JPH0241472Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention is a combustion device used for example in an instantaneous water heater. burners are housed horizontally in multiple stages above and below, these burners are provided with capacity switching valves, and a sensor is provided in the combustion gas flow path to detect the presence or absence of combustion flame from the burners. Regarding type combustion devices.

[Prior Art] Conventionally, in this type of combustion apparatus, a throttle valve is generally used as a valve for switching burner capacity, and when switching to a low capacity, the flow of fuel gas to each burner is The structure was such that supply was reduced. Furthermore, for this reason, there are no particular restrictions on the location of the sensor that detects the presence or absence of combustion flames, and it has usually been placed near the vertical center of the combustion gas flow path (see the literature). cannot be shown).

[Problems to be solved by the invention] However, when switching the burner capacity, it is difficult to supply fuel gas only to the upper burner among burners stored in multiple upper and lower stages, or to supply fuel gas to the lower burner. It is also possible to switch the capacity by supplying only fuel gas.In this case, if the sensor was placed near the vertical center of the combustion gas flow path as in the past, when switching to a low capacity, the It is conceivable that a situation may occur in which the sensor cannot reliably detect the presence or absence of combustion flame.

In other words, if the configuration is such that fuel gas is supplied only to the lower burner when switching to low capacity, the combustion flame will move away from the sensor, making reliable detection impossible. On the other hand, if the fuel is supplied only to the upper burners, the combustion flame will move away from the sensor, and in addition, the combustion flame will rise upwards, making reliable detection even more difficult.

An object of the present invention is to provide a combustion device that can always and reliably detect the presence or absence of a combustion flame in a type that switches the capacity without using a throttle valve.

[Means for Solving the Problems] In order to achieve this objective, the horizontally installed type combustion apparatus according to the present invention is configured such that at least the burner in the top stage is configured to supply fuel gas to the
The present invention is characterized in that a sensor for detecting the presence or absence of combustion flame is arranged above the combustion gas flow path in correspondence with the uppermost burner.

[Function] In this way, the sensor is disposed at a position corresponding to the burner on the uppermost stage, and the structure is such that fuel gas is supplied to the burner on the uppermost stage at a minimum even when switching to low capacity. Therefore, the presence or absence of combustion flame can be reliably detected by the sensor not only when the capacity is high but also when the capacity is low.

[Effect of the invention] Therefore, even in a type of combustion equipment in which the capacity is switched by switching the supply of fuel gas to burners arranged in multiple stages above and below, it is possible to always ensure reliable operation regardless of the state of capacity switching. It is now possible to detect the presence or absence of a combustion flame, and to detect unexpected situations such as incomplete combustion, ignition errors, or extinction.

[Example] Next, embodiments of the present invention will be described.

FIG. 6 is a plan view showing the schematic structure of a horizontally installed instantaneous water heater using the combustion device of the present invention with respect to the main body of the water heater. A burner 2 for heating the burner 2 and a fan 3 for forcing combustion air are equipped, and a fuel gas supply line 4 for the burner 2 includes a safety solenoid valve 5, a gas governor 6, and a capacity switching solenoid valve 7. However, the water supply pipe 8 for the water heating heat exchanger 1 is also equipped with a water governor 9 and a water flow switch 1.
0 is inserted respectively.

A hot water supply pipe 11 from the water heating heat exchanger 1 is connected to a hot water tap 13 via an extension pipe 12.

To explain the operation of this horizontally installed instant water heater, based on the ON operation of the water flow switch 10 accompanying the opening operation of the hot water tap 13, the fan 3 is started by the controller 14, and the safety solenoid valve 5 is activated. The spark plug is opened and the spark plug is 15A.
is activated and burner 2 ignites.

Also, based on the OFF operation of the water flow switch 10 accompanying the closing operation of the tap 13, the controller 14
As a result, the safety solenoid valve 5 is operated to close, the burner 2 is extinguished, and the fan 3 is stopped.

In the figure, 15B is a flame rod which is an example of a sensor that detects the presence or absence of a burner combustion flame.Based on the detection result of the flame rod 15B, if the burner ignites incorrectly, goes out, or incomplete combustion occurs, the safety solenoid valve 5 will be automatically blocked.

Regarding the specific assembly structure of the water heating heat exchanger 1, the burner 2, and the fan 3, as shown in Figs. A horizontally oriented cylindrical body 16 is provided, and the burner 2 is housed at one end of the cylindrical body 16 in a horizontal position over almost the entire cross section of the cylindrical body 16. A water tube type water heating heat exchanger 1 is installed at the opening on the other end side, and a burner 2 is installed inside the horizontal cylindrical body 16.
This is a horizontal combustion gas flow path F from the water heating heat exchanger 1 to the water heating heat exchanger 1.

