Rolling bearing and bearing device

Abstract

To provide a rolling bearing capable of preventing insufficient lubrication and abnormal temperature rise inside the bearing during high-speed rotation.SOLUTION: The rolling bearing comprises an outer ring fixed seal member 6 covering one end opening in the axial direction of a bearing space 3 leaving a first clearance 20 and an inner ring fixed seal member 7 covering the other end opening in the axial direction of the bearing space 3 leaving a second clearance 22, wherein the inner ring fixed seal member 7 is a metallic shield plate arranged so that a virtual line L obtained by extending the side surface outside in the axial direction of the inclined part 25 passes through the position of the radially inner end of the other end surface 1a in the axial direction of the outer ring 1.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rolling bearing in which the inside of the bearing is lubricated with oil supplied from outside the bearing while the bearing is rotating, and to a bearing device using such a rolling bearing. [Background technology]

[0002] BACKGROUND ART Rolling bearings are often used as bearings for supporting rotating shafts in automobiles, industrial machines, and the like (for example, Patent Documents 1 and 2).

[0003] The rolling bearings in Patent Documents 1 and 2 have an outer ring, an inner ring arranged radially inward of the outer ring, a plurality of rolling elements incorporated in an annular bearing space formed between the outer ring and the inner ring, and a cage that holds the plurality of rolling elements. Both of the rolling bearings in Patent Documents 1 and 2 are of the oil-lubricated type, in which oil supplied from outside the bearing is introduced into the bearing space while the bearing is rotating and the oil lubricates the inside of the bearing.

[0004] The rolling bearing in Patent Document 1 is a sealed type rolling bearing having a pair of seal members that cover the end openings on both axial sides of the bearing space. The seal members are provided with a filter portion that allows the passage of oil supplied from outside the bearing.

[0005] The rolling bearing in Patent Document 2 is an open-type rolling bearing in which no seal members are provided at the end openings on both axial sides of the bearing space. This rolling bearing receives oil supplied from outside the bearing directly into the interior of the bearing to lubricate the interior of the bearing. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2018-146040 [Patent Document 2] DE102018125642A1 Summary of the Invention [Problem to be solved by the invention]

[0007] Incidentally, the rolling bearing of Patent Document 1 has a filter portion in the seal member that allows oil to pass through, but the amount of oil that can pass through the filter portion is small. Therefore, when the rolling bearing of Patent Document 1 is used in the high-speed rotation range, there is a risk of oil starvation (starvation) occurring inside the bearing.

[0008] Furthermore, the rolling bearing of Patent Document 2 is not provided with a seal member, and is configured so that oil supplied from outside the bearing is introduced directly into the bearing space. For example, the dmn value (pitch circle diameter dm (mm) of the rolling element × rotation speed n (min -1 When used in a high-speed rotation range where the rpm exceeds 650,000, the oil supplied from outside the bearing is swept away by the rolling elements and cage which move at high speed, preventing oil from flowing from outside the bearing into the inside of the bearing. As a result, the amount of oil passing through the inside of the bearing decreases, and there is a risk of the inside of the bearing becoming abnormally hot.

[0009] The problem to be solved by this invention is to provide a rolling bearing that can prevent insufficient lubrication and abnormal temperature rise inside the bearing during high speed rotation. [Means for solving the problem]

[0010] In order to solve the above problems, the present invention provides a rolling bearing having the following configuration. [Configuration 1] The outer ring and an inner ring disposed radially inside the outer ring; a plurality of rolling elements incorporated in an annular bearing space formed between the outer ring and the inner ring; a cage that holds the plurality of rolling elements, an outer ring fixed seal member shaped like an annular plate that covers one axial end opening of the bearing space, leaving an annular first gap at a radially inner end of the one axial end opening; a ring-shaped inner ring fixed seal member that covers the other axial end opening of the bearing space, leaving an annular second gap at a radially outer end of the other axial end opening, the inner ring stationary seal member is a metal shield plate that has an inclined portion that extends axially inwardly from the radial outer end of the inner ring stationary seal member toward the radial inside, and is positioned so that an imaginary line extending from the axially outer side surface of the inclined portion passes through the position of the radially inner end of the other axial end face of the outer ring.

