JP7198180B2 - Bearing misalignment detection system - Google Patents

Description

The present invention relates to a detection system for detecting misalignment in bearings between upper and lower structures of girder structures such as bridges and viaducts.

Regarding the resumption of transportation services after an earthquake, it is necessary to check whether there is any damage to structures and tracks that could hinder operation. Such confirmation work generally relies on the operator's close visual observation, and the work requires a great deal of time while moving the operator along a long route. In particular, the bearings between the upper and lower structures of girder structures such as bridges and viaducts are more efficient because confirmation work using aerial work vehicles is required. Confirmation work method is required.

For example, Patent Document 1 discloses a method in which a rod-shaped body is attached to a member constituting a bearing device so as to be movable in a direction parallel to the direction of displacement of the member, and the amount of displacement of the constituent member of the bearing device is detected from the amount of movement. ing. Instead of directly detecting the amount of displacement of the structural members of the bearing device, by making it possible to visually observe or actually measure the "rod-shaped body" that moves in conjunction, even if the structural members are inside the cover, they can be detected outside the cover. It is possible to detect the amount of displacement from

On the other hand, a method has also been proposed in which the state of the support of a girder structure can be automatically transmitted using communication means.

For example, in Patent Document 2, after arranging a rubber shoe between a base plate and an upper shoe, it is inclined to a rubber bearing provided with side blocks for improving the earthquake resistance of a girder structure such as an elevated highway bridge. A method of installing sensors to detect damage to the side blocks is disclosed. The two side blocks are mounted on opposite sides of the base plate in the width direction (perpendicular to the bridge axis) to limit changes in the position of the upper shoe relative to the base plate. The side block is bent and damaged on the side opposite to the facing surface facing the upper shoe of the rubber bearing due to the impact of the collision of the upper shoe, the sole plate, and the like. Due to such damage, the tilt angle detected by the tilt sensor changes, and the detection result is transmitted from the short-range wireless communication unit to the notification device.

Further, Patent Document 3 discloses a method of detecting deformation of a support using a simplified sensor. A plurality of thin lines of conductive paint that can detect cracks by breaking are applied to the stopper of the support so as to surround the stopper. Data on whether or not the conductive paint is energized is sent to the base station or on orbit by a transmitter, and after an earthquake, the presence or absence of breakage of the conductive paint can be detected at an early stage to detect deformation of the bearing. .

Japanese Patent Application Laid-Open No. 2003-105717 JP 2017-83407 A JP 2017-44585 A

As described above, misalignment of the bearing portion of the girder structure, which is difficult for workers to access and difficult to see, especially rubber bearings that are often used in railway structures in recent years (see Patent Document 3) It is required to detect the positional deviation of the bearing part in. It is desired that such detection can detect not only important structures such as long bridges, but also general bridges and viaducts, and a system that can handle long detection sections and many detection points is required. Such a system is required to operate immediately after a large-scale blackout due to an earthquake without the supply of commercial power. Therefore, even if a battery or the like is incorporated, it is difficult to access for replacement, and the sensor is required to be maintenance-free for a long period of time as well as operational reliability.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its object is to provide a pad-type structure inserted between upper and lower girder structures of a railroad that is displaced due to an earthquake. To provide a maintenance-free detection system for a long period of time in detecting movement of a bearing member such as a rubber bearing and transmitting a signal remotely.

A system for detecting positional displacement of bearings according to the present invention is a detection system for detecting positional displacement due to earthquakes of upper and lower structures of railroad girder structures from the movement of bearing members inserted between them and transmitting a signal by radio. a sensor switch that is fixed to the upper structure or the lower structure and energized when the support member moves a predetermined amount relative to the upper structure or the lower structure; and operation of the sensor switch. It is characterized by including a communication unit that transmits the status at predetermined intervals to a gateway connected to an external server, and a battery that operates them.

According to this invention, displacement of the upper and lower structures of a girder structure due to an earthquake can be detected without maintenance over a long period of time from the movement of the bearing members.

