KR940004181B1 - Combustion control method of hot water supplying device - Google Patents

Abstract

A selection and a setting of the kind of fuel gas and a reference temp. are stored in a CPU. The CPU controls preferentially a set temp. than the reference temp. after a set temp. is inputted and control a hot water feeder. A water rate proportionally regulating valve is set to a desired degree of opening of a set temp. When a previous hit water feeder is used irrespective of ON or OFF of a sub-controller. A geared motor for use in varying a degree of opening of the water rate proportionally regulating valve adjusts a degree of opening after inputting a set temp. resulting in delaying a combustion control. In order to prevent this operation, prior to a starting of combustion, the water rate proportionally regulating valve is moved. So an adjusting time of the water rate proportionally regulating valve from a degree of opening of the initial setting to a degree or opening corresponding to the set temp. is shortened and so the fed-out hot water temp. can be rapidly set to the set temp..

Description

Combustion control method of hot water heater

1 is a schematic view showing a gas-fired hot water heater employing an embodiment of the present invention.

2 is a block diagram showing a gas-fired hot water heater employing an embodiment of the present invention.

3 to 5 are operational flowcharts related to the combustion control method of the gas-fired hot water heater adopting an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

1: gas combustion hot water heater 11: gas burner

13 heat exchanger 23 constant pressure proportional valve

24: replaceable solenoid valve 33: proportional adjustment valve

35: inlet temperature thermistor (inlet temperature detection means)

36: quantity sensor (inflow quantity detecting means) 50: controller

54: main controller (temperature setting means)

54a: sub-controller (temperature setting means)

60: control circuit 70: microcomputer (CPU)

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion control method for a hot water heater, in which an amount of water flowing into a heat exchanger is controlled by a proportional control valve, and is related to the initial setting of the proportional control valve.

Conventionally, an inlet temperature sensor for detecting the inlet temperature of the water flowing into the heat exchanger, a setting unit for setting the tapping temperature of the water flowing out of the soft exchanger, and an inflow amount of the water into the heat exchanger are adjusted according to the set tapping temperature and the inlet temperature. There is a water heater with a water controller.

The hot water supply is turned on, the operation switch is turned 'on', and the set tapping temperature is input, thereby adjusting the water quantity controller so that the set tapping temperature is obtained in the heat exchanger corresponding to the tapping temperature.

However, after the user inputs the set tapping temperature, the quantity controller of the hot water heater configured as described above compares the tapping temperature with the set tapping temperature until the tapping amount corresponding to the tapping temperature is reached to obtain a constant tapping temperature according to the tapping temperature. In order to determine the quantity, that is, the movement of the quantity controller takes time, and in the meantime, the ignition to the burner has to be waited for.

Accordingly, an object of the present invention is to provide a combustion control method for a hot water heater, which enables to set the quantity proportional control valve to precede the hot water temperature to reach the set temperature quickly.

The hot water heater, to which the method of the present invention is applied, includes a combustor case, a burner installed in the case, a heat exchanger installed in the case for heating the water passing through the burner, and a water installed upstream of the heat exchanger and introduced into the heat exchanger. An inlet temperature detecting means for detecting the inlet temperature, a tapping temperature detecting means for detecting the tapping temperature of the water flowing out of the heat exchanger, a storage means for storing the first set tapping temperature set in advance, and an input when the power is turned on Temperature setting means for setting a second set tapping temperature to be turned off and at the same time to be turned off, and to have a priority over the first set tapping temperature, and a flow rate of water into the heat exchanger. Equipped with a proportional adjustment valve that adjusts in response to the set tapping temperature or the second set tapping temperature and the inlet temperature, A configuration in which the quantity proportional adjustment valve is initially set such that the quantity corresponding to the first set tapping temperature is obtained is adopted.

The hot water heater to which the method of the present invention is applied has the following function by the above configuration.

The second set tapping temperature and the set tap by the input means after the initial value is set so that the amount of water corresponding to the first set tapping temperature stored by the memory means is obtained at the same time as the power is turned on. The proportionality adjustment valve is adjusted in accordance with the input value with the inlet temperature detected by the temperature detecting means.

The hot water heater to which the method of the present invention is applied exhibits the following effects by the above configuration and operation.

Since the quantity proportional adjustment valve can be set in advance than the setting of the second set tapping temperature inputted by the input means, the adjustment time of the quantity proportional control valve is shortened, so that the combustion control needs to have a movement time of the proportional regulation valve. And the tapping temperature can be quickly set to the second set tapping temperature.

