JPH10300213A - Combustor for hot water supply unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To supply hot water of set temperature by eliminating after boiling in a heat-exchanger for hot water supply. SOLUTION: A second flow control means GM2 is provided in a water supply control bypath 18 and a first flow control means GM1 is provided in a hot water supply path 3 on the upstream side of a joint to the bypath 18. When after boiling water flows out from a heat-exchanger 1 for hot water supply, valve opening of the first and second flow control means CM1 , GM2 is controlled to shift the ratio between the flow rate of hot water passing through the first flow control means CM1 and the bypass flow of the second flow control means CM2 in the direction for eliminating the after boiling. After boiling is eliminated by mixing the after boiling water with the water from the bypath 18 and the water flowing into the heat-exchanger 1 for hot water supply during the mixing operation is heated by a burner only with the feedforward heat quantity thus supplying hot water of set temperature stably. Upon finishing the mixing operation, switching is made to combustion control of burner combining the feedforward heat quantity and the feedback heat quantity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot water supply combustion apparatus for heating flowing water passing through a hot water supply heat exchanger by burner combustion and supplying hot water produced by the heating to a desired hot water supply location.

[0002]

2. Description of the Related Art FIG. 23 shows a schematic configuration of a hot water supply combustion apparatus which was previously produced by the applicant. In FIG. 1, a hot water supply passage 2 is connected to an inlet of the hot water supply heat exchanger 1, and a hot water supply passage 3 is connected to an outlet of the hot water supply heat exchanger 1. The hot water supply heat exchanger 1 is provided between the water supply passage 2 and the hot water supply passage 3.
Is provided, and a bypass valve 4 is provided in the bypass passage 4 to open and close the passage.
In the water supply passage 2, a flow rate sensor FS for detecting a flow rate of water supply is provided.
And a feedwater temperature sensor 6 for detecting the feedwater temperature. A heat exchange side temperature sensor 7 is provided on the exit side of the hot water supply heat exchanger 1. Further, a hot water supply temperature sensor 8 is provided at a position slightly downstream of the connection between the bypass passage 4 and the hot water supply passage 3.

The hot water supply heat exchanger 1 is heated by the flame of a burner 10, and a gas passage 11 is connected to the burner 10, and a solenoid valve 12 for opening and closing the passage is connected to the gas passage 11. , 13 and a proportional valve 14 for controlling the amount of gas supplied to the burner 10 by the amount of valve opening.

[0004] The operation of the hot water supply combustion device is performed by a control device 15, and a remote control 9 is connected to the control device 15 by a signal.

[0005] The remote controller 9 is provided with a power switch, an operation switch, a temperature setting device for setting a set temperature of hot water supply, a display section for displaying various information such as a set temperature of hot water supply, and the like.

The control device 15 is provided with a hot water tap (not shown) provided on the hot water supply outlet side of the external pipe connected to the hot water supply passage 3.
Is opened and when the flow rate sensor FS detects a flow rate equal to or higher than the operating flow rate, the combustion fan (not shown) is rotated to supply combustion air to the burner 10 and the solenoid valves 12 and 13 are turned on.
Then, the proportional valve 14 is opened and the ignition means (not shown) is driven to perform the point ignition of the burner 10 so that the hot water temperature detected by the hot water temperature sensor 8 becomes the hot water set temperature set by the remote controller 9. The amount of heat of combustion of the burner 10 is controlled. By this combustion control, flowing water entering the hot water supply heat exchanger 1 from the water supply passage 2 is heated when passing through the hot water supply heat exchanger 1 to become hot water, and this hot water is guided to a desired hot water supply place through the hot water supply passage 3. When the use of hot water is finished and the hot-water tap is closed, a flow-off signal is output from the flow rate sensor FS, and in response to this signal, the control device 15 shuts off the gas passage 11 and stops the combustion of the burner 10, Prepare for the next hot water use.

