WO2023135667A1 - Ball bearing - Google Patents

Ball bearing Download PDF

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Publication number
WO2023135667A1
WO2023135667A1 PCT/JP2022/000639 JP2022000639W WO2023135667A1 WO 2023135667 A1 WO2023135667 A1 WO 2023135667A1 JP 2022000639 W JP2022000639 W JP 2022000639W WO 2023135667 A1 WO2023135667 A1 WO 2023135667A1
Authority
WO
WIPO (PCT)
Prior art keywords
outer ring
balls
inner ring
raceway
diameter
Prior art date
Application number
PCT/JP2022/000639
Other languages
French (fr)
Japanese (ja)
Inventor
清兼 岩本
勇泰 久保山
知博 石井
Original Assignee
株式会社ジェイテクト
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社ジェイテクト filed Critical 株式会社ジェイテクト
Priority to PCT/JP2022/000639 priority Critical patent/WO2023135667A1/en
Publication of WO2023135667A1 publication Critical patent/WO2023135667A1/en

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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C19/00—Bearings with rolling contact, for exclusively rotary movement
    • F16C19/02—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows
    • F16C19/14—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load
    • F16C19/18—Bearings with rolling contact, for exclusively rotary movement with bearing balls essentially of the same size in one or more circular rows for both radial and axial load with two or more rows of balls
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/30—Parts of ball or roller bearings
    • F16C33/32—Balls
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C33/00—Parts of bearings; Special methods for making bearings or parts thereof
    • F16C33/30—Parts of ball or roller bearings
    • F16C33/58—Raceways; Race rings
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
    • F16C43/00—Assembling bearings
    • F16C43/04—Assembling rolling-contact bearings

Definitions

  • This disclosure relates to ball bearings.
  • angular contact ball bearings of double-row ball bearings have the minor angle between the bearing central axis and the line of action of each row of balls arranged in the same direction, and the pitch diameter of the ball set of each row of balls is made different, and the single-row A ball bearing is known that can bear a greater axial load than an angular contact ball bearing.
  • Such ball bearings are called tandem type.
  • FIG. 13 is a sectional view showing a conventional ball bearing.
  • a conventional ball bearing 210 comprises an inner ring assembly 235 and an outer ring 220 .
  • the inner ring assembly 235 includes an inner ring 230 , a plurality of first balls 241 , a plurality of second balls 242 , a first retainer 251 and a second retainer 252 .
  • the diameter of the plurality of first balls 241 and the diameter of the plurality of second balls 242 are the same.
  • the inner ring 230 has a first inner ring raceway 231 on the first side in the axial direction and a second inner ring raceway 232 on the second side in the axial direction of the first inner ring raceway 231 on the outer peripheral surface.
  • the raceway contact diameter of the first inner ring raceway 231 is smaller than the raceway contact diameter of the second inner ring raceway 232 .
  • a plurality of first balls 241 are arranged to roll on the first inner ring raceway 231 .
  • the first retainer 251 has multiple pockets.
  • a plurality of first balls 241 are slidably disposed in a plurality of pockets of the first retainer 251 . Since the diameter of the inscribed circle of the radially outer openings of the plurality of pockets of the first retainer 251 is smaller than the diameter of the first balls 241, the plurality of first balls 241 are each held in the first holding state.
  • the inner ring 230, the plurality of first balls 241 and the first retainer 251 are not separated.
  • a plurality of second balls 242 are arranged to roll on the second inner ring raceway 232 .
  • the second retainer 252 has multiple pockets.
  • a plurality of second balls 242 are slidably disposed in a plurality of pockets of the second retainer 252 . Since the diameter of the inscribed circle of the radially outer openings of the plurality of pockets of the second retainer 252 is smaller than the diameter of the second balls 242, the plurality of second balls 242 are each held in the second holding state.
  • the inner ring 230, the plurality of second balls 242, and the second retainer 252 do not separate when placed in each pocket of the container 252 and placed on the second inner ring raceway 232.
  • the inner ring assembly 235 is assembled so that the inner ring 230, the plurality of first balls 241, the plurality of second balls 242, the first retainer 251, and the second retainer 252 are not separated. It is
  • the pitch diameter of the ball set in the row of the first balls 241 formed by the plurality of first balls 241 of the inner ring assembly 235 is the same as the pitch diameter of the balls in the row of the second balls 242 formed by the plurality of second balls 242. Smaller than the pitch diameter of the set.
  • the outer ring 220 has a first outer ring raceway 221 on the first side in the axial direction and a second outer ring raceway 222 on the second side in the axial direction of the first outer ring raceway 221 on its inner peripheral surface.
  • the raceway contact diameter of the first outer ring raceway 221 is smaller than the raceway contact diameter of the second outer ring raceway 222 .
  • Ball bearing 210 is formed by combining inner ring assembly 235 and outer ring 220 .
  • the plurality of first balls 241 are rollably arranged on the first outer ring raceway 221, and the plurality of second balls 242 are rollably arranged on the second outer ring raceway 222.
  • the nominal contact point of the first inner ring raceway 231 is located on the second axial side of the nominal contact point of the first outer ring raceway 221 .
  • the nominal contact point of the second inner ring raceway 232 is located on the second axial side of the nominal contact point of the second outer ring raceway 222 .
  • the side surface on the first axial side of the inner ring 230 is the front surface of the inner ring 230
  • the side surface on the second axial side is the rear surface of the inner ring 230 .
  • the side surface of the outer ring 220 on the first side in the axial direction is the rear surface of the outer ring 220
  • the side surface on the second side in the axial direction is the front surface of the outer ring 220 . Since the ball bearing 210 has two rows of balls, the axial load that the ball bearing 210 can bear is larger than the axial load that a single-row angular contact ball bearing can bear (see, for example, Patent Document 1).
  • the diameter of the first ball 241 and the diameter of the second ball 242 are the same.
  • the life of the first row of balls 241, the first inner ring raceway 231, and the first outer ring raceway 221, the life of the second row of balls 242, the second inner ring raceway 232, and the second outer ring raceway 222 It may be greatly different from the life related to.
  • a ball bearing of the present disclosure comprises an inner ring assembly, an outer ring, the inner ring assembly comprising an inner ring, a plurality of first balls, a plurality of second balls, a first cage, and a second retainer, the inner ring having a first inner ring raceway on a first axial side and a second inner ring raceway on a second axial side of the first inner ring raceway; , on the outer peripheral surface, the raceway contact diameter of the first inner ring raceway is smaller than the raceway contact diameter of the second inner ring raceway, and the plurality of first balls are arranged on the first inner ring raceway.
  • the first retainer has a plurality of first pockets, the plurality of first balls are slidably arranged in the first pockets, the plurality of A second ball is rotatably disposed on the second inner ring raceway, the second retainer has a plurality of second pockets, the plurality of second balls are arranged in the second The inner ring, the plurality of first balls, the plurality of second balls, the first retainer, and the second retainer are separated from each other. and the pitch diameter of the ball set in the first row of balls formed by the plurality of first balls of the inner ring assembly is equal to the pitch diameter of the second ball formed by the plurality of second balls.
  • the outer ring has a first outer ring raceway, a first inclined surface and a second having an inclined surface and a second outer ring raceway on the inner peripheral surface, the inner peripheral surface of the outer ring expanding without decreasing in diameter from the first outer ring raceway to the second outer ring raceway;
  • the raceway contact diameter of the first outer ring raceway is smaller than the raceway contact diameter of the second outer ring raceway, the diameter of the plurality of first balls is smaller than the diameter of the plurality of second balls;
  • the plurality of first balls are rollably arranged on the first outer ring raceway, the plurality of second balls are rollably arranged on the second outer ring raceway, and the first ball is arranged to roll on the second outer ring raceway.
  • the nominal contact point of the inner ring raceway is located on the second side in the axial direction from the nominal contact point of the first outer ring raceway, and the nominal contact point of the second inner ring raceway is the nominal contact point of the second outer ring raceway.
  • the first inclined surface is formed on the second side in the axial direction of the first outer ring raceway on the inner peripheral surface of the outer ring. It is an inclined surface that expands in diameter from a first side toward a second side, and the second inclined surface is on the second side in the axial direction of the first inclined surface on the inner peripheral surface of the outer ring.
  • a first minor angle formed by the first inclined surface and the central axis of the outer ring in a cross section is equal to a second minor angle formed by the second inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring.
  • a first minor radius which is the radius of the first minor circle, is half the diameter of the first ball on the great circle, and half the pitch diameter of the ball set in the first row of balls is the first minor radius.
  • a torus with a first major radius that is the radius of one great circle is defined as a first virtual torus, and when the plurality of second balls are arranged and brought into contact with the second inner ring raceway, the The center of each second ball of the plurality of second balls is on the second great circle, and half the diameter of the second ball is the second minor radius, which is the radius of the second small circle;
  • a second virtual torus is defined as a torus having a second major radius, which is the radius of the second great circle, which is half the pitch diameter of the ball set of the second row of balls, and includes the bearing center axis.
  • a radial first side and a radial second side that is 180° circumferentially opposite the radial first side are defined, and the radial second side
  • a second end point is defined as an intersection point of the first virtual torus on the first side with the surface of the first side in the radial direction, and a line segment connecting the first end point and the second end point is defined as the first end point.
  • a line segment a line segment connecting the first end point and the third end point, with a third end point on the second side in the axial direction of the first inclined surface on the first side in the radial direction; is a second line segment, a point on the first inclined surface on the first side in the radial direction and the shortest distance from the first end point is the fourth end point, and the first end point and the A line segment connecting the fourth end point is defined as a third line segment, and the length of the first line segment is greater than the length of the second line segment, or the length of the first line segment is is smaller than the length of the second line segment and smaller than the length of the third line segment.
  • the outer ring has the first outer ring raceway, the first inclined surface, and the second radial direction on the inner peripheral surface from the first side in the axial direction toward the second side. , the second outer ring raceway, and a third inclined surface, and the inner peripheral surface of the outer ring is reduced in diameter from the first outer ring raceway to the third inclined surface.
  • the first minor angle is smaller than the third minor angle formed by the third inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring.
  • the plurality of second balls and an imaginary plane including the front surface of the second axial side of the outer ring and perpendicular to the central axis of the outer ring overlap in the axial direction.
  • FIG. 3 is a schematic diagram showing an outline of a first virtual torus and a second virtual torus; It is a sectional view showing an outer race concerning a 1st embodiment.
  • FIG. 4 is a cross-sectional view showing each inclined surface formed on the inner peripheral surface of the outer ring;
  • FIG. 3 is a cross-sectional view showing how the outer ring is assembled to the inner ring assembly of the ball bearing according to the first embodiment;
  • FIG. 3 is a schematic diagram showing an outline of a first virtual torus and a second virtual torus; It is a sectional view showing an outer race concerning a 1st embodiment.
  • FIG. 4 is a cross-sectional view showing each inclined surface formed on the inner peripheral surface of the outer ring;
  • FIG. 3 is a cross-sectional view showing how the outer ring is assembled to the inner ring assembly
  • FIG. 7 is a cross-sectional view showing how the outer ring is assembled to the inner ring assembly of the ball bearing according to the second embodiment; It is a sectional view showing the whole ball bearing composition concerning a comparative example.
  • FIG. 3 is a cross-sectional view showing an outer ring according to a comparative example;
  • FIG. 5 is a cross-sectional view showing how an outer ring is attached to an inner ring assembly of a ball bearing according to a comparative example;
  • FIG. 10 is a cross-sectional view showing a conventional ball bearing;
  • FIG. 4 is a cross-sectional view showing how an outer ring is attached to an inner ring assembly in a ball bearing of a comparative example;
  • FIG. 14 is a cross-sectional view showing how the outer ring is attached to the inner ring assembly in the ball bearing of the comparative example.
  • the second balls 242 of the conventional double-row ball bearing 210 shown in FIG. It is a configuration that converts A double-row ball bearing 110 of the comparative example includes an inner ring assembly 135 and an outer ring 120 .
  • the inner ring assembly 135 includes an inner ring 130 , a plurality of first balls 141 , a plurality of second balls 142 , a first retainer 151 and a second retainer 152 .
  • the inner ring 130 has a first inner ring raceway 131 on the first side in the axial direction and a second inner ring raceway 132 on the second side in the axial direction of the first inner ring raceway 131 on the outer peripheral surface.
  • the raceway contact diameter of the first inner ring raceway 131 is smaller than the raceway contact diameter of the second inner ring raceway 132 .
  • a plurality of first balls 141 are arranged to roll on the first inner ring raceway 131 .
  • the first retainer 151 has multiple pockets. The plurality of first balls 141 are slidably arranged in the plurality of pockets of the first retainer 151 .
  • the plurality of first balls 141 are respectively attached to the first retainer. 151 and placed on the first inner ring raceway 131, the inner ring 130, the plurality of first balls 141 and the first retainer 151 are not separated.
  • a plurality of second balls 142 are arranged to roll on the second inner ring raceway 132 .
  • the second retainer 152 has multiple pockets.
  • a plurality of second balls 142 are slidably disposed in a plurality of pockets of the second retainer 152 .
  • the plurality of second balls 142 are respectively attached to the second retainer.
  • the inner ring 130, the plurality of second balls 142 and the second retainer 152 do not separate.
  • the inner ring 130, the plurality of first balls 141, the plurality of second balls 142, the first retainer 151, and the second retainer 152 are configured so as not to separate.
  • the pitch diameter of the ball set in the row of the first balls 141 formed by the plurality of first balls 141 of the inner ring assembly 135 is the same as the pitch diameter of the balls in the row of the second balls 142 formed by the plurality of second balls 142. Smaller than the pitch diameter of the set.
  • the diameter of the plurality of first balls 141 is smaller than the diameter of the plurality of second balls 142 .
  • the outer ring 120 has a first outer ring raceway 121, a first inclined surface 123, a second inclined surface 124, and a second outer ring raceway 122 from the first side in the axial direction to the second side. and a third inclined surface 125 on the inner peripheral surface.
  • the inner peripheral surface of the outer ring 120 expands from the first outer ring raceway 121 to the third inclined surface 125 without decreasing in diameter.
  • the raceway contact diameter of the first outer ring raceway 121 is smaller than the raceway contact diameter of the second outer ring raceway 122 .
  • Ball bearing 110 is formed by combining inner ring assembly 135 and outer ring 120 .
  • a plurality of first balls 141 are arranged to roll on the first outer ring raceway 121 .
  • a plurality of second balls 142 are arranged to roll on the second outer ring raceway 122 .
  • the nominal contact point of the first inner ring raceway 131 is located on the second axial side of the nominal contact point of the first outer ring raceway 121 .
  • the nominal contact point of the second inner ring raceway 132 is located on the second axial side of the nominal contact point of the second outer ring raceway 122 .
  • the first inclined surface 123 is formed on the inner peripheral surface of the outer ring 120 on the second side in the axial direction of the first outer ring raceway 121 and has a diameter that increases from the first side in the axial direction toward the second side. It is a conical surface that
  • the second inclined surface 124 is formed on the second axial side of the first inclined surface 123 on the inner peripheral surface of the outer ring 120 and on the first axial side of the second outer ring raceway 122, It is a conical surface that expands in diameter from a first axial side toward a second axial side.
  • a third inclined surface 125 is formed on the inner peripheral surface of the outer ring 120 on the axial second side of the second outer ring raceway 122 , adjoins the front surface of the outer ring 120 , and extends from the axial first side to the third axial side. It is a conical surface that expands toward the side of 2.
  • An object of the present disclosure is to improve the assembling property of the outer ring to the inner ring assembly and to suppress damage to the ball bearing in the ball bearing.
  • a ball bearing of the present disclosure comprises an inner ring assembly and an outer ring, the inner ring assembly comprising an inner ring, a plurality of first balls, a plurality of second balls, and a first retainer. and a second retainer, wherein the inner ring has a first inner ring raceway on a first axial side and a second inner ring raceway on a second axial side of the first inner ring raceway.
  • the raceway contact diameter of the first inner ring raceway being smaller than the raceway contact diameter of the second inner ring raceway, and the plurality of first balls rollingly disposed on an inner ring raceway
  • the first retainer having a plurality of first pockets, the plurality of first balls slidably disposed in the first pockets;
  • the plurality of second balls are arranged to be able to roll on the second inner ring raceway, the second retainer has a plurality of second pockets, and the plurality of second balls are: slidably disposed in the second pocket, the inner ring, the plurality of first balls, the plurality of second balls, the first retainer, and the second retainer; are configured not to separate, and the pitch diameter of the ball set in the first row of balls formed by the plurality of first balls of the inner ring assembly is equal to the pitch diameter of the ball set formed by the plurality of second balls.
  • the outer ring has, from the first side in the axial direction toward the second side, a first outer ring raceway, a first inclined surface;
  • the inner peripheral surface of the outer ring has a second inclined surface and a second outer ring raceway, and the inner peripheral surface of the outer ring does not decrease in diameter from the first outer ring raceway to the second outer ring raceway.
  • the raceway contact diameter of the first outer ring raceway is smaller than the raceway contact diameter of the second outer ring raceway, and the diameter of the plurality of first balls is smaller than the diameter of the plurality of second balls.
  • the plurality of first balls are arranged so as to be able to roll on the first outer ring raceway; the plurality of second balls are arranged so as to be able to roll on the second outer ring raceway;
  • the nominal contact point of the first inner ring raceway is located on the second side in the axial direction from the nominal contact point of the first outer ring raceway, and the nominal contact point of the second inner ring raceway is located on the second outer ring.
  • the first inclined surface being formed on the second side in the axial direction of the first outer ring raceway on the inner peripheral surface of the outer ring, It is an inclined surface that expands in diameter from a first side toward a second side in the axial direction, and the second inclined surface is the second inclined surface in the axial direction of the first inclined surface on the inner peripheral surface of the outer ring.
  • a first minor angle formed by the first inclined surface and the central axis of the outer ring in a cross section containing the axis is equal to a first minor angle formed by the second inclined surface and the central axis of the outer ring in a cross section containing the central axis of the outer ring.
  • the center of each first ball of the plurality of first balls is smaller than the second minor angle formed and when the plurality of first balls are arranged on the first inner ring raceway and brought into contact with each other.
  • half the diameter of the first ball is the radius of the first minor circle, the first minor radius being the radius of the first minor circle, and half the pitch diameter of the ball set of the first row of balls.
  • the radius of the first great circle is the radius of the first great circle
  • the torus is defined as the first virtual torus
  • the plurality of second balls are arranged and brought into contact with the second inner ring raceway
  • the center of each second ball of said plurality of second balls is on a second great circle
  • half the diameter of said second ball is the radius of a second minor circle.
  • a second virtual torus is defined as a torus having a radius and a half of the pitch diameter of the ball set of the second ball row as the second major radius, which is the radius of the second great circle, and the bearing center
  • a radial first side and a radial second side that is 180° circumferentially opposite the radial first side are defined, and a radial second side
  • the outer ring has the first outer ring raceway and the first inclined surface extending from the first side in the axial direction to the second side on the inner peripheral surface.
  • the second inclined surface, the second outer ring raceway, and a third inclined surface, and the inner peripheral surface of the outer ring extends from the first outer ring raceway to the third inclined surface.
  • the diameter is enlarged without being reduced, and the first minor angle is smaller than the third minor angle formed by the third inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring.
  • FIG. 1 is a cross-sectional view showing the overall configuration of a ball bearing according to the first embodiment.
  • the ball bearing 10 shown in FIG. 1 is a double-row angular contact ball bearing in which the minor angles between the bearing central axis and the line of action of each row of balls are set in the same direction, and the pitches of the ball sets of each row of balls are equal to each other.
  • This is a ball bearing with different diameters that can handle a greater axial load than a single-row angular contact ball bearing.
  • Such ball bearings are called tandem type.
  • the ball bearing 10 is used, for example, to rotatably support a pinion shaft constituting a differential mechanism (gear mechanism), which is a bearing device used in a differential gear device mounted on an automobile or the like, with respect to a case. .
  • the ball bearing 10 has an inner ring assembly 35 and an outer ring 20 .
  • the central axis of the ball bearing 10 will be referred to as central axis C1.
  • the central axis of the outer ring 20 is called central axis C2
  • the central axis of the inner ring 30 is called central axis C3.
  • the central axis C2 of the outer ring 20 and the central axis C3 of the inner ring 30 coincide with the central axis C1 of the ball bearing 10 in which the inner ring assembly 35 and the outer ring 20 are combined.
  • one direction along the central axis C1 of the ball bearing 10 is referred to as a first axial side, and is 180° opposite to the first axial side along the central axis of the ball bearing 10.
  • the side direction is referred to as the axial second side.
  • one direction perpendicular to the central axis C1 is referred to as a radial first side.
  • the direction 180° opposite to the side of is referred to as a second side in the radial direction.
  • FIG. 2 is a cross-sectional view showing the inner ring assembly.
  • the inner ring assembly 35 includes an inner ring 30 , a plurality of first balls 41 , a plurality of second balls 42 , a first retainer 51 and a second retainer 52 .
  • the inner ring 30 shown in FIG. 2 is made of steel such as high-carbon chromium bearing steel, carbon steel, or alloy steel.
  • the inner ring 30 is cylindrical.
  • the inner ring 30 has a first shoulder, a first inner ring raceway 31, a second shoulder, a second inner ring raceway 32, a third inner ring raceway 32, and a third inner ring raceway 31 from the first side in the axial direction toward the second side. and a shoulder on the outer peripheral surface.
  • the first shoulder has a cylindrical outer peripheral surface.
  • the first inner ring raceway 31 is a raceway groove having a groove radius slightly larger than half the diameter of a first ball 41 to be described later.
  • the second shoulder is a conical surface followed by a cylindrical surface whose outer peripheral surface increases in diameter from the first axial side to the second axial side.
  • the second inner ring raceway 32 is a raceway groove having a groove radius slightly larger than half the diameter of a second ball 42 to be described later.
  • the third shoulder has a cylindrical outer peripheral surface.
  • the raceway contact diameter of the first inner ring raceway 31 is smaller than the raceway contact diameter of the second inner ring raceway 32 .
  • the diameter of the first shoulder is larger than the raceway contact diameter of the first inner ring raceway 31 and smaller than the diameter of the second shoulder.
  • the diameter of the second shoulder is larger than the diameter of the second inner ring raceway 32 and smaller than the diameter of the third shoulder.
  • the first ball 41 is made of steel such as high carbon chromium bearing steel.
  • the second ball 42 is made of steel such as high carbon chromium bearing steel.
  • the diameter of the first ball 41 is smaller than the diameter of the second ball 42 .
  • the first retainer 51 is formed in an annular shape.
  • the first retainer 51 has a first annular body 51a, a second annular body 51b, and a plurality of first pillars 51c.
  • the first annular body 51a is on the first axial side of the plurality of first posts 51c.
  • the second annular body 51b is on the second axial side of the plurality of first posts 51c.