The present invention will be described with reference to an embodiment of a gas combustion hot water heater in the case of using a gas fuel.

1 is a gas combustion hot water heater employing an embodiment of the present invention.

A combustor case 10 is installed in the hot water heater case 2 of the gas-fired hot water heater 1, and therein, a first burner 11a combusting the fuel gas supplied by the gas supply pipe 20. And a double burner 11 including a second burner 11b.

Moreover, the combustor case 10 is equipped with the combustion fan 12 using the brushless direct current (DC) motor of 3-phase Y connection, and the gas burner 11 is the combustion air supplied by this fan 12. And a forced blow type combustor which mixes and combusts the fuel gas supplied from the gas supply pipe 12 at a predetermined ratio, and exhaust combustion gas generated by the combustion is exhausted from the exhaust port 3 to the outside.

The heat exchanger 13 connected to the water supply pipe 30 is installed above the combustor case 10, and the water passing through the inside is heated by the heat of the flame and the combustion gas generated by the gas burner 11. do.

In the vicinity of the burner 11 in the combustor case 10, a sparker 14 as an ignition device and a frame rod 15 as flame detection means are provided.

The gas supply pipe 20 controls supply pressures of the original solenoid valve 21, the kettle valve 22, and the supply amount of fuel gas (hereinafter referred to as gas amount) that allow fuel gas to pass through when energized from the upstream side. And a proportional type gas proportional valve (hereinafter referred to as a constant pressure proportional valve: 23) and a switching solenoid valve (hereinafter referred to as a switching valve: 24) to shut off the fuel gas to the second burner 11b according to the use condition. Each of them is installed to supply fuel gas to the gas burner 11 described above.

A water discharge pipe 32 having a water filter 31 is installed at the uppermost part of the water supply pipe 30, and downstream thereof, a quantity proportional adjustment is performed by a geared motor that adjusts the inflow of water into the heat exchanger 13. A valve 33 is provided, and this proportionality regulating valve 33 is provided with a potentiometer 34 for detecting the opening degree.

The water whose inflow rate is adjusted in the quantity proportional adjustment valve 33 is immediately detected by the inlet temperature thermistor 35, which is an inlet temperature detection means installed downstream, and the inlet water quantity sensor 36, which is a downstream inlet quantity detecting means. ), The amount of water is detected and sent to the heat exchanger 13 through the water supply pipe (30).

The water supply pipe (30) downstream of the heat exchanger (13) is provided with a tapping temperature thermistor (38), which is tapping temperature detecting means for detecting the temperature of the heated water, and at the bottom of the tapping unit attached to the hot water supply place. (Not shown) is installed.

The hot water heater 1 having the above configuration is controlled by the controller 50.

As shown in FIG. 2, the control device 50 includes a control circuit 60 connected to a power cord 51 connected to an outlet for wiring and a main controller 54 for remotely operating the water heater 1. And a terminal for connecting the subcontroller 54a.

The main controller 54 and the sub-controller 54a are temperature setting means set by a user. In this embodiment, the main controller 54 is provided in proximity to the hot water heater 1, and the sub-controller 54a. Is installed in hot water places such as bathrooms.

That is, the main controller 54 and the subcontroller 54a are provided with respective operation switches 56 and 56a and water temperature setting switches 57 and 57a for setting tapping temperatures.

The control circuit 60 includes a sparker circuit 71, a fan driving circuit 72, a proportional valve control circuit 73, and a geared motor driving circuit 74, mainly with a microcomputer (hereinafter referred to as a CPU). There are a position detecting circuit 75 and a quantity detecting circuit 76, and these circuits are subjected to predetermined control by the CPU 70.

The fan driving circuit 72 rotates the fan 12 according to a combustion capacity such as a set temperature, and rotates it by a hole integrated circuit (IC) provided in a brushless direct current (DC) motor of a three-phase Y connection. The number is detected and the detection signal is sent to the CPU 70.

Then, the proportional valve control circuit 73 adjusts the amount of current supplied to the constant pressure proportional valve 23 for adjusting the supply amount of the fuel gas so that the combustion in the gas burner 11 is performed at a desired mixing ratio of air and fuel. The circuit is controlled based on a proportional control parameter suitable for the characteristic of the valve 23 (depending on the type of gas).

In addition, the proportional valve control circuit 73 proportionally controls the maximum value of the current with the constant pressure proportional proportional valve 23 to correct an error due to dispersion of the hot water heater 1 and a pressure loss due to gas type to obtain an appropriate gas amount. It has a semi-fixed volume.

