JP2611083B2 - Gas leak detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas leak detecting device for detecting a small leak of a supply pipe including a buried pipe in a liquefied petroleum gas supply facility, and particularly to a gas supply facility having a plurality of consumers where the gas supply facility is normal or abnormal. The present invention relates to a gas leak detection device for diagnosing the above.

[0002]

2. Description of the Related Art Conventionally, as this type of apparatus, for example, an apparatus as shown in FIG. 8 disclosed in Japanese Patent Application Laid-Open No. 3-41300 has been proposed. FIG. 8 shows a gas supply system incorporating a switchable gas leak detection device for supplying gas to an apartment house such as an apartment, for example. In FIG. 8, a gas supply source 1 such as a propane gas cylinder and a gas inlet 3 of an apartment 2 are shown. Are connected by a gas supply pipe 4. The gas supply pipe 4 is provided with pressure regulators 5 and 6 and a gas meter 7. The gas inlet 3 is provided with, for example, valves 8 and 9 for each floor, and each house in the apartment 2 is supplied with gas to a gas consuming facility 13 by a pipe 12 via a valve 10 and a gas meter 11, respectively. You.

A master controller 6 is provided on a gas supply pipe 4b between a main controller 5 on the propane gas cylinder 1 side serving as a gas supply source and a master gas meter 7 for accumulating the amount of gas supplied to the entire apartment 2. In addition, the gas supply pipe 4b is provided with a bypass gas flow path 14 that connects the inlet side and the outlet side of the master adjuster 6. The gas flow path 14 is provided with a child adjuster 15 and a microcomputer gas meter (hereinafter, referred to as an M meter) 16 as a minute leak detecting means in order from the inlet side.

The adjustment pressure of the child adjuster 15 is set higher than the adjustment pressure of the master adjuster 6. For example, when the adjustment pressure of the parent adjuster 6 is set to 280 mmH ₂ O, the adjustment pressure of the child adjuster 15 is set to about 300 mmH ₂ O. The M meter 16 can accurately accumulate a very small flow rate, for example, a flow rate of about 3 liters / hour, and monitors the flow rate by a minute leak detection function. Is determined to have occurred, and the fact is displayed by lighting the lamp.

In the above configuration, when gas consumption is almost zero during the night or at midnight, the pressure of the gas supply pipe 4b increases, the parent regulator 6 is closed, and the child regulators 15 and M
The gas flows only through the meter 16 so that a minute gas flow rate flowing through the gas supply path 4b can be monitored. At this time, if there is no gas consumption and no minute leakage of gas occurs, both the parent gas meter 7 and the M meter 16 do not detect the gas flow rate.

It is assumed that such a phenomenon occurs at least once during a relatively long predetermined period of, for example, 30 days. If the parent gas meter 7 and the M meter 16 both have a gas flow rate during this predetermined period, When the detection of the gas does not stop, it can be determined that the minute gas leakage has occurred.

As described above, a bypass flow path is provided in a part of a gas supply pipe, and gas flows through the bypass flow path at a low flow rate by regulators having different adjustment pressures, and a minute flow rate provided in the bypass flow path can be detected. Since a minute gas leak is detected by monitoring the flow rate by the meter, the gas leak detection of the gas supply pipe can be easily and reliably performed without stopping the gas supply.

[0008]

In the above-described conventional gas leak detecting device, a small leak of gas is detected on the assumption that the master adjuster 6, the slave adjuster 15 and the M meter 16 are functioning normally. However, even if any of these functions is impaired, accurate detection cannot be performed.

Although the functions of the parent adjuster 6 and the child adjuster 15 can be checked once a year, the inspection frequency of the above-described device assuming constant monitoring is not sufficient. Too much, there is a possibility that the device may go unnoticed even if it becomes inoperable at the time of equipment deterioration or sudden accident.

Further, an M meter 1 as a minute flow rate monitoring means.
As for the function of detecting that there is a gas flow rate of 3 liters / hour or more according to 6, there is no inspection work to confirm at all, and no maintenance is actually performed at all.
It cannot be chucked on-site as to whether the function is normal.

Accordingly, the present invention has been made in consideration of the above-described conventional problems, and has the advantage that the reliability of the gas leak detection function can be monitored by constantly monitoring whether or not the constituent devices, the master regulator and the slave regulator, are functioning normally. The main object of the present invention is to provide a gas leak detection device capable of increasing the gas leakage.

