JP2012141011A - Turning ring bearing structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turning ring bearing structure which is configured to maintain excellent bearing performance by adjustment and change of rigidity which restrains an increase in weight to minimum in order to prevent contact pressure disturbance due to structural deformation from being adversely influenced to the bearing performance.SOLUTION: The turning ring bearing 10A of a roller bearing is so configured as to interpose rolling elements 13 between track rings 14, 15 formed on an inner ring 11 and an outer ring 12A and is used as a turning ring bearing structure which has in a peripheral direction region with a high bearing contact pressure, a rigidity reinforced part 20A which enhances the rigidities of the inner ring 11 and/or the outer ring 12A higher than those in the surroundings thereof.

Description

  The present invention relates to a slewing ring bearing structure of a rolling bearing suitable for, for example, a nacelle yaw driving device and a wind turbine blade pitch driving device.

A wind power generator (hereinafter also referred to as “windmill”) 1 shown in FIG. 14 is driven by rotating a rotor head 4 having windmill blades 5 by receiving wind force, and increasing the speed of the rotation by a speed increaser. It is a device that generates electricity with a generator.
In such a wind turbine generator 1, the rotor head 4 provided with the wind turbine blades 5 is connected to the speed increaser and the generator in the nacelle 3 installed at the upper part of the tower 2 via the main shaft. It is necessary to match the direction of the head 4 with the changing wind direction (make the rotor rotation surface face the wind direction).

For this reason, for example, in the upwind type wind power generator 1, the nacelle 3 is yaw-turned on the tower 2 (turned in the direction of arrow Rn on a substantially horizontal plane) to receive wind from the front of the rotor head 4. For this reason, a yaw driving device is provided as a device for yawing the nacelle 3 with respect to the tower 2.
Further, since each wind turbine blade 5 needs to change the pitch angle in response to changes in wind speed or the like, as a device for turning the wind turbine blade 5 in the direction of the arrow Rw with respect to the rotor head 4, for each wind turbine blade. A pitch drive is provided.

In the yaw driving device and the pitch driving device described above, for example, the slewing ring bearing 10 configured as shown on the left side of FIG. 15 is adopted as the slewing ring bearing for the windmill that supports the nacelle 3 and the windmill blade 5 so as to be capable of turning. ing. The slewing ring bearing 10 is a rolling bearing having a configuration in which a rolling element 13 is disposed between an inner ring 11 and an outer ring 12, and is a mechanical element that supports relative rotation on the inner ring 11 side and the outer ring 12 side. .
Further, the slewing ring bearing 10 for wind turbines and the like is designed based on the maximum surface pressure. A general slewing ring bearing 10 including the above-described slewing ring bearing for windmills, particularly a large slewing ring bearing such as a slewing ring bearing for windmills, is a tower 2, a nacelle 3 and a rotor on which the slewing ring bearing 10 is installed. In the structure such as the head 4, the inner ring 11 and the outer ring 12 are also used as a part of the strength member constituting the structure.

For this reason, if the slewing ring bearing 10 does not have sufficient rigidity, the bearing performance is adversely affected, for example, the surface pressure distribution is disturbed by the influence of the surrounding structural deformation.
FIG. 16 shows the relationship between the presence / absence of structural deformation and the surface pressure of a slewing ring bearing provided with two upper and lower rolling elements 13. According to this figure, the surface pressure distribution when there is no structural deformation depicts a substantially semicircular arc shape, but when there is structural deformation, the surface pressure distribution that causes a large disturbance in the substantially semicircular arc shape. Distribution. The horizontal axis in FIG. 16 is the angle in the circumferential direction. In the following description, the vertical direction of the rolling element 13 is the upper stage on the nacelle 3 side when the slewing ring bearing 10 is used in a yaw drive device, and When the lower stage is the tower 2 side and the slewing wheel bearing 10 is used for the pitch drive device, the upper stage is the blade tip side of the wind turbine blade 5 and the lower stage is the blade root side attached to the rotor head 4.

FIG. 17 shows a structural modification example when the slewing ring bearing 10 receives an external force, and the inner ring 11 and the outer ring 12 are deformed differently depending on the direction of the external force F indicated by an arrow in the drawing.
17A is an external force input example when the inner ring 11 and the outer ring 12 are deformed into an elliptical shape, and FIG. 17B is an external force input example when the inner ring 11 and the outer ring 12 are bent in the axial direction. 17 (c) shows an external force input example when the inner ring 11 and the outer ring 12 are deformed in the direction in which the space between the inner ring 11 and the outer ring 12 widens.