The geared motor drive circuit 74 is a circuit for driving the geared motor of the proportionality control valve 33 for regulating the amount of water flowing into the heat exchanger 13, but does not operate when the power is turned off. In the state where the power is 'on', the operation switch 56a of the sub-controller 54a is set at the previous set temperature position regardless of 'on' or 'off', and the position according to the reference temperature at the position The initial value is set.

In addition, the position detection circuit 75 is a circuit for analyzing the signal from the provided potentiometer 34 in order to detect the opening degree of the proportionality control valve 33.

The quantity detecting circuit 76 detects the quantity of water obtained by the rotational speed signal of the quantity sensor 36.

On the other hand, the CPU 70 has a memory function for storing the reference temperature which is the first set tapping temperature set in the assembling step of the hot water heater 1 and the gas type of the fuel gas to be used, and the main controller 54 and the subcontroller ( 54a) discrimination function, sequence control for controlling the operation sequence and timing of the respective circuits, and combustion amount and water supply amount based on the set temperature which is the inlet temperature, the reference temperature or the second tapping temperature as the combustion capacity control. Based on the feed forward control (hereinafter referred to as FF control) and the tapping temperature, the amount of combustion and the quantity of water are automatically proportioned, such as the automatic adjustment of the amount of gas, the 'on' of the switching valve 24, and the amount of air flow of the 'off' fan 12. Integral control (hereinafter referred to as PI control) performs feedback control (hereinafter referred to as FB control), and FF → FB (PI) switching control to switch between FF control and FB control. A safety function is also provided.

In addition, when the set temperature is input by the user, the CPU 70 gives priority to the set temperature over the reference temperature, and controls the hot water heater 1 to approach the tapping temperature of the set temperature.

The set temperature can be changed every hour when the power is on, but is cleared (cancelled) when the power is off.

The discriminating function is a part that analyzes the pulse signal to perform control according to each set state of the main controller 54 and the subcontroller 54a connected to the terminals 61 and 62 of the control circuit 60, respectively. The terminal 61 and the stage 62 are 2-wire terminals of a wire type that can supply electricity to the main controller 54 and the sub-controller 54a.

In the sequence control, when the user opens the hot water supply and the water supply signal is obtained based on the quantity sensor 36, the fan 12 is operated and the ignition operation is performed after the pre-age for a predetermined time is performed.

In the ignition operation, the original solenoid valve 21, the kettle valve 22, the constant pressure proportional valve 23, and the sparker 14 are energized at the same time. After the ignition detection, the capacity calculation of the combustion amount is performed and the combustion corresponding to the set amount is performed. Begins.

On the other hand, when the water supply signal based on the water quantity sensor 36 is detected, the calculation of the amount of combustion starts at the same time based on the water inlet temperature thermistor 35, but the water temperature when the water temperature is not passed through the water supply pipe 30 is read. In this embodiment, the water temperature is read after the water supply signal is detected, and the water temperature at that time is the water temperature data.

In the combustion capacity control, the FF control and the FB control for detecting the tapping temperature and correcting the combustion amount and quantity are performed.

In addition, the FF control is performed by the first calculated value Q of the combustion capacity calculated from the set temperature, the inlet temperature, and the intake amount by the main controller 54 and the subcontroller 54a, and the q calculated in the intake temperature intake amount and the tapping temperature. Calculate the most efficient combustion capacity in the fan (12), constant pressure proportional valve (23), switching valve (24), quantity control valve (33), respectively, to automatically adjust the gas amount and water intake.

As a safety function, when the tapping temperature is above the boiling temperature and it continues for a predetermined time (t8; for example, 1-10 seconds), the continuous combustion is continued for a certain time (t7; for 40-120 minutes, for example) Alternatively, when no flame is detected, each solenoid valve is closed and operation is stopped.

The operation method of the control apparatus 50 in the hot water heater 1 which is a present Example is demonstrated based on the operation flowchart shown to FIG. 3 thru | or FIG.

When the hot water heater 1 is installed, the gas type of the fuel gas to be used as the gas type switching switch 55 is checked and a reference temperature (40 ° C. in this embodiment) is set (S ₁ ).

The gas type of the fuel gas and the setting of the reference temperature are already set at the time of installation of the hot water heater 1, so that the power is turned on and stored in the storage function of the CPU 70.

However, when the set temperature is input by the user, the CPU 70 controls the hot water heater 1 so as to approach the tapping temperature of the set temperature in preference to the set temperature.

In order to use the hot water heater 1, the power cord 51 is connected to a wiring outlet, and the power is turned on (S ₂ ).

