JP2006177447A - Double-row rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double-row rolling bearing for properly supporting an operating load different between right and left rows, depending on the status of the load in each row. <P>SOLUTION: The double-row rolling bearing 11 comprises an inner ring 12, an outer ring 13, and a ball 14 and a spherical roller 15 arranged as rolling elements in one row and in the other row, respectively. The ball 14 and the spherical roller 15 are held by cages 16, 17, respectively. The inner ring 12 has a raceway groove 12a for receiving the ball and a sectionally circular raceway surface 12b along the outer diameter face of the spherical roller. The raceway surface 13a of the outer ring 13 is in a spherical shape along the outer peripheral face of the spherical roller 15. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a double-row rolling bearing, and more particularly to a double-row rolling bearing in which an uneven load acts on rolling elements in the left and right rows and a support structure including such a bearing.

  As a bearing suitable for rotatably supporting the main shaft of a wind power generator, for example, Japanese Patent Application Laid-Open No. 2004-11737 (Patent Document 1) discloses an example using a self-aligning roller bearing. As disclosed in this publication, a large double row self-aligning roller bearing 1 as shown in FIG. 1 is often used for a main shaft bearing in a large wind power generator.

  Since the main shaft 2 of the wind turbine of the wind power generator is attached to the housing 4 so as to support the tip end side where the blade 3 is provided, the main shaft 2 can normally support the bending of the main shaft 2 as a bearing for the cantilever support. A large spherical roller bearing 1 is used. When the blade 3 receives wind force, the main shaft 2 rotates together with the blade 3. The rotation of the main shaft 2 is increased by a speed increaser (not shown) and transmitted to the generator to generate power.

The self-aligning roller bearing 1 includes an inner ring 5, an outer ring 6, and double-row spherical rollers 7 and 8. When power is generated by receiving wind, the main shaft 2 that supports the blade 3 has an axial load (bearing axial load) caused by the wind force applied to the blade 3 and a radial load (bearing radial load) due to the weight of the shaft and the blade. Be loaded. The double-row self-aligning roller bearing 1 can receive both a radial load and an axial load at the same time, and has a self-aligning property. The bending of the inner main shaft 2 can be absorbed.
JP 2004-11737 A (paragraph number 0002 etc.)

  In the double-row self-aligning roller bearing 1 for supporting the main shaft of the wind power generator described above, the axial load becomes larger than the radial load during the rotation of the wind turbine. In this case, the spherical roller 8 in the row farther from the blade 3 among the double rows of spherical rollers 7 and 8 receives the radial load and the axial load at the same time. The spherical rollers 7 in the row closer to the blade 3 do not receive much axial load, and are exclusively subjected to radial load.

  On the other hand, in a windless state, the load applied to the spindle support bearing 1 is exclusively a radial load. Therefore, the spherical rollers 7 in the row closer to the blade 3 receive a larger radial load when the windmill is not rotating than when the windmill is rotating.

  As described above, in the case of the double row self-aligning roller bearing 1 for supporting the main shaft of the wind power generator, the load on the spherical roller 8 in the row farther from the blade 3 is increased, so that the spherical surface in the row closer to the blade 3 is used. Compared with the roller 7, the rolling fatigue life is shortened. On the other hand, the spherical rollers 7 in the row closer to the blade 3 are lightly loaded, causing slippage between the spherical rollers 7 and the raceway surfaces 5a and 6a of the inner and outer rings 5 and 6, causing surface damage and wear problems. Although it is conceivable to increase the bearing size in order to cope with a large load, the margin becomes too large on the light load side, which is uneconomical.

  The object of the present invention is to provide an appropriate support according to the load condition of each row in an environment where different loads act on the left and right rows, to extend the actual life, and to save the economy of materials. Is to provide a typical double row rolling bearing.

  In addition, reliability is improved by using this bearing in a support structure in which different loads act on the left and right rows, for example, a main shaft support structure of a wind power generator, a helical gear support structure, or a vertical shaft support structure. Is to provide a high and long-life support structure.

  A double-row rolling bearing according to the present invention includes an inner ring having raceway surfaces in left and right rows, an outer ring having a common raceway surface in left and right rows, balls as rolling elements arranged in one row, and the other A double row rolling bearing comprising rollers as rolling elements arranged in a row.

  By setting it as the said structure, the load capacity of the row | line | column which has arrange | positioned the roller can be enlarged. In addition, the row in which the balls are arranged is less likely to slip between the balls and the inner and outer rings even under a light load. As a result, in an environment where different loads are applied to the left and right rows, proper support can be provided according to the load status of each row, so that the real life can be extended and the economical double row with no waste of materials. A rolling bearing is obtained.