In the above invention, the sensor switch may have a movable portion positioned apart from the support member, and the sensor switch may be energized when the movable portion comes into contact with the support member. A plurality of the sensor switches may be arranged side by side along the side circumference of the support member. According to this invention, it is possible to detect the positional deviation of the support member with relatively little information, which contributes to maintenance-free operation over a long period of time.

In the invention described above, the bearing member may be a pad-type rubber bearing. In addition, the distance between the movable part and the pad-type rubber bearing is such that the load of a vehicle running on the girder structure cannot be supported, or the rubber bearing escape limit displacement causes damage to the pad-type rubber bearing. It may be characterized in that the quantity is obtained in advance and determined correspondingly. According to this invention, the positional deviation of the rubber bearing can be detected with relatively little information, which contributes to maintenance-free operation over a long period of time.

In the above invention, the sensor switch may be characterized in that the sensor switch is energized by the tension of a filament whose ends are respectively fixed to the upper structure or the lower structure and the support member. According to this invention, it is possible to detect the positional deviation of the support member with relatively little information, which contributes to maintenance-free operation over a long period of time.

In the above invention, a non-contact ranging sensor that measures the distance between the upper structure and the lower structure is included, the measurement is performed in synchronization with the predetermined distance, and this data is transmitted from the communication unit to the gateway. It may be characterized by transmitting to. Also, the non-contact ranging sensor may be characterized by measuring a vertical and/or horizontal reference distance between the upper structure and the lower structure. Also, the non-contact ranging sensor may be an infrared sensor or an inductive sensor. According to this invention, it is possible to more accurately detect the positional deviation of the support member.

The above-described invention may further include storage means comprising a non-volatile memory, and the communication section may store the data to be transmitted in the storage means before transmitting the data. This invention contributes to maintenance-free operation for a long period of time while more accurately detecting the positional deviation of the support member.

It is a sectional side view of the principal part of a girder-type structure. FIG. 4 is a perspective view of the bearing without the superstructure; Fig. 2 is a block diagram including a bearing misalignment detection system and an external server;

One embodiment of a bearing position deviation detection system according to a typical example of the present invention will be described below with reference to FIGS. 1 to 3. FIG.

As shown in FIG. 1, a girder structure 1 using a bearing misalignment detection system includes an upper structure 2 and a lower structure 3 supported by outriggers 4 . Here, the girder-type structure 1 is an elevated bridge for supporting a railroad track, the upper structure 2 is an adjustable girder, and the lower structure 3 is a Rahmen viaduct. A shoe seat 5 made of plate-shaped concrete mortar is fixed to the upper surface of the projecting portion 4, and a pad-type rubber bearing 6 is provided thereon as a bearing member to form a bearing and support the lower surface of the upper structure 2. doing. In the bearing displacement detection system according to the present embodiment, an example of detecting displacement due to an earthquake between the upper structure 2 and the lower structure 3 from the movement of the rubber bearing 6 will be described below. It may be a steel bearing made of steel material. Note that the horizontal direction (arrow direction) on the paper is the direction in which the track extends.

As shown in FIG. 2, the shoe seat 5 fixed to the upper surface of the projecting portion 4 is a plate-like body having a substantially rectangular main surface. Also, the rubber bearing 6 is a plate-like body having a substantially rectangular main surface that is included in the main surface of the shoe seat 5 and is arranged on the upper surface of the shoe seat 5 . That is, the rubber bearing 6 is arranged inside the shoe seat 5 when viewed from above. The direction in which the tracks extend is indicated by an arrow in the drawing.