[0007]

In this type of hot water supply combustion apparatus, after the stoppage of hot water supply combustion, the amount of heat retained in the hot water supply heat exchanger 1 propagates to the retained hot water in the hot water supply heat exchanger 1. When the hot water temperature of the hot water supply heat exchanger 1 increases, a boiling phenomenon occurs, and when the hot water supply combustion is restarted within a short time after the stop of the hot water supply combustion, the hot water supply set temperature in the hot water supply heat exchanger 1 There is a problem that hot water of an overshoot having a higher temperature than the hot water flows out, which makes the user of the hot water uncomfortable.

In order to solve such a problem, when the hot water temperature detected by the heat exchange side temperature sensor 7 is higher than a predetermined reference temperature, the solenoid valve 5 of the bypass passage 4 is opened to exchange hot water supply heat. It is conceivable to mix the hot water from the water heater 1 and the water flowing through the bypass passage 4 to lower the temperature of the hot water from the hot water supply heat exchanger 1 and supply the hot water.

However, the flow rate of the water supplied from the bypass passage 4 per unit time with respect to the overshoot hot water flowing out of the hot water supply heat exchanger 1 is substantially constant regardless of the magnitude of the overshoot. When the amount of overshoot is small, an excessive amount of water is filled, which causes a problem that hot water of an undershoot which is considerably thinner than the set hot water supply temperature occurs, and a case where the amount of overshoot is large. The problem is that a sufficient amount of water cannot be supplied from the bypass passage 4 side to eliminate the overshoot, and the amount of water to be filled is insufficient, and hot water of an overshoot considerably higher than the set hot water supply temperature is supplied. Therefore, there is a problem that hot water close to the hot water supply set temperature cannot be stably supplied at the time of re-watering.

In particular, as shown by a chain line in FIG. 23, a reheating heat exchanger 16 for reheating a bath is formed integrally with the hot water supply heat exchanger 1, and the reheating heat exchanger 1 and the reheating heat are combined. In the case of a single-can, two-channel hot water supply / burning device in which the exchanger 16 is burned and heated by the common burner 10, when the reheating alone operation is performed, the burner 10 causes the retained hot water supply heat exchanger 1 to operate. When the hot water supply operation is started in such a state, the hot water just before the boiling will be discharged from the hot water supply heat exchanger 1, At this time, even if the electromagnetic valve 5 is opened to supply water from the bypass passage 4, the amount of water is insufficient, and a problem arises in that considerably high hot water is supplied through the hot water supply passage 3.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a post-boiler after use of hot water supply, and a heat exchange of hot water supply by independent operation of reheating in a one-can, two-channel type hot water combustion apparatus. The present invention provides a hot water supply combustion apparatus capable of effectively eliminating the post-boiling at the start of hot water supply and supplying a stable hot water temperature substantially at a set hot water supply temperature even when hot water supply starts even if hot water is generated in the water heater 1. is there.

[0012]

In order to achieve the above object, the present invention takes the following measures. That is,
The present invention relates to a hot water supply heat exchanger that heats water supplied from a water supply passage by a combustion flame of a burner to produce hot water and sends the hot water to the hot water supply passage, and the hot water supply heat exchange between the water supply passage and the hot water supply passage. A water supply control bypass passage that bypasses the vessel and communicates with the water supply control bypass passage; and a first flow control unit that controls a flow rate on a hot water side where water flowing out from the water supply control bypass passage joins;
A second controlling the flow rate of the water through the water supply control bypass passage;
Flow rate control means, post-boil detection means for detecting the post-boil temperature of the hot water in the hot water supply heat exchanger when the hot water combustion is stopped, and state in which the post-boil temperature of the hot water in the hot water supply heat exchanger is detected by the post-boil detection means When the hot water supply is started, the valve openings of the first flow control means and the second flow control means are controlled to determine the flow rate of the hot water side and the flow rate of the bypass control flow passing through the water supply control bypass passage. A hot water supply combustion device provided with a mixing control unit that controls a ratio in a direction of eliminating post-boiling, wherein the feeder raises the burner combustion heat amount from the hot water side flow rate to a preset hot water supply set temperature from the hot water supply temperature. A flow ratio combustion control unit for controlling to a forward calorie; a feed forward calorie for increasing a burner calorific value from a total temperature supplied from a water supply temperature to a preset hot water supply temperature. A total flow rate combustion control unit for controlling a hot water supply temperature to a heat amount obtained by adding a feedback heat amount for correcting the hot water supply set temperature; and a combustion control by the flow rate ratio combustion control unit when a mixing operation is performed by the mixing control unit at the start of hot water supply. And a combustion control mode switching unit for performing combustion control by switching from the flow rate ratio combustion control unit to the total flow rate combustion control unit when the mixing operation by the mixing control unit is completed. Is a means to solve.

