"
FIG. 8 shows an example of a sealing mechanism, which is provided between the inner and outer rings 14 and 16 on both sides of the double row rolling elements 18 (Non-Patent Document 1).

The sealing mechanism shown in FIG. 8 has an annular shield 22 having an inner diameter 22e fixed (press-fit) to the inner ring (stationary ring) 14 and an outer diameter 22t positioned in a non-contact state with respect to the outer ring (rotating ring) 16. And an annular seal 24 disposed inside the bearing relative to the shield 22.
Here, the seal 24 has an outer diameter 24 e fixed to the outer ring (rotating ring) 16 and an inner diameter 24 t extending toward the inner ring (stationary ring) 14, and an extending end (seal lip) extends from the inner diameter 24 t to the shield 22. It is inclined in the direction and positioned so as to be in sliding contact with the shield 22.

  In this case, the seal 24 is formed by covering the core metal 24a with the rubber material 24b, and a rubber lip Lp protruding in a substantially V shape toward the shield 22 is integrally formed on the inner diameter 24t thereof. The lip Lp is always in sliding contact with the shield 22. The outer diameter 24 e of the seal 24 is fitted and fixed to the outer ring (rotating ring) 16 by an annular retaining ring 26.

"Prior art 2"
As shown in FIG. 9, the sealing mechanism according to Prior Art 2 includes an annular side plate 60 that is fixed to the outer ring 16 that is a rotating wheel, and an annular shield plate 66 that is fixed to the inner ring 14 that is a stationary wheel. The V-ring seal 74 separately provided on the shield plate 66 is slidably brought into contact with the rotating side plate 60 (Patent Document 1).
The side plate 60 is formed in an annular shape with an axial exhaust hole 62 communicating outwardly at a predetermined position, and an O-ring 64 is arranged in the circumferential direction on the outer diameter fitted to the inner diameter surface side of the outer ring 16. It is configured.
The shield plate 66 includes a cylindrical portion 68 fitted to the outer diameter surface side of the inner ring 14, a first annular portion 70 extending in a radial direction from the cylindrical portion 68, and an outer ring extending from the annular portion 70. A second annular portion 72 that extends in a non-contact axial direction and a V-ring seal 74 that is separately provided on the outer diameter of the first annular portion 70 and that is in sliding contact with the side plate 60 are configured. .

  By the way, in the sealing mechanism (FIG. 8) of the prior art 1 (Non-patent Document 1), the amount of interference between the lip Lp of the seal 24 and the shield 22 is, for example, the inner ring (stationary ring) 14 of the inner diameter 22e of the shield 22. The thrust direction dimension of the portion that is press-fitted in the thrust direction and fixed, the thrust direction dimension of the portion that fixes the outer diameter 24e of the seal 24 to the outer ring (rotating wheel) 16, the thrust direction dimensions of the shield 22 and the seal 24, Alternatively, it is defined by the axial internal clearance dimension of the bearing.

  In this case, when the inner diameter 22e of the shield 22 is pressed and fixed in the thrust direction with respect to the inner ring (stationary ring) 14, the interference amount between the lip Lp of the seal 24 and the shield 22 is set in that state. It will be. At this time, the amount of interference between the lip Lp and the shield 22 increases depending on the degree of the press-fitting amount, and the sliding torque of the lip Lp with respect to the shield 22 may increase. And depending on the degree of the torque increase, it may be difficult to smoothly rotate the bearing.

  In order to avoid such a problem, before fixing the sealing mechanism (shield 22, seal 24) to the inner ring (stationary ring) 14, the dimensions described above may be changed in advance or the sealing mechanism may be changed. It ’s fine. However, since it takes time and effort required for that, not only the manufacturing efficiency of the bearing is lowered, but also the cost for the change is added separately, so the manufacturing cost of the bearing is increased accordingly. . Further, in the above-described sealing mechanism, when the interference amount is adjusted after being incorporated in the bearing, there is a problem that the sealing mechanism must be removed from the bearing and cannot be endured.

