JP2010048342A - Large-sized roller bearing, main shaft supporting structure of wind power generator, and rotary shaft supporting structure of tunnel boring machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a large-sized roller bearing preventing decrease in the function. <P>SOLUTION: The large-sized roller bearing 31 includes an outer ring 32 having an outer-diameter dimension of 2,500 mm, an inner ring 33 having an inner-diameter dimension of 2,000 mm, and a plurality of retainer segments 11a, 11d. Thermal linear expansion coefficients of the outer ring 32 and the inner ring 33 are 1×10<SP>-5</SP>-2×10<SP>-5</SP>/°C. The retainer segments 11a, 11d are made of resin containing filling material for lowering thermal linear expansion coefficients. The thermal linear expansion coefficients are 1×10<SP>-5</SP>-3×10<SP>-5</SP>/°C. In room temperature, a circumferential dimension R of a clearance 39 between the retainer segment 11a and the retainer segment 11d is larger than 0.075% and smaller than 0.12% of a circumference of a circle passing through the centers of the retainer segments 11a, 11d. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a large roller bearing, a main shaft support structure for a wind power generator, and a rotary shaft support structure for a tunnel excavator, and in particular, a large roller including a plurality of cage segments arranged in the circumferential direction to form one cage. The present invention relates to a bearing, a main shaft support structure of a wind power generator including such a large roller bearing, and a rotary shaft support structure of a tunnel excavator.

  The roller bearing is generally composed of an outer ring, an inner ring, a plurality of rollers disposed between the outer ring and the inner ring, and a cage that holds the plurality of rollers. The cage is usually made of a single piece, that is, a single annular part.

  A roller bearing that supports a main shaft of a wind power generator to which a blade for receiving wind is attached needs to receive a large load, so that the roller bearing itself is also large. If it does so, each structural member which comprises a roller bearing, such as a roller and a holder | retainer, will also become large sized, and production and assembly of a member will become difficult. In such a case, if each member can be divided, production and assembly are facilitated.

  Here, a technique related to a split type cage in which a cage included in a roller bearing is divided by a dividing line extending in a direction along the axis of rotation of the bearing is disclosed in European Patent Publication No. 1408248A2 (Patent Document 1). FIG. 12 is a perspective view showing a cage segment which is a split type cage disclosed in Patent Document 1. FIG. Referring to FIG. 12, the cage segment 101a includes a plurality of pillars 103a, 103b, 103c, 103d, 103e extending in a direction along the rotation axis of the bearing so as to form a plurality of pockets 104 for accommodating the rollers, It has the connection parts 102a and 102b extended in the circumferential direction so that the some pillar part 103a-103e may be connected.

FIG. 13 is a cross-sectional view showing a part of the tapered roller bearing including the cage segment 101a shown in FIG. The configuration of the tapered roller bearing 111 including the cage segment 101a will be described with reference to FIGS. 12 and 13. The tapered roller bearing 111 includes an outer ring 112, an inner ring 113, a plurality of tapered rollers 114, and a plurality of cones. It has a plurality of cage segments 101a, 101b, 101c, etc. for holding the rollers 114. The plurality of tapered rollers 114 are held by a plurality of cage segments 101a and the like in the vicinity of a PCD (Pitch Circle Diameter) 105 where the roller behavior is most stable. The cage segments 101a for holding the plurality of tapered rollers 114 are arranged so that the cage segments 101b and 101c having the same shape adjacent in the circumferential direction are in contact with the outermost pillar portions 103a and 103e in the circumferential direction. Has been. A plurality of cage segments 101 a, 101 b, 101 c, etc. are connected to each other and incorporated in the tapered roller bearing 111 to form one annular cage included in the tapered roller bearing 111.
European Patent Publication 1408248A2

  According to Patent Document 1, when the cage segments made of resin are arranged in the circumferential direction, the dimension of the last gap generated between the first cage segment and the last cage segment is determined as the cage segment. 0.15% or more and less than 1% of the circumference of a circle passing through the center of By configuring in this way, collision noise and the like when the cage segments collide with each other are prevented, and sticking between the cage segments during thermal expansion is prevented. In Patent Document 1, the cage segment is manufactured from polyphenylene sulfide (hereinafter referred to as “PPS”) or polyether ether ketone (hereinafter referred to as “PEEK”).

  Here, even if the clearance in the circumferential direction is set in such a numerical range, it is not possible to cope with the following problems noted by the inventor. FIG. 14 is a schematic sectional view showing a part of the tapered roller bearing 111 when the tapered roller bearing 111 is used as a bearing for supporting the main shaft of the wind power generator. For easy understanding, the gap 115 generated between the cage segments 101a and 101c is exaggerated and enlarged.

  Referring to FIG. 14, the main shaft 110 of the wind power generator supported by the tapered roller bearing 111 is used on the horizontal axis. When the tapered roller bearing 111 is used, the cage segments 101a to 101c revolve in a direction indicated by an arrow in FIG. 14, for example. The revolving motion of the cage segments 101a to 101c is performed such that each cage segment 101a to 101c sequentially pushes the adjacent cage segments 101a to 101c in the direction of the arrow. In this case, for example, the tapered roller or the cage segment 101a falls freely in the portion indicated by XII in FIG. Then, the cage segments 101a and 101c collide with each other to cause deformation of the cage segments 101a and 101c, wear of the end surfaces, collision noise, and the like, which may greatly reduce the function of the tapered roller bearing 111.

  When the tapered roller bearing 111 is used as a bearing for supporting the main shaft 110 of the wind power generator, the cage segments 101a to 101c themselves are large in size, so that a problem caused by a collision during free fall is great. Therefore, the gap size defined above is insufficient, and the circumferential gap needs to be further reduced. However, the resin cage segment is also affected by thermal expansion, and there is a limit to reducing the size of the circumferential clearance.

