JP6576857B2 - Gas cutoff control device and control method - Google Patents

Description

  The present invention relates to a gas cutoff control device and a control method.

  The gas used by a consumer is supplied to each consumer via a gas pipe and a gas meter. In addition, the gas meter is obliged to be replaced at regular intervals according to the Measurement Law. When the gas meter is replaced, air remains in the replaced new gas meter. Therefore, after the gas meter is replaced, an operation for purging air remaining in the gas meter (hereinafter referred to as “residual air”) (hereinafter referred to as “purging operation”) is performed.

  Conventionally, when performing a purge operation, the cheese gas outlet provided in the gas outlet of the gas meter is opened, gas is supplied from the gas inlet to the gas meter, and residual air is diffused into the atmosphere through the gas outlet. Or burning on site. In recent years, a gas recovery container has been connected to the cheese gas discharge port via a conduit, and the purged residual air and the gas released in accordance with the purge operation are recovered in the gas recovery container. .

  As a technique for recovering residual air and gas in a gas recovery container, Patent Document 1 includes a plurality of conduits for connecting a gas outlet pipe connected to a gas meter and a gas recovery container, and each conduit has a flow control valve. There is disclosed a gas collection conduit set which is provided and the opening of the flow rate control valve is set so that the rated gas flow rates are different.

  Conventionally, when a gas meter is exchanged when there is no customer, an operator performs a purge operation by diffusing and collecting a certain amount of gas in the gas meter while visually checking the gas flow rate. After the purging operation, it was confirmed that the concentration of the gas supplied from the gas meter was equal to or higher than a predetermined concentration (for example, 90%) using an ignition test with a small burner or a portable gas detector.

JP 2011-202926 A

  In the conventional purging operation, since it is difficult to measure the concentration of gas during the purging, the amount of gas to be purged is determined for each size of the gas meter, and the gas concentration is measured after the purging is completed. For this reason, there has been a problem in that an excessive amount of gas is diffused and recovered while reaching a sufficient gas concentration. In addition, as a result, the time spent for replacing the gas meter becomes longer, and when the gas meter is replaced using the gas recovery container, the number of gas meters that can be replaced using one gas recovery container. There was a problem such as becoming less.

  In order to cope with this problem, a detecting means for detecting the concentration of gas flowing in from the gas meter via the gas outlet pipe is provided, and the concentration of the gas satisfies a predetermined criterion (for example, a predetermined concentration or more) In this case, a method of blocking the inflow of the gas can be considered.

  However, depending on the type of gas, the detection characteristics of the gas concentration by the detection means may differ. Accordingly, there is a problem that the gas inflow cannot be accurately blocked by the above-described method of blocking the gas inflow when a single determination criterion is satisfied regardless of the type of gas.

  The above problems are not only when the gas meter is replaced, but also when the gas meter is newly installed, or when the gas inlet pipe, gas outlet pipe, buried pipe buried underground, etc. are replaced or newly installed. is there.

  The present invention has been made in order to solve the above-described problems, and in accordance with the type of gas as compared with the case where the inflow of gas is cut off when a single criterion is satisfied regardless of the type of gas. It is an object of the present invention to provide a gas cutoff control device and a control method capable of accurately shutting off gas inflow.

In order to achieve the above object, a gas shutoff control device according to a first aspect of the present invention is a gas shutoff control device that is used by being connected to a member that serves as a gas flow path. A shutoff valve that shuts off the inflow of gas from the member, a detection means that detects the concentration of the gas in the gas flow path, and a recovery amount of the gas in the purge operation for purging the gas or the atmosphere of the gas Setting means for setting a safety level that decreases as the amount of emission to the gas increases, and when the concentration of the gas detected by the detection means satisfies a criterion set according to the type of gas, the cutoff Control to shut off the inflow of the gas by closing the valve , and the lower the safety level set by the setting means, the longer the period until the inflow of the gas is cut off. The above And a control means for controlling to shut off the inflow.
A gas shutoff control device according to a second aspect of the invention is a gas shutoff control device that is used by being connected to a member that serves as a gas flow path. The gas shutoff control device is provided so as to be openable and closable. A shutoff valve for shutting off the inflow of gas, a detecting means for detecting the concentration of gas in the gas flow path, and a determination criterion in which the concentration of gas detected by the detecting means is set according to the type of gas. And a control means for controlling the inflow of the gas by closing the shut-off valve when satisfied, wherein the control means has a predetermined concentration of the gas detected by the detection means. When the gas concentration is equal to or higher than the predetermined concentration, control is performed to block the inflow of the gas, and when the gas concentration is lower than the predetermined concentration, the determination criterion is added to the gas concentration. Unit of gas concentration Variation per also performs control to shut off the flow of the gas used.

