JPH04288409A - Burner controller - Google Patents

Abstract

PURPOSE:To prevent an object that falls while a man is not present from touching the operation switch starting combustion in a burner in which the combustion is started only by touching the operation switch. CONSTITUTION:When an operation switch 18 is pressed down, the voltage signal changes from H to L. Next, when the hand is off the operation switch 18, the voltage signal changes from L to H. A controller 21 lets the burner start combustion when those two changes in voltage are successively detected.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for combustion machines such as space heaters and water heaters that use gas or kerosene as fuel.

0002

BACKGROUND OF THE INVENTION Conventionally, for example, a control device for a warm air heater uses a tact type operation switch that turns on or off during manual operation, as disclosed in Japanese Patent Publication No. 16393/1983. It's starting to happen. and,
Different voltages are generated when the operation switch is operated and when it is not operated, and the equipment is started and stopped when the voltage changes due to the operation switch.

0003

[Problems to be Solved by the Invention] The control device for the hot air heater described above is easy to use as it can start and stop the device by simply pressing the operation switch, but on the other hand, falling objects etc. Even if someone touched it, the voltage would change depending on the operating switch, and there was a concern that combustion could start while no one was around.

[0004] This invention was made in view of the above-mentioned fact, and in a device that starts and stops combustion using an operating switch that is turned on or off during manual operation, a falling object may strike the operating switch while no one is present. The purpose is to prevent combustion from occurring.

[0005]

[Means for Solving the Problems] The present invention includes an operation switch that is turned on or off during manual operation, and a voltage signal generating means that generates a different voltage signal when the operation switch is operated and when it is not operated. The control means detects the voltage signal of the voltage signal generating means to determine whether or not there is a manual operation, and controls combustion in the burner according to the determination result. The burner is configured to start combustion when a first change in the voltage signal of the signal generating means and a second change in a direction different from the first change are sequentially detected.

Further, in the above-described control device, the control means is configured to stop combustion in the burner when the first change in the voltage signal of the voltage signal generating means is detected during combustion in the burner.

Further, in the above-mentioned control device, the control means has a predetermined period of time from when the first change in the voltage signal of the voltage signal generating means is detected to when the second change is detected during combustion stoppage of the burner. In the above cases, the system is configured to perform error processing.

Furthermore, the present invention provides an operating switch that is turned on or off during manual operation, and a voltage that generates a first voltage signal and a second voltage signal when the operating switch is operated and not operated, respectively. The control means detects the voltage signal of the voltage signal generation means, determines whether manual operation is being performed, and controls combustion in the burner according to the determination result. When the first voltage signal is detected during the combustion stop, pre-purge in the burner is started, and when the second voltage signal is detected at the end of the pre-purge or before the end of the pre-purge, combustion in the burner is started, and when the pre-purge ends, the burner starts pre-purging. Alternatively, when the first voltage signal is detected before the end of pre-purge, combustion in the burner is prohibited.

[0009]

[Operation] In the control device for a combustion machine according to claim 1, when the operation switch is lightly pressed by hand, the voltage signal of the voltage signal generating means changes from the voltage signal during non-operation to the voltage signal during operation (first change of). Next, when the operation switch is released, the voltage signal of the voltage signal generating means changes from the voltage signal during operation to the voltage signal during non-operation (second change). At this point, the control means initiates combustion in the burner.

[0010] In this way, since the control means starts combustion when it sequentially detects the first voltage change and the second voltage change of the voltage signal generating means, even if a falling object touches the operation switch, There is no need to worry about combustion starting when no one is around.

[0011] In the control device according to the second aspect of the invention, combustion can be quickly stopped by simply pressing the operation switch lightly, which is excellent in safety.

In the control device of the third aspect, when an object falls and touches the operation switch, causing a first change in the voltage signal, an error process is performed when this state continues for a predetermined period of time, and the operation is stopped. Since this will no longer occur, there is no need to worry about combustion starting even if something moves away from the operation switch due to vibration or the like.

In the control device according to the fourth aspect, when the operation switch is pressed to generate the first voltage signal, the control means starts pre-purge in the burner. Then, when the operator releases the operation switch at the end of the pre-purge or before the end of the pre-purge and a second voltage signal is generated, the control means starts combustion in the burner. Therefore, if an object falls and touches the operation switch, only pre-purging is performed and there is no danger of combustion.

[0014]

Embodiments Hereinafter, embodiments in which the present invention is applied to a gas fan heater will be described with reference to the drawings.

In FIG. 6, reference numeral 1 denotes an exterior case having an air inlet 3 with an air filter 2 attached to the upper back and a hot air outlet 4 at the lower front. 6 is a gas burner provided in the combustion chamber 5; 7 is a blower fan consisting of a cross flow fan provided below the combustion chamber 5; 8 is a cover plate that covers the top and front surface of the combustion chamber 5; 9 is provided between the combustion chamber 5 and the cover plate 8, and guides the air flowing in from the suction port 3 and the combustion gas from the combustion chamber 5 to the ventilation fan 7; 10 is the ventilation fan 7;
A fan casing that guides hot air from the air to a hot air outlet 4, 1
Reference numeral 1 denotes an automatic winding type cord reel device provided in a lower space 12 within the exterior case 1 partitioned by the fan casing 10.

