WO2008069514A1

WO2008069514A1 - Valve locking device

Info

Publication number: WO2008069514A1
Application number: PCT/KR2007/006181
Authority: WO
Inventors: Young Nam Kim
Original assignee: Youngil Electronic Co., Ltd.
Priority date: 2006-12-04
Filing date: 2007-12-03
Publication date: 2008-06-12
Also published as: KR100803088B1

Abstract

Provided is a valve locking device (200) which includes: a lower body (210) in which a first hole (213) through which a nut engagement portion (150) pierces is formed, and at one side of the lower portion of which a protruding piece (211) which protrudes vertically downwards is formed, and which restricts rotation of the operation lever (130) by the protruding piece (211) and the locking protrusion portion (113); an upper body (230) in which an accommodation groove (231) that accommodates the upper portion of the nut engagement portion (150) is formed and which is combined with the lower body (210); and a locker (220) which is provided so as to slidably move in the horizontal direction by a release unit (250) having a magnetic force between the lower body (210) and the upper body (230) wherein one end (A) of the locker (220) is inserted into the locking groove (153) of the nut engagement portion (150) when the upper portion of the nut engagement portion (150) is accommodated in the accommodation groove (231) of the upper body (230), with a result that the lower body (210) is not separated from the valve (100), and the one end (A) of the locker (220) having been inserted into the locking groove (153) of the nut engagement portion (150) is detached from the locking groove (153) when the locker (220) is slid in the horizontal direction by the release unit (250), with a result that the lower body (210) is separated from the valve (100).

Description

Description VALVE LOCKING DEVICE

Technical Field

[1] The present invention relates to a valve locking device, and more particularly to a valve locking device which can prevent an accident beforehand by preventing an opening and closing valve which is used for controlling flow of a variety of fluids from being manipulated by other persons, unlike a valve handling operator's intention and which can easily perform an opening and closing action of the opening and closing valve. Background Art

[2] In general, valves are installed along a pipe channel or in a vessel, respectively, and are used for controlling a flux or pressure of a fluid such as liquified natural gas (LNG), liquefied petroleum gas (LPG), fuel of liquid phase, and tap water, respectively.

[3] Ball valves are mainly used as valves that control the flux or pressure of a fluid.

[4] In the case of the respective ball valves, a spherical ball having a throughhole is installed along a fluid path of a valve main body, and this ball closely contacts a ball support ring arranged in the fluid path and is linked to an operation lever to thus enable a user to control the ball to rotate.

[5] When the operation lever is rotated left or right, the ball valve opens or closes a fluid path to thereby control various fluids.

[6] According to the conventional art, a locking device is not provided in valves which are used to control a fluid, that is, the flux or pressure of the fluid. A third party other than a valve handling operator can easily manipulate the operation lever to accordingly lead to an accident. Disclosure of Invention Technical Problem

[7] Therefore, to solve the above problems, it is an object of the present invention to provide a valve locking device that can prevent an accident beforehand since a third party having no release unit cannot operate an operation lever of a valve, in which a spherical ball is rotatably provided in the inside of a valve main body, an operation lever that controls a rotational operation of a rotating shaft is coupled with and fixed to the rotating shaft which is integrally connected with the ball, a locking groove is formed in the outer circumference of a nut engagement portion by which the operation lever is coupled with and fixed to the rotating shaft, and a locker is slidably provided in the horizontal direction by the release unit having a magnetic force and is inserted into or separated from the locking groove of the nut engagement portion.

