JP3156318B2 - Combustion control device - Google Patents

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 used for a hot oil heater or the like.

[0002]

2. Description of the Related Art Conventionally, this type of oil-fired heater is shown in FIG.
7 are configured as shown in FIG. That is, in FIGS. 5 and 6, reference numeral 1 denotes a fixed tank for holding liquid fuel, and a detachable cartridge tank 2 is disposed on the fixed tank. A pump 3 is provided on the upper surface of the fixed tank 1. Liquid fuel from the pump 3 is supplied to a combustion unit 4, and combustion exhaust gas generated there is guided upward by a combustion tube 5. The combustion section 4 is provided with a flame rod type combustion sensor 6 for detecting a combustion state by flowing a current between electrodes placed in the combustion flame and measuring the amount of the current. The combustion cylinder 5 is covered with a duct 7 and mixes the indoor air flow from a convection blower 8 disposed rearward with the above-mentioned combustion exhaust gas to generate hot air. Further, as shown in FIG. 7, the combustion section 4 is controlled by a combustion control section 9 based on the output of the combustion sensor 6 and the like.

[0003]

However, in the above-mentioned conventional construction, the combustion flame is shaken by the discharge of the liquid fuel from the pump 3 and the balance of the combustion air, and the combustion flame becomes instantaneously unstable due to the disturbance of the surroundings. Such as,
Although the combustion is not totally abnormal, the output of the combustion sensor 6 instantaneously drops below the partition value provided at a position lower than the normal level, and the combustion control unit 9 stops the combustion and stops the operation of the equipment. There were problems such as the occurrence of a cutting phenomenon.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to prevent premature disconnection due to disturbances in the surroundings and to prevent repetition of ignition and extinguishing caused by abnormal combustion to ensure safety. Things.

[0005]

In order to achieve the above object, the present invention first determines whether or not the output from the combustion sensor is abnormal.
A determination unit for determination and the number of abnormalities from the determination unit are stored.
Storage unit, a predetermined number of times set in advance and abnormality of the storage unit
The safety control part consisting of a number of malfunctions check unit for comparing the count provided by the safety control unit of the first aspect of the invention, the abnormality frequency confirmation
The combustion control unit outputs the combustion continuation signal until the comparison result reaches the specified number of times, and outputs the combustion stop signal to the combustion control unit when the comparison result reaches the specified number of times. When the output is output, if a specified number of times occur within a predetermined time from the first abnormality detection output, a combustion stop signal is output to the combustion control unit as abnormal, and
When a specified number of abnormality detection outputs have been generated beyond the predetermined time since the first abnormality detection output, a combustion continuation output is output to the combustion control unit, and at the same time, any of the abnormality detection outputs generated from the first time to the predetermined time is output. With the abnormality detection output as a starting point, the counting of the abnormality detection output is repeated from the beginning.

[0006] Further, the safety control section of the third invention is a safety control section of the first invention.
When the abnormality detection output is issued to the safety
A timer count unit is added to start the operation. When an abnormality detection output is output, the timer count starts from the first abnormality detection output, and when a specified number of abnormality detection outputs occur within a predetermined time, it is determined as abnormal to the combustion control unit. In addition to outputting the combustion stop signal, if there is no specified number of abnormality detection outputs within the predetermined time from the first abnormality detection output, the timer count is reset and the number of abnormality detections is reset.
Then, the next abnormality detection output is set as the first abnormality detection output.

[0007]

According to the first aspect of the present invention, the combustion is continued until the generation of the abnormality detection output from the combustion sensor exceeds a specified number of times, so that the premature stop can be prevented. To stop. Also the second
According to the third configuration, the combustion is stopped only when the abnormality detection output reaches a specified number of times within a predetermined time. In this case, the combustion can be stopped only to prevent the occurrence of soot, CO, odor, etc. due to repetition of flashback combustion or the like, and at other times, the combustion can be continued to improve the reliability.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the accompanying drawings, in which the same parts as those of the prior art are denoted by the same reference numerals, description thereof will be omitted, and different parts will be described.

