WO2005111962A1 - Gas leakage prevention system and method of using the same - Google Patents
Gas leakage prevention system and method of using the same Download PDFInfo
- Publication number
- WO2005111962A1 WO2005111962A1 PCT/KR2005/000931 KR2005000931W WO2005111962A1 WO 2005111962 A1 WO2005111962 A1 WO 2005111962A1 KR 2005000931 W KR2005000931 W KR 2005000931W WO 2005111962 A1 WO2005111962 A1 WO 2005111962A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- gas
- intermediate valve
- pressure
- sensor
- appliance
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
- G08B21/02—Alarms for ensuring the safety of persons
- G08B21/12—Alarms for ensuring the safety of persons responsive to undesired emission of substances, e.g. pollution alarms
- G08B21/16—Combustible gas alarms
Abstract
A gas leakage prevention system comprises: a first judging unit for judging whether a gas appliance is ignited or not; a second judging unit for judging whether an intermediate valve installed in a passage of gas flowing into the gas appliance is open or closed; and an intermediate valve control unit for closing the intermediate valve when the first judging unit judges the gas appliance is not ignited and the second judging that unit judges the intermediate valve is open. Detecting sensors are installed in piping between the gas appliance and the intermediate valve and in piping between the intermediate valve and an external gas supply source. It is possible to provide the convenience of automatic opening and closure according to whether the gas appliance is ignited or not, and thus to reduce the risk of an accident caused by gas leakage, because the opening and closing operation is conducted.
Description
GAS LEAKAGE PREVENTION SYSTEM AND METHOD OF USING THE SAME
BACKGROUND OF THE INVENTION
1. Field of the Invention The present invention relates to a gas leakage prevention system and a method of using the same, and more particularly, to a gas leakage prevention system which is able to detect leaking gas and take proper measures in the event of gas leakage caused by failure of a gas range or an intermediate valve as well as by a user's carelessness, and a method of using the same.
2. Description of the Background Art Generally, kitchens and heating apparatus in houses, restaurants, etc., use gas appliances such as gas ranges, gas ovens, gas boilers, etc. which use gases such as LPG, LNG, etc. as fuel. Such a gas appliance is connected to an outdoor gas tank or a gas supply of a gas provider by piping to supply gas, and an intermediate valve, is installed between the gas appliance and the outdoor gas tank or between the gas appliance and the gas supply of a gas provider to thus allow a user to regulate or shot off a gas supply. When it is desired to cook food or heat a room using a gas appliance, the user opens an intermediate valve to supply gas to the gas appliance and ignites the supplied gas using an ignition device installed in the gas appliance. After the use of the gas appliance is over, first the ignition device installed in the gas appliance is closed to extinguish the gas and then the intermediate valve is closed to shut off the gas supply. That is, because gas leakage from the gas
appliance may cause a hazard such as a risk of explosion or the like, safety is promoted by means of the dual structure comprising the ignition device installed in the gas appliance and the intermediate valve installed in the gas piping. However, even in the case of minimizing the risk of gas leakage by the aforementioned intermediate valve, due to the trouble of having to open and close the intermediate valve each time when using the gas appliance, it is often the case that the user regulates the gas supply only by the ignition device and keeps the intermediate valve open all the time. Further, when the gas appliance or intermediate valve is old, there is the possibility of a small amount of gas leaking, and a risk of the leaked gas accumulating on the floor of a kitchen or boiler room and exploding.
SUMMARY OF THE INVENTION
The present invention has been found to overcome the above problems, and it is an object of the present invention to provide a gas leakage prevention system which eliminates the user's need to open and close an ignition device and an intermediate valve every time gas appliance is used and reduces the risk of fire by sensing leaked gas, and a method of using the same. To achieve the above object, there is provided a gas leakage prevention system according to the present invention, comprising: a first judging unit for judging whether a gas range is ignited or not; a second judging unit for judging whether an intermediate valve installed in a passage of gas flowing into the gas range is open or closed; and an intermediate valve control unit for closing the intermediate valve when the first judging unit judges that the gas range is not ignited and the second judging unit determines that the intermediate valve is
opened. In gas leakage prevention system, the intermediate valve control unit opens the intermediate valve when the first judging unit judges that the gas range is ignited and the second judging unit determines that the intermediate valve to be closed. Preferably, the gas leakage prevention system further comprises a flow measurement sensor installed in a passage of gas between the gas range and the intermediate valve for measuring a flow rate of gas flowing into the gas range, wherein the intermediate valve control unit closes the intermediate valve when the first judging unit judges that the gas range is not ignited and the flow measurement sensor detects gas flowing into the gas range. Preferably, the gas leakage prevention system further comprises an alarm device for generating a given alarm signal when the flow measurement sensor detects gas flowing into the gas range, when the first judging unit determines that the gas range is not ignited and the second judging unit determines that the intermediate valve is closed. At this time, it is preferable that the flow measurement sensor is a heat type air flow measurement sensor embodied in a MEMS (micro electro mechanical system). Preferably, the gas leakage prevention system further comprises: a receiving unit connected to alarm devices respectively installed in a plurality of houses for receiving an alarm signal sent out from at least one alarm device; and a display for displaying the location of a corresponding house when a alarm signal is received by the receiving unit. According to another preferred embodiment of the present invention, a first detecting sensor is installed in a passage of gas between the intermediate
valve and the gas appliance and a second detecting sensor is installed in a passage of gas between the intermediate valve and a given gas supply source. The first judging unit and second judging unit judge whether the gas appliance is ignited or not and whether the intermediate valve is opened or not on the basis of detection results of the first detecting sensor and the second detecting sensor, respectively, or on the basis of all the detection results of the first detecting sensor and the second detecting sensor. At this time, each of the first detecting sensor and the second detecting sensor includes either a flow measurement sensor, a pressure sensor, or a line leak detector. The first judging unit judges whether the gas appliance is ignited or not on the basis of a pressure measurement value, a pressure change or a flow rate change detected by the first detecting sensor, and the second judging unit judges whether the intermediate valve is opened or closed on the basis of a pressure measurement value, a pressure change or a flow rate change detected by the first detecting sensor and/or the second detecting sensor. When a flow rate higher than a predetermined critical value is detected by the flow measurement sensor or a pressure of less than a predetermined critical value is detected by the pressure sensor, the intermediate valve control unit closes the intermediate valve. Furthermore, it is also possible to close intermediate valve when an external sensor for sensing gas is installed at a predetermined position around the gas appliance and a gas leakage sensing signal is transferred from the external sensor. Preferably, in the gas leakage prevention system according to the embodiment of the present invention, the first detecting sensor and the second detecting sensor are configured as pressure sensors or differential pressure
sensors to detect pressures in gas inlet side and gas outlet side of the intermediate valve, respectively, and the intermediate valve control unit compares the pressures detected in the gas inlet side and gas outlet side of the intermediate valve with each other, and controls the intermediate valve such that, when the pressure of the gas outlet side is lower than the pressure of the gas inlet side, the intermediate valve is opened, and when a pressure difference between the gas inlet side and the gas outlet side is lower than a minimum pressure difference to ignite the gas appliance, the intermediate valve is closed. At this time, the first detecting sensor and the second detecting sensor may be respectively connected to opposite sides of the intermediate valve which is configured as a unit having the gas inlet side and the gas outlet side with different diameters. Preferably, in the gas leakage prevention system, the first detecting sensor comprises a differential pressure sensor to measure a pressure change in the gas outlet side of the intermediate valve, wherein the intermediate valve control unit controls the intermediate valve such that, when a pressure measured by the differential pressure sensor is lower than a reference pressure for the gas inlet side, the intermediate valve is opened, and when a difference between the pressure measured by the differential pressure sensor and the reference pressure for the gas inlet side is lower than a minimum pressure difference to ignite the gas appliance, the intermediate valve is closed. When the opening and closing of the intermediate valve is controlled through the above-mentioned method, the minimum pressure difference and the pressure difference between the gas inlet side and the gas outlet side may vary due to a change in the inlet gas pressure caused by a mechanical limit, so that the pressure difference between the gas inlet side and the gas outlet side may be reduced lower than the