According to a second aspect of the present invention, there is provided a hot water supply heat exchanger for heating water supplied from a water supply passage by a combustion flame of a burner to produce hot water and sending the hot water to the hot water supply passage, and between the water supply passage and the hot water supply passage. A water supply control bypass passage which bypasses the hot water supply heat exchanger and communicates therewith; first flow control means for controlling a flow rate on a hot water side where water flowing out from the water supply control bypass passage joins; A second flow control means for controlling a flow rate of water flowing through the bypass passage; and a hot water supply combustion device having a post-boiling detection function of detecting post-boiling of the hot water supply heat exchanger when the hot water supply combustion stops. When hot water supply is started from a state in which after-boiler is detected in the exchanger, the first
A mixing mode operation section for controlling a valve opening degree of the flow rate control means and the second flow rate control means to control a flow ratio between the hot water flow rate and the flow rate of the water supply control bypass passage in the direction of eliminating post-boiling. A steady operation mode operation section for operating the valve openings of the first flow control means and the second flow control means to a predetermined steady position; and a predetermined mixing end condition during the mixing mode operation. And a mode switching control unit for designating the steady-state operation mode operation unit to shift the valve opening of the first flow control unit and the second flow control unit from the mixing operation state to the steady operation state when the condition is satisfied. The above configuration is a means for solving the above problem.

In the present invention having the above-described structure, for example, when the hot water supply is started from a state where the post-boiling occurs in the hot water supply heat exchanger, the mixing control section includes the first flow control means and the second flow control means. Is controlled according to the magnitude of the post-boiling of the hot water supply heat exchanger, and the flow ratio between the hot water side flow rate and the bypass control flow rate is controlled in the post-boiling eliminating direction. During this mixing operation, burner combustion is performed only by the feedforward heat amount by the flow ratio combustion control unit.

At the start of hot water supply, the water newly entering the hot water supply heat exchanger is heated by the feedforward heat quantity to hot water having a temperature almost equal to the set temperature of hot water supply. Since the operation is controlled to almost the hot water supply temperature, the hot water at the hot water supply temperature can be stably supplied regardless of the magnitude of the post-boiler temperature.

When the mixing operation by the mixing control section is completed, the combustion control mode switching section switches from the flow rate combustion control section to the total flow rate combustion control section to perform combustion control. As described above, since the hot water supply temperature is accurately controlled to the hot water supply set temperature, there is almost no change in the hot water supply temperature when switching to the combustion control by the total flow rate combustion control unit, and the switching of the combustion control is performed smoothly.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 4 shows a model example of a hot water supply combustion apparatus according to the present invention by a schematic configuration. The hot water supply combustion device of the present invention is not only a single-function hot water supply device (water supply device having only a hot water supply function), but also a two-can, two-channel type hot water supply combustion device (a hot water supply heat exchanger and a reheating heat exchanger are provided separately and independently, A combined bath and hot water supply system, in which each heat exchanger is heated and burned by a separate burner, and a one-can, two-channel hot water combustion device (a hot water supply heat exchanger and a reheating heat exchanger are integrated) It is also applied to a combined bath and hot water supply type in which the integrated hot water supply heat exchanger and the reheating heat exchanger are heated and burned by a common burner.

In FIG. 4A, a water supply passage 2 is connected to an inlet side of the hot water supply heat exchanger 1, and a hot water supply passage 3 is connected to an outlet side of the hot water supply heat exchanger 1. Water supply passage 2
A continuous bypass passage 17 that bypasses the hot water supply heat exchanger 1 is connected between the hot water supply passage 3 and the hot water supply passage 3. One end (inlet side) of the water supply control bypass passage 18 is connected to the position, and the hot water supply passage 3
The other end side (outlet side) of the water supply control bypass passage 18 is communicatively connected to a position D downstream of a connection portion C with the constant bypass passage 17.

