JP4699827B2 - Main shaft support structure for tapered roller bearing and wind power generator - Google Patents

Description

  The present invention relates to a tapered roller bearing and a main shaft support structure of a wind power generator, and more particularly, a tapered roller bearing capable of receiving a large radial load, thrust load, and moment load, and a main shaft support of a wind power generator using such a bearing. Concerning structure.

  The bearing used for the main shaft of the wind power generator needs to receive a radial load against the weight of the blade, a thrust load against the wind force, and a moment load. Furthermore, since the main shaft of a wind power generator has a cantilever beam structure, a bearing having self-alignment with respect to the deflection of the main shaft is required, and therefore, a combination of a self-aligning roller bearing and a cylindrical roller bearing is used. It was. FIG. 5 is a schematic view when the self-aligning roller bearing 101 is used as a main shaft of a wind power generator. Referring to FIG. 5, the self-aligning roller bearing 101 holds an inner ring 102, a plurality of aligning rollers 103 a and 103 b arranged in the left and right rows, and a plurality of aligning rollers 103 a and 103 b. A container 104 and an outer ring 105. The self-aligning roller bearing 101 is mounted on a main shaft 112 provided with a blade 111 for receiving wind at one end, and is incorporated in a housing 113. The self-aligning roller bearing 101 and the cylindrical roller bearing thus mounted are combined and used for the main shaft of the wind power generator.

  However, a bearing that combines the above-mentioned two rolling bearings has a large number of parts and is required to be reduced. Moreover, it is requested | required also about size reduction of a bearing.

  In response to such demands, a double-row tapered roller bearing that can receive a large thrust load and radial load with a single bearing is inferior in alignment to a self-aligning roller bearing. Is used. FIG. 6 is an example of a cross-sectional view of the double row tapered roller bearing 121. Referring to FIG. 6, double-row tapered roller bearing 121 includes left and right inner rings 122a and 122b arranged so that the end surfaces on the small diameter side face each other, inner ring spacers 128 arranged between inner rings 122a and 122b, and outer rings. 124, a plurality of tapered rollers 123a, 123b disposed between the inner rings 122a, 122b and the outer ring 124, and left and right cages for holding the intervals between the plurality of tapered rollers 123a, 123b in the left and right rows.

  For each cage, a pin type cage that can hold more tapered rollers 123a and 123b is used in order to realize a load capacity against a large radial load. The pin type cage holds the ends of the pins 125a and 125b penetrating the tapered rollers 123a and 123b and the plurality of pins 125a and 125b protruding from the large end surfaces of the tapered rollers 123a and 123b, and extends in an annular shape. Large-diameter side plates 126a and 126b, and small-diameter side plates 127a and 127b that hold the other ends of the plurality of pins 125a and 125b protruding toward the small end surfaces of the tapered rollers 123a and 123b and extend annularly.

Further, a double row tapered roller bearing using such a pin type cage is disclosed in Japanese Patent Laid-Open No. 2003-49843 (Patent Document 1), and a wind turbine for wind power generation using the double row tapered roller bearing as a main shaft. Is disclosed in Japanese Patent Laying-Open No. 2005-105917 (Patent Document 2).
JP 2003-49843 A (paragraph numbers 0008 to 0009, FIG. 1) Japanese Patent Laying-Open No. 2005-105917 (paragraph numbers 0020 to 0039, FIG. 2)

  In order to obtain a larger amount of power generation, the blade 111 needs to receive a larger wind. Under such circumstances, the bearing that supports the main shaft receives a larger radial load, thrust load, and moment load. In order to receive a larger radial load, it is necessary to make the roller lengths of the tapered rollers 123a and 123b of the double-row tapered roller bearing 121 as large as possible. Further, in order to receive a larger thrust load and moment load, it is necessary to increase a contact angle that is an angle formed by the outer ring raceway surface and the rotation axis of the double row tapered roller bearing 121.

  FIG. 7 is a sectional view of the double-row tapered roller bearing 121 when the contact angle is increased. Referring to FIG. 7, when the contact angle α, which is the angle formed between the outer ring raceway surface 131 and the rotation axis (not shown) of the double row tapered roller bearing 121, is increased, the arrow Y of the large collar 133b of the inner ring 122b The thickness in the direction of will be reduced. The same applies to the large collar 133a of the inner ring 122a.

