Bearing device

Abstract

To provide a bearing device that can improve assembly efficiency and suppress the decrease in power generation performance. [Solution] The bearing device 1 comprises a bearing, a sensing unit 7, a substrate 15, and a power generation unit. The sensing unit 7, the substrate 15, and the power generation unit are built into the bearing, and the power generation unit has a stator supported by an outer ring and a magnetic ring supported by an inner ring and facing the stator with a radial gap between them. The stator includes a stator body 19 to which the substrate 15 is fixed, and a stator component 21 that supports a coil assembly 20 including a coil wound around an annular component 22. A first engaging portion 41 is provided on the annular component 22, and the first engaging portion 41 engages with a first engaged portion of the stator component 21. A second engaging portion 43 is provided on the stator component 21, and the second engaging portion 43 engages with a second engaged portion 44 of the stator body 19, and the second engaged portion 44 is provided at a predetermined phase with respect to the substrate fixing position on the stator body 19.

Description

[[TECHNICAL FIELD]]

[0001] The present invention relates to a bearing device, and more particularly to a technology capable of improving assemblability and suppressing a decrease in power generation performance. [[BACKGROUND ART]]

[0002] In a conventional bearing device, as shown in FIG. 12, a bearing 100 with a built-in sensor that conforms to bearing sizes specified in ISO standards or JIS standards is disclosed (Patent Document 1). [[PRIOR ART DOCUMENTS]] [[PATENT DOCUMENTS]]

[0003] [[Patent Document 1]] Japanese Unexamined Patent Publication No. 2023-141396 [[SUMMARY OF THE INVENTION]] [[Problems to be Solved by the Invention]]

[0004] In a stator 101 according to the prior art, an annular stator component 111 that supports a coil assembly 110 is assembled to an annular stator main body 112. Furthermore, in the prior art, the drawing position of the magnet wire of the coil and the assembly phase of the stator component 111 are not mechanically determined. As a result, when assembling the stator component 111 including the coil to the stator main body 112, the following problems have occurred.

[0005] It is difficult to align the phase between the drawing position of the coil wire and a substrate 113 supported by the stator main body 112, as well as the phase between claw portions provided on inner diameter portions of the stator main body 112 and the stator component 111, resulting in poor assemblability and a possible decrease in power generation performance. For example, if there is a large phase shift between the terminal of the substrate 113 and the drawing position of the coil wire, there is a concern that wire breakage or the like may occur due to the lengthening of the drawn coil wire.

[0006] Furthermore, in order to maintain the desired power generation performance, the claw portion of the stator body 112 and the claw portion of the stator component 111 adjacent to the claw portion must be positioned with a predetermined gap in the circumferential direction. If the phase of the stator body 112 and the stator component 111 is undesirably misaligned, the gap between adjacent claw portions in the circumferential direction will deviate from the predetermined value, which may prevent the maintenance of the desired power generation performance.

[0007] The objective of the present invention is to provide a bearing device that can improve ease of assembly and suppress the deterioration of power generation performance. [Means for solving the problem]

[0008] The bearing device of the present invention comprises a bearing, a sensing unit, a substrate supporting the sensing unit, and a power generation unit capable of supplying power to the sensing unit, wherein the sensing unit, the substrate, and the power generation unit are built into the bearing, and the power generation unit comprises a stator supported by the fixed-side raceway of the bearing, and a magnetic ring supported by the rotating-side raceway of the bearing and facing the stator with a radial gap between them, The stator includes a stator body to which the substrate is fixed, and a stator component that supports a coil assembly including a coil wound around an annular component. The annular component is provided with a first engaging portion, and the first engaging portion engages with a first engaged portion of the stator component, The stator component is provided with a second engaging portion, the second engaging portion engages with a second engaged portion of the stator body, and the second engaged portion is provided at a predetermined phase with respect to the substrate fixing position on the stator body. The aforementioned phase is determined as appropriate by either testing, simulation, or both.

[0009] In this configuration, when assembling the bearing device, the first engaging portion of the annular component is engaged with the first engaged portion of the stator component. Furthermore, the second engaging portion of the stator component is engaged with the second engaged portion of the stator body. This configuration mechanically determines the phase between the substrate fixed to the stator body and the coil pull-out position supported by the stator component. This configuration prevents unwanted phase misalignment between the stator body and the stator component, and makes it possible to easily determine the phase between the substrate and the coil pull-out position. Therefore, it is possible to improve assembly efficiency and suppress the decrease in power generation performance compared to conventional structures.

