JPH10252748A - Revolving seat bearing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a revolution seat bearing capable of guiding smooth revolution stability for a long period without the occurrence of damage due to reduction of a load from a roller. SOLUTION: A revolution seat bearing is formed such that a plurality of columnar rollers 4a are disposed between the outer ring groove part of the inner peripheral part of an annular outer ring part and an opposite inner ring groove part arranged on the outer peripheral surface of the annular ring part positioned on the inner peripheral side. A separator 31 consisting mainly of synthetic resin is located between rollers 4a such that the roller 4a is rotatable. A pair of rolling recessed parts 32 in which a part of the outer periphery of the roller 4a is inserted are arranged at the separator 31. The rolling recessed parts 32 and 32 comprise a first plane part 33 crossing orthogonally to the adjoining direction of the roller 4a and a pair of second plane parts 34 and 34 having an angle of 50-70 deg. with an adjoining direction. The roller 4a has an outer peripheral surface brought into contact with a first plane part 33 and a pair of second plane parts 34 and 34 and is disposed in a state to be supported in three spots. Stress is dispersed and a load is reduced, and stable and smooth revolution is assured for a long period without breakage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a swivel bearing having a separator interposed between rolling elements having a plurality of curved surfaces disposed between an outer ring portion and an inner ring portion.

[0002]

2. Description of the Related Art Conventionally, as a bearing for rotatably supporting a swinging working device such as a lifting machine such as a crane or a construction machine such as a hydraulic shovel, for example, a cross roller type swing provided with a single row double type thrust bearing. Seat bearings are known.

[0003] This swivel seat bearing is provided between an inner peripheral surface of an annular outer ring portion and an inner peripheral surface of an annular inner ring portion as shown in FIG.
A plurality of cylindrical rollers 51, which are rotatably held on the outer peripheral surface and are alternately arranged so that their axial directions are orthogonal to each other, and a separator 52 made of plastic or the like interposed between the rollers 51 and maintaining a distance are provided. ing.

[0004] The separator is formed of synthetic resin so that a rolling concave portion 53 having a concave curved surface with which the outer peripheral surface of a roller 51 whose axial direction intersects abuts opens in the opposite direction.

However, when the conventional separator shown in FIG. 7 is used, as shown in FIG. 7, only one point is brought into contact in plan view, and a large load is applied to the contacting point and the separator 52 Wear is easy to progress,
The smooth turning of the working device may be impaired.

Accordingly, as described in, for example, Japanese Utility Model Publication No. 46-12571 and Japanese Utility Model Application Laid-Open No. 63-152023, the rolling recess is formed in a substantially V-shaped cross section with the spherical rolling element facing the curved outer surface. A configuration is known in which the rolling element is formed in a planar shape that expands and receives rolling elements at two locations on the surface.

[0007]

However, Japanese Utility Model Publication No. 46-12571 and Japanese Utility Model Application Laid-open No. Sho 63-152 described above.
In the conventional configuration having the rolling recesses received at two places on the surface described in Japanese Patent No. 023, a tensile force is applied to a substantially central portion of the rolling recess between the positions where the rolling elements abut, and a large stress from the rolling elements is applied. When it is hung, there is a possibility that damage such as breakage such as tearing at the central portion of the rolling concave portion may occur.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a swivel seat bearing capable of reducing the load on a rolling element and achieving a smooth turn stably for a long time without breaking. And

[0009]

