JP2000213742A - Gas security equipment - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To reduce the size and to improve the discrimination ability of a gas use pattern. SOLUTION: An ultrasonic sensor 1 for measuring a flow rate of a gas flowing in a flow path 2, a pressure sensor 5 for measuring a gas pressure in the gas flow path, and detecting that an earthquake of a predetermined seismic intensity or more has occurred. And a control circuit 4 for judging whether the gas can be used safely based on signals from the three types of sensors, and a shutoff valve for shutting off the gas when the control circuit 4 judges that the gas is abnormal. 7 and a drive circuit 6 for driving the shut-off valve 7
It is provided with.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention measures a gas flow rate and shuts off a gas passage when an abnormal flow rate is measured.
The present invention relates to a gas safety device for ensuring safety in using gas.

[0002]

2. Description of the Related Art In recent years, when a gas meter for measuring the amount of gas used has measured a large amount of flow or has been used for an unusually long time, it is determined that an abnormality has occurred and the gas passage is determined. The one with a built-in security device that shuts off and ensures safety is widely used.

[0003] In this type of flow rate measuring system for a gas safety device, a membrane type meter for measuring a flow rate from a volume passing through the meter within a predetermined time is generally used. In FIG. 6, normally, when gas is used, the gas flows to the membrane type flow rate measuring unit 14 of the meter, and a signal is transmitted to the control circuit 4 every time a certain volume flows. Based on this signal, the integrated flow rate of the gas is calculated, and it is determined whether the gas flow pattern is abnormal. If it is determined that the gas flow pattern is abnormal, a shut-off signal is output to the shut-off valve driving circuit 6 and the shut-off valve 7 is shut off. Turn off the gas. Further, as a security function, when an earthquake of a predetermined seismic intensity or higher occurs, a function of detecting a shaking by the seismic sensor 8 and shutting off the shutoff valve 7 and a warning by detecting an abnormal gas pressure by the pressure sensor 5 are issued. Out, shut-off valve 6
It has a function to shut off.

[0004]

However, with the recent diversification of construction circumstances, the installation conditions of the gas security device have also diversified, and there has been a problem that demand for miniaturization has increased. In addition, as the types of gas appliances have increased and the usage patterns of gases have diversified, conventional gas safety devices can measure only the integrated flow rate, so there is a limit to the detection of gas usage patterns for determining abnormal gas flow rates. There was a problem that was.

[0005]

According to the present invention, an ultrasonic sensor smaller in size than a conventional film-type measuring unit is used for a flow measuring unit. As a result, the size of the gas security device can be reduced, and the instantaneous flow rate can be measured by an ultrasonic sensor to detect various gas usage patterns.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The first aspect of the present invention realizes downsizing of a gas safety device by adopting a flow rate measuring method using an ultrasonic sensor in a flow rate measuring section.

The invention according to claim 2 adopts a flow rate measuring method using an ultrasonic sensor in a flow rate measuring section,
Further, a liquid crystal is used for the integrated flow rate display.

According to a third aspect of the present invention, there is provided a memory IC for recording the integrated flow rate so that the integrated flow rate can be stored even if the gas safety device itself fails.

According to a fourth aspect of the present invention, a reading circuit and a connector are provided so that the value of the integrated flow rate recorded in the memory IC can be easily read.

[0010] The fifth aspect of the present invention is to expand the degree of freedom when installing the gas safety device by allowing the gas inlet and outlet to be freely switched.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a configuration diagram showing a gas safety apparatus according to Embodiment 1 of the present invention. The basic configuration is the same as that of the description of the conventional example. The difference between the present embodiment and the conventional example is that the ultrasonic sensor 1 and the flow path 2 having a clear sectional area are used as the flow rate measuring unit instead of the conventional membrane measuring unit. That is, the ultrasonic sensor driving circuit 3 is provided. The size of the ultrasonic sensor 1 and the flow path 2 can be realized with a volume that is 1/3 or less of that of the conventional membrane type measuring unit. In this embodiment, a signal is sent to the ultrasonic sensor driving circuit 3 at predetermined time intervals in order to measure the gas flow rate,
The velocity of the gas flowing in the flow path 2 is determined by the ultrasonic sensor 1,
The instantaneous flow rate is measured from the gas velocity and the cross-sectional area of the flow path. Further, similarly to the conventional gas safety device, the pressure sensor 5, the shut-off valve 7, and the seismic sensor 8 are provided to secure the safety of the gas use environment.

