Rolling bearing and rotating machine

Abstract

One of the pair of sealing components (7, 8) is an outer ring fixed sealing component (7) fixed to the inner circumference of the outer ring (2), and the other is an inner ring fixed sealing component (8) fixed to the outer circumference of the inner ring (3). An oil supply gap (23) is formed between the inner circumference of the outer ring fixed sealing component (7) and the outer circumference of the inner ring (3) to introduce lubricating oil supplied from the outside of the bearing into the bearing space (4). An oil discharge gap (29) is formed between the outer circumference of the inner ring fixed sealing component (8) and the inner circumference of the outer ring (2) to discharge lubricating oil from the bearing space (4).

Description

Technical Field

[0001] This invention relates to rolling bearings and rotating machinery equipped with the rolling bearings. Background Technology

[0002] [Background of the First Invention]

[0003] As bearings supporting rotating shafts in automobiles, industrial machinery, etc., rolling bearings are mostly used (e.g., Patent Documents 1 and 2). The rolling bearings in Patent Documents 1 and 2 have: an outer ring, an inner ring disposed radially inside the outer ring, a plurality of rolling elements installed in an annular bearing space formed between the outer ring and the inner ring, and a pair of sealing members that respectively cover one end opening in the axial direction and the other end opening in the axial direction of the bearing space.

[0004] In the rolling bearing of Patent Document 1, the following structure is adopted: a pair of sealing components are both outer ring fixed sealing components fixed to the inner circumference of the outer ring, and a labyrinth gap is formed between the inner circumference of the outer ring fixed sealing component and the outer circumference of the inner ring. This rolling bearing lubricates the bearing interior by introducing lubricating oil supplied from the outside of the bearing into the bearing space through the labyrinth gap between the inner circumference of the outer ring fixed sealing component and the outer circumference of the inner ring.

[0005] On the other hand, in the rolling bearing of Patent Document 2, the following structure is adopted: a pair of sealing components are both inner ring fixed sealing components fixed to the outer circumference of the inner ring, and a radial clearance is formed between the outer circumference of the inner ring fixed sealing component and the inner circumference of the outer ring. Because the pair of sealing components are inner ring fixed sealing components that rotate integrally with the inner ring, the lubricating oil inside the bearing moves radially outward due to centrifugal force and is discharged to the outside of the bearing through the radial clearance between the outer circumference of the inner ring fixed sealing component and the inner circumference of the outer ring. Therefore, the lubricating oil is less likely to remain inside the bearing, and the stirring resistance of the lubricating oil inside the bearing can be suppressed to a smaller extent.

[0006] [Background of the Second Invention]

[0007] A rolling bearing comprises: an inner part including a first raceway surface, an outer part including a second raceway surface, a plurality of rolling elements disposed between these raceways, and a cage for holding these rolling elements.

[0008] When a rolling bearing rotates at high speed, sufficient lubrication occurs when a certain amount of oil is present at the inlet where the rolling elements and the raceway surface come into contact with the elastic fluid, resulting in sufficient lubrication where the oil film thickness no longer increases. It is known that if the oil supply to the rolling bearing is insufficient during high-speed rotation, it results in starvation, where the oil film thickness between the rolling elements and the raceway surface thins, and the rolling viscous resistance decreases (Non-Patent Literature 1-3).

[0009] When a rolling bearing is rotated at high speed by means of oil lubrication, as in the test examples of Non-Patent Documents 1 and 2, an open bearing without seals, shields, etc. is usually used. The inner part is arranged on the rotating part side of the rotating machinery, the outer part is arranged on the housing side of the rotating machinery, and an oil supply part is provided in the rotating machinery to supply oil to the side of the rolling bearing.

[0010] In the test examples of open bearings disclosed in Non-Patent Documents 1 and 2, the following situation was observed: when the oil supply rate was 70 ml / min and 100 ml / min, sufficient lubrication was maintained up to the highest bearing rotation speed under the test conditions; however, when the oil supply rate was 40 ml / min, insufficient lubrication occurred at the bearing rotation speed, which was lower than the highest bearing rotation speed under the test conditions.

[0011] In oil-air lubrication systems used in machine tool spindles, the oil supply unit can independently and precisely control a small amount of oil. Therefore, by adjusting the oil supply based on the bearing rotation speed, the insufficient lubrication state can be stabilized to the point where the oil film between the rolling elements and the track surface does not break, thus actively reducing frictional torque. Non-Patent Document 3 discloses a method for theoretically estimating the frictional torque when the oil supply is small, as in oil-air lubrication systems.

[0012] Patent Document 1: Japanese Patent Application Publication No. 2013-060957

[0013] Patent Document 2: DE102020112044A1

[0014] Non-Patent Literature 1: Toyama, “Lubrication Analysis of High-Speed ​​Rotating Deep Groove Ball Bearings (Issue 1) – Evaluation of the Influence of Oil Supply Based on Lubrication Visualization –” Proceedings of Tribology Conference Spring 2023, Tokyo, pp. 240-244

[0015] Non-Patent Document 2: Toyama, “Lubrication Analysis of High-Speed ​​Rotating Deep Groove Ball Bearings (2nd Report) - Evaluation of the Influence of Oil Supply Based on Lubrication Visualization -”, Proceedings of Tribology Conference Spring 2023 Tokyo, pp. 245-246

[0016] Non-Patent Document 3: Fujiwara, "Estimation Method for Frictional Torque of Angular Contact Ball Bearings after Oil-Air Lubrication; Lubrication Analysis of High-Speed ​​Rotating Deep Groove Ball Bearings (No. 1) - Evaluation of the Influence of Oil Supply Based on Lubrication Visualization -", NTNTECHNICAL REVIEW No. 82 (2014), pp. 54-60

[0017] [First Invention Project]

[0018] However, in recent years, in the field of electric vehicles such as EVs (pure electric vehicles) and HEVs (hybrid electric vehicles), in order to achieve the miniaturization and lightweighting of electric motors, the high-speed rotation of electric motors is being promoted.

[0019] When the rolling bearing of Patent Document 1 is used for such high-speed rotation, the following problem exists: the lubricating oil introduced from the labyrinth gap between the inner circumference of the outer ring fixed seal and the outer circumference of the inner ring is prone to remain inside the bearing, and the rotational resistance of the bearing increases due to the stirring resistance of the lubricating oil remaining inside the bearing.

[0020] Therefore, in order to reduce the stirring resistance of the lubricating oil inside the bearing, the rolling bearing of Patent Document 2 can be considered. However, when the rolling bearing of Patent Document 2 is used for high-speed rotation, the lubricating oil inside the bearing is discharged to the outside of the bearing due to centrifugal force from the radial gap between the outer circumference of the inner ring fixing seal and the inner circumference of the outer ring. This may lead to insufficient lubricating oil inside the bearing, resulting in problems such as abnormal heating, peeling damage, and burning.

[0021] The problem to be solved by the first invention is to provide a rolling bearing that is not prone to insufficient lubricating oil inside the bearing when rotating at high speed and can suppress the stirring resistance of the lubricating oil inside the bearing to a small extent.

[0022] [Second Invention Topic]

[0023] In today's energy-efficient environment, rolling bearings are required to have low torque characteristics. Therefore, the oil supply is limited to a small amount to suppress churning resistance. When a small amount of oil is supplied to the sides of an open bearing, this small amount mixes with the surrounding air and enters the bearing interior. As a result, an air curtain is generated on both sides of the open bearing during high-speed rotation. This air curtain is caused by the high-speed rotating cage and the multiple rolling elements stirring the lubricating fluid, causing the oil and other lubricating fluids to swirl circumferentially and diffuse laterally. If the air curtain is strong, the oil supplied to the sides of the open bearing cannot penetrate the annular space of the rolling bearing, reducing the amount of oil contributing to the lubrication and cooling of the rolling elements, thus leading to insufficient lubrication.

[0024] However, in applications where the failure resistance of rolling bearings is crucial, high-speed rotation under adequate lubrication is sometimes required. In rotating machinery equipped with an oil supply unit capable of precisely controlling a small amount of oil, similar to oil-air lubrication, adequate lubrication can be maintained by increasing the oil supply from the oil supply unit, taking into account the increase in bearing rotational speed and the influence of the air curtain. However, there are situations where such a controlled oil supply unit cannot be used. For example, in an electric axle assembly (e-Axle) that integrates an electric motor, gear reducer, and inverter for vehicle drive, the rotational speeds of the motor shaft, the input shaft of the reducer, and the second-stage and subsequent drive shafts of the reducer differ significantly. Therefore, the desired oil supply differs for the rolling bearings supporting high-speed shafts such as the input shaft and for the rolling bearings supporting the second-stage and subsequent drive shafts. Setting up a dedicated controlled oil supply unit for the oil lubrication of rolling bearings supporting high-speed shafts would result in a larger and more complex unit, which is unacceptable. In such an operating environment, it is impossible to increase the rotational speed of a bearing that suffers from insufficient lubrication (i.e., the upper limit of the rotational speed of a bearing that maintains sufficient lubrication) to meet the requirements of high-speed rotation.

[0025] In view of the above background, the problem to be solved by the second invention is to increase the rotational speed of bearings that suffer from insufficient lubrication without making the electric axle assembly larger and more complex. Summary of the Invention

[0026] To solve the above-mentioned problems, the first invention provides a rolling bearing with the following structure.

[0027] [Structure 1]

[0028] A rolling bearing having:

[0029] Outer ring;

[0030] The inner ring is located radially inside the outer ring described above;

[0031] Multiple rolling elements are fitted into an annular bearing space formed between the outer ring and the inner ring; and

[0032] A pair of sealing components respectively cover one axial end opening and the other axial end opening of the aforementioned bearing space.

[0033] The aforementioned rolling bearing is characterized in that,

[0034] One of the aforementioned pair of sealing components is an outer ring fixing sealing component fixed to the inner circumference of the outer ring, and the other is an inner ring fixing sealing component fixed to the outer circumference of the inner ring.

[0035] An oil drain gap is formed between the outer periphery of the inner ring fixed sealing component and the inner periphery of the outer ring to drain lubricating oil from the bearing space.

[0036] An oil supply gap is formed between the inner circumference of the outer ring fixed sealing component and the outer circumference of the inner ring, allowing lubricating oil supplied from outside the bearing to enter the bearing space.

[0037] With this structure, the inner ring fixing seal rotates integrally with the inner ring. Therefore, the lubricating oil inside the bearing moves radially outward due to centrifugal force and is discharged to the outside of the bearing through the oil drain gap between the outer circumference of the inner ring fixing seal and the inner circumference of the outer ring. Consequently, the lubricating oil is less likely to remain inside the bearing, thus minimizing the stirring resistance of the lubricating oil inside the bearing.

[0038] Furthermore, even when the inner ring rotates, the outer ring fixing seal does not rotate. Therefore, as the lubricating oil inside the bearing is discharged through the oil drain gap due to centrifugal force, lubricating oil supplied from outside the bearing is drawn into the bearing through the oil supply gap between the inner circumference of the outer ring fixing seal and the outer circumference of the inner ring. Thus, even at high speeds, the lubricating oil inside the bearing is less likely to be insufficient, ensuring stable lubrication of the bearing interior.

