JP2017057951A - Double row self-aligning roller bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double row self-aligning roller bearing that is suitable to be used in a case where different loads act on right and left roller rows, and can secure a large load capacity and prolong its service life without strength poverty of a holder.SOLUTION: A double row self-aligning roller bearing 1 is provided with right and left rows of rollers 4, 5 between an inner ring 2 and an outer ring 3. A raceway surface 3a of the outer ring 3 is formed into a spherical shape, and outer peripheral surfaces of the rollers 4, 5 have a cross sectional form along the raceway 3a of the outer ring 3. For the rollers 4, 5, a length L1 of the left roller 4 and a length L2 of the right roller 5 are different from each other. A holder 10 includes an annulus part 11 arranged between the left roller 4 and the right roller 5, and a plurality of column parts 12a, 12b respectively extending from the annulus part 11 toward right and left sides in a width direction. The holder is an integrated holder in which the left roller 4 is held between the columns part 12a extending leftward and the right roller 5 is held between the column parts 12b extending rightward.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a double-row self-aligning roller bearing applied to an application in which uneven loads are applied to the left and right two-row rollers, for example, a bearing that supports a main shaft of a wind power generator or an industrial machine.

  In addition to the radial load caused by the weight of the blade and the rotor head, an axial load caused by wind force acts on the bearing that supports the main shaft of the wind power generator. When the bearing is a double-row self-aligning roller bearing, only one of the two rows of left and right rollers mainly receives an axial load. That is, one row of rollers receives both a radial load and an axial load, while the other row of rollers receives only a radial load. Since the axial load in one direction is larger than the radial load, the roller in the row subjected to the axial load is more likely to cause surface damage and wear and has a shorter rolling life than the roller in the row not subjected to the axial load. The actual life of the entire bearing is determined by the rolling life of the rollers in the row subjected to this axial load.

  To simply improve the life of the bearing, it is only necessary to increase the load capacity of the entire bearing using a large-sized bearing, but in that case, only the roller in a row that receives almost no axial load has the load capacity and rolling life. There is a lot of design waste.

  Therefore, for example, as shown in FIG. 5, the lengths L1 and L2 of the left and right rows of rollers 4 and 5 interposed between the inner ring 2 and the outer ring 3 are made different from each other, whereby the row of rollers 5 receiving the axial load. It has been proposed to make the load capacity of the roller 4 larger than the load capacity of the rollers 4 in a row that hardly receives an axial load (Patent Document 1). By appropriately setting the load capacities of the rollers 4 and 5 in each of the left and right rows, the rolling lives of the rollers 4 and 5 in the left and right rows become substantially the same, and the substantial life of the entire bearing can be improved.

International Publication No. 2005/050038 Pamphlet

  The double-row self-aligning roller bearing 1 described in Patent Document 1 shown in FIG. 5 is provided with an intermediate collar 8 for guiding the left and right rows of rollers 4 and 5 in the middle of the outer peripheral surface of the inner ring 2. The middle collar 8 needs to have a certain thickness in the width direction in order to ensure strength that can withstand the induced thrust load of the rollers 4 and 5. Therefore, within the limited width dimension of the bearing, the lengths L1 and L2 of the rollers 4 and 5 cannot be made too long, and there is a problem that the load capacity of the entire bearing cannot be increased as expected.

  The middle collar 8 is provided to receive the induced thrust load of the rollers 4 and 5 when the rollers 4 and 5 in the left and right rows are asymmetrical rollers. It was noted that the middle brim 8 could be eliminated if no load was generated. Without the intermediate collar 8, the lengths L1 and L2 of the rollers 4 and 5 can be increased to increase the load capacity of the entire bearing. As shown in an exaggerated manner in FIG. 6, the “asymmetric roller” is a roller in which the position of the maximum diameter deviates from the center of the roller length, and the “symmetric roller” is a roller in which the position of the maximum diameter is a roller. It is a roller located in the center of the length.

  However, when the lengths L1 and L2 of the rollers 4 and 5 are lengthened, the left and right rollers 4 and 5 approach each other, so that each of the annular portions 11 of the cages 10L and 10R (FIG. 5) that hold the rollers 4 and 5 holds. The thickness in the width direction must be reduced. When using the comb-shaped cages 10L and 10R in which the column part 12 extends in one direction from the annular part 11, if the thickness in the width direction of the annular part 11 is thin, the cages 10L and 10R have insufficient strength, There is a possibility that the rollers 4 and 5 cannot be stably held.