In order to achieve the above object, the control method of the gas shut-off control device of the third invention is a gas shut-off control device used by being connected to a member serving as a gas flow path, and is provided to be openable and closable. In the closed state, the control method of the gas shutoff control device including a shutoff valve that shuts off the inflow of gas from the member, the gas concentration in the gas flow path is detected, and the detected gas concentration purge but if it meets the set criteria according to the type of the gas, the shut-off valve have the line control to cut off the flow of the gas by closed, At this time, the gas Until the safety level set by the setting means for setting the safety level that decreases as the amount of gas recovered or the amount of gas diffused into the atmosphere increases in the purging operation, the inflow of the gas is cut off. Lengthen the period Te includes performing control to cut off the flow of the gas.
The control method of the gas cutoff control device of the fourth invention is a gas cutoff control device that is used by being connected to a member that becomes a gas flow path, is provided so as to be openable and closable, and is closed from the member. A control method of a gas shutoff control device having a shutoff valve for shutting off the inflow of gas, wherein the gas concentration in the gas flow path is detected, and the detected gas concentration depends on the type of the gas When the determination criterion set in the above is satisfied, control is performed to shut off the inflow of the gas by closing the shut-off valve. At this time, the detected gas concentration is equal to or higher than a predetermined concentration. In some cases, control is performed to shut off the inflow of the gas, and when the concentration of the gas is less than the predetermined concentration, as the determination criterion, the concentration of the gas is added to the concentration of the gas. Using the amount of change per unit time Comprising performing a control to cut off the flow of serial gas.

  According to the present invention, it is possible to accurately block the inflow of gas according to the type of gas, compared to the case of blocking the inflow of gas when a single criterion is satisfied regardless of the type of gas. it can.

It is a front view which shows an example of a structure of the gas meter which concerns on each embodiment. It is a side view which shows an example of a structure of the gas meter which concerns on each embodiment. It is a perspective view which shows an example of a structure of the gas cutoff control apparatus which concerns on each embodiment. It is a block diagram which shows the principal part structure of the electric system of the gas cutoff control apparatus which concerns on each embodiment. It is a graph which shows the detection characteristic for every kind of gas by the concentration sensor which concerns on each embodiment. It is a flowchart which shows the flow of a process of the gas cutoff process program which concerns on 1st Embodiment. It is the schematic which shows an example of the gas type input screen which concerns on 1st Embodiment. It is the schematic which shows an example of the safety input screen which concerns on each embodiment. It is a flowchart which shows the flow of a process of the gas cutoff process program which concerns on 2nd Embodiment. It is a graph with which it uses for description of the responsiveness of the semiconductor type sensor which concerns on each embodiment. It is a graph which shows the detection characteristic of the density | concentration of the gas of a semiconductor type sensor.

  DETAILED DESCRIPTION Hereinafter, exemplary embodiments for carrying out the present invention will be described in detail with reference to the drawings.

[First Embodiment]
First, with reference to FIG. 1A and FIG. 1B, the structure of the gas meter to which the gas cutoff control device according to the present embodiment is connected will be described. FIG. 1A shows a front view of a gas meter according to the present embodiment, and FIG. 1B shows a side view of the gas meter shown in FIG. 1A viewed from the right side of FIG. 1A. As shown in FIGS. 1A and 1B, a gas meter 10 according to the present embodiment is connected to a gas inlet pipe 12 and an outlet pipe 14 provided so as to rise from the ground or the like of the installation site.

  The inlet pipe 12 and the outlet pipe 14 according to the present embodiment are connected to the gas meter 10 via a union nut 12A and a union nut 14A, respectively. The inlet pipe 12 is provided with a meter cock 16, and the outlet pipe 14 is provided with cheese 18. Further, a female screw is cut into the inner peripheral surface of the gas discharge port 18A (see FIG. 2) of the cheese 18, and a plug 18B is screwed into the female screw.

  Next, the configuration of the gas cutoff control device according to the present embodiment will be described with reference to FIG. As shown in FIG. 2, the gas cutoff control device 20 according to the present embodiment is for connecting the outlet pipe 14 and the gas recovery container 40 when the gas meter 10 is replaced. The gas cutoff control device 20 according to the present embodiment includes a first adapter 22, a hose 24, a vacuum breaker 26, a needle valve 28, a hose 30, a second adapter 32, a cutoff valve 34, a concentration sensor 36, and a control device 38. I have. The first adapter 22 is provided with a one-touch coupler 22A, and the second adapter 32 is also provided with a one-touch coupler 32A.

  The vacuum breaker 26 is opened when the pressure in the gas shut-off control device 20 becomes a predetermined pressure (for example, about 0.08 to 0.10 MPa as an absolute pressure) or less, and takes in the atmosphere from the inflow portion 26A to gas. It is comprised so that the negative pressure in the interruption | blocking control apparatus 20 may be eliminated or reduced. As the vacuum breaker 26, for example, a popular product having a structure in which a valve body is urged in a valve closing direction by a spring may be applied.

