JP7074505B2 - Bearing equipment - Google Patents

Description

The present invention relates to a bearing device, and more particularly to a bearing device capable of accurately detecting a change in the temperature of a rotating wheel of a bearing with a simple configuration.

In Japanese Patent Application Laid-Open No. 2009-68533 (Patent Document 1), in order to accurately and quickly detect an abnormality occurring in a bearing used for a machine tool spindle or the like, the temperature on the fixed side and the temperature on the rotating side of the bearing or the spacer are used. And are measuring. The temperature on the rotating side is measured by a non-contact temperature sensor. In addition to the pyroelectric infrared sensor and thermopile that use infrared rays, a non-contact temperature sensor that uses a ring-shaped temperature measuring body (temperature-sensitive ferrite, etc.) to detect changes in magnetic characteristics has been proposed. There is.

Further, we propose a preload estimation means for estimating the preload of the bearing from the temperature on the fixed side and the temperature on the rotating side of the bearing or the spacer and the rotation speed of the rotating wheel.

Japanese Unexamined Patent Publication No. 2009-68533

Japanese Unexamined Patent Publication No. 2009-68533 discloses a method of utilizing a change in magnetic properties of a ring member as a method of measuring the temperature on the rotating side of a bearing or a seat, but a specific structure of the ring member and a specific structure of the ring member are disclosed. , There is no disclosure about the detection procedure, and there is room for ingenuity.

We also propose a method to estimate the preload from the fixed side temperature and rotation side temperature of the bearing or seat and the rotation speed of the rotating wheel. The rotation speed is measured from the spindle with a rotation sensor, but the rotation sensor Space is required to provide.

An object of the present invention is to provide a bearing device configured to be able to detect a temperature by utilizing magnetic characteristics and to detect a rotation speed without separately providing a rotation sensor.

The present disclosure relates to a bearing device that supports a rotating body with a single bearing or a structure in which a spacer is sandwiched between bearings. Bearings include inner rings, outer rings and rolling elements. The seat includes an outer ring seat and an inner ring seat. The bearing device is provided on the fixed side fixed ring of the inner ring and the outer ring, or the fixed side fixed spacer of the outer ring spacer and the inner ring spacer, and has a magnetic sensor for detecting the magnetic characteristics, and the inner ring and the outer ring. It is provided with a magnetic member which is arranged on the rotating wheel on the rotating side, or the rotating spacer on the rotating side which rotates together with the rotating wheel of the outer ring spacer and the inner ring spacer, and whose magnetic characteristics change depending on the temperature. The magnetic member is magnetized so that the magnetic characteristics detected by the magnetic sensor fluctuate during one rotation of the rotating wheel.

Preferably, the bearing device further includes a signal processing unit that receives the output of the magnetic sensor to detect the state of the bearing, and the signal processing unit calculates the rotation speed and temperature of the rotating wheel based on the output of the magnetic sensor.

Preferably, the magnetic material member is a ring member arranged so that the outer peripheral surface faces the magnetic sensor and is arranged on a rotating wheel or a rotating spacer. In the ring member, the direction of magnetization in the direction outward from the rotation axis of the bearing is alternately different along the rotation direction.

Preferably, the ring member has a first region in which an N pole is formed on the inner peripheral side and an S pole is formed on the outer peripheral side, and a second region in which an N pole is formed on the outer peripheral side and an S pole is formed on the inner peripheral side. The first region and the second region include regions, and the first region and the second region are arranged alternately along the rotation direction.

Preferably, the bearing device further comprises a temperature sensor that measures the temperature of the fixed wheel or fixed spacer, and an anomaly diagnostic unit that diagnoses bearing anomalies based on the output of the temperature sensor and the output of the magnetic sensor.

Preferably, the bearing device further comprises a temperature sensor that measures the temperature of the fixed wheel or fixed spacer, and a preload load estimator that estimates the preload of the bearing based on the output of the temperature sensor and the output of the magnetic sensor. ..