(Embodiment 2) FIG. 2 is a configuration diagram showing a gas safety apparatus according to Embodiment 2 of the present invention. The basic configuration is the same as that of the description of the conventional example. The difference between the present embodiment and the conventional example is that the ultrasonic sensor 1 and the flow path 2 having a clear sectional area are used as the flow rate measuring unit instead of the conventional membrane measuring unit. An ultrasonic sensor drive circuit 3 is provided, and a liquid crystal is used for integrated flow rate display. The description of the measurement unit is the same as that of the first embodiment. Further, the conventional display unit mechanically rotates the gears on which the numbers are displayed by using the movement of the film-type measuring unit, but in the present embodiment, the display from the liquid crystal 9 is performed by a signal from the control circuit 4. As a result, the size of the gas security device can be reduced.

(Embodiment 3) FIG. 3 is a configuration diagram showing a gas safety apparatus according to Embodiment 3 of the present invention. The basic configuration is the same as that described in the second embodiment, and the feature of this embodiment is that a recording memory 10 for recording the integrated flow rate at predetermined time intervals is provided. In this embodiment, EEPRO is used as a recording memory.
Since the liquid crystal 9 and the control circuit 4 break down, the integrated flow cannot be displayed, or even if the gas safety device does not operate due to a power supply failure, the integrated flow until the failure can be stored. ing.

(Embodiment 4) FIG. 4 is a block diagram showing a gas safety apparatus according to Embodiment 4 of the present invention. The basic configuration is the same as that described in the third embodiment. The feature of the present embodiment is that the integrated flow rate reading circuit 1
1 and a connector 12 for connecting an external readout device. Thus, the contents of the recording memory can be checked without disassembling the gas security device, so that the contents of the recording memory can be read not only at the time of failure of the gas security device but also at the time of normal maintenance and inspection.

(Embodiment 5) FIG. 5 is a block diagram showing a gas safety apparatus according to Embodiment 5 of the present invention. The basic configuration is the same as that described in the fourth embodiment, and the feature of this embodiment is that a measurement direction switching unit 13 is provided. In the case of the measurement method using the ultrasonic sensor 1, even if the direction of the gas flowing through the flow path 2 is reversed, the flow rate can be measured by reversing the sign of the flow velocity of the gas to be measured. By setting the measurement direction by the measurement direction switching means 13, it is possible to install the gas safety device so that the gas flows in the opposite direction.

[0017]

As is apparent from the above description, the gas safety device according to the present invention has the following effects.

Since the flow rate measuring section is smaller than that of the conventional gas security device, the gas security device can be downsized. Also,
Since the instantaneous flow rate can be measured, it is possible to accurately determine a gas usage pattern that was difficult to determine with a conventional gas safety device, thereby improving safety in gas usage.

In addition to the above effects, the integrated flow rate display is smaller than the conventional gear display, so that the gas safety device can be further downsized.

In addition to the above effects, the reliability of the gas security device can be improved because the gas usage is preserved when the gas security device fails.

In addition to the effects described above, since the contents of the recording memory can be easily checked, the reliability of the gas security device can be further improved by checking the contents and operation of the recording memory during maintenance and inspection.

In addition to the above-described effects, since the measurement can be performed even when the gas flow direction is reversed, the gas safety device can be easily installed without regard to the gas flow direction.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating a gas security device according to a first embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a gas safety device according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram illustrating a gas security device according to a third embodiment of the present invention.

FIG. 4 is a configuration diagram illustrating a gas security device according to a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram illustrating a gas security device according to a fifth embodiment of the present invention.

FIG. 6 is a configuration diagram showing a conventional gas safety device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrasonic sensor 2 Flow path 3 Ultrasonic sensor drive circuit 4 Control circuit 5 Pressure sensor 6 Shutoff valve drive circuit 7 Shutoff valve 8 Seismic sensor 9 Liquid crystal 10 Recording memory 11 Integrated flow readout circuit 12 Connector 13 Measurement direction switching means

Continuing on the front page (72) Inventor Takao Tokunan 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd.

Claims (5)

[Claims] 1. A flow path for flowing a gas, an ultrasonic sensor for measuring a flow rate of the gas flowing through the flow path, a pressure sensor for measuring a gas pressure in the gas flow path, and a predetermined seismic intensity or more. A seismic sensor that senses that an earthquake has occurred, a control circuit that determines whether gas can be used safely based on signals from the three types of sensors, and a control circuit that determines that an abnormality has occurred. A gas safety device comprising a shutoff valve for shutting off gas and a drive circuit for driving the shutoff valve. 2. The gas security device according to claim 1, further comprising a display unit for displaying a gas usage amount, wherein the display unit uses a liquid crystal. 3. The gas safety device according to claim 1, further comprising a recording memory for recording the integrated flow rate. 4. The gas safety device according to claim 3, further comprising a reading circuit for reading data from the recording memory from outside, and a connector for connecting the integrated flow reading device. 5. The gas safety device according to claim 1, further comprising a measurement direction switching means for enabling a flow rate to be measured even when the flow of the gas is reversed.