JPH08254312A - Combustion condition detector for combustion instrument - Google Patents

Abstract

PURPOSE: To provide a combustion condition detector for combustion instrument capable of deecting faulty spread of fire, ignition failure and the like well. CONSTITUTION: A driving current detecting means 43 detects the driving current of a fan motor 29, which is installed in the supplying flow passage of combustion air to drive fan, while an abnormal combustion judging means 44 judges the abnormality of combustion condition, such as faulty spread of fire, ignition miss and the like, on the basis of the driving current detected by the driving current detecting means 43.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion state detecting device for detecting a fire transfer abnormality in a combustion device or a malfunction of a capacity switching solenoid valve.

[0002]

2. Description of the Related Art Conventionally, 1 or 2 is provided in a fuel gas supply passage.
In a combustion device that is equipped with the above capacity switching solenoid valve and that can switch the combustion capacity by opening and closing this capacity switching solenoid valve, a spark plug as an ignition device and a frame rod as a combustion monitoring device, One was provided for each.

Further, when the combustion capacity is switched from small to large, the gas pressure of the fuel gas is maintained at the transfer pressure for a certain period of time, and the capacity switching solenoid valve is opened during this period to complete the transfer of fire. I was thinking

[0004]

However, in the above-mentioned conventional configuration, there is a possibility that a failure or a fire transfer failure of the capacity switching solenoid valve cannot be detected, and unburned fuel gas is discharged.

The present invention has been proposed in view of the above points, and it is an object thereof to provide a combustion state detecting device for a combustion device, which can favorably detect a fire transfer defect, an ignition defect or the like.

[0006]

In order to solve the above problems, the present invention takes the following technical means.

That is, according to the invention described in claim 1 of the present application, a combustion gas is provided with a solenoid valve in a fuel gas supply passage and combustion is performed by opening and closing the solenoid valve. Drive current detection means for detecting a drive current of a fan motor for driving a fan installed in the fan, and abnormal combustion determination means for determining an abnormal combustion state based on the drive current detected by the drive current detection means. It is characterized by that.

The invention described in claim 2 of the present application is
In a combustion device in which one or more capacity switching electromagnetic valves are provided in the fuel gas supply channel, and the combustion capacity can be switched by opening / closing the capacity switching electromagnetic valve, the combustion air supply channel is provided. Based on the drive current detected by the drive current detection unit that detects the drive current of the fan motor that drives the installed fan, and the drive current detection unit,
An abnormal combustion determination means for determining an abnormality in the capacity switching solenoid valve or the fire transfer and shutting off the fuel gas supply flow channel when the abnormality occurs is provided.

The invention described in claim 3 of the present application is
In a combustion device in which one or more capacity switching solenoid valves are provided in the fuel gas supply passage and the combustion capacity can be switched by opening and closing the capacity switching solenoid valve, the capacity switching solenoid valve during combustion And a drive current detection means for detecting a drive current of a fan motor for driving a fan installed in the supply path of the combustion air after completion of the time measurement by the time measurement means. The present invention is characterized in that abnormal combustion determination means for determining an abnormality in the fire transfer based on the drive current detected by the current detection means and performing the fire transfer again when the abnormality occurs is provided.

[0010]

According to the invention described in claim 1, the drive current detection means detects the drive current of the fan motor for driving the fan installed in the combustion air supply passage, and the abnormal combustion determination means is provided. On the basis of the drive current detected by the drive current detection means, it is determined whether the combustion state is abnormal, such as a fire transfer failure or an ignition failure.

According to the second aspect of the present invention, the drive current detection means detects the drive current of the fan motor for driving the fan installed in the combustion air supply passage, and the abnormal combustion determination means is provided. Based on the drive current detected by the drive current detection means, it is determined whether or not there is an abnormality in the capacity switching solenoid valve or the fire transfer, and the fuel gas supply flow path is shut off when the abnormality occurs.

According to the invention described in claim 3, the time measuring means measures a predetermined time from the opening of the capacity switching electromagnetic valve during combustion, and the drive current detecting means, after the time measurement by the time measuring means is completed, The drive current of the fan motor that drives the fan installed in the combustion air supply flow path is detected, and the abnormal combustion determination means determines an abnormal fire transfer based on the drive current detected by the drive current detection means. However, if there is an abnormality, the fire should be transferred again.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The preferred embodiments of the present invention will be described below.
A specific description will be given with reference to the drawings.