  In such a slewing ring bearing (rolling bearing) 10, for example, as disclosed in Patent Document 1 below, in order to prevent deformation due to external force and maintain uniform surface pressure, a fixed portion of the bearing is used. Techniques have been proposed to increase the rigidity.

JP 2010-23665 A

  By the way, when the above-described slewing ring bearing 10 for a windmill or the like receives a load, if the inner ring 11 or the outer ring 12 is also deformed by the influence of the surrounding structural deformation, the surface pressure distribution acting on the rolling element 13 is disturbed. In some cases, only a part of the surface pressure is locally increased. For example, in the surface pressure distribution shown in FIG. 16, when comparing the case of the upper stage bearing, which is one of the rolling elements 13 arranged in the upper and lower stages, with structural deformation and without structural deformation, a substantially semicircular arc shape is obtained. The maximum surface pressure with structural deformation is higher in the vicinity of an angle of 90 degrees than the maximum surface pressure without structural deformation.

  As a measure for eliminating such disturbance of the surface pressure distribution, for example, a slewing ring bearing 10 ′ shown on the right side of FIG. 15 may increase the size of the inner ring 11 ′ and the outer ring 12 ′ in order to ensure rigidity. Conceivable. However, in the case of the slewing ring bearing 10 used in the yaw drive device or pitch drive device of the wind power generator 1, since it is a component installed on the upper part of the tower 2, increasing the physique causes the increase in weight. Therefore, it is not preferable. In particular, the recent wind power generators 1 tend to be large in order to obtain a large output. Therefore, in order to reduce the burden on the tower 2, the weight of the nacelle 3 and the rotor head 4 including the swivel bearing 10 can be reduced. Has become a major issue.

  The present invention has been made in order to solve the above-described problems, and the object of the present invention is to increase the weight in order to prevent the disturbance of the surface pressure distribution accompanying the structural deformation from adversely affecting the bearing performance. An object of the present invention is to provide a slewing ring bearing structure capable of maintaining good bearing performance by adjusting and changing rigidity to a minimum.

In order to solve the above problems, the present invention employs the following means.
A slewing ring bearing structure according to claim 1 of the present invention is a slewing ring bearing structure of a rolling bearing in which rolling elements are sandwiched between race rings formed on an inner ring and an outer ring, and the inner ring and / or the outer ring The present invention is characterized in that a rigidity-enhanced portion having higher rigidity than the surroundings is provided in a circumferential region where the bearing surface pressure is high.

  According to such a slewing ring bearing structure, since the rigidity-enhanced portion in which the rigidity of the inner ring and / or outer ring is increased from the surroundings is provided in the circumferential region where the bearing surface pressure is high, the rigidity of the inner ring and outer ring is changed to the bearing surface pressure. Accordingly, by changing in the circumferential direction, it is possible to minimize the increase in weight and to eliminate the disturbance in the surface pressure distribution. In other words, the rigidity-enhanced portion of the inner ring or outer ring is set to have a partly high rigidity with respect to the circumferential region where the bearing surface pressure is high and is easily deformed. Has no rigidity-enhancing portion that causes an increase in weight. Therefore, it is possible to suppress the weight of the entire slewing ring bearing while maintaining the bearing performance.

In the above-described slewing ring bearing structure, it is preferable that the rigidity enhancing portion is a wide portion in which the inner diameter of the inner ring and / or the outer diameter of the outer ring is a non-circular shape. In other words, the wide part of the inner ring is a rigidity-enhanced part in which the inner ring width in plan view is increased (the cross-sectional area is increased) by reducing the inner diameter, and the wide part of the outer ring is viewed in plan view by increasing the outer diameter. This is a rigidity-enhanced part in which the outer ring width is increased (the cross-sectional area is increased).
In this case, the wide part may have a trapezoidal axial cross-sectional shape. In other words, the cross-sectional shape of the wide part is rigid with a minimum increase in weight if it is trapezoidal with a long side on the top side that receives bearing surface pressure and a short side on the bottom side parallel to the top side. (Cross sectional area) can be increased, and the disturbance generated in the surface pressure distribution can be eliminated.

