Double-row angular ball bearing and angular ball bearing

Abstract

To provide a technique for facilitating assembly work.SOLUTION: In an angular ball bearing 1, when an inner ring 2 is arranged such that an inner ring back face 2c faces downward in a vertical direction, and when a first holder-held ball 50 configured of a first holder 6 and a plurality of first balls 8 held by the first holder 6 is arranged in a first inner ring raceway groove 14, a part of the first ball 8 positioned at a lowermost side in a vertical direction, of the plurality of first balls 8, is inside a first edge part 14a in a radial direction in a case where a first inferior angle θ1 formed between a center axis C3 of the first holder 6 and a center axis C1 of the inner ring 2 is 0° or more and less than a first angle, and a part of the first ball 8 positioned at the lowermost side in the vertical direction is inside the first edge part 14a in the radial direction and the first holder 6 comes into contact with the inner ring 2 in a case where the first holder 6 does not contact the inner ring 8 and the first inferior angle θ1 is the first angle or more.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates to a double-row angular contact ball bearing and an angular contact ball bearing. [Background technology]

[0002] The following Patent Document 1 discloses a double-row angular contact ball bearing. This double-row angular contact ball bearing is a tandem double-row angular contact ball bearing. This double-row angular contact ball bearing includes an inner ring, an outer ring, a plurality of balls arranged in double rows, and two cages that hold the plurality of balls. The two cages include a first cage and a second cage that has a diameter larger than that of the first cage. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-106633 A Summary of the Invention [Problem to be solved by the invention]

[0004] FIG. 8(a) shows a method for assembling the above-mentioned double row angular contact ball bearing. The second ball with cage 104 and the first ball with cage 102 are placed on an inner ring 100 arranged so that its central axis is aligned vertically, and then an outer ring is attached on top of the second ball with cage 104 and the first ball with cage 102. The first ball and cage assembly 102 includes a plurality of balls 102a and a first cage 102b that holds the plurality of balls 102a. The second ball and cage assembly 104 includes a plurality of balls 104a and a second cage 104b that holds the plurality of balls 104a. The diameter of the second cage 104b is larger than the diameter of the first cage 102b.

[0005] FIG. 8( b ) is a cross-sectional view showing another example in which the first cage-equipped ball 102 is disposed in the inner ring 100 . As shown in Figure 8(a), when the second cage-equipped balls 104 are arranged on the inner ring 100 so that multiple balls 102a contact near the nominal contact point in the inner ring raceway groove 100a of the inner ring 100, there is almost no inclination between the center axis of the inner ring 100 and the center axis of the second cage 104b. However, as shown in FIG. 8(b), some of the balls 102a may become separated from the nominal contact point. In this case, the central axis of the inner ring 100 and the central axis of the second cage 104b become inclined, and as a result, the entire first cage-equipped ball 102 becomes inclined with respect to the inner ring 100. A similar phenomenon occurs with the second ball and cage assembly 104 as well.

[0006] If the balls and cages 102, 104 are tilted relative to the inner ring 100, when the outer ring is attached to the balls and cages 102, 104, the balls 102a will be pinched between the outer ring and the edge of the inner ring raceway groove 100a and shoulder, making the assembly process difficult. [Means for solving the problem]

[0007] The double-row angular contact ball bearing according to the embodiment includes an inner ring, an outer ring, a first ball and cage assembly, a second cage, and a plurality of second balls. The first ball and cage assembly includes a first cage and a plurality of first balls. The inner ring has an inner ring front surface on a first axial side and an inner ring back surface on a second axial side, and includes a first inner ring raceway groove, a first inner ring shoulder, and a second inner ring raceway groove on an outer periphery between the inner ring front surface and the inner ring back surface from the first axial side to the second axial side. The first inner ring raceway groove and the first inner ring shoulder are connected. The outer ring includes a first outer ring raceway groove and a second outer ring raceway groove on an inner periphery from the first axial side to the second axial side. The first cage includes a plurality of first pillars, a first annular body, and a plurality of first pockets. The first columns are connected to the first annular body at either a first axial side of the first annular body or a second axial side of the first annular body. A space surrounded by two adjacent first columns and the first annular body is a first pocket. Each of the first pockets has an inner surface that holds the first ball so that it does not fall out of the first pocket. The first caged ball holds one of the first balls in each of the first pockets. The second cage includes a plurality of second columns, a second annular body, and a plurality of second pockets. The second columns are connected to the second annular body at either a first axial side of the second annular body or a second axial side of the second annular body. A space surrounded by two adjacent second columns and the second annular body is a second pocket. Each of the second pockets holds the second ball. A first inner ring raceway contact diameter of the first inner ring raceway groove is smaller than a second inner ring raceway contact diameter of the second inner ring raceway groove. A first outer ring raceway contact diameter of the first outer ring raceway groove is smaller than a second outer ring raceway contact diameter of the second outer ring raceway groove.When the inner ring is positioned with the inner ring back surface facing vertically downward and the first caged ball is placed in the first inner ring raceway groove from the first axial side, if a first minor angle formed between the center axis of the first cage and the center axis of the inner ring is greater than 0° and less than a first angle, a portion of the first ball that is located furthest vertically downward among the multiple first balls is radially inward from the first edge portion and the first cage does not contact the inner ring, and if the first minor angle is greater than or equal to the first angle, a portion of the first ball that is located furthest vertically downward is radially inward from the first edge portion and the first cage contacts the inner ring. Effect of the Invention