Here, a sensor switch is arranged for detecting movement of the rubber bearing 6 by a predetermined amount. As the sensor switch, for example, a rod-type limit switch 21 having a rod 21a as a movable portion on its upper portion can be used. A plurality of rod-type limit switches 21 are arranged along the side circumference of the rubber bearing 6 , and the rod 21 a is positioned apart from the rubber bearing 6 . Here, the rod-type limit switch 21 is arranged so that the rod 21 a extends vertically upward from the side surface of the shoe seat 5 and is fixed to the shoe seat 5 . That is, when the rubber bearing 6 moves and protrudes around the shoe seat 5, the rod 21a comes into contact with the rubber bearing 6 and energizes the rod type limit switch 21, thereby detecting such movement. In other words, the movement of the rubber bearing 6 until it protrudes from the shoe seat 5 is defined as the movement of the predetermined amount.

Moreover, the wire-type limit switch 22 is also used here as a sensor switch. For example, both ends of the wire 22a, which is a filamentous body, are fixed to the rubber bearing 6 and the wire limit switch 22, respectively. Also, the main body of the wire type limit switch 22 is fixed to the projecting portion 4 . When tension is applied to the wire 22a, the wire type limit switch 22 is energized, and movement of the rubber bearing 6 beyond a predetermined amount can be detected. For example, by fixing the wire 22a near the corner of the rubber bearing 6, not only parallel movement of the rubber bearing 6 but also rotational movement can be detected. That is, the length of the wire 22a is determined according to the predetermined amount of movement to be detected.

These sensor switches are fixed to the shoe seat 5 on the side of the lower structure 3 as described above so as to detect the displacement of the rubber bearing 6 with respect to the lower structure 3 . Alternatively, the displacement of the rubber bearing 6 with respect to the upper structure 2 may be detected. For example, the rod-type limit switch 21 may be fixed so as to be suspended from the upper structure 2 to detect horizontal movement of the rubber bearing 6 with respect to the upper structure 2 . These may be combined so that movement of the rubber bearing 6 with respect to both the upper structure 2 and the lower structure 3 can be detected respectively.

In arranging these sensor switches, it is preferable to determine the separation distance from the rubber bearing 6 as follows. For example, the limit displacement that cannot support the load of a vehicle running on the girder structure 1 can be obtained in advance, and the separation distance can be determined accordingly. Also, the displacement of the rubber bearing 6 in the horizontal direction with respect to the seat 5 and the lower structure 3 or the upper structure 2, that is, the amount of escape, is the limit displacement at which the rubber bearing 6 is damaged. It is also possible to obtain a certain escape limit displacement in advance and determine the separation distance corresponding to this escape limit displacement amount.

In this embodiment, the positional deviation between the upper structure 2 and the lower structure 3 can also be measured. For example, an infrared distance measuring device 23 using an infrared sensor capable of distance measurement in three axial directions is arranged as a non-contact distance measuring sensor so as to be suspended from the lower surface of the upper structure 2 . Each of the three axes is oriented in three directions, i.e., a direction along the direction in which the track extends in the horizontal plane, a direction perpendicular thereto, and a vertical direction. fixed to This makes it possible to measure the reference distances from the reference plate 23a in a total of three directions, two horizontal directions and a vertical direction. With this reference distance, the relative displacement between the superstructure 2 and the substructure 3 can be obtained to detect the misalignment of the bearings.

As shown in FIG. 3 , these sensor switches and rangefinders are connected to a node body 11 installed on the overhang 4 , and together with the node body 11 constitute a bearing position deviation detection system 10 . The node body 11 is connected to the rod-type limit switch 21, the wire-type limit switch 22, and the infrared rangefinder, and can acquire signals regarding these operating conditions. That is, the rod type limit switch 21 and the wire type limit switch 22 can acquire an ON/OFF signal indicating whether or not the current is energized, and the infrared distance measuring device 23 can acquire a signal indicating the distance measurement result. .

Specifically, the node main body 11 includes a microcomputer 12 that acquires signals from sensors (a limit switch 21, a wire limit switch 22, an infrared rangefinder 23) and also operates as a communication unit 13, and a data I/O board 14 responsible for input and output of the node, battery 15 as a power supply for the node body 11 and sensors, storage means 16 for storing received signals as data, and necessary information for the user at the time of setting etc. and a display 17 for displaying information. The microcomputer 12 , battery 15 , storage means 16 , display 17 and sensors are all connected to the I/O board 14 . Here, it is preferable to use a non-volatile memory such as an SD memory as the storage means 16 so as to suppress consumption of the battery 15 . It is also preferable that the battery 15 is a lithium thionyl chloride primary battery that has a relatively long life.

The communication unit 13 enables wireless communication with relatively low power consumption, and is mounted on the microcomputer 12 as a module conforming to the LoRa wireless communication standard, for example. The communication unit 13 can transmit a signal to the gateway 31 , for example, enables connection to an external communication network via the base station 32 , and enables connection to an external server 33 . Furthermore, connection from the terminal 34 to the external server 33 is also possible. The terminal 34 can receive the sensing results of the sensing system 10 from a remote location. The external server 33 can use, for example, a cloud server.

Although a plurality of gateways 31 are arranged along the railroad track, one gateway 31 can receive transmissions from a plurality of bearing position deviation detection systems 10 . In other words, one gateway 31 can receive signals relating to detection of bearings at a plurality of locations. In addition, since the gateway 31 is connected to the bearing portion positional deviation detection system 10 by wireless communication, it can be installed near the ground.

Next, the operation of the bearing portion displacement detection system 10 will be described.

Referring to FIG. 3 , the system 10 for detecting positional deviation of the bearing portion acquires the operating conditions of the sensors at predetermined time intervals by means of the microcomputer 12 and transmits them to the gateway 31 . Specifically, the microcomputer 12 causes the I/O board 14 to receive signals indicating the operational status of the sensors at predetermined intervals. That is, from the rod-type limit switch 21 and the wire-type limit switch 22, an ON or OFF (energization or non-energization) signal is obtained, and from the infrared distance measuring device 23, a signal regarding the measured reference distance is obtained. The microcomputer 12 causes these signals to be transmitted from the communication unit 13 to the gateway 31 wirelessly. At this time, the microcomputer 12 causes the communication unit 13 to attach the identification codes of the individual units and sensors of the support portion positional deviation detection system 10 to the above-described signals and transmit them. These signals are also preferably stored in the storage means 16 at the same time.

Further, it is preferable to acquire/transmit the signal of the distance measurement result from the infrared rangefinder 23 in synchronization with the acquisition/transmission of the signal from the sensor switch. In other words, power consumption is suppressed by reducing the number of signal acquisitions and transmissions as much as possible. Moreover, it is also preferable to use an inductive sensor instead of an infrared sensor as a distance measuring device.

The predetermined time interval is determined within a range in which displacement of the bearing due to an earthquake or the like can be detected quickly and the bearing displacement detection system 10 can be maintenance-free for a long period of time. For example, the predetermined time interval can be 10 minutes and the maintenance-free period can be 8 years. It should be noted that the signal may be stored in the storage means 16 as described above and transmitted separately. In particular, by storing the signal in the storage means 16, in the event of an unexpected situation such as a failure of the communication network after an earthquake, etc., the signal can be sent via the gateway 31 at intervals other than the above-described predetermined time intervals. It is also possible to take out the signal at the timing.

The signal transmitted to the gateway 31 is wirelessly communicated to the base station 32, transmitted to the external server 33, and saved/accumulated. The terminal 34 can arbitrarily connect to the external server 33 to retrieve the stored signals as appropriate.

Assume that the rubber bearing 6 is displaced after an earthquake or the like and the rod type limit switch 21 or the wire type limit switch 22 is energized. Then, for example, in the case of the rod-type limit switch 21, the rod 21a comes into contact with the rubber bearing 6 and the limit switch 21 is energized. When the microcomputer 12 acquires the signal of the limit switch 21 at a predetermined time interval, this is an ON (energization) signal, and the ON signal is sent to the gateway 31 with the above identification code attached. By receiving this ON signal at the terminal 34 via the external server 33, it is possible to identify the energized sensor from the attached identification code, detect the positional deviation of the support, and detect the positional deviation. Formula structures can be identified.

As described above, according to the bearing portion positional displacement detection system 10 , the positional displacement of the bearing portion can be detected based on the positional displacement of the rubber bearing 6 . In particular, by using a sensor switch such as a rod-type limit switch 21 to reduce the amount of signals and transmitting them to the gateway 31 at predetermined time intervals, power consumption is reduced and maintenance-free for a long period of time. obtain.

In this way, since the signal related to detection of positional deviation is obtained and transmitted at predetermined intervals, it is preferable that the sensor switch does not automatically return to its original position once it reaches the energized position. In other words, when the rubber bearing 6 is displaced and the wire type limit switch 22 is turned on, even if the wire is cut or the like after that, it will not return to its original position and the current will be turned on. It is preferable to keep it. For example, for the wire type limit switch 22, a mechanism is conceivable in which a pin provided at the tip of the wire is pulled out of the sensor body, and energized based on this pin.

It is preferable that the data stored in the storage means 16 can be received even when the power supply is lost after an earthquake or when the communication network is damaged. For example, instead of the gateway 31, a communication device that can be easily transported is placed near the girder structure 1, connected to the communication unit 13 of each support position deviation detection system 10, and data stored in the storage means 16 is transmitted. can be made to

Although representative embodiments of the present invention and modifications thereof have been described above, the present invention is not necessarily limited to these, and can be modified as appropriate by those skilled in the art. That is, those skilled in the art will be able to find various alternatives and modifications without departing from the scope of the appended claims.

1 girder type structure 2 upper structure 3 lower structure 6 rubber bearing 10 bearing position deviation detection system 13 communication unit 15 battery 16 storage means 21 rod type limit switch 22 wire type limit switch 31 gateway 33 external server

Claims (9)

A detection system for detecting displacement of upper and lower parts of girder-type structures due to an earthquake from the movement of bearing members inserted between them and transmitting a signal wirelessly,
an ON/OFF sensor switch which is fixed to the upper structure or the lower structure and which is turned on or off when the support member moves a predetermined amount with respect to the upper structure or the lower structure; ,
a communication unit that transmits the ON/OFF operation status of the sensor switch to a gateway connected to an external server at predetermined intervals;
and a battery for operating them , and detecting the positional deviation on the external server side based on the transmission of the ON/OFF operation status of the sensor switch at the predetermined interval. system. 2. The displacement of the bearing portion according to claim 1, wherein said sensor switch has a movable portion positioned apart from said bearing member, and said sensor switch is energized when said movable portion comes into contact with said bearing member. detection system. 3. The system for detecting misalignment of a bearing portion according to claim 2, wherein a plurality of said sensor switches are arranged along the side circumference of said bearing member. 4. The positional deviation detection system according to claim 1, wherein said bearing member is a pad-type rubber bearing. 2. The displacement of the bearing portion according to claim 1, wherein the sensor switch is energized by a tension of a filament whose ends are respectively fixed to the upper structure or the lower structure and the bearing member. detection system. a non-contact distance measuring sensor that measures the inter- structure distance between the upper structure and the lower structure, performs measurement in synchronization with the predetermined distance, and transmits data of the inter-structure distance to the communication unit; 2. The support displacement detection system according to claim 1, wherein the signals are transmitted from to the gateway. 7. The support misalignment detection system according to claim 6 , wherein said non-contact ranging sensor measures a vertical and/or horizontal reference distance between said upper structure and said lower structure. 8. The support positional deviation detection system according to claim 6 , wherein the non - contact ranging sensor is an infrared sensor or an inductive sensor. 9. The apparatus according to any one of claims 1 to 8 , further comprising storage means comprising a non-volatile memory, wherein said communication unit stores data to be transmitted in said storage means before transmitting the data. bearing misalignment detection system.

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