[0039] Furthermore, the lubricating oil inside the bearing is discharged to the outside of the bearing through the oil drain gap between the outer circumference of the inner ring fixing seal and the inner circumference of the outer ring, while lubricating oil supplied from the outside of the bearing is drawn into the bearing through the oil supply gap between the inner circumference of the outer ring fixing seal and the outer circumference of the inner ring. Therefore, the lubricating oil inside the bearing is continuously replaced, and heat exchange within the bearing is smooth. This effectively suppresses temperature rise during high-speed rotation.

[0040] [Structure 2]

[0041] In the rolling bearing described in Structure 1,

[0042] The aforementioned outer ring fixing sealing component has a rubber sealing lip, which has a plurality of protrusions spaced apart in the circumferential direction, which slide in contact with the outer periphery of the aforementioned inner ring via an oil film.

[0043] The aforementioned oil supply gap is formed between the aforementioned protrusions that are adjacent in the circumferential direction.

[0044] With this structure, since the oil supply gap is formed between adjacent convex parts of the sealing lip in the circumferential direction, the gap size can be managed with high precision by adjusting the height of the convex parts of the sealing lip. Therefore, the gap size of the oil supply gap can be set to be small, effectively preventing foreign objects from entering the bearing from the outside through the oil supply gap.

[0045] [Structure 3]

[0046] In the rolling bearing described in Structure 2,

[0047] A cylindrical sealing sliding contact surface is formed on the outer periphery of the inner ring. This sealing sliding contact surface extends axially from the part of the sealing lip that makes sliding contact and connects to the axial end face of the inner ring.

[0048] With this structure, the sealing sliding contact surface of the outer circumference of the inner ring is cylindrical, extending axially from the sliding contact area of ​​the sealing lip and connecting to the axial end face of the inner ring. Therefore, compared to the case where the sealing lip slides in contact with the inner surface of the groove, the oil supply gap between the sealing lip and the inner ring is more exposed outside the bearing. Thus, lubricating oil supplied from outside the bearing can be smoothly introduced into the oil supply gap.

[0049] [Structure 4]

[0050] In the rolling bearing described in structure 3,

[0051] A cylindrical sealing and fixing surface is formed on the outer periphery of the inner ring, which is used for the radial inner end of the inner ring fixing sealing component to be fitted and fixed.

[0052] By making the sealing fixing surface and the sealing sliding contact surface symmetrical with the same outer diameter, the shape of the inner ring is made symmetrical with respect to the right-angled plane of the axis.

[0053] If this structure is adopted, the sealing fixed surface and the sealing sliding contact surface can be machined in the same process when manufacturing the inner ring, so the cost is low. In addition, when assembling the rolling bearing, there is no need to distinguish the inside and outside orientation of the inner ring, so the workability is excellent.

[0054] [Structure 5]

[0055] In any of the rolling bearings described in structures 1 to 4,

[0056] A metal shield that does not contact the inner circumference of the outer ring is used as the inner ring fixing and sealing component.

[0057] If this structure is adopted, the inner ring fixed sealing component will not be in contact with the inner circumference of the outer ring, so the rotational resistance of the bearing can be suppressed to a smaller extent.

[0058] [Structure 6]

[0059] In any of the rolling bearings described in structures 1 to 5,

[0060] The aforementioned inner ring fixing sealing component has:

[0061] The fitting cylindrical portion fits into the outer periphery of the aforementioned inner ring;

[0062] The annular plate portion rises radially outward from the aforementioned fitted cylindrical portion; and

[0063] The edge bend is formed by bending the radially outer end of the aforementioned annular plate towards the axially inner side.

[0064] With this structure, the inner ring retaining seal has an edge bend formed by bending the radially outer end of the annular plate towards the axially inner side. Therefore, when lubricating oil drawn into the bearing from the oil supply gap between the inner circumference of the outer ring retaining seal and the outer circumference of the inner ring moves radially outward due to centrifugal force, a portion of this lubricating oil can be caught by the edge bend of the inner ring retaining seal before reaching the oil discharge gap between the outer circumference of the inner ring retaining seal and the inner circumference of the outer ring, thus retaining it inside the bearing. Therefore, it is possible to prevent excessive discharge of lubricating oil drawn into the bearing from the oil supply gap through the oil discharge gap.

[0065] [Structure 7]

[0066] In the rolling bearing described in Structure 6,

[0067] A circumferential groove is formed on the inner circumference of the outer ring, and the circumferential groove extends circumferentially at a position corresponding to the inner ring fixing sealing component.

[0068] At least a portion of the curved edge of the inner ring fixing sealing member is received in the circumferential groove.

[0069] With this structure, at least a portion of the curved edge of the inner ring retaining seal is accommodated in a circumferential groove formed on the inner circumference of the outer ring. Therefore, the curved edge can efficiently catch the lubricating oil inside the bearing that moves along the inner circumference of the outer ring towards the inner ring retaining seal. This effectively prevents excessive discharge of lubricating oil from the bearing through the oil drain gap.

[0070] [Structure 8]

[0071] In the rolling bearing described in structure 7,

[0072] A sealing groove is formed on the inner circumference of the outer ring, and the sealing groove is used for the radial outer end of the outer ring to be fitted and fixed.

[0073] By making the cross-sectional shape of the sealing groove and the cross-sectional shape of the circumferential groove symmetrical, the shape of the outer ring is made symmetrical with respect to the right-angled plane of the axis.

[0074] If this structure is adopted, the sealing groove and the circumferential groove can be machined in the same process when manufacturing the outer ring, so the cost is low. In addition, when assembling the rolling bearing, there is no need to distinguish the inside and outside direction of the outer ring, so the workability is excellent.

[0075] [Structure 9]

[0076] In any of the rolling bearings described in structures 1 to 8,

[0077] The bearing space mentioned above is sealed with grease.

[0078] If this structure is adopted, lubrication inside the bearing can be ensured during the initial use of the bearing until lubricating oil is supplied from the outside of the bearing.

[0079] In addition, to solve the above-mentioned problems, the second invention provides a rolling bearing with the following structure.

[0080] [Structure 10]

[0081] A rolling bearing, comprising:

[0082] The inner component has a first track surface;

[0083] The outer component has a second track surface;

[0084] Multiple rolling elements are disposed between the first track surface and the second track surface; and

[0085] The cage holds the aforementioned rolling elements.

[0086] The aforementioned rolling bearing is characterized in that,

[0087] The aforementioned rolling bearings also possess:

[0088] The protective member protrudes from the inner diameter surface of the outer component toward the outer diameter surface of the inner component at a position axially away from the rolling elements and the cage; and

[0089] The oil slinger ring protrudes from the outer diameter surface of the inner component toward the inner diameter surface of the outer component at a position away from the rolling elements and the cage on the opposite side of the axial direction.

[0090] The aforementioned protective element and the aforementioned inner component form the first oil passage.

[0091] The oil slinger ring and the outer component form a second oil inlet.

[0092] With this structure, when the rolling bearing with the inner component rotates, the lubricating fluid, such as oil, stirred by the rolling elements and cage and directed towards the axial side is received by the shielding member. This reduces the influence of the air curtain on the axial side surface of the rolling bearing, making it easier for oil supplied to the axial side of the rolling bearing to reach the first oil port between the shielding member and the inner component. On the other hand, on the other side of the rolling bearing, the oil lubricating and cooling the rolling elements can be centrifugally applied by the oil slinger ring, promoting oil discharge from the second oil port between the outer component and the oil slinger ring. This suppresses the back pressure of the second oil port relative to the first oil port, making it easier to draw oil in from the first oil port. By reducing the influence of the air curtain on the axial side of the rolling bearing and promoting oil discharge on the other side of the rolling bearing, a centrifugal pump function can be achieved. This prevents backflow of oil from the first oil port, draws oil drawn from the first oil port towards the second oil port, and discharges the oil lubricating and cooling the rolling elements from the second oil port. Increasing the bearing rotation speed enhances this centrifugal pump function. As long as the rolling bearing has protective components and an oil slinger ring for effectively functioning as a centrifugal pump at high speeds, the rotational speed of a bearing that is lacking lubrication can be increased by the rolling bearing itself, without the need for large-scale and complex electric axle assemblies.

[0093] [Structure 11]

[0094] In the rolling bearing described in structure 10,

[0095] The aforementioned cage has an annular portion extending circumferentially on the opposite side of the axial direction relative to the aforementioned plurality of rolling elements.

[0096] The aforementioned oil-slinging ring has a side plate portion that is axially spaced apart from the side surface on the other side of the aforementioned annular portion.

[0097] If this structure is adopted, oil can flow between the annular part of the cage and the side plate part of the oil throwing ring, so as to apply centrifugal force to the oil from both parts in a way that prevents the oil from escaping between them and deliver it to the second oil inlet.

[0098] [Structure 12]

[0099] In the rolling bearing described in structure 11,

[0100] The aforementioned oil slinger ring has a cylindrical plate portion, which is fitted into the aforementioned inner component in a manner that is radially spaced apart from the aforementioned annular portion.

[0101] The aforementioned side plate portion protrudes radially outward from the opposite axial side of the aforementioned cylindrical plate portion.

[0102] The radial distance between the aforementioned cylindrical plate portion and the aforementioned annular portion is set to be smaller than the axial distance between the side surface of the annular portion on the other side of the axial direction and the aforementioned side plate portion.

[0103] If this structure is adopted, oil will not easily pass through the annular part of the cage and the cylindrical part of the oil slinger. Therefore, when the rolling bearing rotates at high speed, the oil tends to become thinner between the inner circumference of the cage and the inner side parts, which can easily supply oil to the rolling elements.

[0104] [Structure 13]

[0105] In the rolling bearing described in structure 11 or 12,

[0106] The radial distance between the outer periphery of the aforementioned side plate portion and the aforementioned outer component is set to be greater than the axial distance between the side surface on the other side of the aforementioned annular portion and the aforementioned side plate portion.

[0107] If this structure is adopted, the oil passing through the annular part of the cage and the side plate part of the oil slinger ring can be easily discharged from the second oil port.

[0108] [Structure 14]

[0109] In the rolling bearing described in structure 13,

[0110] The aforementioned outer component has:

[0111] The shoulder portion is radially spaced from the aforementioned annular portion; and

[0112] The cutout portion, located radially opposite to the aforementioned side plate portion, is larger in diameter than the aforementioned shoulder portion.

[0113] The outer diameter of the aforementioned side plate is set to be smaller than that of the aforementioned shoulder.

[0114] If this structure is adopted, the diameter of the side plate of the oil slinger ring can be prevented from becoming smaller by radially expanding the second oil passage through the cut portion of the outer component, and the oil that has passed between the outer component and the outer periphery of the cage can easily flow towards the second oil passage.

[0115] [Structure 15]

[0116] In any of the rolling bearings described in structures 10-14,

[0117] The inner diameter of the aforementioned protective element is set to be smaller than or equal to the inner diameter of the aforementioned retainer.