[0008] According to the present disclosure, the assembly work can be made easier. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing an example of an angular contact ball bearing according to an embodiment. [Diagram 2] FIG. 2 is a perspective view showing the second cage. [Diagram 3] FIG. 3 is a perspective view of the second cage shown at a different angle from that in FIG. 2, and shows an enlarged portion of the second cage. [Figure 4] FIG. 4 is a cross-sectional view showing an example of an intermediate assembly when assembling an angular ball bearing. [Diagram 5] FIG. 5 is a cross-sectional view showing another example of the intermediate assembly. [Figure 6] FIG. 6 is a diagram for explaining an assembly operation of a conventional angular contact ball bearing. [Figure 7] FIG. 7 is a perspective view showing a second cage according to a modified example. [Figure 8] FIG. 8(a) is a cross-sectional view showing an example in which a first caged ball is arranged on the inner ring of a conventional double-row angular contact ball bearing, and FIG. 8(b) is a cross-sectional view showing another example in which a first caged ball is arranged on the inner ring. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] First, the contents of the embodiment will be listed and described. [Overview of the embodiment] (1) A double-row angular ball bearing according to an embodiment includes an inner ring, an outer ring, a first ball and cage assembly, a second cage, and a plurality of second balls. The first ball and cage assembly includes a first cage and a plurality of first balls. The inner ring has an inner ring front surface on a first axial side and an inner ring back surface on a second axial side, and includes a first inner ring raceway groove, a first inner ring shoulder, and a second inner ring raceway groove on an outer periphery between the inner ring front surface and the inner ring back surface from the first axial side to the second axial side. The first inner ring raceway groove and the first inner ring shoulder are connected. The outer ring includes a first outer ring raceway groove and a second outer ring raceway groove on an inner periphery from the first axial side to the second axial side. The first cage includes a plurality of first pillars, a first annular body, and a plurality of first pockets. The first columns are connected to the first annular body at either a first axial side of the first annular body or a second axial side of the first annular body. A space surrounded by two adjacent first columns and the first annular body is a first pocket. Each of the first pockets has an inner surface that holds the first ball so that it does not fall out of the first pocket. The first caged ball holds one of the first balls in each of the first pockets. The second cage includes a plurality of second columns, a second annular body, and a plurality of second pockets. The second columns are connected to the second annular body at either a first axial side of the second annular body or a second axial side of the second annular body. A space surrounded by two adjacent second columns and the second annular body is a second pocket. Each of the second pockets holds the second ball. A first inner ring raceway contact diameter of the first inner ring raceway groove is smaller than a second inner ring raceway contact diameter of the second inner ring raceway groove. A first outer ring raceway contact diameter of the first outer ring raceway groove is smaller than a second outer ring raceway contact diameter of the second outer ring raceway groove.When the inner ring is positioned with the inner ring back surface facing vertically downward and the first caged ball is placed in the first inner ring raceway groove from the first axial side, if a first minor angle formed between the center axis of the first cage and the center axis of the inner ring is greater than 0° and less than a first angle, a portion of the first ball that is located furthest vertically downward among the multiple first balls is radially inward from the first edge portion and the first cage does not contact the inner ring, and if the first minor angle is greater than or equal to the first angle, a portion of the first ball that is located furthest vertically downward is radially inward from the first edge portion and the first cage contacts the inner ring.

[0011] The double-row angular ball bearing having the above configuration is configured so that when the first retainer is inclined relative to the inner ring and the first minor angle becomes the first angle, the first retainer comes into contact with the inner ring, thereby preventing the first minor angle from becoming larger than the first angle. With the above configuration, when the first retainer-attached ball is placed on the inner ring during assembly of a double-row angular contact ball bearing, the first retainer-attached ball is prevented from tilting unnecessarily large relative to the inner ring, making it easier to attach the outer ring to the first retainer-attached ball. As a result, the assembly work can be facilitated.

[0012] (2) In the above-mentioned double-row angular contact ball bearing, a preferred double-row angular contact ball bearing is configured such that a second edge portion on a first axial side of the first inner ring raceway groove is connected to the inner ring front surface, the first retainer has a first surface facing the inner ring front surface, and when the first minor angle is greater than or equal to 0° and less than the first angle, an axial gap is provided between the first surface and the inner ring front surface, and when the first minor angle is greater than or equal to the first angle, the first surface and the inner ring front surface contact each other. In this case, contact between the first surface and the inner ring front surface prevents the first minor angle from becoming larger than the first angle.

[0013] (3) In the above-mentioned double-row angular ball bearing, the first annular body is a first small-diameter annular body connected to a first axial side of the multiple columns, and the first small-diameter annular body has an annular main body portion and a first engagement portion protruding from the annular main body portion toward a front surface of the inner ring, and the first surface is configured to be provided at the tip of the first engagement portion. In this case, the first engagement portion comes into contact with the inner ring, thereby preventing the first minor angle from becoming larger than the first angle.

[0014] (4) In the double-row angular contact ball bearing, an end face of the first large-diameter annular body on a second axial side may have a chamfered portion that defines a gap between the first large-diameter annular body and the second cage. In this case, contact between the first retainer and the second retainer is suppressed.

[0015] (5) A double-row angular ball bearing from another viewpoint includes an inner ring, an outer ring, a first cage, a plurality of first balls, and a second caged ball assembly. The second caged ball assembly includes a second cage and a plurality of second balls. The inner ring has an inner ring front surface on a first axial side and an inner ring back surface on a second axial side, and includes a first inner ring raceway groove, a second inner ring raceway groove, and a second inner ring shoulder on an outer periphery between the inner ring front surface and the inner ring back surface from the first axial side to the second axial side. The second inner ring raceway groove and the second inner ring shoulder are connected. The outer ring includes a first outer ring raceway groove and a second outer ring raceway groove on an inner periphery from the first axial side to the second axial side. The first cage includes a plurality of first posts, a first annular body, and a plurality of first pockets. The first columns are connected to the first annular body at either a first axial side of the first annular body or a second axial side of the first annular body. A space surrounded by two adjacent first columns and the first annular body is a first pocket. Each of the first pockets holds the first ball. The second cage includes a plurality of second columns, a second annular body, and a plurality of second pockets. The second columns are connected to the second annular body at either a first axial side of the second annular body or a second axial side of the second annular body. A space surrounded by two adjacent second columns and the second annular body is a second pocket. Each of the second pockets has an inner surface that holds the second ball so that it does not fall out of the first pocket. The second cage-equipped ball holds one of the second balls in each of the second pockets. A first inner ring raceway contact diameter of the first inner ring raceway groove is smaller than a second inner ring raceway contact diameter of the second inner ring raceway groove. A first outer ring raceway contact diameter of the first outer ring raceway groove is smaller than a second outer ring raceway contact diameter of the second outer ring raceway groove.When the inner ring is positioned with the inner ring back surface facing vertically downward, and the second caged ball is placed in the second inner ring raceway groove from the first axial side, if a second minor angle formed between the central axis of the second cage and the central axis of the inner ring is greater than 0° and less than a second angle, a portion of the second ball that is located furthest vertically downward among the multiple second balls is radially inward from the third edge portion, and the second cage does not contact the inner ring, and if the second minor angle is greater than or equal to the second angle, a portion of the second ball that is located furthest vertically downward is radially inward from the third edge portion, and the second cage contacts the inner ring.

