Bearing abnormality diagnosis system

Abstract

To provide a bearing abnormality diagnosis system capable of easily determining an abnormality of a bearing during use, and facilitating attachment / detachment to / from a device to which the bearing is applied.SOLUTION: A bearing abnormality diagnosis system (1) comprises: a bearing (3); a member to be detected (5) for rotation detection that is attached to a rotary side member (15) of the bearing (3); a sensor unit (11) spaced apart from the bearing (3) and the member to be detected (5) and provided facing the member to be detected (5), where the sensor unit (11) has a rotation detection unit (7) and a temperature detection unit (9) that detect the rotation and temperature of the member to be detected (5); and an abnormality diagnosis device (13) that determines whether or not there is an abnormality in the bearing (3) based on the output of the sensor unit (11), where the abnormality diagnosis device (13) has a setting unit (43) in which a reference temperature value is stored, and a determination unit (45) that determines whether or not there is an abnormality in the bearing (3) by comparing a temperature detection value detected by the temperature detection unit (9) with the reference temperature value.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a system for diagnosing abnormalities in bearings. [Background technology]

[0002] Several techniques have been proposed as methods for diagnosing abnormalities in bearings. For example, Patent Document 1 discloses a wheel bearing device in which a step is formed on the outer periphery of the inner end of the outer member (outer ring) with a diameter slightly smaller than the outer diameter, and an adhesive is applied to the backside of this step, and a temperature indicator in sheet form is affixed. By providing the temperature indicator in this way, the state of deterioration can be easily detected visually during vehicle inspection without disassembling the bearing.

[0003] As another example, Patent Document 2 discloses a sensor-equipped wheel support bearing in which double rows of rolling elements are interposed between an outer member and an inner member. The sensor unit consists of a ring member or sensor mounting member attached to the inner circumferential surface of the outer member, which is the fixed member, a strain sensor that measures the strain of that member, and various sensors (temperature sensor, acceleration sensor, etc.) that detect the condition of the wheel support bearing. Because the various sensors that detect the condition of the wheel support bearing are attached to the ring member, it is easy to mass-produce and reduces costs. Furthermore, by providing the strain sensor and various sensors on the ring member or sensor mounting member, it becomes possible to measure the load and the condition of the wheel support bearing in a single location. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-216230 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-078129 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the wheel support bearing device disclosed in Patent Document 1, the temperature indicator is visually inspected during vehicle inspection to determine whether or not there is an abnormality based on a change in color, so it is not possible to determine whether or not there is an abnormality while the bearing is in use (while the vehicle is running). On the other hand, in the sensor-equipped wheel support bearing disclosed in Patent Document 2, a sensor unit (ring member) equipped with various sensors is fixed to the inner diameter surface of the outer member, so the wiring for the various sensors must be drawn from the inside to the outside of the outer member. This makes the wiring complicated when attaching and detaching the wheel support bearing to and from the vehicle.

[0006] Therefore, in order to solve the above problems, an object of the present invention is to provide a bearing abnormality diagnosis system that can easily determine whether a bearing is abnormal even while the bearing is in use, and that can easily be attached to and detached from the device to which the bearing is applied. [Means for solving the problem]

[0007] In order to achieve the above object, the bearing abnormality diagnosis system according to the present invention provides: a bearing having a rotating member, a fixed member, and rolling elements interposed between the rotating member and the fixed member; a detection member for detecting rotation attached to the rotation-side member of the bearing; a sensor unit provided at a distance from the bearing and the detection member and facing the detection member, a rotation detection unit that detects rotation of the detection target member; a temperature detection unit that detects the temperature of the detection target unit; a sensor unit having An abnormality diagnosis device that determines whether or not there is an abnormality in the bearing based on an output of the sensor unit, a setting unit in which a preset reference temperature value is stored; a determination unit that determines whether or not there is an abnormality in the bearing by comparing the temperature detected by the temperature detection unit with the reference temperature value; an abnormality diagnosis device having Equipped with.