  Here, since the tapered roller 123b is guided by the large end surface to the large collar surface 134b of the inner ring 122b in contact with the large end surface of the tapered roller 123b, a load is applied in the direction of arrow Y in FIG. Specifically, for example, when an external force such as a radial load, a thrust load, or a moment load is applied to the outer ring 124, the component force is transmitted to the large collar surface 134b of the inner ring 122b via the tapered roller 123b. Become. In such a case, a large bending stress is applied to the large collar 133b in the direction of the arrow Z around the thin groove 135b provided at the intersection of the large collar surface 134b and the raceway surface. There is a risk that the large spear 133b, which has become thin and has reduced rigidity, may crack or chip.

  Here, it is possible to shorten the roller length to secure the wall thickness of the large flange 133b in the direction of the arrow Y that is the load acting direction, but from the viewpoint of maintaining the rigidity against the radial load as described above. The roller lengths of the tapered rollers 123a and 123b cannot be shortened.

  An object of the present invention is to provide a tapered roller bearing that does not cause the inner ring to be cracked or chipped, and a main shaft support structure for a wind power generator using such a bearing.

  A tapered roller bearing according to the present invention includes an outer ring, an inner ring, a plurality of tapered rollers disposed between the outer ring and the inner ring, and a cage that holds a space between the plurality of tapered rollers. Here, the above-described inner ring is provided with a slope portion between a large collar surface in contact with the large end face of the tapered roller and a large collar outer diameter surface.

  By providing such a slope portion, the thickness of the large bowl in the load acting direction is increased, and the rigidity of the large bowl in the load acting direction can be increased.

  Preferably, the slope portion forms a truncated cone-shaped surface, and the generatrix thereof extends along the direction of the central axis of the tapered roller. By comprising in this way, the thickness of the direction which is easy to receive a load with respect to a load action direction can be increased with a simple structure.

  More preferably, when the thickness dimension from the inner diameter surface of the inner ring to the maximum outer diameter position of the large collar surface is A and the thickness dimension from the inner diameter surface of the inner ring to the outer diameter surface of the large collar is B, The relationship of B ≧ 1.05A is established, and more preferably, the relationship of B ≦ 1.20A is established.

  By comprising in this way, the thickness which maintains the minimum rigidity which does not have a possibility that a big crack may be cracked or chipped can be ensured. In addition, the amount of increase in wall thickness can be made appropriate in consideration of other dimensions such as the maximum outer diameter of the inner ring.

  More preferably, the diameter of the pitch circle on the large end face side of the tapered roller is equal to the diameter of the outer diameter surface of the large collar. By carrying out like this, a tapered roller can be rolled more stably. Here, “equal” means that the value of the diameter of the pitch circle on the large end face side of the tapered roller is approximately approximate to the value of the diameter of the outer diameter surface of the large collar.

  In another aspect of the present invention, the main shaft support structure of the wind power generator includes a blade that receives wind power, one end of which is fixed to the blade, the main shaft that rotates together with the blade, and a fixed member that can rotate the main shaft. A main shaft support structure of a wind power generator having a tapered roller bearing to be supported. The above-mentioned tapered roller bearing includes an outer ring, an inner ring, a plurality of tapered rollers disposed between the outer ring and the inner ring, and a cage that holds the intervals between the plurality of tapered rollers. Here, the above-described inner ring is provided with a slope portion between a large collar surface in contact with the large end face of the tapered roller and a large collar outer diameter surface.

  By configuring in this way, the rigidity of the large cage in the load acting direction is increased, and the contact angle can be increased without the possibility of cracking or chipping of the inner race, so that a larger thrust load and Can receive moment load.

  According to the present invention, since the slope portion is provided between the large collar surface and the large collar outer diameter surface of the inner ring, the thickness of the large collar relative to the load acting direction is increased, and the rigidity of the large collar is increased. Can give. As a result, there is no fear that the inner ring is cracked or chipped, the contact angle can be increased, and a larger thrust load can be received.

