JPH0854117A - Combustion controller for heater - Google Patents

Abstract

PURPOSE:To obtain the combustion controller for a heater which can stably burn without red flame, flame lifting, etc., even when the number of revolutions of a combustion motor temporarily comes out of comes out of the predeter mined range of the maximum value and the minimum value. CONSTITUTION:Data memory means 9 in a microcomputer 6 so controls as to hold out-of-predetermined fuel supply quantity data 18 for burning out of predetermined maximum and minimum values, to hold an air fuel ratio constant by following the fuel supply quantity even when the number of revolutions of a combustion motor 2 is out of the range of predetermined maximum and minimum values, to stably burn without red flame and lifting of flame, etc., and to forcibly fire extinguish when the combustion is continued out of the predetermined range for a predetermined time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion control device for a heater such as an oil fan heater, and more particularly to control of fuel and air during combustion.

[0002]

2. Description of the Related Art Conventionally, an air supply amount is controlled at a predetermined supply amount corresponding to a combustion amount of a heater, and when the air supply amount is changed, the air supply amount is not changed at once but for a predetermined time. By performing the control step by step every time, the harmful effects such as the red fire and the lifting of the flame due to the collapse of the air-fuel ratio have been prevented.

FIG. 5 is a schematic sectional view of a combustion section of a conventional heating device of this kind. In FIG. 5, 1 is a combustor, 2 is a combustion motor for sending combustion air to the combustor 1, and 3 is the above-mentioned. This is an electromagnetic pump that sends liquid fuel to the combustor 1, and supplies combustion air and liquid fuel to the combustor 1 in a well-balanced manner by the combustion motor 2 and the electromagnetic pump 3 so as to keep the air-fuel ratio constant. ing.

FIG. 6 is a block diagram of combustion control of a conventional heater. Reference numeral 1 is a combustor, 6 is a microcomputer as control means, and 11 is a combustion motor for sending combustion air to the combustor 1. The air supply means, 8 is a combustion motor control means for controlling the air supply means 11, and 10 is predetermined air supply amount data necessary for determining the air supply amount, which is predetermined according to the combustion amount. ,
The predetermined air supply amount data 10 is held in the data storage means 9 in the microcomputer 6. Reference numeral 16 is fuel supply means such as an electromagnetic pump for sending fuel to the combustor 1, 14 is pump control means for controlling the fuel supply means 16, and 15 is predetermined fuel supply amount data for determining the fuel supply amount. Is determined in accordance with the air supply amount so that it does not collapse and is held in the data storage means 9 in the microcomputer 6.

FIG. 7 is a time chart of the number of revolutions of the conventional combustion motor and the fuel supply amount of the electromagnetic pump. The combustion amount changes and the number of revolutions of the combustion motor changes from low rotation R _L to high rotation R _H. In this case, the red fuel and the lifting of the flame are prevented by gradually changing the value without changing all at once and by changing the predetermined fuel supply amount stepwise according to the number of revolutions. Similarly, when the rotation speed is changed from the high rotation speed R _H to the low rotation speed R _L , the rotation speed is also changed stepwise.

[0006]

[SUMMARY OF THE INVENTION However, in the conventional configuration, the rotational speed of the combustion motor changes changes from low rotation R _L to the high rotation R _H and the high rotation R _H to low rotation R _L At this time, if this rotational speed temporarily deviates from the specified maximum and minimum range due to overshoot or undershoot, or if it deviates due to an increase or decrease in the power supply voltage, the air-fuel ratio collapses and red There were problems such as the effects of fire and lifting of flames. Also, if the rotation speed deviates from the range between the predetermined maximum value and the minimum value due to an abnormality in the combustion motor, the combustion motor may continue combustion in a state where the air-fuel ratio has collapsed and the abnormality has occurred. There was a problem.

The present invention solves the above problems. A first object of the present invention is to provide a red color when the supply amount of combustion air is temporarily out of a predetermined maximum and minimum range. It is to prevent lifting of fire and flame.

A second object is to improve safety and reliability when the value is out of the range of the predetermined maximum value and minimum value.

