Self-aligning roller bearing

Abstract

Provided is a self-aligning roller bearing which has sufficient strength, is capable of suppressing the operation of rollers, is easy to process, can be manufactured at low cost, and is provided with a comb-shaped punched retainer. A self-aligning roller bearing (1) is provided with an outer ring (2), an inner ring (3), a plurality of rollers (4) arranged in two rows in a ring shape between the outer ring (2) and the inner ring (3), and a cut cage (5) for holding the plurality of rollers (4), the cut cage (5) being provided with a ring-shaped portion (5a) arranged between the two rows of rollers, and a plurality of column portions (5b) protruding from axial side surfaces on both sides of the ring-shaped portion (5a). Pockets (P) for holding the rollers in a rollable manner are formed by circumferentially adjacent columns (5b) of the plurality of columns (5b), and each pocket (P) has a pocket bottom portion which is continuous with the annular portion and is located on the root side of the corresponding column, and a pocket inlet portion which extends from the axial front end edge of the pocket bottom portion to the front end of the corresponding column. The pocket bottom portion is a partial conical surface whose diameter decreases from the axial front end edge toward the root side of the column portion, and the pocket inlet portion is a partial cylindrical surface.

Description

Technical Field

[0001] The invention relates to a self-aligning roller bearing. Background Art

[0002] In a self-aligning roller bearing, a cage having a comb-shaped or cage-shaped shape is used as a cage for holding the rollers, and cages of various shapes have been proposed (Patent Documents 1 and 2).

[0003] The roller bearing retainer shown in Patent Document 1 is a comb-shaped retainer composed of an annular portion and a plurality of columnar portions protruding from the annular portion, and the roller is retained in a pocket formed by the columnar portions adjacent to each other in the circumferential direction. Fig. 8A , Figure 8B and Figure 8C As shown, the pocket portion is formed by processing the side surface 104d of the column portion 104b into a concave partial cylindrical surface, and the inner surface shape of the pocket portion p is cylindrical to the root of the column portion 104b.

[0004] The self-aligning roller bearing shown in Patent Document 2 has spherical rollers as rolling elements. Fig.9A and Fig. 9B As shown in FIG. 1 , the inner surface shape of the pocket p for retaining the spherical roller in the cage 214 is set to a concave shape along the rolling surface of the spherical roller.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] [Patent Document 1]: Japanese Patent Publication No. 2008-069868

[0008] [Patent Document 2]: Japanese Patent Publication No. 2018-169044 Summary of the invention

[0009] [Problems to be solved by the invention]

[0010] However, in the comb-shaped retainer, if the side shapes 104d, 214c, and 214d of the circumferentially adjacent pillars 104b and 214b forming each pocket are set to be cylindrical shapes that are concave from the front end of the pillar to the root, the cross-sectional area (hereinafter sometimes simply referred to as "cross-sectional area") along the circumferential direction of the root 113 and 214d becomes small, so that sufficient strength of the pillar cannot be ensured. In addition, since the gap between the rollers retained in the pockets p and P and the pillars 104b and 214b becomes large, there is a problem that the movement of the rollers cannot be fully suppressed, and the position and posture of the rollers are unstable.

[0011] In addition, if the inner surface shape of the pockets p and P that retain the rollers is set to a concave shape along the outer diameter surface of the spherical roller, the cross-sectional area of ​​the root 113 and 214d of the column 104b and 214b of the retainer 104 and 214 becomes larger, which can improve the strength. At the same time, since the gap between the column 104b and 214b and the roller becomes uniform along the axial direction of the pocket, the movement of the roller can be suppressed. However, if such a structure is adopted, it is necessary to set the shape of the drill for machining the pockets p and P to a spherical shape along the outer diameter of the roller. Therefore, there is a problem that the molding of the tool takes time and effort, and the manufacturing cost of the retainer becomes high.

[0012] An object of the present invention is to provide a self-aligning roller bearing capable of suppressing the movement of rollers while ensuring the strength of a retainer column and achieving a reduction in manufacturing cost.

