Rolling bearing device

Abstract

This suppresses the increase in stirring resistance in rolling bearing devices. [Solution] A rolling bearing device 10 comprising: an inner ring member 11 having an inner ring raceway 11b formed on its outer circumferential surface 11a; an outer ring member 12 having an outer ring raceway 12b formed on its inner circumferential surface 12a; a plurality of rolling elements 13 provided between the inner ring raceway 11b and the outer ring raceway 12b; and a penetrating member 16 fixed to the inner circumferential surface 12a of the outer ring member 12, through which a lubricant is permeated; wherein a storage space 40 is formed on the inner circumferential surface 12a of the outer ring member 12 on the axial side opposite the outer ring raceway 12b, with the penetrating member 16 in between, for storing the lubricant flowing out from the penetrating member 16.

Description

Technical Field

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

Background Art

[0002] In order to maintain the lubrication of a rolling bearing device over a long period, a member impregnated with a lubricant may be provided inside the rolling bearing device. For example, Patent Document 1 discloses a rolling bearing device in which an impregnation member through which a lubricant penetrates is installed in a lubricant storage member (outer ring spacer) having a storage chamber for storing a lubricant inside. The impregnation member is composed of a porous body, and the storage chamber is filled with a lubricant such as grease or lubricating oil. Then, after the lubricant penetrates the impregnation member, it flows out from an opening provided in the storage chamber to lubricate the rolling elements and each raceway surface.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The viscosity of the lubricant tends to decrease as the temperature rises. Therefore, in the technology of Patent Document 1, when the internal temperature of the rolling bearing device rises, the lubricant impregnated in the impregnation member flows out excessively to the rolling elements and each raceway surface, resulting in an increase in the stirring resistance of the rolling bearing device.

[0005] In view of such problems, an object of the present disclosure is to suppress an increase in the stirring resistance of a rolling bearing device.

Means for Solving the Problems

[0006] The rolling bearing device of the present disclosure comprises an inner ring member having an inner ring raceway formed on its outer circumference, an outer ring member having an outer ring raceway formed on its inner circumference, a plurality of rolling elements provided between the inner ring raceway and the outer ring raceway, and a penetrating member fixed to the inner circumference of the outer ring member and into which a lubricant is permeated, wherein a storage space is formed on the inner circumference of the outer ring member on the axial side opposite the outer ring raceway with respect to the penetrating member, for storing the lubricant flowing out from the penetrating member. [Effects of the Invention]

[0007] According to this disclosure, it is possible to suppress the increase in stirring resistance of a rolling bearing device. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a cross-sectional view of a rolling bearing device according to an embodiment. [Figure 2] Figure 2 is a magnified view of a portion of the rolling bearing device shown in Figure 1. [Figure 3] Figure 3 is a schematic diagram illustrating the storage space according to the embodiment. [Figure 4] Figure 4 is a graph illustrating an example of the temperature dependence of the lubricant retention rate of a penetrating material. [Figure 5] Figure 5 is a schematic diagram illustrating a modified storage space. [Figure 6] Figure 6 is a partially enlarged view of a rolling bearing device according to a modified example. [Figure 7] Figure 7 is a partially enlarged view of a rolling bearing device according to a modified example. [Figure 8] Figure 8 is a schematic diagram showing an example of a permeable member manufactured using a laminated structure. [Figure 9] Figure 9 is a schematic diagram of the permeable member shown in Figure 8, viewed from the axial direction. [Modes for carrying out the invention]

[0009] <Summary of the embodiments of this disclosure> The embodiments of this disclosure are outlined below.

[0010] (1) The rolling bearing device of the present disclosure comprises an inner ring member having an inner ring raceway formed on its outer circumference, an outer ring member having an outer ring raceway formed on its inner circumference, a plurality of rolling elements provided between the inner ring raceway and the outer ring raceway, and a penetrating member fixed to the inner circumference of the outer ring member and into which a lubricant is permeated, wherein a storage space is formed on the inner circumference of the outer ring member on the axial side opposite the outer ring raceway with respect to the penetrating member, for storing the lubricant flowing out from the penetrating member.

