JP2019152287A - Bearing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a bearing device capable of simultaneously detecting temperature and rotation speed with a simple configuration. A bearing device 50 further includes a magnetic sensor 17 and a ring member 18 in addition to a bearing 1 and a spacer 20. The magnetic sensor 17 is provided on the outer ring spacer 7 and detects magnetic characteristics. The ring member 18 is a magnet whose magnetic characteristics change depending on the temperature, and is arranged on the inner ring spacer 6. The ring member 18 is magnetized so that the magnetic characteristics 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. [Selection diagram] Fig. 1

Description

  The present invention relates to a bearing device, and 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 JP 2009-68533 A (Patent Document 1), in order to quickly and accurately 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 spacer are determined. And measure. The temperature on the rotating side is measured by a non-contact temperature sensor. In addition to pyroelectric infrared sensors and thermopiles that use infrared light, non-contact temperature sensors that use a ring-shaped temperature sensor (such as temperature-sensitive ferrite) to detect changes in magnetic properties have been proposed. Yes.

  Furthermore, a preload estimating means for estimating the preload of the bearing from the temperature on the fixed side and the rotation side of the bearing or spacer and the rotational speed of the rotating wheel is proposed.

JP 2009-68533 A

  Japanese Patent Application Laid-Open No. 2009-68533 discloses a method of using a change in magnetic characteristics of a ring member as a method of measuring the rotation side temperature of a bearing or a spacer. The detection procedure is not disclosed and there is room for improvement.

  We have also proposed a method for estimating the preload from the fixed side temperature and rotational side temperature of the bearing or spacer and the rotational speed of the rotating wheel. The rotational speed is measured from the main shaft with a rotation sensor or the like. Space is required to provide

  An object of the present invention is to provide a bearing device that is capable of detecting a temperature using magnetic characteristics and capable of detecting a rotation speed without providing a separate rotation sensor.

  The present disclosure relates to a bearing device that supports a rotating body in a structure in which a spacer is sandwiched between a single bearing or a bearing. 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. The bearing device is provided in a fixed ring on the fixed side of the inner ring and the outer ring, or a fixed spacer on the fixed side of the outer ring spacer and the inner ring spacer, and detects a magnetic characteristic, and the inner ring and the outer ring. And a magnetic member whose magnetic characteristics change depending on the temperature. The magnetic member is arranged on a rotating spacer on the rotating side that rotates together with the rotating wheel of the outer ring spacer and the inner ring spacer. 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 and detects 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 member is a ring member that is disposed on a rotating wheel or a rotating spacer so that an outer peripheral surface thereof faces the magnetic sensor. In the ring member, the magnetization directions in the direction from the rotation axis of the bearing toward the outside are alternately different along the rotation direction.

  Preferably, the ring member includes 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 the N pole is formed on the outer peripheral side and the S pole is formed on the inner peripheral side. The first region and the second region are alternately arranged along the rotation direction.

  Preferably, the bearing device further includes a temperature sensor that measures the temperature of the fixed ring or the fixed spacer, and an abnormality diagnosis unit that diagnoses an abnormality of the bearing based on the output of the temperature sensor and the output of the magnetic sensor.

  Preferably, the bearing device further includes a temperature sensor that measures the temperature of the fixed ring or the fixed spacer, and a preload load estimating unit that estimates the preload load of the bearing based on the output of the temperature sensor and the output of the magnetic sensor. .

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

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

It is a figure which shows the state which integrated the bearing apparatus of Embodiment 1 in the machine tool main shaft. It is sectional drawing which shows the cross section orthogonal to the rotating shaft of a ring member. It is sectional drawing of the ring member in the III-III cross section of FIG. It is a figure which shows the relationship between the rotation angle of a 1 pole pair ring member, and magnetic flux density. It is sectional drawing which shows the cross section orthogonal to the rotating shaft 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 a ring member of 4 pole pairs, and magnetic flux density. 2 is a block diagram showing a configuration of a circuit that receives a signal from a magnetic sensor 17. FIG. It is a flowchart for demonstrating the 1st example of the abnormality determination process which an abnormality determination part performs. It is a flowchart for demonstrating the 2nd example of the abnormality determination process which an abnormality determination part performs. It is a figure which shows the 1st modification of a bearing apparatus. It is a figure which shows the 2nd modification of a bearing apparatus. It is a figure which shows the structure of the bearing apparatus of Embodiment 2. FIG. It is a block diagram which shows the structure which transmits / receives wirelessly.

