JP3008536B2 - Fluid heating 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 fluid heating device for protecting functional components of a combustion device used for a water heater or a heating device using petroleum fuel from an unexpected rise in temperature.

[0002]

2. Description of the Related Art A conventional fluid heating apparatus of this type is described below.
A hot water boiler of a water heater will be described as an example with reference to FIG.

[0003] As shown in the figure, a burner 2 is provided in a frame-shaped case 1. A vaporizer 4 is connected to the burner 2 via a mixing chamber 3. The vaporizer 4 has a gas mixture inlet 5 at a lower portion thereof through which the gas mixture flows into the mixing chamber 3, a primary air supply port 6 disposed above the gas mixture inlet 5, and a vaporizer 4 from the primary air supply port 6. A fuel injection nozzle 7 facing the inside and a heater 8 embedded in the container wall are provided.

A first air passage 10 is formed on the side of the vaporizer 4 by a burner case 9 surrounding the side of the frame-shaped case 1 and the lower part of the mixing chamber 3. The second above the air passage 10
The primary air from the blower 12 is supplied to the carburetor 4 through the second air path 11, the first air path 10, and the primary air supply port 6. I have.

Reference numeral 13 denotes a pump for pumping fuel to the fuel injection nozzle 7, 14 a burner flame outlet, 15 an igniter, 1
6 is a heat exchanger, 17 is an exhaust port for discharging combustion gas.

In the above configuration, the heater 8 is energized,
When a temperature detector (not shown) detects that the vaporizer 4 has reached a predetermined temperature, the pump 13 is operated, and fuel is supplied from the fuel injection nozzle 7 into the vaporization chamber 4. At the same time, the blower 12 is also operated, and primary air for combustion is supplied into the vaporization chamber 4. The gas and the primary air which are vaporized in the vaporizer 4 become premixed gas and enter the mixing chamber 3 from the mixed gas inlet 5,
The gas is ejected from the burner port 14 and ignited by the igniter 15 to burn. After heating the water in the pipe with the heat exchanger 16, the combustion gas is discharged out of the machine through the exhaust port 17.

[0007]

In a conventional fluid heating apparatus using such a vaporizing burner, the function is achieved by warming cold water by fuel combustion and heat exchange.

By the way, between the blower 12 and the exhaust port 17, a flow path of a premixed gas or a combustion gas is formed. For this purpose, the carburetor 4 is controlled to a predetermined temperature after the combustion is stopped, during the period from the stop of the combustion to the start of the next combustion, or without switching to the combustion while energizing the heater 8,
When the heater 8 is ready to start combustion at any time, the so-called standby state is established.
The hot air generated by the heat capacity of the vaporizer 4 heated in the above becomes a rising airflow due to the convection of the natural draft, and the flow path has a small flow path resistance, that is, the temporary air supply port 6-the first air path 10-the second air path 11. -The air flows through the flow path of the air inlet 12a of the blower 12 and is discharged into the fluid heating device A.

As a result, the temperature inside the fluid heating device A rises, so that the temperature of the functional components disposed inside the fluid heating device A also rises, affecting its functions and characteristics. In particular, since the hot air directly heats the blower 12, the bearings of the motor and the fan made of synthetic resin are directly thermally affected, resulting in a problem that the durability is deteriorated and the function is impaired. Was.

[0010] This phenomenon is remarkable when a reverse wind of about a slight breeze flows from the exhaust port 17, and both of them cause an unexpected rise in the temperature of the functional parts and cause a failure.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem. It is an object of the present invention to suppress a rising airflow from a carburetor which occurs during a standby state, and to protect a functional component disposed therein from an unexpected rise in temperature. It is an object of the present invention to provide a fluid heating device which can be used.

[0012]

According to the present invention, in order to achieve the above object, a burner provided in a frame-like case is connected to the burner via a mixing chamber, and an air-fuel mixture flows into the mixing chamber. A mixture air inlet, a primary air supply port and a fuel injection nozzle disposed above the mixture air inlet,
A carburetor having a buried heater, and a blower passage provided on a side of the carburetor and for sending primary air from a blower to the primary air supply port, wherein the blower passage has at least an outlet of the blower. A second air path, which is an air path, has a first air path that is a folded air path, and the folded air path is disposed below the primary air supply port.

