JPH0325023Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is designed to prevent incomplete combustion due to lack of oxygen, poor combustion due to clogging of heat exchanger fins, clogging of exhaust pipes, etc. in gas combustors of gas water heaters. In the early stages of abnormal combustion, when incomplete combustion has not yet been reached, the system warns the user of the occurrence of an abnormality without shutting off the gas, and when the user takes action, normal combustion returns to normal combustion. This invention relates to a safety device for a gas combustor that takes double safety measures by immediately shutting off the gas to ensure safety if dangerous abnormal combustion occurs without countermeasures taken by the user.

[Conventional technology]

As a conventional technology, for example,
As shown in Publication No. 148550, a heat sensor such as a normally open bimetal switch is installed at the position where the temperature rise is greatest when the inner shell or other fins of the water heater become clogged, and Equipped with alarms such as lamps and buzzers at the position of the value on the front of the outer body,
By connecting the alarm to a power source such as a dry battery via a heat sensor, the user is notified of fin clogging before incomplete combustion occurs, and accidents such as carbon monoxide poisoning caused by incomplete combustion can be prevented. or as shown in Japanese Utility Model Application Publication No. 57-19754,
When a pair of thermocouples are connected with opposite polarities and incomplete combustion occurs, a voltage change in the pair of thermocouples closes an electromagnetic safety valve to ensure safety.
As shown in Japanese Utility Model Application Publication No. 55-51466, a cold junction of a thermocouple is installed in a part of the appliance that receives the combustion heat of the main burner to make the operation of the electromagnetic safety valve sensitive only during combustion of the main burner. There is something.

[The problem that the idea attempts to solve]

However, the conventional technology described above either warns of fin clogging before it leads to incomplete combustion, or detects incomplete combustion and shuts off the gas. Since the gas supply is stopped at the early stage of abnormal combustion, which is not yet dangerous, a re-ignition operation is required even when the cause of the abnormality can be easily removed, making it extremely inconvenient and inconvenient in actual use.

Therefore, this idea focuses on the deformation of the combustion flame when incomplete combustion occurs due to lack of oxygen, or poor combustion occurs due to clogged heat exchanger fins or clogged exhaust pipes.
The initial flame of abnormal combustion and the abnormal combustion flame can be detected separately, and at the initial stage of abnormal combustion, when incomplete combustion has not yet been reached, the system notifies and warns the user of the occurrence of an abnormality without shutting off the gas. However, if the user takes action, normal combustion will return to normal combustion and the product can continue to be used; however, if the user does not take action and leaves the product as it is, or if the warning of the abnormality is unattended and cannot be noticed. is a gas combustion method that eliminates the above-mentioned drawbacks of conventional methods by taking dual safety measures by immediately shutting off the gas to ensure safety when the abnormal phenomenon reaches a dangerous abnormal combustion state. This provides a safety device for the equipment.

[Means to solve the problem]

A pair of thermocouples connected with opposite polarity at a position where abnormal combustion flame a caused by incomplete combustion due to lack of oxygen in the main burner 4 or poor combustion due to clogging of the heat exchanger 6 in a gas water heater etc. can be detected. A, B
The abnormal combustion flame a is detected by detecting changes in the voltage of the pair of thermocouples A and B, and a gas safety valve is controlled to open and close using a solenoid valve installed in the gas passage to the main burner 4. A heat detection sensor 1 such as a normally open bimetal switch is provided at a position where the circuit C can detect the initial flame b of the abnormal combustion flame a, and the abnormal combustion initial flame b is detected by the heat detection sensor. , and a warning circuit D that operates alarm devices 2 and 3 such as a buzzer and a lamp before the safety circuit C is activated.

[Effect]

In the above configuration, when incomplete combustion due to oxygen deficiency or combustion failure due to clogging of heat exchanger fins or exhaust pipe occurs, an abnormality occurs in the main gas burner 4 at the initial stage of abnormal combustion when incomplete combustion has not yet been reached. The heat detection sensor 1 detects the initial combustion flame b and activates alarms 2 and 3 such as a buzzer and a lamp to notify and warn the user. That is, the system notifies the user of the occurrence of an abnormality without shutting off the gas and prompts the user to take action. Therefore, if the user takes measures such as opening the window to ventilate the air in the room or removing the dish towel that was accidentally placed over the exhaust port, the abnormal combustion condition will be resolved and the It is possible to transition to normal combustion and continue using it. Alarm devices such as buzzers and lamps 2,
If the notification to the user in accordance with 3 is ignored and left unattended, or if the warning of the occurrence of an abnormality is not known because no one is present, the abnormal condition may gradually progress to a dangerous abnormal combustion state. When the abnormal combustion flame a of the main burner 4 is connected to a pair of thermocouples A and B
etc. detect this and close the gas safety valve installed in the gas passage to the main burner 4 to cut off the gas and ensure safety.

〔Example〕

An embodiment of the safety device for a gas combustor according to this invention will be described below with reference to the drawings.

