Bearing device

Abstract

To disclose one example of a specific structure for supplying a lubrication oil to a rolling bearing.SOLUTION: A bearing device 1 includes an oil supply body 20 which cooperates with a bearing ring 11 to form an oil reservoir space 30 which is filled with a lubrication oil. The oil reservoir space 30 is a space which is open on at least the rolling element 12 side. The structure allows a lubrication oil to be supplied from the oil reservoir space 30 to a rolling bearing 10 in the bearing device 1. Thus, compared to oil jet lubrication, the lubrication oil may be stably supplied to the entire rolling bearing 10. Further, the bearing device 1 becomes able to support a rotary shaft, such as a rotor shaft or a gear shaft of an electric motor, which rotates at high speed stably.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a bearing device including a rolling bearing. [Background technology]

[0002] For example, in the bearing device described in Patent Document 1, lubricating oil is supplied to the rolling bearing. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2007-231987 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure discloses an example of a specific configuration for supplying lubricating oil to a rolling bearing. [Means for solving the problem]

[0005] It is desirable for the bearing device to have at least one of the following constituent features, for example: a rolling bearing (10) having an annular raceway (11) and a plurality of rolling elements (12), and an oil supply body (20) arranged on a side surface of the raceway (11) for supplying oil for lubrication to the plurality of rolling elements (12) and a raceway surface of the raceway (11), the oil supply body (20) cooperating with the raceway (11) to form an oil reservoir space (30) filled with oil, the oil reservoir space (30) being a space that is open at least on the side of the rolling elements (12).

[0006] As a result, in the bearing device, oil is supplied from the oil reservoir space (30) to the rolling bearing (10). Therefore, compared to the oil jet lubrication described in Patent Document 1, for example, oil can be supplied to the entire rolling bearing (10) in a more stable manner. Furthermore, with the bearing device, it may be possible to stably support a rotating shaft, such as a motor shaft or gear shaft, that rotates at high speed.

[0007] Incidentally, the symbols in the above parentheses are examples showing the corresponding relationship with the specific configurations etc. described in the embodiments described below, and the present disclosure is not limited to the specific configurations etc. shown by the symbols in the above parentheses. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing a bearing device according to a first embodiment. [Diagram 2] 1 is a diagram showing a structure of a bearing device according to a first embodiment. [Diagram 3] 1 is a partially enlarged view showing the structure of a bearing device according to a first embodiment. [Figure 4] FIG. 2 is a diagram showing an oil supplier according to the first embodiment. [Diagram 5] 6A and 6B are diagrams showing the structure of a bearing device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] The following "embodiment of the invention" shows an example of an embodiment that falls within the technical scope of the present disclosure. In other words, the invention-specific matters described in the claims are not limited to the specific configurations and structures shown in the following embodiment.

[0010] In addition, arrows and diagonal lines indicating directions in each figure are provided to facilitate understanding of the relationship between the figures and the shapes of each member or part. Therefore, the invention shown in this disclosure is not limited to the directions indicated in each figure. Diagonal lines do not necessarily indicate cross-sectional views.

[0011] At least one of each of the members or parts described with a reference number is provided, unless otherwise specified by "one". In other words, unless otherwise specified by "one", two or more of the member may be provided. The bearing device shown in this disclosure includes at least the components such as the members or parts described with a reference number, as well as the structural parts shown in the drawings.

[0012] (First embodiment) <1. Overview of bearing unit> In this embodiment, an example of a bearing device according to the present disclosure is applied to an electric motor used in transportation equipment such as an electric vehicle, etc. Note that the electric vehicle according to the present application refers to a vehicle that can run only by an electric motor, a vehicle that can run using both an electric motor and an internal combustion engine, etc.

[0013] 1, the bearing device 1 includes at least one (two in this embodiment) rolling bearing 10, and at least one oil supplier 20. The two rolling bearings 10 are the same rolling bearing.