[0013] [Technical solution to the problem]

[0014] In order to solve the above-mentioned problems, the self-aligning roller bearing of the present invention comprises an outer ring, an inner ring, a plurality of rollers arranged in two rows of rings between the outer ring and the inner ring, and a cut retainer for holding the plurality of rollers. The cut retainer is a comb-shaped cut retainer, which includes an annular portion arranged between the two rows of rollers and a plurality of column portions protruding from the axial side surfaces on both sides of the annular portion. Pockets for holding each roller freely in a rolling manner are formed by the column portions adjacent to each other in the circumferential direction of the plurality of column portions. The pocket has a pocket bottom connected to the annular portion and located on the root side of the column portion, and a pocket entrance portion extending from the axial front end edge of the pocket bottom to the front end of the column portion, the pocket bottom is a partial conical shape whose diameter decreases as it moves from the axial front end edge toward the root side of the column portion, and the pocket entrance portion is a partial cylindrical shape.

[0015] With this structure, since the cross-sectional area of ​​the root of the column of the retainer can be made larger than the cross-sectional area of ​​the front end of the column, the strength of the retainer can be improved compared with the retainer of the existing structure in which the cross-sectional area of ​​the root of the column is reduced. Furthermore, in the case of deflection of the roller, since the root of the column of the retainer contacts the outer diameter of the roller, the movement of the roller can be suppressed. In addition, since the shape of the pocket is a simple shape without an R shape, it is relatively easy to shape the drill used for processing the pocket, so the retainer can be manufactured inexpensively.

[0016] In the self-aligning roller bearing of the present invention, the axial length of the bottom of the pocket may be 20-40% of the axial length of the roller.

[0017] With this structure, when the bearing rotates, the root of the column portion of the retainer forming the bottom of the pocket does not contact the maximum diameter portion of the roller, and no force is generated to tilt the rotation axis of the retainer relative to the retainer. Therefore, the positional relationship between the retainer and the roller can be well maintained, and the movement of the roller can be suppressed. If the axial length of the bottom of the pocket exceeds 40% of the axial length of the roller, the maximum diameter portion of the roller contacts the local conical surface during the rotation of the bearing, and there is a possibility that a force is applied to tilt the rotation axis of the retainer. If the axial length of the bottom of the pocket is less than 20% of the axial length of the roller, the cross-sectional area of ​​the root of the column portion may not be fully ensured, which may cause problems in strength.

[0018] In the self-aligning roller bearing of the present invention, the inclination angle of the local conical surface can be the angle of the rolling surface of the roller at the following position relative to the tangent direction of the roller axis, which is an axial position from the axial base end edge of the bottom of the pocket to 10 to 30% of the axial length of the roller.

[0019] With this structure, since the roller contacts the root of the column of the retainer at an appropriate tilt angle when contacting, the movement of the roller can be fully controlled, and the root of the column of the retainer is difficult to contact the edge between the outer diameter surface of the roller and the chamfer on the end face side, so the wear of the root of the column of the retainer can be reduced. If it exceeds 30% of the axial length of the above-mentioned roller, the deflection angle when the roller contacts the local conical surface becomes undesirably large, so the effect of controlling the movement of the roller is reduced. If it is less than 10% of the axial length of the roller, the edge between the outer diameter surface of the roller and the chamfer on the end face side is easy to contact, and there is a concern about the wear of the local conical surface.

[0020] The present invention includes any combination of at least two structures disclosed in the claims and / or the specification and / or the drawings.

[0021] In particular, any combination of claims is included in the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The present invention will be more easily understood through the following description of preferred embodiments with reference to the accompanying drawings.

[0023] However, the embodiments and drawings are for illustration and description only and should not be used to limit the scope of the present invention.

[0024] The scope of the present invention is defined by the claims.

[0025] In the drawings, the same reference numerals in a plurality of drawings represent the same or corresponding parts.