In the slewing ring bearing structure, the rigidity reinforcing portion may include a reinforcing member attached to the outer peripheral surface of the outer ring and / or the inner peripheral surface of the inner ring. Such a reinforcing member can change the rigidity of the inner ring and the outer ring in the circumferential direction in accordance with the bearing surface pressure. Therefore, it is possible to eliminate the disturbance generated in the surface pressure distribution while minimizing the increase in weight.
Examples of the reinforcing member described above include a rib and a reinforcing plate provided on the outer peripheral surface of the outer ring and the inner peripheral surface of the inner ring. Note that the cross-sectional shape of the reinforcing plate may be one in which the plate pressure is changed according to the bearing surface pressure.
Further, the reinforcing member described above may be partially attached to the upper surface side in the vertical direction so as to increase the rigidity of the upper surface side that receives the bearing surface pressure.

  A slewing ring bearing structure according to a fifth aspect of the present invention is a slewing ring bearing structure of a rolling bearing in which a rolling element is sandwiched between race rings formed on an inner ring and an outer ring, and the rolling element is not loaded when the load is applied. The initial contact angle in contact with the surface of the raceway is set by changing in the circumferential direction so as to reduce the maximum surface pressure during load application and structural deformation.

  According to such a slewing ring bearing structure, the initial contact angle at which the rolling element contacts the surface of the raceway ring when no load is applied is set by changing in the circumferential direction so as to reduce the load load and the maximum surface pressure during structural deformation. Therefore, when the contact angle changes greatly upon receiving a load, it is possible to prevent the contact ellipse from climbing on the edge portion and causing the surface pressure to rapidly increase. That is, the initial contact angle, which was constant in the circumferential direction, changes in the circumferential direction so as to reduce the maximum surface pressure during load application and structural deformation, so that the contact ellipse is edged even when subjected to a load during operation. Therefore, it is possible to prevent a sudden increase in the contact pressure by suppressing the change in the contact angle to be small.

  A slewing ring bearing structure according to claim 6 of the present invention is a slewing ring bearing structure of a rolling bearing in which a rolling element is sandwiched between raceways formed on an inner ring and an outer ring, and a groove radius of the raceway ring is set as follows. It is characterized in that it is set by changing in the circumferential direction so as to reduce the maximum surface pressure at the time of load load and structural deformation.

  According to such a slewing ring bearing structure, the groove radius of the bearing ring is set by changing in the circumferential direction so as to reduce the maximum surface pressure during load application and structural deformation. The pressure can be suppressed, and the increase in bearing torque can be minimized. In other words, the groove radius of the bearing ring, which was constant in the circumferential direction, has changed in the circumferential direction so as to reduce the load load and the maximum surface pressure during structural deformation. The relationship (ratio) between the diameter of the moving body and the groove radius of the race is optimized, and the maximum surface pressure and bearing torque can be suppressed.

According to the above-described slewing ring bearing structure of the present invention, by adjusting and changing the rigidity while minimizing the increase in weight, it is possible to prevent the disturbance of the surface pressure distribution accompanying the structural deformation from adversely affecting the bearing performance. Good bearing performance can be maintained.
Further, by optimizing the initial contact angle and the groove radius of the bearing ring by appropriately changing them in the circumferential direction, it becomes possible to prevent the surface pressure from rapidly increasing or to suppress the maximum surface pressure and the bearing torque.

It is a figure which shows 1st Embodiment about the turning ring bearing structure which concerns on this invention, (a) is a top view, (b) is AA sectional drawing of (a). It is a figure which shows the 1st modification of the turning ring bearing structure which concerns on 1st Embodiment, (a) is a top view, (b) is BB sectional drawing of (a). It is a figure which shows the 2nd modification of the turning ring bearing structure which concerns on 1st Embodiment, (a) is a top view, (b) is CC sectional drawing of (a). It is a figure which shows the 3rd modification of the turning ring bearing structure which concerns on 1st Embodiment, (a) is a top view, (b) is DD sectional drawing of (a). It is a figure which shows the 4th modification of the turning ring bearing structure which concerns on 1st Embodiment, (a) is a top view, (b) is EE sectional drawing of (a). It is a figure which shows the 5th modification of the turning ring bearing structure which concerns on 1st Embodiment, (a) is a top view, (b) is FF sectional drawing of (a), (c) is the 1st of a reinforcement member. This is a modification. It is sectional drawing which attached the reinforcement member of the 2nd modification about the turning ring bearing structure of the 6th modification shown in FIG. It is sectional drawing for description which shows a standard state about the contact angle of the rolling element clamped between the bearing rings. It is a figure for demonstrating the problem resulting from a normal initial contact angle, (a) shows the contact ellipse and surface pressure distribution of a normal state, (b) is the contact ellipse of the state which received the influence of structural deformation. And the surface pressure distribution. It is a figure which shows 2nd Embodiment about the turning ring bearing structure which concerns on this invention, and is explanatory drawing which shows the example of a setting which changed the initial contact angle to the circumferential direction. It is explanatory drawing which shows the suppression effect of the maximum surface pressure about the case where it sets to a normal initial contact angle, and the case where an initial contact angle is changed to the circumferential direction. It is a figure which shows 3rd Embodiment about the turning ring bearing structure which concerns on this invention, and is explanatory drawing which shows the example of a setting which changed the curvature to the circumferential direction. It is explanatory drawing which shows the suppression effect of the maximum surface pressure about the case where it sets to a normal groove curvature, and the case where a groove curvature is changed to the circumferential direction. It is a perspective view which shows the outline | summary of a wind power generator. It is explanatory drawing which shows the rigidity ensuring by the conventional slewing ring bearing (rolling bearing) structure and physique change. It is a figure which shows the difference in the surface pressure distribution (surface pressure which changes according to the circumferential direction angle) by the presence or absence of structural deformation. The structural modification example when an external force is applied to the turning wheel is shown, (a) is an external force input example when the inner ring and the outer ring are deformed into an ellipse, and (b) is a case where the inner ring and the outer ring are bent in the axial direction. (C) shows an external force input example in the case of deformation in the direction in which the space between the inner ring and the outer ring expands.

