JPS62280516A - Combution device - Google Patents

Abstract

PURPOSE:To keep an air-fuel ratio in a set value by a method wherein correction control is effected so that the output of a combustion sensor becomes a set value in accordance with the setting condition of the supplying amount of fuel which is controlled by a proportional control valve or the supplying amount of combustion air. CONSTITUTION:A fan control circuit 61 amplifies proportionally the output signal of a water temperature sensor 53 and a reference value obtained from a volume 54 for regulating temperature and controls the amount of conduction for a fan 33 to regulate the temperature of hot-water obtained from a gas water heater 1. A rotating speed detecting circuit 52 detects the rotating speed of the fan 33 to detect the supplying amount of combustion air. A proportional valve control circuit 63 controls the opening ratio of a proportional control valve 45 in accordance with the output of the rotating speed detecting circuit 62 and the output of a thermocouple 52 to control the supplying amount of gas. The opening degree setting circuit 63a of the proportional valve control circuit 63 sets the opening of the proportional valve 45 in accordance with the output of the rotating speed detecting circuit 62 while an opening degree correcting circuit 63b corrects the output of the opening degree setting circuit 63a so that the output of the thermocouple 52 becomes a value set in accordance with the output of the rotating speed detecting circuit 62.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention consists of a proportional system for supplying fuel to a burner +1] a blower for supplying combustion air to a burner; The present invention relates to a combustion device equipped with.

[Conventional technology] Combustion type positive F# equipment, which supplies fuel such as gas or oil to the burner according to the amount of fuel supplied by a proportional control valve, and also supplies combustion air to the burner by a blower. Combustion devices such as heating devices are used.

Conventionally, in this type of device, the amount of fuel supplied by the proportional control valve is set according to the calorific value setting means (for example, temperature setting means) set by the user, and the fuel is supplied to the burner. Air is supplied to the burner, and fuel is combusted in the burner. At this time, the combustion air supplied by the feeder 1!111 is in the shape of the burner flame! It is controlled according to the output of a combustion sensor (e.g. thermocut) that detects &.

Problem 1 to be Solved by the Invention However, in conventional combustion devices, as mentioned above, the circuit for controlling the proportional control valve and the circuit for controlling the blower are each independent and separate circuits. For example, when the calorific value setting means is changed, the opening degree of the proportional control valve changes quickly in response to the change in the calorific value setting means. The combustion sensor detects changes in the flame due to changes in temperature, and the blower of the blower is changed based on the change in the output of the combustion sensor. Therefore, the blower has a problem in that the responsiveness of the blower to changes in the light iam setting means is very poor. Ta.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to quickly match the supply of fuel by the proportional control valve m and the amount of combustion air supplied by the blower by applying changes in the calorific value setting means. An object of the present invention is to provide a combustion device that can maintain the air-fuel ratio at a preset value.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a burner, a proportional control valve for supplying fuel to the burner, and an air blower for supplying air for combustion to the burner. a combustion sensor that detects the combustion state of the burner; a calorific value setting means; and, depending on the setting state of the calorific value setting means, between the supply of fuel by the proportional control valve or the supply of combustion air by the blower. between the first control circuit that performs one of the controls, the setting state of the calorific value setting means, or the amount of fuel supplied by the proportional control valve controlled by the first control circuit;
According to the setting state of one of the combustion air supply by the method ff1i, the other of the fuel supply amount by the proportional control valve or the combustion air supply amount by the ventilation mode is controlled. and a second control circuit, wherein the output of the combustion sensor is controlled by the calorific value setting means, the amount of fuel supplied by the proportional control valve controlled by the first control circuit, or the output of the combustion sensor. Law J! It +1
The amount of fuel supplied by the proportional control valve or the manner of air blowing controlled by the second control circuit is controlled by the second control circuit so that the amount of fuel supplied by the proportional control valve becomes a preset value according to the setting state of one of the amounts of combustion air supplied by The technical means is to carry out corrective control of the other of the combustion air supply (1).