minimum pressure difference and opposed to the method of closing the intermediate valve. In the above state, a pressure regulator or a pressure regulation tank to regulate the pressure in the gas inlet side of the intermediate valve and make the pressure in the gas inlet side constant is preferably installed in a passage of gas between the intermediate valve and a given gas supply source. Preferably, in the gas leakage prevention system, the first detecting sensor comprises a flow measurement sensor to measure a flow rate of gas, and the intermediate valve control unit controls the intermediate valve such that, when the flow rate of gas measured by the flow measurement sensor is higher than a minimum flow rate of gas to ignite the gas appliance, the intermediate valve, is opened, and, when the flow rate of gas measured by the flow measurement sensor is equal to or lower than the minimum flow rate of gas to ignite the gas appliance, the intermediate valve is closed. Furthermore, an electric motor-operated lever device for electrically opening and closing of the intermediate valve can be installed on the intermediate valve. The intermediate valve control unit opens and closes the intermediate valve by driving the electric motor-operated lever device. The present invention is also applicable to a gas appliance having a conventional manual intermediate valve. Here, the electric motor-operated lever device comprises a main body installed on the intermediate valve, a lever installed on the main body and coupled to the intermediate valve, a motor for driving the intermediate valve coupled to the lever by driving the lever and a display unit provided on the main body for displaying whether the intermediate valve is open or closed. A gas leakage prevention method using the gas leakage prevention
system according to the present invention comprises the steps of: (a) determining whether a gas range is ignited or not; (b) determining whether an intermediate valve installed in a supply passage of gas inflowing into the gas range is open or closed; and (c) closing the intermediate valve when the gas range is determined not to be ignited in the step (a) and the intermediate valve is determined to be opened in the step (b). Preferably, the gas leakage prevention method further comprises the steps of: (d) measuring the flow rate of gas flowing into the appliance from the supply passage between the gas range and the intermediate valve; and (e) closing the intermediate valve when the gas range is determined not to be ignited in the step (a) and gas is determined to be flowing into the gas range in the step (d). Preferably, the gas leakage prevention method further comprises the step of: (f) generating a given alarm signal when the gas range is judged not to be ignited in the step (a) and gas is determined to be flowing into the gas range in the step (d). Preferably, the gas leakage prevention method further comprises the steps of: (g) receiving the alarm signal sent out from at least one of the alarm devices respectively installed in a plurality of houses; and (h) displaying the location of a corresponding house when the alarm signal is received in the step
(g). Meanwhile, whether the gas appliance is ignited or not in the step (a) is determined on the basis of a pressure measurement value, a pressure change or a flow rate change detected by the first detecting sensor and/or the second detecting sensor, and whether the intermediate valve is opened or closed in the step (b) is determined on the basis of a pressure measurement value, a pressure
change or a flow rate change detected by the first detecting sensor and/or the second detecting sensor. According to a preferred embodiment of the present invention, the gas leakage prevention method further comprises the steps of: (i) determined whether the flow rate in the gas supply passage between the intermediate valve and the gas appliance is more than a predetermined critical flow rate or the pressure therein is less than a predetermined critical pressure; and (j) closing the intermediate valve when the flow rate is determined to be more than a predetermined critical flow rate or the pressure is determined to be less than a predetermined critical pressure. According to another preferred embodiment of the present invention, the gas leakage prevention method further comprises the step of: (k) determined whether gas is detected or not at a predetermined position around the gas appliance; and (I) closing the intermediate valve to be closed when gas is detected in the step (k). Consequently, the gas leakage prevention system according to the present invention is able to prevent an accident by detecting leaking gas and . taking proper measures in the event of gas leakage caused by failure of a gas range or an intermediate valve as well as by a user not closing the valve of the gas range or the intermediate valve.
BRIEF DESCRIPTION OF THE DRAWINGS .
Fig. 1 is a block diagram schematically illustrating an embodiment of a gas leakage prevention system according to the present invention; Fig. 2a is a plan view showing one example of a heat type air flow
measurement sensor used in the gas leakage prevention system of Fig. 1 , and Fig. 2b is a sectional view of the heat type air flow measurement sensor taken along the line A-A of Fig. 2a; Figs. 3a to 3c are a block diagram and views schematically illustrating another embodiment of the gas leakage prevention system according to the present invention; Fig. 4 is a block diagram schematically illustrating yet another embodiment of the gas leakage prevention system according to the present invention; Fig. 5 is a view showing one example of a display displayed on a central management system of Fig. 4; Fig. 6 is a flow chart showing a gas leakage prevention method using the gas leakage prevention system of Fig. 4; Figs. 7a and 7b are block diagrams illustrating further embodiments of the gas leakage prevention system according to the present invention; Figs. 8 to 10 are views illustrating a modified example of the present invention, in which a motor for opening and closing a conventional intermediate valve is installed on the intermediate valve.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Hereinafter, the operation of a gas leakage prevention system according to the present invention will be described in detail with reference to the accompanying drawings. Fig. 1 is a block diagram schematically illustrating an embodiment of. a gas leakage prevention system according to the present invention. Referring to
Fig. 1 , the gas leakage prevention system 100 according to the first embodiment has a gas range 10, an intermediate valve 20, a first judging unit 30, a second judging unit 40, an intermediate valve control unit 50 and an alarm device 70. In another embodiment according to the present invention a flow measurement sensor 60 may be added to the above-mentioned construction of the gas leakage prevention system. The first judging unit 30 determined whether the gas range 10 is ignited or not. Generally, a gas range 10 for home use has a matchstick sized fire extinguishing safety device attached beside a nozzle hole that for lets gas out. This fire extinguishing safety device senses heat upon normal ignition and opens a solenoid valve (not shown) housed in the gas range 10. It is preferable that the first judging unit 30 determine whether the solenoid valve is open or not using a general fire extinguishing safety device and determined whether the gas range 10 is ignited or not based on a temperature sensed by the fire extinguishing safety device. The second judging unit 40 determined whether the intermediate valve 20 installed at the gas piping connected to the gas range 10 is opened or closed., In the present invention, the intermediate valve 20 may be selected from a variety of valves capable of controlling the pathway of gas, such as solenoid valves and ball valves, rather than conventional simple fuse cock valves. Furthermore, the means for controlling the intermediate valve 20 may be selected from a variety of valve control instruments, such as DC motors and step motors having torques capable of controlling the intermediate valve. Preferably, the intermediate valve 20 is embodied in a solenoid valve so as to conduct on/off operation according to an electric signal received from the intermediate valve control unit 50. When the first judging unit 30 determined the gas range 10 not to be
ignited and the second judging unit 40 determined the intermediate valve 20 to be open, the intermediate valve control unit 50 closes over the intermediate valve 20 to shut off the gas being supplied to the gas range 10. When the first judging unit 30 determined that the gas range is ignited and the second judging unit 40 determined that the intermediate valve 20 is closed, it is preferred that the intermediate valve control unit 50 open the intermediate valve 20 to supply gas to the gas range 10. In this case, when the ignition device of the gas range 10 is open, flames for igniting gas are generated in a given cycle and the temperature of the fire extinguishing safety device rises due to the generated frames. When the temperature of the fire extinguishing safety device rises more than a predetermined value, a solenoid valve (not shown; hereinafter, referred to as an 'appliance valve' to be distinguishable from the solenoid valve used as the intermediate valve). By using this principle, it is preferable that the intermediate valve control unit 50 opens the intermediate valve the moment that the temperature of the fire extinguishing device has rises more than a predetermined value or the appliance valve is opened. By this method, the intermediate valve control unit 50 is able to prevent gas leakage by automatically opening/closing the intermediate valve 20 according to whether the gas range 10 is used or not even though the user does not open/close the intermediate valve whenever using the gas range 10. The flow measurement sensor 60 included in the gas leakage prevention system 100 of this invention is installed in the piping between the gas range 10 and the intermediate valve 20 and measures the flow rate of gas flowing into the gas range 10. In this case, the flow measurement sensor 60 is preferably a heat type air flow measurement sensor embodied in an MEMS (micro electro mechanical system) of 4 mm width X6 umι length.