[0008] According to this configuration, by providing a temperature detection section within the casing of the sensor unit used for rotation detection and measuring the temperature of a detection member provided on the rotating member of the bearing, it is possible to diagnose bearing abnormalities whether the bearing is in use or not. Moreover, this bearing abnormality diagnosis is possible without adding or modifying the temperature detection structure. Furthermore, since the temperature detection section is built into the sensor unit provided at a distance from the bearing and the detection member and measures the temperature of the detection member without contact, there is no need to pull out temperature detection wiring from inside the bearing, making it easy to attach and detach the bearing to and from the device to which it is applied.

[0009] In one embodiment of the present invention, the abnormality diagnosis device may have an integrating unit that, when the detected temperature value is higher than a predetermined first reference temperature value and lower than a predetermined second reference temperature value, integrates the amount of time that the detected temperature value has exceeded the first reference temperature value, and the determination unit may be configured to issue a warning message when the integrated value of the amount of time that has exceeded the limit integrated by the integrating unit exceeds a predetermined reference integrated value. This configuration makes it possible to take appropriate measures to prevent bearing abnormalities from occurring, thereby reducing losses due to suspension of use of equipment to which the bearing is applied.

[0010] In one embodiment of the present invention, the determination unit may be configured to determine that an abnormality exists in the bearing and issue warning information when the detected temperature value is equal to or greater than the second reference temperature value. With this configuration, if an abnormality occurs in the bearing, the user can take appropriate action, such as immediately ceasing use of the device.

[0011] In one embodiment of the present invention, the abnormality diagnosis device may include a correction unit that calculates a bearing temperature estimate by multiplying the detected temperature value by a correction coefficient for estimating the temperature of the bearing. Because the detection target is located away from the outer ring rolling surface and the inner ring rolling surface, which are heat sources of the bearing, it is expected that the temperature of the detection target will be lower than the temperature of the bearing. Therefore, by providing a correction unit configured as described above, it becomes possible to detect the bearing temperature more accurately.

[0012] The above-described bearing abnormality diagnosis system can be applied to bearings for various applications. For example, in one embodiment of the present invention, the bearing may be a wheel bearing. In another embodiment, the bearing may be a rolling bearing mounted on an electric vertical take-off and landing aircraft that flies by rotating a plurality of drive units each having a rotor and a motor that rotates the rotor, and that rotatably supports a rotation shaft of the drive unit.

[0013] The electric vertical take-off and landing aircraft of the present invention includes a plurality of drive units each having a rotor and a motor for rotating the rotor, and the above-described bearing abnormality diagnosis system including bearings for rotatably supporting the rotation shafts of the drive units. With this configuration, the above-described advantages can be obtained even in electric vertical take-off and landing aircraft (so-called flying cars), which are expected to be an alternative means of transportation to automobiles. [Effects of the Invention]

[0014] As described above, the bearing abnormality diagnosis system according to the present invention makes it possible to easily determine whether a bearing is abnormal even while the bearing is in use, and to easily perform the work of attaching and detaching the bearing to the device to which it is applied. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a cross-sectional view showing a schematic configuration of a bearing abnormality diagnosis system according to an embodiment of the present invention. [Figure 2] 2 is an enlarged cross-sectional view showing a part of a bearing abnormality diagnostic system according to a modified example of the embodiment shown in FIG. 1. FIG. [Figure 3] FIG. 10 is a perspective view showing an electric vertical take-off and landing aircraft to which a bearing diagnostic device according to another embodiment of the present invention is applied. [Figure 4] FIG. 4 is a longitudinal cross-sectional view showing part of a motor in a drive unit of the electric vertical take-off and landing aircraft of FIG. 3. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to this embodiment.

[0017] FIG. 1 shows a bearing abnormality diagnostic system 1 according to one embodiment of the present invention. In this embodiment, an abnormality diagnostic system for wheel bearings used to support the wheels of a vehicle such as a large truck will be described as an example. In the following description, the side that is closer to the outside of the vehicle when assembled to the vehicle (the left side in FIG. 1) will be referred to as the outboard side, and the side closer to the center (the right side in FIG. 1) will be referred to as the inboard side. For convenience of explanation, the outboard side and inboard side may also be simply referred to as the "left side" and "right side", etc.