According to a first aspect of the present invention, there is provided a swivel bearing including an outer ring portion having a cylindrical inner peripheral surface and an inner peripheral surface of the outer ring portion located on the inner peripheral side of the outer ring portion. And a rolling element having a plurality of peripheral surfaces disposed between the outer ring section and the inner ring section, and a rolling element disposed between these adjacent rolling elements so that these rolling elements can roll. An elastically deformable separator having a pair of rolling recesses each having a plurality of planes with which the peripheral surfaces of the rolling elements come into contact, and the rolling recesses allow the peripheral surfaces of the rolling elements to rotate. The first rolling contact is substantially perpendicular to the adjacent direction of the adjacent rolling element.
And a pair of second flat portions which are located on both sides of the first flat portion and whose plane direction intersects with the adjacent direction of the rolling element. A first plane substantially orthogonal to the adjacent direction of the rolling elements of the pair of rolling recesses so that the peripheral surface of the rolling elements can rotate between a plurality of rolling elements disposed between the outer ring portion and the inner ring portion. Portion, and a pair of second flat portions, which are located on both sides of the first flat portion and intersect with the adjacent direction of the rolling members and intersect with the second flat portion, interpose the separator therebetween. It is supported by the first flat portion and the pair of second flat portions, and the stress applied to the separator from the rolling elements is dispersed, the load is reduced, and smooth turning is stably obtained for a long period of time. Further, since a load is applied only to the pair of second flat portions, a large tensile stress acting on the central portion of the rolling concave portion is generated, and no damage such as breakage occurs. Furthermore, if the curvature of the peripheral surface of the rolling element, the first flat portion and the second
The separator is elastically deformed when a load is applied even if the rolling element does not contact the first flat portion and the pair of second flat portions in a no-load state due to an angular error in the flat direction of the flat portion. Thereby, a state in which the first flat portion and the pair of second flat portions are brought into contact with each other and supported at three locations is obtained, so that manufacturability is improved and yield is improved.

According to a second aspect of the present invention, in the slewing seat bearing according to the first aspect, an angle of the second flat portion with respect to the adjacent direction of the rolling element is not less than 50 ° and not more than 70 °. Since the angle of the second flat portion with respect to the adjacent direction of the rolling element is set to 50 ° or more and 70 ° or less, the first flat portion and the pair of second flat portions which are distorted by the stress from the rolling element. Is a position where the distortion of the entire separator is dispersed and averaged, and there is no damage such as breakage of the separator. If the angle of the second flat portion with respect to the adjacent direction of the rolling element is smaller than 50 °, the portion of the second flat portion that contacts the rolling element approaches the thinner edge side of the rolling recess, and the first flat portion becomes in contact with the first flat portion. The angle formed by the plane direction of the plane part and the second plane part becomes smaller,
The moment force that deforms the edge portion of the rolling concave portion toward the outside may cause damage such as breakage of the separator particularly between the first plane portion and the second plane portion. Further, the angle of the second flat portion with respect to the adjacent direction of the rolling elements is 7
When the angle is larger than 0 °, a portion where the rolling element of the second flat portion comes into contact with a portion where the rolling element of the first flat portion comes close to each other, and a state where the load is concentrated on the central portion of the rolling concave portion. As a result, the load is not satisfactorily distributed over the entire separator, and smooth turning may not be stably obtained for a long period of time. For this reason, the angle of the second plane portion with respect to the direction in which the rolling elements are adjacent to each other is set to 50 ° or more and 70 ° or less.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a swivel bearing according to the present invention will be described below with reference to the drawings.

2 and 3, reference numeral 1 denotes a swivel seat bearing. The swivel seat bearing 1 includes a working device (not shown) such as a lifting machine such as a crane or a construction machine such as a hydraulic shovel, such as a vehicle or a ship. The work device is rotatably mounted on the main body and is interposed between the work device and the main body so as to pivotally support the work device.

The swivel seat bearing 1 has a substantially annular outer ring portion 2 and a substantially annular outer ring portion 2 disposed on the inner peripheral side of the outer ring portion 2 such that the outer peripheral surface faces the inner peripheral surface of the outer ring portion 2. An annular inner ring 3,
Rollers 4a and 4b, which are a plurality of cylindrical rolling elements, sandwiched between the outer ring portion 2 and the inner ring portion 3 and rotatably connect and hold the outer ring portion 2 and the inner ring portion 3 relatively rotatably.

The outer race portion 2 is formed of, for example, a hard steel material and has an inner peripheral surface formed in a substantially annular shape having a cylindrical shape, and is inserted along an axial direction through which a mounting member such as a bolt (not shown) for mounting a working device is inserted. A plurality of holes 6 are provided. further,
On the inner peripheral surface of the outer ring portion 2, there is provided an outer ring groove portion 7 having a substantially V-shaped groove shape that expands toward the outer peripheral surface of the inner ring portion 3 along the circumferential direction substantially at the center.

