JP6372306B2 - Rolling bearing device - Google Patents

Description

  The present invention relates to a rolling bearing device having a power generation function.

  Conventionally, for example, there is a technique disclosed in Patent Document 1 as a rotating power generation device using an electret material. This technique includes an electrode substrate and an electret substrate in which an electret material is provided on a counter electrode provided to face the electrode substrate. The power generation is performed by relatively rotating the electrode substrate and the electret substrate around the same axis.

JP 2011-97807 A

However, the prior art disclosed in Patent Document 1 keeps the gap between the electrode substrate and the electret substrate to 50 μm or less via a substantially spherical member. However, since the design is not designed in consideration of axial and radial shaft runout, the inter-substrate gap may become too small or too large, which may reduce the power generation capacity. Further, if the shaft swing width becomes larger than the inter-substrate gap, the electrode substrate and the electret substrate may come into contact with each other and the substrate may be damaged.
Therefore, the present invention has been made paying attention to such an unsolved problem of the prior art, and the electrode substrate and the electret substrate are separated from each other in the axial direction in the thrust direction and the radial direction. An object of the present invention is to provide a rolling bearing with a power generation function capable of maintaining an appropriate gap between substrates.

  [Mode 1] In order to achieve the above object, a rolling bearing device according to mode 1 includes a rolling bearing having a rotating wheel, a stationary wheel, and a rolling element provided between the rotating wheel and the stationary wheel so as to freely roll. , An electret electrode formed of electret material provided on one of the rotating ring of the rolling bearing and the stationary ring side member of the rolling bearing, and the electret on the other of the rotating ring and the stationary ring side member A counter electrode provided so as to be opposed to the electrode, and a circuit for connecting the electret electrode and the counter electrode to a load, and the rolling bearing includes an electret electrode caused by rotational deflection in a radial direction or a thrust direction of the rolling bearing. It was set as the structure which has the rotational shake precision which suppresses the change range of the distance between opposing surfaces with an opposing electrode to 20 micrometers or more and 70 micrometers or less.

With such a configuration, when the rotating wheel is stationary, it is possible to store electricity by electrostatic induction between the facing counter electrode and the electret electrode. On the other hand, when the rotating wheel rotates, the electret electrode rotates and relatively rotates with the electret electrode and the counter electrode facing each other. By this rotational motion, the overlapping area of the opposing surfaces of the counter electrode and the electret electrode changes. Due to this change in the overlapping area, movement of electric charges occurs and electricity can be taken out.
In addition, the rolling bearing is configured to have rotational runout accuracy that suppresses the change range of the distance between the opposed surfaces to 20 μm or more and 70 μm or less.
As a result, it is possible to prevent the generation of rotational resistance due to the influence of the Coulomb force when the distance between the opposing surfaces is less than 20 μm due to the rotational runout of the rolling bearing, damage due to contact, and reduction in the amount of power generation due to the discharge phenomenon. The effect is obtained. In addition, it is possible to prevent an amount of power generation from being reduced due to weakening of electrostatic force when the distance between the opposing surfaces exceeds 70 μm.

[Embodiment 2] Further, in the rolling bearing device of Embodiment 2, the member on the stationary wheel side is a stationary wheel and a housing attached to the stationary wheel with respect to the configuration of Embodiment 1.
That is, either the counter electrode or the electret electrode is provided on either the stationary wheel or the housing attached to the stationary wheel.
Accordingly, for example, when there is no space for providing only one electrode on the bearing side, the rolling bearing device can be configured at a relatively low cost by using the existing bearing as it is by providing the other electrode on the housing. The effect is obtained.

[Embodiment 3] Furthermore, the rolling bearing device of Embodiment 3 is provided with an electret electrode on one end face or peripheral surface of either the rotating wheel or the stationary wheel, with respect to the configuration of Embodiment 2, and either the rotating wheel or the stationary wheel. The counter electrode was provided in the end surface or peripheral surface which opposes an electret electrode among the other end surfaces or peripheral surfaces.
With such a configuration, as the rotating wheel rotates, one of the counter electrode or electret electrode provided on the end surface or peripheral surface of the rotating wheel rotates, and the counter electrode provided on the end surface or peripheral surface of the stationary wheel or The counter electrode and the electret electrode can be relatively rotated while facing the other one of the electret electrodes.
As a result, it is possible to generate power by providing electrodes on the end surfaces or peripheral surfaces of the rotating and stationary wheels of the existing bearing, so that the rolling bearing device can be configured using the existing bearing as it is. It becomes. As a result, there is an effect that the rolling bearing device can be configured at a relatively low cost without causing a bearing design change or the like.

[Embodiment 4] Furthermore, the rolling bearing device of Embodiment 4 is different from the configuration of Embodiment 2 in that either the electret electrode or the counter electrode is provided on the end face or the peripheral surface of the rotating wheel, and the electret electrode or counter electrode of the housing is provided. Either the electret electrode or the counter electrode was provided on the surface facing either one of the electrodes.
If it is such a structure, with rotation of a rotating wheel, one of the counter electrode or electret electrode provided in the end surface or peripheral surface will rotate, and it will face either one of the electret board | substrate or counter electrode of a housing. The counter electrode and the electret electrode can be relatively rotated in a state of facing either the electret electrode or the counter electrode provided on the surface.
As a result, it becomes possible to generate power by providing electrodes on the end face or the peripheral surface of the rotating wheel of the existing bearing and the housing attached to the stationary ring, so that the rolling bearing device can be used by using the existing bearing as it is. The effect that it can comprise is acquired. As a result, there is an effect that the rolling bearing device can be configured at a relatively low cost without causing a bearing design change or the like.

[Embodiment 5] Furthermore, the rolling bearing device of Embodiment 5 is the same as the structure of any one of Embodiments 1 to 4 in that the electret is equivalent to the swing width in the direction intersecting the direction of change in the distance between the opposing surfaces of the rolling bearing. The width in the intersecting direction of either one of the electrode and the counter electrode was made larger than the other.
That is, the width of either the counter electrode or the electret electrode is configured to be longer than the width of the other of the counter electrode or the electret electrode by an amount corresponding to the swing width in the direction intersecting the direction of change in the distance between the counter surfaces.
As a result, it is possible to eliminate or reduce the change in the overlapping area of the opposing surfaces of the electret electrode and the counter electrode due to the shake in the crossing direction, so that an effect of stabilizing the power generation amount can be obtained.

[Mode 6] Further, in the rolling bearing device according to mode 6, the circuit for connecting the electret electrode and the counter electrode to the load with respect to the configuration of any one of modes 1 to 5 includes a slip ring or a conductive seal. It consists of
With such a configuration, one of the counter electrode or the electret electrode that rotates with the rotation of the rotating wheel and the other of the counter electrode or the electret electrode provided on the stationary wheel side member are stopped from rotating. The effect of being able to be electrically connected to the load without being obtained.
[Embodiment 7] Further, in the rolling bearing device of Embodiment 7, the rolling element is made of an insulating material with respect to any one of Embodiments 1 to 6.
That is, since the rolling elements constituting the rolling bearing are made of an insulating material such as ceramics, it is possible to suppress or reduce the occurrence of electrolytic corrosion between the rotating wheel and the stationary wheel side member due to power generation. The effect that it can be obtained.

It is a disassembled perspective view which shows the structural example of 1 A of 1st rolling bearing apparatuses which concern on 1st Embodiment. (A) is a disassembled side view which shows the structural example of 1 A of 1st rolling bearing apparatuses which concern on 1st Embodiment, (b) is an axial sectional view of the radial bearing 2, (c), FIG. 6 is an axial sectional view of the housing 6. It is a fragmentary longitudinal cross-sectional view of 1 A of 1st rolling bearing apparatuses which concern on 1st Embodiment. (A) is a figure which shows the structural example of the electrode substrate 3 which concerns on 1st Embodiment, (b) is a figure which shows the structural example of the electret board | substrate 4 which concerns on 1st Embodiment. (A)-(c) is a fragmentary sectional view for demonstrating the change of the distance L between opposing surfaces by the rotational shake of the electrode substrate 3 which concerns on 1st Embodiment, and the electret board | substrate 4 in the thrust direction. (A)-(c) is a fragmentary sectional view for demonstrating the change of the radial direction by the rotational shake of the radial direction of the electrode substrate 3 and the electret board | substrate 4 which concerns on 1st Embodiment. It is a fragmentary longitudinal cross-section which shows the structural example of the 2nd rolling bearing apparatus 1B which concerns on the modification of 1st Embodiment. (A) is a decomposition | disassembly side view which shows the structural example of 1C of 3rd rolling bearing apparatuses which concern on 2nd Embodiment, (b) is an axial sectional view of the radial bearing 2C, (c) is It is an axial sectional view of the housing 6C. It is a fragmentary longitudinal cross-section which shows the structural example of 1C of 3rd rolling bearing apparatuses which concern on 2nd Embodiment. (A) is a figure showing the example of composition of electrode board 3C concerning a 2nd embodiment, (b) is the figure showing the example of composition of electret board 4C concerning a 2nd embodiment, (c) FIG. 4 is a view showing a configuration of arrangement of an electrode substrate 3C and an electret substrate 4C according to the second embodiment. (A) is a side view which shows the structural example of 4th rolling bearing apparatus 1D which concerns on 3rd Embodiment, (b) is an axial sectional view of radial bearing 2D, (c) is a housing. FIG. 6 is an axial cross-sectional view of FIG. It is a fragmentary longitudinal cross-section which shows the structural example of 4th rolling bearing apparatus 1D which concerns on 3rd Embodiment. (A) is a figure which shows the structural example of electrode substrate 3D which concerns on 3rd Embodiment, (b) is a figure which shows the structural example of electret board | substrate 4D which concerns on 3rd Embodiment, (c) FIG. 5 is a view showing an arrangement configuration of an electrode substrate 3D and an electret substrate 4D according to the third embodiment. It is a fragmentary longitudinal cross-section which shows the structural example of the 5th rolling bearing apparatus 1E of 4th Embodiment. It is a fragmentary longitudinal cross-section which shows the structural example of the 6th rolling bearing apparatus 1F which concerns on the modification of 4th Embodiment. It is a fragmentary longitudinal cross-section which shows the example of a structure of 7th rolling bearing apparatus 1G of 5th Embodiment. (A)-(c) is a figure which shows the modification of the attachment method of the housing to a rolling bearing.