[0018] The bearing abnormality diagnosis system 1 comprises a bearing 3 to be diagnosed for an abnormality, a detection member 5 for detecting the rotation of the bearing 3, a sensor unit 11 having a rotation detection section 7 and a temperature detection section 9, and an abnormality diagnosis device 13 that determines whether or not there is an abnormality in the bearing 3 based on the output of the sensor unit 11.

[0019] The bearing 3 has a rotating member, a fixed member, and rolling elements interposed between the rotating member and the fixed member. In the illustrated example, the bearing 3 is configured as a double-row tapered roller bearing. Specifically, the bearing 3 includes an outer member 15 having tapered double-row outer raceway surfaces 15a formed on its inner periphery, a pair of left and right inner members (inner rings) 17 having tapered inner raceway surfaces 17a formed on their outer peripheries facing the double-row outer raceway surfaces 15a, tapered rollers as rolling elements 19 interposed between the two raceway surfaces 15a, 17a, and a cage 21 that holds these rolling elements 19 so that they can roll freely. In this embodiment, the outer member 15 includes an outer ring 25 that faces the inner member (inner ring) and a flange member 27 located on the outer periphery of the outer ring 25. In this embodiment, the bearing 3 is configured as an outer ring rotating type, with the outer member 15 corresponding to the rotating member and the inner member 17 corresponding to the fixed member. The bearing 3 is configured as a back-to-back type double-row tapered roller bearing in which the small diameter end faces of a pair of inner members 17 are set together with each other. Seal members 23 are attached to the openings at both axial ends of the annular space formed between the outer member 15 and the inner member 17. The seal members 23 prevent the lubricating grease sealed inside the bearing 3 from leaking out and prevent foreign matter such as rainwater and dust from entering the inside of the bearing 3 from the outside.

[0020] The flange member 27 has a cylindrical portion 27a and a wheel mounting flange 27b that protrudes radially outward from the outboard end of the cylindrical portion 27a. The bearing 3 according to this embodiment is a wheel bearing 3 as described above, and rotatably supports a wheel (not shown) via the wheel mounting flange 27b, to which the wheel is attached at the outboard end. The outer member 15 is formed by press-fitting the outer ring 25 onto the inner peripheral surface of the cylindrical portion 27a of the flange member 27.

[0021] A locking portion 29 that protrudes slightly radially outward is provided on the outboard side of the outer ring 25 and abuts against a stepped portion 31 formed on the inner circumferential surface of the cylindrical portion 27a of the flange member 27. On the other hand, on the outboard side of the locking portion 29 of the outer ring 25, a snap ring 33 is fitted into a fitting groove on the inner circumferential surface of the cylindrical portion 27a of the flange member 27. The stepped portion 31, locking portion 29, and snap ring 33 determine the relative positions of the outer ring 25 and the flange member 27. A brake drum is attached to the radially outer portion of the inboard side of the wheel mounting flange 27b. The outer ring 25 and flange member 27 do not have to be separate bodies as shown in the figure, but may be formed as an integrated outer member 15.

[0022] A fixed shaft 37 of a knuckle (not shown) is inserted into the inner diameter portion of the inner member 17 and is fixed by tightening with a nut 39, whereby the wheel mounting flange 27b is rotatably supported relative to the fixed shaft 37.

[0023] The detected member 5 is attached to the rotating member of the bearing 3. In this example, the detected member 5 is fixed by press fitting to the inboard outer periphery of the flange member 27 of the outer member 15. In this embodiment, a pulser ring is used as the detected member 5. This pulser ring, which is the detected member 5, has a large number of teeth 5a arranged at equal intervals in the circumferential direction on its surface facing the inboard side.

