Bearing device

Abstract

The present invention provides a bearing device that prevents grease leakage and also prevents the intrusion of foreign matter. [Solution] The bearing device 1 comprises a bearing 2 and a sensing unit and a power generation unit capable of supplying power to the sensing unit, which are provided at one end of the bearing 2. The sensing unit and the power generation unit are built into the bearing 2, and a sealing member 6 covering the sensing unit and the power generation unit is fitted to the circumferential surface of the fixed-side raceway ring of the bearing 2. The power generation unit has a stator 13 supported by the fixed-side raceway ring and a magnetic ring 5 supported by the rotating-side raceway ring and facing the stator 13 with a gap in between. The sealing member 6 has an annular first lip portion 28 that slides on the circumferential surface of the rotating-side raceway ring and an annular second lip portion that abuts against the stator 13.

Description

Technical Field

[0001] The present invention relates to a bearing device, and more particularly to a technique capable of preventing grease leakage and intrusion of foreign matter such as contaminants. Background Art

[0002] In a conventional bearing device, as shown in Fig. 9, a bearing 100 with a built-in sensor adapted to a bearing size specified in ISO standards or JIS standards is disclosed (Patent Document 1). Prior Art Documents Patent Documents

[0003] Patent Document 1 Japanese Unexamined Patent Application Publication No. 2023-141396 Summary of the Invention Problems to be Solved by the Invention

[0004] In the prior art, a slight radial gap δ, a so-called radial gap, is formed between the stator 101 and the magnetic ring 102, which makes it difficult for grease inside the bearing to leak out, but it is impossible to completely prevent grease leakage. Furthermore, since the magnetic ring 102 is exposed to the outside, it may adsorb magnetic contaminants (abbreviated as "contami"). In this case, the rotation of the bearing 100 may be locked, or an abnormality may occur in a power generation unit such as a stator or a sensing unit due to the contaminants, which makes it impossible to detect predetermined operation information of the bearing 100.

[0005] An object of the present invention is to provide a bearing device capable of preventing grease leakage and preventing intrusion of foreign matter. Means for Solving the Problems

[0006] The bearing device of the present invention comprises a bearing, a sensing unit and a power generation unit capable of supplying power to the sensing unit, provided inside the bearing, The sealing member covering the sensing unit and the power generation unit is fitted onto the circumferential surface of the fixed-side raceway ring in the bearing.

[0007] This configuration includes sealing members to cover the sensing and power generation sections, thereby preventing grease leakage from the bearing and preventing foreign matter from entering the bearing. This improves the operational reliability of bearing devices that incorporate sensing sections and other components.

[0008] The power generation unit includes a stator supported by the fixed-side raceway and a magnetic ring supported by the rotating-side raceway of the bearing and facing the stator with a gap in between. The sealing member may have an annular first lip portion that slides on the circumferential surface of the rotating raceway and an annular second lip portion that contacts the stator.

[0009] In this case, the first lip prevents grease from leaking from inside the bearing to the outside, and also prevents foreign matter such as contaminants from entering the bearing. The second lip prevents grease from inside the bearing from entering the sensing part. Therefore, the operational reliability of bearing devices incorporating sensing parts can be further improved.

[0010] An antenna unit for wirelessly transmitting the output of the sensing unit to the outside of the bearing is built into the bearing. The sealing member has a core metal portion that is fitted to the circumferential surface of the fixed-side raceway ring, and an elastic body fixed to the core metal portion. When the fixed-side raceway is an outer ring, the inner diameter of the core metal portion may be larger than the outer diameter of the antenna portion.

[0011] In this case, the core metal portion of the sealing member is fitted to the circumferential surface of the outer ring, and the inner diameter of this core metal portion is made larger than the outer diameter of the antenna portion. As a result, the output of the sensing unit can be transmitted wirelessly to the outside of the bearing without blocking the radio waves of the antenna portion.

[0012] The stator of the power generation unit is fitted onto the circumferential surface of the fixed-side raceway, and an annular seal portion may be provided at the fitting portion between the stator and the circumferential surface of the fixed-side raceway. Grease from inside the bearing may leak from the fitting portion between the stator and the circumferential surface of the fixed-side raceway. With this configuration, an annular seal portion is provided at the fitting portion, thus preventing grease from leaking from inside the bearing through the fitting portion.

[0013] The specified internal bearing specifications may be changed to match the specified bearing size. The specified bearing internal specifications include the diameter of the rolling elements, the pitch circle diameter of the rolling elements, the number of rolling elements, and the axial position of the racing surfaces of the inner and outer rings. The specified bearing size is the bearing inner diameter, bearing outer diameter, and bearing width as defined in the ISO or JIS standards.

[0014] This configuration allows for a smaller overall size of the bearing device compared to conventional bearing devices with sealing members at the ends, thereby increasing versatility when incorporating the bearing device into various devices.