In view of the above-mentioned conventional problems, the present invention can constantly monitor whether or not the minute flow rate monitoring means, which is a constituent device, is functioning normally, thereby further improving the reliability of the gas leak detection function. It is a second object to provide a gas leak detection device that can be increased.

[0013]

In order to achieve the above-mentioned main object, a gas leak detecting device made according to the present invention is shown in FIG.
As shown in the basic configuration diagram of FIG. 2, a gas regulator 14 having a higher regulation pressure than the parent regulator 6 and a gas regulator 1 are provided in a gas flow path 14 that bypasses the parent regulator 6 provided in the gas supply pipe 4b.
A first flow rate detecting means Q2 for detecting the flow rate of No. 4;
In the gas leak detecting device in which the first flow rate detecting means Q2 continuously detects a flow rate for a predetermined period to detect a minute gas leak, the pressure at the outlet side of the child regulator 15 is detected. A first pressure detecting means P2, a second pressure detecting means P1 for detecting the pressure on the outlet side of the master adjuster 6, and a second pressure detecting means for detecting a flow rate of gas supplied to the consumer.
The parent adjustment is performed based on the pressures detected by the first and second pressure detecting means P2 and P1 when both the flow rate detecting means Q1 and the first and second flow detecting means Q2 and Q1 do not detect the flow rate. Pressure detecting means 18a for diagnosing the closing pressure of the controller 6 and the child regulator 15, and detecting by the second pressure detecting means P1 when the second flow detecting means Q1 detects a flow rate equal to or more than a predetermined value. The first supply pressure diagnosing means 18b for diagnosing the supply pressure of the master regulator 6 based on the detected pressure, and the first supply pressure diagnosing means when the second flow rate detecting means Q1 does not detect a flow rate equal to or more than a predetermined value. The second supply pressure diagnosing means 18c for diagnosing the supply pressure of the child adjuster 15 based on the pressure detected by the pressure detecting means P2, or the second flow rate detecting means Q1 detects a flow rate equal to or more than a predetermined value. And a third supply pressure diagnosing means 18d for diagnosing the supply pressure of the child regulator 15 based on the difference between the pressures detected by the first and second pressure detecting means P2 and P1 when there is no such pressure. .

As shown in FIG. 1, the gas leak detecting device according to the present invention for achieving the second object has a minute flow detecting means S for detecting a predetermined minute flow in the gas flow path 14, A minute flow rate detecting and diagnosing means 18e for diagnosing the first flow rate detecting means Q2 based on a match / mismatch between the flow rate detected by the minute flow rate detecting means S and the flow rate detected by the first flow rate detecting means Q2. It is characterized by:

[0015]

In the above construction, the child regulator 15 having a higher adjustment pressure than the parent regulator 6 is provided in the gas flow path 14 bypassing the parent regulator 6, and the first flow detecting means Q2 for detecting the flow rate in the gas flow path 14 is provided. The first flow rate detecting means Q2 detects that there is a flow rate continuously for a predetermined period to detect a minute gas leak.

The first pressure detecting means for detecting the pressure at the outlet side of the child regulator 15 when both the first flow detecting means Q2 and the second flow detecting means Q1 do not detect the flow rate. The closing pressure of the parent regulator 6 and the child regulator 15 is diagnosed based on the pressure detected by the means P2 and the second pressure detecting means P1 for detecting the pressure on the outlet side of the parent regulator 6.

The first supply pressure diagnosing means 18b detects the parent regulator 6 based on the pressure detected by the second pressure detecting means P1 when the second flow detecting means Q1 detects a flow rate equal to or more than a predetermined value. Diagnose supply pressure. The second supply pressure diagnosing means 18c detects the first pressure detecting means P2 when the second flow detecting means Q1 does not detect a flow rate equal to or more than a predetermined value.
The supply pressure of the child adjuster 15 is diagnosed on the basis of the pressure detected by the above. Alternatively, the third supply pressure diagnostic means 18d
When the second flow detecting means Q1 does not detect a flow rate equal to or more than a predetermined value, the first and second pressure detecting means P2 and P
The difference between the pressures detected by step 1 diagnoses the supply pressure of the child regulator 15 based on the pressure difference.

