Data gathering apparatus and data gathering system

Abstract

Provided is a data gathering apparatus that makes it possible to efficiently acquire transmission data from a wireless-sensor-equipped bearing. This data gathering apparatus comprises: a first data communication unit that receives and accumulates data transmitted from a wireless device of a wireless-sensor-equipped bearing, and communicates with the wireless device of the wireless-sensor-equipped bearing, the wireless-sensor-equipped bearing having an outer race, an inner race, a generator, a sensor, and the wireless device; a data accumulation unit that accumulates the data; and a control unit that controls operation of the first data communication unit and the data accumulation unit, the control unit having a plurality of data acquisition patterns that can be selected according to the communication state of the wireless device, and acquiring and accumulating data transmitted by the wireless device of the wireless-sensor-equipped bearing in accordance with conditions of acquisition and accumulation of data that are set in advance for a selected data acquisition pattern.

Description

Data collection device and data collection system Related Applications

[0001] This application claims priority from Japanese Patent Application No. 2024-050335, filed March 26, 2024, the entire contents of which are incorporated herein by reference.

[0002] The present invention relates to a data collection device and a data collection system that collect communication data from electronic components, such as bearings with wireless sensors that perform data communication.

[0003] A bearing with a wireless sensor is known, in which an electronic circuit board including a generator, detection sensor, wireless device for wireless transmission processing, and control circuit is mounted so that it does not protrude from a standard bearing. Patent Document 1 discloses a bearing with a wireless sensor. The bearing with a wireless sensor is incorporated into the rotating part of equipment at manufacturing sites and the like to monitor the equipment's condition. This makes it possible to avoid unexpected equipment shutdowns at manufacturing sites, power generation facilities, infrastructure facilities, and the like, and to improve operation rates through planned maintenance and part replacement.

[0004] A bearing with a wireless sensor, for example, has a generator and an electronic circuit board mounted on one end of a bearing used for inner ring rotation. A stator is fixed to the outer ring of the bearing, and the stator holds a coil. A magnetic ring with alternating north and south poles is fixed to the inner ring of the bearing as a rotor. As the inner and outer rings of the bearing rotate relative to each other, electromagnetic induction generates an AC voltage in the coil. The electronic circuit board, which contains various circuits, sensors, and wireless devices, is fixed to the outer ring of the bearing via the stator and further sealed with an electronic circuit protection material. The AC voltage generated by the generator is input to a power supply circuit. The power supply circuit rectifies the AC voltage to DC, and a voltage limiting circuit reduces any excess voltage to a predetermined voltage. A buck-boost DC-DC converter then generates the constant voltage required for the sensor and wireless module to operate. The sensors, such as acceleration sensors and temperature sensors, are driven at a constant voltage to obtain sensor signals indicating the bearing's status, such as acceleration and temperature. The rotational speed is obtained by processing the generator's AC output. For example, rotational speed information can be obtained from the AC output's alternating frequency and peak voltage.

[0005] The acquired sensor signal and rotational speed data are transmitted via radio waves from a wireless device, for example, according to a standard such as Bluetooth Low Energy (2.4 GHz). The transmitted sensor signal can be switched between multiple pre-set modes, such as monitoring mode and analysis mode, depending on the application. For example, monitoring mode assumes continuous monitoring, acquiring and transmitting temperature, effective acceleration value, and rotational speed at 0.1-second intervals. In analysis mode, a predetermined number of samples of acceleration data are acquired and transmitted so that frequency analysis can be performed on the receiving side. The transmitted data is received by a data collection device such as a PC. When continuously monitoring equipment status over a long period of time, the received data becomes large, so a configuration that communicates with a device with a large data storage capacity (a data logger) and reads the data on a PC or other device is desirable. On the other hand, when a tablet or PC is brought to the site to check the equipment status on an ongoing basis, a configuration that communicates directly with the tablet or PC is effective.

[0006] JP 2017-72170 A

[0007] The wireless sensor-equipped bearing described in Patent Document 1 includes a generator and an electronic circuit board, as described above. The generator generates electricity through the mutual or relative rotation of the inner and outer rings of the bearing, driving the mounted electronic circuits, sensors, and wireless devices, and transmits the obtained sensor signal and rotational speed data via the wireless device. Therefore, unless the rotational speed of the rotating ring exceeds a certain value, the power required to drive the mounted electronic circuits cannot be generated, and data is not transmitted. In this case, when data is acquired and confirmed on-site using a tablet or other device, a wait time occurs until the data can be transmitted. Furthermore, if the rotational speed of the equipment changes irregularly depending on other equipment or the surrounding environment, the timing of data transmission cannot be predicted, resulting in similar wait times and inefficiency. Furthermore, if the rotational speed of the equipment is approximately constant, when a tablet or other device is brought to the site to check data changes over time, the received data becomes large, making data processing cumbersome and inefficient.