[0014] That is, each rolling bearing 10 is configured to have at least an annular raceway 11, a plurality of rolling elements 12, and a cage (not shown), etc. The raceway 11 is a member that constitutes a raceway surface with which the plurality of rolling elements 12 roll and come into contact.

[0015] Each rolling element 12 is a rotating body that rolls and contacts the raceway surface. Each rolling element 12 according to this embodiment is made of a steel ball, and is arranged on a virtual circle centered on the central axis of the raceway ring 11.

[0016] The raceway ring 11 according to this embodiment is composed of an outer ring 11A and an inner ring 11B. The outer ring 11A is disposed radially outward from the rolling elements 12. The inner ring 11B is disposed radially inward from the rolling elements 12. Hereinafter, the outer ring 11A and the inner ring 11B will be collectively referred to as the raceway ring 11.

[0017] The cages are disposed on both sides of the side surface of the raceway 11. That is, two cages are provided for the raceway 11. Each cage holds the position of each rolling element 12 and prevents adjacent rolling elements 12 from contacting each other. The side surface of the raceway 11 refers to a surface facing an imaginary plane perpendicular to the central axis Lo of the raceway 11 (see FIG. 2).

[0018] The oil supplier 20 is a member disposed on the side surface of the raceway 11 for supplying lubricating oil (hereinafter referred to as lubricating oil) to each rolling element 12 and the raceway surface. As shown in Fig. 2, the oil supplier 20 according to this embodiment is disposed between two rolling bearings 10, and also functions as a spacer that determines the position of the rolling bearing 10 in the direction of the central axis Lo.

[0019] <2. Detailed structure of oil supply body> The oil supply body 20 according to this embodiment has a structure that is substantially symmetrical with respect to the center line L1, as shown in Fig. 2. That is, the shape of the oil supply body 20 on the side facing the rolling bearing 10 on the left side of the drawing and the shape of the oil supply body 20 on the side facing the rolling bearing 10 on the right side of the drawing are symmetrical with respect to the center line L1.

[0020] The following description will be given mainly on the shape of the side of the oil supplier 20 that faces the rolling bearing 10 on the right side of the drawing.

[0021] 3, the oil supply body 20 cooperates with the raceway 11 and the rolling elements 12 to form an oil reservoir space 30 (the area shaded with a two-dot chain line). The oil reservoir space 30 is a space filled with lubricating oil, and is open at least on the raceway 11 side, i.e., on the rolling elements 12 side.

[0022] In other words, the space in which the raceways 11 and the rolling elements 12 are arranged is directly or indirectly connected to the oil reservoir space 30. Therefore, the lubricating oil filling the oil reservoir space 30 is supplied to the space in which the raceways 11 and the rolling elements 12 are arranged.

[0023] The oil reservoir space 30 according to this embodiment is configured to include a first oil reservoir space 31 and a second oil reservoir space 32. The first oil reservoir space 31 is an annular space configured between the outer ring 11A and the inner ring 11B, and faces the rolling element 12 and the oil supply body 20.

[0024] The second oil reservoir space 32 is formed by a recess 21 (see FIG. 4) provided in the oil supply body 20. The recess 21 is an annular recess provided on the raceway 11 side of the oil supply body 20 and recessed in the opposite direction to the raceway 11 (see FIG. 3).

[0025] Therefore, the oil reservoir space 30 in this embodiment, i.e., the first oil reservoir space 31 and the second oil reservoir space 32, is an annular space that is open on the rolling body 12 side around the entire circumference, as shown in Figure 3.

[0026] A cage (not shown) is disposed in the first oil reservoir space 31. That is, the oil reservoir space 30 according to this embodiment is indirectly connected to the rolling elements 12 and the raceway surface side via a gap between the cage and the raceway ring 11 in the direction of the center line L1 (see FIG. 3).

