KR20220062777A - Spring hanger with displacement measurement function - Google Patents

Abstract

The present invention relates to a spring hanger having a displacement measuring function. According to an embodiment of the present invention, disclosed is a spring hanger configured to be fixedly installed in a facility to support a pipe and to absorb vibration or shock caused by a load change or thermal expansion/contraction of the pipe through the tension/compression of a spring installed inside the pipe. The spring hanger is configured to measure pipe displacement through a simple sensor structure while measuring pipe displacement in order to determine abnormal signs of the pipe.

Description

Spring hanger with displacement measurement function

The present invention relates to a spring hanger having a displacement measurement function, which is fixedly installed in a facility to support the pipe, and buffers vibrations or shocks caused by changes in the load of the pipe or thermal expansion/contraction through the tension/compression of the spring installed therein. As a spring hanger configured to do so, it relates to a spring hanger having a displacement measuring function configured to measure a pipe displacement to determine an abnormal symptom of a pipe, but to measure the pipe displacement through a simple sensor structure.

Spring hangers are used to support loads by fixing pipes in facilities such as petrochemical plants and power plants.

In the piping of industrial facilities such as petrochemical plants and power plants, vibrations or shocks may occur due to the change in the load of the piping depending on whether the fluid flows or the thermal expansion/contraction of the piping according to the change in the temperature of the fluid. It provides the function of buffering shock and displacement through the tension/compression of the spring.

However, since the spring hanger may cause abnormal symptoms according to the change in the characteristics of the spring and/or the change in operating conditions due to long-term use, it is necessary to determine the characteristic change and/or abnormality of the spring hanger to manage the safety of the facility. techniques have been proposed.

As an example of this prior art, Republic of Korea Patent Registration No. 10-1227772 (Jan. 23, 2013) discloses a spring hanger soundness test by making it possible to easily and accurately determine the characteristic change of a coil spring according to its durability even without disassembling the spring hanger. A configuration for diagnosing abnormal symptoms in advance was proposed.

As another example of the prior art, Republic of Korea Patent Registration No. 10-1690972 (2016.12.23.) measures the reciprocation value of the spring installed inside the spring hanger as a change in pressure to determine whether the spring is working properly even with the naked eye or from a distance. A spring action detection device in the spring hanger that can be detected is proposed.

As another example of the prior art, Republic of Korea Patent Registration No. 10-1761718 (2017.07.20.) discloses that the installation location of the spring hanger is installed in a high-altitude area where it is difficult for an inspector to access, or is installed in a too far or dark area. When it is difficult to check the instructions provided on the hanger, a configuration was proposed to enable the monitoring of the instructions through the digital instruction monitoring device, so that the support load of the spring-based hanger and the amount of pipe displacement can be easily recognized.

However, in the prior art, the deformation amount of the coil spring is analyzed using the displacement information and load information input through the displacement measuring magnetic sensor and the load cell, or the reciprocating motion value of the spring installed inside the spring hanger is measured as a change in pressure. The configuration for measuring the displacement is complicated because it determines whether the spring operates normally or connects the pointer protruding on the outside of the spring hanger with the displacement sensor through the rod-type guide fixing part to determine the displacement of the spring. There was a limit to that.

Republic of Korea Patent Registration 10-1227772 (2013.01.23.) Republic of Korea Patent Registration 10-1690972 (2016.12.23.) Republic of Korea Patent Registration 10-1761718 (2017.07.20.)

The present invention has been devised in consideration of the problems of the prior art as described above. It is fixedly installed in a facility to support the pipe, and the tension/compression of the spring installed therein is applied to the vibration or shock generated by the change in the load of the pipe or the thermal expansion/contraction. An object of the present invention is to provide a spring hanger configured to buffer through a spring hanger having a displacement measuring function configured to measure the pipe displacement to determine an abnormal symptom of the pipe but measure the pipe displacement through a simple sensor structure.

