JPH04251111A - Gas burner - Google Patents

Abstract

PURPOSE:To eliminate a special conversion work at the time of converting the kind of gas fuel by making it possible to carry out automatically in a gas equipment the setting of fuel specification that fits the kind of gas fuel. CONSTITUTION:A test combustion is made by a test burner 2 that is provided separately from a main combustion device B, and the air excess rate at this time is changed gradually by an air excess rate adjusting means 3, and based on the air excess rate when an excellent state of combustion is given a combustion specification setting device 6 that makes the air excess rate in the combustion specification of a main burner B fit for the above mentioned air excess rate is provided, and by the test combustion signal preceding the continuous operation of the main burner B the above mentioned test combustion device C is operated.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application and Summary of the Invention] The present invention relates to a gas combustion device, and the present invention allows combustion specifications corresponding to the gas type to be automatically set in the gas appliance, thereby making it possible to change the combustion specifications when changing the gas type. This eliminates the need for parts replacement, etc.

0002

[Prior Art and Problems] In gas appliances, the maximum calorific value of the combustion device is set to a fixed value, but since the calorific value per unit volume and the required amount of air differ depending on the type of gas, common gas burners are In order to keep the maximum calorific value constant by burning different types of gases, it is necessary to determine combustion specifications suitable for each type of gas. In other words, it is necessary to determine the gas supply amount and air supply amount (combustion specifications) to the burner according to the compatible gas type. Conventionally, a combustion device section is configured to match the combustion specifications of a specific gas type at the production stage, and this is assembled into a gas appliance and shipped. Therefore, if a gas type different from the specific gas type is combusted, poor combustion or excess or deficiency of calorific value will occur in the combustion device. Additionally, if the type of gas supplied is changed after the installation of gas appliances, it is necessary to change the combustion specifications to match the newly supplied gas type. This combustion specification was changed.

[0003] As described above, determining the combustion specifications of a combustion device in advance in accordance with a specific type of gas is very inconvenient in the production process of appliances. Further, the adjustment work of the equipment when changing the type of gas to be supplied is also troublesome. Therefore, there is a desire for a combustion device that can adapt to a plurality of gas supply types, but the reality is that this has not been realized to date. The present invention has been made in view of the above, and an object of the present invention is to automatically set combustion specifications that match the supplied gas in order to eliminate the need for gas type conversion work. do.

0004

[Technical Means] The technical means of the present invention for solving the above problems is as follows:
an auxiliary gas circuit (22) branched from the main gas circuit (10) and connected to the test burner (2); and a gas from the auxiliary gas circuit (22) to the test burner (2).
Excess air ratio adjusting means (3) for adjusting the excess air ratio when combustion is performed in the combustion process, and the excess air ratio adjusting means (3)
The test burner (2
) is combusted and a good combustion state is obtained, the determination means (4) enters the output state, and the excess air ratio adjustment means (3) when the output from the determination means (4) is generated. A test combustion device (C) consisting of a storage means (5) for storing set values is provided separately from the main combustion device (B), and the excess air ratio of the combustion specifications of the main combustion device (B) is stored. A combustion specification setter (6) adapted to the value stored in the means (5) is provided, and the test combustion device (C) is operated by a test combustion signal prior to the operation of the main combustion device (B). That's true. (See Figure 1)

[0005]

[Operation] The above technical means operates as follows. Prior to burning the main combustion device (B), the test combustion device (
C) is activated. Thereby, the actual gas supplied to the main gas circuit (10) passes through the auxiliary gas circuit (22) branched from the main gas circuit (10) to the test burner (
2), and at the same time, the excess air ratio adjusting means (3) operates. As a result, the test burner (2) burns in a manner in which the excess air ratio changes gradually or in stages. At the same time, the determining means (4) becomes operational. During this period, when the excess air ratio reaches the optimum value, the test burner (2)
The combustion state is the best, but at this time, the determination means (
4) becomes an output state, and the storage means (5) stores the value set by the excess air ratio adjusting means (3) based on the output of the determination means (4). Next, the combustion specification setter (6) sets the combustion specification based on the stored value in the storage means (5), and from then on, the main combustion device (B) will be combusted according to the combustion specification. . This combustion specification is compatible with the gas actually supplied to the main gas circuit (10). Therefore, during combustion in the main combustion device (B), combustion specifications that match the gas actually supplied are automatically set.

