WO2012128103A1

WO2012128103A1 - Seal structure for slewing bearing, and slewing bearing

Info

Publication number: WO2012128103A1
Application number: PCT/JP2012/056278
Authority: WO
Inventors: 堀径生
Original assignee: Ntn株式会社
Priority date: 2011-03-18
Filing date: 2012-03-12
Publication date: 2012-09-27

Abstract

In a seal structure for a slewing bearing, a seal member (5) has a base part (6) and lip parts (9), with one of the lip parts (9) including a main rib (7) that extends at a slant. An annular protruding part (16) that protrudes radially is provided closer to the end part than a seal sliding contact surface part (2c) at the peripheral surface of a recess-side bearing ring (2), and a seal-sliding-side slanted part (16a) that slants toward the protruding tip so as to be positioned to the outside in the axial direction is provided at the inside surface of the annular protruding part (16) in the radial direction. In a protrusion-side bearing ring (1), a seal-anchoring-side slanted part (13a) that slants toward a groove bottom-side portion so as to be positioned to the outside in the axial direction is provided at the inner surface of an anchoring groove (13) at the groove-side surface of the peripheral surface of the base part (6).

Description

Slewing bearing seal structure and slewing bearing

Related applications

This application claims the priority of Japanese Patent Application No. 2011-060266 filed on March 18, 2011 and Japanese Patent Application No. 2012-008553 filed on January 19, 2012, which is incorporated herein by reference in its entirety. Quote as part.

The present invention is, for example, a swivel used for a swivel part of various machines used in the vicinity of the outdoors or indoors, such as a swivel seat for a yaw and a blade of a wind power generator, a deck crane, a construction machine, and a lifting machine. The present invention relates to a seal structure of a bearing and a slewing bearing.

Slewing bearings used for wind power generation devices such as yaw and swivel seats for blades are generally lubricated with grease. This slewing bearing is provided with a rubber seal in order to prevent foreign matters from entering from outside or grease leakage from inside the bearing (Patent Documents 1 and 2). Nitrile, chloroprene, acrylic, etc. are used as the material of this rubber.

Japanese Patent Laid-Open No. 7-310645 German utility model No. 20203372 specification

Especially, rubber seals used for slewing bearings for yaw and blades of wind power generators have an important function of preventing grease leakage from the viewpoint of protecting the surrounding environment. Since the slewing bearing is generally operated at a low speed, there is little problem of heat generation. However, as shown in FIG. 14, when additional grease is supplied from the greasing pipe 50, the pressure inside the bearing having the shaft center C is increased. Rises. As shown in the figure, the grease supply pipe 50 is a pipe that penetrates radially from the outer ring outer diameter surface 51 or the inner ring inner diameter surface 52 toward the bearing interior. As described above, since the pressure inside the bearing rises, the internal pressure acts on the rubber seal portion 53.

When the internal pressure generated in the rubber seal portion 53 is large, the seal lip 55 may be reversed or fall off from the seal fixing portion. The direction of the seal lip 55 is two patterns: an inward lip 55a extending inwardly in the axial direction of the bearing space as it goes toward the tip, and an outward lip 55b extending inclining outward in the axial direction of the bearing space as it goes toward the tip. is there.

In order to withstand the internal pressure, an inward lip 55a is required. However, if the inward lip 55a is applied with pressure higher than expected, there is a problem that the lip is reversed. As a means for preventing the problem, it is conceivable to increase the lip rigidity by increasing the thickness of the lip. However, if the thickness of the lip is increased, the sealing torque increases, which may affect the specifications of the drive device, that is, it may be necessary to increase the capacity of the turning torque.

An object of the present invention is to provide a seal structure for a slewing bearing and a slewing bearing that can prevent the lip portion of the seal member from being reversed and the seal member from falling off when the internal pressure is increased, and can reduce the seal torque. .

In the seal structure of the slewing bearing according to the present invention, a raceway groove is formed in each of the race rings of the inner ring and the outer ring, a plurality of rolling elements are provided between the race grooves of the inner and outer rings, and at the axial ends of the inner and outer rings, A step that is uneven in the axial direction is provided between the inner and outer rings, and an elastic seal member that seals the axial end of the inner and outer rings having the step is provided. The seal member includes a base fixed to a portion protruding from the concave raceway of the convex raceway that is the convex side of the step, and one or more that are in contact with the concave raceway that is the concave side of the step. One of the lip portions, and includes a main lip extending obliquely so as to be positioned on the inner side in the axial direction of the bearing space toward the tip, and on the bearing space side of the concave bearing ring. Provided on the peripheral surface is a seal slidable contact surface portion that slidably contacts the main lip of the seal member, and an annular protruding portion that protrudes in the radial direction is provided on the end side of the peripheral surface of the concave raceway. Provided on the inner surface in the axial direction of the annular protrusion is a seal sliding side inclined portion that is inclined so as to be positioned on the outer side in the axial direction toward the protruding tip.

An annular groove is provided on the peripheral surface of the convex raceway, and a fixing groove is provided on an outer surface in the axial direction at the bottom of the annular groove, and the base portion of the seal member includes the peripheral surface of the convex raceway and the circumferential surface. There is a groove for fitting into which the annular wall portion that is a portion between the inner surface of the fixed groove is fitted, and the groove side surface on the bearing space side of the inner surface of the fixed groove moves away from the bearing space toward the groove bottom side portion. A seal fixing side inclined portion that is inclined so as to be positioned on the side is provided.

