JPH0717941Y2 - Ignition and flame detection device in burner - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to an ignition / combustion flame detection device in a burner in which ignition and flame detection of a burner are performed by a common electrode.

(Prior Art) As a conventional technology, there is, for example, Japanese Patent Laid-Open No. 62-50726.

This publication has a common contact, two sets of interlocking switching contacts having first and second contacts, an ignition power supply and an ignition detection power supply, and the common contact and the second contact at the time of ignition. And the input side of the ignition detector are short-circuited with the formation of an ignition circuit, and when the ignition is detected, the common contact and the first contact are conducted to release the short-circuit on the input side of the ignition detector for detection. An ignition and ignition detection device is disclosed which is configured to form an ignition detection circuit by a power supply.

(Problems to be solved by the invention) In the above device, when the ignition state is automatically switched to the flame detection state, it is necessary to incorporate a sequence for this switching in the ignition detector, which is expensive, and the transformer There is a problem that the contact cannot be switched when the power is on.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to suppress the wear of the switching contact when switching from ignition to flame detection and to avoid the adverse effect of high voltage on the detection circuit.

(Means for Solving the Problems) In the ignition / combustion flame detection device of the present invention, the burner body, the ignition electrode, and the high-voltage side contact of the transformer are connected to the ignition circuit. A high-voltage relay is provided, and a second high-voltage relay that opens and closes the detection circuit is provided in a detection circuit to which the burner body, the ignition electrode, and a flame detector that detects the presence or absence of flame are connected. The low voltage circuit connected to the low voltage side contact of
A first timer for setting an ignition time from when the high voltage relay is turned on to close the ignition circuit to when the first high voltage relay is turned off to open the ignition circuit; and after the ignition time has elapsed It has a configuration in which a second timer that sets the second high voltage relay to ON to set a time point at which the detection circuit is closed is connected.

(Operation) The first high voltage relay with high rated voltage and withstands high voltage,
When the ignition circuit and the detection circuit are opened and closed by the second high-voltage relay and the ignition contact is turned on, a high voltage is applied to the ignition electrode of the ignition circuit 7 to ignite the burner, and at the same time, the first After starting the operation of the timer and the second timer, and after the ignition time set by the first timer has elapsed, the first high-voltage relay is turned off to open the ignition circuit, and the second timer causes the ignition time to be opened. After the set delay time has elapsed, the second high voltage relay is turned on to close the detection circuit, and flame detection is performed between the ignition circuit being opened and the detection circuit being closed. There is a time lag to eliminate the effect of high voltage on the equipment.

(Effects of the Invention) Since the present invention is configured as described above, it is possible to eliminate the problem that the switching contact on the high voltage side is damaged by the high voltage and malfunctions, and to perform switching between ignition and flame detection stably and accurately. You can

Further, it is possible to eliminate the adverse effect of the high voltage on the flame detector and prevent the malfunction of the flame detector due to the high voltage.

(Embodiment) Next, an embodiment of the present invention will be described with reference to the drawings.

An ignition and flame detection device provided for performing ignition of a burner and flame detection by a common power source, an AC power source 1,
The low-voltage circuit 3 that connects the low-voltage side contact 2a of the high-voltage generating transformer 2 incorporates an ignition contact 4 that is turned on and off by a manual operation to open and close the low-voltage circuit 3.

Further, the low-voltage side contact 2a of the transformer 2 has an ignition contact 4
A normally-closed contact 14 is connected to open and close the low-voltage circuit 3 when turned on.

The ignition circuit 7 to which the high-voltage side contact 2b of the transformer 2, the burner body 5, and the ignition electrode 6 having the frame rod 6a for igniting the burner is connected has a normally open contact sealed in vacuum. However, the first high voltage relay 8 having a high rated working voltage (9 KV in this example) is incorporated, and the normally open contact of the first high voltage relay 8 is connected between the high voltage side contact 2b of the transformer 2 and the ignition electrode 6. ing. When the normally open contact of the first high voltage relay 8 is turned on and the ignition circuit 7 is kept closed, the high voltage 6 is applied to the ignition electrode and the spark is generated between the ignition electrode 6 and the burner body 5 to cause the burner to burn. Is ignited.

A first timer 9 provided to set an ignition time from when the first high voltage relay 8 is turned on to close the ignition circuit 7 to when the first high voltage relay 8 is turned off to open the ignition circuit 7.
Is connected to the low-voltage circuit 3 and the first high-voltage relay 8, and when the ignition contact 4 is turned on, the first timer 9 is turned on and the ignition time set by the first timer 9 (1.
For 5 seconds), the normally open contact of the first high-voltage relay is turned on, and when this ignition time has elapsed, the normally open contact of the first timer 9 becomes OF.
It becomes F, and the normally open contact 8a of the first high voltage relay 8 turns OFF,
At the same time that the ignition circuit 7 is opened, the normally closed contact 14 becomes OF.
It becomes F and the low voltage circuit 3 is opened.

