KR950003273B1 - Control device of hot-water boiler - Google Patents

Abstract

In the control device to control an electric safty valve according to the output of a serial circuit which comprises a burner, a 1st thermocouple, a 2nd thermocouple ocouple, the 2nd thermocouple is connected with the 1st thermocouple in series within a fixed time after lighting. But the 2nd thermocouple is reverse connected when the fixed time passes.

Description

Control device of the equipment

1 is a circuit diagram showing a connection switching circuit and an ignition detection circuit in the control apparatus of this embodiment.

2 is a schematic view showing the configuration of the gas instantaneous scrubber of the present embodiment.

3 is a block diagram showing an apparatus for controlling a gas instantaneous scrubber according to an embodiment of the present invention.

4 is a time chart for explaining the operation of the control device of this embodiment.

* Explanation of symbols for main parts of the drawings

1: gas instantaneous scrubber 5: heat exchanger

10: gas pipe (fuel supply path) 11: electronic safety valve

16: burner 19: 1st thermocouple (1st thermocouple)

20: second thermocouple (second thermocouple) 30: control device

35: connection switching circuit (connection switching means)

The present invention relates to a control device having a thermocouple for controlling a fuel safety valve in a water purifier.

For example, in a gas cooker, in order to stop the supply of fuel gas to the burner when the burner has failed, the first thermocouple is provided in close proximity to the burner, and the thermocouple is not sufficiently heated by misfire or oxygen deficiency. When the output of the thermocouple is reduced, the gas safety valve is closed.

In addition, in order to close the gas safety valve even when a combustion abnormality such as clogging of the heat exchanger occurs, a second thermocouple is also provided in the heat exchanger heated by the burner, and the second thermocouple is connected to the first thermocouple. In case of normal combustion, the gas safety valve remains open because the first thermocouple output is sufficiently larger than the second thermocouple output, and the difference between the thermocouple outputs is small due to abnormal combustion. Ground level, gas safety valve closes.

In this case, when the ignition detection of the burner is combined with the first thermocouple, the output by the second thermocouple is hindered for ignition detection.

Therefore, in the invention of Japanese Patent Application Laid-Open No. 63-17312, the second thermocouple output is shorted within a predetermined time of the initial ignition, and the second thermocouple output is invalidated. The thermocouple of is connected in a reverse direction with respect to the first thermocouple.

However, in the case of re-ignition in a water purifier, especially in the case where the first and second thermocouples are extinguished immediately after being fully heated, the thermocouple after re-ignition with respect to the electromotive force of the thermocouple before re-ignition. The change in the electromotive force of is small, and this small change in the electromotive force cannot be discriminated by the ignition detection.

As a result, many gas stoves force the gas safety valve to be closed until the electromotive force of the thermocouple is sufficiently lowered even after the reignition operation is performed. Since pressing does not ignite for a predetermined time, the user is burned.

According to the present invention, when an abnormality such as burner burnout and clogging of the heat exchanger occurs, combustion is always stopped to prevent gas leakage, and ignition detection can be performed even in re-ignition operation even after re-ignition immediately after extinguishing. It is for the purpose of having.

According to the present invention, a burner and a first thermocouple and a second thermocouple each provided in a heat exchanger heated by the burner are connected in series to form a series circuit, and the fuel supply path to the burner is output in accordance with the output of the series circuit. A control device for a water purifier for controlling an electronic safety valve arranged, wherein the second thermocouple is connected in series with the first thermocouple in a forward direction within a predetermined time after the start of the ignition operation of the burner, and after the ignition operation starts. After a predetermined time has elapsed, it is a technical means to provide connection switching means for connecting the second thermocouple in series with the first thermocouple in the reverse direction.

In the present invention, since the thermocouples are connected in series so that a predetermined time has elapsed since the start of the ignition operation, the output of the series circuit is represented by the sum of the electromotive force of each thermocouple.

In this case, since the ignition detection is performed based on the sum of the electromotive force change amounts of each thermocouple, the change amount can be increased.

