KR930007399B1 - Temperature control device for hot water supplier - Google Patents

Abstract

This system comprises a temperature sensor (25), a flow- sensor (19) to check the water passing through heat exchanger (13), a temperature estimater (35) to estimate the temperature of the coming-in-water, a memory (36) to store the temperature. When the temperature read by the sensor (25) doesn't change, this system replaces the stored temperature in the memory (36) after checking the coming-in-water temperature.

Description

Temperature controller of hot water heater

1 is a flow chart for explaining the operation of the water intake temperature in the control device of the gas water heater according to an embodiment of the present invention.

2 is a schematic view showing a gas-fired hot water heater according to an embodiment of the present invention.

3 is a functional block diagram showing a functional configuration relating to an intake temperature estimation operation of a control device of a gas-fired hot water heater illustrating an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

19: flow rate sensor (water flow detection means) 25: tapping temperature thermistor (temperature sensor)

30: controller (temperature controller of the hot water heater)

35: intake temperature calculation unit (intake temperature estimation means)

36: memory (estimated temperature storage means)

The present invention is a temperature sensor for detecting the water temperature, the temperature of the hot water heater provided with only the outflow temperature sensor for detecting the temperature of the hot water flowing out of the heat exchanger and the inlet temperature sensor for detecting the temperature of the water flowing into the heat exchanger The present invention relates to a control device, and more particularly, to a temperature control device of a hot water heater that effectively estimates an inlet temperature of a heat exchanger of a heat exchanger based on a detection temperature of an outflow temperature sensor in order to perform feedforward control. Japanese Patent Application Laid-Open No. 63-153361 simplifies the manufacturing process by simplifying the structure of the hot water heater and omits the installation of a temperature sensor that detects the inlet temperature flowing into the heat exchanger to reduce the manufacturing cost. A temperature control device having a temperature control function of feedforward to obtain tapping characteristics is disclosed.

The temperature control device stores the temperature of the hot water flowing out of the heat exchanger detected by the tapping temperature sensor in the storage means when the flow rate sensor installed in the water supply passage detects the hot water supply. Feedforward control is performed.

In general, however, in the case of re-hot water which stops the hot water supply once and performs the hot water supply again, since the stagnant water in the heat exchanger is heated by the extra heat, the temperature of the hot water flowing out of the heat exchanger and detected by the tapping temperature sensor is It is very different from the water inlet temperature.

Therefore, according to the above invention, since the outflow temperature of the hot water heated by the excess heat at the start of the refueling is stored as the inlet temperature for feedforward control as it is, on the basis of a temperature which is significantly different from the actual inlet temperature. The feedforward control is performed, thereby causing a problem that an appropriate amount of heating cannot be obtained.

SUMMARY OF THE INVENTION An object of the present invention is to provide a temperature control apparatus for a hot water heater, which has a feedforward control function to stably control the temperature even at the same time, while reducing costs by simplifying the structure of the hot water heater by omitting the inlet temperature sensor.

According to a first aspect of the present invention, there is provided a temperature sensor installed at an outlet of a heat exchanger, water flow detection means for detecting water passing through the heat exchanger, and a detection temperature of the temperature sensor when the water flow detection means detects the start of hot water supply. Acquisition temperature estimating means for estimating an intake temperature to the heat exchanger based on the estimated temperature storage means; and an estimated temperature storage means for storing an estimated temperature estimated by the acquisition temperature estimating means, the storage temperature stored in the estimated temperature storage means; In the temperature control device of the hot water heater for controlling the heating amount of the heating means of the heat exchanger, the inlet temperature estimating means is a temperature detected by the temperature sensor when the water flow detection means detects the start of hot water supply The technical means for estimating the intake temperature only if it does not change and replacing the storage temperature of the estimated temperature storage means with the technical means. do.