[0011] With this configuration, the inner ring stationary seal member rotates integrally with the inner ring during bearing rotation, causing oil that contacts the inner ring stationary seal member at the axially outer side of the inner ring stationary seal member to move radially outward due to centrifugal force along the axially outer side surface of the inclined portion of the inner ring stationary seal member. Here, the inclined portion is positioned so that an imaginary line extending from the axially outer side surface of the inclined portion passes through the position of the radially inner end of the axial end face of the outer ring. Therefore, oil that moves radially outward along the inclined portion at the axially outer side of the inner ring stationary seal member flows radially across a position adjacent to the axially outer side of the second gap between the inner ring stationary seal member and the outer ring, creating an ejector effect that creates a negative pressure in the second gap. Meanwhile, because the outer ring stationary seal member does not rotate even when the inner ring rotates, no centrifugal force is generated even when oil comes into contact with the outer ring stationary seal member. As a result, when the bearing is rotating, negative pressure generated in the second gap between the inner ring stationary seal member and the outer ring causes an oil flow toward the second gap inside the bearing, which in turn causes an oil flow to be drawn into the bearing from the first gap between the outer ring stationary seal member and the inner ring, thereby preventing insufficient lubrication inside the bearing during high-speed rotation.

[0012] Furthermore, when the bearing rotates, oil outside the bearing is drawn into the bearing space through the first gap between the outer ring stationary seal member and the inner ring, and then this drawn oil moves through the interior of the bearing and is discharged from the bearing space through the second gap between the inner ring stationary seal member and the outer ring. This creates an overall flow in which the oil inside the bearing is constantly replaced, keeping the inside of the bearing cool and preventing abnormal temperature increases inside the bearing during high-speed rotation.

[0013] [Configuration 2] 2. The rolling bearing according to claim 1, wherein the outer ring stationary seal member is a metallic shield plate.

[0014] By employing this configuration, the first gap can be reliably formed between the outer ring fixed seal member and the inner ring.

[0015] [Configuration 3] an inner end cylindrical portion formed by bending the outer ring fixed seal member inward in the axial direction is formed at the radial inner end of the outer ring fixed seal member, 3. The rolling bearing according to configuration 1 or 2, wherein the outer periphery of the inner ring is formed with a cylindrical surface radially facing the inner end cylindrical portion, and a tapered surface inclined radially outward from the axial inner end of the cylindrical surface toward the axially inner side.

[0016] By adopting this configuration, when the bearing rotates, oil present in the first gap between the outer ring stationary seal member and the inner ring is caused to rotate by coming into contact with the cylindrical surface and tapered surface on the outer circumference of the inner ring, and the centrifugal force generated by this rotation allows it to be smoothly introduced into the interior of the bearing.

[0017] [Configuration 4] The rolling elements are balls, 4. The rolling bearing according to any one of configurations 1 to 3, wherein the cage is an iron plate cage formed by connecting a pair of opposing corrugated annular bodies, each having arc-shaped pocket wall portions that hold the rolling elements and flat plate portions that have axially extending rivet holes formed therein, alternately arranged in the circumferential direction, with rivets inserted into the rivet holes.

[0018] This configuration allows oil to flow smoothly from the first gap through the interior of the bearing to the second gap during rotation, making it possible to particularly effectively prevent abnormal temperature increases inside the bearing. Specifically, by using a steel plate cage, consisting of a pair of corrugated annular bodies with arc-shaped pocket walls and flat sections alternated in the circumferential direction and joined with rivets, as the cage that holds the rolling elements, the cross-sectional area of ​​the portion of the cage (flat sections) between adjacent rolling elements can be kept small. Therefore, when oil is introduced into the bearing from the first gap through the interior of the bearing and moves through the second gap to the second gap, the oil flows smoothly, making it possible to particularly effectively prevent abnormal temperature increases inside the bearing.