  An object of the present invention is to provide a large roller bearing capable of preventing a decrease in function.

  Another object of the present invention is to provide a main shaft support structure for a wind power generator capable of preventing a decrease in function.

  Still another object of the present invention is to provide a rotating shaft support structure for a tunnel excavator that can prevent a decrease in function.

The large roller bearing according to the present invention has an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a pocket for accommodating the rollers, and is successively connected in the circumferential direction between the outer ring and the inner ring. A plurality of cage segments arranged. The outer diameter of the outer ring is 1000 mm or more, and the inner diameter of the inner ring is 750 mm or more. The coefficient of linear expansion due to heat of the outer ring and the inner ring is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less, and the cage segment is made of resin containing a filler that reduces the coefficient of thermal expansion due to heat. And the linear expansion coefficient by the heat | fever is 1 * 10 < ^-5 > / degreeC or more and 3 * 10 < ^-5 > / degreeC or less. When a plurality of cage segments are arranged without gaps in the circumferential direction, there is a gap between the cage segment first arranged and the cage segment arranged last, and the circumferential direction of the gap at room temperature. Is greater than 0.075% and less than 0.12% of the circumference of a circle passing through the center of the cage segment.

  Thus, in the large roller bearing in which the outer diameter of the outer ring is 1000 mm or more and the inner diameter of the inner ring is 750 mm or more, the cage segment is made of a resin containing a filler that reduces the coefficient of thermal expansion due to heat. By doing so, the dimensional change by the thermal expansion of a cage segment can be made small. If it does so, the clearance of the circumferential direction which arises between holder | retainer segments can be made smaller than the range prescribed | regulated to patent document 1. FIG.

Further, by setting the coefficient of linear expansion due to heat of the outer ring, the inner ring, and the cage segment within the above range, a difference in coefficient of linear expansion due to heat of each bearing component member can be allowed in an actual use situation. In addition, the linear expansion coefficient by the heat | fever of PEEK mentioned above is about 4.7 * 10 < ^-5 > / degreeC, and the linear expansion coefficient by the heat | fever of PPS is about 5.0 * 10 < ^-5 > / ^degreeC .

  Specifically, the outer ring and the inner ring provided in the large roller bearing thermally expand due to temperature changes. Here, in consideration of the linear expansion coefficient due to the heat of the cage segment and the thermal expansion coefficient of the outer ring and the inner ring, the dimension of the clearance in the circumferential direction at room temperature in the actual use situation is the center of the cage segment. It can be reduced to 0.075% of the circumference of the passing circle. That is, by making the circumferential gap larger than 0.075% of the circumference, it is possible to avoid a state in which the circumferential dimension of the gap becomes negative and the cage segments are stuck and stuck together.

  Moreover, in the large roller bearing used for the above-mentioned application, it is preferable that the cage constituted by a plurality of cage segments increase the safety factor from the viewpoint of durability and reliability improvement. The value of the safety factor of the cage increases as the circumferential clearance becomes smaller. The safety factor of the cage is required to be 4.0 or more from the viewpoint of the fatigue strength of the material of the cage segment and the stress generated in the cage segment. Here, by making the circumferential dimension of the gap at room temperature smaller than 0.12% of the circumference of the circle passing through the center of the cage segment, the safety factor can be secured to 4.0 or more. If it does so, the strength malfunction by the collision of cage segments etc. including the above-mentioned problem can be avoided.

  As described above, in a large roller bearing in which the outer ring has an outer diameter of 1000 mm or more and the inner ring has an inner diameter of 750 mm or more, the cage segment is made of resin including a filler that reduces the coefficient of linear expansion due to heat. By setting the coefficient of linear expansion due to heat of the outer ring, the inner ring and the cage segment to the above range, and setting the clearance in the circumferential direction between the cage segments to the above range, there is a strong problem caused by the collision between the cage segments, etc. In addition, it is possible to prevent deformation due to circumferential tension between the cage segments. Accordingly, it is possible to prevent the function of the large roller bearing having such a cage segment from being deteriorated.

  Here, the cage segment is a unit body obtained by dividing one annular cage by a dividing line extending in a direction along the rotation axis of the bearing so as to have at least one pocket for accommodating the rollers. The first cage segment is the cage segment that is placed first when the cage segments are sequentially arranged in the circumferential direction, and the last cage segment is the adjacent cage segment. The cage segments are arranged last when they are brought into contact with each other and sequentially arranged in the circumferential direction. A plurality of cage segments are connected to the large roller bearing in a circumferential direction to form one annular cage.

  Preferably, the filler includes at least one of carbon fiber, glass fiber, graphite, carbon black, aluminum powder, iron powder, and molybdenum disulfide. Since such a filler has good affinity with the resin, the coefficient of linear expansion due to heat can be efficiently reduced.

  More preferably, the resin is polyamide (PA), polyacetal (POM), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), syndiotactic polystyrene (SPS), polyphenylene sulfide (PPS), polyether ether ketone ( PEEK), liquid crystal polymer (LCP), fluororesin, polyether nitrile (PEN), polycarbonate (PC), modified polyphenylene ether (mPPO), polysulfone (PSF), polyethersulfone (PES), polyarylate (PAR), At least one of the group consisting of polyamideimide (PAI), polyetherimide (PEI), and thermoplastic polyimide (PI) is included. Such a resin can appropriately include a filler to reduce the coefficient of thermal expansion due to heat to the above-described range.

  More preferably, the filling ratio of the filler in the resin is 20% by weight or more and 40% by weight or less. By setting the filling ratio of the filler in the resin within the above range, the coefficient of thermal expansion due to heat can be greatly reduced without causing other problems due to filling of the filler.

  More preferably, at room temperature, the circumferential dimension of the gap is greater than 0.075% and less than 0.09% of the circumference of a circle passing through the center of the cage segment. By doing so, the safety factor can be further increased.

