JP2787121B2 - Signal adjusting device for structure diagnosis and method of using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial application field The present invention is directed to a structure or a mechanical structure, and particularly to a signal adjusting device for a structure diagnostic device for diagnosing mechanical and physical stress of a bridge and its signal adjusting device. How to use.

(B) Conventional technology Conventionally, a configuration as shown in FIG. 10 has been used to obtain stress measurement data indicating the mechanical and physical states of a structure, for example, a bridge. In FIG. 10, a strain gauge 2 suitable for the stress to be measured is attached to the measurement point of the bridge 1. The strain gauge 2 is connected to one end of a cable 3 and its detection output is input to a signal conditioner 4 connected to the other end of the cable. In order to adjust the detection signal from the strain gauge 2 to a signal of a specific item that can be input to the measuring instrument, the signal adjuster 4 performs a bridge connection in which a specific combination of the strain gauge and the resistance is respectively corresponding to the stress to be measured. To use. A power supply voltage is supplied to the input terminal of the signal conditioner 4 from the input terminal via the input connector 5 of the measuring instrument and the cable 3 connected to the input terminal of the bridge connection. The adjustment output is taken out and the measuring instrument 6
The output is recorded or processed as measurement data of the measured item of the bridge.

(C) Problems to be solved by the present invention Since the items of the measured stress of the bridge are various such as bending stress, shear stress, uniaxial stress and in-plane stress, the signal conditioner 4 conventionally corresponds to the items. A bridge that has general versatility to form is used. Then, a professional measurement technician performs connection between the strain gauge 2 and one end of the cable 3 and connection between the signal adjuster 4 and the other end of the cable in accordance with the item to be measured specified at the measurement site. A bridge for performing adjustment suitable for the item to be measured is assembled by soldering or the like in the signal adjuster 4 arranged on the measuring instrument side. This bridge configuration work involves connecting a cable core to a specific terminal or short-circuiting between terminals, corresponding to a specific measurement item at the connection terminal of a general-purpose signal conditioner, so that one side of the bridge circuit is In addition, complicated work for wiring such that the strain gauge is incorporated is required. For this reason, a technician specializing in measurement is required, and even if an inexperienced technician attempts to perform the wiring work of the bridge, the work is complicated, so that there are problems such as erroneous wiring and a large process load.

In addition, as shown in FIG.
The cable 3 is connected between the strain gauge and the signal conditioner 4 on the side thereof, so that it is necessary to connect the strain gauge at one end of the cable 3 and the signal conditioner at the other end. The work was also complicated.

An object of the present invention is to provide a signal diagnostic device for structure diagnosis in which a dedicated bridge applied to a specific item of stress to be measured is formed and incorporated.

Another object of the present invention is to provide a method for suitably using the above-mentioned signal adjusting device for structure diagnosis for structure diagnosis.

(D) Means for Solving the Problems The signal conditioning device of the present invention includes a dedicated bridge circuit in which a bridge is formed exclusively for detecting a specific item of a measured stress of a structure, Gauge connecting means for connecting a strain gauge to a dedicated bridge circuit, a connector having one end connected to a measuring instrument, an input voltage from the measuring instrument to the bridge circuit, and an adjustment signal from the bridge circuit. Are connected to the dedicated bridge circuit, and a casing to which the dedicated bridge circuit and the gauge connecting means are attached.

Further, the method of using the structure diagnostic signal adjusting device according to the present invention includes the step of arranging the dedicated structure diagnostic signal adjusting device on a strain gauge side attached to a measurement point of the structure and reading the lead from the strain gauge. A wire is connected to the gauge connection means, and a connector of the cable is connected to a measuring instrument.

(E) Function In the structural diagnostic adjustment device of the present invention, a dedicated bridge circuit is formed for each specific item of the stress to be measured, so that the measurer can prepare a dedicated adjustment device according to the measurement item. Good connection with a strain gauge can be easily performed.

Further, according to the method of use of the present invention, since the gauge connecting means of the adjusting device is directly connected to the strain gauge on the strain gauge side, the connecting operation is simplified.