[0026] Figure 1 It is a longitudinal sectional view of the self-aligning roller bearing according to the first embodiment of the present invention.

[0027] Figure 2 is along Figure 1 Cross-sectional view along line II-II.

[0028] Figure 3 2 is a cross-sectional view of the main part of the self-aligning roller bearing according to the second embodiment of the present invention (with Figure 2 equivalent figure).

[0029] Figure 4 It is a cross-sectional view of a main part of a self-aligning roller bearing according to a third embodiment of the present invention.

[0030] Figure 5 It is a longitudinal sectional view of a self-aligning roller bearing according to a fourth embodiment of the present invention.

[0031] Figure 6 It is a longitudinal sectional view of a self-aligning roller bearing according to a fifth embodiment of the present invention.

[0032] Figure 7 yes Figure 6 VII-VII line cross-sectional view.

[0033] Fig. 8A It is an enlarged front view of the main parts showing an example of a conventional roller bearing cage.

[0034] Figure 8B It is an enlarged plan view of a main part showing an example of a conventional roller bearing cage.

[0035] Figure 8C This is a left side view of the main parts showing an example of a conventional roller bearing cage.

[0036] Fig.9A It is a plan view showing an example of a conventional cage for a self-aligning roller bearing.

[0037] Fig. 9B yes Fig.9A BB cross-section diagram. DETAILED DESCRIPTION

[0038] [First embodiment]

[0039] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 and Figure 2 1 is a diagram showing a first embodiment of the self-aligning roller bearing of the present invention. Figure 1As shown, the self-aligning roller bearing 1 includes an outer ring 2, an inner ring 3, a plurality of rollers 4, and a retainer 5. The plurality of rollers 4 are arranged in two rows between the inner ring 3 and the outer ring 2, and the retainer 5 retains the two rows of rollers 4, 4. The bearing space between the inner ring 3 and the outer ring 2 is filled with, for example, grease. In this specification, the self-aligning roller bearing 1 is sometimes simply referred to as a "bearing".

[0040] A concave spherical raceway surface 2a is formed on the inner diameter surface of the outer ring 2, and two rows of concave spherical raceway surfaces 3a, 3a are formed on the outer diameter surface of the inner ring 3. Flange portions 6, 6 bulging outwardly are provided on the axially outer side of the inner ring 3. Two rows of rollers 4, 4 are provided between the raceway surface 2a of the outer ring 2 and the raceway surfaces 3a, 3a of the inner ring 3. The rollers 4 of each row are so-called barrel rollers whose rolling surfaces are spherically expanded. The subassembly including the inner ring 3, the retainer 5 and the two rows of rollers 4, 4 is configured to be relatively alignable with respect to the outer ring 2. The self-aligning roller bearing 1 is one of the so-called radial roller bearings in which the outer ring 2 is arranged radially outside the outer peripheral surface of the inner ring 3. The axial direction of the central axis of the inner ring 3 and the outer ring 2 is set as the "axial direction". The direction orthogonal to the above-mentioned "axial direction" is set as the "radial direction".

[0041] <Retainer>

[0042] like Figure 2 As shown, the retainer 5 is a comb-shaped retainer including an annular portion 5a and columnar portions 5b protruding axially outward from both sides of the annular portion 5a. The columnar portions 5b, 5b adjacent to each other in the circumferential direction form pockets P for retaining the rollers 4. The pockets P are arranged in two rows on the left and right sides of the annular portion 5a in a circumferentially evenly distributed manner, and each pocket P retains a plurality of rollers 4 in two rows. The pockets P in each row can also be formed differently from each other by staggering the circumferential phase of the columnar portions 5b of the retainer 5 on both sides protruding from the annular portion 5a. By such an arrangement, it is possible to prevent the concentration of load at the same phase position in the circumferential direction of the annular portion 5a.

