JP6185736B2 - Thermo valve - Google Patents

Description

  The present invention relates to a thermo valve, and more particularly to a thermo valve that shuts off the supply of liquefied gas to the evaporator when detecting an abnormal temperature drop in the evaporator of liquefied gas such as LPG.

  The liquefied gas such as LPG is supplied continuously to the gas consuming equipment by guiding the liquid liquefied gas contained in a container such as a cylinder to the evaporator, evaporating and raising the temperature in the evaporator. . For example, the evaporator described in Patent Document 1 includes an evaporation section including a heat exchange channel formed of a heat medium such as a metal member heated by a heat source such as an electric heater, and evaporates liquid phase liquefied gas. The gas is introduced into the unit, vaporized, heated, and supplied to the gas consuming device. In addition, a vaporization pressure adjustment valve is provided for controlling the amount of liquefied gas in the liquid phase flowing into the evaporation unit in accordance with fluctuations in gas consumption of the gas consuming device. This vaporization pressure adjustment valve is provided with an adjustment valve that opens and closes the communication path between the inlet pressure chamber of the liquid phase liquefied gas and the inlet pressure chamber of the evaporator, and maintains the pressure in the inlet pressure chamber of the evaporator at a predetermined value. It is comprised so that the opening degree of an adjustment valve may be controlled.

  In such an evaporator, when an abnormality such as a stop of the heat source occurs, there is a possibility that the evaporation capability of the evaporation section is rapidly reduced and the liquid liquefied gas is supplied as it is to the gas consuming device. Therefore, in Patent Document 1, when a temperature drop in the evaporation section is detected, a safety mechanism is provided that quickly closes the thermo valve and blocks the inflow of the liquid phase liquefied gas to the evaporation section. The vaporization pressure regulating valve urges the regulating valve in a direction to close the regulating valve by the resultant pressure of the inlet pressure chamber of the evaporation section and the elastic force of the first spring, and the inlet pressure of the liquid phase liquefied gas and the elasticity of the second spring. It is formed by energizing the regulating valve in the direction of opening the adjusting valve by the resultant force. When the gas consumption increases and the inlet pressure of the evaporation section decreases, the regulating valve opens to increase the inflow of liquid phase liquefied gas, and the gas consumption decreases and the evaporation section inlet pressure increases. The control valve is closed to reduce the inflow of liquid phase liquefied gas. Therefore, in order to reduce the elastic force of the second spring and close the adjustment valve, the security mechanism slides a spring retainer that defines the position of the second spring in the biasing direction of the second spring. Provided with an engagement mechanism that restrains the spring retainer at a predetermined position when the temperature of the evaporation section is in a steady state and releases the restraint when the temperature of the evaporation section drops below the set temperature. Has been.

  In this engagement mechanism, an engagement groove is formed on the sliding surface of the spring presser, and an engagement pin is inserted into a through hole formed in the outer wall of the valve body portion so as to face the engagement groove, and the temperature of the evaporation portion is adjusted. It is formed by pressing the engagement pin in the direction of the engagement groove by a link mechanism that rotates accordingly. As a result, when the temperature of the evaporating portion is steady above the set temperature, the engagement pin engages with the engagement groove and the spring presser is held at the steady position. Further, when the temperature of the evaporation section is abnormally lowered, the engagement pin and the engagement groove are disengaged, the vaporization pressure adjustment valve is closed, and the inflow of the liquid phase liquefied gas to the evaporation section is shut off. It is possible to prevent an abnormality in which the phase liquefied gas is supplied to the gas consuming device.

  Patent Document 1 discloses various safety measures when an abnormality such as a stop of the heat source is resolved after the safety mechanism is activated and the vaporization pressure regulating valve is fully closed, and the evaporation capability of the evaporation unit is restored. After confirmation, a reset mechanism is provided to reset the security mechanism by manual operation. The reset mechanism is configured to return the spring presser to a predetermined position and engage the engagement pin and the engagement groove. In other words, the reset mechanism has a reset pin that is inserted in a reset pin that moves the spring presser back in the direction of pushing back the spring presser from the outer wall surface of the main body of the vaporizing pressure regulating valve, and is rotatably supported by a support member provided on the outer wall of the main body Is formed by abutting one end of the reset pin on one end of the reset pin.