However, the equipment referred to as a 'flow measurement sensor' in the present invention is not limited to a heat type air flow measurement sensor, but may include a wide variety of equipment generally called 'flow meters' as well as all kinds of sensors for measuring flow rate. It should be interpreted that the aforesaid examples of equipment for flow measurement do not limit the scope of the invention and the flow measurement sensor described with reference to Figs. 2a and 2b is just for illustration of a preferred embodiment of the present invention. Fig. 2a is a view showing one example of a heat type air flow measurement sensor used in the gas leakage prevention system 100 of Fig. 1. Fig. 2b is a sectional view of the heat type air flow measurement sensor of Fig. 2a taken along the line A-A. Referring to Figs. 2a and 2b, the heat type air flow measurement sensor 60 comprises a semiconductor substrate 61 of silicon or the like, an electric insulating film 69a constituting a barrier membrane, an upstream heating resistor 62a and a downstream heating resistor 62b formed on the electric insulating film 69a, a temperature measurement resistor 63 to detect a temperature of the heating resistors 62a and 62b, an air temperature measurement resistor 64 formed at the front end of the substrate 61 to detect an air temperature, terminal electrodes 68a, a68b, 68c, 68d, 68e, 68f and 68g to pass a signal from the heat type air flow measurement sensor 60 to an external circuit, wiring connecting units 67a, 67b, 67c, 67d, 67e, 67f and 67g to connect the resistors 62a, 62b, 63 and 64 and the terminal electrodes 68a, 68b, 68c, 68d, 68e, 68f and 68g and an electric insulating film 69b to protect the resistors 62a, 62b, 63 and 64. Here, the resistors 62a, 62b, 63 and 64 are made of a silicon (Si) semiconductor thin film doped with impurities and formed by heavy doping so that the resistivity of the
silicon semiconductor thin film is less than 8x 10"4Ω cτn. The operating principle of the heat type air flow measurement sensor 60 used in the gas leakage prevention system 100 according to the present invention is as follows. A pair of upstream and downstream heating resistors 62a and 62b is electrically and directly connected. A junction (center tap) D is connected to the terminal electrode 68 by an outgoing electrode 671 When a heating (indirect heat) current flows through the pair of heating resistors 62a and 63b formed on the above-said insulating film 69a thermally separated by a cavity 66, the temperature of the temperature measurement resistor 63 detecting the temperature of the heating resistors 62a and 62b increases by a predetermined value over the temperature of the air temperature measurement resistor 64 showing the air temperature. The direction of air flow is detected by comparing the temperatures of the heating resistors 62a and 62b with that of the temperature measurement resistor 63. That is, the heating resistors 62a and 62b are the same temperature as the temperature measurement resistor 63 when there is no air flow and do not show any temperature gap. Meanwhile, the heating resistor 62a arranged in the upstream side of the direction of air flow is subject to a bigger cooling effect due to air flow than is the heating resistor 62b arranged in the a downstream direction. Further, since the heating resistors 62a and 62b are serially connected and the same heating current is applied thereto so as to have the same heat production, the temperature of the upstream heating resistor 62a is lower than the temperature of the downstream heating resistor 62b. Meanwhile, when air flows becomes in the opposite direction (reverse direction) from the direction shown, the temperature of the downstream heating resistor 62b becomes lower than the
temperature of the upstream heating resistor 62a. Accordingly, it is possible to detect the direction of air flow by comparing the temperatures (resistance values) of the heating resistors 62a and 62b. Further, because the temperature measurement resistor 63 is made to have a higher temperature than the air temperature measurement resistor 64 by a predetermined value, the measurement of air flow is carried out based on a heating (indirect heat) current value applied to the heating resistors 62a and 62b. By this method, detecting an air flow direction and of an air flow rate is possible. Further, since such a heat type air flow measurement sensor 60 embodied in a MEMS is able to sense even a minute quantity of air flow, it is applied to the gas leakage prevention system 100 of this invention and plays the role of sensing a low level of gas leakage. When the gas leakage prevention system 100 according to the present invention has another flow measurement sensor 60, it is preferable that, when the first judging unit 30 determined that the gas range 10 is not ignited, and the flow measurement sensor 60 detects gas flowing into the gas range 10, the intermediate valve control unit 50 the intermediate valve 20. The flow rate of gas flowing into the gas range 10 is measured by the flow measurement sensor 60. Preferably, the gas leakage prevention system 100 according to the present invention has an alarm device 70, which generates a given alarm sound when in the event the first judging unit 30 determined that the gas range 10 is not ignited and the second judging unit 40 determined that the intermediate valve 20 is closed. Consequently, it is made possible to sense gas leakage in advance by abrasion of the intermediate valve 20, with the ignition device of the gas range 10 closed and the intermediate valve 20 closed. This allows a user to take proper measures such as replacing the intermediate valve 20.