[0009]

A combustion control device for a heater according to the present invention comprises a combustor, fuel supply means for supplying fuel to the combustor, and air supply means for supplying combustion air to the combustor. And a combustion amount determining means for calculating the combustion amount from the indoor temperature and the set temperature, and a predetermined air supply amount data which is predetermined corresponding to the combustion amount and the air-fuel ratio is kept constant according to the air supply amount. Data storage means for holding predetermined fuel supply amount data determined to be stored, combustion motor control means for controlling the air supply amount based on the predetermined air supply amount data held in the data storage means, and the data storage A pump control means for controlling the fuel supply amount based on the fuel data held in the means, and a detection means for detecting the air supply amount by the air supply means are provided, and the data storage means has a predetermined air supply amount. When the fuel supply amount temporarily deviates from the range of the maximum value and the minimum value, the fuel supply amount follows the air supply amount and holds the non-prescribed fuel supply amount data for combustion outside the predetermined range, and the air supply amount is temporarily changed. When the detection means detects that the fuel supply amount is out of the predetermined range, the pump control means selects the fuel supply amount from the non-predetermined fuel supply amount data and causes it to follow.
The air-fuel ratio is controlled so as to be kept constant.

Further, when the state in which the air supply amount is out of the range between the predetermined maximum value and the minimum value is detected by the detection means for a certain period of time, the control is performed to forcibly extinguish the fire.

[0011]

According to the combustion control device for the heater of the present invention, even if the air supply amount deviates from the predetermined maximum and minimum values, the fuel supply amount is corrected by an amount commensurate with the air supply amount. The balance of the mixing of the working air and the fuel will not be lost.

When the combustion is continued for a certain period of time outside the range of the predetermined maximum value and the minimum value, the control means forcibly extinguishes the combustion so that the combustion motor is not a temporary phenomenon such as overshoot. Due to an abnormality or the like, combustion will not continue for a long time in a state where the rotation speed deviates from the predetermined maximum and minimum range.

[0013]

【Example】

Example 1. FIG. 1 is a block diagram of a combustion control device showing an embodiment of the present invention. In FIG.
Is a combustion motor, 3 is an electromagnetic pump, 4 is room temperature detecting means,
Reference numeral 5 is a temperature setting means, and 6 is a microcomputer as a control means. Information from the room temperature detecting means 4 and the temperature setting means 5 is input to a combustion amount determining means 7 provided in the microcomputer 6, where a predetermined range is set. The amount of combustion inside is calculated. Based on this combustion amount, the combustion motor control means 8 selects a predetermined air supply amount stored in the data storage means 9 provided in the microcomputer 6 and controls to supply the air amount. The data storage means 9 has non-predetermined fuel supply amount data 18 for keeping the air-fuel ratio constant by following the fuel supply amount when the air supply amount is out of the range of the predetermined maximum value and the minimum value. .

The air supply means 11 is the combustion motor 2
And a combustion motor drive circuit 12. On the other hand, the rotation speed of the combustion motor 2 measured by the rotation speed detection means 13 for measuring the rotation speed of the combustion motor 2 is converted into an air supply amount, and the pump control means 14 stores data based on the air supply amount. Predetermined fuel supply data 1 in means 9
5 is used to control the fuel supply means 16 to send fuel to the combustor 1.

The fuel supply means 16 is composed of the electromagnetic pump 3 and a pump drive circuit 17. Here, when the rotation speed of the combustion motor 2 is temporarily out of the range of the predetermined maximum value and the minimum value due to overshoot or undershoot when the rotation speed shifts, the pump control means 14 stores the data in the data storage means 9. Non-prescribed fuel supply amount data 1 provided
8 is used to control the electromagnetic pump 3 to supply the fuel to the combustor 1 to burn the fuel without destroying the air-fuel ratio.

The combustion amount determining means 7, the combustion motor control means 8 and the pump control means 14 are processed according to the procedure programmed in the microcomputer 6 in advance.
The processing flow of the microcomputer 6 will be described below with reference to the flowchart of FIG. First, in order to know the amount of air supplied to the combustor 1, the rotation speed of the combustion motor 2 is measured by the rotation speed detection means 13 (step 19). next,
It is determined whether or not this rotation speed is within a predetermined maximum value and minimum value range (step 20).

