JP2002168400A - Self-diagnostic method of regulated pressure and gas leakage detecting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas leakage detecting apparatus that can self-diagnose the regulated pressure of a master pressure regulator and a slave pressure regulator without driving a shut-off valve. SOLUTION: A bypass gas passage is partitioned based on a gas flow rate corresponding to an intersection of respective performance curves indicating relations between the gas flow rate and pressure of the master pressure regulator 6 and the slave pressure regulator 15. The gas leakage detecting apparatus comprises: a monitoring flow late block memory means 22a for storing monitoring flow rate block information on a monitoring flow rate block for monitoring a pressure change amount; a threshold memory means 22b for storing a threshold determined corresponding to the pressure change amount in the monitoring flow rate block when the regulated pressure is normal; a pressure change amount measuring means 21a1 for measuring the pressure change amount in the monitoring flow rate block corresponding to the monitoring flow rate block information; and a diagnosis means 21a2 for diagnosing the regulated pressure based on a result of the comparison of the pressure change amount measurement by the pressure change amount measuring means 21a1 and the threshold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for self-diagnosis of regulated pressure and a gas leak detecting device.

[0002]

2. Description of the Related Art Conventional liquefied propane gas (hereinafter, LP)
A gas leak detection device that detects leakage of a gas supply pipe including a buried pipe of a supply facility particularly supplies gas to a plurality of gas consumers in an apartment house such as an apartment or an apartment. As a gas leak detection device used in a gas supply system or the like, for example, Japanese Unexamined Patent Publication No.
There is a switch-type gas leak detection device that can switch a gas flow path according to a gas flow rate as disclosed in Japanese Patent No. 41300.

That is, as shown in FIG. 6, a gas supply source such as a gas container 1 and a gas intake of an apartment 2 are connected by a gas supply pipe 4, and the gas supply pipe 4 is connected to an automatic switching regulator. Primary pressure regulators 5 and 6 and secondary gas meters 7 which are two-stage primary are provided. In addition, valves and the like (not shown) are also provided, and a gas meter 8 and a valve (not shown) are provided in a pipe for supplying gas from a gas intake to gas consuming equipment of each house of the apartment 2.

[0004] In the gas supply pipe 4b between the pressure regulator 5 on the gas container 1 side, which is a gas supply source, and the parent gas meter 7 for integrating the amount of gas supplied to the entire apartment 2, a parent pressure regulator 6 is provided. The gas supply pipe 4b is further provided with bypass gas passages 14a and 14b for connecting the upstream side and the downstream side of the master pressure regulator 6 in a bypass path. In the bypass gas flow paths 14a and 14b, a child pressure regulator 15 and a microcomputer gas meter 16 installed near a gas supply source as a micro leak detection means are provided in this order from the inlet side.

[0005] The adjustment pressure of the child pressure regulator 15 is set higher than the adjustment pressure of the master pressure regulator 6. Further, the microcomputer gas meter 16 measures the minute flow rate, and determines that a leak has occurred when the flow rate is equal to or more than the threshold value for 30 consecutive days by the minute leak detection function, and turns on an alarm lamp or turns it on. An alarm is issued by alarm means such as sounding of an alarm buzzer.

[0006] In the switching type gas leak detection device having the main part as described above, the gas consumption amount is measured during the middle of the night or during consecutive holidays, that is, during the time when the consumer does not use gas or when going out. Is almost eliminated or the flow rate is 1
In the case of a low flow rate such as less than 50 liter / h, the pressure of the gas supply pipe 4b increases, the master pressure regulator 6 is closed, and the microcomputer gas meter 16
Since the gas flows only to the side, the microcomputer gas meter 1
6 allows monitoring of a minute gas flow rate flowing through the gas supply pipe 4b. In addition, since the gas naturally flows through both the gas supply pipe and the bypass gas flow path in the other time periods when the gas consumption is high, the gas always flows through the bypass gas flow path regardless of the gas consumption. In addition, a minute gas flow rate can be constantly monitored.

At this time, if the gas consumption is completely stopped and no minute gas leakage has occurred, the microcomputer gas meter 16 does not detect the gas flow rate. In other words, in this case, the measurement result of the flow rate of the microcomputer gas meter 16 should be 0.

[0008] Such a state of the so-called zero flow rate is at least 1 for a relatively long period such as 30 days.
If the gas flow rate is continuously detected in the microcomputer gas meter 16 without stopping even once, it goes without saying that the master pressure meter 6 will be used. 1
The micro leak is determined by the micro leak determining means disposed in the inside 6 and the like, and the user or the gas management company is warned to that effect by warning means such as turning on an alarm lamp or sounding an alarm buzzer.

As described above, in the prior art, by installing a minute flow rate measuring device such as a microcomputer gas meter 16 and a bypass pipe for measuring a minute flow rate in a part of a gas supply path, detection of a gas leak at a minute flow rate is performed. I do it.

[0010]

By the way, the above-mentioned conventional gas leak detecting device can surely detect gas leak at a very small flow rate, but it can be used for a long period of time. In this case, there is a possibility that an abnormality such that the original correct pressure adjustment is not performed due to the deterioration of the parent pressure regulator 6 itself or the child pressure regulator 15 itself due to aging or the like, The adjustment pressure difference (differential pressure) between the parent pressure regulator 6 and the child pressure regulator 15 has been confirmed, for example, once a year by field work.