Hereinafter, an embodiment of a slewing ring bearing structure according to the present invention will be described with reference to the drawings.
The slewing ring bearing structure according to the present embodiment is a rolling bearing applied to a yaw driving device or a pitch driving device in a wind power generator 1 as shown in FIG. 14, for example. A rolling bearing is a mechanical element having a configuration in which raceways having a substantially semicircular cross-sectional shape are formed on opposing surfaces of an inner ring and an outer ring, and rolling elements such as bearings are sandwiched between the raceways.

The yaw drive device of the wind turbine generator 1 is a device that turns the nacelle 3 according to the wind direction at the upper end of the tower 2 so as to receive wind from the front of the rotor head 4. That is, in the yaw drive device, a swirl ring bearing interposed between the upper end portion of the tower 2 and the lower surface of the nacelle 3 supports the nacelle 3 at the upper end portion of the tower 2 so as to be capable of yaw turning. In this case, the upper stage side of the slewing ring bearing is the nacelle 3 side, and the lower stage side is the tower 2 side. Therefore, the vertical direction of the slewing ring bearing is the axial direction, and the horizontal direction is the radial direction.
The pitch driving device of the wind turbine generator 1 is a device for turning the wind turbine blade 5 with respect to the rotor head 4 in order to adjust the pitch angle of each wind turbine blade 5 attached to the rotor head 4 in accordance with changes in wind speed or the like. It is. In other words, in the pitch driving device, the swirl ring bearing interposed between the root (lower end) of the wind turbine blade 5 and the rotor head 4 can swivel (pitch angle adjustment) the wind turbine blade 5 with respect to the rotor head 4. I support it. In this case, the upper stage side of the slewing ring bearing is the tip side of the wind turbine blade 5 and the lower stage side is the base side (rotor head 4 side) of the wind turbine blade 5. Is the radial direction.

<First Embodiment>
A slewing ring bearing 10A of the embodiment shown in FIG. 1 is a rolling bearing that includes race rings 14 and 15 formed on an inner ring 11 and an outer ring 12A, and a rolling element 13 is sandwiched between the opposed race rings 14 and 15. is there. In the illustrated slewing ring bearing 10 </ b> A, two sets of the race rings 14 and 15 are formed vertically and the rolling elements 13 are arranged in two upper and lower stages, but there is no particular limitation.

In the slewing ring bearing 10A of the present embodiment, the rigidity reinforcing portion 20A in which the rigidity of the outer ring is increased from the surroundings is provided in the circumferential direction region where the bearing surface pressure is high. Note that the distribution of bearing surface pressure can be obtained by a prior calculation.
The illustrated rigidity-enhancing portion 20 is a wide portion that is widened outwardly with the outer diameter of the outer ring 12A being a non-perfect circle. That is, the rigidity-enhancing portion 20A of the outer ring 12A is a region where the outer ring width ta in the left-right direction (A-A cross section) is wider than the outer ring width tb in the vertical direction (ta> tb). In other words, in the plan view of the outer ring 12A, the outer ring width ta in the left-right direction where the bearing surface pressure is high is maximized, and gradually increases to the outer ring width tb in the vertical direction where the bearing surface pressure is low and the minimum width. The shape is changed.