  The opening of the needle valve 28 is adjusted by turning the handle 28A. In the present embodiment, once the opening degree of the needle valve 28 is adjusted, so that the opening degree is not changed, the handle 28A is locked by a lock fitting, fixed by fixing a band, or by removing the handle 28A. The opening is fixed.

  The hose 24 and the hose 30 are preferably bendable flexibly including rubber, synthetic resin, and the like.

  Further, in the gas cutoff control device 20 according to the present embodiment, a cutoff valve 34 and a concentration sensor 36 are provided in the vicinity of the first adapter 22 of the hose 24. Specifically, the shut-off valve 34 is provided at a position where it can be installed with respect to the hose 24 and at a position closest to the first adapter 22. The concentration sensor 36 is provided at a position where it can be installed with respect to the hose 24 and at a position closest to the shutoff valve 34.

  The shutoff valve 34 according to the present embodiment is switched between an open state and a closed state under the control of the control device 38. In the open state, gas flows into the gas shutoff control device 20 from the gas discharge port 18A. The inflow of gas from the discharge port 18A into the gas cutoff control device 20 is blocked.

  The concentration sensor 36 according to the present embodiment is connected to the control device 38, detects the gas concentration in the gas cutoff control device 20 (in the hose 24 in the present embodiment), and detects the gas concentration in the control device 38. Output. In the present embodiment, a semiconductor sensor is applied as the concentration sensor 36 as an example, but the present invention is not limited to this. For example, as the concentration sensor 36, another sensor that can detect the concentration of gas in the gas cutoff control device 20 such as a galvanic cell type oxygen sensor may be applied. An example of the control device 38 is a portable information terminal.

  The gas recovery container 40 contains granular activated carbon in a container main body 42 containing synthetic resin, metal, etc., the container main body 42 is sealed with a cap 44, and the inside of the container main body 42 is vacuum level (for example, 0 to 0 as an absolute pressure). The pressure is reduced to about 0.095 MPa).

  An open / close valve 46 is provided on the upper portion of the container body 42. The opening / closing valve 46 is provided with a handle 46A for manual operation. An insertion port into which the coupler 32A of the second adapter 32 is screwed is provided in the adapter connection port 46B of the opening / closing valve 46.

  Next, with reference to FIG. 3, the principal part structure of the electric system of the gas interruption | blocking control apparatus 20 which concerns on this Embodiment is demonstrated. As shown in FIG. 3, the control device 38 according to the present embodiment includes a CPU (Central Processing Unit) 50 that controls the overall operation of the control device 38, and a ROM ( Read Only Memory) 52 is provided. The control device 38 includes a RAM (Random Access Memory) 54 used as a work area when the CPU 50 executes various programs, and a nonvolatile storage unit 56 such as a flash memory.

  In addition, the control device 38 includes a display unit 58 that notifies the user of various types of information regarding the operating status of the control unit 38 and an operation unit 60 that receives various instructions from the user. The display unit 58 and the operation unit 60 may be integrated using, for example, a touch panel display. The CPU 50, ROM 52, RAM 54, storage unit 56, display unit 58, operation unit 60, shut-off valve 34, and concentration sensor 36 are connected to one another via a bus 62.

  With the above configuration, the control device 38 according to the present embodiment performs access to the ROM 52, RAM 54, and storage unit 56 by the CPU 50. In addition, the control device 38 causes the CPU 50 to display various types of information on the display unit 58 and acquire various types of data via the operation unit 60. In addition, the control device 38 controls the opening and closing of the shutoff valve 34 and the acquisition of the concentration of the gas output from the concentration sensor 36 by the CPU 50.

  By the way, the detection characteristic of the gas concentration by the concentration sensor 36 according to the present embodiment differs depending on the type of gas. FIG. 4 shows an example of detection results of propane and methane concentrations by the concentration sensor 36. In FIG. 4, as an example, for each of propane and methane, components other than gas such as oxygen and nitrogen are from 100% to 10% methane, components other than gas are 90%, and components other than gas. Shows a time-series transition of detection results when the state transitions from a state of 100% to a state of 10% propane and 90% of components other than gas.

  4 represents the output value of the density sensor 36, and the horizontal axis in FIG. 4 represents the period. Also, the solid line in FIG. 4 indicates the detection result of the methane concentration, and the alternate long and short dash line in FIG. 4 indicates the detection result of the propane concentration. Moreover, the broken line of FIG. 4 has shown the timing which started mixing of each of methane and propane. The output value of the concentration sensor 36 can be converted as a gas concentration. In this embodiment, as an example, the gas concentration when the output value of the concentration sensor 36 is 5.0 [V] is 100%. Convert.