(First embodiment)
(Constitution)
As shown in FIG. 1 and FIG. 2A, a first rolling bearing device 1A according to the first embodiment includes a radial bearing 2 that is a rolling bearing configured to mainly receive a radial load, and an electrode. A substrate 3, an electret substrate 4, a circuit substrate 5, and a housing 6 are included.
The first rolling bearing device 1A has an interval (the distance between the electrode substrate 3 and the electret substrate 4 designed in advance when the components indicated by reference numerals 2 to 6 in FIGS. 1 and 2A are assembled. It is configured to face each other with an air gap). Then, the radial bearing 2 is rotated, and the electrode substrate 3 and the electret substrate 4 are configured to generate power by relatively rotating while facing each other.

The radial bearing 2 can freely roll between an outer ring 20 as a stationary ring, an inner ring 21 as a rotating ring, and an outer ring 20 and an inner ring 21 as shown in the axial sectional views of FIGS. And a spherical rolling element 22 provided on the surface.
In the first embodiment, the radial bearing 2 is constituted by a ball bearing having a spherical shape of the rolling element 22. However, the shape of the rolling element 22 is not limited to this, and the shape of the rolling element 22 is a conical shape, a cylindrical shape, or a needle shape. Alternatively, it may be composed of a roller bearing such as a barrel. Moreover, the dashed-dotted line in Fig.2 (a) and FIG. 3 is a line which shows the axial direction of the rotating shaft (not shown) which 1A of 1st rolling bearing apparatuses support.

Further, as shown in FIGS. 2A and 3, the inner ring 21 is provided with an annular protruding portion 21 p that protrudes in the axial direction at an end portion on the inner peripheral surface side of the end surface on the housing 6 side.
Moreover, in 1st Embodiment, in order to prevent generation | occurrence | production of the electric corrosion by the electrical potential difference of the inner ring | wheel 21 and the outer ring | wheel 20 at the time of electric power generation, the rolling element 22 is comprised from insulating materials, such as ceramics, for example.
The circuit board 5 has a configuration in which a load 50 is provided on one surface of an annular substrate and the other surface is fixed to the housing 6. The load 50 includes, for example, a sensor that measures the rotational speed, rotational direction, temperature, and the like of the radial bearing 2 and its peripheral circuits. Moreover, it is good also as a structure which provides the storage battery which accumulate | stores the produced | generated electricity on one side of the circuit board 5, and supplies electric power to load 50, such as a sensor, via this storage battery.

As shown in the axial cross-sectional view of FIG. 2 (c), the housing 6 includes an annular bottom 60, and a cylindrical protrusion 61 protruding in the axial direction from an outer diameter side end of the bottom 60. It is comprised from the attachment nail | claw part 62 formed by protruding from the front-end | tip part of the protrusion part 61 to an inner diameter side.
As shown in FIGS. 2A and 3, an attachment groove 20 d for attaching the housing 6 to the outer ring 20 is formed at a position closer to the housing 6 than the rolling elements 22 on the outer peripheral surface of the outer ring 20.
With this configuration, the housing 6 is attached to the outer ring 20 by fitting the attachment claw portion 62 of the housing 6 into the attachment groove 20 d of the outer ring 20.

Further, as shown in FIG. 3, in the first rolling bearing device 1A, the electret board 4 is fixed to the end face of the inner ring 21 on the housing 6 side by a conventional fixing method such as fitting, adhesion, or fastening. . As shown in FIG. 3, the electrode substrate 3 is fixed to a position facing the electret substrate 4 on the bottom 60 of the housing 6 by a conventional fixing method such as adhesion or fastening. The outer ring 20 is fixedly supported via the housing 6.
Here, in the first rolling bearing device 1A, the distance between the end surface of the inner ring 21 on the housing 6 side and the position of the bottom portion 60 facing the electret substrate 4 is arranged between the electrode substrate 3 and the electret substrate 4. In this case, the counter electrode 31 and the ELC film 41b are configured to face each other with a previously designed interval (air gap).
The electrode substrate 3 may be fixed to the end surface of the inner ring 21 on the housing 6 side, and the electret substrate 4 may be fixed to a position facing the electrode substrate 3 in the bottom portion 60.

Next, detailed configurations of the electrode substrate 3 and the electret substrate 4 will be described.
As shown in the upper diagram of FIG. 4A, the electrode substrate 3 has a plurality of counter electrodes provided on the one surface of an annular thin substrate 30 at equal intervals along the circumferential direction. 31 is provided. As shown in the lower diagram in FIG. 4A (cross-sectional view taken along the line AA in FIG. 4A), the counter electrode 31 is formed on one surface of the substrate 30 in the order of, for example, chromium, gold, and chromium. Is formed by vapor deposition.
In addition, as shown in the upper diagram of FIG. 4B, the electret substrate 4 has a plurality of annular plates provided on one surface of the thin plate 40 at equal intervals along the circumferential direction. An electret electrode 41 is provided. As shown in the lower diagram in FIG. 4B (the BB cross-sectional diagram in the upper diagram), the electret electrode 41 is formed on one surface of the substrate 40 in the order of, for example, chromium, gold, and chromium. The electrode 41a is deposited, and an electret material film 41b (hereinafter may be referred to as "ELC film 41b") is formed on the electrode 41a.
Moreover, in order to hold an electric charge in the electret electrode 41, a high voltage is applied to the electret electrode 41 using a corona charging device, for example.

  With the above configuration, the first rolling bearing device 1A can store electricity by electrostatic induction between the facing electrode 31 and the electret electrode 41 facing each other when the inner ring 21 is stationary. . On the other hand, the electret board | substrate 4 rotates because the inner ring | wheel 21 rotates, and the electret board | substrate 4 and the electrode substrate 3 perform a relative rotational motion in the state which faced. By this rotational movement, the overlapping area of the opposing surfaces of the counter electrode 31 and the ELC film 41b changes. Due to the change in the overlapping area, movement of electric charges occurs and electricity can be taken out (power generation).

In addition, as an electret material, it is possible to use polymer materials, such as a fluororesin and a polypropylene, for example. In particular, it is desirable to use CYTOP (registered trademark) manufactured by Asahi Glass Co., Ltd. or Teflon (registered trademark) AF (amorphous fluoropolymer) manufactured by Du Pont, which is a fluororesin suitable for forming a thin film.
Further, as the material of the circuit board 5, the board 30 and the board 40, for example, paper phenol, paper epoxy, glass epoxy, plastic film, glass composite base material in which paper and glass are mixed, or the like can be used. .

Next, the distance L between the opposing surfaces between the counter electrode 31 of the electrode substrate 3 and the ELC film 41b of the electret substrate 4 will be described.
In the first embodiment, the distance L between the opposed electrodes 31 and the ELC film 41b is set to “L = d” when the radial bearing 2 is stationary as shown in FIG. In this case, the distance L between the opposed surfaces is the shortest distance d _min where the distance L between the opposed surfaces shown in FIG. 5B is the shortest due to the rotational vibration of the radial bearing 2 (the vibration in the thrust direction due to the rotation). The distance L between the opposing surfaces shown in 5 (c) varies between the longest distance _dmax and the longest distance _dmax .

  Here, when the distance L between the opposing surfaces is shorter than “20 μm”, the electrode substrate 3 and the electret substrate 4 are pulled against each other due to the influence of the Coulomb force generated between the electrode substrate 3 and the electret substrate 4, and the rotational resistance is reduced. Arise. Further, due to the influence of Coulomb force, the electrode substrate 3 and the electret substrate 4 may come into contact with each other, and either one or both may be damaged. In addition, due to the discharge phenomenon, the electret board 4 may be reduced in the amount of charge and the power generation amount may be reduced. On the other hand, when the distance L between the opposing surfaces is longer than “70 μm”, the electrostatic force is weakened, the amount of charge movement is reduced, and the power generation amount is reduced.

Therefore, in the first embodiment, the shortest distance d _{min of the} distance L between the opposing surfaces due to the vibration in the thrust direction during rotation of the radial bearing 2 is “20 μm ≦ d _min ”, and the longest distance d _max is “d _max ≦ The first rolling bearing device 1 </ b> A is configured from the radial bearing 2 having a rotational runout accuracy of “70 μm”.
For example, when the distance d between the opposing surfaces at rest is “45 μm”, the rotational shake accuracy and the separation in the direction in which the opposing electrode 31 and the ELC film 41 b approach each other with the distance between the opposing surfaces “45 μm” as the center value. The first rolling bearing device 1A is configured by using a radial bearing 2 of a grade in which both the rotational runout accuracy in the direction of rotation is 25 μm or less (that is, the accuracy of the rotational runout width in the thrust direction during rotation is “50 μm” or less). .

In addition, the overlapping area of the opposing surfaces of the counter electrode 31 of the electrode substrate 3 and the ELC film 41 b of the electret substrate 4 also changes due to radial deflection during rotation of the radial bearing 2.
In contrast to the change in the overlap area due to the rotation of the inner ring 21, the unintentional change in the overlap area due to the rotational runout in the radial direction causes the power generation amount to be unstable.
Therefore, in the rolling bearing device 1A of the first embodiment, as shown in FIG. 6A, the radial width of the counter electrode 31 of the electrode substrate 3 is set to be equal to the radial width of the electret substrate 4 by the rotation. The dimension is longer than the width of the ELC film 41b. Here, the direction away from the rotation axis, which is one direction in the radial direction, is the left direction in FIGS. 6A to 6C, and the direction approaching the rotation axis, which is the other direction in the radial direction, is illustrated in FIGS. (C) In the right direction.