According to one aspect of the present invention for achieving the above object, the body including a cylindrical inner space disposed in the transverse direction; a coil-type spring disposed to be compressed or restored in the cylindrical inner space along the cylindrical axial direction; a movable rod having one end coupled to a locking plate disposed outside one end of the coil-type spring, and the other end protruding outward through a through hole formed in one side of the body; a movable link member rotatably coupled to a support member installed on one side of the body through a first hinge shaft, and rotatably coupled to the other end of the movable rod through a second hinge shaft; a support link member having one end coupled to one side of the movable link member in a rotatable state through a third hinge shaft, and a pipe-side element coupled to the other end; a rotation angle measuring sensor installed on the support member and receiving a rotational state of the first hinge shaft using a mechanism element to measure the rotational displacement of the first hinge shaft; and a calculation unit configured to receive a measurement result of the rotational displacement of the first hinge shaft from the rotation angle measurement sensor and calculate the vertical displacement of the support link member.

Preferably, the mechanism element includes a first gear installed coaxially with the first hinge shaft, and a rotational state of the first hinge shaft from the first gear, and the first hinge shaft using an input shaft installed coaxially. and a second gear that transmits the rotation state to the rotation angle measurement sensor.

Preferably, the rotation angle measuring sensor is a magnetic rotary encoder installed inside a waterproof casing, and the rotational state of the first hinge shaft is transmitted based on a change in rotation angle of a magnet installed at the input end of the input shaft.

Preferably, in a state in which the other end of the support link member receives an external force in an upward direction or a downward direction by the pipe-side element, the second hinge shaft and the third hinge shaft are respectively moved in a first rotational direction or a second rotational direction. It revolves around the first hinge axis.

Preferably, in a state in which the second hinge shaft and the third hinge shaft revolve about the first hinge shaft in a first rotational direction or a second rotational direction, respectively, the other end of the movable rod is a second hinge shaft together with the second hinge shaft. It revolves in one rotational direction or a second rotational direction, and one end of the movable rod compresses or restores the coil-type spring through the locking plate.

Preferably, a support plate is provided on the inner side of one side of the body to support the outer side of the other end of the coil-type spring, which is disposed at a position opposite to the locking plate, and one side of the support plate extends toward the inner space of the spring coil. The extended piece is integrally formed and extends toward the inner space of the spring coil so as to be disposed corresponding to the extended piece, one end is fixedly coupled to the extension piece, and the other end is fixedly coupled to the inner side of one side of the body. A member is provided, and a strain gauge for measuring the deformation occurring in the fixed coupling member according to a state in which the coil-type spring is compressed or restored is installed in the fixed coupling member.

Preferably, the calculation unit receives the measurement result of the deformation occurring in the fixed coupling member from the strain gauge and calculates the load transmitted from the pipe-side element, and the calculated load is less than or equal to a preset second reference value. When the vertical displacement of the support link member exceeds a preset first reference value, an alarm signal determined as an abnormal symptom of the pipe is generated.

Preferably, the present invention is configured to further include a solar power module installed on the upper portion of the main body and providing power required to drive the rotation angle measuring sensor and the calculating unit.

As such, the present invention provides a spring hanger configured to be fixedly installed in a facility to support the pipe, and to buffer vibration or shock generated by a change in the load of the pipe or thermal expansion/contraction through the tension/compression of the spring installed therein, There is an advantage of measuring the pipe displacement through a simple sensor structure in measuring the pipe displacement in order to determine the abnormal symptom of the pipe.

In addition, in the present invention, by installing a strain gauge on the fixed coupling member for coupling and installing the spring to the hanger body and measuring the deformation of the fixed coupling member, the load transmitted from the pipe-side element can be calculated to determine the abnormality of the pipe. There is an advantage that

1 is a perspective view of a spring hanger according to an embodiment of the present invention;
2 is a partially cut-away perspective view of a spring hanger according to an embodiment of the present invention;
3 is a partially cut-away perspective view of another position of a spring hanger according to an embodiment of the present invention;
4 is a partially cut perspective view in another direction showing a rotation angle measuring sensor and a calculation unit of a spring hanger according to an embodiment of the present invention;
5 is a partially cut-away perspective view of another position of a spring hanger according to an embodiment of the present invention;
6 is a sensor configuration diagram of a spring hanger according to an embodiment of the present invention.

The present invention may be embodied in various other forms without departing from its technical spirit or main characteristics. Accordingly, the embodiments of the present invention are merely illustrative in all respects and should not be construed as limiting.

The terms 1st, 2nd, etc. are used only for the purpose of distinguishing one component from another component. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component.