In order to confirm the differential pressure, the child pressure regulator 1
It was necessary to attach a gas stopper with an inspection hole to the outlet on the fifth side, and the inspection work had to be performed using a differential pressure checking device such as a pressure recorder. In this inspection work, first, an inspection hole bolt of a gas stopper with an inspection hole is removed, and a self-recording pressure gauge is connected to the inspection hole. Then, a gas table or the like is connected to one of the terminal closing valves, and one port (flow rate of about 50 to 1) is connected.
(00 l / h) only, and all other end shut-off valves are closed. Then, in this state, the pressure is measured by changing the supply pressure, and the measured pressure is compared to confirm the differential pressure. As described above, the inspection work is complicated, but the inspection work must be performed accurately within a limited time, which has been a factor of increasing the work load of the worker.

Therefore, the present applicant has disclosed in Japanese Patent Laid-Open Publication No.
As disclosed in Japanese Patent No. 316170, a gas leak detection device capable of performing self-diagnosis of abnormal pressure adjustment of the master pressure regulator 6 and the slave pressure regulator 15 has been provided. In this gas leak detection device, the difference between the pressure before and after the shutoff of the shutoff valve is calculated, thereby automatically determining (detecting).
However, when self-diagnosis is performed by the gas leak detection device, the shut-off valve is driven and power is consumed according to the self-diagnosis, so that it has been difficult to frequently perform self-diagnosis. In particular, most of the gas leak detection devices use a lithium battery or the like as a power supply source, so that the power consumption must be reduced.

Accordingly, the present invention has been made in view of the above-described problems,
Adjustment pressure self-diagnosis method capable of self-diagnosis of the adjustment pressures of the master pressure regulator and the slave pressure regulator without stopping the flow rate, and the master pressure regulator and the slave pressure adjustment without driving the shut-off valve It is an object of the present invention to provide a gas leak detection device capable of performing a self-diagnosis of an adjustment pressure of a vessel.

[0014]

According to the first aspect of the present invention, there is provided a method for self-diagnosis of regulated pressure, which is provided by a gas supply source as shown in FIG. A parent pressure regulator 6 provided in a gas supply pipe 4 for conducting gas, and child pressure regulators provided in bypass gas flow paths 14a and 14b for bypassing an upstream side and a downstream side of the parent pressure regulator 6. 15. A self-diagnosis method for self-diagnosis of an adjustment pressure with a parent performance curve and a child performance curve showing a relationship between a gas flow rate and a pressure of the parent pressure regulator 6 and the child pressure regulator 15, respectively. Defining a monitored flow rate section for monitoring a pressure change amount corresponding to a change in the gas flow rate in the bypass gas flow paths 14a and 14b based on the gas flow rate corresponding to the intersection with the curve; Pressure regulation Determining a threshold value corresponding to the pressure change amount in the monitoring flow section when the adjustment pressure of the vessel 6 and the child pressure regulator 15 is normal, and measuring the pressure change amount in the monitoring flow section And, comparing the measured pressure change amount and the threshold value, if the pressure change amount is equal to or more than the threshold value, it is determined that the adjustment pressure is normal, the pressure change amount is less than the threshold value If there is, a step of determining that the adjustment pressure is abnormal, and a step of generating and outputting alarm information for alarming the abnormality of the adjustment pressure in accordance with a result of the determination that the adjustment pressure is abnormal. , Is provided.

According to the self-diagnosis method of the adjusted pressure according to the first aspect of the present invention, based on the gas flow rate corresponding to the intersection of the parent performance curve and the child performance curve, the bypass gas flow path 1
A monitoring flow rate section for monitoring the pressure change amount according to the change in the gas flow rate in 4a and 14b is defined, and a threshold value corresponding to the pressure change amount in the monitoring flow rate section when the adjustment pressure is normal is determined. . Then, when the pressure change amount in the monitoring flow rate section is measured, the pressure change amount is compared with a threshold value, and if the pressure change amount is equal to or greater than the threshold value, it is determined that the adjustment pressure is normal. On the other hand, when the pressure change amount is less than the threshold value, it is determined that the adjustment pressure is abnormal, and alarm information for alarming the abnormality of the adjustment pressure is generated and output.

Accordingly, the pressure of the child performance curve rapidly decreases with an increase in the flow rate, but the parent performance curve does not change significantly in the low flow rate region even if the flow rate increases. Based on the gas flow rate corresponding to the intersection with the curve, a monitoring flow rate section for monitoring the pressure change amount according to the gas flow rate change in the bypass gas flow paths 14a and 14b is defined, and measurement is performed in this monitoring flow rate section. By monitoring the amount of change in the pressure, the self-diagnosis can be made as to whether or not the adjustment pressures of the master pressure regulator 6 and the slave pressure regulator 15 are normal even in the gas flowing state. Also, the pressure is affected by the outside air temperature, but since it is determined based on the amount of pressure change,
An accurate diagnosis can be made. Therefore, the self-diagnosis of the adjustment pressure (differential pressure) of the master pressure regulator 6 and the slave pressure regulator 15 can be performed without stopping the gas supply to the downstream side in the bypass gas flow paths 14a and 14b. In addition, since the alarm information is output according to the detection of the abnormality of the adjustment pressure,
Adjustment of adjustment pressure, replacement of equipment, and the like can be promptly performed.