[Operations and Effects of the Invention] In the present invention having the above configuration, the first control circuit controls the supply of fuel by the proportional control valve or the supply of combustion air by the feeding locus, depending on the setting state of the calorific value setting means. By controlling one of them, when the calorific value setting means is changed, one of the two quickly changes in accordance with the change in the calorific value setting means. Further, the second control circuit controls the other of the fuel supply 1 by the proportional control valve or the combustion air supply amount by the method I'll according to the setting state of the calorific value setting means or one of them. When the calorific value setting means is changed, the other quickly changes in response to a change in the calorific value setting means or one. As a result, the amount of fuel supplied by the proportional control valve and the amount of combustion air supplied by the blower are set to appropriate values almost simultaneously in accordance with changes in the calorific value setting means.
The calorific value can be changed instantly in response to changes in the calorific value setting means, and the flame can always be combusted at an appropriate air-fuel ratio.

Additionally, if the flame is not combusted at an appropriate air-fuel ratio, the output of the thermocouple will be a value different from the value preset according to one side, but the second control circuit will change the output of the combustion sensor according to one side. The amount of gas supplied to the burner or the amount of combustion air supplied to the burner is always corrected to an appropriate value, and the flame is adjusted to a preset value. is combusted at an appropriate air-fuel ratio.

[Example] Next, an example in which the present invention is applied to a gas water heater will be described based on the drawings.

FIG. 2 shows a schematic diagram of a gas water heater.

This gas water heater 1 includes a combustion section 3 equipped with a heat exchange section 2,
It consists of a gas supply path 4 and an electronic control circuit 5.

The combustion section 3 includes a combustion chamber 32 equipped with a ceramic surface-combustion burner 31, and a blower 33 that is attached to the lower part of the combustion chamber 32 and supplies air for combustion to the burner 31.
and an exhaust port 35 provided above the combustion chamber 32 to exhaust the combustion gas combusted by the burner 31. The heat exchange section 2 is composed of fins 21 and a water supply pipe 22 that increase heat exchange efficiency, and is arranged between a burner 31 and an exhaust port 35 to burn water sent from upstream of the water supply pipe 22. It exchanges heat with the combustion gas in the chamber 32 and flows out as hot water.

The gas supply path 4 is provided on the upstream side of a gas jet nozzle 41 that discharges gas upstream of the burner 31 and a gas supply pipe 42 that supplies gas to the gas jet nozzle 41, and is opened and closed by energization and a non-oil dragon. a governor valve 44 provided on the downstream side of the on-off valve 43 to adjust the flow rate of gas; and a governor valve 44 provided on the downstream side of the governor valve 44,
Connoisseur? Proportional control valve 45 whose opening ratio varies according to 1ffi
It consists of

The electronic control circuit 5 includes a spark electrode 51 that emits sparks on the upper surface of the burner 31 during ignition, a thermocouple 52 that is a combustion sensor that detects the oxygen supply state of the flame above the burner 31, and a water supply pipe 22 of the heat exchange section 2. A water temperature sensor 53 attached to the outflow section to detect the water temperature, a temperature control volume 54 operated by the user to set the temperature of the water flowing out from the water supply pipe 22 of the heat exchange section 2, a blower 33, an on-off valve 43, a proportional It drives and controls the control valve 45 and the like.

Next, control of the frontage ratio of the proportional control valve 45 and control of the supply of combustion air by the blower 33 will be explained based on the block diagram shown in FIG.

By comparing and amplifying the output signal from the water temperature sensor 53 and the reference value obtained by the temperature body volume 54 and controlling the energization fog to the blower 33, the temperature of the lagoon obtained from the gas water heater 1 is Sl! A blower control circuit (temperature adjustment circuit) 61 that performs the first section; a rotation speed detection circuit 62 that detects the amount of combustion air supplied by the blower 33 by detecting the rotation speed of the blower 33; A proportional valve control circuit 63 is provided, which controls the opening ratio of the proportional control valve 45 according to the output of the circuit 62 and the output of the thermocouple 52, and controls the amount of gas supplied.

The proportional valve control circuit 63 includes an opening setting circuit 63a that sets the opening of the proportional control valve 45 according to the output of the rotation speed 1 detection circuit 62, and an opening setting circuit 63a that sets the opening of the proportional control valve 45 according to the output of the rotation speed 1 detection circuit 62. The opening correction circuit 63b corrects the output of the opening setting circuit 63a to a value set according to the output of the opening setting circuit 63a.