[8] It is another object of the present invention to provide a valve locking device which facilitates attachment and detachment of the valve locking device to and from a valve, in which since the valve locking device is made close to the lower direction of a position where a nut engagement portion is located to thus make the valve locking device mounted on the valve, a special tool is not necessary to mount the valve locking device on the valve, and the valve locking device can be mounted on the valve rapidly and easily, and a release unit having a magnetic force is made close to the side of the valve locking device to thus make the valve locking device detached from and attached to the valve. Technical Solution

[9] To accomplish the above objects of the present invention, according to an aspect of the present invention, there is provided a valve locking device for locking a valve comprising: a valve main body in which a spherical ball is installed; a rotating shaft which is connected to the ball and protruded to the upper portion of the valve main body, for opening and closing a valve; an operation lever which is combined with the rotating shaft and which enables a valve handling operator to manipulate a rotational action of the rotating shaft; a protruding tubular case in which the rotating shaft is inserted which is formed on the upper portion of the valve main body; and a locking protrusion portion which is protruded in the upper portion of the protruding tubular case, to thereby control flux of a fluid by controlling rotational radius of the operation lever by the locking protrusion portion, the valve locking device comprising:

[10] a nut engagement portion around the outer circumference of which a locking groove is formed and which makes the operation lever fixed to and combined with the rotating shaft;

[11] a lower body in which a first hole through which the nut engagement portion pierces is formed, and at one side of the lower portion of which a protruding piece which protrudes vertically downwards is formed, and which restricts rotation of the operation lever by the protruding piece and the locking protrusion portion;

[12] an upper body in which an accommodation groove that accommodates the upper portion of the nut engagement portion is formed and which is combined with the lower body; and

[13] a locker which is provided so as to slidably move in the horizontal direction by a release unit having a magnetic force between the lower body and the upper body wherein one end of the locker is inserted into the locking groove of the nut engagement portion when the upper portion of the nut engagement portion is accommodated in the accommodation groove of the upper body, with a result that the lower body is not separated from the valve, and the one end of the locker having been inserted into the locking groove of the nut engagement portion is detached from the locking groove when the locker is slid in the horizontal direction by the release unit, with a result that the lower body is separated from the valve.

[14] Preferably but not necessarily, the locker comprises: a moving plate of a magnetic substance in which a second hole through which the upper portion of the nut engagement portion pierces is formed, and which slidably moves in the horizontal direction by the release unit, and in which one end of the inner edge of the second hole is inserted into and separated from the locking groove; and an elastic portion which gives an elastic force so that the first hole of the lower body and the second hole of the moving plate are located on an identical axis.

[15] Preferably but not necessarily, the seconds hole of the moving plate is formed of an elongate hole in which a large-diameter portion and a small-diameter are gradually reduced in diameters lengthily in the horizontal direction and are connected with each other, to thus make the edge of the small-diameter portion of the moving plate inserted into and locked into the locking groove of the nut engagement portion by the elastic force of the elastic portion, and the moving plate moves horizontally by the magnetic force of the release unit, to thus make the nut engagement portion separated from the lower body through the large-diameter portion.

[16] Preferably but not necessarily, a curved portion is formed at one side of the operation lever so that the operation lever may rotate along the inner surface of the locking protrusion portion and a locking tap and a locking piece are formed at one end and the other end of the curved portion so as to be locked with the locking protrusion portion, and one end of the protruding piece of the lower body contacts the locking tap or the locking piece, and the other end of the protruding piece contacts the outer surface of the locking protrusion portion to thus restrict rotation of the operation lever.

[17] Preferably but not necessarily, the nut engagement portion comprises: a nut portion around the inner circumferential surface of which a thread is formed and which makes the operation lever fixed to and coupled with the rotating shaft; a nut upper body portion which is extended upwards from the nut portion, and which has an outer diameter smaller than that of the nut portion; and a locking groove formed between the nut portion and the nut upper body.

