Description of the Background Art Generally, a LPG (Liquefied Petroleum Gas) is obtained by a refining of crude petroleum and has a major component of propane and butane. Propylene and butylen are added thereto and are pressurized for thereby fabricating LPG.

The LPG is lighter than water and heavier than air and is a flammable gas and has characteristics of no color, no smell and no taste. In addition, since the LPG is heavier than air, in the case that the LPG is leaked to the outside, it is not spread but gathered in a lower portion in the place in which the leakage occurred. Therefore, a certain explosion may occur due to static electricity or flame.

In the case that the volume of the cylinder filled with the LPG having an explosion danger is sharply increased due to the heating of the LPG due to a fire, etc. , a safety valve is operated for discharging the gas to the outside until the gas pressure is decreased to the standard pressure.

As shown in Figure 1, in the valve of the conventional gas cylinder

having the above-described problems, there is provided a valve body 10. The valve b ody 10 i ncludes a n engaging p art 11 formed i n a I ower p ortion of the same for a threading engagement, a connection part 12 formed in one side of the same so that a pressure controller is connected with a gas instrument such as a gas range or a boiler for supplying a gas having a constant pressure, and a safety valve 13 installed in the other side of the same for discharging the gas to the outside when the pressure of the gas of the gas cylinder exceeds the standard pressure. In addition, there is further provided a handle 20 rotatably installed in an upper side of the valve body 10. A disconnection member 30 is engaged to a lower side of the handle 20 for disconnecting the flow of the gas in such a manner that the disconnection member 30 ascends or descends when the handle 20 is rotated.

At this time, the inner side of the engaging part 11 communicates with the inner side of the connection part 12 by a through hole 14, and the disconnection member 30 closes the upper side of the through hole 14 for thereby controlling the flow of the gas.

In the conventional valve of the gas cylinder, when a user rotates the handle 20 in the counterclockwise direction in order to use the gas, the disconnection member 30 ascends, and the through hole 14 is opened, and the LPG of the cylinder flows to the pressure controller through the engaging part 11, the through hole 14 and the connection part 12, so that the gas is supplied to each gas instrument when the pressure controller is opened.

However, in the conventional valve of the gas cylinder, when a part of the gas is leaked to the outside in the case that the pressure controller is abnormally connected with the valve body or the pressure controller has a certain problem, there is not any way to detect the leaking gas and disconnect

the same. In this case, when the gas is discharged to the pressure controller by rotating the handle, a safety accident may occur due to the leakage of gas.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a pressure sensing type valve of a LPG cylinder capable of overcoming the problems encountered in the conventional art.

It is another object of the present invention to provide a pressure sensing type valve of a LPG cylinder capable of preventing a safety accident due to a gas leakage by automatically disconnecting a LPG discharged to a pressure controller in the case that a part of LPG is discharged to the outside when a pressure controller is abnormally connected with a valve body or a pressure controller has a certain problem.

To achieve the above problems, in a valve of a LPG cylinder including a valve body that has an engaging part engaged with a gas cylinder and formed in a lower side, and a connection part connected with a pressure controller in one side of the same, a handle rotatably installed on an upper side of the valve body, and a disconnection member engaged to a lower side of the handle for thereby closing an upper side of the through hole adapted to communicate an inner side of the engaging part and an inner side of the connection part, there is provided a pressure sensing type valve of a LPG cylinder, comprising a first space part formed in an inner lower side of the disconnection member wherein a lower side of the first space part is opened; a gas inlet hole formed in a lateral wall of the disconnection member for inputting gas into an inner upper most portion of the space part; a piston that is installed in the first space part and descends by a pressure of gas inputted through the gas inlet hole ; a closing

plate installed in a lower side of a piston rod formed in a lower side of the piston for closing the lower side of the through hole ; a transfer hole formed at a certain portion of the valve body for transferring a part of the gas inputted into the engaging part into the interior of the connection part; and a check valve that is installed in the transfer hole and operates by a pressurizing pin engaged at a front end of the pressure controller.