[0019] [Configuration 5] 5. The rolling bearing according to any one of configurations 1 to 4, wherein the radial width of the first gap is set to a size of 0.5 mm or more and 1.5 mm or less.

[0020] With this configuration, the radial width of the first gap is 0.5 mm or more, so oil supplied from outside the bearing can be smoothly introduced into the first gap. Also, because the radial width of the first gap is 1.5 mm or less, when oil introduced into the bearing collides with the rolling elements or cage moving at high speed and is scraped away, the scraped away oil can be reliably retained within the bearing space.

[0021] [Configuration 6] 6. The rolling bearing according to any one of configurations 1 to 5, wherein the radial width of the second gap is set to a size of 0.5 mm or more and 1.5 mm or less.

[0022] When this configuration is adopted, the radial width of the second gap is 0.5 mm or more, so that oil inside the bearing can be smoothly discharged from the second gap.

[0023] [Configuration 7] 7. The rolling bearing according to any one of configurations 1 to 6, wherein the inclination angle of the inclined portion relative to the direction perpendicular to the axial direction is set to 10° or more.

[0024] By adopting this configuration, oil moving radially outward along the axially outer side of the inner ring stationary seal member can be reliably brought into contact with the inclined portion, making it possible to effectively apply centrifugal force to the oil.

[0025] The present invention also provides a bearing device using the above-mentioned rolling bearing, which has the following configuration. [Configuration 8] A rolling bearing according to any one of configurations 1 to 7; a housing having an inner periphery into which the outer periphery of the outer ring is fitted; a rotating shaft having an outer periphery into which the inner periphery of the inner ring is fitted; an oil supply device that supplies oil to the rolling bearing. [Effects of the Invention]

[0026] In the rolling bearing of this invention, the inner ring stationary seal member rotates integrally with the inner ring during bearing rotation, causing oil that contacts the inner ring stationary seal member at the axial outside of the inner ring stationary seal member to move radially outward along the axially outer side surface of the inclined portion of the inner ring stationary seal member due to centrifugal force. Here, the inclined portion is positioned so that an imaginary line extending from the axially outer side surface of the inclined portion passes through the position of the radially inner end of the axial end face of the outer ring. Therefore, oil that moves radially outward along the inclined portion at the axial outside of the inner ring stationary seal member flows radially across a position adjacent to the axially outer side of the second gap between the inner ring stationary seal member and the outer ring, creating an ejector effect that creates a negative pressure in the second gap. Meanwhile, because the outer ring stationary seal member does not rotate even when the inner ring rotates, no centrifugal force is generated even when oil comes into contact with the outer ring stationary seal member. As a result, when the bearing is rotating, negative pressure generated in the second gap between the inner ring stationary seal member and the outer ring causes an oil flow toward the second gap inside the bearing, which in turn causes an oil flow to be drawn into the bearing from the first gap between the outer ring stationary seal member and the inner ring, thereby preventing insufficient lubrication inside the bearing during high-speed rotation.

[0027] Furthermore, when the bearing rotates, oil outside the bearing is drawn into the bearing space through the first gap between the outer ring stationary seal member and the inner ring, and then this drawn oil moves through the interior of the bearing and is discharged from the bearing space through the second gap between the inner ring stationary seal member and the outer ring. This creates an overall flow in which the oil inside the bearing is constantly replaced, keeping the inside of the bearing cool and preventing abnormal temperature increases inside the bearing during high-speed rotation. [Brief explanation of the drawings]

[0028] [Figure 1] 1 is a cross-sectional view showing a rolling bearing according to an embodiment of the present invention; [Figure 2] An enlarged view of the oil discharge gap (second gap) and its vicinity between the outer ring and the inner ring stationary seal member in Figure 1. [Figure 3] A schematic diagram showing the oil flow when the rolling bearing in Figure 1 is rotating at high speed. [Figure 4]This figure shows the results of an analysis of the oil movement state at the circumferential position of the rolling element when the rolling bearing in Figure 1 is rotating at high speed. [Figure 5] This figure shows the results of an analysis of the oil movement state at circumferential positions on the flat part of the cage when the rolling bearing in Figure 1 is rotating at high speed. DETAILED DESCRIPTION OF THE INVENTION