Advantageous Effects

[18] As described above, a valve locking device according to the present invention can prevent an accident beforehand since a third party having no release unit cannot operate an operation lever of a valve, in which a spherical ball is rotatably provided in the inside of a valve main body, an operation lever that controls a rotational operation of a rotating shaft is coupled with and fixed to the rotating shaft which is integrally connected with the ball, a locking groove is formed in the outer circumference of a nut engagement portion by which the operation lever is coupled with and fixed to the rotating shaft, and a locker is slidably provided in the horizontal direction by the release unit having a magnetic force and is inserted into or separated from the locking groove of the nut engagement portion, and which facilitates attachment and detachment of the locker from the valve. Brief Description of the Drawings

[19] The above and/or other objects and/or advantages of the present invention will become more apparent by describing the preferred embodiments thereof in detail with reference to the accompanying drawings in which:

[20] FIG. 1 is an exploded perspective view showing a valve locking device according to the present invention;

[21] FIG. 2 is a perspective view showing a valve locking device according to the present invention;

[22] FIG. 3 is an exploded perspective view showing a locker according to the present invention;

[23] FIG. 4 is a cross-sectional view of the nut engagement portion according to the present invention;

[24] FIG. 5 is a plan view showing a moving plate according to the present invention;

[25] FIGS. 6 to 8 are perspective views for explaining the operational state of the moving plate and the lower body according to the present invention, respectively;

[26] FIGS. 9 to 11 are cross-sectional views for explaining the operations of a locker according to the present invention, respectively; and

[27] FIG. 12 is a perspective view of a valve in which a valve locking device is mounted in order to keep the valve in an opened state. Best Mode for Carrying Out the Invention

[28] Hereinbelow, a valve locking device according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings. Like reference numerals denote like elements through the following embodiments.

[29] As illustrated in FIGS. 1 to 11, a valve locking device 200 for locking a valve 100 according to the present invention includes a nut engagement portion 150 around the outer circumference of which a locking groove 153 is formed and which makes an operation lever 130 fixed to and combined with a rotating shaft 120, and a locker 220.

[30] The valve 100 includes: a valve main body 110 in which a spherical ball is installed; a rotating shaft 120 which is connected to the ball and protruded to the upper portion of the valve main body 110, for opening and closing a valve; an operation lever 130 which is combined with the rotating shaft 120 and which enables a valve handling operator to manipulate a rotational action of the rotating shaft 120; a protruding tubular case 111 in which the rotating shaft 120 is inserted and which is formed on the upper portion of the valve main body 110; and a locking protrusion portion 113 which is protruded in the upper portion of the protruding tubular case 111, to thereby control flux of a fluid by controlling rotational radius of the operation lever 130 by the locking protrusion portion 113.

[31] As shown in FIGS. 1 to 5, and 11, the valve locking device 200 includes: a nut engagement portion 150 around the outer circumference of which a locking groove 153 is formed and which makes the operation lever 130 fixed to and combined with the rotating shaft 120; a lower body 210 in which a first hole 213 through which the nut engagement portion 150 pierces is formed, and at one side of the lower portion of which a protruding piece 211 which protrudes vertically downwards is formed, and which restricts rotation of the operation lever 130 by the protruding piece 211 and the locking protrusion portion 113; an upper body 230 in which an accommodation groove 231 that accommodates the upper portion of the nut engagement portion 150 is formed and which is combined with the lower body 210; and a locker 220 which is provided so as to slidably move in the horizontal direction by a release unit 250 having a magnetic force between the lower body 210 and the upper body 230 wherein one end "A" of the locker 220 is inserted into the locking groove 153 of the nut engagement portion 150 when the upper portion of the nut engagement portion 150 is accommodated in the accommodation groove 231 of the upper body 230, with a result that the lower body 210 is not separated from the valve 100, and the one end "A" of the locker 220 having been inserted into the locking groove 153 of the nut engagement portion 150 is detached from the locking groove 153 when the locker 220 is slid in the horizontal direction by the release unit 250, with a result that the lower body 210 is separated from the valve 100.

[32] The locker 220 includes: a moving plate 221 of a magnetic substance in which a second hole 223 through which the upper portion of the nut engagement portion 150 pierces is formed, and which slidably moves in the horizontal direction by the release unit 250, and in which one end of the inner edge of the second hole 223 is inserted into and separated from the locking groove 153; and an elastic portion 225 which gives an elastic force so that the first hole 213 of the lower body 210 and the second hole 223 of the moving plate 221 are located on an identical axis.