[0010] When the fixed-side raceway is an outer ring, the first engaging portion may be a protrusion provided on the outer diameter of the annular component, and the first engaged portion may be a recess provided on the stator component. In this case, the protrusion can be integrally molded on the outer diameter of the annular component, and the recess can be easily formed on a part of the stator component by machining or the like. Therefore, it becomes possible to assemble the annular component in conjunction with the stator component without adding any new parts.

[0011] The second engaging portion may be a claw portion provided on the stator component, and the second engaged portion may be a hole provided in the stator body. In this case, the claw portion can be integrally molded into a part of the stator component, and the hole can be easily formed in a part of the stator body by machining or the like. Therefore, it becomes possible to assemble the stator component in phase with the stator body without adding any new parts.

[0012] If multiple locations are provided where the phases of the first engaging portion and the first engaged portion, and the phases of the second engaging portion and the second engaged portion are respectively arranged unequally around the circumference, the respective phases may be arranged unequally. In this case, assembly errors can be prevented by reducing the number of combinations when engaging the first engaged portion of the annular component with the first engaged portion of the stator component. Similarly, assembly errors can be prevented by reducing the number of combinations when engaging the second engaging portion of the stator component with the second engaged portion of the stator body. [Effects of the Invention]

[0013] The bearing device of the present invention comprises a bearing, a sensing unit, a substrate supporting the sensing unit, and a power generation unit capable of supplying power to the sensing unit, wherein the sensing unit, the substrate, and the power generation unit are built into the bearing, and the power generation unit comprises a stator supported on the fixed-side raceway of the bearing and a magnetic ring supported on the rotating-side raceway of the bearing and facing the stator with a radial gap between them. The stator includes a stator body to which the substrate is fixed and a stator component supporting a coil assembly including a coil wound around an annular component, wherein the annular component is provided with a first engaging portion, the first engaging portion engages with a first engaged portion of the stator component, and the stator component is provided with a second engaging portion, the second engaging portion engages with a second engaged portion of the stator body, and the second engaged portion is provided at a predetermined phase with respect to the substrate fixing position on the stator body. Therefore, the assembly of the bearing device can be improved and the decrease in power generation performance can be suppressed. [Brief explanation of the drawing]

[0014] [Figure 1] This is a longitudinal cross-sectional view of a bearing device according to the first embodiment of the present invention. [Figure 2A] This is a cross-sectional view taken along the line IIA-IIA in Figure 1. [Figure 2B] This is a magnified view of section IIB in Figure 2A. [Figure 2C]It is a partially enlarged view showing an enlarged view of the IIC section in FIG. 2A. [Figure 3] It is a sectional view taken along line III-III in FIG. 1. [Figure 4] It is a partially enlarged view obtained by partially enlarging the main part of FIG. 1. [Figure 5] It is an enlarged sectional view showing an enlarged sensing assembly and the like of the bearing device. [Figure 6] It is a partially enlarged view showing an enlarged view of the VI section in FIG. 1. [Figure 7] It is an exploded perspective view of a stator main body, a coil assembly and stator components in the bearing device. [Figure 8] It is a longitudinal sectional view of a bearing device according to a second embodiment of the present invention. [Figure 9] It is an exploded perspective view of a stator main body, a coil assembly and stator components in a bearing device according to a third embodiment of the present invention. [Figure 10] It is a side view of the stator main body and the like of the bearing device as viewed from the axial direction. [Figure 11] It is a longitudinal sectional view of the stator main body and the like. [Figure 12] It is a longitudinal sectional view of a conventional bearing device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] [First Embodiment] A bearing device according to an embodiment of the present invention will be described with reference to FIGS. 1 to 7. The bearing device is applied to, for example, all 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.

[0016] <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, a contact-type sealing member 6, and a seal lip sliding member 38. In the bearing device 1, components other than the bearing are built into one end of the bearing 2 (the left end in Figure 1). 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 other than the bearing in the bearing device 1 are sometimes collectively referred to as the "sensing unit assembly, etc."

[0017] <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.

[0018] 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 4). 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.

[0019] As shown in Figures 2A and 3, a first stepped portion 9c is formed on the inner circumferential surface of the outer ring 9 at one end. The first stepped portion 9c is a stepped annular recess, also referred to as the "first notch." As shown in Figure 4, a second stepped portion 8c is formed on the outer circumferential surface of the inner ring 8 at one end. The second stepped portion 8c is a stepped annular recess, also referred to as the "second notch." The first stepped portion 9c faces the second stepped portion 8c in the radial direction. These first and second stepped portions 9c and 8c provide space for housing the sensing assembly and the like at one end of the bearing 2.