In addition, there are further provided a second space part that is formed in an inner upper side of the disconnection member and communicates with the first space part; a stem that is elastically installed in the second space part and descends when a certain force is applied thereto from the upper side for thereby pressurizing an upper side of the piston; and a safety pin that detachably passes through the elongated holes formed in an upper outer wall of the valve body and an upper outer wall of the disconnection member for thereby moving down the stem and maintaining the moved down state.

To achieve the above objects, in a valve of a LPG cylinder that includes a valve body having an engaging part engaged with a gas cylinder and formed in a lower side, a connection part formed in one side of the same and connected with a pressure controller, and a through hole formed between the engaging part and the connection part for communicating an inner side of the engaging part and an inner side of the connection part, and a handle rotatably installed in an upper side of the valve body, there is provided a pressure sensing type valve of a LPG cylinder, comprising a disconnection member that has a gas inlet hole formed in an outer wall of one side for inputting a gas inputted into the connection part into the inner side, and a space part into which the gas inputted through the gas inlet hole is filled, wherein the disconnection member moves up and down based on the rotation of the handle

for thereby opening and closing the u pper s ide of the through h ole ; a piston installed in the inner side of the disconnection member and having a hole formed in a horizontal direction for communicating the space part and the engaging part; a check valve installed in the inner side of the piston for opening and closing the hole ; a closing plate installed in a lower side of the piston for opening and closing the lower side of the through hole ; and a pressurizing rod installed between the handle and the check valve for starting operation of the check valve based on the rotation of the handle.

In the check valve, a pressurizing pin is installed in an upper side of the same, and a spring is engaged in the interior of the same for thereby closing the input of the gas, and in the above state, when the pressurizing pin is pressurized by the pressurizing rod, the compression gas inputted into the hole is discharged in the direction of the pressurizing pin.

The pressurizing rod includes a circular plate shaped driving threaded part installed in the side of the handle, and a driven threaded part installed in the side of the safety pin wherein an upper side of the same is formed in a circular plate shape, and a pressurizing rod is longitudinally extended in the side of the safety pin in a lower side of the same, and wherein the driving threaded part is rotatable in cooperation with the handle, and the driven threaded part is movable up and down, and a plurality of teeth each having a certain height H and a slanted surface L are formed in the lower s urface of t he c ircular p late o f t he d riving t hreaded part a nd t he upper surface of the circular plate of the driven threaded part in such a manner that the teeth correspond with each other, and when the handle is rotated, the driving threaded part is rotated together with the handle, and the driven threaded part is moved down by the height H of the teeth, so that the

pressurizing pin is pressurized by the pressurizing rod of the driven threaded part.

A circular rotation member is engaged to a lower side of the handle by a bolt, and a circular plate shaped groove is formed in a lower surface of the rotation member, and the driving threaded part is engaged in the groove, and when the handle is rotated, the driving threaded part is rotated in cooperation with the rotation of the handle.

A stem is installed in the upper and lower sides of the space part partitioned by the piston for thereby pressurizing the upper side of the piston, and a safety pin is detachably installed through the elongated holes formed in an outer wall of one side of the valve body and an outer wall of the other side of the disconnection member, and the step is downwardly supported by the safety pin so that the stem pressurizes the upper side of the piston until a nitride gas is discharged.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will become better understood with reference to the accompanying drawings which are given only by way of illustration and thus are not limitative of the present invention, wherein; Figure 1 is a cross sectional view illustrating a conventional valve of a gas cylinder ; Figure 2 is a cross sectional view illustrating a pressure sensing type valve of a LPG gas according to an embodiment of the present invention; Figure 3 is a cross sectional view illustrating a state that a safety pin of Figure 2 is separated according to the present invention; Figure 4 is a cross sectional view illustrating a state that a pressure