[0015] When the fixed-side raceway is an outer ring, the fitting portion of the sealing member may be fitted and fixed to the outer circumferential surface of the outer ring. In this case, a larger area of ​​the fitting portion can be secured compared to a configuration in which the fitting portion of the sealing member is fitted and fixed to the inner circumferential surface of the outer ring. This allows the sealing member to be firmly and securely fixed to the outer ring.

[0016] The fitting portion between the sealing member and the outer circumferential surface of the outer ring may be provided with an annular sealing portion separate from the sealing member. In this case, leakage of grease from inside the bearing through the fitting portion can be prevented.

[0017] The seal member includes a core metal part fitted to the outer circumferential surface of the outer ring, and an elastic body fixed to the core metal part, the core metal part may have a standing plate portion that abuts against an end surface of the outer ring, and the elastic body may be fixed to an inner diameter side portion of the standing plate portion and provided on an inner diameter side relative to the inner circumferential surface of the outer ring.

[0018] When the bearing device is assembled into another device, the end surface of the outer ring is used as an abutting portion that abuts against, for example, a step surface of a housing or the like of said another device. If the abutting portion has an elastic body such as a rubber material, an excessive load is applied to the bearing due to the restoring force of the elastic body. According to this configuration, the elastic body is fixed to the inner diameter side portion of the standing plate portion of the core metal part and provided on the inner diameter side relative to the inner circumferential surface of the outer ring, so that application of an excessive load to the bearing can be prevented in advance.

[0019] The seal member may include a core metal part fitted to the outer circumferential surface of the outer ring, and an elastic member integrally molded with the core metal part may be provided at a fitting portion between the core metal part and the outer circumferential surface of the outer ring. In this case, the number of components can be reduced and the structure can be simplified compared to a configuration in which an annular seal part separate from the seal member is provided at the fitting portion. Additionally, the number of assembly steps for the bearing device can be reduced compared to a configuration including a separate annular seal part.

Effects of the Invention

[0020] The bearing device of the present invention is a bearing device comprising a bearing, and a sensing unit and a power generation unit capable of supplying electric power to the sensing unit provided inside the bearing, wherein a seal member covering the sensing unit and the power generation unit is fitted to a circumferential surface of a stationary race in the bearing. Therefore, grease leakage can be prevented and intrusion of foreign matter can be prevented. Note that the circumferential surface refers to either an inner circumferential surface or an outer circumferential surface.

Brief Description of the Drawings

[0021] [Figure 1] It is an exploded perspective view of the bearing device according to the first embodiment of the present invention. [Figure 2]It is a longitudinal sectional view of the bearing device. [Figure 3] It is a side view of the bearing device. [Figure 4] It is a sectional view taken along line IV-IV in FIG. 2. [Figure 5A] It is a partially enlarged view in which a main part of FIG. 2 is partially enlarged. [Figure 5B] It is an enlarged sectional view showing an enlarged portion VB in FIG. 5A. [Figure 5C] It is an enlarged sectional view showing the relationship between the core metal part and the antenna part of the seal member. [Figure 6] It is a longitudinal sectional view of a bearing device according to a second embodiment of the present invention. [Figure 7] It is a longitudinal sectional view of a bearing device according to a third embodiment of the present invention. [Figure 8A] It is a longitudinal sectional view of a bearing device according to a fourth embodiment of the present invention. [Figure 8B] It is a longitudinal sectional view of a bearing device according to a fifth embodiment of the present invention. [Figure 8C] It is a longitudinal sectional view of a bearing device according to a sixth embodiment of the present invention. [Figure 9] It is a longitudinal sectional view of a conventional bearing device. MODE FOR CARRYING OUT THE INVENTION

[0022] [First Embodiment] A bearing device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 5C. The bearing device is applied to, for example, all general industrial machinery such as motors and blowers, wind power generators, vehicles such as automobiles, two-wheeled vehicles and railway vehicles, medical equipment and the like. However, the bearing device is not limited to these applications.

[0023] <Schematic Structure of Bearing Device> As shown in Figure 1, the bearing device 1 according to the first embodiment comprises a bearing 2, an O-ring 3 which is an annular seal portion, a sensing unit assembly 4, a magnetic ring 5, and a sealing member 6 which will be described later. As shown in Figure 2, the components of the bearing device 1 other than the bearing are built into one end of the bearing 2 (the left end in Figure 2). The state of the bearing 2 measured by the sensing unit 7 of the sensing unit assembly 4 is transmitted to the outside of the bearing device 1 and monitored continuously or at predetermined intervals. The components of the bearing device 1 other than the bearing may be collectively referred to as the "sensing unit assembly, etc."

