JP2008223964A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing capable of releasing pressure from the inside of the bearing to the outside of the bearing, being superior in rotating performance and lubricating performance while preventing the entry of foreign matters. <P>SOLUTION: The rolling bearing comprises an inner ring (a stationary ring) 14 kept in a non-rotated condition, an outer ring (a rotary ring) 16 to be rotated in opposition to the stationary ring, and a sealing mechanism for sealing the inside of the bearing defined between the stationary ring and the rotary ring from the outside of the bearing. The sealing mechanism consists of a seal having a base end 60e fixed to the stationary ring and a front end 60t extending toward the rotary ring, a shield 62 having a base end 62e fixed to the rotary ring and a front end 62t positioned relative to the stationary ring in non-contact therewith, and a seal piece 64 protruded from the seal toward the shield and having a protruded end (a lip Lp) positioned relative to the shield in sliding contact therewith. On the seal fixed to the stationary ring, a valve structure 68 is provided for carrying fluid from the inside of the bearing only to the outside of the bearing. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a rolling bearing having a stationary ring that is maintained in a non-rotating state and a rotating wheel that rotates in opposition to the stationary ring. It is related with the technique for releasing the pressure of the outside to the outside of the bearing.

  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. 2 (a) and 2 (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. 3, the rolling bearing 12 includes an inner ring (stationary wheel) 14 fitted (fixed) to the backing roll shaft 10, and an outer ring (rotatingly disposed facing the inner ring (stationary wheel) 14). (Rotating wheel) 16, a plurality of rolling elements 18 incorporated 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. Thereby, the rolling bearing 12 has comprised the bearing structure of outer ring | wheel rotation.

  In the drawing, the “cylindrical roller” is illustrated as the rolling element 18, but “tapered roller” may be applied. The material of the inner and outer rings 14, 16 and the rolling elements 18 can be formed of a steel material such as alloy steel, for example. Furthermore, in the drawings, as an example, a bearing structure in which two inner rings 14 and one outer ring 16 are arranged to face each other is shown.

  In such a multi-stage rolling mill, as shown in FIG. 2A, 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.

  Further, the rolling bearing 12 is provided with a sealing mechanism that seals the inside of the bearing from the outside of the bearing in order to prevent intrusion of foreign matter (for example, dust, rolling oil) from the outside of the bearing into the inside of the bearing. FIG. 3 shows an example of the sealing mechanism, which is provided between the inner and outer rings 14 and 16 on both sides of the double row rolling elements 18.

  In the sealing mechanism shown in FIG. 3, the base end 48e is fixed (press-fit) to the inner ring (stationary ring) 14, the tip 48t extends toward the outer ring (rotating ring) 16, and the extending end is the outer ring (rotating ring). An annular outer shield 48 positioned in a non-contact state with respect to the wheel 16, and an annular inner shield 50 disposed on the bearing inner side with respect to the outer shield 48. In this case, the inner shield 50 has a base end 50 e fixed to the outer ring (rotating ring) 16 and a distal end 50 t extending toward the inner ring (stationary ring) 14, and the extension end of the inner shield 50 with respect to the inner ring (stationary ring) 14. Is positioned in a non-contact state. The base end 50 e of the inner shield 50 is fitted and fixed to the outer ring (rotating ring) 16 by an annular retaining ring 52. In the drawing, an O-ring 54 is interposed between the base end 50 e of the inner shield 50 and the outer ring (rotating ring) 16, but a sealing material other than the O-ring 54 may be used.

  The outer shield 48 fixed to the inner ring (stationary ring) 14 is provided with a seal structure 56 on the base end 48e side, and the seal structure 56 is in sliding contact with the inner shield 50. Is positioned in a state. Specifically, a lip Lp protruding in a substantially V shape toward the inner shield 50 is integrally formed on the seal structure 56, and the lip Lp is always in sliding contact with the inner shield 50. Further, the inner shield 50 is provided with one or a plurality of small holes H along the circumferential direction for releasing compressed air and lubricant to be described later to the outside of the bearing.