In FIG. 1, reference numeral 10 designates a safety control for judging whether or not the output from the combustion sensor 6 is abnormal, and sending a predetermined output to the combustion control section 9 in the case of abnormality to cause the combustion section 4 to burn and stop. Department. This safety control unit 10 is shown in FIGS.
The configuration is as described in the flowchart of FIG. 4, and the configuration will be described below together with the operation.

The case of the invention shown in FIG. 2 will be described.
First, when the operation switch is turned on at 11, an ignition operation is performed at 12, and when ignition is detected at 13, the operation of the safety control unit 10 starts. That combustion flame rod output from the sensor 6 (satiate than FR) constitutes a determination unit for determining whether or not an abnormality lower limit at 14, and stores the Re this <br/> in the storage unit 15 if abnormal To go. Then, the stored number of FR abnormalities is determined to be a specified number of times, for example, 3 times, and 16 abnormal times are confirmed.
Check in the section .

Here, if the number of FR abnormalities is less than three, an instruction to continue combustion is issued. That is, when the FR abnormality occurs due to, for example, flashback or the like and the combustion in the combustion section is stopped, 17
If the operation switch has not been turned off, the process returns to step 12 to perform the ignition operation, and returns to the operation of determining whether or not FR is at the abnormal lower limit value, and thereafter the same operation is repeated.

On the other hand, when the above operation is performed and the number of FR abnormalities becomes equal to or more than the specified number, a stop output is output to the combustion control unit to stop the combustion.

That is, in the present invention, even if the flame rod output is abnormal, the combustion is continued up to the specified number of times, and the combustion is stopped when the flame number exceeds the specified number of times. The combustion can be continued to prevent premature termination.If the number of times exceeds the specified number, the flame rod output may not be abnormal but may be due to some cause. The combustion can be stopped.

Next, the invention shown in FIG. 3 is an improvement of the previous invention. That is, if the FR abnormality reaches the specified number of times within the predetermined time, the combustion is stopped, but even if there is a specified number of abnormalities beyond the predetermined time from the first FR abnormality, for example, the third FR abnormality in the above example, If the time exceeds the predetermined time, clear the number of FR abnormalities up to that time and perform the third FR
It is checked whether or not the specified number of FR abnormalities occur again within a predetermined time after the abnormality, and the combustion is continued until the specified number of occurrences occurs within the predetermined time. That is, 1
When the FR abnormality is detected in 4, the timer for counting a predetermined time is driven in 18 and the same operation as above is repeated until the time indicated by 19 is reached, and the number of FR abnormalities must reach the specified number by the time up (within the predetermined time). If this is the case, continue burning. If the time is up before the number of FR abnormalities reaches the specified number, the FR abnormal number is stored starting from the first FR abnormality (this may be any one of the FR abnormalities within the specified number). Is cleared at 20, the timer is initialized again, and the operation starting from the timer drive is repeated to continue the combustion.

On the other hand, if the number of FR abnormalities reaches the specified number within the predetermined time, the combustion is stopped.

Therefore, in the case of the present invention, it is possible to prevent a combustion stoppage in which the FR is temporarily abnormal due to disturbance or the like and reaches a specified number of times, even though the combustion is not abnormal after prolonged combustion. In the case where abnormal combustion occurs in a short time such as flashback and FR abnormality repeatedly occurs, combustion can be reliably stopped.

Next, the invention shown in FIG. 4 is a further improvement of the previous invention. That is, if the FR abnormality reaches the specified number of times within the predetermined time, the combustion is stopped. At the same time when the FR abnormality is cleared, the timer count is also reset at 22 to return to the initial state and continue the combustion. That is, a timer for counting a predetermined time is driven, and the same operation as above is repeated until the time is up.
If the abnormal number does not reach the specified number by the time-up (within a predetermined time), the combustion is continued as it is. And FR
If the time is up before the number of abnormalities reaches the specified number, the storage of the number of FR abnormalities is cleared, the timer is stopped and initialized, and combustion is continued under the same conditions as before the occurrence of the FR abnormality.

On the other hand, if the number of FR abnormalities reaches the specified number within the predetermined time, the combustion is stopped.

Therefore, in the case of the present invention, the same effect as that of the second invention can be obtained, and the timer for counting a predetermined time can be shortened, so that the circuit configuration can be simplified.