[0029] Fig. 1 shows an oil-lubricated rolling bearing (hereinafter simply referred to as "rolling bearing") according to an embodiment of the present invention. This rolling bearing comprises an outer ring 1, an inner ring 2 arranged coaxially radially inward of the outer ring 1, a plurality of rolling elements 4 spaced circumferentially in an annular bearing space 3 formed between the outer ring 1 and the inner ring 2, a cage 5 that maintains the circumferential spacing of the plurality of rolling elements 4, an annular plate-shaped outer ring stationary seal member 6 that covers one axial end opening of the bearing space 3 (the right side in the figure), and an annular plate-shaped inner ring stationary seal member 7 that covers the other axial end opening of the bearing space 3 (the left side in the figure). The bearing bore diameter of this rolling bearing (i.e., the bore diameter of the inner ring 2) is set in the range of 30 mm to 45 mm.

[0030] The axial direction is the direction parallel to the central axis of the outer ring 1 (the central axis of rotation of the bearing), the radial direction is the direction perpendicular to the central axis of the outer ring 1, and the circumferential direction is the direction along the circumference that goes around the central axis of the outer ring 1. Additionally, the axially inner side is the side closer to the rolling elements 4 along the axial direction, and the axially outer side is the side farther from the rolling elements 4 along the axial direction.

[0031] The inner circumference of the outer ring 1 is formed with an outer ring raceway groove 8 with which the rolling elements 4 roll and make contact, a pair of outer ring shoulders 9 located axially outside the outer ring raceway groove 8, and a pair of circumferential grooves 10 located axially outside each of the pair of outer ring shoulders 9.

[0032] The outer ring raceway groove 8 is an arcuate groove with a concave arcuate cross section that conforms to the surface of the rolling elements 4, and extends circumferentially through the axial center of the inner circumference of the outer ring 1. A pair of outer ring shoulders 9 are bank-shaped portions that extend circumferentially on both sides of the outer ring raceway groove 8 in the axial direction. The radial outer end of the outer ring stationary seal member 6 is fitted into and fixed in one of the pair of circumferential grooves 10 (the circumferential groove 10 on the right in the figure). The outer ring 1 has a symmetrical shape with respect to an imaginary axis-perpendicular plane that passes through the axial center of the outer ring 1.

[0033] The outer periphery of the inner ring 2 is formed with an inner ring raceway groove 11 with which the rolling elements 4 roll and make contact, a pair of inner ring shoulders 12 located axially outside the inner ring raceway groove 11, a pair of cylindrical surfaces 13 located axially outside each of the pair of inner ring shoulders 12, and tapered surfaces 14 connecting the inner ring shoulders 12 and the cylindrical surfaces 13.

[0034] The inner ring raceway groove 11 is an arcuate groove with a concave arcuate cross section that conforms to the surface of the rolling elements 4, and extends circumferentially through the axial center of the outer circumference of the inner ring 2. The pair of inner ring shoulders 12 are bank-shaped portions that extend circumferentially on both sides of the inner ring raceway groove 11 in the axial direction. The inner circumference of the inner ring stationary seal member 7 is fitted and fixed to one of the pair of cylindrical surfaces 13 (the left cylindrical surface 13 in the figure). Like the outer ring 1, the inner ring 2 is symmetrical with respect to an imaginary axis-perpendicular plane that passes through the axial center of the inner ring 2.

[0035] The axially outer end of the cylindrical surface 13 is connected to the axial end face of the inner ring 2. The outer diameter of the cylindrical surface 13 is smaller than the outer diameter of the inner ring shoulder 12. The tapered surface 14 extends from the axially inner end of the cylindrical surface 13, sloping radially outward toward the axially inner side (the side closer to the rolling elements 4), and is connected to the axially outer end of the inner ring shoulder 12.

