KR102304686B1 - Resistive Displacement Sensor for Monitoring Suspended Furnace Scaffolding Loads - Google Patents

Abstract

The present invention provides a resistance-type displacement sensor for measuring the displacement of a lifting system scaffold, comprising: a housing having an elongate slot formed on one side thereof in a first direction; a slide rail disposed on one side of the housing in the first direction; a slide assembled on the slide rail to allow movement in the first direction; an arm assembly assembled to the slide and having an elongated shape in a second direction perpendicular to the first direction; a sliding variable resistor disposed in the housing to correspond to the slide rail and including a variable resistance body and a sliding pin; a connecting member disposed through the slot and mechanically connecting the arm assembly and the sliding pin; a magnetic base disposed on the other side of the housing to magnetically attach the resistance-type displacement sensor to the inner wall of the furnace; and a circuit portion disposed inside the housing.

Description

Resistive Displacement Sensor for Monitoring Suspended Furnace Scaffolding Loads

The present invention relates to a resistance type displacement sensor for monitoring scaffold load in a furnace.

The content described in this section merely provides background information for the present embodiment and does not constitute the prior art.

A power plant, especially a thermal power plant, performs planned preventive overhaul every 2-3 years in consideration of the power supply and demand plan to maintain facility integrity. Improving power generation efficiency may include reducing the time required for such planned preventive maintenance. Such planned preventive maintenance stops the operation of the power plant over a period of several months and installs scaffolding inside the boiler, and workers maintain the inside.

In the case of the existing system scaffolding, the method of stacking in the bottom up based on the lower support has been used. In this case, the weight of the entire scaffolding system is concentrated on the lower part, and if even a minor problem occurs in the lower part, the risk of a serious safety accident including personal injury increases. In other words, it is important to secure the speed and safety of the scaffold installation work for maintenance of the inside of the boiler in the power plant.

Recently, in order to solve this problem, the use of a lifting system scaffold that installs a lifting machine at the top of the furnace, hangs the platform on the lifter, and hangs the scaffold system in the form of a pendant on the lower part of the platform has become popular. Compared to stacked scaffolding, which must be assembled at a gradually higher position as the scaffold is stacked up, in this way, the risk of safety accidents is low because the scaffold is installed repeatedly assembling and lifting at the lower end.

On the other hand, in order to more actively prevent safety accidents, the load applied to the scaffolding system by the workers and equipment put for work in the scaffolding system is measured at the position of the wire 122 rope to determine safety based on the eccentric load state and to warn A system has also been proposed. (See Patent Document 0001) In this case, the risk prevention system is installed on the platform, and since only the wire 122 and the rope are measured, the entire scaffold is not monitored. In the case of salvage system scaffolding, it is difficult for the entire scaffold to collapse, but there is still a risk of partial collapse due to load concentration due to positional concentration of workers or work equipment.

The maintenance environment in the furnace where the scaffolding is installed is an environment in which metal powder and dust are generated, and it is not easy to apply various measuring equipment. In addition, in order to apply the sensor to a number of locations due to the nature of the workplace, the sensor module needs to be built very economically. From this point of view, displacement measurement is more advantageous than load measurement. In addition, in the displacement measurement method, it is difficult to consider an optical or non-contact displacement sensor due to environmental constraints. A displacement sensor that is installed at multiple locations in the scaffolding system and notifies a danger when a concentration of load is detected is required, which has less environmental restrictions and is economical.

Korean Patent No. 10-1539203 (2015.07.17)

It is an object of the present invention to provide a scaffold displacement measuring device dedicated to the lifting system scaffold for measuring the displacement of the scaffold to warn in real time of a decrease in safety due to load concentration. In particular, it is an object to provide a displacement measuring device that is easy to install a sensor module, is robust to the environment, and is inexpensive.

