JP2008223966A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing capable of preventing reduction in the bearing service life, by preventing intrusion of foreign matter, by improving sealability, without being restricted on arrangement of a seal lip, without receiving influence of centrifugal force on the rotary wheel side, with a simple and inexpensive structure. <P>SOLUTION: This rolling bearing is composed of a first seal member 80 fixed to a rotary wheel 16, and a second seal member 90 fixed to a resting wheel 14, and the second seal member 90 is integrally provided with a tapered seal lip 98 forming a seal area contacting by slidingly contacting with the first seal member 80. An inner ring 14 is composed of alloy steel including C by 0.1 to 1.2 wt.% and Cr by 1 to 3 wt.%, and adding Mo by 2.0 wt.% or less, and is constituted by setting a residual austenite quantity of its surface layer to 20 to 45 vol%, and setting an average particle size of fine carbide to 2.3 μm or less, by forming the surface layer by carbonitriding processing. <P>COPYRIGHT: (C)2008,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. 6 (a) and 6 (b) 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 transported along the pass line 2p, and after being rolled to a uniform thickness by a group of rolling rolls, is 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. 7, 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. 6 and 7, 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 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. 7 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. 7 has an annular shield 22 in which an inner diameter 22e is fixed (press-fit) to an inner ring (stationary ring) 14 and an outer diameter 22t is positioned in a non-contact state with respect to an 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.

However, the sealing mechanism (prior art 1) disclosed in Non-Patent Document 1 shown in FIG. 7 has the following problems.
That is, since the seal 24 is disposed on the inner diameter surface of the outer ring which is a rotating wheel, the lip Lp may be separated from the shield 22 by the centrifugal force when the bearing rotates. In this case, depending on the degree of the separation, the sliding contact state between the lip Lp and the shield 22 changes (for example, the sliding contact pressure decreases), and as a result, the sealing performance of the sealing mechanism decreases.
If this happens, it will not be possible to prevent foreign matter (for example, dust, rolling oil) from entering the bearing from the outside of the bearing, and the bearing may be damaged early.

Further, as a rolling bearing assembled to the backing roll shaft 10, a sealing mechanism (prior art 2) according to Patent Document 1 shown in FIG. 8 and a sealing mechanism (prior art 3) according to Patent Document 2 shown in FIG. 9 are provided. Prior art is also presented.
"Prior art 2"

The sealing mechanism according to the prior art 2 includes an annular receiving member 30 that is fixed to the outer ring 16 that is a rotating wheel, and an annular holder 40 that is fixed to the inner ring 14 that is a stationary wheel. Sealing is achieved by bringing two seal rings 48 and 50 separately provided into sliding contact with the rotating receiving member 30.
The receiving member 30 includes a first cylindrical portion 32 on the outer diameter side fitted to the inner diameter surface of the outer ring 16, an annular portion 34 extending in a radial direction from the cylindrical portion 32, and a shaft extending from the annular portion 34. The second cylindrical portion 36 is provided in a non-contact manner with the inner ring 14, and an O-ring 38 is disposed on the outer diameter of the first cylindrical portion 32 in the circumferential direction. ing.
The holder 40 includes a cylindrical portion 42 fitted to the outer diameter surface of the inner ring 14, an annular portion 44 extending in a radial direction from the cylindrical portion 42 and provided in non-contact with the outer ring 16, and the annular ring The cylindrical portion 46 extends in the axial direction from the receiving member facing surface 44a side of the portion 44, and is provided separately on the outer surface 46a side of the cylindrical portion 46 and the cylindrical portion 46 provided in non-contact with the receiving member 30. The first seal ring 48 that is in sliding contact with the first cylindrical portion 32 of the 30, and the second seal ring 50 that is separately provided on the inner surface 46 b side of the cylindrical portion 46 and that is in sliding contact with the second cylindrical portion 36 of the receiving member 30. It consists of and.
In the prior art 2, a lubricating oil recovery hole 52 is provided in the inner ring, and the lubricating oil supplied from the lubricating oil supply hole 54 is recovered to perform circulation lubrication.
"Prior art 3"

The sealing mechanism according to Prior Art 3 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 provided separately is slidably brought into contact with the rotating side plate 60 to achieve sealing.
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. .