The minute flow rate detecting / diagnosing means 18e determines whether or not the flow rate detected by the minute flow rate detecting means S for detecting a predetermined minute flow rate in the gas flow path 14 and the flow rate detected by the first flow rate detecting means Q2 match. 1 flow rate detection means Q
Diagnose 2.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows an embodiment of a switching type gas leak detecting device according to the present invention incorporated in a gas supply facility. In FIG. 2, the same reference numerals are given to the same or equivalent parts as those in the conventional example described above with reference to FIG. is there.

The main regulator 5 on the propane gas cylinder side, which is a gas supply source, and the parent gas meter 7 for integrating the supplied gas amount
At the outlet side of the master adjuster 6 provided in the gas supply pipe 4b between the main adjuster and the master adjuster pressure sensor P for detecting the internal pressure thereof
1 is provided at the outlet side of the child adjuster 15 provided in the bypass flow path 14 with a child adjuster pressure sensor P2 for detecting the internal pressure thereof.

The parent gas meter 7 for integrating the supplied gas amount
For example, a diaphragm type having a diaphragm that reciprocates when a certain amount of gas flows is applied. The diaphragm type parent gas meter 7 is, for example, a reed switch that generates a flow rate pulse signal by being opened and closed by a magnet that rotates in conjunction with reciprocation of the diaphragm when a gas of, for example, 0.5 m ² / hour or more flows. The flow rate detection switch Q1 is built in. A diaphragm type meter similar to the parent gas meter 7 is also applied to the M meter 16 provided in the bypass flow path 14, and a gas of, for example, 3 liters / hour or more flows through the M meter 16 so that a flow rate pulse signal is generated. Is built in. A minute flow rate detection switch Q2 for generating a pressure is generated.

The bypass flow path 14 is provided with a minute flow rate sensor S which is turned on when a flow rate of, for example, 3 liters / hour or more is provided between the child regulator 15 and the M meter 16. FIGS. 3 and 4 show the minute flow rate sensor S.
The structure shown in FIG.

The sensor of FIG. 3 has the fluid inlet 17a downward,
The sphere 17c is housed in the cylinder 17 with the fluid outlet 17b facing upward. This sensor is shown in FIG.
As shown in FIG. 3, the fluid inlet 17a and the fluid outlet 17b
Bypass channel 1 provided between the inlet and outlet of meter 16
The pressure difference between the inlet and the outlet of the M meter 16 when there is a flow rate acts between the fluid inlet 17a and the fluid outlet 17b of the sensor.

The sphere 17c in the cylinder 17 is
When the pressure difference between the fluid a and the fluid inlet 17b occurs when the flow rate of the fluid flowing through the M meter 16 is less than 3 liters / hour, it is located at the position shown by the solid line due to its own weight, but is 3 liters / hour. Is exceeded, the pressure rises to the position shown by the dotted line due to the differential pressure generated at the time of the flow rate. Therefore, by detecting the position of the sphere 17c, it is possible to know whether the flow rate is 3 liters / hour or less. As a method of detecting the position of the sphere 17c, a method using a proximity magnetic switch, a photoelectric tube, or the like can be considered.

In the sensor shown in FIG. 4, the sphere 17c is biased by a coil spring 17d in a direction against the differential pressure,
At the differential pressure generated when the flow rate is less than 3 liters / hour, it is at the position indicated by the solid line due to the urging force, but when the flow rate exceeds 3 liters / hour, it is moved to the position indicated by the dotted line against the urging force. Become so. Therefore, by detecting the position of the sphere 17c by the same method as in the case of the sensor of FIG. 3, it can be known whether the flow rate is 3 liters / hour or more.

The pressure sensor P1 for the parent regulator, the pressure sensor P2 for the child regulator, the flow rate detection switch Q1, the minute flow rate detection switch Q2, and the minute flow rate confirmation sensor S are constituted by a microcomputer (CPU) which operates according to a predetermined program. Signal line 1 to the controller 18
9 are connected to each other, and a signal generated by each is input to the controller 18 and processed.