controller is connected with a connection part of Figure 2 according to the present invention; Figure 5 is a partially cut-away perspective view illustrating a disconnection member of Figures 2 and 3 according to the present invention; Figure 6 is a disassembled perspective view illustrating a disconnection member of Figures 2 and 3 ; Figure 7 is a cross sectional view illustrating a pressure sensing type valve of a LPG cylinder before a safety pin is separated according to another embodiment of the present invention; Figure 8 is a cross sectional view illustrating a state that a safety pin is separated according to another embodiment of the present invention; Figure 9 is a cross sectional view illustrating a state that a disconnection member closes a pressure sensing type valve of a LPG cylinder as a LPG is filled in the interior of a cylinder, and a handle is rotated in a. clockwise direction according to another embodiment of the present invention; Figure 10 is a cross sectional view illustrating a state that a disconnection member opens a pressure sensing type valve of a LPG cylinder as a LPG is filled in the interior of a cylinder, and a handle is rotated in a counterclockwise direction according to another embodiment of the present invention; Figure 11 is a disassembled view illustrating a valve of Figures 7 through 10 according to the present invention; Figure 12 is a partial cut-away perspective view illustrating a disconnection member of Figures 7 through 10 according to the present invention ; Figure 13 is a disassembled perspective view illustrating a

disconnection member of Figures 7 through 10 according to the present invention; Figure 14A is a cross sectional view illustrating a state before a threaded part is operated according to another embodiment of the present invention; and Figure 14B is a cross sectional view illustrating a state after a threaded part is operated according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Figure 2 is a cross sectional view illustrating a pressure sensing type valve of a LPG gas according to an embodiment of the present invention, Figure 3 is a cross sectional view illustrating a state that a safety pin of Figure 2 is separated according to the present invention, Figure 4 is a cross sectional view illustrating a state that a pressure controller is connected with a connection part of Figure 2 according to the present invention, Figure 5 is a partially cut-away perspective view illustrating a disconnection member of Figures 2 and 3 according to the present invention, and Figure 6 is a disassembled perspective view illustrating a disconnection member of Figures 2 and 3.

As shown therein, the pressure sensing type valve of a LPG cylinder according to an embodiment of the present invention includes a valve body 110 engaged to a gas cylinder 200, a handle 130 rotatably installed in an upper side of the valve body 110, and a disconnection member 40 installed in a lower side of the handle 130 for disconnecting the flow of gas.

The valve body 110 is engaged to an upper side of the gas cylinder 200.

An engaging part 111 threaded with the gas cylinder 200 is integrally formed in a lower side of the valve body 110. A connection part 112 connected with a

pressure controller 300 for supplying a gas of constant pressure to a certain gas instrument such as a gas range or boiler is installed in one side of the valve body 110. A safety valve 113 is installed in the other side of the same for discharging the LPG from the gas cylinder 200 to the outside in the case that the pressure of the gas in the gas cylinder 200 exceeds a certain pressure. The inner side of the engaging part 111 communicates with the inner side of the connection part 112 by a through hole 114.

In the preferred embodiment of the present invention, a transfer hole 115 is formed at a certain portion of the valve body 110 installed between the inner side of the engaging part 111 and the inner side of the connection part 112 for transferring a part of the gas inputted through the engaging part 111 to the connection part 112. A check valve 120 is installed in the transfer hole 115 and is operated by a pressurizing pin 301 installed at a front end of the pressure controller 300.

In addition, the check valve 120 is elastically installed in the transfer hole 115 by a spring 121. When an external force is not supplied, the circular lower part having a diameter smaller than the inner diameter of the transfer hole 115 closely contacts with a lower surface of a protrusion 116 protruded from an inner edge portion of the transfer hole 115. In the above state, when the upper side is pressurized by the pressurizing pin 301 of the pressure controller 300, the circular lower part is separated from the protrusion 116 and descends, so that the gas is transferred through a gap formed between the circular lower part and the inner surface of the transfer hole 115. At this time, the pressurizing pin 301 engaged to the front end of the pressure controller 300 is inserted into the transfer hole 115 when the pressure controller 300 is connected with the connection part 112 for thereby pressurizing the upper portion of the check

valve 120 and downwardly moving the same. In the above process, the gas filled in the gas cylinder 200 is transferred to the connection part 112 through the transfer hole 115 by the pressure itself.