  In addition, if such a tapered roller bearing is used for the main shaft of a wind power generator, the contact angle can be increased without the possibility of cracking or chipping the inner ring, so a larger thrust load and moment load. Can receive.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an inner ring 12b included in a double row tapered roller bearing 11 when the tapered roller bearing according to an embodiment of the present invention is used in a double row. Referring to FIG. 1, inner ring 12b has a large flange 21b for guiding the large end face of the tapered roller, a small flange 22b for guiding the small end face of the tapered roller, and a raceway surface 23b for rolling the tapered roller.

  The inner ring 12b is in contact with the large end surface of the tapered roller and between the large collar surface 27b that guides the large end surface and the large collar outer diameter surface 26b that is the outer diameter surface on the large collar 21b side of the inner ring 12b. In addition, a slope portion 28b that is continuous in the circumferential direction is provided. Here, the slope portion 28b refers to an inclination provided between the large collar surface 27b and the large collar outer diameter surface 26b, and is an area that appears by increasing the thickness of the large collar 21b in the direction of arrow Y. Say. In this case, the slope portion 28b may be configured by a number of surfaces instead of a single surface, or may be configured by a gently curved surface. A chamfer such as a C surface or an R surface is chamfered at the boundary portion X between the large collar surface 27b and the slope portion 28b.

  An arrow is applied to the large collar surface 27b of the inner ring 12b when an external force such as a radial load, a thrust load, or a moment load is applied via a tapered roller (not shown), or when the internal axial clearance is negative. A load is applied in the Y direction. Further, with respect to the load in the direction of the arrow Y, a large bending stress is also applied in the direction of the arrow Z with respect to the large collar 21b, centering on the thin groove 24b. However, since the large collar 21b is provided with the inclined surface portion 28b, the thickness of the large collar 21b is increased in the direction of the arrow Y, which is the direction of the load, so that the rigidity of the large collar 21b can be increased. Moreover, it does not crack or chip with respect to a large bending stress in the direction of arrow Z.

  By configuring in this way, a sufficient thickness is maintained to maintain the rigidity against the load and bending stress on the large collar 21b when an external force such as a radial load, a thrust load, and a moment load is applied. The large bowl 21b is not cracked or chipped. Therefore, the contact angle of the double-row tapered roller bearing including the inner ring 12b can be increased without fear of the large flange 21b being cracked or chipped, and a larger thrust load can be received.

  In addition, about the dimension of the slope part 28b, let A be the thickness dimension from the inner diameter surface 25b of the inner ring 12b, which is a surface in contact with the rotating shaft (not shown), to the maximum outer diameter position of the large collar surface 27b, and the inner diameter. When the thickness dimension from the surface 25b to the large outer diameter surface 26b is B, the relationship of B ≧ 1.05A is established, and more preferably, the relationship of B ≦ 1.20A is established.

  When B is 1.05 A or less, the thickness to maintain the rigidity of the large flange 21b against the load on the large flange 21b or the bending stress when an external force such as a radial load, a thrust load, or a moment load is applied. It cannot be secured sufficiently, and there is a possibility that the large bowl 21b may be cracked or chipped. Further, if B is 1.20 A or more, there is a possibility that the large outer diameter surface 26b is larger than the allowable maximum outer diameter in the dimensional relationship of the inner ring 12b.

  More preferably, in the tapered roller bearing incorporating the inner ring 12b, the diameter of the pitch circle on the large end face side of the tapered roller, which will be described later, is made equal to the diameter of the large flange outer diameter surface 26b of the inner ring 12b. By carrying out like this, it can be set as more optimal wall thickness. Here, the pitch circle refers to a circle drawn when the center of the large end face of the tapered roller rotates around the rotation axis when viewed from the axial direction.