When a component is referred to as being “connected” or “connected” to another component, it may be directly connected or connected to the other component, but another component may exist in between.

As used herein, the singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as "comprises" or "comprising", "have" and the like are intended to represent the presence of elements or combinations thereof described in the specification, and the possibility that other elements or features may be present or added. It is not precluded.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a perspective view of a spring hanger according to an embodiment of the present invention, FIG. 2 is a partially cut-away perspective view of a spring hanger according to an embodiment of the present invention, and FIG. 3 is a portion in another position of a spring hanger according to an embodiment of the present invention 4 is a partially cut perspective view in another direction showing the rotation angle measuring sensor and calculating part of the spring hanger according to an embodiment of the present invention, FIG. 5 is a part of another position of the spring hanger according to an embodiment of the present invention 6 is a cut-away perspective view of a sensor configuration of a spring hanger according to an embodiment of the present invention.

The spring hanger of this embodiment is fixedly installed in the facility to support the piping side element (P), and the vibration or shock generated by the load change or thermal expansion/contraction of the piping side element (P) is the tension of the spring 20 installed therein. It is configured to buffer through compression and measures the pipe displacement through a simple sensor structure to determine the abnormality of the pipe-side element (P).

Determination of the abnormality of the pipe-side element (P) is, for example, the vertical displacement (L) of the support link member 50 is generated more than a preset reference value, or the vertical displacement (L) greater than the preset reference value is a preset reference It can be determined by whether or not it occurs more frequently than the cycle. Determination of the abnormal symptom of the pipe-side element (P), as another example, it may be determined whether the change pattern of the vertical displacement (L) of the support link member 50 deviates from a preset normal pattern.

To this end, the spring hanger of the present embodiment may basically calculate the vertical displacement L of the support link member 50 based on the measurement result of the rotational displacement R of the first hinge shaft 91 .

The spring hanger of this embodiment has a main body 10, a coiled spring 20, a movable rod 30, a movable link member 40, a support link member 50, a rotation angle measuring sensor 60 and a calculating unit 70. includes

The body 10 includes a cylindrical inner space disposed in the transverse direction. The body 10 may be manufactured in the form of a metal casing.

The coil spring 20 is arranged to be compressed or restored in the cylindrical inner space along the cylindrical axial direction Ax.

One end 30a of the movable rod 30 is coupled to a locking plate 82 disposed outside one end of the coil spring 20, and a through hole formed in one side 10a of the main body 10 ( The other end 30b protrudes outward through 10b).

The movable link member 40 is rotatably coupled to the support member 18 installed on one side 10a of the main body 10 through a first hinge shaft 91, and It is coupled to the other end 30b in a rotatable state through the second hinge shaft 92 .

For example, the support member 18 may be composed of a metal plate attached to one side 10a of the body 10 formed in a cylindrical shape, and two parallel metal plates are provided so that the movable link member 40 can be installed inside. It may be an arranged structure.

A bracket member 19 for fixing and installing a spring hanger to a facility (eg, a ceiling surface, a structural beam) may be installed above the support member 18 .

As an example, the movable link member 40 of this embodiment may be configured in a form in which two metal plates having a substantially triangular shape are arranged in parallel, but is not limited to this form. When the movable link member 40 is formed in a substantially triangular shape, the first hinge shaft 91, the second hinge shaft 92, and the third hinge shaft 93 are parallel at positions adjacent to each vertex of the triangle, respectively. It can be installed to have one axial direction. Axial directions of the first hinge shaft 91 , the second hinge shaft 92 , and the third hinge shaft 93 may be respectively disposed in a direction perpendicular to the axial direction Ax of the cylindrical shape of the body 10 . .

One end 50a of the support link member 50 is coupled to one side (eg, one vertex side of a triangle) of the movable link member 40 in a rotatable state through a third hinge shaft 93, and the other end ( A pipe-side element (P) can be coupled to 50b). As an example, the pipe-side element (P) may be a support bracket for supporting the load of the pipe, but is not limited thereto.

The rotation angle measuring sensor 60 is installed on the support member 18 and receives the rotational state of the first hinge shaft 91 using a mechanism element to receive the rotational displacement of the first hinge shaft 91 ( R) to generate the measurement result.