Preferably, the bearing device further comprises a communication unit that wirelessly communicates the information measured by the magnetic sensor.

According to the bearing device of the present disclosure, by arranging one ring member, it is possible to simultaneously detect the temperature and the rotation speed with a simple configuration.

It is a figure which shows the state which incorporated the bearing device of Embodiment 1 into a machine tool spindle. It is sectional drawing which shows the cross section orthogonal to the rotation axis of a ring member. It is sectional drawing of the ring member in the section III-III of FIG. It is a figure which shows the relationship between the rotation angle of a 1-pole pair of ring members, and the magnetic flux density. It is sectional drawing which shows the cross section orthogonal to the rotation axis of the modification of a ring member. It is sectional drawing of the modification of the ring member in the VI-VI cross section of FIG. It is a figure which shows the relationship between the rotation angle of the ring member of a 4-pole pair, and the magnetic flux density. It is a block diagram which shows the structure of the circuit which receives the signal of a magnetic sensor 17. It is a flowchart for demonstrating the 1st example of the abnormality determination processing executed by an abnormality determination part. It is a flowchart for demonstrating the 2nd example of the abnormality determination processing executed by the abnormality determination part. It is a figure which shows the 1st modification of a bearing device. It is a figure which shows the 2nd modification of a bearing device. It is a figure which shows the structure of the bearing device of Embodiment 2. It is a block diagram which shows the structure which performs transmission and reception wirelessly.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding parts will be given the same reference number, and the explanation will not be repeated.

[Embodiment 1]
FIG. 1 is a diagram showing a state in which the bearing device of the first embodiment is incorporated in the machine tool spindle. The bearing device 50 supports a rotating body (spindle 10) by a single bearing or a structure in which a spacer is sandwiched between bearings.

In the example shown in FIG. 1, the bearing device 50 includes a bearing 1 and a spacer 20 and has a structure in which the spacer 20 is sandwiched between the two bearings 1 and rotatably supports the machine tool spindle 10. The bearing 1 includes an inner ring 2, an outer ring 3, a rolling element 4, and a cage 5. The spacer 20 includes an outer ring spacer 7 and an inner ring spacer 6.

The bearing device 50 further includes a magnetic sensor 17 and a ring member 18 in addition to the bearing 1 and the spacer 20. The ring member 18 is a ring-shaped magnetic member arranged around the main shaft. The magnetic sensor 17 is provided on the fixed spacer on the fixed side of the outer ring spacer 7 and the inner ring spacer 6 and detects the magnetic characteristics. The ring member 18 is a magnet magnetized with a magnetic material whose magnetic characteristics change depending on the temperature, and is arranged on the rotating spacer on the rotating side of the outer ring spacer 7 and the inner ring spacer 6. The ring member 18 is magnetized so that the magnetic characteristics (for example, magnetic flux density) detected by the magnetic sensor 17 fluctuate during one rotation of the rotating wheel. The ring member 18 is arranged so that the outer peripheral surface faces the magnetic sensor 17.

In FIG. 1, the bearing 1 constitutes a rolling bearing including an inner ring 2, an outer ring 3, a rolling element 4, and a cage 5, and an inner ring spacer 6 and an outer ring spacer 7 are inserted between the two rolling bearings. Has been done. The machine spindle 10 is inserted into the inner diameter portion 8 and the inner ring spacer inner diameter portion 9 of the inner ring 2, the outer diameter portion 11 and the outer ring spacer outer diameter portion 12 of the outer ring 3 are inserted into the housing 13, and the machine spindle 10 rotates. Supports.

The spacer and the bearing are integrated, the magnetic sensor 17 is provided on the fixed ring on the fixed side of the inner ring 2 and the outer ring 3, and the ring member 18 is arranged on the rotating wheel on the rotating side of the inner ring 2 and the outer ring 3. You may try to do it. A magnetic sensor may be arranged on a fixed wheel with respect to a single bearing, and a magnet on which a magnetic material is magnetized may be arranged on a rotating wheel. Further, the magnet does not necessarily have to be ring-shaped as long as it is magnetized so that the magnetic characteristics (for example, magnetic flux density) detected by the magnetic sensor 17 fluctuates during one rotation of the rotating wheel. For example, a magnet may be attached to a part of the seat.