  More preferably, the roller is a tapered roller. The roller bearing used for the main shaft of the wind power generator described above needs to receive a large moment load, thrust load, radial load, and the like. Here, when the roller is a tapered roller, a large moment load or the like can be received.

  More preferably, the large roller bearing supports a main shaft of a wind power generator that rotates with a blade that receives wind power. Such large roller bearings are suitable for supporting the main shaft of a wind power generator provided at a high place where replacement and maintenance are difficult.

  Moreover, a large roller bearing supports the rotating shaft with which the cutter head provided with the cutter which excavates earth and sand was provided in one end. Such a large roller bearing is suitable for supporting the rotating shaft of a tunnel excavator used in the ground where replacement and maintenance are difficult.

  Note that a seal that prevents foreign matter from entering the inside of the bearing may be provided between the outer ring and the inner ring. By comprising in this way, the penetration | invasion into the large roller bearing of foreign materials, such as excavated earth and sand and muddy water, can be prevented, for example. Therefore, a long life of the large roller bearing can be realized.

In another aspect of the present invention, a main shaft support structure of a wind power generator includes a blade that receives wind power, a main shaft that is fixed to the blade, and that rotates together with the blade, and is incorporated in a fixing member to support the main shaft rotatably. Including large roller bearings. The large roller bearing has an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a pocket for accommodating the rollers, and a plurality of rollers arranged sequentially in the circumferential direction between the outer ring and the inner ring. A cage segment. The coefficient of linear expansion due to heat of the outer ring and the inner ring is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less, and the cage segment is made of resin containing a filler that reduces the coefficient of thermal expansion due to heat. And the linear expansion coefficient by the heat | fever is 1 * 10 < ^-5 > / degreeC or more and 3 * 10 < ^-5 > / degreeC or less. When a plurality of cage segments are arranged without gaps in the circumferential direction, there is a gap between the cage segment first arranged and the cage segment arranged last, and the circumferential direction of the gap at room temperature. Is greater than 0.075% and less than 0.12% of the circumference of a circle passing through the center of the cage segment.

  Since the main shaft support structure of such a wind power generator includes a large roller bearing that prevents a decrease in function, it is possible to prevent a decrease in the function of the main shaft support structure itself of the wind power generator.

In yet another aspect of the present invention, the rotary shaft support structure of the tunnel excavator includes a cutter head provided with a cutter for excavating earth and sand, a rotary shaft provided with a cutter head at one end and rotating together with the cutter head, And a large roller bearing that is incorporated in the fixed member and rotatably supports the rotating shaft. The large roller bearing has an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a pocket for accommodating the rollers, and a plurality of rollers arranged sequentially in the circumferential direction between the outer ring and the inner ring. A cage segment. The coefficient of linear expansion due to heat of the outer ring and the inner ring is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less, and the cage segment is made of resin containing a filler that reduces the coefficient of thermal expansion due to heat. And the linear expansion coefficient by the heat | fever is 1 * 10 < ^-5 > / degreeC or more and 3 * 10 < ^-5 > / degreeC or less. When a plurality of cage segments are arranged without gaps in the circumferential direction, there is a gap between the cage segment first arranged and the cage segment arranged last, and the circumferential direction of the gap at room temperature. Is greater than 0.075% and less than 0.12% of the circumference of a circle passing through the center of the cage segment.

  Such a rotary shaft support structure of the tunnel excavator includes a large roller bearing that prevents the function from being deteriorated, and thus the function of the rotary shaft support structure itself of the tunnel excavator can be prevented from being deteriorated.

  According to the present invention, in a large roller bearing in which the outer ring has an outer diameter of 1000 mm or more and the inner ring has an inner diameter of 750 mm or more, the resin includes a filler that reduces the coefficient of thermal expansion of the cage segment material. By making the coefficient of linear expansion due to heat of the outer ring, the inner ring and the cage segment as described above, and by setting the circumferential clearance between the cage segments as described above, It is possible to prevent defects and the like and deformation due to circumferential tension between the cage segments. Accordingly, it is possible to prevent the function of the large roller bearing having such a cage segment from being deteriorated.

  In addition, since the main shaft support structure of the wind power generator includes a large roller bearing that prevents the function from being deteriorated, it is possible to prevent the function of the main shaft support structure itself of the wind power generator from being deteriorated.

  Moreover, since the rotating shaft support structure of such a tunnel excavator includes the large roller bearing which prevented the fall of the function, the fall of the function of the rotating shaft support structure itself of a tunnel excavator can be prevented.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 is a perspective view showing a cage segment 11a provided in a large tapered roller bearing according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of the cage segment 11a shown in FIG. 2 taken along a plane that includes the line III-III in FIG. 2 and that is perpendicular to the rotational axis of the bearing. FIG. 4 is a cross-sectional view of the cage segment 11a shown in FIG. 2 cut along a plane that passes through the center of the column portion 14a and is orthogonal to the circumferential direction. From the viewpoint of easy understanding, in FIGS. 3 and 4, the plurality of tapered rollers 12a, 12b, 12c held by the cage segment 11a are indicated by dotted lines. Moreover, PCD22 is shown with a dashed-dotted line.

  With reference to FIGS. 2-4, the structure of the cage segment 11a contained in a large tapered roller bearing is demonstrated first. The cage segment 11a has a shape in which one annular cage is divided by a dividing line extending in a direction along the rotation axis of the bearing so as to have at least one pocket for accommodating the rollers. The cage segment 11a includes four column portions 14a, 14b, 14c, 14d extending in the direction along the rotation axis of the bearing so as to form pockets 13a, 13b, 13c for receiving the tapered rollers 12a, 12b, 12c, It includes a pair of connecting portions 15a and 15b that are located at both ends in the axial direction and extend in the circumferential direction so as to connect the four column portions 14a to 14d. Here, the cage segment 11a is configured such that the column portions 14a and 14d are positioned at the outer end in the circumferential direction.