Since the handle 130 is the same as the handle of the valve of the known gas cylinder, the description of the same is omitted.

The disconnection member 140 is engaged to a lower side of the handle 130 and is moved up and down during the rotation of the handle 130 for thereby closing the upper side of the through hole 114. A downwardly opened first space part 140a is formed in the inner lower side. A gas inlet hole 140b is formed in one side wall, so that the gas inputted into the connection part 112 is inputted into the inner upper most side of the first space part 140a. An upwardly opened second space part 140c is formed in the inner upper side and communicates with the first space part 140a. An O-ring 141 is engaged to the outer upper side for thereby achieving a closing operation.

Here, the piston 142 is installed in the first space part 140a wherein the piston 142 descends by the pressure of gas inputted through the gas input hole 140b. A closing p late 144 is installed in a lower side of a p iston rod 143 f or closing a lower side of the through hole 114.

In addition, a stem 145 is elastically installed in the second space part 140c by a spring 146 wherein the stem 145 descends during the discharge of nitride gas for thereby moving down the piston 142. The stem 145 descends by the safety pin 147 sequentially passing through the elongated holes 140d formed in the upper outer wall of the valve body 110 and the upper lateral wall of the disconnection member 140 during the initial discharge of nitride gas and maintains the moved-down state. Namely, as the stem 145 descends by the installation of the safety pin 147, the piston 142 and the piston rod 143 descend.

The c losing plate 144 e ngaged t o a n e nd of the piston rod 1 43 is separated from the lower side of the through hole 114, so that the lower side of the through hole 114 is opened. At this time, the safety pin 147 is closely contacted with the upper most end portion of the elongated hole 140d by an elastic force of the spring 146 and is fixed to the valve body 110, so that even when the disconnection member 140 is moved up by rotating the handle 130 in the counterclockwise direction, the safety pin 147 and the stem 145 maintain the stopped state. In addition, the disconnection member 140 is moved up until the safety pin 147 is closely contacted with the elongated hole 140d within a range of the elongated hole 140d.

Figure 7 is a cross sectional view illustrating a pressure sensing type valve of a LPG cylinder before a safety pin is separated according to another embodiment of the present invention, Figure 8 is a cross sectional view illustrating a state that a safety pin is separated according to another embodiment of the present invention, Figure 9 is a cross sectional view illustrating a state that a disconnection member closes a pressure sensing type valve o f a LPG c ylinder a s a L PG i s filled i n t he i nterior o f a c ylinder, and a handle is rotated in a clockwise direction according to another embodiment of the present invention, Figure 10 is a cross sectional view illustrating a state that a disconnection member opens a pressure sensing type valve of a LPG cylinder as a LPG is filled in the interior of a cylinder, and a handle is rotated in a counterclockwise direction according to another embodiment of the present invention, Figure 11 is a disassembled view illustrating a valve of Figures 7 through 10 according to the present invention, Figure 12 is a partial cut-away perspective view illustrating a disconnection member of Figures 7 through 10 according to the present invention, Figure 13 is a disassembled perspective

view illustrating a disconnection member of Figures 7 through 10 according to the present invention, Figure 14A is a cross sectional view illustrating a state before a threaded part is operated according to another embodiment of the present invention, and Figure 14B is a cross sectional view illustrating a state after a threaded part is operated according to another embodiment of the present invention.

As shown therein, in another embodiment of the present invention, the transfer hole 115 is not formed. In the earlier embodiment of the present invention, since there is a certain case that the gas is leaked through the transfer hole 115 without flowing through the closing plate 144, the transfer hole 115 is not formed. Therefore, in another embodiment of the present invention, the check valve is installed in a certain space, not in the transfer hole 115.