  In the sealing mechanism (FIG. 9) of Prior Art 2 (Patent Document 1), the amount of interference between the V-ring seal 74 of the shield plate 66 and the side plate 60 is, for example, that the cylindrical portion 68 of the shield plate 66 is connected to the inner ring 14. The thrust direction dimension of the portion that fits (press-fits) in the thrust direction, the thrust direction dimension of the portion that fixes the side plate 60 to the outer ring 16, the thrust direction size of the side plate 60, the shield plate 66, and the V ring seal 74, or It is defined by the axial internal clearance dimension of the bearing.

  In this case, when the cylindrical portion 68 of the shield plate 66 is fitted to the inner ring 14 in the thrust direction (press-fit), the interference amount between the V-ring seal 74 of the shield plate 66 and the side plate 60 is in that state. Will be set. At this time, the amount of interference between the V ring seal 74 and the side plate 60 increases depending on the degree of the press-fitting amount, and the sliding torque of the V ring seal 74 with respect to the side plate 60 may increase. And depending on the degree of the torque increase, it may be difficult to smoothly rotate the bearing.

In order to avoid such a problem, the dimensions described above may be changed in advance or the sealing mechanism may be changed before fixing the sealing mechanism (side plate 60, shield plate 66) to the inner ring 14. However, since it takes time and effort required for that, not only the manufacturing efficiency of the bearing is lowered, but also the cost for the change is added separately, so the manufacturing cost of the bearing is increased accordingly. . Further, in the above-described sealing mechanism, when the interference amount is adjusted after being incorporated in the bearing, there is a problem that the sealing mechanism must be removed from the bearing and cannot be endured.
Product catalog (JTEKT Corporation product catalog Multi-stage rolling mill Cylindrical roller bearing for backup roll CAT.NO.246 P5 Figure 4) JP 2004-278660 A

  The present invention has been made to solve such a problem, and its purpose is to easily adjust the amount of interference between the seal lip and the seal member at any time after the seal mechanism is incorporated in the bearing. Another object of the present invention is to provide a low-cost rolling bearing excellent in manufacturing efficiency that can prevent a sliding torque from increasing and always rotate smoothly.

In order to achieve such an object, the first invention includes a stationary wheel (for example, an inner ring) maintained in a non-rotating state, a rotating wheel (for example, an outer ring) that rotates opposite to the stationary wheel, and a stationary wheel, A plurality of rolling elements (for example, cylindrical rollers) that are rotatably integrated with the rotating wheel, and a sealing mechanism for sealing the inside of the bearing defined between the stationary wheel and the rotating wheel from the outside of the bearing. The rolling bearing provided includes a first seal member (for example, a shield) fixed to the rotating wheel, and a second seal member fixed to the stationary wheel facing the first seal member. (For example, a contact seal), at least one of the first seal member and the second seal member is extended toward the mating seal member and is in sliding contact with the mating seal member. An annular seal lip made of an elastic member. In the second seal member, the portion fixed to the stationary ring has a tap hole penetrating the portion along the thrust direction along the circumferential direction, etc. The rolling bearing is characterized by being arranged at intervals.
According to the first aspect of the present invention, the second seal member disposed on the stationary wheel side is provided with the seal lip that forms a contact seal region by sliding contact with the first seal member that rotates together with the rotating wheel. Therefore, there is no problem that the seal lip forming the contact seal area is opened by centrifugal force and the seal performance is deteriorated as in the prior art.
In addition, since the sealing lip is integrally provided in a predetermined region of the elastic member integrally forming the sealing member, the process for assembling the sealing mechanism is simple, and the space for the sealing mechanism in the bearing is saved. Can be realized.
Furthermore, by providing a tap hole in the portion of the second seal member fixed to the stationary ring, after the sealing mechanism is fixed to the bearing, the second seal can be simply turned by inserting a screw into the tap hole. The member can be moved in the thrust direction. As a result, it is possible to easily adjust the amount of interference between the seal lip and the first seal member at any time to suppress an increase in the sliding torque, and as a result, the bearing can always rotate smoothly. it can. Moreover, such an effect is realized only by disposing a tap hole in the second seal member, and it does not require labor, time, and cost required for that. As a result, it is possible to improve the manufacturing efficiency of the bearing and simultaneously reduce the manufacturing cost.