Even if a sensor is installed not in external piping but only in internal piping as seen in the aforementioned embodiment, the sensor may be constructed as a pressure sensor for sensing gas pressure or a line leak detector for detecting gas leakage or the like as well as the aforementioned flow measurement sensor 60. Furthermore, as for the installation location of the flow measurement sensor 60, this embodiment has been exemplified with respect to the sensor 60 installed in piping between the gas range 10 and the intermediate valve 20, but the sensor 60 may be installed in piping between the intermediate valve 20 and a gas supply source, such as an outdoor gas tank or a gas supply of a gas provider. Alternatively, the flow measurement sensor 60 may be installed in each of the piping between the gas range 10 and the intermediate valve 20 and the piping between the intermediate valve 20 and the gas supply source. Furthermore, the present invention suggests a method of measuring flow rate and pressure and closing the intermediate valve 20 upon the sudden occurrence of gas leakage. That is, a critical value of a flow rate sensed by the flow measurement sensor 60 is set, usually based on the maximum gas volume supplied upon normal operation of the gas range 10. When a flow rate measured by the flow measurement sensor 60 exceeds this critical flow rate, it can be judged that gas is rapidly leaking out due to a damage to the piping between the intermediate valve 20 and the gas range 10, damage to the gas range 10 and so on. Accordingly, when a flow rate is sensed to exceed a critical value as set forth above, the intermediate valve 20 is closed. At this time, in the event that a pressure sensor is employed instead of the flow measurement sensor 60, generally used is a method in which a critical pressure is set based on the pressure of normal operation of the gas range 10
and, when a sensed pressure is lower than the critical value, this is determined to be a gas leak. Figs. 3a to 3c are a block diagram and views schematically illustrating another embodiment of the gas leakage prevention system according to the present invention. In this embodiment, as shown in Fig. 3a, a first detecting sensor 162 is installed on the pathway of gas between the intermediate valve 20 and a gas appliance (a gas range exampled in the drawing), and a second detecting sensor 161 is installed on the pathway of gas between the intermediate valve 20 and a gas supply source, such as an outdoor gas tank (for example, a gas supply of a gas provider). At this time, the first judging unit 30 and the second judging unit 40 determine the ignition state of the gas appliance and the opened or closed state of the intermediate valve 20, based on the detection results of the first detecting sensor 162 and the second detecting sensor 161 , respectively. In this embodiment, the gas leakage prevention system has the same basic construction as that shown in Fig. 1 , but the two detecting sensors 161 and 162 are installed at the inlet and outlet sides of the intermediate valve 20, respectively, in place of the flow measurement sensor 60 of Fig. 1. As illustrated in Fig. 3c, a gas range 10 is connected to a gas supply source, such as a gas supply of a gas provider or an outdoor gas tank, by piping 181 and 182. An intermediate valve 20 is installed at a halfway point of the two piping, which are the external piping 181 and the internal piping 182, and an appliance valve 11 is installed at a gas inlet side of the gas range 10 which is at the end of the internal piping 182. When the flow measurement sensor 60 is provided only in the internal piping 182, as in the previous embodiment, the opened or closed state of the appliance valve 11 is detected using the flow measurement sensor 60, and,
accordingly, the intermediate valve control unit 50 opens or closes the intermediate valve 20. However, when the detecting sensors 161 and 162 are installed on both sides of the intermediate valve 50, the opening and closing of the intermediate valve 20 can be controlled in the following manner. When both the intermediate valve 20 and the appliance valve 11 are. closed the detecting sensors 161 and 162 detect a condition in which there is no pressure change (or a condition in which the pressure is higher than a predetermined value) or a condition in which there is no flow rate change. In this state, when the appliance valve 11 is opened, the second detecting sensor 161 detects a pressure change (or a condition in which the pressure drops below a predetermined value) or flow rate change in the internal piping 182. (At this time, when the second detecting sensor 161 is a pressure sensor, it will detect a pressure decrease, or when the second detecting sensor 161 is a flow measurement sensor, it will determine a flow rate by the same principle as the flow measurement sensor 60 of the aforementioned embodiment.) Consequently, by the above-described procedure, a first judging unit 30 detects the opening of the appliance valve 11 and accordingly an intermediate valve control unit 50 opens the intermediate valve 20. On the other hand, it is possible to open the intermediate valve 20 only in case the second detecting sensor 161 detects a pressure change or flow rate change and at the same time the first detecting sensor 162 does not detect any pressure change or flow rate change. In this state, when the appliance valve 11 is closed, the first detecting sensor 162 detects a pressure change (or a condition in which the pressure is higher than a predetermined value) or a flow rate change. (At this time, when the first detecting sensor 162 is a pressure sensor, it will detect a pressure increase
or pressure value, or when the first detecting sensor 162 is a flow measurement sensor, it will determine a flow rate by the same principle as the flow measurement sensor 60 of the aforementioned embodiment.) When such a result is detected, the intermediate valve control unit 50 closes the intermediate valve 20. The closure of the intermediate valve 20 can be conducted on the basis of the result of detection of the first detecting sensor 162, or on the basis of the result of detection of the second detecting sensor 161 , or further on the basis of the results of detection of both the first detecting sensor 162 and the second detecting sensor 161. In case that both the first detecting sensor 162 and the second detecting sensor 161 are constructed as pressure sensor, it is also possible to control the intermediate valve 20 by using these two pressure sensors as a single differential sensor. In other words, when the appliance valve 11 is opened in an initial state (in which both the intermediate valve 20 and the appliance valve 11 are closed), the pressure in the external piping 181 will not change and the pressure in the internal piping 182 will decrease. Therefore, when there is a pressure difference between the piping 181 and the piping 182, the differential sensor senses this pressure difference. Accordingly, the intermediate valve control unit 50 judges that the appliance valve 11 is open, and the intermediate valve 20 is closed, and therefore opens the intermediate valve 20. Also, when the appliance valve 11 is closed in this state (in which both the intermediate valve 20 and the appliance valve 11 are open), the pressure will be increased while there will be no pressure difference. Therefore, the two detecting sensors 161 and 162 constituting the differential sensor detect this and the intermediate valve control unit 50 that the appliance valve 11 is closed, and the intermediate valve 20 is open, and therefore closes the intermediate valve 20.