In another embodiment of the present invention, as shown in Figure 7, in a pressure sensing valve of a LPG cylinder 400, there is provided a valve body 110 in which an engaging part 111 is formed in a lower side and is threaded with a gas cylinder 200. In addition, a connection part 112 is formed in one side. A pressure controller 300 is installed in a gas instrument for supplying a constant pressure gas/A safety valve 113 is installed in the other side for discharging the LPG in the gas cylinder 200 to the outside when the pressure of the gas in the gas cylinder 200 exceeds a certain pressure. T here is further provided a handle 130 rotatably installed in an upper side of the valve body 110.

In addition, a disconnection member 410 is installed in a lower side of the handle 130 for thereby disconnecting the flow of the gas.

In addition, as shown in Figure 11, the inner side of the engaging part 111 communicates with the inner side of the connection part 112 by the through hole 114. The through hole 114 is selectively opened and closed in such a

manner that the disconnection member 410 slides up and down by the rotation of the handle 130.

Since the handle 130 is the same as the handle of the valve of the conventional gas cylinder, the description of the same will be omitted. In another embodiment of the present invention, a threaded part 470 is further formed in a lower side of the handle 130.

The disconnection member 410 is engaged to a lower side of the handle 130 and is moved up and down during the rotation of the handle 130, so that the upper side of the through hole 114 is opened and closed. The upper disconnection member 410a and the lower disconnection member 410 are separately formed and threaded each other, so that a hollow cylinder shape is formed.

A gas inlet hole 412 is formed in an outer wall of one side of the disconnection member 410 so that the g as i nputted from the connection part 112 is inputted in the direction of the inner side of the disconnection member 410. A space part 414 is formed in an inner upper side of the disconnection member 410, so that the gas is filled thereinto through the gas inlet hole 410. A piston 420 is installed in an inner upper side of the disconnection member 410 wherein the piston 420 moves up and down in the interior of the disconnection member and partitions the space part 414 and the through hole 114. An O-ring 422 is installed in an outer side of the piston 420 for thereby achieving a closing operation.

A hole 424 is longitudinally formed in a center lower side of the piston 420 in a horizontal direction wherein the hole 424 communicates the engaging part 111 and the space part 414. A check valve 430 is installed in an inner side of the center upper portion of the piston 420 for thereby opening and closing the

engaging part 111 and the space part 414.

In the check valve 430, a pressurizing pin 432 is installed in an upper side of the same, and the spring 434 is installed in the interior. The check valve 430 closes the input and output of the gas. When the pressurizing pin 432 of the upper side is downwardly pressurized, the compression gas of the lower side inputted through the hole 424 is discharged to the upward direction through the outlet of the interior.

A closing plate 440 is installed in a lower side of the piston 420 for thereby opening and closing the through hole 114 and the engaging part 111. A closing rubber 442 is engaged in an upper side of the closing plate 440 for closing the gas so that the gas is not inputted into the through hole 114 during the closing of the handle 130.

In the space part 414, a stem 450 is installed in an upper side of the piston 420 for downwardly supporting the piston 420 when nitride gas is discharge at the initial stage. The stem 450 is downwardly supported by the safety pin 460 sequentially passing through the elongated holes 416 formed in the upper outer wall of the valve body 110 and the upper side wall of the disconnection member 140 during the initial discharge of the nitride gas and maintains the downwardly moved state.

Namely, as the stem 450 descends based on the installation of the safety pin 460, the piston 420 descends. The closing plate 440 engaged at an end of the piston 420 is separated from the lower side of the through hole 114, so that the lower side of the through hole 114 is opened. At this time, since the safety pin 460 downwardly supports the piston 420, even when the disconnection member 410 is upwardly moved by rotating the handle 130 in the counterclockwise direction, the safety pin 460 and the stem 450 maintain a

stopped state. The disconnection member 410 is moved up until the safety pin 460 is closely contacted with the lower side of the elongated hole 416 within a range of the elongated hole 416.