[0118] If this structure is adopted, the entire cage and most of the multiple rolling elements are covered from the axial side by the shield, so that most of the oil that is stirred by the cage and rolling elements toward the axial side can be received by the shield to prevent it from flowing back to the first oil port.

[0119] [Structure 16]

[0120] In any of the rolling bearings described in structures 10 to 15,

[0121] The aforementioned retainer is positioned further axially away from the aforementioned shield than the aforementioned rolling element.

[0122] If this structure is adopted, the space between the shield and the rolling element is set wider, so that the oil can diffuse in the space between the two and easily reach the rolling element.

[0123] [Structure 17]

[0124] In any of the rolling bearings described in structures 10 to 16,

[0125] The above-mentioned protective components have:

[0126] The front panel, which is closest to the inner component among the aforementioned protective members; and

[0127] The inner diameter side tapered plate extends from the axial side of the aforementioned front end plate in a direction inclined radially outward.

[0128] If this structure is adopted, the oil supplied to the axial side relative to the rolling bearing can easily enter the first oil port, and the oil received by the protected component can easily reach the rolling element.

[0129] [Structure 18]

[0130] In any of the rolling bearings described in structures 10 to 17,

[0131] The aforementioned retainer is made of a resin component having an annular portion extending in a circumferential direction and multiple pairs of claw portions extending axially from the annular portion in a manner that forms spaces opening radially inward, radially outward, and axially to one side.

[0132] The aforementioned rolling element is composed of balls disposed in the aforementioned space.

[0133] The claw portions located between the aforementioned rolling elements that are adjacent in the circumferential direction are recessed to the opposite side in the axial direction.

[0134] Let a be the minimum axial thickness from the concave end face of the claw portion located on the opposite axial side to the side surface of the cage on the opposite axial side.

[0135] Let b be the axial thickness from the bottom of the bag located on the opposite side of the axial direction in the aforementioned space to the side surface on the opposite side of the axial direction of the aforementioned retainer.

[0136] When the minimum distance between the imaginary plane passing through the centers of the aforementioned rolling elements and the aforementioned concave end face is defined as c...

[0137] The condition is that a > b and c > 0.

[0138] If this structure is adopted, the deformation of the cage caused by centrifugal force during high-speed rotation can be suppressed, thus enabling the rolling bearing to be a ball bearing suitable for high-speed rotation applications.

[0139] [Structure 19]

[0140] A rotating machine, wherein:

[0141] Rolling bearings involved in any of structures 10 to 18;

[0142] The rotating part is supported by the aforementioned rolling bearing; and

[0143] The oil supply section supplies oil to the axial side relative to the aforementioned rolling bearing.

[0144] If this structure is adopted, oil can be drawn in from the first oil port when the rolling bearing is rotating at high speed. Therefore, even without an oil supply section that can control the oil supply with high precision, the rotation speed of the bearing that is lacking lubrication can still be increased, and the rotating part can be operated at high speed.

[0145] Because the inner ring fixing seal component rotates integrally with the inner ring in the rolling bearing of the first invention, the lubricating oil inside the bearing moves radially outward due to centrifugal force and is discharged to the outside of the bearing through the oil discharge gap between the outer circumference of the inner ring fixing seal component and the inner circumference of the outer ring. Therefore, the lubricating oil is less likely to remain inside the bearing, and the stirring resistance of the lubricating oil inside the bearing can be suppressed to a smaller extent.

[0146] Furthermore, even when the inner ring rotates, the outer ring fixing seal does not rotate. Therefore, as the lubricating oil inside the bearing is discharged through the oil drain gap due to centrifugal force, lubricating oil supplied from outside the bearing is drawn into the bearing through the oil supply gap between the inner circumference of the outer ring fixing seal and the outer circumference of the inner ring. Thus, even at high speeds, the lubricating oil inside the bearing is less likely to be insufficient, ensuring stable lubrication of the bearing interior.

[0147] Furthermore, the lubricating oil inside the bearing is discharged to the outside of the bearing through the oil drain gap between the outer circumference of the inner ring fixing seal and the inner circumference of the outer ring, while lubricating oil supplied from the outside of the bearing is drawn into the bearing through the oil supply gap between the inner circumference of the outer ring fixing seal and the outer circumference of the inner ring. Therefore, the lubricating oil inside the bearing is continuously replaced, and heat exchange within the bearing is smooth. This effectively suppresses temperature rise during high-speed rotation.

[0148] The second invention can increase the rotational speed of bearings that suffer from insufficient lubrication without requiring the large size and complexity of electric axle assemblies, etc. Attached Figure Description

[0149] Figure 1 This is a cross-sectional view showing the rolling bearing involved in an embodiment of the first invention.

[0150] Figure 2 yes Figure 1 An enlarged cross-sectional view of the area near the outer ring fixed sealing component.

[0151] Figure 3 It is along Figure 2 A cross-sectional view along line III-III.

[0152] Figure 4 yes Figure 1 An enlarged sectional view of the area near the inner ring fixed sealing component.

[0153] Figure 5 It means Figure 4 The figure shows a deformation example of the edge bend of the inner ring fixed sealing component.

[0154] Figure 6 It means Figure 4 A diagram showing another variation of the edge bend of the inner ring fixing seal component.

[0155] Figure 7 It means Figure 4 The figure shows another variation of the edge bend of the inner ring fixed sealing component.

[0156] Figure 8 It means Figure 4 The figure shows another variation of the edge bend of the inner ring fixed sealing component.

[0157] Figure 9 It means Figure 4 The figure shows another variation of the edge bend of the inner ring fixed sealing component.

[0158] Figure 10 It means Figure 4 The figure shows another variation of the edge bend of the inner ring fixed sealing component.

[0159] Figure 11 It is along Figure 1 A cross-sectional view along line XI-XI.

[0160] Figure 12 It means to Figure 1 The diagram shows the state in which the rolling bearing is assembled in the housing and supports the rotating shaft.

[0161] Figure 13 This is a longitudinal sectional front view showing the main parts of the rolling bearing and the rotating machinery equipped with the rolling bearing according to an embodiment of the second invention.

[0162] Figure 14 It is extraction Figure 13 The cage and the left view shown.

[0163] Figure 15 yes Figure 14 A cross-sectional view of the XV-XV line. Detailed Implementation

[0164] Figure 1 The diagram illustrates a rolling bearing 1 according to an embodiment of the first invention. This rolling bearing 1 includes: an outer ring 2; an inner ring 3 coaxially arranged radially inside the outer ring 2; a plurality of rolling elements 5 spaced circumferentially within an annular bearing space 4 formed between the outer ring 2 and the inner ring 3; a cage 6 maintaining the circumferential spacing of the plurality of rolling elements 5; and a pair of sealing members 7 and 8, respectively covering one axial end opening and the other axial end opening of the bearing space 4. One of the sealing members 7 and 8 is an outer ring fixing sealing member 7 fixed to the inner circumference of the outer ring 2, and the other is an inner ring fixing sealing member 8 fixed to the outer circumference of the inner ring 3. Grease for initial lubrication is sealed into the bearing space 4.

[0165] The inner circumference of the outer ring 2 includes: an outer ring track groove 9 for rolling contact of the rolling element 5; a pair of outer ring shoulders 10 located axially outside the outer ring track groove 9; a sealing and fixing groove 11 located axially outside one of the pair of outer ring shoulders 10 (the left outer ring shoulder 10 in the figure); and a circumferential groove 12 located axially outside the other of the pair of outer ring shoulders 10 (the right outer ring shoulder 10 in the figure). The outer ring track groove 9 is an arcuate groove with a concave arcuate cross-section along the surface of the rolling element 5, extending circumferentially at the axial center of the inner circumference of the outer ring 2. The pair of outer ring shoulders 10 are embankment-like portions extending circumferentially on both sides of the outer ring track groove 9, axially sandwiched. The radially outer end of the outer ring fixing and sealing member 7 is fitted and fixed into the sealing and fixing groove 11.

[0166] The outer periphery of the inner ring 3 is formed with: an inner ring track groove 13 for rolling contact of the rolling element 5, a pair of inner ring shoulders 14 located axially outside the inner ring track groove 13, and a sealing sliding contact surface 15 located axially outside one of the pair of inner ring shoulders 14 (the left inner ring shoulder 14 in the figure) (see reference). Figure 2 The inner ring 3 has a sealing and fixing surface 16 located axially outside the other inner ring shoulder 14 (the right inner ring shoulder 14 in the figure). The inner ring track groove 13 is an arcuate groove with a concave arcuate cross-section along the surface of the rolling element 5, extending circumferentially at the axial center of the outer periphery of the inner ring 3. The pair of inner ring shoulders 14 are embankment-like portions extending circumferentially on both sides of the inner ring track groove 13, axially sandwiching them. The radially inner end of the inner ring fixing sealing member 8 is fitted and fixed to the sealing and fixing surface 16.

[0167] The rolling element 5 is radially clamped between the outer ring raceway 9 and the inner ring raceway 13. This rolling bearing 1 is a deep groove ball bearing. That is, the outer ring raceway 9 is a circular arc groove symmetrical with respect to the axial center of the outer ring 2, and the inner ring raceway 13 is also a circular arc groove symmetrical with respect to the axial center of the inner ring 3.

[0168] like Figure 2 As shown, the outer ring fixing sealing component 7 consists of a circular plate-shaped metal core 17 and rubber 18 vulcanized and bonded to the metal core 17. The metal core 17 is formed, for example, by stamping a steel plate such as cold-rolled steel plate or stainless steel plate. The rubber 18 has: an outer peripheral rubber portion 19 extending radially outward from the radially outer end of the metal core 17, an outer surface rubber portion 20 covering the entire side surface of the axially outer side of the metal core 17, and a sealing lip 21 extending radially inward from the radially inner end of the metal core 17.

[0169] The outer circumferential rubber portion 19 engages with the sealing groove 11 on the inner circumference of the outer ring 2. The sealing lip 21 slides in contact with the sealing sliding contact surface 15 on the outer circumference of the inner ring 3. The sealing sliding contact surface 15 is a cylindrical surface that extends axially with a certain outer diameter from the portion where the sealing lip 21 makes sliding contact and connects to the axial end face 22 of the inner ring 3. An oil supply gap 23 is formed between the inner circumference of the sealing lip 21 and the sealing sliding contact surface 15 to guide lubricating oil supplied from outside the bearing into the bearing space 4.

[0170] like Figure 3 As shown, a plurality of protrusions 24 spaced apart circumferentially are formed on the inner circumference of the sealing lip 21, and an inner circumferential surface 25 connecting adjacent protrusions 24 circumferentially. The protrusions 24 are arranged at equal intervals throughout the entire circumference of the inner circumference of the sealing lip 21. The height of each protrusion 24 (the distance from the inner circumferential surface 25 to the sealing sliding contact surface 15 when the tip of the protrusion 24 is in contact with the sealing sliding contact surface 15) is set to 0.1 mm or less. Each protrusion 24 is formed to extend in a direction intersecting the circumferential direction (e.g., a direction perpendicular to the circumferential direction (orthogonal to the plane of the paper in the figure)). The oil supply gap 23 is the gap formed between adjacent protrusions 24 circumferentially.