When two detecting sensors 161 and 162 are employed in this way, there is a merit in that the opening and closing of the intermediate valve 20 can be controlled more precisely. In this embodiment, as in a modified example of the aforementioned embodiment, when the flow rate detected by the second detecting sensor 161 exceeds a critical flow rate or the pressure detected by the second detecting sensor 161 is less than a critical pressure, it is judged that gas is rapidly leaking out due to damage to the internal piping 182 or the like, and thus the intermediate valve 20 is closed. Preferably, each of the detecting sensors may be a flow measurement sensor capable of measuring gas flow in the piping, a pressure sensor capable of sensing pressure in the piping, or a line leak detector capable of detecting gas leakage from the piping. In the present invention, the flow measurement sensor, the pressure sensor or the line leak detector may be inserted into the piping, or may be integrated with the piping, or may be mounted to the outside of the piping, or may be configured as a unit which houses therein the sensor or the line leak detector and has opposite connection pipes directly connected to the piping. When the sensor or the line leak detector is configured as a unit, it may be possible to make the unit such that the unit more easily checks a change in the flow rate of gas by changing the diameters and lengths of the opposite connection pipes. In this embodiment, the two detecting sensors may be configured as two pressure sensors or two differential pressure sensors, or one flow measurement sensor, or one differential pressure sensor, or one pressure sensor. Thus, according to the use of the single or two sensors as the two detecting sensors, the opening and closing of the intermediate valve 20 may be controlled through a
plurality of methods by comparing the pressures or flow rates measured at the gas inlet side A and the gas outlet side B of the intermediate valve 20 of Fig. 3c as will be described herein below. In the following methods, it is preferred to provide a pressure regulator or a pressure regulation tank at the gas inlet side of the intermediate valve when one sensor is used as the two detecting sensors. First, when two pressure sensors or two differential pressure sensors are used as the two detecting sensors, the opening and closing of the intermediate valve is controlled as follows according to comparison results of the pressures measured by the two pressure sensors or the two differential pressure sensors. That is, the opening and closing of the intermediate valve in the above-mentioned case is controlled, with a minimum pressure difference Pc to ignite the gas appliance (gas range) preset as an initial value, such that, when the pressure PB of the gas outlet side B is lower than the pressure PA of the gas inlet side A, that is, PA>PB, the intermediate valve is opened, and when the pressure difference PA- PB between the gas inlet side and the gas outlet side is lower than the preset minimum pressure difference Pc to ignite the gas appliance (gas range), that is, PA-PB <PC> the intermediate valve is closed. The operation to open the intermediate valve is executed as follows. When the intermediate valve is in its initial state or remains in its closed state, there is no change in the flow rates at the gas inlet side and the gas outlet side so that the pressures measured at the gas inlet side and the gas outlet side are equal to each other, that is, PA=PB- When the gas range in the above state is operated, the pressure at the gas outlet side B is instantaneously reduced near to zero, so that the condition PA>PB to open the intermediate valve is provided. Thus, the intermediate valve is opened. In the above state, the aforementioned quick reduction in the pressure at the gas outlet side is made necessary by the fact that, when the gas range is operated,
the gas range draws air and gas from the gas outlet side B at very high velocities. The quick increase in the velocity of gas at the gas outlet side B induces the quick reduction in the pressure of gas at the gas outlet side. Second, when one flow measurement sensor is used as the two detecting sensors, the opening and closing of the intermediate valve is controlled as follows according to checking results of the flow rate QB at the gas outlet side B of the intermediate valve. That is, the opening and closing of the intermediate valve in the above-mentioned case is controlled such that, when the flow rate QB measured at the gas outlet side B is equal to or higher than a preset minimum flow rate Qc to ignite the gas range, that is, QB≥QC, the intermediate valve is opened, and when the flow rate QB is lower than the preset minimum flow rate Qc, that is, QB QC, the intermediate valve is closed. The operation to open the intermediate valve is executed as follows. The flow rate measurement at the gas outlet side and the control for the opening and closing of the intermediate valve are executed under the condition that the minimum flow rate Qc to ignite the gas range was preset as a reference value. When the intermediate valve is in its initial state or remains in its closed state, there is no flow of gas at the gas outlet side B, so that the flow rate QB measured at the gas outlet side B is near zero. When the gas range in the above state is operated, the flow rate QB (Q=AV, wherein Q is a flow rate of a fluid, A is a sectional area of a piping through which the fluid flows, and V is a fluid velocity) measured at the gas outlet side B is increased due to the velocity of gas drawn into the gas range. Thus, the condition QB≥QC to open the intermediate valve is provided, so that the intermediate valve is opened. The operation to close the intermediate valve is executed as follows. When the operation of the gas range is stopped, gas supply for the gas range is stopped so that gas is gradually
collected at a position around the gas range. When predetermined time has elapsed after the operation of the gas range was stopped, the flow rate QB at the gas outlet side B becomes lower than the preset minimum flow rate Qc to ignite the gas range, that is, QB<Qc, so that the intermediate valve is closed. Third, when one differential pressure sensor is used as the two detecting sensors, the opening and closing of the intermediate valve is controlled, with both a pressure difference between the gas inlet side and the gas outlet side to open the intermediate valve preset as a critical value Pγ and a minimum pressure difference Pc to ignite the gas appliance (gas range) preset as a reference value to close the intermediate valve, according to comparison results of the pressures measured at the gas inlet side and the gas outlet side in the same manner as that described for the example using the two pressure sensors or the two differential pressure sensors as the two detecting sensors. That is, when the difference PA- PB between the pressure PA at the gas inlet side A and the pressure PB at the gas outlet side B is equal to or higher than the preset critical value Pγ, that is, PA- PB≥PT, the intermediate valve is opened. However, when the pressure difference PA-PB is equal to or lower than the preset minimum pressure difference Pc to ignite the gas range, that is, PA-PB≤PC, the intermediate valve is closed. Fourth, when one pressure sensor is used as the two detecting sensors, the opening and closing of the intermediate valve is controlled according to a change in the pressure measured by the pressure sensor which is installed at the gas outlet side B under the condition that the pressure at the gas inlet side A is maintained constant. When the pressure at the gas inlet side A is maintained constant, there is no change in the flow rate at the gas outlet side B before the gas range is operated. Thus, the pressure PB at the gas outlet side B in the above state is maintained equal to the inlet gas pressure which is the pressure PA at the
gas inlet side A, that is, PA=PB- When the gas range in the above state is operated, the pressure PB at the gas outlet side B is quickly reduced lower than the inlet gas pressure due to gas which flows into the gas range, so that the intermediate valve is opened. The operation to close the intermediate valve is executed as follows. When the operation of the gas range is stopped, the pressure PB at the gas outlet side B becomes maintained at the inlet gas pressure because there is no change in the flow rate at the gas outlet side after predetermined time has elapsed. Thus, the intermediate valve is closed. In this embodiment, the opening and closing of the intermediate valve may be controlled according to comparison results of the pressure difference between the gas inlet side and the gas outlet side and a preset minimum pressure difference Pc to ignite the gas range. In practice, the inlet gas pressure at home using LNG supplied from a gas provider or LPG is not constant, but varies, so that, in the above-mentioned method of controlling the opening and closing of the intermediate valve, it is necessary to provide a pressure regulator or a pressure regulation tank at the gas inlet side to maintain the inlet gas pressure constant. When the opening and closing of the intermediate valve is controlled using a preset minimum pressure difference Pc to ignite a gas appliance as described above, the minimum pressure difference Pc may vary according to a variety of variables, such as the diameter of a unit, the model of the gas appliance and a difference in operational allowances between two pressure sensors. Therefore, the minimum pressure difference Pc is preferably determined in consideration of the above-mentioned variables. For example, when using LNG supplied from a gas provider, the minimum pressure difference Pc may be preset to a value within a range of 0~30mmAg. Furthermore, the pressure measurement capacities of pressure sensors