However, each of the above prior arts 2 and 3 has the following problems.
“FIG. 8 Problem of Patent Document 1”

In the case of the sealing mechanism disclosed in Patent Document 1 shown in FIG. 8, as the components constituting the sealing mechanism, on the inner ring 14 side, the inner and outer diameters of the second cylindrical portion 36 extending in the axial direction from the holder 40 are respectively provided. A separate fitting process for the first seal ring 48 and the second seal ring 50 is required, and a separate process for fitting and fixing the O-ring 38 is necessary on the outer ring 16 side, so that it takes time and effort for assembling. It was.
Furthermore, since the second seal ring 50 includes a garter spring, it takes time and effort to fit the second seal ring 50. Further, in the case of this prior art, the second cylindrical portion 36 including the first seal ring 48 and the second seal ring 50 is not in contact with the receiving member 30 and extends in the axial direction toward the inside of the bearing. As a whole, the space in the axial direction inside the bearing becomes large as a whole sealing mechanism, and the length of the rolling elements that affect the load resistance of the bearing must be shortened, which reduces the load resistance of the bearing. There was a risk of it. Further, by providing the lubricating oil recovery hole 52 in the axial direction of the inner ring 14, a reduction in load resistance is promoted.
“FIG. 9 Problem of Patent Document 2”

  In the case of the sealing mechanism disclosed in Patent Document 2 shown in FIG. 9, the exhaust holes 62 are provided in the side plate 60, so that foreign matter or rolling oil enters the bearing from the outside of the bearing, and the bearing may be damaged early. there were. Further, since the V-ring seal 74 provided separately in the shield plate 66 needs to be designed so as not to block the exhaust hole 62, there is a restriction on the radial size and arrangement position of the V-ring seal 74. It was what it was.

In addition, foreign materials such as metal chips, shavings, burrs and wear powder may be mixed in the bearing lubricant. These foreign materials may damage the races and rolling elements, resulting in a significant increase in bearing life. May cause a drop. In particular, since the inner ring 14 incorporated in this type of rolling mill is of a type that does not rotate together with the shaft 10, the load applied to the inner ring 14 is always applied in the same phase with respect to the radial load applied to the outer ring 16. 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.
Product catalog (JTEKT Corporation product catalog Multi-stage rolling mill Cylindrical roller bearing for backup roll CAT.NO.246 P5 Figure 4) No. 7-52425 JP 2004-278660 A

  The present invention has been made to solve such problems, and its object is to have a simple and inexpensive structure, without being affected by the centrifugal force on the rotating wheel side, and to restrict the arrangement of the seal lip. It is an object of the present invention to provide a rolling bearing capable of improving the sealing performance without being subjected to the damage and preventing the intrusion of foreign matters and preventing the bearing life from decreasing.

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. A rolling bearing provided with a stationary ring (for example, an inner ring) 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 of molybdenum (Mo). % Of alloy steel added to form a surface layer (also referred to as a rolling surface layer) by carburizing or carbonitriding, and the amount of retained austenite (γR vol%) of the surface layer is 20 to 45 vol%, Constructed with an average particle size of fine carbide or carbonitride of 2.3 μm or less The sealing mechanism is fixed to the rotating wheel and includes a first seal member (for example, a shield) including an annular portion that includes an annular cored bar and an elastic member that covers the cored bar. ), And an annular portion that is fixed to the stationary ring and includes an annular cored bar and an elastic member that covers the cored bar, and the annular part is a circle of the first seal member. A second seal member (for example, a contact seal) disposed to face the ring portion, and the second seal member is formed from the predetermined region of the elastic member that forms the ring portion. An annular seal lip (cone-shaped seal lip having a substantially V-shaped cross-sectional view) that extends in an inclined manner toward the annular portion of the member and forms a contact seal region in sliding contact with the first seal member It is made into the rolling bearing characterized by having.
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, according to the first aspect, since the stationary wheel is configured as described above, it is possible to prolong the life of the stationary wheel without being damaged by the foreign matter even in a foreign matter mixed environment.

According to a second aspect, in the first aspect, 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 second invention, the seal lip is provided on the first seal member that is fixedly provided on the fixed ring side so as to be 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.

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

According to a fourth aspect of the present invention, there is provided a rolling bearing characterized in that in the first aspect of the invention, lubrication is performed inside the bearing using lubricating oil or lubricating oil and compressed air.
According to the fourth 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.

5th invention is the 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 fifth aspect, it is possible to provide a sealing mechanism suitable for the bearing structure of the backing roll shaft in a simple and inexpensive manner.

  According to the present invention, it is possible to prevent foreign substances from entering by improving the sealing performance with a simple and inexpensive structure without being affected by the centrifugal force on the rotating wheel side and without being restricted by the arrangement of the seal lip. It is possible to provide a rolling bearing that can be designed and prevent the bearing life from being lowered.