The embodiment shown in the drawing is an example applied to a gas water heater, and C is a safety circuit in which a pair of thermocouples A and B are connected so that their thermoelectromotive forces have opposite polarities, and when one thermocouple is The thermocouple A is placed in front of the normal combustion flame c of the main burner 4, and the other thermocouple B is installed inside the inner shell 5 so as to touch only the abnormal combustion flame a of the main burner 4.
In addition, the electromagnet M of a gas safety valve such as a solenoid valve is connected via a safety fuse F, and abnormal combustion flame a of gas is detected by voltage changes of thermocouples A and B to control the opening and closing of the gas safety valve. ing. Further, D is a warning circuit, which is an example in which a so-called quick-start ignition circuit is incorporated and its power supply is also used. The heat detection sensor 1 is installed so that the abnormal combustion initial flame b comes into contact with it, and alarms 2 and 3 such as buzzers and lamps are connected to the power supply E through the heat detection sensor 1 and installed independently of the quick ignition circuit. When abnormal combustion initial flame b is detected by
3 is activated. In addition, E is a power source such as a dry battery, C is a capacitor, and S is a changeover switch that is linked to the ignition control knob. When not in use, connect to the power source to form a charging circuit, and when in use, connect to the thermocouple side. to form a discharge circuit,
These make up the quick-fire ignition circuit. 6
7 is a fin-and-tube type heat exchanger provided at the upper part of the inner shell 5, and 7 is a gas nozzle that supplies gas to the main burner 4.

When the changeover switch S is switched to the thermocouple side in conjunction with the ignition control knob during use (see the dotted line in Figure 2), the current pre-charged in the capacitor C is discharged, and the electromagnet M of the gas safety valve is
is excited to hold the gas safety valve open, the main burner 4 is ignited and burned, and after a certain period of time, the electromagnet of the gas safety valve is activated by the thermoelectromotive force generated when the thermocouple A is heated by the combustion flame of the main burner 4. M is excited and the gas safety valve is kept open even after the discharge current from capacitor C disappears. Next, when the use is stopped, the changeover switch S is linked with the ignition control knob.
is switched to the power supply side (see solid line in Figure 2)
A charging circuit is formed and the capacitor C is charged to the required amount by the power source E in preparation for the next use.

Therefore, during the above-mentioned use, when incomplete combustion due to lack of oxygen or poor combustion due to clogging of the fins of the heat exchanger 6, clogging of the exhaust pipe, etc. occurs, the stage in the initial stage of abnormal combustion that has not yet reached incomplete combustion etc. In this case, the abnormal combustion initial flame b extending upward from the normal combustion flame c of the main burner 4 heats the heat detection sensor 1 such as a normally open bimetal switch, so the heat detection sensor 1 detects this and turns on. Current from the power supply E flows through alarm devices 2 and 3 such as buzzers and lamps, activating the alarm devices 2 and 3, and notifying the user of the occurrence of an abnormality with the buzzer and lamp, prompting the user to take measures such as eliminating the cause of the abnormality. .

At this time, in the abnormal combustion initial flame B, only the heat detection sensor 1 is heated and the thermocouple B is not heated, so the combined thermoelectromotive force of the pair of thermocouples A and B is at the separation level.
The voltage does not drop to V ₀ , and the electromagnet M continues to keep the gas safety valve open and the gas is not shut off (see Figure 3). Therefore, in response to the above warning, the user opens the window to ventilate the indoor air, removes the clogged fins of the heat exchanger 6, or removes the cloth, cloth, etc. that has been accidentally hung over the exhaust port. If the cause of the abnormality is quickly dealt with, the main burner 4 returns to the normal combustion flame c, and the heat detection sensor 1 is no longer heated by the abnormal combustion initial flame b, so that the alarms 2 and 3 are also stopped. The combined thermoelectromotive force generated by the pair of thermocouples A and B also returns during normal combustion (see Figure 3).

Next, if the user does not notice or ignores the warning of the occurrence of abnormality in the early stage of abnormal combustion, or if the user is unattended, the abnormal condition will progress further and reach a dangerous abnormal combustion condition, and the main burner 4 will be turned off. The combustion flame further extends upward to form an abnormal combustion flame a, which heats the other thermocouple B, so the thermoelectromotive forces of the pair of thermocouples A and B cancel each other out, resulting in their synthesis. Thermal electromotive force is at breakaway level
When V ₀ drops below 0, the gas safety valve is released from being held open by the electromagnet M and is closed, thereby cutting off the gas and extinguishing the combustion in the main burner 4 (see Figure 3).
During this time, the heat detection sensor 1 continues to be heated by both abnormal flames a and b, so the alarms 2 and 3 continue to operate, and their operation stops at the same time as the main burner 4 is extinguished.

[Effect of idea]

As explained above, this device provides a warning without shutting off the gas in the early stages of abnormal combustion, which is not yet dangerous, when an abnormality occurs such as incomplete combustion due to lack of oxygen or poor combustion due to clogging of heat exchanger fins. When the user takes action, normal combustion returns to normal combustion, and if the user does not take action and a dangerous abnormal state occurs, the gas is immediately shut off to ensure safety. Since it takes serious safety measures, it is extremely easy to use in actual use, and the safety level is doubled, so even the elderly and children can use it safely.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a safety device for a gas combustor according to this invention, FIG. 2 is a circuit diagram, and FIG. 3 is a graph showing the operation of the safety circuit. a... Abnormal combustion flame, A, B... Thermocouple, C...
Safety circuit, b... Abnormal combustion initial flame, 1... Sensor, 2, 3... Alarm, D... Warning circuit.

Claims (1)

[Scope of utility model registration request] A pair of thermocouples A and B connected with opposite polarity are installed at a position where abnormal combustion flame a of gas can be detected, and the gas safety valve is shut off when abnormal combustion flame a is detected by the pair of thermocouples A and B. A safety circuit C is provided, and a sensor 1 is provided at a position where abnormal combustion initial flame b can be detected separately from the abnormal combustion flame detection position, and when the abnormal combustion initial flame b is detected by the sensor 1, the safety circuit A safety device for a gas combustor, which includes a warning circuit D that activates alarms 2 and 3 such as a buzzer and a lamp before the activation of the warning circuit D.