  Embodiments of the present invention will be described below with reference to the drawings. In the following drawings, the same or corresponding parts are denoted by the same reference numerals, and description thereof will not be repeated.

[Embodiment 1]
FIG. 1 is a view showing a state in which the bearing device of the first embodiment is incorporated in a machine tool spindle. The bearing device 50 supports the rotating body (the main shaft 10) by a single bearing or a structure in which a spacer is sandwiched between the 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 two bearings 1, and rotatably supports the machine tool spindle 10. The bearing 1 includes an inner ring 2, an outer ring 3, rolling elements 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 disposed around the main axis. The magnetic sensor 17 is provided in a fixed spacer on the fixed side of the outer ring spacer 7 and the inner ring spacer 6 and detects magnetic characteristics. The ring member 18 is a magnet in which a magnetic material whose magnetic characteristics change according to temperature is magnetized, and is disposed in the rotation spacer on the rotation 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 change during one rotation of the rotating wheel. The ring member 18 is disposed so that the outer peripheral surface faces the magnetic sensor 17.

  In FIG. 1, a 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. The machine tool main shaft 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 of the outer ring 3 and the outer ring spacer outer diameter portion 12 are inserted into the housing 13, and the rotation of the machine tool main shaft 10. Support.

  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 disposed on the rotating wheel on the rotating side of the inner ring 2 and the outer ring 3. You may make it do. A magnetic sensor may be disposed on the fixed ring with respect to the bearing alone, and a magnet having a magnetic material magnetized may be disposed on the rotating ring. Further, since the magnet is magnetized so that the magnetic characteristic (for example, the magnetic flux density) detected by the magnetic sensor 17 changes during one rotation of the rotating wheel, the magnet does not necessarily have to be in a ring shape. For example, a magnet may be attached to a part of the spacer.

  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 taken along the line III-III in FIG. 2 and 3, the ring member 18 includes 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 the second region A2 where the N 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 magnetization direction in the direction outward from the rotation axis O is S → N, and in the second region A2, the magnetization direction in the direction outward from the rotation axis O is N → S.

  FIG. 4 is a diagram showing the relationship between the rotation angle of the one-pole pair ring member shown in FIGS. 2 and 3 and the magnetic flux density. Since the magnetic flux density of the magnet constituting the ring member 18 changes due to a change in temperature, the magnetic sensor 17 can measure the change in magnetic flux density and calculate the temperature. For example, when a ferrite 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 increases.

  For example, in a radiation thermometer using infrared rays, if the infrared emissivity of the measurement object is small, the measurement accuracy is affected.In this embodiment, however, the temperature is detected by detecting magnetism. It is 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 of the inner ring spacer 6, and the magnetic sensor 17 is disposed so as to face the outer ring spacer 7, thereby changing the magnetic characteristics of the ring member 18. Is measuring. If an analog output type is used as the magnetic sensor 17, a sinusoidal output corresponding to the change in magnetic flux density can be obtained as shown in FIG.

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

  By smoothing the waveform after full-wave rectification and obtaining an average value of peak values, a characteristic value representing a change in amplitude can be calculated. 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 rotational 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 to 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, since it rotates at high speed, detection is easy if the signal of the magnetic sensor 17 is smoothed.

  That is, the ring members 18 and 18A are magnetized so that the S poles and the 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, so The change in polarity of the pole appears as an amplitude. The rotational speed can be calculated by counting the number of waves per hour. Then, compared with the amplitude of the waveform LT at a low temperature, the amplitude of the waveform HT at a high temperature when the temperature is higher than that is small. 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 rotational speed are calculated by one sensor. can do.

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

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

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

  The ring member 18 shown in FIG. 2 and FIG. 3 and the ring member 18A shown in FIG. 5 and FIG. 6 have alternating magnetization directions in the direction from the rotation axis OO of the bearing 1 along the rotation direction. Different.