[0027] 4, at least one oil inlet portion 22 and one oil outlet portion 23 are provided on the outer circumferential side of the oil supply body 20. The oil inlet portion 22 is a supply port that supplies lubricating oil to the recessed portion 21, i.e., the oil reservoir space 30.

[0028] The oil outlet 23 is an outlet for discharging the lubricating oil in the oil reservoir space 30. The oil inlet 22 or the oil outlet 23 (in this embodiment, the oil outlet 23) is provided with a position maintaining portion 24 for maintaining the position of the oil supplier 20.

[0029] The position maintaining portion 24 is a protruding portion that protrudes radially from the outer circumferential surface of the oil supply body 20. The position maintaining portion 24 is fitted into a recess of a motor housing (not shown), thereby maintaining the position of the oil supply body 20.

[0030] In this embodiment, the lubricating oil discharged from the oil supply body 20 is filtered by a filter (not shown) and then cooled by an oil cooler (not shown). Then, the cooled lubricating oil is supplied to the oil supply body 20 again.

[0031] In this embodiment, the lubricating oil supplied from the oil inlet 22 is drawn into the oil reservoir space 30 by the rotation of the inner ring 11B. Therefore, in this embodiment, the lubricating oil is supplied at a relatively low pressure, and an amount of oil according to the rotation speed can be automatically supplied.

[0032] 3. Features of the Bearing Device According to the Present Embodiment The bearing device 1 of this embodiment is equipped with an oil supply body 20 that cooperates with a raceway ring 11 to form an oil reservoir space 30 filled with lubricating oil, and the oil reservoir space 30 is a space that is open at least on the rolling body 12 side.

[0033] As a result, in the bearing device 1, lubricating oil is supplied from the oil reservoir space 30 to the rolling bearing 10. Therefore, compared to the oil jet lubrication described in Patent Document 1, for example, it may be possible to stably supply lubricating oil to the entire rolling bearing 10. Furthermore, with the bearing device 1, it may be possible to stably support a rotating shaft such as a rotor shaft or gear shaft of an electric motor that rotates at high speed.

[0034] The oil reservoir space 30 according to this embodiment is an annular space that is open all around the circumference toward the rolling elements 12. This makes it possible to more stably supply lubricating oil to the entire rolling bearing 10.

[0035] In the bearing device 1 according to this embodiment, an annular recess 21 recessed in the opposite direction to the raceway 11 is provided on the raceway 11 side of the oil supplier 20, and the recess 21 constitutes at least a part of the oil reservoir space 30. As a result, the amount of lubricating oil filling the oil reservoir space 30 increases compared to a configuration in which the recess 21 is omitted, and the lubricating oil can be supplied to the entire rolling bearing 10 more stably.

[0036] Furthermore, since the heat capacity of the lubricating oil filling the oil reservoir space 30 increases with the amount of lubricating oil filling the oil reservoir space 30, the effect of suppressing seizure of the bearing 10 due to high-speed rotation is higher than in a configuration without the recessed portion 21. Therefore, the bearing device 1 can support a wide range of rotational speeds.

[0037] Second embodiment The oil reservoir space 30 according to the above-described embodiment is constituted by the first oil reservoir space 31 and the second oil reservoir space 32. In contrast, in the bearing device 1 according to the present embodiment, the second oil reservoir space 32 is eliminated, and the oil reservoir space 30 is constituted by only the first oil reservoir space 31.

[0038] For this reason, the oil supply body 20 according to this embodiment is not provided with the recessed portion 21. Note that the same components as those in the above-described embodiment are denoted by the same reference numerals as those in the above-described embodiment. For this reason, in this embodiment, duplicated explanations are omitted.

[0039] (Other embodiments) In the rolling bearing 10 according to the embodiment described above, the raceway ring 11 is formed of the outer ring 11A and the inner ring 11B. However, the present disclosure is not limited to this. That is, the present disclosure may be such that, for example, either one of the outer ring 11A or the inner ring 11B is eliminated, and the eliminated ring is formed by utilizing a motor housing or the like.

