JPS6396413A - Combustion apparatus - Google Patents

Abstract

PURPOSE:To prevent the abnormal deformation of a diaphragm by a method wherein one of open and closed valves for capacity control and open and closed valves at the upstream side are closed simultaneously by an extinction command, and one of the other open and closed valves already closed is opened temporar ily in a combustion apparatus such as for a water supplier, etc., equipped with a plurality of burners. CONSTITUTION:When the water quantity detected by a water quantity sensor 13 is under a set value in response to the closing of a faucet 14, the secondary solenoid valve 5B, a safety valve 7, and a proportional valve 6 are closed and a flame is extinguished, and a combustion LED 20 is turned off. At the same time of this action, a fan is operated at a rated revolution for a set time. At that time, the primary solenoid valve 5A already closed is opened for a fixed time and then closed. Thus, by the opening of one of open and closed valves for capacity control already closed at a point of time, gas pressure may be escaped and the abnormal deformation of a diaphragm may be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is typified by, for example, a water heater that is equipped with a plurality of burners and whose hot water supply capacity is adjusted by changing the number of burners used. Specifically, it is a combustion appliance that is equipped with a plurality of burners, and in the fuel gas supply path, a capacity adjustment on-off valve that operates separately is installed in each of the branch passages to each burner, and a valve is installed at the upstream side of the branch part. The present invention relates to a combustion appliance in which a diaphragm type flow rate regulating valve is interposed in the fuel cell, and an on-off valve is disposed upstream of the flow rate regulating valve.

[Conventional technology]

Taking a water heater as an example, conventional combustion appliances of this kind are configured to switch between open and downstream capacity adjustment valves based on a fire extinguishing command such as turning off a water flow sensor installed in the water supply channel. The fire was extinguished by automatically closing the side on-off valve at the same time.

[Problem that the invention seeks to solve]

However, when using the conventional water heater (combustion appliance),
When a fire is extinguished, the capacity adjustment on-off valve and the on-off valve are closed at the same time, so there is no escape for the gas pressure in the part of the fuel gas supply path between the flow rate adjustment valve and the downstream capacity adjustment on-off valve. , the gas pressure in the supply path is maintained at a high level. As a result, the high gas pressure continues to act on the diaphragm of the flow rate regulating valve throughout the combustion stop period, causing deformation of the diaphragm, and when the capacity regulating on-off valve and the on-off valve are opened for ignition, There is a problem that the diaphragm does not restore to its original regular shape, and the diaphragm is likely to malfunction at an early stage.

An object of the present invention is to prevent the above-mentioned abnormal deformation of the diaphragm.

[Means for solving problems]

The characteristic configuration of the combustion appliance according to the present invention is such that, based on a fire extinguishing command, a specific on-off valve among the on-off valves for capacity adjustment and an on-off valve on the upstream side are simultaneously closed, and then other capacity adjustment valves are closed. There is provided a controller that temporarily opens and closes one of the regulating on-off valves. The effects and effects thereof are as follows.

[For production]

Based on the fire extinguishing command, the open capacity adjustment on-off valve and the downstream on-off valve are simultaneously closed to extinguish the fire, and then one of the other closed capacity adjustment on-off valves is temporarily opened. In order to completely extinguish the fire by blocking the flow, the gas pressure in the downstream part of the flow TTM control valve in the fuel gas supply path is removed from the burner to the outside by temporarily opening the other capacity control on-off valve. You can miss it.

Moreover, focusing on the fact that multiple capacity adjustment on-off valves operate independently due to their functions, when releasing gas pressure, the capacity adjustment on-off valves are closed at the same time as the downstream on-off valve. Because other capacity adjustment on-off valves are used, for example, the on-off valve has a simpler configuration and control compared to the case where a capacity adjustment on-off valve is closed at the same time as the downstream on-off valve. In other words, when using a capacity adjustment on-off valve that is closed at the same time as the downstream on-off valve, it is necessary to operate the capacity adjustment on-off valve and the downstream on-off valve separately. As a result, a relay for controlling the opening/closing operation of the on-off valve is required for each on-off valve.However, when using another on-off valve for adjusting the capacity as in the present invention, the downstream side The operation of the on-off valve and the capacity adjustment on-off valve that is closed at the same time is the same,
Since the relays can be shared between them, the number of relays used can be reduced, and control can therefore be simplified.

