JP6340592B2 - Gas shut-off device - Google Patents

Description

  The present invention relates to a gas cutoff device equipped with a three-dimensional acceleration sensor.

  Conventionally, as a seismic sensing means for detecting an earthquake, a three-dimensional acceleration sensor has been used so that an earthquake can be detected normally even if the mounting direction changes. By using a three-dimensional acceleration sensor, installation in any direction is possible, and the work of confirming the installation direction at the time of construction is simplified, and gas shutoff that can be installed in any position and direction of the piping of the flow path An apparatus is disclosed (for example, Patent Document 1).

JP-A-11-94602

  However, the conventional gas shut-off device and gas meter according to Patent Document 1 require a large current consumption to always measure the three-dimensional acceleration, thereby shortening the battery life. was there.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a gas shut-off device with reduced current consumption.

  In order to solve the above-mentioned conventional problems, a means for controlling to measure all directions when the acceleration in one direction is measured and the acceleration exceeds a threshold value, and the measured acceleration in all directions are predetermined. Means is provided for outputting a blocking signal when the condition is satisfied.

  By using the gas cutoff device of the present invention, it is possible to measure the flow rate equipped with a three-dimensional acceleration sensor with reduced current consumption.

The block diagram of the gas meter in Embodiment 1-5 of this invention Schematic configuration diagram of the ultrasonic flow measurement unit The flowchart which shows the operation | movement procedure of the acceleration determination of the gas meter in Embodiment 1 of this invention. The flowchart which shows the operation | movement procedure of the acceleration determination of the gas meter in Embodiment 2 of this invention. The flowchart which shows the operation | movement procedure of the acceleration determination of the gas meter in Embodiment 3 of this invention. The flowchart which shows the operation | movement procedure of the acceleration determination of the gas meter in Embodiment 4 of this invention. The flowchart which shows the operation | movement procedure of the acceleration determination of the gas meter in Embodiment 5 of this invention.

(Embodiment 1)
A gas meter will be described as a gas cutoff device in the first embodiment of the present invention. FIG. 1 is a block diagram of a gas meter according to a first embodiment of the present invention.

  In FIG. 1, a gas meter 1 is provided in the middle of a gas supply pipe a, and one or more gas appliances installed in each customer's house are connected to a downstream pipe.

  In FIG. 1, the gas meter 1 includes a blocking unit 2, a flow rate measuring unit 3, a calculation unit 4, an acceleration measurement control unit 5, an acceleration measurement unit 6, an acceleration measurement result holding unit 7, an acceleration threshold value storage unit 8, an acceleration determination unit 9, A state holding unit 10 is included.

  The flow rate measuring unit 3 is connected in the path of the gas supply pipe a and, as will be described later, obtains a propagation time difference caused by the gas flow in the gas supply pipe a using an ultrasonic signal, and detects an instantaneous gas flow rate. Is.

  The calculation unit 4 calculates the gas flow rate by integrating the instantaneous flow rate based on the instantaneous flow rate detected by the flow rate measurement unit 3. The flow rate measurement unit 3 and the calculation unit 4 realize the function of the flow rate measurement unit.

  The acceleration measurement control unit 5 controls the acceleration measurement unit 6 at regular time intervals. The acceleration measurement control unit 6 determines the direction in which the acceleration is measured, the cycle for measuring the acceleration, the resolution for measuring the acceleration, and the acceleration measurement instruction to the acceleration measurement unit 6. It is something to do.

  The acceleration measuring unit 6 is controlled by the acceleration measurement control unit 5 to measure acceleration, and includes a first acceleration detecting unit 11 that measures acceleration in the first horizontal direction and a second acceleration that measures acceleration in the second horizontal direction. An acceleration detection unit 12 and a vertical acceleration detection unit 13 that measures acceleration in the vertical direction are provided, and the magnitude of acceleration in each direction is output to the acceleration measurement result holding unit 7.

  The acceleration measurement result holding unit 7 holds the result of the measured acceleration for a certain period. The holding period may be a setting that can be changed.

  The acceleration threshold value storage unit 8 stores acceleration threshold values of components in each direction in order to make an earthquake determination. In addition, the threshold value of each component may be a setting that can be changed depending on the environment such as installation conditions.

  The acceleration determination unit 9 determines whether or not the measured acceleration exceeds the acceleration threshold value stored in the acceleration threshold value storage unit 8.

  The state holding unit 10 represents the current state of the gas meter 1.

  Here, the calculation unit 4, the acceleration measurement control unit 5, the acceleration measurement result holding unit 7, the acceleration threshold value storage unit 8, the acceleration determination unit 9, and the state holding unit 10 are a processor and an operation program that constitute a microcomputer (microcomputer) or the like. Each function is realized by executing a predetermined operation program in a processor and performing corresponding processing.