[0011] By providing a storage space to store lubricant flowing out from the permeable member, it is possible to suppress the supply of excess lubricant to the outer ring raceway. Furthermore, the storage space is formed on the axial opposite side of the permeable member from the outer ring raceway. Therefore, in order for the lubricant flowing out from the permeable member and stored in the storage space to reach the outer ring raceway, it must permeate the permeable member again and pass through it. In other words, the lubricant stored in the storage space remains in the storage space because the permeable member acts as a barrier, and is not immediately supplied to the outer ring raceway. As a result, it is possible to suppress the supply of excess lubricant to the outer ring raceway, thereby suppressing the increase in agitation resistance of the rolling bearing device.

[0012] (2) In the rolling bearing device described in (1) above, the axial direction of the rolling bearing device is a direction that includes a horizontal component, a shoulder is formed on the inner circumferential surface of the outer ring member adjacent to one side of the outer ring raceway in the axial direction, the storage space is formed on one side of the shoulder in the axial direction, and at least a portion of the storage space may be located below the shoulder in the direction of gravity.

[0013] The lubricant flowing out from the impregnation member flows downward in the direction of gravity. Since at least a part of the storage space is located below the shoulder leading to the outer ring raceway in the direction of gravity, most of the lubricant flowing out from the impregnation member flows to this region rather than the shoulder and is stored in the storage space. As a result, excessive lubricant can be prevented from being supplied to the outer ring raceway, and an increase in the stirring resistance of the rolling bearing device can be suppressed.

[0014] (3) In the rolling bearing device of (2) above, the volume of the region of the storage space located below the shoulder in the direction of gravity may be 5% or more and 10% or less of the volume of the impregnation member.

[0015] With such a configuration, since most of the lubricant flowing out from the impregnation member when the temperature of the impregnation member rises can be stored in this region, it is possible to suppress the supply of excessive lubricant that has flowed out to the outer ring raceway, and at the same time, the volume required to secure the storage space can be kept small, and it is possible to suppress the enlargement of the rolling bearing device due to securing the storage space.

[0016] (4) In the rolling bearing device of (1) above, a shoulder is formed on the inner peripheral surface of the outer ring member adjacent to one axial side of the outer ring raceway, and a counterbore is formed adjacent to the other axial side of the outer ring raceway. The storage space is formed on the other axial side of the counterbore, and at least a part of the storage space may be located below the counterbore in the direction of gravity.

[0017] With such a configuration, when the lubricant flows out from the impregnation member, the lubricant preferentially flows out to the region located below in the direction of gravity, and it is possible to suppress the supply of excessive lubricant to the outer ring raceway. As a result, an increase in the stirring resistance of the rolling bearing device can be suppressed.

[0018] (5) In the rolling bearing device according to (1) to (4) above, a region of the inner peripheral surface of the outer ring member where the storage space is formed may include an inclined surface that slopes radially outward as it approaches the penetration member in the axial direction.

[0019] By configuring it in this way, the lubricant stored in the storage space can be guided to the penetration member. Thereby, the "return" of the lubricant to the penetration member is promoted, and a state where an appropriate amount of lubricant penetrates into the penetration member can be maintained for a longer period.

[0020] <Details of Embodiments of the Present Disclosure> Hereinafter, details of embodiments of the present disclosure will be described with reference to the drawings. Note that at least a part of the embodiments described below may be arbitrarily combined.

[0021] 〔Overall Configuration of Ball Bearing〕 FIG. 1 is a cross-sectional view of a rolling bearing device 10 according to an embodiment. The rolling bearing device 10 illustrated in FIG. 1 is a rolling bearing device that rotatably holds a shaft S1 while being fixed to a housing H1. The use of the rolling bearing device 10 is not particularly limited, but for example, it may be used for supporting the main shaft of a machine tool such as a machining center or a NC lathe, or it may be used in a vehicle or the like.

[0022] The rolling bearing device 10 includes an inner ring member 11, an outer ring member 12, a plurality of rolling elements 13, a cage 14, a seal member 15, and a penetration member 16. The inner ring member 11, the outer ring member 12, and the plurality of rolling elements 13 are each formed of a metal material such as high-carbon chromium bearing steel. The rolling bearing device 10 is an inner ring rotation type bearing in which the inner ring member 11 serves as a rotating ring and the outer ring member 12 serves as a fixed ring.