According to a second aspect of the present invention, in the first aspect of the present invention, the rolling bearing is characterized in that a screw that is spirally continuous along the thrust direction is formed on the inner periphery of the tap hole.
According to the second invention, since the screw is formed in the tap hole, the screw can be stably rotated and the amount of rotation of the screw can be finely adjusted. Accordingly, the interference amount between the seal lip and the first seal member can be adjusted with high accuracy and delicately according to the purpose of use or the environment of use of the bearing.

According to a third invention, in the first invention, the first seal member is disposed in the bearing inner direction with respect to the second seal member, and the annular seal lip is provided on the fixed side of the first seal member. The rolling bearing is characterized by being inclined toward the direction.
According to the third aspect of the invention, the seal lip is provided on the first seal member that is fixedly provided on the fixed ring side and inclined outward (specifically, for example, the annular portion of the first seal member). Therefore, intrusion of foreign matter, rolling oil, etc. from the outside of the bearing can be prevented.
Further, by adopting such a seal lip configuration, if the bearing internal pressure becomes higher than the sum of the rigidity of the seal lip and the bearing external pressure, the seal lip is opened by the bearing internal pressure and the lubricating oil and air are discharged. Therefore, it is possible to create a flow of lubricating oil supplied into the bearing without providing a recovery hole or exhaust hole in the inner ring or the sealing mechanism. Lubrication failure can be prevented. In addition, since no exhaust hole is provided, it is possible to prevent foreign matter or rolling oil from entering through the exhaust hole, which can contribute to early damage of the bearing.

In a fourth aspect based on the first aspect, the stationary wheel is configured as an inner ring disposed opposite to the inner side of the rotating wheel, and the rotating wheel is configured as an outer ring disposed opposite to the outer side of the inner ring. This is a rolling bearing characterized by this.
According to the fourth aspect of the invention, it is possible to configure an outer ring rotating roller bearing in which the inner ring does not rotate and the outer ring rotates.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the rolling bearing is characterized in that the inside of the bearing is lubricated using lubricating oil or lubricating oil and compressed air.
According to the fifth aspect of the invention, the inside of the bearing is in a lubricating oil supply state. However, since the inner ring and the sealing mechanism are not provided with a recovery hole or an exhaust hole, the load resistance is not deteriorated and the seal lip is not provided. There are no restrictions.

6th invention is a rolling bearing used for the multistage rolling mill which rolls steel materials in 1st invention, Comprising: A multistage rolling mill is provided with the rolling roller group for rolling steel materials. The rolling bearing is a rolling bearing characterized by being assembled to a backing roll shaft of a group of rolling rollers.
According to the sixth aspect of the present invention, it is possible to provide a sealing mechanism suitable for the bearing structure of the backing roll shaft easily and inexpensively.

  According to the present invention, after the sealing mechanism is incorporated in the bearing, the amount of interference between the seal lip and the seal member can be easily adjusted at any time to prevent an increase in sliding torque and always rotate smoothly. Therefore, it is possible to realize a low-cost rolling bearing excellent in manufacturing efficiency.

Hereinafter, a rolling bearing according to an embodiment of the present invention will be described with reference to the accompanying drawings.
1 and 2 show the first embodiment, FIG. 3 shows the second embodiment, FIG. 4 shows the third embodiment, FIG. 5 shows the fourth embodiment, and FIG.
Each of the embodiments is an improvement of the sealing mechanism of the rolling bearing 12 (FIG. 8) used in the multi-stage rolling mill shown in FIG. 7, and therefore only the improved part will be described below. In this case, with respect to the same configuration as the rolling bearing 12 disclosed in FIG. 8 described above, the same reference numerals as those used in the configuration are attached to the drawings used in the present embodiment to explain the configuration. Omitted. That is, in this embodiment, for example, in order to support the flow of the lubricating oil supplied into the bearing, compressed air is sent together with the lubricating oil from a lubricating oil supply source (not shown) to the lubricating oil supply hole 54, and the compression The air employs a lubrication configuration in which the air is supplied together with the lubricating oil through the lubricating oil path and the lubricating oil supply hole 54 and then reaches the sealing mechanism through the two rows of rolling elements 18.
Of course, the case where only the lubricating oil is supplied without compressed air is also within the scope of the present invention.
In the rolling bearing of the present embodiment, the lubricating oil recovery hole is not provided in the inner ring 14, and the compressed air discharge hole is not provided in the sealing mechanism.
Furthermore, in this embodiment, as an application example of the rolling bearing of the present invention, the multi-stage rolling mill shown in FIG. 7 is used as described above, but the rolling bearing of the present invention is limited to this multi-stage rolling mill. However, the design can be changed within the scope of the present invention. In the present embodiment, the inner ring 14 is described as a stationary wheel and the outer ring 16 is a rotating wheel. However, it is within the scope of the present invention to apply the inner ring 14 as a rotating wheel and the outer ring 16 as a stationary wheel.