  In the present embodiment, in a bearing used for a machine tool main shaft or the like, the machine tool main shaft 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 on the rotation side is supported. As a non-contact temperature sensor for measuring 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 magnetic sensor 17 is used to measure the ring member 18A in which the magnetic poles shown in FIG. 5 and FIG. 6 are magnetized in multiple poles, the magnetic flux density change as shown in FIG. As for the output of 17, the frequency per rotation increases as the magnetic pole increases. When the full-wave rectification and smoothing are performed, the higher the frequency, the smaller the ripple amplitude. Therefore, the larger the number of magnetic poles, the smaller the smoothing error and the better the measurement accuracy. Further, even if there is a variation in the magnetization intensity of each magnetic pole, since it is averaged by smoothing, 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 rotational 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 outputs a DC voltage by full-wave rectifying and smoothing the waveform output from the amplifier circuit 101, and a voltage output from the rectifier circuit 102. An A / D converter 103 that converts the signal to a digital value, a counting circuit 104 that counts the wave number of the signal waveform output from the amplifier circuit 101, an inner ring temperature Ti from the digital value output from the A / D converter 103, and And a calculation unit 105 that calculates the rotational speed Ni from the count value per unit time of the counting circuit 104.

  Based on the inner ring temperature Ti and the rotational speed Ni output from the calculation unit 105, the abnormality determination unit 110 determines the abnormality of the bearing 1.

  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 S <b> 2, the abnormality determination unit 110 compares the inner ring temperature Ti detected from the output of the magnetic sensor 17 with a threshold provided for each rotation speed Ni, and performs a threshold determination as to whether or not the threshold has been exceeded. .

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

  An example of the abnormality avoidance operation control executed by the machine tool in response to this instruction signal is as follows. For example, control to lower the rotation speed than the current control, control to reduce the cutting depth of the blade smaller than the present, control to supply the lubricant or increase the supply amount, stop processing (cutting is stopped and the spindle rotation speed is reduced or rotated) Stop).

  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 a change rate per unit time of the inner ring temperature Ti detected from the output of the magnetic sensor 17, and determines whether or not the calculated change rate exceeds a determination value. (Change rate determination).

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

  An example of the abnormality avoidance operation control executed by the machine tool in response to this instruction signal is the same as in the case of FIG.

  In the bearing device of the present embodiment, the rotational speed and the inner ring temperature can be calculated from the output of one magnetic sensor, so that an abnormality (a sign such as seizure) occurring in the bearing can be detected at an early stage. For this reason, it is possible to prevent the bearing from being damaged by reducing the operating speed of the machine tool.

  FIG. 11 is a diagram illustrating a first modification of the bearing device. As in the bearing device 50A shown in FIG. 11, the ring member 18B that is a magnet may be sandwiched between the inner ring spacers 6A and 6B.

  FIG. 12 is a diagram illustrating a second modification of the bearing device. As in the bearing device 50B shown in FIG. 12, a ring member 18C, which is a magnet, is disposed between the inner ring spacers 6C and in contact with one of the inner rings, and the magnetic sensor 17 is disposed so as to face the ring member 18C. You may arrange in.

  As described above, according to the bearing device shown in the first embodiment, it is possible to simultaneously detect the temperature and the rotational speed with a simple configuration by arranging one ring member. Therefore, since the number of sensors is small, the sensor arrangement space is 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 fixing 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 ring is further arranged.

  FIG. 13 is a diagram illustrating a configuration of the bearing device according to the second embodiment. Referring to FIG. 13, the bearing device 50 </ b> C includes a bearing 1 and a spacer 20 and sandwiches the spacer 20 between two bearings 1, and rotatably supports a machine tool spindle 10 (not shown). The bearing 1 includes an inner ring 2, an outer ring 3, rolling elements 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 50 </ b> C further includes a magnetic sensor 17, a ring member 18, a temperature sensor 40, and an abnormality diagnosis unit 120. Since magnetic sensor 17 and ring member 18 are the same as in the first embodiment, description thereof will not be repeated.

  The temperature sensor 40 measures the temperature of the outer ring 3 that is a fixed ring. The abnormality diagnosis unit 120 diagnoses an 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 main shaft 10 rotates at a 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 with 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 show a change in temperature difference different from the steady operation state. Is determined to be abnormal.