used in the above-mentioned methods are preferably determined according to the nature of gas supplied to a gas appliance and the inlet pressure of the gas. For example, when the inlet pressure of gas supplied to the gas appliance has a range of 200~300mmAg, it is most preferable to use a pressure sensor having a pressure measurement capacity of 0~300mmAg. However, it should be understood that, if another pressure sensor having a pressure measurement capacity of 0~10kg/cm2 can measure the gas pressure of 200~300mmAg, the pressure sensor of 0~1 Okg/cm2 may be used. The gas leakage prevention system 100 according to the present invention can be embodied to transmit an alarm signal generated by the alarm device 70 to a central management system 200, an embodiment of which will be illustrated in Fig. 4. Referring to the drawing, the central management system 200 is connected to gas leakage prevention systems 100 respectively installed in a plurality of houses. Here, the central management system 200 has an alarm signal receiving unit 210 and a display 220. The alarm signal receiving unit 210 is connected to alarm devices 70 respectively installed in a plurality of houses, and receives an alarm signal sent out from at least one alarm device 70. The display 220 displays the location of a corresponding house when the alarm signal is received by the alarm signal receiving unit 210. Preferably, alarm signals sent out from the alarm devices 70 of the individual houses are different from one another so that the display 220 can display the location of the individual houses in real time. Moreover, it is preferable that an alarm signal sending location shown on the display 220 is displayed so that an administrator administrating the central management system 200 can easily perceive it. One
example of an alarm signal sending location shown on the display 220 is shown in Fig. 5. Preferably, the location of a house where gas is leaking is displayed in a color contrasting with the location of a house where gas is not leaking. Fig. 6 is a flow chart showing a gas leakage prevention method using the gas leakage prevention system according to the present invention. The operation of the gas leakage prevention system according to the present invention will be described with reference to the accompanying drawing. A first judging unit 30 of the gas leakage prevention system 100 determined whether a gas range 10 is ignited or not (S601 ). The method of determined whether the gas range 10 is ignited or not by the first judging unit 30 is as set forth above. When the first judging unit 30 determined that the gas range 10 is not ignited (S603), a flow measurement sensor 60 installed in gas piping for in between the gas range 10 and an intermediate valve 20 determined whether gas is flowing into the gas range 10 (S605). A heat type air flow measurement sensor is used as the flow measurement sensor to detect a minute gas flow rate. The flow rate of incoming gas does not matter. Once the gas flowing into the gas range 10 has been detected by the flow measurement sensor 60, a second judging unit 40 determined whether the intermediate valve 20 is open or not (S607). When the second judging unit 40 determined that the intermediate valve 20 is closed, an alarm device 70 determined that a minute quantity of gas is leaking out due to the wear of the intermediate valve 20, and generates an alarm signal (S611 ). By this, the user of the gas leakage prevention system 100 can be aware of gas leaking out due to the wear of the intermediate valve 20 at an early stage
and thus can take proper measures, such as the replacement of the intermediate valve 20, immediately, thereby preventing a fire caused by a gas explosion. The gas leakage prevention system 100 according to the present invention can be connected to a central management system 200 arranged in an administration room in an apartment house, tenement house, multifamily housing, etc. In this case, an alarm signal sent out from the alarm device 70 is preferably transmitted to an alarm signal receiving unit 210 of the central management system 200 (S613). When the alarm signal receiving valve 210 of the central management system 200 receives an alarm signal from at least one of the alarm devices 70 respectively installed in a plurality of houses, it transmits the received alarm signal to a display 220 to display the location of the house from which the alarm signal is originating (S615). Therefore, when gas leaks out due to the aging of the intermediate valve 20, the administrator of the central management system 200 can take appropriate measures even in the situation in which the resident of the corresponding house cannot take immediate measures, thereby preventing a fire caused by a gas explosion. When the gas range 10 is not ignited but gas flow is detected by the flow measurement sensor 60, when the second judging unit 40 judges the intermediate valve 20 to be open, an intermediate valve control unit 50 closes the intermediate valve 20 to shut off the gas flowing into the gas range 10 (S617). Therefore, when the gas range 10 is extinguished as the user finishes using the gas range 10, the gas leakage prevention system 100 automatically closes the intermediate valve 20 to shut off the supply of gas flowing into the gas range 10.
When the gas range 19 is not ignited and the flow measurement sensor 60 determines that is not gas flowing into the gas range 10, the second judging unit 40 determined whether the intermediate valve 20 is open or not (S619). When the second judging unit 40 determined that the intermediate valve 20 is open (S621 ), the intermediate valve control unit 50 is able to prevent the risk of gas leakage by closing the intermediate valve 20 (S623). When the second judging unit 40 determined that the intermediate valve 20 is closed, this confirms a safe condition, and thus the intermediate valve is kept in a closed state (S625). When the first judging unit 30 judges the gas range 10 to be ignited (S603), the second judging unit 40 determined whether the intermediate valve 20 is opened or not (S629). When the second judging unit 40 determined that the intermediate valve 20 is open (S631 ), the intermediate valve control unit 50 determined that the user is using the gas range 10, and thus keeps the intermediate valve 20 in an open state (S625). When it is determined that the gas range 10 is ignited (S603) and the intermediate valve 20 is closed (S631 ), the intermediate valve control unit 50 determined that the user wants to use the gas range 10 and the temperature of a fire extinguishing safety device rises appropriately, and thus opens the intermediate valve 20 (S633). Therefore, even if the user does not open the intermediate valve 20 whenever using the gas range 10, the intermediate valve 20 is automatically opened, thereby increasing the user's convenience. Figs. 7a and 7b are block diagrams illustrating further embodiments of the gas leakage prevention system according to the present invention, to which an external sensor 260 is added. In the embodiment of Fig. 7a, the gas leakage
prevention system has the same basic construction as that shown in Fig. 1 , except for the additional provision of an external sensor. In the embodiment of Fig. 7b, the gas leakage prevention system has the same basic construction as that shown in Fig. 3a, except for the additional provision of an external sensor. The external sensor 260 additionally provided in this embodiment is installed at a predetermined position of a room where a gas range 10 is installed and senses gas leakage. Such a sensor is located in consideration of the type of gas supplied. More concretely, if a supplied gas is lighter than air, the sensor is installed at a region adjacent to the ceiling, or if the gas is heavier than air, the sensor is installed at a region adjacent to the floor. The sensing result of the external sensor 260 is transferred to an intermediate valve control unit 50. The intermediate valve control unit 50 closes the intermediate valve 20 when a gas leakage sensing signal is transferred from the external sensor 260 thereto. Hence, when gas leaks out due to the flame of a gas appliance being extinguished by food boiling over the intermediate valve 20 is closed to stop the supply of gas. In the embodiments set fort above, although a gas range has been described, the gas leakage prevention system according to the present invention is not limited thereto but may be applicable to a variety of gas appliances such as a gas oven, a gas boiler, etc. In the present invention, the 'intermediate valve' is installed directly in a region of the piping for providing a gas supply passage and a solenoid valve is used to carry out an automatic opening and closing operation. Besides this method, included is a method in which a manual fuse cock is electronically opened and closed by installing a motor on an opening and closing lever of the fuse cock and inserting only a sensor into the fuse cock without making a big
change to the fuse coke in order to utilize the merits of a conventional intermediate valve (fuse cock). An embodiment of this method is shown in Figs. 8 to 10. Referring to Figs. 8 to 10, a conventional intermediate valve 320 is installed between a steel gas pipe 181 as external piping and a rubber hose 182 ,as internal piping, and a sensor 370 is installed in the rubber hose 182 region adjacent to the intermediate valve 320. The sensor 370 performs the function as set forth above. An electric motor-operated lever device 350 is installed on the intermediate valve 320. The electric motor-operated lever device 350 comprises a main body 355, a lever 351 installed on the main body 355, a motor (not shown) installed within the main body 355 and rotatably driving the lever 351 , a driving control unit (not shown) installed within the main body 355 and driving the motor and a display unit 353 constructed as a display panel such as an LCD or the like. The main body 355, being placed on the intermediate valve 320, is fixed to the intermediate valve 320 by fixing frames. In this state, the lever 352 is coupled to the intermediate valve 320. Thus, when the motor is driven by the driving control unit within the main body 355, the lever 351 is rotated to rotate the intermediate valve 320. It is also possible to automatically open and close a manual knob type intermediate valve by external manipulation. The display unit 353 displays whether the intermediate valve 320 is currently open or closed. A display method of this display unit 353 includes a display method using characters, a method of displaying whether the intermediate valve 320 is opened or closed using a picture and so on. Further, the display unit 353 may be able to display the pressure measured by the sensor 370 in addition to whether the intermediate valve 320 is opened or closed.