JP-A-11-114405

  According to the security mechanism of Patent Document 1, it is possible to prevent liquid phase liquefied gas from being supplied to the gas consuming device due to a temperature abnormality of the heat source of the evaporation section. In addition, if it is possible to recognize at a glance from the outside that the safety mechanism has been reset, safe driving can be further ensured. In general, it is known to provide a thermo valve that cuts off the supply of the liquefied gas to the vaporization pressure adjustment valve when the temperature of the evaporator that vaporizes the liquefied gas is abnormally lowered by separating the safety mechanism from the vaporization pressure adjustment valve. ing. Also in this case, if it is possible to recognize at a glance from the outside that the thermo valve has been reset, the reliability of safe driving can be further improved.

  The problem to be solved by the present invention is to make it possible to recognize at a glance from the outside the reset state of the thermo valve that shuts off the supply of the liquefied gas to the evaporator when the temperature of the evaporator that vaporizes the liquefied gas drops abnormally. It is in.

In order to solve the above problems, the present invention is a thermo valve that shuts off the supply of liquefied gas to the evaporation section when detecting an abnormal temperature drop of the evaporation section that vaporizes liquid phase liquefied gas, An inlet pressure chamber connected to the inlet of the liquefied gas of the phase, an outlet pressure chamber connected to the outlet of the liquefied gas of the liquid phase, and a main valve that opens and closes the communication path between the inlet pressure chamber and the outlet pressure chamber a first elastic member that urges the main valve in the direction of closing the communication passage, a driving unit for urging the main valve before the direction of opening the Killen passage, the inlet, bypassing the main valve a bypass passage communicating the outlet pressure chamber and the pressure chamber, a bypass valve for opening and closing said bypass passage, said main lower the biasing force of the drive unit when the temperature of the evaporation unit falls below the set temperature A control unit for closing the valve, wherein the bypass valve A valve body that closes, a valve rod that supports the valve body so as to be movable in the open / close direction, a through hole that supports the valve rod in a slidable and airtight manner and that is open on the outer surface of the main body, and the valve rod and a second elastic member for urging the closing direction of the valve body, and a lever pivotally mounted via a pin earlier end of the valve stem that protrudes from the opening of the through hole When the lever is rotated in a predetermined direction, the tip of the lever rotates and is pressed against the outer surface of the main body, and the valve rod is inserted into the through hole by the pressing. since the pull out opening the valve body is the bypass passage, when the force applied to the lever is released, the valve stem presses write or Re in the through-hole by the elastic force of the second elastic member the thermo-valve the valve body is formed so as to close said bypass passage to provide Te.

  In the thermo valve of the present invention, when the temperature of the evaporation unit that vaporizes the liquid phase of the liquefied gas falls below the set temperature, the urging force of the drive unit that urges the main valve in the direction to open the main valve is lowered, Since the main valve is quickly closed by the urging force of the first elastic member, it operates as a security mechanism that prevents liquid-phase liquefied gas from being supplied to the gas consuming device due to a temperature abnormality (decrease) in the heat source of the evaporation section. To do. Once the main valve is closed, the pressure in the inlet pressure chamber is higher than that in the outlet pressure chamber as long as the temperature abnormality (decrease) in the heat source of the evaporator continues, so the main valve is kept fully closed. Thus, the operating state of the safety mechanism is maintained. In this state, even if the temperature abnormality of the heat source of the evaporation section is resolved, the operating state of the safety mechanism is maintained because the pressure in the outlet pressure chamber is lower than that in the inlet pressure chamber.

  After confirming that the temperature abnormality of the heat source in the evaporation unit has been resolved and the safety of the gas consuming equipment, etc., when restarting the steady operation of the evaporator, reset the operating state of the safety mechanism and make the thermo valve operate normally. Need to work. According to the present invention, by rotating the lever and pulling the valve rod of the bypass valve, the bypass passage is opened and the pressure difference between the inlet pressure chamber and the outlet pressure chamber is eliminated. Increased, the main valve is opened and the thermo-valve is reset to a state where it can operate normally. After such a reset is performed, the function of the thermo valve is maintained even if the lever returns and the bypass path is closed. Therefore, in the present invention, when the force applied to the lever is released and the lever is rotated to the initial position, the valve body of the bypass valve is pushed in by the second elastic member to close the bypass path, so that the thermo valve is normal. It is reset to an operable state. Thus, once the lever is pulled, it is automatically reset when the hand is released. Further, since the lever is returned to the predetermined initial position by the second elastic member, the operating state of the reset mechanism can be recognized from the outside at a glance. If the bypass valve is left open at the time of resetting, there is a problem in the protection operation at the next temperature abnormality. In this regard, according to the present invention, the malfunction is prevented because the bypass valve is automatically closed after resetting.