The burner 2 consists of two burners 2A and 2B arranged in upper and lower stages.
Fuel gas is supplied to B from the fuel gas supply pipe 4, respectively. At this time, when the capacity is switched to the high capacity side by operating the capacity switching solenoid valve 7, fuel gas is supplied to both burners 2A and 2B, and when the capacity is switched to the low capacity side, fuel gas is supplied only to the upper burner 2A. is configured to be supplied.

The cylindrical body 16 is divided into a burner storage portion 16A and a combustion gas flow path forming portion 16B, and both 16A and 16B are integrated by flange connection, and the flame rod 15B is installed in the burner storage portion 16A. This flame rod 15B is disposed in front of the upper stage burner 2A, that is, above the combustion gas flow path F.

Therefore, of course, when the capacity is switched to the high capacity side by operating the capacity switching solenoid valve 7,
Even when switched to the low capacity side, the flame rod 1B located in front of the upper burner 2A
, the presence or absence of combustion flame can be reliably detected, and if the flame rod 15B cannot detect the presence of combustion flame regardless of whether the water flow switch 10 is turned on, the safety solenoid valve 5 is automatically closed. Prevents unexpected situations due to incomplete combustion or ignition errors.

On the other hand, a cross-flow fan is used as the fan 3, and the cross-flow fan 3 is
is arranged so that almost the entire fan 3 (including the fan case 3A) is accommodated in the virtual extended cylinder portion 16' at one end of the cylindrical body 16, and the fan rotation axis P has a rectangular cross-sectional shape of the cylindrical body 16. They are arranged along the long sides.

That is, by setting the shape of the burner 2 and the water heating heat exchanger 1, the cross-sectional shape of the cylindrical body 16 is made into a rectangular shape with as large an aspect ratio as possible with the long side direction being almost horizontal. The cylindrical body 16 and the cross-flow fan 3 are arranged relative to each other so that the cross-sectional shape of the cross-flow fan 3 and the projected shape of the cross-flow fan 3 when viewed in the direction of the rotation radius overlap almost exactly in the direction of the cylinder axis of the cylindrical body 16. As a result, the overall configuration of the main part of the water heater consisting of the water heating heat exchanger 1, burner 2, and fan 3 can be made compact.
And, it is made into a small rectangular parallelepiped shape with a top and bottom thickness dimension d,
The overall structure of the horizontally installed instantaneous water heater has been made compact and thin.

In the figure, 17 is a motor for driving a cross-flow fan.

Burner storage portion 16 in horizontal cylindrical body 16
A hopper type wind guide 18 is integrally connected to the fan side opening of A, and the width of the hopper type wind guide 18 is formed to be narrower toward the fan side in terms of the dimension in the short side direction of the cross-sectional shape of the cylindrical body 16. The slit-shaped discharge port of the cross-flow fan 3 is connected to the fan-side slit-shaped opening of 18.

In addition, punching plates 19 and 20 for regulating the air are stretched over the entire surface of each opening at the cylindrical body connection side opening and the fan side opening of the hopper type wind guide 18, and further, From the tongue part 3a of the fan casing 3A, there is a guide tongue piece with an inclined posture that guides and promotes dispersion of the discharged air from the fan 3 in the vertical thickness direction of the water heater (the short side direction of the cross-sectional shape of the cylindrical body). 21 are arranged continuously over almost the entire length of the fan casing 3A in the longitudinal direction.

In other words, the two-stage punching plates 19 and 20 sufficiently convert the dynamic pressure of the fan discharge air into static pressure to equalize the velocity distribution of the combustion air, and the guide tongues 21 disperse the fan discharge air. By promoting these, as a cooperative effect, the combustion air supply state to the entire burner 2 is made uniform, and
Accordingly, the ventilation condition in the combustion gas flow path F in the cylindrical body 16 is made uniform, thereby maintaining a good combustion condition of the burner 2 and maintaining high heating efficiency in the water heating heat exchanger 1. It's like this.

Further, by applying the cross-flow fan 3, the distribution width of the fan discharged air is only the width of the short side of the rectangular cross-sectional shape of the cylindrical body 16, and the above-mentioned two-stage punching plates 19, 20 and Since a high air regulating effect is obtained by the guide tongue piece 21, the length of the hopper type wind guide 18 is considerably shortened, which also allows the main part of the water heater to be considerably miniaturized.