[0016] According to the above configuration, when the second retainer is tilted relative to the inner ring and the second minor angle becomes the second angle, the second retainer is configured to come into contact with the inner ring, thereby preventing the second minor angle from becoming larger than the second angle. This prevents the second retainer-attached ball from tilting unnecessarily large relative to the inner ring when the second retainer-attached ball is placed on the inner ring during assembly of a double-row angular contact ball bearing, making it easier to subsequently install the outer ring. As a result, the assembly work can be facilitated.

[0017] (6) In the above double-row angular contact ball bearing, a preferred double-row angular contact ball bearing is configured such that the outer peripheral surface further has an annular surface facing a first axial side between the first inner ring raceway groove and the second inner ring raceway groove, a fourth edge portion on the first axial side of the second inner ring raceway groove is connected to the annular surface, and when the second retainer has a second surface facing the annular surface, an axial gap is provided between the second surface and the annular surface when the second minor angle is 0° or more and less than the second angle, and when the second minor angle is the second angle or more, the second surface and the annular surface contact each other. In this case, contact between the second surface and the inner ring back surface prevents the second minor angle from becoming larger than the second angle.

[0018] (7) From another perspective, an angular ball bearing includes an inner ring, an outer ring, and a ball with a cage. The ball with cage includes a cage and a plurality of balls. The inner ring has an inner ring front surface on a first axial side and an inner ring back surface on a second axial side, and includes an inner ring raceway groove and an inner ring shoulder on an outer periphery between the inner ring front surface and the inner ring back surface, from the first axial side to the second axial side. The inner ring raceway groove and the inner ring shoulder are connected. The outer ring has an outer ring raceway groove on an inner periphery, from the first axial side to the second axial side. The cage includes a plurality of pillars, an annular body, and a plurality of pockets. The plurality of pillars are connected to the annular body on one of the first axial side of the annular body or the second axial side of the annular body. A space surrounded by two adjacent pillars and the annular body is a pocket. Each of the plurality of pockets has an inner surface that holds the ball so that it does not fall out of the pocket. The ball and cage assembly holds one ball in each of a plurality of pockets. When the inner ring is arranged with the inner ring back surface facing vertically downward and the ball and cage assembly is placed on the inner ring raceway groove from a first axial side, if the minor angle formed by the central axis of the cage and the central axis of the inner ring is equal to or greater than 0° and less than a first angle, some of the balls located at the lowest vertical position among the plurality of balls are radially inward from the first edge portion and the cage does not contact the inner ring, and if the minor angle is equal to or greater than the first angle, some of the balls located at the lowest vertical position are radially inward from the first edge portion and the cage contacts the inner ring. The above configuration also facilitates assembly work.

[0019] (8) In the angular contact ball bearing of (7) above, a preferred double-row angular contact ball bearing is configured such that, when a second edge portion on a first axial side of the inner ring raceway groove is connected to the inner ring front surface and the retainer has a first surface facing the inner ring front surface, when the minor angle is 0° or more and less than the first angle, an axial gap is provided between the first surface and the inner ring front surface, and when the minor angle is the first angle or more, the first surface and the inner ring front surface contact each other. In this case, contact between the first surface and the inner ring front surface prevents the minor angle from becoming larger than the first angle.

[0020] [Details of the embodiment] Hereinafter, preferred embodiments will be described with reference to the drawings. [Overall structure] 1 is a cross-sectional view showing an example of an angular contact ball bearing according to an embodiment. This angular contact ball bearing is a double-row angular contact ball bearing. More specifically, this angular contact ball bearing is a tandem double-row angular contact ball bearing. The angular contact ball bearing 1 includes an inner ring 2, an outer ring 4, a first cage 6, a plurality of first balls 8, a second cage 10, and a plurality of second balls 12. The first cage 6 and the second cage 10 are disposed between the inner ring 2 and the outer ring 4. The diameter of the second cage 10 is larger than the diameter of the first cage 6. The second cage 10 is disposed axially aligned with the first cage 6. In the following description, the direction along the central axis C1 of the angular contact ball bearing 1 is the axial direction. The first axial side is the right side in Fig. 1, which is the front surface 2b side of the inner ring 2. The second axial side is the left side in Fig. 1, which is the back surface 2c side of the inner ring 2. The direction perpendicular to the central axis C1 is the radial direction. The direction along a circle centered on the central axis C1 is the circumferential direction.

[0021] The inner ring 2 is an annular member formed from bearing steel etc. The inner ring 2 has an outer peripheral surface 2a, an inner ring front surface 2b, an inner ring back surface 2c, and a bearing inner diameter surface 2d. The outer peripheral surface 2 a has a first inner ring raceway groove 14 , a first inner ring shoulder 16 , an annular surface 18 , a second inner ring raceway groove 20 , and a second inner ring shoulder 22 . A first inner ring raceway groove 14, a first inner ring shoulder 16, an annular surface 18, a second inner ring raceway groove 20, and a second inner ring shoulder 22 are provided on the outer peripheral surface 2a in sequence from the first axial side to the second axial side. The inner ring front surface 2b is a side surface of the inner ring 2 on the first inner ring raceway groove 14 side in the axial direction. The inner ring back surface 2c is a side surface of the inner ring 2 on the second inner ring raceway groove 20 side in the axial direction.

[0022] The first inner ring raceway groove 14 is a raceway along which the multiple first balls 8 roll. The first inner ring raceway groove 14 has a first edge portion 14a and a second edge portion 14b. The groove radius of the first inner ring raceway groove 14 is 50.5% to 60% of the diameter of the first ball 8 . The first edge portion 14a is an edge portion on the inner ring back surface 2c side of the first inner ring raceway groove 14. The first edge portion 14a is connected to a first inner ring shoulder portion 16. The first inner race shoulder portion 16 is a cylindrical surface facing radially outward. Moreover, the second edge portion 14b is an edge portion on the inner ring front surface 2b side of the first inner ring raceway groove 14. The second edge portion 14b is connected to the outer circumferential edge of the inner ring front surface 2b.