[0171] Each protrusion 24 is formed with a convex arc shape in cross-section along the circumferential direction, and slides in contact with the sealing sliding contact surface 15 via an oil film based on the wedge-shaped film effect. That is, when the sealing sliding contact surface 15 of the outer periphery of the inner ring 3 moves circumferentially relative to each protrusion 24, the lubricating oil present between adjacent protrusions 24 along the circumferential direction is introduced along the surface of each protrusion 24 into the space between the protrusion 24 and the sealing sliding contact surface 15. At this time, through the wedge-shaped film effect, the lubrication state between each protrusion 24 and the sealing sliding contact surface 15 becomes a fluid lubrication state, which can suppress the sliding resistance (sealing torque) of the sealing lip 21 to a low level.

[0172] like Figure 4 As shown, the inner ring fixing seal member 8 is a metal shield formed by stamping a metal plate (e.g., steel plate), and is configured to not contact the inner circumference of the outer ring 2. The inner ring fixing seal member 8 has: a fitting cylinder portion 26 that fits into the outer circumference of the inner ring 3, an annular plate portion 27 that stands out radially outward from the fitting cylinder portion 26, and an edge bend portion 28 formed by bending the annular plate portion 27 radially outward towards the axially inward (left side in the figure).

[0173] The fitting cylindrical portion 26 is fixed by interlocking with the sealing fixing surface 16 on the outer periphery of the inner ring 3. The sealing fixing surface 16 is a cylindrical surface that extends axially along a certain outer diameter and connects to the axial end face 22 of the inner ring 3. The sealing fixing surface 16 and the sealing sliding contact surface 15 (see reference) Figure 2 ) are formed into symmetrical shapes with the same outer diameter, thus, as Figure 1 As shown, the inner ring 3 has a shape that is symmetrical with respect to an imaginary axial right-angled plane passing through the axial center of the inner ring 3.

[0174] The circumferential groove 12 of the inner circumference of the outer ring 2 extends circumferentially at a position corresponding to the inner ring fixed sealing member 8, and houses at least a portion (all of it in the figure) of the edge bend 28. The edge bend 28 is a cylindrical portion extending radially outward from the outer end of the annular plate portion 27 towards the axially inward side, and its inner diameter is larger than the inner diameter of the outer ring shoulder portion 10. An oil drain gap 29 is formed between the outer circumference of the edge bend 28 and the inner circumference of the outer ring 2 to drain lubricating oil from the bearing space 4. The oil drain gap 29 is an annular micro-gap (see reference). Figure 11 ).

[0175] The cross-sectional shape of the circumferential groove 12 is similar to that of the sealing and fixing groove 11 (see reference). Figure 3 The cross-sectional shape of ) is symmetrical, therefore, as Figure 1 As shown, the outer ring 2 has a shape that is symmetrical with respect to an imaginary right-angled plane passing through the axial center of the outer ring 2.

[0176] like Figure 12 As shown, the rolling bearing 1 is used to support the rotating shaft 34 so that its inner ring can rotate while it is mounted in a fixed housing 33. The rotating shaft 34 is, for example, the rotating shaft of an electric vehicle that receives the rotation of an electric motor, or the rotating shaft of a hybrid electric vehicle that uses an electric motor as an auxiliary driving force for the engine. The housing 33 is provided with a lubricating oil supply passage 35 that supplies lubricating oil to the rolling bearing 1 from one axial side.

[0177] In the rolling bearing 1, such as Figure 1As shown, since the inner ring fixing seal component 8 rotates integrally with the inner ring 3, the lubricating oil inside the bearing moves radially outward due to centrifugal force and is discharged to the outside of the bearing through the oil discharge gap 29 between the outer circumference of the inner ring fixing seal component 8 and the inner circumference of the outer ring 2. Therefore, the lubricating oil is less likely to remain inside the bearing, and the stirring resistance of the lubricating oil inside the bearing can be suppressed to a smaller extent.

[0178] Furthermore, even if the inner ring 3 rotates, the outer ring fixing seal 7 does not rotate. Therefore, as the lubricating oil inside the bearing is discharged from the oil discharge gap 29 due to centrifugal force, the lubricating oil supplied from the outside of the bearing is drawn into the bearing from the oil supply gap 23 between the inner circumference of the outer ring fixing seal 7 and the outer circumference of the inner ring 3. Thus, during high-speed rotation, the lubricating oil inside the bearing is less likely to be insufficient, and the bearing can be stably lubricated.

[0179] Furthermore, the lubricating oil inside the bearing is discharged to the outside of the bearing through the oil discharge gap 29 between the outer circumference of the inner ring fixing seal 8 and the inner circumference of the outer ring 2, while lubricating oil supplied from the outside of the bearing is drawn into the bearing through the oil supply gap 23 between the inner circumference of the outer ring fixing seal 7 and the outer circumference of the inner ring 3. Therefore, the lubricating oil inside the bearing is continuously replaced, and the heat exchange inside the bearing is smooth. Thus, the temperature rise during high-speed rotation can be effectively suppressed.

[0180] In addition, in this rolling bearing 1, such as Figure 3 As shown, the oil supply gap 23 is formed between adjacent protrusions 24 in the circumferential direction of the sealing lip 21. Therefore, by adjusting the height of the protrusions 24 of the sealing lip 21, the gap size of the oil supply gap 23 can be managed with high precision. Thus, the gap size of the oil supply gap 23 can be set to be small, which can effectively prevent foreign objects from entering the bearing from the outside through the oil supply gap 23.

[0181] In addition, in this rolling bearing 1, such as Figure 2 As shown, the sealing sliding contact surface 15 on the outer periphery of the inner ring 3 is cylindrical, extending axially from the portion where the sealing lip 21 makes sliding contact and connecting to the axial end face 22 of the inner ring 3. Therefore, compared to the case where the sealing lip 21 makes sliding contact with the inner surface of the groove, the oil supply gap 23 between the sealing lip 21 and the inner ring 3 is exposed more extensively outside the bearing. Thus, lubricating oil supplied from outside the bearing can be smoothly introduced into the oil supply gap 23.

[0182] In addition, in this rolling bearing 1, such as Figure 4 As shown, since the inner ring fixing sealing member 8 has an edge bend 28 formed by bending the radially outer end of the annular plate portion 27 towards the axially inner side, therefore, as Figure 1As shown, when the lubricating oil drawn into the bearing from the oil supply gap 23 between the inner circumference of the outer ring fixed sealing component 7 and the outer circumference of the inner ring 3 moves radially outward due to centrifugal force, as... Figure 4 As shown, a portion of the lubricating oil can be caught by the curved edge 28 of the inner ring retaining seal 8 before reaching the oil drain gap 29 between the outer circumference of the inner ring retaining seal 8 and the inner circumference of the outer ring 2, thus retaining it inside the bearing. Therefore, it is possible to prevent oil from... Figure 1 The lubricating oil drawn into the bearing through the oil supply gap 23 is excessively discharged through the oil discharge gap 29.

[0183] In addition, in this rolling bearing 1, such as Figure 4 As shown, since at least a portion of the edge bend 28 of the inner ring retaining seal 8 is accommodated in the circumferential groove 12 formed on the inner circumference of the outer ring 2, the edge bend 28 can efficiently catch the lubricating oil inside the bearing that moves along the inner circumference of the outer ring shoulder 10 toward the inner ring retaining seal 8 (right side in the figure). Therefore, it is possible to effectively prevent excessive discharge of lubricating oil from the bearing through the oil drain gap 29.

[0184] Furthermore, in this rolling bearing 1, by making Figure 4 The sealing fixing surface 16 shown and Figure 2 The sealing sliding contact surfaces 15 shown are symmetrical shapes with the same outer diameter, thus making... Figure 1 The shape of the inner ring 3 shown is symmetrical with respect to the right-angled plane of the shaft. Therefore, when manufacturing the inner ring 3, the sealing fixing surface 16 and the sealing sliding contact surface 15 can be machined in the same process, resulting in low cost. In addition, when assembling the rolling bearing 1, there is no need to distinguish the inside and outside orientation of the inner ring 3, thus providing excellent workability.

[0185] In addition, such as Figure 1 As shown, the rolling bearing 1 uses a metal shield plate that does not contact the inner circumference of the outer ring 2 as the inner ring fixing seal component 8, thus enabling the bearing's rotational resistance to be suppressed to a small extent.

[0186] Furthermore, in this rolling bearing 1, by making Figure 2 The cross-sectional shape of the sealing groove 11 shown is... Figure 4 The cross-sectional shape of the circumferential groove 12 shown is symmetrical, thus making Figure 1 The outer ring 2 shown is symmetrical about the plane perpendicular to the shaft, so when manufacturing the outer ring 2, the sealing groove 11 and the circumferential groove 12 can be machined in the same process, resulting in low cost. In addition, when assembling the rolling bearing 1, there is no need to distinguish the inside and outside orientation of the outer ring 2, thus providing excellent workability.

[0187] In the above embodiments, such as Figure 4As shown, the edge bend 28 formed by bending the annular plate portion 27 radially outward toward the axially inward is described as an example of a cylindrical edge bend 28 extending from the radially outward end of the annular plate portion 27 toward the axially inward with a certain diameter. However, as... Figure 5 As shown, a frustum-shaped edge bend 28, with its diameter gradually increasing from the radially outer end of the annular plate portion 27 toward the axially inner side, can also be used. Figure 5 In the middle, the radially outer portion of the edge bend 28 is received within the circumferential groove 12 of the inner circumference of the outer ring 2. Even when using Figure 5 The structure shown can also efficiently catch the lubricating oil inside the bearing that moves along the inner circumference of the outer ring shoulder 10 toward the inner ring fixed sealing member 8 (right side in the figure) with the edge bending portion 28, thus effectively preventing the lubricating oil inside the bearing from being excessively discharged from the oil drain gap 29.

[0188] As the edge bend 28 formed by bending the radially outer end of the annular plate portion 27 towards the axially inner side, it can be adopted as follows: Figure 6 The edge-bent portion 28, which has a crank-shaped cross-section as shown, is composed of a cylindrical portion 36 and an annular plate portion 37 extending radially outward from the front end of the cylindrical portion 36. Alternatively, it can be as shown... Figure 7 The conical edge bend 28, whose diameter gradually decreases from the radially outer end of the annular plate portion 27 toward the axially inner side, as shown, can also be used as... Figure 8 As shown, the edge bend 28, which connects the radially outer end of the annular plate portion 27 to the cylindrical portion 39 via the truncated cone portion 38, can also employ, as shown in the figure... Figure 9 As shown, the edge bend 28 connects to the cylindrical portion 41 from the radially outer end of the annular plate portion 27 via the arc-shaped R portion 40. Figures 6-9 In any of the variations shown, since at least a portion of the edge bend 28 is received in the circumferential groove 12 of the inner circumference of the outer ring 2, the edge bend 28 can efficiently catch the lubricating oil inside the bearing that moves along the inner circumference of the outer ring shoulder 10 toward the inner ring fixed seal member 8 (right side in the figure), and as shown... Figure 10 Compared to the case where the entire edge bend 28 is arranged on the outside of the circumferential groove 12 as shown, it is possible to effectively prevent excessive discharge of lubricating oil from the bearing through the oil drain gap 29.