  The pair of connecting portions 15a and 15b has a predetermined curvature in the circumferential direction so that when the plurality of cage segments 11a are incorporated in the large tapered roller bearing, they form a single annular cage in the circumferential direction. Has a radius. Of the pair of connecting portions 15a and 15b, the radius of curvature of the connecting portion 15a located on the small diameter side of the tapered rollers 12a to 12c is smaller than the radius of curvature of the connecting portion 15b located on the large diameter side of the tapered rollers 12a to 12c. It is configured.

  Of the column portions 14a and 14b located on both sides in the circumferential direction of the pocket 13a and the column portions 14c and 14d located on both sides in the circumferential direction of the pocket 13c, the cage segment 11a is disposed on the inner diameter side of the side wall surfaces of the column portions 14a to 14d. The guide claws 17a, 17b, 17c, and 17d on the inner diameter side that restrict the movement of the outer diameter in the radial direction are provided. The guide claws 17a to 17d are in contact with the tapered rollers 12a and 12c accommodated in the pockets 13a and 13c on the inner diameter side. Further, of the column portions 14b and 14c located on both sides in the circumferential direction of the pocket 13b, an outer diameter that restricts the movement of the cage segment 11a inward in the radial direction is provided on the outer diameter side of the side wall surface of the column portions 14b and 14c. Side guide claws 18b and 18c are provided. The guide claws 18b and 18c are in contact with the tapered roller 12b accommodated in the pocket 13b on the outer diameter side. Each of the guide claws 17a to 17d, 18b, and 18c has a shape protruding toward the pockets 13a to 13c. Moreover, in the cross section shown in FIG. 3, the guide surfaces of the guide claws 17a to 17d, 18b, and 18c have a circular arc cross section and are shaped along the rolling surfaces of the tapered rollers 12a to 12c. Thus, by providing the guide claws 17a to 17d, 18b, and 18c on the inner diameter side and the outer diameter side, the cage segment 11a is brought into contact with the guide surfaces of the guide claws 17a to 17d, 18b, and 18c to provide roller guides. be able to. In addition, the end surfaces 21a and 21b on the outer side in the circumferential direction of the column portions 14a and 14d located on the outer side in the circumferential direction are flat.

  Here, the cage segment 11a is made of a resin containing a filler that reduces the coefficient of linear expansion due to heat. By doing so, the difference in coefficient of linear expansion due to heat with the bearing components such as the outer ring constituting the large tapered roller bearing can be reduced as will be described later. Can be reduced.

  The resin is polyamide (PA), polyacetal (POM), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), syndiotactic polystyrene (SPS), polyphenylene sulfide (PPS), polyether ether ketone (PEEK). , Liquid crystal polymer (LCP), fluororesin, polyether nitrile (PEN), polycarbonate (PC), modified polyphenylene ether (mPPO), polysulfone (PSF), polyethersulfone (PES), polyarylate (PAR), polyamideimide At least one of the group consisting of (PAI), polyetherimide (PEI), and thermoplastic polyimide (PI) is included. Such a resin can appropriately include a filler to reduce the coefficient of thermal expansion due to heat to the above-described range. In addition, you may combine multiple types of above-described resin.

Here, the resin is preferably PEEK. The coefficient of linear expansion due to heat of PEEK itself is about 4.7 × 10 ⁻⁵ / ° C., and it becomes easy to reduce the coefficient of linear expansion due to heat by including a filler.

  The filler contains at least one of carbon fiber, glass fiber, graphite, carbon black, aluminum powder, iron powder, and molybdenum disulfide. Since such a filler has good affinity with the resin, the coefficient of linear expansion due to heat can be efficiently reduced. Note that a plurality of fillers of the type described above may be filled.

Here, the coefficient of linear expansion due to heat of the cage segment 11a is 1 × 10 ⁻⁵ / ° C. or more and 3 × 10 ⁻⁵ / ° C. or less. In this way, by setting the coefficient of linear expansion due to heat of the cage segment 11a within the above range, a difference in coefficient of linear expansion due to heat from a bearing constituent member such as an outer ring constituting the large tapered roller bearing is allowed in an actual use situation. be able to. Specifically, it will be described later.

  The filling ratio of the filler in the resin is preferably 20% by weight or more and 40% by weight or less. By doing so, the linear expansion coefficient due to the heat of the resin can be greatly reduced without causing other problems due to filling of the filler, for example, insufficient strength due to excessive filling amount.

  Since a plurality of cage segments 11a are provided in one large tapered roller bearing, an improvement in productivity is required. However, by configuring in this way, cages having the same shape in large quantities by injection molding or the like. It becomes easy to manufacture the segment.

Here, specifically, the cage segment 11a is preferably made of PEEK containing 30% by weight of carbon fiber as a filler and having a coefficient of linear expansion due to heat of 1.5 × 10 ⁻⁵ / ° C. Such a cage segment 11a has a PEEK cage segment with a thermal linear expansion coefficient of 4.7 × 10 ⁻⁵ / ° C. and a thermal linear expansion coefficient of 5.0 × 10 ⁻⁵ / ° C. It differs greatly from a PPS cage segment in terms of the coefficient of thermal expansion due to heat.

  Next, the structure of the large tapered roller bearing including the cage segment 11a described above will be described. FIG. 5 is a schematic sectional view of the large tapered roller bearing 31 in which a plurality of cage segments 11a, 11b, 11c, 11d and the like are arranged in the circumferential direction, as viewed from the axial direction. 6 is an enlarged cross-sectional view of a portion indicated by VI in FIG. Here, since the cage segments 11b, 11c, and 11d have the same shape and the same material as the cage segment 11a, description thereof is omitted. In FIG. 5, tapered rollers held by the cage segment 11a and the like are omitted. In addition, here, among the plurality of cage segments 11a to 11d, the cage segment arranged first is the cage segment 11a, and the cage segment arranged last is the cage segment 11d.