  • a plurality of first posts 51c connect to the first annular body 51a on a second axial side of the first annular body 51a.
  • a plurality of first posts 51c connect to the second annular body 51b on a first axial side of the second annular body 51b.
  • the plurality of first columns 51c are arranged at regular intervals in the circumferential direction of the first annular body 51a.
  • the diameter of the outer peripheral surface of the first annular body 51a is smaller than the diameter of the outer peripheral surface of the second annular body 51b.
  • the diameter of the inner peripheral surface of the first annular body 51a is smaller than the diameter of the inner peripheral surface of the second annular body 51b.
  • a region surrounded by the first annular body 51a, the second annular body 51b, and the first pillars 51c adjacent in the circumferential direction forms a plurality of first pockets 53 that hold the first balls 41. do.
  • the diameter of the inscribed circle of the radially outer openings of the plurality of first pockets 53 of the first retainer 51 is smaller than the diameter of the first balls 41 .
  • the first retainer 51 is made of synthetic resin such as polyamide resin, polyphenylene sulfide resin, or phenol resin.
  • the second retainer 52 is formed in an annular shape.
  • the second retainer 52 has a third annular body 52b, a fourth annular body 52a, and a plurality of second posts 52c.
  • the third annular body 52b is on the first axial side of the plurality of second posts 52c.
  • the fourth annular body 52a is on the second axial side of the plurality of second posts 52c.
  • a plurality of second posts 52c connect to the third annular body 52b on a second axial side of the third annular body 52b.
  • a plurality of second posts 52c connect to the fourth annular body 52a on a first axial side of the fourth annular body 52a.
  • the plurality of second columns 52c are arranged at regular intervals in the circumferential direction of the third annular body 52b.
  • the diameter of the outer peripheral surface of the third annular body 52b is smaller than the diameter of the outer peripheral surface of the fourth annular body 52a.
  • the diameter of the inner peripheral surface of the third annular body 52b is smaller than the diameter of the inner peripheral surface of the fourth annular body 52a.
  • a region surrounded by the third annular body 52b, the fourth annular body 52a, and the second pillars 52c adjacent in the circumferential direction forms a plurality of second pockets 54 that hold the second balls 42. do.
  • the diameter of the inscribed circle of the radially outer openings of the plurality of second pockets 54 of the second retainer 52 is smaller than the diameter of the second balls 42 .
  • the second retainer 52 is made of synthetic resin such as polyamide resin, polyphenylene sulfide resin, or phenol resin.
  • the plurality of first balls 41 forming the row of the first balls 41 are arranged to roll on the first inner ring raceway 31 of the inner ring 30 .
  • the plurality of first balls 41 are slidably arranged in the plurality of first pockets 53 of the first retainer 51 .
  • a plurality of first pockets 53 are formed along the circumferential direction so that the first retainer 51 can hold the plurality of first balls 41 at regular intervals along the circumferential direction. . Since the diameter of the inscribed circle of the radially outer openings of the plurality of first pockets 53 of the first retainer 51 is smaller than the diameter of the first balls 41, the first balls 41 do not drop radially outward from the first pocket 53 of the retainer 51 of the .
  • the diameter of the cylindrical surface of the outer peripheral surface of the first shoulder is larger than the raceway contact diameter of the first inner ring raceway 31 .
  • the minimum diameter of the conical surface of the outer peripheral surface of the second shoulder is larger than the raceway contact diameter of the first inner ring raceway 31 . Therefore, when the plurality of first balls 41 are arranged in the respective first pockets 53 of the first retainer 51 and arranged on the first inner ring raceway 31, the inner ring 30 and the plurality of first balls 41 and the first retainer 51 are not separated.
  • a plurality of second balls 42 forming a row of second balls 42 are arranged to roll on the second inner ring raceway 32 of the inner ring 30 .
  • a plurality of second balls 42 are slidably disposed in a plurality of second pockets 54 of the second retainer 52 .
  • a plurality of second pockets 54 are formed along the circumferential direction so that the second retainer 52 can hold the plurality of second balls 42 at regular intervals along the circumferential direction. . Since the diameter of the inscribed circle of the radially outer openings of the plurality of second pockets 54 of the second retainer 52 is smaller than the diameter of the second balls 42, the second balls 42 from the second pocket 54 of the retainer 52 in the radial direction.
  • the diameter of the cylindrical surface of the outer peripheral surface of the second shoulder is larger than the raceway contact diameter of the second inner ring raceway 32 .
  • the diameter of the cylindrical surface of the outer peripheral surface of the third shoulder is larger than the raceway contact diameter of the second inner ring raceway 32 . Therefore, when the plurality of second balls 42 are arranged in the respective second pockets 54 of the second retainer 52 and arranged on the second inner ring raceway 32, the inner ring 30 and the plurality of second balls 42 and the second retainer 52 are not separated.
  • the inner ring assembly 35 includes an inner ring 30, a plurality of first balls 41, a plurality of second balls 42, a first retainer 51, and a second retainer 52. , are configured so that they do not separate. In other words, the inner ring assembly 35 is obtained by removing the outer ring 20 from the ball bearing 10 .
  • the pitch diameter of the ball set in the row of the first balls 41 formed by the plurality of first balls 41 of the inner ring assembly 35 is the same as the pitch diameter of the balls in the row of the second balls 42 formed by the plurality of second balls 42. Smaller than the pitch diameter of the set.
  • the first virtual torus T1 is a virtual three-dimensional shape that represents the rolling area of the plurality of first balls 41 that are rotatably arranged on the first inner ring raceway 31 .
  • the first virtual torus T1 is the position of each first ball 41 when each first ball 41 is arranged and contacted with the first inner ring raceway 31 when the inner ring assembly 35 and the outer ring 20 are assembled.
  • the radius of the first small circle SC1, which is the outer shape of the cross section including the center, is defined as the first small radius Sr1
  • the radius of the first large circle BC1 which is the imaginary circle connecting the centers of the first balls 41
  • the first small radius Sr1 is the radius of the first balls 41 and is half the diameter of the first balls 41
  • the first large radius Br1 is composed of the plurality of first balls 41. It is half the pitch diameter of the set of balls in the row of the first balls 41 that are set.
  • the center of each first ball 41 of the plurality of first balls 41 is positioned on the first great circle BC1.
  • the first virtual torus T1 is defined with reference to the first balls 41 arranged on the first inner ring raceway 31, but the first virtual torus T1 is the inner ring assembly 35 and The first balls 41 when the first balls 41 are arranged and contacted with the first outer ring raceway 21 when the outer ring 20 is assembled may be defined as a reference.
  • the second virtual torus T2 is a virtual three-dimensional shape that represents the rolling area of the plurality of second balls 42 that are rollably arranged on the second inner ring raceway 32 .
  • the second virtual torus T2 is the position of each second ball 42 when each second ball 42 is arranged and comes into contact with the second inner ring raceway 32 when the inner ring assembly 35 and the outer ring 20 are assembled.
  • the radius of the second small circle SC2, which is the outer shape of the cross section including the center, is defined as the second small radius Sr2
  • the radius of the second large circle BC2 which is the imaginary circle connecting the centers of the second balls 42, is defined as the second small radius Sr2.
  • the second minor radius Sr2 is the radius of the second balls 42 and is half the diameter of the second balls 42
  • the second major radius Br2 is composed of the plurality of second balls 42. It is half the pitch diameter of the set of balls in the second row of balls 42 being set.
  • the center of each second ball 42 of the plurality of second balls 42 is positioned on the second great circle BC2.
  • the second virtual torus T2 is defined with reference to the second balls 42 arranged on the second inner ring raceway 32.
  • the second virtual torus T2 is the inner ring assembly 35.
  • the second balls 42 may be defined as a reference when the second balls 42 are arranged and contacted with the second outer ring raceway 22 when the outer ring 20 is assembled.
  • a first straight line L1 is defined for convenience of explanation.
  • the first straight line L1 extends across the central axis C3, the first great circle BC1 on the first radial side, and the second great circle BC1 on the second radial side in a cross section including the central axis C3 of the inner ring 30. It is a straight line that intersects with the great circle BC2.
  • the first radial side is one radial direction in a cross section including the central axis C3 of the inner ring 30, and the second radial side is the second radial direction in a cross section including the central axis C3 of the inner ring 30.
  • the 1 side is the radial direction opposite to the center axis C3 of the inner ring 30 by 180° in the circumferential direction.
  • a point a (first end point) is the intersection of the first straight line L1 and the second great circle BC2 on the second side in the radial direction in a cross section including the center axis C3 of the inner ring 30 .
  • a point a (first end point) is the center of the second ball 42 when the center of the second ball 42 is shown on the cross section including this central axis C3.
  • the point b (second end point) is the first straight line L1 and the first radial side of the first imaginary torus T1 on the cross section including the central axis C3 of the inner ring 30.
  • first line segment ab is a portion of the first straight line L1.
  • points a and b are out of phase by 180°.
  • FIG. 4 is a cross-sectional view showing the outer ring according to the first embodiment.
  • FIG. 5 is a cross-sectional view showing each inclined surface formed on the inner peripheral surface of the outer ring 20.
  • the outer ring 20 is made of steel such as high-carbon chromium bearing steel, carbon steel, or alloy steel.
  • the outer ring 20 has, from the axial first side to the second side, a fourth shoulder, a first outer ring raceway 21, a first inclined surface 23, a second inclined surface 24, It has a second outer ring raceway 22 and a third inclined surface 25 on the inner peripheral surface.
  • the inner peripheral surface of the outer ring 20 expands from the first outer ring raceway 21 to the third inclined surface 25 without decreasing in diameter.
  • the raceway contact diameter of the first outer ring raceway 21 is smaller than the raceway contact diameter of the second outer ring raceway 22 .
  • the first inclined surface 23 is formed on the inner peripheral surface of the outer ring 20 on the second side in the axial direction of the first outer ring raceway 21 and has a diameter that increases from the first side in the axial direction toward the second side. It is a conical surface that The second inclined surface 24 is formed on the second axial side of the first inclined surface 23 on the inner peripheral surface of the outer ring 20 and on the first axial side of the second outer ring raceway 22, It is a conical surface that expands in diameter from a first axial side toward a second axial side.
  • the third inclined surface 25 is formed on the inner peripheral surface of the outer ring 20 on the axial second side of the second outer ring raceway 22 , adjoins the front surface of the outer ring 20 , and extends from the axial first side to the third axial side. It is a conical surface that expands toward the side of 2.
  • the axial length of the second inclined surface 24 is preferably 1/10 to 1/2 of the axial length of the first inclined surface 23 .
  • the axial length of the third inclined surface 25 is preferably 1/10 to 1/2 of the axial length of the first inclined surface 23 .
  • a first inferiority plane formed by the first inclined surface 23 and the central axis C2 of the outer ring 20 in FIG. 5, a cylindrical surface centered on the central axis C2 of the outer ring 20.
  • the angle ⁇ 1 is the angle between the second inclined surface 24 and the central axis C2 of the outer ring 20 (in FIG. 5, a cylindrical surface centered on the central axis C2 of the outer ring 20) in a cross section including the central axis C2 of the outer ring 20. less than the minor angle ⁇ 2 of 2.
  • the first minor angle ⁇ 1 is between the third inclined surface 25 and the central axis C2 of the outer ring 20 (in FIG. ) is smaller than the third minor angle ⁇ 3 formed by
  • the first minor angle ⁇ 1 is preferably 12° or less.
  • the second minor angle ⁇ 2 is preferably 25° or more and 75° or less.
  • the third minor angle ⁇ 3 is preferably 25° or more and 75° or less.
  • a second straight line L2 is defined for convenience of explanation.
  • a first virtual torus T1 and a second virtual torus T2 are arranged on the outer ring 20 .
  • the centers of the plurality of first balls 41 arranged on the first outer ring raceway 21 when the inner ring assembly 35 and the outer ring 20 are assembled are aligned on the first great circle BC1.
  • the centers of the plurality of second balls 42 arranged on the second outer ring raceway 22 when the inner ring assembly 35 and the outer ring 20 are assembled are aligned on the second great circle BC2.
  • the second straight line L2 is defined in a cross section including the central axis C2 of the outer ring 20, along the central axis C2, the second great circle BC2 on the second radial side, and the first great circle BC2 on the first radial side. It is a straight line that intersects the most axial second side of the inclined surface 23 .
  • a point c is a point where the second straight line L2 and the second great circle BC2 (see FIG. 3) on the second side in the radial direction intersect in a cross section including the central axis C2 of the outer ring 20 .
  • a point c is the center of the second ball 42 when the center of the second ball 42 is shown on the cross section including the central axis C2. Note that the point c coincides with the point a in a cross section including the central axis C1 (C2, C3) of the ball bearing 10. As shown in FIG. Therefore, in this description, the point c is referred to as the "first end point" as well as the point a.
  • a point d is a point at which the second straight line L2 intersects the second most axial side of the first inclined surface 23 in a cross section including the central axis C2 of the outer ring 20.
  • a line segment whose endpoints are point c (first endpoint) and point d (third endpoint) will be referred to as a second line segment cd.
  • the second line segment cd is part of the second straight line L2.
  • the points c and d are out of phase by 180°.
  • the phase of point c is the same as the phase of point a
  • the phase of point d is the same as the phase of point b.
  • the ball bearing 10 is formed by combining an inner ring assembly 35 and an outer ring 20 .
  • a plurality of first balls 41 are arranged to roll on the first outer ring raceway 21 .
  • a plurality of second balls 42 are arranged to roll on the second outer ring raceway 22 .
  • the nominal contact point of the first inner ring raceway 31 is located on the second axial side of the nominal contact point of the first outer ring raceway 21 .
  • the nominal contact point of the second inner ring raceway 32 is located on the second axial side of the nominal contact point of the second outer ring raceway 22 .
  • the side surface on the first axial side of the inner ring 30 is the front surface of the inner ring 30
  • the side surface on the second axial side of the inner ring 30 is the rear surface of the inner ring 30
  • the side surface of the outer ring 20 on the first side in the axial direction is the back side of the outer ring 20
  • the side surface on the second side in the axial direction of the outer ring 20 is the front side of the outer ring 20 .
  • FIG. 6 is a cross-sectional view showing how the outer ring is assembled to the inner ring assembly of the ball bearing according to the first embodiment.
  • FIG. 6 shows a first ball bearing 10A, which is the ball bearing 10 according to the first embodiment.
  • the first ball bearing 10A has a first outer ring 20A which is the outer ring 20 according to the first embodiment.
  • the first outer ring raceway 21 in the first outer ring 20A is referred to as the first outer ring raceway 21A
  • the second outer ring raceway 22 as the second outer ring raceway 22A
  • the first inclined surface 23 as the first outer ring raceway 21A.
  • the inclined surface 23A and the second inclined surface 24 are called a second inclined surface 24A, and the third inclined surface 25 is called a third inclined surface 25A, respectively.
  • 10 A of 1st ball bearings are also simply called 10 A of ball bearings
  • 20 A of 1st outer rings are also simply called 20 A of outer rings.
  • the length of line segment ab is greater than the length of line segment cd.
  • the first outer ring 20A and inner ring assembly 35 shown in FIG. 6 have a point a (first end point) and a point c (second 1) are aligned with each other.
  • the inner ring assembly 35 is rotated about the tangent line of the second great circle BC2 passing through the point a (first end point) from this state, the length of the first line segment ab becomes the length of the line segment cd.
  • the first ball 41 on the first side in the radial direction cannot enter the first inclined surface 23A.
  • the first outer ring 20A and the inner ring assembly 35 are combined in a state where the central axis C3 of the inner ring 30 is inclined with respect to the central axis C2 of the first outer ring 20A. difficult to attach. Therefore, when assembling the first outer ring 20A to the inner ring assembly 35, there is a low possibility that the first ball 41 will come into contact with the first inclined surface 23A and be caught. That is, in the first ball bearing 10A having such a configuration, when the central axis C3 of the inner ring 30 is inclined with respect to the central axis C2 of the first outer ring 20A, the first outer ring 20A and the inner ring group Assembling the solid 35 is difficult.
  • FIG. 7 is a cross-sectional view showing the overall configuration of a ball bearing according to the second embodiment.
  • FIG. 8 is a cross-sectional view showing an outer ring according to the second embodiment.
  • FIG. 9 is a cross-sectional view showing how the outer ring is attached to the inner ring assembly of the ball bearing according to the second embodiment.
  • FIG. 7 shows a second ball bearing 10B, which is the ball bearing 10 according to the second embodiment.
  • the second ball bearing 10B differs from the first ball bearing 10A in that it has a second outer ring 20B (see FIG. 8) which is the outer ring 20 according to the second embodiment.
  • the first outer ring raceway 21 of the second outer ring 20B is referred to as the first outer ring raceway 21B
  • the second outer ring raceway 22 is referred to as the second outer ring raceway 22B
  • the first inclined surface 23 is referred to as the first outer ring raceway 21B
  • the inclined surface 23B and the second inclined surface 24 are called a second inclined surface 24B
  • the third inclined surface 25 is called a third inclined surface 25B.
  • the second ball bearing 10B is also simply called the ball bearing 10B
  • the first outer ring 20A is also simply called the outer ring 20B.
  • a point e is defined for convenience of explanation (see FIG. 8).
  • a point e (fourth end point) is a point located on the first inclined surface 23 on the first side in the radial direction in a cross section including the central axis C2 of the second outer ring 20B. 1st end point) is the shortest point.
  • a line segment having point c (first end point) and point e (fourth end point) as end points will be referred to as a third line segment ce.
  • the points c and e are out of phase by 180°.
  • the phase of point e is the same as the phase of point d.
  • the length of the first line segment ab is shorter than the length of the second line segment cd and shorter than the length of the third line segment ce.
  • the second outer ring 20B and inner ring assembly 35 shown in FIG. 9 have a point a (first end point) and a point c (second 1) are aligned with each other.
  • the inner ring assembly 35 is rotated about the tangent line of the second great circle BC2 passing through the point a (first end point) from this state, the first ball 41 enters the first inclined surface 23B. and can enter the first outer ring raceway 21B beyond the first inclined surface 23B. That is, in the second ball bearing 10B, when the second outer ring 20B is assembled to the inner ring assembly 35, the first balls 41 are less likely to be caught in contact with the first inclined surface 23B.
  • the second outer ring 20B and the inner ring assembly are arranged in a state in which the central axis C3 of the inner ring 30 is inclined with respect to the central axis C2 of the second outer ring 20B. Even if the three-dimensional body 35 is assembled, it can be easily assembled without being caught. In addition, since the possibility that the second outer ring 20B is caught by the inner ring assembly 35 is low, it is difficult to force the second outer ring 20B into the inner ring assembly 35. It is possible to reduce the possibility of being scratched by rubbing against 23B. Therefore, it can be evaluated that the second ball bearing 10B is excellent in assembling performance.
  • FIG. 10 is a cross-sectional view showing the overall configuration of a ball bearing according to a comparative example.
  • FIG. 11 is a cross-sectional view showing an outer ring according to a comparative example.
  • FIG. 12 is a cross-sectional view showing how the outer ring is attached to the inner ring assembly of the ball bearing according to the comparative example.
  • a ball bearing 60 shown in FIG. 10 differs from the ball bearing 10 of the present disclosure in that it has an outer ring 70 .
  • the ball bearing 60 includes an inner ring assembly 35 in common with the ball bearing 10 of the present disclosure.
  • the central axis of the ball bearing 60 will be referred to as central axis C4.
  • the central axis of the outer ring 70 is called central axis C5
  • the central axis of the inner ring 30 is called central axis C3.
  • the central axis C5 of the outer ring 70 and the central axis C3 of the inner ring 30 coincide with the central axis C4 of the ball bearing 60 in which the inner ring assembly 35 and the outer ring 70 are combined.
  • the inner peripheral surface of the outer ring 70 has a first inclined surface 73, a second inclined surface 74, a first inclined surface 73, a second inclined surface 74, a first outer ring raceway 71 and a second outer ring raceway 72. and a third inclined surface 75 are formed.
  • the first inclined surface 73 is formed on the inner peripheral surface of the outer ring 70 on the second side in the axial direction of the first outer ring raceway 71 and has a diameter that increases from the first side in the axial direction toward the second side. It is a conical surface that The second inclined surface 74 is formed on the second axial side of the first inclined surface 73 on the inner peripheral surface of the outer ring 70 and on the first axial side of the second outer ring raceway 72, It is a conical surface that expands in diameter from a first axial side toward a second axial side.
  • the third inclined surface 75 is formed on the inner peripheral surface of the outer ring 70 on the axial second side of the second outer ring raceway 72 , adjoins the front surface of the outer ring 70 , and extends from the axial first side to the third axial side. It is a conical surface that expands toward the side of 2.
  • a first minor angle ⁇ 101 formed between the first inclined surface 73 and the central axis C5 of the outer ring 70 in the cross section including the central axis C5 of the outer ring 70 is the second inclined surface in the cross section including the central axis C5 of the outer ring 70. 74 and the central axis C5 of the outer ring 70 is smaller than the second minor angle ⁇ 102.
  • first minor angle ⁇ 101 is smaller than third minor angle ⁇ 103 formed by third inclined surface 75 and central axis C5 of outer ring 70 .
  • points d and e similar to those of the second outer ring 20B (see FIG. 8) are defined (see FIG. 11).
  • the length of the first line segment ab is shorter than the length of the second line segment cd and longer than the length of the third line segment ce.
  • the ball bearing 60 differs from the ball bearing 10 (the first ball bearing 10A and the second ball bearing 10B) of the present disclosure in that it has such a dimensional relationship.
  • a ball bearing 60 according to a comparative example is not included in the ball bearing 10 of the present disclosure.
  • the outer ring 70 and the inner ring assembly 35 shown in FIG. 12 have a point a (first end point) and a point c (first end point) in a cross section including the central axis C5 of the outer ring 70 and the central axis C3 of the inner ring 30. are placed in a matching manner.
  • the inner ring assembly 35 is rotated about the tangent line of the second great circle BC2 passing through the point a (first end point) from this state, the first ball 41 on the first side in the radial direction Although it can enter the first inclined surface 73 , it cannot go over the first inclined surface 73 and enter the first outer ring raceway 71 .
  • the ball bearing 60 when the outer ring 70 is assembled to the inner ring assembly 35, the first ball 41 may come into contact with the first inclined surface 73 and be caught. Further, if the outer ring 70 in the hooked state is forcibly pushed into the inner ring assembly 35, the first ball 41 may rub against the first inclined surface 73 and be damaged. For this reason, the ball bearing 60 can be evaluated as having poor assembling properties.
  • the ball bearings 10A, 10B in the embodiments described above include an inner ring assembly 35 and outer rings 20A, 20B.
  • the inner ring assembly 35 includes an inner ring 30 , a plurality of first balls 41 , a plurality of second balls 42 , a first retainer 51 and a second retainer 52 .