Reference numerals 13 and 14 denote rectifier plates 1 which also serve as heat shield plates and are provided in the air passage 15 between the cover plate 8 and the exterior case 1.
Reference numeral 6 designates a stand that also serves as the bottom plate of the exterior case 1, 17 a control device, 18 a tact-type operating switch (operation switch) operated by pressing a push button 18A, 19 a room temperature sensor consisting of a thermistor, and 20 an igniter.

FIG. 1 shows the basic configuration of the control device 17. In FIG. 1, 21 is a microcomputer (hereinafter referred to as a microcomputer) as a control means that has a built-in A/D converter, and on the input side of the microcomputer 21 are a voltage signal generation means 22 including an operation switch 18, and a temperature setting device. Vessel 2
3 and a room temperature sensor 19 are provided. In the voltage signal generating means 22, a resistor 26 and a normally open operation switch 18 are connected in series between a DC power supply 24 and a ground 25, and an intermediate connection point 27 of these is connected to a microcomputer 21 via a resistor 28.
connected to the input side of the

On the output side of the microcomputer 21, a former solenoid valve 29 is sequentially inserted into the gas supply pipe (not shown) of the gas burner 6.
A proportional control valve 30, an igniter 20, a driving motor 7M for the blower fan 7, and an operation lamp 31 are provided. Further, the drive motor 7M is provided with a rotation speed detector 32, and its detection signal is input to the microcomputer.

As shown in FIG. 2, at time t1, when the push button 18A of the operation switch 18 is lightly pressed by hand, the operation switch 18 is turned on, and the voltage at the intermediate connection point 27 of the voltage signal generating means 22 changes from H to H. Changes to L (first change)
. At this time, the microcomputer 21 remembers that there has been a first change in the voltage signal, and lights up the operation lamp 31.

At time t2, when the push button 18A is released, the operation switch 18 is turned off, and the voltage at the intermediate connection point 27 of the voltage signal generating means 22 changes from L to H (
second change). At this time, in order to detect the second change in the voltage signal following the first change in the voltage signal, the microcomputer 21 first starts the drive motor 7M at a medium speed and operates the blower fan 7 at a medium speed. Then, the gas burner 6 is pre-purged.

At time t3, the microcomputer 21 operates the igniter 20 to start pre-ignition. In addition, a large current corresponding to strong combustion is applied to the proportional control valve 30,
The close contact between the valve body and the sealing surface of the proportional control valve 30 is released.

At time t4, when the pre-purge is completed, the microcomputer 21 sets the proportional control valve 30 to a valve opening appropriate for medium combustion, and energizes the original solenoid valve 29 to open it. Therefore, combustion is performed in the gas burner 6 with medium combustion suitable for ignition.

In this manner, when combustion starts in the gas burner 6, the microcomputer 21 compares the amount of combustion in the gas burner 6 with the set temperature set by the temperature setting device 23 and the room temperature detected by the room temperature sensor 19 at time t5. The amount of combustion is determined according to the temperature difference. In the example in Figure 2, the temperature difference is large;
The gas burner 6 is caused to perform strong combustion by operating the blower fan 7 at a strong wind speed and setting the proportional control valve 30 to a valve opening suitable for strong combustion. Thereafter, when the temperature difference between the set temperature and the room temperature becomes smaller, the amount of combustion in the gas burner 6 decreases from strong combustion to medium combustion and further to weak combustion, and the room temperature is maintained near the set temperature.

During combustion operation, indoor air is drawn into the exterior case 1 from the air suction port 3 by the blower fan 7, and a portion of the air enters the combustion chamber 5 through the intake port 5A. Then, this air is mixed with gas fuel supplied via the solenoid valve 29 and the proportional control valve 30, and burned in the gas burner 6.

After the combustion gas of the gas burner 6 is discharged from the exhaust port 5B, the air in the ventilation passage 9 cools the outer wall of the combustion chamber 5, and the operating circuits of the control device 17 and operation switch 18 etc. in the upper part of the interior of the exterior case 1 are released. The air is combined with the air that controls the temperature rise of the parts and is sucked into the blower fan 7. Then, the warm air discharged from the blower fan 7 is sent to the fan casing 10.
The hot air is guided along the hot air outlet 4 and discharged into the room.

The rotational speed control of the driving motor 7M is performed by voltage control or phase control of the driving motor 7M so that the rotational speed signal from the rotational speed detector 32 becomes a set rotational speed commensurate with the amount of combustion. .

At time t6, when the push button 18A of the operation switch 18 is pressed, the microcomputer 21 detects only the first voltage change, turns off the operation lamp 31, and stops combustion in the gas burner 6. That is, the main solenoid valve 29 and the proportional control valve 30 are closed to prevent gas fuel from being supplied to the gas burner 6. At this time, the blower fan 7 continues to operate, and stops operating at time t7 when a predetermined afterpurge time has elapsed.

