KR930010394B1 - Flow control method of hot-water supply apparatus - Google Patents

Abstract

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Description

Flow control method of hot water heater

1 is a flow chart for explaining the water circuit control operation by the control device in the gas hot water bath system showing an embodiment of the present invention.

2 is a schematic configuration diagram of a gas hot water bath system according to an embodiment of the present invention.

3 is a functional block diagram of a control device according to an embodiment of the present invention.

4 is a flow chart for explaining the flow rate control by the control device according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

4: hot water burner (heating means) 10: water pipe (water circuit)

11: main heat exchanger (heat exchanger) 14: hot water pipe (water circuit)

15: flow rate servo (flow control means) 31: flow rate sensor (flow detection means)

32: water supply temperature thermistor (intake temperature detection means)

50: control device (flow control device of the hot water heater) 60: remote control (temperature setting means)

The present invention relates to a flow rate control method of a hot water heater for controlling the flow rate by controlling the flow rate control device according to the water temperature flowing into the water circuit including the heat exchanger.

In general, in a hot water heater, the maximum heating capacity obtained by a gas burner for heating the water passing through the heat exchanger is limited. Therefore, in a water circuit including a heat exchanger, the flow rate is controlled by driving a valve body by, for example, a geared motor. If the target temperature is not obtained and the target temperature is not obtained, the flow rate of the water passing through the heat exchanger is limited so that the hot water flowing out reaches the target temperature.

In addition, the maximum flow rate corresponding to the maximum heating capacity of the gas burner, etc. is calculated in advance from the target temperature and the supply temperature to the heat exchanger in order to obtain not only flow rate limitation but also as much flow rate as possible for the target temperature. The flow regulating device is controlled so that the maximum flow rate is obtained, and the operation of increasing the flow rate for obtaining the calculated capacity is also performed.

However, a mixture stopper may be installed in a bathroom and a sink in a general home to mix hot water from a hot water supplyer and water directly supplied from a tap water, and the mixture stopper may be set to a temperature desired by a user. It is equipped with a thermo valve which can automatically adjust the mixing ratio of the temperature from and the water from the tap water.

When hot water supply or water filling is performed using the mixture stopper with the thermovalve, the amount of hot water is regulated regardless of the control state of the hot water dispenser, so that the maximum flow rate calculated at the hot water supply side can be obtained. Even if the water temperature is adjusted, the hot water flow rate changes according to the hot water temperature to the mixture stopper.

As a result, on the hot water heater side, the opening state of the once-adjusted flow regulator is changed again so that the proper flow rate is changed. On the mixture plug side, the hot water flow rate is adjusted by receiving the re-regulation of the flow rate by the flow regulator. When this operation is repeatedly performed, the flow rate becomes unstable and the tapping temperature is changed according to the fluctuation of the flow rate, so that the flow rate and tapping temperature are not always stable and cause temperature hunting. .

Similarly, even when hot water supply is performed with a general water stopper, if the hot water supply flow rate is limited according to the user, the flow rate is unstable because the flow rate is controlled by the flow rate control device.

According to the present invention, when the hot water supply flow rate is limited by the user in the flow rate control device of the hot water heater in which the target amount is calculated in advance so as to obtain as much hot water flow rate as possible corresponding to the set temperature and the flow rate adjusting means is controlled to obtain the flow rate. The purpose is to stabilize the flow rate and tapping temperature.

The present invention is to set the temperature for the hot water flowing out of the water circuit including the heat exchanger heated in the heating means by the temperature setting means at the time of hot water supply to achieve the above object, the water supply temperature detection means detects the water supply temperature Calculating a target flow rate in a control means based on the set temperature and the water supply temperature detected, controlling the flow rate adjusting means so that the flow rate detected by the flow rate detection means becomes a target flow rate, Determining whether the set temperature is changed within a predetermined time after the start of hot water supply and recalculating the target flow rate when the set temperature is changed, and when the tapping temperature does not reach the set temperature after the predetermined time, the flow rate reducing operation is performed. The flow rate adjusting step includes adjusting the flow rate according to the target flow rate until a predetermined time elapses after the start of hot water supply. Controlling the stage, and so that a predetermined time has passed after not performing control of the flow rate adjusting device in accordance with the target flow rate by technical means.