  • the inner ring 30 has a first inner ring raceway 31 on the first side in the axial direction and a second inner ring raceway 32 on the second side in the axial direction of the first inner ring raceway 31 on its outer peripheral surface. There is The raceway contact diameter of the first inner ring raceway 31 is smaller than the raceway contact diameter of the second inner ring raceway 32 .
  • a plurality of first balls 41 are arranged to roll on the first inner ring raceway 31 .
  • the first retainer 51 has a plurality of first pockets 53 .
  • the plurality of first balls 41 are slidably arranged in the first pocket 53 .
  • a plurality of second balls 42 are arranged to roll on the second inner ring raceway 32 .
  • the second retainer 52 has a plurality of second pockets 54 .
  • a plurality of second balls 42 are slidably disposed in the second pocket 54 .
  • the inner ring 30, the plurality of first balls 41, the plurality of second balls 42, the first retainer 51, and the second retainer 52 are configured so as not to separate.
  • the pitch diameter of the ball set in the row of the first balls 41 formed by the plurality of first balls 41 of the inner ring assembly 35 is the same as the pitch diameter of the balls in the row of the second balls 42 formed by the plurality of second balls 42. Smaller than the pitch diameter of the set.
  • the outer rings 20A, 20B have first outer ring raceways 21A, 21B, first inclined surfaces 23A, 23B, and second inclined surfaces 24A, 24B from the first side in the axial direction to the second side. , and second outer ring raceways 22A and 22B on the inner peripheral surface.
  • the inner peripheral surfaces of the outer rings 20A, 20B expand from the first outer ring raceways 21A, 21B to the second outer ring raceways 22A, 22B without decreasing in diameter, and the raceway contact diameters of the first outer ring raceways 21A, 21B are , is smaller than the raceway contact diameter of the second outer ring raceway 22A, 22B.
  • the diameter of the plurality of first balls 41 is smaller than the diameter of the plurality of second balls 42 .
  • a plurality of first balls 41 are arranged so as to be able to roll on the first outer ring raceways 21A and 21B.
  • a plurality of second balls 42 are arranged so as to be able to roll on the second outer ring raceways 22A and 22B.
  • the nominal contact point of the first inner ring raceway 31 is located on the second side in the axial direction from the nominal contact point of the first outer ring raceways 21A, 21B.
  • the nominal contact point of the second inner ring raceway 32 is located on the second side in the axial direction from the nominal contact point of the second outer ring raceways 22A, 22B.
  • the first inclined surfaces 23A, 23B are formed on the second side in the axial direction of the first outer ring raceways 21A, 21B on the inner peripheral surfaces of the outer rings 20A, 20B. It is an inclined surface that expands in diameter toward the side.
  • the second inclined surfaces 24A, 24B are located on the second side in the axial direction of the first inclined surfaces 23A, 23B on the inner peripheral surfaces of the outer rings 20A, 20B and in the axial direction of the second outer ring raceways 22A, 22B. It is an inclined surface formed on the first side and increasing in diameter from the first side toward the second side in the axial direction.
  • a first minor angle ⁇ 1 formed by the first inclined surfaces 23A, 23B and the central axis C2 of the outer rings 20A, 20B in a cross section including the central axis C2 of the outer rings 20A, 20B includes the central axis C2 of the outer rings 20A, 20B.
  • the center of each first ball 41 of the plurality of first balls 41 is on the first great circle BC1
  • the half of the diameter of the first ball 41 is defined as the first small radius Sr1, which is the radius of the first small circle SC1
  • the half of the pitch diameter of the ball set in the row of the first balls 41 is defined as the diameter of the first great circle BC1.
  • a torus having a first major radius Br1, which is a radius, is defined as a first virtual torus T1.
  • the second small radius Sr2 which is the radius of the second small circle SC2 is half the diameter of the second ball 42, and the half of the pitch diameter of the ball set in the row of the second balls 42 is the second great circle BC2.
  • a torus having a second large radius Br2, which is a radius, is defined as a second virtual torus T2. In a cross section including the bearing central axis C1, a radial first side and a radial second side opposite to the radial first side by 180° in the circumferential direction are defined.
  • a second great circle BC2 on the second side as the first end points a, c, a first great circle BC1 on the first radial side and a second great circle BC2 on the second radial side and the surface of the first imaginary torus T1 on the first side in the radial direction.
  • the line segment connecting c and the second end point b is defined as a first line segment ab
  • the second most axial side of the first inclined surfaces 23A and 23B on the first side in the radial direction is defined as the third side.
  • a line segment connecting the first end points a and c and the third end point d is defined as a second line segment cd, which lies on the first inclined surfaces 23A and 23B on the first side in the radial direction.
  • a point closest to the first end points a and c is defined as a fourth end point e
  • a line segment connecting the first end points a and c and the fourth end point e is defined as a third line segment ce.
  • the length of the first line segment ab is greater than the length of the second line segment cd (in the case of the outer ring 20A), or the length of the first line segment ab is greater than the length of the second line segment cd. It is smaller than the length of the line segment cd, and the length of the first line segment ab is smaller than the length of the third line segment ce (in the case of the outer ring 20B).
  • the ball bearings 10A and 10B having such a configuration, when the outer ring 20 is assembled to the inner ring assembly 35, the first balls 41 do not come into contact with the first inclined surface 23 of the outer ring 20. It is possible to prevent the outer ring 20 from being caught and stopped in a state where the first ball 41 is in contact with the inclined surface 23 of . Therefore, according to the ball bearings 10A and 10B shown in the above embodiment, it is possible to improve the assembling property of the outer ring 20 to the inner ring assembly 35 .
  • the outer rings 20A and 20B are provided with first outer ring raceways 21A and 21B and first inclined surfaces on the inner peripheral surface from the first side toward the second side in the axial direction. 23A, 23B, second inclined surfaces 24A, 24B, second outer ring raceways 22A, 22B, and third inclined surfaces 25A, 25B.
  • the inner peripheral surfaces of the outer rings 20A, 20B expand without decreasing in diameter from the first outer ring raceways 21A, 21B to the third inclined surfaces 25A, 25B.
  • the first minor angle ⁇ 1 is the third angle between the third inclined surfaces 25A, 25B and the central axes C2 of the outer rings 20A, 20B in the cross section containing the central axes C2 of the outer rings 20A, 20B. It is smaller than the minor angle ⁇ 3. According to the ball bearings 10A and 10B having such a configuration, it is possible to improve the assembling property of the outer ring 20 to the inner ring assembly 35 .
  • the plurality of second balls 42 and a virtual plane including the front surfaces of the second sides of the outer rings 20A and 20B in the axial direction and perpendicular to the central axes of the outer rings 20A and 20B are: They overlap in the axial direction.
  • the assembly of the outer rings 20A and 20B to the inner ring assembly 35 can be improved. can.

Abstract

A ball bearing (10) in which, in a cross section including a center axis (C2), a first inferior angle (θ1) formed by a first inclined surface (23) and the center axis (C2) is smaller than a second inferior angle (θ2) formed by a second inclined surface (24) and the center axis (C2) and, in a cross section including a center axis (C1), when a second large circle (BC2) on a second side in the radial direction is a first end point (a, c), an intersection between a first straight line (L1) passing through a first large circle (BC1) on the first side in the radial direction and the second large circle (BC2) on the second side in the radial direction and a surface of a first imaginary torus (T1) on a first side in the radial direction is a second end point (b),the first inclined surface (23) on the first side in the radial direction closest to a second side in the axial direction is a third end point (d), and a point that is on the first inclined surface (23) on the first side in the radial direction and has the shortest distance from the first end point (a) is a fourth end point (e), the length of a first line segment (ab) is longer than the length of a second line segment (cd) or the length of the first line segment (ab) is shorter than the length of a second line segment (cd) and the length of the first line segment (ab) is shorter than the length of a third line segment (ce).

Description

玉軸受ball bearing
　本開示は、玉軸受に関する。 This disclosure relates to ball bearings.
　従来、複列玉軸受のアンギュラ玉軸受であって、各玉の列の軸受中心軸と作用線との劣角を同じ方向にし、各玉の列の玉セットのピッチ径を異ならせ、単列玉軸受のアンギュラ玉軸受よりも大きなアキシアル荷重を負荷できる玉軸受が知られている。このような玉軸受は、タンデム形と称される。 Conventionally, angular contact ball bearings of double-row ball bearings have the minor angle between the bearing central axis and the line of action of each row of balls arranged in the same direction, and the pitch diameter of the ball set of each row of balls is made different, and the single-row A ball bearing is known that can bear a greater axial load than an angular contact ball bearing. Such ball bearings are called tandem type.
　図１３は従来の玉軸受を示す断面図である。従来の玉軸受２１０は、内輪組立体２３５と、外輪２２０と、を備える。内輪組立体２３５は、内輪２３０と、複数の第１の玉２４１と、複数の第２の玉２４２と、第１の保持器２５１と、第２の保持器２５２と、を備える。複数の第１の玉２４１の直径と複数の第２の玉２４２の直径とは同一である。内輪２３０は、軸方向の第１の側の第１の内輪軌道２３１と、第１の内輪軌道２３１の軸方向の第２の側の第２の内輪軌道２３２と、を外周面に有する。第１の内輪軌道２３１の軌道接触直径は、第２の内輪軌道２３２の軌道接触直径よりも小さい。複数の第１の玉２４１は、第１の内輪軌道２３１に転動可能に配置される。第１の保持器２５１は、複数のポケットを有する。複数の第１の玉２４１は、第１の保持器２５１の複数のポケットに摺動可能に配置される。第１の保持器２５１の複数のポケットの径方向の外側の開口の内接円の直径は、第１の玉２４１の直径よりも小さいので、複数の第１の玉２４１をそれぞれ第１の保持器２５１の各ポケットに配置して第１の内輪軌道２３１に配置したとき、内輪２３０と、複数の第１の玉２４１と、第１の保持器２５１と、は分離しない。複数の第２の玉２４２は、第２の内輪軌道２３２に転動可能に配置される。第２の保持器２５２は、複数のポケットを有する。複数の第２の玉２４２は、第２の保持器２５２の複数のポケットに摺動可能に配置される。第２の保持器２５２の複数のポケットの径方向の外側の開口の内接円の直径は、第２の玉２４２の直径よりも小さいので、複数の第２の玉２４２をそれぞれ第２の保持器２５２の各ポケットに配置して第２の内輪軌道２３２に配置したとき、内輪２３０と、複数の第２の玉２４２と、第２の保持器２５２と、は分離しない。内輪組立体２３５は、内輪２３０と、複数の第１の玉２４１と、複数の第２の玉２４２と、第１の保持器２５１と、第２の保持器２５２と、が分離しないように組み立てられている。内輪組立体２３５の、複数の第１の玉２４１が構成する第１の玉２４１の列の玉セットのピッチ径は、複数の第２の玉２４２が構成する第２の玉２４２の列の玉セットのピッチ径よりも小さい。 Fig. 13 is a sectional view showing a conventional ball bearing. A conventional ball bearing 210 comprises an inner ring assembly 235 and an outer ring 220 . The inner ring assembly 235 includes an inner ring 230 , a plurality of first balls 241 , a plurality of second balls 242 , a first retainer 251 and a second retainer 252 . The diameter of the plurality of first balls 241 and the diameter of the plurality of second balls 242 are the same. The inner ring 230 has a first inner ring raceway 231 on the first side in the axial direction and a second inner ring raceway 232 on the second side in the axial direction of the first inner ring raceway 231 on the outer peripheral surface. The raceway contact diameter of the first inner ring raceway 231 is smaller than the raceway contact diameter of the second inner ring raceway 232 . A plurality of first balls 241 are arranged to roll on the first inner ring raceway 231 . The first retainer 251 has multiple pockets. A plurality of first balls 241 are slidably disposed in a plurality of pockets of the first retainer 251 . Since the diameter of the inscribed circle of the radially outer openings of the plurality of pockets of the first retainer 251 is smaller than the diameter of the first balls 241, the plurality of first balls 241 are each held in the first holding state. When arranged in each pocket of the container 251 and arranged on the first inner ring raceway 231, the inner ring 230, the plurality of first balls 241 and the first retainer 251 are not separated. A plurality of second balls 242 are arranged to roll on the second inner ring raceway 232 . The second retainer 252 has multiple pockets. A plurality of second balls 242 are slidably disposed in a plurality of pockets of the second retainer 252 . Since the diameter of the inscribed circle of the radially outer openings of the plurality of pockets of the second retainer 252 is smaller than the diameter of the second balls 242, the plurality of second balls 242 are each held in the second holding state. The inner ring 230, the plurality of second balls 242, and the second retainer 252 do not separate when placed in each pocket of the container 252 and placed on the second inner ring raceway 232. The inner ring assembly 235 is assembled so that the inner ring 230, the plurality of first balls 241, the plurality of second balls 242, the first retainer 251, and the second retainer 252 are not separated. It is The pitch diameter of the ball set in the row of the first balls 241 formed by the plurality of first balls 241 of the inner ring assembly 235 is the same as the pitch diameter of the balls in the row of the second balls 242 formed by the plurality of second balls 242. Smaller than the pitch diameter of the set.
　外輪２２０は、軸方向の第１の側の第１の外輪軌道２２１と、第１の外輪軌道２２１の軸方向の第２の側の第２の外輪軌道２２２と、を内周面に有する。第１の外輪軌道２２１の軌道接触直径は、第２の外輪軌道２２２の軌道接触直径よりも小さい。玉軸受２１０は、内輪組立体２３５と外輪２２０とを組み合わせてなる。 The outer ring 220 has a first outer ring raceway 221 on the first side in the axial direction and a second outer ring raceway 222 on the second side in the axial direction of the first outer ring raceway 221 on its inner peripheral surface. The raceway contact diameter of the first outer ring raceway 221 is smaller than the raceway contact diameter of the second outer ring raceway 222 . Ball bearing 210 is formed by combining inner ring assembly 235 and outer ring 220 .
　玉軸受２１０において、複数の第１の玉２４１は、第１の外輪軌道２２１に転動可能に配置され、複数の第２の玉２４２は、第２の外輪軌道２２２に転動可能に配置される。第１の内輪軌道２３１の呼び接触点は、第１の外輪軌道２２１の呼び接触点より軸方向の第２の側に位置する。第２の内輪軌道２３２の呼び接触点は、第２の外輪軌道２２２の呼び接触点より軸方向の第２の側に位置する。よって、内輪２３０の軸方向の第１の側の側面が内輪２３０の正面であり、軸方向の第２の側の側面が内輪２３０の背面である。また、外輪２２０の軸方向の第１の側の側面が外輪２２０の背面であり、軸方向の第２の側の側面が外輪２２０の正面である。玉軸受２１０は、玉の列が２列あるため、この玉軸受２１０が負荷できるアキシアル荷重は、単列のアンギュラ玉軸受が負荷できるアキシアル荷重よりも大きい（例えば、特許文献１参照）。 In the ball bearing 210, the plurality of first balls 241 are rollably arranged on the first outer ring raceway 221, and the plurality of second balls 242 are rollably arranged on the second outer ring raceway 222. be. The nominal contact point of the first inner ring raceway 231 is located on the second axial side of the nominal contact point of the first outer ring raceway 221 . The nominal contact point of the second inner ring raceway 232 is located on the second axial side of the nominal contact point of the second outer ring raceway 222 . Thus, the side surface on the first axial side of the inner ring 230 is the front surface of the inner ring 230 , and the side surface on the second axial side is the rear surface of the inner ring 230 . Further, the side surface of the outer ring 220 on the first side in the axial direction is the rear surface of the outer ring 220 , and the side surface on the second side in the axial direction is the front surface of the outer ring 220 . Since the ball bearing 210 has two rows of balls, the axial load that the ball bearing 210 can bear is larger than the axial load that a single-row angular contact ball bearing can bear (see, for example, Patent Document 1).
　一方、従来の玉軸受２１０は、第１の玉２４１の直径と第２の玉２４２の直径とが同じである。この場合、第１の玉２４１の列と第１の内輪軌道２３１と第１の外輪軌道２２１に係る寿命と、第２の玉２４２の列と第２の内輪軌道２３２と第２の外輪軌道２２２に係る寿命とが大きく相違する事がある。従来の玉軸受２１０の複数の第１の玉２４１の直径を複数の第２の玉２４２の直径に比べて小さくすることで、第１の玉２４１の列の寿命と第２の玉２４２の列の寿命との差を小さくすることができ、玉軸受２１０の寿命・剛性・トルク等を最適化することが可能となる。 On the other hand, in the conventional ball bearing 210, the diameter of the first ball 241 and the diameter of the second ball 242 are the same. In this case, the life of the first row of balls 241, the first inner ring raceway 231, and the first outer ring raceway 221, the life of the second row of balls 242, the second inner ring raceway 232, and the second outer ring raceway 222 It may be greatly different from the life related to. By making the diameter of the plurality of first balls 241 of the conventional ball bearing 210 smaller than the diameter of the plurality of second balls 242, the life of the row of the first balls 241 and the life of the row of the second balls 242 are reduced. , and the life, rigidity, torque, etc. of the ball bearing 210 can be optimized.
特開２０１５－１９４２４４号公報JP 2015-194244 A
　本開示の玉軸受は、内輪組立体と、外輪と、を備え、前記内輪組立体は、内輪と、複数の第１の玉と、複数の第２の玉と、第１の保持器と、第２の保持器と、を備え、前記内輪は、軸方向の第１の側に第１の内輪軌道と、前記第１の内輪軌道の軸方向の第２の側に第２の内輪軌道と、を外周面に有し、前記第１の内輪軌道の軌道接触直径は、前記第２の内輪軌道の軌道接触直径よりも小さく、前記複数の第１の玉は、前記第１の内輪軌道に転動可能に配置され、前記第１の保持器は、複数の第１のポケットを有し、前記複数の第１の玉は、前記第１のポケットに摺動可能に配置され、前記複数の第２の玉は、前記第２の内輪軌道に転動可能に配置され、前記第２の保持器は、複数の第２のポケットを有し、前記複数の第２の玉は、前記第２のポケットに摺動可能に配置され、前記内輪と、前記複数の第１の玉と、前記複数の第２の玉と、前記第１の保持器と、前記第２の保持器と、が分離しないよう構成され、前記内輪組立体の、前記複数の第１の玉が構成する当該第１の玉の列の玉セットのピッチ径は、前記複数の第２の玉が構成する当該第２の玉の列の玉セットのピッチ径よりも小さく、前記外輪は、軸方向の第１の側から第２の側に向かって、第１の外輪軌道と、第１の傾斜面と、第２の傾斜面と、第２の外輪軌道と、を内周面に有し、前記外輪の内周面は、前記第１の外輪軌道から前記第２の外輪軌道まで直径が縮小することなく拡大し、前記第１の外輪軌道の軌道接触直径は、前記第２の外輪軌道の軌道接触直径よりも小さく、前記複数の第１の玉の直径は、前記複数の第２の玉の直径よりも小さく、前記複数の第１の玉は、前記第１の外輪軌道に転動可能に配置され、前記複数の第２の玉は、前記第２の外輪軌道に転動可能に配置され、前記第１の内輪軌道の呼び接触点は、前記第１の外輪軌道の呼び接触点より軸方向の第２の側に位置し、前記第２の内輪軌道の呼び接触点は、前記第２の外輪軌道の呼び接触点より軸方向の第２の側に位置し、前記第１の傾斜面は、前記外輪の内周面における前記第１の外輪軌道の軸方向の第２の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面であり、前記第２の傾斜面は、前記外輪の内周面における前記第１の傾斜面の軸方向の第２の側であって前記第２の外輪軌道の軸方向の第１の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面であり、前記外輪の中心軸を含む断面において前記第１の傾斜面と前記外輪の中心軸とがなす第１の劣角が、前記外輪の中心軸を含む断面において前記第２の傾斜面と前記外輪の中心軸とがなす第２の劣角よりも小さく、かつ、前記複数の第１の玉を前記第１の内輪軌道に配置し接触させた時に、前記複数の第１の玉の各第１の玉の中心が第１の大円上にあり、前記第１の玉の直径の半分を第１の小円の半径である第１の小半径とし、前記第１の玉の列の玉セットのピッチ径の半分を前記第１の大円の半径である第１の大半径とするトーラスを第１の仮想トーラスと、定義し、前記複数の第２の玉を前記第２の内輪軌道に配置し接触させた時に、前記複数の第２の玉の各第２の玉の中心が第２の大円上にあり、前記第２の玉の直径の半分を第２の小円の半径である第２の小半径とし、前記第２の玉の列の玉セットのピッチ径の半分を前記第２の大円の半径である第２の大半径とするトーラスを第２の仮想トーラスと、定義し、軸受中心軸を含む断面において、径方向の第１の側と径方向の第１の側とは周方向に１８０°反対側である径方向の第２の側とを定義し、径方向の第２の側の前記第２の大円を第１の端点とし、径方向の第１の側の前記第１の大円と径方向の第２の側の前記第２の大円とを通る直線と径方向の第１の側の前記第１の仮想トーラスの径方向の第１の側の表面との交点を第２の端点とし、前記第１の端点と前記第２の端点とを結ぶ線分を第１の線分とし、径方向の第１の側の前記第１の傾斜面の最も軸方向の第２の側を第３の端点とし、前記第１の端点と前記第３の端点とを結ぶ線分を第２の線分とし、径方向の第１の側の前記第１の傾斜面上にあり前記第１の端点から最も距離の小さい点を第４の端点とし、前記第１の端点と前記第４の端点とを結ぶ線分を第３の線分とし、前記第１の線分の長さが前記第２の線分の長さよりも大きい、又は、前記第１の線分の長さが前記第２の線分の長さよりも小さく、かつ、前記第３の線分の長さよりも小さい。 A ball bearing of the present disclosure comprises an inner ring assembly, an outer ring, the inner ring assembly comprising an inner ring, a plurality of first balls, a plurality of second balls, a first cage, and a second retainer, the inner ring having a first inner ring raceway on a first axial side and a second inner ring raceway on a second axial side of the first inner ring raceway; , on the outer peripheral surface, the raceway contact diameter of the first inner ring raceway is smaller than the raceway contact diameter of the second inner ring raceway, and the plurality of first balls are arranged on the first inner ring raceway. Rollably arranged, the first retainer has a plurality of first pockets, the plurality of first balls are slidably arranged in the first pockets, the plurality of A second ball is rotatably disposed on the second inner ring raceway, the second retainer has a plurality of second pockets, the plurality of second balls are arranged in the second The inner ring, the plurality of first balls, the plurality of second balls, the first retainer, and the second retainer are separated from each other. and the pitch diameter of the ball set in the first row of balls formed by the plurality of first balls of the inner ring assembly is equal to the pitch diameter of the second ball formed by the plurality of second balls. The outer ring has a first outer ring raceway, a first inclined surface and a second having an inclined surface and a second outer ring raceway on the inner peripheral surface, the inner peripheral surface of the outer ring expanding without decreasing in diameter from the first outer ring raceway to the second outer ring raceway; the raceway contact diameter of the first outer ring raceway is smaller than the raceway contact diameter of the second outer ring raceway, the diameter of the plurality of first balls is smaller than the diameter of the plurality of second balls; The plurality of first balls are rollably arranged on the first outer ring raceway, the plurality of second balls are rollably arranged on the second outer ring raceway, and the first ball is arranged to roll on the second outer ring raceway. The nominal contact point of the inner ring raceway is located on the second side in the axial direction from the nominal contact point of the first outer ring raceway, and the nominal contact point of the second inner ring raceway is the nominal contact point of the second outer ring raceway. Positioned on the second side in the axial direction from the contact point, the first inclined surface is formed on the second side in the axial direction of the first outer ring raceway on the inner peripheral surface of the outer ring. It is an inclined surface that expands in diameter from a first side toward a second side, and the second inclined surface is on the second side in the axial direction of the first inclined surface on the inner peripheral surface of the outer ring. an inclined surface formed on a first side in the axial direction of the second outer ring raceway and increasing in diameter from the first side to the second side in the axial direction, including the central axis of the outer ring A first minor angle formed by the first inclined surface and the central axis of the outer ring in a cross section is equal to a second minor angle formed by the second inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring. and when the plurality of first balls are arranged and brought into contact with the first inner ring raceway, the center of each first ball of the plurality of first balls is positioned at the first A first minor radius, which is the radius of the first minor circle, is half the diameter of the first ball on the great circle, and half the pitch diameter of the ball set in the first row of balls is the first minor radius. A torus with a first major radius that is the radius of one great circle is defined as a first virtual torus, and when the plurality of second balls are arranged and brought into contact with the second inner ring raceway, the The center of each second ball of the plurality of second balls is on the second great circle, and half the diameter of the second ball is the second minor radius, which is the radius of the second small circle; A second virtual torus is defined as a torus having a second major radius, which is the radius of the second great circle, which is half the pitch diameter of the ball set of the second row of balls, and includes the bearing center axis. In a cross-section, a radial first side and a radial second side that is 180° circumferentially opposite the radial first side are defined, and the radial second side A straight line passing through the first great circle on the first side in the radial direction and the second great circle on the second side in the radial direction and the second great circle in the radial direction A second end point is defined as an intersection point of the first virtual torus on the first side with the surface of the first side in the radial direction, and a line segment connecting the first end point and the second end point is defined as the first end point. a line segment, a line segment connecting the first end point and the third end point, with a third end point on the second side in the axial direction of the first inclined surface on the first side in the radial direction; is a second line segment, a point on the first inclined surface on the first side in the radial direction and the shortest distance from the first end point is the fourth end point, and the first end point and the A line segment connecting the fourth end point is defined as a third line segment, and the length of the first line segment is greater than the length of the second line segment, or the length of the first line segment is is smaller than the length of the second line segment and smaller than the length of the third line segment.
