JP3079673B2 - Combustor safety device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a safety device for a combustor used for a fan heater, an FF type hot air blower or the like.

[0002]

2. Description of the Related Art Generally, a combustor of this kind, for example, an oil combustor, supplies a fuel from a nozzle 22 and primary air from a primary air passage 23 to a vaporizing cylinder 21 to generate a mixed gas as shown in FIG. Then, the mixed gas is ejected from a flame hole 25 of a combustion section 24 mounted on the vaporizing cylinder 21 and burned. At this time, the flame formed in the flame hole 25 is supplied with the secondary air from the secondary air port 26 so as to be completely burned. The secondary air port 26 is provided via a secondary air passage 27 branched from the primary air passage 23, and is supplied with air from a blower 28. On the other hand, a flame rod 29 is provided outside the flame hole 25 of the combustion part 24, and the state of the flame is monitored by the flame rod 29. If an abnormal state is reached, an output is sent to the control part 30 to stop the combustion. It has become.

[0003]

However, in the above-described conventional combustor, even if the connection portion 27a of the secondary air passage 27 is disconnected and the secondary air is not supplied, the flame current detected by the frame rod 29 is detected. The combustion does not change much, and the combustion is continued as it is, and a large amount of CO is generated. Alternatively, the exhaust gas containing a large amount of CO in the combustion chamber 31 flows backward from the detached secondary air passage 27, and from the opening thereof. There was a problem of leaking indoors. That is, although the flame current is mainly taken from the primary flame in the flame, the combustion state of the primary flame does not change so much even when the secondary air is exhausted, so that the flame rod cannot be detected by the flame rod 29,
The combustion continued as it was.

[0004] The present invention has been made to solve the above-mentioned problem, and is intended to improve the safety by reliably detecting even when the secondary air is no longer supplied.

[0005]

SUMMARY OF THE INVENTION The present invention achieves the above object by providing primary air for mixing with fuel.
Via a primary air passage and a connection branching off from the primary air passage
Secondary air passage to supply secondary air to the flame side of the combustion section
When a blower for supplying air to the primary air passage, and a temperature sensor for detecting the temperature change of the secondary air, the temperature
The degree sensor is located in the middle of the secondary air passage downstream of the connection
And a control unit for stopping combustion of a combustion unit based on an output from the temperature sensor when the secondary air passage is disconnected from the connection unit and secondary air cannot be supplied.
The configuration is provided .

[0006]

According to the present invention, with the above structure, the primary air passage
Supply secondary air through a branched secondary air passage
In the combustor, the secondary air passage is connected
If off from Part secondary air is not supplied, connected
Temperature sensor located downstream of the section
The temperature rise due to the temperature sensor can be quickly detected, and the control unit can stop the combustion in the combustion unit based on the output from the temperature sensor.
An abnormal state in which exhaust gas containing a large amount of CO is released into the room can be prevented.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS.

In FIG. 1, reference numeral 1 denotes a bottomed cylindrical vaporizing cylinder.
A nozzle 3 for supplying fuel from the pump 2 and a primary air supply port 6 for supplying primary air for combustion from a blower 4 through a primary air passage 5 face a part of the eccentric position of the peripheral wall. Reference numeral 7 denotes a heater buried in the vaporizing cylinder 1, and reference numeral 8 denotes a combustion section covered by an upper opening of the vaporizing cylinder 1, and a large number of flame holes 9 are provided on a peripheral wall thereof. Reference numeral 10 denotes a burner cap that covers the upper opening of the combustion section 8, and 11 denotes a burner ring that is disposed concentrically outside the combustion section 8.
Is provided with a secondary air port 13 for supplying secondary air through a secondary air passage 12 branched from the primary air passage 5.
Reference numeral 14 denotes a frame rod disposed so as to face the flame hole 9 of the combustion section 8, and reference numeral 15 denotes a temperature sensor provided on the downstream side of the connection section 12a in the middle of the secondary air passage 12.

In the above configuration, at the start of combustion, the fuel injected into the vaporizing cylinder 1 via the pump 2 and the nozzle 3 is vaporized in the vaporizing cylinder 1 which is heated to a high temperature by the heater 7.
The air is premixed with the primary air for combustion supplied into the vaporization cylinder 1 through the blower 4, the primary air passage 5, and the primary air supply port 6.
This premixed gas flows into the combustion section 8 while swirling in the vaporization cylinder 1, and is ejected from the flame holes 9 in the side wall of the combustion section 8. Then, when the fuel is ignited by an appropriate ignition means, combustion starts, and the flame hole 9
Form a flame that is almost in close contact with The flame is supplied with secondary air through a secondary air passage 12 branched from the primary air passage 5 and a secondary air port 13 provided in the burner ring 11, so that the flame is completely burned.