[0023] In this disclosure, the direction along the center line C1 of the rolling bearing device 10 is the axial direction of the rolling bearing device 10, and is simply referred to as the "axial direction." The axial direction also includes the direction parallel to the center line C1 (the left and right directions in Figure 1). The left side of Figure 1 is defined as "one side" of the axial direction, and the right side of Figure 1 is defined as "the other side" of the axial direction. The direction perpendicular to the center line C1 is the radial direction of the rolling bearing device 10, and is simply referred to as the "radial direction." The direction in which the rolling bearing device 10 (specifically, the inner ring member 11) rotates around the center line C1 is the circumferential direction of the rolling bearing device 10, and is simply referred to as the "circumferential direction."

[0024] The rolling bearing device 10 illustrated in Figure 1 is an angular contact ball bearing. However, the type of rolling bearing device 10 is not limited to an angular contact ball bearing; for example, it may be a deep groove ball bearing (ball bearing). Furthermore, although the rolling bearing device 10 is shown as a single-row rolling bearing device with one rolling element 13 in the axial direction, the rolling bearing device 10 may also be a double-row rolling bearing with two or more rolling elements 13 spaced apart from each other in the axial direction.

[0025] The axial direction of the rolling bearing device 10 includes a horizontal component. More specifically, as illustrated in Figure 1, the shaft S1 extends along the horizontal direction, and the rolling bearing device 10 is fixed to the housing H1 with its radial direction oriented in the direction of gravity. In this case, the lower side of Figure 1 is the lower side in the direction of gravity. Note that the shaft S1 does not need to be perfectly aligned horizontally; it may be tilted within a range of, for example, ±45 degrees relative to the horizontal direction. As a result, the radial direction of the rolling bearing 10 includes a component in the direction of gravity.

[0026] Figure 2 is a magnified view of a portion of the rolling bearing device 10 shown in Figure 1. Figure 2 shows a magnified view of the portion of the rolling bearing device 10 in Figure 1 that is located below the axis S1 in the direction of gravity.

[0027] The inner ring member 11 is an annular member that is fitted and fixed to the shaft S1. The inner ring member 11 includes an inner ring 31 and an inner ring spacer 32 provided adjacent to one side of the inner ring 31 in the axial direction. The shaft S1 is, for example, the spindle of a machine tool. The outer circumferential surface 11a of the inner ring member 11 includes an arc-shaped inner ring raceway (raceway groove) 11b on which the rolling elements 13 roll. The inner ring raceway 11b is formed on the outer circumferential surface of the inner ring 31.

[0028] The outer ring member 12 is a member that is fitted and fixed inside the housing H1. The outer ring member 12 includes an outer ring 21 and an outer ring spacer 22 provided adjacent to one axial side of the outer ring 21. The inner circumferential surface 12a of the outer ring member 12 includes an outer ring raceway 12b, a shoulder portion 12c, a counterbore 12d, a fitting surface 12e, and a storage surface 12f.

[0029] Here, the outer ring raceway 12b, shoulder portion 12c, and counterbore 12d are formed on the inner circumferential surface of the outer ring 21. The mating surface 12e is formed spanning the end portion 21a of the inner circumferential surface on one axial side of the outer ring 21 and the end portion 22a of the inner circumferential surface on the other axial side of the outer ring spacer 22. The storage surface 12f is formed in a portion of the inner circumferential surface 22b of the outer ring spacer 22.

[0030] The outer ring raceway 12b is a substantially arc-shaped raceway groove on which the rolling elements 13 roll. A shoulder portion 12c is formed on one axial side of the outer ring raceway 12b. In contrast, a counterbore 12d (counter-bored) is formed on the other axial side of the outer ring raceway 12b, where the shoulder portion has been removed to create a flat surface. Therefore, the inner diameter of the counterbore 12d is larger than the inner diameter of the shoulder portion 12c.

[0031] The shoulder portion 12c is a flat surface formed on one axial side of the outer ring raceway 12b. The shoulder portion 12c also functions as a guide surface that guides the cage 14 by contacting the outer circumferential surface of the cage 14, which vibrates radially.

[0032] When the cage 14 is positioned on the design track, the outer surface of the cage 14 faces the shoulder portion 12c with a radial gap between them. During the rotational operation of the rolling bearing device 10, the cage 14 rotates while vibrating radially, and if the amount of vibration exceeds the gap, the outer surface of the cage 14 comes into contact with the shoulder portion 12c, restricting the radial vibration of the cage 14. In this way, the rolling bearing device 10 is an outer ring guided type rolling bearing device in which the cage 14 is guided by the outer ring member 12.