　本開示の玉軸受は、前記外輪は、内周面に軸方向の第１の側から第２の側に向かって、前記第１の外輪軌道と、前記第１の傾斜面と、前記第２の傾斜面と、前記第２の外輪軌道と、さらに第３の傾斜面を有し、前記外輪の内周面は、前記第１の外輪軌道から前記第３の傾斜面まで直径が縮小することなく拡大し、前記第１の劣角が、前記外輪の中心軸を含む断面において前記第３の傾斜面と前記外輪の中心軸とがなす第３の劣角よりも小さい。 In the ball bearing of the present disclosure, the outer ring has the first outer ring raceway, the first inclined surface, and the second radial direction on the inner peripheral surface from the first side in the axial direction toward the second side. , the second outer ring raceway, and a third inclined surface, and the inner peripheral surface of the outer ring is reduced in diameter from the first outer ring raceway to the third inclined surface. The first minor angle is smaller than the third minor angle formed by the third inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring.
　本開示の玉軸受は、前記複数の第２の玉と、前記外輪の軸方向の第２の側の正面を含み当該外輪の中心軸に垂直な仮想平面とが、軸方向において重なっている。 In the ball bearing of the present disclosure, the plurality of second balls and an imaginary plane including the front surface of the second axial side of the outer ring and perpendicular to the central axis of the outer ring overlap in the axial direction.
第１実施形態に係る玉軸受の全体構成を示す断面図である。It is a sectional view showing the whole ball bearing composition concerning a 1st embodiment. 内輪組立体を示す断面図である。It is a sectional view showing an inner ring assembly. 第１仮想トーラス及び第２仮想トーラスの概略を示す模式図である。FIG. 3 is a schematic diagram showing an outline of a first virtual torus and a second virtual torus; 第１実施形態に係る外輪を示す断面図である。It is a sectional view showing an outer race concerning a 1st embodiment. 外輪の内周面に形成された各傾斜面を示す断面図である。FIG. 4 is a cross-sectional view showing each inclined surface formed on the inner peripheral surface of the outer ring; 第１実施形態に係る玉軸受の内輪組立体に対する外輪の組付状況を示す断面図である。FIG. 3 is a cross-sectional view showing how the outer ring is assembled to the inner ring assembly of the ball bearing according to the first embodiment; 第２実施形態に係る玉軸受の全体構成を示す断面図である。It is a sectional view showing the whole ball bearing composition concerning a 2nd embodiment. 第２実施形態に係る外輪を示す断面図である。It is a sectional view showing an outer race concerning a 2nd embodiment. 第２実施形態に係る玉軸受の内輪組立体に対する外輪の組付状況を示す断面図である。FIG. 7 is a cross-sectional view showing how the outer ring is assembled to the inner ring assembly of the ball bearing according to the second embodiment; 比較例に係る玉軸受の全体構成を示す断面図である。It is a sectional view showing the whole ball bearing composition concerning a comparative example. 比較例に係る外輪を示す断面図である。FIG. 3 is a cross-sectional view showing an outer ring according to a comparative example; 比較例に係る玉軸受の内輪組立体に対する外輪の組付状況を示す断面図である。FIG. 5 is a cross-sectional view showing how an outer ring is attached to an inner ring assembly of a ball bearing according to a comparative example; 従来の玉軸受を示す断面図である。FIG. 10 is a cross-sectional view showing a conventional ball bearing; 比較例の玉軸受における内輪組立体に対する外輪の組付状況を示す断面図である。FIG. 4 is a cross-sectional view showing how an outer ring is attached to an inner ring assembly in a ball bearing of a comparative example;
＜本開示の発明が解決しようとする課題＞
　図１４は、比較例の玉軸受における内輪組立体に対する外輪の組付状況を示す断面図である。図１４の複列玉軸受は、図１３に示す従来の複列玉軸受２１０の第２の玉２４２を第１の玉２４１よりも大きくして、玉軸受２１０の寿命・剛性・トルク等を最適化する構成である。比較例の複列玉軸受１１０は、内輪組立体１３５と、外輪１２０と、を備える。内輪組立体１３５は、内輪１３０と、複数の第１の玉１４１と、複数の第２の玉１４２と、第１の保持器１５１と、第２の保持器１５２と、を備える。内輪１３０は、軸方向の第１の側の第１の内輪軌道１３１と、第１の内輪軌道１３１の軸方向の第２の側の第２の内輪軌道１３２と、を外周面に有する。第１の内輪軌道１３１の軌道接触直径は、第２の内輪軌道１３２の軌道接触直径よりも小さい。複数の第１の玉１４１は、第１の内輪軌道１３１に転動可能に配置される。第１の保持器１５１は、複数のポケットを有する。複数の第１の玉１４１は、第１の保持器１５１の複数のポケットに摺動可能に配置される。第１の保持器１５１の複数のポケットの径方向の外側の開口の内接円の直径が第１の玉１４１の直径よりも小さいので、複数の第１の玉１４１をそれぞれ第１の保持器１５１の各ポケットに配置して第１の内輪軌道１３１に配置したとき、内輪１３０と、複数の第１の玉１４１と、第１の保持器１５１と、は分離しない。複数の第２の玉１４２は、第２の内輪軌道１３２に転動可能に配置される。第２の保持器１５２は、複数のポケットを有する。複数の第２の玉１４２は、第２の保持器１５２の複数のポケットに摺動可能に配置される。第２の保持器１５２の複数のポケットの径方向の外側の開口の内接円の直径が第２の玉１４２の直径よりも小さいので、複数の第２の玉１４２をそれぞれ第２の保持器１５２の各ポケットに配置して第２の内輪軌道１３２に配置したとき、内輪１３０と、複数の第２の玉１４２と、第２の保持器１５２と、は分離しない。このように、内輪１３０と、複数の第１の玉１４１と、複数の第２の玉１４２と、第１の保持器１５１と、第２の保持器１５２と、が分離しないよう構成される。内輪組立体１３５の、複数の第１の玉１４１が構成する第１の玉１４１の列の玉セットのピッチ径は、複数の第２の玉１４２が構成する第２の玉１４２の列の玉セットのピッチ径よりも小さい。前記複数の第１の玉１４１の直径は、前記複数の第２の玉１４２の直径よりも小さい。外輪１２０は、軸方向の第１の側から第２の側に向かって、第１の外輪軌道１２１と、第１の傾斜面１２３と、第２の傾斜面１２４と、第２の外輪軌道１２２と、第３の傾斜面１２５と、を内周面に有する。外輪１２０の内周面は、第１の外輪軌道１２１から第３の傾斜面１２５まで直径が縮小することなく拡大する。第１の外輪軌道１２１の軌道接触直径は、第２の外輪軌道１２２の軌道接触直径よりも小さい。玉軸受１１０は、内輪組立体１３５と外輪１２０とを組み合わせてなる。複数の第１の玉１４１は、第１の外輪軌道１２１に転動可能に配置される。複数の第２の玉１４２は、第２の外輪軌道１２２に転動可能に配置される。第１の内輪軌道１３１の呼び接触点は、第１の外輪軌道１２１の呼び接触点より軸方向の第２の側に位置する。第２の内輪軌道１３２の呼び接触点は、第２の外輪軌道１２２の呼び接触点より軸方向の第２の側に位置する。第１の傾斜面１２３は、外輪１２０の内周面における第１の外輪軌道１２１の軸方向の第２の側に形成され、軸方向の第１の側から第２の側に向かって拡径する円すい面である。第２の傾斜面１２４は、外輪１２０の内周面における第１の傾斜面１２３の軸方向の第２の側であって第２の外輪軌道１２２の軸方向の第１の側に形成され、軸方向の第１の側から第２の側に向かって拡径する円すい面である。第３の傾斜面１２５は、外輪１２０の内周面における第２の外輪軌道１２２の軸方向の第２の側に形成され、外輪１２０の正面に隣接し、軸方向の第１の側から第２の側に向かって拡径する円すい面である。 <Problems to be Solved by the Invention of the Present Disclosure>
FIG. 14 is a cross-sectional view showing how the outer ring is attached to the inner ring assembly in the ball bearing of the comparative example. In the double-row ball bearing of FIG. 14, the second balls 242 of the conventional double-row ball bearing 210 shown in FIG. It is a configuration that converts A double-row ball bearing 110 of the comparative example includes an inner ring assembly 135 and an outer ring 120 . The inner ring assembly 135 includes an inner ring 130 , a plurality of first balls 141 , a plurality of second balls 142 , a first retainer 151 and a second retainer 152 . The inner ring 130 has a first inner ring raceway 131 on the first side in the axial direction and a second inner ring raceway 132 on the second side in the axial direction of the first inner ring raceway 131 on the outer peripheral surface. The raceway contact diameter of the first inner ring raceway 131 is smaller than the raceway contact diameter of the second inner ring raceway 132 . A plurality of first balls 141 are arranged to roll on the first inner ring raceway 131 . The first retainer 151 has multiple pockets. The plurality of first balls 141 are slidably arranged in the plurality of pockets of the first retainer 151 . Since the diameter of the inscribed circle of the radially outer openings of the plurality of pockets of the first retainer 151 is smaller than the diameter of the first balls 141, the plurality of first balls 141 are respectively attached to the first retainer. 151 and placed on the first inner ring raceway 131, the inner ring 130, the plurality of first balls 141 and the first retainer 151 are not separated. A plurality of second balls 142 are arranged to roll on the second inner ring raceway 132 . The second retainer 152 has multiple pockets. A plurality of second balls 142 are slidably disposed in a plurality of pockets of the second retainer 152 . Since the diameter of the inscribed circle of the radially outer openings of the plurality of pockets of the second retainer 152 is smaller than the diameter of the second balls 142, the plurality of second balls 142 are respectively attached to the second retainer. When placed in each pocket of 152 and placed on the second inner ring raceway 132, the inner ring 130, the plurality of second balls 142 and the second retainer 152 do not separate. Thus, the inner ring 130, the plurality of first balls 141, the plurality of second balls 142, the first retainer 151, and the second retainer 152 are configured so as not to separate. The pitch diameter of the ball set in the row of the first balls 141 formed by the plurality of first balls 141 of the inner ring assembly 135 is the same as the pitch diameter of the balls in the row of the second balls 142 formed by the plurality of second balls 142. Smaller than the pitch diameter of the set. The diameter of the plurality of first balls 141 is smaller than the diameter of the plurality of second balls 142 . The outer ring 120 has a first outer ring raceway 121, a first inclined surface 123, a second inclined surface 124, and a second outer ring raceway 122 from the first side in the axial direction to the second side. and a third inclined surface 125 on the inner peripheral surface. The inner peripheral surface of the outer ring 120 expands from the first outer ring raceway 121 to the third inclined surface 125 without decreasing in diameter. The raceway contact diameter of the first outer ring raceway 121 is smaller than the raceway contact diameter of the second outer ring raceway 122 . Ball bearing 110 is formed by combining inner ring assembly 135 and outer ring 120 . A plurality of first balls 141 are arranged to roll on the first outer ring raceway 121 . A plurality of second balls 142 are arranged to roll on the second outer ring raceway 122 . The nominal contact point of the first inner ring raceway 131 is located on the second axial side of the nominal contact point of the first outer ring raceway 121 . The nominal contact point of the second inner ring raceway 132 is located on the second axial side of the nominal contact point of the second outer ring raceway 122 . The first inclined surface 123 is formed on the inner peripheral surface of the outer ring 120 on the second side in the axial direction of the first outer ring raceway 121 and has a diameter that increases from the first side in the axial direction toward the second side. It is a conical surface that The second inclined surface 124 is formed on the second axial side of the first inclined surface 123 on the inner peripheral surface of the outer ring 120 and on the first axial side of the second outer ring raceway 122, It is a conical surface that expands in diameter from a first axial side toward a second axial side. A third inclined surface 125 is formed on the inner peripheral surface of the outer ring 120 on the axial second side of the second outer ring raceway 122 , adjoins the front surface of the outer ring 120 , and extends from the axial first side to the third axial side. It is a conical surface that expands toward the side of 2.
　このような構成の玉軸受１１０では、図１４に示すように、外輪１２０を内輪組立体１３５へ組み付ける際に、外輪１２０の中心軸Ｃ１０２が内輪組立体１３５の中心軸Ｃ１０３に対して傾いていると、第１の玉１４１が第１の傾斜面１２３と第１の内輪軌道１３１とに強く挟まれて接触して第１の玉１４１がすべることができず、スムーズに組付けできない（傾いた状態で組付けられずに止まってしまう）場合があった。このような場合において、内輪組立体１３５に外輪１２０を無理に押し込むと、第１の玉１４１が外輪１２０に噛み込んで、第１の玉１４１が傷つく場合があった。 In the ball bearing 110 having such a configuration, as shown in FIG. 14, when the outer ring 120 is assembled to the inner ring assembly 135, the central axis C102 of the outer ring 120 is inclined with respect to the central axis C103 of the inner ring assembly 135. As a result, the first ball 141 is strongly sandwiched between the first inclined surface 123 and the first inner ring raceway 131 and contacts, preventing the first ball 141 from sliding and assembling it smoothly. There was a case where it stopped without being assembled in a state). In such a case, if the outer ring 120 is forcibly pushed into the inner ring assembly 135, the first ball 141 may be caught in the outer ring 120 and the first ball 141 may be damaged.
　本開示は、玉軸受において、内輪組立体に対する外輪の組付け性を向上させ、玉軸受の損傷を抑制することを目的とする。 An object of the present disclosure is to improve the assembling property of the outer ring to the inner ring assembly and to suppress damage to the ball bearing in the ball bearing.
＜本開示の発明の効果＞
　本開示の玉軸受によれば、内輪組立体に対する外輪の組付け性を向上させ、玉軸受の損傷を抑制することができる。 <Effects of the Invention of the Present Disclosure>
According to the ball bearing of the present disclosure, it is possible to improve the assembling properties of the outer ring with respect to the inner ring assembly and suppress damage to the ball bearing.
＜本開示の発明の実施形態の概要＞
　以下、本開示の発明の実施形態の概要を列記して説明する。 <Summary of Embodiments of the Invention of the Present Disclosure>
An overview of the embodiments of the present disclosure will be described below by listing them.
　（１）本開示の玉軸受は、内輪組立体と、外輪と、を備え、前記内輪組立体は、内輪と、複数の第１の玉と、複数の第２の玉と、第１の保持器と、第２の保持器と、を備え、前記内輪は、軸方向の第１の側に第１の内輪軌道と、前記第１の内輪軌道の軸方向の第２の側に第２の内輪軌道と、を外周面に有し、前記第１の内輪軌道の軌道接触直径は、前記第２の内輪軌道の軌道接触直径よりも小さく、前記複数の第１の玉は、前記第１の内輪軌道に転動可能に配置され、前記第１の保持器は、複数の第１のポケットを有し、前記複数の第１の玉は、前記第１のポケットに摺動可能に配置され、前記複数の第２の玉は、前記第２の内輪軌道に転動可能に配置され、前記第２の保持器は、複数の第２のポケットを有し、前記複数の第２の玉は、前記第２のポケットに摺動可能に配置され、前記内輪と、前記複数の第１の玉と、前記複数の第２の玉と、前記第１の保持器と、前記第２の保持器と、が分離しないよう構成され、前記内輪組立体の、前記複数の第１の玉が構成する当該第１の玉の列の玉セットのピッチ径は、前記複数の第２の玉が構成する当該第２の玉の列の玉セットのピッチ径よりも小さく、前記外輪は、軸方向の第１の側から第２の側に向かって、第１の外輪軌道と、第１の傾斜面と、第２の傾斜面と、第２の外輪軌道と、を内周面に有し、前記外輪の内周面は、前記第１の外輪軌道から前記第２の外輪軌道まで直径が縮小することなく拡大し、前記第１の外輪軌道の軌道接触直径は、前記第２の外輪軌道の軌道接触直径よりも小さく、前記複数の第１の玉の直径は、前記複数の第２の玉の直径よりも小さく、前記複数の第１の玉は、前記第１の外輪軌道に転動可能に配置され、前記複数の第２の玉は、前記第２の外輪軌道に転動可能に配置され、前記第１の内輪軌道の呼び接触点は、前記第１の外輪軌道の呼び接触点より軸方向の第２の側に位置し、前記第２の内輪軌道の呼び接触点は、前記第２の外輪軌道の呼び接触点より軸方向の第２の側に位置し、前記第１の傾斜面は、前記外輪の内周面における前記第１の外輪軌道の軸方向の第２の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面であり、前記第２の傾斜面は、前記外輪の内周面における前記第１の傾斜面の軸方向の第２の側であって前記第２の外輪軌道の軸方向の第１の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面であり、前記外輪の中心軸を含む断面において前記第１の傾斜面と前記外輪の中心軸とがなす第１の劣角が、前記外輪の中心軸を含む断面において前記第２の傾斜面と前記外輪の中心軸とがなす第２の劣角よりも小さく、かつ、前記複数の第１の玉を前記第１の内輪軌道に配置し接触させた時に、前記複数の第１の玉の各第１の玉の中心が第１の大円上にあり、前記第１の玉の直径の半分を第１の小円の半径である第１の小半径とし、前記第１の玉の列の玉セットのピッチ径の半分を前記第１の大円の半径である第１の大半径とするトーラスを第１の仮想トーラスと、定義し、前記複数の第２の玉を前記第２の内輪軌道に配置し接触させた時に、前記複数の第２の玉の各第２の玉の中心が第２の大円上にあり、前記第２の玉の直径の半分を第２の小円の半径である第２の小半径とし、前記第２の玉の列の玉セットのピッチ径の半分を前記第２の大円の半径である第２の大半径とするトーラスを第２の仮想トーラスと、定義し、軸受中心軸を含む断面において、径方向の第１の側と径方向の第１の側とは周方向に１８０°反対側である径方向の第２の側とを定義し、径方向の第２の側の前記第２の大円を第１の端点とし、径方向の第１の側の前記第１の大円と径方向の第２の側の前記第２の大円とを通る直線と径方向の第１の側の前記第１の仮想トーラスの径方向の第１の側の表面との交点を第２の端点とし、前記第１の端点と前記第２の端点とを結ぶ線分を第１の線分とし、径方向の第１の側の前記第１の傾斜面の最も軸方向の第２の側を第３の端点とし、前記第１の端点と前記第３の端点とを結ぶ線分を第２の線分とし、径方向の第１の側の前記第１の傾斜面上にあり前記第１の端点から最も距離の小さい点を第４の端点とし、前記第１の端点と前記第４の端点とを結ぶ線分を第３の線分とし、前記第１の線分の長さが、前記第２の線分の長さよりも大きい、又は、前記第１の線分の長さが、前記第２の線分の長さよりも小さく、かつ、前記第３の線分の長さよりも小さい。 (1) A ball bearing of the present disclosure comprises an inner ring assembly and an outer ring, the inner ring assembly comprising an inner ring, a plurality of first balls, a plurality of second balls, and a first retainer. and a second retainer, wherein the inner ring has a first inner ring raceway on a first axial side and a second inner ring raceway on a second axial side of the first inner ring raceway. an inner ring raceway on an outer peripheral surface, the raceway contact diameter of the first inner ring raceway being smaller than the raceway contact diameter of the second inner ring raceway, and the plurality of first balls rollingly disposed on an inner ring raceway, the first retainer having a plurality of first pockets, the plurality of first balls slidably disposed in the first pockets; The plurality of second balls are arranged to be able to roll on the second inner ring raceway, the second retainer has a plurality of second pockets, and the plurality of second balls are: slidably disposed in the second pocket, the inner ring, the plurality of first balls, the plurality of second balls, the first retainer, and the second retainer; are configured not to separate, and the pitch diameter of the ball set in the first row of balls formed by the plurality of first balls of the inner ring assembly is equal to the pitch diameter of the ball set formed by the plurality of second balls. smaller than the pitch diameter of the ball set of the second row of balls, the outer ring has, from the first side in the axial direction toward the second side, a first outer ring raceway, a first inclined surface; The inner peripheral surface of the outer ring has a second inclined surface and a second outer ring raceway, and the inner peripheral surface of the outer ring does not decrease in diameter from the first outer ring raceway to the second outer ring raceway. The raceway contact diameter of the first outer ring raceway is smaller than the raceway contact diameter of the second outer ring raceway, and the diameter of the plurality of first balls is smaller than the diameter of the plurality of second balls. the plurality of first balls are arranged so as to be able to roll on the first outer ring raceway; the plurality of second balls are arranged so as to be able to roll on the second outer ring raceway; The nominal contact point of the first inner ring raceway is located on the second side in the axial direction from the nominal contact point of the first outer ring raceway, and the nominal contact point of the second inner ring raceway is located on the second outer ring. positioned on the second side in the axial direction from the nominal contact point of the raceway, the first inclined surface being formed on the second side in the axial direction of the first outer ring raceway on the inner peripheral surface of the outer ring, It is an inclined surface that expands in diameter from a first side toward a second side in the axial direction, and the second inclined surface is the second inclined surface in the axial direction of the first inclined surface on the inner peripheral surface of the outer ring. is formed on the first side in the axial direction of the second outer ring raceway and is an inclined surface that expands in diameter from the first side to the second side in the axial direction, and is the center of the outer ring A first minor angle formed by the first inclined surface and the central axis of the outer ring in a cross section containing the axis is equal to a first minor angle formed by the second inclined surface and the central axis of the outer ring in a cross section containing the central axis of the outer ring. The center of each first ball of the plurality of first balls is smaller than the second minor angle formed and when the plurality of first balls are arranged on the first inner ring raceway and brought into contact with each other. On the first great circle, half the diameter of the first ball is the radius of the first minor circle, the first minor radius being the radius of the first minor circle, and half the pitch diameter of the ball set of the first row of balls. is the radius of the first great circle, the torus is defined as the first virtual torus, and the plurality of second balls are arranged and brought into contact with the second inner ring raceway Sometimes, the center of each second ball of said plurality of second balls is on a second great circle, and half the diameter of said second ball is the radius of a second minor circle. A second virtual torus is defined as a torus having a radius and a half of the pitch diameter of the ball set of the second ball row as the second major radius, which is the radius of the second great circle, and the bearing center In a cross section that includes the axis, a radial first side and a radial second side that is 180° circumferentially opposite the radial first side are defined, and a radial second side A straight line passing through the first great circle on the first side in the radial direction and the second great circle on the second side in the radial direction and the diameter Let the intersection of the first side of the direction of the first virtual torus with the surface of the first side in the radial direction be the second end point, and let the line segment connecting the first end point and the second end point be A first line segment is defined as a first line segment, a second side of the first inclined surface on a first side in a radial direction is defined as a third end point, and the first end point and the third end point are defined as The line segment connecting the A line segment connecting the end point and the fourth end point is defined as a third line segment, and the length of the first line segment is greater than the length of the second line segment, or the first line The length of the minute is smaller than the length of the second line segment and smaller than the length of the third line segment.