FIG. 2 is a cross-sectional view showing a cross section orthogonal to the rotation axis of the ring member. FIG. 3 is a cross-sectional view of the ring member in the section III-III of FIG. With reference to FIGS. 2 and 3, the ring member 18 has a first region A1 in which an N pole is formed on the outer peripheral side and an S pole is formed on the inner peripheral side, and an S pole is formed on the outer peripheral side and is on the inner peripheral side. Includes a second region A2 on which the north pole is formed. The first region A1 and the second region A2 are alternately arranged along the rotation direction R.

In the first region A1, the direction of magnetization in the direction from the rotation axis O to the outside is S → N, and in the second region A2, the direction of magnetization in the direction from the rotation axis O to the outside is N → S.

FIG. 4 is a diagram showing the relationship between the rotation angle and the magnetic flux density of the one-pole pair of ring members shown in FIGS. 2 and 3. Since the magnetic flux density of the magnet constituting the ring member 18 changes with a change in temperature, the magnetic sensor 17 can measure the change in the magnetic flux density and calculate the temperature. For example, when a ferritic rubber magnet is used as the ring member 18, the temperature coefficient is about −0.18% / ° C., and the magnetic flux density decreases as the temperature rises.

For example, in a radiation thermometer using infrared rays, if the emissivity of infrared rays of the object to be measured is small, the measurement accuracy will be affected. Hard to receive.

In FIG. 1, the magnetized ring member 18 is attached to the outer peripheral surface 16 of the inner ring spacer 6 and the magnetic sensor 17 is arranged so as to face the outer ring spacer 7, and the magnetic characteristics of the ring member 18 are changed. Is being measured. If an analog output type is used as the magnetic sensor 17, a sinusoidal output corresponding to a change in magnetic flux density can be obtained as shown in FIG.

In a state where the ring member 18 in which the magnetic poles shown in FIGS. 2 and 3 are magnetized to one pole pair is rotated, the output of the magnetic sensor 17 obtains a sinusoidal waveform with one cycle per rotation. Since the magnetic flux density changes depending on the temperature, the change in the magnetic flux density appears as the change in the amplitude.

By smoothing this waveform after full-wave rectification or obtaining the average value of peak values, it is possible to calculate a characteristic value representing a change in amplitude. If the relationship between the change in amplitude and the temperature is acquired in advance by a test or the like, the temperature can be calculated. Further, the rotation speed can be calculated by measuring how many times the peak of the waveform of the magnetic sensor 17 occurs per unit time.

In addition to the method of detecting the amplitude of the output waveform of the magnetic sensor 17 and converting it into temperature, the output signal of the magnetic sensor 17 may be converted into a displacement signal that has been electrically smoothed. When used for a spindle of a machine tool, it rotates at high speed, so that it can be easily detected by smoothing the signal of the magnetic sensor 17.

That is, the ring members 18 and 18A are magnetized so that the S poles and N poles are alternately arranged on the outer peripheral surfaces of the ring members 18 and 18A, and the magnetic flux density is measured by the magnetic sensor 17 to measure the S poles and N poles. The change in polar polarity appears as an amplitude. The rotation speed can be calculated by counting the wave number per hour. Then, the amplitude of the waveform HT at a higher temperature is smaller than the amplitude of the waveform LT at a lower temperature. Therefore, the temperature can be measured by observing the amplitude.

That is, if the ring member 18 magnetized so that the S pole and the N pole are paired is incorporated in the bearing 1 or the spacer 20 and the magnetic flux density is measured by the magnetic sensor 17, the temperature and the rotation speed are calculated by one sensor. can do.