[33] As shown in FIG. 5, the seconds hole 223 of the moving plate 221 is formed of an elongate hole in which a large-diameter portion 223a and a small-diameter 223b are gradually reduced in diameters lengthily in the horizontal direction and are connected with each other, to thus make the edge of the small-diameter portion 223b of the moving plate 221 inserted into and locked into the locking groove 153 of the nut engagement portion 150 by the elastic force of the elastic portion 225, and the moving plate 221 moves horizontally by the magnetic force of the release unit 250, to thus make the nut engagement portion 150 separated from the lower body 210 through the large-diameter portion 223a.

[34] As shown in FIGS. 1 and 2, a curved portion 131 is formed at one side of the operation lever 130 so that the operation lever 130 may rotate along the inner surface of the locking protrusion portion 113 and a locking tap 133 and a locking piece 135 are formed at one end and the other end of the curved portion 131 so as to be locked with the locking protrusion portion 113, and one end of the protruding piece 211 of the lower body 210 contacts the locking tap 133 or the locking piece 135, and the other end of the protruding piece 211 contacts the outer surface of the locking protrusion portion 113 to thus restrict rotation of the operation lever 130.

[35] As shown in FIGS. 1 and 4, the nut engagement portion 150 includes: a nut portion

151 around the inner circumferential surface of which a thread is formed and which makes the operation lever fixed to and coupled with the rotating shaft; a nut upper body portion 155 which is extended upwards from the nut portion 151, and which has an outer diameter smaller than that of the nut portion 151; and a locking groove 153 formed between the nut portion 151 and the nut upper body 155.

[36] In addition, the nut upper body 155 of the nut engagement portion 150 is gradually reduced in diameter upwards, or the upper portion of the nut upper body 155 in the nut engagement portion 150 is sharply formed.

[37] In addition, a mount groove 215 and an elastic accommodation groove 217 are formed on the upper surface of the lower body 210 in which the moving plate 221 is mounted in the mount groove 215 and the elastic portion 225 is accommodated in the elastic accommodation groove 217.

[38] The operation of the valve locking device having the above-described structure will follow.

[39] As illustrated in FIGS. 1 and 2, a valve 100 is installed along a pipe channel or in a vessel and is used for controlling a flux or pressure of a fluid such as liquified natural gas (LNG), liquefied petroleum gas (LPG), fuel of liquid phase, and tap water, according to a rotational operation of an operation level 130.

[40] The valve 100 includes a valve main body 110 in which a spherical ball (not shown) is installed. An engagement hole 137 of an operation lever 130 is fitted into a moving protrusion portion 121 of a rotating shaft 120 which is integrally connected to the ball (not shown) and protruded to the upper portion of the valve main body 110, for opening and closing the valve 100. Accordingly, the operation lever 130 is combined with the rotating shaft 120. Then, a washer 140 is fitted through the upper end of the rotating shaft 120 with which the operation lever 130 has been combined. Then, the nut engagement portion 150 is engaged with the rotating shaft 120. Accordingly, the operation lever 120 is fixed to and coupled with the rotating shaft 120. Thus, a valve handling operator rotationally manipulates the operation lever 130 to perform a rotational action of the rotating shaft 120, to accordingly control opening and closing of the valve 100. For example, if the operation lever 130 is located perpendicularly with the valve main body 110, as shown in FIG. 1, the spherical ball in the valve 100 blocks a flow of a fluid in the valve 100. Reversely, if the operation lever 130 is located in parallel with the valve main body 110, the valve 100 is opened. When the valve 100 is opened or closed by rotational operation of the operation lever 130, a curved portion 131 of the operation lever 130 is rotated along the inner surface of the locking protrusion portion 113 of the valve main body 110. Accordingly, a locking tap 133 and a locking piece 135 of the operation lever 130 are locked with the locking protrusion portion 113, respectively. As a result, the operation lever 130 is rotated by 90 degrees.