  Preferably, the roller is a spherical roller, and the inner ring is a groove in which the raceway surface of one row receives a ball, and the raceway surface of the other row has an arcuate cross section along the outer diameter surface of the spherical roller. The outer ring is a spherical recess whose raceway surface is along the outer diameter surface of the spherical roller. As a result, a double row rolling bearing having alignment with respect to misalignment due to shaft deflection or the like is obtained.

  Preferably, the double-row rolling bearing has a first cage that holds the ball, and a second cage that holds the roller and is rotatable independently of the first cage. As a result, the difference in peripheral speed between the balls can be absorbed and the rotation can be made smooth.

  Further, in the double row rolling bearing, the contact angles of the left and right rows are preferably the same. As a result, a symmetrical standard product can be used for the outer ring, so that the manufacturing cost can be reduced. Furthermore, since the right and left columns can be measured under the same measurement conditions when measuring the accuracy of the outer ring, the measurement work can be performed efficiently.

  A main shaft support structure of a wind power generator according to the present invention includes a blade that receives wind power, a main shaft that is fixed to the blade, and rotates together with the blade, and a double-row rolling that is incorporated in a fixed member and supports the main shaft rotatably. A main shaft support structure of a wind power generator including a bearing. When paying attention to the double row rolling bearing, the inner ring having the raceway surface in the left and right rows, the outer ring having the common raceway surface in the left and right rows, the balls as rolling elements arranged in one row, and the other row It is characterized by comprising a roller as an arranged rolling element.

  With the above configuration, proper support according to the characteristics acting on the main shaft can be performed, so that a main shaft support structure with high reliability and long life can be obtained.

  The helical gear support structure according to the present invention is a helical gear support having a helical gear having a central axis and a double row rolling bearing incorporated in a fixed member and rotatably supporting the central axis. Structure. When paying attention to the double row rolling bearing, the inner ring having the raceway surface in the left and right rows, the outer ring having the common raceway surface in the left and right rows, the balls as rolling elements arranged in one row, and the other row It is characterized by comprising a roller as an arranged rolling element.

  The vertical shaft support structure according to the present invention is a vertical shaft support structure that includes a vertical shaft and a double-row rolling bearing that is incorporated in a fixed member and rotatably supports the vertical shaft. When paying attention to the double row rolling bearing, the inner ring having the raceway surface in the left and right rows, the outer ring having the common raceway surface in the left and right rows, the balls as rolling elements arranged in one row, and the other row It is characterized by comprising a roller as an arranged rolling element.

  In the double row rolling bearing of the present invention, by changing the load capacity between the left and right rows, it is possible to support appropriately according to the load situation of each row in an environment where different loads act on the left and right rows, so that the real life Can be extended, and the material is economical and economical.

  In addition, by using this bearing in a support structure in which different loads act on the left and right rows, for example, a main shaft support structure of a wind power generator, a helical gear support structure, or a vertical shaft support structure, reliability is improved. And a long-life support structure can be obtained.

  With reference to FIG. 2, the double row rolling bearing 11 according to the present invention will be described.

  The double row rolling bearing 11 includes an inner ring 12, an outer ring 13, balls 14 arranged in one row as rolling elements, and spherical rollers 15 arranged in the other row as rolling elements. Ball 14 and spherical roller 15 are held by cages 16 and 17, respectively. The inner ring 12 includes a raceway groove 12 a that receives the ball 14 and a raceway surface 12 b that has an arcuate cross section along the outer diameter surface of the spherical roller 15. The raceway surface 13 a of the outer ring 13 has a spherical shape along the outer peripheral surface of the spherical roller 15. The two cages 16 and 17 can be rotated independently of each other.

  In the double row rolling bearing 11 having the above configuration, the load capacity of the right side bearing 11 b using the spherical roller 15 is higher than that of the left side bearing 11 a using the ball 14.

Further, contact angles θ ₁ and θ ₂ formed by a plane perpendicular to the bearing center axis and a line of action of the resultant force transmitted to the left and right rolling elements 14 and 15 by the inner ring 12 and the outer ring 13 are expressed as θ ₁ <θ _2. Thus, the axial load capacity of the bearings 11b in the right row can be made higher than that in the bearings 11a in the left row.

  In general, ball bearings are less likely to slip between the ball and raceway even under light load conditions compared to roller bearings, so when used in an environment where different loads act on the left and right rows, rolling elements By arranging the left-side row of bearings 11b using the balls 14 on the light load side, appropriate support according to the load state of each row can be performed.