The controller 18 diagnoses the basic functions of the master adjuster 6, the child adjuster 15, and the M meter 16 in addition to the diagnosis of the minute gas leakage. As a specific example, the parent regulator 6 has a closing pressure of 335 mmH ₂ O or less and an output (supply) pressure at an actual flow rate of 310 to 255 mm.
Normal at H ₂ O. Child regulator 15, the occlusion pressure at 345mmH ₂ O or less, the flow rate 0.2～0.3Kg /
Output (supply) pressure in time is 330-310 mmH ₂
At the time of O, or when the supply from the parent regulator 6 is stopped and the supply is started only from the child regulator 15, the difference between the closing pressure of the parent regulator 6 and the output pressure of the child regulator 15 is +1.
It is normal when 0 mm H ₂ O or more. On the other hand, M meter 1
6 is normal when a very small flow rate of 3 liters / hour or less can be measured.

The parent adjuster 6 and the child adjuster 15 as described above.
The basic function is diagnosed by the controller 18 making a determination based on the pressure detection by the master regulator pressure sensor P1 and the child regulator pressure sensor P2 and the detection of the presence / absence of a flow rate of 3 liters / hour by the M meter 16. Also,
The basic function of the M meter 16 is diagnosed based on whether or not the controller 18 has detected a flow rate of 3 liters / hour by the minute flow rate confirmation sensor S. Note that the child adjuster 15
Is in the range of 0.2 to 0.6 kg / hour (0.1 to 0.3 m ³ / hour), the parent regulator 6 is in the operating state by the flow pulse signal of 0.5 m ³ / hour. Can be determined.

The details of the operation outlined above will be described below with reference to the flowcharts of FIGS. 5 to 7 showing the work performed by the CPU constituting the controller 18.

FIG. 5 is a flowchart showing an embodiment of the apparatus according to the present invention. In step S1, which is executed in response to the start of the operation, the flow rate is measured by the flow rate pulse signal from the minute flow rate detection switch Q2 of the M meter 16. When the flow rate measurement is completed, the process proceeds to step S2, where the flow rate measurement by the flow rate pulse signal from the flow rate detection switch Q1 of the parent gas meter 7 is completed, and when the flow rate measurement is completed, the process proceeds to step S3. Proceed to.

In step S3, it is determined whether or not both the flow rates Q1 and Q2 measured by the flow rate pulse signals from the flow rate detection switches Q1 and Q2 are both 0. When the determination is YES, that is, when the master gas meter 7 If no gas is flowing through the M meter 16 and the flow proceeds to step S4. In step S4, the micro leak timer is cleared, and then the process proceeds to step S5.

In this step S5, it is determined whether or not the pressure P2 is equal to or less than the closing pressure 345 mmH ₂ O of the child regulator 15 based on the pressure signal from the child regulator pressure sensor P2. If YES, the process proceeds to step S6. Pressure P1 is equal to or less than or equal to the closing pressure 335mmH ₂ O parent regulator 6 by the pressure signal from the main adjustment dexterity pressure sensor P1 in step S6, the determination is YE
In the case of S, it is determined that the closing pressure of the master adjuster 6 or the slave adjuster 15 is normal, and the process returns to step S1. on the other hand,
When the determination in step S5 or S6 is NO, that is,
It is determined that there is an abnormality in the closing pressure of the parent adjuster 6 or the child adjuster 15 and the process proceeds to step S7 to display an abnormality. In step S8, the fact is notified to the outside by communication, and the process returns to step S1. .

When the determination in step S3 is NO, that is, when one or both of Q1 and Q2 are not 0, the process proceeds to step S9, where it is determined whether or not Q1 is equal to or greater than 0.5 m ³ / hour, ie, It is determined whether or not the parent regulator 6 is operating. If the determination is YES, the process proceeds to step S10, where P1 is equal to or equal to the upper limit value 310 mmH ₂ O of the outlet (supply) pressure of the parent regulator 6. to determine a whether or less, the process proceeds to step S11 when this determination is YES, here whether P1 is greater than or equal to the lower limit 255mmH ₂ O outlet pressure of the parent regulator 6 If the determination is YES, the process returns to step S1. On the other hand, if the determination in step S10 or S11 is NO, that is, if the supply pressure of the master adjuster 6 is not within the predetermined pressure range, the process proceeds to step S7, where the abnormality display is performed as described above and After reporting to the outside by communication, the process returns to step S1.