[0023] The second inner ring raceway groove 20 is a raceway along which the multiple second balls 12 roll. The diameter of the second inner ring raceway groove 20 is larger than the diameter of the first inner ring raceway groove . The second inner ring raceway groove 20 has a third edge portion 20a and a fourth edge portion 20b. The groove radius of the second inner ring raceway groove 20 is 50.5% to 60% of the diameter of the second ball 12 . The third edge portion 20a is an edge portion on the inner ring back surface 2c side of the second inner ring raceway groove 20. The third edge portion 20a is connected to the second inner ring shoulder portion 22. The second inner race shoulder 22 is a cylindrical surface facing radially outward and is provided between the outer circumferential edge of the inner race back surface 2c and the third edge portion 20a. Moreover, the fourth edge portion 20b is an edge portion on the inner ring front surface 2b side of the second inner ring raceway groove 20. The fourth edge portion 20b is connected to the outer circumferential edge of the annular surface . The annular surface 18 is a surface facing the inner ring front surface 2b in the axial direction. The annular surface 18 is provided between the fourth edge portion 20b and the first inner ring shoulder portion 16.

[0024] The outer ring 4 is an annular member made of bearing steel or the like. The outer ring 4 is arranged concentrically on the outer periphery of the inner ring 2. The outer ring 4 has an inner circumferential surface 4a. The inner circumferential surface 4a has a first outer ring raceway groove 24 and a second outer ring raceway groove 26. The first outer ring raceway groove 24 is a raceway along which the multiple first balls 8 roll. The first outer ring raceway groove 24 faces the first inner ring raceway groove 14. The groove radius of the first outer ring raceway groove 24 is 50.5% to 60% of the diameter of the first ball 8 . The second outer ring raceway groove 26 is a raceway along which the plurality of second balls 12 roll. The second outer ring raceway groove 26 faces the second inner ring raceway groove 20. The groove radius of the second outer ring raceway groove 26 is 50.5% to 60% of the diameter of the second ball 12 .

[0025] The plurality of first balls 8 are members made of bearing steel or the like. The multiple first balls 8 are arranged circumferentially so as to be able to roll freely between the first inner ring raceway groove 14 and the first outer ring raceway groove 24. The diameter of a circle passing through the nominal contact points between the multiple first balls 8 and the first inner ring raceway groove 14 is the first inner ring raceway contact diameter. The diameter of a circle passing through the nominal contact points between the multiple first balls 8 and the first outer ring raceway groove 24 is the first outer ring raceway contact diameter. The second balls 12 are members formed of bearing steel or the like. The second balls 12 are arranged circumferentially between the second inner ring raceway groove 20 and the second outer ring raceway groove 26 so as to be able to roll freely. The diameter of a circle passing through the nominal contact points between the second balls 12 and the second inner ring raceway groove 20 is the second inner ring raceway contact diameter. The diameter of a circle passing through the nominal contact points between the second balls 12 and the second outer ring raceway groove 26 is the second outer ring raceway contact diameter. The first inner ring raceway contact diameter is smaller than the second inner ring raceway contact diameter. The first outer ring raceway contact diameter is smaller than the second outer ring raceway contact diameter.

[0026] The first cage 6 is an annular member that holds a plurality of first balls 8. The first cage 6 is formed by injection molding using polyamide, phenolic resin, or the like. The first cage 6 includes a first small diameter annular body 30 which is a first annular body, a first large diameter annular body 32 which is a first annular body, a plurality of pillars 33, and a plurality of first pockets . The multiple first pockets 34 are provided between the first small diameter annular body 30, the first large diameter annular body 32, and a pair of adjacent pillars 33. Each of the multiple first pockets 34 has an inner side surface 34a of the first pocket 34. The inner side surface 34a of the first pocket 34 has a concave curved surface shape that holds the first balls 8 so that they do not fall out of the first pocket 34. The first cage 6 is a squirrel-cage cage.

[0027] The second cage 10 is an annular member that holds a plurality of second balls 12. Similar to the first cage 6, the second cage 10 is formed by injection molding using polyamide, phenolic resin, or the like. The second retainer 10 includes a second small diameter annular body 40 which is a second annular body, a second large diameter annular body 42 which is a second annular body, a plurality of pillars 43, and a plurality of second pockets 44. The multiple second pockets 44 are provided between the second small diameter annular body 40, the second large diameter annular body 42, and a pair of adjacent pillars 43. Each of the multiple second pockets 44 has an inner side surface 44a of the second pocket 44. The inner side surface 44a of the second pocket 44 has a concave curved surface shape that holds the second balls 12 so that they do not fall out of the second pocket 44. The second cage 10 is a cage cage.

[0028] [Regarding the cage] 2 is a perspective view showing the second retainer 10. The retainer described here is the second retainer 10, while the configuration of the first retainer 6 is similar to that of the retainer described. As described above, the second retainer 10 includes the second small diameter annular body 40, the second large diameter annular body 42, a plurality of posts 43, and a plurality of second pockets 44.

[0029] The second small diameter annular body 40 is an annular body centered on the central axis C2 of the second cage 10. The second large diameter annular body 42 is an annular body centered on the central axis C2, and is disposed concentrically with the second small diameter annular body 40. The outer diameter dimension of the second large diameter annular body 42 is larger than the outer diameter dimension of the second small diameter annular body 40. The multiple pillars 43 are arranged at equal intervals in the circumferential direction, and connect the second small diameter annular body 40 and the second large diameter annular body 42 together.

[0030] The plurality of second pockets 44 are defined by a pair of adjacent pillars 43 among the plurality of pillars 43, the second small diameter annular body 40, and the second large diameter annular body . The second pockets 44 are provided at equal intervals along the circumferential direction. The second pockets 44 accommodate the second balls 12 one by one in the internal space of each of the second pockets 44, thereby holding the second balls 12 at equal intervals in the circumferential direction.

[0031] FIG. 3 is a perspective view of the second retainer 10 shown at a different angle from that in FIG. 2, and is an enlarged view of a portion of the second retainer 10. As shown in FIG. As shown in FIG. 3 and FIG. 1, the second small diameter annular body 40 has an annular main body portion 40a and a second engagement portion 40b. 1, the second engagement portion 40b protrudes from the annular main body portion 40a toward the annular surface 18. The second engagement portion 40b is provided in an annular shape around the entire circumference of the annular main body portion 40a. A tip surface 40b1 (second surface) of the second engagement portion 40b and the annular surface 18 face each other.