　このような構成の玉軸受では、内輪組立体に対する外輪の組付け性を向上させ、玉軸受の損傷を抑制することができる。 With a ball bearing having such a configuration, it is possible to improve the assembling properties of the outer ring with respect to the inner ring assembly and to suppress damage to the ball bearing.
　（２）本開示の玉軸受は、好ましくは、前記外輪は、内周面に軸方向の第１の側から第２の側に向かって前記第１の外輪軌道と、前記第１の傾斜面と、前記第２の傾斜面と、前記第２の外輪軌道と、さらに第３の傾斜面を有し、前記外輪の内周面は、前記第１の外輪軌道から前記第３の傾斜面まで直径が縮小することなく拡大し、前記第１の劣角が、前記外輪の中心軸を含む断面において前記第３の傾斜面と前記外輪の中心軸とがなす第３の劣角よりも小さい。 (2) In the ball bearing of the present disclosure, preferably, the outer ring has the first outer ring raceway and the first inclined surface extending from the first side in the axial direction to the second side on the inner peripheral surface. , the second inclined surface, the second outer ring raceway, and a third inclined surface, and the inner peripheral surface of the outer ring extends from the first outer ring raceway to the third inclined surface. The diameter is enlarged without being reduced, and the first minor angle is smaller than the third minor angle formed by the third inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring.
　（３）本開示の玉軸受は、好ましくは、前記複数の第２の玉と、前記外輪の軸方向の第２の側の正面を含み当該外輪の中心軸に垂直な仮想平面とが、軸方向において重なっている。 (3) In the ball bearing of the present disclosure, preferably, the plurality of second balls and an imaginary plane including the front face of the second side in the axial direction of the outer ring and perpendicular to the central axis of the outer ring Overlapping in direction.
＜本開示の発明の実施形態の詳細＞
　以下、本開示の発明の実施形態を説明する。 <Details of Embodiments of Invention of Present Disclosure>
Embodiments of the present disclosure will be described below.
〔玉軸受について〕
　図１は、第１実施形態に係る玉軸受の全体構成を示す断面図である。図１に示す玉軸受１０は、複列玉軸受のアンギュラ玉軸受であって、各玉の列の軸受中心軸と作用線との劣角を同じ方向にし、各玉の列の玉セットのピッチ径を異ならせ、単列玉軸受のアンギュラ玉軸受よりも大きなアキシアル荷重を負荷できる玉軸受である。このような玉軸受は、タンデム形と称される。玉軸受１０は、例えば、自動車等に搭載されるデファレンシャルギヤ装置に用いられる軸受装置である差動機構（ギヤ機構）を構成するピニオン軸をケースに対して回転自在に支持する用途に使用される。玉軸受１０は、内輪組立体３５と、外輪２０と、を備える。以下の説明において、玉軸受１０の中心軸は、中心軸Ｃ１という。同様に、外輪２０の中心軸は、中心軸Ｃ２といい、内輪３０の中心軸は、中心軸Ｃ３という。外輪２０の中心軸Ｃ２と内輪３０の中心軸Ｃ３とは、内輪組立体３５と外輪２０とを組み合せた状態にある玉軸受１０の中心軸Ｃ１と一致する。以下の説明では、玉軸受１０の中心軸Ｃ１に沿った一の方向を軸方向の第１の側と称し、玉軸受１０の中心軸に沿った軸方向の第１の側とは１８０°反対側の方向を軸方向の第２の側と称する。また、以下の説明では、玉軸受１０の中心軸Ｃ１を含む断面において、中心軸Ｃ１に垂直な一の方向を径方向の第１の側と称し、中心軸Ｃ１に垂直な径方向の第１の側とは１８０°反対側の方向を径方向の第２の側と称する。 [About ball bearings]
FIG. 1 is a cross-sectional view showing the overall configuration of a ball bearing according to the first embodiment. The ball bearing 10 shown in FIG. 1 is a double-row angular contact ball bearing in which the minor angles between the bearing central axis and the line of action of each row of balls are set in the same direction, and the pitches of the ball sets of each row of balls are equal to each other. This is a ball bearing with different diameters that can handle a greater axial load than a single-row angular contact ball bearing. Such ball bearings are called tandem type. The ball bearing 10 is used, for example, to rotatably support a pinion shaft constituting a differential mechanism (gear mechanism), which is a bearing device used in a differential gear device mounted on an automobile or the like, with respect to a case. . The ball bearing 10 has an inner ring assembly 35 and an outer ring 20 . In the following description, the central axis of the ball bearing 10 will be referred to as central axis C1. Similarly, the central axis of the outer ring 20 is called central axis C2, and the central axis of the inner ring 30 is called central axis C3. The central axis C2 of the outer ring 20 and the central axis C3 of the inner ring 30 coincide with the central axis C1 of the ball bearing 10 in which the inner ring assembly 35 and the outer ring 20 are combined. In the following description, one direction along the central axis C1 of the ball bearing 10 is referred to as a first axial side, and is 180° opposite to the first axial side along the central axis of the ball bearing 10. The side direction is referred to as the axial second side. Further, in the following description, in a cross section including the central axis C1 of the ball bearing 10, one direction perpendicular to the central axis C1 is referred to as a radial first side. The direction 180° opposite to the side of is referred to as a second side in the radial direction.
（内輪組立体）
　図２は、内輪組立体を示す断面図である。内輪組立体３５は、内輪３０と、複数の第１の玉４１と、複数の第２の玉４２と、第１の保持器５１と、第２の保持器５２と、を備える。 (Inner ring assembly)
FIG. 2 is a cross-sectional view showing the inner ring assembly. The inner ring assembly 35 includes an inner ring 30 , a plurality of first balls 41 , a plurality of second balls 42 , a first retainer 51 and a second retainer 52 .
　図２に示す内輪３０は、高炭素クロム軸受鋼や炭素鋼、合金鋼等の鋼材でできている。内輪３０は、円筒状である。内輪３０は、軸方向の第１の側から第２の側に向けて、第１の肩と、第１の内輪軌道３１と、第２の肩と、第２の内輪軌道３２と、第３の肩と、を外周面に有する。第１の肩は、外周面が円筒面である。第１の内輪軌道３１は、後述する第１の玉４１の直径の半分より少し大きい溝半径を有する軌道溝である。第２の肩は、外周面が軸方向の第１の側から第２の側に向けて直径が拡大する円すい面とそれに続く円筒面である。第２の内輪軌道３２は、後述する第２の玉４２の直径の半分より少し大きい溝半径を有する軌道溝である。第３の肩は、外周面が円筒面である。第１の内輪軌道３１の軌道接触直径は、第２の内輪軌道３２の軌道接触直径よりも小さい。第１の肩の直径は、第１の内輪軌道３１の軌道接触直径よりも大きく、第２の肩の直径よりも小さい。第２の肩の直径は、第２の内輪軌道３２の直径よりも大きく、第３の肩の直径よりも小さい。第１の玉４１は、高炭素クロム軸受鋼等の鋼材でできている。第２の玉４２は、高炭素クロム軸受鋼等の鋼材でできている。第１の玉４１の直径は、第２の玉４２の直径よりも小さい。 The inner ring 30 shown in FIG. 2 is made of steel such as high-carbon chromium bearing steel, carbon steel, or alloy steel. The inner ring 30 is cylindrical. The inner ring 30 has a first shoulder, a first inner ring raceway 31, a second shoulder, a second inner ring raceway 32, a third inner ring raceway 32, and a third inner ring raceway 31 from the first side in the axial direction toward the second side. and a shoulder on the outer peripheral surface. The first shoulder has a cylindrical outer peripheral surface. The first inner ring raceway 31 is a raceway groove having a groove radius slightly larger than half the diameter of a first ball 41 to be described later. The second shoulder is a conical surface followed by a cylindrical surface whose outer peripheral surface increases in diameter from the first axial side to the second axial side. The second inner ring raceway 32 is a raceway groove having a groove radius slightly larger than half the diameter of a second ball 42 to be described later. The third shoulder has a cylindrical outer peripheral surface. The raceway contact diameter of the first inner ring raceway 31 is smaller than the raceway contact diameter of the second inner ring raceway 32 . The diameter of the first shoulder is larger than the raceway contact diameter of the first inner ring raceway 31 and smaller than the diameter of the second shoulder. The diameter of the second shoulder is larger than the diameter of the second inner ring raceway 32 and smaller than the diameter of the third shoulder. The first ball 41 is made of steel such as high carbon chromium bearing steel. The second ball 42 is made of steel such as high carbon chromium bearing steel. The diameter of the first ball 41 is smaller than the diameter of the second ball 42 .
　第１の保持器５１は、環状に形成されている。第１の保持器５１は、第１の環状体５１ａと、第２の環状体５１ｂと、複数の第１の柱５１ｃとを有する。第１の環状体５１ａは、複数の第１の柱５１ｃの軸方向の第１の側にある。第２の環状体５１ｂは、複数の第１の柱５１ｃの軸方向の第２の側にある。複数の第１の柱５１ｃは、第１の環状体５１ａに第１の環状体５１ａの軸方向の第２の側につながる。複数の第１の柱５１ｃは、第２の環状体５１ｂに第２の環状体５１ｂの軸方向の第１の側につながる。複数の第１の柱５１ｃは、第１の環状体５１ａの周方向に等間隔で配置される。第１の環状体５１ａの外周面の直径は、第２の環状体５１ｂの外周面の直径よりも小さい。第１の環状体５１ａの内周面の直径は、第２の環状体５１ｂの内周面の直径よりも小さい。第１の環状体５１ａと第２の環状体５１ｂと周方向に隣り合う第１の柱５１ｃとにより囲まれている領域が、第１の玉４１を保持する複数の第１のポケット５３を構成する。第１の保持器５１の複数の第１のポケット５３の径方向の外側の開口の内接円の直径は、第１の玉４１の直径よりも小さい。第１の保持器５１は、ポリアミド樹脂、ポリフェニレンサルファイド樹脂、フェノール樹脂等の合成樹脂製である。 The first retainer 51 is formed in an annular shape. The first retainer 51 has a first annular body 51a, a second annular body 51b, and a plurality of first pillars 51c. The first annular body 51a is on the first axial side of the plurality of first posts 51c. The second annular body 51b is on the second axial side of the plurality of first posts 51c. A plurality of first posts 51c connect to the first annular body 51a on a second axial side of the first annular body 51a. A plurality of first posts 51c connect to the second annular body 51b on a first axial side of the second annular body 51b. The plurality of first columns 51c are arranged at regular intervals in the circumferential direction of the first annular body 51a. The diameter of the outer peripheral surface of the first annular body 51a is smaller than the diameter of the outer peripheral surface of the second annular body 51b. The diameter of the inner peripheral surface of the first annular body 51a is smaller than the diameter of the inner peripheral surface of the second annular body 51b. A region surrounded by the first annular body 51a, the second annular body 51b, and the first pillars 51c adjacent in the circumferential direction forms a plurality of first pockets 53 that hold the first balls 41. do. The diameter of the inscribed circle of the radially outer openings of the plurality of first pockets 53 of the first retainer 51 is smaller than the diameter of the first balls 41 . The first retainer 51 is made of synthetic resin such as polyamide resin, polyphenylene sulfide resin, or phenol resin.
　第２の保持器５２は、環状に形成されている。第２の保持器５２は、第３の環状体５２ｂと、第４の環状体５２ａと、複数の第２の柱５２ｃとを有する。第３の環状体５２ｂは、複数の第２の柱５２ｃの軸方向の第１の側にある。第４の環状体５２ａは、複数の第２の柱５２ｃの軸方向の第２の側にある。複数の第２の柱５２ｃは、第３の環状体５２ｂに第３の環状体５２ｂの軸方向の第２の側につながる。複数の第２の柱５２ｃは、第４の環状体５２ａに第４の環状体５２ａの軸方向の第１の側につながる。複数の第２の柱５２ｃは、第３の環状体５２ｂの周方向に等間隔で配置される。第３の環状体５２ｂの外周面の直径は、第４の環状体５２ａの外周面の直径よりも小さい。第３の環状体５２ｂの内周面の直径は、第４の環状体５２ａの内周面の直径よりも小さい。第３の環状体５２ｂと第４の環状体５２ａと周方向に隣り合う第２の柱５２ｃとにより囲まれている領域が、第２の玉４２を保持する複数の第２のポケット５４を構成する。第２の保持器５２の複数の第２のポケット５４の径方向の外側の開口の内接円の直径は、第２の玉４２の直径よりも小さい。第２の保持器５２は、ポリアミド樹脂、ポリフェニレンサルファイド樹脂、フェノール樹脂等の合成樹脂製である。 The second retainer 52 is formed in an annular shape. The second retainer 52 has a third annular body 52b, a fourth annular body 52a, and a plurality of second posts 52c. The third annular body 52b is on the first axial side of the plurality of second posts 52c. The fourth annular body 52a is on the second axial side of the plurality of second posts 52c. A plurality of second posts 52c connect to the third annular body 52b on a second axial side of the third annular body 52b. A plurality of second posts 52c connect to the fourth annular body 52a on a first axial side of the fourth annular body 52a. The plurality of second columns 52c are arranged at regular intervals in the circumferential direction of the third annular body 52b. The diameter of the outer peripheral surface of the third annular body 52b is smaller than the diameter of the outer peripheral surface of the fourth annular body 52a. The diameter of the inner peripheral surface of the third annular body 52b is smaller than the diameter of the inner peripheral surface of the fourth annular body 52a. A region surrounded by the third annular body 52b, the fourth annular body 52a, and the second pillars 52c adjacent in the circumferential direction forms a plurality of second pockets 54 that hold the second balls 42. do. The diameter of the inscribed circle of the radially outer openings of the plurality of second pockets 54 of the second retainer 52 is smaller than the diameter of the second balls 42 . The second retainer 52 is made of synthetic resin such as polyamide resin, polyphenylene sulfide resin, or phenol resin.
　図２に示すように、第１の玉４１の列を構成する複数の第１の玉４１は、内輪３０の第１の内輪軌道３１に転動可能に配置される。複数の第１の玉４１は、第１の保持器５１の複数の第１のポケット５３に摺動可能に配置される。第１のポケット５３は、周方向に沿って複数形成されており、これにより、第１の保持器５１は、複数の第１の玉４１を周方向に沿って等間隔で保持することができる。第１の保持器５１の複数の第１のポケット５３の径方向の外側の開口の内接円の直径は、第１の玉４１の直径よりも小さいので、第１の玉４１は、第１の保持器５１の第１のポケット５３から径方向の外側に脱落しない。また、第１の肩の外周面の円筒面の直径は、第１の内輪軌道３１の軌道接触直径よりも大きい。また、第２の肩の外周面の円すい面の最小の直径は、第１の内輪軌道３１の軌道接触直径よりも大きい。このため、複数の第１の玉４１をそれぞれ第１の保持器５１の各第１のポケット５３に配置して第１の内輪軌道３１に配置したとき、内輪３０と、複数の第１の玉４１と、第１の保持器５１と、は分離しない。 As shown in FIG. 2, the plurality of first balls 41 forming the row of the first balls 41 are arranged to roll on the first inner ring raceway 31 of the inner ring 30 . The plurality of first balls 41 are slidably arranged in the plurality of first pockets 53 of the first retainer 51 . A plurality of first pockets 53 are formed along the circumferential direction so that the first retainer 51 can hold the plurality of first balls 41 at regular intervals along the circumferential direction. . Since the diameter of the inscribed circle of the radially outer openings of the plurality of first pockets 53 of the first retainer 51 is smaller than the diameter of the first balls 41, the first balls 41 do not drop radially outward from the first pocket 53 of the retainer 51 of the . Also, the diameter of the cylindrical surface of the outer peripheral surface of the first shoulder is larger than the raceway contact diameter of the first inner ring raceway 31 . Also, the minimum diameter of the conical surface of the outer peripheral surface of the second shoulder is larger than the raceway contact diameter of the first inner ring raceway 31 . Therefore, when the plurality of first balls 41 are arranged in the respective first pockets 53 of the first retainer 51 and arranged on the first inner ring raceway 31, the inner ring 30 and the plurality of first balls 41 and the first retainer 51 are not separated.
　第２の玉４２の列を構成する複数の第２の玉４２は、内輪３０の第２の内輪軌道３２に転動可能に配置される。複数の第２の玉４２は、第２の保持器５２の複数の第２のポケット５４に摺動可能に配置される。第２のポケット５４は、周方向に沿って複数形成されており、これにより、第２の保持器５２は、複数の第２の玉４２を周方向に沿って等間隔で保持することができる。第２の保持器５２の複数の第２のポケット５４の径方向の外側の開口の内接円の直径は、第２の玉４２の直径よりも小さいので、第２の玉４２は、第２の保持器５２の第２のポケット５４から径方向の外側に脱落しない。また、第２の肩の外周面の円筒面の直径は、第２の内輪軌道３２の軌道接触直径よりも大きい。また、第３の肩の外周面の円筒面の直径は、第２の内輪軌道３２の軌道接触直径よりも大きい。このため、複数の第２の玉４２をそれぞれ第２の保持器５２の各第２のポケット５４に配置して第２の内輪軌道３２に配置したとき、内輪３０と、複数の第２の玉４２と、第２の保持器５２と、は分離しない。 A plurality of second balls 42 forming a row of second balls 42 are arranged to roll on the second inner ring raceway 32 of the inner ring 30 . A plurality of second balls 42 are slidably disposed in a plurality of second pockets 54 of the second retainer 52 . A plurality of second pockets 54 are formed along the circumferential direction so that the second retainer 52 can hold the plurality of second balls 42 at regular intervals along the circumferential direction. . Since the diameter of the inscribed circle of the radially outer openings of the plurality of second pockets 54 of the second retainer 52 is smaller than the diameter of the second balls 42, the second balls 42 from the second pocket 54 of the retainer 52 in the radial direction. Also, the diameter of the cylindrical surface of the outer peripheral surface of the second shoulder is larger than the raceway contact diameter of the second inner ring raceway 32 . Also, the diameter of the cylindrical surface of the outer peripheral surface of the third shoulder is larger than the raceway contact diameter of the second inner ring raceway 32 . Therefore, when the plurality of second balls 42 are arranged in the respective second pockets 54 of the second retainer 52 and arranged on the second inner ring raceway 32, the inner ring 30 and the plurality of second balls 42 and the second retainer 52 are not separated.
　図２に示すように、内輪組立体３５は、内輪３０と、複数の第１の玉４１と、複数の第２の玉４２と、第１の保持器５１と、第２の保持器５２と、が分離しないように構成される。換言すると、玉軸受１０から外輪２０を取り外したものが、内輪組立体３５である。内輪組立体３５の、複数の第１の玉４１が構成する第１の玉４１の列の玉セットのピッチ径は、複数の第２の玉４２が構成する第２の玉４２の列の玉セットのピッチ径よりも小さい。 As shown in FIG. 2, the inner ring assembly 35 includes an inner ring 30, a plurality of first balls 41, a plurality of second balls 42, a first retainer 51, and a second retainer 52. , are configured so that they do not separate. In other words, the inner ring assembly 35 is obtained by removing the outer ring 20 from the ball bearing 10 . The pitch diameter of the ball set in the row of the first balls 41 formed by the plurality of first balls 41 of the inner ring assembly 35 is the same as the pitch diameter of the balls in the row of the second balls 42 formed by the plurality of second balls 42. Smaller than the pitch diameter of the set.