[41] As illustrated in FIGS. 1 to 3, in the case that the valve 100 is closed, and an opening of the valve 100 is intentionally prevented, a valve locking device 200 according to the present invention in which a lower body 210, a locker 220 and an upper body 230 have been combined is mounted vertically downwards on a nut upper body portion 155 of the nut engagement portion 150. In this case, one end 21 Ia of a protruding piece 211 in the lower body 210 contacts the locking tap 113, and the other end 21 Ib of the protruding piece 211 contacts the outer surface of the locking protrusion portion 113. In addition, the valve locking device 200 is mounted on the valve 100 so that the nut upper body portion 155 is accommodated in an accommodation groove 231 of the upper body 230.

[42] As illustrated in FIGS. 6 and 9, the valve locking device 200 according to the present invention is initially positioned at the state where the moving plate 221 is moved horizontally to the right-hand direction by an elastic force of the elastic portion 225 in the locker 220. Accordingly, the second hole 223 of the moving plate 221 is not located on an identical axis with the first hole 213 of the lower body 210. As shown in FIGS. 7 and 10, the valve locking device 200 according to the present invention is mounted on the valve 100. Here, the upper surface of the nut upper body portion 155 in the nut engagement portion 150 is sharply formed. Accordingly, if the valve locking device 200 is mounted on the valve 100 vertically downwards, the upper surface of the nut upper body portion 155 pushes the inner edge "A" of the second hole 223 of the moving plate 221 in the left-hand direction. As a result, the elastic portion 225 is compressed, and the moving plate 221 is moved to the left side, so that the second hole 223 of the moving plate 221 and the first hole 213 of the lower body 210 are located on an identical axis. After that, if the locking groove 153 of the nut engagement portion 150 is located at the second hole 223 of the moving plate 221, the compressed elastic portion 225 is restored and the moving plate 221 is moved to the right side again. As a result, the inner edge "A" of the second hole 223 is inserted into the locking groove 153 of the nut engagement portion 150 and thus the valve locking device 200 is not detached from the valve 100.

[43] Therefore, the valve locking device 200 is combined with the valve 100, and both ends 211a and 21 Ib of the protruding piece 211 of the valve locking device 200 are fixed to the locking tap 133 of the operation lever 130 and the locking protrusion portion 113 of the valve 100, respectively. As a result, the other persons other than a valve handling operator cannot operate the operation lever 130 to thus prevent an accident beforehand.

[44] As illustrated in FIG. 5, the seconds hole 223 of the moving plate 221 is formed of an elongate hole in which a large-diameter portion 223a and a small-diameter 223b are gradually reduced in diameters lengthily in the horizontal direction and are connected with each other. Accordingly, when the valve locking device 200 is mounted on the valve 100, the nut upper body portion 155 of the nut engagement portion 150 is pierced through the large-diameter portion 223a, and the edge "A" of the small- diameter portion 223b is inserted into the locking groove 153 of the nut engagement portion 150 by the elastic force of the elastic portion 225. As a result, the valve locking device 200 is easily mounted on the valve 100, when the valve locking device 200 is mounted on the valve 100, and the valve locking device 200 is not separated from the valve 100, after the valve locking device 200 has been mounted on the valve 100.

[45] In addition, as illustrated in FIG. 3, a mount groove 215 and an elastic accommodation groove 217 are formed on the upper surface of the lower body 210. Accordingly, the moving plate 221 is mounted into the mount groove 215. As a result, the moving plate 221 is horizontally moved in the mount groove 215 by the elastic force of the elastic portion 225, and the elastic portion 225 is accommodated in the elastic accommodation groove 217, to thus prevent the elastic portion 225 from being seceded from the elastic accommodation groove 217. In addition, a projection 221a is formed on the side of the moving plate 221. Accordingly, one end of the elastic portion 225 is combined with the projection 221a, and thus the moving plate 221 is horizontally moved. A spring having an elastic force is used as the elastic portion 225.