[0036] The rolling elements 4 are sandwiched radially between the outer ring raceway groove 8 and the inner ring raceway groove 11. This sealed rolling bearing is a deep groove ball bearing. That is, the rolling elements 4 are balls, the outer ring raceway groove 8 is a circular arc groove symmetrical about the axial center of the outer ring 1, and the inner ring raceway groove 11 is also a circular arc groove symmetrical about the axial center of the inner ring 2.

[0037] The cage 5 is an iron plate cage formed by a pair of opposing corrugated annular bodies 18, each having arc-shaped pocket wall portions 15 for holding the rolling elements 4 and flat plate portions 17 with rivet holes 16 formed therein, alternately arranged in the circumferential direction, and joined by rivets 19 inserted into the rivet holes 16. The pair of heads of each rivet 19 is formed hemispherically. The axial width of the cage 5 at the position of the flat plate portions 17 (width excluding the rivets 19) is set to be less than ¼ of the diameter of the rolling elements 4.

[0038] The outer ring stationary seal member 6 is a metal shield plate without a rubber seal lip. The outer ring stationary seal member 6 covers the axial end opening of the bearing space 3, leaving an annular oil introduction gap (first gap) 20 at the radially inner end of the end opening. An inner end cylindrical portion 21 is formed at the radially inner end of the outer ring stationary seal member 6 by bending it axially inward (to the left in the figure). The inner end cylindrical portion 21 faces radially opposite the cylindrical surface 13 on the outer circumference of the inner ring 2, forming an oil introduction gap 20 between their opposing surfaces. The oil introduction gap 20 is formed in an annular shape extending continuously around the entire circumference between the radially inner end of the outer ring stationary seal member 6 and the outer circumference of the inner ring 2. The radial width of the oil introduction gap 20 is set to be 0.5 mm or more and 1.5 mm or less. The outer diameter of the inner end cylindrical portion 21 is smaller than the outer diameter of the inner ring shoulder 12.

[0039] The inner ring stationary seal member 7 is also a metal shield plate without a rubber seal lip. The inner ring stationary seal member 7 covers the axial end opening of the bearing space 3, leaving an annular oil discharge gap (second gap) 22 at the radially outer end of the end opening. The oil discharge gap 22 is formed in an annular shape that extends continuously around the entire circumference between the radially outer end of the inner ring stationary seal member 7 and the inner circumference of the outer ring 1.

[0040] The inner ring fixed seal member 7 has a cylindrical fitting portion 23 that is fitted and fixed to the cylindrical surface 13 on the outer periphery of the inner ring 2 with an interference, a raised portion 24 that extends radially outward from the axial inner end of the cylindrical fitting portion 23, and an inclined portion 25 that extends radially outward at an angle from the radial outer end of the raised portion 24.

[0041] The rising portion 24 is formed in the shape of a flat plate perpendicular to the axial direction. The inclined portion 25 is formed in the shape of a conical plate that extends inclined axially inward from the radial outer end of the inner ring fixed seal member 7 toward the radial inside. The fitting cylindrical portion 23, the rising portion 24, and the inclined portion 25 are integrally formed by press-forming a steel plate.

[0042] As shown in Figure 2, the other axial end face 1a of the outer ring 1 (the left side in the figure) is a flat surface perpendicular to the axial direction, and its radially inner end is connected to the inner circumferential surface 1c of the outer ring 1 via a chamfered portion 1b. An oil discharge gap 22 is formed between the inner circumferential surface 1c of the outer ring 1 and the radially outer end of an inclined portion 25 of the inner ring fixed seal member 7. The radial width δ of this oil discharge gap 22 is set to be equal to or greater than 0.5 mm and equal to or less than 1.5 mm.