A handle 462 is installed in an outer end portion of the safety pin 460.

As shown in Figure 8, the safety pin 460 is removed from the valve body 110 by pulling the handle 462 after the nitride gas is discharged.

In addition, a driving threaded part 470 is installed in a lower center of the handle 130, and a driven threaded part 480 is installed in a center inner side of the disconnection member 410. In more detail, a circular rotation member 130 is engaged to a lower side of the handle 130 by a bolt 130", and a circular groove is formed in a lower surface of the rotation member 130'1, and the driving threaded part 470 is fixed to the groove.

Namely, the driving threaded part 470 is formed in a circular plate shape.

As shown in Figure 14A, a plurality of teeth 472 each having a certain height H and a slanted surface L are formed in a lower surface of the circular plate shape.

The upper side of the driven threaded part 480 is formed in a circular plate shape. A plurality of teeth 482 corresponding to the teeth 472 of the driving threaded part 470 are formed in the upper surface of the circular plate shape. A pressurizing rod 484 is longitudinally extended from the lower side of the same in the direction of the pressurizing pin 432 of the check valve 430.

In addition, the driving teeth 470 are designed to rotate together with the handle 130. As shown in Figure 14B, the driven teeth 480 do not rotate, but is designed to move only in the upward and downward directions.

Therefore, when the handle 130 is rotated, the driving threaded part 470 is rotated together with the handle 130. At this time, the teeth 482 of the driven threaded part 480 engaged with the teeth 472 of the driving threaded part 470

should be rotated together, but the driven teeth 480 are designed to move only in the upward and downward directions. Therefore, as shown in Figure 14A, the driven threaded part 480 is moved down by the distance corresponding to the height H of the teeth of the driving threaded part 470.

In another embodiment of the present invention, when the driven threaded part 480 is moved down, the pressurizing rod 484 of the driven threaded part 480 pressurizes the pressurizing pin 432, so that the outlet of the check valve 430 is opened. Therefore, it is not needed to form the transfer hole in this embodiment of the present invention.

The operation of the pressure sensing type valve of a LPG cylinder according to another embodiment of the present invention will be described.

First, a certain amount of nitride gas or compressed air is filled in the gas cylinder 200 having the pressure sensing type valve of the LPG cylinder 100 before the LPG is filled into the gas cylinder 200, so that it is checked whether gas is leaked from the gas cylinder 200 during the closing test.

The LPG is filled into the gas cylinder 200 in a state that the nitride gas is filled after the closing test is finished in such a manner that the nitride gas is filled into the gas cylinder 200, so that a relatively lighter nitride gas is positioned i n t he u pper s ide o f t he g as c ylinder 200, and a r elatively h eavier LPG is positioned in the lower side of the gas cylinder 200.

When filling the LPG, since the LPG and nitride gas coexist in the gas cylinder 200, so that the LPG supplier should discharge the nitride gas to the outside before the gas cylinder 200 is delivered to customers.

The disconnection member 140 descends and becomes a state that the upper side of the through hole 114 is closed before the nitride gas is discharged.

The safety pin 460 passes through the valve body 110 and the disconnection

member 41 and allows the stem 145 to descend, so that the piston 142 and the piston rod 143 descend. The closing plate 144 engaged to the end of the piston rod 143 descends and is separated from the lower side of the through hole 114.

Therefore, when the handle 130 is rotated in the counterclockwise direction for discharging the nitride gas, the stem 145 and the piston 142 are prevented from ascending by the safety pin 147. The disconnection member 140 ascends within the range of the elongated hole 140d and is separated from the upper side of the through hole 114, so that the through hole 114 is opened, whereby the nitride gas filled in the gas cylinder 200 is discharged to the outside through the through hole 114.

When the gas supplier rotates the handle 130 in the clockwise direction after the nitride gas is discharged, the disconnection member 140 descends, and the upper side of the through hole 114 is closed, so that the gas in the gas cylinder 200 is not discharged to the outside.