The outer ring groove 7 is formed in a substantially V-shaped groove so as to expand inward at the first inclined surface 8 and the second inclined surface 9. The first inclined surface 8 and the second
The inclined surface 9 is formed such that the vertical line is inclined at a predetermined angle, for example, approximately 45 ° with respect to the axial direction which is the vertical direction.
In addition, between the first inclined surface 8 and the second inclined surface 9 of the outer race groove portion 7, an annular concave groove-shaped relief portion 10 is provided.

Further, a circular inlet 14 is formed in the outer ring portion 2 and penetrates from the outer peripheral surface to the inner peripheral surface.
There is provided a lid 15 which closes 14 and is fixed by a bolt or a knock pin (not shown). Furthermore, the outer ring 2
An annular outer ring seal member 16 which is in contact with one edge of the inner ring portion 3 is protruded from an inner peripheral surface of the inner ring portion 3.

On the other hand, the inner race part 3 is formed of, for example, a hard steel material in a substantially annular shape having a cylindrical outer peripheral surface, like the outer race part 2, and has an attachment member such as a bolt (not shown) attached to a main body of a vehicle or a ship. Insertion hole 20 along the axial direction to be inserted
Are provided. Further, on the outer peripheral surface of the inner ring portion 3, a substantially V-shaped groove-shaped inner ring groove portion which is opened toward the inner peripheral surface of the outer ring portion 2 facing the outer ring groove portion 7 of the outer ring portion 2 substantially in the center along the circumferential direction. 21 are provided.

The inner ring groove 21 is formed in a substantially V-shaped groove so as to expand outward on the third inclined surface 22 and the fourth inclined surface 23. The fourth inclined surface 23 is opposed to the first inclined surface 8 of the outer ring groove 7 in parallel with the first inclined surface 8, that is, a predetermined angle, for example, approximately 45 degrees with respect to the axial direction in which the vertical line is the vertical direction.
°. In addition, the third inclined surface 22
Opposes in parallel to the second inclined surface 9, that is, a predetermined angle, for example, approximately 45 ° with respect to the axial direction whose vertical line is the vertical direction.
It is formed to be inclined. Furthermore, the third of the inner ring groove portion 21
Between the inclined surface 22 and the fourth inclined surface 23, an annular groove-shaped relief portion 24 is provided like the outer ring groove portion 7.

On the outer peripheral surface of the inner ring portion 3, an annular inner ring seal member 28 which is in contact with one edge of the outer ring portion 2 is projected, and the rolling elements 4a and 4b are sealed with the outer ring seal member 16. It has become. Further, on an inner peripheral surface of the inner ring portion 3, a gear 29 meshed with a gear of driving means (not shown) provided in the working device is provided.
Are formed.

On the other hand, as shown in FIGS. 1 to 4, the rollers 4a and 4b are formed in a substantially columnar shape with a chamfered end edge made of, for example, a hard steel material similarly to the outer ring portion 2 and the inner ring portion 3. I have. The outer surfaces of the rollers 4a and 4b are the first of the outer ring grooves 7.
The state of the rotating shaft a contacting the inclined surface 8 of the inner ring groove 21 and the fourth inclined surface 23 of the inner ring groove 21 and the outer peripheral surface of the rotary shaft a The rotating shaft b is in contact with the rotating shaft a and the rotating shaft b alternately so that the rotating shaft a and the rotating shaft b are orthogonal to each other. The outer ring groove 7, the inner ring groove 21, and the rollers 4a, 4b constitute a single-row double-type thrust bearing 30.

The axial end faces of the rollers 4a and 4b are provided with a slight gap so that they do not come into contact with the outer ring groove 7 and the inner ring groove 21 under a load.

Also, between the rollers 4a, 4b, the distance between the rollers 4a, 4b is maintained, and the rollers 4a, 4b are held without looseness in the outer ring groove portion 7.
Further, a separator 31 which is a gap holding member formed of a reinforced plastic mixed with a synthetic resin such as 6-6 nylon or glass fiber or the like is provided between the inner ring grooves 21.

