JP2817342B2 - Gas shut-off device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention automatically shuts off a gas passage when an abnormality occurs, and prevents gas explosion and poisoning accidents caused by city gas, propane gas, etc. before they occur. It concerns the device.

2. Description of the Related Art As shown in FIG. 5, a conventional gas shut-off device of this type includes a gas meter 2 in one gas supply line and a flow rate measuring means 3 for emitting a signal in accordance with the amount of gas passing through the gas meter 2. And a shutoff means 4 for stopping the supply of gas.
The control unit 5 determines the gas use state of each gas appliance 6 based on the flow rate signal from the flow rate measurement unit 3 and determines that the gas appliance 6 is out of the proper use condition, and issues a cutoff signal to the cutoff unit 4.

FIG. 6 shows an example of the configuration of this conventional control unit 5. Components having the same numbers as those in FIG. 5 are components having the same functions.
The control unit 5 receives the flow rate signal Fp from the flow rate measuring means 3 and shuts off the gas flow path when, for example, the gas amount passing through the gas meter has flowed for a predetermined time with a constant value. Based on the flow rate signal Fp from the flow rate measuring means 3, the calculation unit 7 calculates and outputs the supply heat value Qu per unit time.
At the same time, the presence / absence of a temporal change in the supply heat value Qu is determined, and when it is determined that the gas appliance is newly turned on, the output C is output. Further, a timing signal TB for time measurement is output. The calorific value Qu from the arithmetic unit 7 is separated into the calorific value Qui for each gas appliance each time the output C is output, and is input to the classification determination unit 8. The category determination unit 8 determines which category of the determined calorific value Qui belongs to which calorific value category, and outputs the result Si. Safety duration Ti
(I = 1, n) is set in advance, for example, as shown in the following table.

The duration determination unit 9 determines the determination result of the heat generation amount determination unit 8.
Based on Si, the time Ti corresponding to the judgment category is set from among the safety continuation times provided for each category, and the time since the calorific value Qui is supplied using the clock signal TB from the calculation unit 7 is integrated. This is set as T and compared with the previously set safety time T position. If T ≧ Ti, the cutoff signal V is output to the cutoff means 4. If T <Ti, the heating value Qu supplied from Qui to Quj
, This change is recognized by the arithmetic unit 7 and the signal C is output. The continuation time determination unit 9 calculates the integration time based on the signal C.
The Tr was reset to zero and a new integration was started. However, in the above-described configuration, the division is determined only based on the total gas amount flowing in the gas supply line or information on a change in the flow amount. (1) When multiple gas appliances are started to be used at the same time,
It mistakenly recognizes that one gas appliance has begun to be used, and makes a mistake in shutoff determination.

(2) When the total gas amount decreases, it is not possible to specify whether the use of one gas appliance or the use of multiple gas appliances has ended, and therefore it is not known which segment of the duration timer should be stopped.

(3) Even if a single gas appliance is used, if the supply calorific value Qu changes due to automatic flow control or manual operation of the appliance itself,
The user mistakenly recognizes that a new gas appliance has begun to be used or has finished using the gas appliance, and makes a mistake in the cutoff determination.

And so on.

The present invention solves such a conventional problem, and specifies a currently used gas appliance, and accurately determines to which of the calorific value categories the heat value of each gas device belongs by dividing the heat value into a plurality in advance. The purpose of the determination is to prevent erroneous recognition.

Means for Solving the Problems To solve the above problems, the gas shut-off device of the present invention is
By providing individual signal receiving means for receiving an individual signal sent from each gas appliance connected to the gas supply line, a flow signal from the flow measuring unit is separated for each gas appliance used. Further, a configuration is provided in which a calculation unit calculates a supply heat value per unit time for each gas appliance used and outputs the calculated calorific value to the classification determination unit.

Effect of the Invention The present invention makes it possible to obtain a supply heat value per unit time for unit determination for each gas appliance for the classification judgment by the above-described configuration. Can be specified. In addition, even if a change in flow rate accompanied by a change in classification is observed during the use of one gas appliance, it is possible to cope without erroneous recognition.

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a block diagram of the present invention, and those having the same numbers as those in FIG. 5 are components having the same functions. In addition to the conventional example, an individual signal transmitting / receiving means 10 capable of receiving an individual signal sent from each gas appliance is newly provided.
FIG. 2 shows the overall system configuration. The individual signal transmitting / receiving means 10 is a home bus 11 comprising a twisted pair cable.
Are also connected to each gas appliance 6. FIG. 3 shows a circuit configuration of the individual signal transmitting / receiving means 10. It is also assumed that a circuit configuration transparent to the individual signal transmitting / receiving means 10 is provided in each gas appliance 6. Logic 1 in data transmission
, Both Q2s are turned off during one bit transmission time. When transmitting a logical 0, Q2 of the transmission data a and b is alternately turned on in the first half of transmission of one bit, and both Q2 are turned off in the second half, thereby obtaining an AMI code (negative logic / duty) as shown in FIG. 50%). As a communication control method, n: n communication is enabled by detecting collision by CSMA / CD. That is, transmission and reception can be performed individually with each gas appliance.