[0024] <Bearings> The bearing 2 in this example is a rolling bearing that is lubricated with grease and comprises an inner ring 8, an outer ring 9, a plurality of rolling elements 10 interposed between the racing surfaces of the inner and outer rings 8 and 9, a cage 11 that holds these rolling elements 10, and a seal 12 provided at the other end of the bearing 2. This rolling bearing is a deep groove ball bearing in which balls are interposed as rolling elements 10 between the opposing racing surfaces 8a and 9a of the inner ring 8 and the outer ring 9.

[0025] The rolling elements 10 consist of steel balls or ceramic balls. The cage 11 is a resin crown-shaped cage. The cage 11 may also be a corrugated cage made of sheet metal. The seal 12 is a contact seal that is fitted and fixed to an outer ring seal groove 9b provided on the inner circumferential surface of the outer ring and contacts an inner ring seal groove 8b provided on the outer circumferential surface of the inner ring. The outer ring seal groove 9b is provided on the inner circumferential surface of the outer ring on the other end of the bearing 2 (the right end in Figure 5B). The inner ring seal groove 8b is radially opposite to the outer ring seal groove 9b. The seal 12 may also be a non-contact seal. This deep groove ball bearing is used, for example, in a fixed outer ring with inner ring rotation, but as will be described later, it may also be used in an inner ring with outer ring rotation.

[0026] Figure 2 is a cross-sectional view taken along line II-II in Figure 3. Figure 4 is a cross-sectional view taken along line IV-IV in Figure 2. As shown in Figures 2 to 4, a first notch 9c is formed on the inner circumferential surface of the outer ring 9 at one end. The first notch 9c is a stepped annular recess. As shown in Figure 5A, a second notch 8c is formed on the outer circumferential surface of the inner ring 8 at one end. The second notch 8c is a stepped annular recess. The first notch 9c is radially opposite to the second notch 8c. These first and second notches 9c and 8c provide space to house the sensing assembly and the like at one end of the bearing 2.

[0027] In the following explanation, as shown in Figure 2, the direction of the bearing center axis AX is referred to as the "axial direction," the direction perpendicular to the bearing center axis AX is referred to as the "radial direction," and the direction around the bearing center axis AX is referred to as the "circumferential direction." Furthermore, the side facing the bearing center axis AX is referred to as the "inner diameter side," and the side moving away from the bearing center axis AX is referred to as the "outer diameter side."

[0028] <Regarding the main dimensions and internal specifications of the bearings> Bearing 2 has been modified to have the specified bearing size shown in Figures 2 to 4 by changing the predetermined internal bearing specifications. The aforementioned specified bearing size is the bearing inner diameter, bearing outer diameter, and bearing width as defined in ISO 15 or JIS 1512-1, and is also referred to as the main dimensions of the bearing. Simply adding the seal member 6 to the conventional technology would result in exceeding the specified bearing size. Therefore, in this embodiment, the predetermined internal bearing specifications have been modified so that even with the addition of the seal member 6 shown in Figures 1 to 3, the bearing size remains within the specified range. The term "bearing interior" refers to the space between the outer ring 9 and the inner ring 8 in the range from one axial end face to the other end face of the outer ring 9.

[0029] Specifically, the bearing 2 of the embodiment, as shown in Figure 5A, has been modified from the internal specifications of a general bearing by, for example, reducing the diameter of the steel balls, increasing the pitch circle diameter (PCD) of the steel balls, increasing the number of steel balls, and moving the axial position P1 of the racing surfaces 8a and 9a on the inner and outer rings 8 and 9 to the side opposite the sealing member (right side in Figure 5A). By moving the axial position P1 of the racing surfaces 8a and 9a, a sensing assembly or the like can be built into one end of the bearing 2. By reducing the diameter of the steel balls, increasing the pitch circle diameter (PCD) of the steel balls, and increasing the number of steel balls, the bearing 2 can achieve a desired load capacity. The axial position P1 of the racing surfaces 8a and 9a, the diameter of the steel balls, the pitch circle diameter (PCD) of the steel balls, and the number of steel balls can be appropriately determined, for example, by simulation and / or testing.

[0030] <Sensing Unit Assembly> As shown in Figures 4 and 5B, the sensing unit assembly 4 includes a stator 13, an insulator 14, a substrate 15, a sensing unit 7, and an antenna unit 17a (Figure 5C). As shown in Figure 5B, the power generation unit G is formed by the stator 13 and a magnetic ring (described later) 5 that faces the stator 13 across a radial gap δ1, also known as a radial gap. In other words, the bearing device includes a sensing unit 7 and a power generation unit G capable of supplying power to the sensing unit 7, which are provided at one end of the bearing 2 (Figure 5A). The power generation unit G is built into the bearing 2 (Figure 5A). The power generated by the power generation unit G can be supplied to the substrate 15 and the sensing unit 7.