As shown in FIGS. 1 and 4, the separator 31 is formed of a plurality of planes such that a pair of opposing side surfaces of the rectangular parallelepiped run along the outer circumferences of the rollers 4a and 4b whose axial directions intersect. A pair of rolling recesses 32 are formed in the recessed shape. These rolling recesses 32, 32
Is a first plane portion 33 whose plane is orthogonal to the direction in which the rollers 4a and 4b are adjacent to each other at a substantially central portion, and the plane direction is located on both sides of the first plane portion 33 and the plane direction is adjacent to the rollers 4a and 4b. For the direction,
A pair of second plane portions 34, 34 having a predetermined angle, for example, 50 ° or more and 70 ° or less are provided. The rollers 4a, 4b are so arranged that the outer peripheral surfaces of the rollers 4a, 4b abut against the first flat portion 33 and the pair of second flat portions 34, 34 to support the rollers 4a, 4b at three places. Rollers 4a and 4b are rotatably disposed with a separator 31 interposed therebetween. In addition, the outer race 2 and the inner race 3 are relatively rotatably connected and held by the rollers 4a and 4b being disposed in a state of intersecting the axial direction with the separator 31 interposed therebetween.

The peripheral surface of the separator 31 does not come into contact with the first inclined surface 8, the second inclined surface 9, the third inclined surface 22, and the fourth inclined surface 23, but through a slight gap. They are opposed to each other.

Also, by driving the driving means of the working device,
The gear of the driving means meshing with the gear 29 of the inner race 3 is the inner race 3
The working device rotates together with the outer ring portion 2 with respect to the inner ring portion 3 attached and fixed to the main body, and turns.

Next, an operation of assembling the swivel seat bearing according to the embodiment will be described.

First, the inner ring portion 3 is positioned coaxially in advance on the inner peripheral side of the outer ring portion 2, and the roller is inserted through the inlet 14 of the outer ring portion 2.
4a, 4b and separator 31 are connected to outer ring groove 7 and inner ring groove.
Feed alternately between 21. When loading the rollers 4a, 4b and the separator, the rollers 4a, 4b are loaded so that the state of the rotating shaft a and the state of the rotating shaft b are alternately located. After the rollers 4a and 4b and the separator 31 are disposed in the outer ring groove 7 and the inner ring groove 21, the cover 15 is closed with a bolt or a knock pin (not shown) so as to close the input port 14.
And the revolving seat bearing 1 is assembled.

When the rollers 4a, 4b and the separator 31 are loaded from the loading port 14, the diagonal dimension T of the separator 31 is determined by the diameter of the rollers 4a, 4b, ie, the outer ring groove 7 and the inner ring groove 21 facing each other. Composed rollers 4a. The distance between the first inclined surface 8 and the fourth inclined surface 23, which is the width dimension of the tube-shaped portion where the 4b and the separator 31 are disposed, and the second inclined surface 9 and the third inclined surface It is designed to be longer than the distance facing 22. For this reason, when the separator 31 falls down in the tube-shaped portions opposed to each other by the outer ring groove 7 and the inner ring groove 21, the rollers 4 a,
It is possible to prevent the state where the 4b is inserted from being lost.

Next, the operation of the swivel bearing 1 according to the embodiment will be described.

A case in which a working device (not shown) such as a lifting machine such as a crane or a construction machine such as a hydraulic shovel is arranged so that the radial direction of the swivel bearing 1 is horizontal and pivotally mounted. explain.

The rollers 4a and 4b contact the separator 31 so as to bite into the separator 31 microscopically due to the load caused by the driving of the working device and the weight of the rollers. As shown in FIG. 1 and FIG. 5, the elastic deformation of the separators 31 into which the rollers 4a and 4b bite is caused by the first flat portions 33 and the second flat portions 34 and 34 of the rolling recesses 32 and 32.
Are generated as deformations δ along the contact direction of the rollers 4a, 4b at the positions where the rollers 4a, 4b abut.

