JP2972800B2 - Gas shut-off device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a gas appliance such as a bath, an oven or a water heater, in which gas is continuously supplied to the gas appliance, and the gas appliance is used continuously beyond the safe use time of the gas appliance. In this case, that is, the present invention relates to a gas shut-off device that shuts off gas supply as dangerous when a gas appliance is forgotten to be turned off.

[0002]

2. Description of the Related Art Conventionally, a household gas shut-off device obtains a gas flow value at regular intervals, and when this gas flow value changes, it is determined that a gas appliance is newly used or stopped. The appliance is determined, and the safe use time of each gas appliance registered in advance is monitored. When the use time exceeds the safe use time, the supply of gas is cut off as dangerous.

[0003]

In such a conventional gas shut-off device, the gas appliance is determined only by a change in the flow rate value and the safe use time is monitored. Therefore, there is a problem that a malfunction may occur.

[0004] The present invention has been made in view of the above points, and has as its object to provide a highly reliable gas shut-off device with improved discrimination accuracy of gas appliances.

[0005]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, the gas shut-off device of the present invention provides a flow sensor that outputs a pulse signal corresponding to the flow rate of the supplied gas, and a fuzzy inference using the flow data obtained from the output of the flow sensor as an input. An inference unit that determines a gas appliance that is being used, a control unit that outputs a gas cutoff signal when the determined use time of the gas appliance exceeds a safe use time corresponding to the gas appliance, and the gas A shut-off unit for shutting off gas supply in response to the shut-off signal.

[0007]

According to the above configuration, the gas appliance used is determined by performing fuzzy inference with the flow data obtained from the output of the flow sensor as an input, so that the accuracy of determining the gas appliance is improved. become.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention. A gas shut-off device 1 of this embodiment includes a flow sensor 2 for outputting a pulse signal corresponding to a flow rate of a supplied gas.
And an inference unit 3 for fuzzy inference using flow rate data described later obtained from the output of the flow rate sensor 2 as an input to determine a gas appliance being used, and a use time of the determined gas appliance, The control unit 4 that outputs a gas shutoff signal when the safe use time corresponding to the appliance is exceeded.
And a shutoff section 5 for shutting off gas supply in response to a gas shutoff signal.

In the conventional gas shut-off device, the gas appliance is determined from the change in the flow rate value. However, in the present invention, the flow rate data obtained from the output pulse of the flow rate sensor 2, in this embodiment, corresponds to the flow rate value. The gas appliance is determined by performing fuzzy inference with the number of pulses per fixed measurement time and the number of pulse period changes per measurement time as inputs.

That is, FIG. 2A shows a membership function of the number of pulses per measurement time corresponding to a flow rate which is an input variable of fuzzy inference in the inference unit 3, and VS
(Very little), S (less), MS (slightly less), M (normal), MB (slightly more), B (more), V
B (very many), and FIG. 2B shows a membership function of the number of periodic changes of the pulse per measurement time, which is also an input variable of the fuzzy inference in the inference unit 3. It has three labels: VS (very little), S (less), and B (more).

On the other hand, as shown in FIG. 3, the output variables are the eight labels of a complicated gas appliance by a stove pilot, a stove, a stove, an oven, a water heater, a bath pilot, a bath fully open, and PID control. Has a corresponding membership function.

The inference unit 3 performs fuzzy inference according to the following fuzzy rules.

IF pulse number = VB THEN Bath fully open IF pulse number = B THEN Bath fire IF pulse number = MB THEN water heater IF pulse number = M THEN oven IF pulse number = MS THEN stove IF pulse number = S THEN stove IF pulse Number = VS THEN stove top IF pulse number = VS THEN gas leak IF frequency change = VS THEN gas leak IF frequency change = S THEN bath IF frequency change = S THEN water heater IF frequency change = S THEN Oven IF Number of cycle changes = S THEN Stove IF Number of cycle changes = S THEN Stove IF Number of cycle changes = B THEN Complex gas appliance In the inference unit 3, when there is a change in the flow rate, or
As in the conventional example, the number of pulses and the number of pulse period changes are extracted from the output pulses from the flow rate sensor 2 at regular time intervals, and these are used as inputs, and the corresponding rules of the fuzzy rules are used for each label. The fitness of the input variable is calculated, and the calculated fitness is taken as the fitness of the membership function of the corresponding output variable label, and the output variable label with the highest fitness is used as the gas appliance used. This is to determine (the maximum height method).

As described above, the flow rate data obtained from the output pulse of the flow rate sensor 2, that is, the number of pulses per measurement time and the number of pulse period changes per measurement time corresponding to the flow rate are input and fuzzy inference is performed. Since the used gas appliance is determined, it is possible to perform the determination with higher accuracy than in the conventional example.