A first flow rate control means GM variably controls the flow rate of hot water which is a mixture of hot water exiting the hot water supply heat exchanger 1 and water which always passes through the bypass passage 17 between the CDs in the hot water supply passage 3.
₁ is provided, also, the water supply control bypass passage 18, the second flow control means GM ₂ is provided with variable control of the flow rate with the possible closure function. These first flow control means GM ₁ second flow rate control means GM ₂ is intended to be constituted by water control means for controlling the valve opening degree, for example, by a gear motor, the first flow control means GM ₁ second The second flow rate control means GM ₂ is provided with a valve opening detection sensor (not shown) such as a Hall IC for detecting a fully open position and a fully closed position of the valve.

Between the AB of the water supply passage 2, the combined flow rate of the hot water of the hot water supply heat exchanger 1 and the water constantly flowing out of the bypass passage 17 is determined by the hot water side flow Q passing through the first flow control means GM _1.
The first flow sensor FS ₁ to be detected is provided as, also, the water supply passage 2 in the hot water supply passage 3 downstream position than the connecting portion D of the outlet side of the water supply control bypass passage 18
The second flow sensor FS ₂ is provided for detecting the total flow (total flow rate) Q _T to incoming water to. A water supply temperature sensor 6 for detecting a water supply temperature is provided in the water supply passage 2, and a heat exchange side temperature sensor 7 for detecting a temperature of hot water discharged from the hot water supply heat exchanger 1 is provided on an output side of the hot water supply heat exchanger 1. A heat exchange auxiliary temperature sensor 22 for detecting the temperature of the hot water in the heat exchange at an intermediate position (for example, an intermediate portion) of the water pipe passage of the hot water supply heat exchanger 1 as necessary.
Is provided. In the hot water supply passage 3, a mixed hot water temperature (mixing hot water temperature) of the hot water discharged from the first flow rate control means GM ₁ and the water discharged from the water supply control bypass passage 18 is supplied to the hot water supply temperature T.
A hot water supply temperature sensor 8 that detects a _MIX is provided.

When the hot water supply combustion device is configured as a combined hot water supply device for bath and hot water supply, the water supply control bypass passage 18 is used.
The hot water supply passage 3 is branched from the hot water supply passage 3 on the downstream side of the merging position D, and the hot water supply water is dropped into the bathtub 25 via the reheating circulation circuit 24 on the bath side.

When a hot water supply combustion device is constructed as such a combined bath and hot water supply device, a reheating heat exchanger 16 provided in a reheating heating circulation path 24 is formed independently of the hot water supply heat exchanger 1. Then, the hot water supply heat exchanger 1 and the reheating heat exchanger 16 are configured to be heated by combustion with separate and independent burners, so that a two-can, two-channel water heater is provided. Also, as shown in FIG. As shown, the hot water supply heat exchanger 1 and the reheating heat exchanger 16 are integrally formed, and the integrated hot water supply and the reheating heat exchangers 1 and 16 are configured to be burned and heated by a common burner. A single water canal type water heater is formed. In FIG. 4A, reference numeral 26 denotes a circulation pump for circulating hot water in the bathtub 25 through the additional heating circulation path 24 to perform additional heating. The pouring solenoid valve opens the passage 23.

The model example of the hot water supply combustion device shown in FIG. 4B is a second flow rate sensor FS ₂ shown in FIG.
Are omitted, and the other configuration is the same as the model example shown in FIG.

The model of the hot water supply combustion apparatus shown in FIG. 4C is of a type in which the configuration of the apparatus is further simplified, and is provided in the model examples of FIGS. 4A and 4B. heat交出side temperature sensor 7, the heat exchanger auxiliary temperature sensor 22, the first omitted and a flow rate sensor FS _1, the total feed water flow rate feedwater control the second flow sensor FS ₂ for detecting a (total hot water flow rate) Water supply passage 2 upstream of the connection portion B of the water bypass passage 18
The other configurations are the same as those of the model examples in FIGS. 4A and 4B. The operation of the device of the model example shown in FIG. 4 is controlled by a control device 15, and a remote control 9 is connected to the control device 15 in the same manner as the device shown in FIG.
Heating is performed by the burner 10, and in each of the model examples shown in FIG. 4, the burner 10 controls the gas supply amount to the burner 10 by the opening amount of the proportional valve 14 in the same manner as that shown in FIG. Although ten combustion system mechanisms are provided, they are not shown in FIG. 4 and these combustion system mechanisms will be described using the reference numerals given in FIG.