[0043] The inclination angle θ of inclined portion 25 relative to the direction perpendicular to the axial direction is set to be between 10° and 25° (20° or less in the illustration). The inner ring fixed seal member 7 is positioned so that an imaginary line L extending radially outward from the axially outer side surface (left side in the illustration) of inclined portion 25 passes through the position of the radially inner end of the other axial end face 1a (left side in the illustration) of the outer ring 1. Here, imaginary line L passing through the position of the radially inner end of axial end face 1a of the outer ring 1 means that imaginary line L passes through a region near the radially inner end of axial end face 1a of the outer ring 1 (in the illustration, the boundary position between axial end face 1a of the outer ring 1 and chamfered portion 1b) (specifically, a region within a circle with a radius of 0.5 mm centered on the radially inner end of axial end face 1a of the outer ring 1 in a cross section taken along a plane including the central axis of the outer ring 1).

[0044] As shown in Figure 3, this rolling bearing can be used in a bearing device in which the outer ring 1 is fitted onto the inner periphery of a non-rotating housing 26, and the inner periphery of the inner ring 2 is fitted onto the outer periphery of a rotating shaft 27. In Figure 3, the axial end face of the outer ring 1 on the side of the oil inlet gap 20 abuts against a step on the inner periphery of the housing 26, and the axial end face 1a of the outer ring 1 on the side of the oil discharge gap 22 does not abut against the housing 26 and is exposed.

[0045] During bearing rotation, this bearing device introduces oil supplied from an oil supply device (not shown) into bearing space 3, lubricating the interior of the bearing with that oil. The oil supply device can be a splash lubrication type in which oil is splashed up by the rotation of a gear (not shown) and then splashed onto the bearing, a jet lubrication type in which oil pressurized from an oil pump (not shown) is sprayed from an oil supply nozzle, an air-oil lubrication type in which oil is mixed with compressed air and this compressed air (oil air) is supplied, or a circulating oil supply type in which oil is constantly circulated using an oil pump (not shown).

[0046] As shown in Fig. 3, when this rolling bearing rotates, the inner ring stationary seal member 7 rotates integrally with the inner ring 2, and oil that comes into contact with the inner ring stationary seal member 7 on the axial outside (left side in the figure) of the inner ring stationary seal member 7 moves radially outward due to centrifugal force along the axially outer side surface of the inclined portion 25 of the inner ring stationary seal member 7. Here, as shown in Fig. 2, the inclined portion 25 is positioned so that an imaginary line L extending from the axially outer side surface of the inclined portion 25 passes through the position of the radially inner end of the axial end face 1a of the outer ring 1. Therefore, as shown in Fig. 3, the oil that moves radially outward (upper side in the figure) along the inclined portion 25 on the axial outside (left side in the figure) of the inner ring stationary seal member 7 flows radially across a position adjacent to the axial outside of the oil discharge gap 22 between the inner ring stationary seal member 7 and the outer ring 1, and the ejector effect created by this flow creates a negative pressure in the oil discharge gap 22. On the other hand, because the outer ring stationary seal member 6 does not rotate when the inner ring 2 rotates, no centrifugal force is generated even when oil comes into contact with the outer ring stationary seal member 6. As a result, when the bearing rotates, negative pressure generated in the oil discharge gap 22 between the inner ring stationary seal member 7 and the outer ring 1 causes an oil flow toward the oil discharge gap 22 inside the bearing, and this generates a flow that draws oil into the bearing from the oil introduction gap 20 between the outer ring stationary seal member 6 and the inner ring 2. This prevents insufficient lubrication inside the bearing during high-speed rotation.

[0047] Furthermore, with this rolling bearing, when the bearing rotates, oil outside the bearing is drawn into the bearing space 3 through the oil inlet gap 20 between the outer ring stationary seal member 6 and the inner ring 2, and this drawn oil then moves through the interior of the bearing and is discharged from the bearing space 3 through the oil outlet gap 22 between the inner ring stationary seal member 7 and the outer ring 1. This creates an overall flow in which the oil inside the bearing is constantly replaced, enabling the interior of the bearing to be kept cool. This prevents abnormal temperature increases inside the bearing during high-speed rotation.