In order to solve this problem, the resistance-type displacement sensor according to an embodiment of the present invention is a resistance-type displacement sensor for measuring the displacement of a lifting system scaffold, and a housing having a slot elongated in the first direction on one side is formed. ; a slide rail disposed on one side of the housing in the first direction; a slide assembled on the slide rail to allow movement in the first direction; an arm assembly assembled to the slide and having an elongated shape in a second direction perpendicular to the first direction; a sliding variable resistor disposed in the housing to correspond to the slide rail and including a variable resistance body and a sliding pin; a connecting member disposed through the slot and mechanically connecting the arm assembly and the sliding pin; a magnetic base disposed on the other side of the housing to magnetically attach the resistance-type displacement sensor to the inner wall of the furnace; and a circuit part disposed inside the housing. Resistance displacement sensor.

In addition, the connecting member has a 'C' shape, one side member of the 'C' shape is formed to be assembled into the arm assembly, the middle member of the 'C' shape is disposed through the slot, and the other member of the 'C' shape is at the end. The groove is formed, and the groove is assembled with the sliding pin to transmit the displacement of the arm assembly in the first direction to the sliding variable resistor.

In addition, the groove and the sliding pin is characterized in that it is formed so as to be in a loose fit state.

In addition, it is characterized in that the housing and the magnetic base are formed so as to be fixed after the relative angle adjustment.

In addition, the circuit unit includes a signal conversion unit for electrically converting the value of the sliding variable resistance; ADC (analog digital converter) for converting the analog output of the signal converter to a digital output; MCU (microcontroller unit) including a module for correcting the linearity of the sliding variable resistor and a module for determining whether to transmit a signal through communication; and a communication module.

In addition, the MCU is characterized in that, when the value of the sliding variable resistor is greater than a preset threshold value, the communication module is activated to transmit the value through communication.

In addition, it characterized in that it further comprises a tension spring for connecting between the upper end of the slide and the upper end of the housing in the first direction to compensate the load of the arm assembly.

In addition, it is characterized in that it further comprises a tension spring connecting the upper end of the housing in the first direction and the other member of the 'C' shape of the connecting member to compensate the load of the arm assembly.

In addition, the communication module further includes a Bluetooth module, and a plurality of resistance-type displacement sensors including the Bluetooth module are formed to configure a mesh network.

In addition, the MCU or the Bluetooth module is characterized in that when the value of the sliding variable resistor is greater than a preset threshold, the Bluetooth module is activated to connect the Bluetooth module to the mesh network and transmit the value through communication.

In addition, each predetermined non-hierarchical area further includes an intermediate relay server, and the intermediate relay server comprehensively manages the displacements collected from the resistance-type displacement sensor in the predetermined non-hierarchical area in consideration of the predetermined non-hierarchical structure, and a plurality of The intermediate relay server is communicationally connected to the server installed on the top platform, and the server is characterized in that it is formed to safely manage the hoisting system scaffolding as a whole.

Displacement measuring device according to the present invention can be easily installed on the lifting system scaffolding, can be used in a dusty environment, and can be economically installed at multiple locations in the furnace due to low manufacturing cost, resulting in a safety accident of the lifting system scaffolding It contributes to prevention.

1 shows a salvage system scaffolding.
2 is an assembled perspective view illustrating a resistance-type displacement sensor according to an embodiment of the present invention.
3 is an exploded perspective view illustrating a resistance-type displacement sensor according to an embodiment of the present invention.
4 is a photograph showing a resistance-type displacement sensor prepared as a sample according to an embodiment of the present invention.
5 is a photograph showing an installation example of a resistance-type displacement sensor according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

In addition, in describing the components of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the components from other components, and the essence, order, or order of the components are not limited by the terms. Throughout the specification, when a part 'includes' or 'includes' a certain component, it means that other components may be further included, rather than excluding other components, unless otherwise stated. . In addition, the '... Terms such as 'unit' and 'module' mean a unit that processes at least one function or operation, which may be implemented as hardware or software or a combination of hardware and software.