If the rotation speed is within the predetermined range, the fuel supply data corresponding to the rotation speed is selected from the predetermined fuel supply amount data 15 (step 21) and the electromagnetic pump 3 is used by using this data. It is driven to supply fuel to the combustor 1 (step 22). On the other hand, if it is determined in step 20 that the engine speed is outside the range of the predetermined maximum value and the minimum value, the fuel supply data corresponding to the engine speed is selected from the non-predetermined fuel supply amount data 18 (step 23). , The electromagnetic pump 3 is driven using this data.

Next, the relationship between the rotational speed of the combustion motor 2 and the fuel supply amount will be described with reference to the time chart of FIG. In FIG. 3, the combustion amount is changed from the weak combustion state to the strong combustion state. Therefore, when the rotation speed of the combustion motor 2 is changed from the low rotation speed _RL to the high rotation speed _{RH in accordance} with this combustion quantity, the above rotation speed is set. At a predetermined time (T ₀ → T ₁ → T ₂ →
T ₃ ), the rotational speed is gradually changed to a low rotational speed R _L → R ₁ → R ₂ → R ₃ → high rotational speed _RH , and the fuel supply amount is also changed according to the rotational speed to _FL → F ₁ → The state is shown in which F ₂ → F ₃ → F _H is changed stepwise.

Here, the combustion motor 2 does not immediately stabilize at high rotation R _H , and during the period from Ta to Tb, the rotation speed becomes higher than that of high rotation R _{H due} to overshoot (region 24). When the high rotation speed R _H is the maximum value of the predetermined rotation speed, the fuel supply amount such that the air-fuel ratio becomes constant corresponding to the region 24 is not set in the predetermined fuel supply amount data 15. Therefore, from the non-prescribed fuel supply amount data 18, the area 2
The fuel supply amounts F _S1 and F _S2 corresponding to 4 are selected, the fuel is supplied at this supply amount (region 25), and the air-fuel ratio is adjusted even when the rotation speed is outside the predetermined maximum and minimum values. It becomes possible to burn without breaking.

Further, the rotation speed is from high rotation R _H to low rotation R _L
When the low rotation speed R _L is the minimum value of the predetermined rotation speed at the time of shifting to, by similarly selecting the corresponding fuel supply amount from the non-predetermined fuel supply amount data 18 and supplying the same. It is possible to burn without breaking the air-fuel ratio. In this embodiment, the fuel supply amount outside the predetermined maximum value is set to two levels of F _S1 and F _S2 . However, since the fuel can be finely controlled, it is possible to burn with the fuel outside the predetermined range. It is also possible to finely control the air for use in multiple stages or in stages.

When burning outside the predetermined range, for example, when burning above the maximum value, if the combustion is continued continuously for a long time, the temperature of the combustor 1 rises, which is a problem. If burning is enabled only during overshoot, that is, for a short time as in the embodiment, burning can be performed without abnormality. This time may be set in advance in consideration of the margin for the temperature rise of the combustor 1.

Example 2. In the first embodiment, by holding the non-predetermined fuel supply amount data 18, the fuel and the combustion air could be finely controlled even outside the predetermined range. However, by using the timer means of the microcomputer 6, the fuel is out of the predetermined range. When a certain period of time has elapsed after combustion in the engine, a process of forcibly extinguishing the fire can be added to prevent the combustion motor 2 from continuing to burn in a state in which the rotation speed remains out of a predetermined range due to an abnormality or the like. .

The flowchart shown in FIG. 4 shows the second embodiment of the present invention, and the processing of the microcomputer 6 of the second embodiment will be described. First, the rotation speed of the combustion motor 2 is measured (step 19), and then it is determined whether the rotation speed is within a predetermined range (step 20). If it is within a predetermined range, the predetermined fuel supply amount data 15 is used. Electromagnetic pump 3
Is controlled (steps 21 and 22). On the other hand, when it is determined in step 20 that the rotation speed is out of the range between the predetermined maximum value and the minimum value, the pump 3 is driven using the non-predetermined fuel supply amount data 18 until a predetermined time elapses. (Steps 23 and 22). Then, when a certain time elapses outside the predetermined range, the fire is forcibly extinguished. (Step 2
5).