(F) Embodiment FIG. 1 shows an embodiment of a method of using the signal conditioning apparatus of the present invention. In FIG. 1, it is surrounded by a broken line.
11 is a signal adjusting device according to the present invention. This signal conditioning device 11 generally contains a specified item of the stress to be measured, for example, a bridge circuit wired exclusively for measuring the shear stress,
A connection terminal 12 as a gauge connection means for incorporating the strain gauge 2 as one element of the bridge circuit.
And a cable 3 that houses signal lines for supplying an input voltage to the bridge circuit and extracting a diagnostic adjustment output from the bridge circuit. One end of the cable 3 is fixedly connected to a predetermined terminal of the bridge circuit, and the other end is a measuring instrument.
The connector 5 to be connected to 14 is attached. The cable 3 can be used with a length of several tens of meters, and can largely separate the strain gauge 2 side from the measuring instrument 14 side. For this reason, after the strain gauge 2 is fixed to a measurement point such as a bridge, its lead end is connected to the connection terminal 12 of the casing 13 installed near the strain gauge in a one-touch manner by being sandwiched.

FIGS. 2A and 2B are a front view and a top view of the signal conditioner 11, respectively. Four connection terminals 12 are attached to the upper surface of the casing 13, each of which has a red,
Colored by white, black and green. A terminal 15 for grounding is attached to the side surface of the casing 13. Further, a magnetic rubber plate 16 is provided on the bottom surface of the casing 13 to facilitate attachment to a bridge.

FIG. 3 shows a bridge circuit formed exclusively for measuring a shear stress as a measurement item of a stress to be measured. In FIG. 3, the portion surrounded by a broken line is the casing.
The bridge circuit configuration 17 formed for shear stress accommodated in 13 is shown, and white circles in the figure indicate connection terminals. Conventional general-purpose signal conditioners have been configured to have a large number of bridges in order to provide versatility.However, in a dedicated signal conditioner according to the present invention, an adjusting resistor is connected between specific terminals, Alternatively, the bridge circuit is short-circuited and a bridge circuit corresponding to each item is already formed as shown in the figure. The bridge circuit itself corresponding to each measured stress has a known configuration. Bridge circuit configuration 17
Red, white, black and green conductors from the connection terminal
It is connected to 12 color-coded terminals of the same color. Further, the bridged red and black conductors are connected to the input voltage supply signal lines A and C in the cable 3, and the white and green conductors are connected to the diagnostic adjustment output signal lines B and D from the bridge. It is connected. The signal line E of the cable 3 is a ground line, and is connected to a ground terminal 15 of the casing 13.

FIG. 4 shows an equivalent circuit diagram of the bridge circuit configuration 17 of FIG. As shown in FIG. 4, the strain gauge 2 is provided between the red and green conductors and between the green and black conductors, that is, between the red and white connection terminals 12 and the green and black connection terminals in correspondence with FIG. Connected between 12 In this case, since the measurer is instructed to use the connection terminal for the shear stress measurement, the color-coded connection terminal can be connected to the strain gauge more easily and without error.

The signal conditioning device configured as described above is dedicated to shear stress measurement. That is, when measuring the shear stress of the bridge, the measurer selects the dedicated signal conditioner and carries it to the measurement location. Two strain gauges 2 are fixed to the measurement points of the bridge, and the leads are connected between the red and green and green and black connection terminals 12 of the signal conditioner 11 as indicated. Next, the cable 3 of the signal conditioning device 11 is extended to a position where the measurement is not hindered, and the connector 5 is connected to the measuring device 14 already arranged at the position and electrically connected to the measuring device 14. . This measuring device 14 is a device for automatically processing the structure diagnostic data proposed by the present applicant as Japanese Patent Application No. 1-326770, and is not directly related to the present invention. A dedicated bridge circuit connection 17 from the measuring instrument 14 via the signal lines A and C of the cable 3
A predetermined input voltage is supplied to the red and black conductors, and a diagnostic adjustment output proportional to the strain of the strain gauge is output via the green and white conductors and the signal lines D and B of the cable 3.
It is led to. The measuring device 14 is provided with an amplifier, and the diagnostic adjustment output is amplified and thereafter processed as shear stress diagnostic data.

FIG. 5 shows a bridge circuit configuration 18 when an in-plane stress is specified as the stress to be measured. In the in-plane stress measurement, a dedicated signal conditioner which forms a bridge circuit shown in FIG. 5 and is housed in a casing is used. FIG. 6 shows the fifth
FIG. 4 is an equivalent circuit diagram of the figure, in which two strain gauges are connected in series between red and green connection terminals 12. The handling and measuring method of this signal conditioning device is the same as in the case of shear stress measurement.

FIG. 7 shows a bridge circuit configuration 19 dedicated to uniaxial stress measurement, and FIG. 8 shows a bridge circuit configuration 20 wired exclusively for bending stress measurement. In these stress measurements as well, the measurer can easily connect the strain gauge to the designated location of the connection terminal colored in the same manner as described above.