In case the intermediate valve 320 is not constructed to be directly driven by the motor, electronic opening and closing are enabled by installing such an electric motor-operated lever device 350 on the intermediate valve 320.
Accordingly, the present invention is easily applicable to a conventional gas appliance with a manual manipulating type intermediate. According to the present invention, the gas leakage prevention system is able to prevent the risk of a fire caused by a gas explosion since it can sense gas leakage in real time when gas leaks out due to aging of the intermediate valve. Further, according to this invention, it is possible to automatically open or close the intermediate valve according to whether a gas appliance is used or not, thereby remedying the user's inconvenience in having to open/close the intermediate valve for each use. While the present invention has been described with reference to the preferred embodiments thereof, it is to be understood that the invention is not limited to the described embodiments or constructions. On the contrary, the invention is intended to cover various modifications and similar arrangements as would be apparent to those skilled in the art. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.
Claims
1. A gas leakage prevention system, comprising: a first judging unit for judging whether a gas appliance is ignited or not; a second judging unit for judging whether an intermediate valve installed in a passage of gas flowing into the gas appliance is open or closed; and an intermediate valve control unit for closing the intermediate valve when the first judging unit judges that the gas appliance is not ignited and the second judging unit determines that the intermediate valve is opened.
2. The system of claim 1 , wherein the intermediate valve control unit opens the intermediate valve when the first judging unit judges that the gas appliance is ignited and the second judging unit determines that the intermediate valve to be closed.
3. The system of claim 1 or 2, further comprising: a flow measurement sensor installed in a passage of gas between the gas appliance and the intermediate valve for measuring a flow rate of gas flowing into the gas appliance, wherein the intermediate valve control unit closes the intermediate valve when the first judging unit judges that the gas appliance is not ignited and the flow measurement sensor detects gas flowing into the gas appliance.
4. The system of claim 3, further comprising: an alarm device for generating a given alarm signal when the flow measurement sensor detects gas flowing into the gas appliance, when the first judging unit determines that the gas appliance is not ignited and the second judging unit determines that the intermediate valve is closed.
5. The system of claim 4, wherein the flow measurement sensor is a heat type air flow measurement sensor embodied in an MEMS (micro electro mechanical system).
6. The system of claim 4, further comprising: a receiving unit connected to alarm devices installed respectively in a plurality of houses for receiving an alarm signal sent out from at least one alarm device; and a display for displaying the location of a corresponding house when the alarm signal is received by the receiving unit.
7. The system of claim 1 or 2, further comprising: a first detecting sensor installed in a passage of gas between the intermediate valve and the gas appliance and a second detecting sensor installed in a passage of gas between the intermediate valve and a given gas supply source, wherein the first judging unit and second judging unit judge whether the gas appliance is ignited or not and whether the intermediate valve is opened or not on the basis of detection results of the first detecting sensor and the second detecting sensor, respectively, or on the basis of all the detection results of the first detecting sensor and the second detecting sensor.
8. The system of claim 7, wherein each of the first detecting sensor and the second detecting sensor includes either a flow measurement sensor, a pressure sensor, or a line leak detector.
9. The system of claim 8, wherein the first judging unit judges whether the gas appliance is ignited or not on the basis of a pressure measurement value, a pressure change or a flow rate change detected by the first detecting sensor, and the second judging unit judges whether the intermediate valve is opened or closed on the basis of a pressure measurement value, a pressure change or a flow rate change detected by the second detecting sensor.
10. The system of claim 8, wherein, when a flow rate higher than a predetermined critical value is detected by the flow measurement sensor or a pressure of less than a predetermined critical value is detected by the pressure sensor, the intermediate valve control unit closes the intermediate valve.
11. The system of claim 7, wherein the first detecting sensor and the second detecting sensor are configured as pressure sensors or differential pressure sensors to detect pressures in gas inlet side and gas outlet side of the intermediate valve, respectively, and the intermediate valve control unit compares the pressures detected in the gas inlet side and gas outlet side of the intermediate valve with each other, and controls the intermediate valve such that, when the pressure of the gas outlet side is lower than the pressure of the gas inlet side, the intermediate valve is opened.
12. The system of claim 11 , wherein the intermediate valve control unit controls the intermediate valve such that, when a pressure difference between the gas inlet side and the gas outlet side is lower than a minimum pressure difference to ignite the gas appliance, the intermediate valve is closed.
13. The system of claim 11 , wherein the first detecting sensor and the second detecting sensor are respectively connected to opposite sides of the intermediate valve which is configured as a unit having the gas inlet side and the gas outlet side with different diameters.
14. The system of claim 1 or 2, further comprising: a differential pressure sensor or a pressure sensor installed in a passage of gas between the gas appliance and the intermediate valve and measuring a pressure change in the gas outlet side of the intermediate valve, wherein the intermediate valve control unit controls the intermediate valve such that, when a pressure measured by the differential pressure sensor is lower than a reference pressure for the gas inlet side, the intermediate valve is opened.
15. The system of claim 14, wherein the intermediate valve control unit controls the intermediate valve such that, when a difference between the pressure measured by the differential pressure sensor and the reference pressure for the gas inlet side is lower than a minimum pressure difference to ignite the gas appliance, the intermediate valve is closed.
16. The system of claim 14, further comprising: a pressure regulator or a pressure regulation tank installed in a passage of gas between the intermediate valve and a given gas supply source and regulating the pressure in the gas inlet side of the intermediate valve, thus making the pressure in the gas inlet side constant.
17. The system of claim 7, wherein the first detecting sensor comprises a flow measurement sensor to measure a flow rate of gas, and the intermediate valve control unit controls the intermediate valve such that, when the flow rate of gas measured by the flow measurement sensor is higher than a minimum flow rate of gas to ignite the gas appliance, the intermediate valve is opened, and, when the flow rate of gas measured by the flow measurement sensor is equal to or lower than the minimum flow rate of gas to ignite the gas appliance, the intermediate valve is closed.
18. The system of claim 1 , further comprising: an external sensor installed at a predetermined position around the gas appliance and sensing gas, wherein the intermediate valve is closed when a gas leakage sensing signal is transferred from the external sensor thereto.
19. The system of claim 1 , further comprising: an electric motor-operated lever device installed on the intermediate valve for electrically controlling the opening and closing of the intermediate valve, wherein the intermediate valve control unit controls the opening and closing of the intermediate valve by driving the electric motor-operated lever device.
20. The system of claim 19, wherein the electric motor-operated lever device comprises: a main body installed on the intermediate valve; a lever installed on the main body and coupled to the intermediate valve; and a motor for driving the intermediate valve coupled to the lever by driving the lever.
21. The system of claim 20, wherein the electric motor-operated lever device further comprises a display unit provided on the main body for displaying whether the intermediate valve is opened or closed.
22. A gas leakage prevention method, comprising the steps of: (a) judging whether a gas appliance is ignited or not; (b) judging whether an intermediate valve installed in a passage of gas flowing into the gas appliance is open or closed; and (c) closing the intermediate valve when the gas appliance is judged to be not ignited in the step (a) and the intermediate valve is judged to be opened in the step (b).