〔Effect of the invention〕

As a result, according to the present invention, high gas pressure is not applied to the diaphragm of the flow N adjustment valve during combustion stoppage, making it possible to prevent abnormal deformation of the diaphragm and improve the durability of the diaphragm. .

〔Example〕

Next, examples of the present invention will be shown.

As shown in Figure 1, two adjacent burners (1A)
, (1B) and these burners (1A), (1B)
A heat exchanger (2) for heating the water supply and a fan (3) for supplying combustion air are provided, and the burner (1A)
.

Of the fuel supply path (4) to (1B), each burner (LA
).

A solenoid valve (5A) as a capacity adjustment opening/closing valve is attached to each of the branching path portions (4A) and (4B) to (1B),
(5B), a diaphragm type flow II regulating valve (6) is provided upstream of the branch, a solenoid valve (7) as an on-off valve is provided upstream of this, and a controller (8) is provided. We have developed an instantaneous water heater (an example of a combustion appliance) that can be switched between a large capacity heating water supply using two burners (1A) and (1B) and a small capacity heating water supply using one burner (1B). Configure.

The flow rate adjustment valve (6) includes a governor (6A) that maintains the flow rate at a set value regardless of gas pressure fluctuations based on the relationship between the gas pressure acting on the diaphragm (6a) and the force exerted by the spring (6b); This is a proportional valve consisting of a solenoid (6B) that changes the set value by changing the force of the spring (6b).

The water heater also includes a spark plug (9) for igniting one of the burners (LA) and (1B), and a flame for detecting the combustion flame of the other burner (1B). The water supply channel (12) to the heat exchanger (2) includes a water flow sensor (13) for detecting water flow. ) is interposed, and the heat exchanger (2)
A hot water supply path (15) from the water faucet (14) (hot water faucet) is provided with a water 1tii) one-section valve (16) and a temperature sensor (17) for detecting the hot water temperature. Note that the other burner (
1B) is ignited by the crowd from one burner (1^), and the burner that is extinguished to reduce the capacity is one burner (1A). 1^) and the corresponding capacity switching solenoid valve (5
A) will be referred to as a first burner and a first solenoid valve, respectively, and the other burner (1B) and the corresponding capacity switching solenoid valve (5B) will be referred to as a second burner and a second solenoid valve, respectively. Further, the downstream solenoid valve (7) is referred to as a safety valve.

The controller (8) includes the frame rod (10
), water amount sensor (13), temperature sensor (17), temperature setting device (18), power switch (SWI), and operation switch (SW2), the first and second solenoid valves (5A) , (5B) , safety valve (7), proportional valve (6)
, water flow control valve (16), igniter (11), operation LE
D (19) and combustion L E D (20), and the control will be explained below based on FIG. 2.

When the power switch (SWI) is ON and the operation switch (SW2) is turned on, the operation LED (1
9) is activated (lit), and hot water can be supplied.

In the above state, when the faucet (14) is opened, the water level sensor (1) is activated.
3) When the information from the fan (
3) starts the operation. In this way, pre-purge is performed.The fan (3) is first operated at the maximum rotation speed (N, ) for the first set time (t+) (about 0.3 seconds), and then the fan (3) is operated at the rated rotation speed (N*). Activate it with.

After the pre-purge is completed for the second set time (h) (about 1 second), the igniter (11) is activated and at the same time the first
The solenoid valve (5A) is opened, and then the third set time (t
. ).

As a result, when ignition occurs and the flame rod current (I) of the flame rod (10) is generated, the fourth set time (t4) starts from the start of generation of the flame rod current (1').
), the igniter (11) is stopped, and the combustion LED (20) is activated (lit).

The above is the ignition control for the first and second burners (1A).

The gas supply amount (Q) to (1B) is the maximum (
IIIax) but the setting style! (q), ignition is slow and ignition performance is improved.

Then, based on the temperature detected by the temperature sensor (17) and the set temperature of the temperature setting device (18), the proportional valve is adjusted so that the gas supply amount (Q) becomes the flow rate that makes the detected temperature equal to the set temperature. (6), and controls the rotation speed of the fan (3) according to the gas supply amount (Q), and when the difference between the detected temperature and the set temperature is less than the set temperature, and when the set temperature is below the set value, the first solenoid valve (
5A), and in addition, if the detected temperature does not rise to the set temperature even with the maximum heating capacity, the water fv
Throttle the M mode valve (16). This is combustion control for temperature adjustment accompanied by capacity switching.