[0006]

[Effect] Since the main combustion device (B) burns with the combustion specifications that match the gas actually supplied, there is no need to change the gas type.

[0007]

Embodiments Next, embodiments of the present invention described above will be described in detail with reference to the drawings. The embodiment shown in Fig. 2 and below is implemented in a water heater equipped with a forced combustion type combustion device. A main combustion device (B) is configured inside. In this main combustion device (B), air and gas are supplied to a mixing chamber (M) below a combustion surface (P) having a large number of flame holes, and this air-gas mixture is heated to the combustion surface (P). It burns on the top surface. A discharge port of an air supply fan (F) for supplying combustion air is opened at the bottom of the burner box, and air is supplied from this air supply fan (F) to the mixing chamber (M). still,
The rotation speed of this air supply fan (F) is variable, and by adjusting the rotation speed, the amount of air supplied can be adjusted. The mixing chamber (M
) is introduced into the main gas circuit (10), and this main gas circuit (10) is provided with a gas proportional valve (11), and the amount of gas supplied is adjusted by adjusting the valve opening. The valve opening degree is adjusted by changing the electrical input signal level applied to the gas proportional valve (11).

In the main combustion device (B) configured as described above, the input signal level is adjusted in accordance with the opening degree of the gas proportional valve (11) of the main gas circuit (10), and the rotational speed of the intake fan (F) is adjusted. Although the excess air ratio can be adjusted by adjustment, a combination of the input signal level of the gas proportional valve (11) and the rotation speed of the air supply fan (F) that is suitable for each excess air ratio is specified in advance. For this reason, a gas amount setting circuit (61) is provided that outputs a signal at a level that matches the input of a signal corresponding to a specific excess air ratio (excess air ratio signal) to the gas proportional valve (11). At the same time, the air amount setting circuit (6
2) is provided, and the combination of these two circuits becomes the combustion specification setting device (6) described above. The excess air ratio signal is inputted from a storage means (5) which will be described later.

[0009] There are test burners (2
), and this test burner (2) has a nozzle (23) protruding from the center of the bottom of a bottomed cylindrical body (21) that is open at the top, and a small fan (31) with a variable rotation speed.
) is open and faces the upper combustion plate (24). The amount of gas supplied to the test burner (2) is set by the diameter of the nozzle (23), and the amount of combustion air is controlled by adjusting the rotation speed of the small fan (31). Therefore, this small fan (31)
The rotation speed adjusting means of this small fan (31) becomes the above-mentioned excess air ratio adjusting means (3). The small fan (31) has a configuration in which the rotation speed changes by adjusting the voltage applied to it, and the voltage regulator (32)
serves as the rotation speed adjusting means. When the test combustion apparatus (C) equipped with these is operated, the voltage set by the voltage regulator (32) is adjusted so as to gradually increase over time within a certain range.
) is constantly input into the storage means (5). A thermocouple (41) is provided on the side wall of the bottomed cylindrical body (21) and is located near the combustion plate (24). This thermocouple (41) is arranged at a position where the output voltage is highest when the combustion state in the combustion plate (24) is most stable, and its output is detected by the peak value detection circuit (42).
) is entered. This peak value detection circuit (42) is designed to compare the output from the thermocouple (41) with the previous output value every unit time, and when the subsequent output value is lower than the previous output value. It becomes the output state (H) at the moment when the output state is reached. When the peak value detection circuit (42) is in the output state (H), the storage means (5) is activated as described above.
The set voltage of the voltage regulator (32) input to is stored.