[0040] The rolling bearing 10 according to the embodiment described above is an angular contact ball bearing. However, the present disclosure is not limited to this. That is, the rolling bearing according to the present disclosure may be, for example, a radial ball bearing, a radial roller bearing, a tapered roller bearing, or the like.

[0041] The oil reservoir space 30 according to the embodiment described above is an annular space and is open on the rolling element 12 side over the entire circumference. However, the present disclosure is not limited to this. That is, the present disclosure may be, for example, an annular space having an arc-shaped opening only partially open toward the rolling element 12 side.

[0042] The oil supply body 20 according to the above embodiment also serves as a spacer. However, the present disclosure is not limited to this. That is, the present disclosure may also be such that, for example, a part of a motor housing also serves as the oil supply body 20.

[0043] In the above-described embodiment, there are two rolling bearings 10. However, the present disclosure is not limited to this. That is, the present disclosure may be, for example, only one of the two rolling bearings 10.

[0044] In the above-described embodiment, two cages are provided on the raceway shaft 11. However, the present disclosure is not limited to this. That is, the present disclosure may also be applicable to a case where, for example, one cage is provided. Even when one cage is provided on the raceway shaft 11, the same effects as those of the above-described embodiment can be obtained.

[0045] The oil supply body 20 according to the above embodiment has a structure that is substantially symmetrical with respect to the center line L1. However, the present disclosure is not limited to this. That is, the present disclosure may have a structure that is asymmetrical with respect to the center line L1, for example.

[0046] The rolling elements 12 in the above-described embodiment are steel balls. However, the present disclosure is not limited thereto. That is, the present disclosure may be, for example, a configuration in which the rolling elements 12 are made of the same material as the raceway 11, or a configuration in which the rolling elements 12 are made of a different material than the raceway 11.

[0047] Furthermore, the present disclosure is not limited to the above-mentioned embodiments as long as it is consistent with the gist of the disclosure described in the above-mentioned embodiments. Therefore, the present disclosure may be a configuration in which at least two of the above-mentioned embodiments are combined, or a configuration in which any of the components illustrated or the components described with reference numerals in the above-mentioned embodiments are eliminated. [Explanation of symbols]

[0048] 1... Bearing device 10... Bearing 11... Bearing ring 11A... outer ring 11B... inner ring 12... rolling element 20: Oil supply body 21: Recessed portion 30... Oil reservoir space 31... First oil reservoir space 32… Second oil reservoir space

Claims

1. A rolling bearing having an annular raceway and a plurality of rolling elements; an oil supply body arranged on a side surface of the raceway ring for supplying oil for lubrication to the rolling elements and a raceway surface of the raceway ring, the oil supply body cooperating with the raceway ring to define an oil reservoir space filled with the oil; a position maintaining portion for maintaining the position of the oil supply body, At least one oil inlet for supplying the oil to the oil reservoir space and at least one oil outlet for discharging the oil in the oil reservoir space are provided on an outer circumferential side of the oil supply body, the oil supply body is a spacer that determines a position of the rolling bearing in a central axial direction, the oil reservoir space is an annular space that is open at least on the rolling element side, and the rolling element side is open over the entire circumference, Furthermore, the bearing device wherein the attitude maintaining portion is provided at the oil inlet portion or the oil outlet portion.

2. The oil supply body has an annular recess on the raceway side, the recess forming at least a part of the oil reservoir space and facing away from the raceway, The oil supply body is configured in an annular shape, and an inner diameter dimension of the oil supply body is larger than an inner diameter dimension of the rolling bearing, The bearing device according to claim 1 , wherein the recess further communicates with an inner peripheral space of the oil supply body.

3. The raceway includes an outer ring disposed radially outward relative to the plurality of rolling elements and an inner ring disposed radially inward relative to the plurality of rolling elements, 3. The bearing device according to claim 2, wherein an inner diameter of the oil supply body is larger than an outer diameter of the inner ring.

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