According to the present invention configured as described above, when the hot water supply is started, the maximum flow rate is calculated according to the heating capacity of the heating means according to the water supply temperature, and the flow rate adjusting means is controlled to obtain the flow rate.

The flow rate control control by the flow rate adjusting means performed based on this target flow rate is performed until a predetermined time elapses after the start of hot water supply, and is not performed after a predetermined time elapses.

Therefore, when the flow stopper is required to have as much flow rate as possible and the water filling valve is opened, and when the water filling valve is opened for filling, the flow rate is adjusted as much as possible by adjusting the flow rate during this predetermined time. Heating takes place.

On the other hand, when the user restricts the flow rate with a water stopper or the flow rate is regulated by a thermo valve, the flow rate and tapping temperature are generally unstable because the operation for increasing the flow rate is performed by the flow rate adjusting means for a predetermined time. In the initial hot water supply, the tapping temperature is difficult to stabilize, so there is no significant effect.

In addition, if a predetermined time elapses, the flow rate adjustment by the flow rate adjusting means according to the target flow rate is not performed. If the flow rate is controlled as necessary, the flow rate is stabilized and the tapping temperature is stabilized in accordance with the flow rate stability.

In the present invention, when a large flow rate is required, the flow rate adjusting means is controlled according to the target flow rate for a predetermined time after the hot water supply is started, and the hot water supply can be performed at the flow rate as much as possible with respect to the set temperature. Hot water supply can be continued even after that.

In addition, since the flow rate adjusting means is not controlled according to the target flow rate after a predetermined time has elapsed, the flow rate adjusting device no longer changes the flow rate to the target flow rate as opposed to the operation of the water stopper and the operation of the thermo valve. This becomes stable, and the tapping temperature is stabilized accordingly.

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

The gas hot water bath system 1 shown in FIG. 2 is a complex hot water supply system having an automatic water filling function and additional heating, and heats water passing through a water pipe 10 connected to a water supply source such as tap water. A main heater 2 for hot water supply to the plurality of hot water supply ports A and the bath B, a bath tub heater 3 for circulating and heating the hot water in the bath B, ie, a temperature, and each of these heaters 2 ), (3), a hot water supply hole A, and the bathtub B are connected, and it consists of several piping which forms a water circuit.

In order to detect the flow rate of the water passing through the water pipe 10, the flow sensor 31 which detects the rotation of the impeller rotating in accordance with the flow rate by generating the pulse signal and the water supply temperature which detects the supplied water supply temperature Tin, The thermistor 32 is provided, and the water pipe 10 branches downstream of the flow sensor 31 and the feed water temperature thermistor 32 so that one side is connected to the main heat exchanger 11 of the main heater 2 and the other. The side is a bypass pipe 12 bypassing the main heat exchanger 11, and the bypass pipe 12 is provided with a bypass solenoid valve 13 to be opened as necessary.

In the tapping pipe 14 where the main heat exchanger 11 and the bypass pipe 12 are joined, an electric tapping water supply unit 15 and a tapping water valve driven by a geared motor to limit the amount of tapping outflow. A tapping temperature thermistor 33 for detecting the temperature Tout is provided, and the tapping pipe 14 branches downstream of the tap water supply servo 15 and the tapping temperature thermistor 33 so that one side is hot water supply for each hot water inlet A. It becomes the pipe 16 and the other side becomes the connection pipe 17 with respect to the bath heater 3.

The connection pipe 17 has a water quantity sensor 34 for detecting the water filling amount, a vacuum circuit breaker 35 which opens the hot water supply circuit to the atmosphere so as to prevent water from flowing back in the water at the time of watering, when water is filled. The water filling valve 18 which consists of a ball valve which becomes an open state, and the two non-return valves 19 and 19a which prevent the backflow of the hot water in the bathtub B are provided.

The connecting pipe 17 is branched into two upstream of the bath heater 3 so that one side becomes the water filling pipe 20 for the bath B and is connected to the bath B, and the other side is the bath tub of the bath heater 3. It is connected to one side of the heat exchanger 21.

The other side of the bath heat exchanger 21 is a circulation pipe 22 connected to the bath B in the same manner as the water filling pipe 20 in order to circulate the hot water from the bath B, and the circulation pipe 22 ), The water level sensor 36, the pump 23, the on-off valve 24, the water flow switch 37, and the bath tub thermistor 38 are provided in order from the bath B side.

