JP2005321078A - Roller bearing and rolling bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a roller bearing easy of assembling work and easy to incorporate into a device such as a spindle although it has seals. <P>SOLUTION: The double row cylindrical roller bearing 10 comprises an inner ring 1 having collars 7, 7 at both axial ends, an outer ring 2 having no collar, two-row cylindrical rollers 3, cages 4, 4, the seals 5, 5, and grease filled in a bearing space. The seals 5, 5 are mounted on the inner ring 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a roller bearing and a rolling bearing device in which the roller bearing is incorporated.

Many conventional roller bearings include a collar on the inner ring and a seal attached to the outer ring. Such a roller bearing cannot be assembled in a state where the seal is attached to the outer ring because the seal part interferes when the inner ring is inserted into the inner peripheral surface of the outer ring. Therefore, in many cases, after the inner ring is inserted into the outer ring and assembled, a roller bearing is completed by attaching a seal to the outer ring. In some cases, a method of attaching a seal for sealing the roller bearing to a member other than the roller bearing is used.
JP 11-166544 A JP-A-6-50346

However, such a method has a problem that the assembling work of the roller bearing or the work of assembling the roller bearing into a device such as a spindle becomes complicated, leading to an increase in cost. In addition, there is a method in which a seal is not attached to the roller bearing. However, since the roller bearing is not sealed, there is a possibility that inconvenience that grease leaks out or foreign matter enters.
Accordingly, the present invention provides a roller bearing that solves the above-described problems of the prior art and that is easy to assemble and that can be easily incorporated into a device such as a spindle despite having a seal. The task is to do. It is another object of the present invention to provide a rolling bearing device that is easy to incorporate a rolling bearing and has excellent rotational accuracy.

In order to solve the above problems, the present invention has the following configuration. That is, the roller bearing of claim 1 according to the present invention is a roller bearing comprising an inner ring, an outer ring, and a plurality of rollers arranged to be freely rollable between the inner ring and the outer ring. One of the outer rings has a collar at both ends in the axial direction, and the other bearing ring does not have a collar or has a collar only at one end in the axial direction, and the inner ring and the outer ring Of these, a seal is attached to the bearing ring having the flanges at both ends in the axial direction.
With such a configuration, the roller bearing can be assembled by inserting and fitting the inner ring with the seal and the roller into the inner peripheral surface of the outer ring, so that the roller bearing can be easily assembled. Moreover, it is easy to incorporate into a device such as a spindle.

According to a second aspect of the present invention, the roller bearing includes an inner ring, an outer ring, a plurality of cylindrical rollers disposed between the inner ring and the outer ring so as to freely roll, and the inner ring and the outer ring. A roller bearing having a cylindrical roller, wherein the inner ring has collars at both ends in the axial direction, and the outer ring does not have collars or has a collar only at one end in the axial direction. And a seal is attached to the inner ring.
With such a configuration, the roller bearing can be assembled by inserting and fitting the inner ring with the seal, the roller, and the cage into the inner peripheral surface of the outer ring, so that the roller bearing can be easily assembled. It is. Moreover, it is easy to incorporate into a device such as a spindle.

Furthermore, the roller bearing according to claim 3 of the present invention is the roller bearing according to claim 2, wherein the roller bearing is a double row roller bearing, and the cage is a circle continuous in a circumferential direction of the inner ring and the outer ring. A roller-guided comb-shaped cage comprising an annular portion and a plurality of column portions protruding in the axial direction from the annular portion, wherein the annular portion is in the vicinity of axial ends of the inner ring and the outer ring. It is arranged.
With such a configuration, since the seal serves as a stopper, the cage is prevented from falling off the roller bearing.

Furthermore, a roller bearing according to a fourth aspect of the present invention is the roller bearing according to the second or third aspect, wherein the cage and the seal can contact each other, and at least one of the cage and the seal A sliding resistance reducing film is formed on the contact portion.
With such a configuration, wear and heat generation due to contact between the seal and the cage are suppressed. As a result, the deterioration of the grease is suppressed, so that the roller bearing is not easily seized or damaged.