FIG. 2 is an overall configuration diagram of a hot water supply apparatus with a bath kettle equipped with a combustion state detecting device for a combustion apparatus according to the present invention. Fuel gas passes through a gas pipe 1 and a hot water supply gas pipe 2. Is supplied to the hot water supply burner 3 and further to the bath burner 5 through the bath gas pipe 4 branched from the gas pipe 1. The gas pipe 1 is provided with an original solenoid valve 6 for opening and closing a fuel gas passage constituted by the gas pipe 1 in the vicinity of a branch point between the hot water supply gas pipe 2 and the bath gas pipe 4. In the hot water supply gas pipe 2, a hot water supply solenoid valve 7 for opening and closing a flow path of the fuel gas to the hot water supply burner 3 and a fuel gas to the hot water supply burner 3 are provided in the vicinity of a branch point with the gas pipe 1. A proportional valve 8 for adjusting the flow rate is interposed. Solenoid valve for hot water supply 7
Are located upstream of the proportional valve 8. In the bath gas pipe 4, a bath electromagnetic valve 9 that opens and closes a flow path of the fuel gas to the bath burner 5 is provided in the vicinity of a branch point with the gas pipe 1. Two hot water supply capacity switching solenoid valves 10a, 10b for switching the combustion capacity of the hot water supply burner 3 are provided at the end of the hot water supply gas pipe 2 on the hot water supply burner 3 side. A bath capacity switching solenoid valve 11 for switching the combustion capacity of the bath burner 5 is provided at the end of the pipe 4 on the bath burner 5 side. Solenoid valve for capacity switching 10
The numbers a and 10b of the hot water supply burners 3 corresponding to each other are different from each other, and the hot water supply capacity can be switched to a plurality of stages by the combination of the open states of the capacity switching electromagnetic valves 10a and 10b. At the flame forming position of the hot water supply burner 3, a hot water supply spark plug 12 that ignites the hot water supply burner 3
And a hot-water supply frame rod 13 for detecting the flame of the hot-water supply burner 3, and at the flame formation position of the bath burner 5, a bath spark plug 14 for igniting the bath burner 5 and a bath burner A flame frame rod 15 for detecting the flame of the burner 5 is installed.

Water is supplied to the hot water supply heat exchanger 18 through the water supply pipe 17, and the hot water heated by the hot water supply heat exchanger 18 is supplied to the hot water tap 20 through the hot water supply pipe 19, or It is supplied to the bathtub 24 through a drop pipe 21 and a bath outflow pipe 22 or a bath return pipe 23 branched from the hot water supply pipe 19. A water supply water amount sensor 25 for detecting the amount of water passing through the water supply pipe 17 is interposed in the water supply pipe 17. The bath return pipe 22 and the bath return pipe 23 are in communication with each other via a bath heat exchanger 26, and the bath return pipe 23 is connected to the circulation pump 2
7 and the water flow switch 28 are interposed. At the time of reheating the bath, the hot water in the bathtub 24 is supplied to the bath heat exchanger 26 through the bath return pipe 23 by the circulation pump 27,
It is heated by the bath heat exchanger 26 and returned to the bathtub 24 through the bath outlet pipe 22. At this time, the water flow switch 28
Thus, it is detected that water is flowing through the bath return pipe 23.

The original solenoid valve 6, hot water supply solenoid valve 7, proportional valve 8, bath solenoid valve 9 and hot water supply capacity switching solenoid valve 10
The a, 10b, the bath capacity switching solenoid valve 11, etc. are based on various sensors such as the hot water supply water amount sensor 25 and the water flow switch 28, and the operation of a remote controller (not shown) by the user. 2 is not shown). Further, the hot water supply burner 3 is supplied with combustion air by a hot water supply fan driven by a hot water supply fan motor 29. Further, combustion air is supplied to the bath burner 5 by a hot water supply fan driven by a bath fan motor 30. Further, the flow rate of the fuel gas flowing through the bath gas pipe 4 is changed by the gas governor 31 which is adjusted to a constant gas pressure.