[0024] Sensor unit 11 is provided so as to be spaced apart from bearing 3 and detection target member 5 and to face detection target member 5. Sensor unit 11 includes a casing 41 and a rotation detection section 7 (rotation sensor) that detects the rotation of detection target member 5 and a temperature detection section 9 (temperature sensor) that detects the temperature of the detection target member, both housed inside casing 41. Sensor unit 11 is fixed to a fixed member (for example, a knuckle (not shown) of fixed shaft 37).

[0025] If the rotation detection system is of the passive type, the rotation detector 7 is a pickup coil type sensor, and the target member facing it is a tooth-shaped pulser ring that outputs an ABS signal (Antilock Brake System). Note that the rotation detection system may be of the active type, and the rotation detector 7 may be a sensor equipped with a magnet and a Hall IC.

[0026] The temperature detection unit 9 of this embodiment is made up of a temperature sensor, which measures the temperature of the detection target member 5 (the pulser ring in this example) in a non-contact manner. The temperature sensor may be, for example, an infrared temperature sensor or a thermistor, but is not limited to these. When an infrared temperature sensor is used as the temperature detection unit 9, the surface of the detection target member 5, the pulser ring, may be blackened to increase its infrared emissivity. The temperature detection unit 9 monitors the temperature rise of the bearing 3, making it possible to diagnose abnormalities in the bearing 3.

[0027] The manner in which the detected member 5 is attached to the rotating member of the bearing 3 is not limited to the example shown in Fig. 1. For example, as shown as a modified example in Fig. 2, a magnetic pulser ring (magnetic encoder) magnetized with alternating north and south poles may be used as the detected member 5, and this detected member 5 may be provided integrally with the seal plate 23a, which is a component of the seal member 23, on the inboard side of the seal plate 23a. In this case, a magnetic sensor is used as the rotation detection section 7 of the sensor unit 11, and the magnetic sensor detects the magnetic flux of the north and south poles to output an ABS signal.

[0028] In addition, when the bearing 3 is a wheel bearing used in a vehicle such as a large truck, as in this embodiment, the casing 41 of the sensor unit 11 is required to have measures to prevent the intrusion of foreign matter such as water, oil, muddy water, and flying stones, and therefore it is preferable to improve the sealing properties of the casing 41 by forming at least the outside of it from a cushioning material (resin, rubber, etc.).

[0029] Next, an abnormality diagnosis by the abnormality diagnosis device 13 using the temperature detection unit 9 of the sensor unit 11 shown in Fig. 1 will be described. The abnormality diagnosis device 13 includes a setting unit 43 in which a preset reference temperature value is stored, and a determination unit 45 that determines whether or not there is an abnormality in the bearing 3 by comparing the temperature detection value detected by the temperature detection unit 9 with the reference temperature value. In this embodiment, the abnormality diagnosis device 13 further includes an integration unit 47 that performs time integration, which will be described later.

[0030] Specifically, the setting unit 43 stores two reference temperature values in advance: a first reference temperature value and a second reference temperature value that is higher than the first reference temperature value. The second reference temperature value is set to a temperature value at which it should be determined that an abnormality has occurred in the bearing 3. On the other hand, the first reference temperature value is set to a temperature value at which it should be determined that a precursory state that is likely to lead to an abnormality is present, although it is not necessary to immediately determine that an abnormality has occurred. For example, 130°C is set as the first reference temperature value, and 150°C is set as the second reference temperature value.

[0031] If the temperature detection value output from the temperature detection section 9 of the sensor unit 11 is higher than the first reference temperature value and lower than the second reference temperature value, the judgment section 45 judges that the bearing 3 is in a pre-abnormal state and causes the integrating section 47 to integrate the excess time during which the temperature detection value exceeded the first reference temperature value. Thereafter, if the integrated value of the excess time integrated by the integrating section 47 exceeds a preset reference integrated value, the judgment section 45 issues warning information. This warning information is, for example, warning information that prompts maintenance such as inspection or replacement of the bearing 3.