In the example shown in FIGS. 2 and 3, the number of pole pairs is 2, but as shown in FIGS. 5 and 6, if the number of pole pairs of S pole and N pole is increased, the smoothing error after rectification is reduced and the detection is performed. This is preferable because it improves accuracy.

FIG. 5 is a cross-sectional view showing a cross section orthogonal to the rotation axis of a modified example of the ring member. FIG. 6 is a cross-sectional view of a modified example of the ring member in the VI-VI cross section of FIG. With reference to FIGS. 5 and 6, the ring member 18A has first regions A11, A13, A15, A17 in which an N pole is formed on the outer peripheral side and an S pole is formed on the inner peripheral side, and an S pole on the outer peripheral side. Includes a second region A12, A14, A16, A18 in which is formed and an N pole is formed on the inner peripheral side. The first region A11, A13, A15, A17 and the second region A12, A14, A16, A18 are alternately arranged along the rotation direction R.

In the first region A11, A13, A15, A17, the direction of magnetization in the direction outward from the rotation axis O is S → N, and in the second regions A12, A14, A16, A18, the rotation axis O is outward. The direction of magnetization in the direction is N → S.

In each of the ring member 18 shown in FIGS. 2 and 3 and the ring member 18A shown in FIGS. 5 and 6, the directions of magnetization in the direction outward from the rotation axis OO of the bearing 1 alternate along the rotation direction. Different to.

In the present embodiment, in a bearing used for a machine tool spindle or the like, the machine tool spindle 10 is supported by a structure in which a spacer 20 is sandwiched between two bearings 1, and the bearing 1 or the spacer 20 is on the rotating side. As a non-contact type temperature sensor for measuring the temperature, a temperature sensor using a ring member 18 or 18A composed of a magnet and a magnetic sensor 17 is used.

Further, when the ring member 18A in which the magnetic poles shown in FIGS. 5 and 6 are magnetized to multiple poles is measured by the magnetic sensor 17, the magnetic flux density changes as shown in FIG. 7 are obtained a plurality of times per rotation, and the magnetic sensor is obtained. As for the output of 17, the frequency per rotation increases as the magnetic flux increases. When full-wave rectification and smoothing are performed, the higher the frequency, the smaller the ripple amplitude. Therefore, if the number of magnetic poles is large, the smoothing error is reduced and the measurement accuracy is improved. Further, even if the magnetizing strength of each magnetic pole varies, it is averaged by smoothing, so that detection becomes easy.

FIG. 8 is a block diagram showing a configuration of a circuit that receives a signal from the magnetic sensor 17. As shown in FIG. 8, the bearing device 50 further includes a signal processing unit 100 that receives the output of the magnetic sensor 17 and detects the state of the bearing 1. The signal processing unit 100 calculates the rotation speed Ni and the temperature Ti of the rotating wheel based on the output of the magnetic sensor 17.

The signal processing unit 100 includes an amplifier circuit 101 that amplifies the output of the magnetic sensor 17, a rectifier circuit 102 that full-wave rectifies and smoothes the waveform output by the amplifier circuit 101, and outputs a DC voltage, and a voltage output by the rectifier circuit 102. The inner ring temperature Ti is calculated from the A / D converter 103 that converts the voltage into a digital value, the counting circuit 104 that counts the number of waves of the signal waveform output by the amplifier circuit 101, and the digital value output by the A / D converter 103. It includes a calculation unit 105 that calculates the rotation speed Ni from the count value per unit time of the counter circuit 104.

The abnormality determination unit 110 determines the abnormality of the bearing 1 based on the inner ring temperature Ti and the rotation speed Ni output from the calculation unit 105.

FIG. 9 is a flowchart for explaining a first example of the abnormality determination process executed by the abnormality determination unit. The abnormality determination unit 110 monitors the output of the magnetic sensor 17 in step S1. Subsequently, in step S2, the abnormality determination unit 110 compares the inner ring temperature Ti detected from the output of the magnetic sensor 17 with the threshold value provided for each rotation speed Ni, and determines whether or not the threshold value has been exceeded. ..