[0189] In the above embodiments, an example is given of using a component in which rubber 18 is vulcanized and bonded to a metal core 17 as the outer ring fixing sealing component 7. However, a shielding plate formed by stamping a metal sheet (for example, a component with an interchangeable inner diameter side and outer diameter side of the inner ring fixing sealing component 8 in the above embodiments) can also be used as the outer ring fixing sealing component 7. In this case, a structure can be formed where the inner circumference of the outer ring fixing sealing component 7 does not slide in contact with the outer circumference of the inner ring 3, and an annular oil supply gap 23 is formed between the inner circumference of the outer ring fixing sealing component 7 and the outer circumference of the inner ring 3.

[0190] Furthermore, in the above embodiment, an example is given of using a shield formed by stamping a metal sheet as the inner ring fixing seal member 8. However, a component that is vulcanized and bonded to a metal core can also be used as the inner ring fixing seal member 8. In this case, for example, a component with an interchangeable inner diameter side and outer diameter side of the outer ring fixing seal member 7 in the above embodiment can be used as the inner ring fixing seal member 8, and the gap between adjacent protrusions 24 in the circumferential direction can be used as the oil discharge gap 29.

[0191] The rolling bearing and rotating machinery involved in an embodiment as an example of the second invention will be described based on the accompanying drawings.

[0192] Figure 13 The rotating machinery shown includes: a housing 100, a rotating part 101 that rotates relative to the housing 100, a rolling bearing 50 that supports the rotating part 101 so that it can rotate freely relative to the housing 100, and an oil supply part 102 that supplies oil to the rolling bearing 50.

[0193] The rolling bearing 50 comprises an inner component 51, an outer component 52 surrounding the inner component 51, a plurality of rolling elements 53 housed between the inner component 51 and the outer component 52, a cage 54 holding the rolling elements 53, a protective member 55 mounted on the outer component 52, and an oil slinger 56 mounted on the inner component 51. The inner diameter of the rolling bearing 50 can be, for example, in the range of 30 mm to 45 mm.

[0194] The rolling element 53, the cage 54, the shield 55 and the oil slinger 56 are arranged in an annular space 57 formed by the outer periphery of the inner component 51 and the inner periphery of the outer component 52.

[0195] Here, the direction along the bearing center axis of the rolling bearing 50 is referred to as the "axial direction," the direction perpendicular to the bearing center axis is referred to as the "radial direction," and the direction extending circumferentially around the bearing center axis is referred to as the "circumferential direction." Furthermore, in the radial direction, the side closer to the bearing center axis is referred to as the "radial inner side," and conversely, the side farther from the bearing center axis is referred to as the "radial outer side." Figure 13In this context, the axial direction corresponds to the left-right direction, and the radial direction corresponds to the up-down direction.

[0196] The housing 100 is composed of an outer shell that is stationary relative to the rotating part 101. The rotating part 101 is composed of a shaft that rotates by an input torque. For example, when the rotating machinery is an electric axle assembly for driving a vehicle, the rotating part 101 can be a motor shaft or a drive shaft of a reducer, and the housing 100 can be a motor housing or a reducer housing.

[0197] The oil supply section 102 supplies oil to the axial side of the rolling bearing 50. The oil reaches the outer periphery of the end of the inner component 51 on the axial side. In the illustrated example, a splash lubrication method is envisioned, and the oil supply section 102 is used as a pipe that allows oil to fall towards the side surface of the rolling bearing 50 on the axial side. In the case of an oil bath lubrication method, an oil reservoir section can be used as the oil supply section, which accumulates oil to the level where the lower part of the rolling element 53, which is the lowest in the revolution trajectory of the rolling element 53, is submerged in oil. The oil supply section 102 can supply oil in liquid form as in oil bath lubrication or splash lubrication, or in mist form as in drip lubrication or spray lubrication. Furthermore, in Figure 13 In the diagram, the movement of oil is schematically represented by arrows without reference numerals. The atmosphere surrounding the rolling bearing 50 is typically air. The oil supply unit 102 supplies a small amount of oil, which mixes with the atmosphere and enters the annular space 57, becoming a lubricating fluid that aids in the lubrication and cooling of the rolling elements 53, etc.

[0198] The inner component 51 is composed of a track ring that includes a first track surface 58 on its outer periphery and a shoulder 59 that defines the outer diameter of the inner component 51. The inner diameter surface of the inner component 51 engages with the rotating part 101.

[0199] The outer component 52 is composed of a shoulder 61 that includes a second track surface 60 on its inner circumference and defines the inner diameter of the outer component 52, a circumferential groove 62 formed at a position away from the second track surface 60 on one axial side, and a track ring with a cutout 63 at a position away from the second track surface 60 on the other axial side, the diameter of which is larger than that of the shoulder 61. The outer diameter surface of the outer component 52 fits into the housing 100.

[0200] The rolling element 53 is composed of balls that roll on the first track surface 58 and the second track surface 60.

[0201] Rolling bearing 50 is configured as a deep groove ball bearing.

[0202] The maximum rotational speed of the rolling bearing 50, which accompanies the rotation of the rotating part 101, is set to a value of dmn of 650,000 or higher. Here, the dmn value is calculated by [{outer diameter of the rolling bearing (mm) + inner diameter of the rolling bearing (mm)} / 2] × rotational speed n (min⁻¹). The outer diameter of the rolling bearing 50 is defined by the outer diameter surface of the outer component 52. The inner diameter of the rolling bearing 50 is defined by the inner diameter surface of the inner component 51. The rotational speed n is defined by the rotational speed per minute of the inner component 51.

[0203] like Figure 13 , Figure 14 As shown, the cage 54 is made of a resin component that has a seamless axial side opposite to one side of the plurality of rolling elements 53. Figure 13 The annular portion 64 extends circumferentially from the position on the right side (center), and multiple pairs of claw portions 65 and 66 extend axially from the annular portion 64. A pair of claw portions 65 and 66 are formed on the radially inner side, radially outer side, and axial side (center to the right). Figure 13 The space 67, which is an opening on the left side, extends from the annular portion 64. The space 67 is arranged at equal intervals at multiple locations in the circumferential direction of the retainer 54.

[0204] like Figures 13-15 As shown, the rolling element 53 is disposed in space 67. Space 67 is formed by opposing portions of a pair of claw portions 65 and 66 that clamp the rolling element 53 in the middle and are circumferentially opposite, and a portion of an annular portion 64. The pair of claw portions 65 and 66 have front ends located axially closer to the center of the rolling element 53. The minimum width of the opening formed by the front ends of these claw portions 65 and 66 on the side surface of the cage 54 on the axial side is smaller than the diameter of the rolling element 53. The rolling element 53 is disposed in the aforementioned space by being forced through the front ends of the pair of claw portions 65 and 66.

[0205] The annular portion 64 is configured to be radially spaced from the shoulder portion 61 on the axially opposite side of the outer component 52. The side surface 68 on the axially opposite side of the annular portion 64 is a radially extending planar surface and is located on the axially opposite side in the cage 54. The claw portions 65 and 66 are located on the axially opposite side in the cage 54. The axial length of the claw portions 65 and 66, extending from the circumference of the resin portion forming the annular portion 64, is shorter than that of the rolling element 53.

[0206] The cage 54 is guided radially and axially by a plurality of rolling elements 53. Therefore, as... Figure 13 As shown, the retainer 54 is configured to be in a non-contact state with the inner component 51, the outer component 52, the shield 55 and the oil slinger 56 respectively.

[0207] Most of the cage surface forming space 67 is a guide surface that runs along an imaginary sphere and is in contact with the rolling element 53. The geometric center O of space 67 is the center of the aforementioned imaginary sphere. Furthermore, in the illustration, the center O of space 67 coincides with the center of the rolling element 53. Additionally, in... Figure 15 In the diagram, the vertical direction corresponds to the axial direction, and the horizontal direction corresponds to the circumferential direction.

[0208] like Figure 15 As shown, the claw portions 65 and 66 include an oil inflow path 67a facing the space 67. The oil inflow path 67a is a flow path that forms a groove space between the rolling element 53 and the rolling element 53, in which the rolling element 53 cannot enter. During operation of the rolling bearing 50, as oil enters between the oil inflow path 67a and the rolling element 53, it promotes lubrication and cooling of the rolling element 53 and its surroundings.

[0209] The oil inflow path 67a is located on an imaginary plane passing through the center of the multiple rolling elements 53. The rolling elements 53 rotate fastest on and near this imaginary plane, so the oil inflow path 67a is preferably configured to promote lubrication.

[0210] like Figure 14 , Figure 15 As shown, in the cage 54, the two claw portions 65 and 66 located between adjacent rolling elements 53 in the circumferential direction are recessed to the opposite axial direction. Here, the minimum axial thickness from the concave end face 69 located on the opposite axial side between the two claw portions 65 and 66 to the side surface of the cage 54 on the opposite axial side is defined as 'a'. The axial thickness from the bottom P of the bag located on the opposite axial side in the space 67 to the side surface of the cage 54 on the opposite axial side is defined as 'b'. The minimum distance between the concave end face 69 and the imaginary plane passing through the center of the plurality of rolling elements 53 is defined as 'c'. The cage 54 satisfies a > b and c > 0. Therefore, the annular strength of the cage 54 can be ensured, and the mass of the claw portions 65 and 66 can be reduced to reduce the centrifugal force acting on the claw portions 65 and 66, thereby suppressing deformation of the cage 54 during high-speed rotation and preventing interference between the claw portions 65 and 66 and other components such as the rolling elements 53.

[0211] The resin material forming the retainer 54 can be, for example, a material containing polyetheretherketone (PEEK) or polyphenylene sulfide (PPS) as the main component, or a composite material incorporating reinforcing fibers such as carbon or glass into a suitable matrix resin. The axial thicknesses a, b, and c are determined based on the strength of the resin material forming the retainer 54, ensuring that a > b and c > 0. For example, when polyamide resin is used as the main component, setting the axial thickness b to a value between 1 / 70 and 1 / 30 of the retainer PCD ensures rigidity at the relatively thin bottom P of the bag, effectively preventing deformation during high-speed rotation. In this case, when the weld portion of the retainer 54 generated during injection molding is positioned at the minimum axial thickness a, setting the minimum axial thickness a to a value between 1 / 62 and 1 / 26 of the retainer PCD ensures strength at the weld portion. Furthermore, the retainer PCD refers to the diameter of an imaginary circle extending circumferentially through the center O of each space 67.