[0032] This configuration makes it possible to take appropriate measures to prevent abnormalities from occurring in the bearing 3, thereby reducing losses due to suspension of use of equipment to which the bearing 3 is applied. For example, when this bearing abnormality diagnosis system 1 is applied to wheel bearings 3 used in large trucks, buses, etc., early detection of signs of failure makes it possible to plan in advance the replacement timing of the wheel bearings 3 so as not to cause disruptions to operation, minimizing losses due to suspension of operation.

[0033] On the other hand, if the detected temperature value is equal to or higher than the second reference temperature value, the judgment unit 45 judges that there is an abnormality in the bearing 3 (for example, seizure of the bearing 3) and issues warning information. This warning information is, for example, warning information that instructs the user to stop using the device in which the bearing 3 is installed (in this example, running the vehicle). With this configuration, if an abnormality occurs in the bearing 3, the user can take appropriate action, such as immediately stopping use of the device.

[0034] Note that, since the detection target member 5 is located away from the outer ring 25 rolling surface and the inner ring rolling surface, which are heat sources of the bearing 3, it is expected that the temperature of the detection target member 5 will be lower than the temperature of the bearing 3. Therefore, in order to detect the temperature of the bearing 3 more accurately, the abnormality diagnosis device 13 may be provided with a correction unit that calculates a bearing temperature estimate value by multiplying the detected temperature value by a correction coefficient for estimating the temperature of the bearing 3.

[0035] According to the bearing abnormality diagnosis system 1 of this embodiment described above, by providing the temperature detection unit 9 inside the casing 41 of the sensor unit 11 used for rotation detection and measuring the temperature of the detection target member 5 attached to the rotating member of the bearing 3, it is possible to diagnose abnormalities in the bearing 3 whether or not the bearing 3 is in use. Moreover, this type of bearing abnormality diagnosis is possible without adding or modifying the temperature detection structure. Furthermore, the temperature detection unit 9 is built into the sensor unit 11, which is provided at a distance from the bearing 3 and the detection target member 5, and measures the temperature of the detection target member 5 in a non-contact manner, so there is no need to pull out temperature detection wiring from inside the bearing 3, and the bearing 3 can be easily attached and detached to and from the device to which it is applied.

[0036] In this embodiment, an example has been described in which the bearing 3 is an outer ring rotating type, but the bearing 3 may also be an inner ring rotating type. Furthermore, the bearing 3 of the bearing abnormality diagnosis system 1 is not limited to a wheel bearing, and can be applied to various types of bearings.

[0037] Next, a bearing abnormality diagnosis system 1 according to another embodiment will be described, which is an example in which the bearing abnormality diagnosis system 1 of the present invention is applied to bearings for other uses. Figure 3 shows an electric vertical take-off and landing aircraft 51 on which the bearing abnormality diagnosis system 1 according to this embodiment is mounted. The bearing abnormality diagnosis system 1 according to this embodiment differs from the embodiment described above with reference to Figures 1 and 2 in the use and type of bearing, but is otherwise similar to the embodiment described above. Therefore, in the following description, the differences from the embodiment described above will be mainly described, and a description of the other aspects will be omitted.

[0038] In recent years, flying cars, or so-called flying cars, have been attracting attention as an alternative means of transportation to cars. Flying cars are expected to solve the above-mentioned social problems and are expected to be used in a variety of situations, such as intra-regional transportation, inter-regional transportation, tourism and leisure, emergency medical care, and disaster relief.

[0039] Vertical take-off and landing aircraft (VTOL), as shown in the figure, are attracting attention as flying cars. VTOLs can ascend and descend vertically between the sky and takeoff and landing sites, eliminating the need for runways and offering excellent convenience. In particular, in recent years, due to societal demands for reducing CO2 emissions, electric vertical take-off and landing aircraft51 (eVTOL), which fly using batteries and motors, have become the mainstream of development.

[0040] The electric vertical take-off and landing aircraft 51 shown in Fig. 3 is a multicopter having a main body 53 located in the center of the aircraft and four drive units 55 arranged in the front, rear, left, and right directions. The drive units 55 are devices that generate lift and thrust for the electric vertical take-off and landing aircraft 51, and the electric vertical take-off and landing aircraft 51 flies when driven by the drive units 55. The electric vertical take-off and landing aircraft 51 may have multiple drive units 55, and is not limited to four.