According to this configuration, when internal pressure is applied to the seal member, the main lip is pressed against the seal sliding side inclined portion of the annular projection of the concave raceway, and the base is inclined to the seal fixing side of the convex raceway. Pressed against the part. That is, the main lip and the base of the seal member are both supported by the race ring. At this time, since the main lip and the base portion come into contact with the respective inclined portions facing each other, the inversion of the lip portion can be suppressed, and the seal member can be prevented from falling off the raceway. Accordingly, in order to prevent the lip portion from being reversed, it is not necessary to increase the lip rigidity by increasing the thickness of the lip portion. Therefore, the thickness of the lip portion can be made thinner than that of the conventional one, and the sealing torque can be reduced.

In addition, by inserting a part of the base portion of the seal member into the fixed groove provided on the peripheral surface of the convex raceway ring, the annular wall portion between the peripheral surface of the convex raceway ring and the inner surface of the fixed groove is Since the fitting member is fitted in the fitting groove, the seal member can be easily fixed to the convex race. Therefore, the number of assembly steps can be reduced. In this case, an adhesive or the like for fixing the seal member is not necessary, and other components such as a lid for suppressing the seal are also unnecessary, so that the number of components can be reduced and the manufacturing cost can be reduced. The workability when exchanging worn seal members is also greatly improved over the prior art.

Of the base portion of the seal member, the inner surface of the base portion facing the bottom of the annular groove of the convex raceway ring may be connected by a single curved surface or a continuous curved surface having no inflection point. Of the base portion of the seal member, the inner surface of the base portion facing the bottom portion of the annular groove of the convex raceway ring may be connected to a plurality of surfaces having intersection angles of 90 degrees or more and 180 degrees or less. The “intersection angle” refers to an angle viewed from the inside of the seal member. In these cases, the rigidity of the base portion of the seal member can be increased and local deformation can be prevented.

The angle of the intersection line connecting the axial inner side surface of the main lip and the base inner side surface of the base may be 180 degrees or more and 270 degrees or less. The “angle” refers to an angle viewed from the inside of the seal member. In this case, the main lip can be positively elastically deformed by applying an internal pressure to a portion connecting the axial inner side surface of the main lip and the base inner side surface of the base portion. Thereby, even if it is a case where the hooking amount of a base is small with respect to an annular wall part, it can prevent that the sealing member is pulled out by the base side.

The seal slide is formed so that the surface of the annular protrusion extending from the seal sliding side inclined portion toward the convex raceway and the surface of the fixing groove extending from the seal fixing side inclined portion toward the concave raceway are crossed. A moving side inclined portion and a seal fixing side inclined portion may be provided. In this case, the surface where the seal sliding side inclined portion is extended to the convex bearing ring side and the surface where the seal fixing side inclined portion of the fixing groove is extended to the concave bearing ring side are brought close to one plane so that the sealing member When the internal pressure is applied, the main lip and the base of the seal member can be more reliably brought into contact with the surface.

The main lip may be thinner than the base. In this case, the seal torque of the lip portion can be reduced, and the main lip can be positively elastically deformed when an internal pressure is applied to the seal member. As a result, the main lip is surely pressed against the seal sliding side inclined portion of the annular projection of the concave raceway, so that the sealing member can be used even when the hooking amount of the base portion is small relative to the annular wall portion. Can be prevented from coming out on the base side.

The bottom surface of the fitting groove of the seal base or the side surface of the groove on the bearing space side may be brought into contact with the seal base. As a result, the coefficient of friction is increased, the fixation of the seal base can be stabilized, and the suppression of grease leakage from the fixed part can be enhanced. Further, since the tightness of the seal lip can be maintained, the sealing performance can be stabilized.

The sealing member may be made of nitrile or chloroprene. The seal member may include, as one of the lip portions, a sub lip branched from the base portion separately from the main lip and in contact with the end surface of the concave raceway. By this sub lip, the sealing performance of the sealing member is further maintained, and grease leakage from the bearing space can be prevented.

The initial tightening allowance of the main lip may be 2 mm or more and 6 mm or less. By setting such an initial tightening allowance, it is possible to reduce the seal torque and prevent grease leakage from the bearing space.

The slewing bearing of the present invention is one to which any of the above-mentioned seal structures is applied. A wind turbine blade may be supported so as to be rotatable about an axis substantially perpendicular to the main shaft axis with respect to the main shaft. The nacelle of the windmill may be supported so as to be rotatable with respect to the support base.

Any combination of at least two configurations disclosed in the claims and / or the specification and / or drawings is included in the present invention. In particular, any combination of two or more of each claim in the claims is included in the present invention.

The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are for illustration and description only and should not be used to define the scope of the present invention. The scope of the invention is defined by the appended claims. In the accompanying drawings, the same reference numerals in a plurality of drawings indicate the same or corresponding parts.
It is a longitudinal cross-sectional view of the slewing bearing which concerns on 1st Embodiment of this invention. (A) is a longitudinal sectional view partially showing the seal structure and the like of the slewing bearing, and (B) is a longitudinal sectional view of a single seal member of the seal structure. It is a longitudinal cross-sectional view which shows partially the seal structure etc. of the slewing bearing which concern on 2nd Embodiment of this invention. It is a longitudinal cross-sectional view which shows partially the seal structure of the turning bearing etc. which concern on 3rd Embodiment of this invention. It is a longitudinal cross-sectional view which shows partially the seal structure of the turning bearing etc. which concern on 4th Embodiment of this invention. It is a longitudinal cross-sectional view which shows partially the seal structure of the turning bearing etc. which concern on 5th Embodiment of this invention. It is the perspective view which notched and represented a part of example of the wind power generator. It is a fracture side view of the wind power generator. It is a longitudinal cross-sectional view of the slewing bearing which concerns on the application example 1 of this invention. It is a longitudinal cross-sectional view which shows partially the seal structure etc. of the slewing bearing. It is a longitudinal cross-sectional view which shows partially the seal structure etc. of the slewing bearing which concerns on the application example 2 of this invention. It is a longitudinal cross-sectional view which shows partially the seal structure etc. of the slewing bearing which concerns on the application example 3 of this invention. It is a longitudinal cross-sectional view which shows partially the seal structure etc. of the slewing bearing which concerns on the application example 4 of this invention. It is a longitudinal cross-sectional view of the slewing bearing of the conventional example and its main part.