  FIG. 2 is a sectional view showing the double row tapered roller bearing 11 when the tapered roller bearing including the inner ring 12b shown in FIG. 1 is used in a double row. Referring to FIG. 2, double-row tapered roller bearing 11 includes left and right inner rings 12 a and 12 b arranged so that the end surfaces on the small diameter side face each other, and an inner ring spacer 18 arranged between left and right inner rings 12 a and 12 b. The outer ring 14 having a raceway corresponding to the left and right inner rings 12a, 12b, the plurality of tapered rollers 13a, 13b disposed between the inner rings 12a, 12b and the outer ring 14, and the plurality of tapered rollers 13a in the left and right rows, And left and right cages that hold a distance of 13b. Here, the inner ring 12a disposed so as to face the inner ring 12b has the same configuration as the inner ring 12b, and a slope portion 28a is provided between the large collar surface 27a and the large collar outer diameter surface 26a of the inner ring 12a. Yes.

  Since the inner rings 12a and 12b receive a large thrust load and moment load, a contact angle that is an angle formed between the outer ring raceway surface and the rotation axis (not shown) of the double row tapered roller bearing 11 is configured to be large. Preferably, the contact angle is set within a range of 40 ° to 47 °.

  An inner ring spacer 18 having a shape capable of avoiding interference with the small-diameter side plates 17a and 17b is disposed between the inner rings 12a and 12b. Both end surfaces of the inner ring spacer 18 are in contact with the small-diameter side end surfaces of the left and right inner rings 12a and 12b, respectively. When the bearing is assembled or when an external force such as a radial load, a thrust load, or a moment load is applied, the inner ring spacer 18 Pressure is applied from the inner rings 12a, 12b. Therefore, the inner ring spacer 18 needs to be rigid enough to withstand the pressure. In order to ensure rigidity, it is necessary to increase the radial thickness of the inner ring spacer 18, for example, by increasing the radial sectional area of the central portion of the inner ring spacer 18.

  The outer ring 14 has a cross-sectional shape whose central portion is convex in the radial direction, and holds a plurality of tapered rollers 13a and 13b between the inner rings 12a and 12b. In the present embodiment, one outer ring 14 is configured, but separate outer rings may be provided for the inner rings 12a and 12b, respectively.

  The tapered rollers 13a and 13b are disposed between the outer ring 14 and the inner rings 12a and 12b. Further, in order to enable holding by a pin type cage described later, the tapered rollers 13a and 13b are provided with through holes for inserting pins from the small end surface to the large end surface.

  As the cage, a pin type cage that can hold more tapered rollers 13a and 13b is used. Each of the left and right cages includes a pin 15a, 15b that passes through each of the tapered rollers 13a, 13b, and a small-diameter side plate that holds one end of the plurality of pins 15a, 15b protruding toward the small end surface of each of the tapered rollers 13a, 13b. 17a, 17b and large-diameter side plates 16a, 16b that hold the other ends of the plurality of pins 15a, 15b protruding to the large end face side of the tapered rollers 13a, 13b.

  Here, the slope portions 28a and 28b may form a truncated cone shape, and the generatrix thereof may extend along the direction of the central axes 19a and 19b of the tapered rollers 13a and 13b. By doing so, the thickness of the large bowls 21a and 21b can be increased in the direction in which the load is easily received. Further, in assembling the double row tapered roller bearing 11 including the inner rings 12a and 12b, it is possible to avoid interference between the large flanges 21a and 21b and the large-diameter side plates 16a and 16b. In this case, the central axis lines 19a and 19b and the bus line may be parallel, or the mutual lines may have a slight angle.

  Each of the small-diameter side plates 17a and 17b and the large-diameter side plates 16a and 16b extends annularly around the rotation axis of the double row tapered roller bearing 11, and has a ring shape. The small-diameter side plates 17a and 17b are disposed on the small flange side of the inner rings 12a and 12b, and the inner diameter is smaller than the large-diameter side plates 16a and 16b disposed on the large collar side. In addition, the small-diameter side plates 17a and 17b and the large-diameter side plates 16a and 16b both hold a large amount of pins 15a and 15b, and therefore need a certain rigidity. From the viewpoint of rigidity, productivity, and the like, it is preferable that the cross-sectional shapes of the small-diameter side plates 17a and 17b and the large-diameter side plates 16a and 16b are rectangular. Here, there is no particular problem even if the small-diameter side plates 17a and 17b and the large-diameter side plates 16a and 16b have other shapes such as a circular shape and an elliptical shape as long as rigidity can be ensured.

