JP2009063101A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rolling bearing comprising an inner ring that is split in the axial direction in which the inner ring can be properly fastened. <P>SOLUTION: A self-aligning roller bearing 31 as the rolling bearing is provided with the inner ring 32 in a form of an annulus ring comprising a plurality of arc-shaped inner ring members combined in the circumferential direction, an outer ring 33, a plurality of spherical-surfaced rollers 34 as rolling elements disposed between the inner ring 32 and the outer ring 33, and a fastening band 36 engaged with the outer diameter surface of the inner ring 32 to fasten the plurality of the inner ring members to one another. When setting the outer diameter size for the inner ring 32 with which the fastening band 36 is engaged as d, the thickness size for the fastening band 36 as h, the modulus of elasticity for the fastening band 36 as E, and a yielding point for the fastening band 36 as σ<SB>y</SB>, h/d≤σ<SB>y</SB>/E is satisfied. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a rolling bearing, and more particularly to a rolling bearing having an inner ring divided in the axial direction.

  Spherical roller bearings are used as bearings used in low-speed and heavy-load environments such as wind power generators, steel, and converter facilities. In addition, since the self-aligning roller bearing used in the above-mentioned application is large, a large number of work steps and a large amount of cost are required to replace the bearing at the time of repair. Then, the self-aligning roller bearing employ | adopted as steel, a converter equipment, etc. is described in Unexamined-Japanese-Patent No. 2002-139032 (patent document 1), for example.

  In the self-aligning roller bearing described in this publication, the inner and outer rings are divided by a plane parallel to the rotation axis (referred to as “dividing in the axial direction”) in order to facilitate repair and replacement. Furthermore, it is described that the inner ring is coupled and integrated by fitting the tightening ring to the fitting portion protruding from both axial ends of the inner ring and tightening with a bolt. This makes it possible to replace only the bearing without removing peripheral parts such as a gear box.

Bearings for main shaft support of wind power generators, like steel and converter facilities, require many man-hours and large costs for bearing replacement. Furthermore, since it is necessary to lower the blade and nacelle to the ground when replacing the bearing, it is also necessary to secure a vast site.
JP 2002-139032 A

  Therefore, when the self-aligning roller bearing configured as described above is adopted as a main shaft support bearing of a wind power generator, a larger axial space than usual is required for the bearing housing. However, since the wind generator has a limited space inside the nacelle, the self-aligning roller bearing having the above configuration cannot be applied as it is.

  Furthermore, the self-aligning roller bearing configured as described above requires a number of parts such as fastening rings, bolts, washers, and detents in addition to the original components of the bearing, making it even more difficult to replace the bearing. I have to.

  Accordingly, an object of the present invention is to provide a rolling bearing in which the inner ring is divided in the axial direction, a rolling bearing capable of appropriately fastening the inner ring, and a main shaft of a wind power generator that employs such a rolling bearing as a main shaft support bearing. It is to provide a support structure.

A rolling bearing according to the present invention includes an annular inner ring formed by connecting a plurality of arc-shaped inner ring members in the circumferential direction, an outer ring, a plurality of rolling elements disposed between the inner ring and the outer ring, and an inner ring. And a ring-shaped fastening band that is fitted to the outer diameter surface and fastens the plurality of inner ring members. When the outer diameter dimension of the inner ring at the position where the fastening band is fitted is d, the thickness dimension of the fastening band is h, the Young's modulus of the fastening band is E, and the yield point of the fastening band is σ _y , h / d ≦ σ _y / E is satisfied.

If the stress applied to the fastening band is set so as not to exceed the yield point σ _y as in the above configuration, it is possible to effectively prevent the fastening band from being plastically deformed when fitted to the inner ring. . Moreover, since this fastening band can fasten an inner ring | wheel only by making it fit to an outer diameter surface, it can reduce a number of parts compared with the former.

  Preferably, a circumferential groove for receiving a fastening band is provided on the outer diameter surface of the inner ring. Thereby, a fastening band can be stably hold | maintained. Moreover, it can prevent effectively that a fastening band interferes with other components, such as a rolling element.

  Preferably, the rolling bearing is formed with a center flange in the axial center portion of the outer diameter surface, a pair of outer flanges at both axial ends, and an inner raceway surface between the center flange and the pair of outer flanges. A double-row spherical roller bearing comprising an inner ring, an outer ring having a spherical outer raceway surface formed on the inner diameter surface, and a spherical roller as a rolling element disposed between the inner raceway surface and the outer raceway surface. is there. And the fastening band is arrange | positioned at the outer-diameter surface of the inside. This eliminates the need to secure a space for disposing the fastening band at the axial end portion of the inner ring, so that the size of the rolling bearing in the axial direction can be reduced as compared with the conventional case.