The water level sensor 36 is composed of a semiconductor diffusion resistance type pressure sensor using a piezoresistive effect, and is assembled in a diaphragm chamber in which one side is in communication with the circulation pipe 22 and the other side is open to the atmosphere, The resistance value according to the water level can be detected.

When the pump 23 is energized, the pump 23 is rotated at a constant rotational speed to pump the hot water in the tub B from the circulation pipe 22 to the bath heat exchanger 21 and to the tub B again from the water filling pipe 20. Will be cycled.

The on-off valve 24 is a rotary valve for driving a pipe-shaped valve body through which the hot water can pass in any direction by a servo motor. The circulation pipe 22 is formed by the circulation pipe 22 and the water filling pipe 20, and the circulation pipe at the time of stopping the pump 23 in order to detect the water level by the water level sensor 36 ( 22) will be closed.

In addition, the on-off valve 24 is opened at the time of water filling by the main heater 2, so that water can be filled not only from the water filling pipe 20 but also from the circulation pipe 22.

The water flow switch 37 is for detecting whether or not the water flows through the circulation pipe 22 when the pump 23 is operated. The water flow switch 37 does not detect the water flow when the water flow is reversed.

The bath tub thermistor 38 detects the temperature of the hot water in the bath B when the pump 23 is operated. The main heater 2 burns by the hot water burner 4 when water passes through the water pipe 20 to heat the main heat exchanger 11.

The fuel pipe 40 for the hot water burner 4 is provided with a solenoid valve 40a for stopping all fuel supply, and a downstream governor proportional valve 41 for adjusting the fuel supply amount according to the required heating amount. The solenoid valves 42 and 43 which control the number of burners to be used among all the burners of the hot water supply burner 4 are installed, and the hot water burner 4 supplies the fuel gas regulated by these solenoid valves 42 and 43 to the hot water supply. Combustion is performed by mixing with the air for fuel supplied by the blower 44.

The bath tub heater 3 burns fuel gas supplied from the bath tub fuel pipe 45 branched from the fuel pipe 40 at the bath tub burner 5 by the combustion air supplied by the bath tub blower 46 to exchange the bath heat. The group 21 is heated.

In addition, the bath barrel fuel pipe 45 has a governor 47 for maintaining a constant supply gas pressure and a bath barrel solenoid valve 48 for supplying fuel, and a solenoid valve for controlling the number of burners used for the bath barrel burner 5. 49 are provided, respectively.

Gas hot water bath system (1) having the above configuration is controlled by the control device 50, the control device 50 is configured around the microcomputer, the functional configuration is shown in FIG. The hot water supply control unit 51 for controlling the main heater (2), the bath tub control unit (52) for controlling the bath heater (3) and the water circuit control unit (53) for controlling the water circuit are largely divided into hot water supply temperature or water filling It is provided with a remote controller 60 for indicating the setting of the temperature and the water filling amount and the operating state.

The remote controller 60 is provided with a plurality of operation switches for instructing hot water supply or a desired type of water filling, and a setting switch for setting a set temperature Tset, water filling amount, and time for water filling in each operation. In addition, a display unit for displaying each setting state and the current time, etc., and a buzzer operating at the end of filling the water are provided.

The hot water supply control unit 51 supplies the hot water supply blower 44, the solenoid valve 40a, the solenoid valves 42, 43, and the hot water burner 4 according to the water supply information by the flow sensor 31 when hot water supply or water filling is performed. Ignition control of the hot water supply burner 4 by controlling the ignition electrode 4a provided at the predetermined temperature, and the detection temperature of the water supply temperature thermistor 32 and the tapping temperature thermistor 33 The required heating amount by the hot water burner 4 is calculated from the detected flow rate of the flow rate sensor 31 and the set temperature Tset by the remote controller 60, and the hot water supply fan 44 is controlled based on the required heating amount. By controlling the governor proportional valve 41 by detecting the rotational speed of the blower 44, the solenoid valve 42 is controlled to control the combustion amount of the hot water burner 4.

Moreover, fire extinguishing control is performed based on the water flow stop information of the flow sensor 31.

