JPS59189213A - Safety device of burner - Google Patents

Abstract

PURPOSE:To improve safety of a burner, by a method wherein existence of disorders of a flame detecting circuit and a control circuit are detected even during combustion and the combustion is suspended at the time of the disorder. CONSTITUTION:Although electrification to a gas valve 2 is interrupted by disappearing valve opening output of the gas valve 2 when a flame detecting circuit 4 and a control circuit 5 are normal through opening of a switch 7, the valve opening output is sent to the gas valve 2 again from the control circuit 5, therefore, a gas burner 1 is kept burning as a switch 7 is returned instantly and a flame detector 3 and the flame detecting circuit 4 are connected again with each other. Then when the valve opening output is applied to the gas valve 2 from the control circuit 5 at the time of opening of the switch 7, a gas valve 8 for closure and suspension is made to close and fuel supply to the gas burner 1 is made to interrupt by deciding that the flame detecting circuit 4 and the control circuit 5 are in disorder by a check circuit 6.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a safety device for a combustor that uses gas or oil as fuel.

In conventional combustion appliances, the release of 11N of extinguishing phase fuel is prevented.
In order to achieve this, the fuel valve is closed when the gas burner (1) is extinguished, and its configuration is shown in FIG.

( ) is a gas burner, (2) is a gas valve, (3) is a flame detector, (4) is a flame detection circuit, and (5) is a control 11 circuit that controls opening and closing of the gas valve (2). In this configuration, when the flame detector (3) detects that the gas burner (1) is extinguished, the flame detection circuit (4) sends an extinguishing signal to the control circuit (5), and this extinguishing signal activates the control circuit (5). Then close the gas valve (2) and stop combustion of the gas burner (1).

y The control device for this type of combustor is required to have a "fail-safe" function that safely controls the combustor in the event of a failure in each circuit.For this reason, conventional devices have, for example, a flame detection circuit (4),
Check whether the control circuit (5) is working properly or not by checking the gas burner (1).
) is equipped with a fuel pre-check mechanism to inspect before combustion. However, although the conventional control device d can perform a combustion check, it cannot check each circuit during combustion. In order to ensure safety due to circuit failure during combustion, if more than a certain amount of fuel is being burned, the combustor will easily blow out and this will not be a problem, but in order to control the load temperature to the set temperature, In proportional control type heaters and heaters that control the amount of combustion according to the deviation, when the deviation becomes small, the amount of combustion may be extremely reduced, and in this case, the stability of combustion becomes considerably low and the engine blows out. I don't think it's easy for this to occur. Therefore, even if it blows out or survives, if the flame detection circuit (4) etc. is malfunctioning, raw fuel will not be released and an extremely dangerous situation will occur.

The present invention aims to solve the problems of the prior art, and will be specifically explained below based on an embodiment shown in the drawings.

(1) is a gas bar, (2) is a gas valve, (3) is a flame detector, (4) is a flame detection circuit, and (5) is a control circuit. (
6) is a check circuit that operates while the gas burner (1) is burning, (7) is a switch, and (8) is a closing gas valve.

The check circuit (0) opens the switch (7) for a very short period of time (for example, 02 seconds) at fixed time intervals (for example, 10 seconds), and receives the output of the control circuit (5) through the circuit (9). When the gas valve (2) has an open output, the closing gas valve (8) is closed to cut off the fuel supply.

The above-mentioned gas valve (2) is equipped with a dash-bottom function, so that when electricity is cut off, the valve is gradually closed, and when electricity is applied, the valve is opened at the spacer. The reason for this is when the flame detection circuit (4) etc. are normal.

This is to ensure that the valve does not close completely when checked.
Such a method is limited to the fourth embodiment and includes, for example, interposing a single tank between the gas valve (2) and the gas burner (1), or interposing the gas valve (1) from the control circuit (5) to the gas burner (1). 2)
A timer circuit may be provided in the circuit up to to electrically delay only the valve closing operation, and furthermore, when checking the check circuit (6), a separate circuit 11 is used. = regas valve (2)
The valve may be held in an open state.

The present invention has the following second configuration, in which the switch (7) is opened for a very short time at regular intervals during the combustion of the gasper (1). When the switch (7) is opened, if the flame detection circuit (4) and control circuit (5) are normal, the valve opening output to the gas valve (2) disappears and the communication to the gas valve (2) is cut off. However, the switch (7) returns instantly and the flame detector (3) and flame detection circuit (4) are connected again, so the valve opening output is sent from the control circuit (5) to the waste valve (2) again. and therefore the gas burner (
1) continues to burn.

And when the switch (7) mentioned above is opened, the control circuit (
If the opening output is sent from 5) to the gas valve (2), the check circuit (6) determines that the flame detection circuit (4) and control circuit (5) are abnormal and closes the closing gas valve (8). The valve is closed to cut off the supply of combustion to the gas burner (1).

As explained above, according to the present invention, the presence or absence of an abnormality in the flame detection circuit and the control circuit 111 is detected even during combustion, and combustion is stopped in the event of an abnormality. The safety of the combustor can be dramatically improved by using it alone or in combination with the Blicheck mechanism, which is a provision for the control device of this type of combustor.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a control device showing a conventional example, and FIG. 2 is a block diagram of a control device showing an embodiment of the present invention. (2)...Gas valve (3)...Flame detector (4)
... Flame detection circuit (5) ... rb (J control circuit (6)
... Check circuit patent applicant Kenji Noritz Co., Ltd. Representative Toshibe Ota

Claims (1)

[Claims] A flame detector, a flame detection circuit connected to the flame detector, a control circuit that controls the opening and closing of the fuel valve based on signals from the flame detection circuit, and a control circuit that shuts off and controls the flame detector and the flame detection circuit at fixed intervals during combustion. A safety device for a combustor, comprising a check circuit that receives an output from the circuit and operates to cut off fuel supply when the output is the opening output of the fuel valve.