[0212] like Figure 13 As shown, the shield 55 protrudes from the inner diameter surface of the outer component 52 toward the outer diameter surface of the inner component 51 at a position axially away from the rolling element 53 and the cage 54. A first oil passage 70 is formed between the shield 55 and the inner component 51. The first oil passage 70 is an inlet for drawing lubricating fluid, such as oil, from the annular space 57 into the space region of the annular space 57 that is closer to the rolling element 53 than the shield 55, relative to the annular space 57, which extends from the axial side to the gap between the shield 55 and the inner component 51.

[0213] When the rolling bearing 50, whose inner component 51 rotates, rotates, the lubricating fluid such as oil is agitated by the rolling elements 53 and the cage 54. The lubricating fluid, such as oil, directed towards the axial side relative to the rolling elements 53 and the cage 54 is received by the shielding member 55, thus reducing the impact of the air curtain on the axial side surface of the rolling bearing 50. As a result, the oil supplied from the oil supply section 102 towards the axial side relative to the rolling bearing 50 easily reaches the first oil port 70.

[0214] The oil slinger ring 56 protrudes from the outer diameter surface of the inner component 51 toward the inner diameter surface of the outer component 52 at a position axially away from the rolling elements 53 and the cage 54. A second oil passage 71 is formed between the oil slinger ring 56 and the outer component 52. The second oil passage 71 is a space through which oil can pass, serving as an outlet for discharging lubricating fluids, such as oil, that have been drawn into the annular space 57 after entering through the first oil passage 70 and are located axially away from the rolling elements 53 and the cage 54, out of the annular space 57.

[0215] The oil slinger 56 exerts centrifugal force on the lubricating fluid, such as oil, within the annular space 57, thereby promoting the discharge of the lubricating fluid from the second oil port 71. As a result, the back pressure of the second oil port 71 relative to the first oil port 70 is suppressed. Due to the pressure difference between the first oil port 70 and the second oil port 71, the lubricating fluid, such as oil, that lubricates and cools the rolling elements 53, is drawn towards the second oil port 71, and oil and air supplied from the oil supply section 102 are easily drawn in from the first oil port 70.

[0216] The protective element 55 and the oil slinger ring 56 are each formed from a single metal sheet. Here, a steel sheet is used as the metal sheet. For example, SPC material specified in the JIS standard can be used as the steel sheet.

[0217] The shield 55 is composed of a rolled edge plate portion 72 held in the circumferential groove portion 62 of the outer component 52, a front end plate portion 73 of the shoulder portion 59 closest to the inner component 51 in the shield 55, an inner diameter side tapered plate portion 74 extending from the axial side of the front end plate portion 73 in a direction inclined to the radially outward, a middle plate portion 75 extending radially from the inner diameter side tapered plate portion 74, and an outer diameter side tapered plate portion 76 extending from the inner diameter side of the rolled edge plate portion 72 in a direction inclined to the axial side to the middle plate portion 75.

[0218] The protective member 55 is installed on the outer member 52 by riveting the rolled edge plate portion 72 to the circumferential groove portion 62 of the outer member 52.

[0219] The front end plate 73 is configured to be radially spaced from the shoulder 59 on the axial side of the inner component 51. The inner circumference of the front end plate 73 defines the inner diameter of the shield 55. The inner diameter of the shield 55 is set to be smaller than or equal to the inner diameter of the cage 54. Therefore, the entire cage 54 is covered by the shield 55 from the axial side. When the rolling bearing 50 rotates, most of the lubricating fluid, such as oil, which is stirred towards the axial side by the rolling elements 53 and the cage 54, is received by the shield 55.

[0220] The inner diameter-side tapered plate portion 74 extends radially outward from the front end plate portion 73 of the inner diameter of the defined shield 55 toward the axial side, thereby expanding the space between the inner diameter-side tapered plate portion 74 and the shoulder portion 59 compared to the space between the front end plate portion 73 and the shoulder portion 59 on the axial side of the inner component 51. Therefore, oil supplied from the oil supply portion 102 can easily enter the first oil port 70 between the inner diameter-side tapered plate portion 74 and the shoulder portion 59.

[0221] The front end plate portion 73 is cylindrical, extending axially in a circumferential direction from the inner diameter side tapered plate portion 74. Therefore, lubricating fluid such as oil entering the first oil port 70 can easily flow along the inner circumference of the front end plate portion 73 and the shoulder portion 59 toward the rolling element 53.

[0222] The distance between the shield 55 and the cage 54 is greater than the distance between the shield 55 and the rolling element 53. The annular portion 64 is positioned on the opposite side of the axial direction relative to the rolling element 53, while the cage 54 is positioned further away from the shield 55 than the rolling element 53. Since the annular portion 64 is not present between the shield 55 and the rolling element 53, the space between them is correspondingly wider. Therefore, lubricating fluid such as oil drawn in from the first oil port 70 enters and diffuses into the wider space between the shield 55 and the rolling element 53, easily reaching the rolling element 53. Furthermore, for the agitated lubricating fluid such as oil, the flow rate towards the opposite side of the axial direction is reduced due to the obstruction of the annular portion 64, while the flow rate towards one side of the axial direction is increased in the wider space. If this lubricating fluid towards one side of the axial direction is received by the shield 55, its flow direction changes, and it diffuses into the wider space. When the lubricating fluid, such as oil, received by the shield 55 flows towards the outer component 52, it is guided by the outer diameter tapered plate portion 76 and easily reaches the rolling element 53. Conversely, when the lubricating fluid, such as oil, received by the shield 55 flows towards the inner component 51, it merges with the lubricating fluid that enters the relatively wide space between the shield 55 and the rolling element 53 from the first oil port 70, and is guided by the inner diameter tapered plate portion 74 and the front end plate portion 73, easily reaching the rolling element 53.

[0223] The oil slinger 56 is composed of a cylindrical plate portion 77 that fits into the outer periphery of the inner component 51 on the other side of the axial direction, and a side plate portion 78 that protrudes radially outward from the other side of the cylindrical plate portion 77 on the other side of the axial direction.

[0224] The oil slinger 56 is installed on the inner part 51 by pressing the cylinder plate portion 77 into the inner part 51.

[0225] The cylindrical plate portion 77 is configured to be radially spaced from the inner circumference of the annular portion 64. The side plate portion 78 is configured to be axially spaced from the side surface 68 on the other side of the annular portion 64.

[0226] The cylindrical plate portion 77 is located between the inner component 51 and the annular portion 64, and the radial distance g1 between the cylindrical plate portion 77 and the annular portion 64 is narrower than the radial distance between the annular portion 64 and the inner component 51. Lubricating fluids such as oil that wish to enter the space between the annular portion 64 and the cylindrical plate portion 77 from near the rolling element 53 are blocked by the cylindrical plate portion 77 and have difficulty passing through this space. When the rolling bearing 50 rotates at high speed, the lubricating fluids such as oil that come into contact with the outer periphery of the cage 54, the outer periphery of the inner component 51, and the oil slinger ring 56 are strongly propelled radially outward by centrifugal force. Therefore, the lubricating fluids tend to concentrate towards the outer component 52 side, and the oil tends to thin between the cage 54 and the inner component 51. Thus, the difficulty for lubricating fluids such as oil to pass through the space between the annular portion 64 and the cylindrical plate portion 77 from near the rolling element 53 is advantageous for the lubrication and cooling of the rolling element 53 and the first track surface 58.

[0227] The radial distance g1 between the cylindrical plate portion 77 and the annular portion 64 is set to be smaller than the axial distance g2 between the side surface 68 on the other side of the axial direction of the annular portion 64 and the side plate portion 78. Therefore, the flow path cross-sectional area between the side surface 68 on the other side of the axial direction of the annular portion 64 and the side plate portion 78 is larger than the flow path cross-sectional area between the cylindrical plate portion 77 and the annular portion 64.

[0228] All the lubricating fluid, such as oil, passes through the space between the cylindrical plate portion 77 and the annular portion 64 on the other side of the axial direction and enters between the side surface 68 and the side plate portion 78 on the other side of the axial direction of the annular portion 64. At this time, the lubricating fluid is guided by the side plate portion 78, and the flow direction changes radially outward. In addition, when the lubricating fluid, such as oil, enters from the space between the cylindrical plate portion 77 and the annular portion 64, which has a relatively narrow flow path cross-section, between the side surface 68 and the side plate portion 78 on the other side of the axial direction of the annular portion 64, which has a relatively wide flow path cross-section, the pressure decreases and the velocity increases radially outward. Due to this acceleration, the lubricating fluid, such as oil, passing through the space between the side surface 68 and the side plate portion 78 on the other side of the axial direction of the annular portion 64 can be easily discharged from the second oil port 71.

[0229] Furthermore, between the side surface 68 and the side plate portion 78 on the other side of the axial direction of the annular portion 64, lubricating fluid such as oil that is in contact with the side surface 68 and the side plate portion 78 is sent radially outward due to centrifugal force. The lubricating fluid such as oil that is in contact with the side surface 68 or the side plate portion 78 cannot escape from between the side surface 68 and the side plate portion 78, and centrifugal force is applied by the two portions 68 and 78 from the side surface 68 and the side plate portion 78 to the second oil port 71 that is thrown out radially outward.

[0230] Furthermore, if the axial distance g2 between the side surface 68 on the other side of the annular portion 64 and the side plate portion 78 is too wide, the flow of lubricating fluid such as oil between the side surface 68 and the side plate portion 78 will be disordered, thus reducing the efficiency of conveying lubricating fluid such as oil using centrifugal force. Therefore, the axial distance g2 is set to, for example, 1 mm or more and 3 mm or less.

[0231] The radial distance g3 between the outer periphery of the side plate portion 78 and the outer component 52 is set to be greater than the axial distance g2 between the side surface 68 on the other side of the annular portion 64 and the side plate portion 78. Therefore, the flow path cross-sectional area between the outer periphery of the side plate portion 78 and the outer component 52 is greater than the flow path cross-sectional area between the side surface 68 on the other side of the annular portion 64 and the side plate portion 78.

[0232] As lubricating fluid, such as oil, passes radially outward between the side surface 68 and the side plate portion 78 on the axial side of the annular portion 64 (where the flow path cross-section is relatively narrow) and enters between the outer periphery of the side plate portion 78 (where the flow path cross-section is relatively wide) and the outer component 52, the pressure decreases and the velocity increases radially outward. Therefore, lubricating fluid, such as oil, passing radially outward between the side surface 68 and the side plate portion 78 on the axial side of the annular portion 64 is easily discharged from the second oil port 71.

[0233] The cutout 63 of the outer component 52 is positioned radially opposite the side plate portion 78 and is larger in diameter than the shoulder portion 61. The second oil passage 71 is also widened radially outwards, thus preventing the outer diameter of the side plate portion 78 from becoming a small diameter. Correspondingly, the space between the side plate portion 78 and the side surface 68 on the other axial side of the annular portion 64 extends radially outwards, which is advantageous for enhancing the aforementioned centrifugal effect.