In the gas combustion apparatus constructed as described above, each part is controlled by a microcomputer, and this control program is based on the flow chart shown in FIG. The operation of each part will be explained below based on this flowchart. Once gas appliances are installed,
First, a test combustion operation is performed using the test combustion device (C). When the test combustion signal is input, the on-off valve (25) inserted into the auxiliary gas circuit (22) opens and a certain amount of gas is supplied to the test burner (2), and at the same time the small fan (31) starts operating. condition, and the ignition device (not shown)
The test burner (2) enters the combustion state. When the test burner (2) continues to burn, the voltage applied to the small fan (31) is gradually increased by the voltage regulator (32). As a result, the excess air ratio in the test burner (2) gradually increases, and the combustion state under this condition is constantly monitored by the thermocouple (41). When the combustion condition is most stable, the thermocouple (41)
The peak value detection circuit (42) captures this point in time because the output from the peak value reaches a peak. At this time, the peak value detection circuit (
42) becomes the output state (H), and the output value of the voltage regulator (32), which is constantly input to the storage means (5), is stored at the time when the output from the peak value detection circuit (42) occurs. . Thereafter, the on-off valve (25) is closed, and after that, the small fan (31) is continuously operated for a certain period of time, and then the operation of the small fan (31) is stopped.

[0011] As a result, the test combustion operation is stopped, and then the main combustion device (B) enters the combustion state. However, since the appliance in this example is a water heater, the water circuit (E) of the heat exchanger (E) W) is opened, the water pressure-responsive gas valve (12) interposed between this water circuit (W) and the main gas circuit (10) opens.
) opens the main gas circuit (10) to the main combustion device (B).
will be released. At this time, the gas proportional valve (
11) is set to a predetermined opening degree, and the rotation speed of the air supply fan (F) is set to a predetermined value by the output from the air amount setting circuit (62). The excess air ratio determined will correspond to that determined by test combustion runs. Therefore, the main combustion device (B
) combustion specifications are adapted to the gas actually supplied to the main gas circuit (10), and the combustion flame formed on the combustion surface (P) is stable.

In the above embodiment, the main combustion device (B)
Both the gas amount in the main gas circuit (10) and the rotational speed of the air supply fan (F) are adjusted to set combustion specifications that match the excess air ratio stored in the storage means (5). It is also possible to set the combustion specifications by changing only the other value without changing one value. In addition, regarding the test combustion device (C), we have changed to a method that adjusts the excess air ratio by changing both the air amount and gas amount, or a method that changes the excess air ratio by changing only the gas amount. It is also possible to do so. In this embodiment, the voltage regulator (32) of the test combustion device (C) has a configuration in which the voltage regulator (32) itself gradually changes its output level from a low level range to a high level range. For example, it is also possible to use a combination of a variable resistor and its driving means. Note that the determining means (4) is a thermocouple (41
), but may also use optical fibers, CO sensors, etc. Further, the test combustion operation may be performed only once after the appliance is installed, or may be performed every time the appliance is used. It goes without saying that the combustion device can also be of the type described above, and that it can be implemented in appliances other than the water heater described above.

[Brief explanation of the drawing]

[Fig. 1] Diagram explaining the principle of the present invention

FIG. 2: Schematic diagram of an embodiment of the present invention

[Figure 3] Flowchart diagram of control program

[Explanation of sign]

(B): Main combustion device (2): Test burner (3
): Excess air ratio adjustment means (4): Judgment means (5): Storage means
(6): Combustion specification setter (C): Test combustion device

Claims (1)

[Claims] [Claim 1] Test burner (2) and main combustion device (B)
an auxiliary gas circuit (22) branched from the main gas circuit (10) and connected to the test burner (2); and a gas from the auxiliary gas circuit (22) to the test burner (2).
Excess air ratio adjusting means (3) for adjusting the excess air ratio when combustion is performed in the combustion process, and the excess air ratio adjusting means (3)
The test burner (2
) is combusted and a good combustion state is obtained, the determination means (4) enters the output state, and the excess air ratio adjustment means (3) when the output from the determination means (4) is generated. A test combustion device (C) consisting of a storage means (5) for storing set values is provided separately from the main combustion device (B), and the excess air ratio of the combustion specifications of the main combustion device (B) is stored. A combustion specification setter (6) adapted to the value stored in the means (5) is provided, and the test combustion device (C) is activated by a test combustion signal prior to the operation of the main combustion device (B). Combustion device.