[46] In addition, engagement holes 219a and 219b are formed vertically upwards in one side of the lower portion of the lower body 210, and thread holes 233a and 233b are formed in one side of the lower portion of the upper body 210. Then, union screws 240a and 240b are engaged with the thread holes 233a and 233b of the upper body 230 through the engagement holes 219a and 219b of the lower body 210, to thus make the upper body 230 and the lower body 210 coupled with and engaged with each other.

[47] As described above, in the case that the valve locking device 200 is fixed to and coupled with the valve 100, and then a valve handling operator intends to open the valve 100, the release unit 250 having a magnetic force is made to be located near the elastic accommodation groove 217 that accommodates the elastic portion 225, as shown in FIG. 11. Accordingly, the moving plate 221 that is a magnetic substance is horizontally moved to the left side by the magnetic force of the release unit 250 as illustrated in FIGS. 8 and 11. As a result, the elastic portion 225 is compressed and the edge "A" of the small-diameter portion 223b in the moving plate 221 which has been inserted into the locking groove 153 of the nut engagement portion 150 is seceded from the locking groove 153. Accordingly, a valve handling operator can easily separate the valve locking device 200 from the valve 100 through the large-diameter portion 223a in the moving plate 221. After having separated the valve locking device 200 from the valve 100, the valve handling operator rotationally drives the operation lever 130 to thus open the valve 100.

[48] Therefore, a valve locking device facilitates attachment and detachment of the valve locking device to and from a valve, in which since the valve locking device is made close to the lower direction of a position where a nut engagement portion is located to thus make the valve locking device mounted on the valve, a special tool is not necessary to mount the valve locking device on the valve, and the valve locking device can be mounted on the valve rapidly and easily, and a release unit having a magnetic force is made close to the side of the valve locking device to thus make the valve locking device detached from and attached to the valve.

[49] FIG. 12 illustrates a case that a valve 100 is kept in an opened state, and the valve locking device 200 is mounted on the valve 100 so that a third party except a valve handling operator does not close the valve 100. This case is identical with the case that the valve 100 is kept in a closed state, and the valve locking device 200 is mounted on the valve 100 so that a third party except the valve handling operator does not open the valve 100. However, one end 21 Ia of the protruding piece 211 of the lower body 210 contacts the outer surface of the locking protrusion portion 113, and the other end 21 Ib of the protruding piece 211 contacts the locking piece 135 to thus restrict the rotational operation of the operation lever 130. Mode for the Invention

[50] As described above, the present invention has been described with respect to particularly preferred embodiments. However, the present invention is not limited to the above embodiments, and it is possible for one who has an ordinary skill in the art to make various modifications and variations, without departing off the spirit of the present invention. Thus, the protective scope of the present invention is not defined within the detailed description thereof but is defined by the claims to be described later and the technical spirit of the present invention. Industrial Applicability

[51] As described above, a valve locking device according to the present invention is used for controlling flow of a variety of fluids from being manipulated by other persons, unlike a valve handling operator's intention so as to prevent an accident beforehand by preventing an opening and closing valve which and to easily perform an opening and closing action of the opening and closing valve.