Discriminates whether or not quantity proportional control valve 33, the reference temperature (in this embodiment, 40 ℃) a input quantity with a maximum quantity mouth there is initially set so open that can correspond to (S _3).

The proportionality control valve 33 is set to a predetermined opening degree of the set temperature (or reference temperature) when the hot water heater 1 was used last time regardless of whether the sub controller 54a is turned on or off.

However, the geared motor which changes the opening degree of the proportionality control valve 33 may require several seconds to move the input temperature to adjust the opening degree, so that the combustion control time may be encroached. The control is delayed.

In order to prevent this, in this embodiment, the quantity proportional adjustment valve 33 is moved before the start of combustion.

Therefore, since the adjustment time of the quantity-proportional adjustment valve 33 from the initial opening degree to the opening degree according to the setting temperature in the later FF control is shortened, the tapping temperature is quickly set to the setting temperature in the FF control. There is a number.

When it is set to the opening degree that can be the maximum amount of water corresponding to the combustion capacity, the geared motor is 'off' (S ₄ ).

When it is not set to the maximum opening amount, the geared motor is turned on (S ₅ ).

In general, the driving time of the proportionality control valve 33 is only a few seconds even if it is displaced to the maximum. However, if freezing or foreign matter is mixed, the proportionality control valve 33 is locked. In spite of the energization from the motor drive circuit 74, there is a case where the proportionality adjustment valve 33 is not displaced. As a result, the energization time becomes longer, resulting in combustion loss due to the heating of the motor or the geared motor drive circuit 74. There is a risk.

In this embodiment, even in such a case, the gearing time by the geared motor drive circuit 74 is 'off' for t1 (for example, 5-30 seconds) so that the device does not fail ( S ₆ ).

Subsequently, it is determined whether the operation switches 56 and 56a of the main controller 54 or the sub-controller 54a are 'on' (S ₇ ), and the above process (S ₇ ) until it is 'on'. To repeat.

When the above is 'on', it is determined whether or not the tapping temperature is set by the water temperature setting switch 57, 57a (S ₈ ).

Further, even after the predetermined time (t ₂ seconds) has elapsed (S ₉ ), when the tapping temperature is not set, the set temperature is set to 40 deg. C, which is the reference temperature (S ₁₀ ). Subsequently, when the user opens the hot water supply (S ₁₁ ), the water quantity sensor 36 detects the water supply amount (S ₁₂ ).

Here, the receiving method of receiving quantity change signal does not accept the minute change which is not detected by the quantity acquisition circuit 76, and accepts when the amount of variation of quantity is more than predetermined value compared with the current quantity of acquisition (normal flow). .

In the water quantity detection circuit 76 which reads the signal from the water quantity sensor 36, the signal is detected as a passing signal when the signal is equal to or higher than a predetermined voltage, but is read by the water quantity detection circuit 76 due to overflow of the water flow. An error occurs and chattering is prevented by providing hysteresis characteristics in the present embodiment, because setting the set voltage to a constant voltage causes chattering (vibration). When a small change such as 2.0 L / min or less occurs, it is not detected as a passing signal.

Normally, the amount of data obtained is updated at each sampling time. However, even when the accumulated value within a certain time becomes more than a predetermined value in consideration of the response delay of the quantity sensor 36, it is accepted as a change in the quantity of water obtained.

Therefore, not only the instantaneous amount of change of water can be detected but also the amount of change in the amount of water obtained at any time can be detected, and the amount of gas corresponding to the wide amount of change in water can be adjusted.

Then after detecting the input quantity has passed a predetermined time (t ₃ chogan) (S _13), it detects the temperature obtained by retrieving temperature thermistor (35) (S _14).

Then, it is determined whether the water temperature is 55 ° C. or higher (S ₁₅ ), and when the temperature is 55 ° C. or higher, the user closes the hot water supply (S ₁₆ ), and the operation switch 56 of the main controller 54 and the sub-controller 54 a is closed. , 56a is 'off' (S ₁₇ ).

In addition, when the temperature is lower than 55 ° C., it is determined whether the water temperature is lower than or equal to the set temperature (S ₁₈ ). When the temperature is higher than the set temperature, the operation of S ₁₂ or less is repeated. (S ₁₉ ).

The hall IC detects the rotation speed of the fan 12 (S ₂₀ ), and determines whether the rotation speed is greater than or equal to the predetermined rotation speed (S ₂₁ ). When the rotation speed is lower than the predetermined rotation speed, the rotation speed corresponding to the combustion capacity is determined. Since the solenoid valve 21, the kettle valve 22, the switching valve 24, the constant pressure proportional valve 23, and the fan 12 are all turned off (S _22-26 ), they are not obtained. After closing the front (S ₂₇ ), the operation switches 56, 56a of the main controller 54 and the sub-controller 54a 'off' (S ₂₈ ).