As shown schematically in FIG. 3, the hot water supply burner 3 is divided into two blocks 3a and 3b. The block 3a is opened and closed in a fuel gas supply passage by a capacity switching electromagnetic valve 10a. The block 3b is a solenoid valve 10 for capacity switching.
The fuel gas supply passage is opened and closed by b. That is,
When the capacity switching solenoid valve 10a is opened and the capacity switching solenoid valve 10b is closed, the hot water supply capacity is small, and both the capacity switching solenoid valve 10a and the capacity switching solenoid valve 10b are opened. The state in which the hot water is supplied is large. The capacity switching solenoid valve 10a is closed to close the capacity switching solenoid valve 10a.
Although there may be a state in which the hot water supply capability is in the state where the valve b is opened, in the present embodiment, the hot water supply capability is assumed to be a two-stage switch between large and small in order to make the explanation easy to understand.

FIG. 1 is a circuit block diagram of a combustion state detecting device for a combustion device according to the present invention.
The AC power from the 0 V commercial power supply is converted into DC power by the power supply means 41, and is supplied as drive power to the fan motor 29 via the drive means 42. The drive current detection means 43 detects the drive current supplied to the fan motor 29. Abnormal combustion determination means 44 determines the combustion state abnormality based on the detection signals from the drive current detection means 43 and the hot water supply frame rod 13. Timing means 45
Measures the time from the opening of the capacity switching solenoid valve 10b at the time of fire transfer. The abnormal combustion determination means 44 and the timing means 45 are realized by a microcomputer 46 that controls the entire hot water supply device with a bath kettle. In addition,
The memory 47 stores the relationship between the drive current of the fan motor 29 and the combustion state, and the register 48 is used when the data read from the memory 47 is temporarily stored.

Next, the operation will be described. First, a normal combustion state detection routine will be described with reference to the flowchart shown in FIG. First, the abnormal combustion determination means 44
, It is determined whether or not the full-stage combustion state is set (step S
1). Specifically, it is determined whether or not a signal for opening the capacity switching solenoid valves 10a and 10b is output from the microcomputer 46. If it is the full-stage combustion state, the abnormal combustion determination means 44 reads the current range of the appropriate drive current of the fan motor 29 in the full-stage combustion state from the memory 47 and stores it in the register 48 (step S2).

That is, if the rotation speed of the fan motor 29 is constant, there is a relationship between the combustion state of the hot water supply burner 3 and the drive current of the fan motor 29 as shown by the solid line in FIG. The combustion abnormality can be determined by detecting the drive current of the motor 29. Specifically, the capacity switching solenoid valves 10a and 10b are opened to cause the hot water supply burner 3 to operate.
When all the blocks 3a and 3b of are in the combustion state,
The drive current of the fan motor 29 is about I1. Also,
Although the capacity switching solenoid valves 10a and 10b are open, only the block 3a of the hot water supply burner 3 is in the combustion state,
When the unburned fuel gas is flowing out to the block 3b without burning, the drive current of the fan motor 29 is about I2. Further, the capacity switching solenoid valve 10
When a is opened, the capacity switching electromagnetic valve 10b is closed, and only the block 3a of the hot water supply burner 3 is burning, the drive current of the fan motor 29 is about I3. Further, when both the capacity switching electromagnetic valves 10a and 10b are closed and the hot water supply burner 3 is not burning at all, the drive current of the fan motor 29 is about I4.

Next, the abnormal combustion judging means 44 judges whether or not the flame of the block 3a of the hot water supply burner 3 is detected (step S3). Specifically, the detection signal from the hot water supply frame rod 13 is sent to the microcomputer 46.
It is determined whether or not it is input to. If the flame is detected, the abnormal combustion determination means 44 determines whether the drive current of the fan motor 29 is appropriate (step S4). Specifically, it is determined whether the drive current of the fan motor 29 detected by the drive current detection means 43 is within the current value range stored in the register 48 in step S2. If it is not within the predetermined current value range, the abnormal combustion determination means 44 closes all of the original solenoid valve 6, the hot water supply solenoid valve 7 and the capacity switching solenoid valves 10a and 10b to burn the hot water supply burner 3. Abnormal processing for safety such as stopping and displaying the fact on a display unit such as a controller is performed (step S5), and the routine ends. As a cause of the abnormality, it is considered that the block 3b of the hot water supply burner 3 is unburned due to a poor heat transfer despite the opening of the capacity switching solenoid valve 10b. In this case, the drive current detection is performed. The drive current of the fan motor 29 detected by the means 43 is about I2. It is also possible that the solenoid valve for capacity switching 10b is not opened due to a failure. In this case, the drive current of the fan motor 29 detected by the drive current detection means 43 is about I3.