From Hertz's theory, each deformation δ is converted into the first plane portion 33 and the second plane portions 34, 34.
Is approximately proportional to the force _{Pn in} the vertical direction of
The force P ₁ in the vertical direction on the flat portion 33 is as follows: P ₁ = δ sin θ = δ sin 90 ° = δ Therefore, the force P ₂ in the vertical direction in the second plane portion 34 becomes _{P 2 = δsinθ = P 1 sinθ} . Therefore, the rollers in the second flat portions 34, 34
The partial pressure P ₃ along the contact direction of 4a, 4b is P ₃ = (P ₁ sin θ) sin θ = P ₁ sin ² θ, and the sum of these becomes the stress P applied to the separator 31 from the rollers 4a, 4b. That is, P = P ₁ + 2P ₁ sin ² θ. When the force P ₁ in the vertical direction on the first plane portion 33 is represented by P, P ₁ = P / (1 + ² sin ² θ).

The rollers 4 in the second flat portions 34, 34
The partial pressure P ₄ orthogonal to the partial pressure P ₃ along the contact direction of a and 4b
Is: P ₄ = (P ₁ sin θ) cos θ = P ₁ sin θcos
θ.

Here, the plane direction of the second plane portion 34 is
When set at 70 ° with respect to the direction in which the rollers 4a and 4b are adjacent to each other, the force P ₁ in the vertical direction on the first flat portion 33 is P ₁ = P / (1 + ² sin ²⁾ θ) = P / (1 + ² sin ² 70 °) = 0.362P. Further, in the second planar portion 34, vertical force P _{2 is, P 2 = P 1 sinθ =} 0.362Psin70 ° = 0.340P roller 4a, the partial pressure P along the abutment direction of 4b ^{_{3, P 3 = P 1 sin 2}} θ = 0.362Psin 2 70 ° = 0.320P roller 4a, the partial pressure P ₄ that is orthogonal to the contact direction. _{4b, P 4 = P 1 sinθcosθ =} 0.362Psin70 ° cos70 ° = 0.116P.

On the other hand, the plane direction of the second plane portion 34 is
When the angle is set to 50 ° with respect to the adjacent direction of the rollers 4a and 4b, which are the contact directions of the rollers a and 4b, the force P ₁ in the vertical direction on the first flat portion 33 is P ₁ = P / (1 + ² sin ²⁾ θ) = P / (1 + ² sin ² 50 °) = 0.460P. Further, in the second planar portion 34, vertical force P _{2 is, P 2 = P 1 sinθ =} 0.460Psin50 ° = 0.352P roller 4a, the partial pressure P along the abutment direction of 4b ^{_{3, P 3 = P 1 sin 2}} θ = 0.460Psin 2 50 ° = 0.270P roller 4a, the partial pressure P ₄ that is orthogonal to the contact direction. _{4b, P 4 = P 1 sinθcosθ =} 0.460Psin50 ° cos50 ° = 0.227P.

For this reason, the stress applied to the separator 31 from the rollers 4a and 4b is divided into approximately three equal parts, the load is reduced at each contact point, and smooth turning is stably obtained for a long period of time.

When the plane direction of the second plane portions 34, 34 is smaller than 50 ° with respect to the direction adjacent to the rollers 4a, 4b, the second plane portions 34, 34 come into contact with the rollers 4a, 4b of the second plane portions 34, 34. The part approaches the thinner edge of the rolling recesses 32, 32,
The angle formed between the first plane portion 33 and the second plane portions 34, 34 in the plane direction becomes smaller, and the second angle from the boundary between the first plane portion 33 and the second plane portions 34, 34 The distance L to the portions of the flat portions 34, 34 that come into contact with the rollers 4a, 4b increases. Then, as described above, the roller 4a, the partial pressure P ₄ that is orthogonal to the contact direction of the 4b increases.

Therefore, the moment force tends to increase due to the vertical stress P ₂ of the second flat portion 34 received from the rollers 4 a and 4 b, and in particular, the first flat portion 33 and the second flat portion 3 are increased.
There is a possibility that damage such as breakage or breakage may occur, such as tearing at the boundary with 4, 34.