The burner body 5, the ignition electrode 6, and the flame detector 10 whose output side is connected to the low-voltage circuit 3 for detecting the presence or absence of flame and transmitting a detection signal are connected to the detection circuit 11 in vacuum. A second high-voltage relay 12 having a normally-closed contact hermetically sealed and having the same rated working voltage as the first high-voltage relay 8 is incorporated. The normally-open contact of the second high-voltage relay 12 includes an ignition electrode 6 and a flame detector. Ten
And the second high voltage relay 12 is connected to the first high voltage relay 8.

After the ignition contact 4 is turned on and the ignition circuit 7 is closed, the normally open contact of the second high-voltage relay 12 is turned on and the detection circuit 11 is closed after a time longer than the ignition time set by the first timer 9. The second timer 13 provided for setting the delay time until the start of the detection circuit 11, that is, the time when the detection circuit 11 is closed after the ignition time has elapsed is connected to the low voltage circuit 3 in parallel with the first timer 9. Together with the second high voltage relay 12,
When the ignition contact 4 is turned ON, the second timer 13 is reached when the delay time (2.5 seconds in this example) set by the second timer 13 has elapsed, that is, one second after the ignition circuit 7 is opened.
The normally open contact of turns on and the detection circuit 11 is closed. When the post-ignition detection circuit 11 is closed, a rectified detection current flows between the burner body 5 and the ignition electrode 6 due to the conductive action of the burner flame, and an electric signal due to the burner flame is input to the flame detector 10. The flame detector 10 detects the presence or absence of a flame. When the burner is not ignited, or when the fire is extinguished after ignition, an alarm (not shown) connected to the output side of the flame detector 10, an alarm lamp, or the like notifies the flameless state.

Next, the operation and effect of the embodiment having the above configuration will be described.

In this example, the burner body 5, the ignition electrode 6, and the high-voltage side contact 2b of the transformer 2 are connected to the ignition circuit 7, which is provided with a first high-voltage relay 8 that opens and closes the ignition circuit 7. , Ignition electrode 6, and flame detector 10 for detecting the presence or absence of flame
A second high-voltage relay 12 that opens and closes the detection circuit 11 is provided in the detection circuit 11 connected to and the first high-voltage relay 8 is provided in the low-voltage circuit 3 connected to the low-voltage side contact 2a of the transformer 2. Is turned on to close the ignition circuit 7, and then the first high-voltage relay 8 is turned off to set the ignition time until the ignition circuit 7 is opened, and after closing the ignition circuit 7, After the ignition time has passed, the second high voltage relay 12
Second setting the delay time for closing the detection circuit 11 by turning it on
It is connected to the timer 13.

Then, the first and second high voltage relays 8 and 12 having high rated working voltage and having contacts capable of withstanding the high voltage are connected to the ignition circuit 7 and the detection circuit.
Since it is incorporated in the device 11, the problem that the contact on the high voltage side is damaged by the high voltage and malfunctions is solved, and switching between ignition and flame detection can be performed stably and accurately.

After the ignition of the burner, the ignition circuit 7 is opened and the low-voltage circuit 3 is opened after the ignition time set by the first timer 9 has elapsed.
The detection circuit 11 is opened after the delay time set by the timer 13 has elapsed, and a time lag (1 second in this example) is provided between the opening of the ignition circuit 7 and the opening of the detection circuit 11. Therefore, the adverse effect of the high voltage on the detection circuit 11 can be eliminated and the malfunction of the flame detector 10 caused by the high voltage can be prevented in advance.

Further, in this example, when the ignition circuit 7 is opened by the first timer 9, the low voltage circuit 3 is simultaneously opened by the normally closed contact 14, so that the adverse effect of the high voltage on the detection circuit 11 is surely eliminated. be able to.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is an electric circuit diagram of an ignition / combustion flame detection device, and FIG. 2 is a time chart. 2 ... Transformer 3 ... Low-voltage circuit 4 ... Ignition contact 5 ... Burner body 6 ... Ignition electrode 7 ... Ignition circuit 8 ... First high-voltage relay 9 ... First timer 10 ... Flame detector 11 …… Detection circuit 12 …… Second high voltage relay 13 …… Second timer

Front page continuation (72) Mitsuo Tomatsu Inventor Mitsuo Tomatsu 2720-1 Otoguchi, Nakashidanji, Moriyama-ku, Nagoya, Aichi Prefecture Yokoi Machine Works Co., Ltd. 2720 Address 1 Inside Yokoi Machine Works Co., Ltd. (56) References JP-A-49-94471 (JP, A) JP-B-62-50726 (JP, B2)

Claims (1)

[Scope of utility model registration request] 1. A burner body, an ignition electrode, and a high-voltage side contact of a transformer are connected to an ignition circuit, which is provided with a first high-voltage relay for opening and closing the ignition circuit.
A second high-voltage relay that opens and closes the detection circuit is provided in the detection circuit to which the ignition electrode and the flame detector that detects the presence or absence of flame are connected, and a low voltage connected to the low-voltage side contact of the transformer. In the voltage circuit, a first timer that sets an ignition time from when the first high voltage relay is turned on to close the ignition circuit to when the first high voltage relay is turned off to open the ignition circuit; An ignition / combustion flame detection device in a burner, characterized in that the ignition / combustion flame detection device is connected to a second timer for setting a time point at which the second high-voltage relay is turned on and the detection circuit is closed after the ignition time has elapsed.