JP7133182B2 - Looseness detection system - Google Patents

Description

The present invention relates to looseness detection systems.

As a device for detecting looseness of fasteners such as bolts and screws, Patent Document 1 discloses that a mounting bracket incorporating a pressure sensor is interposed between the member to be fastened and the bolt head, and the pressure sensor detects the looseness. A configuration for detecting tightening torque from changes in detected voltage values is disclosed.

JP 2014-228465 A

In the above-mentioned conventional detection method, not only does the mounting bracket need to be a new part to detect the loosening of the fastener, but the mounting bracket also affects the location where the fastening force acts. There was a problem that management became difficult.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a looseness detection system capable of accurately detecting the occurrence of looseness in fasteners without requiring new parts.

The object of the present invention is a fastener with a sensor for fastening an object to be fastened and detecting its own looseness after fastening, comprising a posture detection sensor including a three-axis acceleration sensor and a three-axis magnetic sensor; A looseness detection system comprising: a sensor-equipped fastener including a transmitter that wirelessly outputs detection information from a detection sensor; and a monitoring device that receives the detection information wirelessly output from the sensor-equipped fastener. The device calculates orientation information of the fastener with the sensor based on the detection information, and determines whether or not the fastener with the sensor has loosened based on changes in the orientation information over time. , a plurality of sensors are used for one fastened object, and the monitoring device compares the time-series changes in the posture information among the plurality of fasteners with sensors to detect the loosened sensor. This is accomplished by a looseness detection system that distinguishes between attached fasteners. In this looseness detection system, it is preferable that the posture detection sensor periodically outputs the detection information.

According to the present invention, it is possible to provide a looseness detection system that can accurately detect the occurrence of looseness in fasteners without requiring new parts.

1 is a schematic configuration diagram of a looseness detection system according to an embodiment of the present invention; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of a looseness detection system according to one embodiment of the present invention. As shown in FIG. 1 , the looseness detection system 1 includes a sensor-equipped fastener 10 and a monitoring device 20 .

The sensor-equipped fastener 10 includes a bolt body 13 having a head portion 11 and a shaft portion 12 , an orientation detection sensor 14 , and a signal output unit 16 . The bolt body 13 has a recess 11 a formed in the upper surface of the head portion 11 on one end side of the shaft portion 12 , and a threaded portion 12 a formed in a portion of the outer circumference of the shaft portion 12 . The sensor-equipped fastener 10 is used to fasten objects to be tied together such as various structures and equipment, and the object to be attached, the attachment position, and the like are specified by the unique fastener identification information.

The posture detection sensor 14 includes a 3-axis acceleration sensor and a 3-axis magnetic sensor, and outputs detection information for detecting the posture of the fastener 10 with sensor. The orientation detection sensor 14 is fixed to the recess 11a with a sealing resin 15. As shown in FIG. Detection information of the attitude detection sensor 14 is periodically output at regular time intervals. If this time interval is too long, it becomes difficult to grasp the occurrence of loosening of the fastener with sensor 10 in real time. is preferred, for example about 10 times a day.

The signal output unit 16 comprises a microchip 17, a battery 18, a transmitter 19 and a display 30 inside a casing. The microchip 17 receives power from the battery 18 to operate, generates output information by including fastener identification information in the detection information output from the attitude detection sensor 14 , and wirelessly outputs the output information from the transmitter 19 . The output from the transmission unit 19 is, for example, a method of directly connecting to the Internet by mobile communication such as 3G communication, or a short-range communication such as Bluetooth (registered trademark) or Zigbee to connect to the Internet via a gateway or a mobile terminal. It can be performed by a method or the like. The output from the transmission unit 19 can be performed each time the orientation detection sensor 14 generates detection information. When the microchip 17 can grasp the change of the detected information, the output information is wirelessly output from the transmitter 19 only when the detected information changes from the immediately preceding detected information, and when the detected information does not change. can reduce power consumption by wirelessly outputting the output information from the transmitting unit 19 at a cycle longer than the cycle of generating the detection information (for example, once a day). The display unit 30 can be composed of a liquid crystal panel, an LED, or the like.

The monitoring device 20 is, for example, a computer on a network, a tablet terminal, a smartphone, or the like, and includes a receiving unit 21 that receives detection information output from the fastener with a sensor 10 via a network such as the Internet, and the received detection information together with the fastener identification information, a determination unit 23 that determines whether or not the fastener 10 with the sensor is loose based on the received detection information, and a looseness occurrence indicating that the fastener 10 with the sensor is loose. and an output unit 24 for outputting the information together with the fastener identification information. The monitoring device 20 can also have a configuration in which some functions are distributed. It may be stored in a virtual server or web service provided.

Based on the detection information received from the sensor-equipped fastener 10, the determination unit 23 detects whether or not the sensor-equipped fastener 10 is loosened. That is, from the detection information of the three-axis acceleration sensor and the three-axis magnetic sensor provided in the posture detection sensor 14, the inclination angle and the azimuth angle of the fastener 10 with the sensor are calculated by a known method to calculate the posture information. exceeds the threshold, looseness occurrence information of the fastener 10 with sensor is generated.