A seal structure for a slewing bearing according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2A and 2B. The following description also includes a description of the design method of the seal structure. This slewing bearing is, for example, a bearing that supports the blade of a wind turbine for wind power generation so that it can pivot about an axis substantially perpendicular to the main shaft axis or a nacelle of the wind turbine relative to a support base. Used as a bearing to support.

As shown in FIG. 1, the slewing bearing is adjacent to the inner ring 1, the outer ring 2, and a plurality of balls 3 that are rotatably interposed between the

raceway grooves

1 a and 2 a of the inner and

outer rings

1 and 2. A spacer (not shown) interposed between the

balls

3 and 3 and a seal member 5 described later are provided. Each of the

raceway grooves

1a and 2a of the inner and

outer rings

1 and 2 is composed of two curved surfaces. The two curved surfaces constituting each

raceway groove

1a, 2a are Gothic arch-shaped arcs having a larger radius of curvature than the balls 3 as rolling elements and different curvature centers. Each ball 3 is in contact with the curved surfaces of the inner ring raceway groove 1a and the outer ring raceway groove 2a at a point of contact with each other at four points. This slewing bearing is configured as a four-point contact ball bearing. The spacer is made of, for example, a resin material, and the spacer has a concave shape in which the ball contact surfaces on both sides form a spherical surface that is deeply recessed toward the center.

The outer ring 2 is provided with a plurality of through holes 2b at regular intervals in the circumferential direction. These through holes 2b are used, for example, for connecting and fixing the outer ring 2 to a support base 22 (FIGS. 7 and 8) described later. The inner ring 1 is also provided with a plurality of through holes 1b at regular intervals in the circumferential direction, and these through holes 1b are used for connecting and fixing the inner ring 1 to, for example, a casing 24 (FIGS. 7 and 8) of a nacelle 23 described later. Used for. Each through-

hole

1b, 2b is formed in parallel with the bearing axial direction.

The seal structure will be described. As shown in FIG. 1, steps δ that are uneven in the axial direction between the inner and

outer rings

1 and 2 are provided at the axial ends of the inner and

outer rings

1 and 2, in this example, at both ends in the axial direction. The bearing space 4 of the inner and

outer rings

1 and 2 is filled with grease, and the

seal members

5 and 5 seal both axial ends of the inner and

outer rings

1 and 2 having the step δ. The seal member 5 at one end in the axial direction (upper part in FIG. 1) will be described. In the upper seal member 5 of FIG. 1, the convex raceway that is the convex side of the step δ is the inner ring 1, and the concave raceway that is the concave side of the step δ is the outer ring 2.

The seal member 5 is made of an elastic body such as nitrile or chloroprene, and has a base portion 6 and a lip portion 9 including a main lip 7 and a sub lip 8 as shown in FIG. The base portion 6 and the lip portion 9 are provided integrally. The base portion 6 includes a seal fixing portion 10 that is fixed to the inner ring 1 that is a convex raceway ring, and a seal body portion 11 that is connected to the seal fixing portion 10. A fitting groove 10 a is provided on the inner peripheral surface side of the seal fixing portion 10 of the base portion 6. The fitting groove 10a is formed so as to open annularly outward in the axial direction.

The seal fixing portion 10 of the base portion 6 is fixed to a portion of the inner ring 1 that protrudes in the axial direction from the outer ring 2. An annular groove 12 is provided on the outer peripheral surface of the inner ring 1, and a fixed groove 13 recessed in a V shape toward the axially outer side (side away from the bearing space 4) on the axially outer surface at the bottom of the annular groove 12. Is provided. An annular wall portion 14, which is a portion between the outer peripheral surface and the inner surface of the fixed groove 13, is fitted into the fitting groove 10 a of the base portion 6. Further, on the groove side surface on the bearing space side on the inner surface of the fixed groove 13, there is provided a seal fixed side inclined portion 13 a that is inclined so as to be positioned outward in the axial direction toward the groove bottom side portion. When the seal fixing portion 10 is fixed to the inner ring 1, the tip end portion 10 b that is a part of the seal fixing portion 10 is abutted and fixed to the seal fixing side inclined portion 13 a and is formed on the outer peripheral surface of the inner ring 1. An engaging portion 10c, which is another part of the seal fixing portion 10, is engaged and fixed to the stepped portion 1c. Further, when an internal pressure is applied to the seal member 5, the tip end portion 10b of the seal fixing portion 10 is pressed against the seal fixing side inclined portion 13a.