For example, the mechanism element receives the first gear 62 installed coaxially with the first hinge shaft 91 and the rotational state of the first hinge shaft 91 from the first gear 62, and a second gear 64 for transmitting the rotational state of the first hinge shaft 91 to the rotation angle measuring sensor 60 using the coaxially installed input shaft 60a.

The first gear 62 and the second gear 64 may be directly meshed, or may be meshed through a separate intermediate gear (not shown). A gear ratio of the first gear 62 and the second gear 64 may be determined in consideration of an appropriate resolution of the rotation angle measuring sensor 60 .

As a preferred example, the rotation angle measuring sensor 60 of this embodiment is a magnetic rotary encoder installed inside a waterproof casing (C), and the rotation angle of the magnets (N, S) installed at the input end of the input shaft (60a) It is configured to receive the rotational state of the first hinge shaft 91 based on the change state. This configuration is illustrated in FIG. 4 . Reference numeral 67 denotes a support mechanism for supporting the rotation of the input shaft 60a.

In the case of taking this configuration, the rotation angle measuring sensor 60 is installed inside a waterproof casing, and the magnetic flux change according to the rotation of the magnets (N, S) of the input shaft (60a) located outside the casing (C) signals by Since the rotational state of the first hinge shaft 91 is transmitted by detecting , the rotation angle measuring sensor 60 is not directly exposed to the outside, so there is an advantage in preventing an input error or a risk of failure due to external moisture.

As a modification, the rotation angle measuring sensor 60 may be a known rotary encoder or potentiometer capable of measuring a rotational position by a mechanical input of an input shaft while operating in a rotary type, and in this case, a casing through which the input shaft passes. A configuration for waterproofing the part may be included. In the case of installing the potentiometer, a configuration for calculating the absolute rotational position in consideration of the reference position may be included.

The calculating unit 70 receives the measurement result of the rotational displacement R of the first hinge shaft 91 from the rotation angle measuring sensor 60 and calculates the vertical displacement L of the support link member 50 . do. To this end, the reference position of the rotational displacement R of the first hinge shaft 91 and/or the reference position of the vertical displacement L of the support link member 50 are set, and the mutual conversion relationship between them is calculated by the calculation unit 70 may be preset and stored.

The operation unit 70 includes a known microcontroller unit (MCU) and memory, an input/output interface, an input unit, a power supply unit 120, an output display unit (C1), and a PCB board (PP) for connecting these elements to an electronic circuit. It can be configured in the form of a computing module to calculate the vertical displacement (L) and a computer program for calculating a load as described below is installed and driven. The casing (C) of the computing module is manufactured to have a waterproof structure as described above and may be attached to one side of the support member 18 .

The vertical displacement L of the support link member 50 corresponding to the measurement result of the rotational displacement R of the first hinge shaft 91 is previously stored in the calculator 70 in the form of a matching table, or the first hinge shaft By storing in advance a calculation algorithm for calculating the vertical displacement L of the support link member 50 from the measurement result of the rotational displacement R of (91) in the calculation unit 70 in advance, the calculation unit 70 performs the operation of the support link member 50 ) of the vertical displacement (L) can be calculated.

Meanwhile, referring to FIG. 5 , the spring hanger of this embodiment may calculate the load transmitted from the pipe-side element P using the strain gauge 100 .

To this end, a support plate 84 is disposed on the inside of one side 10a of the main body 10 at a position opposite to the locking plate 82 to support the outer side of the other end of the coil-type spring 20, and , an extension piece 86 extending toward the inner space of the spring coil is integrally formed on one side of the support plate 84 .

In addition, it extends toward the inner space of the spring coil so as to correspond to the extension piece 86, one end 88a is fixedly coupled to the extension piece 86, and the side surface 10a of the main body 10 is A fixed coupling member 88 to which the other end 88b is fixedly coupled is provided on the inside. Reference numeral BT of FIG. 5 is a bolt for fixing the fixing coupling member 88 to the inner side of one side 10a of the body 10, and the symbol CB is a measurement signal from the strain gauge 100 to the calculating unit 70. and the code CP is a fixing pin for fixing the extension piece 86 and the fixing coupling member (88).

The fixed coupling member 88 is provided with a strain gauge 100 for measuring the deformation occurring in the fixed coupling member 88 according to the compressed or restored state of the coiled spring 20 . For example, it can be determined that the greater the deformation in the compression direction in the fixed coupling member 88, the greater the load value of the pipe-side element (P).