According to a second aspect of the present invention, there is provided a temperature sensor provided at an outlet of a heat exchanger, water flow detection means for detecting water passing through the heat exchanger, and a detection temperature of the temperature sensor when the water flow detection means detects the start of hot water supply. Acquisition temperature estimating means for estimating an intake temperature to the heat exchanger based on the estimated temperature; and an estimated temperature storage means for storing an estimated temperature estimated by the intake temperature estimating means, the storage temperature stored in the estimated temperature storage means; In the temperature control device of the hot water heater for controlling the heating amount of the heating means for heating the heat exchanger based on the above, the water temperature estimating means estimates the detection temperature as the water temperature when the detection temperature is lower than the storage temperature; If the detection temperature is higher than the storage temperature, a part of the temperature difference between the detection temperature and the storage temperature is considered. The temperature is added to the storage temperature, in that technical means that estimate to the obtained temperature.

In the first invention of the present invention, when the hot water supply is started and the start of the hot water supply is detected by the water flow detecting means, whether or not the temperature detected by the temperature sensor is determined is determined, and the intake temperature is estimated only when the detection temperature does not change. This estimated temperature is stored. Therefore, as in the case of refueling, when the water in the heat exchanger is heated by the extra heat and the tapping temperature fluctuates so that the detected water temperature is different from the actual water temperature, the fresh water temperature is not estimated and the memory temperature is replaced. It doesn't work.

In general, since the hot water heater can be used every day or can be used repeatedly without a large period of time, the acquisition temperature for each use is not significantly different from the acquisition temperature for the previous use. Therefore, even though the temperature is controlled based on the stored temperature, the heating amount is not controlled based on the wrongly obtained water temperature information, and the heating amount is controlled based on the temperature close to the actual temperature. Can be.

In the second invention, when the detection temperature at the start of the hot water supply is lower than the stored temperature, the detection temperature is likely to be the actual acquisition temperature. Therefore, the detection temperature is estimated as the acquisition temperature as it is, and the detection temperature is stored. When the temperature is higher than the temperature, the case of re-hot water can be considered. Therefore, the detection temperature is not estimated as the acquisition temperature as it is, and a part of the temperature difference between the stored temperature and the detection temperature is estimated as the acquisition temperature. Accordingly, even when a high temperature is detected by the hot water supply, it is not controlled by an inappropriate heating amount based on wrong temperature information.

In addition, even when the actual acquisition temperature increases with the change of the season, the temperature higher than the temperature already stored is assumed to be the acquisition temperature, and the storage temperature is replaced by a higher temperature. The temperature can be increased. Therefore, an appropriate acquisition temperature is estimated throughout the year, and an appropriate acquisition temperature is stored, so that it can be controlled by an appropriate heating amount.

EXAMPLE

Hereinafter, the temperature control device of the hot water heater of the present invention will be described based on the embodiment shown in the accompanying drawings.

The burner group 11 arrange | positioned by the some burner is provided in the combustor case 10 of the gas-fired hot water heater 1 shown in FIG. In the lower part of the combustor case 10, the blower 12 for supplying combustion air to the burner group 11 is provided. A water pipe type heat exchanger 13 is provided above the burner group 11 in the combustor case 10, and water passing through the inside thereof is heated by the combustion heat of the burner group 11. In the vicinity of the burner group 11 in the combustor case 10, a sparker 14 for igniting the burner group 11 and a flame rod 15 for detecting the ignition of the burner group 11 are provided. In addition, an exhaust port 2 for discharging combustion exhaust gas to the outside is provided above the combustor case 10.

An exposure tube 16 for supplying fuel gas is provided below the burner group 11, and a plurality of fuel outlet ports for ejecting fuel gas corresponding to the burners of the burner group 11 are respectively provided in the exposure tube 16. 16a) is installed.

The fuel pipe 20 for guiding the fuel gas to the exposure pipe 16 has two solenoid valves 21 and 22 for passing the fuel gas at the time of energization, and controls the supply amount of fuel gas by controlling the supply pressure in response to the energization current. Proportional valves 23 are provided in turn from the upstream side.