If the detection temperature is lower than the threshold value in step S2, the sensor monitoring process of step S1 is repeatedly executed. On the other hand, when the detection temperature is higher than the threshold value in step S2, the abnormality determination unit 110 outputs an instruction signal for avoiding the abnormality operation so that the abnormality avoidance operation in step S3 is executed.

An example of abnormality avoidance operation control executed by the machine tool by this instruction signal is as follows. For example, control to lower the rotation speed than the current one, control to make the cutting depth of the blade smaller than the current one, control to supply or increase the supply amount of lubricating oil, stop machining (stop cutting and reduce or rotate the spindle rotation speed). To stop) and so on.

FIG. 10 is a flowchart for explaining a second example of the abnormality determination process executed by the abnormality determination unit. The abnormality determination unit 110 monitors the output of the magnetic sensor 17 in step S11. Subsequently, in step S12, the abnormality determination unit 110 calculates the rate of change of the inner ring temperature Ti detected from the output of the magnetic sensor 17 per unit time, and determines whether or not the calculated rate of change exceeds the determination value. (Determination of rate of change).

If the rate of change is smaller than the determination value in step S12, the sensor monitoring process of step S11 is repeatedly executed. On the other hand, when the detection value is larger than the determination value in step S12, the abnormality determination unit 110 outputs an instruction signal for avoiding the abnormality operation so that the abnormality avoidance operation in step S13 is executed.

Since the example of the abnormality avoidance operation control executed by the machine tool by this instruction signal is the same as the case of FIG. 9, the description will not be repeated.

In the bearing device of the present embodiment, since the rotation speed and the inner ring temperature can be calculated from the output of one magnetic sensor, it is possible to detect an abnormality (precursor such as seizure) generated in the bearing at an early stage. Therefore, it is possible to prevent the bearing from being damaged by reducing the operating speed of the machine tool.

FIG. 11 is a diagram showing a first modification of the bearing device. As in the bearing device 50A shown in FIG. 11, the ring member 18B, which is a magnet, may be arranged so as to be sandwiched between the inner ring spacers 6A and 6B.

FIG. 12 is a diagram showing a second modification of the bearing device. Like the bearing device 50B shown in FIG. 12, the ring member 18C, which is a magnet, is arranged at the end of the inner ring spacer 6C that is in contact with one of the inner rings, and the magnetic sensor 17 is placed in the outer ring spacer 7 so as to face the ring member 18C. It may be placed in.

As described above, according to the bearing device shown in the first embodiment, by arranging one ring member, it is possible to simultaneously detect the temperature and the rotation speed with a simple configuration. Therefore, since the number of sensors is small, the space for arranging the sensors can be small, which is advantageous in terms of cost.

[Embodiment 2]
In the first embodiment, a magnet is arranged on the rotating wheel or the rotating spacer, and a magnetic sensor is arranged on the fixed wheel or the fixed spacer so that the temperature and the rotation speed can be detected. In the second embodiment, in addition to the configuration of the first embodiment, a temperature sensor for detecting the temperature of the fixed wheel is further arranged.

FIG. 13 is a diagram showing the configuration of the bearing device according to the second embodiment. With reference to FIG. 13, the bearing device 50C includes a bearing 1 and a spacer 20 and has a structure in which the spacer 20 is sandwiched between the two bearings 1 and rotatably supports the machine tool spindle 10 (not shown). The bearing 1 includes an inner ring 2, an outer ring 3, a rolling element 4, and a cage 5. The spacer 20 includes an outer ring spacer 7 and an inner ring spacer 6.

In addition to the bearing 1 and the spacer 20, the bearing device 50C further includes a magnetic sensor 17, a ring member 18, a temperature sensor 40, and an abnormality diagnosis unit 120. Since the magnetic sensor 17 and the ring member 18 are the same as those in the first embodiment, the description thereof will not be repeated.