[0041] The main body 53 has a living space large enough to accommodate a crew member (for example, one or two people). This living space is provided with an operating system for determining the direction of travel and altitude, and instruments that indicate altitude, speed, flight position, etc. Four arms 57 extend from the main body 53, and a drive unit 55 is provided at the tip of each arm 57. In the illustrated example, a circular ring 61 that covers the rotating periphery of the rotor 59 is integrally provided on each arm 57 to protect the rotor 59. In addition, a skid 63 that supports the aircraft during landing is provided below the main body 53.

[0042] The drive unit 55 has rotors 59 and a motor 65 that rotates the rotors 59. In the drive unit 55, a pair of rotors 59 are provided on both axial sides of the motor 65. Each rotor 59 has two blades that extend radially outward.

[0043] The main body 53 is provided with a battery (not shown) and a control device (not shown). The control device is also called a flight controller. The electric vertical take-off and landing aircraft 51 is controlled by the control device, for example, as follows: The control device outputs a command to change the rotation speed to the motor 65 that should adjust the lift based on the difference between the current attitude and the target attitude. Based on this command, the inverter provided in the motor 65 adjusts the amount of power sent from the battery to the motor 65, and the rotation speed of the motor 65 (and the rotor 59) is changed. Furthermore, the adjustment of the rotation speed of the motors 65 is performed simultaneously for multiple motors 65, and the attitude of the aircraft is determined thereby.

[0044] 4 shows a partial cross-sectional view of the motor 65 in the drive unit 55. The above-mentioned rotor 59 is attached to one end (upper side of the figure) of the rotary shaft 67 of the motor 65, and a rotor is attached to the other end (lower side of the figure). The rotor is disposed opposite a stator fixed to a housing 69 and is rotatable relative to the stator. The motor 65 can be configured as an outer rotor brushless motor 65 or an inner rotor brushless motor 65.

[0045] The motor 65 includes a housing (device housing) 69, a rotor (not shown), a stator (not shown), an inverter (not shown), and two bearings 3. In this example, an inner ring rotating type rolling bearing (more specifically, a deep groove ball bearing) is used as the bearing 3. That is, the bearing 3 includes an inner ring 71 which is a rotating member, an outer ring 73 which is a fixed member, and balls 75 which are rolling elements interposed between the inner and outer rings 71, 73. The balls 75 are held in place by a cage 77.

[0046] The housing 69 has an outer cylinder 69a and an inner cylinder 69b, with a coolant flow path 69c provided between them. By flowing a coolant through this coolant flow path 69c, excessive temperature rise can be prevented. The material of the housing 69 is not particularly limited, and for example, an iron-based material or CFRP (carbon fiber reinforced plastic) can be used.

[0047] The bearing 3 rotatably supports the rotating shaft 67 within the housing 69. In Fig. 2, the outer diameter shape of the outer ring 25 of the bearing 3 is the same as the shape of the fitting portion on the inner periphery of the housing 69, and the bearing 3 is fitted directly into the housing 69 without an intervening bearing housing or the like. An inner ring spacer 79 and an outer ring spacer 81 are inserted between the two bearings 3, and a preload is applied.

[0048] The configuration of the bearing 3 in the drive unit 55 is not limited to the example in Fig. 4. In Fig. 4, the example in which the rotation shaft 67 of the motor 65 and the rotation shaft of the rotor 59 are the same rotation shaft 67 is shown, but the rotation shaft 67 of the motor 65 and the rotation shaft of the rotor 59 may be connected via a transmission mechanism. In this case, the bearing 3 supporting the rotation shaft 67 in the drive unit 55 may be the bearing 3 supporting the rotation shaft 67 of the motor 65 or the bearing 3 supporting the rotation shaft of the rotor 59.