When the determination in step S9 is NO, that is, when the parent adjuster 6 is not operating, step S9 is executed.
Then, it is determined whether or not Q2 is 3 liters / hour or more, that is, whether or not the gas flowing to the M meter 16 is 3 liters / hour or more.
In the case of S, the process proceeds to step S13. In step S13, it is determined whether or not the minute flow rate confirmation sensor S is turned on. This is based on the premise that the state of the minute flow rate confirmation sensor S is correct. When it is, it is for diagnosing whether or not the M meter 16 is normal by turning on the minute flow rate confirmation sensor S.

When the determination in step S13 is NO, the process proceeds to step S7, where an error display and notification are made, and the process returns to step S1. On the other hand, the determination in step S13 is YE
In the case of S, the process proceeds to step S14 and Q2 is set to 0.1 to 0.1.
It is determined whether it is 5 m ³ / hour.

If the determination in step S14 is YES, the function of the child adjuster 16 is checked in step S14.
Proceed to 15 P2 I am determined whether there are less than or equal to 330mmH ₂ O, the judgment at Step S15 Y
In the case of ES, the process proceeds to step S16, where P2 is 310 mm.
Determines whether the H ₂ O equal to or greater. That is, in steps S15 and S16, P2 is determined whether or not within the scope of 310~330mmH ₂ O, step S when the judgment is no abnormality is YES
Returning to step 1, if the determination is NO, the process proceeds to step S7, where an abnormality display and notification are made. On the other hand, when the determination in step S14 is NO, that is, when the flow rate is not suitable for performing the function check, the process immediately returns to step S1.

When the determination in step S12 is NO, that is, when Q2 is 3 liters / hour or less, the flow advances to step S17 to determine whether or not the minute flow rate sensor S is off. This determination is YES. If so, the process proceeds to step S14. In step S17, it is determined whether or not the minute flow confirmation sensor S is off. This is based on the assumption that the state of the minute flow confirmation sensor S is correct.
When the measurement result 2 indicates that the flow rate is 3 liters / hour or less, the micro flow rate check sensor S is turned off to diagnose whether the M meter 16 is normal. . If the determination in step S17 is NO, the process proceeds to step S7, where an abnormality display and notification are made, and the process returns to step S1.

6A and 6B, when a flow rate pulse signal is input from the M meter 16 or the parent gas meter 7 in the course of executing the work of steps S1 to S17.
The flow measurement operation of Q1 and Q2 shown in FIG. Further, the timer interrupt operation shown in FIG. In the timer interrupt operation, it is determined whether or not one day has passed in the first step S10a, and if this determination is YES, the process proceeds to step S10a.
When the answer is NO, the interrupt operation is terminated without any operation and the process returns to the original job.

In step S10b, the count of the minute leak timer is counted up, and the process proceeds to step S10c.
Here, it is determined whether or not the content of the counter is equal to 30,
When the determination is NO, the interrupt operation ends here.
When the determination in step S10c is YES, Q1 and Q2 do not both become 0 for 30 consecutive days, it is determined that a minute leak has occurred, and the process proceeds to step S10d to perform a warning start process. End the interrupt operation.

In the embodiment of FIG. 5, it is checked whether P2 is within the predetermined pressure range when Q2 is within the predetermined range for function diagnosis of the M-meter 16. However, steps S12 to S12 in the flowchart of FIG. By changing S17 as shown in FIG. 7, when the parent regulator 6 is closed and gas of 3 liters / hour or more is flowing through the M meter 16, the pressure on the outlet side of the child regulator 15 can be reduced. Diagnosis can be made based on whether or not the pressure difference between P2 and the pressure P1 on the outlet side of the master regulator 6 is equal to or greater than a predetermined value.

In the flowchart of FIG. 7, step S1
If the determination in Step 3 is YES, the process proceeds to Step S18, and P
After measuring P2 in the next step S19, the process proceeds to step S20, where the difference between P2 and P1, that is, the differential pressure P is obtained. Then, the differential pressure P obtained in this step S20 it is judged whether it is equal to or greater than 10 mm H ₂ O, return to the original step S1 as the determination is normal when YES, the judgment is N
In the case of O, it is determined that there is an abnormality, the process proceeds to step S7, and an abnormality display and notification are performed. In the flowchart of FIG. 7, when the determination in step S17 is YES, the process immediately returns to step S1.