Next, one embodiment of the rotational speed detection circuit 62 will be described using FIG. 3.

The blower 33 of this embodiment uses a brushless motor that uses a ball element 33c to detect the rotational position of a permanent magnet 33b attached to a drive shaft 33a. This rotational speed detection circuit 62 includes a signal generation section 62a consisting of a permanent magnet 33b, a Hall element 33c, and coils C01 to CO4, an analog switch section 62b, a decoder 62c, and a voltage conversion section 6.
It consists of 2d. The output voltage (2) of the voltage converter 62d changes proportionally to a predetermined voltage according to the rotational speed N of the blower 33, as shown in FIG.

Further, as shown in FIG. 5, the opening degree setting circuit 63a of the proportional valve control circuit 63 first determines the amount of current A to be applied to the proportional control valve 45 according to the output voltage V output from the rotational speed detection circuit 62. ing.

Then, the opening correction circuit 63b adjusts the output voltage ff1v of the thermocouple 52 proportionally so that it becomes a value set according to the output voltage ■ output from the rotational speed detection circuit 62, as shown in FIG. The amount of electricity supplied to the control valve 45 is corrected and controlled.

The gas water heater 1 of this embodiment has an electronic υ1tl as described above.
By providing the temperature adjustment volume 54, when the user desires to change the temperature of the water supplied from the gas water heater 1 by operating the temperature adjustment volume 54, the temperature adjustment volume 54 is provided.
Because the reference voltage output by the temperature control volume 54 quickly changes with respect to the output of the water temperature sensor 53 due to a change in Air blow +g%33
change the rotation speed of. When the rotational speed of the air blower 33 changes as described above, the output voltage V of the rotational speed detection circuit 62 changes, so the opening setting circuit 63a changes the rotational speed of the proportional control valve 4.
The energization ff1A to 5 is set according to FIG. In other words, when the operator operates the temperature control volume 54, the rotational speed of the blower 33 and the opening degree of the proportional control valve 45 change almost simultaneously, so that the temperature desired by the operator is lower than that of the gas water heater 1. supplied quickly. Also, at this time, since the opening degree of the proportional control valve 45 and the rotational speed of the retractor 13 change almost simultaneously, the ratio between the amount of combustion air supplied by the blower 33 and the amount of gas supplied by the proportional control valve 45 is always constant. The flame is kept at an appropriate value so that the flame always burns at the correct air/fuel ratio.

In addition, due to changes in the components of the supplied gas, the flame may not burn at an appropriate air-fuel ratio, or the flow resistance of the combustion air inlet, outlet, etc. may increase, etc.
There is a possibility that the combustion air set according to the opening degree of the combustion air is not supplied, and the flame does not burn at an appropriate air-fuel ratio.

In this case, for example, in FIG. 6, the rotational speed detection circuit 6
When the value of the output voltage V of 2 is A1 and the value of the output voltage mV of the thermocouple 52 is A2, since it is a gas ridge, the opening degree of the proportional control valve 45 is reduced and the output voltage mV of the thermocouple 52 is set in advance. Is the communication to the proportional control valve 45 so that 1iA3 is obtained? Correct the value of HffiA.

Further, when the value of the output voltage (■) of the rotational speed detection circuit 62 is A1 and the value of the output voltage mV of the thermocouple 52 is A4, the opening degree of the proportional control valve 45 is increased because the gas is lean, and the thermocouple 52 is The value of energization ff1A to the proportional f, 11 m valve 45 is corrected so that the output voltage mV becomes 3 to a preset value. As a result, the flame is always combusted at an appropriate air-fuel ratio.

On the other hand, the water temperature sensor +j-53 constantly monitors the temperature of the hot water supplied from the gas water heater 1, and adjusts the temperature so that the temperature detected by the water temperature sensor 53 and the temperature set by the temperature 'J4' By controlling the proportional valve control circuit 63 by the blower control circuit 61, the opening degree of the proportional control valve 45 is corrected and controlled at a speed approximately corresponding to the temperature detection speed of the water wetness sensor 53, and the gas is supplied from the gas IT device 1. The temperature of the hot water is corrected to the temperature set by the temperature adjustment volume 54.