  More preferably, the fastening band is disposed on the outer diameter surface of the pair of outer casings. The gap generated between the adjacent inner ring members increases as the distance from the fastening position by the fastening band increases. Therefore, in order to suppress the generation of gaps in the entire width direction of the abutting portion, it is desirable to provide fastening bands at a plurality of locations.

  In one embodiment, the fastening band is made of a metal material. According to a metal material such as a general structural rolled steel, the above mathematical formula is satisfied and the strength required for the fastening band can be obtained.

  A main shaft support structure for a wind power generator according to the present invention includes a blade that rotates by receiving wind, a main shaft that supports the blade, and the rolling bearing according to any one of the above that rotatably supports the main shaft. By adopting the rolling bearing with the above configuration, a highly reliable main shaft support structure for a wind power generator can be obtained.

  According to the present invention, it is possible to obtain a rolling bearing capable of appropriately fastening a split inner ring and a main shaft support structure for a wind power generator that employs such a rolling bearing.

  With reference to FIG. 5 and FIG. 6, the wind power generator 11 which employ | adopted the spindle support structure which concerns on one Embodiment of this invention is demonstrated. The wind power generator 11 includes a support 12, a swivel bearing 13, a nacelle 14, a blade 15, a main shaft 16 as a rotation shaft, a speed increaser 17, a generator 18, a bearing housing 19, and a main shaft. A self-aligning roller bearing 31 as a support bearing, a turning motor 20 and a speed reducer 21 are provided.

  The nacelle 14 is installed on the support 12 via a swivel bearing 13 and can be swiveled horizontally by a turning motor 20 and a speed reducer 21. Moreover, it functions as a housing that accommodates the main shaft 16, the speed increaser 17, the power generator 18, the self-aligning roller bearing 31, the turning motor 20, the speed reducer 21, and the like, which are main components of the wind power generator 11.

  The blade 15 is fixed to one end of the main shaft 16 and receives wind to rotate. The main shaft 16 has one end connected to the blade 15 and the other end connected to each of the speed increasers 17, and is rotatably supported by a self-aligning roller bearing 31 incorporated in the bearing housing 19. Then, the rotation of the blade 15 is transmitted to the generator 18 via the speed increaser 17.

  A large axial load is applied to the self-aligning roller bearing 31 by wind force received by the blade 15 and a large radial load is applied by the weight of the blade 15 and the like.

  Therefore, a self-aligning roller bearing 31 as shown in FIGS. 1 and 2 is adopted as a spindle support bearing used in such an environment. 1 is a view showing a self-aligning roller bearing 31 as a rolling bearing according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line II-II in FIG.

  1 and 2, a self-aligning roller bearing 31 is adjacent to an inner ring 32, an outer ring 33, and a plurality of spherical rollers 34 as rolling elements disposed between the inner ring 32 and the outer ring 33. A cage 35 that holds the space between the spherical rollers 34 and a fastening band 36 are provided.

  The inner ring 32 is formed by connecting arc-shaped inner ring members 32a and 32b in the circumferential direction. Further, on the outer diameter surface of the inner ring 32, there is a center collar 32 c at the axial center, a pair of outer collars 32 d and 32 e at both ends in the axial direction, between the middle collar 32 c and the outer collar 32 d, and the middle collar 32 c. Inner raceway surfaces 32f and 32g are respectively formed between the outer casing 32e. Further, circumferential grooves 32h for receiving the fastening bands 36 are formed on the outer diameter surfaces of the intermediate collar 32c and the outer collars 32d and 32e.

  As with the inner ring 32, the outer ring 33 is formed by connecting arc-shaped outer ring members 33 a and 33 b in the circumferential direction. Further, an outer raceway surface 33c constituting a part of a spherical surface is formed on the inner diameter surface of the outer ring 33. Further, like the inner ring 32 and the outer ring 33, the cage 35 is formed by connecting arc-shaped cage segments 35a and 35b in the circumferential direction. Thus, if the inner ring 32, the outer ring 33, and the retainer 35 are divided in the axial direction, it can be incorporated into the main shaft 16 from the radial direction.