According to a second aspect of the present invention, there is provided a gas leakage detecting device according to the present invention for solving the above-mentioned problems, as shown in a basic configuration diagram of FIG. 4 is a bypass gas flow path in which a child pressure regulator 15 that bypasses the upstream side and the downstream side of the parent pressure regulator 6 and that is adjusted to a higher closing pressure than the parent pressure regulator is disposed. A gas leak detector that is provided in the bypass gas passages 14a and 14b and that determines that a gas leak has occurred when detecting that a predetermined gas flow rate is continuously flowing in the bypass gas flow paths 14a and 14b for a predetermined time; The bypass defined based on the gas flow rate corresponding to the intersection of the parent performance curve and the child performance curve indicating the relationship between the gas flow rate and the pressure of the parent pressure regulator 6 and the child pressure regulator 15, respectively. Monitoring flow section storage means 22a for storing monitoring flow section information indicating a monitoring flow section for monitoring a pressure change amount according to a change in the gas flow rate in the gas flow paths 14a and 14b; A threshold storage unit 22b that stores a threshold value determined in accordance with the pressure change amount in the monitored flow section when the adjustment pressure of the child pressure regulator 15 is normal; and a monitored flow section information storage unit 22a. A pressure change amount measuring means 21a1 for measuring the pressure change amount in the monitored flow rate section corresponding to the stored monitored flow rate section information; and a storage of the pressure change amount measured by the pressure change amount measuring means 21a1 and the threshold value. Diagnostic means 21a for diagnosing the adjustment pressure based on the result of comparison with the threshold value stored in means 22b
2, and an alarm information output unit 21a3 that generates and outputs alarm information for alarming the abnormality when the diagnosis unit 21a2 diagnoses that the adjustment pressure is abnormal. I do.

According to the gas leak detecting device of the present invention, the gas in the bypass gas flow paths 14a, 14b defined based on the gas flow rate corresponding to the intersection of the parent performance curve and the child performance curve. Monitored flow section information indicating a monitored flow section for monitoring a pressure change amount corresponding to a change in the flow rate is stored in the monitored flow section storage unit 22a. The threshold value determined corresponding to the pressure change amount in the monitoring flow rate section when the adjustment pressure is normal is stored in the threshold value storage unit 22b. The diagnosis unit 21a2 diagnoses the adjustment pressure based on the comparison result between the pressure change amount measured by the pressure change amount measurement unit 21a1 and the threshold value stored in the threshold value storage unit 22b. And diagnostic means 21a
If it is determined in Step 2 that the adjustment pressure is abnormal, alarm information for alarming the abnormality is generated and output by the alarm information output means 21a3.

Therefore, the pressure of the child performance curve sharply decreases with an increase in the flow rate, but the parent performance curve does not change significantly in the low flow rate region even if the flow rate increases. Based on the gas flow rate corresponding to the intersection with the curve, a monitoring flow rate section for monitoring the pressure change amount according to the gas flow rate change in the bypass gas flow paths 14a and 14b is defined, and measurement is performed in this monitoring flow rate section. By monitoring the amount of pressure change, it is possible to perform a self-diagnosis as to whether or not the adjustment pressures of the master pressure regulator 6 and the slave pressure regulator 15 are normal even during the gas leak monitoring. Further, since the self-diagnosis can be performed without stopping the supply of gas to the downstream side, there is no need to drive the shut-off valve in accordance with the self-diagnosis unlike the related art. it can. Further, although the pressure is affected by the outside air temperature, it is determined based on the amount of change in pressure, so that accurate diagnosis can be performed. Therefore, the control pressure (differential pressure) of the master pressure regulator 6 and the slave pressure regulator 15 is maintained without stopping the gas supply to the downstream side in the bypass gas passages 14a and 14b by driving the shutoff valve as in the related art. Can be self-diagnosed. Further, since the alarm information is output in response to the detection of the abnormality of the adjustment pressure, it is possible to quickly adjust the adjustment pressure, replace the device, and the like.

According to a third aspect of the present invention, there is provided a gas leak detecting device as set forth in the second aspect, wherein the threshold value storage means 22b stores the threshold value. The apparatus further includes a threshold updating unit 22a4 that updates the threshold value that has been set based on the pressure change amount measured by the pressure change amount measuring unit 21a1 during a predetermined learning period.

According to the gas leak detection device of the present invention, the threshold value stored in the threshold value storage means 22b is determined by the pressure change amount during a predetermined learning period such as one week or one month. The threshold is updated by the threshold updating unit 22a4 based on the pressure change amount measured by the measuring unit 21a1.
Therefore, the amount of pressure change during the predetermined learning period is learned,
Since the threshold value stored in the threshold value storage means 22b is changed based on the learning result, the self-diagnosis of the adjusted pressure is performed based on the threshold value suitable for the gas supply equipment or the like in which the gas leak detection device is installed. Can be. Therefore, by changing the threshold value based on the learned pressure change amount, the self-diagnosis of the adjusted pressure based on the threshold value suitable for the gas supply equipment or the like in which the gas leak detection device is installed can be performed. Reliability can be improved.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the gas leak detection device according to the present invention is applied to a gas supply facility will be described below.
This will be described with reference to FIGS. In addition, the same reference numerals are given to portions common to the conventional example, and overlapping description will be omitted.

Here, FIG. 2 is a diagram showing a schematic configuration of a part of the gas leak detecting device according to the present invention in the gas supply equipment, and FIG. 3 is a diagram showing gas flow rates of the master pressure regulator and the slave pressure regulator of FIG. 4 is a graph showing a performance curve showing a relationship between pressure and pressure, FIG. 4 is a configuration diagram showing a schematic configuration of the gas leakage detection device of FIG. 2, and FIG. 5 is an example of a self-diagnosis process performed by the CPU of FIG. It is a flowchart which shows.