  In addition, although the flow rate measurement unit 3 in the first embodiment uses ultrasonic measurement means, other flow measurement methods may be used in a short cycle such as a fluidic method as a measurement method. Other methods may be used as long as continuous measurement is possible.

The shut-off unit 2 is connected in the path of the gas supply pipe a, and shuts off the gas supply by closing the gas supply pipe a based on an instruction from the acceleration determination unit 9.

  The operation of the flow rate measurement unit 3 and the calculation unit 4 will be described using an ultrasonic method as an example, but the invention is not limited to this method as described above.

  FIG. 2 is a schematic configuration diagram of the flow rate measuring unit 3. The flow rate measuring unit 3 includes a measurement flow path 30 having a rectangular cross section communicating with the gas supply pipe a, and a pair of ultrasonic waves is provided on the upstream side and the downstream side of the flow path walls facing each other. Transceivers 31 and 32 are arranged. These ultrasonic transmitters / receivers 31 and 32 are set so that the ultrasonic propagation path obliquely crosses the gas flow flowing through the measurement flow path 30, and the ultrasonic waves are alternately transmitted / received, so that the ultrasonic flow is sequentially transmitted and received. Propagation of ultrasonic waves in the opposite direction.

  At this time, the distance between the ultrasonic transceivers 31 and 32, that is, the measurement distance is L, the angle of the ultrasonic propagation path with respect to the gas flow is φ, and the ultrasonic propagation time from the upstream to the downstream of the ultrasonic transceivers 31 and 32 is If t1, the ultrasonic propagation time from downstream to upstream is t2, and the sound velocity is C, the flow velocity V can be obtained by the following equation.

V = L / 2 cos ((1/1/1)-(1 / t2))
The instantaneous flow rate of the gas flow is calculated from the flow velocity V and the cross-sectional area of the measurement channel 30. The time interval for measuring the instantaneous flow rate can be set within a range where ultrasonic waves can be transmitted and received.

  In general, since the time to change the gas flow rate varies depending on the gas appliance used, depending on the start-up and control, reducing the measurement time interval is advantageous for instantaneous instrument discrimination, but the measurement time interval Is shortened, the battery consumption increases in a gas meter or the like driven by the battery. Further, when the measurement time interval is a two-digit order interval equivalent to the membrane type used in the conventional gas meter, it becomes difficult to judge by looking at the difference in flow rate change.

  In this embodiment, when the gas appliance is not used, the periodic instantaneous flow rate is measured at intervals of 2 seconds and the difference value is taken to determine the activation of the gas appliance. Note that the measurement time interval can be further shortened. For example, after starting the gas appliance, control such as shortening the measurement time interval may be performed in order to increase measurement accuracy.

  Next, the operation of the acceleration determination unit 9 will be described in detail below. In this embodiment, the current consumption is reduced by measuring one direction at a time instead of always measuring in all three dimensions, and battery consumption can be suppressed. When making an earthquake determination, if a predetermined value is exceeded by measurement in each direction, all three-dimensional directions are measured to make an earthquake determination.

  3 shows an acceleration measurement control unit 5, an acceleration measurement unit 6, an acceleration measurement result holding unit 7, an acceleration threshold value storage unit 8, an acceleration determination unit 9, a first acceleration detection unit 11, and a second acceleration detection unit in the present embodiment. 12 is a flowchart showing an operation procedure of the vertical acceleration detector 13. These store programs for executing the control flow from step S1 to step S11 shown in FIG.

  In step S1, the measurement direction is set, and the process proceeds to step S2. In step S2, it is determined whether or not it is the timing of the measurement cycle. If it is the measurement timing, the process proceeds to step S3, and in step S3, the acceleration a1 in the set measurement direction is measured.

  As for the setting of the first measurement direction, for example, the direction with the highest numerical value from past earthquake data may be set as the initial direction.

  In step S4, the measured acceleration a1 is output and the output result is held. In step S5, it is determined whether or not the held acceleration a1 is greater than or equal to a predetermined value A. If the acceleration a1 is greater than or equal to the predetermined value A, the process proceeds to step S7. When the acceleration a1 is less than the predetermined value A, the process proceeds to step S6. In step S6, a direction different from the previous measurement direction is set, and the process proceeds to step S2. For example, when the first direction is measured, the second direction is measured next, and when the second direction is measured, the vertical direction is measured next, so that the direction different from the previous direction is measured. To do.

  In step S7, the measurement direction is set to measure all three dimensions, and in step S8, accelerations ax, ay, and az in all three dimensions are measured. In step S9, the measured accelerations ax, ay, and az are output and held, and the process proceeds to step S10.

  In step S10, it is determined whether or not the measured accelerations ax, ay, and az satisfy a predetermined condition M. When the accelerations ax, ay, and az do not satisfy the predetermined condition M, the process proceeds to step S6. When the accelerations ax, ay, and az satisfy the predetermined condition M, it is determined that an earthquake has occurred, and the process proceeds to step S11 to perform a shutoff output, and the gas supply pipe is closed to shut off the gas supply.