[0031] <Stator etc.> The stator 13 is supported by an outer ring 9, which is a fixed-side raceway. The stator 13 has a stator body 19 that holds a substrate 15 and the like, and a stator component 21 that supports a coil assembly 20. The stator body 19 is made of an annular magnetic material. The stator body 19 is formed in a substantially U-shape in longitudinal cross-section, consisting of a disc-shaped portion 19a, an outer diameter cylindrical portion 19b connected to the outer peripheral edge of the disc-shaped portion 19a, and an inner diameter portion 19c connected to the inner peripheral edge of the disc-shaped portion 19a. The disc-shaped portion 19a, the outer diameter cylindrical portion 19b, and the inner diameter portion 19c are integrally formed from a single material, for example, by machining.

[0032] As shown in Figure 5C, the stator body 19 is fitted onto the inner circumferential surface of the outer ring 9, which is the fixed-side raceway ring. Specifically, the outer diameter side cylindrical portion 19b of the stator body 19 is fitted and fixed into the first notch 9c of the outer ring 9. Furthermore, the outer diameter side portion of the disc-shaped portion 19a abuts against the stepped portion 9ca of the first notch 9c. This positions the stator body 19 axially relative to the outer ring 9. With the outer diameter side cylindrical portion 19b fitted into the first notch 9c and the outer diameter side portion of the disc-shaped portion 19a abutting against the stepped portion 9ca, the stator body 19 does not protrude from the end face of the outer ring 9. In other words, the stator body 19 is housed at one end of the bearing 2.

[0033] An O-ring 3 is provided at the fitting portion k1 between the stator body 19 and the inner circumferential surface of the outer ring 9. An annular seal groove 9d is provided in the first notch 9c of the outer ring 9, and the O-ring 3 is fitted into the seal groove 9d. This O-ring 3 prevents grease from leaking from inside the bearing through the fitting portion k1 between the outer diameter cylindrical portion 19b of the stator body 19 and the inner circumferential surface of the outer ring 9. A liquid gasket may be used instead of the O-ring 3 as the annular seal. By filling the seal groove 9d with liquid gasket, grease leakage from the bearing 2 can be prevented in the same way as with the O-ring 3.

[0034] As shown in Figure 1, an annular stator component 21 is fixed to the stator body 19 coaxially with the stator body 19. The stator component 21 is made of an annular magnetic material. As shown in Figure 5B, the stator component 21 is formed in a substantially U-shape in longitudinal cross-section, consisting of a disc-shaped portion 21a, an outer diameter cylindrical portion 21b connected to the outer peripheral edge of the disc-shaped portion 21a, and an inner diameter portion 21c connected to the inner peripheral edge of the disc-shaped portion 21a. The components of the stator component 21 are also integrally formed from a single material by machining or the like, similar to the stator body 19. The outer diameter cylindrical portion 21b of the stator component 21 is fixed to the inner diameter portion of the disc-shaped portion 19a of the stator body 19. The stator body 19 and the stator component 21 are positioned at a predetermined phase while fixed to each other.

[0035] As shown in Figures 1 and 5B, the inner diameter portion 19c of the stator body 19 has a plurality of claw portions 19ca that protrude in one axial direction. The plurality of claw portions 19ca are provided at regular intervals in the circumferential direction. At the same time, the inner diameter portion 21c of the stator component 21 has a plurality of claw portions 21ca that protrude in the other axial direction. The plurality of claw portions 21ca are provided at regular intervals in the circumferential direction. The plurality of claw portions 19ca in the stator body 19 and the plurality of claw portions 21ca in the stator component 21 are arranged alternately with a gap in the circumferential direction. The stator component 21 is positioned and fixed to the stator body 19 at a predetermined phase such that the claw portions 19ca and 21ca are arranged alternately with a predetermined gap in the circumferential direction.

[0036] As shown in Figure 5B, the coil assembly 20 has an annular bobbin 22 with a U-shaped cross-section and a coil 23 wound around the circumferential groove of the bobbin 22. The coil assembly 20 is supported inside the disc-shaped portion 21a, the outer diameter cylindrical portion 21b, and the inner diameter portion 21c of the stator component 21. The stator component 21, on which the coil assembly 20 is supported, is fixed to the stator body 19 as described above.

[0037] <Substrate, sensing unit, etc.> As shown in Figures 4 and 5B, an arc-shaped substrate (also called a "circuit board") 15 and a wireless communication circuit 17 (Figure 5C) are fixed to the disc-shaped portion 19a of the stator body 19 via an insulator 14 or the like. These substrates 15 and wireless communication circuit 17 (Figure 5C) are each fixed to the stator body 19 by a number of screws 24. However, the substrates 15 and wireless communication circuit 17 are not limited to being fixed by screws 24, and may be fixed to the stator body 19 by adhesive or the like, for example.