After the nitride gas filled in the gas cylinder 200 is fully discharged, when the safety pin 147 is separated, the stem 145 is returned to its original state by an elastic force of the spring 146, and the pressurizing force applied to the piston 142 is released, so that the piston 142, the piston rod 143 and the closing plate 144 ascend together by the pressure of the gas and are closely contacted with the lower side of the through hole 114, for thereby closing the lower side of the through hole 114.

The nitride gas is fully discharged, and the through hole 114 that is a gas discharge path is fully closed. The gas cylinder 200 is supplied to the customers. In the above state, when the user connects the pressure controller 300 connected with the end of a gas hose with the connection part 112 of the valve body 110, as shown in Figure 4, the pressurizing pin 301 engaged at the

front end of the pressure controller 300 pressurizes the upper side of the check valve 120 installed in the transfer hole 115, so that the transfer hole 115 is opened, and a part of the gas filled in the gas cylinder 200 is transferred to the connection part 112 through the transfer hole 115, and the gas transferred into the connection part 112 is inputted into the inner upper most portion of the first space part 140a through the gas inlet hole 140b formed in the lateral wall of the disconnection member 140 through a gap formed between the disconnection member 140 and the valve body 110. Therefore, the piston 142 in the first space part 140a descends by the pressure of the gas inputted, and the piston rod 143 and the closing plate 144 descend, and the closing plate 144 is separated from the lower side of the through hole 114.

After the closing plate 144 is separated from the lower side of the through hole 114, when the handle 130 is rotated in the counterclockwise direction, the disconnection member 140 ascends and is separated from the upper side of the through hole 114, so that the through hole 114 is fully opened.

When the user opens the valve of the pressure controller 300, the gas filled in the gas cylinder 200 is transferred to the gas instrument through the valve body 110 and the pressure controller 300.

When the pressure controller 300 is connected to the connection part 112 of the valve body 110, in the case that a certain problem occurs in the connection or the pressure controller 300 has a problem, the gas transferred to the connection member 112 through the transfer hole 115 is not inputted into the inner side of the first space part 140a of the disconnection member 140, but is discharged to the outside through a defective portion of the pressure controller 300. At this time, the piston 142 maintains the stopped state. The closing plate 144 is closely contacted with the lower side of the through hole 114, so that the

lower side of the through hole 114 is closed.

Therefore, in this case, even when the user rotates the handle 130 in the counterclockwise direction and opens the pressure controller 300, the gas in the gas cylinder 200 is disconnected and is not discharged to the outside.

Even though the handle 130 is rotated, and the pressure controller 300 is opened, when the LPG is not discharged, the user separates the pressure controller 300 and normally connects the same. When it is damaged, it is simply exchanged.

The operation of the pressure sensing type valve of a LPG cylinder according to another embodiment of the present invention will be described.

In this embodiment of the present invention, the nitride gas or compressed air is previously filled in the gas cylinder 200 having the pressure sensing type valve 100 of the LPG cylinder according to the present invention before the LPG is filled, so that it is checked whether the gas is leaked from the gas cylinder 200. Namely, the closing test is performed in the same manner as the earlier embodiment of the present invention. In this embodiment of the present invention, the LPG is charged into the gas cylinder 200 after the nitride gas or compressed air are fully discharged after the closing test is performed, and the LPG filled gas cylinder is used by the user at home, etc. The above procedure will be described.

The disconnection member 410 descends before the nitride gas is discharged, and the upper side of the through hole 114 is closed. The safety pin 460 passes through the valve body 110 and the elongated hole 416 of the disconnection member 410 and allows the stem 450 to descend. The piston 420 descends. The closing plate 440 engaged to an end portion of the piston 420 descends and is separated from the lower side of the through hole 114.