To explain the specific structure of the horizontal burner 2 disposed in the burner storage portion 16A of the cylindrical body 16, as shown in FIGS. are arranged in two rows, upper and lower, over almost the entire cross section of the cylindrical burner storage portion 16A, and are connected to the fuel gas supply pipe 4 in the recesses of the bending plate members 19A. Two burners 2A and 2B are arranged along the longitudinal direction of the bending plate member 19A.

The refracting plate member 19A has an air jet port a for ejecting combustion air toward the burners 2A and 2B, and the burners 2A and 2B have an air jet port a directed toward the inclined inner surface of the recess in the refractive plate member 19A. The gas ejection port g that ejects fuel gas is connected to the bending plate-like member 19A.
The air outlet a and the gas outlet g are arranged alternately in the longitudinal direction.

In other words, due to the above-mentioned alternating arrangement, a swirling flow is generated in the space located between the air outlet a and the gas outlet g which are adjacent to each other as the combustion air and fuel gas are ejected. Therefore, the mixing effect of the jetted combustion air and the jetted fuel gas is enhanced to improve combustion performance.

In FIGS. 1 and 3, 22 is a water heater exterior casing, and the exterior casing 22
It also has a rectangular parallelepiped shape with a thin top and bottom.

In the figure, 23 is a water supply joint, 24 is a hot water supply joint, 2
Reference numeral 5 denotes gas joints, which are respectively protruded from the upper surface of the water heater. Further, on one of the surfaces of the exterior casing 22 corresponding to the left and right side surfaces of the water heater, there is an exhaust port 26 connected to the exhaust side opening of the cylindrical body 16, and on the lower surface of the exterior casing 22, a cross-flow Inlet ports 27 communicating with the inlet ports of the fans 3 are respectively formed.

Further, 28 in the figure is a metal fitting for connecting and supporting a horizontally installed water heater to the lower surface of a wall cabinet or the like.

In addition, FIG. 7 shows another embodiment, in which a plate is provided swingably around an axis Q parallel to the rotation axis P of the fan 3 near the joint between the hopper type wind guide 18 and the punching plate 19. A body 29 is provided, and when the capacity is switched to the low capacity side by operating the capacity switching solenoid valve 7, this plate body 29 swings toward the punching plate 19 side, and the part of the punching plate 19 corresponding to the lower burner 2B is moved. It is configured to cover. Such a plate 2
By providing 9, the entire amount of combustion air can be forcedly ventilated to the upper stage burner 2A side which is burning at low capacity.

The above explanation has been given using an example in which a combustion device consisting of a burner 2, a cylindrical body 16, etc. is applied to an instantaneous water heater. Needless to say, it can be applied to In addition, the explanation was given using an example in which the burners 2 are arranged in two upper and lower stages 2A and 2B, but the burners are arranged in three upper and lower stages.
Of course, it is also possible to implement the method in a case where the structure is arranged in more than one stage.

[Brief explanation of drawings]

1 to 6 show an embodiment in which the combustion device of the present invention is applied to a water heater, in which FIG. 1 is a sectional view from the front, FIG. 2 is a sectional view from below, and FIG. 3 is a sectional view from the bottom. FIG. 4 is a sectional view taken along the - line in FIG. 1, FIG. 5 is an enlarged sectional view showing the burner configuration, and FIG. 6 is a schematic configuration diagram of the water heater. or,
FIG. 7 is a sectional view of a main part showing another embodiment. 2A, 2B... Burner, 7... Capacity switching valve, 1
5B...Sensor, 16...Cylindrical body, F...Combustion gas flow path.

Claims (1)

[Scope of utility model registration request] A plurality of burners 2A and 2B are housed horizontally in a horizontal cylindrical body 16 forming a horizontal combustion gas flow path F, and in multiple upper and lower stages, and a capacity switching valve 7 is provided for these burners 2A and 2B. In addition to providing
Burners 2A and 2B are provided in the combustion gas flow path F.
This is a horizontally installed type combustion apparatus equipped with a sensor 15B for detecting the presence or absence of combustion flame from the combustion apparatus, and when the capacity is switched to low capacity by operating the capacity switching valve 7,
The horizontally installed type is configured to supply fuel gas to at least the uppermost burner 2A, and the sensor 15B is arranged above the combustion gas flow path F in correspondence with the uppermost burner 2A. Combustion device.