  According to the structure of the slewing ring bearing 10A, since the rigidity reinforcing portion 20A in which the rigidity of the outer ring 12A is increased from the surroundings is provided in the region where the bearing surface pressure is high in the circumferential direction, the rigidity reinforcing portion 20A is provided. The rigidity of the outer ring changes in the circumferential direction so as to increase in a region where the bearing surface pressure is high. Such an improvement in the rigidity of the outer ring 12A improves the rigidity of the entire slewing ring bearing 10A in the same manner. Therefore, the increase in weight is minimized and the disturbance generated in the surface pressure distribution is eliminated, and the entire circumference is reduced. A substantially uniform surface pressure distribution can be realized.

That is, the rigidity-enhancing portion 20A of the outer ring 12A is set with a partly high rigidity with respect to the circumferential region where the bearing surface pressure is high and easily deformed. The rigidity reinforcing portion 20A that causes an increase in weight is not provided. Therefore, the slewing ring bearing 10A of the present embodiment can suppress the overall weight of the slewing ring bearing 10A while maintaining the bearing performance by making the surface pressure distribution uniform.
In the illustrated swivel ring bearing 10A, the rigidity-enhancing portion 20A is formed with the outer ring width ta wide in the left-right direction, but the circumferential direction region of the rigidity-enhancing portion 20A is appropriately set according to the region of the bearing surface pressure. Needless to say, it can be changed.

A slewing ring bearing 10B shown in FIG. 2 shows a first modified example in which a rigidity enhancing portion 20B is provided on the inner ring 11A in place of the rigidity enhancing portion 20A of the outer ring 12A described above. In addition, the same code | symbol is attached | subjected to the part similar to embodiment mentioned above, and the detailed description is abbreviate | omitted.
The illustrated rigidity-enhanced portion 20B is a wide portion that is widened inward by making the inner diameter of the inner ring 11A a non-perfect circle. That is, the rigidity reinforcing portion 20B of the inner ring 11 is a region in which the inner ring width in the left-right direction (BB cross section) is wider than the inner ring width in the up-down direction. In other words, in the plan view of the inner ring 11A, the inner ring width in the left-right direction where the bearing surface pressure is high is maximized, and the outer ring width is gradually changed to the inner ring width in the vertical direction where the bearing surface pressure is low and the minimum width. The shape is

According to such a structure of the slewing ring bearing 10B, the rigidity reinforcing portion 20B in which the rigidity of the inner ring 11A is increased from the surroundings is provided in the region where the bearing surface pressure is high in the circumferential direction. The rigidity of the inner ring changes in the circumferential direction so as to increase in a region where the bearing surface pressure is high. Such an improvement in the rigidity of the inner ring 11A improves the rigidity of the entire slewing ring bearing 10B in the same manner as in the above-described embodiment, so that an increase in weight is suppressed to a necessary minimum and a surface pressure distribution is generated. Disturbances can be eliminated and a substantially uniform surface pressure distribution can be realized over the entire circumference.
In addition, the rigidity reinforcement | strengthening part 20B of the inner ring | wheel 11A mentioned above and the rigidity reinforcement | strengthening part 20A of the outer ring | wheel 12A not only employ | adopt each independently, but the structure which combined both is also possible.

Moreover, although both embodiment mentioned above and the 1st modification were set as rigid reinforcement | strengthening part 20A, 20B of a rectangular cross section, for example like the 2nd modification shown in FIG. 3, and the 3rd modification shown in FIG. It is good also as the rigidity reinforcement parts 20C and 20D which made the cross-sectional shape trapezoid shape.
In the second modification shown in FIG. 3, the axial cross-sectional shape of the slewing ring bearing 10C is such that the side on the upper surface side that receives the bearing surface pressure is long with respect to the rigidity-enhancing portion 20A of the outer ring 12A shown in FIG. A trapezoidal shape in which the sides on the parallel lower surface side are shortened is adopted. That is, the rigidity reinforcing portion 20C is an inclined surface in which the lower part of the outer peripheral surface forming the wide portion in the outer ring 12A ′ is narrowed in the inner peripheral direction.