The temperature sensor 40 measures the temperature of the outer ring 3, which is a fixed ring. The abnormality diagnosis unit 120 diagnoses the abnormality of the bearing 1 based on the output of the temperature sensor 40 and the output of the magnetic sensor 17. The temperature sensor 40 may measure the outer ring spacer 7, which is a fixed spacer.

When the machine tool spindle 10 rotates at high speed, the bearing 1 generates heat due to contact between the inner ring rolling element raceway surface 14 and the rolling element 4, and the outer ring rolling element raceway surface 15 and the rolling element 4 due to the machining load. At this time, the temperature of the inner ring 2 into which the machine tool spindle 10 is inserted tends to be higher than that of the outer ring 3 inserted into the housing 13. The abnormality diagnosis unit 120 measures the temperature To of the outer ring 3 by the temperature sensor 40, and uses the difference between the temperature Ti of the inner ring 2 and the temperature To of the outer ring 3 to cause a change in the temperature difference different from the steady operation state. Judges as abnormal.

Further, the preload load estimation unit 105 can estimate the preload from the temperature To measured by the temperature sensor 40 and the temperature Ti calculated from the value measured by the magnetic sensor 17 for the ring member 18.

Specifically, for example, when the outer ring 3 is inserted into the housing and the shaft is supported by the inner ring 2, when the inner ring 2 rotates under the preload, the temperatures Ti and To rise and expand. Therefore, the preload of the bearing is higher than the initial set value. If this relationship is prepared by an arithmetic expression or the like, the preload can be estimated. The parameters used in the calculation formula are, for example, the rotational speed of the bearing, the outer ring temperature, the inner ring temperature, and the like.

As described above, in the bearing device 50C according to the second embodiment, the bearing is made from the measured temperature To of the fixed side member of the bearing or the spacer, the measured temperature Ti of the rotating side member, and the rotational speed Ni of the rotating member. The preload can be estimated. A ring member 18 magnetized so that N poles and S poles are alternately formed on the outer peripheral surface is fixed to the inner ring spacer provided between the inner rings of the bearing, and analog output is performed on the non-rotating side, for example, the outer ring spacer 7. If the magnetic sensor 17 is arranged, the temperature Ti of the inner ring spacer 6 can be measured in a non-contact manner, which can be used for estimating the preload of the bearing.

[Modification example]
In the first and second embodiments, if the transmission unit for wirelessly transmitting the output information generated by the magnetic sensor 17 to the outside is provided, the wiring does not need to be routed and the bearing device can be easily mounted. It should be noted that preferably, a power feeding device for supplying electric power to the power supply device may be further provided. As the power feeding device, in addition to the battery, a power generation device that generates electricity due to a temperature difference or vibration can be used.

FIG. 14 is a block diagram showing a configuration in which transmission / reception is performed wirelessly. The bearing device shown in the first or second embodiment further includes a data transmission unit 130 that wirelessly communicates the information measured by the magnetic sensor 17, preferably as shown in FIG.

If the output information generated by the magnetic sensor 17 is transmitted to the outside by the wireless transmission device 150, the same diagnosis can be performed by an external abnormality diagnosis device located at a position away from the machine tool or the like.

The wireless transmission device 150 (FIG. 14) includes a signal processing unit 100 and a data transmission unit 130. Since the signal processing unit 100 is the same as that shown in FIG. 8, the description will not be repeated. The data transmission unit 130 wirelessly transmits data to the receiving device 300.

The receiving device 300 is installed at a place away from the machine tool. The receiving device 300 includes a data receiving unit 301 that wirelessly receives data, a signal processing unit 302 that demodulates data from the received signal, and an abnormality determining unit 303 that receives data from the signal processing unit 302 and determines a bearing abnormality. including. Since the determination process of the abnormality determination unit 303 is the same as the process described with reference to FIGS. 9 and 10, the description will not be repeated.

The bearing device of the modified example includes a wireless transmission device 200 that wirelessly transmits the output information of the magnetic sensor 17 to the reception device 300 located at a position away from the machine tool. This makes it possible to diagnose whether or not an abnormality has occurred in the bearing of the machine tool even at a position away from the machine tool. This makes it even more convenient to monitor.