[0032] As shown in FIG. 1, the first small diameter annular body 30 of the first cage 6, like the second small diameter annular body 40 of the second cage 10, has an annular main body portion 30a and a first engagement portion 30b. The first engagement portion 30b protrudes from the annular main body portion 30a toward the inner ring front surface 2b. The first engagement portion 30b is provided in an annular shape around the entire circumference of the annular main body portion 30a. A tip end surface 30b1 (first surface) of the first engagement portion 30b and the inner ring front surface 2b face each other.

[0033] In addition, the end face of the first large diameter annular body 32 of the first retainer 6 on the axial side of the inner ring back surface 2c has an end face portion 32b along the radial direction and a chamfered portion 32a provided on the outside of the end face portion 32b. The chamfered portion 32a defines an annular gap between itself and the second small diameter annular body 40 of the second retainer 10. The chamfered portion 32a can prevent the first cage 6 and the second cage 10 from coming into contact with each other.

[0034] [Assembling angular contact ball bearing 1] FIG. 4 is a cross-sectional view showing an example of an intermediate assembly when assembling the angular ball bearing 1. As shown in FIG. The angular contact ball bearing 1 of this embodiment is assembled as follows: First, the inner ring 2 is placed with the inner ring back surface 2c facing vertically downward, and the second ball and cage assembly 60 and the first ball and cage assembly 50 are placed on the placed inner ring 2, as shown in FIG. The first ball and cage assembly 50 is composed of a first cage 6 and a plurality of first balls 8 held by the first cage 6. In other words, the first ball and cage assembly 50 is a ball and cage assembly (assembly) in which a plurality of first balls 8 are held by the first cage 6. The second ball and cage assembly 60 is composed of a second cage 10 and a plurality of second balls 12 held by the second cage 10. In other words, the second ball and cage assembly 60 is a ball and cage assembly (assembly) in which a plurality of second balls 12 are held by the second cage 10. The second ball and cage assembly 60 and the first ball and cage assembly 50 are mounted on the inner ring 2 to form an intermediate assembly.

[0035] The second caged ball 60 (second cage 10) is placed in the second inner ring raceway groove 20. The diameter of the second inner ring raceway groove 20 is larger than the diameter of the first inner ring raceway groove 14. Therefore, first, the second ball and cage assembly 60 is placed in the second inner ring raceway groove 20, and then the first ball and cage assembly 50 is placed in the first inner ring raceway groove . After the balls and cages 50, 60 are placed in the inner ring raceway grooves 14, 20, the outer ring 4 is attached to the intermediate assembly, thereby obtaining the angular ball bearing 1.

[0036] 4 are arranged so as to contact the vicinity of the inner ring nominal contact point P1 in the first inner ring raceway groove 14. Therefore, the central axis C3 of the first cage 6 is hardly inclined with respect to the central axis C1 of the inner ring 2 and is substantially aligned with the central axis C1. Similarly to the first balls 8, the second balls 12 are also arranged to contact the second inner ring raceway groove 20 near the inner ring nominal contact point P2. Therefore, the central axis C2 of the second cage 10 is hardly inclined with respect to the central axis C1 of the inner ring 2 and is substantially aligned with the central axis C1.

[0037] In other words, the first cage 6 (first cage-attached ball 50) and the second cage 10 (second cage-attached ball 60) in FIG. 4 is supported by a plurality of first balls 8. For this reason, the first cage 6 is not in contact with the inner ring 2. More specifically, an axial gap is provided between the tip end surface 30b1 of the engagement portion 30b of the first small diameter annular body 30 in the first cage 6 and the inner ring front surface 2b of the inner ring 2.

[0038] The second cage 10 is also supported by a plurality of second balls 12. For this reason, the second cage 10 is not in contact with the inner ring 2. More specifically, an axial gap is provided between the tip end surface 40b1 of the engagement portion 40b of the second small diameter annular body 40 in the second cage 10 and the annular surface 18 of the inner ring 2.

[0039] FIG. 5 is a cross-sectional view showing another example of the intermediate assembly. FIG. 5 shows a state in which the first cage 6 (first cage-attached balls 50) and the second cage 10 (second cage-attached balls 60) are inclined with respect to the inner ring 2. As shown in FIG. The first ball 8 shown in Fig. 5 is located at the lowermost position in the vertical direction among the multiple first balls 8 because the first ball with cage 50 is tilted. Similarly, the second ball 12 shown in Fig. 5 is located at the lowermost position in the vertical direction among the multiple second balls 12 because the second ball with cage 60 is tilted. Fig. 5 shows a cross section of a portion of the first balls 8 that is located at the lowest vertical position among the plurality of first balls 8, taken along a plane including the central axis C1 of the inner ring 2 and the central axis C3 of the first cage 6. Fig. 5 also shows a cross section of a portion of the second balls 12 that is located at the lowest vertical position among the plurality of second balls 12, taken along a plane including the central axis C1 of the inner ring 2 and the central axis C2 of the second cage 10. In Fig. 5, the circumferential position of the first ball 8 that is located at the lowest vertical position coincides with the circumferential position of the second ball 12 that is located at the lowest vertical position, but this is shown as such only for convenience of illustration, and they may differ.

[0040] 5 is in contact with the inner ring 2 by tilting with respect to the inner ring 2. More specifically, a tip end surface 30b1 of the engagement portion 30b of the first small diameter annular body 30 in the first cage 6 is in contact with the inner ring front surface 2b of the inner ring 2. A tip end surface 30b1 of the engagement portion 30b comes into contact with the inner ring front surface 2b of the inner ring 2, so that the first cage 6 is maintained in an inclined state with respect to the inner ring 2. In other words, the tip surface 30b1 of the engagement portion 30b comes into contact with the inner ring front surface 2b of the inner ring 2, thereby preventing the first cage 6 (first cage-attached ball 50) from tilting more than shown in FIG.

[0041] Also, as shown in Figure 5, when the tip surface 30b1 of the engagement portion 30b contacts the inner ring front surface 2b of the inner ring 2, the first minor angle θ1 formed by the central axis C3 of the first retainer 6 and the central axis C1 of the inner ring 2 becomes a first angle K1. Therefore, as shown in FIG. 4, when the first cage 6 is not in contact with the inner ring 2, the first minor angle θ1 changes within a range from 0° to a value less than the first angle K1.