In addition, at the initial stage of combustion control, the difference between the set temperature and the detected temperature is greater than the set temperature, so the gas supply amount (11) becomes the maximum (maχ), and the fan (3) also reaches the maximum rotation speed (N,
).

Then, when the faucet (14) is closed, the water flow sensor (13)
When the information from the 2nd solenoid valve (
5B), the safety valve (7), and the proportional valve (6) are closed, and the combustion LED (20) is turned off, and
From this point on, the fan (3) starts operating at the rated rotation speed (N,) for a fifth set time (ts) (about 7 minutes). On the other hand, at the above point, the first solenoid valve (5A)
is already blocked, its first solenoid valve (5^
) is closed after being opened for the sixth set time (t, ) (approximately 1 second), and the first solenoid valve (5A) is open, at the above point, that is, when the second solenoid valve (5A) is closed. Valve (5B)
(Safety valve (7)) is closed, and when the sixth set time (tb) has elapsed, the first solenoid valve (5A) is closed.
is occluded. This is normal fire extinguishing control.

Further, in the ignition control, the first solenoid valve (5A
) is released and the seventh set time (tF) has elapsed,
If the flame rod current (1) is not generated, it is determined that there is no ignition, and the second solenoid valve (5B), the safety valve (7), and the proportional valve (6) are immediately closed, and the combustion L E D (20) blinks, and the fan (
3) to the eighth set time (to) (i.

On the other hand, when the sixth set time (t6) has elapsed since the safety valve (7) was closed, the first solenoid valve (5A) is closed and the igniter (11) is stopped. let This is control in case of misfire.

Furthermore, when the flame load current (1) disappears during combustion, it is determined that there is a newcomer, and the first and second
Solenoid valve (58), (5B), safety valve (7), proportional valve (
6) is blocked, the combustion LED (20) is blinking, and the fan (3) is running at the maximum rotation speed (N, ).
It is operated for a set time (t5).

In the above embodiment, the second solenoid valve (5B) is the safety valve (
Although opened and closed at the same time as 7), the first solenoid valve (5A) opens before the safety valve (7) when igniting, and closes after the safety valve (7) when extinguishing the fire. As a result, when the safety valve (7) opens for ignition, the first solenoid valve (5A
) has already opened and the fuel gas is ready to be ejected from the first burner (1A), so when the safety valve (7) is opened, the fuel gas flows smoothly and the gas pressure is increased to the proportional valve (6).
It does not act as a shock on the diaphragm.

Moreover, even after the safety valve (7) was closed to extinguish the fire,
The first solenoid valve (5A) opens or remains open, and the proportional valve (6) of the fuel gas supply path (4)
) is opened to the outside in the first burner (1A), and the gas pressure escapes, so that no excessive gas pressure is applied to the diaphragm of the proportional valve (6).

Hereinafter, another practical side of the present invention will be shown.

[1] In the above embodiment, a proportional valve is provided as the flow rate adjustment valve (6), but the flow rate adjustment valve (6) may be a governor.

[2] In the above embodiment, two burners (1A) and (1B) were provided to adjust the capacity, but the burner (LA
), (1B) may be three or more.

Of course, there are two burners (1A) and (1B), and a combination where the flow IJI valve (6) is the governor.
), (1B) are three or more, and any combination in which the flow rate adjustment valve (6) is a proportional valve can be implemented.

[3] In the above embodiment, a water heater was shown, but the present invention
Needless to say, the present invention can be applied to other combustion appliances such as fan heaters.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the combustion appliance according to the present invention, and FIG. 1 is a schematic configuration diagram, and FIG. 2 is a time chart. (1A), (1B)...Burner, (4)・
...Fuel gas supply path, (4A), (4B)
... Branching road section, (5A), (5B). (7)...Opening/closing valve, (6)...Flow rate adjustment valve, (8)...Controller.

Claims (1)

[Claims] A plurality of burners (1A) and (1B) are provided, and the branch passage portions (4A) and (4B) to each burner (1A) and (1B) of the fuel gas supply passage (4) are operated separately. In addition to installing on-off valves (5A) and (5B) for capacity adjustment, a diaphragm-type flow rate adjustment valve (
6) and an on-off valve (7) installed at the upstream side of the flow rate regulating valve (6), the capacity regulating on-off valve (5A), (
5B) and the upstream on-off valve (7) are simultaneously closed, and then temporarily close one of the other closed capacity adjustment on-off valves (5A). A combustion device provided with a controller (8) for opening and closing.