The load value of the pipe-side element (P) corresponding to the strain of the fixed coupling member 88 measured by the strain gauge 100 is stored in the calculation unit 70 in advance in the form of a matching table in the form of a matching table, or measured in the strain gauge 100 By storing the calculation algorithm for calculating the load value of the pipe-side element P corresponding to the strain rate of one fixed coupling member 88 in the calculation unit 70 in advance, the calculation unit 70 is calculated from the measurement result of the strain gauge 100 The load transmitted from the pipe-side element P can be calculated.

On the other hand, the spring hanger of this embodiment can supply power by generating power by itself using the photovoltaic module 110 or by connecting an external power line (not shown) to supply power. A power storage device (B) may be installed therein to store and supply the supplied power.

Depending on the characteristics of the facility, it may be difficult to connect and install an external power line (not shown) for each spring hanger, or it may be difficult to maintain and manage the external power line. When the solar power generation module 110 is installed, this difficulty can be solved.

An external power line (not shown) may be used in a shaded area or indoors where sunlight is blocked.

The photovoltaic power generation module 110 is installed on the upper portion of the main body 10 and provides power necessary for driving the rotation angle measuring sensor 60 and the calculating unit 70 .

When the solar power module 110 is installed, the power storage device B may be a rechargeable battery or a supercapacitor that can be charged and discharged, and the power supply unit 120 has a solar power module 110 . A charge/discharge control circuit is further provided for charging and discharging control for the calculating unit 70 and the like.

The spring hanger of this embodiment operates as follows.

In a state in which the other end 50b of the support link member 50 receives an external force in the upward direction (U) or downward direction (D) by the pipe-side element (P), the second hinge shaft 92 and the The third hinge shaft 93 revolves around the first hinge shaft 91 in the first rotation direction R1 or the second rotation direction R2, respectively.

In a state in which the second hinge shaft 92 and the third hinge shaft 93 revolve around the first hinge shaft 91 in the first rotation direction R1 or the second rotation direction R2, respectively. , the other end 30b of the movable rod 30 revolves in the first rotational direction R1 or the second rotational direction R2 together with the second hinge shaft 92, and one end of the movable rod 30 (30a) compresses or restores the coil spring 20 through the locking plate 82. In this process, the other end 30b of the movable rod 30 is moved forward or backward along the cylindrical axial direction Ax and makes an orbital motion about the first hinge shaft 91, The through-hole 10b through which the movable rod 30 passes and the through-hole (not shown) of the movable link member 40 are formed to provide an expanded hole space for the orbital movement.

By compression or restoration of the coiled spring 20, the spring hanger of this embodiment can buffer vibration or shock generated by a load change or thermal expansion/contraction of the pipe-side element P.

In addition, in this process, the calculation unit 70 receives the measurement result of the rotational displacement R of the first hinge shaft 91 from the rotation angle measurement sensor 60 to receive the vertical displacement of the support link member 50 . (L) is calculated.

In addition, in this process, the calculating unit 70 may calculate the load transferred from the pipe-side element P from the measurement result of the strain gauge 100 .

The calculation unit 70 may display the calculated vertical displacement L and/or the load value through the output display means C1, and transmit the calculated value to the remote control means through a communication line (not shown) or It can also generate an alarm signal.

As a preferred example, the calculating unit 70 receives the measurement result of the deformation occurring in the fixed coupling member 88 from the strain gauge 100 and calculates the load transmitted from the pipe-side element P, and the When the vertical displacement L of the support link member 50 exceeds the first preset reference value in a state where the calculated load is less than or equal to the second preset reference value, an alarm signal determined as an abnormality in the piping is generated.

The first reference value is a reference value for determining whether the vertical displacement L of the support link member 50 is within a normal range, and the second reference value is whether the load transmitted from the pipe-side element P is within the normal range. is a standard value for judging

Even though the load transmitted from the pipe-side element P is within the normal range, when the vertical displacement L of the support link member 50 exceeds a preset first reference value, it is a general change in the load. Rather, it can be viewed as a case in which excessive vibration is generated due to thermal expansion/contraction of the pipe-side element (P), and in this case, an alarm signal that is determined as an abnormal symptom of the pipe is generated.