The water supply pipe 17 which guides the water from the supply source (not shown) to the heat exchanger 13 has a flow rate for detecting the amount of water passing through the electric water flow controller 18 and the heat exchanger 13 for adjusting the amount of hot water. Sensors 19 are sequentially installed from the upstream side, and hot water flowing out of the heat exchanger 13 is supplied to the hot water pipe 17a for guiding hot water flowing out of the heat exchanger 13 to a hot water supply port (not shown). A tapping temperature thermistor 25 for detecting the temperature T out is provided.

The control device 30 is provided with a control circuit centered on a microcomputer and performs the start and stop of combustion in a predetermined procedure, and simultaneously controls the temperature of the tap water according to the functional configuration shown in FIG.

In the controller 30, the temperature controller 31 for controlling the temperature based on the target temperature T set includes a feedforward controller (FF controller) 32 and a feedback controller (FB controller) 33, respectively. And a feed forward control as well as feedback control based on the detection temperature T of the tapping temperature thermistor 25.

In the apparatus of the present invention, since the thermistor as a temperature sensor is not provided in the water supply pipe 17, the acquisition temperature Tin for feedforward control cannot be detected directly. If the water is not heated by the heat exchanger 13, the inlet temperature Tin to the heat exchanger 13 is equal to the detection temperature T of the tapping temperature thermistor 25 installed in the hot water supply pipe 17a. Therefore, this detection temperature T can be estimated as the acquisition temperature Tin as it is. However, in practice, the detection temperature T may be different from the actual water acquisition temperature Tin due to re-hot water.

Therefore, in the apparatus of the present invention, the inlet temperature Tin for feedforward control does not become the detection temperature T as it is, but is based on the detection temperature T of the tapping temperature thermistor 25 or the variation thereof as follows. Estimated and computed.

To this end, the control device 30 is provided with a function unit, such as the tapping temperature fluctuation detecting unit 34, the intake temperature calculating unit 35, the memory 36 and the like.

The tapping temperature fluctuation detecting unit 34 is a function unit for detecting whether or not the detection temperature T detected by the tapping temperature thermistor 25 is changed when the start of hot water supply is detected by the flow sensor 19.

As described above, the case where the tapping temperature T out fluctuates can be considered to be the case of re-melting. Therefore, it is detected whether there is a change in the temperature of the detection temperature T accompanying the change in the tapping temperature T out, and when there is a change in the temperature, the inlet temperature calculating part 35 detects the tapping temperature thermistor 25. The estimation of the acquisition temperature Tin by the temperature T is not performed.

The acquisition temperature calculating unit 35 obtains the acquisition temperature Tin based on the detection temperature T of the tapping temperature thermistor 25 only when the temperature change amount of the detection temperature T is not detected by the tapping temperature variation detection unit 34. The estimated contents are stored in place of the storage temperature T mem which is already stored in the memory 36 at the same time.

The water acquisition temperature calculating unit 35 compares the detection temperature T of the tapping temperature thermistor 35 with the storage temperature T mem already stored in the memory 36, and stores the memory ( Calculate a new acquisition temperature (Tin) to be stored in 36).

When the detection temperature T ≤ the storage temperature T mem, that is, when the detection temperature T is lower than the storage temperature T mem, the detection temperature T is regarded as a new acquisition temperature Tin, and The detection temperature T is stored in the memory 36.

On the contrary, when the detection temperature T> the storage temperature T mem, that is, when the detection temperature T is higher than the storage temperature T mem, the temperature of the detection temperature T is determined by the storage temperature T mem. A part of the information is inserted to estimate the new acquisition temperature Tin, and stored as the storage temperature T mem.

At this time, the new memory temperature T mem is

Tin = (a × T mem + b × T) / (a + b)... … … … … … … … … … … … … … … … (One)

According to the relational expression, it becomes a new acquisition temperature Tin calculated by a part of the temperature information of the existing storage temperature T mem and a part of the temperature information of the detection temperature T.

That is, at the time t [n], when the detection temperature is (T [n]), the estimated acquisition temperature is (Tin [n]), and the storage temperature is (T mem),

Tin [n] = T mem (n-1) + C. {T [n] -Tin [n]} / d

The relation of is established. That is, a part of the temperature difference between the detection temperature T at the time t [n] and the storage temperature T mem is added to the storage temperature T mem at the time t [n-1] to be added. The acquisition temperature Tin is obtained.