On the other hand, when the plane direction of the second plane portions 34, 34 is larger than 70 ° with respect to the direction adjacent to the rollers 4a, 4b, the rollers 4a, 4b of the second plane portions 34, 34 come into contact. The portion and the portion of the first flat portion 33 where the rollers 4a and 4b are in contact with each other are close to each other, and are in a state similar to the case where the roller comes into contact with the roller at one place in the related art. do it,
There is a possibility that the load cannot be satisfactorily distributed over the entire separator 31 and smooth turning cannot be stably obtained for a long period of time. For this reason, it is preferable that the angle of the second plane portions 34, 34 with respect to the adjacent direction of the rollers 4a, 4b is set to 50 ° or more and 70 ° or less.

By the way, an error occurs in the diameter dimension of the rollers 4a, 4b, and an error occurs in the width dimension of the first flat portion 33 and the second flat portion 34, 34 and the angle formed by the flat direction.
Even if the outer peripheral surfaces of the rollers 4a and 4b abut on only the first flat portion 33 and one of the second flat portions 34 or only on the pair of second flat portions 34 and 34, the synthetic resin can be used. The separator 31 formed so as to be elastically deformable as a base material includes rollers 4a, 4b
Due to the stress received by the first flat portion 33 or the second flat portion 34 with which the rolling concave portions 32 abut, the rolling concave portions 32 are slightly deformed so as to spread or narrow. Due to this deformation, the other first flat portion 33 or the second flat portion 34 comes into contact with the outer peripheral surfaces of the rollers 4a and 4b, and a state of being supported at predetermined three locations is obtained.

As described above, the outer ring portion 2 and the inner ring portion 3
The curved surfaces of the rollers 4a and 4b are rotatable between the rollers 4a and 4b disposed between the rollers 4a and 4b. The separator 31 is brought into contact with the first flat portion 33 and a pair of second flat portions 34, 34 located on both sides of the first flat portion 33 and intersecting at an acute angle with respect to the adjacent direction of the rollers 4a, 4b. Rollers 4a, 4b
Is supported by the first flat portion 33 and the pair of second flat portions 34, 34, the stress applied from the rollers 4a, 4b to the separator 31 is dispersed, the load is reduced, and smooth turning is stable for a long time. Is obtained.

Further, the rollers 4a, 4a,
In the case of supporting 4b, the ratio of the load to the stress received on one surface increases, so that the service life of the separator 31 cannot be further improved. The separator 31 may be damaged when a large stress is applied, such as breakage. However, according to the above-described embodiment, since the rollers 4a and 4b are supported at three locations, the stress received at one location may be increased. And the life of the separator 31 can be increased by reducing the damage such as abrasion of the separator 31, and a stable turning can be obtained for a long period of time. The tearing stress acting on the central portion of each of the 32, 32, particularly the boundary between the two first flat portions 33 and the second flat portions 34, 34 can be greatly reduced, and the separator can be greatly reduced.
No damage such as breakage or breakage of 31 occurs.

Further, even if the outer peripheral surfaces of the rollers 4a and 4b do not come into contact with each other due to a dimensional error of each portion, the first separator 31 is elastically deformed when a load is applied, thereby causing the first.
A state where the flat portion 33 and the pair of second flat portions 34, 34 are brought into contact with each other and supported at three places is obtained, errors can be tolerated, manufacturability can be improved, yield can be improved, and cost can be reduced.

Further, since the angle of the second plane portions 34, 34 with respect to the adjacent direction of the rollers 4a, 4b is set to be not less than 50 ° and not more than 70 °, the first strain which is generated by the stress from the rollers 4a, 4b.
And the rollers 4a of the pair of second flat portions 34, 34
The part in contact with 4b is not too close, and the distortion is
Since the entirety of 31 is dispersed and averaged, the rollers 4a and 4b can rotate smoothly, a stable rotation can be obtained, and damage such as breakage of the separator 31 can be prevented.

In the above-described embodiment, the structure in which the cylindrical rollers 4a and 4b are alternately arranged as the rolling elements so as to intersect in the axial direction has been described. Any shape such as a spherical shape having a curved surface, a conical shape, and a barrel shape may be used, and the same effect can be obtained even if the axial directions do not intersect.