  In the present invention, the lever is configured such that the lever side surface near the pin contacts the outer surface of the main body portion at a position where the valve rod is pushed into the through hole and the valve body closes the bypass passage. It is desirable that it be formed. According to this, the normal state in which the bypass path is closed can be reliably recognized from the outside.

  Moreover, it is preferable that the said valve stem is provided with the engaging part slidably engaged in the groove | channel formed in the said main-body part near opening of the said through-hole. According to this, it is possible to prevent the valve stem from rotating around the axis of the through hole by an external force applied to the lever.

  Further, the lever is preferably formed such that a corner portion of the tip that rotates while being pressed against the outer surface of the main body is formed into a curved surface having a radius that gradually increases around the pin. According to this, the lever can be smoothly rotated, and the valve rod can be smoothly pulled out by the rotation of the lever.

  ADVANTAGE OF THE INVENTION According to this invention, the reset state of the thermovalve which interrupts | blocks supply of the liquefied gas to an evaporator at the time of the abnormal fall of the temperature of the evaporator which vaporizes liquefied gas can be recognized from a glance.

The block diagram of one Example of the thermo valve of this invention is shown. It is a figure which shows the structure of the evaporator to which the thermo valve of the Example of FIG. 1 is applied. It is a figure which shows the structure of the vaporization pressure control valve of the evaporator of FIG.

  Hereinafter, an embodiment of the thermo valve of the present invention will be described with reference to FIGS. As shown in FIG. 2, the evaporator 100 according to the present embodiment includes an evaporation unit 110, a vaporization pressure adjustment valve 130 provided on the evaporation unit 110, and a liquid phase liquefaction supplied to the vaporization pressure adjustment valve 130. The thermo valve 1 provided on the gas inlet side and the controller 150 that controls the electrical equipment provided in the evaporator 100 are provided. The evaporation unit 110 includes a block-shaped heat medium 111 formed of a metal member such as aluminum. The heat medium 111 is formed with a heat exchange channel 112 drilled from the upper surface to the bottom in the drawing, and a bottom space 113 formed in the heat medium 111 in communication with the lower end of the heat exchange channel 112. . The upper end of the heat exchange channel 112 is opened to an evaporation surface 114 formed on the top surface of the heat medium 111.

  In addition, an electric heater 115 as a heat source is provided in the horizontal direction above the heat medium 111. Further, a temperature sensing cylinder 116 for detecting the temperature of the heat medium 111 is inserted into the heat medium 111 above the electric heater 115. Further, a liquefied gas outlet nozzle 117 for supplying the vaporized liquefied gas to a gas consuming device (not shown) is provided in communication with the bottom space 113. A safety valve 119 is connected to the outlet nozzle 117 via a gate valve 118. A drain pipe 121 having a gate valve 120 is connected to the bottom of the bottom space 113.

  As shown in FIG. 3, the vaporization pressure adjustment valve 130 is provided with an adjustment valve 132 that controls the liquid phase liquefied gas blown into the outlet pressure chamber 131 opened in the evaporation surface 114. An inlet 133 of the regulating valve 132 is connected to an outlet of a thermo valve 1 described later so that liquid phase liquefied gas is supplied. The adjustment valve 132 is formed by pressing the valve element 134 against the valve seat 136 with a spring 135. When the valve element 134 is pushed away from the valve seat 136 by the valve rod 137, liquid phase liquefied gas is drawn out from the ejection hole 138 to the outlet pressure chamber 131. On the other hand, a diaphragm 140 is provided facing the pressure chamber 139 communicated with the outlet pressure chamber 131, and the diaphragm 140 is urged downward in the figure by a spring 141. A stem 147 is fixed at the center of the diaphragm 140, and the stem 147 is inserted through a through hole 143 formed in the partition wall 142 of the outlet pressure chamber 131. In the outlet pressure chamber 131, a triangular movable piece 144 is rotatably supported by a support member 145 suspended from the partition wall 142. The tip of the stem 147 is in contact with one side of the movable piece 144, and the tip of the valve rod 137 is in contact with the other side. With this configuration, the vaporizing pressure adjusting valve 130 rotates the movable piece 144 so that the pressure in the outlet pressure chamber 131 balances with the spring 141 set by the adjusting screw 146, thereby causing the valve rod 137 to move. Thus, the valve body 134 is opened and closed to adjust the amount of liquid-phase liquefied gas supplied to the outlet pressure chamber 131.