  In particular, the large-diameter side plates 16a and 16b are located close to the inclined surface portions 28a and 28b when the double row tapered roller bearing 11 is assembled. Therefore, when the slope portions 28a and 28b have an angle in the direction in which the large-diameter side plates 16a and 16b exist, the large-diameter side plates 16a and 16b and the slope portions 28a and 28b may interfere with each other. In such a case, even if the large-diameter side plates 16a and 16b are slightly deformed, for example, a relief portion is provided at the interference portion of the large-diameter side plates 16a and 16b so as not to interfere with the slope portions 28a and 28b. Good.

  In the previous embodiment, the pin type cage is used as the cage for holding the tapered rollers 13a and 13b. However, the present invention is not limited to this, and a press cage, a molded cage, a kneading cage, etc. are used. May be. By configuring in this way, it is possible to configure the double-row tapered roller bearing 11 by selecting an optimal cage according to the application.

  In the previous embodiment, the double row tapered roller bearing 11 includes the inner ring spacer 18. However, the present invention is not limited to this, and the inner ring spacer 18 is not provided, and extends in the axial direction from the inner ring of the inner ring. The inner rings 12a and 12b may be provided with inner ring butting portions that come into contact with the small-diameter side end surface of the inner ring. By comprising in this way, the member which comprises the double row tapered roller bearing 11 can be reduced.

  In the previous embodiment, the double-row tapered roller bearing has been described as the tapered roller bearing according to the embodiment of the present invention, but not limited thereto, a plurality of single-row tapered roller bearings are used, In the case where the tapered roller bearings are used in combination, the same applies to the case where a single row tapered roller bearing is used alone. Specifically, the single-row tapered roller bearing includes an outer ring, an inner ring, a plurality of tapered rollers disposed between the outer ring and the inner ring, and a cage that holds a space between the plurality of tapered rollers, The inner ring is provided with a slope portion between a large collar surface in contact with the large end surface of the tapered roller and a large collar outer diameter surface.

  3 and 4 show an example of a main shaft support structure of a wind power generator in which the above-described tapered roller bearing is applied as a main shaft support bearing 35. FIG. 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 a swivel bearing 31 at a high position so as to be able to turn horizontally. A main shaft 36 that fixes a blade 37 that receives wind power to 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. Is connected to the 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 the turning motor 40 via the speed reducer 41.

  The main shaft support bearing 35 incorporated in the bearing housing 34 is a double row tapered roller bearing when the tapered roller bearing according to one embodiment of the present invention is used in a double row, and the outer ring faces the end surface on the small diameter side. Left and right inner rings, inner ring spacers arranged between the left and right inner rings, a plurality of tapered rollers arranged between the outer ring and the left and right inner rings, and a plurality of tapered rollers in the left and right rows And left and right cages for holding the gap. Each of the cages described above includes a pin that passes through each tapered roller, a small-diameter side plate that extends annularly while holding one end of a plurality of pins protruding to the small end surface side of each tapered roller, and a large end surface side of each tapered roller And a large-diameter side plate extending annularly while holding the other ends of the plurality of pins projecting. Here, each of the inner rings described above is provided with a slope portion between the large collar surface in contact with the large end face of the tapered roller and the large collar outer diameter surface.

  By making the main shaft support bearing 35 into a double-row tapered roller bearing having such a configuration, the thickness of the large collar can be increased, so that the large diameter of the inner ring is not cracked or chipped, and the contact angle is increased. It can be increased and can receive larger thrust loads and moment loads. As a result, it is possible to provide a main shaft support structure for a wind power generator that can receive larger thrust loads and moment loads.

  In this case as well, a double row tapered roller bearing was used as the main shaft support bearing used in the main shaft support structure according to the embodiment of the present invention, but not limited to this, a plurality of single row tapered roller bearings were used, The tapered roller bearings may be used in combination, or a single row tapered roller bearing may be used alone.

  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 main shaft support structure of the tapered roller bearing and the wind power generator according to the present invention can increase the contact angle without cracking or chipping the inner ring, so that particularly large radial load, thrust load, moment It can be effectively used for a tapered roller bearing and a main shaft support structure of a wind power generator.