[0020] In the following explanation, as shown in Figure 1, 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."

[0021] <Regarding the main dimensions and internal specifications of the bearings> Bearing 2 has been modified to have the specified bearing size shown in Figure 1 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 are modified so that the bearing remains within the specified bearing size even with the addition of the seal member 6 shown in Figure 1.

[0022] Specifically, as shown in Figure 4, the bearing 2 of the embodiment 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 4). 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.

[0023] <Sensing Unit Assembly> As shown in Figure 5, the sensing unit assembly 4 includes an annular fixing component RP, a stator 13, a substrate 15, the sensing unit 7 shown in Figure 1, and an antenna unit 17a. As shown in Figure 4, 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. That is, the bearing device 1 is provided at one end of the bearing 2 and includes a sensing unit 7 and a power generation unit G capable of supplying power to the sensing unit 7. The power generation unit G is built into the bearing 2. The power generated by the power generation unit G can be supplied to the substrate 15 and the sensing unit 7.

[0024] <Regarding fixing parts, etc.> The fixed component RP maintains the phase of the stator 13 in the power generation section G. Furthermore, as shown in Figure 5, the stator 13 and the sensing section 7 are fixed to the fixed component RP. The fixed component RP is a flat, annular resin component and is provided coaxially with the stator body 19 on its axial outer surface, which will be described later. The first stepped portion 9c restricts the axial position of the fixed component RP. Furthermore, the sensing section assembly 4, including the fixed component RP, the stator 13, and the sensing section 7, is housed in the bearing by the first and second stepped portions 9c and 8c.

[0025] As shown in Figures 3 and 7, the fixing component RP has a disc-shaped fixing component body 34 and a plurality of engaging portions 35 provided on one surface of the fixing component body 34. The plurality of engaging portions 35 are provided at predetermined phases on the fixing component body 34. These fixing component body 34 and the plurality of engaging portions 35 are integrally formed from the same resin material, but it is also possible to form them separately and fix the plurality of engaging portions 35 to one surface of the fixing component body 34. The stator body 19 and the fixing component RP are fixed to each other by adhesive or joining, or the fixing component RP is insert-molded into the stator body 19.

[0026] As shown in Figure 4, the stator 13 is supported by the outer ring 9, which is a fixed-side raceway. The stator 13 has a stator body 19 to which fixed components RP, a substrate 15, and an antenna section 17a (Figure 1) are fixed, and a stator component 21 to which the coil assembly 20 is supported. The stator body 19 is made of an annular magnetic material. As shown in Figure 5, the stator body 19 is formed in a substantially U-shape in longitudinal cross-section by 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.

[0027] As shown in Figure 7, the disc-shaped portion 19a of the stator body 19 is provided with engaged portions 36 that engage with each engaging portion 35 of the fixed component RP. The engaging portion 35 of the fixed component RP has a configuration in which a large-diameter protrusion 35a (Figure 3) and a small-diameter protrusion 35b (Figure 2A) are superimposed in the axial direction. In each engaging portion 35, a large-diameter protrusion 35a (Figure 3) and a small-diameter protrusion 35b (Figure 2A) are provided coaxially and are formed in a cylindrical shape extending in the axial direction. The small-diameter protrusion 35b is smaller in diameter than the large-diameter protrusion. The axial base end of the large-diameter protrusion is provided on one surface of the fixing component body 34, and the small-diameter protrusion 35b is provided so as to overlap the axial tip of the large-diameter protrusion.

[0028] The large-diameter protrusion 35a is inserted through the through-hole, which is the engaged portion 36 of the stator body 19 shown in Figure 3. At the same time, the small-diameter protrusion 35b is fitted into the hole 15a provided in the substrate 15 shown in Figure 2A. The substrate 15 and the fixing component RP are firmly fixed together by applying, for example, an adhesive, between the hole 15a of the substrate 15 and the small-diameter protrusion 35b of the fixing component RP. Note that the method of fixing the substrate 15 to the fixing component RP is not limited to the adhesive; for example, bonding with an insulating material such as potting material or heat welding are also possible. In the state in which the small-diameter protrusion 35b is fitted into the hole 15a of the substrate 15, the axial inner surface of the substrate 15 is supported by the stepped surface of the large-diameter protrusion.