[0042] As shown in Fig. 5, the straight line L1 intersects with the first ball 8. The straight line L1 is a straight line parallel to the vertical direction that passes through the first edge portion 14a. In other words, a part of the first ball 8 in Fig. 5 is located radially inward from the first edge portion 14a. In FIG. 4, a portion of the first ball 8 is also located radially inward of the first edge portion 14a.

[0043] Thus, in the angular ball bearing 1 of this embodiment, when the first retainer-attached ball 50 is placed in the first inner ring raceway groove 14, if the first minor angle θ1 is greater than 0° and less than the first angle K1, a portion of the first ball 8 that is located furthest vertically downward among the multiple first balls 8 is radially inward from the first edge portion 14a, and the first retainer 6 does not contact the inner ring 2. Furthermore, when the first minor angle θ1 is greater than or equal to the first angle K1, a portion of the first ball 8 located at the lowest vertical position is radially inward from the first edge portion 14a, and the first retainer 6 contacts the inner ring 2.

[0044] According to the above configuration, when the first retainer 6 is inclined relative to the inner ring 2 and the first minor angle θ1 becomes the first angle K1, the first retainer 6 is configured to come into contact with the inner ring 2, thereby preventing the first minor angle θ1 from becoming larger than the first angle K1. As a result, when the first ball and cage assembly 50 is placed on the inner ring 2 during assembly of the angular ball bearing 1, it is possible to prevent the first ball and cage assembly 50 from tilting unnecessarily large relative to the inner ring 2, facilitating the subsequent attachment of the outer ring 4. As a result, the assembly work can be facilitated.

[0045] In addition, in the angular ball bearing 1 configured as described above, when the first minor angle θ1 is greater than or equal to 0° and less than the first angle K1, an axial gap is provided between the tip surface 30b1 (first surface) of the engagement portion 30b and the inner ring front surface 2b of the inner ring 2, and when the first minor angle θ1 is greater than or equal to the first angle K1, the tip surface 30b1 and the inner ring front surface 2b come into contact with each other. Therefore, contact between the tip face 30b1 and the inner ring front face 2b can prevent the first minor angle θ1 from becoming larger than the first angle K1, and can prevent contact between the engagement portion 30b and the inner ring front face 2b when the central axis C3 of the first retainer coincides with the central axis C1 of the inner ring 2 in the angular ball bearing 1 after assembly work.

[0046] 5 is in contact with the inner ring 2 by tilting with respect to the inner ring 2, similar to the first cage 6. More specifically, the tip surface 40b1 of the engagement portion 40b of the second small diameter annular body 40 in the second cage 10 is in contact with the annular surface 18 of the inner ring 2. The tip end surface 40b1 of the engagement portion 40b contacts the annular surface 18, so that the second cage 10 is maintained in an inclined state with respect to the inner ring 2. In other words, the tip surface 40b1 of the engagement portion 40b contacts the annular surface 18 of the inner ring 2, thereby preventing the second cage 10 (second cage-mounted ball 60) from tilting more than shown in FIG.

[0047] Also, as shown in Figure 5, when the tip surface 40b1 of the engagement portion 40b contacts the annular surface 18 of the inner ring 2, the second minor angle θ2 formed by the central axis C2 of the second retainer 10 and the central axis C1 of the inner ring 2 becomes a second angle K2. Therefore, as shown in FIG. 4, when the second cage 10 is not in contact with the inner ring 2, the second minor angle θ2 changes within a range from 0° to a value less than the second angle K2.

[0048] 5, the straight line L2 intersects with the second ball 12. The straight line L2 is a straight line parallel to the vertical direction that passes through the third edge portion 20a. In other words, a part of the second ball 12 in FIG. 5 is located radially inward from the third edge portion 20a. In FIG. 4, a portion of the second ball 12 is also located radially inward from the third edge portion 20a.

[0049] Thus, in the angular ball bearing 1 of this embodiment, when the second retainer-attached ball 60 is placed in the second inner ring raceway groove 20, if the second minor angle θ2 is greater than 0° and less than the second angle K2, a portion of the second ball 12 that is located furthest vertically downward among the multiple second balls 12 is radially inward from the third edge portion 20a, and the second retainer 10 does not contact the inner ring 2. Furthermore, when the second minor angle θ2 is greater than or equal to the second angle K2, a portion of the second ball 12 located at the lowest vertical position is radially inward from the third edge portion 20a, and the second retainer 10 contacts the inner ring 2.

[0050] According to the above configuration, when the second retainer 10 is inclined relative to the inner ring 2 and the second minor angle θ2 becomes the second angle K2, the second retainer 10 is configured to come into contact with the inner ring 2, thereby preventing the second minor angle θ2 from becoming larger than the second angle K2. As a result, when the second ball and cage assembly 60 is placed on the inner ring 2 during assembly of the angular ball bearing 1, it is possible to prevent the second ball and cage assembly 60 from being unnecessarily tilted significantly relative to the inner ring 2, facilitating the subsequent attachment of the outer ring 4. As a result, the assembly work can be facilitated.

[0051] In addition, in the angular ball bearing 1 configured as described above, when the second minor angle θ2 is greater than or equal to 0° and less than the second angle K2, an axial gap is provided between the tip surface 40b1 (first surface) of the engagement portion 40b and the annular surface 18 of the inner ring 2, and when the second minor angle θ2 is greater than or equal to the second angle K2, the tip surface 40b1 and the annular surface 18 come into contact with each other. Therefore, contact between the tip surface 40b1 and the annular surface 18 can prevent the second minor angle θ2 from becoming larger than the second angle K2, and can prevent contact between the engagement portion 40b and the annular surface 18 when the central axis C2 of the second retainer coincides with the central axis C1 of the inner ring 2 in the angular ball bearing 1 after assembly work.

[0052] For example, as shown in Figure 6(a), when assembling a conventional angular ball bearing 200 in which the first retainer 204 of the first retainer-mounted ball 202 and the second retainer 208 of the second retainer-mounted ball 206 do not have an engagement portion, it was necessary to place a jig 220 outside the inner ring 210 and below the second retainer 208 to prevent the second retainer 208 from tilting. Furthermore, as shown in FIG. 6(b), when a conventional angular ball bearing 200 is mounted between a rotating shaft 300 and an axle box 302, it is sometimes not possible to use a jig such as that shown in FIG. 6(a).