1 shows a salvage system scaffolding.

Referring to FIG. 1 , a general application form of a lifting system scaffold 10 installed for planned preventive maintenance in a power plant boiler is shown.

In general, the lifting system scaffolding 10 is a boiler 100, the cheolgolbo 110 is installed at the top, and the hydraulic lifting device 120 for drawing or winding the lifting wire 122 to the cheolgolbo 110 is disposed. . The installation of the system scaffold 140 is to assemble the platform 130 by lowering the lifting wire 122 to the lower end inside the boiler 100, and in turn raising the lifting wire 122 while raising the scaffolding 140 of multiple layers. It is assembled by assembling it layer by layer and raising it. When the scaffolding 140 of all layers is assembled, the furnace inner wall 102 and the corresponding scaffolding 140 are fixed by closely adhering to the furnace inner wall brace (not shown). When the planned preventive maintenance for the inside of the boiler 100 is completed, disassembly is performed in the reverse order of assembly while releasing the support for the inner wall of the furnace and releasing it from the lowermost scaffold 140 .

2 is an assembled perspective view illustrating a resistance-type displacement sensor according to an embodiment of the present invention.

Referring to FIG. 2 , the resistance-type displacement sensor 20 according to an embodiment may be mounted on the inner wall 102 of the furnace as a magnetic base 210 , and an arm 220 formed to be slidable includes a magnet 222 . ) is built in and can be magnetically attached to the lower end of the scaffold 140 adjacent to the furnace inner wall 102 . FIG. 2 is a view illustrating that some members are omitted as if one side is open for convenience of explanation. The finished form is formed in a structure that can be sealed inside and outside. The magnetic base 210 attached to the furnace inner wall 102 can be detached by releasing the magnetic force by turning the control dial 212, and the magnet 222 built into the arm 220 can be sufficiently separated by the operator by manpower. It may be configured to form a magnetic force to a certain degree.

3 is an exploded perspective view illustrating a resistance-type displacement sensor according to an embodiment of the present invention.

2 and 3, the resistance-type displacement sensor 20 according to an embodiment is a housing 200, a housing 200 having a slot 202 elongated in the first direction 91 on one side thereof. Slide rail 230 disposed in the first direction 91 on one side of the slide 240, assembled on the slide rail 230 to allow movement in the first direction 91, assembled to the slide 240 The arm assembly 220 having an elongated shape in the second direction 92, is disposed to correspond to the slide rail 230 inside the housing 200, and includes a variable resistance body 252 and a sliding pin 254. A connection member 260 that is disposed through the variable resistor 250 and the slot 202 and mechanically connects the arm assembly 220 and the sliding pin 254, is disposed on the other side of the housing 200 and is disposed on the inner wall of the furnace ( It includes a magnetic base 210 formed to magnetically attach the resistance-type displacement sensor 20 to the 102 , and a circuit unit (not shown) disposed inside the housing 200 .

Here, the first direction 91 is a displacement measurement direction, the second direction 92 is a direction perpendicular to the furnace inner wall 102 , and is the longitudinal direction of the arm 220 , and the third direction 93 is the direction of the arm 220 . It is defined as pointing in the width direction.

The housing 200 may include at least one sliding variable resistance assembly member 270 for fixing the sliding variable resistance 250 therein. Alternatively, the housing 200 includes a socket part (not shown) formed so that one side of the sliding variable resistor 250 is inserted into one side of the first direction 91 inside the housing 200, and the other side of the sliding variable resistor 250 is a variable resistance assembly member. (270) can be assembled.

The slot 202 formed on one side of the housing 200 may be formed with a brush structure (not shown), etc. to allow movement of the connecting member 260 but prevent the inflow of dust from the outside.

The arm assembly 220 is disposed inside the arm assembly 220 and disposed adjacent to the upper side of the first direction 91 in the second direction 92 , and includes one or more for attachment by magnetic force to the scaffold 140 . It may include a permanent magnet 222 .