[0033] The mating surface 12e is a flat surface provided adjacent to one axial side of the shoulder portion 12c and is recessed radially outward from the shoulder portion 12c. Therefore, the inner diameter of the mating surface 12e is larger than the inner diameter of the shoulder portion 12c. The penetrating member 16 is fitted into the mating surface 12e.

[0034] Multiple rolling elements 13 are arranged circumferentially between the inner ring raceway 11b and the outer ring raceway 12b. When the inner ring member 11 rotates circumferentially with the shaft S1, the multiple rolling elements 13 roll between these two raceways 11b and 12b. The multiple rolling elements 13 also contact the two raceways 11b and 12b at a predetermined contact angle and receive both axial and radial loads applied from the shaft S1 and the like.

[0035] The retainer 14 is an annular member that holds a plurality of rolling elements 13 at predetermined intervals in the circumferential direction. In the example in Figure 1, the retainer 14 is a cantilevered retainer that holds a plurality of rolling elements 13 from both sides in the axial direction. The type of retainer 14 is not particularly limited, and it may be a cantilevered retainer that holds a plurality of rolling elements 13 from one side (one side or the other side) in the axial direction. The retainer 14 is manufactured, for example, by injection molding of a synthetic resin material such as polyamide resin or polyetheretherketone (PEEK).

[0036] The sealing member 15 is an annular member that seals the annular space between the inner ring member 11 and the outer ring member 12. The sealing member 15 is fitted and fixed to one axial end of the outer ring spacer 22, and forms a labyrinth gap between it and the uneven shape 32a provided on one axial end of the inner ring spacer 32. In this way, the sealing member 15 seals the space between the inner ring member 11 and the outer ring member 12, preventing foreign matter from entering the annular space from outside the rolling bearing device 10, and preventing lubricant and the like from leaking out of the annular space to the outside of the rolling bearing device 10.

[0037] The penetrating member 16 is a member into which a lubricant has been impregnated. The penetrating member 16 includes, for example, a porous body having a large number of continuous pores, and the lubricant is impregnated by accumulating the lubricant in the pores of the porous body. The porous body of the penetrating member 16 is, for example, a resin sintered body such as sintered polyethylene.

[0038] The lubricant may be a lubricating oil or a grease. In the case of a lubricating oil, the oil penetrates directly into the penetrating member 16. In the case of a grease, the grease is applied to the outside of the penetrating member 16, and the base oil that seeps out from the grease penetrates into the penetrating member 16.

[0039] The permeable member 16 is internally fitted and fixed to the mating surface 12e. The permeable member 16 includes a first portion 16a located radially outward from the shoulder portion 12c and a second portion 16b located radially inward from the shoulder portion 12c. The second portion 16b further includes a third portion 16c that protrudes axially to the other side (shoulder portion 12c side) from the mating surface 12e. The third portion 16c is located, for example, axially to one side of the inner ring raceway 11b and the outer ring raceway 12b, and is situated between the outer circumferential surface 11a of the inner ring member 11 and the retainer 14.

[0040] The first part 16a and the second part 16b are formed as a single unit, and the lubricant permeating the penetrating member 16 permeates both the first part 16a and the second part 16b. The lubricant gradually flows out, for example, from the third part 16c, along at least one of the outer circumferential surface of the inner ring 31, the retainer 14, and the shoulder portion 12c, and is supplied to the inner ring raceway 11b or the outer ring raceway 12b. As the shaft S1 and the inner ring member 11 rotate, the multiple rolling elements 13 roll, and the lubricant supplied to the inner ring raceway 11b or the outer ring raceway 12b is supplied to the rolling elements 13 and the other side of the inner ring raceway 11b or the outer ring raceway 12b. As a result, the inner ring raceway 11b, the outer ring raceway 12b, and the multiple rolling elements 13 are lubricated, respectively.

[0041] As the lubricant flows out from the third section 16c, the lubricant impregnated in the penetrating member 16 moves from the first section 16a to the second section 16b by capillary action or the like. By appropriately designing the viscosity of the lubricant and the shape of the penetrating member 16 (for example, the pore density, pore arrangement, and pore radius of the porous body), the outflow rate of the lubricant from the third section 16c can be adjusted. By adjusting this outflow rate to the minimum speed suitable for lubricating the rolling bearing device 10, the lubricant can be released from the penetrating member 16 over a long period of time, and the lubrication of the rolling bearing device 10 can be maintained for a longer period of time.