  Further, the ball 14 is excellent in assemblability, productivity, and the like, compared to the spherical roller 15, and the manufacturing cost is low, so that a low-cost bearing can be provided.

  Next, a double row rolling bearing 21 according to another embodiment of the present invention will be described with reference to FIG.

The double-row rolling bearing 21 includes an inner ring 22, an outer ring 23, balls 24 and spherical rollers 25 as rolling elements, and cages 26 and 27. The contact angles θ ₁ and θ ₂ of the left and right rows 21a and 21b of the bearing are the same.

By making the contact angles θ ₁ and θ ₂ of the left and right rows 21a and 21b of the bearings the same as in the above configuration, a symmetric standard product can be used for the outer ring 23, thereby reducing manufacturing costs. Is possible. Furthermore, since the right and left columns can be measured under the same measurement conditions when measuring the accuracy of the outer ring 23, the measurement work can be performed efficiently.

  In each of the embodiments described above, an example in which a roller as a rolling element is a spherical roller has been shown. However, the present invention is not limited to this, and a cylindrical roller or a tapered roller may be used.

  Furthermore, in this case, since the bearing itself cannot be aligned, the outer surface of the outer ring is a convex spherical surface, and the inner surface of the concave spherical surface that receives the outer surface of the outer ring is further outside the outer ring. You may arrange | position the aligning ring which has.

  In addition, the cages for holding the rolling elements in the left and right rows may be integrated, but by absorbing the difference in the peripheral speed between the ball and the spherical roller by allowing the left and right cages to rotate independently. Can do.

  4 and 5 show an example of a main shaft support structure of a wind power generator to which a double-row rolling bearing according to an embodiment of the present invention as shown in FIGS. 2 and 3 is applied. The casing 33 of the nacelle 32 that supports the main components of the spindle support structure is installed on the support base 30 via the swivel bearing 31 at a high position so as to be able to turn horizontally. A main shaft 36 holding a blade 37 at one end is rotatably supported in a casing 33 of the nacelle 32 via a main shaft support bearing 35 incorporated in a bearing housing 34. The other end of the main shaft 36 is connected to a speed increaser 38, and the output shaft of the speed increaser 38 is coupled to the rotor shaft of the generator 39. The nacelle 32 is turned at an arbitrary angle by a turning motor 40 via a speed reducer 41.

  In the illustrated embodiment, two spindle support bearings 35 are installed side by side, but may be one. As the main shaft support bearing 35, a double-row rolling bearing according to an embodiment of the present invention is used.

  In this case, spherical rollers are used as rolling elements in a row far from the blade 37 to which a large load is applied. On the other hand, balls are used as rolling elements in the row closer to the blade 37 where only a radial load is applied. Thereby, since it can support appropriately according to the load condition of each row | line | column, the spindle support structure of the wind generator with high reliability and a long lifetime is obtained.

  Next, an example in which the double-row rolling bearing according to the present invention is applied to a helical gear support structure will be described with reference to FIGS.

  FIG. 6 is a view showing a state in which the helical gear 51 and the helical gear 52 are meshed with each other. In the helical gear, the tooth trace is twisted along the helical line, so that the transmission is extremely smooth, there is little vibration noise, and a large force can be transmitted. Therefore, it is used in an environment where quietness and high torque are required.

  FIG. 7 is a diagram showing a power transmission mechanism in which an input shaft 61 and an output shaft 62 are connected by helical gears 63 and 64, respectively. The output shaft 62 is supported by a double row rolling bearing 65 according to the present invention. The double row rolling bearing 65 includes an inner ring 66, an outer ring 67, balls 68 and spherical rollers 69 as rolling elements, and is fixed to the housing.

  In this power transmission mechanism, when the output shaft 62 rotates clockwise as viewed from the double-row rolling bearing 65 side, the output shaft 62 has a radial component force Fr of the power F transmitted to the helical gear 64, and Axial component force Fa acts.

  In this case, spherical rollers 69 are used as rolling elements in a row far from the helical gear 64 that receives both a radial load and an axial load. Balls 68 are used as rolling elements in the row closer to the helical gear 64 to which only a radial load is mainly applied. As a result, since appropriate support can be performed according to the load condition of each row, a helical gear support structure with high reliability and long life can be obtained.

  Next, an example in which the double-row rolling bearing according to the present invention is applied to a vertical shaft support structure will be described with reference to FIG.

  Referring to FIG. 8, the vertical shaft 71 is supported by a double-row rolling bearing 72 according to the present invention. The double row rolling bearing 72 includes an inner ring 73, an outer ring 74, balls 75 and spherical rollers 76 as rolling elements, and is fixed to the housing. Here, the vertical axis need not be strictly supported in the vertical direction, and includes a case where the vertical axis is supported at a certain angle from the vertical direction.