When the number of revolutions is greater than or equal to the predetermined number of revolutions, prephasing is performed for t ₄ (for example, 0.5-10) seconds (S ₂₉ ), the sparker 14, the solenoid valve 21, the kettle valve 22, and the switching valve All 24) 'on' (S _30-33 ), and supplies a moderate ignition current to the constant pressure proportional valve (23) (S ₃₄ ).

The amount of energization to the constant pressure proportional valve 23 is controlled based on the rotational speed of the fan 12, that is, the amount of air and the gas type KP, except at the time of ignition.

In the present embodiment, in particular, the ignition gas amount during ignition is set to be a constant ratio with respect to the maximum value of the current to the constant pressure proportional valve 23 adjusted by the semi-fixed volume of the proportional valve control circuit 73. This makes it possible to supply an appropriate moderate amount of ignition gas at the time of ignition.

After the sparker 14 is 'on', after t ₅ (for example, 5-20) seconds have elapsed (S ₃₅ ), the sparker 14 is 'off' (S ₃₆ ).

Then, the flame rod 15 detects the combustion flame, and the flame rod 15 determines whether or not a current of IA or higher is input (S ₃₇ ).

When a current of IA or more is not input in the above, it is judged as an ignition miss and repeats the operation of S ₂₂ or less.

When a current of IA or more is input, a gentle ignition timer of t ₆ (for example, 0.1-10) seconds is performed (S ₃₈ ), and the tapping temperature is detected by the tapping temperature thermistor 38 (S ₃₉ ).

Then it was subjected to combustion capacity control (S _40), it performs a safety function of the control or less.

It is discriminated whether or not the rotation speed of the fan 12 is greater than or equal to the predetermined rotation speed (S ₄₁ ). When the rotation speed is lower than the predetermined rotation speed, the operation of S ₂₂ or less is performed. It is determined whether a current of IA or more is input (S ₄₂ ). When a current of IA or more is input, continuous combustion may continue for t ₇ (eg 40-120) seconds (S ₄₃ ), and the tapping temperature will be above the boiling temperature so that it is t ₈ (eg 1-10) If it lasts for a second (S ₄₅ ), the operation below S ₂₂ is repeated.

The continuous combustion is within t ₇ seconds, and if the tapping temperature does not reach the boiling temperature, the set temperature is input again (S ₄₆ ) and the operation below S ₃₉ is repeated. S _{46 corresponds} to the case where the user changes the set temperature.

When no current of IA or more is input, a misfire state such as a fire extinguished by a wind lamp is detected, and it is determined whether the misfire during combustion is the first (S ₄₇ ), and when the misfire is the second, S ₂₂ or less Repeat the operation of.

When the misfire is the first time, the original solenoid valve 21, the kettle valve 22, and the switching valve 24 are 'off' (S _48-50 ), and then the operation of S ₁₉ or less is repeated.

In this embodiment, gaseous fuel such as fuel gas is used as fuel, but liquid fuel such as petroleum may be used as fuel.

As described above, according to the method of the present invention, the initial value is set so that the amount of water in proportion to the first set tapping temperature stored at the same time as the power source 'on' is obtained by the storage means. The tapping temperature reaches the set temperature quickly because it is adjusted according to the input value of the second set tapping temperature set by the means and the tapping temperature detected by the inlet temperature detecting means.

Claims (1)

The combustor case 10, the burner 11 installed in this combustor, the heat exchanger 13 which heats the water which is installed in the case 10 and passes through it by the burner 11, and this heat exchanger 13 Inlet temperature detection means (35), which is installed upstream of the sensor and detects the inlet temperature of water flowing into the heat exchanger (13), and the tapping temperature detection means (38) for detecting the tapping temperature of the water flowing out of the heat exchanger (13). A hot water supply machine comprising: a storage means for storing a first set tapping temperature which is set in advance, a first input when the power is 'on' and immediately erased when the power is 'off', and which is prior to the first tapping temperature Temperature setting means (54) and (54a) for setting the set tapping temperature of 2 and the amount of water flowing into the heat exchanger (13) corresponding to the first set tapping temperature or the second set tapping temperature and the inlet temperature And the proportionality control valve 33 to adjust the power supply 'on' and And at the same time, an initial value is set so that the quantity proportional control valve (33) obtains an amount of water corresponding to the first set tapping temperature.

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