  As shown in FIG. 4, even if the concentrations of propane and methane are each 10%, the output values from the concentration sensor 36 are different. Further, the degree of increase in output value after the start of mixing of propane and methane is also different. The detection characteristics of the concentration sensor 36 are similarly different between so-called propane gas mainly containing propane and so-called methane gas mainly containing methane. Therefore, in the present embodiment, the determination criteria (values of concentration N1 and threshold value V1 to be described later) for determining whether or not to shut off the gas are different depending on the type of gas.

  Next, a procedure for replacing the gas meter 10 will be described.

  First, the worker closes the meter cock 16, then loosens the union nuts 12 </ b> A and 14 </ b> A and removes the existing gas meter 10 from the inlet pipe 12 and outlet pipe 14. Further, the worker connects the new gas meter 10 to the inlet pipe 12 and the outlet pipe 14 with union nuts 12A and 14A. The worker attaches caps to the gas inlet and outlet for the removed gas meter 10 and takes them home after the work is completed.

  Next, after attaching the new gas meter 10 to the inlet pipe 12 and the outlet pipe 14 as described above, the worker removes the plug 18B from the cheese 18, and the first adapter of the gas shut-off control device 20 with respect to the gas discharge port 18A. 22 is connected. Further, the worker connects the second adapter 32 of the gas cutoff control device 20 to the opening / closing valve 46. Through the above operation, the outlet pipe 14 and the gas recovery container 40 are connected via the gas cutoff control device 20.

  Next, the worker confirms that the shut-off valve 34 is open, and if the shut-off valve 34 is closed, the worker opens the shut-off valve 34. Further, the worker turns on the power of the concentration sensor 36 and the control device 38, and instructs the control device 38 to start execution of a gas shut-off processing program (see FIG. 5) described later via the operation unit 60. .

  Next, with reference to FIG. 5, the operation of the gas cutoff control device 20 according to the present embodiment will be described. FIG. 5 is a flowchart showing the flow of processing of the gas cutoff processing program executed by the CPU 50 of the control device 38. The gas shut-off processing program is installed in the ROM 52 in advance.

  In step 100 of FIG. 5, the CPU 50 causes the display unit 58 to display a gas type input screen for allowing the operator to input the gas type. In the next step 102, the CPU 50 waits for an input of the gas type.

  FIG. 6 shows an example of a gas type input screen displayed by the display unit 58 by the processing in step 100 described above. As shown in FIG. 6, on the gas type input screen according to the present embodiment, a message for prompting the operator to input the gas type and a character string indicating the gas type are displayed. In this embodiment, methane gas and propane gas are applied as the types of gas.

  The operator designates a check box corresponding to the type of gas to be worked through the operation unit 60 and then uses the operation unit 60 to display an end button displayed near the lower end of the gas type input screen. Specify. When the end button of the gas type input screen is designated by the worker, the above step 102 becomes affirmative and the process proceeds to step 104.

  In step 104, the CPU 50 sets values of a concentration N1 and a threshold value V1, which will be described later, according to the type of gas input by the operator on the gas type input screen. Specifically, for example, when the type of gas is a type of gas (methane gas in the present embodiment) in which the value detected by the concentration sensor 36 and the actual gas concentration are relatively close to each other, the concentration N1 is used. Is set to 90%, and the threshold value V1 is set to 10%. Further, for example, when the gas type is a type of gas (propane gas in the present embodiment) in which the value detected by the concentration sensor 36 is higher than the actual gas concentration, the concentration N1 and the threshold value V1 are set to methane gas. Set to a lower value. In the present embodiment, in the case of propane gas, for example, the concentration N1 is set to 45%, and the threshold value V1 is set to 5%.

  The concentration N1 is a lower limit value of the concentration of gas in the gas cutoff control device 20 that can be regarded as having been purged by the new gas meter 10 by an experiment using an actual machine of the gas cutoff control device 20 or the like. A concentration determined in advance for each type of gas may be applied. Similarly, as for the threshold value V1, a value determined in advance for each type of gas may be applied by an experiment using an actual machine of the gas cutoff control device 20. In addition, type information indicating the type of gas may be stored in the storage unit 56 in advance. In this case, the CPU 50 may read the type information stored in the storage unit 56 and determine the type of gas.

  In step 106, the CPU 50 causes the display unit 58 to display a safety level input screen for allowing the worker to input the safety level of work. In the next step 108, the CPU 50 waits for input of the safety level.

  FIG. 7 shows an example of the safety level input screen displayed by the display unit 58 by the processing of step 106 described above. As shown in FIG. 7, on the safety level input screen according to the present embodiment, a message for prompting the worker to input the safety level and a character string indicating the safety level are displayed. In the present embodiment, three levels of high, medium and low are applied as the degree of safety. However, the present invention is not limited to this, and two steps may be applied, or four or more steps may be applied. In the present embodiment, high safety means that the amount of collected gas is small and the gas is shut off early. In the present embodiment, the low degree of safety means that the remaining air in the new gas meter 10 is reliably purged even if the amount of recovered gas increases. Further, in the present embodiment, the medium safety level indicates that the safety level is intermediate between the low safety level and the high safety level.

  The operator specifies a check box corresponding to the safety level required for the work via the operation unit 60, and then specifies an end button displayed near the lower end of the safety level input screen via the operation unit 60. To do. When the end button of the safety degree input screen is designated by the worker, the above step 108 becomes affirmative and the process proceeds to step 110. In addition, after the operator designates the end button on the safety input screen, the operator opens the meter cock 16 and turns the handle 46A to open the opening / closing valve 46. As a result, the gas flows into the new gas meter 10 from the inlet pipe 12, and the residual air in the gas meter 10 is pushed out by the gas and begins to be recovered in the gas recovery container 40 via the gas cutoff control device 20. In addition, you may make a worker input the above kind of gas and safety | security degree by one screen. In addition, safety level information indicating the safety level may be stored in the storage unit 56 in advance. In this case, the CPU 50 may read the safety level information stored in the storage unit 56 and determine the safety level.

  In step 110, the CPU 50 acquires the concentration of gas in the gas cutoff control device 20 output from the concentration sensor 36. In the next step 112, the CPU 50 stores the gas concentration acquired by the processing in step 110 in the RAM 54. In step 112, the CPU 50 may store the gas concentration acquired by the processing in step 110 in a storage unit other than the RAM 54 such as the storage unit 56.

  In the next step 114, the CPU 50 determines whether or not the concentration of the gas acquired by the processing in step 110 is equal to or higher than the concentration N1. When this determination is a negative determination, the CPU 50 proceeds to the process of step 124, and when this determination is a positive determination, the CPU 50 proceeds to the process of step 116.

  In step 116, the CPU 50 determines the safety level input on the safety level input screen. Specifically, when the safety level is high, the CPU 50 proceeds to the process of step 134. When the safety level is medium, the CPU 50 proceeds to the process of step 118, and when the safety level is low. , The process proceeds to step 122.

  In step 118, an average value of the concentration of the gas detected by the concentration sensor 36 in the most recent fixed period (for example, the period in which the gas concentration for five times is acquired by the processing in step 110) is derived.

  In the next step 120, it is determined whether or not the average value derived by the processing in step 118 is equal to or higher than the density N1. When this determination is negative, the CPU 50 returns to the process of step 110. When this determination is affirmative, the CPU 50 proceeds to step 134.

  In step 122, it is determined whether or not all the gas concentrations detected by the concentration sensor 36 in the most recent fixed period are equal to or higher than the concentration N1. When this determination is negative, the CPU 50 returns to the process of step 110. When this determination is affirmative, the CPU 50 proceeds to step 134.

  In step 124, the CPU 50 determines the safety level input on the safety level input screen. Specifically, when the safety level is high, the CPU 50 proceeds to the process of step 126. When the safety level is medium, the CPU 50 proceeds to the process of step 130, and when the safety level is low. Then, the process returns to step 110.

  In step 126, the CPU 50 uses the gas concentration stored in the RAM 54 by the previous processing of step 112 and the latest gas concentration acquired by the previous processing of step 110 per unit time (this embodiment). In the embodiment, the amount of change (increase) in the gas concentration is derived per second. In the next step 128, the CPU 50 determines whether or not the amount of change derived in the process of step 126 is equal to or greater than the threshold value V1. When this determination is negative, the CPU 50 returns to the process of step 110. When this determination is affirmative, the CPU 50 proceeds to step 134.

  In step 130, the CPU 50 derives the amount of change in the gas concentration per unit time, as in the process of step 126. In the next step 132, the CPU 50 determines whether or not the sum of the concentration of the gas acquired by the process of the previous step 110 and the amount of change derived in the process of step 130 is greater than or equal to the concentration N1. When this determination is negative, the CPU 50 returns to the process of step 110. When this determination is affirmative, the CPU 50 proceeds to step 134.

  In step 134, the CPU 50 shuts off the inflow of gas from the gas discharge port 18A by closing the shutoff valve 34. In the next step 136, the CPU 50 displays a message indicating that the inflow of gas from the gas discharge port 18A has been blocked on the display unit 58, and then ends the gas blocking process program.

  The worker confirms the message displayed on the display unit 58 by the process of step 136, then closes the meter cock 16 and turns the handle 46A to close the open / close valve 46. Further, the worker removes the first adapter 22 from the cheese 18, attaches the plug 18 </ b> B to the cheese 18, and then opens the meter cock 16. Thereby, the replacement work of the gas meter 10 is completed.

  As described above, according to the present embodiment, determination criteria (in this embodiment, the values of the concentration N1 and the threshold value V1) according to the type of gas (in this embodiment, methane gas and propane gas). Are different. Therefore, the inflow of gas can be accurately blocked according to the type of gas.

  Moreover, in this Embodiment, the period until it interrupts | blocks inflow of gas is lengthened, so that the safety | security level of work becomes low. Therefore, the inflow of gas can be blocked for a period according to the required safety level of work.

  In the present embodiment, a semiconductor sensor is applied as the concentration sensor 36. The response of the semiconductor sensor will be described with reference to FIG. The vertical axis on the left side of FIG. 9 indicates the concentration of gas in the gas cutoff control device 20, and the vertical axis on the right side of FIG. 9 indicates the concentration of oxygen in the gas cutoff control device 20. In addition, the horizontal axis of FIG. 9 indicates the elapsed time, and “0” (zero) represents the point in time when the inflow of gas from the gas discharge port 18A to the gas cutoff control device 20 is started. 9 indicates an example of the gas concentration detected by the semiconductor sensor when a semiconductor sensor is applied as the concentration sensor 36, and corresponds to the left vertical axis in FIG.

  9 indicates an example of the concentration of oxygen detected by the galvanic cell type oxygen sensor when the galvanic cell type oxygen sensor is applied as the concentration sensor 36, and corresponds to the vertical axis on the right side of FIG. . The upper limit of the oxygen concentration on the right vertical axis in FIG. 9 is about 21% because the atmosphere contains about 80% of nitrogen and the upper limit corresponds to a gas concentration of 0%. This is because. Further, the oxygen concentration of 0% on the right vertical axis in FIG. 9 corresponds to the gas concentration of 100%.

  In the shut-off control device 20 according to the present embodiment, the gas concentration in the shut-off control device 20 reaches 100% in a short time of about 1 second after the start of gas inflow. In the example shown in FIG. 9, the semiconductor sensor detects that the gas concentration has reached 100% in about 10 seconds, whereas the galvanic cell oxygen sensor has reached 100%. Is detected in about 60 seconds.

  Thus, the semiconductor type sensor has better responsiveness to gas concentration detection than the galvanic cell type oxygen sensor. That is, when the semiconductor sensor is applied as the concentration sensor 36, it can be determined that the condition for blocking the inflow of gas is satisfied earlier than when the galvanic cell oxygen sensor is applied. Therefore, according to the present embodiment, since the semiconductor sensor is applied as the concentration sensor 36, the excessive gas release is suppressed as compared with the case where the galvanic cell oxygen sensor is applied as the concentration sensor 36. be able to.

  In particular, by applying a MEMS (Micro Electro Mechanical Systems) type semiconductor sensor as the concentration sensor 36, the power consumption of the concentration sensor 36 can be reduced and the installation position of the concentration sensor 36 can be reduced. The degree of freedom can be increased.

  As shown in FIG. 10, the semiconductor sensor can detect the gas concentration with high accuracy even when the gas concentration is 90% or more. FIG. 10 shows the detection characteristics of the city gas (13A) concentration by the semiconductor sensor, the vertical axis shows the output value of the semiconductor sensor, and the horizontal axis shows the gas concentration.

  If the determination in step 114 is negative, the process may return to step 110 without executing steps 124 to 132.

[Second Embodiment]
In the first embodiment, the case where the type of gas is input by the operator via the operation unit 60 has been described. In the present embodiment, a case where the CPU 50 determines the type of gas will be described. In addition, since the structure of the gas meter 10, the gas interruption | blocking control apparatus 20, and the gas collection | recovery container 40 which concerns on this Embodiment is the same as that of the said 1st Embodiment (refer FIGS. 1-3), here. The description of is omitted. In addition, the procedure for exchanging the gas meter 10 according to the present embodiment is also the same as that in the first embodiment, and thus the description thereof is omitted here.

  With reference to FIG. 8, the operation of the gas cutoff control device 20 according to the present embodiment will be described. FIG. 8 is a flowchart showing the flow of processing of the gas cutoff processing program executed by the CPU 50 of the control device 38. The gas shut-off processing program is installed in the ROM 52 in advance. Further, steps in FIG. 8 that execute the same processing as in FIG. 5 are denoted by the same step numbers as in FIG.

  In step 150 of FIG. 8, the CPU 50 acquires the concentration of gas in the gas cutoff control device 20 output from the concentration sensor 36 as in the processing of step 110. In the next step 152, the CPU 50 stores the gas concentration acquired by the process of step 150 in the RAM 54, similarly to the process of step 112.

  In the next step 154, the CPU 50 determines whether or not a predetermined period T1 has elapsed since the time when the process of step 150 was first executed. When this determination is negative, the CPU 50 returns to the process of step 150. When this determination is affirmative, the CPU 50 proceeds to step 156. Note that, as the predetermined period T1, the actual gas concentration in the gas cutoff control device 20 after the gas flows into the gas cutoff control device 20 by an experiment using an actual machine of the gas cutoff control device 20 is as follows. What is necessary is just to apply a predetermined period as a period until it reaches a predetermined concentration (for example, 50%) lower than the reference concentration for blocking the inflow of gas.

  In the next step 156, the CPU 50 determines the type of gas using the concentration of the gas stored in the RAM 54 by the repeated processing from step 150 to step 154. And CPU50 sets the value of density | concentration N1 and threshold value V1 according to the determined kind of gas similarly to the process of the said step 104. FIG.

  Here, the gas type determination method in step 156 will be described. The CPU 50 uses the gas concentration stored in the RAM 54 by the repeated processing from step 150 to step 154 to change the gas concentration per unit time (in this embodiment, per second) within the predetermined period T1. Deriving the amount (amount of increase). Then, the CPU 50 determines that the type of gas is propane gas when the derived change amount is equal to or greater than a predetermined threshold value V2 (for example, 10%). On the other hand, when the derived change amount is less than the threshold value V2, the CPU 50 determines that the gas type is methane gas.

  As described above, according to the present embodiment, the same effects as those of the first embodiment can be obtained. Moreover, according to this Embodiment, since the kind of gas is determined automatically, an operator's effort can be reduced.

  Although each embodiment has been described above, the technical scope of the present invention is not limited to the scope described in each embodiment. Various modifications or improvements can be added to the above-described embodiments without departing from the gist of the invention, and embodiments to which the modifications or improvements are added are also included in the technical scope of the present invention.

  In addition, each of the above embodiments does not limit the invention according to the claims (claims), and all combinations of features described in each embodiment are indispensable for solving means of the invention. Not necessarily. Each embodiment described above includes inventions at various stages, and various inventions are extracted by combining a plurality of disclosed constituent elements. Even if several constituent requirements are deleted from all the constituent requirements shown in the respective embodiments, the configuration from which these several constituent requirements are deleted can be extracted as an invention as long as the effect is obtained.

  For example, in each of the above embodiments, the case where the purge operation is performed using the gas recovery container 40 has been described, but the present invention is not limited to this. It is good also as a form which diffuses gas in the air | atmosphere from the gas cutoff control apparatus 20, without using the gas collection container 40. FIG.

  Moreover, although each said embodiment demonstrated the case where it alert | reports that the inflow of gas was interrupted | blocked by the display part 58, this invention is not limited to this. For example, a speaker may be provided in the control device 38, and a sound may be output from the speaker to notify that the inflow of gas has been blocked. Further, for example, a vibrator may be provided in the control device 38, and the vibrator may be vibrated to notify that the inflow of gas has been blocked.

  In each of the above embodiments, the case where two types of gas are applied has been described, but the present invention is not limited to this. For example, three or more types of gas may be applied. In this case, the form which sets the density | concentration N1 and the threshold value V1 for every kind of gas is illustrated. In this case, in the second embodiment, the threshold value V2 is set in advance as a value of a plurality of steps, and the gas type is determined.

  Moreover, although each said embodiment demonstrated the case where the density | concentration sensor 36 detected the density | concentration of the gas in the gas interruption | blocking control apparatus 20 (in the hose 24), this invention is not limited to this. For example, the concentration sensor 36 is provided at a position where the gas concentration in the other gas flow path such as the gas meter 10, the inlet pipe 12, and the outlet pipe 14 can be detected. The gas concentration may be detected.

  Moreover, although each said embodiment demonstrated the case where the gas interruption | blocking control apparatus 20 was used at the time of replacement | exchange of the gas meter 10, this invention is not limited to this. For example, the gas cutoff control device 20 may be used when the gas meter 10 is newly installed. Further, the gas cutoff control device 20 may be configured to be used when other members such as the inlet pipe 12, the outlet pipe 14, and a buried pipe buried in the ground are replaced or newly installed. In these cases as well, as in the above embodiments, the gas shut-off device 20 is connected to a member serving as a gas flow path, and a concentration sensor 36 is provided at a position where the concentration in the gas flow path can be detected. Based on the gas concentration detected by the sensor 36, the gas flowing into the gas shutoff control device 20 may be shut off using the shutoff valve 34.

  Moreover, although each said embodiment demonstrated the case where the gas cutoff process program was previously installed in ROM52, this invention is not limited to this. For example, the gas cutoff processing program may be provided by being stored in a storage medium such as a CD-ROM (Compact Disk Read Only Memory), or provided via a network.

  Further, although cases have been described with the above embodiments where the gas shut-off process is realized by a software configuration using a computer by executing a program, the present invention is not limited to this. For example, the gas cutoff process may be realized by a hardware configuration or a combination of a hardware configuration and a software configuration.

  In addition, the configurations (see FIGS. 1 to 3) of the gas meter 10, the gas shut-off control device 20, and the gas recovery container 40 described in the above embodiments are merely examples, and within the scope not departing from the gist of the present invention. Needless to say, unnecessary parts may be deleted or new parts may be added.

  Further, the flow of processing of the gas cutoff processing program described in the above embodiments (see FIGS. 5 and 8) is also an example, and unnecessary steps can be deleted without departing from the gist of the present invention. Needless to say, a new step may be added or the processing order may be changed.

  Furthermore, the configurations of various screens described in the above embodiments (see FIGS. 6 and 7) are also examples, and unnecessary information is deleted or new information is added within the scope of the present invention. Needless to say, can be added or the display state can be changed.

DESCRIPTION OF SYMBOLS 10 ... Gas meter, 14 ... Outlet pipe, 20 ... Gas shut-off control device, 34 ... Shut-off valve, 36 ... Concentration sensor, 38 ... Control device, 40 ... Gas recovery container, 50 ... CPU, 52 ... ROM, 60 ... Operation part

Claims (7)

A gas cutoff control device used by being connected to a member that becomes a gas flow path,
A shut-off valve that is provided so as to be openable and closable and that shuts off the inflow of gas from the member in a closed state;
Detection means for detecting the concentration of gas in the gas flow path;
Setting means for setting a safety level that decreases as the amount of gas recovered or the amount of gas diffused into the atmosphere increases in the purging operation for purging the gas;
When the concentration of the gas detected by the detection means satisfies a criterion set according to the type of the gas, control is performed to shut off the inflow of the gas by closing the shutoff valve. Control means for performing control to cut off the gas inflow by extending a period until the gas inflow is cut off, as the safety level set by the setting means is lower ,
A gas shut-off control device. A gas cutoff control device used by being connected to a member that becomes a gas flow path,
A shut-off valve that is provided so as to be openable and closable and that shuts off the inflow of gas from the member in a closed state;
Detection means for detecting the concentration of gas in the gas flow path;
When the concentration of the gas detected by the detection means satisfies a criterion set according to the type of the gas, control is performed to shut off the inflow of the gas by closing the shutoff valve. Control means;
With
The control means performs control for blocking the inflow of the gas when the concentration of the gas detected by the detection means is equal to or higher than a predetermined concentration, and the concentration of the gas is the predetermined concentration. If it is less than that, the control for blocking the inflow of the gas is performed using the amount of change per unit time of the gas concentration in addition to the gas concentration as the determination criterion.
Gas shut-off control device. The shutoff valve shuts off the inflow of gas from the gas outlet connected to the gas meter in the closed state,
The detection means detects the concentration of gas flowing in from the gas outlet pipe.
The gas cutoff control device according to claim 1 or 2 . The gas cutoff control device according to any one of claims 1 to 3, further comprising determination means for determining the type of the gas. The gas cutoff control device according to any one of claims 1 to 4 , wherein the detection means is a semiconductor sensor . A gas shut-off control device that is used by being connected to a member that forms a gas flow path, and is provided so as to be openable and closable, and includes a shut-off valve that shuts off the inflow of gas from the member in a closed state. Control method,
Detect the gas concentration in the gas flow path,
When the detected concentration of the gas satisfies a determination criterion set according to the type of the gas, the control is performed to shut off the inflow of the gas by closing the shutoff valve. , The lower the safety level set by the setting means for setting the safety level, the lower the safety level, the lower the safety level set by the setting means for setting the safety level of the gas in the purging operation for purging the gas. Control to cut off the inflow of gas by extending the period until the inflow is cut off
A control method for a gas cutoff control device . A gas shut-off control device that is used by being connected to a member that forms a gas flow path, and is provided so as to be openable and closable, and includes a shut-off valve that shuts off the inflow of gas from the member in a closed state. Control method,
Detect the gas concentration in the gas flow path,
The concentration of the detected said gas is if it meets the set criteria according to the type of the gas, had a row control to block the flow of the gas by the shut-off valve in the closed state, this time In addition, when the detected gas concentration is equal to or higher than a predetermined concentration, control is performed to block the inflow of the gas, and when the gas concentration is lower than the predetermined concentration, the determination is performed. As a reference, a control method for a gas shut-off control device including performing control for shutting off the inflow of gas using a change amount per unit time of the gas concentration in addition to the gas concentration .