For example, if an existing gas appliance is turned on and begins to be used, at the same time, the gas appliance sends a packet of an on-state notification signal to which information such as the ID number of the gas appliance, the type of the appliance, and whether there is an abnormality is added. Transmit to gas shut-off device.
In this gas shut-off device, this information is received by the individual signal transmitting / receiving means 10 and further transmitted to the arithmetic unit 7 to output C, whereby the increased flow rate statement of the flow rate signal Fp from the flow rate measuring means 3 is registered as a new gas appliance flow rate. I do. The arithmetic unit 7 outputs a time signal TB for time measurement and a flow signal Fp from the flow measuring means 3.
The calorific value Qu supplied per unit time is divided into calorific values Qui for each gas appliance based on the above, and the calculated calorific value Qui is input to the classification determination unit 8.
The category determination unit 8 determines whether the measured calorific value Qu position belongs to any of the calorific value categories, and outputs a result Si.

The duration determination unit 9 determines the determination result of the heat generation amount determination unit 8.
Based on Si, the time Ti corresponding to the judgment category is set from among the safety continuation times provided for each category, and the time since the calorific value Qui is supplied using the clock signal TB from the calculation unit 7 is integrated. This is defined as T, and is compared with the previously set safety time Ti. If T ≧ Ti, the cutoff signal V is output to the cutoff means 4. If an off-state notification signal is received from the gas appliance when T <Ti, the content is transmitted to the arithmetic unit 7 via the individual transmission / reception means 10. The off-state notification signal stops the clock signal TB and outputs the signal C. The duration determination unit 8 returns the integration time Tr to zero based on the signal C, and stops the integration.

Alternatively, when the flow rate change notification signal is received from the gas appliance in use when T <Ti, the duration determination unit 8 outputs the signal C
As a result, the integration time Tr is reset to zero and a new integration is started.

By providing individual transmitting and receiving means in the above configuration, any data can be transmitted between each gas appliance and this gas shut-off device, so that the number, type, flow rate, and continuous use time of currently used gas appliances can be individually grasped. This has the effect of making it possible to achieve more detailed safety management.

In this embodiment, a wired twisted pair cable is used as an information transmission medium for connecting each gas appliance and the present gas shut-off device. However, the same effect can be obtained by using wireless, ultrasonic waves, light, or the like. Also, a change in the gas flow pattern in the gas supply line may be replaced with a signal.

Effects of the Invention As described above, the following effects are obtained according to the gas shut-off device of the present invention.

(1) Since the on / off state notification signal from each gas appliance is obtained along with the change in the gas flow rate, it is possible to completely grasp whether the flow rate has changed in the same appliance, whether the appliance has been turned on / off, or whether it is a single appliance or a plurality of appliances. There is an effect of realizing the cutoff determination.

(2) The present gas shut-off device can collectively manage the status of all connected gas appliances, so that various services can be easily developed by connecting to an external communication network, for example.
For example, emergency notification when an abnormality or failure occurs in an appliance, and a fee system for each gas appliance used are established. It also facilitates interlocking with other home HA systems.

(3) Furthermore, even though no gas appliances are turned on,
When the gas flow is flowing, a new safety function can be added, such as immediately judging that raw gas is leaking and shutting off even if the flow is very small.

[Brief description of the drawings]

FIG. 1 is a block diagram of a gas shut-off device according to an embodiment of the present invention, FIG. 2 is an overall system configuration diagram using the same,
FIG. 3 is a circuit diagram of the individual signal transmission / reception means of the device, FIG. 4 is a waveform diagram of an AMI code output from the individual transmission / reception means of the device, and FIG. 5 is an overall system configuration diagram using a conventional gas shut-off device. FIG. 6 is a block diagram of a conventional gas shut-off device. 1 ... gas supply line, 3 ... flow rate measuring means, 4 ... cutoff means, 5 ... control unit, 7 ... calculation unit, 8 ... sort judgment unit, 9 ... continuous time judgment unit, 10 ... Individual transmission / reception means.

Continuation of front page (72) Inventor Hiroo Iwabuchi 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. (58) Field surveyed (Int. Cl. ⁶ , DB name) G01F 3/22

Claims (1)

(57) [Claims] 1. A flow rate measuring means installed in a gas meter for detecting an amount of gas passing through the gas meter and outputting an electric signal;
A calculation unit for calculating a calorific value per unit time of the gas meter passing gas amount; an individual signal receiving unit for receiving an individual signal transmitted from a gas appliance connected to a gas supply line; the calculation unit and the individual unit A duration determining unit connected to the signal receiving unit, separating the calorific value for each used gas appliance by a signal from the individual signal receiving unit, and measuring a duration from when gas for each of the used gas appliances starts flowing; and Gas shut-off device provided with.