  Thus, the acceleration determination unit 9 measures and determines the acceleration in all three-dimensional directions when the acceleration in one direction exceeds the threshold value.

  As described above, in the present embodiment, by suppressing the measurement in the three-dimensional direction to a minimum, current consumption can be reduced and battery consumption can be suppressed.

  For the predetermined condition M, for example, an initial condition reflecting the experiment result of the manufacturer is set. However, if, for example, an earthquake that should normally shut off gas does not occur, the conditions at the time of the earthquake may be stored and added to the condition M.

(Embodiment 2)
A gas shut-off device according to the second embodiment of the present invention will be described using a gas meter.

  FIG. 4 is a flowchart showing an operation procedure of acceleration determination in the present embodiment. In FIG. 4, the same number is attached | subjected to the procedure which shows the same operation | movement as FIG. 3, and description is abbreviate | omitted.

In FIG. 1, the impact value storage unit 14 is configured to store a variation pattern of acceleration due to a lightning strike or an external impact. Moreover, the acceleration determination part 9 stores the program which performs the control flow of step S1 to step S21 shown in FIG.
The difference from the first embodiment is that an impact value storage unit 14 is provided. In the case where the acceleration variation pattern stored in the impact value storage unit 14 is similar to the measured acceleration variation pattern, the measured acceleration is Judgment is not acceleration due to an earthquake, but acceleration due to lightning strikes or external impacts, preventing false interruptions due to seismic interruption.

  That is, the exceptional condition of the predetermined condition in the first embodiment is set, and the gas is not shut off when the acceleration measurement result corresponds to the exceptional condition.

  Next, the operation of the above configuration will be described, but the point at which acceleration is measured by the acceleration measuring unit 6 is the same as that of the first embodiment, and will be omitted.

In the flowchart shown in FIG. 4, in step S21, the acceleration a1 held for a predetermined period is collected, and it is determined whether or not the acceleration variation pattern matches the impact value variation pattern. If the acceleration is not an impact value variation pattern, the process proceeds to step S5. If the acceleration is an impact value variation pattern, the process proceeds to step S6.
As described above, the acceleration determination unit 9 is configured not to perform an earthquake determination when the measured acceleration is determined to be an impact value.

  As described above, in the present embodiment, not only reducing current consumption and suppressing battery consumption, but also being able to determine an impact value, it is possible to determine an earthquake that excludes lightning and vibration due to external impact. it can.

(Embodiment 3)
A gas shut-off device according to the third embodiment of the present invention will be described using a gas meter.

  FIG. 5 is a flowchart showing an operation procedure of acceleration determination in the present embodiment. In FIG. 5, the same number is attached | subjected to the procedure which shows the same operation | movement as FIG. 3, and description is abbreviate | omitted.

  In FIG. 1, the acceleration measurement control unit 5 is configured to output so as to change the acceleration detection cycle when the flow rate is detected by the calculation unit 4. Moreover, the acceleration determination part 9 stores the program which performs the control flow of step S1 to step S31 shown in FIG.

  The difference from the first embodiment is that the acceleration measurement control unit 5 changes the acceleration detection cycle when the flow rate is detected. When the flow rate is detected, the earthquake determination is performed in a short cycle. To improve earthquake detection accuracy.

  Next, the operation of the above configuration will be described, but the point at which acceleration is measured by the acceleration measuring unit 6 is the same as that of the first embodiment, and will be omitted.

In the flowchart shown in FIG. 5, it is determined in step S31 whether or not there is a flow rate. When there is no flow rate, the process proceeds to step S2 and it is determined whether or not it is a measurement timing. If there is a flow rate, the process proceeds to step S3, and acceleration is measured.
Thus, when there is a flow rate, the acceleration determination unit 9 shortens the measurement cycle and increases the earthquake determination accuracy.

  As described above, this embodiment not only reduces current consumption and suppresses battery consumption, but also determines the accuracy of earthquakes when there is a flow by determining the presence or absence of flow and changing the measurement cycle. The safety function can be improved.

(Embodiment 4)
A gas shutoff device according to a fourth embodiment of the present invention will be described using a gas meter.

  FIG. 6 is a flowchart showing an operation procedure of acceleration determination in the present embodiment. In FIG. 6, the same number is attached | subjected to the procedure which shows the same operation | movement as FIG. 3, and description is abbreviate | omitted.

In FIG. 1, the immediate cutoff value storage unit 15 is configured to store a predetermined value for immediate cutoff in each direction component. Moreover, the acceleration determination part 9 stores the program which performs the control flow of step S1 to step S41 shown in FIG.