Although the outer ring portion 2 and the inner ring portion 3 are formed in a substantially annular shape, the configuration of the outer peripheral side of the outer ring portion 2 and the inner peripheral side of the inner ring portion 3 are appropriately set according to the use mode.

Further, the first flat portion 33 and the second flat portion 33
Although described as being adjacent to the first flat portion 33, the first flat portion 33 and the second flat portion 34 may be adjacent to each other via a curved surface in an arc shape. According to this configuration, the tearing load acting on the boundary portion between the first plane portion 33 and the second plane portion 34 is dispersed, and the breakage that tears at the boundary portion even when a large stress is applied is reliably prevented. it can.

Further, the arrangement of the rollers 4a and 4b is not limited to the case where the rollers 4a and 4b are inserted from the insertion port 14 closed by the lid 15, and for example, as shown in FIG. The outer ring part 42 is divided into two parts, and the first outer ring part 43 is divided into two parts.
Either configuration may be adopted, such as disposing the rollers 4a and 4b while aligning the second outer ring portion 44 with the second outer ring portion 44.

[0049]

According to the turning seat bearing according to the first aspect, the first flat portion which is substantially perpendicular to the adjacent direction of the rolling elements of the pair of rolling recesses, and both sides of the first flat portion are provided. The first flat portion and the pair of second flat portions are disposed so as to be in contact with a pair of second flat portions which are located and whose plane directions intersect with the adjacent direction of the rolling elements and the separator is interposed between the rolling elements. The stress applied to the separator from the rolling elements supported by the bearings is dispersed and the load is reduced, large tensile stress is not generated at the center of the rolling recess, damage such as breakage can be prevented, and elastic deformation of the separator ensures The rolling element can be supported at three places by contacting the first flat portion and the pair of second flat portions, and smooth turning can be obtained stably for a long period of time, and the allowable amount of dimensional error increases. In addition, manufacturability and yield can be improved, and costs can be reduced.

According to the second aspect of the present invention, in addition to the effect of the first aspect, the angle of the second flat portion with respect to the adjacent direction of the rolling element is set to 50 ° or more and 70 ° or less. The portions of the first flat portion and the pair of second flat portions which are distorted by the stress from the rolling elements and which come into contact with the rolling elements have a positional relationship in which the entirety of the separator is dispersed and averaged. Can be prevented, and stable turning can be obtained for a long period of time.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing a relationship between a roller and a separator showing an embodiment of a swivel seat bearing of the present invention.

FIG. 2 is a partially cut-away sectional view showing the same swivel seat bearing.

FIG. 3 is a cross-sectional view showing the same swivel seat bearing.

FIG. 4 is a perspective view showing an arrangement state of the roller and the separator.

FIG. 5 is an explanatory diagram showing a state of a force applied to the separator.

FIG. 6 is a partially cutaway sectional view showing another embodiment of the swivel bearing of the present invention.

FIG. 7 is an explanatory view showing a relationship between a roller and a separator of a conventional swivel seat bearing.

[Explanation of symbols]

 1,41 Swing seat bearing 2,42 Outer ring part 3 Inner ring part 4a, 4b Roller as rolling element 32 Rolling concave part 33 First plane part 34 Second plane part

Claims (2)

[Claims] 1. An outer ring portion having an inner peripheral surface having a cylindrical shape, an inner ring portion located on the inner peripheral side of the outer ring portion and having an outer peripheral surface facing the inner peripheral surface of the outer ring portion with a small diameter; A rolling element having a plurality of peripheral surfaces disposed between the inner ring portions; and a plurality of planes disposed between these adjacent rolling elements and contacting the peripheral surfaces of the rolling elements so that these rolling elements can roll. An elastically deformable separator having a pair of rolling recesses having the rolling recess, wherein the circumferential surface of the rolling element abuts rotatably, and the planar direction is in the adjacent direction of the adjacent rolling element. And a pair of second flat portions located on both sides of the first flat portion and intersecting the direction of the rolling element adjacent to the rolling element. And swivel bearing. 2. The swivel bearing according to claim 1, wherein the angle of the second flat portion with respect to the adjacent direction of the rolling elements is not less than 50 ° and not more than 70 °.