If the abnormal combustion determination means 44 determines in step S4 that the drive current of the fan motor 29 is appropriate, the combustion is normal and the routine is ended without doing anything.

In step S3, if the abnormal combustion determination means 44 determines that the flame of the block 3a of the hot water supply burner 3 is not detected, it means that the ignition error or the disappearance of the flame is reached. I do.

If the abnormal combustion determination means 44 determines in step S1 that the combustion is not full-stage combustion, the abnormal combustion determination means 44 determines whether the combustion is one-stage combustion (step S6). Specifically, whether or not a signal for opening the capacity switching electromagnetic valve 10a is output from the microcomputer 46 and a signal for opening the capacity switching electromagnetic valve 10b is not output from the microcomputer 46. To judge. If it is a single-stage combustion, proceed to step S2,
A predetermined current range sandwiching the current value I3 is read from the memory 47 and stored in the register 48, and thereafter, the operation of step S3 and thereafter is executed.

If the abnormal combustion determination means 44 determines in step S6 that the combustion is not one-stage combustion, the abnormal combustion determination means 44 reads out a predetermined current range sandwiching the current value I4 in the non-combustion state from the memory 47 and registers 48. (Step S7), the block 3a of the burner 3 for hot water supply
It is determined whether or not the flame has been detected (step S
8). Specifically, it is determined whether or not the detection signal from the hot water supply frame rod 13 is input to the microcomputer 46. If the flame is detected, it means that the capacity switching solenoid valve 10a is out of order. Therefore, the process proceeds to step S5, and an abnormal process such as closing the original solenoid valve 6 is performed.

If no flame is detected, the abnormal combustion determination means 44 determines whether the drive current of the fan motor 29 is proper (step S4). Specifically, it is determined whether or not the drive current of the fan motor 29 detected by the drive current detection means 43 is within the current value range stored in the register 48 in step S7. If it is not within the predetermined current value range, the abnormality processing for safety such as closing the original solenoid valve 6 is performed (step S10),
Exit the routine.

Since the relationship between the drive current I of the fan motor 29 and the combustion state shown in FIG. 5 is established when the rotation speed of the fan motor 29 is constant, the above routine executes the rotation speed of the fan motor 29. It is executed in a situation where is constant.
Alternatively, a rotation speed detection unit that detects the rotation speed of the fan motor 29 may be provided and the rotation speed of the fan motor 29 may be monitored.

Further, when the combustion air supply passage in which the fan is installed partially closes and the passage resistance becomes large, the relationship between the drive current I of the fan motor 29 and the combustion state is shown in FIG. Since it changes as shown by the phantom line, when the flow path resistance changes and an erroneous detection of the combustion state occurs, the current value I1
It suffices to change the settings of I4.

In this way, the drive current of the fan motor 29 is detected, and the abnormality in the combustion state of the hot water supply burner 3 is judged from the detected value. Therefore, each block 3 of the hot water supply burner 3 is determined.
Even if the hot water supply frame rod 13 is not provided for each of a and 3b, the abnormality of the combustion state can be properly determined.

Next, the block 3a to the block 3b of the hot water supply burner 3 for switching the hot water supply capacity from small to large.
A detection flow of a fire transfer error at the time of a fire transfer to will be described with reference to the flowchart of FIG. First, the microcomputer 46 sets n to 1 (step S21) and controls the opening degree of the proportional valve 8 and the rotation speed of the fan motor 29 to predetermined values suitable for fire transfer (step S22). That is, the concentration of the fuel gas is made slightly higher and the rotation speed of the fan is made slightly lower to facilitate the transfer of fire. Next, the microcomputer 46 opens the capacity switching electromagnetic valve 10b (step S23). Next, the time counting means 45 determines whether n is 1 (step S2
4) If n is 1, time counting is started after the signal for opening the capacity switching electromagnetic valve 10b is output from the microcomputer 46 (step S2).
5). Next, the abnormal combustion determination means 44 determines whether or not the time measured by the time measuring means 45 has passed a predetermined time (step S26). If the predetermined time has passed, the time counting means 4
5 finishes the timing operation (step S27), the abnormal combustion determination means 44 reads a predetermined current range sandwiching the current value I1 from the memory 47, stores it in the register 48, and the fan detected by the drive current detection means 43. It is determined whether the drive current of the motor 29 is within the predetermined current range (step S28). If it is within the predetermined current range, the ignition transfer has been completed, and this routine is ended.