As described above, when the combustion motor 2 continues to operate outside the predetermined range for a certain period of time, the combustion is forcibly stopped, so that overshoot or undershoot occurs when there is a failure or when the rotation speed changes. It is possible to easily determine whether the phenomenon is a temporary phenomenon. In the case of a temporary phenomenon, the combustion is continued as it is, and in the case of a failure, the combustion is automatically stopped after a certain time. Even in the case of a failure, since it is burned at an optimum air-fuel ratio for a certain period of time and then stopped, the safety is high, and since it is not stopped by a malfunction, it is highly reliable.

[0025]

As described above, according to the present invention, since the non-predetermined fuel supply amount data is held, the number of revolutions of the combustion motor deviates from the predetermined maximum and minimum number of revolutions and combustion is performed. Even if the working air becomes excessive or insufficient, the fuel supply amount is made to follow and the air-fuel ratio is maintained constant, so stable combustion can be performed without any adverse effects such as red fire or flame lifting. At the same time, it is possible to provide a heater with good exhaust gas characteristics and high safety.

Further, when the combustion motor continues to burn for a certain period of time in a state where the rotation speed of the combustion motor is out of a predetermined maximum value and minimum value range, the combustion motor is forcibly extinguished to cause abnormalities in the combustion motor. Combustion does not continue in a state where the number of revolutions deviates from the predetermined range, and a safer heater can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram of a combustion control device for a heater showing an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the first embodiment of the present invention.

FIG. 3 is a time chart showing the relationship between the number of revolutions of the combustion motor and the fuel supply amount according to the first embodiment of the present invention.

FIG. 4 is a flowchart for explaining the operation of the second embodiment of the present invention.

FIG. 5 is a schematic cross-sectional view of a combustion section of this kind of heater.

FIG. 6 is a block diagram of a conventional combustion control device for a heater.

FIG. 7 is a time chart showing the relationship between the rotation speed of a conventional combustion motor and the fuel supply amount.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Combustor 6 Microcomputer 7 Combustion amount determining means 8 Combustion motor control means 10 Predetermined air supply amount data 11 Combustion air supply means 14 Pump control means 15 Predetermined fuel supply amount data 16 Fuel supply means 18 Unspecified fuel supply amount data

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoshihiro Kikuchi 800 Iwamatsu, Oshima-cho, Nitta-gun, Gunma Sanryo Electric Co., Ltd. Gunma Factory

Claims (2)

[Claims] 1. A combustor, a fuel supply means for supplying fuel to the combustor, an air supply means for supplying combustion air to the combustor, and a combustion for calculating a combustion amount from a room temperature and a set temperature. Quantity storage means, and data storage that holds predetermined air supply amount data that is predetermined corresponding to the combustion amount and predetermined fuel supply amount data that is determined so that the air-fuel ratio is kept constant according to the air supply amount Means, a combustion motor control means for controlling the air supply amount based on the predetermined air supply amount data held in the data storage means, and a fuel supply based on the predetermined fuel supply amount data held in the data storage means A pump control means for controlling the amount and a detection means for detecting the air supply amount by the air supply means are provided, and the data storage means is such that the air supply amount temporarily deviates from a range between a predetermined maximum value and a minimum value. In the case where the fuel supply amount follows the air supply amount, the non-predetermined fuel supply amount data for combustion outside the predetermined range is held, and the detection means that the air supply amount temporarily deviates from the predetermined range. When it is detected, the pump control means selects the fuel supply amount from the non-predetermined fuel supply amount data and follows the air supply amount to control so as to keep the air-fuel ratio constant. . 2. When the detection means detects a state in which the air supply amount is out of a range between a predetermined maximum value and a minimum value for a certain period of time or more, it is considered that the air supply means is abnormal and the combustion of the combustor is stopped. The combustion control device for a heating machine according to claim 1, wherein: