KR100424924B1 - A rod extensometer strenthened waterproof function - Google Patents

Abstract

The present invention relates to a length strain measuring device embedded in the ground such as a dam or tunnel to measure the length strain of the surrounding crust, more specifically,

A rod for compressing the spring by reducing the length of the protruding outwardly, which is pressed inwardly of the measuring device according to the pressure applied to the perception by deforming the relative position of the surrounding perception by the change of the external environment;

A spring for converting the linear displacement amount of the rod into a force of pressure;

A force transmission unit for transmitting a force of pressure by the spring to a pressure sensor;

A diaphragm in contact with one end of the spring to directly receive the pressure of the spring, a vibrating string whose tension is changed by the received pressure, a vibrating string fixing part for fixing one end of the vibrating string, and a ground displacement amount through the resonance frequency of the vibrating string. A transformer for converting into an electrical signal and a vacuum housing formed therein and an outer ring having an O-ring formed on the outer circumference thereof, wherein the diaphragm, the vacuum housing, the transformer, and the vibration fixing unit are vacuum welded sequentially to form a closed structure. A pressure sensor characterized by forming;

A protection tube that includes the rod, the spring, the force transmission unit, and a pressure sensor and protects the measuring device from an external impact; And

The invention relates to a length deformation measuring device for measuring the ground displacement of a civil engineering structure, such as a dam or tunnel, including a rod guide coupled to one end of the protective tube to guide the rod to move in a straight direction.

In the length deformation measuring apparatus of the present invention, the sensor is prevented from being damaged due to the penetration of moisture, in particular by enhancing the waterproof function, so that it can be used for a long time with accurate measurement.

Description

Longitudinal deformation measuring device with enhanced water resistance {A ROD EXTENSOMETER STRENTHENED WATERPROOF FUNCTION}

The present invention relates to a length strain measuring device for measuring the length strain of the surrounding crust by embedding in the ground such as a dam or tunnel. In particular, the present invention is characterized by having a complete waterproof structure while applying the existing pressure sensor to the strain measuring device.

The conventional length strain measuring device, which measures the length strain of the surrounding crust by embedding it in the ground such as a dam or a tunnel, is not completely waterproof and causes many problems. That is, as time passes, moisture penetrates inside the measuring device. In the case of a conventional vibration string measuring device having a structure in which a string is directly connected to a spring, the string itself is rusted and its tensile strength is changed. . In addition, even though it could not be used for a long time due to corrosion, it was virtually impossible to replace it with a new measuring device because it was buried in the ground such as a dam or tunnel even if it was once corroded and lost its function as a measuring device.

In addition, in the conventional vibration string length measurement apparatus, the connection between the string and the spring has a disadvantage that the measurement frequency value is changed due to the vibration and is sensitive to the change in temperature.

In order to solve the problems of the prior art as described above, an object of the present invention is to adopt a conventional pressure sensor as one component of a length deformation sensor, and to provide a length deformation measuring device having a structure in which a waterproof function is enhanced.

1 is a longitudinal cross-sectional view of a longitudinal deformation measuring apparatus using a vibration expression pressure sensor according to the present invention.

2 is an external configuration diagram of a length deformation measuring apparatus using a vibration expression pressure sensor according to the present invention.

The operation principle of the length deformation measuring apparatus of the present invention created to achieve the above object will be described with reference to FIG. 1. That is, in the case where the longitudinal deformation measuring device 100 having the pressure sensor 140 in the waterproof protective tube is embedded in the ground such as a dam or tunnel in order to measure the ground displacement of a civil structure such as a dam or tunnel, the dam or tunnel When a displacement occurs in the back structure, the displacement is measured by the following procedure.

First, the rod 110 protruding outwardly from one end of the length-deformation measuring device 100 according to the pressure applied to the earth's perception by the deformation of the relative position of the surrounding perception due to a change in the external environment is directed toward the inside of the measuring device. Compressing the spring 120 in the interior of the length deformation measuring apparatus 100 by reducing the length of the protruded outwardly, and converting the linear displacement of the rod 110 by the force of pressure through the spring 120. Transmitting a pressure to the pressure sensor 140 after the conversion, sensing the magnitude of the received pressure, and then converting the pressure to a size of a measurable unit suitable for the characteristics of the pressure sensor; Convert the size into the size of the length unit for easy reading by the user to the external monitor (not shown) through a cable 190 connected to the other end of the length deformation measuring apparatus 100 Through a step of length is made as strain measurement.