In the hot water supply combustion apparatus of this embodiment, when the hot water supply operation is started in a state where the post-boiling overshoot water is generated in the hot water supply heat exchanger 1, the burner 10 of the hot water supply heat exchanger 1 is turned off. perform combustion heating only by feedforward heat, hot water side through the flow Q _BP and first flow control means GM ₁ water exiting the feedwater control bypass passage 18 to eliminate the boiling hot water after leaving the hot-water supply heat exchanger 1 The flow rate is controlled by the flow rate control with respect to the flow rate Q. FIG. 5 is a block diagram of a first control configuration for performing the flow rate control. This first control configuration includes an input temperature detection unit 28
And a target flow ratio calculator 30 as a target flow ratio detector
And a detected flow ratio calculating unit 31 as a detected flow ratio detecting unit
, A bypass control flow detection unit 32 and a hot water side flow detection unit 3
3 and a mixing control unit 34.

The first control configuration shown in FIG.
(A) and (b), the input temperature detection unit 28 takes in the hot water temperature T _OUT on the outlet side of the hot water supply heat exchanger 1 detected by the heat exchange side temperature sensor 7, first directly or indirectly the flow rate control means GM ₁ enters water side temperature (temperature of the hot water and water exiting the water and always bypass passage 17 leaving the hot-water supply heat exchanger 1 are mixed) as the input temperature T _K To detect. When the input temperature T _K is directly detected, as shown in FIGS.
The temperature sensor 19 for detecting the input temperature may be provided in the hot water supply passage 3 between the outlet side C of the fuel cell 7 and the inlet of the _first flow rate control means GM1 for detection, but the number of parts of the temperature sensor 19 is reduced. In order to reduce the equipment cost, the input temperature T _K
Is detected indirectly.

The indirect detection of the input temperature is obtained by taking in the outlet temperature T _OUT of the hot water supply heat exchanger 1 detected by the heat exchange side temperature sensor 7 of the hot water supply heat exchanger 1 and performing the following calculation. .

That is, in the input temperature detecting section 28, the amount of the water supplied through the water supply passage 2 always flows to the hot water supply heat exchanger 1 at the connection point A of the bypass passage 17 and always flows to the bypass passage 17. The distribution ratio with the quantity is given in advance. For example, when the distribution ratio on the hot water supply heat exchanger 1 side is m and the distribution ratio on the continuous bypass passage 17 side is n, the input temperature detection unit 28 determines the input temperature T by the following equation (1) given in advance. _{Find K} by calculation.

T _K = T _OUT × m + T _IN × n (1)

In the equation (1), for example, the distribution rate on the hot water supply heat exchanger 1 side is 70%, and the distribution rate on the bypass passage side is always 3%.
At 0%, 0.7 is given as the value of m, and 0.3 is given as the value of n. This input temperature detector 2
The information on the input temperature T _K obtained in step 8 is added to the target flow ratio calculating section 30. The input temperature T _K is the value of the hot water supply heat exchanger 1
Since the temperature varies depending on the temperature of the hot water in the hot water supply, the input temperature T _K can be used to detect the post-boiling in the hot-water supply heat exchanger 1. It has.

By the way, the boil after the hot water supply heat exchanger 1, release heat to heat the flow rate Q of having a high temperature input temperature T _K than the hot water supply set point temperature T _SP falls to the hot water supply set point temperature T _SP is The flow rate Q _BP passing through the water supply control bypass passage 18 is equal to the heat absorption heat required to increase from the water supply temperature T _IN to the hot water supply set temperature T _SP . From this thermal equilibrium balance relationship,
The following equation (2) is derived.