  The object of the present invention is suitable for use in applications in which loads of different magnitudes act on the left and right roller rows, ensuring a large load capacity and extending the life without causing a lack of strength of the cage. It is to provide a double-row self-aligning roller bearing capable.

  In the double-row self-aligning roller bearing according to the present invention, rollers are interposed in two right and left rows between the inner ring and the outer ring, the raceway surface of the outer ring is spherical, and the left and right two-row rollers are arranged in the left row. The rollers and the right row rollers have different lengths, and have a cage that holds both the left row roller and the right row roller, and the cage includes the left row roller and the right row roller. An annular portion disposed between the rollers, and a plurality of column portions extending from the annular portion to the left and right sides in the width direction, and the left row of rollers is held between the column portions extending to the left side, It is an integrated type retainer in which the right row rollers are held between pillars extending to the right.

  According to this configuration, by making the lengths of the left row roller and the right row roller different from each other, the longer roller has a larger load capacity than the shorter roller. When using double row self-aligning roller bearings in applications where different loads are applied to the left and right rows, the roller in the row that receives a large load compared to the left and right rows of rollers is a long roller. In addition, the rollers in a row that receive a small load in comparison are rollers having a short length. Thereby, a load can be shared by the ratio according to the load capacity which the roller of each right and left row has. As a result, the surface pressures of the rollers in the left and right rows are equalized. As a result, a large load capacity can be ensured in the entire bearing, and the substantial life of the entire bearing can be improved.

  In order to increase the load capacity of the entire bearing, if the length of the left and right rollers is increased without changing the width of the inner and outer rings, the left and right rollers approach each other. An annular portion of the cage is disposed between the close left and right rollers. Since the cage is an integrated type that holds the left and right rows of rollers, and the annular part is shared by both the left and right rows, even if the left and right rollers are close, Compared to the configuration in which the annular portions of the cage for the right row are arranged between the left and right rollers, a sufficient thickness in the width direction of the annular portion can be secured. For this reason, insufficient strength of the cage is avoided, and the rollers can be stably held by the cage. As described above, by sharing the load at a ratio according to the load capacity of each of the left and right rows of rollers, the surface pressure of the left and right rows of rollers becomes equal, so the integrated retainer Even if the rollers are held, the rollers can be driven smoothly by the cage.

In this invention, the left and right two rows of rollers are symmetrical rollers having a maximum diameter located at the center of the roller length, and a portion between the left row rollers and the right row rollers on the outer peripheral surface of the inner ring. A configuration in which there is no middle brim may be used.
By making the left and right rollers symmetrical, the generation of induced thrust load on the rollers is eliminated, and the middle collar can be eliminated. When the middle collar is not present, the length of the roller can be increased as compared with the case where the middle collar is present, and the load capacity of the entire bearing can be improved.

In the present invention, a guide wheel that freely rotates with respect to the inner ring and the cage and guides the left and right rows of rollers may be provided between the inner ring and the cage.
By providing the guide ring, the skew of the rollers can be suppressed even if there is no middle collar. Symmetrical rollers have a longer roller length than asymmetrical rollers. Therefore, if an intermediate collar is provided, the thickness in the width direction is reduced, and damage is likely to occur during production.

This double row self-aligning roller bearing is suitable for supporting the main shaft of the wind power generator.
Double row spherical roller bearings that support the main shaft of a wind turbine generator are subject to radial loads due to the weight of the blades and rotor head, and axial loads due to wind force, and loads of different magnitudes on the left and right rows. . That is, one row receives both radial and axial loads, while the other row receives almost only radial loads. In that case, the roller in the row that receives the axial load is a long roller, and the roller in the row that receives only the radial load is a short roller. Can be even.

  In the double-row self-aligning roller bearing according to the present invention, rollers are interposed in two right and left rows between the inner ring and the outer ring, the raceway surface of the outer ring is spherical, and the outer circumferential surface of the left and right two-row rollers is the outer surface. The cross-sectional shape along the raceway surface of the outer ring, wherein the left and right rows of rollers have different lengths of the left row and right row rollers, and both the left row roller and the right row roller The retainer includes an annular portion disposed between the left row roller and the right row roller, and a plurality of each extending from the annular portion to the left and right sides in the width direction. The left row rollers are held between the column portions extending to the left side, and the right row rollers are held between the column portions extending to the right side. Suitable for applications where loads of different magnitudes are applied to the roller train, large without causing insufficient cage strength. Can be ensured and the life of the Do load capacity.

It is sectional drawing of the double row self-aligning roller bearing concerning one Embodiment of this invention. It is an expanded sectional view of the cage of the double row self-aligning roller bearing. It is the perspective view which notched and represented a part of example of the spindle support apparatus of the wind power generator. It is a fracture side view of the spindle support device. It is sectional drawing of the double row self-aligning roller bearing of a proposal example. It is explanatory drawing of an asymmetrical roller.

An embodiment of the present invention will be described with reference to FIG.
In this double-row self-aligning roller bearing 1, rollers 4 and 5 are interposed in two right and left rows arranged in the width direction between an inner ring 2 and an outer ring 3. The raceway surface 3 a of the outer ring 3 has a spherical shape, and the rollers 4 and 5 in each of the left and right rows have a cross-sectional shape along the raceway surface 3 a of the outer ring 3. In other words, the outer peripheral surfaces of the rollers 4 and 5 are rotating curved surfaces obtained by rotating an arc along the raceway surface 3a of the outer ring 3 around the center lines C1 and C2. The inner ring 2 is formed with double-row raceway surfaces 2a and 2b having a cross-sectional shape along the outer peripheral surfaces of the rollers 4 and 5 in the left and right rows. At both ends of the outer peripheral surface of the inner ring 2, collars 6 and 7 are provided, respectively. There is no middle collar at the center of the outer peripheral surface of the inner ring 2, that is, the portion between the left row roller 4 and the right row roller 5.

The rollers 4 and 5 in each of the left and right rows are symmetrical rollers in which the positions of the maximum diameters D1 _max and D2 _max are located at the center A1 and A2 of the roller length. The rollers 4 and 5 made of symmetrical rollers do not generate an induced thrust load. For this reason, it is not necessary to support the rollers 4 and 5 with the middle collar, and the middle collar can be eliminated.

The left row roller 4 and the right row roller 5 have different lengths L1 and L2 along the center lines C1 and C2 and different contact angles θ1 and θ2. In this case, the contact angle θ2 of the long roller 5 with the length L2 is set larger than the contact angle θ1 of the short roller 4 with the length L1. In this embodiment, the maximum diameters D1 _max and D2 _max of the left and right rollers 4 and 5 are the same.

  The rollers 4 and 5 in each of the left and right rows are held by a cage 10. As shown in the developed cross-sectional view of FIG. 2, the cage 10 has a comb shape in which a plurality of column portions 12a and 12b extend on both the left and right sides from an annular portion 11 positioned between the rollers 4 and 5 in the left and right rows. Thus, the left row rollers 4 are held in the pockets between the left column portions 12a, and the right row rollers 5 are held in the pockets between the right column portions 12b. That is, the cage 10 is an integrated cage that holds the rollers 4 and 5 in the left and right rows. Compared to the configuration in which the annular portions of the left row retainer and the right row retainer are arranged between the left and right rollers 4 and 5, the integrated retainer 10 has a width of the annular portion 11. There is an advantage that the strength is high because the thickness in the direction can be widened.

  Further, a guide wheel 13 is provided between the inner ring 2 and the cage 10 between the left and right roller rows so as to contact the end surfaces of the rollers 4 and 5 in the left and right rows and guide these rollers 4 and 5. . The guide wheel 13 is provided so as to freely rotate with respect to any of the rollers 4 and 5, the inner ring 2, and the cage 10. By providing such a guide wheel 13, the skew of the rollers 4 and 5 can be suppressed even if there is no middle collar at the center of the outer peripheral surface of the inner ring 2.

  The double-row self-aligning roller bearing 1 having this configuration is used in applications in which loads of different sizes act on the left and right roller rows, for example, one roller row receives an axial load and a radial load, and the other roller row receives Is used for applications that receive almost only radial loads. Specifically, it is used for a spindle support bearing of a wind power generator.

  When used in the above-mentioned application, the roller in the row that receives the axial load is the roller 5 in the right row having a long length L2, and the roller in the row that receives almost no axial load is the roller 4 in the left row that has a short length L1. To do. Further, the contact angle θ2 of the right row roller 5 that receives the axial load is made larger than the contact angle θ1 of the left row roller 4 that hardly receives the axial load. Accordingly, the long roller 5 having a large load capacity and the length L1 receives both the axial load and the radial load, and the short roller 4 having a small load capacity and the length L1 receives almost only the radial load.

  By appropriately setting the lengths L1 and L2 of the rollers 4 and 5, it is possible to share the load at a ratio according to the load capacity of the rollers 4 and 5 in the left and right rows. As a result, the surface pressures of the rollers 4 and 5 in the left and right rows are equalized. As a result, a large load capacity can be ensured in the entire bearing, and the substantial life of the entire bearing can be improved.