Therefore, compared with the case where the first thermocouple electromotive force is detected alone, the ignition detection can be identified without waiting for the re-ignition operation until the electromotive force of the thermocouple after digestion sufficiently drops.

After the predetermined time has elapsed, since the second thermocouple is connected in a reverse direction with respect to the first thermocouple, the electronic safety valve is kept open when normal combustion is being performed.

The electronic safety valve closes when it is misfired during combustion or when normal combustion is not possible due to blockage of the heat exchanger.

In the present invention, two thermocouples are connected in the forward direction within a predetermined time after the start of the ignition operation, and the ignition detection is performed based on the output thereof. Even if the operation is not prohibited, the ignition detection can be identified and ignited quickly after extinguishing.

Next, the present invention will be described based on Examples.

2 shows the gas instantaneous water purifier 1, and the water supplied from the water supply pipe 2 passes through the water stopper 3 and the water governor 4 and is provided with a plurality of fins. It is led to and flows out from the tapping pipe 6 to the shower head 7 at its tip.

The water stopper 3 is an index valve by manual operation, is opened by the first push operation, is opened by a lock mechanism (not shown), and is locked by the second push operation. Is released and returns to the closed state.

The water governor 4 is also a driving unit of the hydraulically actuated gas valve 12 installed in the gas passage described later while controlling the inflow of water to a constant flow rate, and the water flowing in when the water stopper 3 is opened. When the diaphragm is displaced by means of the connecting member, the gas valve 12 is opened.

On the other hand, the fuel gas is guided by the gas pipe 10 and passes through the gas safety valve 11 as the gas safety valve, and passes through the gas valve 12 driven by the water governor 4, the gas governor ( It is supplied to each air supply port of the burner 16 which adjusted to a certain quantity in 13), and ejects from the fuel injection pipe | tube 15 provided with the some nozzle 14, and arranged the sheet metal burner in a line.

The gas pipe 10 branches downstream of the electromagnetic safety valve 11 to become the ignition gas passage 10a, and an ignition burner 17 is provided at the tip of the ignition gas passage 10a.

In the vicinity of the ignition burner 17, an ignition electrode 18 arranged to face a ground electrode (not shown) and a first thermocouple 19 heated by the ignition burner 17 are provided.

In addition, the body portion 5a of the heat exchanger 5 is provided with a second thermocouple 20 for detecting the occurrence of clogging or the like of the heat exchanger 5.

In addition, the water supply pipe 2 is provided with a flow regulating valve (not shown) so that the hot water supply temperature can be adjusted by adjusting the flow rate.

The gas instantaneous water purifier 1 of the above structure is controlled by the control apparatus 30 shown in FIG.

The control device 30 has a switch 30A for generating a signal for ignition operation in conjunction with opening the water stopper 3, and the control device 30 is operated by using a battery (not shown) as a power source. The connection state of the trial timer circuit 31, the forced operation timer circuit 32, the pulse oscillation circuit 33, the sparker circuit 34, and each of the thermocouples 19 and 20, which is composed mainly of the operational amplifier and the transistor, Detection part switching circuit 38 and timer 39 for switching the connection switching circuit 35, the ignition detection circuit 36, the combustion detection circuit 37, the ignition detection circuit 36 and the combustion detection circuit 37 to be switched. The suction coil energization circuit 40 and the retaining coil energization circuit 41 are provided.

The function of each circuit will be described below.

The trial timer circuit 31 is a timer that clocks the time T1 (for example, 3.6 seconds) for performing the ignition operation by the open signal of the switch 30A.

During the operation of the trial timer circuit 31, the sparker circuit 34 operates to generate a high voltage, and spark discharge is performed on the ignition electrode 18. FIG.

The forced operation timer circuit 32 is a timer that operates only for the first 0.7 seconds when the switch 30A is closed.

The pulse oscillation circuit 33 is a circuit which alternately outputs the high level for 0.7 seconds and the low level for 0.5 seconds, and here the output state of the high level is determined by the output of the forced operation timer circuit 32, and the switch 30A If the forced timer circuit 32 is operated when is closed, then it continues to operate while the trial timer circuit 31 is operating.