　図３に示すように、説明の便宜上、第１の仮想トーラスＴ１及び第２の仮想トーラスＴ２を規定する。第１の仮想トーラスＴ１は、第１の内輪軌道３１に転動可能に配置された複数の第１の玉４１の転動領域を表す仮想の立体形状である。第１の仮想トーラスＴ１は、内輪組立体３５と外輪２０とを組み付けた時に第１の内輪軌道３１に、各第１の玉４１が配置され接触された時の、各第１の玉４１の中心を含む断面の外形である第１の小円ＳＣ１の半径を第１の小半径Ｓｒ１とし、各第１の玉４１の中心を結ぶ仮想円である第１の大円ＢＣ１の半径を第１の大半径Ｂｒ１として規定される。換言すると、第１の小半径Ｓｒ１は、第１の玉４１の半径であり、第１の玉４１の直径の半分であり、第１の大半径Ｂｒ１は、複数の第１の玉４１によって構成されている第１の玉４１の列の玉セットのピッチ径の半分である。複数の第１の玉４１の各第１の玉４１の中心は第１の大円ＢＣ１上に位置する。なお、本説明では、第１の内輪軌道３１に配置された第１の玉４１を基準として第１の仮想トーラスＴ１を規定しているが、第１の仮想トーラスＴ１は、内輪組立体３５と外輪２０とを組み付けた時に第１の外輪軌道２１に、各第１の玉４１が配置され接触された時の、第１の玉４１を基準として規定してもよい。 As shown in FIG. 3, for convenience of explanation, a first virtual torus T1 and a second virtual torus T2 are defined. The first virtual torus T1 is a virtual three-dimensional shape that represents the rolling area of the plurality of first balls 41 that are rotatably arranged on the first inner ring raceway 31 . The first virtual torus T1 is the position of each first ball 41 when each first ball 41 is arranged and contacted with the first inner ring raceway 31 when the inner ring assembly 35 and the outer ring 20 are assembled. The radius of the first small circle SC1, which is the outer shape of the cross section including the center, is defined as the first small radius Sr1, and the radius of the first large circle BC1, which is the imaginary circle connecting the centers of the first balls 41, is defined as the first small radius Sr1. is defined as the major radius Br1 of In other words, the first small radius Sr1 is the radius of the first balls 41 and is half the diameter of the first balls 41, and the first large radius Br1 is composed of the plurality of first balls 41. It is half the pitch diameter of the set of balls in the row of the first balls 41 that are set. The center of each first ball 41 of the plurality of first balls 41 is positioned on the first great circle BC1. In this description, the first virtual torus T1 is defined with reference to the first balls 41 arranged on the first inner ring raceway 31, but the first virtual torus T1 is the inner ring assembly 35 and The first balls 41 when the first balls 41 are arranged and contacted with the first outer ring raceway 21 when the outer ring 20 is assembled may be defined as a reference.
　第２の仮想トーラスＴ２は、第２の内輪軌道３２に転動可能に配置された複数の第２の玉４２の転動領域を表す仮想の立体形状である。第２の仮想トーラスＴ２は、内輪組立体３５と外輪２０とを組み付けた時に第２の内輪軌道３２に、各第２の玉４２が配置され接触された時の、各第２の玉４２の中心を含む断面の外形である第２の小円ＳＣ２の半径を第２の小半径Ｓｒ２とし、各第２の玉４２の中心を結ぶ仮想円である第２の大円ＢＣ２の半径を第２の大半径Ｂｒ２として規定される。換言すると、第２の小半径Ｓｒ２は、第２の玉４２の半径であり、第２の玉４２の直径の半分であり、第２の大半径Ｂｒ２は、複数の第２の玉４２によって構成されている第２の玉４２の列の玉セットのピッチ径の半分である。複数の第２の玉４２の各第２の玉４２の中心は第２の大円ＢＣ２上に位置する。なお、本説明では、第２の内輪軌道３２に配置された第２の玉４２を基準として第２の仮想トーラスＴ２を規定しているが、第２の仮想トーラスＴ２は、内輪組立体３５と外輪２０とを組み付けた時に第２の外輪軌道２２に、各第２の玉４２が配置され接触された時の、第２の玉４２を基準として規定してもよい。 The second virtual torus T2 is a virtual three-dimensional shape that represents the rolling area of the plurality of second balls 42 that are rollably arranged on the second inner ring raceway 32 . The second virtual torus T2 is the position of each second ball 42 when each second ball 42 is arranged and comes into contact with the second inner ring raceway 32 when the inner ring assembly 35 and the outer ring 20 are assembled. The radius of the second small circle SC2, which is the outer shape of the cross section including the center, is defined as the second small radius Sr2, and the radius of the second large circle BC2, which is the imaginary circle connecting the centers of the second balls 42, is defined as the second small radius Sr2. is defined as the major radius Br2 of In other words, the second minor radius Sr2 is the radius of the second balls 42 and is half the diameter of the second balls 42, and the second major radius Br2 is composed of the plurality of second balls 42. It is half the pitch diameter of the set of balls in the second row of balls 42 being set. The center of each second ball 42 of the plurality of second balls 42 is positioned on the second great circle BC2. In this description, the second virtual torus T2 is defined with reference to the second balls 42 arranged on the second inner ring raceway 32. However, the second virtual torus T2 is the inner ring assembly 35. The second balls 42 may be defined as a reference when the second balls 42 are arranged and contacted with the second outer ring raceway 22 when the outer ring 20 is assembled.
　図２に示すように、内輪組立体３５について、説明の便宜上、第１の直線Ｌ１を規定する。第１の直線Ｌ１は、内輪３０の中心軸Ｃ３を含む断面において、中心軸Ｃ３と、径方向の第１の側の第１の大円ＢＣ１と、径方向の第２の側の第２の大円ＢＣ２と、に交差する直線である。径方向の第１の側は、内輪３０の中心軸Ｃ３を含む断面における一つの径方向の方向で、径方向の第２の側は、内輪３０の中心軸Ｃ３を含む断面における径方向の第１の側とは内輪３０の中心軸Ｃ３を中心に周方向に１８０°反対側の径方向の方向である。 As shown in FIG. 2, for the inner ring assembly 35, a first straight line L1 is defined for convenience of explanation. The first straight line L1 extends across the central axis C3, the first great circle BC1 on the first radial side, and the second great circle BC1 on the second radial side in a cross section including the central axis C3 of the inner ring 30. It is a straight line that intersects with the great circle BC2. The first radial side is one radial direction in a cross section including the central axis C3 of the inner ring 30, and the second radial side is the second radial direction in a cross section including the central axis C3 of the inner ring 30. The 1 side is the radial direction opposite to the center axis C3 of the inner ring 30 by 180° in the circumferential direction.
　図２に示すように、内輪組立体３５について、説明の便宜上、点ａ及び点ｂを規定する。点ａ（第１の端点）は、内輪３０の中心軸Ｃ３を含む断面において、第１の直線Ｌ１と、径方向の第２の側の第２の大円ＢＣ２との交点である。点ａ（第１の端点）は、第２の玉４２の中心をこの中心軸Ｃ３を含む断面上に示した時の第２の玉４２の中心である。点ｂ（第２の端点）は、内輪３０の中心軸Ｃ３を含む断面において、第１の直線Ｌ１と、径方向の第１の側の第１の仮想トーラスＴ１の径方向の第１の側の表面との交点である。以下の説明では、点ａ（第１の端点）及び点ｂ（第２の端点）を端点とする線分を第１の線分ａｂと称する。第１の線分ａｂは、第１の直線Ｌ１の一部分である。内輪組立体３５の周方向において、点ａ及び点ｂの位相は１８０°異なっている。 As shown in FIG. 2, for the inner ring assembly 35, points a and b are defined for convenience of explanation. A point a (first end point) is the intersection of the first straight line L1 and the second great circle BC2 on the second side in the radial direction in a cross section including the center axis C3 of the inner ring 30 . A point a (first end point) is the center of the second ball 42 when the center of the second ball 42 is shown on the cross section including this central axis C3. The point b (second end point) is the first straight line L1 and the first radial side of the first imaginary torus T1 on the cross section including the central axis C3 of the inner ring 30. is the intersection with the surface of In the following description, a line segment whose endpoints are the point a (first endpoint) and the point b (second endpoint) will be referred to as a first line segment ab. The first line segment ab is a portion of the first straight line L1. In the circumferential direction of the inner ring assembly 35, points a and b are out of phase by 180°.
（外輪の詳細形状）
　図４は、第１実施形態に係る外輪を示す断面図である。図５は、外輪２０の内周面に形成された各傾斜面を示す断面図である。外輪２０は、高炭素クロム軸受鋼や炭素鋼、合金鋼等の鋼材でできている。外輪２０は、軸方向の第１の側から第２の側に向かって、第４の肩と、第１の外輪軌道２１と、第１の傾斜面２３と、第２の傾斜面２４と、第２の外輪軌道２２と、第３の傾斜面２５と、を内周面に有する。外輪２０の内周面は、第１の外輪軌道２１から第３の傾斜面２５まで直径が縮小することなく拡大する。第１の外輪軌道２１の軌道接触直径は、第２の外輪軌道２２の軌道接触直径よりも小さい。 (Detailed shape of outer ring)
FIG. 4 is a cross-sectional view showing the outer ring according to the first embodiment. FIG. 5 is a cross-sectional view showing each inclined surface formed on the inner peripheral surface of the outer ring 20. As shown in FIG. The outer ring 20 is made of steel such as high-carbon chromium bearing steel, carbon steel, or alloy steel. The outer ring 20 has, from the axial first side to the second side, a fourth shoulder, a first outer ring raceway 21, a first inclined surface 23, a second inclined surface 24, It has a second outer ring raceway 22 and a third inclined surface 25 on the inner peripheral surface. The inner peripheral surface of the outer ring 20 expands from the first outer ring raceway 21 to the third inclined surface 25 without decreasing in diameter. The raceway contact diameter of the first outer ring raceway 21 is smaller than the raceway contact diameter of the second outer ring raceway 22 .
　第１の傾斜面２３は、外輪２０の内周面における第１の外輪軌道２１の軸方向の第２の側に形成され、軸方向の第１の側から第２の側に向かって拡径する円すい面である。第２の傾斜面２４は、外輪２０の内周面における第１の傾斜面２３の軸方向の第２の側であって第２の外輪軌道２２の軸方向の第１の側に形成され、軸方向の第１の側から第２の側に向かって拡径する円すい面である。第３の傾斜面２５は、外輪２０の内周面における第２の外輪軌道２２の軸方向の第２の側に形成され、外輪２０の正面に隣接し、軸方向の第１の側から第２の側に向かって拡径する円すい面である。第２の傾斜面２４の軸方向の長さは、第１の傾斜面２３の軸方向の長さの１／１０～１／２が好ましい。第３の傾斜面２５の軸方向の長さは、第１の傾斜面２３の軸方向の長さの１／１０～１／２が好ましい。 The first inclined surface 23 is formed on the inner peripheral surface of the outer ring 20 on the second side in the axial direction of the first outer ring raceway 21 and has a diameter that increases from the first side in the axial direction toward the second side. It is a conical surface that The second inclined surface 24 is formed on the second axial side of the first inclined surface 23 on the inner peripheral surface of the outer ring 20 and on the first axial side of the second outer ring raceway 22, It is a conical surface that expands in diameter from a first axial side toward a second axial side. The third inclined surface 25 is formed on the inner peripheral surface of the outer ring 20 on the axial second side of the second outer ring raceway 22 , adjoins the front surface of the outer ring 20 , and extends from the axial first side to the third axial side. It is a conical surface that expands toward the side of 2. The axial length of the second inclined surface 24 is preferably 1/10 to 1/2 of the axial length of the first inclined surface 23 . The axial length of the third inclined surface 25 is preferably 1/10 to 1/2 of the axial length of the first inclined surface 23 .
　外輪２０の中心軸Ｃ２を含む断面において、第１の傾斜面２３と外輪２０の中心軸Ｃ２（図５においては、外輪２０の中心軸Ｃ２を中心とする円筒面）とがなす第１の劣角θ１は、外輪２０の中心軸Ｃ２を含む断面において第２の傾斜面２４と外輪２０の中心軸Ｃ２（図５においては、外輪２０の中心軸Ｃ２を中心とする円筒面）とがなす第２の劣角θ２よりも小さい。外輪２０の中心軸Ｃ２を含む断面において、第１の劣角θ１は、第３の傾斜面２５と外輪２０の中心軸Ｃ２（図５においては、外輪２０の中心軸Ｃ２を中心とする円筒面）とがなす第３の劣角θ３よりも小さい。第１の劣角θ１は、１２°以下が好ましい。第２の劣角θ２は、２５°以上７５°以下が好ましい。第３の劣角θ３は、２５°以上７５°以下が好ましい。 In a cross section including the central axis C2 of the outer ring 20, a first inferiority plane formed by the first inclined surface 23 and the central axis C2 of the outer ring 20 (in FIG. 5, a cylindrical surface centered on the central axis C2 of the outer ring 20). The angle θ1 is the angle between the second inclined surface 24 and the central axis C2 of the outer ring 20 (in FIG. 5, a cylindrical surface centered on the central axis C2 of the outer ring 20) in a cross section including the central axis C2 of the outer ring 20. less than the minor angle θ2 of 2. In a cross section including the central axis C2 of the outer ring 20, the first minor angle θ1 is between the third inclined surface 25 and the central axis C2 of the outer ring 20 (in FIG. ) is smaller than the third minor angle θ3 formed by The first minor angle θ1 is preferably 12° or less. The second minor angle θ2 is preferably 25° or more and 75° or less. The third minor angle θ3 is preferably 25° or more and 75° or less.
　図４に示すように、外輪２０について、説明の便宜上、第２の直線Ｌ２を規定する。図４では、外輪２０に第１の仮想トーラスＴ１及び第２の仮想トーラスＴ２を配置している。第１の仮想トーラスＴ１は、内輪組立体３５と外輪２０とを組み付けた時の第１の外輪軌道２１に配置された複数の第１の玉４１の中心が第１の大円ＢＣ１上に一致するよう配置している。第２の仮想トーラスＴ２は、内輪組立体３５と外輪２０とを組み付けた時の第２の外輪軌道２２に配置された複数の第２の玉４２の中心が第２の大円ＢＣ２上に一致するよう配置している。第２の直線Ｌ２は、外輪２０の中心軸Ｃ２を含む断面において、中心軸Ｃ２と、径方向の第２の側の第２の大円ＢＣ２と、径方向の第１の側の第１の傾斜面２３の最も軸方向の第２の側と、に交差する直線である。 As shown in FIG. 4, for the outer ring 20, a second straight line L2 is defined for convenience of explanation. In FIG. 4 , a first virtual torus T1 and a second virtual torus T2 are arranged on the outer ring 20 . In the first virtual torus T1, the centers of the plurality of first balls 41 arranged on the first outer ring raceway 21 when the inner ring assembly 35 and the outer ring 20 are assembled are aligned on the first great circle BC1. It is arranged to In the second virtual torus T2, the centers of the plurality of second balls 42 arranged on the second outer ring raceway 22 when the inner ring assembly 35 and the outer ring 20 are assembled are aligned on the second great circle BC2. It is arranged to The second straight line L2 is defined in a cross section including the central axis C2 of the outer ring 20, along the central axis C2, the second great circle BC2 on the second radial side, and the first great circle BC2 on the first radial side. It is a straight line that intersects the most axial second side of the inclined surface 23 .
　図４に示すように、外輪２０について、説明の便宜上、点ｃ、点ｄを規定する。点ｃは、外輪２０の中心軸Ｃ２を含む断面において、第２の直線Ｌ２と径方向の第２の側の第２の大円ＢＣ２（図３参照）とが交差する点である。点ｃは、第２の玉４２の中心をこの中心軸Ｃ２を含む断面上に示した時の第２の玉４２の中心である。なお、点ｃは、玉軸受１０の中心軸Ｃ１（Ｃ２、Ｃ３）を含む断面において、点ａと一致する。このため本説明では、点ａと同様に点ｃを「第１の端点」と称する。点ｄ（第３の端点）は、外輪２０の中心軸Ｃ２を含む断面において、第２の直線Ｌ２と、第１の傾斜面２３の最も軸方向の第２の側とが交差する点である。以下の説明では、点ｃ（第１の端点）と点ｄ（第３の端点）とを端点とする線分を第２の線分ｃｄと称する。第２の線分ｃｄは、第２の直線Ｌ２の一部分である。外輪２０の周方向において、点ｃ及び点ｄの位相は１８０°異なっている。点ｃの位相は、点ａの位相と同じであり、点ｄの位相は、点ｂの位相と同じである。 As shown in FIG. 4, for the outer ring 20, points c and d are defined for convenience of explanation. A point c is a point where the second straight line L2 and the second great circle BC2 (see FIG. 3) on the second side in the radial direction intersect in a cross section including the central axis C2 of the outer ring 20 . A point c is the center of the second ball 42 when the center of the second ball 42 is shown on the cross section including the central axis C2. Note that the point c coincides with the point a in a cross section including the central axis C1 (C2, C3) of the ball bearing 10. As shown in FIG. Therefore, in this description, the point c is referred to as the "first end point" as well as the point a. A point d (third end point) is a point at which the second straight line L2 intersects the second most axial side of the first inclined surface 23 in a cross section including the central axis C2 of the outer ring 20. . In the following description, a line segment whose endpoints are point c (first endpoint) and point d (third endpoint) will be referred to as a second line segment cd. The second line segment cd is part of the second straight line L2. In the circumferential direction of the outer ring 20, the points c and d are out of phase by 180°. The phase of point c is the same as the phase of point a, and the phase of point d is the same as the phase of point b.
（第１実施形態に係る玉軸受）
　図１に示すように、玉軸受１０は、内輪組立体３５と外輪２０とを組み合わせてなる。複数の第１の玉４１は、第１の外輪軌道２１に転動可能に配置される。複数の第２の玉４２は、第２の外輪軌道２２に転動可能に配置される。第１の内輪軌道３１の呼び接触点は、第１の外輪軌道２１の呼び接触点より軸方向の第２の側に位置する。第２の内輪軌道３２の呼び接触点は、第２の外輪軌道２２の呼び接触点より軸方向の第２の側に位置する。内輪３０の軸方向の第１の側の側面が内輪３０の正面であり、内輪３０の軸方向の第２の側の側面が内輪３０の背面である。外輪２０の軸方向の第１の側の側面が外輪２０の背面であり、外輪２０の軸方向の第２の側の側面が外輪２０の正面である。 (Ball bearing according to the first embodiment)
As shown in FIG. 1 , the ball bearing 10 is formed by combining an inner ring assembly 35 and an outer ring 20 . A plurality of first balls 41 are arranged to roll on the first outer ring raceway 21 . A plurality of second balls 42 are arranged to roll on the second outer ring raceway 22 . The nominal contact point of the first inner ring raceway 31 is located on the second axial side of the nominal contact point of the first outer ring raceway 21 . The nominal contact point of the second inner ring raceway 32 is located on the second axial side of the nominal contact point of the second outer ring raceway 22 . The side surface on the first axial side of the inner ring 30 is the front surface of the inner ring 30 , and the side surface on the second axial side of the inner ring 30 is the rear surface of the inner ring 30 . The side surface of the outer ring 20 on the first side in the axial direction is the back side of the outer ring 20 , and the side surface on the second side in the axial direction of the outer ring 20 is the front side of the outer ring 20 .
　図６は、第１実施形態に係る玉軸受の内輪組立体に対する外輪の組付状況を示す断面図である。図６には、第１実施形態に係る玉軸受１０である第１の玉軸受１０Ａを示している。第１の玉軸受１０Ａは、第１実施形態に係る外輪２０である第１の外輪２０Ａを有している。なお、本説明では、第１の外輪２０Ａにおける第１の外輪軌道２１を第１の外輪軌道２１Ａ、第２の外輪軌道２２を第２の外輪軌道２２Ａ、第１の傾斜面２３を第１の傾斜面２３Ａ、第２の傾斜面２４を第２の傾斜面２４Ａ、第３の傾斜面２５を第３の傾斜面２５Ａ、とそれぞれ称する。本説明では、第１の玉軸受１０Ａを単に玉軸受１０Ａとも称し、第１の外輪２０Ａを単に外輪２０Ａとも称する。 FIG. 6 is a cross-sectional view showing how the outer ring is assembled to the inner ring assembly of the ball bearing according to the first embodiment. FIG. 6 shows a first ball bearing 10A, which is the ball bearing 10 according to the first embodiment. The first ball bearing 10A has a first outer ring 20A which is the outer ring 20 according to the first embodiment. In this description, the first outer ring raceway 21 in the first outer ring 20A is referred to as the first outer ring raceway 21A, the second outer ring raceway 22 as the second outer ring raceway 22A, and the first inclined surface 23 as the first outer ring raceway 21A. The inclined surface 23A and the second inclined surface 24 are called a second inclined surface 24A, and the third inclined surface 25 is called a third inclined surface 25A, respectively. In this description, 10 A of 1st ball bearings are also simply called 10 A of ball bearings, and 20 A of 1st outer rings are also simply called 20 A of outer rings.
　第１の玉軸受１０Ａでは、線分ａｂの長さが、線分ｃｄの長さに比べて大きい。 In the first ball bearing 10A, the length of line segment ab is greater than the length of line segment cd.
　図６に示す第１の外輪２０Ａ及び内輪組立体３５は、第１の外輪２０Ａの中心軸Ｃ２及び内輪３０の中心軸Ｃ３を含む断面において、点ａ（第１の端点）と点ｃ（第１の端点）とが一致する状態で配置されている。この状態から点ａ（第１の端点）を通る第２の大円ＢＣ２の接線を中心として内輪組立体３５を回転させた場合、第１の線分ａｂの長さが、線分ｃｄの長さに比べて大きいため、径方向の第１の側の第１の玉４１は、第１の傾斜面２３Ａに入り込むことができない。つまり、第１の玉軸受１０Ａは、第１の外輪２０Ａの中心軸Ｃ２に対して、内輪３０の中心軸Ｃ３が傾斜している状態では、第１の外輪２０Ａと内輪組立体３５とを組付けることが困難である。このため、内輪組立体３５に第１の外輪２０Ａを組み付ける際に、第１の玉４１が第１の傾斜面２３Ａに接して引っ掛かる可能性が低い。つまり、このような構成の第１の玉軸受１０Ａでは、第１の外輪２０Ａの中心軸Ｃ２に対して、内輪３０の中心軸Ｃ３が傾斜している状態では、第１の外輪２０Ａ及び内輪組立体３５を組付けることが困難である。また、このような構成では、第１の外輪２０Ａを内輪組立体３５に無理に押し込む必要が生じにくく、径方向の第１の側の第１の玉４１が第１の傾斜面２３Ａに擦れて傷つく可能性を低く抑えることができる。本開示では、外輪２０と内輪組立体３５とを組み付ける際に第１の玉４１を傷つける可能性が低い場合に、組付け性が優れていると評価する。このため、第１の玉軸受１０Ａは、組付け性に優れていると評価できる。 The first outer ring 20A and inner ring assembly 35 shown in FIG. 6 have a point a (first end point) and a point c (second 1) are aligned with each other. When the inner ring assembly 35 is rotated about the tangent line of the second great circle BC2 passing through the point a (first end point) from this state, the length of the first line segment ab becomes the length of the line segment cd. , the first ball 41 on the first side in the radial direction cannot enter the first inclined surface 23A. In other words, in the first ball bearing 10A, the first outer ring 20A and the inner ring assembly 35 are combined in a state where the central axis C3 of the inner ring 30 is inclined with respect to the central axis C2 of the first outer ring 20A. difficult to attach. Therefore, when assembling the first outer ring 20A to the inner ring assembly 35, there is a low possibility that the first ball 41 will come into contact with the first inclined surface 23A and be caught. That is, in the first ball bearing 10A having such a configuration, when the central axis C3 of the inner ring 30 is inclined with respect to the central axis C2 of the first outer ring 20A, the first outer ring 20A and the inner ring group Assembling the solid 35 is difficult. In addition, in such a configuration, it is difficult to force the first outer ring 20A into the inner ring assembly 35, and the first ball 41 on the first side in the radial direction rubs against the first inclined surface 23A. You can reduce your chances of getting hurt. In the present disclosure, when the possibility of damaging the first ball 41 when assembling the outer ring 20 and the inner ring assembly 35 is low, the assemblability is evaluated to be excellent. Therefore, it can be evaluated that the first ball bearing 10A is excellent in assembling performance.