[0038] As shown in Figure 4, the circuit board 15 is equipped with a sensing unit 7 for monitoring the state of the bearing 2, and a power supply circuit (not shown). The sensing unit 7 is built into the bearing 2. The state of the bearing 2 is synonymous with predetermined operating information for the bearing 2. Examples of the sensing unit 7 include a temperature sensor for measuring the temperature of the bearing 2 and an acceleration sensor for detecting the acceleration acting on the bearing 2. However, the sensing unit 7 is not limited to these sensors.

[0039] <Wireless communication circuit> A wireless communication circuit 17 is built into one end of the bearing 2. The wireless communication circuit 17 includes an antenna unit 17a. The wireless communication circuit 17 transmits the output of a sensing unit 7, such as a temperature sensor or an acceleration sensor, wirelessly to the outside of the bearing 2 using the antenna unit 17a. A control device (not shown) controls the system to output a warning light, a warning sound, a warning display, etc., or to limit the rotation of the bearing 2, or to stop the operation of the bearing 2, etc., when the output of the transmitted sensing unit 7 exceeds a predetermined threshold. An operator who has confirmed the output of a warning light, etc., may stop the drive source of the bearing device.

[0040] <Magnetic rings, etc.> As shown in Figures 1 and 5A, the inner ring 8, which is the rotating raceway, supports the magnetic ring 5. The magnetic ring 5 faces the stator 13 with a radial gap δ1 between them. The magnetic ring 5 is fitted and fixed into the second notch 8c of the inner ring 8. As shown in Figure 5B, the magnetic ring 5 includes a core metal 18 and a multipole magnet 25 fixed to this core metal 18.

[0041] The core metal 18 has a cylindrical portion 18a that fits into the second notch 8c, and a flange portion 18b that extends radially outward from one axial end of the cylindrical portion 18a. The flange portion 18b can increase the overall rigidity of the core metal 18. The multipole magnet 25 is made, for example, by vulcanizing and bonding a magnetic material, which is a mixture of magnetic powder and rubber, to the core metal 18, and then alternately magnetizing the north pole and south pole in the circumferential direction of the bearing.

[0042] The inner surface of the multipole magnet 25 abuts against the stepped portion of the second notch 8c. This positions the magnetic ring 5 axially relative to the inner ring 8. When the cylindrical portion 18a of the mandrel 18 is fitted into the second notch 8c and the inner surface of the multipole magnet 25 abuts against the stepped portion, the magnetic ring 5 does not protrude from the end face of the inner ring 8. In other words, the magnetic ring 5 is housed at one end of the bearing.

[0043] As shown in Figures 1 and 5B, the claw-pole type power generation unit G is formed by the claw portion 19ca of the stator body 19, the claw portion 21ca of the stator component 21, and the magnetic ring 5. The total number of claw portions 19ca and 21ca is equal to the number of poles of the multi-pole magnet 25, that is, the total number of north and south poles. As shown in Figure 5B, each end of the coil 23 drawn from the stator 13 is electrically connected to terminals (not shown) provided on the substrate 15. These terminals are electrically connected to the power supply circuit. As shown in Figure 5A, the AC power output from the power generation unit G is converted to DC power by the power supply circuit as the inner ring 8 rotates. As shown in Figures 4 and 5B, the temperature sensor, acceleration sensor, and wireless communication circuit 17 use the DC power converted by the power supply circuit.

[0044] <Regarding sealing materials> The sealing member 6 (Figure 3) covers the sensing unit 7 and the power generation unit G. When the sealing member 6 is removed from the bearing device 1, the sensing unit 7 and the power generation unit G are exposed. As shown in Figure 5B, the sealing member 6 is fitted and fixed to the inner circumferential surface of the outer ring 9 via the outer diameter side cylindrical portion 19b of the stator body 19. The sealing member 6 has an annular core metal portion 16 that fits onto the inner circumferential surface of the outer ring 9 and an elastic body 26 fixed to the core metal portion 16. In this embodiment, the case where the outer ring is fixed and the inner ring rotates is illustrated, so the sealing member 6 is fitted onto the inner circumferential surface of the outer ring 9. However, when the inner ring is fixed and the outer ring rotates, the sealing member 6 is fitted onto the outer circumferential surface of the inner ring. Also, since the core metal portion 16 is made of a conductive material, it easily absorbs radio waves and can become a barrier to wireless communication. Therefore, as shown in Figure 5C, when the fixed-side raceway is the outer ring 9, the inner diameter 16d of the core metal portion 16 is made larger than the outer diameter 17D of the antenna portion 17a to facilitate wireless communication.

[0045] As shown in Figure 5B, the elastic body 26 is made of rubber or the like and has a seal body 27, a first lip portion 28, and a second lip portion 29. These seal body 27 and the first and second lip portions 28 and 29 are integrally formed. The elastic body 26 is preferably made of a material with low dielectric loss that does not easily absorb radio waves.