The connection switching circuit 35 is a circuit for switching the connection state between the first thermocouple 19 and the second thermocouple 20.

Here, as shown in FIG. 1, the positive electrode 19a of the first thermocouple 19 is connected to the movable contact 42a of the relay 42, and the negative electrode 19b is grounded.

On the other hand, the positive electrode 20a of the second thermocouple 20 is connected to the upper closed contact 42c of the relay 42 and the upper contact 43b of the relay 43, and the negative electrode 20b is opened to the upper side of the relay 42. It is connected to the contact 42b and the normally closed contact 43c of the relay 43. As shown in FIG.

Each of the relays 42 and 43 starts operation in accordance with the closing operation of the switch 30A, and only the predetermined time T2 (for example, 5 seconds) during which the timer 39 is operating is driven, and each movable contact ( 42a and 43a are connected to each of the upper contacts 42b and 43b, and when the operation of the timer 39 ends, the movable contacts 42a and 43a are respectively the upper contacts 42c and 43c. ) Is connected.

In addition, while the timer 39 is in operation, the relay 44 of the detection part switching circuit 38 is driven, the movable contact 44a is connected to the upper contact 44b, and the operation of the timer 39 ends. The lower surface movable contact 44a is connected to the upper contact 44c.

As a result, each of the thermocouples 19 and 20 forms a serial circuit connected in series in the forward direction while the timer 39 is in operation, and is connected to the ignition detecting circuit 36, so that the operation of the timer 39 is stopped. The two thermocouples 20 are connected in series with the first thermocouple 19 in the reverse direction and connected to the combustion detection circuit 37.

The ignition detection circuit 36 determines the ignition state of the burner 16 based on the output of the series circuits of the first and second thermocouples 19 and 20 connected in series in the forward direction by the connection switching circuit 35. As shown in FIG. 1, the amplification circuit 45 for amplifying the output of the series circuit, the memory circuit 46 for storing the initial output at the time of ignition operation, the initial output and the subsequent outputs are compared with each other. The determination circuit 47 determines the case where the difference is larger than the predetermined value as the ignition detection state.

The combustion detection circuit 37 burns or heat exchanges the burner 16 based on the output of the series circuits of the first thermocouple 19 and the second thermocouple 20 connected in series in the reverse direction by the connection switching circuit 35. A circuit for detecting the blockage of the pins of the instrument 5 includes an amplifying circuit 48 for amplifying the output of the series circuit, and a determining circuit 49 for discriminating when the output is lower than the reference level as abnormal combustion.

The suction coil energizing circuit 40 and the holding coil energizing circuit 41 are both circuits provided for driving the valve element of the electromagnetic safety valve 11.

Here, the electromagnetic safety valve 11 is provided with two coils of a suction coil 11a having a small resistance value and a large driving force of the valve body and a holding coil 11b having a large resistance value and a small suction force in order to drive the valve body. Each coil 11a, 11b is energized by each electricity supply circuit 40, 41, respectively.

The adsorption coil energizing circuit 40 generates a large magnetic force on the adsorption coil 11a by a large current and attracts the valve body. The suction output of the forced operation timer circuit 32 and the high level of the pulse oscillation circuit 33 are generated. The adsorption coil 11a is energized only for 0.3 second by the output of.

The holding coil energizing circuit 41 energizes the holding coil 11b according to the high level output of the pulse oscillation circuit 33 and the output signal of the ignition detecting circuit 36 or the combustion detecting circuit 37.

In addition, here, in order to reduce the electric power for driving the valve element of the electromagnetic safety valve 11, in the adsorption coil energizing circuit 40, the output of the forced operation timer circuit 32 or the high level of the pulse oscillation circuit 33 is used. When the output is continued for 0.7 seconds each, a large current flows intensively only for the first 0.3 seconds of energization to the suction coil 11a to drive the valve body of the solenoid safety valve 11, and the remaining 0.4 seconds is energized to the holding coil 11b. By this, the open state of the electromagnetic safety valve 11 is maintained for 0.7 seconds.