That is, as shown in FIG. 6B, the maximum deflection width d1 caused by the leftward deflection of the ELC film 41b and the rightward deflection of the counter electrode 31, and the ELC film 41b as shown in FIG. The radial width of the counter electrode 31 is longer than the radial width of the ELC film 41b by “d1 + d2”, which is the sum of the rightward deflection and the maximum deflection width d2 generated by the counter electrode 31 leftward. Consists of dimensions. Here, the maximum deflection widths d1 and d2 are determined based on, for example, measured values measured by experiments.
With the above configuration, as shown in FIG. 6B, for example, when the electrode substrate 3 swings to the right and the electret substrate 4 swings to the left, the total swing width (deviation width) is Since it becomes d1 or less, the overlapping area does not change. Similarly, as shown in FIG. 6C, for example, when the electrode substrate 3 swings leftward and the electret substrate 4 swings rightward, the total swing width (deviation width) is d2 or less. Therefore, the overlapping area does not change.

Further, as shown in FIG. 3, the first rolling bearing device 1A has a conductive property such as graphite or conductive resin provided so as to seal a gap between the housing 6 and the protruding portion 21p of the inner ring 21. A conductive seal 70 made of material is provided. In addition, the rolling bearing device 1A includes a non-conductive seal 80 formed of a non-conductive material provided so as to seal a gap between ends of the outer ring 20 and the inner ring 21 opposite to the housing 6. It has.
In the first embodiment, the outer ring 20, the inner ring 21 and the housing 6 are made of a conductive metal material. Therefore, the housing 6 and the inner ring 21 are connected via the conductive seal 70 so as to be energized.

1 A of 1st rolling bearing apparatuses are further provided with the wiring 51-53 for connecting the counter electrode 31 of the electrode substrate 3, and the electret electrode 41 of the electret board | substrate 4 with the load 50 provided on the circuit board 5. FIG. ing.
The wiring 51 is a wiring that electrically connects the housing 6 and one end of the power supply end or ground end of the load 50, and the wiring 52 is connected to the other end of the power supply end or ground end of the load 50. This wiring electrically connects the counter electrode 31. The wiring 53 is a wiring that electrically connects the electret electrode 41 and the inner ring 21.

The connection destination of the wiring 51 and the wiring 52 is different depending on the electrification state of the electret electrode 41. For example, when the electret electrode 41 is negatively charged, the wiring 51 is connected to the power supply end, and the wiring 52 is connected. Connect to the ground end. When the electret electrode 41 is positively charged, the connection is reversed.
Accordingly, the electret electrode 41 is energized to one end of the power supply end or ground end of the load 50 via the wiring 53 and the conductive seal 70, and the counter electrode 31 is connected to the power supply end or ground of the load 50 via the wiring 52. Energize the other end of the ends.
Here, in the first embodiment, a circuit for electrically connecting the counter electrode 31 and the electret electrode 41 to the load 50 is configured from the conductive seal 70 and the wirings 51 to 53.

(Operation)
In the first rolling bearing device 1 </ b> A of the first embodiment, the inner ring 21 rotates due to the rotation of a rotating shaft (not shown) supported by the radial bearing 2, and the electret substrate 4 rotates along with this rotation. Thereby, the electrode substrate 3 provided in the housing 6 and the electret substrate 4 provided in the inner ring 21 face each other and relatively rotate around the rotation axis.
Since the counter electrode 31 of the electrode substrate 3 and the ELC film 41b of the electret substrate 4 face each other, the overlapping area of the opposing surfaces changes due to relative rotational movement. As a result, the charge charged in the ELC film 41 b moves, and a current flows through the load 50 through the conductive seal 70 and the wirings 51 to 53.
At this time, the rotational distance in the thrust direction of the radial bearing 2 accompanying the rotation of the inner ring 21 changes the distance L between the opposing surfaces of the opposing electrode 31 and the ELC film 41b, but the first rolling bearing device of the first embodiment. 1A is composed of a radial bearing 2 of a grade having a rotational runout accuracy that suppresses the change range of the distance L between the opposing surfaces within a range of 20 μm or more and 70 μm or less.

As a result, it is possible to prevent the generation of rotational resistance due to the influence of Coulomb force accompanying the approach of the counter electrode 31 and the ELC film 41b to a distance of less than 20 μm, damage due to contact, and a decrease in power generation due to a discharge phenomenon. In addition, it is possible to prevent a decrease in the amount of power generation due to weakening of the electrostatic force accompanying the separation of the counter electrode 31 and the ELC film 41b to a distance farther than 70 μm.
Moreover, the ELC film 41 b moves relative to the counter electrode 31 in the radial direction due to radial deflection of the radial bearing 2 accompanying the rotation of the inner ring 21. However, in the first rolling bearing device 1A of the first embodiment, the radial width of the counter electrode is equal to the sum (d1 + d2) of the maximum deflection width d1 in one direction in the radial direction and the maximum deflection width d2 in the other direction. Is larger than the radial width of the ELC film 41b.
As a result, it is possible to prevent or reduce the change in the overlapping area due to the movement of the counter electrode 31 and the ELC film 41b in the radial direction. As a result, the power generation amount can be stabilized.
Moreover, 1 A of 1st rolling bearing apparatuses of 1st Embodiment comprise the rolling element 22 of the radial bearing 2 from insulating materials, such as ceramics. As a result, it is possible to prevent or reduce the occurrence of electrolytic corrosion due to a potential difference between the outer ring 20 and the inner ring 21 due to power generation.

(Modification of the first embodiment)
(Constitution)
Next, the structure of the 2nd rolling bearing apparatus 1B which concerns on the modification of 1st Embodiment is demonstrated.
In the first rolling bearing device 1A of the first embodiment, the conductive seal 70 is used to electrically connect the counter electrode 31 to one of the power supply end or the ground end of the load 50. In contrast, the second rolling bearing device 1B according to the modification of the first embodiment is different in that it is electrically connected using a slip ring instead of the conductive seal 70. Further, the second rolling bearing device 1B is different from the first rolling bearing device 1A of the first embodiment in that the non-conductive seal 80 is not provided.
Hereinafter, the same components as those of the first rolling bearing device 1A of the first embodiment are denoted by the same reference numerals, description thereof will be omitted as appropriate, and only different portions will be described in detail.

As shown in FIG. 7, in the second rolling bearing device 1 </ b> B, the slip ring 71 that electrically connects the outer ring 20 and the inner ring 21 has rolling elements 22 on the inner peripheral surface of the outer ring 20 and the outer peripheral surface of the inner ring 21. Is also provided at a position on the housing 6 side.
Specifically, as shown in FIG. 7, the slip ring 71 includes a thick fixed electrode 71a formed of an insulating material such as a resin material, one end face of which is fixed to the inner peripheral surface of the outer ring 20, and the fixed And a brush 71b containing a spring element formed of a conductive material such as carbon provided on the other end face of the electrode 71a. The brush 71 b is electrically connected to the outer ring 20 via the wiring 54.

Furthermore, the slip ring 71 has a cylindrical member 71c made of an insulating material such as a ceramic material or a composite resin material having high rigidity, and conductivity such as copper provided on the outer peripheral surface of the cylindrical member 71c. And an electrode ring 71d made of a metal material. The cylindrical member 71c is provided with the inner ring 21 fitted inside. The electrode ring 71 d is electrically connected to the inner ring 21 via the wiring 55.
The brush 71 b presses the electrode ring 71 d that rotates together with the inner ring 21 to electrically connect the outer ring 20 and the inner ring 21. Thereby, the electret electrode 41 and the outer ring 20 are electrically connected via the wiring 53 and the slip ring 71.

Since the outer ring 20 is electrically connected to the housing 6, the electret electrode 41 is connected to the power supply end of the load 50 or the ground via the wiring 53, the inner ring 21, the slip ring 71, the outer ring 20, the housing 6 and the wiring 51. It is electrically connected to one end of the ends.
On the other hand, the counter electrode 31 is electrically connected to the other end of the power supply end or the ground end of the load 50 via the wiring 52.
Here, in the modified example of the first embodiment, a circuit for electrically connecting the counter electrode 31 and the electret electrode 41 to the load 50 is configured from the slip ring 71 and the wirings 51 to 55.

As described above, in the second rolling bearing device 1B, similarly to the first rolling bearing device 1A of the first embodiment, the variation range of the distance L between the opposing surfaces due to the rotational runout in the thrust direction is within a range of 20 μm to 70 μm. It is composed of a radial bearing 2 of a grade having a rotational runout accuracy that is suppressed to a minimum.
As a result, it is possible to prevent the generation of rotational resistance due to the influence of Coulomb force accompanying the approach of the counter electrode 31 and the ELC film 41b to a distance of less than 20 μm, damage due to contact, and a decrease in power generation due to a discharge phenomenon. In addition, it is possible to prevent a decrease in the amount of power generation due to weakening of the electrostatic force accompanying the separation of the counter electrode 31 and the ELC film 41b to a distance farther than 70 μm.

In addition, the second rolling bearing device 1B is an added value of the maximum deflection width d1 in one direction in the radial direction and the maximum deflection width d2 in the other direction, similarly to the first rolling bearing device 1A of the first embodiment. The radial width of the counter electrode is made larger than the radial width of the ELC film 41b by the width of (d1 + d2).
As a result, it is possible to prevent or reduce the change in the overlapping area due to the movement of the counter electrode 31 and the ELC film 41b in the radial direction. As a result, the power generation amount can be stabilized.
In the second rolling bearing device 1B, similarly to the first rolling bearing device 1A of the first embodiment, the rolling elements 22 of the radial bearing 2 are made of an insulating material such as ceramics. As a result, it is possible to prevent or reduce the occurrence of electrolytic corrosion due to a potential difference between the outer ring 20 and the inner ring 21 due to power generation.