  The sealing mechanism of this embodiment shown in FIGS. 1 and 2 includes a first seal member 80 provided with a base end 80a fixed to an outer ring 16 as a rotating wheel, and a base end 90a on an inner ring 14 as a stationary ring. It is comprised with the 2nd seal member 90 fixed and provided.

The first seal member 80 has a continuous outer diameter 82b together with an annular cored bar 82 provided in non-contact with the inner ring 14 and the entire region of the bearing inner side surface 82a of the cored bar 82. A shield including an annular portion 87 composed of an elastic member 84 to be covered is fitted into the inner surface of the outer ring 16 with the outer diameter 82b side (base end 80a) being press-fitted, and arranged inward in the axial direction of the bearing. It is installed. The elastic member 84 protrudes slightly toward the inner ring 14 from the inner diameter of the cored bar 82 and is provided in non-contact with the inner ring 14. Therefore, the surface portion 82c on the bearing outer side of the cored bar 82 is not covered with the elastic member 84 and the cored bar 82 is exposed.
In the figure, 86 is a retaining ring for fixing the first seal member 80.

  The second seal member 90 has a base end 90a that is press-fitted and fixed to a stepped portion 14p formed on the outer diameter surface of the inner ring 14 on the bearing outer side. Here, the stepped portion 14p includes an annular press-fit surface P1 in which a part of the bearing outer side is continuously extended in the thrust direction along the circumferential direction, and a radial direction from the bearing inner side of the press-fit surface P1. And an annular contact surface P2 continuously raised in the circumferential direction.

  In this case, the second seal member 90 is based on a hollow cylindrical portion 92a that is press-fitted into the press-fitting surface P1 of the inner ring 14, and an annular upright portion 92b that is raised in the radial direction from the bearing inner side of the cylindrical portion 92a. A cored bar 92 including a disk part 92c that is provided in the end 90a and extends radially from the base end 90a in the direction of the outer ring 16 and is not in contact with the outer ring 16, and a bearing inner side of the disk part 92c Of the elastic member 94 that covers the entire area of the surface portion 92d and the elastic member 94 that continuously covers the outer diameter 92e and the surface portion 92d on the inner side of the bearing of the disk portion 92c. It is a contact seal that is integrally extended from the region and is constituted by a seal lip 98 that is in sliding contact with the first seal member 80 (also called a V-type seal or a Y-type seal from the shape of the seal).

The seal lip 98 extends from a predetermined region of the elastic member 94 covering the bearing inner surface 92d of the disk portion 92c of the elastic member 94 constituting the annular portion 96 to the core metal 82 of the first seal member 80. A seal region in contact with the first seal member 80 that is integrally extended in an inclined shape (inclined outward) toward the outer surface portion 82c of the bearing and that rotates as the outer ring 16 rotates. Is an annular seal lip.
Specifically, according to the present embodiment, from the substantially central position in the radial direction between the inner diameter and the outer diameter of the disc portion 92c, the wall portion is thinner than the branch portion 98a through the thick cylindrical branch portion 98a. An overall conical shape having a substantially V-shaped cross-sectional view inclined toward the outer diameter 82b direction which is the fixed side of the first seal member 80 (the large diameter D1 side is opposed to the first seal member 80 direction) The seal lip has a shape that is
The size of the seal lip 98, the position of the seal lip 98, and the size of the contact area are not particularly limited and can be changed within the scope of the present invention according to specifications. For example, the seal lip 98 can be made large to have a long structure with low rigidity.