Claims

[1] A valve locking device (200) for locking a valve (100) comprising: a valve main body (110) in which a spherical ball is installed; a rotating shaft (120) which is connected to the ball and protruded to the upper portion of the valve main body (110), for opening and closing a valve; an operation lever (130) which is combined with the rotating shaft (120) and which enables a valve handling operator to manipulate a rotational action of the rotating shaft (120); a protruding tubular case (111) in which the rotating shaft (120) is inserted and which is formed on the upper portion of the valve main body (110); and a locking protrusion portion (113) which is protruded in the upper portion of the protruding tubular case (111), to thereby control flux of a fluid by controlling rotational radius of the operation lever by the locking protrusion portion, the valve locking device comprising: a nut engagement portion (150) around the outer circumference of which a locking groove (153) is formed and which makes the operation lever (130) fixed to and combined with the rotating shaft (120); a lower body (210) in which a first hole (213) through which the nut engagement portion (150) pierces is formed, and at one side of the lower portion of which a protruding piece (211) which protrudes vertically downwards is formed, and which restricts rotation of the operation lever (130) by the protruding piece (211) and the locking protrusion portion (113); an upper body (230) in which an accommodation groove (231) that accommodates the upper portion of the nut engagement portion (150) is formed and which is combined with the lower body (210); and a locker (220) which is provided so as to slidably move in the horizontal direction by a release unit (250) having a magnetic force between the lower body (210) and the upper body (230) wherein one end (A) of the locker (220) is inserted into the locking groove (153) of the nut engagement portion (150) when the upper portion of the nut engagement portion (150) is accommodated in the accommodation groove (231) of the upper body (230), with a result that the lower body (210) is not separated from the valve (100), and the one end (A) of the locker (220) having been inserted into the locking groove (153) of the nut engagement portion (150) is detached from the locking groove (153) when the locker (220) is slid in the horizontal direction by the release unit (250), with a result that the lower body (210) is separated from the valve (100).

[2] The valve locking device according to claim 1, wherein the locker (220) comprises: a moving plate (221) of a magnetic substance in which a second hole (223) through which the upper portion of the nut engagement portion (150) pierces is formed, and which slidably moves in the horizontal direction by the release unit (250), and in which one end of the inner edge of the second hole (223) is inserted into and separated from the locking groove (153); and an elastic portion (225) which gives an elastic force so that the first hole (213) of the lower body (210) and the second hole (223) of the moving plate (221) are located on an identical axis.

[3] The valve locking device according to claim 2, wherein the seconds hole (223) of the moving plate (221) is formed of an elongate hole in which a large-diameter portion (223a) and a small-diameter (223b) are gradually reduced in diameters lengthily in the horizontal direction and are connected with each other, to thus make the edge of the small-diameter portion (223b) of the moving plate (221) inserted into and locked into the locking groove (153) of the nut engagement portion (150) by the elastic force of the elastic portion (225), and the moving plate (221) moves horizontally by the magnetic force of the release unit (250), to thus make the nut engagement portion (150) separated from the lower body (210) through the large-diameter portion (223 a).

[4] The valve locking device according to claim 1, wherein a curved portion (131) is formed at one side of the operation lever (130) so that the operation lever (130) may rotate along the inner surface of the locking protrusion portion (113) and a locking tap (133) and a locking piece (135) are formed at one end and the other end of the curved portion (131) so as to be locked with the locking protrusion portion (113), and one end of the protruding piece (211) of the lower body (210) contacts the locking tap (133) or the locking piece (135), and the other end of the protruding piece (211) contacts the outer surface of the locking protrusion portion (113) to thus restrict rotation of the operation lever (130).

[5] The valve locking device according to any one of claims 1 to 4, wherein the nut engagement portion (150) comprises: a nut portion (151) around the inner circumferential surface of which a thread is formed and which makes the operation lever fixed to and coupled with the rotating shaft (120); a nut upper body portion (155) which is extended upwards from the nut portion (151), and which has an outer diameter smaller than that of the nut portion (151); and a locking groove (153) formed between the nut portion (151) and the nut upper body (155).

[6] The valve locking device according to claim 5, wherein the nut upper body (155) of the nut engagement portion (150) is gradually reduced in diameter upwards.

[7] The valve locking device according to claim 5, wherein the upper portion of the nut upper body (155) in the nut engagement portion (150) is sharply formed.

[8] The valve locking device according to claim 2 or 3, wherein a mount groove

(215) and an elastic accommodation groove (217) are formed on the upper surface of the lower body (210) in which the moving plate (221) is mounted in the mount groove (215) and the elastic portion (225) is accommodated in the elastic accommodation groove (217).