As shown in FIG. 2, in the gas supply equipment, gas supply pipes 4 for supplying gas to an apartment or the like are provided with primary pressure regulators 5, 6, which are two-stage primary automatic switching regulators, and the like. I have. The bypass gas flow paths 14a and 14b that bypass the upstream side and the downstream side of the master pressure regulator 6 have
A child pressure regulator 15 is provided which is adjusted to a higher closing pressure than the parent pressure regulator 6. Then, the gas leak detection device 20 according to the present invention is provided in the bypass gas flow paths 14a and 14b downstream of the child pressure regulator 15. That is, it is provided in place of the microcomputer gas meter 16 of the gas supply facility described in the related art (see FIG. 6).

The parent pressure regulator 6 and the child pressure regulator 1
The parent performance curve and the child performance curve respectively showing the relationship between the gas flow rate and the pressure of No. 5 are shown in the graph of FIG. FIG.
3A shows a normal time, FIG. 3B shows an abnormal time, and A shows a parent performance curve and B shows a child performance curve. The vertical axis of the graph indicates the pressure [kpa], and the horizontal axis indicates the gas flow rate [liter / h].

In the child performance curve B of the child pressure regulator 15, the pressure is rapidly reduced in the low flow rate region with an increase in the gas flow rate. On the other hand, in the parent performance curve A of the parent pressure regulator 6, even if the gas flow rate increases, a large pressure drop does not occur in a low flow rate region. When adjusting the pressure of the master pressure regulator 6 and the child pressure regulator 15 is normal, to cross the parent performance curves A and child performance curve B at a gas flow rate Q _C as shown in FIG. 3 (a) and Become. However, when the adjustment pressure is abnormal, the parent performance curve A and the child performance curve B do not intersect as shown in FIG.

Therefore, by paying attention to the situation of the pressure drop in the low flow rate region, it is possible to diagnose the adjustment pressures of the master pressure regulator 6 and the slave pressure regulator 15, so that the master performance curve A
Child performance regards the gas flow rate Q _C is less than the gas flow rate range corresponding to the intersection between the curve B and the low flow rate region, the low flow region of the flow rate Q ₀ to Q ₁ with a predetermined interval and monitoring the flow rate interval, the monitoring flow rate The pressure change in the section is monitored.

[0028] In this embodiment, for example, the gas flow rate Q _C corresponding to the intersection of the performance curve 300 l / h]
When the gas flow rate is around 100 to 200 [liter /
h] will be described as a monitoring flow rate section, but the present invention is not limited to this.
The monitoring flow rate range is 0 to 100, 100 to 200, 200 to
A plurality of sections such as 300 [liter / h] may be set as the monitoring flow rate section, and various embodiments may be adopted, such as performing the diagnosis based on the pressure change amount in each section.

Next, the schematic configuration of the gas leak detection device 20 will be described. As shown in FIG. 4, the gas leak detection device 20 has a microcomputer (μCOM) 21 that operates according to a predetermined program. μCO
As is well known, M21 is a central processing unit (CP) that performs various processes and controls according to a predetermined program.
U) 21a, a ROM 21b which is a read-only memory storing programs and the like for the CPU 21a, and a RAM 21c which is a readable and writable memory which stores various data and has an area necessary for processing operations of the CPU 21a. It is composed.

The gas leak detection device 20 is operated by the electric power supplied from the power supply unit 20a.
In the present embodiment, the use of a dry battery enables the use of the gas leak detection device 20 in gas supply equipment that cannot use a commercial power supply.

The μCOM 21 is connected to an electrically erasable / rewritable read-only memory (EEPROM) 22 capable of retaining the stored contents even when the apparatus main body is off. The EEPROM 22 corresponds to a monitored flow section storage unit and a threshold storage unit, and stores various information such as monitored flow section information and threshold information.

The monitored flow section information is normal (FIG. 3 (a)
), The bypass gas flow defined based on the gas flow rate corresponding to the intersection of the parent performance curve A and the child performance curve B showing the relationship between the gas flow rate and the pressure of the parent pressure regulator 6 and the child pressure regulator 15, respectively. 4 shows a monitored flow rate section for monitoring a pressure change amount according to a change in gas flow rate in the paths 14a and 14b. Regarding the parent performance curve A and the child performance curve B, any performance curve such as a performance curve obtained from a design value or a performance curve obtained from an actually measured value may be used.

Further, in this embodiment, in order to indicate the monitored flow rate section, the monitored flow rate section information includes the lower limit flow rate data (flow rate Q ₀ ), the upper limit flow rate data (flow rate Q ₁ ), and the like. . In the present embodiment, the flow rate Q _{0 is set} to 100
[L / h], the flow rate Q ₁ 200 [l / h]
And

Further, the threshold information has a threshold value and the like determined corresponding to the amount of pressure change in the monitoring flow section when the adjustment pressures of the master pressure regulator 6 and the slave pressure regulator 15 are normal. are doing. In addition, as a method of defining the threshold,
A method of determining a threshold value based on a design value or a learning period of, for example, one week or one month after the gas leak detection device 20 is installed, and a threshold value based on an actual measurement value of each individual adjuster during the learning period. Can be used.