[0048] Furthermore, since this rolling bearing uses a metal shield plate as the outer ring stationary seal member 6, the oil introduction gap 20 can be reliably formed between the outer ring stationary seal member 6 and the inner ring 2.

[0049] Furthermore, this rolling bearing employs a configuration in which a cylindrical surface 13 and a tapered surface 14 that slopes radially outward from the axially inner end of cylindrical surface 13 toward the axially inner side are formed on the outer circumference of the inner ring 2, with the inner end cylindrical portion 21 of the outer ring stationary seal member 6 facing cylindrical surface 13. As a result, when the bearing rotates, oil present in the oil introduction gap 20 between the outer ring stationary seal member 6 and the inner ring 2 comes into contact with the cylindrical surface 13 and tapered surface 14 on the outer circumference of the inner ring 2 and is caused to rotate, allowing the centrifugal force generated by this rotation to smoothly introduce oil into the interior of the bearing.

[0050] As shown in FIG. 1 , this rolling bearing employs a steel plate cage as the cage 5 that holds the rolling elements 4. The steel plate cage is made up of a pair of corrugated annular bodies 18, each having arc-shaped pocket walls 15 and flat plate portions 17 alternately arranged in the circumferential direction, joined by rivets 19. This ensures smooth oil flow from the oil inlet gap 20 through the interior of the bearing to the oil discharge gap 22 during bearing rotation, making it possible to particularly effectively prevent abnormal temperature increases inside the bearing. That is, when a steel plate cage is used as the cage 5, the cross-sectional area of ​​the portion of the cage 5 (flat plate portions 17) between circumferentially adjacent rolling elements 4 can be kept small. This means that oil introduced from the oil inlet gap 20 into the bearing interior moves easily between adjacent rolling elements 4 as it passes through the interior of the bearing to the oil discharge gap 22. This ensures smooth oil flow from the oil inlet gap 20 through the interior of the bearing to the oil discharge gap 22 during bearing rotation, making it possible to particularly effectively prevent abnormal temperature increases inside the bearing.

[0051] Furthermore, in this rolling bearing, the radial width of the oil introduction gap 20 is 0.5 mm or more, so oil supplied from outside the bearing can be smoothly introduced into the oil introduction gap 20. Furthermore, the radial width of the oil introduction gap 20 is 1.5 mm or less, so when oil introduced into the bearing collides with the rolling elements 4 or cage 5 moving at high speed and is scraped away, the scraped away oil can be reliably retained within the bearing space 3.

[0052] Furthermore, in this rolling bearing, the radial width δ of the oil discharge gap 22 is 0.5 mm or more, so that the oil inside the bearing can be smoothly discharged from the oil discharge gap 22.

[0053] Furthermore, as shown in Figure 2, in this rolling bearing, the inclination angle θ of the inclined portion 25 relative to the direction perpendicular to the axial direction is set to 10° or more, so that, as shown in Figure 3, oil moving radially outward on the axially outer side (left side in the figure) of the inner ring fixed seal member 7 can be reliably brought into contact with the axially outer side surface of the inclined portion 25, making it possible to effectively apply centrifugal force to the oil.

[0054] Figures 4 and 5 show the results of an analysis of the oil flow inside the rolling bearing of the above embodiment when it is rotated at high speed. In this analysis, the oil movement state was analyzed for a deep groove ball bearing of model number 6207 (outer ring 1 outer diameter: 72 mm, inner ring 2 inner diameter: 35 mm, outer ring 1 and inner ring 2 axial width: 17 mm) when the inner ring 2 was rotated at a speed of 20,000 (rpm) while the outer ring 1 was stationary. Figure 4 shows the oil movement state at the circumferential position of the rolling element 4, and Figure 5 shows the oil movement state at the circumferential position between circumferentially adjacent rolling elements 4 (i.e., the circumferential position of the flat portion 17 of the cage 5).