Furthermore, a roller bearing according to a fifth aspect of the present invention is the roller bearing according to any one of the first to fourth aspects, having a radial clearance of 10 μm or more and an inner diameter surface of the inner ring having a tapered shape. It is characterized by.
When the inner diameter surface of the inner ring is tapered, the size of the radial clearance can be easily adjusted when a roller bearing is incorporated into a device such as a spindle.

Furthermore, the rolling bearing device according to claim 6 of the present invention is a housing, a shaft inserted in the housing, and interposed between the housing and the shaft so as to relatively rotate the housing and the shaft. A rolling bearing device comprising a freely supporting rolling bearing, wherein the rolling bearing is the roller bearing according to claim 5, and the rolling bearing is incorporated so that a radial clearance is 10 μm or less. Features.
The rolling bearing device having such a configuration is easy to incorporate the rolling bearing and has excellent rotational accuracy.

Furthermore, the rolling bearing according to claim 7 of the present invention is rotatably disposed between a rotatable rotating wheel, a fixed wheel that rotatably supports the rotating wheel, and the rotating wheel and the fixed wheel. A plurality of rolling elements, a seal attached to the rotating wheel and interposed between the rotating wheel and the fixed wheel, and grease enclosed in a space surrounded by the rotating wheel, the fixed wheel, and the seal And the seal has a shape such that a distal end portion closer to the fixed ring is positioned outward in the axial direction than a proximal end portion attached to the rotating wheel. And
With such a configuration, the grease is easily held in the space surrounded by the rotating wheel, the fixed wheel, and the seal.

  As described above, the roller bearing of the present invention is easy to assemble in spite of having a seal, and can be easily incorporated into a device such as a spindle. Moreover, the rolling bearing device of the present invention is easy to incorporate the rolling bearing and has excellent rotational accuracy. Furthermore, the rolling bearing of the present invention is easy to retain grease.

DESCRIPTION OF EMBODIMENTS Embodiments of a roller bearing and a rolling bearing device according to the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals.
[First embodiment]
FIG. 1 is a partial longitudinal sectional view showing the structure of a double row cylindrical roller bearing which is an embodiment of a roller bearing according to the present invention.
A double-row cylindrical roller bearing 10 in FIG. 1 includes an inner ring 1, an outer ring 2, two rows of cylindrical rollers 3 that are rotatably arranged between the inner ring 1 and the outer ring 2, and each row of cylindrical rollers 3. The holders 4 and 4 are respectively held, and the seals 5 and 5 are attached to the inner ring 1 and interposed between the inner ring 1 and the outer ring 2. The inner ring 1, the outer ring 2, and the seals 5 and 5 Grease (not shown) is sealed in the enclosed bearing space.

At both axial ends of the outer peripheral surface of the inner ring 1, collars 7 and 7 are provided projecting radially outward, and at the central portion of the outer peripheral surface of the inner ring 1 in the axial direction, the intermediate collar 8 is radially outward. It protrudes toward the direction. The outer ring 2 is not provided with a collar.
In such a double-row cylindrical roller bearing 10, since the seal 5 is provided on the inner ring 1 having the collar 7, the seal 5, the cylindrical roller 3, and the cage are kept without interference between the seal 5 and the cylindrical roller 3. 4 can be assembled by inserting and fitting the inner ring 1 with the inner ring 1 into the inner peripheral surface of the outer ring 2. Therefore, the assembly work of the double row cylindrical roller bearing 10 is easy. Further, it is easy to incorporate the double-row cylindrical roller bearing 10 into a device such as a spindle.

  The cage 4 is a roller guide type comb-shaped cage. The annular portion 4a is continuous in the circumferential direction of the double row cylindrical roller bearing 10, and the axial direction of the double row cylindrical roller bearing 10 from the annular portion 4a. The plurality of pillar portions 4b, 4b,... Projecting from each other, and the plurality of pillar portions 4b are arranged at equal intervals in the circumferential direction. And the cylindrical roller 3 is rotatably held by the pocket 4c formed between each pillar part 4b.