The gas leak detecting device 20 further includes a flow rate measuring section 23, a pressure measuring section 24, an alarm section 25, and an interface section 26. And the flow rate measurement unit 2
3. The pressure measurement unit 24 and the alarm unit 25 are connected to the μCOM 21 via the interface unit 26, respectively.

The flow rate measuring unit 23 is provided with the gas supply pipe 4 and the bypass gas flow paths 14a, 14a at predetermined intervals.
4b is a flow rate measuring sensor that measures the flow of gas in 4b,
A flow signal corresponding to the measured flow rate of the gas is converted into a digital signal by the interface unit 26 and input to the μCOM 21.

The flow rate measuring unit 23 is a so-called guessing method (or is also called an estimating method depending on the literature).
A method that measures various fluid physical quantities that change according to the gas flow rate and calculates the flow rate based on the measured value, that is, the dynamic pressure or static pressure due to the gas flow Pressure flow measurement method to measure changes and differential pressure between upstream and downstream of gas flow, area flow measurement method to measure viscous resistance of gas flow, and power rate to move gas turbine blades Turbine flow measurement method to measure, vortex flow measurement method to measure frequency of vortex generated in gas flow, ultrasonic wave to propagate ultrasonic wave to gas flow and measure the propagation time or propagation speed etc. A flow measurement method or the like is particularly suitable.

The pressure measuring section 24 is connected to the bypass gas passage 14
a pressure sensor, such as a semiconductor pressure sensor, for measuring the pressure in the bypass gas flow paths 14a, 14b.
The pressure signal corresponding to the pressure in b
Is converted into a digital signal and input to the μCOM 21.

The alarm unit 25 is an alarm device for detecting that a leak has been detected, or that an abnormality in the adjustment pressure of the master pressure regulator 6 and the child pressure regulator 15 has been detected.
An alarm display corresponding to the alarm signal output from the COM 21 is performed. Note that a display device such as an LED or an LCD can be used as the alarm unit 25, and is implemented by an LED in the present embodiment.

In the present embodiment, a case will be described in which the alarm section 25 performs an alarm display in accordance with alarm information input from the μCOM 21. However, the present invention is not limited to this. The alarm unit 25 can also be realized by various devices such as an alarm device that issues an alarm in conjunction with the device 20 and an NCU (Network Control Unit) that enables communication with a management center that manages gas supply equipment.

The gas leak detection device 20 further includes a μCOM
A shut-off valve drive circuit 28 that outputs a drive signal for driving the shut-off valve 27 in response to a valve close / valve open signal output by 21 is provided. Then, when a drive signal corresponding to the valve closing signal is input, the shutoff valve 27 closes the valve to shut off gas supply to the downstream side of the bypass gas flow paths 14a and 14b.

The RAM 21c has various areas such as a work area and a data storage area during a learning period. The work area stores the measured flow rate Q, the measured pressures P ₀ and P ₁ , a learning period flag which is turned on during the learning period, and turned off when the period ends. Further, in the data storage area during the learning period, data such as the pressure change amount ΔP, the flow rate, and the pressure measured during the period are stored in chronological order.

Next, C of the above-described gas leakage detection device 20
An example of the outline of the self-diagnosis processing performed by the PU 21a will be described below with reference to the flowchart shown in FIG.

The supply of power from the power supply unit 20 causes the CP
When U21a is activated, the self-diagnosis processing shown in FIG. 5 is executed. When the initial processing is executed in step S1, the initial data is stored for each of various areas such as the work area of the RAM 25c and the data storage area during the learning period, and the learning period such as one week or one month elapses. Then, the learning timer that times out is started, the learning period flag is turned on, and the flow rates Q ₀ , Q ₁ and the pressures P ₀ , P ₁ are set to their initial design values, and then the process proceeds to step S2.

In step S2, the flow rate Q is calculated based on the flow rate signal input from the flow rate measuring section 23, and the flow rate Q is stored in the work area of the RAM 21c. Then, in step S3, it is determined whether or not the flow rate Q calculated in the RAM 21c corresponds to the monitored flow rate section indicated in the monitored flow rate section information stored in the EEPROM 22.

It is determined that the flow rate Q is not in the monitoring flow rate section.
If (N in step S3), return to step S2,
It corresponds to the monitoring flow rate section by repeating a series of processing.
Wait for the flow rate Q to be measured. On the other hand, the flow rate Q is the monitored flow rate
If it is determined that it is a section (Y in step S3),
In step S4, the flow rate Q and the
Flow Q₀Is determined to be equal to or not. Flow Q and flow
Q₀Are determined to be equal (in step S4
Y), input from the pressure measuring unit 24 in step S5
Flow rate Q based on the pressure signal₀Pressure P corresponding to₀But
Calculated and this pressure P ₀Is in the work area of RAM 21c
Then, the process proceeds to step S8.

Further, if the flow rate Q and the flow rate Q ₀ is not equal in step S4 (N in step S4), and
In step S6, in order to identify the flow rate Q, whether the flow rate Q and the flow rate Q ₁ is equality. If the flow rate Q and the flow rate Q ₁ is are not equal (step S
6) N), the flow returns to step S2, and a series of processing is repeated to wait for the flow rate Q corresponding to the monitored flow rate section to be measured. On the other hand, if the flow rate Q and the flow rate Q ₁ is found equal (Step S6 Y), the process proceeds to step S7.