Note that the blower control circuit 61 is provided with, for example, one
This is provided to cancel the input from the thermocouple 52 for 0 seconds to prevent malfunction of the air-fuel ratio control by the thermocouple 52 at the time of ignition.

In this embodiment, the means for detecting the rotational speed of the blower 33 includes:
Although an example in which detection is performed using the Hall element 33c is shown, detection may be performed using a rotary encoder, a resolver, a frequency generator, or the like.

In addition, in this embodiment, send J! Although an example of detecting the rotation speed of the blower 33 as a means for detecting the supply status of combustion air by the It 4133 has been shown, it is also possible to detect the rotation speed of the blower 33 downstream of the blower 33.
! The wind pressure of 1g133 is detected by a pressure sensor or the like, and the blower 33 is
The supply source of combustion air may also be detected. Note that when detecting the supply m of combustion air based on the amount of current supplied to the air blower R33, a delay circuit is provided on the input side or output side of the proportional valve control circuit 63, and the air blower R33 changes smoothly.
The opening degree of the proportional control valve 45 may be varied during the rotational speed change.

FIG. 7 shows a second embodiment of the present invention.

The electronic control circuit 5 of this embodiment is a proportional valve control circuit (temperature adjustment circuit) that controls the amount of electricity supplied to the proportional control valve 45 based on the outputs of the water temperature sensor 53 and the temperature adjustment volume 54.
71, and a blower control circuit that detects the energization 1 supplied to the proportional control valve 45 from the proportional valve control circuit 71 and controls the amount of energization of the air blower 33 according to the energization 1fi and the output of the thermocouple 52. 72.

This blower control circuit 72 is connected to the proportional valve control circuit 71.
As shown in FIG. 8, the rotation speed setting circuit 72a sets the amount of current to the blower 1j133 according to the output of A rotational speed correction circuit 72 corrects the output of the rotational speed setting circuit 72a so that the output value becomes the specified value.
It consists of b.

In this embodiment, the opening degree of the proportional control valve 45 is detected based on the amount of current supplied to the proportional control valve 45, but it can also be detected by detecting the displacement m of the valve body of the proportional control valve 45. It's okay.

FIG. 9 shows a third embodiment of the present invention.

In the second embodiment described above, when the temperature adjustment volume 54 is operated, the amount of current applied to the blower 33 and the amount of current applied to the proportional control valve 45 change almost simultaneously. The response speed of the proportional control valve 45 changes more gradually than the response speed of the proportional control valve 45. Therefore, if the amount of electricity supplied to the blower 33 and the proportional control valve 45 is changed at the same time, the proportional change will occur immediately after the temperature adjustment volume 54 is operated. In some cases, the rotation speed of the blower 33 does not follow the change in the opening degree of the control valve 45, and the air-fuel ratio changes, although this is not the case in the past. Therefore, in this embodiment, a delay circuit 73 is provided on the input side of the proportional control valve 45 to delay the input signal. This results in
Since the opening degree of the proportional control valve 45 can be changed while the rotational speed of the blower 33 changes gradually,
Compared to the embodiment described above, the change in the air-fuel ratio immediately after operating the temperature control volume 54 can be suppressed to a smaller level.

FIG. 10 shows a fourth embodiment of the present invention.

The electronic control circuit 5 of this embodiment compares and amplifies the output signal from the water temperature sensor 53 with a reference value obtained by the temperature control volume 54, adjusts the temperature of the lagoon obtained from the gas water heater 1, and adjusts the temperature of the lagoon obtained from the gas water heater 1. A calorific value setting circuit (temperature adjustment circuit) 81 is a calorific value setting means for setting the combustion amount (calorific value) of gas at step 31, and the amount of electricity supplied to the proportional control valve 45 is determined by the output of the calorific value setting circuit 81. , and a blower control circuit 83 that controls the amount of electricity supplied to the blower 33 according to the output of the heat value setting circuit 81 and the output of the thermocouple 52.

And this sending J! 11 control circuit 83 sends I! according to the output of the heat generation setting circuit 81. As shown in FIG. 11, the rotation speed setting circuit 83a that sets the amount of current supplied to the engine 33 and the output voltage mV of the thermocouple 52 are set according to the output β of the heat generation amount setting circuit 71. and a rotational speed correction circuit 83b that corrects the output of the rotational speed setting circuit 83a so that the rotational speed setting circuit 83a is corrected.