(Second Embodiment)
(Constitution)
Next, the configuration of the third rolling bearing device 1C according to the second embodiment will be described.
The third rolling bearing device 1C of the second embodiment is different from the first rolling bearing device 1A of the first embodiment in the configuration and arrangement of the electrode substrate and the electret substrate. In addition, the arrangement configuration of the conductive seal, the shape of the inner ring, the shape of the housing, and the like are different.
Hereinafter, the same components as those in the first rolling bearing device 1A of the first embodiment will be denoted by the same reference numerals, description thereof will be omitted as appropriate, and different components will be described in detail.

As shown in FIGS. 8A and 9, the third rolling bearing device 1C includes a radial bearing 2C, an electrode substrate 3C, an electret substrate 4C, a circuit substrate 5, and a housing 6C. The Moreover, the dashed-dotted line in Fig.8 (a) and FIG. 9 is a line which shows the axial direction of the rotating shaft (not shown) which 1C of 3rd rolling bearing apparatuses support.
The radial bearing 2 </ b> C includes an outer ring 20 as a stationary ring, an inner ring 21 </ b> C as a rotating ring, and a rolling element 22, as shown in the axial sectional view of FIG. 8B. As shown in FIG. 8B, the axial length of the inner ring 21 </ b> C is configured to be longer than the axial length of the outer ring 20. Moreover, the end surface of the one end part of the inner ring 21C in the axial direction and the end face of the one end part of the outer ring 20 in the axial direction are at the same surface position. With this configuration, as shown in FIGS. 8A and 8B, the other end portion of the inner ring 21 </ b> C in the axial direction protrudes from the other end portion of the outer ring 20 in the axial direction.

As shown in the axial cross-sectional view of FIG. 8C, the housing 6C includes an annular bottom 60C and a cylindrical first protrusion 61C that protrudes in the axial direction from the outer diameter side end of the bottom 60C. And a cylindrical second protrusion 63C that protrudes in the axial direction from the inner diameter side end of the bottom 60C and is longer in the axial direction than the first protrusion 61C. Furthermore, the housing 6C includes a mounting claw 62C that is formed to protrude toward the inner diameter side at the tip of the first protrusion 61C.
Here, as shown in FIG. 10A, the electrode substrate 3 </ b> C has a plurality of counter electrodes 31 provided at equal intervals along the circumferential direction on the inner peripheral surface of a cylindrical thin substrate 30 </ b> C. I have.
Further, as shown in FIG. 10B, the electret substrate 4C has a plurality of cylindrically arranged thin plate substrates 40C having a smaller diameter than the substrate 30C and provided at equal intervals along the circumferential direction. An electret electrode 41 is provided. The diameter dimensions of the electrode substrate 3C and the electret substrate 4C are designed such that the distance L between the opposing surfaces of the counter electrode 31 and the ELC film 41b is the distance when the radial bearing 2C is designed in a stationary state.

As shown in FIG. 9, the third rolling bearing device 1 </ b> C includes a cylindrical electret substrate 4 </ b> C that is fitted, bonded, fastened, etc. closer to the housing 6 </ b> C than the rolling element 22 on the outer peripheral surface of the inner ring 21 </ b> C. It is fixed by a conventional fixing method. Further, the cylindrical electrode substrate 3C is fixed to a position facing the electret substrate 4C on the inner peripheral surface of the second projecting portion 63C of the housing 6C by a conventional fixing method such as fitting, bonding, or fastening.
Here, in the case of the third rolling bearing device 1C, when the distance between the second protrusion 63C and the inner ring 21C is provided with the electrode substrate 3C and the electret substrate 4C, the counter electrode 31 and the ELC film 41b However, they are configured to face each other with a predesigned interval (air gap).

The electrode substrate 3C is fixed to the housing 6C side with respect to the rolling element 22 on the outer peripheral surface of the inner ring 21C, and the electret substrate 4C is fixed to a position facing the electrode substrate 3C on the inner peripheral surface of the second protrusion 63C. It is good also as a structure.
With the above configuration, the third rolling bearing device 1C can store electricity between the counter electrode 31 and the electret electrode 41 by electrostatic induction when the inner ring 21C is stationary. On the other hand, the electret substrate 4C is rotated by the rotation of the inner ring 21C, and relatively rotates with the electret substrate 4C and the electrode substrate 3C facing each other. Due to this rotational movement, movement of electric charges occurs and electricity can be taken out (power generation).

Further, as the material of the substrate 30C and the substrate 40C, the same material as that of the substrate 30 and the substrate 40 of the first embodiment can be used.
Next, the distance L between the opposing surfaces between the counter electrode 31 of the electrode substrate 3C and the ELC film 41b of the electret substrate 4C will be described.
In the second embodiment, for the same purpose as in the first embodiment, the third rolling bearing device 1C is provided with a change in the distance L between the opposing surfaces due to the radial runout during the rotation of the radial bearing 2C by “20 μm ≦ d It is composed of a radial bearing 2C of a grade having a rotational runout accuracy that is suppressed to “ _min ” and “d _max ≦ 70 μm”.

In the second embodiment, for the same purpose as in the first embodiment, the width of the counter electrode 31 of the electrode substrate 3C in the thrust direction is equal to the width of the ELC film 41b of the electret substrate 4C by the amount of the swing width in the thrust direction. It has a longer dimension.
Further, as shown in FIG. 9, the third rolling bearing device 1C is made of graphite, conductive resin, or the like provided so as to seal a gap between the second protrusion 63B of the housing 6C and the inner ring 21C. A conductive seal 70C formed of a conductive material is provided. In addition, the third rolling bearing device 1C includes a non-conductive seal 80 provided so as to seal a gap between the outer ring 20 and the inner ring 21C on the side opposite to the housing 6C.

Moreover, in 2nd Embodiment, the outer ring | wheel 20, the inner ring | wheel 21C, and the housing 6C are comprised from the electroconductive metal material. Therefore, the housing 6C and the inner ring 21C are electrically connected via the conductive seal 70C.
The third rolling bearing device 1 </ b> C further includes wirings 51 </ b> C to 52 </ b> C for connecting the counter electrode 31 of the electrode substrate 3 </ b> C and the electret electrode 41 of the electret substrate 4 </ b> C to a load 50 provided on the circuit board 5. ing.
The wiring 51C is a wiring that electrically connects the housing 6C and one end of the power supply end or ground end of the load 50, and the wiring 52C is connected to the other end of the power supply end or ground end of the load 50. This wiring electrically connects the counter electrode 31.

With the conductive seal 70C and the wirings 51C to 52C, the electret electrode 41 is energized with one end of the power supply end or the ground end of the load 50 through the conductive seal 70C and the wiring 51C, and the counter electrode 31 connects the wiring 52C. And the other end of the power supply end or the ground end of the load 50 is energized.
Here, in the second embodiment, a circuit for connecting the counter electrode 31 and the electret electrode 41 to the load 50 is configured from the conductive seal 70C and the wirings 51C to 52C.

(Operation)
In the third rolling bearing device 1C of the second embodiment, the inner ring 21C is rotated by rotating a rotating shaft (not shown) supported by the radial bearing 2C, and the electret substrate 4C is rotated along with this rotation. Thereby, the electret board | substrate 4C provided in the 2nd protrusion part 63C of the housing 6C and the electrode board | substrate 3C provided in the inner ring | wheel 21C perform a rotational motion relatively around a rotating shaft.
Due to this relative rotational movement, the overlapping area of the opposing surfaces changes. As a result, the charge charged in the ELC film 41b moves, and a current flows through the load 50 via the conductive seal 70C and the wirings 51C to 52C.
At this time, the distance L between the opposed surfaces of the opposed electrode 31 and the ELC film 41b changes due to the radial runout of the radial bearing 2C accompanying the rotation of the inner ring 21C, but the third rolling bearing device of the second embodiment. 1C includes a radial bearing 2C of a grade having a rotational runout accuracy that suppresses a change range of the distance L between the opposing surfaces within a range of 20 μm to 70 μm.

As a result, it is possible to prevent the generation of rotational resistance due to the influence of Coulomb force accompanying the approach of the counter electrode 31 and the ELC film 41b to a distance of less than 20 μm, damage due to contact, and a decrease in power generation due to a discharge phenomenon. In addition, it is possible to prevent a decrease in the amount of power generation due to weakening of the electrostatic force accompanying the separation of the counter electrode 31 and the ELC film 41b to a distance farther than 70 μm.
Further, the ELC film 41b moves relative to the counter electrode 31 in the thrust direction due to the vibration in the thrust direction of the radial bearing 2C accompanying the rotation of the inner ring 21C. However, in the third rolling bearing device 1C of the second embodiment, the thrust direction of the counter electrode is equal to the sum of the maximum deflection width d1 in one direction of the thrust direction and the maximum deflection width d2 in the other direction (d1 + d2). Is larger than the width of the ELC film 41b in the thrust direction.
As a result, it is possible to prevent or reduce the change in the overlapping area due to the movement of the counter electrode 31 and the ELC film 41b in the thrust direction. As a result, the power generation amount can be stabilized.
In the third rolling bearing device 1C of the second embodiment, the rolling elements 22 of the radial bearing 2C are made of an insulating material such as ceramics. Thereby, it is possible to prevent or reduce the occurrence of electrolytic corrosion due to a potential difference between the outer ring 20 and the inner ring 21C due to power generation.

(Third embodiment)
(Constitution)
Next, the structure of 4th rolling bearing apparatus 1D which concerns on 3rd Embodiment is demonstrated.
The fourth rolling bearing device 1D of the third embodiment is different from the first and third rolling bearing devices 1A and 1C of the first and second embodiments in the arrangement configuration of the electrode substrate and the electret substrate. . In addition, the arrangement configuration of the conductive seal, the shape of the inner ring, and the like are different.
Hereinafter, the same components as those of the first and third rolling bearing devices 1A and 1C of the first and second embodiments will be denoted by the same reference numerals, and the description thereof will be omitted as appropriate, and different components will be described in detail. To do.