  Further, in the multi-stage rolling mill, a lubricating oil supply system for supplying a lubricant (oil) into the bearing is constructed in order to keep the rolling performance and the lubricating performance of the rolling bearing 12 constant. As an example, in the lubricating oil supply system shown in FIG. 2B, the backing roll shaft 10 has a lubricating oil supply hole 28 formed so as to penetrate the backing roll shaft 10 and an outer periphery of the backing roll shaft 10. A plurality of lubricating oil supply grooves 30 formed by being partially recessed along the circumferential direction are provided.

  In this case, each of the lubricating oil supply grooves 30 and the lubricating oil supply hole 28 communicate with each other through a plurality of communication holes 32 that are radially drilled from the lubricating oil supply hole 28 in the radial direction. The lubricating oil supply grooves 30 are disposed so as to face each other between the inner rings 14 of the rolling bearings 12. Specifically, as shown in FIG. 3, a lubricating oil circulation groove 34 that is continuous in the circumferential direction along the inner circumference is formed between the inner rings 14, and the lubricating oil circulation groove 34 and the lubricating oil are formed. The supply grooves 30 are arranged to face each other. As a result, in the region surrounded by the grooves 30, 34, a lubricating oil path (particularly not denoted by a reference numeral) extending in an annular shape along the circumferential direction is constructed. Further, a lubricating oil supply hole 36 is formed between the inner rings 14 to communicate the lubricant path surrounded by the grooves 30 and 34 with the inside of the bearing.

  According to such a lubricating oil supply system, the lubricating oil supplied to the lubricating oil supply hole 28 from a lubricating oil supply source (not shown) passes through the communication hole 32 and passes through the lubricating oil circulation groove 34 and the lubricating oil supply groove 30. After being introduced into the enclosed lubricating oil passage, it is supplied from the lubricating oil passage through the lubricating oil supply hole 36 into the bearing. In this case, in order to support the flow of the lubricating oil supplied to the inside of the bearing, compressed air is sent from a lubricating oil supply source (not shown) to the lubricating oil supply hole 28, and the compressed air is connected to the communication hole together with the lubricating oil. After being supplied from 32 through the lubricating oil path and the lubricating oil supply hole 36 to the inside of the bearing, it reaches the sealing mechanism through the double row rolling elements 18.

  At this time, as shown in FIG. 4, the compressed air that has reached the sealing mechanism passes through each small hole H provided in the inner shield 50, and then between the tip 48 t of the outer shield 48 and the outer ring (rotating ring) 16. It is discharged from the gap S to the outside of the bearing. At this time, a flow is formed in which the lubricating oil supplied into the bearing is discharged together with the compressed air to the outside of the bearing. As a result, a system for supplying lubricating oil while adjusting the atmospheric pressure between the inside of the bearing and the outside of the bearing has been constructed (Patent Document 1).

However, in the sealing mechanism as described above (FIGS. 3 and 4), since a plurality of small holes H are provided in the inner shield 50 that rotates together with the outer ring (rotating ring) 16, foreign matters such as dust and rolling oil are used. May enter the inside of the bearing through the plurality of small holes H. In this case, if the lubricating oil is contaminated by the foreign matter that has entered, or if the foreign matter enters between the rolling elements 18 and the inner and outer rings 14, 16, the rotational performance and the lubricating performance of the rolling bearing 12 are deteriorated. There is a risk that the rolling bearing 12 will deteriorate early. If it becomes so, it will become impossible to use the rolling bearing 12 continuously and stably over a long period of time.
JP 2004-278660 A

  The present invention has been made in order to solve such problems, and its purpose is to prevent rotation of foreign matters and at the same time to provide rotational performance and lubrication performance capable of releasing the pressure inside the bearing to the outside of the bearing. The object is to provide an excellent rolling bearing.

In order to achieve such an object, the first aspect of the present invention is such that a stationary wheel that is maintained in a non-rotating state, a rotating wheel that rotates opposite to the stationary wheel, and a rolling wheel that is freely rotatable between the stationary wheel and the rotating wheel. A rolling bearing comprising a plurality of incorporated rolling elements and a sealing mechanism for sealing the inside of the bearing defined between the stationary ring and the rotating ring from the outside of the bearing, the sealing mechanism having a base end One seal member (seal) that is fixed to the stationary ring and has a distal end extending toward the rotating wheel, and a base end that is fixed to the rotating ring and the distal end extends toward the stationary ring, and the extending end is stationary The other seal member (shield) positioned in a non-contact state with respect to the ring, and one seal member projecting toward the other seal member, and the projecting end is in sliding contact with the other seal member With a positioned seal piece, one of which is fixed to the stationary ring The seal member is provided with a valve structure that allows fluid to flow only from the inside of the bearing to the outside of the bearing.
According to the first invention, the sealing mechanism can prevent foreign matter from entering, and at the same time, the valve structure can release the pressure inside the bearing to the outside of the bearing. Thereby, the rotational performance and lubrication performance of a rolling bearing can be maintained constant.