  Further, in the sealing mechanism of the present embodiment, a tap hole Ht that penetrates the portion along the thrust direction in the portion fixed to the inner ring 14 in the base end 90a of the second seal member 90 extends along the circumferential direction. Are arranged at regular intervals. In the configuration example shown in the figure, tap holes Ht are arranged at equal intervals along the circumferential direction in the upright portion 92b of the base end 90a, and the inner circumference of the tap hole Ht is continuously spiraled along the thrust direction. Screw St is formed. The tap hole Ht is formed by, for example, drilling the raised portion 92b with an existing drill and then inserting the tap as an existing processing tool into the hole while turning the tap hole Ht. can do.

  In this case, the cylindrical portion 92a is press-fitted into the press-fit surface P1 of the inner ring 14, and the upright portion 92b is applied to the contact surface P2 of the inner ring 14, whereby the base end 90a of the second seal member 90 is placed on the inner ring 14. It can be fixed to the stepped portion 14p. In this state, by inserting an existing screw (not shown) into the tap hole Ht (screw St) formed in the upright portion 92b and turning it, the second seal member 90 is moved to the outside of the bearing along the thrust direction. Can be made. For example, when the amount of interference between the seal lip 98 and the first seal member 80 is large in a state where the base end 90a of the second seal member 90 is fixed to the stepped portion 14p of the inner ring 14, the tap hole Ht ( The amount of interference can be reduced by turning the screw threaded with the screw St) and moving the second seal member 90 to the bearing outer side.

As described above, by providing the tap hole Ht in the portion fixed to the inner ring 14 of the second seal member 90 as in the present embodiment, after fixing the sealing mechanism to the bearing, the existing screw is inserted into the tap hole Ht. The second seal member 90 can be moved to the outside of the bearing along the thrust direction simply by turning and turning. As a result, the amount of interference between the seal lip 98 and the first seal member 80 can be easily adjusted at any time to suppress an increase in sliding torque, and as a result, the bearing is always rotated smoothly. be able to.
Moreover, such an effect is realized only by disposing the tap hole Ht at the base end 90a of the second seal member 90, and it does not require labor, time, and cost required for that. As a result, it is possible to improve the manufacturing efficiency of the bearing and simultaneously reduce the manufacturing cost.
Furthermore, by forming the screw St in the tap hole Ht, the existing screw can be stably rotated and the amount of rotation of the screw can be finely adjusted. As a result, the amount of interference between the seal lip 98 and the first seal member 80 can be adjusted with high accuracy and delicately according to the purpose of use or environment of use of the bearing.

  In the above-described embodiment, the hole diameter and the hole length of the tap hole Ht are not particularly mentioned. For example, the thickness and the shape of the base end 90a (upper portion 92b) of the second seal member 90 are used. Therefore, it is not particularly limited here. Further, the pitch and size of the screw thread (thread groove) of the screw St formed in the tap hole Ht in a spiral shape is arbitrarily set according to, for example, the pitch and size of the existing screw to be inserted into the tap hole Ht. Therefore, there is no particular limitation here. Further, the number of tap holes Ht is arbitrarily set according to the shape and width of the base end 90a (upper portion 92b) of the second seal member 90 that forms the tap hole Ht. Then there is no particular limitation.