When the handle 130 is rotated in the counterclockwise direction in order to discharge the nitride gas, as shown in Figure 7, the stem 450 and the piston 420 are prevented from ascending. The disconnection member 410 ascends within the range of the elongated hole 416 and is separated from the upper side of the through hole 114, and the through hole 114 is opened, so that the nitride gas filled in the gas cylinder 200 is discharged to the outside through the through hole 114.

Therefore, in the present invention, the nitride gas is safely discharged for a short time, and the work process is decreased. The process for quickly discharging the nitride gas in another embodiment of the present invention is the same as the earlier embodiment of the present invention.

After the nitride gas is discharged, as shown in Figure 8, the gas supplier pulls the handle 462 and removes the safety pin 460 from the valve body 110. In addition, when the gas supplier injects the gas through the connection part 112, the LPG is filled into the gas cylinder 200.

At this time, when the LPG is filled in the gas cylinder 200, since the gas pressure upwardly pressurizes the closing plate, the c losing plate 440 is upwardly moved without additionally using the elastic unit and is closely contacted with the lower side of the through hole 114, so that the lower side of the through hole 114 is closed.

The gas cylinder 200 is delivered from the gas supplier to a gas user.

The gas user connects the pressure controller 300 connected to an end of the gas hose to the connection part 112 of the valve body 110 and rotates the handle 130 in the counterclockwise direction. As shown in Figure 9, the rotation member 130'engaged to the handle 130 by the bolt 130"is rotated. The driving threaded part 470 is rotated together.

As this time, as shown in Figure 14a, the teeth 472 of the driving threaded part 470 are engaged with the teeth 482 of the driven threaded part 480. When the driving threaded part 470 is rotated, the driven treaded part 480 is designed to be moved up. As shown in Figure 14B, the driven threaded part 480 is moved by the distance by the height H of the teeth 482.

Therefore, the pressurizing rod 484 of the driven threaded part 480 moved down pressurizes the pressurizing pin 432 of the check valve 430, and the check valve 430 is opened, and the compression gas of the gas cylinder 200 is inputted into the upper space part 414 through the hole 424.

The compression gas inputted into the space part 414 pressurizes the upper side of the piston 420 and allows the disconnection member 410 engaged with the piston 420 to move down, so that the closing plate 440 is separated from the lower side of the through hole 114, and the lower side of the through hole 114 is opened.

When the handle 1 30 is rotated in the counterclockwise direction, as shown in Figure 10, the disconnection member 410 ascends and is separated from the upper side of the through hole 114, so that the through hole 114 is fully opened. Therefore, when the user opens the valve of the pressure controller 300, the gas filled in the gas cylinder 200 is transferred to the gas instrument through the valve body 110 and the pressure controller 300.

In addition, the driving threaded part 470 is driven by the rotation of the handle 130, and the pressurizing pin 432 starts operating by the pressurizing rod 484 of the driven threaded part 480. In this state, even when the pressurizing pin 432 of the check valve 430 is not pressurized, a part of the gas from the opened closing plate 440 is inputted into the gas inlet hole 412 through the through hole 114 and the outer side of the disconnection member 410. The

thusly inputted gas is always filled in the space part 414. Therefore, the closing plate 440 maintains in the opened state.

On the contrary, the pressure controller 300 may be opened on purpose for a certain purpose, for example, a crime, etc. At this time, in a state that the pressure controller 300 is not normally installed in the connection part 112, when the handle 130 is rotated in the counterclockwise direction, the gas from the closing plate 440 is not inputted into the space part 414 through the gas inlet hole 412. Therefore, since it is impossible to continuously maintain the closing plate 440 in the opened state, it is possible to prevent a certain accident due to the leakage of gas.

As described above, in the pressure sensing type valve of a LPG cylinder according to the present invention, it is possible to prevent a safety accident due to a gas leakage by automatically disconnecting a LPG discharged to a pressure controller in the case that a part of LPG is discharged to the outside when a pressure controller is abnormally connected with a valve body or a pressure controller has a certain problem.

As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described examples are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended c laims, a nd t herefore a ll c hanges a nd m odifications t hat f all w ithin the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.