When the object to be fastened is fixed to the installation location, the time-series change in the posture information of the fastener 10 with the sensor can be grasped as the looseness of the fastener 10 with the sensor. On the other hand, if the object to be fastened is movable, the orientation information of the fastener 10 with sensor changes as the orientation of the object changes. The looseness of the sensor-equipped fastener 10 cannot be determined. In this case, the orientation detection sensor 14 of the present embodiment is also fixed to the object to be fastened in advance, and the time-series change in the orientation information of the orientation detection sensor 14 provided in the fastener 1 with sensor and the position information fixed to the object to be fastened are calculated. Looseness of the sensor-equipped fastener 10 can be determined by comparison with time-series changes in the posture information of the posture detection sensor 14 .

A plurality of sensor-equipped fasteners 10 are normally used for one object to be fastened. The posture information of a plurality of sensor-equipped fasteners 10 used for the same object to be fastened can be obtained between them if there is no loosening of each sensor-equipped fastener 10 even if the posture of the object to be fastened changes. No relative change occurs. Therefore, by comparing time-series changes in the orientation information of the sensor-equipped fasteners 10 among a plurality of sensor-equipped fasteners 10, it is possible to determine which sensor-equipped fastener 10 has become loose. The sensor-equipped fastener 10 that has loosened can be determined, for example, based on the time-series change in posture information of the sensor-equipped fastener 10 that has been visually confirmed to have no looseness among the plurality of sensor-equipped fasteners 10. It can be carried out. Alternatively, when a large number of sensor-equipped fasteners 10 are used for one fastened object, it is possible to determine which ones have relatively different trends in time-series change in posture information among them. can.

The output unit 24 displays output information from the sensor-equipped fastener 10, loosening occurrence information generated by the determination unit 23, and the like on a monitor or the like according to predetermined conditions. Instead of displaying the loosening occurrence information on the screen (or in addition to displaying it on the screen), the output unit 24 may transmit the loosening occurrence information to another terminal or the like via e-mail or the like. Accurate information can be quickly delivered to any location, such as the actual site. By providing the sensor-equipped fastener 10 with a reception function, the corresponding sensor-equipped fastener 10 receives the loosening occurrence information output by the output unit 24 to the outside, and the loosening occurrence is displayed on the display unit 30 by characters, color, or the like. can also be displayed with

The looseness detection system 1 having the above configuration can detect the occurrence of looseness in the fastener with sensor 10 by means of the attitude detection sensor 14 incorporated therein, and the fastening force of the fastener can be detected as in the conventional art. There is no need to interpose an intervening object such as a mounting bracket at the place where the force is applied. For this reason, there is no risk of affecting the mechanical properties of the fastener, and axial force management and the like can be performed in the same manner as in the case of using ordinary fasteners. In addition, the detection information obtained by automatic detection by the posture detection sensor 14 equipped with a 3-axis acceleration sensor and a 3-axis magnetic sensor makes it possible to accurately grasp the occurrence of looseness that is difficult to detect by magnetic field measurement or visual inspection. . Furthermore, by periodically acquiring this detection information, it is possible to quickly grasp the occurrence of looseness.

The orientation detection sensor 14 provided in the fastener 10 with sensor includes other sensors such as a gyro sensor, a vibration sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, and a position sensor in addition to the triaxial acceleration sensor and the triaxial magnetic sensor. The change in the surrounding environment of the object to be fastened using the sensor-equipped fastener 10 can be quickly and accurately grasped from the detection information of various sensors, and the surrounding diagnosis can be performed. The information detected by these sensors can also be used to detect looseness in the fastener 10 with the sensor. For example, based on the rotational acceleration of the fastener 10 with the sensor detected by the gyro sensor, Data correction of the triaxial magnetic sensor may be performed.

The bolt body 13 of the sensor-equipped fastener 10 of the present embodiment is configured to include the head portion 11 and the shaft portion 12. By arranging the posture detection sensor 14 in a concave portion formed on one end side of the shaft portion, it can be used in the same manner as the fastener with sensor 10 of the present embodiment. The shaft portion 12 may be shaft-shaped without the threaded portion 12a. The sensor-equipped bolt 10 is marketed as a device in which components such as the attitude detection sensor 14 and the signal output unit 16 to be accommodated in the recessed portion 11a are integrated in advance, and the user attaches this device to a commercially available hexagon socket head bolt or the like. It can also be used by fitting it into the recess of the bolt.

The sensor-equipped fastener of the present invention is not limited to bolt-shaped fasteners. For example, when a large bolt and nut are used to fasten an object, a nut in which the posture detection sensor of the present embodiment is embedded in the side surface or the like can be used as a sensor-equipped fastener.

1 Looseness detection system 10 Fastener with sensor 11 Head 11a Recess 12 Shaft 13 Bolt main body 14 Posture detection sensor 19 Transmitter 20 Monitoring device

Claims (2)

A fastener with a sensor for fastening an object to be fastened and detecting its own looseness after fastening, comprising an attitude detection sensor including a triaxial acceleration sensor and a triaxial magnetic sensor, and detecting information of the attitude detection sensor wirelessly. a sensored fastener comprising a transmitter that outputs;
A looseness detection system comprising a monitoring device that receives the detection information wirelessly output from the fastener with the sensor,
The monitoring device calculates orientation information of the fastener with the sensor based on the detection information, and determines whether or not the fastener with the sensor is loosened from the time series change of the orientation information,
A plurality of the sensor-equipped fasteners are used for one object to be fastened,
The monitoring device is a looseness detection system that determines the looseness of the sensor-equipped fastener by comparing time-series changes in the posture information among a plurality of the sensor-equipped fasteners. 2. The looseness detection system according to claim 1, wherein said posture detection sensor periodically outputs said detection information.

Images