On the other hand, in the third modification shown in FIG. 4, the axial cross-sectional shape of the slewing ring bearing 10 </ b> D has a long side on the upper surface side that receives the bearing surface pressure with respect to the rigidity reinforcing portion 20 </ b> B of the inner ring 11 </ b> A shown in FIG. A trapezoidal shape with a shorter side on the lower side parallel to the side is employed. In other words, the rigidity reinforcing portion 20D is an inclined surface in which the lower part of the inner peripheral surface forming the wide portion in the inner ring 11A ′ is narrowed in the outer peripheral direction.
As described above, the rigidity-enhanced portions 20C and 20D in which the wide portion has a trapezoidal cross-sectional shape have a long upper surface side receiving the bearing surface pressure and a lower surface side parallel to the upper surface side. Since it is a shape, it is possible to efficiently increase the cross-sectional area and rigidity while minimizing the increase in weight, and to eliminate the disturbance that occurs in the surface pressure distribution.

Moreover, it is good also as a structure which replaces with 10 A of turning ring bearings of this embodiment mentioned above, ie, replaces the rigidity reinforcement part 20 which forms a wide part, and attaches a reinforcement member.
A slewing ring bearing 10E of the fourth modification shown in FIG. 5 is a rigid reinforcing portion 20E in which a rib 30 of a reinforcing member is attached to the outer peripheral surface of the outer ring 12. A plurality of ribs 30 are attached to the outer ring 12 in a region where the bearing surface pressure is high in the circumferential direction by welding or the like. The region of the outer peripheral surface to which such a rib 30 is attached is substantially the same as the wide portion of the rigidity reinforcing portion 20A described above. In this case, the pitches in the circumferential direction for attaching the ribs 30 may be equal pitches, or may be denser as the bearing surface pressure is higher.

A slewing ring bearing 10F of the fifth modification shown in FIG. 6 is a rigid reinforcing portion 20F in which a reinforcing plate 31 of a reinforcing member is attached to the outer peripheral surface of the outer ring 12. The reinforcing plate 31 is attached to the outer ring 12 in a region where the bearing surface pressure is high in the circumferential direction by welding or the like. The region of the outer peripheral surface to which such a reinforcing plate 31 is attached is substantially the same as the wide portion of the rigidity reinforcing portion 20A described above.
In this case, the plate thickness of the reinforcing plate 31 may be the same as shown in FIGS. 6A and 6B, for example, but the bearing surface pressure is high as shown in 6C for example. You may attach the reinforcement board 31A thickened as the area | region.

Further, the above-described reinforcing member may be partially attached to the upper surface side in the vertical direction so as to increase the rigidity of the upper surface side that receives the bearing surface pressure, for example, as in the sixth modification shown in FIG. Good. That is, in the illustrated sixth modified example, the rigid reinforcing portion 20G is provided with the reinforcing plate 31B attached only to the upper half of the outer peripheral surface of the outer ring 12. The rigid reinforcing portion 20G to which such a reinforcing plate 31B is attached has the same effect as the rigid reinforcing portion 20C of the second modified example (see FIG. 3) in which the cross-sectional shape of the wide portion formed on the outer ring 12A ′ is trapezoidal. Can be obtained.
In this case, the reinforcing plate 31B may have the same plate thickness, or may have a plate thickness that is increased in a region where the bearing surface pressure is higher. Instead of the reinforcing plate 31B, ribs as shown in the fourth modification (see FIG. 5) may be employed.

Further, in the fourth to sixth modifications described above, the rib 30 of the reinforcing member and the reinforcing plates 31, 31 </ b> A, 31 </ b> B are attached to the outer peripheral surface of the outer ring 12. It can also be attached to the peripheral surface.
The formation of the rigidity-enhanced portions 20E, 20F, and 20G by such a reinforcing member can change the rigidity of the inner ring 11 and the outer ring 12 in the circumferential direction according to the bearing surface pressure, and therefore, the increase in weight is minimized. The disturbance generated in the surface pressure distribution can be eliminated.

<Second Embodiment>
Next, a second embodiment of the slewing ring bearing structure according to the present invention will be described with reference to FIGS. 8 to 9 are drawings exaggerating the curvature and the like of the main part. The same reference numerals are given to the same parts as those in the above-described embodiment, and the detailed description thereof will be omitted.
FIG. 8 shows a standard state where the contact angle θ is in a normal state with respect to the spherical rolling element 13 sandwiched between the race ring 14 of the inner ring 11 and the race ring 15 of the outer ring 12. In such a standard state, the initial contact angle and the contact angle θ which are 45 degrees from the horizontal axis and the vertical axis respectively coincide with each other, and a total of four contact positions T are formed. In addition, the radius of the rolling element 13 is r, and the curved surfaces of the races 14 and 15 are arcs of radius R.