Here, in order to prevent the penetration of moisture existing in the ground, the protective tube 200 of the molding structure is manufactured so that all of the rod 110 and all the portions except the cable 190 are included therein. O-rings (221) (222) (223) inside the case including both ends of the protective tube (200) connected to the cable (190) or rod (110) to prevent the penetration of the secondary On the other hand, the pressure sensor may be a vibration-type pressure sensor or an electric resistance pressure sensor, each measuring principle is as follows.

That is, when the pressure sensor is a vibration-type pressure sensor composed of a vacuum portion, a coil, a permanent magnet portion, and a lateral height portion of the rear end of the diaphragm portion and the string in which the pressure sensor is vacuum welded to each other to form a system. When the restoring force is transmitted to the diaphragm located at one end of the pressure sensor of the pressure sensor, the string vibrates due to the change of tensile force of the string tightly connected to the diaphragm, and the change of vibration frequency is caused by the change of AC voltage by the induced magnetic field. Convert to measure the length strain.

On the other hand, when the pressure sensor is an electrical resistance type pressure sensor made of a thin plate, the plate is bent when the restoring force of the compressed spring is transmitted to the plate of the pressure sensor, and the change in electrical resistance is converted into a voltage to measure the length deformation. .

Meanwhile, referring to FIG. 1, the basic configuration of the length deformation measuring apparatus according to the present invention is as follows. In other words, the length deformation measuring apparatus according to the present invention is deformed due to a change in the external environment. As a result, the rod 110 compresses the spring by being pressed inwardly of the measuring device according to the pressure applied to the crust and reduces the length of the projecting to the outside, and the spring converting the linear displacement of the rod 110 into a force of pressure. 120 and, a force transmission unit 130 for transmitting the force of the pressure by the spring 120 to the pressure sensor, and a diaphragm directly receiving the pressure of the spring in contact with one end of the spring 120, the received The ground displacement is changed into an electrical signal through a vibrating string whose tension is changed by pressure, a vibrating string fixing part for fixing one end of the vibrating string, and a resonant frequency of the vibrating string. The transformer has a vacuum space therein and a vacuum housing having an O-ring formed on the outer circumference thereof, wherein the diaphragm, the vacuum housing, the transformer and the vibration fixing unit are vacuum welded sequentially to form a sealed structure. A pressure sensor 140, the rod 110, the spring 120, the force transmission unit 130 and the pressure sensor 140, the protection tube 200 to protect the measuring device from an external impact, and the Coupled to one end of the protective tube 200 is characterized in that it comprises a rod guide 210 for guiding the rod 110 to move in a straight direction.

Here, the pressure sensor 140, the front end diaphragm, vacuum housing, transformer (coil and permanent magnet) and the rear end of the end to protect the vibrating string from the external shock and to prevent the deformation of the string from the external temperature change and moisture It has a vacuum welded structure sequentially. The operation principle is that when the restoring force of the compressed spring 120 is transmitted to the diaphragm located at one end of the pressure sensor, the string vibrates due to the change in the tensile force of the vibrating string that is tightly connected to the diaphragm, and the vibration frequency change at this time Is a method of measuring the length deformation by converting the signal into a change in AC voltage caused by an induction magnetic field. However, the ground displacement measuring apparatus according to the present invention has a resilience force of a conventional electric resistance pressure sensor, that is, a compressed spring, in addition to a vibration pressure sensor. It is also possible to use an electric resistance type pressure sensor for measuring the length strain by converting the electrical resistance change at this time to the voltage value when the plate is transmitted to the thin plate of the pressure sensor. 100 is in contact with the pressure sensor 140 to further enhance the waterproof function, the passage of the signal line inside the measuring device 100 and the outer periphery A signal line waterproof pin 151 having an O-ring 222, a signal line waterproof plug 150 having an cavity for inserting the signal line waterproof pin, and having an O-ring 221 formed at an outer circumference thereof, and the signal line waterproofing Contact with the stopper 150 and the waterproof coating 160 filling the inside of the measuring device 100 to a predetermined thickness, in contact with the waterproof coating 160, combined with one end of the measuring device 100, the waterproof around the It may further include a housing 170 having an O-ring formed therein, and a cable gland 180 which is partially inserted into the housing 170 to fix and protect the cable 190 from external shocks. With reference to the drawings will be described in detail the configuration and measuring method of the length deformation measuring apparatus according to the present invention.

1 is a cross-sectional configuration of the vibration strain pressure sensor is applied as an embodiment of the length deformation measuring apparatus according to the present invention.

FIG. 2 is an external configuration diagram of a length strain measuring device in the case of FIG. 1. FIG.