As shown in FIGS. 11A and 12, the fourth rolling bearing device 1 </ b> D includes a radial bearing 2 </ b> D, an electrode substrate 3 </ b> D, an electret substrate 4 </ b> D, a circuit substrate 5, and a housing 6. The Moreover, the dashed-dotted line in Fig.11 (a) and FIG. 12 is a line which shows the axial direction of the rotating shaft (not shown) which 4th rolling bearing apparatus 1D supports.
As shown in the axial sectional view of FIG. 11B and the radial bearing 2D, the radial bearing 2D includes an outer ring 20 as a stationary ring, an inner ring 21C as a rotating ring, a rolling element 22, and a substrate support 23. Consists of including.
The substrate support portion 23 is configured to project in an annular shape on the outer peripheral surface of the inner ring 21D.
Here, as shown in FIG. 13A, the electrode substrate 3D has a plurality of counter electrodes 31 provided at equal intervals along the circumferential direction on the inner peripheral surface of a cylindrical thin plate substrate 30D. I have.

Further, as shown in FIG. 13B, the electret substrate 4D has a plurality of cylindrically arranged thin plate substrates 40D having a smaller diameter than the substrate 30D and provided at equal intervals along the circumferential direction. An electret electrode 41 is provided. The diameter dimensions of the electrode substrate 3D and the electret substrate 4D are designed such that the distance L between the opposing surfaces of the counter electrode 31 and the ELC film 41b is a pre-designed stationary distance of the radial bearing 2D.
Then, in the fourth rolling bearing device 1D, as shown in FIG. 12, the cylindrical electret substrate 4D is fitted, bonded, and fastened to the outer peripheral surface of the substrate support portion 23 provided on the outer peripheral surface of the inner ring 21C. It is fixed by a conventional fixing method such as. Further, the cylindrical electrode substrate 3D is fixed at a position facing the electret substrate 4D on the housing 6 side of the inner circumferential surface of the outer ring 20 by a conventional fixing method such as fitting, bonding, and fastening. ing.

With this arrangement, as shown in FIG. 13 (c), the electret substrate 4D is arranged inside the electrode substrate 3D, and the counter electrode 31 and the ELC film 41b face each other with a predesigned interval (air gap). To do. Further, the electret substrate 4 is disposed near the outer ring 20 by the substrate support portion 23. As a result, the rotational speed can be increased as compared with the case where it is arranged near the inner ring 21C (for example, the outer peripheral surface of the inner ring 21C).
The electrode substrate 3D is fixed to the outer peripheral surface of the substrate support portion 23, and the electret substrate 4D is fixed to a position on the inner peripheral surface of the outer ring 20 facing the electret substrate 4D on the housing 6 side relative to the rolling element 22. It is good.
With the above configuration, the fourth rolling bearing device 1D can store electricity between the counter electrode 31 and the electret electrode 41 by electrostatic induction when the inner ring 21C is stationary. On the other hand, the electret substrate 4D is rotated by the rotation of the inner ring 21C, and relatively rotates with the electret substrate 4D and the electrode substrate 3D facing each other. Due to this rotational movement, movement of electric charges occurs and electricity can be taken out (power generation).

Next, the distance L between the opposing surfaces between the counter electrode 31 of the electrode substrate 3D and the ELC film 41b of the electret substrate 4D will be described.
In the third embodiment as well, in the same manner as in the second embodiment, the fourth rolling bearing device 1D is changed to “20 μm ≦ d _min ” by changing the distance L between the opposing surfaces due to the radial deflection during the rotation of the radial bearing 2D. In addition, the radial bearing 2C is of a grade having a rotational runout accuracy that is suppressed to “d _max ≦ 70 μm”.
Also, in the third embodiment, similarly to the second embodiment, the width in the thrust direction of the counter electrode 31 of the electrode substrate 3D is set to be larger than the width of the ELC film 41b of the electret substrate 4D by the swing width in the thrust direction due to rotation. It has a long dimension.

Furthermore, as shown in FIG. 12, the fourth rolling bearing device 1D has graphite, conductive resin, or the like provided so as to seal a gap between the housing 6 and the end of the inner ring 21C on the housing 6 side. A conductive seal 70D formed of a conductive material is provided. The conductive seal 70 </ b> D is provided on the inner ring 21 </ b> C side whose rotational speed is lower than that of the upper end side of the substrate support portion 23.
In 3rd Embodiment, the outer ring | wheel 20, the inner ring | wheel 21C, the board | substrate support part 23, and the housing 6 are comprised from the electroconductive metal material. Accordingly, the housing 6, the inner ring 21C, and the board support portion 23 are connected to each other through the conductive seal 70D so as to be energized.

The fourth rolling bearing device 1D further includes wirings 56 to 58 for connecting the counter electrode 31 of the electrode substrate 3D and the electret electrode 41 of the electret substrate 4D to a load 50 provided on the circuit board 5. ing.
The wiring 56 is a wiring that electrically connects the counter electrode 31 and one end of the power supply end or the ground end of the load 50, and the wiring 57 is the other end of the power supply end or the ground end of the load 50. And wiring for electrically connecting the housing 6 and the housing 6. The wiring 58 is a wiring that electrically connects the electret electrode 41 and the substrate support portion 23.

The connection destination of the wiring 56 and the wiring 57 is different depending on the electrification state of the electret electrode 41. For example, when the electret electrode 41 is negatively charged, the wiring 56 is connected to the power supply end, and the wiring 57 is connected. Connect to the ground end. When the electret electrode 41 is positively charged, the connection is reversed.
Therefore, the counter electrode 31 is energized to one end of the power supply end or the ground end of the load 50 through the wiring 56 by these wirings 56 to 58. In addition, the electret electrode 41 is energized with the other end of the power supply end or the ground end of the load 50 via the wiring 58, the substrate support 23, the inner ring 21C, the conductive seal 70D, the housing 6 and the wiring 57.
Here, in 3rd Embodiment, the circuit for electrically connecting the counter electrode 31 and the electret electrode 41 with the load 50 is comprised from the electroconductive seal | sticker 70D and wiring 56-58.

(Operation)
In the fourth rolling bearing device 1D of the third embodiment, the inner ring 21C and the substrate support portion 23 are rotated by rotation of a rotating shaft (not shown) supported by the radial bearing 2D, and the electret substrate 4D is rotated along with this rotation. Rotates. Thereby, the electret electrode 41 of the electret board | substrate 4D and the counter electrode 31 of the electrode board | substrate 3D provided in the inner peripheral surface of the outer ring | wheel 20 are relatively rotated around a rotating shaft, facing each other.
Due to this relative rotational movement, the overlapping area of the opposing surfaces changes. As a result, the electric charge charged in the ELC film 41b moves, and a current flows through the load 50 via the conductive seal 70D and the wirings 56 to 58.
At this time, the distance L between the opposing surfaces of the counter electrode 31 and the ELC film 41b changes due to the radial runout of the radial bearing 2D accompanying the rotation of the inner ring 21C, but the fourth rolling bearing device of the third embodiment. 1D is comprised from the radial bearing 2D of the grade which has the rotational runout accuracy which suppresses the change range of the distance L between opposing surfaces in the range of 20 micrometers or more and 70 micrometers or less.

As a result, it is possible to prevent the generation of rotational resistance due to the influence of Coulomb force accompanying the approach of the counter electrode 31 and the ELC film 41b to a distance of less than 20 μm, damage due to contact, and a decrease in power generation due to a discharge phenomenon. In addition, it is possible to prevent a decrease in the amount of power generation due to weakening of the electrostatic force accompanying the separation of the counter electrode 31 and the ELC film 41b to a distance farther than 70 μm.
Further, the ELC film 41b moves relative to the counter electrode 31 in the thrust direction due to the vibration in the thrust direction of the radial bearing 2D accompanying the rotation of the inner ring 21C. However, in the fourth rolling bearing device 1D of the third embodiment, the thrust direction of the counter electrode is equal to the sum of the maximum deflection width d1 in one direction of the thrust direction and the maximum deflection width d2 in the other direction (d1 + d2). Is larger than the width of the ELC film 41b in the thrust direction.

As a result, it is possible to prevent or reduce the change in the overlapping area due to the movement of the counter electrode 31 and the ELC film 41b in the thrust direction. As a result, the power generation amount can be stabilized.
Further, in the fourth rolling bearing device 1 </ b> D of the third embodiment, the electret substrate 4 is disposed near the outer ring 20 by the substrate support portion 23. As a result, the rotational speed can be increased as compared with the case where it is disposed near the inner ring 21C, so that the generated voltage can be increased.
Moreover, 4th rolling bearing apparatus 1D of 3rd Embodiment comprises the rolling element 22 of radial bearing 2D from insulating materials, such as ceramics. Thereby, it is possible to prevent or reduce the occurrence of electrolytic corrosion due to a potential difference between the outer ring 20 and the inner ring 21C due to power generation.

(Fourth embodiment)
(Constitution)
Next, the structure of the 5th rolling bearing device 1E which concerns on 4th Embodiment is demonstrated.
The fifth rolling bearing device 1E according to the fourth embodiment is different from the first to fourth rolling bearing devices 1A to 1D according to the first to third embodiments in that a load in the thrust direction is mainly used instead of the radial bearing. The difference is that it is composed of a thrust bearing which is a rolling bearing received by the motor. In addition, since the rolling bearing is a thrust bearing, the arrangement positions of the electrode substrate and the electret substrate are different.
Hereinafter, the same components as those in the first to fourth rolling bearing devices 1A to 1D of the first to third embodiments are denoted by the same reference numerals, description thereof is omitted as appropriate, and different components are described in detail. To do.

As shown in FIG. 14, the fifth rolling bearing device 1E includes a thrust bearing 9, an electrode substrate 3E, an electret substrate 4E, a circuit substrate 5E, and a housing 6E. In addition, the dashed-dotted line in FIG. 14 is a line which shows the axial direction of the rotating shaft (not shown) which the 5th rolling bearing apparatus 1E supports.
As shown in FIG. 14, the thrust bearing 9 is rotatably provided between a housing washer 90 as a stationary wheel, a shaft washer 91 as a rotating wheel, and the housing washer 90 and the shaft washer 91. The spherical rolling element 92 and a retainer 93 that holds the rolling element 92 in the circumferential direction at substantially equal intervals.
In the fourth embodiment, the thrust bearing 9 is composed of a ball bearing having a spherical shape of the rolling element 92. However, the shape of the rolling element 92 is not limited to this, and the shape of the rolling element 92 is conical, cylindrical, or needle. You may comprise from roller bearings, such as a shape and a barrel shape.