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, and FIG. 5 shows the fourth embodiment.
Each embodiment is an improvement of the sealing mechanism of the rolling bearing 12 (FIG. 7) used in the multi-stage rolling mill shown in FIG. 6, and therefore only the improved portion will be described below. In this case, with respect to the same configuration as the rolling bearing 12 disclosed in FIG. 7 described above, the same reference numerals as the reference numerals attached to 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. 6 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 FIG. 1 includes a first seal member 80 that is fixedly provided on the outer ring 16 as a rotating wheel, and a second seal member 90 that is fixedly provided on the inner ring 14 as a stationary ring. It consists of and.

In the present embodiment, the inner ring 14 which is a stationary wheel has the following configuration.
The inner ring 14 is made of an alloy steel 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). Or, carbonitriding is performed to form a surface layer (also referred to as a rolling surface layer), the amount of retained austenite (γR vol%) of the surface layer is 20 to 45 vol%, and the average particle size of fine carbide or carbonitride is 2.3. It is set to 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.

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 press-fitted by fitting the outer diameter 82b side to the inner diameter surface of the outer ring 16, and is disposed inward in the axial direction of the bearing. 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 is a cylindrical portion 92 a fitted to the outer diameter surface of the inner ring 14, and a circular plate that extends radially from the cylindrical portion 92 a toward the outer ring 16 and is not in contact with the outer ring 16. A core metal 92 having a substantially L-shaped cross-sectional view composed of a portion 92b, an entire area of the outer diameter surface 92c of the cylindrical portion 92a of the core metal 92, and an entire area of the surface portion 92d on the bearing inward side of the disk portion 92b The annular member 96 that is formed by the elastic member 94 that continuously covers the outer diameter 92e and the elastic member 94 that covers the surface 92d on the inner side of the bearing of the disk member 92b are integrally extended. The contact seal is constituted by a seal lip 98 that is in sliding contact with the first seal member 80 (also referred to as a V-type seal or a Y-type seal from the shape of the seal).
Then, the inner diameter surface of the cylindrical portion 92 a is fitted into the outer diameter surface of the inner ring 14 and press-fitted, and is disposed outward in the axial direction of the bearing so as to face the annular portion 87 of the first seal member 80. .

The seal lip 98 is a bearing of the cored bar 82 in the first seal member 80 from a predetermined region of the elastic member 94 that covers the inner surface 92d of the disk portion 92b of the elastic member 94 constituting the annular portion 96. The first seal member 80 is integrally extended in an inclined shape (inclined outward) toward the outer surface portion 82c, and is slidably contacted with the rotation of the outer ring 16, thereby forming a contact seal region. 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 disk portion 92b, 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.

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.
This embodiment is an embodiment in which a floating ring 100 is provided between double-row cylindrical rollers, and the sealing mechanism of the present invention is applied to the sealing mechanism.
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. 4 is a schematic sectional view showing a part of the rolling bearing according to the third embodiment of the present invention.
In the present embodiment, the sealing mechanism of the present invention is applied to an example in which the outer collar 14a of the inner ring 14 is a separate part.
4A shows a type in which a lubricating oil supply hole 54 is provided in the inner ring, and FIG. 4B 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.
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.
The present embodiment is an embodiment in which 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.
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 3 shown in FIGS. 1 to 4 described above, “cylindrical rollers” are illustrated as the rolling elements 18, and in Example 5 shown in FIG. 5, “conical rollers” are illustrated as the rolling elements 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"

Further, in this embodiment, the disk portion 92b of the cored bar 92 in the second seal member 90 has a flat shape, but the concave portion and the convex portion (not shown) continuous in the circumferential direction 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 a part of Example 2 expanded. 9 is a cross-sectional view showing a part of the third embodiment omitted and enlarged, and (a) shows an embodiment 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 enlarged one part of Example 4, 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. FIG. It is sectional drawing of the rolling bearing which concerns on the prior art 3, (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 Ring portion 90 Second seal member 92 Core metal 94 Elastic member 96 Ring portion 98 Seal lip

Claims (5)

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 stationary ring is mainly made of alloy steel 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). Or, carbonitriding is performed to form a surface layer (also referred to as a rolling surface layer), the amount of retained austenite (γR vol%) of the surface layer is 20 to 45 vol%, and the average particle size of fine carbide or carbonitride is 2.3. It is configured as μm or less,
The sealing mechanism is provided to be fixed to the rotating wheel, and includes a first seal member including an annular core made of an annular cored bar and an elastic member that covers the cored bar,
An annular part that is fixed to the stationary ring and includes an annular cored bar and an elastic member that covers the cored bar, and the annular part is an annular part of the first seal member And a second seal member disposed to face each other.
The second seal member is inclinedly extended from a predetermined region of the elastic member constituting the annular portion toward the annular portion of the first seal member, and is in sliding contact with the first seal member. A rolling bearing comprising an annular seal lip forming a seal region. 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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