[0042] Here, the viscosity of the lubricant tends to decrease as the temperature increases. Therefore, as the internal temperature of the rolling bearing device 10 rises, a larger amount of lubricant may flow out from the penetrating member 16. When the excess lubricant that has flowed out is supplied to the inner ring raceway 11b and the outer ring raceway 12b, the stirring resistance of the lubricant in each raceway 11b and 12b of the rolling bearing device 10 increases, and the energy loss in the rolling bearing device 10 increases. Since the internal temperature of the rolling bearing device 10 tends to rise with high-speed rotation or prolonged rotation, this problem becomes particularly pronounced in the rolling bearing device 10 used for a long time under high-speed rotation.

[0043] To solve this problem, a storage space 40 is formed on the inner circumferential surface 12a of the outer ring member 12 to store lubricant flowing out from the permeation member 16. When the temperature of the rolling bearing device 10 rises and an excessive amount of lubricant flows out from the permeation member 16, the flowing lubricant is stored in this storage space 40, thereby preventing the excess lubricant from being supplied to the outer ring raceway 12b. As a result, the increase in the stirring resistance of the rolling bearing device 10 can be suppressed.

[0044] The storage space 40 is a space enclosed by the storage surface 12f, the side surface 12g, the sealing member 15, and the permeable member 16. The storage surface 12f is a flat surface provided adjacent to one axial side of the fitting surface 12e on the inner circumferential surface 12a of the outer ring member 12, and is excavated radially outward from the shoulder portion 12c.

[0045] As shown in Figure 2, the inner diameter of the storage surface 12f is smaller than the inner diameter of the fitting surface 12e. As a result, a step is formed between the storage surface 12f and the fitting surface 12e, so that the permeation member 16 gets caught on this step and is prevented from moving axially toward the storage surface 12f.

[0046] The inner diameters of the storage surface 12f and the fitting surface 12e may be the same. That is, the storage surface 12f and the fitting surface 12e may be formed flush in the axial direction. By configuring it in this way, the lubricant flowing out from the permeable member 16 can be smoothly guided to the storage surface 12f.

[0047] The side surface 12g is a surface that extends radially inward from one axial side of the storage surface 12f. The side surface 12g is, for example, a region 22c that extends radially inward from one axial side of region 22b of the outer ring spacer 22. The storage surface 12f and the side surface 12g are each provided in an annular shape over the circumferential direction. In Figure 2, the storage space 40 is formed as an annular, substantially closed space with the storage surface 12f as the bottom surface, the side surface 12g and the sealing member 15 as the side surface on one axial side, and the permeation member 16 as the side surface on the other axial side and the top surface.

[0048] In the initial state, that is, when the rolling bearing device 10 is unused and placed in a room temperature environment, and when excessive lubricant has not leaked out from the impregnated member 16, the storage space 40 is empty and contains no lubricant. However, even at room temperature, a small amount of lubricant seeps out from the impregnated member 16, so the storage space 40 is not completely devoid of lubricant. Nevertheless, in the initial state, the majority of the volume of the storage space 40 is empty and not filled with lubricant.

[0049] The storage space 40 is formed on one axial side of the permeation member 16 (i.e., on the opposite side in the axial direction from the shoulder portion 12c and the outer ring track 12b). Furthermore, at least a portion of the storage space 40, region 40a (Figure 3), is located below the shoulder portion 12c in the direction of gravity.

[0050] Figure 3 is a schematic diagram illustrating the storage space 40. Figure 3 is a cross-sectional view taken by cutting the rolling bearing device 10 along the cutting line III-III in Figure 1, and only the outer ring member 12 is shown to explain the positional relationship of the storage space 40 with respect to the shoulder portion 12c.

[0051] The storage space 40 is formed circumferentially, as shown in Figure 3. The region of the storage space 40 located below the shoulder portion 12c in the direction of gravity is called "region 40a". More specifically, in Figure 3, the reference line L1 indicates the lowest height in the direction of gravity of the shoulder portion 12c, and the region of the storage space 40 located below the reference line L1 in the direction of gravity is called "region 40a".