Further, as shown in FIG. 14, the shaft washer 91 is provided with an annular flange portion 91 p that protrudes in a direction orthogonal to the axial direction at the lower end portion on the outer peripheral surface side.
In the fourth embodiment, in order to prevent the occurrence of electrolytic corrosion due to the potential difference between the shaft washer 91 and the housing washer 90 during power generation, the rolling element 92 is made of an insulating material such as ceramics.
Further, as shown in FIG. 14, the circuit board 5E is configured such that a load 50 is provided on the inner peripheral surface of a cylindrical substrate, and the outer peripheral surface is fixed to the housing 6E by a conventional method such as adhesion or fastening. It has become.

In the fifth rolling bearing device 1E, as shown in FIG. 14, the electret substrate 4E is fixed to the outer peripheral surface of the shaft washer 91 by a conventional fixing method such as fitting, bonding, or fastening. Further, as shown in FIG. 14, the electrode substrate 3 </ b> E is fixed to a position facing the electrode substrate 3 </ b> E on the inner peripheral surface of the housing 6 by a conventional fixing method such as adhesion or fastening. The housing washer 90 is fixedly supported via the housing 6E.
With this arrangement, as shown in FIG. 14, the electret substrate 4E is arranged inside the electrode substrate 3E, and the counter electrode 31 and the ELC film 41b face each other with a predesigned interval (air gap).
The electrode substrate 3E may be fixed to the outer peripheral surface of the shaft washer 91, and the electret substrate 4E may be fixed to a position facing the electrode substrate 3E on the inner peripheral surface of the housing 6.

Next, detailed configurations of the electrode substrate 3E and the electret substrate 4E will be described.
In the fourth embodiment, the electrode substrate 3E and the electret substrate 4E have basically the same structure as the electrode substrate 3C and the electret substrate 4C of the second embodiment (see FIG. 10).
That is, the electrode substrate 3E includes a plurality of counter electrodes 31 provided at equal intervals along the circumferential direction on the inner peripheral surface of a cylindrical thin plate substrate 30E.
Moreover, the electret board | substrate 4E is provided with the several electret electrode 41 provided in the circumferential direction at equal intervals on the outer peripheral surface of the board | substrate 40E of the cylindrical thin plate smaller diameter than the board | substrate 30E. The diameter dimension of the electrode substrate 3E and the electret substrate 4E is designed such that the distance L between the opposing surfaces of the counter electrode 31 and the ELC film 41b is the distance when the thrust bearing 9 is designed in a stationary state.

  With the above configuration, the fifth rolling bearing device 1E can store electricity by electrostatic induction between the facing electrode 31 and the electret electrode 41 facing each other when the shaft washer 91 is stationary. It is. On the other hand, the electret substrate 4E is rotated by the rotation of the shaft washer 91, and relatively rotates with the electret substrate 4E and the electrode substrate 3E facing each other. By this rotational movement, the overlapping area of the opposing surfaces of the counter electrode 31 and the ELC film 41b changes. Due to the change in the overlapping area, movement of electric charges occurs and electricity can be taken out (power generation).

In the fourth embodiment, for the same purpose as in the first to third embodiments, the shortest distance d _{min of the} distance L between the opposing surfaces due to radial deflection during rotation of the thrust bearing 9 is “20 μm ≦ d _min. In addition, the fifth rolling bearing device 1E is configured from the thrust bearing 9 having the rotational runout accuracy in which the longest distance d _max is “d _max ≦ 70 μm”.
For example, when the distance d between the opposing surfaces at rest is “45 μm”, the rotational shake accuracy and the separation in the direction in which the opposing electrode 31 and the ELC film 41 b approach each other with the distance between the opposing surfaces “45 μm” as the center value. The fifth rolling bearing device 1E is configured by using a thrust bearing 9 of a grade in which both the rotational runout accuracy in the rotating direction is 25 μm or less (that is, the radial runout accuracy in the radial direction during rotation is “50 μm” or less). .

In addition, the overlapping area of the opposing surfaces of the counter electrode 31 of the electrode substrate 3 and the ELC film 41 b of the electret substrate 4 also varies depending on the thrust direction deflection during rotation of the thrust bearing 9.
In contrast to the change in the overlapping area due to the rotation of the shaft washer 91, the unintentional change in the overlapping area due to the rotational runout in the thrust direction causes the power generation amount to be unstable.
Therefore, in the fifth rolling bearing device 1E of the fourth embodiment, the thrust direction width of the counter electrode 31 of the electrode substrate 3E is changed in the thrust direction due to rotation for the same purpose as in the first to third embodiments. The dimension is longer than the width of the ELC film 41b of the electret substrate 4E by the width.

  Specifically, in FIGS. 6A to 6C of the first embodiment, this is equivalent to the case where the radial direction is replaced with the thrust direction. That is, the maximum deflection width d1 caused by the deflection in one direction (left direction in the figure) of the ELC film 41b and the deflection in the other direction (right direction in the figure) of the counter electrode 31 and the right side of the ELC film 41b. The width in the thrust direction of the counter electrode 31 is longer than the width in the thrust direction of the ELC film 41b by the width “d1 + d2” obtained by adding the maximum deflection width d2 generated by the deflection in the direction and the leftward deflection of the counter electrode 31. It is configured.

Furthermore, as shown in FIG. 14, the fifth rolling bearing device 1E is made of graphite, conductive resin, or the like provided so as to seal a gap between the housing 6E and the flange 91p of the shaft washer 91. A conductive seal 70E formed of a conductive material is provided.
In the fourth embodiment, the housing washer 90, the shaft washer 91, and the housing 6E are made of a conductive metal material. Therefore, the housing 6E and the shaft washer 91 are connected to each other through the conductive seal 70E so as to be energized.
The fifth rolling bearing device 1E further includes wirings 51E to 53E for connecting the counter electrode 31 of the electrode substrate 3E and the electret electrode 41 of the electret substrate 4E to a load 50 provided on the circuit substrate 5E. ing.

The wiring 51E is a wiring that electrically connects the housing 6E and one end of the power supply end or the ground end of the load 50, and the wiring 52E is connected to the other end of the power supply end or the ground end of the load 50. This wiring electrically connects the counter electrode 31. The wiring 53E is a wiring that electrically connects the electret electrode 41 and the shaft washer 91.
The connection destinations of the wiring 51E and the wiring 52E differ depending on the electrification state of the electret electrode 41. For example, when the electret electrode 41 is negatively charged, the wiring 51E is connected to the power supply end, and the wiring 52E is connected. Connect to the ground end. When the electret electrode 41 is positively charged, the connection is reversed.

Therefore, the electret electrode 41 is energized with one end of the power supply end or the ground end of the load 50 through the wiring 53E, the conductive seal 70E, the housing 6E, and the wiring 51E by these wirings 51E to 53E. The other end of the power supply end or the ground end of the load 50 is energized via the wiring 52E.
Here, in 4th Embodiment, the circuit for electrically connecting the counter electrode 31 and the electret electrode 41 with the load 50 is comprised from the electroconductive seal | sticker 70E and wiring 51E-53E.

(Operation)
In the fifth rolling bearing device 1E of the fourth embodiment, the shaft raceway 91 rotates when the rotating shaft (not shown) supported by the thrust bearing 9 rotates, and the electret substrate 4E rotates with this rotation. . Thereby, the electret electrode 41 of the electret board | substrate 4E and the counter electrode 31 of the electrode board | substrate 3 provided in the inner peripheral surface of the housing 6E are relatively rotated around the rotation axis while facing each other.
Due to this relative rotational movement, the overlapping area of the opposing surfaces changes. As a result, the electric charge charged in the ELC film 41b moves, and a current flows through the load 50 via the conductive seal 70E and the wirings 51E to 53E.
At this time, the radial displacement of the thrust bearing 9 accompanying the rotation of the axial washer 91 changes the distance L between the opposed surfaces of the opposed electrode 31 and the ELC film 41b, but the fifth rolling of the fourth embodiment. The bearing device 1E is composed of a thrust bearing 9 of a grade having a rotational runout accuracy that suppresses the change range of the distance L between the opposing surfaces within a range of 20 μm to 70 μm.

As a result, it is possible to prevent the generation of rotational resistance due to the influence of Coulomb force accompanying the approach of the counter electrode 31 and the ELC film 41b to a distance of less than 20 μm, damage due to contact, and a decrease in power generation due to a discharge phenomenon. In addition, it is possible to prevent a decrease in the amount of power generation due to weakening of the electrostatic force accompanying the separation of the counter electrode 31 and the ELC film 41b to a distance farther than 70 μm.
Further, the ELC film 41 b moves relative to the counter electrode 31 in the radial direction due to the thrust direction deflection of the thrust bearing 9 accompanying the rotation of the shaft washer 91. However, in the fifth rolling bearing device 1E of the fourth embodiment, the thrust of the counter electrode 31 is equal to the added value (d1 + d2) of the maximum deflection width d1 in one direction and the maximum deflection width d2 in the other direction. The width in the direction is configured to be larger than the width in the thrust direction of the ELC film 41b.
As a result, it is possible to prevent or reduce the change in the overlapping area due to the movement of the counter electrode 31 and the ELC film 41b in the thrust direction. As a result, the power generation amount can be stabilized.
In the fifth rolling bearing device 1E of the fourth embodiment, the rolling elements 92 of the thrust bearing 9 are made of an insulating material such as ceramics. As a result, it is possible to prevent or reduce the occurrence of electrolytic corrosion due to the potential difference between the housing washer 90 and the shaft washer 91 due to power generation.