In the standard state shown in FIG. 8, as shown in FIG. 9A, the ball load F acts in the direction of the contact angle θ that coincides with the initial contact angle of 45 degrees, and the contact angle θ is the center. A symmetrical contact ellipse and surface pressure distribution are formed.
A normal rolling bearing is manufactured so that the initial contact angle indicated by a broken line of 45 degrees is constant in the circumferential direction as “normal” shown on the left side of FIG. Then, the contact angle θ during operation changes, for example, like a sine curve indicated by a solid line in FIG. 11 depending on the load condition and the amount of structural deformation. For this reason, as shown in FIG. 9B, when the contact angle θ is greatly changed to θ1, the contact ellipse is placed on the edge portion, so that the surface pressure is rapidly increased by the edge placement. In addition, the edge part in this case becomes the edge part 15a of the bearing ring 15. FIG.

Therefore, in this embodiment, in the rolling bearing in which the rolling elements 13 are sandwiched between the bearing rings 14 and 15 formed on the inner ring 11 and the outer ring 12, the rolling elements 13 are in contact with the surfaces of the bearing rings 14 and 15 when there is no load. The initial contact angle is set by changing it in the circumferential direction so as to reduce the maximum surface pressure during load application and structural deformation. That is, as shown in “change the initial contact angle” in FIGS. 10 and 11, the initial contact angle indicated by the broken line is shifted in phase from the contact angle during operation indicated by the solid line, and the sine curve is reversed in the upper and lower peaks. It is changed in the circumferential direction.
In this case, as shown in FIG. 10, the peak of the initial contact angle indicated by the broken line is such that the lower peak θa is smaller than the standard initial contact angle of 45 degrees and the upper field peak θb is larger than the standard initial contact angle of 45 degrees. Yes.

  According to such a slewing ring bearing structure, the setting of the initial contact angle at which the rolling elements 13 contact the surfaces of the race rings 14 and 15 at no load reduces the load so that the maximum surface pressure at the time of structural deformation is reduced. Since the contact angle θ does not change greatly during load loading and structural deformation, it prevents the contact pressure from rising rapidly due to the contact ellipse resting on the edge part. it can. That is, since the initial setting angle is set small in advance in the circumferential direction angle where the driving contact angle is large, on the contrary, the initial setting angle is set large in advance in the circumferential direction angle where the driving contact angle is small. The contact angle θ that changes when a load is applied can be prevented from changing to a value far from the normal initial contact angle of 45 degrees.

  If the change in the contact angle θ during load loading and structural deformation is suppressed in this way, it is possible to prevent the contact ellipse from being placed on the edge portion due to the change in the contact angle θ and the surface pressure from rapidly increasing. In other words, the initial contact angle, which was constant in the circumferential direction, is provided to change in the circumferential direction so as to reduce the maximum surface pressure when the load is applied and the structure is deformed. The ellipse does not ride on the edge portion, and therefore it is possible to prevent a sudden increase in surface pressure by suppressing a change in the contact angle θ. Specifically, as shown in FIG. 11, the change in the driving contact angle is reduced, in other words, the driving contact angle approaches the normal initial contact angle of 45 degrees. The maximum value of pressure is reduced by ΔP.

<Third Embodiment>
Finally, a third embodiment of the slewing ring bearing structure according to the present invention will be described with reference to FIGS. 8, 12, and 13. Note that FIG. 12 is an exaggerated view of the curvature and the like of essential parts, and the same reference numerals are given to the same parts as those in the above-described embodiment, and the detailed description thereof is omitted.
The bearing inner pressure of the sliding bearing depends on the diameter of the rolling element 13 and the groove radius of the races 14 and 15, that is, the ratio of the radius r of the rolling element 13 and the groove radius R of the arc forming the races 14 and 15 ( It varies depending on the groove curvature = R / 2r). More specifically, the groove curvature becomes a value close to 50%, and the surface pressure decreases as the diameter 2r of the rolling element 13 and the groove radius R of the races 14 and 15 are closer.
However, when the diameter of the rolling element 13 and the groove radius R become close to each other, the contact area of the rolling element 13 increases, so that the bearing torque (force required for bearing rotation) of the sliding bearing increases and the power loss due to heat generation increases. Increase.

  Therefore, in the slewing ring bearing structure of the present embodiment, in the rolling bearing in which the rolling elements 13 are sandwiched between the bearing rings 14 and 15 formed on the inner ring 12 and the outer ring 13, for example, as shown in FIG. , 15 is set by changing it in the circumferential direction so as to reduce the maximum surface pressure during load application and structural deformation. That is, the groove radius R, which is normally constant in the circumferential direction, is manufactured by changing in advance in the circumferential direction so as to reduce the maximum surface pressure in this embodiment.

