JP2004332859A - Rolling bearing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively generate power without using a generator comprising a rotor and a stator even in a small sized and lightweight rolling bearing. <P>SOLUTION: A thermoelectric conversion element 14 having thermoelectric converting function is disposed on at least one of a pair of route members 9 and 10 concentrically disposed between a plurality of rolling elements 11. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rolling bearing having a power generation function.
[0002]
[Prior art]
2. Description of the Related Art A large-sized rolling bearing for supporting a railway vehicle or the like is known to include a generator for generating electric power by using the operation of the bearing (for example, see Patent Document 1). On the other hand, small rolling bearings equipped with such a generator are hardly found on the market. In this case, the generator includes a rotor (rotor) and a stator (stator). One of the reasons is that it is difficult to apply such an existing generator as it is to a small and lightweight rolling bearing because the rotor and the stator are mechanical structural parts and are relatively large and heavy. One of them. However, even if the rolling bearing is small, it should be able to effectively convert and use the heat energy generated by the rotating operation into electric energy. Therefore, a rolling bearing that can effectively use this energy is required.
[0003]
[Patent Document 1]
JP-A-8-225078 (all pages, all drawings)
[0004]
[Problems to be solved by the invention]
SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a relatively small rolling bearing with a power generation function without a rotor or a stator that constitutes a special mechanical part of a generator. An object of the present invention is to provide a rolling bearing provided with:
[0005]
[Means for Solving the Problems]
The rolling bearing according to the present invention is a rolling bearing in which a plurality of rolling elements are interposed between a pair of concentrically arranged fixed and movable side track members, and at least one of the two track members has thermoelectric conversion. A thermoelectric conversion element having a function is provided.
[0006]
According to the rolling bearing according to the present invention, since the thermoelectric conversion element is provided on the track member, for example, a temperature difference between the track member and outside air or a fixed member caused by heat generated by using the rolling bearing. Electric power can be generated in the thermoelectric conversion element by effectively utilizing such factors.
[0007]
In a preferred embodiment, the thermoelectric conversion element and the load are connected so that power generated by a temperature difference acting on the thermoelectric conversion element can be supplied to a load. In this case, since the electric power generated by the thermoelectric conversion element is supplied to the load, the load can be operated. The generated power can be used, for example, to operate a sensor for detecting the temperature or vibration of a rolling bearing as a load, or to operate a measurement system (amplifier, measurement display) capable of displaying the detection result.
[0008]
In a preferred embodiment, the load is an electric device provided in a bearing. In this case, power generated from the thermoelectric conversion element can be supplied to an electric device provided in the bearing, such as a temperature sensor or a vibration sensor of a rolling bearing. Therefore, the thermoelectric conversion element can be used as a driving power supply or an auxiliary power supply for the electric device. As a result, a separate driving power supply is not required or the power supply capacity can be reduced.
[0009]
In a preferred embodiment, the thermoelectric conversion element is mounted on a fixed-side track member of the pair of track members. In this case, the electric power generated by the thermoelectric conversion element can be supplied to the fixed member provided with the fixed-side track member.
[0010]
In a preferred embodiment, the thermoelectric conversion element is provided on a side surface of the fixed-side track member where a bearing load acts. In this case, the thermoelectric conversion element can efficiently generate a thermoelectromotive force by being provided at a side portion where heat is easily generated by the application of a bearing load.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail. 1 to 4 show an embodiment according to the present invention. 1 is a longitudinal sectional side view showing a fan motor provided with a rolling bearing according to the present invention, FIG. 2 is a cross-sectional view showing one half of a rolling bearing as a main part in FIG. 1, and FIG. 3 is a structure of a thermoelectric conversion element. FIG. 4 is a graph showing an example of the relationship between the temperature difference between both surfaces of the thermoelectric conversion element and the thermoelectromotive force.
[0012]
Referring to FIG. 1, a rolling bearing and the like for supporting a rotating shaft of a fan motor are illustrated. Here, 1 indicates the entire fan motor. In this fan motor 1, 2 is a frame, 3 is a propeller, 4 is an electric motor, 5 is a rotor of the electric motor 4, 6 is a stator of the electric motor 4, 7 is a rotation center axis, and 8 is a rotation center axis 7. 4 shows a rolling bearing for rotatably supporting a stator 6. The stator 6 is made of a permanent magnet, and is fixed to the frame 2. The rotor 5 is formed of an armature winding and rotates integrally with the rotation center shaft 7. The rolling bearing 8 is a pair of ball bearings that are disposed at two locations in the axial direction with respect to the rotation center shaft 7.
[0013]
Referring to FIG. 2, rolling bearing 8 includes inner race 9 as one raceway member externally fitted to rotation center shaft 7, outer race 10 as another raceway member internally fitted to stator 6, and rotation center. A plurality of balls 11 arranged at equal intervals in the circumferential direction in an annular space between an inner ring 9 and an outer ring 10 concentrically arranged around the axis of the shaft 7 and these balls 11 as rolling elements are held. It is constituted by a retainer 12 and a seal member 13 that partitions the annular space from the outside at both ends in the axial direction.
[0014]
A thermoelectric conversion element 14 which is a feature of the present embodiment is attached to one side surface of the outer ring 10 of the one rolling bearing 8 in the axial direction by bonding with an adhesive over the entire circumference in the circumferential direction.
[0015]
The thermoelectric conversion element 14 will be described in detail with reference to FIG. 3. The thermoelectric conversion element 14 is configured by alternately arranging two types of thermoelectric conversion portions 17 and 18 of different materials between a pair of opposed ceramic plates 15 and 16. I have. Adjacent two types of thermoelectric conversion parts 17 and 18 are connected to a bonding metal layer 19 formed in layers on the sides of the ceramic plates 15 and 16 facing each other. The bonding metal layer 19 is partitioned for each pair of two adjacent thermoelectric conversion units 17 and 18 and is insulated from the bonding metal layer 19 for the other pair. Further, since the opposing joining metal layers 19 and 19 are arranged so as to be laterally displaced from each other by one thermoelectric converter 17, 18, all the thermoelectric converters 17 are passed through each joining metal layer 19. , 18... Are electrically connected in series. The joining metal layers 19, 19 to which the thermoelectric conversion sections 18, 18 at both ends are joined are electrode sections 20, 20 for taking out electric power to the outside to which lead wires and the like are connected. The thermoelectric converters 17 and 18 use, for example, an alloy material such as sodium cobalt oxide or bismuth tellurium (Bi ₂ Te ₃ ), lead tellurium (PbTe), or silicon germanium (SiGe). In addition, as a material used for such thermoelectric conversion parts 17 and 18, various materials can be used as long as they have a thermoelectric conversion function, and are not particularly limited. In the thermoelectric conversion element 14, when there is a temperature difference between the one ceramic plate 15 side and the other ceramic plate 16 side, a thermoelectromotive force is generated between the electrode portions 20, 20. Therefore, when a circuit is closed between the electrode portions 20, 20, a direct current flows through the circuit. When a load (a resistive load in this example) 21 is provided in the circuit, the power is generated by operating the load 21. Is consumed.
[0016]
The thermoelectric conversion element 14 attached to the rolling bearing 8 has the heat absorbing side of the bonding surface to the outer ring 10. The surface of the thermoelectric conversion element 14 that is exposed to outside air on the side opposite to the adhesive surface is a waste heat or heat radiation side. Therefore, when the electric motor 4 generates heat with the use of the fan motor 1, and the heat generated by the electric motor 4 generates heat, particularly the outer ring 10 of the rolling bearing 8, a temperature difference occurs between the outer ring 10 and air near the outer ring 10, Thus, a temperature difference is generated between the ceramic plate 15 side of the thermoelectric conversion element 14 and the other ceramic plate 16 side, and a thermoelectromotive force is generated. In this case, by providing a closed circuit between the electrode portions 20 of the thermoelectric conversion element 14 via a load 21 such as a resistor, heat is absorbed from the surface on the heat absorbing side, and waste heat or heat radiation is performed. Since waste heat or heat radiation is performed from the side surface, waste heat or heat radiation in the outer ring 10 can be promoted. FIG. 4 is a graph showing the relationship between the temperature difference ° C (horizontal axis) and the thermoelectromotive force mV (vertical axis) on both surfaces of the thermoelectric conversion element 14. In the case of the thermoelectric conversion element 14, it is desirable to use the thermoelectric conversion element 14 in a predetermined temperature difference range, for example, a temperature difference between the heat absorption side and the waste heat side is 100 ° C. to 150 ° C.
[0017]
In addition, if a load 21 such as an LED is interposed between the electrode portions 20 and 20 of the thermoelectric conversion element 14, power generated by thermoelectromotive force can be supplied to the load 21 and the load 21 is driven. be able to. Further, it is also possible to interpose a storage battery or the like between the electrode portions 20 and 20 of the thermoelectric conversion element 14 and charge the storage battery with the power generated by the thermoelectromotive force.
[0018]
Next, another embodiment according to the present invention will be described.
[0019]
FIG. 5 shows an example of the rolling bearing according to the present invention. A thermoelectric conversion element 29 for generating a thermoelectromotive force is provided on one side surface of the outer race 25 of the rolling bearing 22 in the axial direction. An integral sensor housing 30 is annularly provided on the fixed outer ring 25 (in this case, the inner ring 23 is on the rotating side) so as to cover the thermoelectric conversion element 29. The sensor housing 30 is formed of a member having high thermal conductivity, and a surface portion on the waste heat side of the thermoelectric conversion element 29 is in contact with the sensor housing 30. The heat absorbing side surface portion of the thermoelectric conversion element 29 is adhered to the side surface of the outer ring 25. The sensor housing 30 drives a temperature sensor 31 for detecting the temperature of the outer race 25, a vibration sensor 32 for detecting vibration, a rotation sensor 35 for detecting the number of rotations, and a magnetic ring 36, and outputs a detection signal to the outside. A circuit 33 and a battery 34 as a main power supply for each of the sensors 31 and 32 and the circuit 33 are provided. The power supply to the sensors 31, 32, 35, and 36 and the circuit 33 is performed by supplying power from a small battery 34 and supplying power generated from the thermoelectric conversion element 29. A control circuit for the power supply is also provided in the circuit 33. In this case, the thermoelectric conversion element 29 is used as an auxiliary power supply of the battery 34. Here, the circuit 33 and the like correspond to a load to which power is supplied from the thermoelectric conversion element 29. Note that a connector (not shown) that electrically connects to an external device is provided outside the sensor housing 30 in order to output a detection signal of each of the sensors 31, 32, 35, and 36 to the outside as an electric signal. In this case, the output of the detection signal to the external device may be performed wirelessly, that is, by wireless transmission. In particular, in the wireless type that does not use an electrical connection connector, since the power supply to the outside and the system are cut off, the wireless type is more effective as an auxiliary power supply for the battery 34 serving as a main power supply.
[0020]
The thermoelectric conversion element 29 generates a thermoelectromotive force by generating a difference between the temperature of the outer ring 25 due to the heat generated by the rolling bearing 22 and the temperature of the sensor housing 30 due to the use of the rolling bearing 22. 33. Therefore, since more power can be supplied to the circuit 33 than the battery 34 alone, the service life of the battery 34 can be extended, and the battery 34 can be changed to one having a small electromotive force.
[0021]
In addition, as an example of the external device, a display device 37 that indicates what temperature range the rolling bearing 22 is in based on the detection result of the temperature sensor 31 is shown. As a configuration of the display device 37, LEDs of different emission colors are used to display a state in which the rolling bearing 22 is in an appropriate temperature range and a state in which the rolling bearing 22 deviates from the appropriate temperature range to a higher temperature side in each certain temperature range. It may be one that can be displayed.
[0022]
According to the present invention, in order to generate a thermoelectromotive force using the heat generated by the outer ring 39 of the rolling bearing 38, referring to FIG. 6, an annular groove 41 is formed on the side of a fixing member 40 such as a housing into which the outer ring 39 is fitted. The thermoelectric conversion element 42 may be formed in the annular groove 41. In this case, as shown, the heat absorbing side portion of the thermoelectric conversion element 42 is in contact with the outer peripheral surface of the outer ring 39, and the waste heat side portion is in contact with the bottom portion of the annular groove 41.
[0023]
In the above embodiment, the thermoelectric conversion element is provided on the fixed wheel side. However, the thermoelectric conversion element is provided on the rotating wheel side, and the heat absorption side portion and the waste heat side portion of the thermoelectric conversion element provided on the rotating wheel. May be configured to generate a thermoelectromotive force by a temperature difference generated between the two. In this case, a slip ring may be used to extract the thermoelectromotive force to the outside.
[0024]
In the above embodiment, the present invention has been described with respect to a radial bearing, but the present invention may be applied to an axial bearing.
[0025]
Since the rolling bearing of the present invention can perform heat radiation from the rolling bearing in a heated state even in a vacuum in which heat cannot be conducted via air, the thermoelectric conversion element can be used. It can also be used effectively for bearings in various devices such as.
[0026]
The rolling bearing according to the present invention is not limited to a ball bearing, but can be applied to a roller bearing, a needle roller bearing, and the like.
[0027]
【The invention's effect】
According to the rolling bearing according to the present invention, since the thermoelectric conversion element is provided on the track member, for example, a temperature difference between the track member and outside air or a fixed member caused by heat generated by using the rolling bearing. Electric power can be generated in the thermoelectric conversion element by effectively utilizing such factors. By the power generation, heat can be prevented from being accumulated in the rolling bearing.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional side view showing a fan motor including a rolling bearing according to an embodiment of the present invention. FIG. 2 is a cross-sectional view showing one half of a rolling bearing as a main part in FIG. FIG. 4 is a graph showing an example of a relationship between a temperature difference between both surfaces of a thermoelectric conversion element and a thermoelectromotive force. FIG. 5 is a half of a rolling bearing according to another embodiment of the present invention. FIG. 6 is a cross-sectional view showing one half of a rolling bearing according to still another embodiment of the present invention.
9, 10 Track member 11 Rolling element 14 Heat conversion element

Claims (5)

A rolling bearing in which a plurality of rolling elements are arranged and disposed between a pair of track members that are concentrically disposed on a fixed side and a movable side,
A rolling bearing, wherein a thermoelectric conversion element having a thermoelectric conversion function is provided on at least one of the track members. The rolling bearing according to claim 1,
A rolling bearing, wherein the thermoelectric conversion element and the load are connected so that power generated by a temperature difference acting on the thermoelectric conversion element can be supplied to a load. The rolling bearing according to claim 2,
The rolling bearing is characterized in that the load is an electric device provided in the bearing. The rolling bearing according to any one of claims 1 to 3,
The rolling bearing, wherein the thermoelectric conversion element is mounted on a fixed-side track member of the pair of track members. The rolling bearing according to claim 4,
The rolling bearing, wherein the thermoelectric conversion element is provided on a side surface of the fixed-side track member where a bearing load acts.

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