[0053] However, as described above, the angular ball bearing 1 of this embodiment can prevent the first ball and cage assembly 50 and the second ball and cage assembly 60 from being unnecessarily tilted significantly relative to the inner ring 2 during assembly. Therefore, there is no need to use a jig as shown in Fig. 6(a), and assembly can be easily performed even when the bearing is mounted between the rotating shaft and the axle box as shown in Fig. 6(b).

[0054] 〔others〕 The embodiments disclosed herein are illustrative and not restrictive in all respects. The angular ball bearing 1 of the above embodiment is an angular ball bearing in which the second engagement portion 40b of the second small diameter annular body 40 (the first engagement portion 30b of the first small diameter annular body 30) is provided in an annular shape around the entire circumference of the annular main body portion 40a (annular main body portion 30a). However, the angular ball bearing of the present invention does not have to provide the second engagement portion 40b (first engagement portion 30b) annularly around the entire circumference of the second small-diameter annular body 40 (first small-diameter annular body 30). The angular ball bearing of the present invention may provide six second engagement portions 40b at equal intervals along the circumferential direction of the second small-diameter annular body 40, as shown in FIG. 7, for example. Furthermore, the angular ball bearing shown in FIG. 7 is an angular ball bearing in which six second engagement portions 40b are provided, but the angular ball bearing of the present invention may have a smaller number of second engagement portions 40b (first engagement portions 30b), for example, four or three, or a larger number, such as eight or nine. The angular ball bearing 1 of the above embodiment is a tandem double-row angular ball bearing having multiple ball rows. However, the angular ball bearing of the present invention may be an angular ball bearing having one ball row, or may be a double-row inward facing angular ball bearing. The first cage 6 and the second cage 10 of the angular ball bearing 1 in the above embodiment are squirrel cage cages. On the other hand, one or both of the first cage 6 and the second cage 10 of the angular ball bearing of the present invention may be a wave cage, a crown cage, a horn cage, a mating cage, or a split cage, as long as it can form a ball with cage configuration. The angular ball bearing 1 of the above embodiment has the first surface on the first engagement portion 30b of the first small diameter annular body 30. On the other hand, the angular ball bearing of the present invention may have the first surface by providing the first engagement portion on the first large diameter annular body 32. The angular ball bearing of the present invention may have the first engagement portion 30b on a horn or a post.

[0055] In addition, the angular ball bearing 1 in the above embodiment is exemplified as having a chamfered portion 32a on the first large diameter annular body 32, but if a sufficient distance can be secured between the first retainer 6 and the second retainer 10 and contact between the first retainer 6 and the second retainer 10 can be sufficiently avoided, it is not necessary to provide the first large diameter annular body 32 with the chamfered portion 32a.

[0056] The scope of the present invention is not limited to the above-described embodiment, but includes all modifications within the scope of the equivalents of the configurations described in the claims. [Explanation of symbols]

[0057] 1 angular contact ball bearing 2 inner ring 2a outer circumferential surface 2b Inner ring front 2c Inner ring back 4 Outer ring 4a Inner circumferential surface 6 First cage 8 1st ball 10 2nd cage 12 2nd ball 14: first inner ring raceway groove; 14a: first edge portion; 14b: second edge portion 16 first inner ring shoulder 18 annular surface 20 second inner ring raceway groove 20a third edge portion 20b fourth edge portion 22 second inner ring shoulder portion 24 first outer ring raceway groove 26 second outer ring raceway groove 30 first small diameter annular body 30a: Annular body portion; 30b: First engagement portion 30b1: tip surface (first surface) 32: first large diameter annular body 32a: chamfered portion 34 First pocket 34a Inner surface of first pocket 40: second small diameter annular body; 40a: annular main body portion; 40b: second engagement portion 40b1 tip surface (second surface) 42 second large diameter annular body 44 second pocket 44a Inner surface of second pocket 50 First ball with cage 60 No. 2 ball with cage C1 Center axis C2 Center axis C3 Center axis θ1 1st recessive angle θ2 2nd recessive angle

Claims

1. A double row angular contact ball bearing, The bearing comprises an inner ring, an outer ring, a first ball and cage assembly, a second cage, and a plurality of second balls, The first ball and cage assembly includes a first cage and a plurality of first balls, The inner ring is An inner ring front surface is provided on a first axial side, and an inner ring back surface is provided on a second axial side, a first inner ring raceway groove, a first inner ring shoulder, and a second inner ring raceway groove are provided on an outer periphery between the inner ring front surface and the inner ring back surface, from a first axial side to a second axial side, the first inner ring raceway groove and the first inner ring shoulder portion are connected to each other, The outer ring is a first outer ring raceway groove and a second outer ring raceway groove are provided on an inner circumference from a first axial side to a second axial side, the first cage includes a plurality of first posts, a first annular body, and a plurality of first pockets; the first pillars are connected to the first annular body at one of a first axial side of the first annular body and a second axial side of the first annular body; a space surrounded by two adjacent first pillars and the first annular body is a first pocket; Each of the first pockets has an inner surface that holds the first ball so that the first ball does not fall out of the first pocket, The first ball cage holds one first ball in each of a plurality of first pockets, the second retainer includes a plurality of second posts, a second annular body, and a plurality of second pockets; the second pillars are connected to the second annular body at one of a first axial side of the second annular body or a second axial side of the second annular body; a space surrounded by two adjacent second pillars and the second annular body is a second pocket; The second pockets each hold the second balls, a first inner ring raceway contact diameter of the first inner ring raceway groove is smaller than a second inner ring raceway contact diameter of the second inner ring raceway groove; a first outer ring raceway contact diameter of the first outer ring raceway groove is smaller than a second outer ring raceway contact diameter of the second outer ring raceway groove; When the inner ring is disposed with the inner ring back surface facing downward in the vertical direction and the first ball cage is placed in the first inner ring raceway groove from a first axial side, when a first minor angle formed between a central axis of the first cage and a central axis of the inner ring is equal to or greater than 0° and less than a first angle, a part of a first ball that is located at the lowermost position in the vertical direction among the plurality of first balls is located radially inward of the first edge portion, and the first cage does not contact the inner ring, When the first minor angle is equal to or larger than the first angle, a portion of the first ball located at the lowermost position in the vertical direction is located radially inward of the first edge portion, and the first cage contacts the inner ring. Double row angular contact ball bearing.