Further, by being configured as in the present embodiment, the sealing mechanism can particularly prevent intrusion of foreign matter, rolling oil, and the like from the outside of the bearing.
In addition, with such a sealing mechanism, the bearing internal pressure is the sum of the rigidity of the seal lip 98 and the bearing external pressure in a type in which lubrication is performed using lubricating oil or lubricating oil and compressed air as in this embodiment. If higher, the seal lip 98 is opened by the bearing internal pressure, and the lubricating oil and air are discharged. Accordingly, it is possible to create a flow of lubricating oil supplied into the bearing without providing a recovery hole or an exhaust hole in the inner ring 14 or the sealing mechanism, thereby preventing poor lubrication inside the bearing and in the seal lip 98 region. . In addition, since no exhaust hole is provided, it is possible to prevent foreign matter or rolling oil from entering through the exhaust hole, which can contribute to early damage of the bearing.
According to the present embodiment, the second seal member 90 disposed on the inner ring 14 is provided with the seal lip 98 that slides on the first seal member 80 that rotates together with the outer ring 16 to form a seal region of contact. Therefore, there is no problem that the sealing lip forming the contact sealing region as in the prior art is opened by the centrifugal force and the sealing performance is deteriorated.
In addition, since the seal lip 98 is integrally provided in a predetermined region of the elastic member 94 integrally forming the second seal member 90, the process of incorporating the seal mechanism is simple, and the seal mechanism inside the bearing is It is possible to save the installation area.
Further, according to the present embodiment, the inside of the bearing is in a lubricating oil supply state. However, since the inner ring 14 and the sealing mechanism are not provided with a recovery hole or an exhaust hole, the load resistance is not deteriorated and the seal is sealed. There are no restrictions on the lip 98. That is, the seal lip 98 may be in contact (sliding contact) as long as it is a surface portion 82c on the bearing outer side of the metal core 82 of the first seal member 80, and the adjustment of the lip opening pressure of the seal is easy. .

FIG. 3 is a schematic sectional view showing a part of the rolling bearing according to the second embodiment of the present invention.
In this embodiment, in the above-described rolling bearing sealing mechanism (FIG. 8), a portion of the base end (inner diameter 22e) of the second seal member (shield 22) fixed to the inner ring 14 (stepped portion 14p) The tap holes Ht penetrating the portion along the thrust direction are arranged at equal intervals along the circumferential direction. Since the other configuration is the same as the bearing configuration of FIG. 8, the description thereof is omitted.
Moreover, since the effect of a present Example is the same as that of Example 1 mentioned above, the description is abbreviate | omitted.

FIG. 4 is a schematic sectional view showing a part of the rolling bearing according to the third embodiment of the present invention.
The present embodiment is an embodiment in which a floating ring 100 is provided between double-row cylindrical rollers. The sealing mechanism of the present invention is applied to the sealing mechanism, and the second sealing member 90 is based on the sealing mechanism. In the end 90a, tap holes Ht penetrating through the portion along the thrust direction are arranged at equal intervals along the circumferential direction in a portion fixed to the inner ring 14 (stepped portion 14p).
The floating ring 100 cooperates with the inner ring collars 14a and 14a and the outer ring collar 16a to restrict the axial movement of the rolling elements (cylindrical rollers) 18 in each row and to prevent the rolling elements (cylindrical rollers) 18 from skewing. This is a well-known configuration to prevent.
Since other configurations and operational effects are the same as those of the first embodiment, description thereof is omitted.

FIG. 5 is a schematic sectional view showing a part of the rolling bearing according to the fourth embodiment of the present invention.
In this embodiment, the sealing mechanism of the present invention is applied to an example of an embodiment in which the outer collar 14a of the inner ring 14 is a separate part. In the sealing mechanism, the inner ring 14 (of the base end 90a of the second seal member 90) In this configuration, tap holes Ht penetrating the portion along the thrust direction are arranged at equal intervals along the circumferential direction in the portion fixed to the outer collar 14a).
5A shows a type in which the lubricating oil supply hole 54 is provided in the inner ring, and FIG. 5B shows a spacer 102 between the inner rings 14 and 14 and a floating ring between the rolling elements (cylindrical rollers) 18 and 18. 1 is an embodiment including 100. In this embodiment, a step 14p is formed on the outer collar 14a, and the base end 90a of the second seal member 90 is press-fitted and fixed to the step 14p.
Since other configurations and operational effects are the same as those of the first embodiment, description thereof is omitted.