The operation of the gas instantaneous scrubber 1 of the present embodiment having the above configuration will be described with reference to FIG.

When the user opens the water stopper 3, the switch 30A closes in conjunction with the water stopper 3, so that the trial timer circuit 31 and the forced operation timer 32 start to operate, and the electronic safety valve 11 With the opening, spark discharge is performed at the ignition electrode 18.

At this time, by the start of operation of the timer 39, the thermocouples 19 and 20 which have been connected in the reverse direction up to that time are connected to the ignition detection circuit 36 switched in the forward direction.

On the other hand, since the gas valve 12 is opened by the water governor 4 with the inflow of water, fuel gas is supplied to the ignition burner 17 and the burner 16, and the ignition electrode 18 which has already been operated. Ignition by flame discharge.

Thereafter, the flame discharge continues at the ignition electrode 18 while the trial timer circuit 31 is in operation, and the flame discharge is stopped when the trial timer circuit 31 is finished.

At this time, since the thermocouples 19 and 20 are connected in series in the forward direction, the electromotive force of each of the thermocouples 19 and 20 is added, and when the sum of the electromotive force change amounts is larger than a predetermined value, ignition detection is performed.

Therefore, ignition detection is performed by the ignition detection circuit 36, the ignition detection signal is connected to the holding coil energizing circuit 41, and the electromagnetic safety valve 11 is kept open.

After a predetermined time (5 seconds) has elapsed since the start of use, the connection of the thermocouples 19 and 20 is switched in the reverse direction by the connection switching circuit 35, and the detection detection circuit 38 detects the combustion. The circuit 37 is connected.

Then, the combustion state is detected by the electromotive force of each of the thermocouples 19 and 20 connected in series in the reverse direction, and when the misfire occurs, the electromotive force of the first thermocouple 19 is lowered or the heat of the heat exchanger 5 is reduced. If a blockage or the like occurs, the difference in the electromotive force of the thermocouples 19 and 20 becomes small, and the voltage of the series circuit becomes smaller than the reference level voltage, so that the energization to the electromagnetic safety valve 11 is stopped and closed. It is safe because its supply is stopped.

In addition, during operation of the trial timer circuit 31, as shown by the broken line until the ignition is detected, the suction coil 11a and the holding coil 11b are energized for 0.7 seconds repeatedly for 0.5 seconds, and accordingly, the electronic safety valve ( 11) is opened. Therefore, even if the electronic safety valve 11 is not ignited when first opened, there is a possibility that the second or third ignition may occur afterwards, so that the user does not need to repeatedly perform the ignition operation.

In addition, since the electronic safety valve 11 is closed by 0.5 second, the fuel gas which flowed out from the burner 16 will spread | diffuse for that time, and even if it ignites after that, the ignition voltage can be made small, and it can perform safe ignition.

As described above, in the present invention, since the connection state of the thermocouple is in the forward direction until a predetermined time after the start of ignition has elapsed, the ignition detection can be performed by the sum of the electromotive force change amounts of the thermocouple.

In addition, after a predetermined time has elapsed, since the thermocouple is connected in the reverse direction as in the prior art, safety can be ensured in case of a combustion abnormality.

In the above embodiment, the connection switching of the thermocouple is performed using two relays, but a timer switch of the contact point of the circuit may be used.

Claims (1)

An electronic safety valve disposed in a fuel supply path to the burner in accordance with the output of the series circuit by connecting the burner and the first thermocouple and the second thermocouple provided in the heat exchanger heated by the burner in series. A control apparatus for a water purifier for controlling a gas heater, wherein the second thermocouple is connected in series with the first thermocouple in a forward direction within a predetermined time after the start of the ignition operation of the burner, and after the predetermined time after the start of the ignition operation has elapsed. And a connection switching means for connecting the second thermocouple in series with the first thermocouple in a reverse direction.

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