The resistance-type displacement sensor 20 according to an embodiment may be attached to the furnace inner wall 102 by a magnetic base 210 . Typically, the furnace inner wall 102 has the shape of the outer circumferential surface of the pipe, and the magnetic base 210 may be easily attached to this shape. The curved shape of the attachment surface of the furnace inner wall 102 may be vertical or horizontal as well as an inclined shape, and although not shown in detail, the magnetic base 210 and the housing 200 can be rotated and fixed after rotation. can be formed with That is, the magnetic base 210 may be fixed according to the attachment surface of the furnace inner wall 102 , and the housing 200 may be rotated to be parallel to the first direction 91 and then fixed.

The slide rail 230 and the slide 240 may be a conventional one, and preferably, the peripheral portion where the slide 240 and the slide rail 230 are in close contact includes a sealing member (not shown) to prevent dust from entering. can 3, the slide 240 is a tension spring disposed to connect between the upper end of the slide 240 and the upper end of the housing 200 in the first direction 91 to compensate the load of the arm assembly 220 ( 280) may be included. Even if there is vibration by the tension spring 280 and sliding of the scaffold 140 in the second or third directions 92 and 93, the attachment state of the arm assembly 220 and the scaffold 140 is not released immediately. It has a recovery effect. In addition, since the load of the arm assembly 220 is compensated, the size of the permanent magnet 222 disposed inside the arm assembly 220 may be selected to a minimum required level. Due to this design consideration, it is possible to reduce the effect of dust that may adhere to the permanent magnet 222 .

Alternatively, although not shown, the tension spring 280 may be installed inside the housing 200 . In this case, the tension spring 280 may be disposed to connect between the inner portion of the housing 200 of the connecting member 260 and the upper end of the inner surface of the housing 200 in the first direction 91 .

The permanent magnet 222 disposed inside the arm assembly 220 provides an attachment state of the lower end of the scaffold 140 and the arm assembly 220 . The resistance-type displacement sensor 20 according to an embodiment is characterized in that it is designed to consider the environment in the field and to provide an increase in assembly convenience. It is preferable to assume that the distance between the inner wall 102 of the furnace and the scaffold 140 is not constant, and by attaching it to the scaffold 140 by a permanent magnet 222 inside the arm assembly 220, the operator can use this distance It can be easily and quickly installed without noticing the difference.

On the other hand, the lifting system scaffolding 10 is basically supported by hanging by the lifting wire 122 lowered from the top of the furnace 100. The lifting system scaffolding 10 may vibrate and shake fairly frequently due to a local eccentric load. If it is assumed that the arm assembly 220 is completely mechanically fixed to the lower end of the scaffold 140, when the arm assembly 220 is shaken in the horizontal direction (the second direction 92 or the third direction 93), the resistance type displacement sensor 20 ) of the slide rail 230 and the like may be deformed or damaged. Therefore, as in one embodiment, a structure is required to maintain a state of close contact in the first direction 91 but to allow small displacement due to vibration in the second direction 92 or the third direction 93 .

In consideration of this point, in the connection member 260 according to an embodiment, it is preferable that the groove 268 of the portion assembled with the sliding pin 254 of the sliding variable resistor 250 is formed to have a loose assembly tolerance. . Referring back to FIG. 3 , the connecting member 260 illustrates a 'C' shape. One side member 262 of the 'C' shape is formed to be assembled to the arm assembly 220, and the middle member 264 of the 'C' is formed to penetrate the slot 202 of the housing 200, and the 'C'-shaped member 262 is formed to pass through the slot 202 of the housing 200 . The other member 266 has a groove 268 formed at the end thereof, and the groove 268 is assembled with the sliding pin 254 of the sliding variable resistor 250 to only displace the arm assembly 220 in the first direction 91 . It may be formed to be transmitted to the sliding variable resistor 250 . That is, the concave groove 268 and the sliding pin 254 are formed to be assembled with a loose fit, thereby preventing the vibration of the arm assembly 220 from being directly transmitted to the sliding variable resistor 250 .