[0048] In step S7, the pressure P ₁ which corresponds to the flow rate Q ₁ is calculated based on the pressure signal inputted from the pressure measuring unit 24, the pressure P ₁ is stored in the work area of RAM 21c, thereafter step S8 move on.

In step S8, the pressure change amount ΔP (= P ₀ −) which is the difference between the pressure P ₀ and the pressure P ₁ in the RAM 21c.
P ₁ ) is calculated and stored in the work area of the RAM 21c, and thereafter, the process proceeds to step S9. By this processing, E
Since the pressure change amount ΔP in the monitored flow section corresponding to the monitored flow section information stored in the EPROM (monitored flow section information storage means) 22 is measured, the processing in step S8 is described in claims. It corresponds to a pressure change amount measuring means.

In step S9, whether or not the learning period is in progress is determined based on whether or not the learning timer is in operation. When it is determined that the learning timer is operating, that is, during the learning period (Y in step S9), the process proceeds to step S10. Then, in step S10, the measurement data such as the flow rate and pressure measured this time and the pressure change amount ΔP
Are stored in time series in the data storage area of the RAM 21c during the learning period, and thereafter, the process returns to step S2 to repeat a series of processing. On the other hand, if it is determined in step S9 that the learning timer is not operating, that is, it is not during the learning period (N in step S9), the process proceeds to step S11.

In step S11, it is determined whether the learning period flag of the RAM 21c is OFF. By this determination processing, it is determined whether the learning period has just ended, that is, whether it is necessary to reflect the measurement result of the learning period on the threshold. On the other hand, if the learning period flag is not OFF, that is, if it is necessary to reflect the measurement result on the threshold (N in step S11), step S11 is executed.
Proceed to 12.

In step S12, the average of the plurality of pressure change amounts ΔP stored in the data storage area during the learning period of the RAM 21c is calculated. When a new threshold value is determined based on the calculation result, the threshold value of the EEPROM 22 is determined. The information is updated to the new threshold. Then, step S13
In step, the learning period flag in the RAM 21c is turned off, and thereafter, the process returns to step S2, and a series of processes is repeated.

Therefore, an EEPROM (threshold storage means) 2
Since the threshold value stored in 2 is defined based on the pressure change amount ΔP measured during the predetermined learning period, the process of step S12 corresponds to the threshold value defining means described in the claims.

If it is determined in step S11 that the learning period flag is OFF, that is, it is determined that the updating of the threshold has been completed (Y in step S11), step S14 is performed.
Proceed to. Then, in step S14, the RAM 21
The pressure change amount ΔP of c is compared with a threshold value indicated by the threshold information of the EEPROM 22, and it is determined whether the pressure change amount ΔP is equal to or larger than the threshold value. Therefore, since the diagnosis is made as to whether or not the adjustment pressures of the parent pressure regulator 6 and the child pressure regulator 15 are normal, the determination processing in step S14 corresponds to the diagnosis means described in the claims.

If it is determined that the pressure change amount ΔP is equal to or larger than the threshold value (Y in step S14), it is considered that the adjustment pressures of the master pressure regulator 6 and the slave pressure regulator 15 are normal, and
By returning to step S2 and repeating a series of processes, monitoring of the adjusted pressure is continued. On the other hand, if it is determined that the pressure change amount ΔP is smaller than the threshold value (N in step S14), it is considered that an abnormality has occurred in the adjustment pressures of the master pressure regulator 6 and the slave pressure regulator 15, and then the process proceeds to step S15. move on.

In step S15, the alarm information for making the alarm unit 25 alarm the abnormality of the adjusted pressure is stored in the RAM.
21c, and then proceeds to step S16. Then, in step S16, an alarm signal based on the alarm information is output to the alarm unit 25, and thereafter, the process returns to step S2 and repeats a series of processes to continue monitoring the adjusted pressure. Then, an alarm display corresponding to the alarm signal output from the CPU 21a is performed by the alarm unit 25.

Therefore, if it is diagnosed that the adjustment pressure is not normal, alarm information for alarming the abnormality of the adjustment pressure is generated and output.
And the processing of S16 corresponds to the alarm information output means described in the claims.

As is clear from the above description, the CPU
21a is a pressure change amount measuring means according to the claims,
They function as diagnostic means, alarm information output means, and threshold update means.

Next, a description will be given with reference to an example of the operation (action) of the present embodiment having the above configuration.

[0060] As shown in FIG.
Are installed at the bypass gas flow rates 14a and 14b, and the self-diagnosis processing shown in FIG. 5 is started in response to the start of power supply from the power supply unit 20a. Then, measurement of the flow rate Q is started, and the flow rate monitoring section (100, 200 [liter / liter]) indicated by the flow rate monitoring section information stored in the EEPROM 22 is used.
h]), the pressure P ₀ or the pressure P ₁ corresponding to the flow rate Q is measured. The difference between the pressure P ₀ and the pressure P ₁ is calculated as the pressure change amount [Delta] P (Step S2 to S8).

During the predetermined learning period, the measurement data measured this time and the pressure change ΔP are stored in a time-series manner in the data storage area of the RAM 21c during the learning period (step S1).
0). When the learning period ends, the average of the plurality of pressure change amounts ΔP measured during the learning period is calculated, the threshold information of the EEPROM 22 is updated based on the calculation result (step S12), and the diagnosis of the adjusted pressure starts. Will be done.