[0052] The storage space 40 includes a region 40a located below the shoulder portion 12c in the direction of gravity. When the lubricant becomes hot and its viscosity decreases, it flows out from the penetrating member 16 (particularly the first portion 16a on the lower side in the direction of gravity) and flows downward in the direction of gravity. As described above, since the storage space 40 is an "empty" space that is not filled with lubricant in its initial state, it can store the lubricant that has flowed out from the penetrating member 16.

[0053] In particular, since region 40a is located below the shoulder portion 12c leading to the outer ring raceway 12b in the direction of gravity, most of the lubricant flowing out from the permeating member 16 flows to region 40a rather than the shoulder portion 12c and is stored in the storage space 40. This prevents excessive lubricant from being supplied to the outer ring raceway 12b, thereby suppressing an increase in the stirring resistance of the rolling bearing device 10.

[0054] Furthermore, the storage space 40 is formed on the opposite side of the outer ring raceway 12b in the axial direction from the permeation member 16. Therefore, in order for the lubricant that flows out from the permeation member 16 and is stored in the storage space 40 to reach the outer ring raceway 12b, it must permeate the permeation member 16 again and pass through the permeation member 16. In other words, the lubricant stored in the storage space 40 remains in the storage space 40 because the permeation member 16 acts as a barrier, and is not immediately supplied to the outer ring raceway 12b. This suppresses the supply of excessive lubricant to the outer ring raceway 12b, and thus suppresses the increase in the stirring resistance of the rolling bearing device 10.

[0055] Figure 4 is a graph illustrating an example of the temperature dependence of the lubricant retention rate of the penetrating member 16. The horizontal axis of Figure 4 shows the temperature [°C] of the penetrating member 16, and the vertical axis shows the lubricant retention rate [volume %] of the penetrating member 16. The graph in Figure 4 shows the results of a test conducted to investigate the lubricant retention rate using an annular porous resin with an outer diameter of 100 [mm], an inner diameter of 90 [mm], and an axial width of 20 [mm] as the penetrating member 16.

[0056] For example, at 25°C, 66% by volume of lubricant can penetrate the penetrating member 16. In contrast, at 60°C, only 60% by volume of lubricant can penetrate the penetrating member 16. That is, if the penetrating member 16, which has been impregnated with 66% by volume of lubricant at 25°C, is heated to 60°C, approximately 6% by volume of lubricant will flow out of the penetrating member 16.

[0057] While these specific values ​​vary depending on the type of lubricant and the shape of the porous resin (e.g., pore density, pore arrangement, and pore radius), the graph in Figure 4 generally shows that the higher the temperature of the penetrating member 16, the lower the lubricant retention rate in the penetrating member 16 tends to be.

[0058] Therefore, the volume of the region 40a located below the shoulder portion 12c in the direction of gravity within the storage space 40 is set to, for example, 5% to 10% of the volume of the permeation member 16. By setting it to 5% or more, most of the lubricant that flows out from the permeation member 16 when the temperature of the permeation member 16 rises (in Figure 4, when 6 [volume %] of the lubricant flows out, 80% or more of the flow volume) can be stored in region 40a, thereby suppressing the supply of excess lubricant that has flowed out to the outer ring raceway 12b.

[0059] Furthermore, by keeping it below 10%, the volume required to be secured as storage space 40 can be kept small, and the rolling bearing device 10 can be prevented from becoming larger in order to secure storage space 40.

[0060] [Variation] The following describes modified examples of the embodiments. In the following modified examples, components identical to those in the embodiments are denoted by the same reference numerals and their descriptions are omitted.

[0061] [Modification 1: The storage space 40 is formed only in a portion of the circumferential direction.] Figure 5 is a schematic diagram illustrating a modified example of the storage space 40. In the above embodiment (Figure 4, etc.), the storage space 40 is formed in an annular shape over the circumferential direction. However, the storage space 40 only needs to have the function of storing lubricant flowing out from the permeable member 16, and since the flowing lubricant tends to flow downward in the direction of gravity from the permeable member 16, the storage space 40 may be provided only on the side below the center line C1 in the direction of gravity, for example. In this case, the storage space 40 does not need to be formed uniformly over the circumferential direction, and may be formed in an asymmetrical state (rotationally asymmetric) relative to the center line C1.