Although the present invention has been mainly described with reference to the accompanying drawings, it will be apparent to those skilled in the art that many various and obvious modifications can be made therefrom without departing from the scope of the present invention. Accordingly, the scope of the present invention should be construed by the appended claims to cover many such modifications.

10: body
18: support member
20: coiled spring
30: movable bar
40: no movable link
50: support link member
60: rotation angle measurement sensor
62: first gear
64: second gear
70: arithmetic unit
82: catch plate
84: support plate
86: extension
88: fixed coupling member
91: first hinge shaft
92: second hinge shaft
93: third hinge shaft
100: strain gauge
110: solar power module
Ax: axial direction
L: vertical displacement
P: pipe side element
R: rotational displacement

Claims (8)

a body including a cylindrical interior space disposed in a transverse direction;
a coil-type spring arranged to be compressed or restored in the cylindrical inner space along the cylindrical axial direction;
a movable rod having one end coupled to a locking plate disposed outside one end of the coil-type spring, and the other end protruding outward through a through hole formed in one side of the body;
a movable link member rotatably coupled to a support member installed on one side of the body through a first hinge shaft and rotatably coupled to the other end of the movable rod through a second hinge shaft;
a support link member having one end coupled to one side of the movable link member in a rotatable state through a third hinge shaft, and a pipe-side element coupled to the other end;
a rotation angle measuring sensor installed on the support member and receiving a rotational state of the first hinge shaft using a mechanism element to measure the rotational displacement of the first hinge shaft; and
A spring hanger having a displacement measuring function configured to include a; calculating unit for receiving the measurement result of the rotational displacement of the first hinge shaft from the rotation angle measurement sensor and calculating the vertical displacement of the support link member.
According to claim 1,
The mechanism element comprises:
a first gear installed coaxially to the first hinge shaft;
and a second gear that receives the rotational state of the first hinge shaft from the first gear and transmits the rotational state of the first hinge shaft to the rotation angle measurement sensor using an input shaft installed coaxially. spring hanger.
3. The method of claim 2,
The rotation angle measurement sensor,
It is a magnetic rotary encoder installed inside a waterproof casing.
A spring hanger having a displacement measuring function, characterized in that it receives the rotational state of the first hinge shaft based on a change in rotational angle of a magnet installed at the input end of the input shaft.
According to claim 1,
In a state in which the other end of the support link member receives an external force in an upward direction or a downward direction by the pipe-side element, the second hinge shaft and the third hinge shaft may respectively rotate in the first rotational direction or in the second rotational direction. A spring hanger having a displacement measurement function, characterized in that it revolves around the hinge axis.
5. The method of claim 4,
In a state in which the second hinge shaft and the third hinge shaft revolve around the first hinge shaft in a first rotational direction or a second rotational direction, respectively,
The other end of the movable rod revolves in a first rotational direction or a second rotational direction together with the second hinge shaft,
One end of the movable rod is a spring hanger having a displacement measuring function, characterized in that for compressing or restoring the coil-type spring through the locking plate.
According to claim 1,
A support plate is provided on the inner side of one side of the main body at a position opposite to the locking plate to support the outer side of the other end of the coil-type spring,
An extension piece extending toward the inner space of the spring coil is integrally formed on one side of the support plate,
A fixed coupling member extending toward the inner space of the spring coil to be disposed in correspondence with the extension piece, one end being fixedly coupled to the extension piece, and the other end being fixedly coupled to the inner side of one side of the body, is provided.
A spring hanger having a displacement measuring function, characterized in that the fixed coupling member is provided with a strain gauge for measuring the deformation occurring in the fixed coupling member according to a state in which the coiled spring is compressed or restored.
7. The method of claim 6,
The calculation unit,
Receives the measurement result of the deformation occurring in the fixed coupling member from the strain gauge and calculates the load transmitted from the pipe-side element,
Displacement measuring function, characterized in that when the vertical displacement of the support link member exceeds a preset first reference value in a state in which the calculated load is less than or equal to a second preset reference value, generating an alarm signal for determining an abnormality in the pipe spring hanger with
According to claim 1,
A spring hanger with a displacement measuring function, characterized in that it further comprises; a solar power module installed on the upper portion of the main body and providing power required to drive the rotation angle measuring sensor and the calculating unit.

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