FIG. 6 is a schematic cross-sectional view showing a partially omitted rolling bearing according to Embodiment 5 of the present invention.
In the present embodiment, the sealing mechanism of the present invention is applied to a double-row tapered roller bearing incorporating a double-row tapered roller as the rolling element 18, and in the sealing mechanism, the base end 90 a of the second seal member 90 is provided. Of these, tap holes Ht penetrating the portion along the thrust direction are arranged at equal intervals along the circumferential direction in the portion fixed to the inner ring 14 (stepped portion 14p).
Since other configurations and operational effects are the same as those of the first embodiment, description thereof is omitted.
"Modification 1"

In each of the above-described embodiments, the seal lip 98 has a single structure, but for example, the first seal member 80 may include a plurality of lips that contact the surface portion 82c on the bearing outer side of the cored bar 82. It is within the scope of the present invention. The plurality of lips may be branched from the seal lip 98 of the present embodiment, or may protrude from a predetermined region of the elastic member 94 separately from the seal lip 98 of the present embodiment. Good, but care must be taken to ensure that the torque is not too high.
"Modification 2"

In Examples 1 to 4 shown in FIGS. 1 to 5 described above, a “cylindrical roller” is illustrated as the rolling element 18, and in Example 5 illustrated in FIG. 6, “conical roller” is illustrated as the rolling element 18. However, the same effect can be obtained even if other rolling element forms such as “balls” are applied. Further, in each of the embodiments described above, the bearing structure is provided with the rolling elements 18 in two rows in the axial direction. However, the same effect can be obtained by using one row or three or more rows in the axial direction.
“Modification 3”

Foreign materials such as metal chips, shavings, burrs, and wear powder may be mixed in the bearing lubricant, and these foreign materials may damage the races and rolling elements, resulting in a significant decrease in bearing life. You may be invited. The inner and outer rings 14 and 16 and the rolling elements 18 can be formed of a steel material such as alloy steel as in the conventional case. However, since the inner ring 14 does not rotate with the shaft 10, The load applied to the inner ring 14 is always applied in the same phase with respect to the applied radial load. Therefore, the inner ring 14 has a fatigue life earlier than the outer ring 16 and the rolling elements 18. That is, there is also a problem that the life is likely to be shortened due to damage caused by foreign matter.
Therefore, the inner ring as a stationary ring is preferably configured as follows.
That is, for example, for example, an alloy mainly containing carbon (C); 0.1 to 1.2% by weight, chromium (Cr); 1 to 3% by weight, and further containing 2.0% by weight or less of molybdenum (Mo). Made of steel, carburized or carbonitrided to form a surface layer (also called rolling surface layer), the amount of retained austenite (γR vol%) of the surface layer is 20 to 45 vol%, fine carbide or carbonitride The average particle size is 2.3 μm or less.
Moreover, it is preferable that the average particle diameter of a fine carbide | carbonized_material or a carbonitride shall be 0.5-1.5 micrometers, for example.
The surface hardness (Hv) of the surface layer is in the range of −4.7 × (γR vol%) + 920 ≦ Hv ≦ −4.7 × (γR vol%) + 1020 with respect to the amount of retained austenite (γR vol%). Is preferred.
Further, the molybdenum (Mo) content is preferably 1/3 or more of the chromium (Cr) content.
By configuring the inner ring 14 in this way, an effect that the life of the inner ring 14 can be extended is obtained.
“Modification 4”

In the present embodiment, the disk portion 92c of the cored bar 92 in the second seal member 90 has a flat shape, but the circumferentially continuous concave portion and convex portion (not shown) have the same axial center. It is also possible to construct a side-view wave shape by being arranged in concentric circles within the scope of the present invention. By configuring in this manner, the strength of the cored bar 92 can be improved, and deformation at the time of press-fitting into the inner ring 14 can be prevented. Accordingly, it is possible to prevent a problem that the seal lip 98 strikes the first seal member 80 too much due to the deformation of the metal core 92, or the seal lip 98 does not hit the first seal member 80 and the contact seal area is not formed. be able to. As a result, the bearing can be prevented from early seizure due to poor lubrication or contamination, and the life of the bearing can be improved.
Moreover, this uneven | corrugated structure may be the form which each concave part and convex part are not comprised circularly but meandered. Further, the concave portion and the convex portion may have different sizes (depth, height, width, etc.). Furthermore, the concave portion and the convex portion may be provided intermittently.