(Modification of the fourth embodiment)
(Constitution)
Next, the structure of the 6th rolling bearing apparatus 1F which concerns on the modification of 4th Embodiment is demonstrated.
The fifth rolling bearing device 1E of the fourth embodiment uses the conductive seal 70E to electrically connect the electret electrode 41 to one of the power supply end or the ground end of the load 50. In contrast, the sixth rolling bearing device 1F according to the modification of the fourth embodiment is different in that it is electrically connected using a slip ring instead of the conductive seal 70E.
Hereinafter, the same components as those of the fifth rolling bearing device 1E of the fourth embodiment are denoted by the same reference numerals, and the description thereof will be omitted as appropriate, and only different portions will be described in detail.
As shown in FIG. 15, the sixth rolling bearing device 1 </ b> F includes a thrust bearing 9 </ b> F, an electrode substrate 3 </ b> E, an electret substrate 4 </ b> E, a circuit substrate 5 </ b> E, a housing 6 </ b> E, and a slip ring 72. .

As shown in FIG. 15, the thrust bearing 9F has a housing washer 90F and a shaft compared to the housing washer 90 and the shaft washer 91 of the thrust bearing 9E of the fourth embodiment in order to provide the slip ring 72. The radial dimension of the washer 91F is long on the housing 6E side.
That is, in the sixth rolling bearing device 1F, as shown in FIG. 15, the slip ring 72 that electrically connects the housing washer 90F and the shaft washer 91F has the lower end surface of the housing washer 90F and the shaft washer. The upper end surface of 91F is provided at a position closer to the housing 6E than the rolling element 92.

As shown in FIG. 15, the slip ring 72 includes a thick fixed electrode 72a formed of an insulating material such as a resin material, one end surface of which is fixed to the lower end surface of the housing washer 90F, and the fixed electrode 72a. And a brush 72b provided with a spring element formed of a conductive material such as carbon provided on the other end face. Further, the brush 72b is electrically connected to the housing washer 90F via the wiring 54F.
Further, the slip ring 72 is made of a cylindrical member 72c made of an insulating material such as a ceramic material or a composite resin material, and a conductive metal material such as copper provided on the upper end surface of the cylindrical member 72c. An electrode ring 72d. The cylindrical member 72c is provided along the circumferential direction at the upper end of the shaft washer 91F. The electrode ring 72d is electrically connected to the shaft washer 91F via the wiring 55F.

The brush 72b presses the electrode ring 72d that rotates together with the shaft washer 91F to electrically connect the housing washer 90F and the shaft washer 91F. Thus, the electret electrode 41 and the housing washer 90F are electrically connected via the wiring 53E and the slip ring 72.
Since the housing washer 90F is electrically connected to the housing 6E, the electret electrode 41 is connected to the load 50 via the wiring 53E, the shaft washer 91F, the slip ring 72, the housing washer 90F, the housing 6E, and the wiring 51E. Is electrically connected to one end of the power supply end or the ground end.

On the other hand, the counter electrode 31 is electrically connected to the other end of the power supply end or the ground end of the load 50 via the wiring 52E.
Here, in the modification of the fourth embodiment, a circuit for electrically connecting the counter electrode 31 and the electret electrode 41 to the load 50 from the slip ring 72, the wires 51E to 53E, and the wires 54F to 55F. Is configured.
As described above, in the sixth rolling bearing device 1F, similarly to the fifth rolling bearing device 1E of the fourth embodiment, the variation range of the distance L between the opposing surfaces due to the radial runout is in the range of 20 μm or more and 70 μm or less. The thrust bearing 9F is of a grade having a rotational runout accuracy that is suppressed to a minimum.

As a result, it is possible to prevent the generation of rotational resistance due to the influence of Coulomb force accompanying the approach of the counter electrode 31 and the ELC film 41b to a distance of less than 20 μm, damage due to contact, and a decrease in power generation due to a discharge phenomenon. In addition, it is possible to prevent a decrease in the amount of power generation due to weakening of the electrostatic force accompanying the separation of the counter electrode 31 and the ELC film 41b to a distance farther than 70 μm.
In addition, the sixth rolling bearing device 1F is an addition value of the maximum deflection width d1 in one direction of the thrust direction and the maximum deflection width d2 in the other direction, similarly to the fifth rolling bearing device 1E of the fourth embodiment. The width in the thrust direction of the counter electrode 31 is made larger than the width in the thrust direction of the ELC film 41b by the width of (d1 + d2).

As a result, it is possible to prevent or reduce the change in the overlapping area due to the movement of the counter electrode 31 and the ELC film 41b in the thrust direction. As a result, the power generation amount can be stabilized.
Further, in the sixth rolling bearing device 1F, the rolling element 92 of the thrust bearing 9F is made of an insulating material such as ceramics, similarly to the fifth rolling bearing device 1E of the fourth embodiment. As a result, it is possible to prevent or reduce the occurrence of electrolytic corrosion due to the potential difference between the housing washer 90F and the shaft washer 91F due to power generation.

(Fifth embodiment)
(Constitution)
Next, the structure of the seventh rolling bearing device 1G according to the fifth embodiment will be described.
The seventh rolling bearing device 1G of the fifth embodiment differs from the fifth rolling bearing device 1E of the fourth embodiment in the configuration and arrangement of the electrode substrate and the electret substrate. In addition, the arrangement configuration of the conductive seal, the shape of the housing washer, the shape of the axial washer, the shape of the housing, and the like are different.
Hereinafter, the same components as those of the fifth rolling bearing device 1E according to the fourth embodiment will be denoted by the same reference numerals, description thereof will be omitted as appropriate, and different components will be described in detail.

As shown in FIG. 16, the seventh rolling bearing device 1G includes a thrust bearing 9G, an electrode substrate 3G, an electret substrate 4G, a circuit substrate 5G, and a housing 6G. Moreover, the dashed-dotted line in FIG. 16 is a line which shows the axial direction of the rotating shaft (not shown) which the 7th rolling bearing apparatus 1G supports.
As shown in FIG. 16, the thrust bearing 9G includes a housing washer 90G as a stationary wheel, a shaft washer 91G as a rotating wheel, a rolling element 92, a cage 93, and a substrate support 94. Composed.
As shown in FIG. 16, the radial length of the axial washer 91G is configured to be longer on the housing 6G side than the radial length of the housing washer 90G. The inner peripheral surface of the shaft washer 91G and the inner peripheral surface of the housing washer 90G are at the same surface position. With this configuration, as shown in FIG. 16, the outer periphery of the shaft washer 91G protrudes from the outer periphery of the housing washer 90G.

The substrate support portion 94 is configured to project in a cylindrical shape along the circumferential direction on the upper end surface on the outer peripheral surface side of the shaft washer 91G.
Further, as shown in FIG. 16, the circuit board 5G has a structure in which a load 50 is provided on the inner peripheral surface of a cylindrical substrate, and the outer peripheral surface is fixed to the housing 6G by a known method such as adhesion or fastening. It has become.
In the seventh rolling bearing device 1G, as shown in FIG. 16, the electret substrate 4G is fixed to the upper end surface of the substrate support portion 94 by a conventional fixing method such as adhesion or fastening. Further, the electrode substrate 3G is fixed to a position facing the electret substrate 4G on the lower end surface on the outer peripheral surface side of the housing washer 90G by a conventional fixing method such as fitting, bonding, and fastening.

Here, in the seventh rolling bearing device 1G, the distance between the lower end surface of the housing washer 90G and the upper end surface of the substrate support 94 is opposed when the electrode substrate 3G and the electret substrate 4G are disposed. The electrode 31 and the ELC film 41b are configured to face each other with a previously designed interval (air gap). Moreover, the electret board | substrate 4G is arrange | positioned by the board | substrate support part 94 near the housing track washer 90G. As a result, the rotational speed can be increased as compared with the case where the shaft washer 91G is disposed near (for example, the upper end surface).
The electrode substrate 3G may be fixed to the upper end surface of the substrate support portion 94, and the electret substrate 4G may be fixed to a position facing the electrode substrate 3G on the lower end surface on the outer peripheral surface side of the housing washer 90G.

Next, detailed configurations of the electrode substrate 3G and the electret substrate 4G will be described.
In the fifth embodiment, the electrode substrate 3G and the electret substrate 4G have basically the same structure as the electrode substrate 3 and the electret substrate 4 of the first embodiment (see FIG. 4).
That is, the electrode substrate 3G includes a plurality of counter electrodes 31 provided at equal intervals along the circumferential direction on one surface of an annular thin substrate 30G.
Moreover, the electret board | substrate 4G is provided with the several electret electrode 41 provided in the circumferential direction at equal intervals on the surface at the side facing the counter electrode 31 of the board | substrate 40G of an annular | circular shaped thin plate.

  With the above configuration, the seventh rolling bearing device 1G can store electricity by electrostatic induction between the facing electrode 31 and the electret electrode 41 facing each other when the shaft washer 91G is stationary. It is. On the other hand, when the shaft washer 91G is rotated, the electret substrate 4G is rotated, and the electret substrate 4G and the electrode substrate 3G are rotated relative to each other. By this rotational movement, the overlapping area of the opposing surfaces of the counter electrode 31 and the ELC film 41b changes. Due to the change in the overlapping area, movement of electric charges occurs and electricity can be taken out (power generation).

Next, the distance L between the opposing surfaces between the counter electrode 31 of the electrode substrate 3G and the ELC film 41b of the electret substrate 4G will be described.
In the fifth embodiment, the shortest distance d _{min of the} distance L between the opposing surfaces due to the vibration in the thrust direction during rotation of the thrust bearing 9G is “20 μm ≦ d _min ” for the same purpose as in the fourth embodiment, and the longest A seventh rolling bearing device 1G is configured from a thrust bearing 9G of a grade having a rotational runout accuracy in which the distance _dmax is “ _dmax ≦ 70 μm”.
In the fifth embodiment, for the same purpose as in the fourth embodiment, the width of the counter electrode 31 of the electrode substrate 3G in the radial direction is set to the width of the ELC film 41b of the electret substrate 4G by an amount corresponding to the radial deflection due to rotation. It has a longer dimension.