[0029] As shown in Figure 5, the coil assembly 20 comprises an annular component 22 and a coil 23. In this embodiment, an annular bobbin with a U-shaped cross-section is used as the annular component 22. The coil 23 is wound around the circumferential groove of the bobbin. The base end, or root, of the coil 23 is fixed at a predetermined phase in the circumferential groove of the bobbin. 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 coil assembly 20 is also coaxially supported by the stator component 21.

[0030] <Regarding phase alignment between stator components and coil assembly> As shown in Figure 7, a first engaging portion 41 is provided on the bobbin, which is an annular component 22. Figure 2B is a magnified view of portion IIB in Figure 2A, and Figure 2C is a magnified view of portion IIC in Figure 2A. As shown in Figures 2A to 2C, the first engaging portion 41 on the bobbin engages with the first engaged portion 42 on the stator component 21, determining the phase between the stator component 21 and the coil assembly 20, and preventing the coil assembly 20 from rotating relative to the stator component 21.

[0031] When the fixed-side raceway is the outer ring 9 (Figure 2A), the first engaging portion 41 is a protrusion provided on the outer diameter portion of the annular component 22, as shown in Figure 7. Hereafter, the first engaging portion 41 may be referred to as the protrusion 41. The protrusion 41 is a projection that extends radially outward from other parts of the outer diameter portion of the annular component 22. Furthermore, as shown in Figures 2B and 2C, the first engaged portion 42 is a recess provided on the outer diameter side cylindrical portion 21b of the stator component 21, that is, a groove that extends a predetermined small distance in the circumferential direction on the outer diameter side cylindrical portion 21b. Hereafter, the first engaged portion 42 may be referred to as the recess 42. The protrusion 41 and the recess 42 are formed by machining or the like.

[0032] As shown in Figure 2A, the circumferential positions, or phases, of the protrusions 41 on the bobbin and the recesses 42 on the stator component 21 are provided at multiple locations that are equally spaced circumferentially. In this example, three protrusions 41 are provided on the outer diameter of the bobbin at 120-degree intervals in the circumferential direction.

[0033] However, the single protrusion 41 shown in Figure 2C is wider than the other two protrusions 41 shown in Figure 2B, etc., in order to determine the phase of the coil 23's withdrawal position P23. As shown in Figure 2A, the three recesses 42 in the stator component 21 are formed to have a circumferential width corresponding to the circumferential width of the protrusions 41 that they engage with. The radial height of the three protrusions 41 is uniform and is set so as not to protrude beyond the outer circumferential surface 21ba of the outer diameter cylindrical portion 21b shown in Figure 7.

[0034] <Regarding phase alignment between the stator body and stator components> The stator component 21, on which the coil assembly 20 is supported, is positioned and fixed to the stator body 19 at a predetermined phase. Specifically, the stator component 21 is provided with a second engaging portion 43, which engages with a second engaged portion 44 of the stator body 19. The second engaged portion 44 is positioned at a predetermined phase with respect to the substrate fixing position on the stator body 19.

[0035] As shown in Figures 3 and 7, the second engaging portion 43 is a claw portion provided on the stator component 21. The second engaged portion 44 is a hole provided in the stator body 19. Hereafter, the second engaging portion 43 may be referred to as the claw portion 43, and the second engaged portion 44 may be referred to as the hole 44. The claw portion 43 is integrally formed on the outer diameter cylindrical portion 21b (Figure 7) of the stator component 21 by machining or the like. The hole 44 is formed on the disc-shaped portion 19a of the stator body 19 by machining or the like. The claw portions 43 of the stator component 21 and the holes 44 of the stator body 19 are located at multiple points with unequal circumferential positions, i.e., phases, on the circumference. In this example, as shown in Figure 7, three claw portions 43 are provided at unequal circumferential positions on the axial tip edge of the outer diameter side cylindrical portion 21b of the stator component 21.

[0036] Each claw portion 43 protrudes axially more than other parts of the axial tip edge of the outer diameter cylindrical portion 21b. Furthermore, each hole 44 of the stator body 19 is a slit-shaped hole extending in the circumferential direction. When each claw portion 43 of the stator component 21 is engaged with the hole 44 of the stator body 19, each claw portion 43 is set so as to not protrude axially inward from the inner surface of the disc-shaped portion 19a, as shown in Figure 6.

