JP2024017087A - Detection device and detection method - Google Patents

Abstract

The present invention provides a detection device capable of detecting the attachment state of a fastening member that fastens a rotating body such as a wheel. A sensor device 100 (detection device) includes a magnetic sensor 21 (sensor unit) and a signal processing unit 302 (state detection unit) that detects the fastening state of a nut 240 (fastening member) based on a detection signal of the magnetic sensor 21. section). The magnetic sensor 21 detects distortion of the link member 10 due to rotation of the nut 240 connected by the link member 10. The signal processing unit 302 detects the fastening state of the nut 240 based on the distortion of the link member 10 detected by the magnetic sensor 21. [Selection diagram] Figure 3

Description

The present disclosure relates to a detection device and a detection method.

Japanese Patent Laid-Open No. 2005-329907 (Patent Document 1) discloses a detection method that detects the mounting state of a tire (a nut for fastening a wheel) based on a detected value of a detector (G sensor) attached to the tire or wheel. An apparatus is disclosed.

Japanese Patent Application Publication No. 2005-329907

By the way, in a device that detects the attachment state of a tire (a fastening member that fastens a wheel), there is a desire for a technique that more easily detects the attachment state of the tire (a fastening member that fastens a wheel).

The present disclosure has been made to solve such problems, and an object of the present disclosure is to provide a detection device and a detection method that can detect the attachment state of a fastening member that fastens a rotating body such as a wheel. It is to be.

A detection device according to a first aspect of the present disclosure is a detection device that detects distortion of a link member that connects at least two fastening members among a plurality of fastening members that fasten a predetermined member to a fastened member, A sensor unit detects distortion of the link member due to rotation of at least one of the two fastening members, and detects a fastening state of the at least one fastening member based on the distortion of the link member detected by the sensor unit. and a state detection unit.

In the detection device according to the first aspect of the present disclosure, as described above, the fastening state of at least one of the plurality of fastening members is detected based on the distortion of the link member detected by the sensor section. Here, while the distortion of the link member changes depending on the rotation amount (looseness amount) of the fastening member, it does not change depending on the type or size of the fastened member. Therefore, the fastening state (attached state) of the fastening member can be easily detected based on the distortion of the link member.

A detection method according to a second aspect of the present disclosure is a detection method for detecting distortion of a link member connecting at least two fastening members among a plurality of fastening members fastening a predetermined member to a fastened member, the detection method comprising: a step of detecting distortion of a link member due to rotation of at least one fastening member of the two fastening members; and a step of detecting a fastening state of at least one fastening member based on the detected distortion of the link member. Be prepared.

In the detection method according to the second aspect of the present disclosure, as described above, the fastening state of at least one of the plurality of fastening members is detected based on the distortion of the link member detected by the sensor section. Thereby, it is possible to provide a detection method that can easily detect the fastening state (attached state) of the fastening member based on the distortion of the link member.

According to the present disclosure, it is possible to detect the attachment state of a fastening member that fastens a rotating body such as a wheel.

1 is a diagram showing a vehicle equipped with sensor devices according to first and second embodiments; FIG. FIG. 3 is a cross-sectional view of a nut according to the first and second embodiments. It is a figure showing a link member and a sensor device by a 1st embodiment. FIG. 1 is a diagram showing the configuration of a sensor device according to a first embodiment. FIG. 3 is a partially enlarged view showing the vicinity of the sensor device in a state where the link member is distorted. FIG. 3 is a flow diagram showing a control flow of the sensor device according to the first embodiment. It is a figure which shows the link member and sensor device by 2nd Embodiment. FIG. 3 is a diagram showing the configuration of a sensor device according to a second embodiment. FIG. 7 is a flow diagram showing a control flow of a sensor device according to a second embodiment.

Embodiments of the present disclosure will be described in detail below with reference to the drawings. In addition, the same reference numerals are attached to the same or corresponding parts in the drawings, and the description thereof will not be repeated.

[First embodiment]
FIG. 1 is a diagram showing a vehicle 200 on which a sensor device 100 (see FIG. 3) according to the first embodiment is mounted. Vehicle 200 includes a plurality of wheels 210. The vehicle 200 also includes a communication terminal 201 that is capable of communicating with a communication section 23 described below and includes a display section (not shown). Note that the sensor device 100 is an example of a "detection device" of the present disclosure.

Wheel 210 includes a wheel 220 and a tire 230 attached to wheel 220. The wheel 220 is fastened to a wheel hub 250a (see FIG. 2) with a plurality of (six in FIG. 1) nuts 240. Nut 240 rotates in the tightening direction (clockwise) and loosening direction (counterclockwise). Note that the number of nuts 240 is not limited to the above example. Note that the wheel 220 and the wheel hub 250a are examples of a "fastened member" and a "predetermined member" of the present disclosure, respectively. Further, the nut 240 is an example of a "fastening member" of the present disclosure.

As shown in FIG. 2, the nut 240 fastens the bolt 250 to the wheel 220. Specifically, the wheel 220 is provided with a plurality of (six) wheel holes 221 into which bolts 250 are inserted (penetrated). The nut 240 fastens the bolt 250 inserted into the wheel hole 221 to the wheel 220. Note that the bolt 250 is fixed to the wheel hub 250a. Note that a washer 241 may be provided between the nut 240 and the wheel 220.

FIG. 2 shows an example of a double tire, where the wheel 220 consists of an inner wheel 222 and an outer wheel 223. The nut 240 is open on one side.

Moreover, as shown in FIG. 3, two nuts 240 adjacent to each other among the six nuts 240 are connected by the link member 10. The link member 10 is made of elastic resin.

The link member 10 includes a pair of fitting portions 11 provided with fitting holes 11a into which nuts 240 are fitted. Further, the link member 10 includes a connecting portion 12 that connects the pair of fitting portions 11 to each other. Note that the connecting portion 12 has a Z-shape due to the provision of two bent portions.

Further, the sensor device 100 includes a sensor chip 20 and a magnet 30. The sensor chip 20 is attached to the outer surface 11b of one fitting portion 11 of the link member 10. Magnet 30 is attached to connecting portion 12 . The magnet 30 is attached to the surface 12a of the connecting portion 12 that faces the sensor chip 20. Note that the sensor chip 20 may be provided on the outer surface 11b of each of the two fitting portions 11 of the link member 10.

As shown in FIG. 4, the sensor chip 20 includes a magnetic sensor 21, a signal processing section 22, a communication section 23, and a power supply section 24. Note that the magnetic sensor 21 and the signal processing section 22 are examples of a "sensor section" and a "state detection section" of the present disclosure, respectively.

The magnetic sensor 21 detects the magnitude of magnetic flux (amount of magnetic flux) from the magnet. The signal processing unit 22 detects the state (fastened state) of the nut 240 based on the detection signal of the magnetic sensor 21.

The communication unit 23 transmits the processing result of the signal processing unit 22 or information based on the processing result to the communication terminal 201 (see FIG. 1) of the vehicle 200 by wireless communication. The power supply section 24 supplies power to each of the magnetic sensor 21, the signal processing section 22, and the communication section 23.

Here, the magnetic sensor 21 detects distortion of the link member 10 due to rotation of the nut 240 connected by the link member 10. Specifically, as shown in FIG. 5, when the nut 240 rotates, the link member 10 is distorted, and the distance D between the sensor chip 20 and the magnet 30 changes. The magnetic sensor 21 detects distortion of the link member 10 based on a change in the distance D. In the example shown in FIG. 5, the distance D between the sensor chip 20 and the magnet 30 is reduced by rotating the nut 240 on the fitting part 11 side to which the sensor chip 20 is attached in the loosening direction (counterclockwise). It's getting smaller.

As a result, the magnet 30 approaches the sensor chip 20 (magnetic sensor 21), so the number of magnetic fluxes from the magnet 30 passing through the magnetic sensor 21 increases. As a result, the magnitude of the magnetic flux (magnetic flux amount) detected by the magnetic sensor 21 increases. Note that the change in the magnitude of the magnetic flux described above is an example of "predetermined information" of the present disclosure.

The signal processing unit 22 acquires the detection value of the magnetic sensor 21 at predetermined intervals (for example, every 20 seconds to 120 seconds).

Further, the signal processing unit 22 detects the fastening state of the nut 240 based on the difference between the amount of magnetic flux detected by the magnetic sensor 21 this time and the amount of magnetic flux detected by the magnetic sensor 21 up to the previous time. If the difference is outside a predetermined tolerance, the signal processing unit 22 determines that the nut 240 is loose (not fixed). In this case, the signal processing section 22 notifies the communication terminal 201 (see FIG. 1) through the communication section 23 (see FIG. 4) that the nut 240 is loosened. As a result, a warning may be displayed on a display unit (not shown) of the communication terminal 201, or the communication terminal 201 may generate an alarm sound. On the other hand, the signal processing unit 22 determines that the nut 240 is fixed if the difference is within a predetermined tolerance range. In this case, the signal processing unit 22 does not notify the communication terminal 201. Further, the amount of magnetic flux detected up to the previous time may be the amount of magnetic flux of the previous time, or may be the average value of the amount of magnetic flux of the past several times including the previous time.

The signal processing unit 22 also acquires information on the initial value of the detection value (magnetic flux amount) of the magnetic sensor 21. The signal processing unit 22 acquires the initial value based on, for example, pressing a predetermined button 201a (see FIG. 1) of the communication terminal 201. Specifically, the signal processing unit 22 sets the detected value (magnetic flux amount) of the magnetic sensor 21 at the time the button is pressed as an initial value. Note that the button 201a is preferably pressed down, for example, when the tire 230 (wheel 220) is attached to the wheel hub 250a and the nut 240 is fastened with a predetermined tightening torque. Furthermore, the sensor device 100 may be provided with a button having the function of the button 201a described above. Further, the communication unit 23 of the sensor device 100 may be capable of bidirectional communication with the ECU of the vehicle 200. In this case, the information on the initial value may be stored in the signal processing section 22.

Further, the signal processing unit 22 detects the fastening state of the nut 240 based on the difference between the current detection value (magnetic flux amount) of the magnetic sensor 21 and the above-mentioned initial value. Specifically, the signal processing unit 22 determines that the nut 240 is loose (not fixed) when the difference is outside a predetermined tolerance range. In this case, the signal processing section 22 notifies the communication terminal 201 (see FIG. 1) that the nut 240 is loosened through the communication section 23 (see FIG. 4). As a result, a warning may be displayed on a display unit (not shown) of the communication terminal 201, or the communication terminal 201 may generate an alarm sound.

Further, the signal processing unit 22 controls the nut 240 when the amount of change in the magnetic flux detected by the magnetic sensor 21 (corresponding to the “value based on the amount of distortion of the link member” in the present disclosure) is equal to or greater than a predetermined threshold. Detects the fastening state of the Specifically, the signal processing unit 22 controls the nut 240 when the amount of change in the magnetic flux detected by the magnetic sensor 21 continues to be equal to or greater than a predetermined threshold for a predetermined period of time or longer (for example, one minute or longer). Detects the fastening state of the Note that the predetermined threshold value is, for example, the amount of change in magnetic flux that corresponds to a case where (slight) distortion occurs in the link member 10 due to vibration, sudden acceleration (sudden deceleration), etc. of the vehicle 200, The information may be stored in advance in a storage device (not shown) or the like.

(Control flow of sensor device)
Next, an example of the control flow of the sensor device 100 will be described with reference to FIG. 6. First, in step S1, the amount of magnetic flux from the magnet 30 is detected by the magnetic sensor 21. Next, in step S2, the signal processing unit 22 acquires information on the detected amount of magnetic flux from the magnetic sensor 21.

Next, in step S3, the signal processing unit 22 detects the fastening state of the nut 240 based on the information on the amount of magnetic flux acquired in step S2. If it is detected that the nut 240 is loose (Yes in S3), the process proceeds to step S4. Furthermore, if it is detected that the nut 240 is not loose (No in S3), the process returns to step S1. As described above, the detection of the fastened state based on the amount of magnetic flux is performed based on the difference from the previously detected value or the initial value.

Then, in step S4, the signal processing unit 22 notifies the communication terminal 201 through the communication unit 23 that the nut 240 is loose.

As described above, in the first embodiment, the fastened state of the nut 240 is detected based on the distortion of the link member 10 detected by the magnetic sensor 21. Thereby, the fastening state of the nut 240 can be detected based on the detection result of the magnetic sensor 21, regardless of the size and type of the wheel 220 as well as the speed of the vehicle 200.

[Second embodiment]
Next, a second embodiment of the present disclosure will be described. In the second embodiment, a strain gauge 301 is used, unlike the first embodiment described above, in which the magnetic sensor 21 is used. Note that the same components as in the first embodiment are given the same reference numerals and will not be repeatedly described.

As shown in FIG. 7, the sensor device 300 is attached to the connecting portion 12 of the link member 10. Specifically, the sensor device 300 is attached to a strained portion 12c of the connecting portion 12 of the link member 10 that is distorted (flexed) when the nut 240 rotates in the loosening direction. The distorted portion 12c is an example of a "portion where distortion occurs" in the present disclosure.

As shown in FIG. 8, the sensor device 300 includes a strain gauge 301, a signal processing section 302, a communication section 303, and a power supply section 304. Note that the strain gauge 301 and the signal processing section 302 are examples of a "sensor section" and a "state detection section" of the present disclosure, respectively.

The strain gauge 301 detects a change in the electrical resistance value (hereinafter referred to as resistance value) of the strained portion 12c. The resistance value of the strained portion 12c changes because the cross-sectional area of the strained portion 12c changes as the strained portion 12c is distorted. For example, when the nut 240 shown in FIG. 7 is rotated in the loosening direction, the strained portion 12c is deformed to be elongated (that is, its length increases), and the cross-sectional area of the strained portion 12c becomes smaller. This increases the resistance value of the strained portion 12c.

The signal processing unit 302 detects the state (fastened state) of the nut 240 based on the change in the resistance value of the link member 10 detected by the strain gauge 301. Note that the change in the resistance value of the link member 10 is an example of "predetermined information" of the present disclosure.

The communication unit 303 transmits the processing result of the signal processing unit 302 or information based on the processing result to the communication terminal 201 (see FIG. 1) of the vehicle 200 by wireless communication. The power supply section 304 supplies power to each of the strain gauge 301, the signal processing section 302, and the communication section 303.

Further, the signal processing unit 302 determines that the amount of change in the resistance value of the link member 10 detected by the strain gauge 301 (corresponding to "a value based on the amount of strain of the link member" in the present disclosure) is equal to or greater than a predetermined threshold value. In this case, the fastened state of the nut 240 is detected. Specifically, the signal processing unit 302 detects that the amount of change in the resistance value of the link member 10 detected by the strain gauge 301 remains at or above a predetermined threshold for a predetermined period of time or more (for example, one minute or more). In this case, the fastened state of the nut 240 is detected.

(Control flow of sensor device)
Next, the control flow of the sensor device 300 will be explained with reference to FIG. First, in step S11, the resistance value of the link member 10 is detected by the strain gauge 301. Next, in step S12, the signal processing unit 302 acquires information on the detected resistance value of the link member 10 from the strain gauge 301.

Next, in step S13, the signal processing unit 302 detects the fastening state of the nut 240 based on the resistance value information acquired in step S12. If it is detected that the nut 240 is loose (Yes in S13), the process proceeds to step S4. Furthermore, if it is detected that the nut 240 is not loose (No in S13), the process returns to step S11. Specifically, the difference between the resistance value detected by the strain gauge 301 this time and the resistance value detected by the strain gauge 301 previously (or the difference from the initial value of the resistance value) is outside a predetermined tolerance range. If so, it is determined that the nut 240 is loose (not secured).

As described above, in the second embodiment, the fastening state of the nut 240 is detected based on the strain of the link member 10 detected by the strain gauge 301. Thereby, the amount of strain in the link member 10 can be easily detected based on the amount of change in the resistance value of the link member 10 detected by the strain gauge 301. Furthermore, since the distortion of the link member 10 can be detected without using a magnet or the like as in the first embodiment, the number of parts can be reduced and the configuration of the sensor device 300 can be simplified. I can do it.

Note that other configurations and effects are the same as those of the first embodiment, so they will not be described repeatedly.

Note that in the first and second embodiments described above, an example was shown in which the fastening state of the nut 240 provided on the wheel 220 of the vehicle 200 is detected, but the present disclosure is not limited to this. For example, the fastening state of fastening members such as nuts attached to elevator pulleys, belt conveyor pulleys, coffee cups and merry-go-rounds installed in amusement parks, rotary play equipment installed in parks, etc. may be detected. .

Further, in the first and second embodiments described above, an example was shown in which the signal processing unit 22 (302) provided in the sensor device 100 (300) detects the loosening of the nut 240, but the present disclosure is not limited to this. . For example, the detected value of the magnetic sensor 21 (strain gauge 301) is transmitted to the ECU (Electronic Control Unit) provided in the vehicle 200 through the communication unit 23 (303), and the ECU detects the loosening of the nut 240 based on the detected value. You may.