2. a second edge portion of the first inner ring raceway groove on a first side in the axial direction is connected to a front surface of the inner ring, the first cage has a first surface facing the front surface of the inner ring, When the first minor angle is equal to or greater than 0° and less than the first angle, an axial gap is provided between the first surface and the inner ring front surface, When the first minor angle is equal to or greater than the first angle, the first surface and the inner ring front surface come into contact with each other.

2. A double row angular contact ball bearing according to claim 1.

3. the first annular body is a first small-diameter annular body connected to a first axial side of the plurality of columns, The first small diameter annular body is An annular body portion; a first engagement portion protruding from the annular main body portion toward a front surface of the inner ring, The first surface is provided at a tip of the first engagement portion.

3. A double row angular contact ball bearing according to claim 2.

4. The first cage further includes a first large diameter annular body, The first large-diameter annular body has an end face on a second axial side thereof having a chamfered portion that defines a gap between the first large-diameter annular body and the second cage. The double row angular contact ball bearing according to any one of claims 1 to 3.

5. A double row angular contact ball bearing, the bearing comprises an inner ring, an outer ring, a first cage disposed between the inner ring and the outer ring, a plurality of first balls held by the first cage, the first cage, the plurality of first balls, and two balls with a second cage; The second ball and cage assembly includes a second cage and a plurality of second balls, The inner ring is An inner ring front surface is provided on a first axial side, and an inner ring back surface is provided on a second axial side, a first inner ring raceway groove, a second inner ring raceway groove, and a second inner ring shoulder are provided on an outer periphery between the inner ring front surface and the inner ring back surface, from a first axial side to a second axial side, the second inner ring raceway groove and the second inner ring shoulder portion are connected to each other, The outer ring is a first outer ring raceway groove and a second outer ring raceway groove are provided on an inner circumference from a first axial side to a second axial side, the first cage includes a plurality of first posts, a first annular body, and a plurality of first pockets; the first pillars are connected to the first annular body at one of a first axial side of the first annular body and a second axial side of the first annular body; a space surrounded by two adjacent first pillars and the first annular body is a first pocket; The first pockets each hold the first balls, the second retainer includes a plurality of second posts, a second annular body, and a plurality of second pockets; the second pillars are connected to the second annular body at one of a first axial side of the second annular body or a second axial side of the second annular body; a space surrounded by two adjacent second pillars and the second annular body is a second pocket; each of the second pockets has an inner surface that holds the second ball so that the second ball does not fall out of the first pocket; The second ball cage holds one second ball in each of a plurality of second pockets, a first inner ring raceway contact diameter of the first inner ring raceway groove is smaller than a second inner ring raceway contact diameter of the second inner ring raceway groove; a first outer ring raceway contact diameter of the first outer ring raceway groove is smaller than a second outer ring raceway contact diameter of the second outer ring raceway groove; When the inner ring is disposed with the inner ring back surface facing downward in the vertical direction and the second ball cage is placed in the second inner ring raceway groove from the first axial side, when a second minor angle formed between a central axis of the second cage and a central axis of the inner ring is equal to or greater than 0° and less than a second angle, a part of the second balls that is located at the lowermost position in the vertical direction among the plurality of second balls is located radially inward of the third edge portion, and the second cage does not contact the inner ring, When the second minor angle is equal to or larger than the second angle, a part of the second ball located at the lowermost position in the vertical direction is located radially inward of the third edge portion, and the second cage contacts the inner ring. Double row angular contact ball bearing.

6. the inner ring further has an annular surface facing a first side in the axial direction between the first inner ring raceway groove and the second inner ring raceway groove, a fourth edge portion of the second inner ring raceway groove on a first side in the axial direction is connected to the annular surface, the second retainer has a second surface opposing the annular surface; When the second minor angle is equal to or greater than 0° and less than the second angle, an axial gap is provided between the second surface and the annular surface, When the second minor angle is equal to or greater than a second angle, the second surface and the annular surface are in contact with each other.

6. A double row angular contact ball bearing according to claim 5.

7. An angular contact ball bearing, The inner ring, the outer ring, A ball with a cage; The ball and cage assembly includes a cage and a plurality of balls, The inner ring is An inner ring front surface is provided on a first axial side, and an inner ring back surface is provided on a second axial side, an inner ring raceway groove and an inner ring shoulder are provided on an outer periphery between the inner ring front surface and the inner ring back surface from a first axial side to a second axial side, the inner ring raceway groove and the inner ring shoulder portion are connected, The outer ring is an outer ring raceway groove is provided on an inner circumference from a first axial side to a second axial side; the retainer comprises a plurality of posts, an annulus, and a plurality of pockets; the plurality of posts are connected to the annular body at one of a first axial side of the annular body or a second axial side of the annular body; A space surrounded by two adjacent pillars and the annular body is a pocket, Each of the plurality of pockets has an inner surface that holds the ball so that the ball does not fall out of the pocket; The ball cage holds one ball in each of a plurality of pockets, When the inner ring is disposed with the inner ring back surface facing downward in the vertical direction and the ball with cage is placed on the inner ring raceway groove from a first axial side, When a minor angle between a central axis of the cage and a central axis of the inner ring is equal to or greater than 0° and less than a first angle, a part of the balls located at the lowermost position in the vertical direction among the plurality of balls is located radially inward of the first edge portion, and the cage does not contact the inner ring, When the minor angle is equal to or larger than the first angle, a part of the ball located at the lowermost position in the vertical direction is located radially inward of the first edge portion, and the cage contacts the inner ring. Angular contact ball bearing.

8. a second edge portion of the inner ring raceway groove on a first side in the axial direction is connected to a front surface of the inner ring, The cage has a first surface facing the front surface of the inner ring, When the minor angle is equal to or greater than 0° and less than the first angle, an axial gap is provided between the first surface and the inner ring front surface, When the minor angle is equal to or larger than the first angle, the first surface and the inner ring front surface come into contact with each other.

8. The angular contact ball bearing according to claim 7.

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