23. The method of claim 22, further comprising the steps of: (d) measuring a flow rate of gas flowing into the gas appliance from a passage of gas between the gas appliance and the intermediate valve; and (e) closing the intermediate valve when the gas appliance is judged to be not ignited in the step (a) and gas is determined to be flowing into the gas appliance in the step (d).
24. The method of claim 23, further comprising the step of: (f) generating a given alarm signal when the gas appliance is judged to be not ignited in the step (a) and the intermediate valve is determined to be closed in the step (b), and the flow rate of gas flowing into the gas appliance is measured in the step (d).
25. The method of claim 24, further comprising the steps of: (g) receiving the alarm signal sent out from at least one of a plurality of alarm devices installed respectively in a plurality of houses; and (h) displaying the location of a corresponding house when the alarm signal is received in the step (g).
26. The method of claim 25, wherein whether the gas appliance is ignited or not in the step (a) is judged on the basis of a pressure measurement value, pressure change or a flow rate change detected in a passage of gas between the intermediate valve and the gas appliance, and whether the intermediate valve is open or closed in the step (b) is judged on the basis of a pressure measurement value, a pressure change or a flow rate change detected in a passage of gas between the intermediate valve and a predetermined gas supply source.
27. The method of claim 22, further comprising the steps of: (i) judging whether the flow rate in the passage of gas between the intermediate valve and the gas appliance is more than a predetermined critical flow rate or the pressure therein is less than a predetermined critical pressure; and 0) closing the intermediate valve when the flow rate is judged to be higher than the predetermined critical flow rate or the pressure is judged to be less than the predetermined critical pressure.
28. The method of claim 22, further comprising the step of: (k) judging whether gas is detected or not at a predetermined position around the gas appliance; and (I) closing the intermediate valve when gas is detected in the step (k).
Applications Claiming Priority (6)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR10-2004-0035518 | 2004-05-19 | ||
| KR1020040035518A KR20050117639A (en) | 2004-05-19 | 2004-05-19 | Gas leak prevention system and method using the same |
| KR10-2004-0081471 | 2004-10-12 | ||
| KR1020040081471A KR20050118068A (en) | 2004-05-19 | 2004-10-12 | Gas leakage prevention system and method using the same |
| KR1020050004432A KR100551958B1 (en) | 2004-10-12 | 2005-01-18 | Gas leakage prevention system and method using the same |
| KR10-2005-0004432 | 2005-01-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2005111962A1 true WO2005111962A1 (en) | 2005-11-24 |
Family
ID=35394361
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/KR2005/000931 WO2005111962A1 (en) | 2004-05-19 | 2005-03-31 | Gas leakage prevention system and method of using the same |
Country Status (1)
| Country | Link |
|---|---|
| WO (1) | WO2005111962A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8439072B2 (en) | 2010-10-22 | 2013-05-14 | International Business Machines Corporation | Hydrocarbon gas delivery system |
| CN106932043A (en) * | 2017-05-02 | 2017-07-07 | 华北理工大学 | Leakage-preventing intelligent gas meter |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0440828A1 (en) * | 1987-08-14 | 1991-08-14 | Hesham Hassan Gazzaz | Gas monitoring system with leak detection and flow cutoff |
| EP0632258A2 (en) * | 1993-06-29 | 1995-01-04 | Varian Associates, Inc. | Methods and apparatus for detection of large leaks |
| KR19980011955U (en) * | 1996-08-23 | 1998-05-25 | 김봉기 | Gas leakage alarm and remaining amount, gas tight, CO detection signal device |
| JP2002031580A (en) * | 2000-07-17 | 2002-01-31 | Yazaki Corp | Gas leak detection device and method |
-
2005
- 2005-03-31 WO PCT/KR2005/000931 patent/WO2005111962A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0440828A1 (en) * | 1987-08-14 | 1991-08-14 | Hesham Hassan Gazzaz | Gas monitoring system with leak detection and flow cutoff |
| EP0632258A2 (en) * | 1993-06-29 | 1995-01-04 | Varian Associates, Inc. | Methods and apparatus for detection of large leaks |
| KR19980011955U (en) * | 1996-08-23 | 1998-05-25 | 김봉기 | Gas leakage alarm and remaining amount, gas tight, CO detection signal device |
| JP2002031580A (en) * | 2000-07-17 | 2002-01-31 | Yazaki Corp | Gas leak detection device and method |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8439072B2 (en) | 2010-10-22 | 2013-05-14 | International Business Machines Corporation | Hydrocarbon gas delivery system |
| US8511345B2 (en) | 2010-10-22 | 2013-08-20 | International Business Machines Corporation | Detecting and automatically responding to airborne hydrocarbon gas |
| CN106932043A (en) * | 2017-05-02 | 2017-07-07 | 华北理工大学 | Leakage-preventing intelligent gas meter |
| CN106932043B (en) * | 2017-05-02 | 2023-09-08 | 山东齐智能源装备科技有限公司 | Leak-proof intelligent gas meter |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100551958B1 (en) | Gas leakage prevention system and method using the same | |
| KR100836072B1 (en) | Digital safety device for a gas valve | |
| JP6005062B2 (en) | Fluid leak detection system | |
| CN1954348A (en) | Gas leakage prevention system and method of using the same | |
| US20100212752A1 (en) | Shut Off Protection For Hot Water Heater | |
| AU2010246407B2 (en) | A header box for a furnace, a furnace including the header box and a method of constructing a furnace | |
| EP0562538B1 (en) | Gas burning apparatus | |
| US7250870B1 (en) | Back draft alarm assembly for combustion heating device | |
| US5322216A (en) | System and method for controlling outlet water temperature of an instantaneous water heater | |
| KR20110002409A (en) | Gas valve apparatus and the method thereof | |
| JP4956391B2 (en) | Fluid leak detection method | |
| JP4770507B2 (en) | Fluid safety device | |
| WO2005111962A1 (en) | Gas leakage prevention system and method of using the same | |
| KR0157359B1 (en) | Gas combustion apparatus | |
| WO2016205683A1 (en) | Fluid flow system | |
| KR200357849Y1 (en) | Gas leak prevention system | |
| JP3189475B2 (en) | Gas combustion equipment | |
| KR100862180B1 (en) | Automatic apparatus for shutting off the supply of gas | |
| JP3296359B2 (en) | Gas combustion equipment | |
| JP3558439B2 (en) | Safe combustion device | |
| JPH06317323A (en) | Control method of safety device for indoor setting type combustor | |
| KR100782963B1 (en) | An apparatus for sensing the flow of fluid | |
| JP2002139401A (en) | Leak monitoring apparatus for pipeline | |
| EP2952792A1 (en) | Electronic gas safety control means | |
| JP3191814B2 (en) | Gas combustion equipment |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AK | Designated states |
Kind code of ref document: A1 Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW |
|
| AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG |
|
| 121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
| WWE | Wipo information: entry into national phase |
Ref document number: 200580015773.6 Country of ref document: CN |
|
| NENP | Non-entry into the national phase |
Ref country code: DE |
|
| WWW | Wipo information: withdrawn in national office |
Country of ref document: DE |
|
| 32PN | Ep: public notification in the ep bulletin as address of the adressee cannot be established |
Free format text: NOTING OF LOSS OF RIGHTS PURSUANT TO RULE 69(1) EPC |
|
| 122 | Ep: pct application non-entry in european phase |