[0043] like Figure 1 As shown in FIG. 1 , the outer diameter surface 5bc of the column portion 5b may be a shape whose outer diameter decreases toward the outer side in the rotation axis direction of the retainer 5. With this structure, since the roller can be guided approximately along the radial middle between the outer diameter surface 5bc of the column portion 5b and the inner diameter surface 5bd formed by the annular surface, the force acting on the column portion 5b due to contact with the roller 4 can be received near the radial center of the column portion 5b. As a result, the rigidity of the column portion 5b is improved.

[0044] like Figure 1As shown, the column portion 5b of the retainer 5 may have a length exceeding 50% of the axial length of the roller 4. Thus, when the roller 4 is retained in the pocket P, since the front end of the column portion 5b of the retainer 5 extends to a position axially outward of the maximum diameter position of the roller 4, the roller 4 is retained across the maximum diameter of the roller 4, and the roller 4 can be retained more stably.

[0045] like Figure 2 As shown, the cage 5 is a cut cage in which each pocket P is formed by cutting with a drill, and is a rolling element guided cage guided by a plurality of rollers 4. The cage 5 is made of an iron-based material, a brass-based material, or a resin-based material.

[0046] <Pocket shape>

[0047] The pocket P has a pocket bottom Pb connected to the annular portion 5a and located on the root side of the column portion 5b, and a pocket entrance Pa extending from the axial front end edge 7 of the pocket bottom Pb to the front end of the column portion 5b. The pocket entrance Pa is a partial cylindrical surface, and the pocket bottom Pb is a partial conical surface whose diameter decreases as it moves from the axial front end edge 7 toward the root side of the column portion 5b. Since the pocket P is formed by adjacent column portions 5b, 5b, the circumferential side surface of the column portion 5b has a shape corresponding to the pocket P. When the pocket P has the above shape, the circumferential side surface of the front end portion 5ba of the column portion 5b corresponding to the entrance of the pocket P is a concave partial cylindrical surface. The circumferential side surface of the root portion 5bb of the column portion 5b corresponding to the bottom of the pocket P is a concave partial conical surface.

[0048] <Effects>

[0049] According to the above description Figure 1 and Figure 2In the self-aligning roller bearing shown in the figure, the comb-cut retainer 5 provided in the self-aligning roller bearing 1 includes an annular portion 5a disposed between the rows of rollers 4, 4 in the two rows and a plurality of columnar portions 5b protruding from the axial side surfaces on both sides of the annular portion. The columnar portions 5b, 5b adjacent to each other in the circumferential direction of the plurality of columnar portions 5b form a pocket P as a space for freely rolling retaining each roller 4. The pocket P includes a pocket bottom Pb connected to the annular portion 5a and located on the root side of the columnar portion 5b, and a pocket entrance Pa extending from the axial front end edge 7 of the pocket bottom Pb to the front end of the columnar portion 5b, and the pocket bottom Pb is a partial conical surface whose diameter decreases as it moves from the axial front end edge 7 toward the root side of the columnar portion 5b. As a result, the cross-sectional area of ​​the root of the columnar portion 5b of the retainer 5 is made larger than the cross-sectional area of ​​the front end of the columnar portion 5b, and the movement of the roller 4 can be suppressed while the strength of the columnar portion 5b is sufficiently ensured. Furthermore, since the shape of the pocket P for holding the roller 4 in the retainer 5 is a simple shape that is easier to process than a spherical shape, the shape of the drill used for cutting the retainer 5 is a relatively easy shape, and the retainer can be manufactured at a lower cost.

[0050] <About other implementation forms>

[0051] [Second embodiment]

[0052] Figure 3 A second embodiment of the present invention is shown. Figure 3 The comb-shaped cut retainer of the self-aligning roller bearing of the present invention is Figure 2 Corresponding cross-sectional view In this embodiment, the axial length L1 of the pocket bottom Pb is in the range of 20% to 40% of the roller length L of the roller 4 held in the pocket P.