[0062] Figure 5 shows an example in which the inner circumferential surface of the outer ring spacer 22 is partially excavated below the reference line L1 in the direction of gravity, thereby forming a region 22b where the storage surface 12f is located only in a part of the circumferential direction. In this case, since most of the storage space 40 is the region 40a located below the shoulder portion 12c in the direction of gravity, the storage space 40 can be reduced in size while maintaining the storage function of the storage space 40. This allows for an increase in the volume of, for example, the permeable member 16, and enables more effective use of the annular space within the rolling bearing device 10.

[0063] [Modification 2: The storage space 40 is formed on the counterbore 12d side.] Figure 6 is a partially enlarged view of a modified rolling bearing device 10a. In the rolling bearing device 10 (Figure 2, etc.), the storage space 40 is formed on one axial side of the shoulder portion 12c. However, the position in which the storage space 40 is formed is not limited to this, and it may also be formed on the other axial side of the counterbore 12d.

[0064] The following mainly describes the differences from the embodiment of the rolling bearing device 10a. The rolling bearing device 10a includes an outer ring member 120 instead of an outer ring member 12, and a permeable member 160 instead of a permeable member 16. The outer ring member 120 includes an outer ring 210 and an outer ring spacer 220 provided adjacent to the other axial side of the outer ring 210.

[0065] The inner circumferential surface of the outer ring spacer 220 includes a region 220a adjacent to the outer ring 210 in the axial direction, in which the permeable member 160 is fitted and fixed, and a region 220b on the other axial side of region 220a that forms the bottom surface of the storage space 400.

[0066] The penetrating member 160 is fitted and fixed inside the counterbore 12d, spanning both the axially opposite region and region 220a. The lubricant that flows out from the penetrating member 160 to the axially opposite side is supplied to the outer ring raceway 12b via the counterbore 12d. This lubricates the rolling bearing device 10a.

[0067] The storage space 400 is a space for storing lubricant that flows out from the permeation member 160 to the other axial side. The storage space 400 is an annular space with region 220b as the bottom surface, the permeation member 160 as one axial side surface, and a part of the outer ring spacer 220 as the other axial side surface.

[0068] The inner diameter of region 220b is larger than the inner diameter of the counterbore 12d, and at least a portion of the storage space 400 is located below the counterbore 12d in the direction of gravity. Therefore, when the temperature of the rolling bearing device 10a rises and lubricant flows out from the permeating member 160, the lubricant preferentially flows out to the region located below in the direction of gravity, preventing an excess of lubricant from being supplied to the outer ring raceway 12b. As a result, an increase in the stirring resistance of the rolling bearing device 10 can be suppressed.

[0069] Furthermore, regions 220a and 220b are flush in the axial direction and have the same inner diameter. Therefore, the lubricant flowing out from the permeation member 160 to the other axial direction flows smoothly along the inner circumferential surface of the outer ring spacer 220 into region 220b, allowing for optimal guidance of the lubricant into the storage space 400. As a result, it is possible to suppress the supply of excessive lubricant to the outer ring raceway 12b, thereby suppressing an increase in the stirring resistance of the rolling bearing device 10.

[0070] [Modification 3: Inclined surface 22c] Figure 7 is a partially enlarged view of a modified rolling bearing device 10b. In the rolling bearing device 10 (Figure 2, etc.), the bottom surface of the storage space 40 is formed by a flat storage surface 12f. However, as shown in Figure 7, the bottom surface of the storage space 40 may also include an inclined surface 12h.

[0071] The following mainly describes the differences from the embodiment of the rolling bearing device 10b. The rolling bearing device 10b includes an outer ring member 121 instead of the outer ring member 12. The outer ring member 121 includes an outer ring 21 and an outer ring spacer 221 provided adjacent to the other axial side of the outer ring 21. In this modified example, the main difference from the rolling bearing device 10 according to the embodiment is that, instead of the shapes of regions 22b and 22c, the shape of the inner circumferential surface of the outer ring spacer 221 is an inclined surface 22d (inclined surface 12h) that slopes radially outward as it approaches the permeable member 16. The other axial side of the inclined surface 22d is connected to the end 22a.

