JP2009297763A - Bearing device for back up roll - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing device for back up rolls, wherein grease is easily filled up when assembling, the life of a bearing is long and it resists the use for a long period with low torque. <P>SOLUTION: A plurality of radial bearings 14 for loading radial load are interposed between a roll 13 and a shaft 12. A groove 25 is provided in a portion between two radial bearings 14 arranged adjacently on the surface of the inside diameter of the roll 13, and grease is filled up in the groove 25. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a backup roll bearing device used for a tension leveler or the like in a rolling process of a steel material.

  A roller leveler or a tension leveler is used as a straightening machine for correcting a shape defect such as waving or warping in a metal plate or metal strip. These levelers repeatedly apply bending and unbending deformation to a leveling material such as a metal plate, and remove uneven distortion due to stress generated in the plate surface by this deformation. In the tension leveler, the strain removal effect is further enhanced by applying tension in the longitudinal direction of the metal plate.

  For example, in a tension leveler, a work roll, an intermediate roll, and a backup roll are provided as one unit, and the unit is disposed so as to sandwich the leveling material from above and below in the traveling direction, and the work roll is directly attached to the leveling material. Contact level to correct the leveling material.

  FIG. 6 is a cross-sectional view showing a conventional example of a bearing device in the backup roll. In this backup roll bearing device, a plurality of radial bearings (rollers with a cage) 34 that receive a radial load, and a thrust bearing (ball bearing) 35 that is disposed on the outer side in the axial direction of the radial bearing 34 and receives a thrust load, A roll 33 that is a rotating cylinder is rotatably supported with respect to the fixed shaft 32. Since the backup roll is used with the outer ring rotational load, the inner ring 35 a of the thrust bearing 35 is fitted with a clearance to the fixed ring 32, and the outer ring 35 b of the thrust bearing 35 is fitted with the roll 33.

  The rotation of the roll 33 in the backup roll is given by the friction force generated in the roll 33 through the work roll and the intermediate roll that come into contact with the metal plate to be corrected. Therefore, in the backup roll bearing device, it is required to reduce the torque necessary for starting the rotation from the state where the roll 33 is stopped and the torque during the rotation as small as possible.

  Further, since the backup roll bearing device rotates at a relatively high speed, the grease filled in the backup roll to lubricate the radial bearing 34 may move and leak. When the grease leaks, it adheres to the steel plate to be corrected and contaminates the steel plate that is the product.

In the backup roll bearing device shown in FIG. 6, annular side plates 36 such as washers are arranged on both sides of the radial bearing 34 to restrain the movement of the radial bearing 34 in the axial direction. In another conventional example, a retaining ring is arranged on the outer side in the axial direction of the side plate (for example, Patent Documents 1 and 2).
JP 2000-226640 A JP 2000-233212 A

  However, in the above-described configuration, the grease easily escapes from the radial bearing 34 through the side plate and the retaining ring. For this reason, the radial bearing 34 itself becomes insufficiently lubricated, and the rolling fatigue life, which is an essential characteristic of the bearing, may not be sufficiently secured. Further, when the amount of grease to be filled is made up to make up for insufficient lubrication, there arises a problem that torque due to stirring increases.

  In the conventional example shown in FIG. 6, a shallow groove-shaped portion 40 is formed by being surrounded by two side plates 36, 36 disposed on the inner side in the axial direction of the two radial bearings 34 and the inner diameter surface of the roll 33 at the intermediate portion. Therefore, it is conceivable to compensate for insufficient lubrication of the radial bearing 34 by inserting the fixed shaft 32 after filling the groove 40 with grease.

  However, in this case, when the fixed shaft 32 is inserted, there is a possibility that the fixed shaft 32 may scrape off the grease filled in the groove-shaped portion 40, which is insufficient to make up for insufficient lubrication of the radial bearing 34. .

  An object of the present invention is to provide a backup roll bearing device that can be easily filled with grease during assembly, has a long bearing life, and can withstand long-term use with low torque.