It is sectional drawing which shows the inner ring | wheel 12b contained in the double row tapered roller bearing 11 at the time of using the tapered roller bearing which concerns on one Embodiment of this invention as a double row tapered roller bearing. It is sectional drawing of the double row tapered roller bearing 11 containing the inner ring | wheel 12b shown in FIG. It is a figure which shows an example of the spindle support structure of the wind power generator concerning one Embodiment of this invention. FIG. 4 is a schematic side view of the main shaft support structure of the wind power generator shown in FIG. 3. It is the schematic at the time of using the self-aligning roller bearing 101 for the main axis | shaft of a wind power generator. It is sectional drawing which shows an example of the conventional double row tapered roller bearing 121. It is sectional drawing which shows the double row tapered roller bearing 121 in the case of the conventional large contact angle.

Explanation of symbols

  11 Double row tapered roller bearing, 12a, 12b Inner ring, 13a, 13b Tapered roller, 14 Outer ring, 15a, 15b Pin, 16a, 16b Large diameter side plate, 17a, 17b Small diameter side plate, 18 Inner ring spacer, 19a, 19b Center Axis line, 21a, 21b, large surface, 22b, small surface, 23b raceway surface, 24b fillet groove, 25b inner surface, 26a, 26b large surface, 27a, 27b large surface, 28a, 28b slope, 30 support base 31 bearing seat, 32 nacelle, 33 casing, 34 bearing housing, 35 spindle support bearing, 36 spindle, 37 blade, 38 speed increaser, 39 generator, 40 motor for turning, 41 speed reducer.

Claims (6)

A tapered roller bearing comprising an outer ring, an inner ring, a plurality of tapered rollers disposed between the outer ring and the inner ring, and a retainer that holds a space between the plurality of tapered rollers,
The contact angle, which is the angle formed by the outer ring raceway surface and the rotational axis of the tapered roller bearing, is 40 ° or more,
The inner ring has a thickness dimension from the inner diameter surface of the inner ring to the maximum outer diameter position of the large collar surface between the large collar surface in contact with the large end surface of the tapered roller and the large collar outer diameter surface. When the thickness dimension from the inner diameter surface of the inner ring to the outer diameter surface of the large collar is B, the thickness of the large collar is increased in the load acting direction so that B is larger than A. A tapered roller bearing with a slope. The tapered roller bearing according to claim 1, wherein the inclined surface portion forms a truncated cone-shaped surface, and a generatrix thereof extends along a central axis direction of the tapered roller. When the thickness dimension from the inner diameter surface of the inner ring to the maximum outer diameter position of the large collar surface is A, and the thickness dimension from the inner diameter surface of the inner ring to the outer diameter surface of the large collar is B,
The tapered roller bearing according to claim 1, wherein a relationship of B ≧ 1.05 A is established. In the dimensional relationship,
The tapered roller bearing according to claim 1, wherein a relationship of B ≦ 1.20 A is established. The tapered roller bearing according to any one of claims 1 to 4, wherein a diameter of a pitch circle on a large end surface side of the tapered roller is equal to a diameter of the outer diameter surface of the large collar. A blade that receives wind,
One end of which is fixed to the blade and rotates with the blade;
A main shaft support structure for a wind power generator, which is incorporated in a fixed member and has a tapered roller bearing that rotatably supports the main shaft,
The tapered roller bearing includes an outer ring, an inner ring, a plurality of tapered rollers disposed between the outer ring and the inner ring, and a cage that holds a space between the plurality of tapered rollers,
The contact angle, which is the angle formed by the outer ring raceway surface and the rotational axis of the tapered roller bearing, is 40 ° or more,
The inner ring has a thickness dimension from the inner diameter surface of the inner ring to the maximum outer diameter position of the large collar surface between the large collar surface in contact with the large end surface of the tapered roller and the large collar outer diameter surface. When the thickness dimension from the inner diameter surface of the inner ring to the outer diameter surface of the large collar is B, the thickness of the large collar is increased in the load acting direction so that B is larger than A. Main shaft support structure for wind power generators with a slope.

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