  The double row cylindrical roller bearing 10 is provided with two cages 4 for holding the two rows of cylindrical rollers 3. As can be seen from FIG. 1, the annular portion 4a has a double row cylindrical roller bearing. 10 is arranged in the vicinity of the axial end portion, and the annular portion 4a of the retainer 4 and the seal 5 can be opposed to each other. In such a configuration, the seal 5 positioned axially outward from the cage 4 serves as a stopper for the cage 4, so that no retaining portion is provided as in the roller bearing shown in the reference diagram of FIG. 2. However, the cage 4 is prevented from falling off from the double-row cylindrical roller bearing 10.

  As can be seen from FIG. 2, the retaining portion is provided on the inner peripheral surface of the cage so as to protrude radially inward, and the collar surface of the collar (surface substantially perpendicular to the axial direction for guiding and holding the cylindrical roller). The movement of the cage in the axial direction is restricted by engaging with the. If the retaining portion is not provided and there is no contact between the retaining portion and the collar surface, the torque can be kept small even at high speed rotation of dmN 1 million or more.

  Further, when the retaining portion and the collar surface come into contact with each other, there is a risk of adversely affecting the roller behavior (roller inclination, etc.). However, in the contact between the annular portion 4a of the cage 4 and the seal 5, The adverse effect on the behavior of is less likely to occur. At this time, since the cage 4 is a roller guide type, the adverse effect due to the contact between the cage and the guide surface is less likely to occur than in the case of the raceway guide type guided by the outer surface of the inner ring or the inner surface of the outer ring The rotational fluctuation of the cage is suppressed.

  When the annular portion 4a of the cage 4 and the seal 5 are in contact with each other, the portion of the annular portion 4a of the cage 4 that contacts the seal 5 and the circle of the seal 5 It is preferable to form a sliding resistance reducing film (not shown) on at least one of the portions in contact with the ring portion 4a. By doing so, the sliding resistance of the contact portion is reduced, so that wear and heat generation due to contact between the seal 5 and the cage 4 are suppressed even during high-speed rotation of dmN 1 million or more, and deterioration of grease is suppressed. Therefore, the double row cylindrical roller bearing 10 is hardly seized or damaged.

  The type of the sliding resistance reducing film is not particularly limited as long as the sliding resistance can be reduced when the annular portion 4a of the cage 4 and the seal 5 come into contact with each other. A diamond-like carbon film) or a fluororesin film is preferable. In the case of forming a diamond-like carbon film, it is preferable to first form an intermediate layer made of titanium, silicon or the like as a base, and then form a diamond-like carbon film thereon.

  Furthermore, the double row cylindrical roller bearing 10 has a radial clearance of 10 μm or more. When such a double-row cylindrical roller bearing 10 is incorporated in a rotating device such as a spindle, the radial clearance of the double-row cylindrical roller bearing 10 is adjusted to 10 μm or less in order to increase the rotational accuracy of the rotating device. Incorporation is preferred. At this time, if the inner surface 1a of the inner ring 1 fitted to the shaft of a rotating device such as a spindle has a tapered shape as shown in FIG. 1, the double-row cylindrical roller bearing 10 is incorporated into the rotating device such as the spindle. The size of the radial clearance can be easily adjusted.

  That is, the radial ring, which is 10 μm or more, is adjusted to 0 μm by attaching the outer ring 2 of the double-row cylindrical roller bearing 10 to the spindle housing, attaching the inner ring 1 to the spindle shaft, and tightening the inner ring 1 and the shaft. ing. However, it is most preferable if the radial clearance can be adjusted to 0 μm, but considering the tolerance, it is preferably 10 μm or less, more preferably 5 μm or less, and further preferably 3 μm or less. In addition, if the adjustment is aimed at 0 μm, a negative clearance may occur, but in order to prevent an increase in the rotational torque of the spindle, the lower limit of the negative clearance is −5 μm, and a more preferable lower limit is −3 μm. It is.

Such adjustment of the radial clearance can be performed more easily when the inner ring has a collar than when the outer ring has a collar.
In addition, this embodiment shows an example of this invention and this invention is not limited to this embodiment. For example, in the present embodiment, the cage 4 is disposed so that the annular portion 4a is positioned in the vicinity of the end portion in the axial direction of the double row cylindrical roller bearing 10, but as in the roller bearing of FIG. You may arrange | position so that the annular part 4a of the two holder | retainers 4 may oppose.

The material of the cage 4 is not particularly limited, and may be a metal material such as a copper alloy. However, a resin material is preferable in consideration of generation of wear powder, mass, workability, and the like. A preferred example is polyphenylene sulfide resin containing carbon fiber.
Furthermore, in the present embodiment, a double-row cylindrical roller bearing has been described as an example of a roller bearing, but the present invention is not limited to a double-row roller bearing, and is also applicable to a single-row roller bearing as shown in FIG. can do. Moreover, it can apply not only to a cylindrical roller bearing but to various types of other roller bearings. For example, tapered roller bearings, self-aligning roller bearings, and needle roller bearings. However, when it is applied to a cylindrical roller bearing that is often used at high speed rotation, the effect can be obtained higher.

[Second Embodiment]
The present invention relates to a rolling bearing, and more particularly to a rolling bearing that is lubricated with a small amount of grease and used at high speed.
Machine tools are becoming more and more rigid and high-speed spindles due to demands for improved machining efficiency. Therefore, the speed of rolling bearings (especially cylindrical roller bearings) used for supporting the main shaft in machine tools is also increasing. The rolling bearing that supports the spindle of the machine tool is filled with grease in order to suppress abnormal heat generation during operation, and the radial clearance is adjusted when it is incorporated into the spindle.

At this time, if the amount of grease charged is too large, a large amount of heat is generated due to the stirring resistance of the grease during the initial running-in operation, which may cause excessive preload or seizure and damage the rolling bearing. In addition, if foreign matter is mixed in when the grease is sealed, the oil film is cut between the race and the rolling elements, and a large amount of frictional heat is generated, which may cause seizure early.
Accordingly, an object of the present invention is to solve the problems of the conventional rolling bearing as described above, and to provide a rolling bearing having a long life that is unlikely to cause damage such as seizure.

In order to solve the above problems, the present invention has the following configuration. That is, a rolling bearing according to the present invention includes a rotatable rotating wheel, a fixed wheel that rotatably supports the rotating wheel, and a plurality of rolling elements that are arranged between the rotating wheel and the fixed wheel so as to be freely rotatable. A moving body, a seal attached to the rotating wheel and interposed between the rotating wheel and the fixed wheel, and a grease enclosed in a space surrounded by the rotating wheel, the fixed wheel, and the seal. In the rolling bearing, the seal has a shape such that a distal end portion closer to the fixed ring is positioned outward in the axial direction than a proximal end portion attached to the rotating wheel.
With such a configuration, the grease is easily held in the space surrounded by the rotating wheel, the fixed wheel, and the seal.

Embodiments of a rolling bearing according to the present invention will be described in detail with reference to the drawings. FIG. 4 is a partial longitudinal sectional view showing the structure of a double row cylindrical roller bearing which is an embodiment of the rolling bearing according to the present invention.
A double row cylindrical roller bearing 10 of FIG. 4 includes an inner ring 1 (rotating ring), an outer ring 2 (fixed ring), and two rows of cylindrical rollers 3 arranged between the inner ring 1 and the outer ring 2 so as to be freely rotatable. The holders 4 and 4 for holding the cylindrical rollers 3 in each row, and the seals 5 and 5 attached to the inner ring 1 and interposed between the inner ring 1 and the outer ring 2, are formed as an inner ring 1 and an outer ring. 2, and a bearing space surrounded by the seals 5 and 5 are filled with grease (not shown).

At both axial ends of the outer peripheral surface of the inner ring 1, collars 7 and 7 are provided projecting radially outward, and at the central portion of the outer peripheral surface of the inner ring 1 in the axial direction, the intermediate collar 8 is radially outward. It protrudes toward the direction. The outer ring 2 is not provided with a collar.
This cage 4 is a roller guide type comb-shaped cage. An annular portion 4a continuous in the circumferential direction of the double row cylindrical roller bearing 10 and an axial direction of the double row cylindrical roller bearing 10 from the annular portion 4a. A plurality of projecting column parts 4b, 4b,..., And the plurality of column parts 4b are arranged at equal intervals in the circumferential direction. And the cylindrical roller 3 is rotatably held by the pocket 4c formed between each pillar part 4b.

The double-row cylindrical roller bearing 10 is provided with two cages 4 for holding the two rows of cylindrical rollers 3. As can be seen from FIG. 4, the two cages 4 are provided with an annular portion 4a. Are arranged to face each other.
Further, the seal 5 has a shape such that the distal end portion 5b closer to the outer ring 2 is positioned outwardly in the axial direction of the double-row cylindrical roller bearing 10 than the base end portion 5a attached to the inner ring 1. When the double-row cylindrical roller bearing 10 is rotated, the inner ring 1 that is a rotating wheel rotates. However, the centrifugal force due to the rotation acts on the grease, and the grease moves outward in the radial direction of the double-row cylindrical roller bearing 10. At this time, since the seal 5 has the shape as described above, the grease moved outward in the radial direction is easily held in the bearing space.

Therefore, since sufficient lubrication can be performed with a small amount of grease, heat generation due to grease stirring resistance is unlikely to occur during initial break-in operation. Therefore, excessive preload and seizure are unlikely to occur, and the rolling bearing is not easily damaged.
If the tip portion 5b is positioned axially outward of the double row cylindrical roller bearing 10 rather than the base end portion 5a, the cross-sectional shape of the seal 5 is bent as shown in FIG. It may be in the shape of a straight line or curved.

  Further, when the cage 4 is a comb cage, a space in which grease can easily move is secured in the bearing space. Further, the cylindrical rollers 3 are not held in all the pockets of the cage 4 but, for example, the cylindrical rollers 3 are held at one or more intervals, and the cylindrical rollers 3 are not held in some pockets. If this is done (ie, there are empty pockets), more space for the grease to move is secured. Thus, if the space where the grease is easy to move is secured, heat generation due to the grease stirring resistance is further suppressed.

  In order to newly manufacture a cage with the required number of pockets, it is necessary to prepare a new mold in the case of a resin cage, but the rollers are held in some pockets as described above. By doing so, since the existing cage can be used, it is economical because it is not necessary to prepare a new mold. In addition, a cage with a small number of pockets increases the thickness of the annular portion and the column portion, and increases the amount of resin required, resulting in an increase in cost.

In addition, this embodiment shows an example of this invention and this invention is not limited to this embodiment. For example, the cage 4 may be arranged so that the annular portions 4a of the two cages 4 face each other, but the annular portion 4a is positioned in the vicinity of the axial end of the double row cylindrical roller bearing 10. May be arranged.
Moreover, when it arrange | positions so that the annular part 4a may be located in the axial direction edge part vicinity of the double row cylindrical roller bearing 10, it is the same as that of 1st embodiment in the contact part of the holder | retainer 4 and the seal | sticker 5. A sliding resistance reducing film may be formed.

Further, similarly to the first embodiment, the double row cylindrical roller bearing 10 may have a radial clearance of 10 μm or more, and the inner diameter surface of the inner ring 1 may have a tapered shape. As in the first embodiment, the double row cylindrical roller bearing 10 is preferably incorporated into a rotating device such as a spindle so that the radial clearance is 10 μm or less.
Furthermore, the material of the cage 4 is not particularly limited, and may be a metal material such as a copper alloy, but a resin material is preferable in consideration of generation of wear powder, mass, workability, etc. A preferred example is polyphenylene sulfide resin containing carbon fiber.