  Since the evaporator 100 is configured as described above, the evaporator 100 is in the process of contacting the liquid phase liquefied gas ejected from the vaporization pressure regulating valve 130 toward the evaporation surface 114 with the heat medium 111 heated by the electric heater 115, In the course of flowing through the heat exchange channel 112, the gas is vaporized and the temperature is raised, and the gas is supplied to the gas consuming device via the outlet nozzle 117. The electric heater 115 is controlled by the controller 150 based on the temperature of the heat medium 111 detected by the temperature sensing cylinder 116. The vaporization pressure adjustment valve 130 controls the pressure of the outlet pressure chamber 131 to a set pressure following the gas consumption of the gas consuming device, thereby reducing the supply amount of the liquid phase liquefied gas supplied to the evaporation unit 110. Control.

  Next, a thermo valve 1 that is a feature of the present invention will be described with reference to FIG. FIG. 1A is a top view of the thermo valve 1, and FIG. 1B is a cross-sectional view taken along line BB in FIG. As shown in the figure, the thermo valve 1 is formed by using a valve block 2 which is a main body formed in a rectangular parallelepiped shape. The valve block 2 is formed with an inlet pressure chamber 4 communicating with the liquid phase liquefied gas inlet 3 and an outlet pressure chamber 6 communicating with the liquid phase liquefied gas outlet 5. The inlet pressure chamber 4 and the outlet pressure chamber 6 are formed in a cylindrical shape and communicate with each other through an opening. In this embodiment, since the inner diameter of the outlet pressure chamber 6 is smaller than the inner diameter of the inlet pressure chamber 4, a stepped portion 7 is formed on the outlet pressure chamber 6 side of the communication portion between the inlet pressure chamber 4 and the outlet pressure chamber 6. The A main valve comprising a valve body 8 for opening and closing the communication path is formed using the step 7 of the communication path as a valve seat. The valve body 8 is urged in a direction to close the communication path by a spring 16 which is a first elastic member. Further, the valve body 8 is supported by a temperature control unit 10 that is a drive unit that urges the valve body 8 in a direction to open the communication path via the valve rod 9. A bellows 12 formed in a cylindrical shape is accommodated in a cylindrical case 11, and the valve rod 9 is supported on the upper end of the bellows 12 via a bellows receiver 12a, being positioned at the axial center of the bellows 12. The valve stem 9 is slidably inserted into a through hole 13 formed in the valve block 2 via a bushing 13a, and a valve body 8 is fixed to the tip. An O-ring 14 is interposed on the sliding surfaces of the valve stem 9 and the through hole 13 and sealed by this. Further, the nozzle 11 a provided in communication with the case 11 is connected to a heat medium pipe of a temperature sensing cylinder (not shown) that measures the temperature of the heat medium 111 of the evaporator 110 of the evaporator 100. ing. Therefore, the same heat medium as the heat medium (sealed liquid) of the temperature sensing cylinder flows into the outer peripheral side of the bellows 12 and the bellows receiver 12a inside the case 11.