First, referring to FIG. 1, a length variable shaft (displacement rod and displacement on the drawing) is connected to one end of the length deformation measuring device by applying a pressure applied to the perception by changing the relative position of the perceptual perception due to a change in the external environment. The spring is compressed when it is transferred to the spring through the transmission section.

At this time, when the compressed spring is restored to its original position and the restoring force of the spring is transmitted to the diaphragm located at one end of the pressure sensor, the string vibrates due to the change in the tension force of the string that is tightly connected to the diaphragm. Measure by converting to AC voltage change by magnetic field. Converting to the change of the AC voltage belongs to the step of converting to the size of the unit that can be measured to match the characteristics of the vibration expression pressure sensor. The size of the measurement unit converted by the change of the AC voltage is converted into the size of a unit that is easy for a user to read (for example, the length of a bar chart) and transmitted to an external monitor through a cable.

On the other hand, if the pressure sensor is an electrical resistance type pressure sensor made of a thin plate, the plate is bent as the restoring force of the compressed spring is transmitted to the plate of the pressure sensor, and the electrical resistance change at this time is converted into voltage and measured.

The length deformation measuring apparatus according to the present invention through FIG. 2 will be described in more detail for each component as follows.

The cable gland 180 fixes and protects the signal cable (output line) and serves as a primary waterproofing.

The housing 170 is a tooth connecting the cable gland and is connected to the vibration expression displacement gauge protective tube 200. The housing is male and female threaded and has an O-ring for primary waterproofing.

The protective tube 200 functions as a fixing part of a component to be installed therein, and is designed to be easily assembled by varying the inner diameter of the protective tube for each position where the component is to be installed.

The spring 120 functions to convert the thread displacement of the rod into a force and is designed to maintain elasticity.

The rod 110 transmits the yarn displacement in a straight line to the spring.

Cable waterproof plug 150 is provided with a signal line waterproof pin 151 to act as a waterproof while passing the signal line. Here, the outer periphery of the cable waterproofing plug 150 and the signal line waterproofing pin 151 is respectively formed an O-ring for waterproofing.

The pressure sensor 140 normally maintains the string in a tensioned state in a vacuum space, and the tensile strength of the string varies according to the deformation of the diaphragm having a thickness of about 0.2t.

The force transmission unit 130 functions to transfer the force of the spring to the diaphragm.

The rod guide 210 allows the rod to move in a straight line. The rod guide has a male thread on the inner circumference and has an o-ring to act as the primary waterproof.

The length deformation measuring device according to the present invention has an advantage that it can be used for a long time with accurate measurement because it prevents the sensor from being damaged due to moisture penetration by enhancing the waterproof function.

In addition, by adopting the pressure sensor as a component of the length deformation measuring device, it is possible to reduce the measurement error caused by the temperature change, thereby improving the reliability, stability, and reproducibility of the sensor.

Claims (9)

delete delete delete In the device for measuring the ground displacement of civil engineering structures, such as dams or tunnels, A rod compressing the spring by reducing the length of the protruding outwardly, which is pressed inwardly of the measuring apparatus according to the pressure applied to the perception by changing the relative position of the perception of the surroundings by the change of the external environment; A spring for converting the linear displacement amount of the rod into a force of pressure; A force transmission unit for transmitting a force of pressure by the spring to a pressure sensor; A diaphragm in contact with one end of the spring to directly receive the pressure of the spring, a vibrating string whose tension is changed by the received pressure, a vibrating string fixing part for fixing one end of the vibrating string, and a ground displacement amount through the resonance frequency of the vibrating string. A transformer for converting into an electrical signal and a vacuum housing formed therein and an outer ring having an O-ring formed on the outer circumference thereof, wherein the diaphragm, the vacuum housing, the transformer, and the vibration fixing unit are vacuum welded sequentially to form a closed structure. A pressure sensor characterized by forming; A protection tube that includes the rod, the spring, the force transmission unit, and a pressure sensor and protects the measuring device from an external impact; And And a rod guide coupled to one end of the protective tube to guide the rod to move in a straight direction. delete delete 5. The signal line waterproof pin according to claim 4, wherein the pressure line is in contact with the pressure sensor, and has a cavity for inserting the signal line waterproof pin. And a signal line waterproof stopper having a ring formed therein. 8. The waterproof coating according to claim 7, wherein the waterproof coating is filled with a predetermined thickness in contact with the signal line waterproof stopper, and the waterproof coating is in contact with one end of the measuring apparatus and has an O-ring for waterproofing therein. Length measuring device further comprises a housing. 9. The apparatus as claimed in claim 8, further comprising a cable gland inserted into the housing to fix the cable and to protect the cable from external shock.