FIG. 9 shows a top view of a signal conditioning device used for simultaneously measuring the stress on both surfaces. For example, when measuring the shear stress on both surfaces, a casing 21 having eight connection terminals shown in FIG. 9 is used, and two bridge circuit configurations 17 shown in FIG. 3 are connected in parallel in the casing. In this way, the average value of the shear stress on both sides can be taken out as a diagnostic adjustment output.

(G) Effect The signal diagnostic device for structure diagnosis according to the present invention is configured as an off-the-shelf product with a dedicated bridge circuit configuration corresponding to each item of the measured stress of the structure. The need for complicated and specialized work of assembling a bridge circuit at the time of measurement by a specialized technician for each item of stress to be measured using the adjusting device is eliminated, and anyone can operate the signal adjusting device easily and without fail. be able to. Furthermore, it is possible to standardize and reduce the size of the dedicated signal adjusting device, and it is possible to dramatically promote automation of structure diagnosis and labor saving.

Further, since the method of using the signal adjusting device for structure diagnosis of the present invention uses the signal adjusting device arranged on the strain gauge side, the strain gauge can be easily attached directly to the gauge connecting means of the signal adjusting device. This eliminates the complexity of connecting a strain gauge to a cable as in the prior art. Also, the length of the cable from the signal conditioner to the measuring instrument can be increased, and standardization and standardization can be performed as a dedicated signal conditioner including a cable with a connector.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a diagnostic system using a signal adjusting device for diagnosing a structure according to the present invention, FIGS. 2A and 2B are front and top views of the signal adjusting device of the present invention, and FIG. FIG. 4 is a diagram showing a bridge circuit configuration dedicated to shear stress measurement, FIG. 4 is an equivalent circuit diagram of FIG. 3 with a strain gauge connected thereto, FIG. 5 is a diagram showing a bridge circuit configuration exclusively for in-plane stress measurement, FIG. 5 is an equivalent circuit diagram of FIG. 5 to which a strain gauge is connected, FIG. 7 is a diagram showing a bridge circuit configuration dedicated to uniaxial stress measurement, FIG. 8 is a diagram showing a bridge circuit connection dedicated to bending stress measurement, and FIG.
The figure is a top view of the casing of the signal conditioner used for the double-sided stress measurement, and FIG. 10 is a schematic diagram of a diagnostic system using the conventional signal conditioner. 1 ... symbol, 2 ... strain gauge, 3 ... cable, 5 ...
... Connector, 11 ... Signal adjustment device, 12 ... Gauge connection terminal, 13,21 ... Case, 14 ... Measuring instrument, 1
7, 18, 19, 20 …… Bridge circuit connection.

Claims (2)

(57) [Claims] 1. A strain gauge connected between a strain gauge for detecting diagnostic data indicating stress of a structure such as a bridge and a measuring device for processing the diagnostic data, and receiving a detection signal from the strain data to input the diagnostic data. A structure diagnostic signal adjustment device that adjusts to a signal suitable for the measured stress of the object and outputs the signal to the measuring device, in order to detect a specific item of the measured stress of the structure,
A dedicated bridge circuit formed exclusively for detecting the item, a gauge connection means for connecting the strain gauge to the dedicated bridge circuit, and a connector having one end connected to the measuring instrument; A cable in which each signal line for supplying an input voltage from the measuring device and outputting an adjustment signal from the bridge circuit to the measuring device is connected to the dedicated bridge circuit; and the dedicated bridge circuit and gauge connection means. And a casing for mounting the device. 2. A dedicated bridge circuit formed exclusively for detecting a specific item of a stress to be measured of a structure, and a gauge connection means for connecting a strain gauge to the dedicated bridge circuit. A connector having one end connected to a measuring instrument, each signal line for supplying an input voltage from the measuring instrument to the bridge circuit and outputting an adjustment signal from the bridge circuit to the measuring instrument, A method for using a signal adjusting device for a structure diagnosis, comprising a cable connected to a dedicated bridge circuit, a casing for mounting the dedicated bridge circuit, and a gauge connecting means, wherein a specific item of a measured stress of the structure is The dedicated structure diagnostic signal adjustment device is arranged on a strain gauge side attached to a measurement point of a structure, and a lead wire from the strain gauge is connected to the gauge. Means for connecting to the means, and the connector of the cable is connected to a measuring instrument.