In the embodiment described above with reference to FIG.
Using the pressure sensor P1 and the pressure sensor P2
However, in the embodiment of the flowchart of FIG.
Sensor P1 is 335mmH_TwoO, 310mmH_TwoO, 255mm
H_TwoWith a pressure switch that can detect the pressure at three points of O
And the sensor P2 is 345 mmH _Two
O, 330mmH_TwoO, 310mmH_TwoCheck the pressure at three points of O
Can be replaced by a known pressure switch
You.

When the function diagnosis of the M meter 16 is not performed, the process proceeds to step S14 when the determination in step S9 is NO in the flowchart of FIG. 5, and proceeds to step S14 when the determination in step S9 is NO in the flowchart of FIG. S
18, and go to steps S12, S13 and S1, respectively.
7 may be omitted.

As is clear from the above description of the flow chart, the controller 18 executes the steps S3, S5 and S6 of the flow chart of FIG. 5 to control the minute flow rate detection switch Q2 and the minute flow rate detection switch Q2 as the first and second flow rate detection means. When both of the flow rate detection switches Q1 do not detect the flow rate, the parent regulator 6 based on the pressure detected by the child regulator pressure sensor or switch P2 and the parent regulator pressure sensor or switch P1 as the first and second pressure detecting means. And functions as closing pressure diagnosing means 18a for diagnosing the closing pressure of the child adjuster 15.

The controller 18 also performs step S9,
By executing S10 and S11, when the flow rate detection switch Q1 is detecting a flow rate equal to or more than a predetermined value, the first pressure for diagnosing the supply pressure of the parent regulator 6 based on the pressure detected by the parent regulator pressure sensor or the switch P1. Of the supply pressure diagnostic means 18b.

The controller 18 further performs step S9,
By executing steps S14 to S16, when the flow rate detection switch Q1 does not detect a flow rate equal to or more than the predetermined value, the second control unit diagnoses the supply pressure of the child regulator 15 based on the pressure detected by the child regulator pressure sensor or the switch P2. When the flow rate detection switch Q1 does not detect a flow rate equal to or more than a predetermined value, the pressure sensor for the child regulator or the switch P2 and the supply pressure diagnostic means 18c for the parent regulator. The pressure difference detected by the pressure sensor or the switch P1 serves as third supply pressure diagnosis means 18d for diagnosing the supply pressure of the child regulator 15 based on the difference.

The controller 18 further performs step S
By executing steps S12, S13, and S17, the flow rate detected by the minute flow rate detection sensor S as the minute flow rate detection means matches the flow rate detected by the minute flow rate detection switch Q2.
It functions as a minute flow rate detecting and diagnosing means 18e for diagnosing the minute flow rate detecting switch Q2 based on the mismatch.

In the above-described embodiment, the parent gas meter 7 for integrating the amount of gas supplied to the entire apartment is used as the second gas flow detecting means Q1 for detecting the gas flow supplied to the consumer. A flow rate detecting means may be provided in the gas meter 11 of each house of the condominium, and a gas flow rate supplied to the entire condominium to be consumed may be detected by a flow rate pulse signal from the flow rate detecting means.

[0049]

As described above, according to the present invention, the function of diagnosing the closing pressure based on the pressures at the outlets of the child regulator and the parent regulator when the gas is not flowing is provided. The function of diagnosing the supply pressure of the parent regulator based on the pressure at the outlet of the parent regulator when gas is flowing, and the function of diagnosing the supply pressure of the child regulator based on the pressure at the exit side of the child regulator when gas not exceeding a predetermined value is not flowing. It has a function of diagnosing the supply pressure of the regulator or diagnosing the supply pressure of the child regulator by the difference between the pressures on the outlet side of the parent regulator and the child regulator when the flow rate is not more than a predetermined value. It is possible to constantly monitor whether the master adjuster and the slave adjuster, which are devices, are functioning normally, and the reliability of the gas leak detection function can be improved.

Further, a means for detecting a predetermined minute flow rate in the bypass gas flow path is separately provided so that the function of the means for detecting the flow rate in the bypass gas flow path can be diagnosed.
It is possible to constantly monitor whether the minute flow rate monitoring means is functioning normally, and the reliability of the gas leak detection function can be further improved.