If a falling object touches the operation button 18A of the operation switch 18 while the gas burner 6 is stopping combustion,
The operation switch 18 remains on. In such a case, as shown in FIG. 3, when a predetermined time T (for example, several seconds) has elapsed since the voltage signal changed from H to L due to the falling object, the microcomputer 21 performs error processing and prevents the operation from occurring. At the same time, for example, the operation lamp 31 is made to blink to notify the abnormal state. If the customer notices this, removes the fallen object, turns the power back on and resets the microcomputer 21, the machine can be operated again.

FIGS. 4 and 5 show other embodiments of the present invention. In the apparatus shown in FIGS. 4 and 5, when the voltage signal of the voltage signal generating means 22 changes from H to L, the operation lamp 32 is turned on and pre-purge is started.

[0030] From this point in time (t1), a predetermined time T
If the voltage signal changes from L to H before the elapse of 5 seconds (for example, 5 seconds), the next combustion sequence is started (see FIG. 4). However, if the voltage signal remains at L, it is assumed that there is a falling object, and the microcomputer 21 cancels the pre-purge, prevents a transition to the subsequent combustion sequence, performs error processing, and flashes the operation lamp. (See Figure 5). Of course, at the end of pre-purge (t4), it may be determined whether the voltage signal is H or L, and when it is H, the combustion sequence is continued, and when it is L, error handling may be performed.

[0031] This invention is applicable not only to operation switches, but also to
A timer switch that starts operation at a predetermined time,
The present invention can be similarly applied to an operation switch such as a timer switch that stops combustion after a predetermined period of time.

[0032]

Effects of the Invention Since the present invention is constructed as described above, in the control device for a combustion machine according to claim 1, when a falling object touches the operation switch during combustion stop, the first change in the voltage signal occurs. Even if a change occurs, unless the first change occurs subsequently,
Combustion can be prevented from starting, and safety against falling objects can be maintained while simplifying driving operations. Further, since combustion will not be started by a falling object, there is no fear that the falling object will move away from the operation switch due to vibrations accompanying combustion and combustion will occur.

Furthermore, in the control device of claim 2, combustion can be stopped quickly by simply pressing the operation switch lightly, and even if a falling object touches the operation switch during combustion, combustion can be stopped immediately. and has excellent safety.

Further, in the control device according to claim 3, when an object falls and touches the operation switch and a first change occurs in the voltage signal, an error process is performed when that state continues for a predetermined period of time; Since driving will no longer be carried out, after that,
Even if an object moves away from the operating switch due to vibration or the like, combustion can be prevented from starting, further improving safety.

Furthermore, in the control device of claim 4, the pre-purge can be started as soon as the operation switch is touched, and the next combustion sequence can be started when the operation switch is released. The combustion operation is made smooth, and if a falling object touches the operation switch, only pre-purge is performed and combustion can be prevented.

[Brief explanation of the drawing]

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

FIG. 2 is a time chart for explaining the operation of the control device.

FIG. 3 is a time chart for explaining the operation in the case of an abnormality.

FIG. 4 is a time chart for explaining the operation of another embodiment of the invention.

FIG. 5 is a time chart for explaining the operation in the case of an abnormality.

FIG. 6 is a sectional view of a gas fan heater showing an example of a combustor.

[Explanation of symbols]

6 Burner 7 Blow fan 18 Operation switch (operation switch) 21 Microcomputer (control means) 22 Voltage signal generation means 29 Original solenoid valve 30 Proportional control valve

Claims (4)

[Claims] 1. An operation switch that is turned on or off during manual operation, a voltage signal generation means that generates a different voltage signal when the operation switch is operated and not operated, and a voltage signal of the voltage signal generation means. and control means for detecting the presence or absence of manual operation and controlling combustion in the burner according to the determination result, and the control means detects the voltage signal of the voltage signal generating means during combustion stoppage of the burner. 1. A control device for a combustion machine, characterized in that the control device is configured to start combustion in a burner when a first change and a second change in a direction different from the first change are sequentially detected. 2. A claim characterized in that the control means is configured to stop combustion in the burner when detecting a first change in the voltage signal of the voltage signal generating means during combustion in the burner. 1. The control device for a combustion machine according to 1. 3. The control means performs error processing when the time from detecting the first change in the voltage signal of the voltage signal generating means to detecting the second change is longer than a predetermined time while combustion of the burner is stopped. 3. The control device for a combustion machine according to claim 1, wherein the control device performs the following operations. 4. An operation switch that is turned on or off during manual operation, and voltage signal generation means that generates a first voltage signal and a second voltage signal when the operation switch is operated and not operated, respectively. The control means detects the voltage signal of the voltage signal generating means to determine whether or not there is a manual operation, and controls combustion in the burner according to the determination result. When the first voltage signal is detected, prepurge in the burner is started, and when the second voltage signal is detected at the end of prepurge or before the end of prepurge, combustion in the burner is started. A control device for a combustion machine, characterized in that it is configured to prohibit combustion in a burner when a first voltage signal is detected.