[0055] From the analysis results shown in Figures 4 and 5, it can be confirmed that oil flows into the inside of the bearing through the oil inlet gap 20 between the outer ring fixed seal member 6 and the inner ring 2, that the oil moves axially inside the bearing through the radial gap between the flat portion 17 of the retainer 5 and the inner ring raceway groove 11, and is discharged from the oil discharge gap 22 between the inner ring fixed seal member 7 and the outer ring 1.

[0056] The embodiments disclosed herein should be considered to be illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0057] 1 outer ring 1a Other end face in the axial direction 2. Inner circle 3 Bearing space 4 rolling elements 5 Cage 6 Outer ring fixed seal member 7 Inner ring fixed seal member 13 Cylindrical Surface 14 Tapered surface 15 Pocket wall 16 rivet holes 17 Flat plate part 18 Corrugated Annular Body 19 rivets 20 Oil inlet gap (first gap) 21 Inner end cylindrical part 22 Oil discharge gap (second gap) 25 Slope 26 Housing 27 Rotation axis L Virtual Line δ Radial width θ Tilt angle

Claims

1. The outer ring (1) and an inner ring (2) disposed radially inside the outer ring (1); a plurality of rolling elements (4) incorporated in an annular bearing space (3) formed between the outer ring (1) and the inner ring (2); A rolling bearing having a cage (5) for holding the plurality of rolling elements (4), an outer ring fixed seal member (6) in the form of an annular plate that covers one axial end opening of the bearing space (3) while leaving an annular first gap (20) at a radially inner end of the one axial end opening; and a circular plate-shaped inner ring fixed seal member (7) that covers the other axial end opening of the bearing space (3) while leaving an annular second gap (22) at the radially outer end of the other axial end opening, The rolling bearing is characterized in that the inner ring fixed seal member (7) has an inclined portion (25) that extends from the radial outer end of the inner ring fixed seal member (7) toward the radial inner side at an inclination in the axial direction, and is a metal shield plate that is arranged so that an imaginary line (L) extending from the axially outer side surface of the inclined portion (25) passes through the position of the radially inner end of the other axial end face (1 a) of the outer ring (1).

2. 2. A rolling bearing according to claim 1, wherein the outer ring stationary seal member (6) is a metallic shield plate.

3. An inner end cylindrical portion (21) is formed at the radially inner end of the outer ring fixed seal member (6) by bending it axially inward, 3. The rolling bearing according to claim 1, wherein the outer periphery of the inner ring (2) is formed with a cylindrical surface (13) that faces the inner end cylindrical portion (21) in the radial direction, and a tapered surface (14) that slopes radially outward from the axial inner end of the cylindrical surface (13) toward the axial inner side.

4. The rolling elements (4) are balls, 3. A rolling bearing according to claim 1 or 2, wherein the retainer (5) is an iron plate retainer comprising a pair of opposing corrugated annular bodies (18) having arc-shaped pocket wall portions (15) for retaining the rolling elements (4) and flat plate portions (17) having axially extending rivet holes (16) formed therein, arranged alternately in the circumferential direction, and joined together by rivets (19) inserted into the rivet holes (16).

5. 3. The rolling bearing according to claim 1, wherein the radial width of the first gap (20) is set to a size of 0.5 mm or more and 1.5 mm or less.

6. 3. The rolling bearing according to claim 1, wherein the radial width (δ) of the second gap (22) is set to a value not less than 0.5 mm and not more than 1.5 mm.

7. 3. The rolling bearing according to claim 1, wherein the inclination angle (θ) of the inclined portion (25) relative to a direction perpendicular to the axial direction is set to 10° or more.

8. A rolling bearing according to claim 1 or 2; a housing (26) having an inner periphery into which the outer periphery of the outer ring (1) is fitted; a rotating shaft (27) having an outer periphery into which the inner periphery of the inner ring (2) is fitted; an oil supply device that supplies oil to the rolling bearing.

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