In addition, in this embodiment, sending I! Although the air-fuel ratio was corrected by correcting the In control circuit 83, the air-fuel ratio may also be controlled by correcting the proportional valve control circuit 82. In addition, a delay circuit is provided on the input side or output side of the proportional valve control circuit 82, so that the feed + [
The opening degree of the proportional control valve 45 may be changed in the middle of the change in rotational speed of 33.

Further, in the above embodiment, an example was shown in which the present invention was applied to a water heater, but the present invention may be applied to other combustion devices such as a heating device.

Furthermore, the present invention may be applied to other combustion devices that use other fuels such as kerosene.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the control circuit according to the present invention, Fig. 2 is a schematic diagram of a gas water heater, Fig. 3 is an electric circuit diagram of the rotation speed detection circuit, and Fig. 4 is the rotation speed and rotation speed of the blower. A graph showing the relationship with the output of the rotation speed detection circuit, Figure 5 is a graph showing the energization base of the proportional control valve set for the output of the rotation speed detection circuit, and Figure 6 is a graph showing the relationship with the output of the rotation speed detection circuit. A graph showing the appropriate output value of the set thermocouple, Fig. 7 is a block diagram of the control circuit showing the second embodiment of the present invention, and Fig. 8 shows the thermocouple set for the output of the proportional valve control circuit. 9 is a block diagram of a control circuit showing a third embodiment of the present invention, FIG. 10 is a block diagram of a control circuit showing a fourth embodiment of the present invention, and FIG. 11 is a block diagram of a control circuit showing a fourth embodiment of the present invention. It is a graph showing the appropriate output value of a monomocouple set with respect to the output of the heating water setting circuit. In the diagram 1... Gas water heater 31... Burner 33.
...Blower 42...Gas supply piping 45...Proportional control valve 52...Thermocouple 53...Water temperature sensor 54...Saltness adjustment volume 61...
Blower control circuit 62... Rotation speed detection circuit 63.
...Proportional valve control circuit Fig. 6 Thermocouple pressure "I1. Pressure mV Fig. 4 Rotational speed line of feed and lR, N Fig. 5 Amount of current flowing through Jf, IJm valve A Fig. 8 Fig. 11vA

Claims (1)

[Scope of Claims] 1) A burner, a proportional control valve that supplies fuel to the burner, a blower that supplies combustion air to the burner, and a combustion sensor that detects the combustion state of the burner; a first control circuit that controls either the amount of fuel supplied by the proportional control valve or the amount of combustion air supplied by the blower according to the setting state of the calorific value setting means; , depending on the setting state of the calorific value setting means, or the setting state of one of the amount of fuel supplied by the proportional control valve controlled by the first control circuit or the amount of combustion air supplied by the blower, and a second control circuit that controls the other of the amount of fuel supplied by the proportional control valve or the supply of combustion air by the blower, and the second control circuit is configured to control the output of the combustion sensor according to the amount of fuel supplied by the blower. A value set in advance according to a setting state of one of a calorific value setting means, an amount of fuel supplied by the proportional control valve controlled by the first control circuit, and an amount of combustion air supplied by the blower. A combustion apparatus characterized in that correction control is performed on the other of the amount of fuel supplied by the proportional control valve controlled by the second control circuit or the amount of combustion air supplied by the blower. 2) The combustion device according to claim 1, wherein the combustion sensor is a thermocouple that detects the temperature of the flame and the state of air supply to the flame. 3) The combustion apparatus according to claim 1 or 2, wherein the first control circuit is a blower control circuit that controls the amount of electricity supplied to the blower. 4) The combustion apparatus according to claim 3, wherein the amount of combustion air supplied by the blower is detected from the rotational speed of the blower. 5) The combustion apparatus according to claim 1 or 2, wherein the first control circuit is a proportional valve control circuit that controls the amount of electricity supplied to the proportional control valve. 6) The combustion device according to claim 5, wherein the amount of fuel supplied by the proportional control valve is detected from the amount of current supplied to the proportional control valve from the proportional valve control circuit.