It is sectional drawing which abbreviate | omits and shows a part of Example 1 which is one Embodiment of this invention rolling bearing while expanding. It is sectional drawing which expands and shows the structural part of the sealing mechanism of FIG. It is sectional drawing which abbreviate | omits and shows an enlarged view of Example 2, (a) is sectional drawing which abbreviate | omits and shows a structure of a rolling bearing partially, (b) is sealing of (a) It is sectional drawing which expands and shows the structural part of a mechanism. It is sectional drawing which abbreviate | omits and shows a part of Example 3 expanded. FIG. 6 is a cross-sectional view showing a part of the fourth embodiment omitted and enlarged, in which (a) shows a form in which the outer collar of the inner ring is a separate collar ring and the sealing mechanism constituting the present invention is incorporated in the collar ring. , (B) is an embodiment in which the inner collar of the outer ring is eliminated, a floating ring is installed between the rollers, the outer collar of the inner ring is a separate collar, and the sealing mechanism constituting the present invention is incorporated in the collar ring. It is. It is sectional drawing which abbreviate | omits and shows an enlarged view of Example 5, and is one Embodiment which applied this invention to the double row tapered roller bearing. In one application example of the rolling bearing of the present invention, (a) is a schematic side view showing a configuration example of a rolling roll group of a multi-stage rolling mill, and (b) is a schematic front view showing a configuration example around a backing roll axis. is there. It is sectional drawing of the rolling bearing which concerns on the prior art 1, (a) is sectional drawing which abbreviate | omits and shows the structure of the conventional rolling bearing incorporated in the backing roll axis | shaft partially, (b) is ( It is sectional drawing which expands and shows the structural part of the sealing mechanism of a). It is sectional drawing of the rolling bearing which concerns on the prior art 2, (a) is schematic sectional drawing which shows the whole, (b) is sectional drawing which expands and shows the structural part of the sealing mechanism of (a).

Explanation of symbols

14 Inner ring (stationary wheel)
16 Outer ring (rotating wheel)
18 Rolling body 80 First seal member 82 Core metal 84 Elastic member 87 Annular portion 90 Second seal member 92 Core metal 94 Elastic member 96 Annular portion 98 Seal lip Ht Tap hole

Claims (6)

A stationary wheel maintained in a non-rotating state, a rotating wheel that rotates opposite to the stationary wheel, a plurality of rolling elements that are rotatably incorporated between the stationary wheel and the rotating wheel, and a stationary wheel and a rotating wheel A rolling bearing provided with a sealing mechanism for sealing the inside of the bearing partitioned from the outside of the bearing,
The sealing mechanism includes a first seal member fixed to the rotating wheel, and a second seal member fixed to the stationary wheel facing the first seal member,
At least one of the first seal member and the second seal member is provided with an annular seal lip made of an elastic member extending toward the mating seal member and in sliding contact with the mating seal member. And
A rolling bearing according to the second seal member, wherein tap holes penetrating the portion along the thrust direction are arranged at equal intervals along the circumferential direction in the portion fixed to the stationary ring.   The rolling bearing according to claim 1, wherein a screw that is spirally continuous along the thrust direction is formed on an inner periphery of the tap hole. The first seal member is disposed in the bearing inner direction than the second seal member,
The rolling bearing according to claim 1, wherein the annular seal lip is inclined toward a fixed side direction of the first seal member.   The rolling ring according to claim 1, wherein the stationary wheel is configured as an inner ring disposed opposite to the inner side of the rotating ring, and the rotating wheel is configured as an outer ring disposed opposite to the outer side of the inner ring. bearing.   The rolling bearing according to claim 1, wherein lubrication is performed inside the bearing using oil or oil and compressed air. A rolling bearing used in a multi-stage rolling mill for rolling steel materials,
The rolling bearing according to claim 1, wherein the multi-stage rolling mill includes a rolling roller group for rolling the steel material, and the rolling bearing is assembled to a backing roll shaft of the rolling roller group. .

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