On the other hand, a frame rod 14 provided to face the flame hole 9 of the combustion part 8 monitors the state of the flame formed in the flame hole 9, and outputs an output to the control part 16 when an abnormal state occurs. It is designed to stop out-combustion.

Here, as shown in FIG. 2, when the connecting portion 12a in the middle of the secondary air passage 12 is disengaged for some reason and the secondary air is not supplied, the secondary air from which the secondary air is normally ejected is normally supplied. The secondary air is no longer supplied from the port 13 and cannot be completely burned, so that a large amount of CO starts to be generated. At the same time, the high-temperature exhaust gas containing this CO flows backward and jets into the room from the connection portion 12a. And at this time the primary air
Although it is slightly reduced, it can be detected with the frame rod 14.
The combustion cannot be stopped because it does not lead to abnormal combustion.
Therefore, abnormal combustion will be continued. However, at this time, the temperature of the temperature sensor 15 provided on the downstream side of the connecting portion 12a rises, and the control unit 16 stops the combustion of the combustion unit 8 based on the output from the temperature sensor 15, so that abnormal combustion occurs.
Burning can be avoided. That is, the primary air passage 5
Supply secondary air through the secondary air passage 12 branched from
In the air supply configuration, the secondary air passage 1
2 is disengaged secondary air is not supplied from the connecting portion, frame
Abnormal state of said not be detected by Muroddo 14 can be reliably detected, thereby improving the safety.

[0012] Figure 3 shows a reference example, a blower for supplying primary air for combustion is 4, 17 is a blower for supplying secondary air, the secondary air passage 1 as in the configuration of Example
2 does not branch off from the primary air passage 5, and the primary air passage 5 and the secondary air passage 12 have independent configurations. Also in this case, similarly to the above-described embodiment, the connection portion 12a in the middle of the secondary air passage 12 is disconnected for some reason, or the blower 4 for supplying the secondary air stops for some reason, and the secondary air Is no longer supplied, the high-temperature exhaust gas flows back through the secondary air passage 12 and the temperature of a temperature sensor 15 provided near the connecting portion 12a rises. Based on the output from the temperature sensor 15, the control unit 16 controls the combustion unit. 8
Stops burning.

According to the configuration of the above embodiment, the primary air passage
The secondary air is supplied through a secondary air passage 12 branched from
In the air supply configuration adapted to supply air, the secondary air passage
12 comes off and the secondary air is no longer supplied,
In an abnormal state such that the temperature cannot be detected by the secondary air passage 14, the temperature sensor 15 provided on the downstream side of the connection portion 12a in the middle of the secondary air passage 12 detects a temperature rise due to the backflow of the high-temperature exhaust gas without the supply of the secondary air. When the control unit 16 stops the combustion of the combustion unit 8 based on the output from the temperature sensor 15, an abnormal state such as generation of a large amount of CO due to incomplete combustion and outflow of exhaust gas into the room is achieved. Can be prevented.

[0014]

As described above, the safety device for a combustor according to the present invention comprises a secondary air passage branched from the primary air passage.
A temperature sensor is provided on the downstream side of the connection part in the middle of the secondary air passage to detect a temperature change of the secondary air, and based on an output from the temperature sensor, the control unit stops the combustion of the combustion unit. The secondary air passage is connected to
The secondary air is no longer supplied and the frame
Even in an abnormal state that cannot be detected by the rod, it is possible to prevent an abnormal state in which a large amount of CO is generated due to incomplete combustion and an exhaust gas flows out into the room, and the safety of the combustor can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a combustor according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the combustor when the secondary air is no longer supplied.

FIG. 3 is a sectional view of a combustor according to a reference example of the present invention.

FIG. 4 is a sectional view of a conventional combustor.

[Explanation of symbols]

 4 Blower 8 Combustion unit 12 Secondary air passage 12a Connection unit 15 Temperature sensor 16 Control unit

(56) References JP-A-62-223525 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23N 5/24 104 F23N 5/14

Claims (1)

(57) [Claims] 1. Supplying primary air for mixing with fuel
A primary air passage and a connection branching off from the primary air passage
A secondary air passage for supplying secondary air to the flame side of the burner section through a blower for supplying air to the primary air passage, the secondary
A temperature sensor for detecting a change in temperature of the secondary air,
The temperature sensor is in the middle of the secondary air passage downstream of the connection
And the secondary air passage is separated from the connection part.
When secondary air is no longer supplied Te, safety device combustor is provided with a control unit for stopping the combustion in the combustion section based on the output from the temperature sensor.