During the training, flame detection is performed by the frame rod 4b provided in the hot water burner, and in the event of a fire, the solenoid valves such as the solenoid valve 40a are closed to stop fuel supply to stop combustion.

When the bath temperature is detected by the bath thermistor 38 every predetermined time after the water filling is finished in the case of the fully automatic operation, when the bath temperature is lower than the set temperature Tset, the bath ventilator 46 is in a predetermined sequence. Ignition control of the bath tub burner 5 by controlling the ignition electrode 5a provided in the bath tub solenoid valve 48 and the bath tub burner, and the water flow in the bath tub circulation path is controlled by the operation of the pump 23. Heating while being detected by), and this heating is performed until the hot water circulating in the bath circulation circuit rises to the set temperature Tset.

The combustion amount of the bath tub burner 5 during combustion is determined by the solenoid valve 49 controlled according to the temperature difference between the detection temperature and the set temperature Tset.

Moreover, the flame of the bath tub burner 5 is detected by the frame rod 5b provided in the bath tub burner 5, and when a misfire occurs, fuel supply is stopped and combustion is stopped.

The water circuit control unit 53 performs hot water supply control or water filling control in a predetermined sequence according to the instruction from the remote controller 60, and at this time, the hot water supply amount is obtained as much as possible by heating at the maximum combustion amount of the hot water burner 4. , Based on the maximum heating amount of the hot water burner (4), the set temperature Tset by the remote control 60, the water supply temperature Tin in the water pipe (10) detected by the water supply temperature thermistor (32) to enable rapid filling of water The target flow rate Fo as the maximum flow rate heatable at the set temperature Tset is calculated, and the flow rate servo 15 is adjusted so that the flow rate F detected by the flow rate sensor 31 becomes the target flow rate Fo.

In this case, in order to reduce the fluctuation of the tapping temperature Tout, the water supply temperature Tin detected by the water supply temperature thermistor 32 is stored at the beginning of the hot water supply or the filling, and the target flow rate is determined by the stored water supply temperature Tin and the set temperature Tset. Fo is calculated, and then the target flow rate Fo is not changed even if the water supply temperature Tin changes.

In addition, when the flow rate servo 15 is controlled according to the calculated target flow rate Fo, the flow rate of the target flow rate Fo or more is detected, and when the flow rate reducing operation is performed once, the flow rate increasing operation is performed even if a flow rate F smaller than the target flow rate Fo is detected thereafter. The flow control operation is restricted so as not to perform the process.

In addition, the restriction of the flow rate adjustment operation is carried out only while the hot water supply or the water filling is continued, and once the hot water supply or the water filling is finished, the flow rate adjusting operation is performed again. The flow increase operation is performed.

In addition, even when hot water supply or water filling is continued, even if the set temperature Tset by the remote controller 60 is changed and the target flow rate Fo is changed and calculated again, the flow rate adjusting operation is performed in accordance with the new target flow rate Fo.

Then, the change of the set temperature Tset is monitored for a limited time until a predetermined time t, for example, 30 seconds elapses after the start of hot water supply or water filling, and after the predetermined time t has elapsed, the flow rate by the target flow rate Fo The adjustment control is not performed at all.

After the predetermined time t has elapsed, the flow rate control control is performed based on the tapping temperature Tout detected by the tapping temperature thermistor 33, and the flow rate increasing operation is performed only when the tapping temperature Tout does not reach the set temperature Tset. The operation is not performed at all.

As a result, for example, when a mixture stopper having a thermovalve directly supplied with water from a tap water or the like is provided as a hot water inlet A, the amount of hot water supply is changed for temperature control by the thermovalve. Even if the flow rate is changed, the flow rate control control on the side of the water supply servo 15 cannot be performed correspondingly, so that the amount of water does not become unstable forever due to the interaction between the thermo valve and the water supply servo 15. There is no change in tapping temperature Tout due to the change, and since only the heating amount of the hot water burner 4 is controlled, a stable tapping temperature Tout can be obtained.

The control flow of the water circuit control unit 53 at the beginning of the filling of water will be described below with reference to FIG. 1 by taking the case of the filling of water as an example.