Further, in the first and second embodiments described above, an example was shown in which the magnetic sensor 21 and the strain gauge 301 (sensor section) were attached to the link member 10, but the present disclosure is not limited to this. The sensor section does not need to be attached to the link member 10. For example, the distance between the fitting part 11 and the connecting part 12 of the link member 10 may be detected by a camera or the like provided at a position apart from the link member 10.

Further, in the first and second embodiments described above, an example was shown in which the fastening state of the nut 240 is detected based on the amount of change in the detected value of the magnetic sensor 21 (strain gauge 301), but the present disclosure is not limited to this. Not limited. The amount of strain in the link member 10 is calculated based on the detected value of the magnetic sensor 21 (strain gauge 301), and the above detection is performed based on the amount of change in the rotation angle of the nut 240 calculated based on the amount of strain. You can.

Further, in the first embodiment, an example is shown in which the magnetic sensor 21 is provided in the fitting part 11 and the magnet 30 is provided in the connecting part 12, but the present disclosure is not limited to this. The magnetic sensor 21 may be provided on the connecting portion 12 and the magnet 30 may be provided on the fitting portion 11.

Further, in the first and second embodiments described above, an example was shown in which the link member 10 of the nut 240 is attached, but the present disclosure is not limited to this. The link member 10 may be attached to a bolt (separate bolt from the wheel hub). The bolt in this case is an example of the "fastening member" of the present disclosure.

Note that in the above embodiment, the number of sensor devices 100 (300) for one wheel 220 may be changed as appropriate as long as it is one or more.

The above-described embodiments and the above-mentioned modifications may be combined as appropriate within the scope that does not cause any technical contradiction.

The embodiments disclosed this time should be considered to be illustrative in all respects and not restrictive. The scope of the present disclosure is indicated by the claims rather than the above description, and it is intended that all changes within the meaning and range equivalent to the claims are included.

10 Link member, 11 Fitting part, 11a Fitting hole, 12 Connection part, 12c Distortion part (part where distortion occurs), 21 Magnetic sensor (sensor part), 22, 302 Signal processing part (state detection part), 30 Magnet , 100, 300 sensor device (detection device), 220 wheel (fastened member), 240 nut (fastening member), 250a wheel hub (predetermined member), 301 strain gauge (sensor part), D distance.

Claims (7)

A detection device that detects distortion of a link member connecting at least two fastening members among a plurality of fastening members that fasten a predetermined member to a fastened member,
a sensor unit that detects distortion of the link member due to rotation of at least one of the at least two fastening members;
A detection device comprising: a state detection unit that detects a fastening state of the at least one fastening member based on a distortion of the link member detected by the sensor unit. The detection device according to claim 1, wherein the sensor section is attached to the link member and configured to acquire predetermined information resulting from distortion of the link member. The link member includes a plurality of fitting parts provided with a fitting hole into which any of the plurality of fastening members is fitted, and a connection part connecting the plurality of fitting parts to each other,
Further comprising a magnet provided in at least one of the plurality of fitting parts and one of the connecting part,
The sensor section includes a magnetic sensor provided to face the magnet in at least one of the plurality of fitting sections and the other of the connection section,
The state detection unit is configured to fasten the at least one fastening member based on a detection result of the magnetic sensor that changes due to a change in the distance between the magnet and the magnetic sensor due to distortion of the connection part. The detection device according to claim 2, which detects a condition. The detection device according to claim 2, wherein the sensor section includes a strain gauge provided at a portion where strain occurs in the link member due to rotation of the at least one fastening member. 1 . The state detection unit detects the fastening state of the at least one fastening member when a value based on the amount of strain of the link member detected by the sensor unit is equal to or higher than a predetermined threshold. 4. The detection device according to any one of items 4 to 4. The sensor unit detects the fastening state of the at least one fastening member when a state in which a value based on the amount of strain of the link member is equal to or higher than the predetermined threshold continues for a predetermined time or more. 5. The detection device according to 5. A detection method for detecting distortion of a link member connecting at least two fastening members among a plurality of fastening members that fasten a predetermined member to a fastened member, the method comprising:
detecting distortion of the link member due to rotation of at least one of the at least two fastening members;
A detection method comprising: detecting a fastening state of the at least one fastening member based on the detected distortion of the link member.

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