[0049] In this embodiment as well, by providing a temperature detection unit 9 inside the casing 41 of the sensor unit 11 used for rotation detection and measuring the temperature of the detection target 5 attached to the rotating member of the bearing 3 (inner ring 71 in this example), it is possible to diagnose abnormalities in the bearing 3 whether or not the bearing 3 is in use. Moreover, this type of abnormality diagnosis for the bearing 3 is possible without adding or modifying the temperature detection structure. Furthermore, the temperature detection unit 9 is built into the sensor unit 11, which is provided at a distance from the bearing 3 and the detection target 5, and measures the temperature of the detection target 5 in a non-contact manner, so there is no need to pull out temperature detection wiring from inside the bearing 3, and the bearing 3 can be easily attached and detached to and from the device to which it is applied.

[0050] In this embodiment, the bearing 3 is not limited to the deep groove ball bearing 3 shown as an example, and an angular contact ball bearing 3 may also be used.

[0051] Although the preferred embodiments of the present invention have been described above with reference to the drawings, various additions, modifications, and omissions can be made without departing from the spirit of the present invention. Therefore, such additions, modifications, and omissions are also included within the scope of the present invention. [Explanation of symbols]

[0052] 1. Bearing abnormality diagnosis system 3. Bearings 5. Detected member 7 Rotation detection unit 9 Temperature detection unit 11 Sensor unit 13 Abnormality diagnosis device 15 Outer member (rotating member) 17 Inner member (fixed side member) 43 Setting section 45 Judgment section 47 Integration Section

Claims

1. a bearing having a rotating member, a fixed member, and rolling elements interposed between the rotating member and the fixed member; a detection member for detecting rotation attached to the rotation-side member of the bearing; a sensor unit provided at a distance from the bearing and the detection member and facing the detection member, a rotation detection unit that detects rotation of the detection target member; a temperature detection unit that detects the temperature of the detection target member; a sensor unit having An abnormality diagnosis device that determines whether or not there is an abnormality in the bearing based on an output of the sensor unit, a setting unit in which a preset reference temperature value is stored; a determination unit that determines whether or not there is an abnormality in the bearing by comparing the temperature detected by the temperature detection unit with the reference temperature value; an abnormality diagnosis device having Equipped with the temperature detection unit is built into the sensor unit, which is provided at a distance from the bearing and the detection target member; Bearing abnormality diagnosis system.

2. 2. The bearing abnormality diagnosis system according to claim 1, the abnormality diagnosis device has an integrating unit that, when the temperature detection value is higher than a predetermined first reference temperature value and lower than a predetermined second reference temperature value, integrates an excess time during which the temperature detection value exceeds the first reference temperature value; the determination unit issues a warning message when the accumulated value of the overtime accumulated by the accumulation unit exceeds a predetermined reference accumulated value. Bearing abnormality diagnosis system.

3. 3. The bearing abnormality diagnosis system according to claim 1, When the detected temperature value is equal to or higher than a predetermined second reference temperature value, the determination unit determines that an abnormality exists in the bearing and issues warning information. Bearing abnormality diagnosis system.

4. 4. The bearing abnormality diagnosis system according to claim 1, the abnormality diagnosis device has a correction unit that calculates a bearing temperature estimation value by multiplying the temperature detection value by a correction coefficient for estimating the temperature of the bearing, Bearing abnormality diagnosis system.

5. 5. The bearing abnormality diagnosis system according to claim 1, wherein the bearing is a wheel bearing.

6. 5. A bearing abnormality diagnosis system according to claim 1, wherein the bearing is a rolling bearing mounted on an electric vertical take-off and landing aircraft that flies by rotation of a plurality of drive units each having a rotor and a motor that rotates the rotor, and that rotatably supports a rotating shaft of the drive unit.

7. a plurality of driving units each having a rotor and a motor for rotating the rotor; The bearing abnormality diagnosis system according to claim 6, further comprising a bearing that rotatably supports a rotation shaft of the drive unit; An electric vertical take-off and landing aircraft equipped with

Images