  In this vertical shaft support structure, the axial load Fa acts on the vertical shaft 71 by its own weight. In this case, spherical rollers 76 are used as rolling elements in the lower row of bearings to which a large load is applied. On the other hand, balls 75 are used as rolling elements in rows above the bearings that are lightly loaded. Thereby, since appropriate support can be performed according to the load condition of each row, a highly reliable and long-life vertical shaft support structure can be obtained.

  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 double-row rolling bearing used in an environment where uneven loads are applied to the left and right rows and a support structure including such a bearing.

It is sectional drawing which shows the prior art example of the spindle support bearing of a wind power generator. It is a double row rolling bearing which concerns on one Embodiment of this invention, Comprising: As a rolling element of a right-and-left row | line | column, it is a figure which shows the state which used the ball for one row | line and the spherical roller for the other row | line. It is a double row rolling bearing according to another embodiment of the present invention, using balls in one row and spherical rollers in the other row as rolling elements in the left and right rows, and the contact angles of the left and right rows are the same. It is a figure which shows the state which carried out. It is a figure which shows an example of the spindle support structure of the wind power generator using the double row rolling bearing which concerns on this invention. FIG. 5 is a schematic side view of the main shaft support structure of the wind power generator shown in FIG. 4. It is a figure which shows the state which meshed | engaged a pair of helical gear. It is a figure which shows an example of the helical gear support structure using the double row rolling bearing which concerns on this invention. It is a figure which shows an example of the vertical shaft support structure using the double row rolling bearing which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Double row self-aligning roller bearing, 2 Wind generator main shaft, 3 Blade, 4 Housing, 5, 12, 22, 66, 73 Inner ring, 5a, 12b Inner ring raceway surface, 12a Inner ring raceway groove, 6, 13, 23, 67, 74 Outer ring, 6a, 13a Outer ring raceway surface, 7, 8, 15, 25, 69, 76 Spherical roller, 14, 24, 68, 75 ball, 11, 21, 65, 72 Double row rolling bearing, 16, 17 , 16, 27 Cage, 30 Support base, 31 Swivel seat bearing, 32 Nacelle, 33 Casing, 34 Bearing housing, 35 Spindle support bearing, 36 Spindle, 37 Blade, 38 Speed increaser, 39 Generator, 40 Turning motor , 41 reducer, 51, 52, 63, 64 helical gear, 61 input shaft, 62 output shaft.

Claims (7)

An inner ring having raceways in the left and right rows;
An outer ring having a common raceway surface in the left and right rows;
A double-row rolling bearing comprising balls as rolling elements arranged in one row and rollers as rolling elements arranged in the other row. The roller is a spherical roller,
The inner ring is a groove in which the raceway surface of one row receives the balls, and the raceway surface of the other row is a raceway surface having an arcuate cross section along the outer diameter surface of the spherical roller,
The double-row rolling bearing according to claim 1, wherein the outer ring is a spherical recess whose raceway surface is along the outer diameter surface of the spherical roller. The double row rolling bearing includes a first cage for holding the ball;
The double row rolling bearing according to claim 1, further comprising a second cage that holds the rollers and is rotatable independently of the first cage.   The double row rolling bearing according to any one of claims 1 to 3, wherein the double row rolling bearing has the same contact angle between the left and right rows. A blade that receives wind,
One end of which is fixed to the blade and rotates with the blade;
In the main shaft support structure of a wind power generator, which is incorporated in a fixed member and includes a double-row rolling bearing that rotatably supports the main shaft,
The double row rolling bearing includes an inner ring having a raceway surface in the left and right rows, an outer ring having a raceway surface common to the left and right rows, balls as rolling elements arranged in one row, and the other row. A main shaft support structure for a wind power generator, comprising a roller as a rolling element. A helical gear having a central axis;
In a helical gear support structure including a double row rolling bearing incorporated in a fixed member and rotatably supporting the central shaft,
The double row rolling bearing includes an inner ring having a raceway surface in the left and right rows, an outer ring having a raceway surface common to the left and right rows, balls as rolling elements arranged in one row, and the other row. A helical gear supporting structure, comprising: a roller as a rolling element. A vertical axis,
In a vertical shaft support structure including a double-row rolling bearing incorporated in a fixed member and rotatably supporting the vertical shaft,
The double row rolling bearing includes an inner ring having a raceway surface in the left and right rows, an outer ring having a raceway surface common to the left and right rows, balls as rolling elements arranged in one row, and the other row. A vertical shaft support structure comprising: a roller as a rolling element.

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