（第２実施形態に係る玉軸受）
　図７は、第２実施形態に係る玉軸受の全体構成を示す断面図である。図８は、第２実施形態に係る外輪を示す断面図である。図９は、第２実施形態に係る玉軸受の内輪組立体に対する外輪の組付状況を示す断面図である。図７には、第２実施形態に係る玉軸受１０である第２の玉軸受１０Ｂを示している。第２の玉軸受１０Ｂは、第２実施形態に係る外輪２０である第２の外輪２０Ｂ（図８参照）を有している点で、第１の玉軸受１０Ａと異なっている。なお、本説明では、第２の外輪２０Ｂにおける第１の外輪軌道２１を第１の外輪軌道２１Ｂ、第２の外輪軌道２２を第２の外輪軌道２２Ｂ、第１の傾斜面２３を第１の傾斜面２３Ｂ、第２の傾斜面２４を第２の傾斜面２４Ｂ、第３の傾斜面２５を第３の傾斜面２５Ｂ、とそれぞれ称する。本説明では、第２の玉軸受１０Ｂを単に玉軸受１０Ｂとも称し、第１の外輪２０Ａを単に外輪２０Ｂとも称する。 (Ball bearing according to the second embodiment)
FIG. 7 is a cross-sectional view showing the overall configuration of a ball bearing according to the second embodiment. FIG. 8 is a cross-sectional view showing an outer ring according to the second embodiment. FIG. 9 is a cross-sectional view showing how the outer ring is attached to the inner ring assembly of the ball bearing according to the second embodiment. FIG. 7 shows a second ball bearing 10B, which is the ball bearing 10 according to the second embodiment. The second ball bearing 10B differs from the first ball bearing 10A in that it has a second outer ring 20B (see FIG. 8) which is the outer ring 20 according to the second embodiment. In this description, the first outer ring raceway 21 of the second outer ring 20B is referred to as the first outer ring raceway 21B, the second outer ring raceway 22 is referred to as the second outer ring raceway 22B, and the first inclined surface 23 is referred to as the first outer ring raceway 21B. The inclined surface 23B and the second inclined surface 24 are called a second inclined surface 24B, and the third inclined surface 25 is called a third inclined surface 25B. In this description, the second ball bearing 10B is also simply called the ball bearing 10B, and the first outer ring 20A is also simply called the outer ring 20B.
　第２の外輪２０Ｂについて、説明の便宜上、点ｅを規定する（図８参照）。点ｅ（第４の端点）は、第２の外輪２０Ｂの中心軸Ｃ２を含む断面において、径方向の第１の側の第１の傾斜面２３上に位置する点であって、点ｃ（第１の端点）との距離が最短となる点である。以下の説明では、点ｃ（第１の端点）と点ｅ（第４の端点）とを端点とする線分を第３の線分ｃｅと称する。外輪２０の周方向において、点ｃ及び点ｅの位相は１８０°異なっている。点ｅの位相は、点ｄの位相と同じである。 For the second outer ring 20B, a point e is defined for convenience of explanation (see FIG. 8). A point e (fourth end point) is a point located on the first inclined surface 23 on the first side in the radial direction in a cross section including the central axis C2 of the second outer ring 20B. 1st end point) is the shortest point. In the following description, a line segment having point c (first end point) and point e (fourth end point) as end points will be referred to as a third line segment ce. In the circumferential direction of the outer ring 20, the points c and e are out of phase by 180°. The phase of point e is the same as the phase of point d.
　第２の玉軸受１０Ｂでは、第１の線分ａｂの長さが、第２の線分ｃｄの長さに比べて小さく、かつ、第３の線分ｃｅの長さに比べて小さい。 In the second ball bearing 10B, the length of the first line segment ab is shorter than the length of the second line segment cd and shorter than the length of the third line segment ce.
　図９に示す第２の外輪２０Ｂ及び内輪組立体３５は、第２の外輪２０Ｂの中心軸Ｃ２及び内輪３０の中心軸Ｃ３を含む断面において、点ａ（第１の端点）と点ｃ（第１の端点）とが一致する状態で配置されている。この状態から点ａ（第１の端点）を通る第２の大円ＢＣ２の接線を中心として内輪組立体３５を回転させた場合、第１の玉４１は、第１の傾斜面２３Ｂに入り込むことはでき、かつ、第１の傾斜面２３Ｂを超えて、第１の外輪軌道２１Ｂに入り込むことができる。つまり、第２の玉軸受１０Ｂでは、内輪組立体３５に第２の外輪２０Ｂを組み付ける際に、第１の玉４１が第１の傾斜面２３Ｂに接して引っ掛かる可能性が低い。つまり、このような構成の第２の玉軸受１０Ｂでは、第２の外輪２０Ｂの中心軸Ｃ２に対して、内輪３０の中心軸Ｃ３が傾斜している状態で、第２の外輪２０Ｂ及び内輪組立体３５を組付けたとしても、引っ掛かることなく容易に組付けることができる。また、第２の外輪２０Ｂが内輪組立体３５に引っ掛かる可能性が低いため、第２の外輪２０Ｂを内輪組立体３５に無理に押し込む必要が生じにくく、第１の玉４１が第１の傾斜面２３Ｂに擦れて傷つく可能性を低く抑えることができる。このため、第２の玉軸受１０Ｂは、組付け性に優れていると評価できる。 The second outer ring 20B and inner ring assembly 35 shown in FIG. 9 have a point a (first end point) and a point c (second 1) are aligned with each other. When the inner ring assembly 35 is rotated about the tangent line of the second great circle BC2 passing through the point a (first end point) from this state, the first ball 41 enters the first inclined surface 23B. and can enter the first outer ring raceway 21B beyond the first inclined surface 23B. That is, in the second ball bearing 10B, when the second outer ring 20B is assembled to the inner ring assembly 35, the first balls 41 are less likely to be caught in contact with the first inclined surface 23B. That is, in the second ball bearing 10B having such a configuration, the second outer ring 20B and the inner ring assembly are arranged in a state in which the central axis C3 of the inner ring 30 is inclined with respect to the central axis C2 of the second outer ring 20B. Even if the three-dimensional body 35 is assembled, it can be easily assembled without being caught. In addition, since the possibility that the second outer ring 20B is caught by the inner ring assembly 35 is low, it is difficult to force the second outer ring 20B into the inner ring assembly 35. It is possible to reduce the possibility of being scratched by rubbing against 23B. Therefore, it can be evaluated that the second ball bearing 10B is excellent in assembling performance.
（比較例に係る玉軸受）
　図１０は、比較例に係る玉軸受の全体構成を示す断面図である。図１１は、比較例に係る外輪を示す断面図である。図１２は、比較例に係る玉軸受の内輪組立体に対する外輪の組付状況を示す断面図である。図１０に示す玉軸受６０は、外輪７０を有している点で、本開示の玉軸受１０と異なっている。なお、玉軸受６０は、本開示の玉軸受１０と共通する内輪組立体３５を備えている。以下の説明において、玉軸受６０の中心軸は中心軸Ｃ４という。同様に、外輪７０の中心軸は中心軸Ｃ５といい、内輪３０の中心軸は中心軸Ｃ３という。外輪７０の中心軸Ｃ５と内輪３０の中心軸Ｃ３とは、内輪組立体３５と外輪７０とを組み合せた状態にある玉軸受６０の中心軸Ｃ４と一致する。 (Ball bearing according to comparative example)
FIG. 10 is a cross-sectional view showing the overall configuration of a ball bearing according to a comparative example. FIG. 11 is a cross-sectional view showing an outer ring according to a comparative example. FIG. 12 is a cross-sectional view showing how the outer ring is attached to the inner ring assembly of the ball bearing according to the comparative example. A ball bearing 60 shown in FIG. 10 differs from the ball bearing 10 of the present disclosure in that it has an outer ring 70 . Note that the ball bearing 60 includes an inner ring assembly 35 in common with the ball bearing 10 of the present disclosure. In the following description, the central axis of the ball bearing 60 will be referred to as central axis C4. Similarly, the central axis of the outer ring 70 is called central axis C5, and the central axis of the inner ring 30 is called central axis C3. The central axis C5 of the outer ring 70 and the central axis C3 of the inner ring 30 coincide with the central axis C4 of the ball bearing 60 in which the inner ring assembly 35 and the outer ring 70 are combined.
　図１０及び図１１に示すように、外輪７０の内周面には、第１の外輪軌道７１及び第２の外輪軌道７２の他に、第１の傾斜面７３、第２の傾斜面７４、及び第３の傾斜面７５が形成されている。 As shown in FIGS. 10 and 11, the inner peripheral surface of the outer ring 70 has a first inclined surface 73, a second inclined surface 74, a first inclined surface 73, a second inclined surface 74, a first outer ring raceway 71 and a second outer ring raceway 72. and a third inclined surface 75 are formed.
　第１の傾斜面７３は、外輪７０の内周面における第１の外輪軌道７１の軸方向の第２の側に形成され、軸方向の第１の側から第２の側に向かって拡径する円すい面である。第２の傾斜面７４は、外輪７０の内周面における第１の傾斜面７３の軸方向の第２の側であって第２の外輪軌道７２の軸方向の第１の側に形成され、軸方向の第１の側から第２の側に向かって拡径する円すい面である。第３の傾斜面７５は、外輪７０の内周面における第２の外輪軌道７２の軸方向の第２の側に形成され、外輪７０の正面に隣接し、軸方向の第１の側から第２の側に向かって拡径する円すい面である。 The first inclined surface 73 is formed on the inner peripheral surface of the outer ring 70 on the second side in the axial direction of the first outer ring raceway 71 and has a diameter that increases from the first side in the axial direction toward the second side. It is a conical surface that The second inclined surface 74 is formed on the second axial side of the first inclined surface 73 on the inner peripheral surface of the outer ring 70 and on the first axial side of the second outer ring raceway 72, It is a conical surface that expands in diameter from a first axial side toward a second axial side. The third inclined surface 75 is formed on the inner peripheral surface of the outer ring 70 on the axial second side of the second outer ring raceway 72 , adjoins the front surface of the outer ring 70 , and extends from the axial first side to the third axial side. It is a conical surface that expands toward the side of 2.
　外輪７０の中心軸Ｃ５を含む断面において、第１の傾斜面７３と外輪７０の中心軸Ｃ５とがなす第１の劣角θ１０１は、外輪７０の中心軸Ｃ５を含む断面において第２の傾斜面７４と外輪７０の中心軸Ｃ５とがなす第２の劣角θ１０２よりも小さい。外輪７０の中心軸Ｃ５を含む断面において、第１の劣角θ１０１は、第３の傾斜面７５と外輪７０の中心軸Ｃ５とがなす第３の劣角θ１０３よりも小さい。 A first minor angle θ101 formed between the first inclined surface 73 and the central axis C5 of the outer ring 70 in the cross section including the central axis C5 of the outer ring 70 is the second inclined surface in the cross section including the central axis C5 of the outer ring 70. 74 and the central axis C5 of the outer ring 70 is smaller than the second minor angle θ102. In a cross section including central axis C5 of outer ring 70 , first minor angle θ101 is smaller than third minor angle θ103 formed by third inclined surface 75 and central axis C5 of outer ring 70 .
　外輪７０について、第２の外輪２０Ｂ（図８参照）と同様の点ｄ、点ｅを規定する（図１１参照）。 Regarding the outer ring 70, points d and e similar to those of the second outer ring 20B (see FIG. 8) are defined (see FIG. 11).
　玉軸受６０は、第１の線分ａｂの長さが、第２の線分ｃｄの長さに比べて小さく、かつ、第３の線分ｃｅの長さに比べて大きい。玉軸受６０は、このような寸法関係を有する点で、本開示の玉軸受１０（第１の玉軸受１０Ａ及び第２の玉軸受１０Ｂ）と異なっている。比較例に係る玉軸受６０は、本開示の玉軸受１０には含まれない。 In the ball bearing 60, the length of the first line segment ab is shorter than the length of the second line segment cd and longer than the length of the third line segment ce. The ball bearing 60 differs from the ball bearing 10 (the first ball bearing 10A and the second ball bearing 10B) of the present disclosure in that it has such a dimensional relationship. A ball bearing 60 according to a comparative example is not included in the ball bearing 10 of the present disclosure.
　図１２に示す外輪７０及び内輪組立体３５は、外輪７０の中心軸Ｃ５及び内輪３０の中心軸Ｃ３を含む断面において、点ａ（第１の端点）と点ｃ（第１の端点）とが一致する状態で配置されている。この状態から点ａ（第１の端点）を通る第２の大円ＢＣ２の接線を中心として内輪組立体３５を回転させた場合、径方向の第１の側の第１の玉４１は、第１の傾斜面７３に入り込むことはできるものの、第１の傾斜面７３を超えて、第１の外輪軌道７１に入り込むことができない。つまり、比較例に係る玉軸受６０では、内輪組立体３５に外輪７０を組み付ける際に、第１の玉４１が第１の傾斜面７３に接して引っ掛かる可能性がある。また、引っ掛かった状態の外輪７０を内輪組立体３５に無理に押し込んだ場合には、第１の玉４１が第１の傾斜面７３に擦れて傷つく可能性がある。このため、玉軸受６０は、組付け性が良くないと評価できる。 The outer ring 70 and the inner ring assembly 35 shown in FIG. 12 have a point a (first end point) and a point c (first end point) in a cross section including the central axis C5 of the outer ring 70 and the central axis C3 of the inner ring 30. are placed in a matching manner. When the inner ring assembly 35 is rotated about the tangent line of the second great circle BC2 passing through the point a (first end point) from this state, the first ball 41 on the first side in the radial direction Although it can enter the first inclined surface 73 , it cannot go over the first inclined surface 73 and enter the first outer ring raceway 71 . That is, in the ball bearing 60 according to the comparative example, when the outer ring 70 is assembled to the inner ring assembly 35, the first ball 41 may come into contact with the first inclined surface 73 and be caught. Further, if the outer ring 70 in the hooked state is forcibly pushed into the inner ring assembly 35, the first ball 41 may rub against the first inclined surface 73 and be damaged. For this reason, the ball bearing 60 can be evaluated as having poor assembling properties.
［実施形態の作用効果］
　以上に説明した実施形態における玉軸受１０Ａ、１０Ｂは、内輪組立体３５と、外輪２０Ａ、２０Ｂと、を備えている。内輪組立体３５は、内輪３０と、複数の第１の玉４１と、複数の第２の玉４２と、第１の保持器５１と、第２の保持器５２と、を備えている。内輪３０は、軸方向の第１の側に第１の内輪軌道３１と、第１の内輪軌道３１の軸方向の第２の側に第２の内輪軌道３２と、を外周面に有している。第１の内輪軌道３１の軌道接触直径は、第２の内輪軌道３２の軌道接触直径よりも小さい。複数の第１の玉４１は、第１の内輪軌道３１に転動可能に配置されている。第１の保持器５１は、複数の第１のポケット５３を有している。複数の第１の玉４１は、第１のポケット５３に摺動可能に配置されている。複数の第２の玉４２は、第２の内輪軌道３２に転動可能に配置されている。第２の保持器５２は、複数の第２のポケット５４を有している。複数の第２の玉４２は、第２のポケット５４に摺動可能に配置されている。内輪３０と、複数の第１の玉４１と、複数の第２の玉４２と、第１の保持器５１と、第２の保持器５２と、が分離しないよう構成されている。内輪組立体３５の、複数の第１の玉４１が構成する第１の玉４１の列の玉セットのピッチ径は、複数の第２の玉４２が構成する第２の玉４２の列の玉セットのピッチ径よりも小さい。外輪２０Ａ、２０Ｂは、軸方向の第１の側から第２の側に向かって第１の外輪軌道２１Ａ、２１Ｂと、第１の傾斜面２３Ａ、２３Ｂと、第２の傾斜面２４Ａ、２４Ｂと、第２の外輪軌道２２Ａ、２２Ｂと、を内周面に有している。外輪２０Ａ、２０Ｂの内周面は、第１の外輪軌道２１Ａ、２１Ｂから第２の外輪軌道２２Ａ、２２Ｂまで直径が縮小することなく拡大し、第１の外輪軌道２１Ａ、２１Ｂの軌道接触直径は、第２の外輪軌道２２Ａ、２２Ｂの軌道接触直径よりも小さい。複数の第１の玉４１の直径は、複数の第２の玉４２の直径よりも小さい。複数の第１の玉４１は、第１の外輪軌道２１Ａ、２１Ｂに転動可能に配置される。複数の第２の玉４２は、第２の外輪軌道２２Ａ、２２Ｂに転動可能に配置される。第１の内輪軌道３１の呼び接触点は、第１の外輪軌道２１Ａ、２１Ｂの呼び接触点より軸方向の第２の側に位置する。第２の内輪軌道３２の呼び接触点は、第２の外輪軌道２２Ａ、２２Ｂの呼び接触点より軸方向の第２の側に位置する。第１の傾斜面２３Ａ、２３Ｂは、外輪２０Ａ、２０Ｂの内周面における第１の外輪軌道２１Ａ、２１Ｂの軸方向の第２の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面である。第２の傾斜面２４Ａ、２４Ｂは、外輪２０Ａ、２０Ｂの内周面における第１の傾斜面２３Ａ、２３Ｂの軸方向の第２の側であって第２の外輪軌道２２Ａ、２２Ｂの軸方向の第１の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面である。外輪２０Ａ、２０Ｂの中心軸Ｃ２を含む断面において第１の傾斜面２３Ａ、２３Ｂと外輪２０Ａ、２０Ｂの中心軸Ｃ２とがなす第１の劣角θ１が、外輪２０Ａ、２０Ｂの中心軸Ｃ２を含む断面において第２の傾斜面２４Ａ、２４Ｂと外輪２０Ａ、２０Ｂの中心軸Ｃ２とがなす第２の劣角θ２よりも小さい。複数の第１の玉４１を第１の内輪軌道３１に配置し接触させた時に、複数の第１の玉４１の各第１の玉４１の中心が第１の大円ＢＣ１上にあり、第１の玉４１の直径の半分を第１の小円ＳＣ１の半径である第１の小半径Ｓｒ１とし、第１の玉４１の列の玉セットのピッチ径の半分を第１の大円ＢＣ１の半径である第１の大半径Ｂｒ１とするトーラスを第１の仮想トーラスＴ１と、定義する。複数の第２の玉４２を第２の内輪軌道３２に配置し接触させた時に、複数の第２の玉４２の各第２の玉４２の中心が第２の大円ＢＣ２上にあり、第２の玉４２の直径の半分を第２の小円ＳＣ２の半径である第２の小半径Ｓｒ２とし、第２の玉４２の列の玉セットのピッチ径の半分を第２の大円ＢＣ２の半径である第２の大半径Ｂｒ２とするトーラスを第２の仮想トーラスＴ２と、定義する。軸受中心軸Ｃ１を含む断面において、径方向の第１の側と径方向の第１の側とは周方向に１８０°反対側である径方向の第２の側とを定義し、径方向の第２の側の第２の大円ＢＣ２を第１の端点ａ、ｃとし、径方向の第１の側の第１の大円ＢＣ１と径方向の第２の側の第２の大円ＢＣ２とを通る第１の直線Ｌ１と径方向の第１の側の第１の仮想トーラスＴ１の径方向の第１の側の表面との交点を第２の端点ｂとし、第１の端点ａ、ｃと第２の端点ｂとを結ぶ線分を第１の線分ａｂとし、径方向の第１の側の第１の傾斜面２３Ａ、２３Ｂの最も軸方向の第２の側を第３の端点ｄとし、第１の端点ａ、ｃと第３の端点ｄとを結ぶ線分を第２の線分ｃｄとし、径方向の第１の側の第１の傾斜面２３Ａ、２３Ｂ上にあり第１の端点ａ、ｃから最も距離の小さい点を第４の端点ｅとし、第１の端点ａ、ｃと第４の端点ｅをと結ぶ線分を第３の線分ｃｅとする。玉軸受１０Ａ、１０Ｂでは、第１の線分ａｂの長さが第２の線分ｃｄの長さよりも大きい（外輪２０Ａの場合）、又は、第１の線分ａｂの長さが第２の線分ｃｄの長さよりも小さく、かつ、第１の線分ａｂの長さが第３の線分ｃｅの長さよりも小さい（外輪２０Ｂの場合）。 [Action and effect of the embodiment]
The ball bearings 10A, 10B in the embodiments described above include an inner ring assembly 35 and outer rings 20A, 20B. The inner ring assembly 35 includes an inner ring 30 , a plurality of first balls 41 , a plurality of second balls 42 , a first retainer 51 and a second retainer 52 . The inner ring 30 has a first inner ring raceway 31 on the first side in the axial direction and a second inner ring raceway 32 on the second side in the axial direction of the first inner ring raceway 31 on its outer peripheral surface. there is The raceway contact diameter of the first inner ring raceway 31 is smaller than the raceway contact diameter of the second inner ring raceway 32 . A plurality of first balls 41 are arranged to roll on the first inner ring raceway 31 . The first retainer 51 has a plurality of first pockets 53 . The plurality of first balls 41 are slidably arranged in the first pocket 53 . A plurality of second balls 42 are arranged to roll on the second inner ring raceway 32 . The second retainer 52 has a plurality of second pockets 54 . A plurality of second balls 42 are slidably disposed in the second pocket 54 . The inner ring 30, the plurality of first balls 41, the plurality of second balls 42, the first retainer 51, and the second retainer 52 are configured so as not to separate. The pitch diameter of the ball set in the row of the first balls 41 formed by the plurality of first balls 41 of the inner ring assembly 35 is the same as the pitch diameter of the balls in the row of the second balls 42 formed by the plurality of second balls 42. Smaller than the pitch diameter of the set. The outer rings 20A, 20B have first outer ring raceways 21A, 21B, first inclined surfaces 23A, 23B, and second inclined surfaces 24A, 24B from the first side in the axial direction to the second side. , and second outer ring raceways 22A and 22B on the inner peripheral surface. The inner peripheral surfaces of the outer rings 20A, 20B expand from the first outer ring raceways 21A, 21B to the second outer ring raceways 22A, 22B without decreasing in diameter, and the raceway contact diameters of the first outer ring raceways 21A, 21B are , is smaller than the raceway contact diameter of the second outer ring raceway 22A, 22B. The diameter of the plurality of first balls 41 is smaller than the diameter of the plurality of second balls 42 . A plurality of first balls 41 are arranged so as to be able to roll on the first outer ring raceways 21A and 21B. A plurality of second balls 42 are arranged so as to be able to roll on the second outer ring raceways 22A and 22B. The nominal contact point of the first inner ring raceway 31 is located on the second side in the axial direction from the nominal contact point of the first outer ring raceways 21A, 21B. The nominal contact point of the second inner ring raceway 32 is located on the second side in the axial direction from the nominal contact point of the second outer ring raceways 22A, 22B. The first inclined surfaces 23A, 23B are formed on the second side in the axial direction of the first outer ring raceways 21A, 21B on the inner peripheral surfaces of the outer rings 20A, 20B. It is an inclined surface that expands in diameter toward the side. The second inclined surfaces 24A, 24B are located on the second side in the axial direction of the first inclined surfaces 23A, 23B on the inner peripheral surfaces of the outer rings 20A, 20B and in the axial direction of the second outer ring raceways 22A, 22B. It is an inclined surface formed on the first side and increasing in diameter from the first side toward the second side in the axial direction. A first minor angle θ1 formed by the first inclined surfaces 23A, 23B and the central axis C2 of the outer rings 20A, 20B in a cross section including the central axis C2 of the outer rings 20A, 20B includes the central axis C2 of the outer rings 20A, 20B. It is smaller than the second minor angle θ2 formed by the second inclined surfaces 24A, 24B and the central axes C2 of the outer rings 20A, 20B in cross section. When the plurality of first balls 41 are arranged and brought into contact with the first inner ring raceway 31, the center of each first ball 41 of the plurality of first balls 41 is on the first great circle BC1, The half of the diameter of the first ball 41 is defined as the first small radius Sr1, which is the radius of the first small circle SC1, and the half of the pitch diameter of the ball set in the row of the first balls 41 is defined as the diameter of the first great circle BC1. A torus having a first major radius Br1, which is a radius, is defined as a first virtual torus T1. When the plurality of second balls 42 are arranged and brought into contact with the second inner ring raceway 32, the center of each second ball 42 of the plurality of second balls 42 is on the second great circle BC2, The second small radius Sr2, which is the radius of the second small circle SC2, is half the diameter of the second ball 42, and the half of the pitch diameter of the ball set in the row of the second balls 42 is the second great circle BC2. A torus having a second large radius Br2, which is a radius, is defined as a second virtual torus T2. In a cross section including the bearing central axis C1, a radial first side and a radial second side opposite to the radial first side by 180° in the circumferential direction are defined. With a second great circle BC2 on the second side as the first end points a, c, a first great circle BC1 on the first radial side and a second great circle BC2 on the second radial side and the surface of the first imaginary torus T1 on the first side in the radial direction. The line segment connecting c and the second end point b is defined as a first line segment ab, and the second most axial side of the first inclined surfaces 23A and 23B on the first side in the radial direction is defined as the third side. A line segment connecting the first end points a and c and the third end point d is defined as a second line segment cd, which lies on the first inclined surfaces 23A and 23B on the first side in the radial direction. A point closest to the first end points a and c is defined as a fourth end point e, and a line segment connecting the first end points a and c and the fourth end point e is defined as a third line segment ce. In the ball bearings 10A and 10B, the length of the first line segment ab is greater than the length of the second line segment cd (in the case of the outer ring 20A), or the length of the first line segment ab is greater than the length of the second line segment cd. It is smaller than the length of the line segment cd, and the length of the first line segment ab is smaller than the length of the third line segment ce (in the case of the outer ring 20B).