In addition, the sliding variable resistor 250 of the present invention is configured in a contact resistance type to increase reliability and to be simple mechanically and circuitly. In this case, when a force is applied to the sliding pin 254 in the second direction 92 , the contact pressure of the variable resistor may be changed to affect the resistance value. Therefore, in the in-furnace system scaffolding 10, which is a harsh environment with severe vibration, it is preferable to form a loose fit as described above.

The circuit unit includes a signal conversion unit (not shown), an analog digital converter (ADC), an MCU (microcontroller unit, not shown), a communication module (not shown) and a battery (not shown) for electrically converting the signal of the variable resistance. ) may be included. The communication module may include a wired Internet communication module (not shown), a wireless Internet communication (not shown), and a Bluetooth communication module (not shown).

The sliding variable resistor 250 according to an exemplary embodiment is a variable resistance element that is formed to have a resistance value changed in response to displacement. Accordingly, the resistance value is a case where a single parameter is changed, and it may be configured to circuitly read the resistance value in various commonly known methods. In addition, the resistance value may be converted into a digital signal after being read in an analog manner, or may be configured to be read as a digital signal from the beginning.

The MCU may be configured to control and manage the entire circuit system including the resistive sensor. Additionally, it may include an additional function, such as correcting the resistance value in consideration of the temperature at the time when the resistance-type displacement sensor 20 according to an embodiment is installed. Although not illustrated, it may be formed to control various corrections and additional functions that may be included in a typical sensor. In addition, if necessary, a routine for correcting the linearity of the resistive sensor may be included in the MCU to improve the accuracy of the resistive sensor.

On the other hand, the planned preventive maintenance in the normal furnace 100 may take 3-4 months, and the resistance-type displacement sensor 20 according to an embodiment may have a very simple circuit structure, so that substantially very little power can only be consumed. The housing 200 may include a battery at a level sufficient to supply power during the planned preventive maintenance period. In this case, in order to save the battery, the MCU may be configured to operate the communication module only when the change in the resistance value exceeds a predetermined threshold value set in advance. That is, it is possible to reduce the required battery capacity by controlling the communication to operate only when a displacement of a level that needs to be notified to the upper control layer in relation to safety occurs.

The communication module may further include only a power supply line, and may be formed to communicate through a wired Internet line.

More preferably, the resistance-type displacement sensor 20 according to an embodiment may be configured completely wirelessly, including a battery. In this case, the plurality of resistance-type displacement sensors 20 installed in the furnace 100 may be configured to use wireless Internet communication to transmit displacement values.

More preferably, the entire system can be operated by configuring a Bluetooth mesh network with low power including the Bluetooth communication module. Even in this case, the Bluetooth communication module is activated only when a safety-related situation occurs by the MCU to relay and transmit data through an adjacent Bluetooth node, thereby reducing power consumption.

In this case, it is possible to install and operate an intermediate relay server (not shown) that manages the plurality of Bluetooth nodes for each several scaffolding 140 layers. The intermediate relay server may be formed to comprehensively calculate and determine the overall behavior and deformation of the scaffold 140 in the corresponding area by synthesizing the displacements collected from each of the collected resistance-type displacement sensors 20 . In addition, in the area of the platform 130, a main server (not shown) that manages the entire lifting form system scaffold 10 may be located, and the main server and the intermediate relay server may be connected by a wired network, and the lifting form system scaffolding ( 10) When installing and building, it is possible to shorten the overall installation time by minimizing the wired wiring.

4 is a photograph showing a resistance-type displacement sensor prepared as a sample according to an embodiment of the present invention.

5 is a photograph showing an installation example of a resistance-type displacement sensor according to an embodiment of the present invention.