[0234] The annular portion 64 and the shoulder 61 of the outer member 52 are radially spaced apart, and the side plate portion 78 is provided with a diameter smaller than that of the shoulder 61. This allows lubricating fluid, such as oil, flowing from near the rolling element 53 between the shoulder 61 and the outer periphery of the cage 54 to the other axial side to reach the second oil port 71 without colliding with the side plate portion 78 axially. Therefore, lubricating fluid, such as oil, passing through the outer periphery of the outer member 52 and the cage 54 easily flows towards the second oil port 71. Furthermore, lubricating fluid present near the second oil port 71 easily exits from the second oil port 71. In addition, in the illustrated example, to maximize the centrifugal force between the side surface 68 on the other axial side of the annular portion 64 and the side plate portion 78, the outer diameter of the side plate portion 78 is set to be the same size as the outer diameter of the annular portion 64.

[0235] The lubricating fluid, such as oil, passing through the side surface 68 and side plate 78 on the other side of the axial direction of the annular portion 64 merges with the lubricating fluid passing through the annular portion 64 and shoulder 61 on the other side of the axial direction, and is discharged from the second oil port 71. When the rolling bearing 50 rotates at high speed, if the momentum of the lubricating fluid passing through the side surface 68 and side plate 78 is strong, it can reach the cut portion 63. The arriving lubricating fluid collides with the cut portion 63 and diffuses towards the second oil port 71, or is guided by the cut portion 63 to circulate counterclockwise between the cut portion 63 and the outer periphery of the annular portion 64 and towards the second oil port 71. Even if the lubricating fluid collides with the cut portion 63, because the cut portion 63 forms a radial step difference relative to the shoulder 61, it can still suppress the flow towards the outer periphery of the shoulder 61 and the annular portion 64.

[0236] The side plate portion 78 contacts the atmosphere surrounding the rolling bearing 50 on its axially opposite side surface. As the rolling bearing 50 rotates with the inner component 51 rotating, the atmosphere in contact with the axially opposite side surface of the side plate portion 78 is propelled radially outward by centrifugal force. This flow blows away the fluid present near the second oil port 71 outside the annular space 57, reducing its pressure and thus promoting the discharge of lubricating fluids such as oil from the second oil port 71.

[0237] When the rolling bearing 50 is configured as a ball bearing, when the amount of oil drawn in from the first oil port 70 is small, whether the lubrication between the rolling element 53 and the track surfaces 58 and 59 is sufficient can be studied, for example, by using the test results shown in Non-Patent Documents 1 and 2 and the research conclusions based on the estimation method of friction torque shown in Non-Patent Document 3, which is the reduction of rolling viscous resistance φr.

[0238] The reduction in rolling viscous resistance φr is calculated using the following equation 1.

[0239] [Formula 1]

[0240]

[0241] T: The travel period of the ball (rolling element) in milliseconds.

[0242] ν: Kinematic viscosity of oil (mm² / s)

[0243] a: Radius of the major axis of the contact ellipse (mm)

[0244] k: Oil volume (ml / min)

[0245] According to the test examples in Non-Patent Literature 1 and 2, under test conditions of oil supply rate of 70 ml / min and 100 ml / min, adequate lubrication was maintained up to the maximum speed under the test conditions. On the other hand, under the test condition of 40 ml / min, insufficient lubrication occurred at speeds lower than the maximum speed. If the reduction in rolling viscous resistance φr under the above test conditions is calculated, then under the test condition of oil supply rate of 40 ml / min, φr = 0.288; under the test condition of oil supply rate of 70 ml / min, φr = 0.505; and under the test condition of oil supply rate of 100 ml / min, φr = 0.721. Therefore, it can be considered that adequate lubrication can be maintained when φr ≥ 0.505.

[0246] That is, the amount of oil drawn in from the first oil port 70 is set as k, the kinematic viscosity of the oil in the operating environment is set as ν, the passing period of the rolling element 53 at the desired dmn value of the rolling bearing 50 in the operating environment is set as T, and the major axis radius of the contact ellipse in the contact portion between the rolling element 53 and the first track surface 58 or the second track surface 60 in the operating environment is set as a to calculate φr. For example, if φr ≥ 0.505 is satisfied when the dmn value of the rolling bearing 50 is 650,000 or more, it is considered that sufficient lubrication can be maintained under the specified value.

[0247] Figures 13-15 The rolling bearing 50 shown is a rolling bearing as described above, comprising: an inner part 51 having a first track surface 58, an outer part 52 having a second track surface 60, a plurality of rolling elements 53 disposed between the first track surface 58 and the second track surface 60, and a cage 54 for holding the plurality of rolling elements 53.

[0248] In particular, the rolling bearing 50 also includes: a protective member 55, located on the axial side relative to the rolling elements 53 and the cage 54 ( Figure 13 At a position away from the left side (in the middle), it protrudes from the inner diameter surface of the outer component 52 toward the outer diameter surface of the inner component 51; and the oil slinger ring 56, on the other side axially relative to the rolling element 53 and the cage 54 ( Figure 13At a position away from the right side (in the middle), the inner component 51 protrudes from the outer diameter surface toward the inner diameter surface of the outer component 52. The space between the shield 55 and the inner component 51 becomes a first oil inlet 70 for drawing in oil, and the space between the oil slinger 56 and the outer component 52 becomes a second oil inlet 71 for expelling the oil drawn in from the first oil inlet 70. Thus, when the rolling bearing 50 rotates with the inner component 51 rotating, the oil and other lubricating fluids that are stirred by the rolling elements 53 and the cage 54 toward the axial side are received by the shield 55, thereby reducing the influence of the air curtain on the side surface of the rolling bearing 50 on the axial side. This makes it easier for the oil supplied to the axial side of the rolling bearing 50 to reach the first oil inlet 70. On the other hand, on the other side of the axial direction of the rolling bearing 50, the oil that has lubricated and cooled the rolling elements 53 can be centrifuged by the oil slinger 56 to promote the discharge of oil from the second oil inlet 71. This further suppresses the back pressure of the second oil inlet 71 relative to the first oil inlet 70 and makes it easier to draw in oil from the first oil inlet 70. The rolling bearing 50 can function as a centrifugal pump by reducing the effects of air curtain and suppressing the back pressure of the second oil port 71 relative to the first oil port 70. This prevents oil from flowing back through the first oil port 70 and draws oil drawn from the first oil port 70 towards the second oil port 71, allowing the oil that lubricates and cools the rolling elements 53 to be discharged from the second oil port 71. Increasing the dmn value (bearing rotation speed) of the rolling bearing 50 enhances the centrifugal pumping effect. Thus, the rolling bearing 50, equipped with a shielding member 55 and an oil slinger ring 56 for effective centrifugal pumping at high speeds, can increase the bearing rotation speed when lubrication is insufficient without requiring a large or complex electric axle assembly.

[0249] In addition, in this rolling bearing 50, the cage 54 has an annular portion 64 extending circumferentially on the other side of the axial direction relative to the plurality of rolling elements 53, and the oil slinger 56 has a side plate portion 78 that is axially spaced apart from the side surface 68 on the other side of the annular portion 64. This allows oil to flow between the annular portion 64 and the side plate portion 78, and the oil is centrifugally transported from the two portions 68 and 78 to the second oil port 71 in a manner that prevents the oil from escaping between them.

[0250] Furthermore, in this rolling bearing 50, the oil slinger 56 has a cylindrical plate portion 77 that is fitted into the inner component 51 in a manner that is radially spaced from the annular portion 64. The side plate portion 78 protrudes radially outward from the other side of the axial direction of the cylindrical plate portion 77. The radial distance g1 between the cylindrical plate portion 77 and the annular portion 64 is set to be smaller than the axial distance g2 between the side surface 68 on the other side of the axial direction of the annular portion 64 and the side plate portion 78. As a result, oil is difficult to pass between the annular portion 64 and the cylindrical plate portion 77. Therefore, when the rolling bearing 50 rotates at high speed, the oil is more likely to become thinner between the inner circumference of the cage 54 and the inner component 51, so that oil can be easily supplied to the rolling element 53.

[0251] In addition, in this rolling bearing 50, the radial distance g3 between the outer periphery of the side plate portion 78 and the outer component 52 is set to be greater than the axial distance g2 between the side surface 68 on the other side of the axial direction of the annular portion 64 and the side plate portion 78, thereby making it easier for oil passing through the space between the side surface 68 on the other side of the axial direction of the annular portion 64 and the side plate portion 78 to be discharged from the second oil port 71.

[0252] Furthermore, in this rolling bearing 50, the outer component 52 has a shoulder 61 that is radially spaced from the annular portion 64, and a cutout 63 that is radially opposite to the side plate portion 78 and has a diameter larger than that of the shoulder 61. The side plate portion 78 has a smaller diameter than that of the shoulder 61. This allows the diameter of the side plate portion 78 to be prevented from becoming smaller by radially enlarging the second oil passage 71 through the cutout 63, and also allows the oil passing between the outer component 52 and the outer periphery of the cage 54 to easily flow towards the second oil passage 71.

[0253] In addition, in this rolling bearing 50, the inner diameter of the shield 55 is set to be smaller than the inner diameter of the cage 54, and the entire cage 54 and most of the multiple rolling elements 53 are covered from the axial side by the shield 55. Therefore, the shield 55 can receive most of the oil that is stirred by the cage 54 and the rolling elements 53 and directed towards the axial side, so as to prevent it from flowing back to the first oil port 70.

[0254] In addition, in this rolling bearing 50, the cage 54 is positioned further away from the shield 55 on the axial side than the rolling element 53, and the space between the shield 55 and the rolling element 53 is set to be wider, so that oil can diffuse in the space between the two 55 and 53 and easily reach the rolling element 53.

[0255] Furthermore, in this rolling bearing 50, the shield 55 has a front end plate portion 73 that is closest to the innermost component 51 in the shield 55 and an inner diameter side tapered plate portion 74 that extends from the axial side of the front end plate portion 73 in a direction inclined to the radially outward direction. This allows oil supplied to the axial side of the rolling bearing 50 to easily enter the first oil passage 70, and allows oil received by the shield 55 to easily reach the rolling element 53.

[0256] Furthermore, in this rolling bearing 50, the cage 54 is made of a resin component, which has an annular portion 64 extending in the circumferential direction and multiple pairs of claw portions 65, 66 extending axially from the annular portion 64 in such a way as to form a space 67 opening to the radially inward, radially outward, and axially. The rolling elements 53 are made of balls disposed in the space 67. The claw portions 65, 66 located between adjacent rolling elements 53 in the circumferential direction are recessed to the other axial side. The distance from the recessed end face 69 located on the other axial side between the claw portions 65, 66 to the other axial side of the cage 54 is... The minimum axial thickness up to the side surface of the ring portion 64 (the side surface 68 on the other side of the axial direction) is set as a, the axial thickness from the bottom P of the bag located on the other side of the axial direction in the space 67 to the side surface of the cage 54 on the other side of the axial direction (the side surface 68 on the other side of the axial direction of the ring portion 64) is set as b, and the minimum distance between the imaginary plane passing through the center of the plurality of rolling elements 53 and the concave end face 69 is set as c. At this time, by satisfying a > b and c > 0, the deformation of the cage 54 caused by centrifugal force during high-speed rotation can be suppressed, so the rolling bearing 50 can be made into a ball bearing suitable for high-speed rotation applications.