In the second invention, 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.
According to the second 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.

A third invention is a rolling bearing in which lubrication oil is supplied to the inside of the bearing for lubrication, and the valve structure has a structure for discharging the lubricating oil supplied to the inside of the bearing to the outside of the bearing. .
According to the third aspect, the supplied lubricating oil is discharged by the valve structure, whereby the rotational performance and the lubricating performance of the rolling bearing can be kept constant.

A fourth invention is a rolling bearing used in a multi-stage rolling mill for rolling a steel material, the multi-stage rolling mill includes a group of rolling rollers for rolling the steel material, and the rolling bearing is It is assembled to the backing roll shaft of the rolling roller group.
According to the fourth invention, by using a rolling bearing having excellent rotational performance and lubrication performance for a multi-stage rolling mill, the multi-stage rolling mill can be stably operated. Can be rolled to a uniform thickness.

  According to the present invention, it is possible to realize a rolling bearing excellent in rotational performance and lubrication performance capable of preventing the intrusion of foreign matters and simultaneously releasing the pressure inside the bearing to the outside of the bearing.

  Hereinafter, a rolling bearing according to an embodiment of the present invention will be described with reference to the accompanying drawings. Since this embodiment is an improvement of the sealing mechanism of the rolling bearing 12 (FIGS. 3 and 4) used in the multi-stage rolling mill (FIGS. 2 (a) and (b)), the improved portion will be described below. Only the explanation of. In this case, for the same configuration as the above-described rolling bearing 12 (FIGS. 3 and 4), the same reference numerals as those used in the configuration are attached to the drawings used in the present embodiment. Description is omitted.

  As shown in FIGS. 1 (a) and 1 (b), in the rolling bearing 12 of the present embodiment, the sealing mechanism includes a base end 60e fixed to the inner ring (stationary ring) 14 and a tip 60t of the outer ring (rotating ring). A seal 60 extending toward 16 and an annular shield 62 disposed on the bearing inner side with respect to the seal 60 are provided. Here, the seal 60 is provided with a seal piece 64 that protrudes from the seal 60 toward the shield 62 and is positioned so that the protruding end is in sliding contact with the shield 62. The shield 62 has a base end 62 e fixed to the outer ring (rotating ring) 16 and a distal end 62 t extending toward the inner ring (stationary ring) 14, and the extension end of the shield 62 is not connected to the inner ring (stationary ring) 14. Positioned in contact.

  In this case, the seal 60 is formed by covering the mandrel 60a with the rubber material 60b, and the seal piece 64 is integrally formed with the rubber material 60b. A rubber lip Lp protruding in a substantially V shape toward the shield 62 is integrally formed at the protruding end of the seal piece 64, and the lip Lp is always in sliding contact with the shield 62. The base end of the shield 62 is fitted and fixed to the outer ring (rotating ring) 16 by an annular retaining ring 66.

  Such a sealing mechanism is provided with a valve structure 68 that adjusts the air pressure between the inside of the bearing and the outside of the bearing. The valve structure 68 is a seal 60 fixed to the inner ring (stationary ring) 14. Is arranged. Here, the valve structure 68 has the same function as an existing relief valve or pressure relief valve that is already known in the art.

  In this case, for example, when the valve structure 68 supports the flow of the lubricating oil supplied to the inside of the bearing, the pressure inside the bearing and the pressure outside the bearing are reduced by the compressed air sent together with the lubricating oil. When the pressure becomes higher than the pressure, air (compressed air) flows from the inside of the bearing to the outside of the bearing to release the pressure inside the bearing to the outside of the bearing. At this time, the compressed air inside the bearing is discharged to the outside of the bearing through the valve structure 68 disposed on the seal 60 fixed to the inner ring (stationary ring) 14. Thereby, since the atmospheric pressure between the inside of the bearing and the outside of the bearing can be adjusted, the rolling bearing can be used continuously and stably over a long period of time.