5 and 6, large tapered roller bearing 31 includes an outer ring 32, an inner ring 33, a plurality of tapered rollers 34, and a plurality of cage segments 11a to 11d. Here, the outer diameter of the outer ring 32 is 2500 mm, and the inner diameter of the inner ring 33 is 2000 mm. Further, the coefficient of linear expansion due to heat of the outer ring 32 and the inner ring 33 is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less. As a specific material for the outer ring 32 and the inner ring 33, for example, case-hardened steel having a thermal linear expansion coefficient of about 1.12 × 10 ⁻⁵ / ° C. is selected.

  The cage segments 11a to 11d are sequentially connected in the circumferential direction and arranged without gaps. Here, first, the cage segment 11a is arranged first, and then the end surface 21a of the cage segment 11a and the cage segment 11b so that the cage segment 11b abuts the cage segment 11a. It arrange | positions so that the end surface 21c may contact | abut. Thereafter, the cage segment 11c is arranged so as to abut the cage segment 11b, specifically, the end surface 21d of the cage segment 11b and the end surface 21e of the cage segment 11c are abutted. The segments are arranged, and finally the cage segment 11d is arranged. In this way, the cage segments 11a to 11d are arranged in the circumferential direction. In this case, there is a circumferential gap 39 between the first cage segment 11a and the last cage segment 11d.

  Next, the circumferential clearance between the first cage segment 11a and the last cage segment 11d will be described. FIG. 1 is an enlarged cross-sectional view of a portion indicated by I in FIG. Here, the circumferential dimension R of the gap 39 is set to be larger than 0.075% and smaller than 0.12% of the circumference of a circle passing through the centers of the cage segments 11a to 11d. In this case, the circumferential lengths of the cage segments 11a to 11d may be adjusted so that the circumferential dimension R of the gap 39 falls within the above range, or the cage segments 11a to 11c may be adjusted. When arranging the last cage segment 11d in sequence, the end face 21f may be trimmed to adjust the dimensions so that it falls within the above range.

  FIG. 7 is a graph showing the relationship between the ratio of the gap 39 and the safety factor of the cage. With reference to FIG. 1 and FIG. 7, the safety factor of the cage constituted by the plurality of cage segments 11 a to 11 d is generated in the fatigue strength of the material of the cage segments 11 a to 11 d and the cage segments 11 a to 11 d. From the viewpoint of stress and the like, 4.0 or more is required. Here, by making the circumferential dimension of the gap 39 smaller than 0.12% of the circumference, the safety factor can be secured to 4.0 or more. If it does so, the intensity | strength malfunction by the collision etc. of cage | basket segments 11a-11d can be avoided.

Here, the linear expansion coefficient Kb due to heat of the cage segment 11a is about 1.5 × 10 ⁻⁵ / ° C. On the other hand, when the outer ring 32 and the inner ring 33 are case-hardened steel, the coefficient of linear expansion Ka due to the heat is about 1.12 × 10 ⁻⁵ / ° C. Here, assuming that the temperature rise is Δt and the difference in expansion amount of each member at the time of temperature rise is δ, the difference in expansion amount δ is expressed by the equation (1).

この場合、仮に保持器セグメント１１ａのみが５０℃上昇していた場合であっても、膨張量の差δは、０．０７５％となる。また、焼き嵌めで大型円錐ころ軸受３１をΔｔ＝１００℃に加熱した場合であっても、膨張量の差δは、０．０３５％となる。したがって、実使用状況において、０．０７５％よりも大きくすることにより、外輪３２や内輪３３等の軸受構成部材と保持器セグメント１１ａ〜１１ｄとの熱膨張の差を許容することができる。そうすると、すき間３９の周方向の寸法が負になって保持器セグメント１１ａ〜１１ｄ同士が突っ張る状態を回避することができる。そうすると、保持器セグメント１１ａ〜１１ｄの突っ張りあいによる変形を防止することができる。

In this case, even if only the cage segment 11a rises by 50 ° C., the difference in expansion amount δ is 0.075%. Even when the large tapered roller bearing 31 is heated to Δt = 100 ° C. by shrink fitting, the difference in expansion amount δ is 0.035%. Therefore, in an actual use situation, by making it larger than 0.075%, a difference in thermal expansion between the bearing constituent members such as the outer ring 32 and the inner ring 33 and the cage segments 11a to 11d can be allowed. Then, it is possible to avoid a state in which the circumferential dimension of the gap 39 becomes negative and the cage segments 11a to 11d are stretched. If it does so, the deformation | transformation by the tension | tensile_strength of the holder | retainer segments 11a-11d can be prevented.

  As described above, in the large tapered roller bearing 31 in which the outer diameter of the outer ring is 2500 mm and the inner diameter of the inner ring is 2000 mm, the material of the cage segments 11a to 11d includes a filler that reduces the coefficient of linear expansion due to heat. The outer ring 32, the inner ring 33, and the cage segments 11a to 11d with the coefficient of linear expansion due to heat are in the above range, and the clearance 39 in the circumferential direction between the cage segments 11a to 11d is in the above range. It is possible to prevent strength problems caused by the collision between the cage segments and deformation caused by the circumferential tension between the cage segments 11a to 11d. Accordingly, it is possible to prevent the function of the large tapered roller bearing 31 including such cage segments 11a to 11d from being deteriorated.

  In the above embodiment, a spacer for adjusting the dimension R of the circumferential clearance 39 is applied to the last cage segment 11d between the first cage segment 11a and the last cage segment 11d. You may decide to arrange so that it may touch. In this case, a gap 39 is generated between the spacer and the first cage segment 11a. By configuring in this way, it becomes easier to set the dimensions of the first retainer segment 11a, the last retainer segment 11d, and the circumferential clearance 39 within the above range. In this case, the spacer should be interpreted as a cage segment. Moreover, since the dimension of the circumferential direction of such a spacer is minute in the dimension of the circumferential direction in which the cage segments 11a to 11d are continuous, the same material as the cage segments 11a to 11d may be used. It may be made of resin or may be made of simple resin.