Thereafter, when the pressure change amount ΔP is calculated as described above (step S8), the pressure change amount ΔP is compared with the threshold value indicated by the threshold information to diagnose the adjusted pressure. When the pressure change amount ΔP is equal to or larger than the threshold value (Y in step S14), it is determined that the adjustment pressure is normal, and the self-diagnosis is continued. On the other hand, if the pressure change amount ΔP is smaller than the threshold value (N in step S14),
It is determined that the adjustment pressure is abnormal due to at least one of the parent pressure regulator 6 and the child pressure regulator 15, and an alarm display based on the alarm information generated according to the determination result is displayed by the alarm unit. 25 (steps S15 to S16).

As described above, the child performance curve B corresponding to the child pressure regulator 15 has a sharp decrease in pressure as the flow rate increases, but the parent performance curve A corresponding to the parent pressure regulator 6.
Large since the change does not occur, based on the gas flow rate Q _C corresponding to the intersection of the parent performance curve A and a child performance curve B, the bypass gas flow passage 14a is in the low flow rate region increases the flow rate,
Pressure change amount Δ corresponding to change in gas flow rate Q at 14b
By defining a monitoring flow rate section for monitoring P and monitoring the pressure change amount ΔP measured in this monitoring flow rate section,
Even during the gas leak monitoring, the self-diagnosis can be made as to whether or not the adjustment pressures of the master pressure regulator 6 and the slave pressure regulator 15 are normal.

Further, since the self-diagnosis can be performed without stopping the supply of gas to the downstream side, it is not necessary to drive the shut-off valve 27 in accordance with the self-diagnosis unlike the related art. It can be carried out. Further, although the pressure is affected by the outside air temperature, it is determined based on the pressure change amount ΔP, so that accurate diagnosis can be performed.

Accordingly, the master pressure regulator 6 and the child pressure regulator 15 can be operated without stopping the gas supply to the downstream side of the bypass gas passages 14a and 14b by driving the shutoff valve 27.
Self-diagnosis of the adjustment pressure (differential pressure). In addition, since the alarm information is output in response to the detection of the abnormality of the adjustment pressure, it is possible to quickly adjust the adjustment pressure, exchange devices, and the like.

Further, the pressure change amount ΔP during a predetermined learning period is learned, and based on the learning result, an EEPROM is used.
Since the threshold information stored in the (threshold storage unit) 22 is changed, the self-diagnosis of the adjusted pressure can be performed based on a threshold suitable for a gas supply facility or the like in which the gas leak detection device 20 is installed. . Therefore, by changing the threshold value based on the learned pressure change amount ΔP, the gas leak detection device 20
The self-diagnosis of the adjustment pressure based on the threshold suitable for the gas supply equipment or the like in which is installed can be performed, so that the reliability of the diagnosis result can be improved.

In the above-described embodiment, the shutoff valve 27 is not driven. However, during the learning period, the master pressure regulator 6 in the flow rate monitoring section is kept closed with the shutoff valve 27 closed.
Is learned, and when the learning period ends, a threshold value is defined based on the performance curve measured during this period. Various embodiments can be adopted, such as opening the shut-off valve 27 and performing self-diagnosis of the adjustment pressure based on a threshold value.

Further, in the above-described embodiment, the case where the gas leak detection device has a function of performing self-diagnosis of the adjustment pressure of the master pressure regulator 6 and the slave pressure regulator 15 has been described. The present invention is not limited thereto, and may be realized as a device for performing the self-diagnosis.
For example, the shutoff valve 27 and the shutoff valve drive circuit 28 may be omitted from the configuration shown in FIG.

[0069]

As described above, according to the adjusted pressure self-diagnosis method of the present invention described in claim 1, the child performance curve sharply decreases in pressure as the flow rate increases, but the parent performance curve does not. Since a large change does not occur in the low flow rate region even if the flow rate increases, the pressure change according to the gas flow rate change in the bypass gas flow path based on the gas flow rate corresponding to the intersection of the parent performance curve and the child performance curve. By defining a monitoring flow rate section for monitoring the flow rate and monitoring the pressure change measured in this monitoring flow rate section, the adjustment pressure of the master pressure regulator and the slave pressure regulator is normal even when the gas is flowing. Can be self-diagnosed. Although the pressure is affected by the outside air temperature, it is determined based on the amount of pressure change, so that accurate diagnosis can be performed. Therefore, it is possible to perform a self-diagnosis of the adjustment pressure (differential pressure) of the master pressure regulator and the slave pressure regulator without stopping the gas supply to the downstream side in the bypass gas flow path. Further, since the alarm information is output in response to the detection of the abnormality of the adjustment pressure, there is an effect that the adjustment of the adjustment pressure, the replacement of the device, and the like can be promptly performed.

As described above, according to the gas leak detecting device of the present invention, the pressure is rapidly decreased with the increase in the flow rate in the child performance curve, but the flow rate is increased in the parent performance curve. Even in the low flow rate area, no significant change occurs, so the pressure change amount in the bypass gas flow path is monitored based on the gas flow rate corresponding to the intersection of the parent performance curve and the child performance curve. By defining a monitoring flow rate section for monitoring and monitoring the pressure change measured in this monitoring flow rate section, the adjustment pressures of the master pressure regulator and the slave pressure regulator are normal even during gas leakage monitoring. Can be self-diagnosed. Further, since self-diagnosis can be performed without stopping supply of gas to the downstream side, it is not necessary to drive the shut-off valve in accordance with the self-diagnosis as in the related art, so that self-diagnosis can be performed at all times. it can. Further, although the pressure is affected by the outside air temperature, it is determined based on the amount of change in pressure, so that accurate diagnosis can be performed. Therefore, the self-diagnosis of the adjustment pressures (differential pressures) of the parent pressure regulator and the child pressure regulator without stopping the gas supply to the downstream side in the bypass gas passage by driving the shut-off valve as in the related art. This has the effect that it can be performed. Also,
Since the alarm information is output in response to the detection of the abnormality of the adjustment pressure, there is an effect that the adjustment of the adjustment pressure, the replacement of the device, and the like can be promptly performed.