  Further, since the valve structure 68 also has a function as a so-called check valve, foreign matter (for example, dust, rolling oil) can be prevented from entering from the outside of the bearing to the inside of the bearing. As a result, the performance of the lubricating oil inside the bearing can be maintained constant, so that the rotational performance and lubrication performance of the rolling bearing 12 are maintained constant. As a result, the rolling bearing is continuously and stable over a long period of time. Can be used.

  Further, since the valve structure 68 is disposed on the seal 60 fixed to the inner ring (stationary ring) 14, the valve structure 68 is always kept stationary during rotation of the bearing and is not affected by centrifugal force. As a result, it is possible to prevent the lubricant (oil) from leaking and prevent foreign substances from entering, and at the same time to realize a rolling bearing 12 with excellent rotational performance and lubricating performance that can release the pressure inside the bearing to the outside of the bearing. Can do.

  Furthermore, by using the rolling bearing 12 that realizes such an effect in a multi-stage rolling mill (FIGS. 2A and 2B), the multi-stage rolling mill can be stably operated. Thus, the steel material can be rolled to a uniform thickness.

  As for the number of the valve structures 68, the structure in which one seal 60 on each side of the bearing is provided in FIG. 1 is illustrated, but the present invention is not limited to this. May be. At this time, the number of the valve structures 68 is arbitrarily set according to, for example, the shape and size of the seal 60 or the purpose and environment of use of the bearing, and is not specifically limited here.

  In addition, the arrangement (position) of the valve structure 68 is exemplified in the configuration set between the seal piece 64 and the base end 60e of the seal 60 in FIG. In the drawing, the configuration example in which the seal piece 64 is arranged at the substantially center of the seal 60 is shown. However, instead of this, the valve structure 68 is provided below the seal piece 64. You may arrange | position at the front-end | tip 60t.

  In the above-described embodiment, the “cylindrical roller” is illustrated as the rolling element 18 in FIG. 1, but the same effect can be obtained by applying other “balls” or “conical rollers”. . Furthermore, in the above-described embodiment, the bearing structure in which the rolling elements 18 are arranged in two rows in the axial direction is used. However, the same effect can be obtained even if there are one row or three or more rows in the axial direction.

  In the above-described embodiment, the configuration in which the valve structure 68 is disposed on the seal 60 fixed to the inner ring (stationary ring) 14 in FIG. 1 is illustrated, but the present invention is not limited to this. The valve structure 68 may be arranged on a member other than the seal 60 fixed to the stationary ring 14, or may be arranged directly on the inner ring (stationary ring) 14.

(a) is sectional drawing which expands and shows partially the structure of the rolling bearing which concerns on one embodiment of this invention, (b) is sectional drawing which expands and shows the structure of the sealing mechanism of the figure (a) . (a) is a top view which shows the structural example of the rolling roll group of a multistage rolling mill, (b) is a side view which shows the structural example around a backing roll axis | shaft. Sectional drawing which expands and shows a part of structure of the conventional rolling bearing. Sectional drawing of the sealing mechanism for demonstrating the atmospheric pressure adjustment between the bearing inside and the bearing exterior in the conventional rolling bearing.

Explanation of symbols

14 Inner ring (stationary wheel)
16 Outer ring (rotating wheel)
60 Seal 60e Seal base end 60t Seal tip 62 Shield 62e Shield base end 62t Shield tip 64 Seal piece Lp Lip 68 Valve structure

Claims (4)

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 one seal member having a proximal end fixed to the stationary ring and a distal end extending toward the rotating wheel, a proximal end fixed to the rotating wheel and the distal end extending toward the stationary ring, The other end of the seal member that is positioned in a non-contact state with respect to the stationary wheel, and a state in which the projecting end protrudes from the one seal member toward the other seal member and is in sliding contact with the other seal member. And a sealing piece positioned on the
One rolling member fixed to a stationary ring is provided with a valve structure that allows fluid to flow only from the inside of the bearing to the outside of the bearing.   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. A rolling bearing in which lubrication oil is supplied into the bearing and lubrication is performed,
2. The rolling bearing according to claim 1, wherein the valve structure has a structure for discharging the lubricating oil supplied to the inside of the bearing to the outside of the bearing. 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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