[0257] Furthermore, the rotating machinery according to the embodiment, by having a rolling bearing 50, a rotating part 101 supported by the rolling bearing 50, and an oil supply part 102 that supplies oil to one side axially relative to the rolling bearing 50, can draw oil from the first oil port 70 when the rolling bearing 50 is rotating at high speed. Therefore, even without an oil supply part that can control the amount of oil supply with high precision, it can still increase the rotational speed of the bearing that is lacking lubrication and perform high-speed operation of the rotating part 101.

[0258] In this embodiment, an example is shown where the space from the first oil port 70 to the rolling element 53 is axially straight. However, a circumferential groove can also be formed on the outer periphery of the end on the axial side of the inner component, forming a labyrinthine gap between the circumferential groove and the front end plate of the shield. Additionally, an example is shown where the shield 55 is made of a metal plate. However, it can also be a seal with a resilient sealing lip. For example, it can be configured as a non-contact seal where the sealing lip is arranged to form a labyrinthine gap between the sealing lip and the circumferential groove of the inner component as described above. The metal core of the seal can also be formed in a shape corresponding to the shield 55.

[0259] Alternatively, the annular portion of the cage can be positioned on one side relative to the rolling elements. In this case, since the lubricating fluid, such as oil, stirred by the rolling elements is blocked by the annular portion and is difficult to reach the first oil port, it is advantageous to reduce the effect of the air curtain. However, the downside is that the oil drawn in from the first oil port is blocked by the annular portion and is difficult to reach the rolling elements; and because the gap between the oil slinger ring and the cage is widened, even if centrifugal force is applied to the lubricating fluid, such as oil, through the oil slinger ring, the lubricating fluid is difficult to reach the second oil port, and the centrifugal pump effect is weakened. Therefore, it is sufficient to consider these advantages and disadvantages to determine which side of the cage's annular portion is positioned relative to the rolling elements.

[0260] In addition to deep groove ball bearings, the present invention can also be applied to angular contact ball bearings and roller bearings.

[0261] The embodiments disclosed herein should be considered exemplary in all respects and not restrictive. The scope of the invention is defined by the claims, not the foregoing description, and is intended to include all modifications within the meaning and scope equivalent to the claims.

[0262] Explanation of reference numerals in the attached figures:

[0263] 1…rolling bearing; 2…outer ring; 3…inner ring; 4…bearing space; 5…rolling element; 7…outer ring fixed seal component; 8…inner ring fixed seal component; 11…seal fixing groove; 12…circumferential groove; 15…seal sliding contact surface; 16…seal fixing surface; 21…seal lip; 22…axial end face; 23…oil supply gap; 24…protrusion; 26…fitting cylinder portion; 27…annular plate portion; 28…edge bend portion; 29…oil discharge gap; 50…rolling bearing; 51…inner component; 52…outer component Components; 53…rolling element; 54…cage; 55…protective element; 56…oil slinger ring; 58…first track surface; 60…second track surface; 61…shoulder; 63…cutout; 64…annular part; 65, 66…claw; 67…space; 68…side surface on the other side of the axial direction; 69…concave end face; 70…first oil port; 71…second oil port; 73…front end plate; 74…inner diameter side tapered plate; 77…cylinder plate; 78…side plate; 101…rotating part; 102…oil supply part.

Claims

1. A rolling bearing, comprising: Outer ring (2); The inner ring (3) is disposed radially inside the outer ring (2); Multiple rolling elements (5) are fitted into an annular bearing space (4) formed between the outer ring (2) and the inner ring (3); and A pair of sealing components (7, 8) respectively cover one axial end opening and the other axial end opening of the bearing space (4). The rolling bearing is characterized in that... One of the pair of sealing components (7, 8) is an outer ring fixing sealing component (7) fixed to the inner circumference of the outer ring (2), and the other is an inner ring fixing sealing component (8) fixed to the outer circumference of the inner ring (3). Between the inner circumference of the outer ring fixed sealing member (7) and the outer circumference of the inner ring (3), an oil supply gap (23) is formed to guide lubricating oil supplied from the outside of the bearing into the bearing space (4). An oil drain gap (29) is formed between the outer periphery of the inner ring fixed sealing member (8) and the inner periphery of the outer ring (2) to drain lubricating oil from the bearing space (4).

2. The rolling bearing according to claim 1, characterized in that, The outer ring fixing sealing component (7) has a rubber sealing lip (21), which is provided with a plurality of protrusions (24) spaced apart in the circumferential direction and slidingly contacting the outer periphery of the inner ring (3) via an oil film. The oil supply gap (23) is a gap formed between adjacent protrusions (24) in the circumferential direction.

3. The rolling bearing according to claim 2, characterized in that, A cylindrical sealing sliding contact surface (15) is formed on the outer periphery of the inner ring (3). The sealing sliding contact surface (15) extends axially from the part of the sealing lip (21) that makes sliding contact and is connected to the axial end face (22) of the inner ring (3).

4. The rolling bearing according to claim 3, characterized in that, A cylindrical sealing and fixing surface (16) is formed on the outer periphery of the inner ring (3). The sealing and fixing surface (16) is used for the radial inner end of the inner ring fixing and sealing component (8) to be fitted and fixed. By making the sealing fixing surface (16) and the sealing sliding contact surface (15) symmetrical with the same outer diameter, the shape of the inner ring (3) is symmetrical with respect to the right-angled plane of the axis.

5. The rolling bearing according to any one of claims 1 to 4, characterized in that, A metal shield that does not contact the inner circumference of the outer ring (2) is used as the inner ring fixing and sealing component (8).

6. The rolling bearing according to any one of claims 1 to 5, characterized in that, The inner ring fixing sealing component (8) has: The fitting cylindrical portion (26) fits into the outer periphery of the inner ring (3); The annular plate portion (27) rises radially outward from the fitted cylindrical portion (26); and The edge bend (28) is formed by bending the radially outer end of the annular plate portion (27) towards the axially inner side.

7. The rolling bearing according to claim 6, characterized in that, A circumferential groove (12) is formed on the inner circumference of the outer ring (2), and the circumferential groove (12) extends circumferentially at a position corresponding to the inner ring fixing sealing member (8). At least a portion of the edge bend (28) of the inner ring fixing sealing member (8) is received in the circumferential groove (12).

8. The rolling bearing according to claim 7, characterized in that, A sealing groove (11) is formed on the inner circumference of the outer ring (2), and the sealing groove (11) is used for the radial outer end of the outer ring fixing sealing component (7) to be fitted and fixed. The shape of the outer ring (2) is symmetrical with respect to the right-angled plane of the axis by making the cross-sectional shape of the sealing groove (11) and the cross-sectional shape of the circumferential groove (12) symmetrical.

9. The rolling bearing according to any one of claims 1 to 8, characterized in that, The bearing space (4) is sealed with grease.

10. A rolling bearing, comprising: The inner component (51) has a first track surface (58); The outer component (52) has a second track surface (60); Multiple rolling elements (53) are disposed between the first track surface (58) and the second track surface (60); and A cage (54) holds the plurality of rolling elements (53). The rolling bearing is characterized in that... The rolling bearing also has: The protective member (55) protrudes from the inner diameter surface of the outer member (52) toward the outer diameter surface of the inner member (51) at a position axially away from the rolling element (53) and the cage (54); and The oil slinger (56) protrudes from the outer diameter surface of the inner component (51) toward the inner diameter surface of the outer component (52) at a position away from the rolling element (53) and the cage (54) on the opposite side of the axial direction. The protective element (55) and the inner component (51) form a first oil passage (70). The oil slinger (56) and the outer component (52) form a second oil inlet (71).

11. The rolling bearing according to claim 10, characterized in that, The cage (54) has an annular portion (64) extending circumferentially on the opposite side of the axial direction relative to the plurality of rolling elements (53). The oil-throwing ring (56) has a side plate portion (78) that is axially spaced apart from the side surface (68) on the other side of the annular portion (64).

12. The rolling bearing according to claim 11, characterized in that, The oil-slinging ring (56) has a cylindrical plate portion (77) that is fitted into the inner component (51) in a manner that is radially spaced apart from the annular portion (64). The side plate portion (78) protrudes radially outward from the other side of the axial direction of the cylindrical plate portion (77). The radial distance (g1) between the cylindrical plate portion (77) and the annular portion (64) is set to be smaller than the axial distance (g2) between the side surface (68) on the other side of the axial direction of the annular portion (64) and the side plate portion (78).

13. The rolling bearing according to claim 11 or 12, characterized in that, The radial distance (g3) between the outer periphery of the side plate portion (78) and the outer component (52) is set to be greater than the axial distance (g2) between the side surface (68) on the other side of the annular portion (64) and the side plate portion (78).

14. The rolling bearing according to claim 13, characterized in that, The outer component (52) has: The shoulder (61) is radially spaced from the annular portion (64); and The cutout (63), located radially opposite to the side plate (78), is larger in diameter than the shoulder (61). The outer diameter of the side plate portion (78) is set to be smaller than that of the shoulder portion (61).

15. The rolling bearing according to any one of claims 10 to 14, characterized in that, The inner diameter of the shield (55) is set to be smaller than the inner diameter of the retainer (54).

16. The rolling bearing according to any one of claims 10 to 15, characterized in that, The retainer (54) is positioned further axially away from the shield (55) than the rolling element (53).

17. The rolling bearing according to any one of claims 10 to 16, characterized in that, The protective element (55) has: The front panel (73) is the part closest to the inner component (51) in the shield (55); and The inner diameter side tapered plate portion (74) extends from the axial side of the front end plate portion (73) in a direction inclined to the radially outward.

18. The rolling bearing according to any one of claims 10 to 17, characterized in that, The retainer (54) is made of a resin component having an annular portion (64) extending in a circumferential direction and multiple pairs of claw portions (65, 66) extending axially from the annular portion (64) in such a way as to form a space (67) opening to the radially inward, radially outward and axially to one side. The rolling element (53) is composed of balls disposed in the space (67). The claw portions (65, 66) located between adjacent rolling elements (53) in the circumferential direction are recessed to the opposite side in the axial direction. Let a be the minimum axial thickness from the concave end face (69) of the claw portions (65, 66) located on the opposite axial side to the side surface (68) of the retainer (54) on the opposite axial side. Let b be the axial thickness from the bottom (P) of the bag located on the other side of the axial direction in the space (67) to the side surface (68) on the other side of the axial direction of the retainer (54). When the minimum distance between the imaginary plane passing through the center (O) of the plurality of rolling elements (53) and the concave end face (69) is set as c, The conditions are met: a > b and c > 0.

19. A rotary machine, wherein, have: The rolling bearing (50) as described in any one of claims 10 to 18; The rotating part (101) is supported by the rolling bearing (50); and The oil supply section (102) supplies oil to one side axially relative to the rolling bearing (50).

Images