[0072] As the viscosity decreases due to the rise in temperature, the lubricant that flows out of the permeating member 16 and is stored in the storage space 40 moves from the storage space 40 to the permeating member 16 by permeating it again as the temperature of the permeating member 16 decreases. At this time, the inclined surface 12h that forms the bottom surface (the surface on the downward side in the direction of gravity) of the storage space 40 is tilted toward the permeating member 16, which allows the lubricant stored in the storage space 40 to be guided toward the permeating member 16. This promotes the "return" of the lubricant to the permeating member 16, and allows the state in which an appropriate amount of lubricant is permeated into the permeating member 16 to be maintained for a longer period of time.

[0073] [Modification 4: Method for manufacturing the permeable member 16] Figure 8 is a schematic diagram showing an example of a permeable member 16 manufactured using a laminated structure. Figure 9 is a schematic diagram of the permeable member 16 shown in Figure 8, viewed from the axial direction.

[0074] In the above embodiment, the first portion 16a and the second portion 16b of the permeable member 16 are formed as a single unit. However, the present disclosure is not limited thereto, and the permeable member 16 may be manufactured by combining a plurality of radially divided parts.

[0075] In the example shown in Figure 8, the permeable member 16 is divided radially into three parts: a first part 161, a second part 162, and a third part 163. The permeable member 16 may be manufactured by stacking these parts radially. In this case, the parts 161, 162, and 163 are not joined together with adhesive or the like, but are simply stacked radially. Each part 161, 162, and 163 is, for example, a polyvinyl alcohol-based sponge.

[0076] For example, as shown in Figure 9, strip-shaped members are rolled into a C-shape to produce each of the parts 161, 162, and 163. Then, these parts 161, 162, and 163 are stacked radially to form a single permeable member 16. By manufacturing in this multilayer structure, it is possible to manufacture permeable members 16 of a variety of shapes more easily than when they are formed as a single unit as in the embodiment.

[0077] [Note] The embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of this disclosure is not limited to the embodiments and variations described above, but includes all modifications within the scope of equivalence to the configurations described in the claims. [Explanation of Symbols]

[0078] 10, 10a, 10b Rolling bearing device 11 Inner ring member 11a Outer surface 11b Inner ring raceway 12,120,121 Outer ring member 12a Inner circumferential surface 12b Outer ring raceway 12c Shoulder section 12d Counterbore 12e Mating surface 12f Storage surface 12g Side 12h Inclined surface 13 Rolling element 14 Cage 15 sealing member 16,160 permeable member 16a first part 16b Part 2 16c Part 3 161 Part 1 162 Part 2 163 Part 3 21,210 Outer ring 22,220,221 Outer wheel spacer 31 Inner wheel 32 Inner wheel space 40,400 Storage space H1 Housing S1 axis C1 center line L1 reference line

Claims

1. An inner ring member having an inner ring raceway formed on its outer surface, An outer ring member having an outer ring raceway formed on its inner circumferential surface, A plurality of rolling elements are provided between the inner ring raceway and the outer ring raceway, A penetrating member fixed to the inner circumferential surface of the outer ring member, into which a lubricant is permeated, Equipped with, On the inner circumferential surface of the outer ring member, a storage space is formed on the axial side of the outer ring raceway, with the permeation member in between, for storing the lubricant flowing out from the permeation member. Rolling bearing device.

2. The axial direction of the rolling bearing device includes a horizontal component. A shoulder portion is formed on the inner circumferential surface of the outer ring member adjacent to one side of the outer ring raceway in the axial direction. The storage space is formed on one axial side of the shoulder portion, At least a portion of the aforementioned storage space is located below the shoulder portion in the direction of gravity. The rolling bearing device according to claim 1.

3. The volume of the region of the storage space located below the shoulder portion in the direction of gravity is 5% to 10% of the volume of the permeable member. The rolling bearing device according to claim 2.

4. On the inner circumferential surface of the outer ring member, a shoulder is formed adjacent to one axial side of the outer ring raceway, and a counterbore is formed adjacent to the other axial side of the outer ring raceway. The storage space is formed on the other axial side of the counterbore, At least a portion of the aforementioned storage space is located below the counterbore in the direction of gravity. The rolling bearing device according to claim 1.

5. The region of the inner circumferential surface of the outer ring member in which the storage space is formed includes an inclined surface that slopes radially outward as it approaches the permeable member in the axial direction. A rolling bearing device according to any one of claims 1 to 4.

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