4 and 5, the resistance-type displacement sensor 20 and an installation example manufactured on a trial basis according to an embodiment are shown. It corresponds to a case where the curved shape of the furnace inner wall 102 is out of alignment with the horizontal of the scaffold 140 , and the magnetic base 210 and the housing 200 rotate so that the longitudinal direction of the housing 200 comes in the first direction 91 . It shows the attached state.

The above description is merely illustrative of the technical idea of this embodiment, and various modifications and variations will be possible by those skilled in the art to which this embodiment belongs without departing from the essential characteristics of the present embodiment. Accordingly, the present embodiments are intended to explain rather than limit the technical spirit of the present embodiment, and the scope of the technical spirit of the present embodiment is not limited by these embodiments. The protection scope of this embodiment should be interpreted by the following claims, and all technical ideas within the equivalent range should be interpreted as being included in the scope of the present embodiment.

Claims (11)

A resistance-type displacement sensor for measuring the displacement of a lifting system scaffold, comprising:
a housing having a slot elongated in the first direction on one side thereof;
a slide rail disposed on one side of the housing in a first direction;
a slide assembled on the slide rail to allow movement in the first direction;
an arm assembly assembled to the slide and having an elongated shape in a second direction perpendicular to the first direction;
a sliding variable resistor disposed in the housing corresponding to the slide rail and including a variable resistance body and a sliding pin;
a connection member disposed through the slot and mechanically connecting the arm assembly and the sliding pin;
a magnetic base disposed on the other side of the housing to magnetically attach the resistance-type displacement sensor to an inner wall of a furnace; and
Including a circuit portion disposed inside the housing,
The resistance type displacement sensor is formed so that the housing and the magnetic base can be fixed after a relative angle adjustment. According to claim 1,
The connecting member has a 'C' shape,
One side member of the 'C' shape is formed to be assembled to the arm assembly,
The 'C'-shaped intermediate member is disposed through the slot,
The other member of the 'C' shape has a groove formed at the end thereof, and the groove is assembled with the sliding pin to transmit the displacement of the arm assembly in the first direction to the sliding variable resistor. 3. The method of claim 2,
The resistance-type displacement sensor is formed such that the groove and the sliding pin are in a loose fit state. delete According to claim 1,
The circuit unit,
a signal converter for electrically converting the value of the sliding variable resistor;
ADC (analog digital converter) for converting the analog output of the signal converter to a digital output;
an MCU (microcontroller unit) including a module for correcting the linearity of the sliding variable resistor and a module for determining whether to transmit the signal through communication; and
A resistance type displacement sensor including a communication module. 6. The method of claim 5,
The MCU is
The resistance-type displacement sensor is configured to activate the communication module and transmit the value through communication when the value of the sliding variable resistance is greater than a preset threshold value. According to claim 1,
and a tension spring connecting the upper end of the housing and the upper end of the slide to compensate for the load of the arm assembly. According to claim 1,
The resistance type displacement sensor further comprising a tension spring connecting the upper end of the housing in the first direction and the other member of the 'C' shape of the connecting member to compensate for the load of the arm assembly. 6. The method of claim 5,
The communication module further comprises a Bluetooth module,
A plurality of the resistance-type displacement sensor including the Bluetooth module is a resistance-type displacement sensor configured to form a mesh network. 10. The method of claim 9,
The MCU or the Bluetooth module,
The resistance-type displacement sensor is configured to activate the Bluetooth module when the value of the sliding variable resistor is greater than a preset threshold, so that the Bluetooth module is connected to the mesh network and transmits the value through communication. 11. The method of claim 9 or 10,
Each predetermined non-hierarchical area further includes an intermediate relay server,
The intermediate relay server comprehensively manages the displacements collected from the resistance-type displacement sensor in the predetermined non-hierarchical area in consideration of the predetermined non-hierarchical structure,
The plurality of intermediate relay servers are connected to a server installed on the uppermost platform by communication, and the server is a resistance-type displacement sensor that is formed to safely manage the lifting system scaffolding as a whole.

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