[0037] <Substrate, sensing unit, etc.> As shown in Figure 2A, the substrate (also called a "circuit board") 15 is provided in an arc shape along the disc-shaped portion 19a of the stator body 19 in a plan view of the substrate 15. The substrate 15 is provided, for example, over a circumferential range of approximately 270 degrees along the disc-shaped portion 19a, and the wireless communication circuit 17 is fixed at the remaining circumferential position on the disc-shaped portion 19a.

[0038] As shown in Figure 7, a plurality of projections 37 protruding in the axial direction are provided on one surface of the fixing component body 34. These projections 37 are formed in a cylindrical shape extending in the axial direction and are positioned at a different phase from the plurality of engaging portions 35. The plurality of projections 37, like the plurality of engaging portions 35, are integrally formed on the fixing component body 34 from the same resin material as the fixing component body 34. The multiple protrusions 37 are fitted into holes provided in the disc-shaped portion 19a of the stator body 19. A wireless communication circuit 17 is fitted and fixed to the axial tip portion of each protrusion 37.

[0039] As shown in Figure 2A, 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.

[0040] <Wireless communication circuit> As shown in Figures 2A and 6, 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 antenna unit 17a is fixed to the stator body 19 of the stator 13 (Figure 6). The antenna unit 17a wirelessly transmits the output of the sensing unit 7 (Figure 2A) to the outside of the bearing 2. In other words, the wireless communication circuit 17 uses the antenna unit 17a to wirelessly transmit the output of the sensing unit 7 (Figure 2A), such as a temperature sensor or acceleration sensor, to the outside of the bearing 2. A control device (not shown) controls the system to output a warning light, warning sound, warning display, etc., or to limit the rotation of the bearing 2, or to stop the operation of the bearing 2, etc., when the transmitted output of the sensing unit 7 (Figure 2A) 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.

[0041] <Magnetic rings, etc.> As shown in Figure 5, the inner ring 8, which is the rotating raceway, supports a 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 to the second stepped portion 8c of the inner ring 8. The magnetic ring 5 includes a core metal 18 and a multipole magnet 25 fixed to this core metal 18.

[0042] The core metal 18 has a cylindrical portion 18a that fits into the second stepped portion 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 N pole and S pole in the circumferential direction of the bearing.

[0043] The inner surface of the multipole magnet 25 abuts against the stepped portion of the second stepped portion 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 stepped portion 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.

[0044] As shown in Figure 7, 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 shown in Figure 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.

[0045] As shown in Figure 2A, the lead portion 23a of the coil 23 drawn out from the stator 13 is electrically connected to a terminal Tm provided on the circuit board 15. The terminal Tm is electrically connected to the power supply circuit. By aligning the phases of the stator component 21 and the coil assembly 20, and the stator body 19 and the stator component 21, the phase between the position of the terminal Tm on the circuit board 15 fixed to the stator body 19 and the lead position P23 of the coil 23 supported by the stator component 21 is mechanically determined.

[0046] As the inner ring 8 rotates, the AC power output from the power generation unit G (Figure 1) is converted to DC power by the power supply circuit. The wireless communication circuit 17, which includes the temperature sensor, acceleration sensor, and antenna unit 17a, uses the DC power converted by the power supply circuit.

[0047] <Regarding sealing materials> The sealing member 6 in Figure 1 covers the sensing unit 7, the antenna unit 17a, and the power generation unit G. When the sealing member 6 is removed from the bearing device 1, the sensing unit 7, the antenna unit 17a, and the power generation unit G are exposed. As shown in Figure 5, 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.

[0048] As shown in Figure 6, the sealing member 6 has an annular sealing reinforcement member 16 in the portion of the sealing member 6 that is not axially opposed to the antenna portion 17a. The portion of the sealing member 6 that is axially opposed to the antenna portion 17a is a sealing reinforcement member cutout 40 in which the sealing reinforcement member 16 is not provided. The sealing reinforcement member cutout 40 is, for example, an arc-shaped hole along the circumferential direction. A part of the elastic body 26, which will be described later, is embedded in the sealing reinforcement member cutout 40.

[0049] As shown in Figure 5, the annular seal reinforcement member 16 is formed in a substantially L-shape in cross-section by a vertical plate-shaped reinforcement member body 16a, the majority of which is exposed on its outer surface, and a cylindrical portion 16b connected to the outer diameter edge of the reinforcement member body 16a. The reinforcement member body 16a and the cylindrical portion 16b are integrally molded from a steel plate or the like. The seal reinforcement member weight-reducing portion 40 (Figure 6) is formed in the reinforcement member body 16a. The cylindrical portion 16b of the seal reinforcement member 16 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 seal reinforcement member 16 is also referred to as the core metal portion 16.