The newly obtained acquisition temperature Tin is stored in the memory 36.

The temperature control controller 31 controls the FF until the detection temperature T of the tapping temperature thermistor 25 rises to a predetermined temperature Ta (eg, Ta = T set-2) lower than the target temperature T set. Through the feed forward control by 32, the heating amount Q is determined based on the target temperature T set, the quantity W, and the storage temperature T mem stored as the inlet temperature Tin, and tapping is performed. After the detection temperature T of the temperature thermistor 25 has risen to the predetermined temperature Ta, the target temperature T set, the detection temperature T and the quantity W are controlled by feedback control by the FB control unit 33. The amount of heating Q is determined based on

The drive unit 37 drives and controls the blower 12 and the governing proportional valve 23 based on the heating amount Q of the temperature regulating control unit 31. The driving unit 37 drives the blower 12 by applying a voltage to the blower 12 based on the heating amount Q by the temperature control controller 31, and based on the detected rotation speed of the blower 12. The energization control of the current value delivered to the governing proportional valve 23 is performed.

In addition, the controller 30 restricts the passage flow rate by adjusting the opening degree of the electric water flow controller 18 based on the detection temperature of the tapping temperature thermistor 25 so that the water supply amount does not exceed the heating capacity.

In addition, the controller 40 that allows the user to arbitrarily set the target temperature (T set) is installed according to the option of the hot water heater. When the controller 40 is installed, the target temperature (T set) is adjusted according to the user's operation. When the controller 40 is not set, a predetermined temperature (for example, 60 ° C.) becomes a target temperature T set.

Next, the temperature control in the gas-fired hot water heater 1 of the present embodiment configured as described above will be described with reference to FIG. 1 centering on the estimation of the inlet temperature Tin.

When a user opens the hot water supply tank (not shown) installed downstream of the hot water supply pipe 17a, water flows through the water supply pipe 17, and flows into the heat exchanger 13. As shown in FIG. At this time, a pulse corresponding to the amount of inflow water is generated by the flow rate sensor 19, and when the quantity W of the operating quantity of the gas-fired hot water heater 1 is detected by the pulse and the start of the hot water is detected (step ( YES in 1)), the ignition control is performed in accordance with a predetermined procedure to start combustion. Further, whether or not the detection temperature T of the tapping temperature thermistor 15 changes is detected (step 2).

When there is no change in the detection temperature t of the tapping temperature thermistor 25 (YES in step 2), the detection temperature T is compared with the storage temperature T mem stored in the memory 36 ( Step 3).

If the detection temperature T is less than or equal to the storage temperature T mem (YES in step 3), the detection temperature T is estimated as the acquisition temperature Tin (step 4), and the detection temperature T is stored in memory. The memory temperature is stored at 36 to replace the storage temperature T mem (step 5).

On the contrary, when the detection temperature T is higher than the storage temperature T mem (NO in step 3), Tin = (a x T mem + b x T) / (a + b)... (1) inputs a part of the temperature information of the detection temperature T into the storage temperature T mem and estimates it as a new acquisition temperature Tin (step 6). The storage temperature T mem in 36) is replaced (step 5).

When the ignition of the burner group 11 is detected by the flame rod 15, the storage temperature T mem of the memory 36, which is estimated and replaced in accordance with steps 4 and 5, respectively, is taken as the acquisition temperature Tin. Feedforward control is performed.

If there is a variation in the detection temperature T of the tapping temperature thermistor 25 (No in step 2), the estimation of the acquisition temperature Tin is not performed and the estimation operation of the acquisition temperature Tin is finished.

Therefore, when ignition of the burner group 11 is detected by the flame rod 15, the temperature control part 31 is based on the memory temperature T mem which is already stored in the memory 36, and the memory temperature T mem. The feedforward control is performed to obtain an acquisition temperature Tin.