When the gas appliance is determined by the inference unit 3 in this manner, the control unit 4 stores in advance the use time of the determined gas appliance corresponding to the gas appliance based on the discrimination output. It is monitored whether or not the safe use time is exceeded. If the safe use time is exceeded, it is determined that the gas appliance has been forgotten to be turned off or abnormal, and a shutoff signal is output. The gas supply is shut off in response to the signal.

FIG. 4 is a flowchart of the above processing. First, an output pulse from the flow rate sensor 2 is fetched (S1), and flow rate data extracted from the output pulse, that is, a pulse per measurement time corresponding to the flow rate is obtained. By using the number and the number of pulse cycle changes per measurement time as inputs, fuzzy inference is performed to determine the gas appliance being used (S2), and monitor the usage time of the determined gas appliance (S3). It is determined whether or not the safe use time of the gas appliance has been exceeded (S4), and if it has been exceeded, a cutoff signal is output (S5).

FIG. 5 is a block diagram of another embodiment of the present invention, and portions corresponding to the above-described embodiment are denoted by the same reference numerals.

The gas cutoff apparatus 1 ₁ of this embodiment, by fuzzy inference data at a time corresponding to the aforementioned flow data and flow data as input is intended to determine the gas appliance, and thus, the inference section 3 ₁ is supplied with the output pulse from the flow sensor 2 and the time data from the timer 6. That is, in this embodiment, considering that the time period during which the gas appliance is used is determined to some extent from the life pattern, the time at which the gas appliance is used is added to the input of the fuzzy inference to determine the gas appliance. Is what you do.

[0020] FIG. 6 shows a membership function of time, which is the input variables of the fuzzy inference in the inference unit 3 _1, M
It has three labels (morning), D (day), and N (night). Membership function of the number of the inference unit 3 _one period changes the input variables per pulse number and measurement time per measuring time corresponding to a flow rate value pulses of the fuzzy inference in the embodiment described above shown in FIG. 2 cases Is the same as

On the other hand, as shown in FIG. 7, the output variables have three labels of bath, stove, and fan heater and corresponding membership functions.

[0022] Then, the inference unit 3 ₁ performs fuzzy inference by the following such fuzzy rules.

IF pulse number = VB AND time = N THEN bath IF pulse number = MS AND time = M THEN stove IF pulse number = MS AND time = N THEN stove IF pulse number = M AND number of cycle changes = B THEN fan the heater inference unit 3 _1, extracts the number of pulses and the period change than the output pulses from the flow sensor 2, along with an input them, corresponding among the fuzzy rules the time at that time as an input rule In, the fitness of the input variable of each label is calculated, and the smallest value is selected as the fitness of the input variable for each rule (MIN operation). The selected fitness is regarded as the fitness of the membership function value of the corresponding output variable label, and the output variable label having the highest fitness is determined as the gas appliance used (maximum height). Method).

The processing after the gas appliance used in this way is determined is the same as in the above-described embodiment.

[0025]

As described above, according to the present invention, the used gas appliance is determined by fuzzy inference using the flow rate data obtained from the output of the flow rate sensor as an input. As a result, the accuracy of discriminating the gas appliance is improved.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a diagram illustrating a membership function of an input variable in an inference unit in FIG. 1;

FIG. 3 is a diagram illustrating a membership function of an output variable in the inference unit in FIG. 1;

FIG. 4 is a flowchart for explaining the operation.

FIG. 5 is a block diagram of another embodiment of the present invention.

FIG. 6 is a diagram illustrating a membership function of an input variable in the inference unit in FIG. 5;

FIG. 7 is a diagram showing membership functions of output variables in the inference unit of FIG. 5;

[Explanation of symbols]

1,1 ₁ Gas shut-off device 2 Flow rate sensor 3,3 ₁ Inference unit 4 Control unit 5 Shut-off unit

Claims (2)

(57) [Claims] A flow sensor for outputting a pulse signal corresponding to a flow rate of a supplied gas, and a flow rate data obtained from an output of the flow rate sensor as an input to carry out fuzzy inference to determine a gas appliance used. An inference unit for determining, a control unit for outputting a gas cutoff signal when the use time of the determined gas appliance exceeds a safe use time corresponding to the gas appliance, and a gas responding to the gas cutoff signal. A gas shut-off device comprising: a shut-off unit for shutting off supply. 2. The inference unit, in addition to the flow rate data,
2. The gas shut-off device according to claim 1, wherein fuzzy inference is performed by using a time corresponding to the flow rate data as an input.