  Further, the double-row self-aligning roller bearing 1 shown in FIG. 1 has the rollers 4 and 5 made symmetrical rollers and the middle collar is eliminated, so that the length of the rollers 4 and 5 is increased and the load capacity of the entire bearing is increased. It is possible to further increase. The rollers 4 and 5 may be asymmetric rollers. In that case, an induced thrust load of the rollers 4 and 5 is generated, so that it is necessary to provide a middle collar on the inner ring 2.

  When the lengths L1 and L2 of the left and right rollers 4 and 5 are increased in order to increase the load capacity of the entire bearing as in the double-row self-aligning roller bearing 1 of FIG. The distance between the left and right rollers 4 and 5 on which 11 is disposed is reduced. However, by making the retainer 10 an integral type that retains the left row roller 4 and the right row roller 5, the thickness of the annular portion 11 in the width direction can be sufficiently secured. Insufficient strength can be avoided. For this reason, the rollers 4 and 5 can be stably held by the cage 10. As described above, the load is shared at a ratio corresponding to the load capacity of the rollers 4 and 5 in the left and right rows, so that the surface pressure of the rollers 4 and 5 in the left and right rows is equalized. Even if the rollers 10 hold the left and right rollers 4 and 5 in the container 10, the rollers 4 and 5 can be smoothly driven by the holder 10.

  3 and 4 show an example of the spindle support device of the wind turbine generator. A casing 23a of the nacelle 23 is installed on the support base 21 via a swivel bearing 22 (FIG. 4) so as to be horizontally swivelable. In the casing 23 a of the nacelle 23, a main shaft 26 is rotatably installed via a main shaft support bearing 25 installed in the bearing housing 24, and a blade 27 serving as a swirl wing is formed on a portion protruding from the casing 23 a of the main shaft 26. Is attached. The other end of the main shaft 26 is connected to the speed increaser 28, and the output shaft of the speed increaser 28 is coupled to the rotor shaft of the generator 29. The nacelle 23 is turned at an arbitrary angle by the turning motor 30 via the speed reducer 31.

  In the illustrated example, two main shaft support bearings 25 are arranged side by side, but may be one. As the main shaft support bearing 25, the double-row self-aligning roller bearing 1 according to any one of the above embodiments is used. In this case, since both the radial load and the axial load are applied to the row far from the blade 27, the roller 5 having a large contact angle θ2 and a long length L2 is used as the roller in the row far from the blade 27. Since only the radial load is mainly applied to the row closer to the blade 27, the roller 4 having a small contact angle θ1 and a short length L1 is used as the roller closer to the blade 27.

  As mentioned above, although the form for implementing this invention based on the Example was demonstrated, embodiment disclosed here is an illustration and restrictive at no points. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 ... Double row self-aligning roller bearing 2 ... Inner ring 3 ... Outer ring 3a ... Raceway surface 4, 5 ... Roller 10 ... Cage 11 ... Ring part 12a, 12b ... Column part 13 ... Guide wheel 26 ... Main shaft A1, A2 ... Center of roller length D1 _max , D2 _max ... Maximum diameter L1, L2 ... Roller length

Claims (4)

Two rows of rollers are interposed between the inner ring and the outer ring, the outer ring raceway surface is spherical, and the left and right two rows of rollers have an outer circumferential surface having a cross-sectional shape along the outer raceway surface. Self-aligning roller bearing,
The left and right two rows of rollers have a cage in which the lengths of the left and right rows of rollers are different from each other and hold both the left and right rows of rollers. Has a ring portion disposed between the left row roller and the right row roller, and a plurality of column portions extending from the ring portion to the left and right sides in the width direction, and extending to the left side. A double-row self-aligning roller bearing, characterized in that the roller in the left row is held in between, and the roller in the right row is held between pillars extending to the right.   2. The double-row self-aligning roller bearing according to claim 1, wherein the left and right two-row rollers are symmetrical rollers in which a position of a maximum diameter is located at a center of a roller length, and the left row on the outer peripheral surface of the inner ring. A double-row self-aligning roller bearing in which a middle collar does not exist in a portion between the roller and the right-side roller.   The double-row self-aligning roller bearing according to claim 2, wherein a guide wheel is provided between the inner ring and the retainer so as to freely rotate with respect to the inner ring and the retainer and guide the left and right two rows of rollers. Has double row spherical roller bearings.   The double row spherical roller bearing according to any one of claims 1 to 3, wherein the double row spherical roller bearing is used for supporting a main shaft of a wind turbine generator.

Images