In the first and second embodiments, an example in which the bearing devices 50, 50A to 50C are inserted into the machine tool spindle 10 is shown as an example, but the bearing of this structure is used in the industrial field and the automobile field in addition to the machine tool spindle. It is possible to apply the device.

The embodiments disclosed this time should be considered to be exemplary and not restrictive in all respects. The scope of the present invention is shown by the scope of claims rather than the description of the embodiments described above, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 bearing, 2 inner ring, 3 outer ring, 4 rolling element, 5 cage, 6, 6A, 6B, 6C inner ring spacer, 7 outer ring spacer, 8 inner diameter part, 9 inner ring spacer inner diameter part, 10 machine spindle, 11 Outer diameter part, 12 outer ring bearing outer diameter part, 13 housing, 14,15 raceway surface, 16 inner ring spacer outer diameter part, 17 magnetic sensor, 18,18A, 18B, 18C ring member, 20 spacer, 40 temperature sensor, 50, 50A, 50B, 50C bearing device, 100, 302 signal processing unit, 101 amplifier circuit, 102 rectifier circuit, 103 A / D converter, 104 counting circuit, 105 calculation unit, 110, 303 abnormality judgment unit, 120 abnormality diagnosis unit , 130 data transmitter, 150, 200 wireless transmitter, 300 receiver, 301 data receiver, A1, A11, A13, A15, A17 first area, A2, A12, A14, A16, A18 second area.

Claims (5)

A bearing device that supports a rotating body with a single bearing or a structure in which a spacer is sandwiched between bearings.
The bearing includes an inner ring, an outer ring, and a rolling element.
The spacer includes an outer ring spacer and an inner ring spacer.
A magnetic sensor provided on the fixed side fixed ring of the inner ring and the outer ring, or the fixed side fixed spacer of the outer ring spacer and the inner ring spacer, and detecting magnetic characteristics.
It is arranged on the rotating wheel on the rotating side of the inner ring and the outer ring, or on the rotating spacer on the rotating side that rotates together with the rotating wheel of the outer ring spacer and the inner ring spacer, and the magnetic characteristics change depending on the temperature. Magnetic material member and
It is provided with a signal processing unit that receives the output of the magnetic sensor and detects the state of the bearing.
The magnetic member is magnetized so that the magnetic characteristics detected by the magnetic sensor fluctuate while the rotating wheel rotates.
The magnetic member is a ring member whose outer peripheral surface is arranged so as to face the magnetic sensor and is arranged on the rotating wheel or the rotating spacer.
In the ring member, the direction of magnetization in the direction from the rotation axis of the bearing to the outside is alternately different along the rotation direction.
The signal processing unit is a bearing device that calculates the rotation speed of the rotating wheel based on the frequency of the output signal of the magnetic sensor and calculates the temperature based on the amplitude of the output signal of the magnetic sensor . The ring member is
The first region where the N pole is formed on the inner peripheral side and the S pole is formed on the outer peripheral side,
It includes a second region where an N pole is formed on the outer peripheral side and an S pole is formed on the inner peripheral side.
The bearing device according to claim 1 , wherein the first region and the second region are alternately arranged along the rotation direction. A temperature sensor that measures the temperature of the fixed wheel or the fixed spacer,
The bearing device according to claim 1 or 2 , further comprising an abnormality diagnosis unit for diagnosing an abnormality of the bearing based on the output of the temperature sensor and the output of the magnetic sensor. A temperature sensor that measures the temperature of the fixed wheel or the fixed spacer,
The bearing device according to claim 1 or 2 , further comprising a preload load estimation unit that estimates a preload load of a bearing based on the output of the temperature sensor and the output of the magnetic sensor. The bearing device according to any one of claims 1 to 4 , further comprising a communication unit that wirelessly communicates information measured by the magnetic sensor.

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