  The fastening band 36 is a ring-shaped member made of a metal material such as a general structural rolled steel. Then, the inner ring members 32 a and 32 b are fastened by fitting at least one place on the outer diameter surface of the inner ring 32. In this embodiment, it fits into the circumferential groove 32h of the inner collar 32c and the outer collars 32d, 32e. The fastening band 36 may be fitted to the outer diameter surface of the inner ring 32 while elastically deforming the seamless ring, or the steel band is wound around the outer diameter surface of the inner ring 32 to connect both ends. Also good.

  In the above embodiment, since the cage 35 is guided by the outer diameter surface of the intermediate collar 32c, the circumferential groove prevents the outer diameter surface of the fastening band 36 from protruding from the outer diameter surface of the intermediate collar 32c. It is desirable to set a groove depth of 32h. That is, the groove depth of the circumferential groove 32 h is made deeper than the thickness dimension of the fastening band 36. On the other hand, the outer diameter surface of the fastening band 36 fitted into the outer flanges 32d and 32e may protrude from the outer diameter surfaces of the outer flanges 32d and 32e.

Here, in order to prevent plastic deformation of the fastening band 36 when fitted to the inner ring 32, the following conditions must be satisfied. It should be noted that the outer diameter dimension of the inner ring 32 at the position where the fastening band 36 is fitted is d (mm), the thickness dimension of the fastening band 36 is h (mm), and the diameter (“neutral shaft diameter” in the thickness direction center portion of the fastening band 36 )) Is _dm (mm), the Young's modulus of the fastening band 36 is E (MPa), the yield point of the fastening band 36 is σ _y (MPa), the circumferential strain on the inner surface of the fastening band 36 is ε, and the fastening band The circumferential stress on the inner diameter surface of 36 is σ (MPa).

First, the neutral axis diameter _{d m is} expressed by d m = d + h. Then, the circumferential strain ε is represented by the following formula (1), and the circumferential stress σ is represented by the following formula (2).

Here, in order to prevent plastic deformation of the fastening band 36, it is a condition that the circumferential stress σ does not exceed the yield point σ _y . Therefore, when the equation (2) is substituted into σ _y ≧ σ and transformed, the following equation (3) is obtained.

Here, since E >> σ _y , if σ _y is omitted from the denominator of the right side of Equation (3), h / d ≦ σ _y / E. That is, plastic deformation can be prevented by forming the fastening band 36 with a material and dimensions that satisfy this relationship.

For example, when the fastening band 36 is formed of a material having a Young's modulus E = 208000 (MPa) and a yield point σ _y = 240 (MPa), the dimensions are set so as to satisfy h / d ≦ 1.15 × 10 ^−3. Need to be set.

  Next, consider the case where the fastening band 36 is fitted to the outer flange of 22211 which is the minimum model number of the self-aligning roller bearing with a flange. Since the outer diameter of the outer flange of this self-aligning roller bearing is d = 69.6 (mm), in order to prevent plastic deformation of the fastening band 36, the thickness dimension h ≦ 0.080 of the fastening band 36. (Mm).

  On the other hand, the thickness dimension of the conventional fastening ring employed in the above self-aligning roller bearing (22211) is about 7.7 mm. When such a fastening ring is fitted to the intermediate flange 32c and / or the outer flanges 32d, 32e, the spherical roller 34 and the retainer 35 are interfered and the smooth rotation of the bearing is inhibited. From this point of view, it is desirable to employ the fastening band 36 that satisfies the above relational expression.

  In the above embodiment, the example in which the fastening band 36 is disposed on the outer diameter surface of each of the intermediate collar 32c and the outer collars 32d and 32e has been described. However, the present invention is not limited thereto, and at least one of these is provided. The effect of the present invention can be obtained if the fastening band 36 is disposed only in the case.

  For example, if the fastening band 36 is provided only on the intermediate collar 32c, it is not necessary to secure a space for providing the fastening band 36 at both axial ends of the inner ring 32. Thereby, the axial size of the self-aligning roller bearing 31 can be further reduced.

  However, the gap generated between the adjacent inner ring members 32 a and 32 b increases as the distance from the fastening position by the fastening band 36 increases. Therefore, in order to suppress the generation of gaps in the entire width direction of the abutting portion, it is desirable to provide the fastening bands 36 at a plurality of locations.

  In the above embodiment, the inner ring 32 is provided with the intermediate collar 32c and the outer collars 32d, 32e. However, these are not essential components of the present invention and can be omitted. With reference to FIG. 3 and FIG. 4, self-aligning roller bearings 41 and 51 according to other embodiments of the present invention will be described. In addition, the same reference number is attached | subjected to a common component, and description is abbreviate | omitted.