When the water filling valve 18 is opened according to the instruction from the remote controller 60 and the water filling is started, the target flow rate Fo is calculated according to the set temperature Tset and the water supply temperature Tin (step 1), and according to the calculated target flow rate Fo. The hot water level servo 15 is driven to perform the flow rate control so as to obtain the target flow rate Fo (step 2).

Then, if there is a change in the set temperature Tset during the hot water supply or the water filling process (YES in step 3), the process proceeds to step 1 to calculate the target flow rate Fo, and the flow rate adjustment control is performed in accordance with the new target flow rate Fo.

The reflow of the target flow rate Fo in accordance with the change of the set temperature Tset is performed only after the start of water filling and until a predetermined time t elapses (NO in step 4).

If the set temperature Tset has not been changed (NO in step 3) and the predetermined time t has elapsed since the start of filling the water (YES in step 4), the tapping temperature Tout was compared afterward by comparing the set temperature Tset with the tapping temperature Tout. Only when this set temperature Tset is not reached (NO in step 5), the flow rate reduction operation is performed (step 6), so that the tapping temperature Tout can be surely heated to the set temperature Tset.

On the other hand, when the tapping temperature Tout reaches the set temperature Tset (YES in step 5), even if the heating capacity of the hot water burner 4 is sufficient, the flow rate increasing operation is not performed and the flow rate is maintained. As a result, the output flow rate can be stabilized and hot water fluctuation caused by the flow rate change can be prevented.

Thereafter, until the water filling amount reaches the set amount (NO in step 7), a comparison between the set temperature Tset and the tapping temperature Tout in step 5 is performed, whereby only the flow rate reducing operation (step 6) is performed.

When the water filling amount reaches the set amount (YES in step 7), the water filling is finished and the control to keep warm (step 8).

Next, the flow rate control in step 2 will be described with reference to FIG.

Here, the flow rate F detected by the flow rate sensor 31 is compared with the calculated target flow rate Fo, and if the flow rate F is the target flow rate Fo (＂= 에서 in step 11), the step without driving the hot water level servo 15 for adjusting the flow rate is performed. Go to 3.

If the flow rate F is larger than the target flow rate Fo (＂>＂ in step 11), the flow rate reducing operation by the hot water level servo 15 is performed (step 12).

The hot water supply servo 15 is driven while the flow rate F detected by the flow rate sensor 31 is equal to or higher than the target flow rate Fo (NO in step 13), and when the flow rate F detected by the flow rate sensor 31 becomes lower than or equal to the target flow rate Fo, (YES in step 13), the flow rate control is terminated and the process proceeds to step 3.

On the other hand, when the flow rate F is smaller than the target flow rate Fo (＂<＂ in step 11), the flow rate increasing operation by the hot water supply servo 15 is performed (step 14), and then, the flow proceeds to step 11 and repeatedly discriminated.

As a result, the hot water flow rate servo 15 is driven while the flow rate F is smaller than the target flow rate Fo.

In addition, in the comparison between the flow rate F in step 11 and the target flow rate Fo, in order to achieve stability of the operation of the water flow rate servo 15, a constant width is provided as the target flow rate Fo, and the water flow rate servo 15 is driven. In order to drive the hot water level servo 15 to the target flow rate Fo quickly and to obtain a sufficient driving torque for water pressure, the applied voltage to the geared motor of the hot water level servo 15 is kept constant, and the flow rate sensor 31 The voltage is continuously applied until the detected flow rate F becomes the flow rate F within the predetermined range with respect to the target flow rate Fo, while when the detected flow rate F is within the predetermined range, the pulses of the same voltage are applied at intervals to gradually change to the target flow rate Fo.

However, in order to increase the flow rate, the flow rate F is always set to the target flow rate Fo even if the flow rate F is stopped when the flow rate F becomes the target flow rate Fo, for example, due to the influence of the output of hot water passing through the flow rate servo 15. Although this may not be possible, in the present embodiment, when the flow increase operation is performed (step 14), the flow advances to step 11, so that the flow decrease operation in step 12 can be performed after the flow increase operation. This set temperature Tset is not reached.

On the contrary, once the flow rate reduction operation is performed to prevent excess flow rate F, even if there is room for the heating power of the hot water burner 4, the flow rate increase operation is not performed. Therefore, the flow rate F can be stabilized. As a result, the change in flow rate affects the tapping temperature Tout and does not change the hot water temperature.