[0053] The strength of the column 5b protruding from the annular portion 5a in the retainer 5 is related to the axial length L1 of the pocket bottom Pb having a partial conical surface in the pocket P. The longer the axial length L1 of the pocket bottom Pb, the thicker the wall of the column 5b of the retainer 5 in the circumferential direction, so the rigidity increases, and the cross-sectional area of ​​the root of the column 5b connected to the annular portion 5a increases, so the strength of the column 5b increases. On the other hand, when the axial length L1 of the pocket bottom Pb is close to 50% relative to the roller length L of the roller retained in the pocket P, the maximum diameter portion of the roller 4 contacts the column 5b of the retainer 5 during the rotation of the bearing. In this case, since a force in a direction that tilts the rotation axis of the retainer 5 is applied, the movement of the roller 4 in the pocket P cannot be fully suppressed, and the strength of the column 5b is reduced.

[0054] The relationship between the axial length L1 of the bottom Pb having a partial conical surface in the pocket P and the strength of the column portion was studied, and the results in Table 1 were obtained. The value in the "Pocket Bottom Length" column in the table represents the ratio of the axial length L1 of the pocket bottom Pb to the length L of the retained roller. In the column strength column in the table, the symbol "0" indicates that the column portion of the retainer has sufficient strength, the symbol "△" indicates that the column portion of the retainer has no problem in strength, and the symbol "×" indicates that the column portion of the retainer has a problem in strength.

[0055] [Table 1]

[0056] Pocket bottom length 0％ 10％ 20％ 30％ 40％ 50％ Column strength × △ 〇 〇 〇 △

[0057] In consideration of the above, it is determined that in the comb-shaped cut retainer of the self-aligning roller bearing of the present invention, the axial length L1 of the bottom of the pocket P is preferably in the range of 20% to 40% of the length L of the roller 4 retained in the pocket P. In this way, by setting the axial length L1 of the pocket bottom Pb having a partial conical surface in the pocket P of the retainer 5 to be within an appropriate numerical range, the strength of the column portion 5b of the retainer 5 can be ensured, and the movement of the roller 4 retained in the pocket P of the retainer 5 can be sufficiently suppressed.

[0058] [Third embodiment] (Technical solution 3 / Figure 4 Implementation form)

[0059] Figure 4 The third embodiment of the present invention is shown. In the self-aligning roller bearing of the present invention, the inclination angle of the local conical surface of the pocket bottom Pb is the angle of the roller rolling surface of the roller 4 held in the pocket P relative to the tangent direction of the roller axis at the following position, which is an axial position from the axial base end edge 8 of the pocket bottom Pb to 10% to 30% of the axial length of the roller.

[0060] Whether the movement of the held roller 4 in the pocket P of the retainer 5 is suppressed depends on the relationship between the shape of the roller 4 and the cone inclination angle of the local cone surface Pb at the bottom of the pocket P. The results of studying this relationship are shown in Table 2. The value in the "Tangent Position" column in the table is, for example, 10%, which means that the inclination angle of the local cone surface at the bottom of the pocket is equal to the tangent angle of the rolling surface of the roller 4 held in the pocket P at the position from the axial base end edge 8 of the bottom of the pocket Pb to the axial length L2 of 10% of the roller length L. In the column of the roller movement suppression effect in the table, the symbol "0" indicates that the movement of the roller 4 is fully suppressed by the retainer 5, the symbol "△" indicates that there is no problem in suppressing the movement of the roller, and the symbol "×" indicates that there is a problem in suppressing the movement of the roller.

[0061] [Table 2]

[0062] Tangent position 0％ 10％ 20％ 30％ 40％ 50％ Roller motion suppression effect × 〇 〇 〇 △ ×

[0063] Taking the above into consideration, it can be seen that in the comb-shaped cut retainer of the self-aligning roller bearing of the present invention, the conical inclination angle of the local conical surface at the bottom of the pocket P is preferably the angle of the rolling surface of the roller 4 at the following position relative to the tangential direction of the axial direction of the roller 4, which is a position greater than 10% and less than 30% of the roller length L of the roller 4 retained in the pocket P.