In the temperature control by the temperature control controller 31, the target temperature T set and the memory by the controller 40 until the detection temperature T of the tapping temperature thermistor 25 reaches the predetermined temperature Ta. A feedforward control is performed in which the heating amount Q is determined based on the storage temperature T mem at 36 and the quantity W by the flow rate sensor 19, and the detection temperature T is determined as a result of the heating. After reaching the temperature Ta, feedback control is performed in which the heating amount Q is determined based on the target temperature T set and the detection temperature T. FIG.

When the hot water supply is closed and the hot water supply is stopped, combustion is stopped.

If it stops and supplies hot water again after a short time, combustion will start again.

Immediately after such refueling, the water in the heat exchanger 13 is heated by the heat generated by the combustion of the burner group 11 and the combustor case 10, so that the detection temperature T of the tapping temperature thermistor 25 is changed to the heat exchanger. As the detection temperature T fluctuates (No at step 2), the temperature rises and fluctuates with respect to the actual water temperature flowing into (13). The heating amount is determined based on the stored memory temperature T mem of the memory 36, and the heating amount is not determined based on the wrong information from the tapping temperature thermistor 25. Quantity can be determined.

In addition, the temperature of the water supplied to the hot water supply is gradually changed with the change of the season, in the present invention, in consideration of the situation that the hot water heater is used repeatedly daily, during the process of lowering the water temperature transition from summer to winter, the detection temperature (T) as it is In order to avoid the confusion with the case of refueling when the temperature is set to the inlet temperature (Tin) and conversely, the part of the temperature information of the detection temperature (T) is added. It can be replaced by a temperature that gradually rises as the season changes. Therefore, in performing the feedforward control, proper acquisition temperature information is always provided. Therefore, excellent temperature control can be performed.

In the present embodiment, a control apparatus that performs both feed forward control and feedback control is illustrated. However, the same control can be performed in a control apparatus that performs only feed forward control.

In this embodiment, although the flow rate sensor for detecting the quantity of water is provided, the method of detecting the start of hot water supply by the water flow switch without installing the flow rate sensor and calculating the quantity of water from the amount of heating or the like is irrelevant.

In this embodiment, a burner using gas as a fuel is used, but other fuel such as petroleum may be used. In addition, the heat source is not limited to the burner alone, and may be a hot water heater by other heating means such as electric heating.

Claims (2)

The temperature sensor 25 provided at the outlet of the heat exchanger 13, the water flow detecting means 19 for detecting water passing through the heat exchanger 13, and the water flow detecting means 19 start the hot water supply. Intake temperature estimating means 35 for estimating the intake temperature to the heat exchanger 13 on the basis of the detection temperature of the temperature sensor 25 at the time of detection, and estimated by the intake temperature estimating means 35. A hot water heater, comprising: an estimated temperature storing means (36) for storing an estimated temperature, and controlling a heating amount of heating means for heating the heat exchanger (13) based on a stored temperature stored in the estimated temperature storing means (36). In the temperature control apparatus of the above, the water temperature estimating means 35 obtains the water only when the temperature detected by the temperature sensor 25 does not change when the water flow detecting means 19 detects the start of hot water supply. The temperature of the estimated temperature storage means 36 Temperature control device of the hot water heater, characterized in that for replacing the storage temperature. The temperature sensor 25 provided at the outlet of the heat exchanger 13, the water flow detecting means 19 for detecting water passing through the heat exchanger 13, and the water flow detecting means 19 start the hot water supply. Intake temperature estimating means 35 for estimating the intake temperature to the heat exchanger 13 based on the detection temperature of the temperature sensor 25 at the time of detection, and estimated by the intake temperature estimating means 35. A hot water heater, comprising: an estimated temperature storing means (36) for storing an estimated temperature, and controlling a heating amount of heating means for heating the heat exchanger (13) based on a stored temperature stored in the estimated temperature storing means (36). In the temperature control apparatus of the above, the acquisition temperature estimating means (35) estimates the detection temperature as the acquisition temperature when the detection temperature is lower than the storage temperature, and when the detection temperature is higher than the storage temperature. Detection temperature and the storage temperature And a temperature obtained by adding a part of the temperature difference to the storage temperature as the intake temperature.

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