Further, as shown in FIG. 16, the seventh rolling bearing device 1G is made of a conductive material such as graphite or a conductive resin provided so as to seal a gap between the housing 6G and the shaft washer 91G. The formed conductive seal 70G is provided. The conductive seal 70G is provided on the shaft washer 91G side whose rotational speed is lower than that of the upper end side of the substrate support portion 94.
In the fifth embodiment, the housing washer 90G, the shaft washer 91G, the substrate support 94, and the housing 6G are made of a conductive metal material. Therefore, the housing 6G and the shaft washer 91G are electrically connected via the conductive seal 70G.

The seventh rolling bearing device 1G further includes wirings 56G to 58G for connecting the counter electrode 31 of the electrode substrate 3G and the electret electrode 41 of the electret substrate 4G to a load 50 provided on the circuit substrate 5G. ing.
The wiring 56G is a wiring that electrically connects the counter electrode 31 and one end of the power supply end or ground end of the load 50, and the wiring 57G is the other end of the power supply end or ground end of the load 50. And wiring for electrically connecting the housing 6G. The wiring 58G is a wiring that electrically connects the electret electrode 41 and the substrate support portion 94.

The connection destination of the wiring 56G and the wiring 57G differs depending on the electrification state of the electret electrode 41. For example, when the electret electrode 41 is negatively charged, the wiring 56G is connected to the power supply end, and the wiring 57G is connected. Connect to the ground end. When the electret electrode 41 is positively charged, the connection is reversed.
Accordingly, the counter electrode 31 is energized with one end of the power supply end or the ground end of the load 50 through the wiring 56G by the wirings 56G to 58G. In addition, the electret electrode 41 is energized with the other end of the power supply end or the ground end of the load 50 via the wiring 58G, the substrate support portion 94, the shaft washer 91G, the conductive seal 70G, and the wiring 57G.
Here, in 5th Embodiment, the circuit for electrically connecting the counter electrode 31 and the electret electrode 41 with the load 50 is comprised from the electroconductive seal | sticker 70G and wiring 56G-58G.

(Operation)
In the seventh rolling bearing device 1G of the fifth embodiment, the rotating shaft (not shown) supported by the thrust bearing 9G rotates to rotate the shaft washer 91G, and the electret substrate 4G rotates with this rotation. . Thereby, the electret board | substrate 4G provided in the upper end surface of the board | substrate support part 94 and the electrode board | substrate 3G provided in the housing track washer 90G relatively rotate around a rotating shaft.
By this relative rotational movement, the overlapping area of the opposing surfaces of the counter electrode 31 and the ELC film 41b changes. As a result, the electric charge charged in the ELC film 41b moves, and a current flows through the load 50 through the conductive seal 70G and the wirings 56G to 58G.
At this time, the rotational distance in the thrust direction of the thrust bearing 9G accompanying the rotation of the shaft washer 91G changes the distance L between the opposed surfaces of the opposed electrode 31 and the ELC film 41b, but the seventh rolling of the fifth embodiment. The bearing device 1G is composed of a thrust bearing 9G of a grade having a rotational runout accuracy that suppresses the change range of the distance L between the opposing surfaces within a range of 20 μm to 70 μm.

As a result, it is possible to prevent the generation of rotational resistance due to the influence of Coulomb force accompanying the approach of the counter electrode 31 and the ELC film 41b to a distance of less than 20 μm, damage due to contact, and a decrease in power generation due to a discharge phenomenon. In addition, it is possible to prevent a decrease in the amount of power generation due to weakening of the electrostatic force accompanying the separation of the counter electrode 31 and the ELC film 41b to a distance farther than 70 μm.
Further, the ELC film 41b moves relative to the counter electrode 31 in the radial direction by the radial deflection of the thrust bearing 9G accompanying the rotation of the shaft washer 91G. However, in the seventh rolling bearing device 1G of the fifth embodiment, the radial width of the counter electrode is equal to the sum (d1 + d2) of the maximum deflection width d1 in one radial direction and the maximum deflection width d2 in the other direction. Is larger than the radial width of the ELC film 41b.

As a result, it is possible to prevent or reduce the change in the overlapping area due to the movement of the counter electrode 31 and the ELC film 41b in the radial direction. As a result, the power generation amount can be stabilized.
Further, in the seventh rolling bearing device 1G of the fifth embodiment, the electret substrate 4G is disposed near the housing washer 90G by the substrate support portion 94. As a result, the rotational speed can be increased as compared with the case where the shaft washer 91G is disposed near, so that the generated voltage can be increased.
In the seventh rolling bearing device 1G of the fifth embodiment, the rolling element 92 of the thrust bearing 9G is made of an insulating material such as ceramics. As a result, it is possible to prevent or reduce the occurrence of electrolytic corrosion due to the potential difference between the housing washer 90G and the shaft washer 91G due to power generation.

(Modification)
(1) In the first to fifth embodiments, the width in the direction (thrust direction or radial direction) orthogonal to the changing direction of the distance L between the opposing surfaces of the counter electrode 31 and the ELC film 41b is larger than the width of the ELC film 41b. Also, the width of the counter electrode 31 is set to be longer by the deflection width due to the rotation. Not limited to this configuration, the width of the ELC film 41b in the orthogonal direction may be longer than the width of the counter electrode 31 by the deflection width due to the rotation.
(2) In the said 1st-5th embodiment, it was set as the structure which provides an electrode board | substrate and an electret board | substrate in either the inner ring | wheel (or axial washer), an outer ring | wheel (or housing washer), and a housing of a rolling bearing. For example, in the case of a thrust bearing, other configurations may be adopted as long as power generation is possible, such as providing an electrode substrate or an electret substrate in a cage.
(3) In the first to fifth embodiments, a configuration using a conductive seal or slip ring to ensure electrical connection between the inner ring (or shaft washer) and the outer ring (or housing washer). It was. Not limited to this configuration, for example, other configurations such as a configuration in which either one of the inner ring (or the shaft washer) or the outer ring (or the housing washer) is provided with a conductive brush that is in contact with either one of the other is possible. It is good.

(4) In the first to third embodiments, the housing is attached to the rolling bearing by fitting the mounting claw provided on the housing into the groove provided on the outer ring of the rolling bearing. Not limited to. For example, it is good also as an attachment structure shown in FIG.17 (c). Specifically, as shown in the sectional view in the axial direction of FIG. 17A, a mounting step portion 24 is provided on the outer peripheral surface of the outer ring of the radial bearing constituting the rolling bearing device. On the other hand, as shown in the axial sectional view of FIG. 17 (b), the housing constituting the rolling bearing device is formed to project in the axial direction at the annular bottom portion 60 and the outer diameter side end portion of the bottom portion 60. The housing 6E is provided with a cylindrical protrusion 61. The housing 6E has a shape in which the mounting claw 62 is eliminated from the housing 6 of the first embodiment. Further, the inner diameter of the housing 6E (projecting portion 61) is configured to be slightly smaller than the outer diameter of the mounting step portion 24. And as shown in FIG.17 (c), the housing 6E is made into the outer peripheral surface of the attachment level | step-difference part 24 with the elastic force of the protrusion part 61 of a slightly small internal diameter by fitting the protrusion part 61 of the housing 6E from the outside. It can be fixedly supported on the outer ring of the rolling bearing.

Each of the above embodiments is a preferable specific example of the present invention, and various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the above description. As long as there is no description, it is not restricted to these forms. In the drawings used in the above description, for convenience of illustration, the vertical and horizontal scales of members or parts are schematic views different from actual ones.
Further, the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.

1A to 1G 1st to 7th rolling bearing device, 2, 2C, 2D radial bearing, 3, 3C to 3G electrode substrate, 4, 4C to 4G electret substrate, 5, 5E, 5G circuit substrate, 6, 6C, 6E , 6G housing, 9, 9F, 9G thrust bearing, 20 outer ring, 21, 21C inner ring, 22, 92 rolling element, 23, 93 substrate support, 31 counter electrode, 41 electret electrode, 50 load, 70, 70C, 70E, 70G conductive seal, 90, 90F, 90G housing washer, 91, 91F, 91G shaft washer

Claims (7)

A rolling bearing having a rotating wheel, a stationary wheel, and a rolling element provided so as to roll between the rotating wheel and the stationary wheel;
An electret electrode formed of an electret material provided on any one of the rotating wheel of the rolling bearing and the stationary wheel side member of the rolling bearing;
A counter electrode provided on either one of the rotating wheel and the stationary wheel side so as to face the electret electrode;
A circuit for connecting the electret electrode and the counter electrode to a load, and
The rolling bearing is configured to have a rotational runout accuracy that suppresses a change range of a distance between the opposed surfaces of the electret electrode and the opposed electrode to 20 μm or more and 70 μm or less due to a rotational runout of the rolling bearing in a radial direction or a thrust direction. Bearing device.   The rolling bearing device according to claim 1, wherein the stationary wheel side member is the stationary wheel and a housing attached to the stationary wheel. Either one of the electret electrode and the counter electrode is provided on an end surface or a peripheral surface of the rotating wheel , and the electret electrode and the counter electrode are disposed on a surface of the housing facing the electret electrode and the counter electrode. The rolling bearing device according to claim 2, wherein either one of the above is provided. The pre Symbol electret electrodes to the rotating wheel and the one end face or circumferential surface either of the stationary ring provided, one of the rotating ring and the end face or circumferential surface and the other of the stationary ring, the end surface facing the electret electrode Or the rolling bearing apparatus of Claim 2 which provided the said counter electrode in the surrounding surface .   The width of the intersecting direction of one of the electret electrode and the counter electrode is made larger than the other by the amount of the swing width in the direction intersecting the direction of change in the distance between the facing surfaces of the rolling bearing. 5. The rolling bearing device according to any one of items 4 to 4.   The rolling bearing device according to any one of claims 1 to 5, wherein a circuit for connecting the electret electrode and the counter electrode to a load includes a slip ring or a conductive seal.   The rolling bearing device according to claim 1, wherein the rolling element is made of an insulating material.

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