The backup roll bearing device according to the present invention is the backup roll bearing device in which a plurality of radial load load radial bearings are interposed between the roll and the shaft, and the radial bearings on the inner diameter surface of the roll are arranged adjacent to each other. A groove is provided in an intermediate portion that is a portion between the gaps, and the groove is filled with grease.
According to this configuration, the groove is provided in the portion between the radial bearings adjacent to each other on the inner diameter surface of the roll, and the groove is filled with grease, so that the base oil of the grease filled in the groove due to heat and vibration during use is reduced. By gradually oozing, it can be used as a lubricating oil for radial bearings. Thereby, insufficient lubrication of the radial bearing can be prevented, and lubricity can be improved. To compensate for the lack of lubrication of the radial bearing, excessive grease is not enclosed in the radial bearing, so torque does not increase. Further, since grease is filled in the groove provided on the inner diameter surface of the roll, the filled grease is not scraped off by the shaft when the shaft is inserted, for example, and the grease can be easily filled at the time of assembly.
As a result, it is possible to provide a backup roll bearing device that can be easily filled with grease during assembly, has a long bearing life, and can withstand long-term use with low torque.

In the present invention, a plurality of the grooves may be arranged in the axial direction.
If the axial length of the part between adjacent radial bearings is long, the number of grooves on the inner diameter surface of the roll can be increased by arranging them in the axial direction. Can be compensated efficiently.

In this invention, it is good also considering the inner wall surface of the axial direction edge part in the said groove | channel as the inclined surface which makes an angle of 30-60 degrees with respect to an axial center.
In the case of this configuration, the base oil of grease filled in the groove can be smoothly supplied to the radial bearing as the roll in operation is rotated. When the angle of the inner wall surface of the groove is smaller than 30 °, the grease itself filled in the groove moves to the radial bearing, and the torque due to stirring increases. Further, if the angle of the inner wall surface of the groove is larger than 60 °, even if the roll rotates, a phenomenon occurs in which the base oil of the grease does not pass over the inner wall surface of the groove and is supplied to the radial bearing.

In this invention, the radial bearing is a roller with a cage formed by holding a plurality of rollers with a cage, and the cage is a rolling element guide type in which an inner diameter portion and an outer diameter portion do not contact the shaft and the roll. Good to have.
If the cage is a rolling element guide type, the inner diameter portion of the cage does not contact the shaft, and the outer diameter portion of the cage does not contact the inner diameter surface of the roll. It will not be scraped off by the vessel, and will easily enter the rolling surface of the radial bearing, improving lubricity.

In the present invention, the radial bearing may be filled with grease of 20 to 40% of the space volume. In addition, the said space volume says the volume of the part except the volume of a rolling element, a holder | retainer, etc. in the space between the components which comprise the inner and outer rolling surfaces in a radial bearing. When the radial bearing is a roller with a cage, the volume of the space excluding the roller with a cage in the space of the cage width between the roll and the shaft is the space volume. When the radial bearing has an inner ring and an outer ring, the volume of the space in the space between the inner ring and the outer ring excluding the cage and the rolling element is the space volume.
If the amount of grease filled is less than the above range, lubrication is insufficient, and if it exceeds the above range, the torque may increase due to the stirring of the grease.

  The backup roll bearing device according to the present invention is the backup roll bearing device in which a plurality of radial load load radial bearings are interposed between the roll and the shaft, and the radial bearings on the inner diameter surface of the roll are arranged adjacent to each other. Since a groove is provided in the gap portion, and this groove is filled with grease, it is easy to fill with grease at the time of assembly, and it is possible to provide a backup roll bearing device that has a long bearing life and can withstand long-term use with low torque.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic view of equipment in the final process of rolling work for steel plates and the like. In this step, the stress of the leveling material 2 such as a steel plate transferred between the drive rolls 1 arranged above and below is removed by the tension leveler 3 which is a straightening machine, thereby ensuring the accuracy of the leveling material 2. . The tension leveler 3 is composed of a plurality of tension leveler units 4 that are arranged above and below the transfer path of the leveling material 2.

  2 and 3 show a side view and a front view of the tension leveler unit 4. The tension leveler unit 4 includes a work roll 5, an intermediate roll 6, and a backup roll 7. The work roll 5 directly contacts the leveling material 2 to correct the leveling material 2. The work roll 5 is supported by the intermediate roll 6 and the backup roll 7, and finally all loads are supported by the backup roll 7.

  FIG. 4 is a cross-sectional view of the backup roll 7 provided with a backup roll bearing device according to an embodiment of the present invention. In this backup roll bearing device, a cylindrical roll 13 externally fitted to a shaft 12 is attached to the shaft 12 with two radial bearings 14 for radial load loading and two ball bearings 15 for thrust load loading. And is supported rotatably. The radial bearing 14 is composed of a roller with a cage in which a plurality of rollers 23 are held by a cage 24, and one radial bearing 14 is arranged on each side of the shaft 12 in the axial direction. The ball bearing 15 is formed of a deep groove ball bearing and is disposed on the axially outer side of the installation position of each radial bearing 14.

  On both sides in the axial direction of each radial bearing 14, annular side plates 16 such as washers fitted on the inner diameter surface of the roll 13 are arranged. The side plate 16 disposed on the inner side in the axial direction is fixed in one axial direction by a step surface 13 a formed on the inner diameter surface of the roll 13. The side plate 16 arranged on the outer side in the axial direction is fixed in one direction in the axial direction with a spacer 17 arranged further on the outer side in the axial direction and fitted to the inner diameter surface of the roll 13. The spacer 17 is engaged with a step surface 13 e provided on the inner diameter surface of the roll 13 and facing outward in the axial direction.

  Since the ball bearing 15 does not apply a radial load, the outer ring 15 b is fixed to the inner diameter surface of the roll 13 by an interference fit, and the inner ring 15 a is a clearance fit with respect to the shaft 12. The ball bearing 15 can support thrust loads in both axial directions, and is fixed to the roll 13 and the shaft 12 in both axial directions. Specifically, the above-described retaining ring 17 disposed on the inner side in the axial direction of the ball bearing 15, and the annular outer diameter side cover 18 disposed on the outer side in the axial direction of the ball bearing 15 and fitted to the inner diameter surface of the roll 13. Thus, the outer ring 15b of the ball bearing 15 is sandwiched and the movement in the axial direction is restricted. Further, a step surface 12 a formed on the inner side in the axial direction of the ball bearing 15 in the shaft 12, and an annular inner diameter side cover disposed on the outer side in the axial direction of the ball bearing 15 in the shaft 12 and fitted to the outer diameter surface of the shaft 12. 19, the inner ring 15a of the ball bearing 15 is sandwiched and the movement in the axial direction is restricted. The outer diameter side cover 18 is axially unidirectional (ball bearings) together with the ball bearing 15 and the spacer 17 by a retaining ring 20 having an outer peripheral portion fitted in a retaining ring groove 13b formed on the inner diameter surface of the roll 13. 15). The inner diameter side cover 19 is fixed in one axial direction (the side opposite to the ball bearing 15) by a retaining ring 21 having an inner diameter portion fitted in a retaining ring groove 12b formed on the outer diameter surface of the shaft 12. The Between the inner diameter surface of the inner ring 15a of the ball bearing 15 and the outer diameter surface of the shaft 12, an annular seal member 22 such as an O-ring for sealing these gaps is interposed.

  As shown in the enlarged cross-sectional view in FIG. 5, an intermediate portion that is a portion between the two radial bearings 14 arranged adjacent to each other on the inner diameter surface of the roll 13, more specifically, the shaft of each radial bearing 14. An annular groove 25 having a predetermined depth over the entire circumference of the inner diameter surface of the roll is provided in an intermediate portion between the two side plates 16 arranged on the inner side in the direction, and the groove 25 is filled with grease. Inner wall surfaces 25 a at both ends in the axial direction of the groove 25 are inclined surfaces that form an angle θ of 30 to 60 ° with respect to the axis O.

According to the backup roll bearing device having the above-described configuration, the groove 25 is provided in the portion where the two radial bearings 14 are arranged adjacent to each other on the inner diameter surface of the roll 13, and the groove 25 is filled with grease. The base oil of the grease filled in the groove 25 gradually oozes out due to heat and vibration at the time, so that it can be used as a lubricating oil for the radial bearing 14. Thereby, insufficient lubrication of the radial bearing 14 is prevented, and lubricity can be improved. To compensate for the insufficient lubrication of the radial bearing 14, excessive grease is not enclosed in the radial bearing 14, so that the torque does not increase. Further, since the groove 25 provided on the inner diameter surface of the roll 13 is filled with grease, the filled grease is not scraped off by the shaft 12 when the shaft 12 is inserted, for example, and the grease can be easily filled at the time of assembly. It is.
As a result, it is possible to provide a backup roll bearing device that can be easily filled with grease during assembly, has a long bearing life, and can withstand long-term use with low torque.

  In this embodiment, the inner wall surfaces 25a at both ends in the axial direction of the groove 25 are inclined surfaces having an angle θ of 30 to 60 ° with respect to the axis O, so that the groove 25 is filled. The grease base oil can be smoothly supplied to the radial bearing 14 with the rotation of the roll 13 during operation. If the angle θ of the inner wall surface 25a of the groove 25 is smaller than 30 °, the grease itself filled in the groove 25 moves to the radial bearing 14, and the torque due to stirring increases. If the angle θ of the inner wall surface 25a of the groove 25 is larger than 60 °, a phenomenon that the base oil of grease does not supply the radial bearing 14 beyond the inner wall surface 25a of the groove 25 even when the roll 13 rotates is generated. To do.

  In this embodiment, when the axial length of the portion between the two radial bearings 14 arranged adjacent to each other is longer, a plurality of grooves 25 on the inner diameter surface of the roll 13 are provided side by side in the axial direction. May be. Providing the plurality of grooves 25 in this way can efficiently compensate for insufficient lubrication of the radial bearing 14 with a small amount of grease.

  In this embodiment, it is desirable that the cage 24 of the radial bearing 14 formed of rollers with cages is a rolling element guide type. When the cage 24 is a rolling element guide type, the inner diameter portion of the cage 24 does not contact the shaft 12, and the outer diameter portion of the cage 24 does not contact the inner diameter surface of the roll 13. The base oil of the grease is not scraped off by the cage 24 and can easily enter the rolling surface of the radial bearing 14, thereby improving the lubricity.

  Furthermore, in this embodiment, the amount of grease sealed in the radial bearing 14 is desirably 20 to 40% of the spatial volume of the radial bearing 14. If the amount of grease filled is less than the above range, lubrication is insufficient, and if it exceeds the above range, the torque may increase due to the stirring of the grease.

It is the schematic which shows the equipment of the last process of rolling operations, such as a steel plate. It is a side view of a tension leveler unit. It is a front view of a tension leveler unit. It is sectional drawing of the backup roll bearing apparatus concerning one Embodiment of this invention. It is a principal part expanded sectional view of the backup roll bearing apparatus. It is sectional drawing of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 ... Shaft 13 ... Roll 14 ... Radial bearing 23 ... Roller 24 ... Cage 25 ... Groove 25a ... Inner wall surface (theta) ... Angle of inner wall surface

Claims (5)

In the backup roll bearing device in which a plurality of radial load load radial bearings are interposed between the roll and the shaft,
A backup roll bearing device, wherein a groove is provided in a portion between the radial bearings adjacent to each other on the inner diameter surface of the roll, and the groove is filled with grease.   The backup roll bearing device according to claim 1, wherein the groove has a plurality of grooves arranged in the axial direction.   The backup roll bearing device according to claim 1 or 2, wherein an inner wall surface of an end portion in the axial direction of the groove is an inclined surface that forms an angle of 30 to 60 degrees with respect to the axis.   The radial bearing according to any one of claims 1 to 3, wherein the radial bearing is a roller with a cage formed by holding a plurality of rollers with a cage, and the cage has an inner diameter portion and an outer diameter portion that are the shafts. And a backup roll bearing device of a rolling element guide type that does not contact the roll. The backup roll bearing device according to any one of claims 1 to 4, wherein the radial bearing is filled with grease of 20 to 40% of a space volume thereof.

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