Next, the reset mechanism of the thermo valve 1 will be described. In this embodiment, a bypass passage 15 is provided that bypasses the valve body 8 constituting the main valve and communicates the inlet pressure chamber 4 and the outlet pressure chamber 6. The bypass passage 15 is formed by bending in a bowl shape, and a bypass valve for opening and closing the bypass passage 15 is provided at the bent portion. The bypass valve includes a valve body 17 that opens and closes the bypass passage, a valve rod 18 that supports the valve body 17 so as to be movable in the opening and closing direction, and a through hole 19 that supports the valve rod 18 on the valve block 2 in a slidable and airtight manner. Formed from. The through hole 19 is opened on the outer surface of the valve block 2 which is a main body. The valve rod 18 includes a small diameter portion 18a fixed to the valve body 17, a medium diameter portion 18b following the small diameter portion 18a, a large diameter portion 18c following the medium diameter portion 18b, and a medium diameter portion 18d following the large diameter portion 18c. It is formed. An O-ring is attached to the outer periphery of the small diameter portion 18a. The through hole 19 corresponding to the large diameter portion 18c is formed so that the large diameter portion 18c can slide in the axial direction. A flange 20 is attached to the valve block 2 by a bolt 21 at the opening end of the through hole 19. The flange 20 has a cylindrical portion 20a inserted into the through hole 19, and is formed on the inner peripheral surface of the cylindrical portion 20a to accommodate a spring 25 that is a second elastic member. One end of the spring 25 abuts on the large diameter portion 18c of the valve stem 18,
The other end is attached in contact with a stepped portion 20b formed on the inner peripheral surface of the cylindrical portion 20a. As a result, the valve element 17 biases the valve rod 18 in the direction in which the bypass passage 15 is closed.

  On the other hand, the lever 23 is rotatably attached to the end of the valve rod 18 projecting from the open end of the through hole 19, that is, the through hole 20 c provided extending in the flange 20 in this embodiment through a pin 22. Has been. The end 18e of the valve stem 18 is formed to have a pair of flat plates 24a, b formed with a space therebetween, and is connected by a pin 22 by inserting a lever 23 between the pair of flat plates 24a, b. Yes. Therefore, when the lever 23 is rotated in a predetermined direction A shown in the figure, the tip 23a of the lever 23 is rotated and pressed against the outer surface of the flange 20 fixed to the valve block 2 as the main body. Is done. As a result, the valve stem 18 slides in the direction of being pulled out from the through hole 19 and the through hole 20 c, and the valve body 17 opens the bypass path 15. When the force applied to the lever 23 is released, the valve rod 18 is pushed into the through hole 19 by the spring 25 that is the second elastic member. Thereby, the valve body 17 closes the bypass path 15.

  Here, the lever 23 is a position where the valve rod 18 is pushed into the through hole 19 and the valve body 17 closes the bypass passage 15, and the lever side surface in the vicinity of the pin 22 has a flange 20 corresponding to the outer surface of the main body. It is formed so as to contact the outer surface. Thereby, the normal state in which the bypass path 15 is closed can be reliably recognized from the outside. In the lever 23, the shape of the corner portion of the tip 23 a that rotates while being pressed against the outer surface of the flange 20 is formed as a curved surface having a radius that gradually increases around the pin 22. Accordingly, the lever 23 can be smoothly rotated, and the valve rod 18 can be smoothly pulled out by the rotation of the lever 23. Although not shown, the valve stem 18 has a groove formed in the vicinity of the opening of the through hole 19 and the through hole 20c of the flange 20, and includes an engaging portion slidably engaged in the groove. Preferably it is. According to this, it is possible to prevent the valve rod 18 from rotating around the axis of the through hole 19 due to an external force applied to the lever 23.

  Thus, according to the thermo valve 1 of the present embodiment, when the temperature of the evaporation unit 110 that vaporizes the liquid phase liquefied gas falls below a set temperature (for example, 38 ° C.), the temperature The sealed liquid in the temperature sensitive cylinder connected to the case of the control unit 10 contracts. As a result, the bellows 12 extends, and the urging force of the temperature control unit 10 that is a driving unit that urges the valve body 8 in the opening direction is reduced. As a result, the valve body 8 quickly closes the communication portion between the inlet pressure chamber 4 and the outlet pressure chamber 6 by the biasing force of the spring 16 that is the first elastic member. Therefore, it operates as a security mechanism that prevents the liquid phase liquefied gas from being supplied to the gas consuming device due to the abnormal temperature drop of the heat source of the evaporation unit 110.

  Here, once the valve body 8 of the main valve is closed, the pressure in the inlet pressure chamber 4 is higher than that in the outlet pressure chamber 6 as long as the temperature abnormality of the heat source of the evaporator 110 continues to be reduced. The fully closed state is maintained and the operating state of the safety mechanism is maintained. In this state, even if the temperature abnormality of the heat source of the evaporation unit 110 is resolved, the pressure of the outlet pressure chamber 6 is lower than that of the inlet pressure chamber 4, so that the fully closed state of the valve body 8 is maintained and the operating state of the safety mechanism is maintained. Is maintained.