In step S28, if the drive current of the fan motor 29 detected by the drive current detecting means 43 is not within the predetermined current range, the ignition transfer has not been completed, and the process returns to step S21.

In step S26, if the time measured by the time measuring means 45 has not passed the predetermined time, 1 is added to n in order to complete the fire transfer irrespective of the completion of the fire transfer. (Step S29), Step S2
Return to 2.

As described above, after the elapse of a predetermined time from the opening of the capacity switching solenoid valve 10b, the completion of the ignition transfer is detected from the current value of the fan motor 29, so that a sensor for confirming the ignition transfer is not provided. It can realize a reliable fire transfer. Further, it is not necessary to unnecessarily set a long flame transfer time in order to secure the flame transfer, and the hot water discharge characteristic is not deteriorated.

When the fire is transferred, the rotation speed of the fan motor 29 is controlled to be constant, so that the fan motor 2 shown in FIG.
The relationship between the drive current I of 9 and the combustion state does not change.

In the above embodiment, particularly in FIG. 6, the fire transfer detection at the time of capacity switching is performed based on the drive current detected by the drive current detecting means 43 for detecting the drive current of the fan motor 29. However, it is also possible to detect the ignition at the time of ignition by the drive current detecting means 43.

Specifically, the microcomputer 46 controls the opening degree of the proportional valve 8 and the rotation speed of the fan motor 29 to a predetermined value suitable for ignition, and the detection value of the drive current detecting means 43 at this time is as shown in FIG. Confirm that it is about I4 as shown in. Then, after that, only the capacity switching electromagnetic valve 10a is opened, and the timing of the timing means 45 is started. It is confirmed that the detection value of the drive current detecting means 43 has reached about I3 shown in FIG. 5 when the time measuring means 45 measures a predetermined time. If the current value is about I3, it means that the ignition is surely performed, and if the current value is about I4, it means that the ignition is not performed.
Ignition can be detected. And in this case,
The hot water supply frame rod 13 for detecting ignition can be omitted. In addition, the configuration for performing the ignition detection by the drive current detecting means 43 in this way is provided with the capability switching electromagnetic valves 10a, 10b in addition to the type having the capability switching electromagnetic valves 10a, 10b as in the above embodiment. Needless to say, it can be applied to a hot water supply device that is not used.

Further, in the above embodiment, the hot water supply burner 3 is divided into two blocks 3a and 3b, and the hot water supply device with a bath kettle provided with two capacity switching solenoid valves 10a and 10b is used in the combustion state of the present invention. Although the example in which the detection device is provided has been described, the number of blocks of the hot water supply burner 3 is not limited to two. For example, as shown in FIG. 7, the hot water supply burner 3 is divided into three blocks 3a, 3b, 3c. The combustion state detecting device of the present invention can also be adopted in a hot water supply device configured to switch the combustion performance by the three capacity switching solenoid valves 10a, 10b, 10c. The present invention can also be applied to the bath burner 5 shown in FIG. Further, the present invention can be applied to any combustion equipment other than the water heater.

[0038]

As described above, according to the first aspect of the invention, in the combustion equipment which is provided with the electromagnetic valve in the fuel gas supply passage and which is opened and closed to perform combustion,
Drive current detection means for detecting a drive current of a fan motor for driving a fan installed in the supply path of the combustion air,
On the basis of the drive current detected by the drive current detection means, for example, an abnormal combustion determination means for determining an abnormality in the combustion state such as a fire transfer failure or an ignition failure is provided, so a sensor for determining the combustion state is provided. Even if it is not provided for each block of the burner, the combustion state can be satisfactorily determined from the drive current of the fan motor.