  Further, the preload load estimating 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 of the ring member 18.

  Specifically, in the case where the outer ring 3 is inserted into the housing and the shaft is supported by the inner ring 2, for example, when the inner ring 2 is rotated under a preload, the temperatures Ti and To rise and expand. Therefore, the preload of the bearing rises from 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, from the measured temperature To of the fixed member of the bearing or spacer, the measured temperature Ti of the rotating 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 an inner ring spacer provided between the inner rings of the bearings, and an analog output is provided to 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 and can be used for estimating the bearing preload.

[Modification]
In the first and second embodiments, if a transmission unit that wirelessly transmits the output information generated by the magnetic sensor 17 is provided, wiring is not necessary, and the bearing device can be easily mounted. In addition, Preferably, you may further provide the electric power feeder which supplies electric power to this. As the power supply device, in addition to the battery, a power generation device that generates power by a temperature difference or vibration can be used.

  FIG. 14 is a block diagram showing a configuration for wireless transmission / reception. The bearing device shown in the first or second embodiment preferably further includes a data transmission unit 130 for wirelessly communicating information measured by the magnetic sensor 17 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. Signal processing unit 100 is the same as that shown in FIG. 8, and description thereof will not be repeated. The data transmission unit 130 transmits data to the reception device 300 wirelessly.

  The receiving device 300 is installed at a location 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 determination unit 303 that receives data from the signal processing unit 302 and determines a bearing abnormality. including. Note that the determination process of abnormality determination unit 303 is the same as the process described with reference to FIGS. 9 and 10, and therefore description thereof will not be repeated.

  The bearing device according to the modification includes a wireless transmission device 200 that wirelessly transmits output information of the magnetic sensor 17 to the reception device 300 located away from the machine tool. Thereby, it is 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 more convenient for monitoring.

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

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  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 tool spindle, 11 Outer diameter part, 12 Outer ring spacer outer diameter part, 13 Housing, 14, 15 Raceway surface, 16 Inner ring spacer outer peripheral surface, 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 Count circuit, 105 Arithmetic unit, 110, 303 Abnormality determination unit, 120 Abnormality diagnosis unit , 130 Data transmitter, 150, 200 Wireless transmitter, 300 receiver, 301 Data receiver, A1, A11, A13, A15, A17 1st Pass, A2, A12, A14, A16, A18 second region.

Claims (7)

A bearing device that supports a rotating body with a structure in which a spacer is sandwiched between bearings alone or 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 for detecting a magnetic characteristic provided in a fixed ring on the fixed side of the inner ring and the outer ring, or a fixed spacer on the fixed side of the outer ring spacer and the inner ring spacer;
The magnetic characteristics change depending on the temperature. A magnetic member that
The magnetic material member is magnetized so that the magnetic characteristics detected by the magnetic sensor fluctuate while the rotating wheel rotates. A signal processing unit that receives the output of the magnetic sensor and detects the state of the bearing;
The bearing device according to claim 1, wherein the signal processing unit calculates a rotation speed and a temperature of the rotating wheel based on an output of the magnetic sensor. The magnetic member is a ring member that is disposed so that an outer peripheral surface faces the magnetic sensor and is disposed in the rotating wheel or the rotating spacer.
The bearing device according to claim 1, wherein the ring member has alternately different magnetization directions along a rotation direction in a direction from the rotation axis of the bearing toward the outside. The ring member is
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;
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 bearing device according to claim 3, wherein the first region and the second region are alternately arranged along the rotation direction. A temperature sensor for measuring the temperature of the fixed ring or the fixed spacer;
The bearing device according to claim 1, further comprising an abnormality diagnosis unit that diagnoses an abnormality of the bearing based on an output of the temperature sensor and an output of the magnetic sensor. A temperature sensor for measuring the temperature of the fixed ring or the fixed spacer;
The bearing device according to any one of claims 1 to 4, further comprising a preload load estimating unit configured to estimate a preload load of the bearing based on an output of the temperature sensor and an output of the magnetic sensor.   The bearing device according to claim 1, further comprising a communication unit that wirelessly communicates information measured by the magnetic sensor.

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