  8 and 9 show an example of a main shaft support structure of a wind power generator in which a large tapered roller bearing according to an embodiment of the present invention is applied as a main shaft support bearing 55. FIG. The casing 53 of the nacelle 52 that supports the main components of the main shaft support structure is installed on the support base 50 via a swivel bearing 51 at a high position so as to be horizontally rotatable. A main shaft 56 that fixes a blade 57 that receives wind power to one end is rotatably supported in a casing 53 of the nacelle 52 via a main shaft support bearing 55 incorporated in a bearing housing 54. Is connected to the speed increaser 58, and the output shaft of the speed increaser 58 is coupled to the rotor shaft of the generator 59. The nacelle 52 is turned at an arbitrary angle by the turning motor 60 via the speed reducer 61.

The main shaft support bearing 55 incorporated in the bearing housing 54 is a large tapered roller bearing according to an embodiment of the present invention, and includes an outer ring, an inner ring, a plurality of rollers disposed between the outer ring and the inner ring, and a roller. And a plurality of cage segments that are sequentially arranged in the circumferential direction between the outer ring and the inner ring. The coefficient of linear expansion due to heat of the outer ring and the inner ring is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less, and the cage segment is made of resin containing a filler that reduces the coefficient of thermal expansion due to heat. And the linear expansion coefficient by the heat | fever is 1 * 10 < ^-5 > / degreeC or more and 3 * 10 < ^-5 > / degreeC or less. When a plurality of cage segments are arranged without gaps in the circumferential direction, there is a gap between the cage segment first arranged and the cage segment arranged last, and the circumferential direction of the gap at room temperature. Is greater than 0.075% and less than 0.12% of the circumference of a circle passing through the center of the cage segment.

  Such a large tapered roller bearing is suitable for supporting the main shaft of a wind power generator provided at a high place where replacement and maintenance are difficult. Further, the main shaft support bearing 55 needs to receive a large moment load, a thrust load, a radial load and the like in order to support the main shaft 56 that fixes the blade 57 that receives a large wind force at one end. Here, when the roller is a tapered roller, a large moment load or the like can be received.

  Moreover, since the main shaft support structure of such a wind power generator includes a large tapered roller bearing that prevents the function from being deteriorated, it is possible to prevent the function of the main shaft support structure itself of the wind power generator from being deteriorated.

  FIG. 10 shows an example of a rotary shaft support structure of a tunnel excavator in which a large tapered roller bearing according to an embodiment of the present invention is applied as a bearing that supports the rotary shaft. Referring to FIG. 10, a rotary shaft support structure 71 of a tunnel excavator includes a cutter head 73 provided with a cutter 72 for excavating earth and sand, and a rotary shaft provided with a cutter head 73 at one end and rotating together with the cutter head 73. 74 and a large double-row tapered roller bearing 81 that is incorporated in the fixing member 77 and rotatably supports the rotating shaft 74 via the ring member 78. The large double-row tapered roller bearing 81 that supports the rotating shaft 74 has a configuration in which the large tapered roller bearing described above is double-rowed. The cutter head 73 and the rotary shaft 74 are also supported by the cutter head support portion 75 as a whole.

  The rotation shaft 74 is rotated by the motor 76, and the cutter head 73 provided at one end thereof rotates. Then, the plurality of cutters 72 provided at the tip of the cutter head 73 excavate the front face. In this way, while excavating the front face, the tunnel excavator is advanced to form a tunnel. The excavated earth and sand are carried backward with respect to the traveling direction and removed.

  Such a large double row tapered roller bearing 81 is suitable for supporting the rotary shaft 74 of a tunnel excavator used in the ground where replacement and maintenance are difficult. Further, the large double row tapered roller bearing 81 that supports the rotating shaft 74 needs to receive a large thrust load or moment load generated when crushing hard rock or the like. Here, by configuring the large double row tapered roller bearing 81 from the large tapered roller bearing described above, the large double row tapered roller bearing 81 can receive a large thrust load or moment load. Therefore, the rotary shaft support structure 71 of the tunnel excavator including such a large double row tapered roller bearing 81 can also receive a large thrust load and moment load. In addition, since the cage is divided, it is possible to follow the deformation of the race such as the outer ring.

  Further, since the rotary shaft support structure 71 of the tunnel excavator includes the large double row tapered roller bearing 81 that prevents the function from being lowered, the function of the rotary shaft support structure 71 itself of the tunnel excavator is prevented from being lowered. be able to.

  Here, a seal may be provided on the large double row tapered roller bearing 81 in order to prevent the excavated earth and sand from entering the large double row tapered roller bearing 81. FIG. 11 is a cross-sectional view showing a part of the large double row tapered roller bearing 81 described above. Referring to FIG. 11, large double-row tapered roller bearing 81 is arranged between outer ring 82, left and right inner rings 83a and 83b arranged so that the end surfaces on the small diameter side face each other, and left and right inner rings 83a and 83b. The inner ring spacer 86, the plurality of tapered rollers 84a, 84b disposed between the outer ring 82 and the left and right inner rings 83a, 83b, and pockets for holding the plurality of tapered rollers 84a, 84b in the left and right rows. And a plurality of cage segments 85a and 85b sequentially arranged in the circumferential direction between the outer ring 82 and the left and right inner rings 83a and 83b, and the first cage that is circumferentially arranged in the left and right rows. The tapered rollers 84a and 84b are disposed between two adjacent cage segments 85a and 85b except between the segment and the last cage segment. Between the outer ring 82 and the left and right inner rings 83a and 83b, a seal 91 is provided to prevent intrusion of earth and sand into the large double row tapered roller bearing 81. Here, the seal 91 provided on the inner ring 83a side will be described. However, since the seal 91 provided on the inner ring 83b side has the same configuration, the description thereof is omitted.