According to the invention described in claim 3, according to claim 2
In addition to the effects of the invention described in the above, since the pressure change amount during the predetermined learning period is learned and the threshold value stored in the threshold value storage means is changed based on the learning result, the gas leakage detection device is installed. The self-diagnosis of the adjusted pressure can be performed based on the threshold value suitable for the gas supply equipment or the like. Therefore,
By changing the threshold based on the learned pressure change,
Since the self-diagnosis of the adjustment pressure based on the threshold suitable for the gas supply equipment or the like in which the gas leak detection device is installed can be performed, it is possible to improve the reliability of the diagnosis result.

[Brief description of the drawings]

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

FIG. 2 is a diagram showing a schematic configuration of a part of a gas leakage detection device according to the present invention in a gas supply facility.

FIG. 3 is a graph showing a performance curve showing a relationship between a gas flow rate and a pressure of a master pressure regulator and a slave pressure regulator of FIG. 2;

FIG. 4 is a configuration diagram illustrating a schematic configuration of the gas leakage detection device of FIG. 2;

FIG. 5 is a flowchart illustrating an example of a self-diagnosis process performed by a CPU in FIG. 4;

FIG. 6 is a diagram showing a schematic configuration of a main part of an entire gas supply system using a microcomputer gas meter incorporating a conventional gas leak detection device.

[Explanation of symbols]

 Reference Signs List 4 gas supply pipe 6 parent pressure regulator 14a, 14b bypass gas flow path 15 child pressure regulator 20 gas leak detection device 21a1 pressure change measurement unit (CPU) 21a2 diagnosis unit (CPU) 21a3 alarm information output unit (CPU) 21a4 Threshold value updating means (CPU) 22a Monitoring flow rate section storing means (EEPROM) 22b Threshold value storing means (EEPROM)

Claims (3)

[Claims] 1. A master pressure regulator provided in a gas supply pipe through which a gas supplied from a gas supply source is passed, and a bypass gas flow path bypassing an upstream side and a downstream side of the master pressure regulator. An adjusted pressure self-diagnosis method for self-diagnosing an adjusted pressure with a set child pressure regulator, wherein a parent performance curve indicating a relationship between a gas flow rate and a pressure of the parent pressure regulator and the child pressure regulator, respectively. Defining a monitoring flow rate section for monitoring a pressure change amount corresponding to a change in the gas flow rate in the bypass gas flow path based on the gas flow rate corresponding to an intersection of the parent performance curve and the parent performance curve; A step of determining a threshold value corresponding to the pressure change amount in the monitoring flow section when the adjustment pressures of the pressure regulator and the child pressure regulator are normal; and measuring the pressure change amount in the monitoring flow section And comparing the measured pressure change amount with the threshold value, and when the pressure change amount is equal to or greater than the threshold value, determines that the adjustment pressure is normal, and the pressure change amount is the threshold value. If it is less than the step of determining that the adjustment pressure is abnormal, and generating and outputting alarm information for alarming the abnormality of the adjustment pressure in accordance with the determination result of the abnormality. Adjusting pressure self-diagnosis method, comprising: 2. A gas supply pipe through which a gas supplied from a gas supply source passes is bypassed between an upstream side and a downstream side of a parent pressure regulator, and is adjusted to a closing pressure higher than the parent pressure regulator. A gas pressure leak is generated when a predetermined gas flow rate is continuously flowed in the bypass gas flow path for a predetermined time in the bypass gas flow path in which the sub-pressure regulator is provided. In the gas leak detection device that determines that, based on the gas flow rate corresponding to the intersection of the parent performance curve and the child performance curve indicating the relationship between the gas flow rate and the pressure of the parent pressure regulator and the child pressure regulator, respectively. Monitoring flow section storage means for storing monitoring flow section information indicating a monitoring flow section for monitoring a pressure change amount according to a change in the gas flow rate in the bypass gas flow path defined by the master pressure; A threshold storage unit that stores a threshold determined in accordance with the pressure change amount in the monitoring flow section when the adjustment pressure of the inflator and the child pressure regulator is normal; and the monitoring flow section information storage means. The pressure change amount measuring means for measuring the pressure change amount in the monitored flow rate section corresponding to the stored monitored flow rate section information, and the pressure change amount measured by the pressure change amount measuring means and the threshold value storage means. Diagnosing means for diagnosing the adjustment pressure based on a comparison result with the stored threshold value, and alarm information for alarming the abnormality when the diagnosing means diagnoses that the adjustment pressure is abnormal. And a warning information output means for generating and outputting a gas leak detection device. 3. The apparatus according to claim 2, further comprising: a threshold updating unit that updates the threshold stored in the threshold storing unit based on the pressure change amount measured by the pressure change amount measuring unit during a predetermined learning period. The gas leak detection device according to claim 2, wherein