[0046] The seal body 27 has a main body portion 27a extending inward from the core metal portion 16, and a bulging portion 27b provided on the axial inner end of the core metal portion 16 and a part of the outer circumference of the core metal portion 16. The bulging portion 27b has a tightening allowance with respect to the outer diameter side cylindrical portion 19b of the stator body 19. In Figure 5B, a part of the bulging portion 27b is shown to be fitted into the outer diameter side cylindrical portion 19b, but this part of the bulging portion 27b is a tightening allowance. When the core metal portion 16 is fitted into the outer diameter side cylindrical portion 19b of the stator body 19, the bulging portion 27b is elastically deformed and contacts the outer diameter side cylindrical portion 19b in a sealed state.

[0047] The annular first lip portion 28 is provided at the inner diameter end of the seal body 27 and slides against the outer circumferential surface of the inner ring 8. Specifically, the first lip portion 28 has an inner lip 28a and an outer lip 28b that branch out in the axial direction inward and outward. The inner lip 28a and the outer lip 28b each have an overlap with the outer circumferential surface of the inner ring 8. In Figure 5B, the respective tip portions of the inner and outer lips 28a and 28b are shown to be fitted into the outer circumferential surface of the inner ring 8, and these respective tip portions are overlaps. Grease is pre-held in the annular groove 30 between the inner lip 28a and the outer lip 28b. The grease held in the annular groove 30 can further reduce the sliding resistance of the first lip portion 28.

[0048] The annular second lip portion 29 branches off from near the radial midpoint of the seal body 27. The second lip portion 29 contacts the stator 13 with an overlap. The second lip portion 29 inclines axially inward as it moves from near the radial midpoint of the seal body 27 towards the inner diameter. The tip of this second lip portion 29 contacts the outer diameter cylindrical portion 21b of the stator component 21 with an overlap. In Figure 5B, the tip of the second lip portion 29 is shown as fitted into the outer diameter cylindrical portion 21b, but this tip portion is an overlap.

[0049] <Effects and Effects> As described above, the bearing device 1 in Figure 5A is provided with a sealing member 6 that covers the sensing unit and the power generation unit G, thereby preventing grease leakage from the bearing and preventing foreign matter from entering the bearing 2. This improves the operational reliability of the bearing device 1, which incorporates the sensing unit and the like. In particular, since the magnetic ring 5 and the stator 13 are covered in a sealed state by the sealing member 6, it is possible to prevent the magnetic ring and the like from attracting contaminants. Therefore, the rotation of the bearing 2 will not lock as desired, and it is possible to prevent abnormalities from occurring in the power generation unit G and the sensing unit due to contaminants. As a result, predetermined operating information of the bearing 2 can be reliably detected.

[0050] As shown in Figure 5B, the sealing member 6 has first and second lip portions 28 and 29. The first lip portion 28 prevents grease inside the bearing from leaking to the outside of the bearing 2 and more reliably prevents foreign matter such as contaminants from entering the bearing. The second lip portion 29 prevents grease inside the bearing from entering the sensing portion 7. Therefore, the operational reliability of the bearing device 1, which incorporates the sensing portion, can be further improved.

[0051] As shown in Figure 5C, the core metal portion 16 of the sealing member 6 is fitted to the inner circumferential surface of the outer ring 9, and the inner diameter 16d of the core metal portion 16 is made larger than the outer diameter 17D of the antenna portion 17a. Therefore, the output of the sensing unit can be transmitted wirelessly to the outside of the bearing 2 without blocking the radio waves of the antenna portion 17a. An O-ring 3 is provided at the fitting portion k1 between the stator body 19 and the inner circumferential surface of the outer ring 9. This prevents grease from leaking from the fitting portion k1. As shown in Figure 5A, the internal specifications of the bearing were changed to specify the bearing size. Therefore, the overall size of the bearing device can be reduced compared to the conventional structure with a sealing member at the end of the bearing device, and the versatility of incorporating the bearing device 1 into various devices can be increased.

[0052] <Regarding other embodiments> In the following description, parts corresponding to matters previously described in each embodiment will be denoted by the same reference numerals, and redundant explanations will be omitted. When only a part of the configuration is described, the other parts of the configuration will be the same as those in the previously described embodiment unless otherwise specified. Identical configurations will produce the same effects. Not only are combinations of the parts specifically described in each embodiment possible, but partial combinations of embodiments are also possible, provided that there are no particular problems with the combination.

[0053] [Second embodiment: Figure 6, configuration in which the seal fitting portion is the outer diameter portion of the outer ring] As shown in Figure 6, when the fixed-side raceway is the outer ring 9, the fitting portion of the sealing member 6A may be fitted and fixed to the outer circumferential surface of the outer ring 9. Specifically, the sealing member 6A includes an annular core metal portion 16A fitted to the outer circumferential surface of the outer ring 9 and an elastic body 26 fixed to the core metal portion 16A. The core metal portion 16A is a metal member made of steel plate or the like. The core metal portion 16A is formed in a substantially L-shape in cross-section with a vertical plate portion 31 that abuts one end surface of the outer ring 9 and a cylindrical portion 32 connected to the outer diameter side end of the vertical plate portion 31.