  The seal 91 is annular, has a substantially L-shaped cross section, and has a rigid core metal part 92; a rubber part 93 that is attached to the core metal part 92 and has elasticity; and a spring 94 that can contract toward the inner diameter side; Is provided. The rubber portion 93 is provided with a lip portion 95 that nips with one inner ring 83 a with an appropriate pressure, and the spring 94 is disposed on the outer diameter side of the lip portion 95. The metal core portion 92 is attached to the inner diameter surface 90 of the one end portion 89 of the outer ring 82 so that the lip portion 95 provided in the rubber portion 93 nips with the outer diameter surface 88 on the large collar 87 side of the inner ring 83a. . The lip portion 95 is maintained in a nip state with the inner ring 83 a by the spring 94. In this way, the large double row tapered roller bearing 81 is sealed by the seal 91.

  By comprising in this way, the penetration | invasion in the large double row tapered roller bearing 81, such as earth and sand and muddy water excavated by the cutter 72 and conveyed back, can be prevented. If it does so, since the damage of the bearing member by the penetration | invasion of earth and sand, muddy water, etc. can be prevented, the large sized double row tapered roller bearing 81 can be made long life. Therefore, a long life can also be realized for the rotary shaft support structure of a tunnel excavator provided with such a large double row tapered roller bearing 81.

  In addition, the seal that prevents intrusion of earth and sand etc. into the large double-row tapered roller bearing may be provided on the outside of the large double-row tapered roller bearing, or only on one of the left and right inner rings. It may be. Further, a plurality of seals may be arranged to prevent the intrusion of earth and sand etc. more efficiently.

  In the above embodiment, the large double-row tapered roller bearing is a large double-row tapered roller bearing configured so that the end surfaces on the small diameter side of the inner ring face each other. The structure which an end surface opposes may be sufficient, and two or more rows may be sufficient. Further, it may be a single row large tapered roller bearing.

  In the above embodiment, at room temperature, the circumferential dimension of the gap should be larger than 0.075% and smaller than 0.12% of the circumference of the circle passing through the center of the cage segment. However, it may be larger than 0.075% and smaller than 0.09% of the circumference of a circle passing through the center of the cage segment. By doing so, the safety factor of the cage can be set to 5.0 or more, so that deformation due to a collision can be further reduced.

In the above embodiment, the material of the outer ring and the inner ring is case-hardened steel. However, the invention is not limited to this. For example, a bearing steel having a thermal linear expansion coefficient of 1.25 × 10 ⁻⁵ / ° C. Selected.

  In the above embodiment, the outer diameter of the outer ring is 2500 mm and the inner diameter of the inner ring is 2000 mm. However, the outer diameter is not limited to this, and the inner diameter of the inner ring is 1000 mm or more. It is applied also to the large roller bearing which is 750 mm or more. For example, as a large roller bearing that is actually used in the above-described application, an outer ring having an outer diameter of 5000 mm or less and an inner ring having an inner diameter of 4500 mm or less is applied.

  In the above embodiment, the tapered roller is used as the roller accommodated in the cage segment. However, the present invention is not limited to this, and a cylindrical roller, a needle roller, a rod roller, or the like may be used.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  The large roller bearing according to the present invention is effectively used for a main shaft support structure of a wind power generator and a rotating shaft support structure of a tunnel excavator, which are required to prevent deterioration in function.

  In addition, the main shaft support structure for a wind power generator according to the present invention can be used effectively when it is required to prevent the function from being deteriorated.

  Moreover, the rotating shaft support structure for a tunnel excavator according to the present invention can be effectively used when it is required to prevent the function from being lowered.

It is an expanded sectional view showing the crevice between the first cage segment and the last cage segment among the large tapered roller bearings concerning one embodiment of this invention. It is a perspective view of a cage segment included in a large tapered roller bearing according to an embodiment of the present invention. It is sectional drawing at the time of cut | disconnecting the holder | retainer segment shown in FIG. 2 by the plane orthogonal to the rotating shaft line of a bearing including line III-III in FIG. It is sectional drawing at the time of cut | disconnecting the holder | retainer segment shown in FIG. It is a schematic sectional drawing of the large tapered roller bearing at the time of arrange | positioning a several retainer segment to the circumferential direction. It is an expanded sectional view which shows the adjacent retainer segment. It is a graph which shows the relationship between a cage | basket safety factor and the clearance of the circumferential direction. It is a figure which shows an example of the spindle support structure of the wind power generator using the large-sized tapered roller bearing which concerns on this invention. FIG. 9 is a schematic side view of the main shaft support structure of the wind power generator shown in FIG. It is a figure which shows an example of the rotating shaft support structure of the tunnel excavator which concerns on this invention. It is sectional drawing which shows a part of large sized double row tapered roller bearing contained in the rotating shaft support structure of the tunnel excavator shown in FIG. It is a perspective view of the retainer segment in the past. It is sectional drawing at the time of cut | disconnecting a part of tapered roller bearing provided with the retainer segment shown in FIG. 12 by the plane orthogonal to the rolling axis line of a bearing. It is a schematic sectional drawing at the time of cut | disconnecting the tapered roller bearing provided with the holder | retainer segment shown in FIG. 12 by the plane orthogonal to the rolling axis line of a bearing.