  Then, after confirming that the temperature abnormality of the heat source of the evaporation unit 110 has been resolved and the safety of the gas consuming device or the like, when the steady operation of the evaporator 100 is resumed, the operating state of the thermo valve 1 that is a safety mechanism is changed. It is necessary to reset and operate the thermo valve 1 normally. According to this embodiment, by rotating the lever 23 and pulling out the valve rod 18 of the bypass valve, the bypass passage 15 is opened and the pressure difference between the inlet pressure chamber 4 and the outlet pressure chamber 6 is eliminated. As a result, the urging force of the valve rod 9 is increased by the temperature control unit 10 to open the valve body 8, and the thermo valve 1 is reset to a state in which it can operate normally. After such a reset is performed, the function of the thermo valve 1 is maintained even if the lever 23 returns and the bypass path 15 is closed. Further, in this embodiment, when the force applied to the lever 23 is released and the lever 23 is rotated to the initial position, the valve body 17 is pushed by the spring 25 and the bypass passage 15 is closed, so that the thermo valve 1 is normal. It is reset to an operable state. That is, once the lever 23 is pulled and then released, it is automatically reset. Further, since the lever 23 is returned to the predetermined initial position by the spring 25, the operating state of the reset mechanism can be recognized at a glance from the outside. If the bypass 15 is left open at the time of resetting, there is a problem in the protection operation at the next temperature abnormality. In this respect, according to the present embodiment, after the reset, the bypass path 15 is automatically closed, so that malfunction can be prevented.

DESCRIPTION OF SYMBOLS 1 Thermo valve 2 Valve block 3 Inlet 4 Inlet pressure chamber 5 Outlet 6 Outlet pressure chamber 7 Communication path 8 Valve body 9 Valve rod 10 Temperature control part 11 Case 12 Bellows 12a Bellows receiver 13 Through-hole 13a Bushing 15 Bypass path 17 Valve body 18 Valve rod 19 Through hole 20 Flange 22 Pin 23 Lever 23a Tip 24a, b Flat plate 25 Spring

Claims (4)

A thermo valve that shuts off the supply of the liquefied gas to the evaporating section when detecting an abnormal temperature drop of the evaporating section that vaporizes the liquid phase liquefied gas,
An inlet pressure chamber communicated with the liquid phase liquefied gas inlet, an outlet pressure chamber communicated with the liquid phase liquefied gas outlet, and a main valve that opens and closes the communication path between the inlet pressure chamber and the outlet pressure chamber A first elastic member that urges the main valve in a direction to close the communication path, a drive unit that urges the main valve in a direction to open the communication path, and bypasses the main valve to the inlet a bypass passage communicating the outlet pressure chamber and the pressure chamber, a bypass valve for opening and closing said bypass passage, said main lower the biasing force of the drive unit when the temperature of the evaporation unit falls below the set temperature It has a control unit that closes the valve,
The bypass valve includes a valve body that opens and closes the bypass passage, a valve rod that supports the valve body so as to be movable in the opening and closing direction, and the valve rod that is slidably and airtightly supported and that is open on the outer surface of the main body. a through hole that is, rotating the valve stem through the second elastic member and a pin earlier end of the valve stem that protrudes from the opening of the through hole to bias in the closing direction of the valve body With an attached lever,
Of said lever, when said lever is rotated in a predetermined direction, the tip of the lever is pressed against the outer surface of the body portion pivots, leaving the valve stem by pressing against it off from the through hole is open the valve body is the bypass path, when the force applied to the lever is released, the second by the elastic force of the elastic member pressing the valve rod in the through-hole write or are in the valve A thermo valve formed so that a body closes the bypass passage.   The lever is formed such that a lever side surface near the pin is in contact with an outer surface of the main body at a position where the valve rod is pushed into the through hole and the valve body closes the bypass passage. The thermo valve according to claim 1.   The thermo valve according to claim 1, wherein the valve stem includes an engaging portion slidably engaged in a groove formed in the main body near the opening of the through hole. .   2. The lever according to claim 1, wherein a corner portion of the tip that is slid and rotated by an outer surface of the main body is formed into a curved surface having a radius that gradually increases with the pin as a center. Thermo valve.

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