[0054] A stepped annular recess 9e is formed on the outer circumferential surface of the outer ring 9 on one side (left side in Figure 6) where the sealing member 6A is provided. The cylindrical portion 32 of the core metal portion 16A is fitted and fixed into the annular recess 9e of the outer ring 9. An annular seal portion, separate from the sealing member 6A, is provided at the fitting portion k2 between the core metal portion 16A and the outer circumferential surface of the outer ring 9. An O-ring 3 is used as the annular seal portion. An annular seal groove is provided in the annular recess 9e of the outer ring 9, and the O-ring 3 is fitted into the seal groove.

[0055] When the cylindrical portion 32 is fitted and fixed into the annular recess 9e of the outer ring 9, the outer circumferential surface 32a of the cylindrical portion 32 becomes flush with the outer circumferential surface portion 9D on the other side (right side in Figure 6) of the outer ring 9. As a result, the outer circumferential surface of the outer ring 9 is set to the bearing outer diameter of the specified bearing size. At the same time, the width dimension W1 between the outer surface of the vertical plate portion 31 that abuts against one end face of the outer ring 9 and the other end face of the outer ring 9 is set to the bearing width of the specified bearing size.

[0056] The O-ring 3 prevents grease from leaking from inside the bearing through the fitting portion k2 between the core metal portion 16A and the outer circumferential surface of the outer ring 9. As in the first embodiment, a liquid gasket may be used instead of the O-ring 3. The elastic body 26 is fixed to the inner diameter side portion of the vertical plate portion 31 and is provided on the inner diameter side of the inner circumferential surface of the outer ring 9. The elastic body 26 is made of rubber or the like and has a seal body 27, a first lip portion 28, and a second lip portion 29.

[0057] According to the configuration shown in Figure 6, the fitting portion k2 of the sealing member 6A is fitted and fixed to the outer circumferential surface of the outer ring 9. In this case, a larger area of ​​the fitting portion k2 can be secured compared to a configuration in which the fitting portion of the sealing member is fitted and fixed to the inner circumferential surface of the outer ring. This allows the sealing member 6A to be firmly and securely fixed to the outer ring 9.

[0058] When the bearing device 1 is installed in the device, the outer ring end face is used as a contact point to abut against a stepped surface, such as the housing of the device. However, if there is an elastic material such as rubber on the contact point, the restoring force of this elastic material will place an extra load on the bearing. With this configuration, the elastic body 26 is fixed to the inner diameter side portion of the vertical plate portion 31 in the core metal portion 16A, and is provided on the inner diameter side of the inner circumferential surface of the outer ring 9, thereby preventing excessive load from being applied to the bearing 2. In addition, it provides the same effects as the first embodiment.

[0059] [Third embodiment: Figure 7, a configuration in which the rubber part is integrally molded to the metal fitting part of the seal] In contrast to the second embodiment, as shown in Figure 7, the O-ring in the fitting portion k2 between the sealing member 6B and the outer circumferential surface of the outer ring 9 is eliminated. Furthermore, an elastic member 33 integrally molded with the core metal portion 16A may be provided in the fitting portion k2 between the core metal portion 16A and the outer circumferential surface of the outer ring 9. The elastic member 33 is made of rubber or the like. According to the configuration shown in Figure 7, the number of parts can be reduced and the structure simplified compared to the configuration in Figure 6 in which the fitting portion k2 is equipped with an annular seal portion separate from the seal member. Furthermore, the assembly man-hours for the bearing device 1 can be reduced compared to the configuration equipped with a separate annular seal portion. Other effects and advantages are the same as those of the second embodiment.

[0060] [Embodiments 4-6: Figures 8A-8C, configuration in which a sealing member is fitted to the inner ring surface] Conversely to the first embodiment (see Figure 5A), as shown in Figure 8A, the inner ring 8 may be used as the fixed raceway, and the sealing member 6 may be fitted to the outer circumferential surface of the inner ring 8. In this case, the outer ring 9 becomes the rotating raceway, and the inner and outer lips 28a and 28b of the sealing member 6 slide against the inner circumferential surface of the outer ring 9.

[0061] Conversely to the second embodiment (see Figure 6), as shown in Figure 8B, the inner ring 8 may be used as a fixed raceway, and the sealing member 6A may be fitted to the inner circumferential surface of the inner ring 8. Conversely to the third embodiment (see Figure 7), as shown in Figure 8C, the inner ring 8 may be used as a fixed raceway, and the sealing member 6B may be fitted to the inner circumferential surface of the inner ring 8.