Explanation of symbols

  11a, 11b, 11c, 11d, 85a, 85b Cage segment, 12a, 12b, 12c, 34, 84a, 84b Tapered roller, 13a, 13b, 13c Pocket, 14a, 14b, 14c, 14d Pillar part, 15a, 15b 17a, 17b, 17c, 17d, 18b, 18c Guide claw, 21a, 21b, 21c, 21d, 21e, 21f End face, 22 PCD, 31 Large tapered roller bearing, 32, 82 Outer ring, 33, 83a, 83b Inner ring, 39 clearance, 50 support base, 51 swivel bearing, 52 nacelle, 53 casing, 54 bearing housing, 55 spindle support bearing, 56 spindle, 57 blade, 58 speed increaser, 59 generator, 60 motor for rotation, 61 speed reducer , 71 Rotating shaft support structure for tunnel excavator, 72 cutters, 73 units Turn head, 74 rotating shaft, 75 cutter head support, 76 motor, 77 fixing member, 78 ring member, 81 large double row tapered roller bearing, 86 inner ring spacer, 87 large flange, 88 outer diameter surface, 89 one end, 90 inner diameter surface, 91 seal, 92 cored bar part, 93 rubber part, 94 spring, 95 lip part.

Claims (11)

An outer ring, an inner ring, a plurality of rollers disposed between the outer ring and the inner ring, and a plurality of pockets that accommodate the rollers, and that are sequentially arranged in the circumferential direction between the outer ring and the inner ring. A large roller bearing comprising a cage segment of
The outer diameter of the outer ring is 1000 mm or more,
The inner diameter of the inner ring is 750 mm or more,
The linear expansion coefficient due to heat of the outer ring and the inner ring is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less,
The cage segment is made of a resin including a filler that reduces the coefficient of thermal expansion due to heat, and the coefficient of linear expansion due to heat is 1 × 10 ⁻⁵ / ° C. or more and 3 × 10 ⁻⁵ / ° C. or less. ,
When a plurality of the cage segments are arranged without gaps in the circumferential direction, a gap is provided between the cage segment first arranged and the cage segment arranged last,
A large roller bearing wherein the circumferential dimension of the gap is greater than 0.075% and less than 0.12% of the circumference of a circle passing through the center of the cage segment at room temperature. The large roller bearing according to claim 1, wherein the filler includes at least one of carbon fiber, glass fiber, graphite, carbon black, aluminum powder, iron powder, and molybdenum disulfide. The resin includes polyamide (PA), polyacetal (POM), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), syndiotactic polystyrene (SPS), polyphenylene sulfide (PPS), polyether ether ketone (PEEK), Liquid crystal polymer (LCP), fluororesin, polyether nitrile (PEN), polycarbonate (PC), modified polyphenylene ether (mPPO), polysulfone (PSF), polyethersulfone (PES), polyarylate (PAR), polyamideimide ( The large roller bearing according to claim 1 or 2, comprising at least one of the group consisting of PAI), polyetherimide (PEI), and thermoplastic polyimide (PI). The large roller bearing according to any one of claims 1 to 3, wherein a filling ratio of the filler in the resin is 20 wt% or more and 40 wt% or less. At room temperature, the circumferential dimension of the gap is greater than 0.075% and less than 0.09% of the circumference of a circle passing through the center of the cage segment. Large roller bearing as described. The large roller bearing according to any one of claims 1 to 5, wherein the roller is a tapered roller. The large roller bearing according to any one of claims 1 to 6, which supports a main shaft of a wind power generator that rotates together with a blade that receives wind power. The large roller bearing according to any one of claims 1 to 6, wherein a cutter head provided with a cutter for excavating earth and sand supports a rotating shaft provided at one end. The large roller bearing according to claim 8, wherein a seal is provided between the outer ring and the inner ring to prevent foreign matter from entering the bearing. A blade that receives wind,
One end of which is fixed to the blade and rotates with the blade;
A main shaft support structure of a wind power generator including a large roller bearing incorporated in a fixed member and rotatably supporting the main shaft,
The large roller bearing has an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a pocket for accommodating the rollers, and sequentially in the circumferential direction between the outer ring and the inner ring. A plurality of cage segments arranged in series,
The linear expansion coefficient due to heat of the outer ring and the inner ring is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less.
The cage segment is made of a resin including a filler that reduces the coefficient of thermal expansion due to heat, and the coefficient of linear expansion due to heat is 1 × 10 ⁻⁵ / ° C. or more and 3 × 10 ⁻⁵ / ° C. or less. ,
When a plurality of the cage segments are arranged without gaps in the circumferential direction, a gap is provided between the cage segment first arranged and the cage segment arranged last,
A wind turbine main shaft support structure, wherein a circumferential dimension of the gap is greater than 0.075% and less than 0.12% of a circumference of a circle passing through a center of the cage segment at room temperature. A cutter head equipped with a cutter for excavating earth and sand;
The cutter head is provided at one end, and a rotating shaft that rotates together with the cutter head;
A rotary shaft support structure for a tunnel excavator including a large roller bearing incorporated in a fixed member and rotatably supporting the rotary shaft,
The large roller bearing has an outer ring, an inner ring, a plurality of rollers arranged between the outer ring and the inner ring, and a pocket for accommodating the rollers, and sequentially in the circumferential direction between the outer ring and the inner ring. A plurality of cage segments arranged in series,
The linear expansion coefficient due to heat of the outer ring and the inner ring is 1 × 10 ⁻⁵ / ° C. or more and 2 × 10 ⁻⁵ / ° C. or less.
The cage segment is made of a resin including a filler that reduces the coefficient of thermal expansion due to heat, and the coefficient of linear expansion due to heat is 1 × 10 ⁻⁵ / ° C. or more and 3 × 10 ⁻⁵ / ° C. or less. ,
When a plurality of the cage segments are arranged without gaps in the circumferential direction, a gap is provided between the cage segment first arranged and the cage segment arranged last,
The rotating shaft support structure for a tunnel excavator, wherein the circumferential dimension of the gap is greater than 0.075% and less than 0.12% of the circumference of a circle passing through the center of the cage segment at room temperature.

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