[0064] By setting the conical inclination angle of the local conical surface of the pocket P of the cage 5 to be within an appropriate numerical range in this manner, the movement of the roller 4 held in the pocket P of the cage 5 can be sufficiently suppressed.

[0065] [Fourth Embodiment]

[0066] Figure 5 A fourth embodiment of the present invention is shown. Figure 5 This is a longitudinal cross-sectional view of a self-aligning roller bearing. In the comb-cut retainer, the outer diameter of the annular portion 5a of the retainer 5 is made larger than the outer diameter of the columnar portion 5b of the retainer 5, so that the retainer 5 and the inner circumferential surface of the outer ring 2 slide and rotate, thereby becoming an outer ring guided retainer. As a result, even in an environment where the outer ring rotates or vibrations are applied, the rollers can be guided while the movement of the rollers is fully suppressed.

[0067] [Fifth Embodiment]

[0068] Figure 6 and Figure 7 The fifth embodiment of the present invention is shown. Figure 6 As shown in FIG. 1 , the left and right roller rows CL and CR are provided with separate comb-shaped cut retainers 5L and 5R, respectively. Figure 7 , the comb-shaped cutting retainer 5R is shown along Figure 6 VII-VII line cross-sectional view. A plurality of columnar portions 5Rb protruding from the annular portion 5Ra of the comb-shaped cut retainer 5R form pockets P, and the roller 4 is retained in the pockets P. The same is true for the other comb-shaped cut retainer 5L. Thus, for example, even if a load is generated on one row of rollers and a difference occurs in the revolution speeds of the left and right roller rows CL and CR, the retainers 5L and 5R can rotate independently relative to the left and right roller rows CL and CR. Therefore, it is difficult for the roller 4 to contact the retainers 5L and 5R due to the difference in the revolution speeds of the left and right roller rows CL and CR, thereby reducing abnormalities and wear of the retainers and the occurrence of abnormalities due to the contact.

[0069] As mentioned above, although the preferred embodiments have been described with reference to the drawings, various additions, changes, and deletions can be made without departing from the gist of the present invention.

[0070] Therefore, such a case is also included in the scope of the present invention.

[0071] [Explanation of symbols]

[0072] 1...Self-aligning roller bearings

[0073] 2…Outer ring

[0074] 3…Inner Circle

[0075] 4... Roller

[0076] 5. Retainer

[0077] 5a……Annular part

[0078] 5b……Column

[0079] 7...Axial front edge

[0080] 8...Axial base edge

[0081] Pa... local cylindrical surface

[0082] Pb... Local cone

[0083] P……pocket hole.

Claims

1. A self-aligning roller bearing comprising an outer ring, an inner ring, a plurality of rollers arranged in two rows of rings between the outer ring and the inner ring, and a cut retainer for retaining the plurality of rollers, characterized in that: The cut retainer is a comb-shaped cut retainer, which includes an annular portion arranged between the two rows of rollers and a plurality of column portions protruding from the axial side surfaces on both sides of the annular portion, and the column portions adjacent to each other in the circumferential direction of the plurality of column portions form pockets for freely rolling and retaining each roller. The pocket has: a pocket bottom connected to the annular portion and located on the root side of the column portion, and a pocket entrance extending from the axial front end edge of the pocket bottom to the front end of the column portion. The pocket bottom has a partial conical shape whose diameter decreases from the axial front end edge toward the root side of the column portion, and the pocket entrance has a partial cylindrical shape.

2. The self-aligning roller bearing according to claim 1, characterized in that: The axial length of the pocket bottom is 20-40% of the axial length of the roller.

3. The self-aligning roller bearing according to claim 1 or 2, characterized in that: The inclination angle of the local conical surface is the angle of the rolling surface of the roller relative to the tangent direction of the roller axis at the following position, which is an axial position from the axial base end edge of the bottom of the pocket to 10 to 30% of the axial length of the roller.

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