[0008] SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a data collection device and a data collection system that can efficiently acquire data transmitted from a bearing with a wireless sensor, in order to solve the above-mentioned problems of the conventional technology.

[0009] Generally, the data collection device of the present invention has multiple data acquisition patterns that can be selected depending on, for example, the communication status of the wireless sensor-equipped bearing, and acquires and stores data transmitted by the wireless sensor-equipped bearing. In the case of a communication status in which the rotational speed of the rotating part of the equipment incorporating the wireless sensor-equipped bearing fluctuates and communication connection and disconnection occurs repeatedly, data is acquired and stored only when communication is possible. Furthermore, when communication is possible, data is acquired and stored only when the rotational speed value is within a predetermined range. In the case of a communication status in which constant communication is possible, data is acquired and stored using a data acquisition pattern with preset acquisition and non-acquisition periods. The data acquisition pattern is selected by the operator or automatically selected depending on the communication status.

[0010] The data accumulation device of the present invention is a data accumulation device that receives and stores data transmitted from a wireless device of a bearing with a wireless sensor, the bearing having an outer ring, an inner ring, a generator, a sensor, and a wireless device, and comprises a first data communication unit that communicates with the wireless device of the bearing with a wireless sensor, a data storage unit that stores the data acquired from the wireless device, and a control unit that controls the operation of the first data communication unit and the data storage unit, wherein the control unit has a plurality of data acquisition patterns that can be selected depending on the communication status of the wireless device, and performs the operation of acquiring and storing the data transmitted by the wireless device of the bearing with a wireless sensor in accordance with the data acquisition and storage conditions that are preset in the selected data acquisition pattern.

[0011] The communication state of the wireless device refers to, for example, a state in which the communication is connected or disconnected, or a state in which the communication is always connected (stable state). Furthermore, the relative rotation between the inner ring and the outer ring refers to one of the inner ring and the outer ring being a fixed ring, and the other rotating relative to the fixed ring. Here, for example, the bearing with wireless sensor is a radial ball bearing, and the wireless sensor may be built into the bearing or attached externally to the bearing after installation, or the wireless sensor may even be located near the bearing. The wireless device may also be replaced with a wired configuration. In this case, the sensor does not need to be a wireless sensor. Examples of the above-mentioned bearing with wireless sensor include the following bearing devices: a magnetic ring fixed to either the outer ring or the inner ring; a stator arranged to face the magnetic ring in the radial direction of the bearing and fixed to the other of the outer ring or the inner ring; and a circuit board, wherein the magnetic ring and the stator form a generator that generates AC power, and the circuit board includes at least one sensor that detects a state of the bearing, a wireless communication circuit that wirelessly transmits an output of the at least one sensor to the outside, and a power supply circuit that converts the AC power generated by the generator into DC power that can be used by the at least one sensor and the wireless communication circuit.

[0012]

[0013] A data accumulation system according to the present invention comprises: a wireless sensor bearing including an outer ring, an inner ring, a generator, a sensor, and a wireless device, wherein the generator generates power to be consumed by the sensor and the wireless device through relative rotation between the inner ring and the outer ring, and the wireless device transmits data output by the sensor; and a data accumulation device that receives and stores the data transmitted by the wireless device, the data accumulation device comprising: a first data communication unit that communicates with the wireless device of the wireless sensor bearing, a data storage unit that stores the data acquired from the wireless device, and a control unit that controls operation of the first data communication unit and the data storage unit, wherein the control unit has a plurality of data acquisition patterns that can be selected according to the communication status of the wireless device, and acquires and stores the data transmitted by the wireless device of the wireless sensor bearing in accordance with conditions for acquisition and storage that are preset for the selected data acquisition pattern. In the above data accumulation device and data accumulation system, the data accumulation device may comprise a second data communication unit that communicates with an external terminal.

[0013] The data accumulation device and data accumulation system according to the present invention have a plurality of selectable data acquisition patterns, and set (or switch) the data acquisition pattern according to the communication status of the wireless sensor-equipped bearing (or the wireless device included therein) to acquire and store the data transmitted by the wireless device, so that even if the rotational speed of the equipment fluctuates, it is possible to efficiently acquire data transmitted by the wireless sensor-equipped bearing at the site, etc., eliminating waiting times when workers acquire data and improving workability. Furthermore, even if the rotational speed of the equipment is approximately constant, it is possible to set (or switch) the data acquisition pattern according to the communication status to acquire and store the data transmitted by the wireless device, making it possible to efficiently acquire data transmitted by the wireless sensor-equipped bearing and dealing with increasingly complicated data processing.

[0014] When the communication state of the wireless sensor bearing with the wireless device is such that the rotational speed of the inner ring and the outer ring relative to each other fluctuates and communication is repeatedly connected and disconnected, the data transmitted by the wireless device may be acquired and stored only when communication is possible. In the above case, the data transmitted by the wireless device of the wireless sensor bearing may be acquired and stored when the rotational speed when communication is possible is within a preset rotational speed range, or by referring to the data output by the sensor when communication is possible. As a result, when the rotational speed of the equipment fluctuates, it is possible to efficiently acquire (and store) data transmitted by the wireless sensor bearing at a site, etc., eliminating waiting times for workers to acquire data at the site and improving workability.

[0015] When the communication state of the wireless sensor bearing with the wireless device is a state in which constant communication is possible, the operation of acquiring and storing the data transmitted by the wireless device of the wireless sensor bearing may be performed by repeating preset acquisition periods and non-acquisition periods by switching with reference to time information or the data output by the sensor. As described above, when the rotational speed of the equipment is approximately constant, it is possible to efficiently acquire (and store) the data transmitted by the wireless sensor bearing, improving the problem of data processing becoming cumbersome and workability becoming poor due to the large volume of received data.

[0016] The data acquisition pattern may be automatically switched based on preset conditions in accordance with the communication state between the wireless sensor-equipped bearing and the wireless device, and the data transmitted by the wireless device may be acquired and stored. By automatically switching the data acquisition pattern, even if the rotation speed of the equipment fluctuates, for example, it becomes possible to efficiently acquire and store the data transmitted by the wireless sensor-equipped bearing at the site, etc., eliminating waiting times for workers when acquiring data and improving workability.

[0017] Any combination of at least two features disclosed in the claims and / or the specification and / or the drawings is included in the present invention. In particular, any combination of two or more of the claims is included in the present invention.

[0018] The present invention will be more clearly understood from the following description of preferred embodiments with reference to the accompanying drawings. However, the embodiments and drawings are merely for illustration and explanation, and should not be used to define the scope of the present invention, which is defined by the appended claims. In the accompanying drawings, the same reference numerals in multiple drawings indicate the same or corresponding parts.

[0019] FIG. 1 is a perspective view showing an example of an entire bearing device used in a data accumulation system of an embodiment; FIG. 2 is a cross-sectional view in a plane including the rotation axis of the bearing of the bearing device; FIG. 3 is a block diagram illustrating the electronic circuit of the bearing device; FIG. 4 is a diagram illustrating a retainer of the bearing device; FIG. 5 is a view of the bearing device as seen from the sensor unit side; FIG. 6 is an exploded perspective view of the sensor unit; FIG. 7 is a diagram illustrating an example of a data accumulation system in which a data accumulation device of an embodiment is installed; FIG. 8 is a block diagram illustrating the configuration of the data accumulation device; FIG. 9 is a waveform diagram illustrating one operation of the data accumulation system; FIG. 10 is a waveform diagram illustrating another operation of the data accumulation system; FIG. 11 is a waveform diagram illustrating still another operation of the data accumulation system; and FIG. 12 is a flow diagram illustrating the automatic switching operation of the data accumulation device.

[0020] One embodiment will be described in detail below with reference to the drawings. In the embodiments described below, when numbers, quantities, etc. are mentioned, the scope of the present disclosure is not necessarily limited to those numbers, quantities, etc., unless otherwise specified. The same reference numerals are used for the same or equivalent parts, and redundant descriptions may not be repeated. It is intended from the beginning that the configurations in the embodiments may be used in appropriate combinations.

[0021] 1 is a perspective view of the entire bearing device 1 (also referred to as a bearing with a wireless sensor or simply a bearing) used in the data collection system of this embodiment. The bearing device 1 includes a bearing 2, a sensor unit 6, and a magnetic ring 7. The bearing 2 includes an outer ring 3 and an inner ring 4. In the bearing 2, for example, the outer ring 3 is a stationary or fixed ring, and the inner ring 4 is a rotating ring. The bearing 2 will be described as a deep groove ball bearing by way of example, but the type of bearing 2 is not limited to a deep groove ball bearing.

[0022] Here, bearing 2 is a standard bearing whose major dimensions (inner diameter, outer diameter, width, etc.) are specified in a specific standard. A standard bearing is a bearing whose dimensions are specified in, for example, ISO or JIS standards. Bearing 2 is a radial bearing, and its major dimensions are those specified in ISO 15 or JIS B1512-1. Hereinafter, bearing 2 will also be referred to as standard bearing 2.

[0023] The sensor unit 6 includes a stator 5 and a lid 14. The structure of the stator 5 will be described in detail later. The lid 14 is a non-metallic resin member that protects the interior of the sensor unit 6. The magnetic ring 7 is a magnetic member magnetized with alternating north and south poles in the circumferential direction. The stator 5 is fixed to the outer ring 3, and the magnetic ring 7 is fixed to the inner ring 4. The magnetic ring 7 may be fixed to either the outer ring 3 or the inner ring 4. The stator 5 is disposed so as to face the magnetic ring 7 in the radial direction of the bearing 2, but may be fixed to the other of the outer ring 3 and the inner ring 4. The stator 5 and the magnetic ring 7 form a generator G that generates AC power. The generator G is a claw-pole type generator, but may be a generator of other structure. The dashed-dotted line in FIG. 1 indicates the rotation axis O of the bearing 2.

[0024] 2A is a cross-sectional view of bearing 2 taken along a plane including rotation axis O. Bearing 2 includes outer ring 3, inner ring 4, rolling elements 8, cage 9, and seal 10. The bearing 2 may be selected from the model sizes of standard bearings in which the distance W between end face 11 of bearing 2 and rolling elements 8 can accommodate sensor unit 6 and magnetic ring 7. End face 11 is also the end face of outer ring 3.

[0025] A stepped first notch 3a is formed in the inner peripheral surface of one end (on the end face 11 side) of the outer ring 3, as a recess at the end of the outer ring 3. A stepped second notch 4a is formed in the outer peripheral surface of one end of the inner ring 4, facing the first notch 3a, as a recess at the end of the inner ring 4. In the axial direction (also referred to as the axial direction) of the bearing 2, an annular space is formed by an annular recess 50 cut out toward the rolling elements 8 by the first notch 3a and the second notch 4a, from the outer ring 3 to the inner ring 4.

[0026] The sensor unit 6 includes a holding member 12, a circuit board 13, a stator 5, and a lid 14. The holding member 12 is made of a magnetic material and has a partition wall 12a that separates the holding member 12 into a first region 12b and a second region 12c in the radial direction (also referred to as the radial direction) of the bearing 2. The circuit board 13 is fixed to an inner bottom surface 12d of the first region 12b, and the stator 5 is disposed in the second region 12c. The lid 14 protects the circuit board 13 fixed to the inner bottom surface 12d. The circuit board 13 may be sealed using a resin sealing material instead of the lid 14.

[0027] The outer diameter surface of the retaining member 12 on the first region 12b side is fitted into and fixed to a first cutout portion 3a formed in the outer ring 3. The retaining member 12 is press-fit or bonded so as not to protrude from the end face 11 of the outer ring 3. The retaining member 12 may be fixed by a combination of press-fitting and bonding, or by other methods. When the retaining member 12 is fixed to the first cutout portion 3a, a certain gap is secured between the rolling elements 8 and the retaining member 12. This gap prevents the rolling elements 8 and the retaining member 12 from coming into contact with each other even when displacement in the axial direction occurs.

[0028] The stator 5 includes two magnetic members 21 and 22, a bobbin 23, and a coil 24. A portion of the holding member 12 including the second region 12c is used as the magnetic member 21 of the stator 5.

[0029] The magnetic ring 7 includes a core 7a and a multi-pole magnet 7b. The multi-pole magnet 7b is formed by, for example, vulcanizing and bonding a magnetic material, which is a mixture of magnetic powder and rubber, to the core 7a, and then magnetizing the N and S poles alternately around the circumferential direction of the bearing 2. The core 7a of the magnetic ring 7 has a flange portion 7c to increase rigidity. The magnetic ring 7 is fixed to the outer diameter surface 4b of the inner ring 4 by press-fitting or the like. The flange portion 7c fits into a second notch portion 4a formed in the inner ring 4. The magnetic ring 7 is positioned so as not to protrude from the end face 20 of the inner ring 4.

[0030] Inside the annular recess 50, the magnetic ring 7, stator 5, and circuit board 13 are arranged so that they do not overlap one another in the axial direction of the bearing 2. This allows each component to be arranged inside the annular recess 50, thereby reducing the dimensions of the bearing 2. Furthermore, in the bearing device 1, for example, the magnetic ring 7 is fixed to the inner ring 4, and the stator 5 is fixed to the outer ring 3 at an opposing position. In this case, the inner ring 4 and the outer ring 3 are subject to smaller axial movement of the bearing 2 than the cage 9, so a stable amount of power generation can be ensured by the generator G, and the bearing device can function normally while keeping its dimensions down.

[0031] The electronic circuit 13 will be described using FIG. 2B. The electronic circuit 13 includes at least a power supply circuit 17 (described below), a wireless communication circuit 18 (a wireless device), and sensors sn (collectively referred to as sensors). The power supply circuit 17 includes at least a rectifier circuit rc, a voltage limiting circuit lm, and a step-up / step-down DC-DC converter CV. The AC voltage generated by the generator G is input to the power supply circuit 17. In the power supply circuit 17, the rectifier circuit rc first rectifies the AC voltage to a DC voltage. The voltage limiting circuit lm then reduces any excess voltage to a predetermined voltage. The step-up / step-down DC-DC converter CV then obtains a constant voltage required for the operation of the sensors and wireless modules, such as the wireless communication circuit 18. The sensors sn include acceleration sensors and temperature sensors, and are driven at a constant voltage to output sensor signals indicating the bearing status, such as acceleration and temperature. The rotational speed of the inner ring (rotating ring) is obtained by processing the generator's AC output (waveform) without using a dedicated sensor. The rotation speed information can be acquired from, for example, the alternating frequency or peak voltage of the AC output. The wireless communication circuit 18 wirelessly transmits the output (measurement data) of the sensor sn to the outside, as will be described later.

[0032] FIG. 3 is a diagram illustrating the retainer 9. The retainer 9 has recesses 93 formed at a predetermined pitch along the circumferential direction of an axial end face 91 of the annular retainer body. A pair of claws 94, 94 are formed to protrude from circumferentially opposing open ends of the recesses 93. The recesses 93 and the pair of claws 94, 94 form a pocket 95 in which the rolling elements 8 shown in FIG. 2A are housed. As described above, the retainer 9 has a shape in which one end face 91 is open and the other end face 92 is connected. The retainer 9 is made of resin, and the sensor unit 6 and the magnetic ring 7 are arranged on the open side so as not to protrude from end faces 11 and 20.

[0033] FIG. 4A is a view of the bearing device 1 from the sensor unit 6 side. In FIG. 4A, part of the lid 14 is omitted so that the interior of the sensor unit 6 can be seen. One or more sensors that monitor the state of the bearing 2 are mounted on the circuit board 13. For example, an acceleration sensor 15 and a temperature sensor 16 are mounted on the circuit board 13. The temperature sensor 16 may be inserted through a hole (not shown) provided on the inner bottom surface 12d of the retaining member 12 and mounted on the back surface of the circuit board 13 so as to be close to (or in contact with) the end face of the first cutout portion 3a of the outer ring 3. This brings the temperature sensor 16 close to the outer ring 3, allowing it to accurately measure the temperature of the bearing 2.

[0034] The circuit board 13 also has a power supply circuit 17 and a wireless communication circuit 18 mounted thereon. The power supply circuit 17 rectifies the AC power generated by the generator G and converts it into DC power. The acceleration sensor 15, the temperature sensor 16, and the wireless communication circuit 18 use the DC power converted by the power supply circuit 17. Terminals 25 are arranged on the circuit board 13.

[0035] The wireless communication circuit 18 includes an antenna portion 18a. The wireless communication circuit 18 wirelessly transmits the outputs of the acceleration sensor 15 and the temperature sensor 16, which monitor the state of the bearing 2, to the outside using the antenna portion 18a. The circuit board 13 is fixed to the holding member 12 with a plurality of screws 19. The circuit board 13 may also be adhesively fixed to the holding member 12. The circuit board 13 on which the wireless communication circuit 18 is mounted is disposed opposite the resin lid 14. This results in a structure in which the wireless communication circuit 18 is not sealed with a conductive material such as metal. This enables wireless communication using the antenna portion 18a in the wireless communication circuit 18.

[0036] 4B is an exploded perspective view of the sensor unit 6. In this figure, the sensor unit 6 includes a holding member 12, a circuit board 13, and a stator 5. The circuit board 13 is fixed to the inner bottom surface 12d of the first region 12b of the holding member 12. The stator 5 is disposed in the second region 12c of the holding member 12. The stator 5 includes two magnetic members 21 and 22, a bobbin 23, and a coil 24. As described above, a portion of the holding member 12 including the partition wall 12a of the second region 12c is used as the magnetic member 21 of the stator 5.

[0037] The magnetic members 21 and 22 have a U-shaped cross section. A plurality of claws 21a are formed on the inner periphery of the magnetic member 21. A plurality of claws 22a are formed on the inner periphery of the magnetic member 22. A coil 24, which is formed by winding a magnet wire multiple times, is placed in a groove formed in the circumferential direction of the bobbin 23. The bobbin 23 may be omitted. The stator 5 is assembled with the bobbin 23, on which the coil 24 is wound, inserted into the magnetic member 22, so that the plurality of claws 21a of the magnetic member 21 and the plurality of claws 22a of the magnetic member 22 are alternately arranged with gaps in the circumferential direction, and the outer periphery 22b of the magnetic member 22 is fixed so as to fit into the inner periphery of the partition wall 12a of the magnetic member 21.

[0038] 5 shows an example of a data collection system sys composed of a wireless sensor bearing 1 and a data collection device 100 of this embodiment. In the figure, the data collection device 100 of this embodiment is installed in equipment 200 that includes the wireless sensor bearing 1. The data collection device of this embodiment generally receives and stores data (measurement data) transmitted from the wireless device of the wireless sensor bearing 1, which has an outer ring 3, an inner ring 4, a generator G, a sensor sn, and a wireless device 18. In the figure, the wireless sensor bearing 1 is incorporated into the rotation support portion of a motor rotor 235, which is the rotating part of a motor 230 on the equipment side.

[0039] The wireless sensor bearing 1 shown in the figure incorporates a generator G and an electronic circuit board 13 carrying a power supply circuit 17, a sensor sn, a wireless device (wireless communication circuit) 18, and other components, as described with reference to FIGS. 2A and 2B. The generator G generates AC voltage through the rotation of the motor rotor 235 (see FIG. 5) and outputs it to the power supply circuit 17. As shown in FIG. 2B, the power supply circuit 17 rectifies the AC voltage to DC voltage using a rectifier circuit rc, and then reduces any excess voltage to a predetermined voltage using a voltage limiting circuit lm. A step-up / step-down DC-DC converter CV then generates a constant voltage necessary for the operation of wireless modules such as the sensor sn and the wireless communication circuit 18. The sensor sn includes an acceleration sensor 15 and a temperature sensor 16, and is driven at a constant voltage to obtain sensor signals such as acceleration and temperature. The rotational speed is obtained by processing the AC output waveform of the generator G.

[0040] The obtained sensor signal and rotation speed data are wirelessly transmitted by the wireless device 18. The transmitted sensor signal can be selected from multiple pre-set modes, such as monitoring mode and analysis mode, depending on the application. For example, monitoring mode assumes continuous monitoring, and acquires and transmits the temperature, effective acceleration value, and rotation speed at 0.1 second intervals. In analysis mode, a predetermined number of samples of acceleration data are acquired and transmitted so that frequency analysis can be performed on the receiving side. The transmitted data is received by an external terminal such as a PC or mobile device.

[0041] The bearing with wireless sensor (bearing device) 1 shown in FIG. 1 has a structure in which the generator and the electronic circuit board 13 carrying the circuits, sensor sn, and wireless device 18 are built in, but these may also be arranged outside the bearing. For example, the electronic circuit board 13 and generator G may be arranged axially outside the bearing and fixed in place as an integrated structure.

[0042] As shown in Figure 5, an opening 250 having a space communicating between the wireless sensor bearing 1 and the outside of the facility 200 is provided in the facility 200 so as to enable wireless communication between the wireless sensor bearing 1 and the data collection device 100. In the facility 200, the data collection device 100 is installed in a position around the opening 250 where radio waves can be transmitted and received. Although the facility 200 in Figure 5 has an opening 250, even if an opening 250 is not provided, a built-in antenna (not shown) that wirelessly communicates with the wireless sensor bearing 1 may be installed near the wireless sensor bearing 1 so that the wireless sensor bearing 1 and the data collection device 100 can communicate wirelessly, and the built-in antenna may be connected to a transmitting antenna installed outside the facility 200 so that the transmitting antenna communicates wirelessly with the data collection device 100.

[0043] FIG. 6 shows the configuration of the data accumulation device 100 of this embodiment. The data accumulation device 100 includes a (first) data communication unit 120 that wirelessly communicates with the wireless sensor-equipped bearing 1, a data storage unit 140 that stores data acquired from the wireless sensor-equipped bearing 1, a setting operation unit 130 that serves as an input / output unit through which an operator can change device settings and set data acquisition patterns, and a control unit 110 that performs overall control, including controlling the operation of these units. Additionally, the data accumulation device 100 may include a (second) data communication unit 150 that communicates with an external terminal 300 that an operator uses to collect data. The data accumulation device 100 is powered by an internal power source, such as a battery (not shown), or an external power supply. While the first data communication unit 120 and the second data communication unit 150 are separated into two units for easy understanding of their functions, they may also be configured as a single wireless function unit.

[0044] The operation of the data accumulation device 100 when it receives and stores data from the wireless sensor bearing 1 will be described. The wireless sensor bearing 1 wirelessly transmits the acquired sensor signal and rotational speed via the wireless communication circuit (wireless device) 18, which is received by the first data communication unit 120 of the data accumulation device 100. The first data communication unit 120 outputs the sensor signal and rotational speed to the control unit 110. The control unit 110 assigns a date and time (data reception date and time) to the sensor signal and rotational speed data, and saves and accumulates the data as data in the data accumulation unit 140. Here, the data refers to substantially the same thing as the sensor signal and rotational speed, but may also include data on the data reception date and time. In this embodiment, the data saved and accumulated in the data accumulation unit 140 is primarily referred to as data.

[0045] The data acquisition and storage operations (for example, both acquisition and storage, acquisition but no storage, or neither acquisition nor storage) are performed according to the data acquisition and storage conditions set in advance in a data acquisition pattern (in this embodiment, one of data acquisition patterns A to C described later). Data acquisition patterns A to C are set by the operator using the setting operation unit 130 according to the communication state between the wireless sensor-equipped bearing 1 and the data accumulation device 100, or are set automatically by the control unit 110 as described later. The communication state refers to, for example, a state in which the communication is connected or disconnected, or a state in which the communication is always connected (stable state). Note that the communication state may also include a state in which the communication is always disconnected. The communication state is notified to the operator by any notification means.

[0046] Data acquisition patterns A to C will now be described. Data acquisition pattern A is a data acquisition pattern in a communication state in which wireless communication repeatedly connects and disconnects. The wireless sensor bearing 1 generates power and performs wireless communication through the rotation of the motor rotor 235, which is the rotating part of the equipment 200. Therefore, the generator G of the wireless sensor bearing 1 must rotate at a certain rotational speed (ω1) or higher to generate enough power to drive the sensor, wireless module, etc. When constantly rotating at a rotational speed ω1 or higher, the wireless sensor bearing 1 maintains a state in which sensor signals and rotational speed can be communicated. However, if the rotational speed of the rotating part fluctuates, communication repeatedly connects and disconnects across the rotational speed ω1 depending on the magnitude of the rotational speed. Figure 7 shows an example of this rotational speed. When the rotational speed fluctuates, the sensor, wireless module, etc. can be driven at rotational speeds ω1 or higher, so data (sensor signals and rotational speed) are transmitted in the time periods t2 to t3 and t8 to t9. On the other hand, in the time periods t1 to t2, t3 to t8, and t9 to t10 (the periods shown in gray in FIG. 7), the rotational speed is less than ω1, so the generated power is insufficient and communication is not possible. In this case, the data accumulation device 100 can acquire data (sensor signal and rotational speed) from the wireless sensor-equipped bearing 1 only in the time periods t2 to t3 and t8 to t9. Meanwhile, in the rotational speed periods shown in the figure with solid lines (periods that are not gray in FIG. 7), the data accumulation device 100 can acquire rotational speed data, but in the rotational speed periods shown in the dashed lines (periods shown in gray in FIG. 7), the data accumulation device 100 cannot acquire rotational speed data.

[0047] Data acquisition pattern B is a pattern that adds an additional condition for data accumulation to the conditions of data acquisition pattern A. FIG. 8 shows an example in which data including a sensor signal, rotation speed, and date (data reception date) is accumulated when the rotation speed is equal to or greater than ω2. The solid-line sections of rotation speed data in the figure (sections ta to tb, tc to td) indicate cases in which data is accumulated, while the dashed-dotted sections (sections t2 to ta, tb to t3, t8 to tc, td to t9) indicate cases in which the sensor signal and rotation speed are acquired but the data is not accumulated. In the sections shown by the solid lines, the rotation speed data, the sensor signal, and the date data are accumulated. While FIG. 8 shows a condition for data accumulation when the rotation speed is equal to or greater than ω2, the condition for data accumulation may also be set to a range between rotation speeds equal to or greater than ω2 and rotation speeds equal to or less than ω3. In addition to referring to the rotation speed as described above, the condition for data accumulation may also be set by referring to data output by the sensor when communication is possible. In this case, for example, when the value of a sensor signal from one sensor during communication is above or below a predetermined threshold, data on the sensor signal, rotation speed, and date may be stored.

[0048] Data acquisition pattern C is a data acquisition pattern in a communication state where wireless communication is always possible. Because data is always available, accumulating all data would result in a huge amount of data. Therefore, as shown in FIG. 9 , data acquisition periods TA (sensor signal and rotation speed) are alternately repeated with periods TB (not shown) during which data is not acquired, according to time information referenced, for example, by a timer (not shown). The solid-line sections (ta-tb, tc-td, te-tf) of the rotation speed data (graph) in the figure indicate acquired and accumulated data, while the dashed-dotted sections (0-ta, tb-tc, td-te, tf-) indicate data that could be acquired but not accumulated. In the solid-line sections, date data is accumulated along with rotation speed data and sensor signal data. In addition to referencing the time information described above, data output by the sensor may also be referenced to set conditions for alternating periods TA (data acquisition periods TA) and periods TB (not data acquisition periods TB). For example, when the value of a sensor signal from one sensor exceeds or falls below a predetermined threshold, periods TA and TB may be switched from one to the other, or from the other to the one, or even alternately.

[0049] The control unit 110 may automatically switch between data acquisition patterns A to C depending on the communication status. An operational flow for this automatic switching is shown in FIG. 10 . If communication does not repeatedly connect and disconnect (NO in step S100), data acquisition pattern C is set (step S200). Here, by returning to step S100 and looping only in this case, it is possible to switch to data acquisition pattern A or B if communication becomes unstable due to a change in the rotation pattern of the equipment 200 or a change in the radio wave environment of the data accumulation device 100. That is, if communication repeatedly connects and disconnects (YES in step S100) and there is no rotation speed condition for data accumulation (YES in step S300), data acquisition pattern A is set (step S400). If there is a rotation speed condition for data accumulation (NO in step S300), data acquisition pattern B is set (step S500), and the flow ends.

[0050] If the wireless sensor-equipped bearing 1 has a function for switching modes such as monitoring mode and analysis mode, the mode can be switched by outputting a mode setting command from the control unit 110 to the first data communication unit 120, and then transmitting the mode setting command from the first data communication unit 120 to the wireless sensor-equipped bearing 1. For example, in the case of data acquisition pattern C shown in Fig. 9, it becomes possible to perform operations such as automatically switching modes after acquiring data a specified number of times within the data acquisition period TA, which has the effect of improving operability.

[0051] Next, the operation will be described for the case where the data accumulating device 100 transmits data to the external terminal 300 of Fig. 6. In this case, the (second) data communication unit 150 is used. When an operator transmits a data transmission request command from the external terminal 300 to the data accumulating device 100, the data accumulating device 100 receives the request command via the second data communication unit 150 and outputs it to the control unit 110. Upon receiving the request command, the control unit 110 acquires the sensor signal, rotation speed, and date and time data from the data accumulation unit 140 and outputs them to the second data communication unit 150. The second data communication unit 150 wirelessly transmits the data received from the control unit 110 to the external terminal 300.

[0052] As described above, the preferred embodiment has been described with reference to the drawings, but various additions, modifications, and deletions can be made without departing from the spirit of the present invention. Therefore, such additions, modifications, and deletions are also included in the scope of the present invention.

[0053] DESCRIPTION OF SYMBOLS 1 Bearing device (bearing with wireless sensor) 3 Outer ring 4 Inner ring 18 Wireless communication circuit (wireless device) 100 Data accumulating device 110 Control unit 120 (first) data communication unit 140 Data storage unit 150 (second) data communication unit 300 External terminal G Generator sn Sensor sys Data accumulation system

Claims

1. A data accumulation device that receives and stores data transmitted from a wireless device of a wireless sensor-equipped bearing having an outer ring, an inner ring, a generator, a sensor, and a wireless device, the data accumulation device comprising: a first data communication unit that communicates with the wireless device of the wireless sensor-equipped bearing; a data accumulation unit that accumulates the data acquired from the wireless device; and a control unit that controls the operation of the first data communication unit and the data accumulation unit, wherein the control unit has a plurality of data acquisition patterns that can be selected according to the communication status of the wireless device, and performs operations to acquire and accumulate the data transmitted by the wireless device of the wireless sensor-equipped bearing in accordance with the data acquisition and accumulation conditions that are preset in the selected data acquisition pattern.

2. A data accumulation device as set forth in claim 1, wherein, when the communication state between the bearing with wireless sensor and the wireless device is such that the relative rotational speed between the inner ring and the outer ring fluctuates and communication is repeatedly connected and disconnected, the data transmitted by the wireless device is acquired and stored only when communication is possible.

3. A data collection device according to claim 2, wherein when the rotational speed when communication is possible is within a preset rotational speed range, or when the data output by the sensor when communication is possible is referenced, the data collection device acquires and stores the data transmitted by the wireless device of the bearing with wireless sensor.

4. A data accumulation device as claimed in claim 1, wherein, when the communication state of the bearing with wireless sensor and the wireless device is one in which constant communication is possible, the data accumulation device acquires and stores the data transmitted by the wireless device of the bearing with wireless sensor by repeating preset acquisition and non-acquisition periods by switching based on time information or the data output by the sensor.

5. A data accumulation device according to claim 1, which automatically switches the data acquisition pattern based on preset conditions in accordance with the communication state between the wireless sensor-equipped bearing and the wireless device, and performs operations of acquiring and storing the data transmitted by the wireless device.

6. A data collection device according to claim 1, comprising a second data communication unit for communicating with an external terminal.

7. A data accumulation system comprising: a wireless sensor bearing comprising an outer ring, an inner ring, a generator, a sensor, and a wireless device, wherein the generator generates power to be consumed by the sensor and the wireless device through the relative rotation of the inner ring and the outer ring, and the wireless device transmits data output by the sensor; and a data accumulation device that receives and stores the data transmitted by the wireless device, the data accumulation device comprising a first data communication unit that communicates with the wireless device of the wireless sensor bearing, a data storage unit that stores the data acquired from the wireless device, and a control unit that controls the operation of the first data communication unit and the data storage unit, wherein the control unit has a plurality of data acquisition patterns that can be selected in accordance with the communication status of the wireless device, and performs operations to acquire and store the data transmitted by the wireless device of the wireless sensor bearing in accordance with the data acquisition and storage conditions that are preset for the selected data acquisition pattern.

Images