[Brief description of the drawings]

FIG. 1 is a diagram showing a basic configuration of a gas leak detection device according to the present invention.

FIG. 2 is a diagram showing one embodiment of a gas leak detection device according to the present invention.

FIG. 3 is a diagram showing an example of a minute flow rate confirmation sensor in FIG. 2;

FIG. 4 is a diagram showing another example of the minute flow rate confirming sensor in FIG. 2;

FIG. 5 is a flowchart showing a part of a task performed by a controller in FIG. 2;

FIG. 6 is a flowchart illustrating another part of the work performed by the controller in FIG. 2;

FIG. 7 is a diagram showing a modification of a part of the flowchart of FIG. 5;

FIG. 8 is a diagram showing an example of a conventional device.

[Explanation of symbols]

 4b Gas supply pipe 6 Parent regulator 14 Gas flow path 15 Child regulator Q1 Second flow detecting means Q2 First flow detecting means P1 Second pressure detecting means P2 First pressure detecting means S Micro flow detecting means 18a Blocking pressure diagnostic means 18b First supply pressure diagnostic means 18c Second supply pressure diagnostic means 18d Third supply pressure diagnostic means 18e Micro flow rate detection diagnostic means

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location G01M 3/28 G01M 3/28 B G05D 16/00 G05D 16/00 N 16/06 16/06 K G08B 21/00 G08B 21/00 W

Claims (3)

(57) [Claims] 1. A child regulator having a higher regulation pressure than a parent regulator in a gas flow path bypassing a parent regulator provided in a gas supply pipe, and first flow detecting means for detecting a flow rate in the gas flow path. Wherein the first flow rate detecting means detects the presence of a flow rate continuously for a predetermined period to detect a minute gas leak, wherein a pressure at an outlet side of the child adjuster is detected. A first pressure detecting means, a second pressure detecting means for detecting a pressure on an outlet side of the master regulator, a second flow detecting means for detecting a flow rate of gas supplied to a consumer, Occlusion pressure diagnosis for diagnosing the occlusion pressure of the parent regulator and the child regulator based on the pressure detected by the first and second pressure detection means when both the first and second flow detection means do not detect the flow rate. Means, the second flow rate detecting means First supply pressure diagnosis means for diagnosing the supply pressure of the master regulator based on the pressure detected by the second pressure detection means when detecting a flow rate equal to or more than a predetermined value; and the second flow rate detection A second supply pressure diagnosing means for diagnosing the supply pressure of the child regulator based on the pressure detected by the first pressure detecting means when the means does not detect a flow rate equal to or higher than a predetermined value. Gas leak detection device. 2. A child regulator having a higher regulation pressure than a parent regulator in a gas flow path bypassing a parent regulator provided in a gas supply pipe, and a first flow rate detecting means for detecting a flow rate in the gas flow path. In the gas leak detecting device, wherein the first flow rate detecting means detects the flow rate continuously for a predetermined period to detect the minute gas leak, the pressure on the outlet side of the child adjuster is A first pressure detecting means for detecting, a second pressure detecting means for detecting a pressure on an outlet side of the master regulator, a second flow detecting means for detecting a flow rate of the gas supplied to the consumer. A blockage for diagnosing a blockage pressure of the parent regulator and the child regulator based on the pressure detected by the first and second pressure detectors when both the first and second flow detectors do not detect a flow rate; Pressure diagnostic means, and the second flow rate A first supply pressure diagnostic unit for diagnosing a supply pressure of the master regulator based on a pressure detected by the second pressure detection unit when the informing unit detects a flow rate equal to or more than a predetermined value; A second supply pressure diagnosing means for diagnosing a supply pressure of the child regulator based on a difference between pressures detected by the first and second pressure detection means when the flow rate detection means does not detect a flow rate equal to or more than a predetermined value. A gas leak detection device comprising: 3. A minute flow rate detecting means for detecting a predetermined minute flow rate in the gas flow path, and the flow rate detected by the minute flow rate detecting means and the flow rate detected by the first flow rate detecting means match or disagree with each other. 3. The gas leak detecting device according to claim 1, further comprising: a minute flow rate detecting and diagnosing means for diagnosing the first flow rate detecting means.