  In the specific example shown in FIG. 12, the groove radius R of the bearing ring 15 is smaller than the groove radius R ′ of the bearing ring 14 (R <R ′). The moving body 13 is not in contact. However, when the rolling element 13 is in contact, the inner ring 11 is moved or deformed by a load during operation, so that the rolling element 13 is also in contact with the race ring 14 on the inner ring 11 side. As a result, as shown in FIG. 13, the constant groove curvature at the “normal” time is “change the groove curvature in the circumferential direction when the bearing is manufactured”, thereby reducing the maximum value of the surface pressure by ΔP.

  According to the slewing ring bearing structure of this embodiment, since the groove radii of the race rings 14 and 15 are set in the circumferential direction so as to reduce the load load and the maximum surface pressure during structural deformation, It is possible to suppress the surface pressure at the portion where the maximum surface pressure is generated and to suppress the increase in bearing torque to a minimum. In other words, the groove radius R of the races 14 and 15 that is constant in the circumferential direction changes in the circumferential direction so as to reduce the load surface and the maximum surface pressure at the time of structural deformation. In this case, the groove curvature, which is the relationship (ratio) between the diameter of the rolling element 13 and the groove radius of the races 14 and 15, is optimized, and the maximum surface pressure and bearing torque can be suppressed.

As described above, according to the slewing ring bearing structure of each of the embodiments described above, the disturbance in the surface pressure distribution due to the structural deformation is caused by the bearing performance due to the rigidity adjustment and change that minimizes the increase in the weight of the rolling bearing. It is possible to maintain a good bearing performance by preventing adverse effects on the bearing.
Further, by optimizing the initial contact angle and the groove radius of the bearing ring by appropriately changing them in the circumferential direction, it becomes possible to prevent the surface pressure from rapidly increasing or to suppress the maximum surface pressure and the bearing torque.
As a result, the maximum value of the surface pressure can be suppressed, and the use limit can be raised for rolling bearings having the same dimensions.

And if the rolling bearing mentioned above is employ | adopted as a turning wheel bearing of the yaw drive device of the wind power generator 1, or a pitch drive device, the upper structure of the tower 2 can be reduced in weight and a load burden can be reduced.
In addition, this invention is not limited to embodiment mentioned above, In the range which does not deviate from the summary, it can change suitably.

DESCRIPTION OF SYMBOLS 1 Wind power generator 2 Tower 3 Nacelle 4 Rotor head 5 Windmill blade 10, 10A-10G Slewing ring bearing (rolling bearing)
11, 11A ′ Inner ring 12, 12A ′ Outer ring 13 Rolling element 14, 15 Track ring 20A-20G Rigidity strengthening portion 30 Rib (reinforcing member)
31, 31A, 31B Reinforcing plate

Claims (6)

A rolling ring slewing ring bearing structure in which a rolling element is sandwiched between race rings formed on an inner ring and an outer ring,
A slewing ring bearing structure characterized in that a rigidity-enhancing portion in which the rigidity of the inner ring and / or the outer ring is increased from the periphery is provided in a circumferential region where the bearing surface pressure is high.   2. The slewing ring bearing structure according to claim 1, wherein the rigidity reinforcing portion is a wide portion in which an inner diameter of the inner ring and / or an outer diameter of the outer ring is a non-circular shape.   The slewing ring bearing structure according to claim 2, wherein the wide portion has a trapezoidal axial cross-sectional shape.   The slewing wheel bearing structure according to claim 1, wherein the rigidity reinforcing portion includes a reinforcing member attached to an outer peripheral surface of the outer ring and / or an inner peripheral surface of the inner ring. A rolling ring slewing ring bearing structure in which a rolling element is sandwiched between race rings formed on an inner ring and an outer ring,
A slewing ring bearing characterized in that an initial contact angle at which the rolling element contacts the surface of the raceway when no load is applied is set by changing in a circumferential direction so as to reduce the maximum surface pressure during load application and structural deformation. Construction. A rolling ring slewing ring bearing structure in which a rolling element is sandwiched between race rings formed on an inner ring and an outer ring,
A slewing ring bearing structure characterized in that a groove radius of the bearing ring is set to be changed in a circumferential direction so as to reduce a load load and a maximum surface pressure at the time of structural deformation.

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