[0050] The sealing member 6 has an elastic body 26 fixed to the sealing reinforcing member 16. The elastic body 26 is made of rubber or the like and has a sealing body 27, a first lip portion 28 as a sealing lip, and a second lip portion 29. These sealing body 27 and the first and second lip portions 28 and 29 are integrally formed.

[0051] The seal body 27 has a main body portion 27a integrally molded with the seal reinforcing member 16, and a bulging portion 27b provided on the axial inner end of the seal reinforcing member 16 and a part of the outer circumference of the seal reinforcing member 16. The bulging portion 27b has a tolerance for interference with the outer diameter side cylindrical portion 19b of the stator body 19. In Figure 5, a part of the bulging portion 27b is shown to be fitted into the outer diameter side cylindrical portion 19b, but the part of the bulging portion 27b is the tolerance for interference. When the seal reinforcing member 16 is fitted into the outer diameter side cylindrical portion 19b of the stator body 19, the bulging portion 27b is elastically deformed and comes into contact with the outer diameter side cylindrical portion 19b in a sealed state.

[0052] The annular first lip portion 28 is provided on the inner diameter side of the seal body 27 and slides against the seal lip sliding member 38, which will be described later. Specifically, the first lip portion 28 has a radial lip 28b that slides against the cylindrical portion 38a of the seal lip sliding member 38 and an axial lip 28a that slides against the vertical plate portion 38b of the seal lip sliding member 38. The radial lip 28b protrudes inward from the inner diameter side tip of the seal body 27. The axial lip 28a is inclined outward from the inner surface of the inner diameter side portion of the seal body 27 as it moves axially inward.

[0053] The axial lip 28a and radial lip 28b have an overlap with respect to the seal lip sliding member 38. In Figure 5, the respective tip portions of the axial lip 28a and radial lip 28b are shown to be fitted into the seal lip sliding member 38, and these respective tip portions are overlaps. Grease is pre-held in the annular groove 30 between the axial lip 28a and the radial lip 28b. The grease held in the annular groove 30 can further reduce the sliding resistance of the first lip portion 28.

[0054] 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 toward the inner diameter. The tip portion of this second lip portion 29 contacts the outer diameter side cylindrical portion 21b of the stator component 21 with an overlap. In Figure 5, the tip portion of the second lip portion 29 is shown as fitted into the outer diameter side cylindrical portion 21b, but this tip portion is an overlap.

[0055] <Regarding seal lip sliding members> The seal lip sliding member 38 is made of a non-magnetic material such as an austenitic stainless steel plate or aluminum. Examples of the stainless steel plate include SUS304. The seal lip sliding member 38 is formed in an L-shape in cross-section with a cylindrical portion 38a and a vertical plate portion 38b.

[0056] The cylindrical portion 38a is fitted onto the second stepped portion 8c, which is the circumferential surface of the inner ring 8. The vertical plate portion 38b extends radially outward from one axial end of the cylindrical portion 38a and abuts against the outer surface of the magnetic ring 5. The cylindrical portion 38a and the vertical plate portion 38b are integrally formed from a single material, for example by machining. The outer circumferential surface of the cylindrical portion 38a in the seal lip sliding member 38 slides against the radial lip 28b. The outer surface of the vertical plate portion 38b in the seal lip sliding member 38 slides against the axial lip 28a.

[0057] <Effects and Effects> As described above, the bearing device 1 shown in Figure 1 is equipped with a sealing member 6 that covers the sensing unit 7, the antenna unit 17a, and the power generation unit G. Therefore, it is possible to prevent grease inside the bearing from leaking to the outside of the bearing 2, and to further prevent foreign matter from entering the bearing. Since the sealing member 6 has an annular sealing reinforcing member 16, the overall rigidity of the sealing member can be increased compared to the conventional structure without a sealing reinforcing member. Therefore, even if the internal pressure of the bearing 2 changes or the axial clearance of the bearing 2 is displaced, the sealing performance is not impaired, and the sealing performance can be improved compared to the conventional structure.

[0058] Furthermore, since the annular seal reinforcement member 16 is provided in all parts except those facing the antenna portion 17a in the axial direction, it is possible to wirelessly transmit the output of the sensing unit 7 to the outside of the bearing 2 without blocking the radio waves of the antenna portion 17a.

[0059] When assembling the bearing device 1, as shown in Figure 7, the protruding portion 41 of the bobbin 22 is engaged with the recessed portion 42 of the stator component 21 (Figures 2B and 2C). Furthermore, the claw portion 43 of the stator component 21 is engaged with the hole 44 in the stator body 19. This configuration mechanically determines the phase between the substrate 15 fixed to the stator body 19 and the pulling position P23 of the coil 23 supported by the stator component 21, as shown in Figure 2A.

[0060] This configuration prevents unwanted phase misalignment between the stator body 19 and the stator components 21, and also allows for easy determination of the phase between the circuit board 15 and the coil 23's lead-out position P23. Therefore, it is possible to improve assembly efficiency and suppress the decrease in power generation performance compared to conventional structures.

[0061] A protrusion 41 can be integrally molded onto the outer diameter of the bobbin 22, and a recess 42 can be easily formed on a part of the stator component 21 by machining or other means. Therefore, it is possible to assemble the bobbin 22 in phase with the stator component 21 without adding any new parts. As shown in Figure 7, the claw portion 43 can be integrally molded into a part of the stator component 21, and the hole 44 can be easily formed in a part of the stator body 19 by machining or the like. Therefore, it is possible to assemble the stator component 21 in phase with the stator body 19 without adding any new parts.

[0062] <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.

[0063] [Second embodiment: Figure 8, configuration in which a sealing member is fitted to the outer circumference of the inner ring] Conversely to the first embodiment, as shown in Figure 8, the inner ring 8 may be used as the fixed-side 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-side raceway, and the first lip portion 28 of the sealing member 6 slides against the sealing lip sliding member 38 fitted to the stepped portion 9c of the outer ring 9.

[0064] [Third Embodiment: Figures 9-11, Air-core coil] A coil assembly is not limited to a configuration that includes a coil wound on a bobbin. As shown in Figure 9, for example, a coil assembly 20 may be formed by solidifying a coil 23 in an annular shape with a resin material 45 such as varnish. In this case, the resin material 45 corresponds to the "annular component".

[0065] <Regarding phase alignment between stator components and coil assembly> Figure 10 is a cross-sectional view along line XX of Figure 11, and Figure 11 is a longitudinal cross-sectional view of the stator body, etc. As shown in Figures 10 and 11, a rectangular protrusion (first engaging portion) 41 is provided on a part of the circumferential direction of the outer surface of the resin material 45 (Figure 9). The lead portion 23a of the coil 23 (Figure 9) protrudes from the outer surface of the protrusion 41 and is electrically connected to a terminal provided on a substrate (not shown).

[0066] As shown in Figure 9, the outer diameter cylindrical portion 21b of the stator component 21 is provided with a recess (first engaged portion) 42 into which the convex portion 41 engages. The recess 42 is a rectangular hole-shaped notch into which the rectangular convex portion 41 engages. By engaging the rectangular convex portion 41 with this rectangular hole-shaped notch, the phase alignment between the stator component 21 and the coil assembly 20 can be easily and reliably performed. The phase alignment between the stator body 19 and the stator component 21 is configured the same as in the first embodiment. This configuration reduces the number of parts and simplifies the structure compared to the first embodiment which has a bobbin, thereby reducing manufacturing costs. In addition, it provides the same effects as the first embodiment.

[0067] [Third Embodiment: Unequal Distribution on the Circumference] In the first embodiment, as shown in Figure 2A, the circumferential positions, or phases, of the convex portion 41 of the bobbin 22 and the recessed portion 42 of the stator component 21 are provided at multiple locations that are equally spaced around the circumference. However, it is not limited to this equally spaced circumferential positioning. The circumferential positions, or phases, of the convex portion 41 of the bobbin 22 and the recessed portion 42 of the stator component 21 may be provided at multiple locations, and the circumferential positions at multiple locations may be unequally spaced around the circumference. Furthermore, as shown in Figure 3, the circumferential positions, or phases, of the claw portion 43 of the stator component 21 and the hole 44 of the stator body 19 may be provided at multiple locations, and the circumferential positions at multiple locations may be unequally spaced around the circumference.

[0068] In this case, assembly errors can be prevented by reducing the number of combinations when engaging the protruding part of the bobbin with the recessed part of the stator component 21. Furthermore, assembly errors can be prevented by reducing the number of combinations when engaging the claw part 43 of the stator component 21 with the hole 44 of the stator body 19.

[0069] Regarding the number of protrusions on the bobbin, if we only consider preventing the coil assembly from rotating relative to the stator component, at least one is sufficient. However, if two or more protrusions are provided, it becomes difficult to clearly determine the phase of the coil's lead-out position. In this case, the circumferential width of the protrusion should be varied to determine the phase of the coil's lead-out position. Furthermore, in the first embodiment, as shown in Figure 3, there are three holes 44 in the stator body 19 and three claws 43 in the stator component 21, but at least one is sufficient to determine the phase.

[0070] The bearing device can also be configured as shown in Figure 1, for example, with the inner ring 8 as the fixed-side raceway and the outer ring 9 as the rotating-side raceway. Alternatively, the bearing device can be configured as shown in Figure 8, for example, with the outer ring 9 as the fixed-side raceway and the inner ring 8 as the rotating-side raceway. These bearing devices 1 are described below as reference examples.

[0071] A bearing device comprising a bearing 2 having an inner ring 8 and an outer ring 9, a sensing unit 7, a substrate 15 supporting the sensing unit 7, and a power generation unit G capable of supplying power to the sensing unit 7, wherein the sensing unit 7, the substrate 15, and the power generation unit G are built into one end of the bearing 2, and the power generation unit G has a stator 13 supported by either the inner ring 8 or the outer ring 9, and a magnetic ring 5 supported by the other raceway and facing the stator 13 with a gap δ1 between them, The stator 13 includes a stator body 19 to which the substrate 15 is fixed, and a stator component 21 that supports a coil assembly 20 including a coil 23 wound around an annular component 22. The annular component 22 is provided with a first engaging portion 41, and the first engaging portion 41 engages with the first engaged portion 42 of the stator component 21, and A bearing device in which a second engaging portion 43 is provided on the stator component 21, the second engaging portion 43 engages with a second engaged portion 44 of the stator body 19, and the second engaged portion 44 is provided at a predetermined phase with respect to the substrate fixing position on the stator body 19.

[0072] As an air-core coil, a coil assembly 20 may be constructed by winding a fusion-compatible coil 23 in a ring shape and fusing it. Of the first and second lip portions 28 and 29 of the sealing member 6, the second lip portion 29 may be omitted. As a reference example, the magnetic ring 5 may be configured as a so-called axial gap type power generation unit, facing the stator 13 across an axial gap.

[0073] 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.

[0074] 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]

[0075] 1...Bearing device, 2...Bearing, 5...Magnetic ring, 6...Seal member 6, 7...Sensing unit, 8...Inner ring (rotating side raceway, stationary side raceway), 9...Outer ring (stationary side raceway, rotating side raceway), 13...Stator, 15...Substrate, 17a...Antenna unit, 19...Stator body, 20...Coil assembly, 21...Stator component, 22...Bobbin (annular component), 23...Coil, 41...Convex part (first engaging part), 42...Recessed part (first engaged part), 43...Claw part (second engaging part), 44...Hole (second engaged part), 45...Resin material (annular component), G...Power generation unit

Claims

1. A bearing device comprising a bearing, a sensing unit, a substrate supporting the sensing unit, and a power generation unit capable of supplying power to the sensing unit, wherein the sensing unit, the substrate, and the power generation unit are housed in the bearing, and the power generation unit has a stator supported on the fixed-side raceway of the bearing and a magnetic ring supported on the rotating-side raceway of the bearing and facing the stator with a radial gap between them, The stator includes a stator body to which the substrate is fixed, and a stator component that supports a coil assembly including a coil wound around an annular component. The annular component is provided with a first engaging portion, and the first engaging portion engages with the first engaged portion of the stator component, A bearing device in which a second engaging portion is provided on the stator component, the second engaging portion engages with a second engaged portion of the stator body, and the second engaged portion is provided at a predetermined phase with respect to the substrate fixing position on the stator body.

2. The bearing device according to claim 1, wherein when the fixed-side raceway is an outer ring, the first engaging portion is a protrusion provided on the outer diameter portion of the annular component, and the first engaged portion is a recess provided on the stator component.

3. A bearing device according to claim 1 or claim 2, wherein the second engaging portion is a claw portion provided on the stator component, and the second engaged portion is a hole provided on the stator body.

4. A bearing device according to claim 1 or claim 2, wherein, when there are multiple locations where the phases of the first engaging portion and the first engaged portion, and the phases of the second engaging portion and the second engaged portion are provided, the respective phases are unequally distributed around the circumference.

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