Although the specified number of FR abnormalities is not specified in the above example, the specified number of times is set to, for example, two times, and the predetermined time is set to be slightly longer than the expected span of the phenomenon of abnormal combustion. If this is done, abnormal combustion that repeats in a short time, such as the above-mentioned flashback, can be minimized.Frequency may temporarily become abnormal due to external disturbances, etc. In this case, it is possible to reliably prevent combustion stoppage,
In addition, the structure is simplified and more effective. Further, in the above-described example, the first counting of the predetermined time is started from the first FR abnormality, but this may be started from the start of ignition.

[0021]

As described above, according to the combustion control device of the present invention, it is possible to prevent a premature stop due to a surrounding disturbance or the like, and to reduce the flame rod output to an abnormal lower limit value.
In the event of an unstable combustion state, such as below or above, combustion can be stopped to ensure safety. In the second and third aspects of the present invention, the combustion is continued for a longer period of time, and even if a disturbance in the surroundings occurs during the process, the combustion is continued without stopping the combustion. Only when the combustion stops,
Trust is high.

[Brief description of the drawings]

FIG. 1 is a block diagram of a combustion control device according to an embodiment of the present invention.

FIG. 2 is a flowchart of the control device.

FIG. 3 is a flowchart of a control device according to another invention.

FIG. 4 is a flowchart of a control device according to another invention.

FIG. 5 is a cross-sectional view of a hot air heater using the present invention and a conventional combustion control device.

FIG. 6 is a front view of the hot air heater.

FIG. 7 is a block diagram showing a conventional hot air heater control device.

[Explanation of symbols]

 4 Combustion unit 6 Combustion sensor 9 Combustion control unit 10 Safety control unit

Claims (3)

(57) [Claims] 1. A combustion section for burning fuel, a combustion sensor for detecting a combustion state of the combustion section, a combustion control section for controlling combustion in the combustion section, and a combustion sensor based on an output from the combustion sensor.
A safety control unit that outputs a combustion stop signal to the combustion control unit
The safety control unit has an abnormal output from the combustion sensor.
And a determination unit for determining whether or not the number of abnormalities from the determination unit
A storage unit for storing a predetermined number of times set in advance and the storage
The unit consists of a unit for checking the number of abnormalities that compares the number of abnormalities in the unit.
A combustion control device that outputs a combustion continuation signal until the comparison result of the abnormal number confirmation unit reaches a specified number, and outputs a combustion stop signal when the comparison result reaches the specified number. 2. A combustion unit for burning fuel, a combustion sensor for detecting a combustion state of the combustion unit, a combustion control unit for controlling combustion of the combustion unit, and a control unit for determining whether an output from the combustion sensor is abnormal. When the determination is made and the abnormality detection output is output, a combustion stop signal is output to the combustion control unit as abnormal when the specified number of occurrences occur within a predetermined time from the first abnormality detection output, and the predetermined abnormality detection output is output from the first abnormality detection output. If a specified number of abnormality detection outputs are generated over a period of time, the combustion continuation output is output to the combustion control unit, and at the same time, any of the abnormality detection outputs generated from the first time to the predetermined time is used as a starting point. A combustion control device including a safety control unit that repeats counting of an abnormality detection output from the beginning. 3. A combustion section for burning fuel, a combustion sensor for detecting a combustion state of the combustion section, a combustion control section for controlling combustion in the combustion section, and a combustion sensor based on an output from the combustion sensor.
A safety control unit that outputs a combustion stop signal to the combustion control unit
The safety control unit has an abnormal output from the combustion sensor.
And a determination unit for determining whether or not an abnormality is detected from the determination unit.
Timer counting section that starts timing when force is applied
A storage unit for storing the number of abnormalities from the determination unit;
Compare the specified number of times and the number of abnormalities in the storage unit
It consists of an abnormality count confirmation unit, and compared with the abnormality count confirmation unit.
The result is a predetermined time from the start of timing by the timer count unit.
If the specified number of times is reached within
If the specified number of times has not been reached within the predetermined time, combustion is continued.
Then reset the timer count section and the storage section
A combustion control device that detects abnormalities from the initial state .