Furthermore, in the present embodiment, a double-row cylindrical roller bearing has been described as an example of a roller bearing, but the present invention is not limited to a double-row roller bearing, and is also applicable to a single-row roller bearing as shown in FIG. can do. Moreover, it can apply not only to a cylindrical roller bearing but to various types of other roller bearings. For example, tapered roller bearings, self-aligning roller bearings, and needle roller bearings. However, when it is applied to a cylindrical roller bearing that is often used at high speed rotation, the effect can be obtained higher.
The rolling bearing of the present invention can be applied to a rolling bearing that requires low heat generation, such as a main shaft of a machine tool, even though it is lubricated with a small amount of lubricant and used at high speed.

It is a fragmentary longitudinal cross-section which shows the structure of the double row cylindrical roller bearing which is one Embodiment of the roller bearing which concerns on this invention. It is a fragmentary longitudinal cross-sectional view of the cylindrical roller bearing which has a holder | retainer provided with the retaining part. It is a fragmentary longitudinal cross-section which shows the structure of the single row cylindrical roller bearing which is another embodiment of the roller bearing which concerns on this invention. It is a fragmentary longitudinal cross-section which shows the structure of the double row cylindrical roller bearing which is one Embodiment of the rolling bearing which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inner ring 1a Inner surface 2 Outer ring 3 Cylindrical roller 4 Cage 4a Annular part 4b Pillar part 4c Pocket 5 Seal 5a Base end part 5b Tip part 7 Brim 8 Middle collar 10 Double row cylindrical roller bearing

Claims (7)

In a roller bearing comprising an inner ring, an outer ring, and a plurality of rollers arranged to roll between the inner ring and the outer ring,
One of the inner ring and the outer ring has a collar at both ends in the axial direction, and the other bearing ring does not have a collar or has a collar only at one end in the axial direction,
A roller bearing, wherein a seal is attached to a raceway having a flange at both axial ends of the inner ring and the outer ring. In a roller bearing comprising: an inner ring; an outer ring; a plurality of cylindrical rollers arranged to roll between the inner ring and the outer ring; and a cage that holds the cylindrical rollers between the inner ring and the outer ring. ,
The inner ring has collars at both axial ends, and the outer ring has no collars or has a collar only at one axial end,
A roller bearing, wherein a seal is attached to the inner ring.   A roller guide that is a double row roller bearing, and the cage includes an annular portion that is continuous in a circumferential direction of the inner ring and the outer ring, and a plurality of column portions that protrude in the axial direction from the annular portion. The roller bearing according to claim 2, wherein the roller bearing is a comb-shaped cage of the type, and the annular portion is arranged in the vicinity of axial end portions of the inner ring and the outer ring.   The said cage and the said seal | sticker can contact, The sliding resistance reduction film | membrane is formed in the contact part of at least one of the said cage | basket and the said seal | sticker, The Claim 2 or Claim 3 characterized by the above-mentioned. Roller bearings.   The roller bearing according to any one of claims 1 to 4, wherein the roller bearing has a radial clearance of 10 µm or more, and an inner diameter surface of the inner ring is tapered. In a rolling bearing device comprising: a housing; a shaft inserted into the housing; and a rolling bearing interposed between the housing and the shaft to support the housing and the shaft so as to be relatively rotatable.
The rolling bearing device according to claim 5, wherein the rolling bearing is incorporated so that a radial clearance is 10 μm or less. A rotatable wheel, a fixed wheel that rotatably supports the rotating wheel, a plurality of rolling elements that are rotatably arranged between the rotating wheel and the fixed wheel, and the rotating wheel that is attached to the rotating wheel In a rolling bearing comprising: a seal interposed between a rotating wheel and the fixed wheel; and grease enclosed in a space surrounded by the rotating wheel, the fixed wheel, and the seal,
The rolling bearing according to claim 1, wherein the seal has a shape such that a distal end portion closer to the fixed ring is positioned outward in the axial direction than a proximal end portion attached to the rotating wheel.

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