According to the second aspect of the present invention, one or two or more capacity switching solenoid valves are provided in the fuel gas supply passage, and the combustion capacity can be switched by opening / closing the capacity switching solenoid valve. In a possible combustion device, the drive current detection means for detecting the drive current of the fan motor for driving the fan installed in the supply path of the combustion air, and the drive current detected by the drive current detection means An abnormal combustion determination means for determining an abnormality of the switching solenoid valve or the fire transfer, and shutting off the fuel gas supply passage at the time of abnormality,
Since it is provided, even if a sensor for determining the combustion state is not provided for each block of the burner, it is possible to properly judge the abnormality of the capacity switching solenoid valve or the fire transfer from the drive current of the fan motor, and The fuel gas supply flow path can be blocked. Therefore, it is possible to favorably prevent the unburned fuel gas from flowing out.

Further, according to the invention of claim 3, one or more capacity switching electromagnetic valves are provided in the fuel gas supply passage, and the combustion capacity can be switched by opening and closing the capacity switching electromagnetic valve. In a possible combustion device, a timer that measures a predetermined time from the opening of the capacity switching solenoid valve during combustion, and a fan that drives a fan installed in the combustion air supply passage after the timer completes Drive current detection means for detecting the drive current of the motor, based on the drive current detected by the drive current detection means, to determine the abnormality of the fire transfer, abnormal combustion determination means to perform the fire transfer again when the abnormality, Since it is provided, even if there is no sensor for judging the fire transfer for each block of the burner, it is possible to properly judge the fire transfer abnormality from the drive current of the fan motor, and when there is an error, the fire transfer is restarted. It can be carried out. Further, it is not necessary to unnecessarily set a long fire transfer time in order to ensure the fire transfer, and the hot water discharge characteristics and the like are not deteriorated.

[Brief description of drawings]

FIG. 1 is a circuit block diagram of a combustion state detection device for a combustion device according to the present invention.

FIG. 2 is an overall configuration diagram of a hot water supply device with a bath kettle including a combustion state detection device according to the present invention.

FIG. 3 is a schematic view of a hot water supply burner.

FIG. 4 is a flowchart illustrating the operation of the combustion state detection device for a combustion device according to the present invention.

FIG. 5 is an explanatory diagram of a relationship between a drive current of a fan motor and a combustion state.

FIG. 6 is a flowchart for explaining the operation of the combustion state detection device for a combustion device according to the present invention during a fire transfer.

FIG. 7 is a schematic view of another example of a hot water supply burner.

[Explanation of symbols]

 10a, 10b Capacity switching solenoid valve 29 Fan motor 43 Drive current detection means 44 Abnormal combustion determination means 45 Timekeeping means

Claims (3)

[Claims] 1. In a combustion device that includes a solenoid valve in a fuel gas supply passage and performs combustion by opening and closing the solenoid valve, a fan motor for driving a fan installed in the combustion air supply passage. Combustion of combustion equipment, characterized in that: drive current detection means for detecting drive current; and abnormal combustion determination means for determining abnormality of combustion state based on the drive current detected by the drive current detection means, State detection device. 2. A combustion device comprising one or more capacity switching solenoid valves provided in a fuel gas supply passage, the combustion capacity of which can be switched by opening and closing the capacity switching solenoid valve. Drive current detecting means for detecting a drive current of a fan motor for driving a fan installed in the supply flow path of, and the capacity switching solenoid valve or the fire transfer based on the drive current detected by the drive current detecting means. An abnormal combustion determination means for determining an abnormality of the fuel gas and shutting off the supply passage of the fuel gas when the abnormality occurs, and a combustion state detecting device for a combustion device. 3. A combustion device in which one or more capacity switching electromagnetic valves are provided in a fuel gas supply passage, and the combustion capacity can be switched by opening and closing the capacity switching electromagnetic valve. After the completion of the time counting by the time counting means, the driving means detects the drive current of the fan motor that drives the fan installed in the combustion air supply flow path. Drive current detection means, and an abnormal combustion determination means for determining a fire transfer abnormality based on the drive current detected by the drive current detection means, and performing the fire transfer again in the event of an abnormality, Combustion state detection device for combustion equipment.