As shown in FIG. 2B, in the seal member alone before the seal fixing portion 10 is fixed to the inner ring 1, the largest radial clearance between the tip portion 10b of the seal fixing portion 10 and the engaging portion 10c. δa is formed to be narrower than when the seal fixing portion 10 is fixed to the inner ring 1 (FIG. 2A). 2A, when the annular wall portion 14 of the inner ring 1 is fitted into the fitting groove 10a, the tip portion 10b of the seal fixing portion 10 is elastically deformed radially inward (in other words, For example, the seal fixing part 10 is in contact with the seal fixing side inclined part 13a (separated from the engaging part 10c). At the same time, the engaging portion 10 c of the seal fixing portion 10 is engaged with the step portion 1 c of the inner ring 1.

The inner side surface 15 on the inner side in the axial direction at the bottom of the annular groove 12 is formed, for example, in parallel with the inclined surface of the seal fixing side inclined portion 13a, and the base portion 6 of the seal member 5 does not interfere with the inner side surface 15 and the groove bottom surface. It is provided as follows. Of the base 6 of the seal member 5, the base inner side surface 6 a facing the bottom of the annular groove 12 is formed as a shape connected with a single curved surface or a continuous curved surface having no inflection point, forming a curved surface inward in the radial direction. Yes.

As shown in FIG. 2 (A), the main lip 7 of the lip portion 9 extends in an inclined manner so as to be located on the inner side in the axial direction of the bearing space toward the tip. The main lip 7 extends obliquely inward in the axial direction from the outer surface of the seal body 11 facing the inner peripheral surface of the outer ring of the seal body 11. As shown in FIG. 2B, the thickness t1 of the main lip 7 is provided to be thinner than the maximum radial thickness t2 of the seal body 11 of the base 6. Of the seal body 11 of the base 6, the angle α1 of the line connecting the base inner surface 6a facing the bottom of the annular groove 12 and the axial inner surface 7a of the main lip 7 is 180 degrees or more and 270 degrees or less. . In this embodiment, since the base inner side surface 6a is connected by a single curved surface or a continuous curved surface having no inflection point, the tangent line La passing through the axial inner side surface of the main lip 7 of the base inner side surface 6a The angle α1 of the intersection line connecting the axially inner side surfaces of the main lip 7 is set as described above. The “angle” refers to an angle viewed from the inside of the seal member 5. In addition, the initial fastening allowance of the main lip 7 (the amount of change in the radial position of the tip of the main lip 7 before and after assembling into the bearing) is set to 2 mm or more and 6 mm or less.

As shown in FIG. 2 (A), a seal sliding contact surface portion 2c for slidingly contacting the main lip 7 is provided on the inner peripheral surface of the outer ring 2 on the bearing space side of the outer ring 2 that is a concave raceway. An annular projecting portion 16 projecting in the radial direction is provided on the inner peripheral surface of the outer ring on the end side of the seal sliding contact surface portion 2c. A seal sliding side inclined portion 16a that is inclined so as to be positioned on the outer side in the axial direction toward the protruding tip is provided on the inner surface in the axial direction facing the bearing space in the annular protruding portion 16. When an internal pressure is applied to the seal member 5, the main lip 7 is pressed against the seal sliding side inclined portion 16a. Further, the seal sliding side slope 16 so that the surface S2 extending the seal sliding side inclined portion 16a to the inner ring 1 side and the surface S1 extending the seal fixing side inclined portion 13a of the fixing groove 13 to the outer ring 2 side intersect. A portion 16a and a seal fixing side inclined portion 13a are provided.

The auxiliary lip 8 of the lip portion 9 branches from the seal body portion 11 of the base portion 6 separately from the main lip 7 and contacts the end surface 2d of the outer ring 2. That is, the sub lip 8 extends in an axially inclining manner from the lower end surface portion of the seal body portion 11 facing the end surface 2d of the outer ring 2, and makes axial contact with the end surface 2d of the outer ring 2. As shown in FIG. 2B, the thickness t3 of the sub lip 8 is provided thinner than the thickness t4 of the seal body 11 in the axial direction. The secondary lip 8 is also called a dust lip.

As shown in FIG. 1, at the other axial end of the inner and outer rings 1 and 2 (lower part in FIG. 1), the convex raceway ring that is the convex side of the step δ is the outer ring 2, and the concave side of the step δ The concave raceway ring is the inner ring 1. Since the seal structure provided at the other end in the axial direction is the same as the seal structure at one end in the axial direction, the same reference numerals as those assigned to the seal structure are attached and the description thereof is omitted.

According to the seal structure of the slewing bearing described above, when the internal pressure is applied to the seal member 5, the main lip 7 is pressed against the seal sliding side inclined portion 16a of the annular protrusion 16 of the concave raceway, and the base portion 6 is pressed against the seal fixing side inclined portion 13a of the convex raceway. That is, the main lip 7 and the base 6 of the seal member 5 are both supported by the raceway ring. At this time, the main lip 7 and the base portion 6 come into contact with the respective

inclined portions

16a and 13a facing each other, so that the inversion of the lip portion 9 can be suppressed and the seal member 5 is prevented from falling off the raceway. can do. Accordingly, in order to prevent the lip portion from being reversed, it is not necessary to increase the lip rigidity by increasing the thickness of the lip portion. Therefore, the thickness of the lip portion 9 can be made thinner than that of the conventional one, and the sealing torque can be reduced.

Further, by inserting the base portion 6 of the seal member 5 into the fixed groove 13 provided on the peripheral surface of the convex side race ring, the annular wall portion 14 between the peripheral surface of the convex side race ring and the inner surface of the fixed groove 13 is formed. Since it fits in the fitting groove 10a of the base 6, the seal member 5 can be easily fixed to the convex raceway. Therefore, the number of assembly steps can be reduced. In this case, an adhesive or the like for fixing the seal member 5 is not necessary, and other components such as a lid for suppressing the seal are also unnecessary, so that the number of components can be reduced and the manufacturing cost can be reduced. The workability when replacing the worn seal member 5 is also greatly improved as compared with the prior art.