[0062] The bearing device can also be configured as shown in Figures 5A, 6, and 7, with the inner ring 8 acting as the fixed-side raceway and the outer ring 9 as the rotating-side raceway. Furthermore, the bearing device can also be configured as shown in Figures 8A to 8C, with the outer ring 9 acting as the fixed-side raceway and the inner ring 8 as the rotating-side raceway. These bearing devices are described below as examples of proposed designs.

[0063] A bearing device comprising a bearing 2 having an inner ring 8 and an outer ring 9, and a sensing unit 7 and a power generation unit G capable of supplying power to the sensing unit 7, provided at one end of the bearing 2, A bearing device in which the sensing unit 7 and the power generation unit G are built into the bearing 2, and sealing members 6 (6A, 6B) covering the sensing unit 7 and the power generation unit G are fitted to the circumferential surface of the inner ring 8 or the outer ring 9.

[0064] <Other> Of the first and second lip portions 28 and 29 in the sealing member, the second lip portion 29 may be omitted. The magnetic ring 5 may also be a so-called axial gap type power generation unit, facing the stator 13 across an axial gap.

[0065] The bearing 2 is not limited to the deep groove ball bearing described above, but may also be a rolling bearing such as an angular contact ball bearing or a tapered roller bearing. The rolling bearing may be an all-ball type ball bearing without a cage. The bearing 2 may be an open-type rolling bearing without a bearing seal 12, and the grease inside the bearing may be sealed by a cover member on the device side. Bearing 2 can also be fitted with main dimensions other than the specified bearing size. Bearing 2 is not limited to rolling bearings; a sliding bearing may also be used.

[0066] While embodiments for carrying out the present invention have been described above based on the embodiments, the embodiments disclosed herein are illustrative in all respects and are not restrictive. The scope of the present invention is indicated by the claims rather than the foregoing description, and all modifications within the meaning and scope equivalent to the claims are intended to be included. [Explanation of symbols]

[0067] 1...Bearing device, 2...Bearing, 3...O-ring (annular seal part), 5...Magnetic ring, 6,6A,6B...Sealing member, 7...Sensing part, 8...Inner ring (rotating side raceway, stationary side raceway), 9...Outer ring (stationary side raceway, rotating side raceway), 13...Stator, 16,16A...Core metal part, 17a...Antenna part, 26...Elastic body, 28...First lip part, 29...Second lip part, 31...Vertical plate part, 33...Elastic member, G...Power generation part

Claims

1. A bearing device comprising a bearing, a sensing unit and a power generation unit capable of supplying power to the sensing unit, provided inside the bearing, A bearing device in which a sealing member covering the sensing unit and the power generation unit is fitted to the circumferential surface of the fixed-side raceway ring of the bearing.

2. In the bearing device according to claim 1, the power generation unit comprises a stator supported by the fixed-side raceway ring and a magnetic ring supported by the rotating-side raceway ring of the bearing and facing the stator with a gap between them, The sealing member is a bearing device having an annular first lip portion that slides on the circumferential surface of the rotating raceway and an annular second lip portion that contacts the stator.

3. In the bearing device according to claim 1 or claim 2, an antenna unit for wirelessly transmitting the output of the sensing unit to the outside of the bearing is built into the bearing, The sealing member has a core metal portion that is fitted to the circumferential surface of the fixed-side raceway ring, and an elastic body fixed to the core metal portion. A bearing device in which, when the fixed-side raceway is an outer ring, the inner diameter of the core metal portion is larger than the outer diameter of the antenna portion.

4. A bearing device according to claim 1 or claim 2, wherein the stator of the power generation unit is fitted onto the circumferential surface of the fixed-side raceway, and an annular seal portion is provided at the fitting portion between the stator and the circumferential surface of the fixed-side raceway.

5. A bearing device according to claim 1 or claim 2, wherein the specified internal bearing specifications are changed to obtain a specified bearing size.

6. A bearing device according to claim 1 or claim 2, wherein, when the fixed raceway is an outer ring, the fitting portion of the sealing member is fitted and fixed to the outer circumferential surface of the outer ring.

7. A bearing device according to claim 6, wherein the fitting portion between the seal member and the outer circumferential surface of the outer ring is provided with an annular seal portion separate from the seal member.

8. In the bearing device according to claim 6, the sealing member includes a core metal portion fitted to the outer circumferential surface of the outer ring and an elastic body fixed to the core metal portion. The bearing device wherein the core portion has a vertical plate portion that abuts against the end face of the outer ring, and the elastic body is fixed to the inner diameter side portion of the vertical plate portion and is provided on the inner diameter side of the inner circumferential surface of the outer ring.

9. The bearing device according to claim 6, wherein the sealing member includes a core metal portion fitted to the outer circumferential surface of the outer ring, and the fitting portion between the core metal portion and the outer circumferential surface of the outer ring is provided with an elastic member integrally molded with the core metal portion.

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