　このような構成の玉軸受１０Ａ、１０Ｂでは、内輪組立体３５に対して外輪２０を組み付ける際に、外輪２０の第１の傾斜面２３に第１の玉４１が接触することがなく、第１の傾斜面２３に第１の玉４１が接触した状態で外輪２０が引っ掛かって止まってしまうのを抑制することができる。このため、上記実施形態で示した玉軸受１０Ａ、１０Ｂによれば、内輪組立体３５に対する外輪２０の組付け性を向上させることができる。 In the ball bearings 10A and 10B having such a configuration, when the outer ring 20 is assembled to the inner ring assembly 35, the first balls 41 do not come into contact with the first inclined surface 23 of the outer ring 20. It is possible to prevent the outer ring 20 from being caught and stopped in a state where the first ball 41 is in contact with the inclined surface 23 of . Therefore, according to the ball bearings 10A and 10B shown in the above embodiment, it is possible to improve the assembling property of the outer ring 20 to the inner ring assembly 35 .
　また、玉軸受１０Ａ、１０Ｂにおいて、外輪２０Ａ、２０Ｂは、内周面に軸方向の第１の側から第２の側に向かって、第１の外輪軌道２１Ａ、２１Ｂと、第１の傾斜面２３Ａ、２３Ｂと、第２の傾斜面２４Ａ、２４Ｂと、第２の外輪軌道２２Ａ、２２Ｂと、さらに第３の傾斜面２５Ａ、２５Ｂを有する。外輪２０Ａ、２０Ｂの内周面は、第１の外輪軌道２１Ａ、２１Ｂから第３の傾斜面２５Ａ、２５Ｂまで直径が縮小することなく拡大する。玉軸受１０Ａ、１０Ｂでは、第１の劣角θ１が、外輪２０Ａ、２０Ｂの中心軸Ｃ２を含む断面において第３の傾斜面２５Ａ、２５Ｂと外輪２０Ａ、２０Ｂの中心軸Ｃ２とがなす第３の劣角θ３よりも小さい。このような構成の玉軸受１０Ａ、１０Ｂによれば、内輪組立体３５に対する外輪２０の組付け性を向上させることができる。 In the ball bearings 10A and 10B, the outer rings 20A and 20B are provided with first outer ring raceways 21A and 21B and first inclined surfaces on the inner peripheral surface from the first side toward the second side in the axial direction. 23A, 23B, second inclined surfaces 24A, 24B, second outer ring raceways 22A, 22B, and third inclined surfaces 25A, 25B. The inner peripheral surfaces of the outer rings 20A, 20B expand without decreasing in diameter from the first outer ring raceways 21A, 21B to the third inclined surfaces 25A, 25B. In the ball bearings 10A, 10B, the first minor angle θ1 is the third angle between the third inclined surfaces 25A, 25B and the central axes C2 of the outer rings 20A, 20B in the cross section containing the central axes C2 of the outer rings 20A, 20B. It is smaller than the minor angle θ3. According to the ball bearings 10A and 10B having such a configuration, it is possible to improve the assembling property of the outer ring 20 to the inner ring assembly 35 .
　また、玉軸受１０Ａ、１０Ｂは、複数の第２の玉４２と、外輪２０Ａ、２０Ｂの軸方向の第２の側の正面を含み当該外輪２０Ａ、２０Ｂの中心軸に垂直な仮想平面とが、軸方向において重なっている。この場合、外輪２０Ａ、２０Ｂから第２の玉４２の一部が径方向に露出する形態を有する玉軸受１０Ａ、１０Ｂについて、内輪組立体３５に対する外輪２０Ａ、２０Ｂの組付け性を向上させることができる。 In the ball bearings 10A and 10B, the plurality of second balls 42 and a virtual plane including the front surfaces of the second sides of the outer rings 20A and 20B in the axial direction and perpendicular to the central axes of the outer rings 20A and 20B are: They overlap in the axial direction. In this case, regarding the ball bearings 10A and 10B in which a part of the second balls 42 are radially exposed from the outer rings 20A and 20B, the assembly of the outer rings 20A and 20B to the inner ring assembly 35 can be improved. can.
　今回開示した実施形態はすべての点で例示であって制限的なものではない。本発明の権利範囲は、上述の実施形態に限定されるものではなく、請求の範囲に記載された構成と均等の範囲内でのすべての変更が含まれる。 The embodiments disclosed this time are illustrative in all respects and are not restrictive. The scope of rights of the present invention is not limited to the above-described embodiments, but includes all modifications within the scope of equivalents to the configurations described in the claims.
　１０、１０Ａ、１０Ｂ、６０、１１０、２１０：玉軸受
　２０、２０Ａ、２０Ｂ、７０、１２０、２２０：外輪
　２１、２１Ａ、２１Ｂ、７１、１２１、２２１：第１の外輪軌道
　２２、２２Ａ、２２Ｂ、７２、１２２、２２２：第２の外輪軌道
　２３、２３Ａ、２３Ｂ、７３、１２３：第１の傾斜面
　２４、２４Ａ、２４Ｂ、７４、１２４：第２の傾斜面
　２５、２５Ａ、２５Ｂ、７５、１２５：第３の傾斜面
　３０、１３０：内輪
　３１、１３１：第１の内輪軌道
　３２、１３２：第２の内輪軌道
　３５、１３５：内輪組立体
　４１、１４１：第１の玉
　４２、１４２：第２の玉
　５１：第１の保持器
　５２：第２の保持器
　５３：第１のポケット
　５４：第２のポケット
　θ１：第１の劣角
　θ２：第２の劣角
　θ３：第３の劣角
　Ｔ１：第１の仮想トーラス
　Ｔ２：第２の仮想トーラス
　ＳＣ１：第１の小円
　ＳＣ２：第２の小円
　ＢＣ１：第１の大円
　ＢＣ２：第２の大円
　Ｓｒ１：第１の小半径
　Ｓｒ２：第２の小半径
　Ｂｒ１：第１の大半径
　Ｂｒ２：第２の大半径
　Ｌ１：第１の直線
　ａ、ｃ：第１の端点
　ｂ：第２の端点
　ｄ：第３の端点
　ｅ：第４の端点
　ａｂ：第１の線分
　ｃｄ：第２の線分
　ｃｅ：第３の線分 10, 10A, 10B, 60, 110, 210: ball bearings 20, 20A, 20B, 70, 120, 220: outer rings 21, 21A, 21B, 71, 121, 221: first outer ring raceways 22, 22A, 22B, 72, 122, 222: Second outer ring raceway 23, 23A, 23B, 73, 123: First inclined surface 24, 24A, 24B, 74, 124: Second inclined surface 25, 25A, 25B, 75, 125 : third inclined surface 30, 130: inner ring 31, 131: first inner ring raceway 32, 132: second inner ring raceway 35, 135: inner ring assembly 41, 141: first ball 42, 142: second ball 51: first retainer 52: second retainer 53: first pocket 54: second pocket θ1: first minor angle θ2: second minor angle θ3: third minor angle T1 : First virtual torus T2: Second virtual torus SC1: First small circle SC2: Second small circle BC1: First great circle BC2: Second great circle Sr1: First small radius Sr2: second minor radius Br1: first major radius Br2: second major radius L1: first straight line a, c: first end point b: second end point d: third end point e: fourth end point end point ab: first line segment cd: second line segment ce: third line segment

Claims (3)

  1. 　内輪組立体と、外輪と、を備え、
    　前記内輪組立体は、内輪と、複数の第１の玉と、複数の第２の玉と、第１の保持器と、第２の保持器と、を備え、
    　前記内輪は、軸方向の第１の側に第１の内輪軌道と、前記第１の内輪軌道の軸方向の第２の側に第２の内輪軌道と、を外周面に有し、
    　前記第１の内輪軌道の軌道接触直径は、前記第２の内輪軌道の軌道接触直径よりも小さく、
    　前記複数の第１の玉は、前記第１の内輪軌道に転動可能に配置され、
    　前記第１の保持器は、複数の第１のポケットを有し、
    　前記複数の第１の玉は、前記第１のポケットに摺動可能に配置され、
    　前記複数の第２の玉は、前記第２の内輪軌道に転動可能に配置され、
    　前記第２の保持器は、複数の第２のポケットを有し、
    　前記複数の第２の玉は、前記第２のポケットに摺動可能に配置され、
    　前記内輪と、前記複数の第１の玉と、前記複数の第２の玉と、前記第１の保持器と、前記第２の保持器と、が分離しないよう構成され、
    　前記内輪組立体の、前記複数の第１の玉が構成する当該第１の玉の列の玉セットのピッチ径は、前記複数の第２の玉が構成する当該第２の玉の列の玉セットのピッチ径よりも小さく、
    　前記外輪は、軸方向の第１の側から第２の側に向かって、第１の外輪軌道と、第１の傾斜面と、第２の傾斜面と、第２の外輪軌道と、を内周面に有し、
    　前記外輪の内周面は、前記第１の外輪軌道から前記第２の外輪軌道まで直径が縮小することなく拡大し、
    　前記第１の外輪軌道の軌道接触直径は、前記第２の外輪軌道の軌道接触直径よりも小さく、
    　前記複数の第１の玉の直径は、前記複数の第２の玉の直径よりも小さく、
    　前記複数の第１の玉は、前記第１の外輪軌道に転動可能に配置され、前記複数の第２の玉は、前記第２の外輪軌道に転動可能に配置され、
    　前記第１の内輪軌道の呼び接触点は、前記第１の外輪軌道の呼び接触点より軸方向の第２の側に位置し、
    　前記第２の内輪軌道の呼び接触点は、前記第２の外輪軌道の呼び接触点より軸方向の第２の側に位置し、
    　前記第１の傾斜面は、前記外輪の内周面における前記第１の外輪軌道の軸方向の第２の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面であり、
    　前記第２の傾斜面は、前記外輪の内周面における前記第１の傾斜面の軸方向の第２の側であって前記第２の外輪軌道の軸方向の第１の側に形成され、軸方向の第１の側から第２の側に向かって拡径する傾斜面であり、
    　前記外輪の中心軸を含む断面において前記第１の傾斜面と前記外輪の中心軸とがなす第１の劣角が、前記外輪の中心軸を含む断面において前記第２の傾斜面と前記外輪の中心軸とがなす第２の劣角よりも小さく、かつ、
    　前記複数の第１の玉を前記第１の内輪軌道に配置し接触させた時に、前記複数の第１の玉の各第１の玉の中心が第１の大円上にあり、前記第１の玉の直径の半分を第１の小円の半径である第１の小半径とし、前記第１の玉の列の玉セットのピッチ径の半分を前記第１の大円の半径である第１の大半径とするトーラスを第１の仮想トーラスと、定義し、
    　前記複数の第２の玉を前記第２の内輪軌道に配置し接触させた時に、前記複数の第２の玉の各第２の玉の中心が第２の大円上にあり、前記第２の玉の直径の半分を第２の小円の半径である第２の小半径とし、前記第２の玉の列の玉セットのピッチ径の半分を前記第２の大円の半径である第２の大半径とするトーラスを第２の仮想トーラスと、定義し、
    　軸受中心軸を含む断面において、径方向の第１の側と径方向の第１の側とは周方向に１８０°反対側である径方向の第２の側とを定義し、
    　径方向の第２の側の前記第２の大円を第１の端点とし、
    　径方向の第１の側の前記第１の大円と径方向の第２の側の前記第２の大円とを通る直線と径方向の第１の側の前記第１の仮想トーラスの径方向の第１の側の表面との交点を第２の端点とし、
    　前記第１の端点と前記第２の端点とを結ぶ線分を第１の線分とし、
    　径方向の第１の側の前記第１の傾斜面の最も軸方向の第２の側を第３の端点とし、
    　前記第１の端点と前記第３の端点とを結ぶ線分を第２の線分とし、
    　径方向の第１の側の前記第１の傾斜面上にあり前記第１の端点から最も距離の小さい点を第４の端点とし、
    　前記第１の端点と前記第４の端点をと結ぶ線分を第３の線分とし、
    　前記第１の線分の長さが前記第２の線分の長さよりも大きい、
    　又は、
    　前記第１の線分の長さが前記第２の線分の長さよりも小さく、かつ、
    　前記第１の線分の長さが前記第３の線分の長さよりも小さい、玉軸受。     comprising an inner ring assembly and an outer ring,
    The inner ring assembly includes an inner ring, a plurality of first balls, a plurality of second balls, a first retainer, and a second retainer,
    the inner ring has a first inner ring raceway on a first side in the axial direction and a second inner ring raceway on the second side in the axial direction of the first inner ring raceway on the outer peripheral surface;
    The raceway contact diameter of the first inner ring raceway is smaller than the raceway contact diameter of the second inner ring raceway,
    The plurality of first balls are arranged so as to be able to roll on the first inner ring raceway,
    The first retainer has a plurality of first pockets,
    the plurality of first balls are slidably disposed in the first pocket;
    The plurality of second balls are arranged so as to be able to roll on the second inner ring raceway,
    the second retainer has a plurality of second pockets,
    the plurality of second balls are slidably disposed in the second pocket;
    The inner ring, the plurality of first balls, the plurality of second balls, the first retainer, and the second retainer are configured so as not to separate,
    The pitch diameter of the ball set of the first ball row composed of the plurality of first balls of the inner ring assembly is the ball of the second ball row composed of the plurality of second balls. smaller than the pitch diameter of the set,
    The outer ring has a first outer ring raceway, a first inclined surface, a second inclined surface, and a second outer ring raceway from the first axial side toward the second axial side. has on the peripheral surface,
    the inner peripheral surface of the outer ring expands from the first outer ring raceway to the second outer ring raceway without decreasing in diameter;
    The raceway contact diameter of the first outer ring raceway is smaller than the raceway contact diameter of the second outer ring raceway,
    the diameter of the plurality of first balls is smaller than the diameter of the plurality of second balls;
    The plurality of first balls are rollably arranged on the first outer ring raceway, the plurality of second balls are rollably arranged on the second outer ring raceway,
    the nominal contact point of the first inner ring raceway is located on the second side in the axial direction from the nominal contact point of the first outer ring raceway,
    the nominal contact point of the second inner ring raceway is located on the second side in the axial direction from the nominal contact point of the second outer ring raceway,
    The first inclined surface is formed on the inner peripheral surface of the outer ring on the second side in the axial direction of the first outer ring raceway, and the diameter increases from the first side in the axial direction toward the second side. is an inclined surface that
    The second inclined surface is formed on the second axial side of the first inclined surface on the inner peripheral surface of the outer ring and on the first axial side of the second outer ring raceway, an inclined surface that expands in diameter from the first side toward the second side in the axial direction;
    A first minor angle formed by the first inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring is such that a first minor angle between the second inclined surface and the outer ring in the cross section including the central axis of the outer ring is smaller than the second minor angle formed with the central axis, and
    When the plurality of first balls are arranged and brought into contact with the first inner ring raceway, the center of each first ball of the plurality of first balls is on the first great circle, and the first ball is located on the first great circle. A first minor radius that is the radius of the first minor circle is half of the diameter of the balls of the above, and half of the pitch diameter of the ball set of the first row of balls is the radius of the first major circle that is the radius of the first major circle. A torus with a major radius of 1 is defined as a first virtual torus,
    When the plurality of second balls are arranged and brought into contact with the second inner ring raceway, the center of each second ball of the plurality of second balls is on the second great circle, and the second ball is located on the second great circle. A second minor radius that is the radius of the second minor circle is half the diameter of the balls of the second row, and half of the pitch diameter of the ball set of the second row of balls is the radius of the second major circle that is the radius of the second major circle. A torus with a large radius of 2 is defined as a second virtual torus,
    In a cross section including the bearing center axis, defining a radial first side and a radial second side opposite to the radial first side by 180° in the circumferential direction,
    The second great circle on the second side in the radial direction is defined as a first end point,
    A straight line passing through the first great circle on the first radial side and the second great circle on the second radial side and the diameter of the first virtual torus on the first radial side Let the intersection with the surface on the first side of the direction be the second endpoint,
    A line segment connecting the first end point and the second end point is defined as a first line segment,
    The second most axial side of the first inclined surface on the first side in the radial direction is defined as a third end point,
    A line segment connecting the first end point and the third end point is defined as a second line segment,
    A point located on the first inclined surface on the first side in the radial direction and having the shortest distance from the first end point is defined as a fourth end point;
    A line segment connecting the first end point and the fourth end point is defined as a third line segment,
    the length of the first line segment is greater than the length of the second line segment;
    or
    The length of the first line segment is smaller than the length of the second line segment, and
    A ball bearing, wherein the length of the first line segment is smaller than the length of the third line segment.
  2. 　前記外輪は、内周面に軸方向の第１の側から第２の側に向かって、前記第１の外輪軌道と、前記第１の傾斜面と、前記第２の傾斜面と、前記第２の外輪軌道と、さらに第３の傾斜面を有し、
    　前記外輪の内周面は、前記第１の外輪軌道から前記第３の傾斜面まで直径が縮小することなく拡大し、
    　前記第１の劣角が、前記外輪の中心軸を含む断面において前記第３の傾斜面と前記外輪の中心軸とがなす第３の劣角よりも小さい、請求項1に記載の玉軸受。     The outer ring has the first outer ring raceway, the first inclined surface, the second inclined surface, and the 2 outer ring raceways and a third inclined surface,
    the inner peripheral surface of the outer ring expands from the first outer ring raceway to the third inclined surface without decreasing in diameter;
    2. The ball bearing according to claim 1, wherein the first minor angle is smaller than a third minor angle formed by the third inclined surface and the central axis of the outer ring in a cross section including the central axis of the outer ring.
  3. 　前記複数の第２の玉と、前記外輪の軸方向の第２の側の正面を含み当該外輪の中心軸に垂直な仮想平面とが、軸方向において重なっている、請求項１又は請求項２に記載の玉軸受。 Claim 1 or Claim 2, wherein the plurality of second balls and an imaginary plane including the front surface of the second axial side of the outer ring and perpendicular to the center axis of the outer ring axially overlap each other. The ball bearing described in .
PCT/JP2022/000639 2022-01-12 2022-01-12 Ball bearing WO2023135667A1 (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007278324A (en) * 2006-04-03 2007-10-25 Jtekt Corp Pinion shaft supporting double row rolling bearing and rolling bearing device equipped therewith
JP2014040870A (en) * 2012-08-23 2014-03-06 Nsk Ltd Tandem type double row angular ball bearing
KR20170131975A (en) * 2016-05-23 2017-12-01 주식회사 베어링아트 Tandem Angular Contact Ball Bearing And Assembling method thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007278324A (en) * 2006-04-03 2007-10-25 Jtekt Corp Pinion shaft supporting double row rolling bearing and rolling bearing device equipped therewith
JP2014040870A (en) * 2012-08-23 2014-03-06 Nsk Ltd Tandem type double row angular ball bearing
KR20170131975A (en) * 2016-05-23 2017-12-01 주식회사 베어링아트 Tandem Angular Contact Ball Bearing And Assembling method thereof

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