[0013]

According to the present invention, as described above, at least a part of the primary air blowing passage disposed on the side of the vaporizer is disposed below the primary air supply port, and the air passage at the outlet of the blower is provided. On the other hand, by being formed as a descending flow path that becomes a folded air path, an upstream side of the primary air supply port of the vaporizer has a descending flow path that is a flow path resistance disposed therebelow, When the vaporizer is heated and is in a standby state, the backflow of the hot airflow from the primary air supply port of the vaporizer to the air passage can be suppressed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.

The same components as those shown in the conventional example are denoted by the same reference numerals, and description thereof will be omitted. In the figure, a first air passage 10 is formed on the side of the vaporizer 4 by a burner case 9 surrounding the side of the frame-shaped case 1 and the lower part of the mixing chamber 3. A primary air inlet 18 through which the primary air from the blower 12 flows in through the second air passage 11 is provided below the air passage 10, that is, below the primary air supply port 6 of the vaporizer 4. ing. The second air passage 11 is arranged in a U-shape with the first air passage 10, and the blower 1
2 are provided.

The first air passage 10 and the second air passage 11
And the primary air inlet 18 form a U-shaped air passage,
A first air passage 10 which is a part of the first air passage 10 is formed in a descending flow path which goes downward from the primary air supply port 6 toward the primary air inlet 18, that is, a second air passage 11 which is an outlet air path of the blower 12. On the other hand, a folded air path is formed. In the above configuration, when in the standby state, hot air is generated in the carburetor 4 due to the heat capacity of the carburetor 4 heated by the heater 8, but the first blast passage 10 forming a part of the blast passage is formed.
Is a primary air supply port 6 upstream of the carburetor 4 on the low pressure loss side.
A downward flow path which is a folded air path from the air to the primary air inlet 18 is formed to have a flow path resistance against the convection of the natural draft of the hot air, thereby suppressing the back flow of the hot air to the air blowing path.

As described above, according to the fluid heating device of the embodiment of the present invention, the primary air from the blower 12 is formed at the outlet of the blower 12 in at least a part of the blower passage for sending the primary air to the primary air supply port 6. With respect to the second air passage 11, the first air passage 10 is formed so as to be a folded air passage,
Since the folded air path is disposed below the primary air supply port 6, the descending flow path serving as the folded air path acts as a flow path resistance against convection of natural draft of hot air,
As a result, the backflow of hot air into the air passage can be suppressed, so that the blower 12 arranged in the second air passage 11 and the functional components arranged in the fluid heating device A are protected from an unexpected rise in temperature. There is an effect that can be.

[0018]

As is apparent from the above description of the embodiment, according to the present invention, at least a part of the primary air blowing passage provided on the side of the carburetor is replaced with the primary carburetor. By forming it as a descending flow path that is a folded air path provided below the air supply port, the descending flow path becomes a flow path resistance against the convection of the natural draft of the hot air, and suppresses the backflow of the hot air to the air blowing path be able to.

Thus, it is possible to provide a fluid heating device capable of protecting the blower disposed in the ventilation passage and the functional components disposed in the fluid heating device from an unexpected rise in temperature.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a fluid heating device according to an embodiment of the present invention.

FIG. 2 is a side sectional view of a conventional fluid heating device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Frame-shaped case 2 Burner 3 Mixing chamber 4 Vaporizer 5 Mixed-air inlet 6 Primary air supply port 7 Fuel injection nozzle 8 Heater 10 1st ventilation path (downflow path) 11 2nd ventilation path (blowing path) 12 Blower 18 Primary air inlet

Continuation of the front page (72) Inventor Yuyuki Kubota 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-56-37406 (JP, A) JP-A-60-188717 (JP) , A) JP-A-4-327703 (JP, A) Jikken Sho 60-34892 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) F23L 1/00 F23D 11/10 F23D 11/44 F23L 5/00 F23K 5/20-5/22

Claims (1)

(57) [Claims] 1. A burner housed in a frame-shaped case, a mixture inlet connected to the burner via a mixing chamber, and a mixture mixture flowing into the mixture chamber, and disposed above the mixture mixture inlet. A carburetor having a primary air supply port and a fuel injection nozzle, and a buried heater, and an air passage disposed on the side of the carburetor and for sending primary air from a blower to the primary air supply port. The air path has a first air path that is a folded air path with respect to at least a second air path that is an outlet air path of the blower, and the folded air path is from the primary air supply port. A fluid heating device arranged to be located below.