Of the base 6 of the seal member 5, the base inner side surface 6 a facing the bottom of the annular groove 12 has a shape connected by a single curved surface or a continuous curved surface having no inflection point. The rigidity can be increased and local deformation can be prevented. As shown in FIG. 2B, the angle α1 of the line connecting the axial inner side surface 7a of the main lip 7 and the base inner side surface 6a of the base 6 is set to 180 degrees or more and 270 degrees or less. The main lip 7 can be positively elastically deformed by applying an internal pressure to a portion P <b> 1 connecting the axial inner side surface 7 a and the base inner side surface 6 a of the base 6. Thereby, even when the catching amount of the base portion 6 is small with respect to the annular wall portion 14, the seal member 5 can be prevented from coming out on the base portion 6 side.

As shown in FIG. 2A, the surface S2 of the annular protrusion 16 extending the seal sliding side inclined portion 16a to the convex raceway side, and the seal fixing side inclined portion 13a of the fixing groove 13 is set to the concave side track. Since the seal sliding side inclined portion 16a and the seal fixing side inclined portion 13a are provided so as to intersect with the surface S1 extended to the ring side, the following effects are obtained. That is, the surface S2 obtained by extending the seal sliding side inclined portion 16a toward the convex raceway and the surface S1 obtained by extending the seal fixing side inclined portion 13a of the fixing groove 13 toward the concave raceway are close to one plane. When the internal pressure is applied to the seal member 5, the main lip 7 and the base portion 6 of the seal member 5 can be brought into contact with each other more reliably.

As shown in FIG. 2 (B), the thickness t1 of the main lip 7 is provided thinner than the radial thickness t2 of the seal body 11 of the base 6, so that the seal torque of the main lip 7 is reduced. When the internal pressure acts on the seal member 5, the main lip 7 can be positively elastically deformed. As a result, the main lip 7 is surely pressed against the seal sliding side inclined portion 16a of the annular projection 16 of the concave raceway ring, so that the base 6 is less likely to be caught with respect to the annular wall portion 14. However, it is possible to prevent the seal member 5 from coming out on the base 6 side.

Since the seal member 5 includes the secondary lip 8 that contacts the end surface 2d of the outer ring 2, the secondary lip 8 can further maintain the sealing performance of the seal member 5 and prevent grease leakage from the bearing space 4. Since the secondary lip 8 is in axial contact, the sealing torque can be reduced more than the lip portion in radial contact.

As another example of the seal structure, as in the second embodiment shown in FIG. 3, the base inner surface 6a facing the bottom of the annular groove 12 of the base 6 of the seal member 5 is intersected at an angle of 90 degrees or more and 180 degrees or less. It is good also as the shape connected with the some surface (two surfaces in the example of FIG. 3) which has angle (alpha) 2. The “intersection angle” α2 refers to an angle viewed from the inside of the seal member 5. In this case, the rigidity of the base 6 of the seal member 5 can be increased and local deformation can be prevented.

As in the third embodiment shown in FIG. 4, the bottom surface 12 a of the fitting groove of the base portion 6 of the seal member 5 may be brought into contact with the base portion 6 of the seal member 5, or as in the fourth embodiment shown in FIG. 5. Furthermore, the bearing space side groove side surface 12 b of the base portion 6 of the seal member 5 and the base portion 6 of the seal member 5 may be brought into contact with each other. In the third embodiment, the bottom surface 12 a is a bottom surface of the annular groove 12 provided on the outer peripheral surface of the inner ring 1, and in the fourth embodiment, the bearing space side groove side surface 12 b is an annular surface provided on the outer peripheral surface of the inner ring 1. It is an inner surface on the inner side in the axial direction at the bottom of the groove 12.

As in the fifth embodiment shown in FIG. 6, the bottom surface 12 a of the fitting groove and the bearing space side groove side surface 12 b may be brought into contact with the seal base 6. The configurations of the third to fifth embodiments shown in FIGS. 4 to 6 can increase the friction coefficient, stabilize the fixation of the seal base 6, and enhance the suppression of grease leakage from the fixed portion. . Further, since the tightness of the seal lip can be maintained, the sealing performance can be stabilized.

7 and 8 show an example of a wind turbine for wind power generation. As shown in these drawings, in the wind turbine 21, a nacelle 23 is provided on a support base 22 so as to be horizontally rotatable, a main shaft 25 is rotatably supported in a casing 24 of the nacelle 23, and a casing 24 of the main shaft 25 is supported. A blade 26 which is a swirl blade is attached to one end protruding outward. The other end of the main shaft 25 is connected to the speed increaser 27, and the output shaft 28 of the speed increaser 27 is coupled to the rotor shaft of the generator 29.

As shown in FIG. 8, the nacelle 23 is rotatably supported by a swing bearing BR1. In the slewing bearing of any one of the embodiments described above, for example, a slewing bearing BR1 for the nacelle 23 having a gear or the like provided on the outer peripheral surface of the outer ring 2 is used. Further, as shown in FIG. 7, a plurality of drive sources 30 are installed in the casing 24, and pinion gears are fixed to the drive sources 30 via a reduction gear (not shown). It arrange | positions so that the said gear of the outer ring | wheel 2 (FIG. 1) may mesh | engage with the said pinion gear. For example, the outer ring 2 is connected and fixed to the support base 22 by a plurality of through holes 2 b, and the inner ring 1 is fixed to the casing 24. The plurality of drive sources 30 are driven in synchronization, and this turning driving force is transmitted to the outer ring 2. Therefore, the nacelle 23 can turn relative to the support base 22.

The blade 26 is rotatably supported by the slewing bearing BR2. As this slewing bearing BR2, in the slewing bearing of any of the embodiments described above, for example, a structure in which a gear is provided on the inner peripheral surface of the inner ring 1 is applied. As shown in FIG. 8, a driving source for rotating the blade 26 is provided at the protruding end portion 25 a of the main shaft 25. The outer ring 2 of the slewing bearing is connected and fixed to the distal end portion 25a, and a gear attached to the inner peripheral surface of the inner ring 1 is engaged with a pinion gear of the drive source 30 (FIG. 7). By driving the drive source 30 and transmitting the turning driving force to the inner ring 1, the blade 26 can turn. Therefore, the slewing bearing BR2 can support the wind turbine blade 26 with respect to the main shaft 25 so as to be rotatable about an axis L2 substantially perpendicular to the main shaft axis L1. In this way, the angle of the blade 26 and the direction of the nacelle 23 can be changed at any time according to the wind condition.

When the slewing bearing having any one of the above seal structures is used in a wind turbine for wind power generation, it is possible to prevent the lip portion 9 of the seal member 5 from being reversed and the seal member 5 from dropping off when the internal pressure is increased. As a result, the sealing performance of the seal member 5 can be maintained and grease leakage can be prevented, so that the surrounding environment can be protected and the bearing life can be extended. Further, since the sealing torque can be reduced, it is not necessary to increase the capacity of the turning torque. Therefore, it is possible to reduce the size of the drive source and reduce the manufacturing cost.

These slewing bearings are used to slew various machines used outdoors or indoors, such as hydraulic excavators other than those for wind power generation, construction machines such as cranes, rotary tables for machine tools, gun seats, parabolic antennas, and lifting machines. It can also be applied to parts. The slewing bearing may be one in which the inner and outer rings have double-row raceway grooves or a cylindrical roller type (three-row cylindrical roller, cross roller).

Next, application examples 1 to 4 of the present invention will be described with reference to FIGS. In the application examples shown in these drawings, the annular protrusion 16 and the seal sliding side inclined portion 16a in each of the above-described embodiments are omitted, and other configurations are the same as those of the above-described embodiments. Parts that are the same as or correspond to those in FIG.

In the application example 1 shown in FIGS. 9 and 10, as shown in FIG. 10, the main lip 7 of the lip portion 9 includes a lip body portion 7b connected to the base portion 6, and a lip protrusion portion 7c protruding from the lip body portion 7b. And have. The lip body portion 7b and the lip protruding portion 7c extend as an entire main lip so as to be positioned on the inner side in the axial direction of the bearing space toward the tip. The lip protrusion 7c is thinner than the lip body 7b. Further, the lip protrusion 7c is formed in a tapered shape of the cross section that decreases in thickness toward the tip, in other words, a wedge shape.

In the case of this application example 1, for example, when internal pressure is applied to the seal member 5 by adding grease to the inside of the bearing from the grease supply pipe, the lip protruding portion 7c of the main lip 7 becomes the seal sliding contact surface portion 2c. Pressed against. At this time, since the lip protrusion 7c is formed in the aforementioned tapered shape in cross section, the entire lip protrusion 7c is firmly pressed along the seal sliding contact surface portion 2c.

Describe the effects. For example, when the internal pressure is applied to the seal member 5 by additionally supplying grease into the bearing from the greasing pipe, the main lip 7 is pressed against the seal sliding contact surface portion 2c of the concave raceway, and the base 6 Is pressed against the seal fixing side inclined portion 13a. At this time, since the cross-sectional shape of the base inner side surface 6a facing the bottom of the annular groove 12 of the convex raceway in the base portion 6 of the seal member 5 is a shape made of one convex curve, The rigidity can be increased and local deformation can be prevented. Thereby, reversal of the lip portion 9 can be suppressed, and the seal member 5 can be prevented from falling off the raceway. Since it can withstand the internal pressure and the reversal of the lip portion 9 can be suppressed, it is not necessary to increase the lip rigidity by increasing the thickness of the lip portion 9. Therefore, the thickness of the lip portion 9 can be made thinner than the conventional one, and the seal torque during the bearing operation can be reduced. In addition, the sealing performance of the sealing member 5 is maintained. Since the lip protrusion 7c has a tapered cross section, when the internal pressure is applied to the seal member 5, the entire lip protrusion 7c is firmly pressed along the seal sliding contact surface portion 2c. 9 can be more reliably suppressed.

Further, since the annular wall portion 14 between the peripheral surface of the convex raceway ring and the inner surface of the fixing groove 13 is fitted into the fitting groove 10a of the base portion 6, the seal member 5 is easily fixed to the convex raceway ring. can do. Therefore, the number of assembly steps and the number of parts can be reduced, and the manufacturing cost can be reduced.

As described with reference to FIG. 2B, the angle α1 of the intersection line connecting the axial inner side surface 7a of the main lip 7 and the base inner side surface 6a of the base 6 is set to 180 degrees or more and 270 degrees or less. 7 can be positively elastically deformed. Thereby, even when the catching amount of the base portion 6 is small with respect to the annular wall portion 14, the seal member 5 can be prevented from coming out on the base portion 6 side.

The thickness t1 of the main lip 7 is provided thinner than the radial thickness t2 of the seal body 11 of the base 6, and the thickness of the lip protrusion 7c is provided thinner than the thickness of the lip body 7b. Therefore, the sealing torque of the main lip 7 can be reduced, and when the internal pressure is applied to the seal member 5, the main lip 7 can be positively elastically deformed. As a result, the entire lip projecting portion is more firmly pressed along the seal sliding contact surface portion 2c, so that even if the hooking amount of the base portion 6 is small with respect to the annular wall portion 14, the base portion 6 side of the seal member 5 Can be prevented from coming off.

Since the seal member 5 includes the auxiliary lip 8 that is in axial contact with the end surface 2d of the outer ring 2, the auxiliary lip 8 further maintains the sealing performance of the seal member 5 and has a sealing torque higher than that of the lip portion that is in radial contact. Reduction can be achieved.

As another example of the seal structure, as in Application Example 2 shown in FIG. 11, the cross-sectional shape of the base inner side surface 6a facing the bottom of the annular groove 12 in the base 6 of the seal member 5 is continuous without an inflection point. It is good also as the shape connected with the convex curve Lb, Lc, Ld which was made. These convex curves Lb, Lc, and Ld each form a convex curved surface inward in the radial direction. Also in this case, the rigidity of the entire seal member 5 can be increased and local deformation can be prevented. Thereby, reversal of the lip portion 9 can be suppressed, and the seal member 5 can be prevented from falling off the raceway.

FIG. 12 shows an application example 3. This application example 3 corresponds to the second embodiment shown in FIG. 3 and has the same configuration except that the annular projecting portion 16 and the seal sliding side inclined portion 16a are not provided. The effect is also substantially the same as in the second embodiment, and a description thereof is omitted.

FIG. 13 shows an application example 4. This application example 4 corresponds to the fifth embodiment shown in FIG. 6 and has the same structure except that the annular protrusion 16 and the seal sliding side inclined portion 16a are not provided. The effect is also substantially the same as in the fifth embodiment, and the description is omitted.

Although not shown, the base 6 is not brought into contact with the inner side surface 15 on the axially inner side at the bottom, and the groove bottom 12a and the seal base 6 at the bottom are brought into contact as shown in FIG. 4 showing the third embodiment. Alternatively, the base 6 may not be brought into contact with the groove bottom surface 12a, but the inner surface 15 on the inner side in the axial direction at the bottom and the seal base 6 may be brought into contact as shown in FIG. 5 showing the fourth embodiment. In these cases, although the friction coefficient between the bottom and the base 6 of the seal member 5 is smaller than in the case of FIG. 13, the base 6 of the seal member 5 is stably fixed and the grease leakage from the annular groove 12 is suppressed. Can be strengthened.

Needless to say, the seal structures and the slewing bearings of the slewing bearings of the application examples 1 to 4 can be applied to the wind turbine of the wind power generator and other uses as in the above embodiments.

Application examples 1 to 4 that do not have the “annular protrusion 16” as a requirement in each embodiment according to the present invention include the following modes.
[Aspect 1]
In the seal structure of the slewing bearing according to the first aspect, raceway grooves are formed in the inner and outer ring raceways, a plurality of rolling elements are provided between the raceway grooves of the inner and outer races, and at the axial ends of the inner and outer races. In addition, a step that is uneven in the axial direction is provided between the inner and outer rings, and includes an elastic seal member that seals the axial end of the inner and outer rings having the step,
The seal member includes a base fixed to a portion protruding from the concave raceway of the convex raceway that is the convex side of the step, and one or more that are in contact with the concave raceway that is the concave side of the step. A lip portion, and one of the lip portions includes a main lip that extends in an inclined manner so as to be located on the inner side in the axial direction of the bearing space toward the tip.
Provided on the peripheral surface of the concave bearing ring on the bearing space side is a seal slidable contact surface portion that slidably contacts the main lip of the seal member;
An annular groove is provided on the peripheral surface of the convex raceway, and a fixing groove is provided on an outer surface in the axial direction at the bottom of the annular groove, and the base portion of the seal member includes the peripheral surface of the convex raceway and the circumferential surface. There is a groove for fitting into which the annular wall portion that is a portion between the inner surface of the fixed groove is fitted, and the groove side surface on the bearing space side of the inner surface of the fixed groove moves away from the bearing space toward the groove bottom side portion. A seal fixing side inclined portion that is inclined so as to be located on the side,
Of the base of the seal member, the cross-sectional shape of the base inner surface facing the bottom of the annular groove of the convex race is connected by a single convex curve or a continuous convex curve having no inflection point. The shape is different.
[Aspect 2]
In the seal structure of the slewing bearing according to the first aspect, the cross-sectional shape of the inner surface of the base facing the bottom of the annular groove of the convex raceway of the base of the seal member has an intersection angle of 90 degrees or more and 180 degrees or less. The shape was connected by a plurality of lines.
[Aspect 3]
In the seal structure of the slewing bearing according to the aspect 1, the main lip has a lip body part connected to a base part, and a lip protrusion part protruding from the lip body part. The lip protrusion part is formed from the lip body part. Also reduced the thickness.
[Aspect 4]
In the seal structure of the slewing bearing according to aspect 2, the angle of the line of intersection connecting the axial inner side surface of the main lip and the base inner side surface of the base portion is set to 180 degrees or more and 270 degrees or less.
[Aspect 5]
In the seal structure of the slewing bearing according to the first aspect, the inner side surface on the inner side in the axial direction at the bottom of the annular groove of the convex bearing ring is inclined so as to be positioned on the side away from the bearing space toward the groove bottom side portion. A cross-sectional shape was formed.
[Aspect 6]
In the seal structure of the slewing bearing according to the aspect 1, the bottom of the annular groove in the convex race and the base of the seal member are brought into contact with each other.
[Aspect 7]
In the slewing bearing seal structure according to aspect 1, the seal member is made of nitrile or chloroprene.
[Aspect 8]
In the seal structure of the slewing bearing according to the first aspect, the seal member includes, as one of the lip portions, a sub lip branched from the base portion separately from the main lip and in contact with the end surface of the concave bearing ring.
[Aspect 9]
In the seal structure of the slewing bearing according to the aspect 1, the slewing bearing to which any one of the above-described aspects is applied.

As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily assume various changes and modifications within the obvious scope by looking at the present specification. Accordingly, such changes and modifications are to be construed as within the scope of the invention as defined by the appended claims.

DESCRIPTION OF SYMBOLS 1 ... Inner ring 2 ...

Outer ring

1a, 2a ... Raceway groove 2c ... Seal sliding contact surface part 4 ... Bearing space 5 ... Seal member 6 ... Base part 6a ... Base inner side surface 7 ... Main lip 7a ... Axial inner side surface 7c ... Lip protrusion part 8 ... sub lip 9 ... lip part 10a ... fitting groove 12 ... annular groove 13 ... fixed groove 13a ... seal fixing side inclined part 14 ... annular wall part 16 ... annular protruding part 16a ... seal sliding side inclined part 23 ... nacelle 26 ... Blade BR1, BR2 ... Slewing bearing

Claims

A raceway groove is formed in each of the races of the inner ring and the outer ring, and a plurality of rolling elements are provided between the raceway grooves of the inner and outer rings, and the inner and outer rings are uneven in the axial direction between the inner and outer rings. A step is provided, and includes an elastic sealing member that seals the axial end of the inner and outer rings having the step,
The seal member includes a base fixed to a portion protruding from the concave raceway of the convex raceway that is the convex side of the step, and one or more that are in contact with the concave raceway that is the concave side of the step. A lip portion, and one of the lip portions includes a main lip that extends in an inclined manner so as to be located on the inner side in the axial direction of the bearing space toward the tip.
Provided on the peripheral surface of the concave bearing ring on the bearing space side is a seal slidable contact surface portion that slidably contacts the main lip of the seal member;
An annular projecting portion projecting in the radial direction is provided on the end side of the seal sliding contact surface portion on the peripheral surface of the concave raceway,
Provided on the inner surface in the axial direction of the annular protrusion is a seal sliding side inclined portion that is inclined so as to be positioned on the outer side in the axial direction toward the protruding tip,
An annular groove is provided on the peripheral surface of the convex raceway, and a fixing groove is provided on an outer surface in the axial direction at the bottom of the annular groove, and the base portion of the seal member includes the peripheral surface of the convex raceway and the circumferential surface. There is a groove for fitting into which the annular wall portion that is a portion between the inner surface of the fixed groove is fitted, and the groove side surface on the bearing space side of the inner surface of the fixed groove moves away from the bearing space toward the groove bottom side portion. A seal structure for a slewing bearing provided with a seal fixing side inclined portion that is inclined so as to be positioned on the side.
The base inner surface facing the bottom of the annular groove of the convex raceway ring in the base portion of the seal member according to claim 1 is connected with a single curved surface or a continuous curved surface having no inflection point. Slewing bearing seal structure.
In Claim 1, Of the base part of the said seal member, The shape which connected the inner surface of the base part which faces the bottom part of the said annular groove of the said convex side track ring with the several surface which has 90 degree or more and 180 degrees or less of intersection angles, Slewing bearing seal structure.
3. The seal structure for a slewing bearing according to claim 2, wherein an angle of an intersecting line connecting the axial inner side surface of the main lip and the base inner side surface of the base portion is 180 degrees or more and 270 degrees or less.
4. The seal structure for a slewing bearing according to claim 3, wherein an angle of an intersecting line connecting the axial inner side surface of the main lip and the base inner side surface of the base portion is 180 degrees or more and 270 degrees or less.
In Claim 1, the surface which extended the seal sliding side inclination part in the said cyclic | annular protrusion part to the convex side raceway side, and the surface which extended the seal fixed side inclination part of the said fixing groove to the concave side raceway side cross. Thus, the seal structure of the slewing bearing provided with the seal sliding side inclined portion and the seal fixing side inclined portion.
2. The seal structure of a slewing bearing according to claim 1, wherein the main lip is thinner than a base portion.
2. The seal structure for a slewing bearing according to claim 1, wherein the bottom surface of the fitting groove or the side surface of the bearing space side groove and the seal base are in contact with each other.
2. The seal structure of a slewing bearing according to claim 1, wherein the seal member is made of nitrile or chloroprene.
2. The seal structure for a slewing bearing according to claim 1, wherein the seal member includes, as one of the lip portions, a sub lip branched from the base portion separately from the main lip and in contact with the end surface of the concave bearing ring.
2. The seal structure for a slewing bearing according to claim 1, wherein an initial tightening margin of the main lip is 2 mm or more and 6 mm or less.
A slewing bearing to which the seal structure according to claim 1 is applied.
13. The slewing bearing according to claim 12, wherein the wind turbine blade is supported so as to be rotatable about an axis substantially perpendicular to the spindle axis with respect to the spindle.
13. The slewing bearing according to claim 12, wherein the nacelle of the windmill is slidably supported with respect to the support base.