  First, referring to FIG. 3, in the inner ring 42 employed in the self-aligning roller bearing 41, a guide ring 47 is disposed between the double-row inner raceway surfaces 42f and 42g in place of the intermediate collar. Since the guide wheel 47 rotates while being guided by the outer diameter surface of the inner ring 42, the fastening band 36 disposed between the double row inner raceway surfaces 42 f and 42 g does not protrude from the outer diameter surface of the inner ring 42. It is desirable to make it.

  Further, both end portions in the axial direction of the inner ring 42 function as guide surfaces for guiding the rotation of the retainer 45 by omitting the outer rod. Therefore, it is desirable that the fastening bands 36 disposed at both axial ends of the inner ring 42 do not protrude from the outer diameter surface of the inner ring 42. Next, referring to FIG. 4, the self-aligning roller bearing 51 also omits the guide wheels between the double-row inner raceways 42f and 42g.

  In each of the above embodiments, an example of the self-aligning roller bearing 31 is shown as a rolling bearing that supports the main shaft 16 of the wind power generator 11. However, the present invention is not limited to this, and a tapered roller bearing, a cylindrical roller bearing, Whether the rolling contact surface is a single row or a double row, regardless of whether the rolling elements are rollers or balls, such as needle roller bearings, deep groove ball bearings, angular contact ball bearings, and 4-point contact ball bearings Regardless, any rolling bearing in which the inner ring is divided in the axial direction can be employed.

  Furthermore, in the above embodiment, an example in which the present invention is applied to the main shaft support structure of a wind power generator has been shown. However, the present invention is not limited to this, and the present invention is also applied to a rolling bearing used for other purposes. It is possible.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The present invention is advantageously used for a rolling bearing having an inner ring divided in the axial direction.

It is a figure which shows the rolling bearing which concerns on one Embodiment of this invention. It is sectional drawing in II-II of FIG. It is a figure which shows the rolling bearing which concerns on other embodiment of this invention. It is a figure which shows the rolling bearing which concerns on further another embodiment of this invention. It is a figure which shows the wind power generator which employ | adopted the rolling bearing of FIG. FIG. 6 is a schematic side view of the wind power generator shown in FIG. 5.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 Wind generator, 12 Support base, 13 Swivel seat bearing, 14 Nacelle, 15 Blade, 16 Main shaft, 17 Gearbox, 18 Generator, 19 Bearing housing, 20 Swing motor, 21 Reducer, 31, 41, 51 Automatic Spherical roller bearings, 32, 42 inner ring, 32a, 32b inner ring member, 32c intermediate flange, 32d, 32e outer flange, 32f, 32g, 42f, 42g inner raceway, 32h circumferential groove, 33 outer ring, 33a outer raceway, 34 Spherical roller, 35, 45 Cage, 35a, 35b Cage segment, 36 Fastening band.

Claims (6)

An annular inner ring formed by connecting a plurality of arc-shaped inner ring members in the circumferential direction;
Outer ring,
A plurality of rolling elements disposed between the inner ring and the outer ring;
A ring-shaped fastening band that fits to the outer diameter surface of the inner ring and fastens the plurality of inner ring members;
If the outer diameter dimension of the inner ring at the position where the fastening band is fitted is d, the thickness dimension of the fastening band is h, the Young's modulus of the fastening band is E, and the yield point of the fastening band is σ _y ,
h / d ≦ σ _y / E
Meet the rolling bearing.   The rolling bearing according to claim 1, wherein a circumferential groove for receiving the fastening band is provided on an outer diameter surface of the inner ring. The rolling bearing is
An inner ring in which an inner raceway surface is formed between each of the center rod and the pair of outer rods, and a pair of outer rods at both axial end portions,
The outer ring having a spherical outer raceway surface formed on the inner diameter surface;
A double row spherical roller bearing comprising a spherical roller as the rolling element disposed between the inner raceway surface and the outer raceway surface,
The rolling bearing according to claim 1, wherein the fastening band is disposed on an outer diameter surface of a middle collar.   The rolling bearing according to claim 3, wherein the fastening band is further disposed on an outer diameter surface of the pair of outer casings.   The rolling bearing according to claim 1, wherein the fastening band is made of a metal material. A blade that rotates in response to the wind;
A main shaft supporting the blade;
A main shaft support structure for a wind power generator, comprising the rolling bearing according to any one of claims 1 to 5 that rotatably supports the main shaft.

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