The water circuit controller 53 opens the bypass solenoid valve 13 by opening the bypass solenoid valve 13 when the hot water flow rate is required both at the time of hot water supply and water filling, when the set temperature Tset is relatively low and the load of the hot water burner 4 is small. The hot water is led to the hot water supply pipe 14, and the hot water is burned in the largest possible amount of combustion by utilizing the heating capacity of the hot water burner 4, thereby performing a large amount of hot water in a short time.

In the automatic water filling control, when water is filled for the first time after completion of the installation work, a predetermined water filling quantity calculation control is performed, and the hot water supply amount Wa corresponding to the set water level is calculated and stored according to each bath.

Also, in the case of filling water after the second time in which water supply quantity Wa according to the bathtub is stored after the water filling quantity calculation control is completed, the water filling valve 18 is opened when the water filling instruction is given from the remote controller. The amount of water filling W is integrated by the water quantity sensor 34 while the water filling in the bathtub B is started and the water supply amount Wa according to the set water level is reached, and after the predetermined water supply amount Wa becomes The water level sensor 36 detects the actual water level and detects whether or not the water level has been set, and closes the water filling valve 18 when the water level is continuously set until the water level is reached.

In this water filling control, especially when there is room for hot water supply capacity, the opening / closing valve 24 is opened and closed in a predetermined sequence with respect to the water filling valve 18 in order to speed up the water filling time. Opening / closing valve 24 is opened so that water can be filled from circulation pipe 22 while preventing it from being applied to 36).

As described above, in the gas hot water bath system 1 of the present embodiment, when the hot water supply or the water filling is started, the flow rate decrease operation is performed once, and the flow rate is limited, except that the set temperature Tset is changed thereafter. Since the increase operation is not performed, the flow rate does not become unstable due to the fluctuation of the water supply temperature Tin.

In addition, since the flow rate is limited by performing the flow rate reducing operation, the tapping temperature Tout can be reliably set to the set temperature Tset.

Moreover, even if the water supply temperature Tin changes, the flow rate adjustment is not performed accordingly, so that the tapping temperature Tout can be stabilized.

On the other hand, when the set temperature Tset is changed, the tapping temperature Tout can be set to the set temperature Tset because the flow rate is adjusted accordingly.

In addition, even if the heating power shortage occurs due to the change in the water supply temperature Tin, and the required tapping temperature cannot be obtained, the flow rate can be adjusted by changing the set temperature so that the required temperature can be set.

Furthermore, after a certain time has elapsed since the start of hot water supply or water filling, the flow rate adjustment operation according to the target flow rate is not performed. For example, the hot water is automatically heated by a thermo valve according to the temperature at the hot water supply port A. Even if the amount is adjusted, the flow rate does not become unstable due to the interaction between the thermovalve and the hot water servo 15, and as a result, the tapping temperature can be stabilized.

In the said embodiment, although the bypass pipe 12 which bypasses the main heat exchanger 11 was installed in the main heater, the bypass pipe 12 may be absent.

Moreover, in the said Example, although the water supply temperature thermistor 32 was provided in the upstream water pipe 10 of the main heat exchanger 11, the tapping temperature thermistor 32 may estimate water supply temperature.

In the above embodiment, the gas hot water bath system is shown, but the present invention can also be applied to a burner by other fuel such as petroleum or a hot water supply device by heat transfer.

Claims (1)

Setting a temperature for hot water flowing out of a water circuit including a heat exchanger heated by the temperature setting means 60 by the temperature setting means 60 during hot water supply; Detecting the water supply temperature by the water input temperature detecting means 32; Calculating a target flow rate in the control means (50) based on the set temperature and the detected water supply temperature; Controlling the flow rate adjusting means (15) so that the flow rate detected by the flow rate detecting means (31) becomes a target flow rate; Determining whether the set temperature is changed within a predetermined time after the start of hot water supply and recalculating the target flow rate when the set temperature is changed; When the tapping temperature has elapsed, the flow rate reducing operation is performed when the tapping temperature does not reach the set temperature. (15) control, and after the predetermined time has elapsed, the flow control method of the hot water heater, characterized in that the control of the flow rate adjusting means 15 is not performed.