  The difference from the first embodiment is that an immediate cutoff value storage unit 15 is provided. When the measured acceleration exceeds the cutoff value stored in the immediate cutoff value storage unit 15, three-dimensional measurement is performed. It is judged as an earthquake without performing it, and it is immediately shut off to improve safety.

  Next, the operation of the above configuration will be described, but the point at which acceleration is measured by the acceleration measuring unit 6 is the same as that of the first embodiment, and will be omitted.

  In the flowchart shown in FIG. 6, in step S41, it is determined whether or not the measured acceleration a1 exceeds the immediate cutoff value B. When the measured acceleration a1 is equal to or greater than the immediate cutoff value B, the process proceeds to step S11 and is immediately interrupted. When the measured acceleration a1 is less than the immediate cutoff value B, the process proceeds to step S5, and it is determined whether or not the measured acceleration a1 is equal to or greater than the predetermined value A.

  As described above, when the measured acceleration exceeds the cutoff value immediately, the acceleration determination unit 9 determines that it is an earthquake and immediately outputs the cutoff without performing three-dimensional measurement.

  As described above, according to the present embodiment, not only reducing current consumption and suppressing battery consumption, but also being able to determine whether or not to immediately shut down can speed up earthquake detection and improve safety functions. .

(Embodiment 5)
A gas shutoff device according to a fifth embodiment of the present invention will be described using a gas meter.

  FIG. 7 is a flowchart showing an operation procedure of acceleration determination in the present embodiment. In FIG. 7, the same reference numerals are given to the procedures showing the same operations as those in FIG.

In FIG. 1, the state holding unit 10 is a configuration that represents the current state of the gas meter 1. Moreover, the acceleration determination part 9 stores the program which performs the control flow of step S1 to step S51 shown in FIG.
Note that the difference from the first embodiment is that a state holding unit 10 is provided, and when the current state of the gas meter 1 is a predetermined state, the safety is improved by always performing three-dimensional measurement.

Examples of the predetermined state include a period when there is a high possibility that an aftershock will occur after a large earthquake, and a period when the shut-off state is released and return leakage is confirmed. During this period, safety can be improved by always performing three-dimensional measurement as a predetermined state.
Next, the operation of the above configuration will be described, but the point at which acceleration is measured by the acceleration measuring unit 6 is the same as that of the first embodiment, and will be omitted.

In the flowchart shown in FIG. 7, it is determined in step S51 whether or not the gas meter is currently in a predetermined state. If the state is not the predetermined state, the process proceeds to step S2. In the predetermined state, the process proceeds to step S7, and the acceleration measurement direction is set to all directions.
As described above, the acceleration determination unit 9 always performs three-dimensional acceleration measurement when the gas meter is in a predetermined state.

  As described above, according to the present embodiment, not only the consumption current is reduced and the battery consumption is suppressed, but also the three-dimensional acceleration measurement is always performed in a predetermined state, thereby speeding up the detection of the earthquake and ensuring the safety. Function can be improved.

  In the above embodiment, acceleration detection in three directions has been described. Of course, the detection is not limited to three directions, but the accuracy is inferior to three directions, but may be performed in two directions.

  As described above, the gas shut-off device according to the present invention can be applied as a seismic shut-off system with reduced current consumption because it measures acceleration in the three-dimensional direction only when it is necessary to minimize acceleration measurement.

DESCRIPTION OF SYMBOLS 1 Gas meter 2 Blocking part 3 Flow measurement part 4 Calculation part 5 Acceleration measurement control part 6 Acceleration measurement part 7 Acceleration measurement result holding part 8 Acceleration threshold value memory | storage part 9 Acceleration judgment part 10 State holding part 11 1st acceleration detection part 12 2nd acceleration Detection unit 13 Vertical acceleration detection unit 14 Impact value storage unit 15 Immediate cutoff value storage unit

Claims (4)

Acceleration measuring means capable of measuring acceleration in two or three directions;
An impact value storage unit storing acceleration fluctuation patterns due to lightning strikes and external impacts;
When acceleration in one direction measured at predetermined intervals by the acceleration measuring means is input, the variation pattern of the acceleration does not match the variation pattern stored in the impact storage unit, and the acceleration exceeds a threshold value Is an acceleration measurement control means for controlling the acceleration measurement means so as to detect the acceleration in another one or two directions,
A gas shut-off device comprising shut-off means for shutting off the gas when the measured acceleration in two or three directions satisfies a predetermined condition. When detecting the flow rate of the gas, serial mounting of the gas cutoff apparatus in claim 1, characterized in that to reduce the predetermined interval. The gas cutoff device according to claim 1 or 2, wherein when the measured acceleration in one direction is not less than a predetermined value, the gas is shut off without measuring the acceleration in the other direction. The gas cutoff device according to any one of claims 1 to 3 , wherein acceleration in all of two or three directions is always detected during a predetermined state.

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