Q _BP / Q = (T _K −T _SP ) / (T _SP −T _IN ) (2)

In the equation (2), the flow rate Q on the hot water side at the input temperature T _K and the bypass control flow rate at the feed water temperature T _IN (the feed water flow rate passing through the feed water control bypass passage 18) are mixed, and the hot water set temperature T _SP Is the balance equation of the calorie balance for achieving the temperature of, and Q _BP / Q on the left side represents the flow rate ratio between the bypass control flow rate Q _BP and the hot water side flow rate Q. In addition, the hot water supply set temperature T _SP and the water supply temperature T _{IN on} the right side of the equation (2) can be regarded as constant values, and the value on the right side is an input temperature that changes depending on the after-boiling temperature in the hot water supply heat exchanger 1. It changes depending on the value of T _K.

That is, by adjusting the flow ratio on the left side to match the value on the right side of equation (2), which depends on the input temperature T _K that changes depending on the post-boiler temperature of the hot water supply heat exchanger 1, the flow rate Q and the bypass control flow Q temperatures are mixed and _BP should be equal to the hot water set temperature T _SP.

In this embodiment, attention is paid to this point, and (2)
The right side of the equation is defined as a target flow rate ratio W _ST between the bypass control flow rate Q _BP and the hot water side flow rate Q, and the left side of the equation (2) is defined as a detected flow rate ratio W _DE .

W _ST = (T _K −T _SP ) / (T _SP −T _IN ) (3)

W _DE = Q _BP / Q (4)

The target flow ratio calculation unit 30 is given in advance the calculation expression of the target flow ratio W _ST of the above equation (3) as solution data, and the target flow ratio calculation unit 30
An input temperature T _K obtained from 8, in accordance with the water supply and information of the feed water temperature T _IN obtained from the temperature sensor 6, captures information of the hot water supply set point temperature T _SP given by remote control, the equation (3), the target flow rate ratio W _{The ST} is obtained by calculation, and the calculated value is added to the mixing control unit 34.

The hot water flow rate detection unit 33 detects the hot water flow rate Q passing through the first flow rate control means GM ₁ by taking in the sensor output of the first flow rate sensor FS ₁ and calculates the detected flow rate ratio. Add to part 31. If necessary, the detected value of the hot water side flow rate Q is added to the bypass flow rate control detection unit 32.

In the case of the model shown in FIG. 4 (a), the bypass control flow detecting section 32
_The bypass control flow rate Q _BP is obtained by subtracting Q detected by the _first flow rate sensor FS ₁ from the total flow rate (total flow rate) Q _T detected in ₂ .

Q _BP = Q _T -Q (5)

When the hot water supply combustion device is the model shown in FIG. 4B, the bypass control flow rate detection unit 32 obtains the bypass control flow rate Q _BP according to the solution data. This solution data is given by the following equation (6).
The bypass control flow rate detection unit 32 includes an input temperature T _K applied from the input temperature detection unit 28, a hot water supply temperature T _MIX detected by the hot water supply temperature sensor 8, a water supply temperature T _IN detected by the water supply temperature sensor 6, and the hot water side. The data of the hot water side flow rate Q detected by the flow rate detection section 33 is taken in, the bypass control flow rate Q _BP is calculated by the above equation (6), and the calculation result is added to the detected flow rate calculation section 31.

Q _BP = (T _K −T _IN ) · Q / (T _MIX −T _IN ) (6)

The detected flow ratio calculating section 31 fetches the data of the hot water flow rate Q obtained by the hot water flow rate detecting section 33 and the bypass control flow rate Q _BP obtained by the bypass control flow detecting section 32, and the above (4) In accordance with the equation, a detected flow ratio W _DE between the bypass control flow rate Q _BP and the hot water side flow rate Q is obtained by calculation, and the calculation result is added to the mixing control unit 34.

The mixing control section 34 sets the target flow ratio W
Comparing the _ST and the detected flow rate ratio W _DE, detecting the flow rate ratio W _DE first flow control means GM ₁ and second flow control means GM ₂ the flow rate increase or decrease direction of each other in a direction that matches the target flow rate ratio W _ST The flow rate control is performed so that is in the opposite direction. More specifically, the difference between the target flow ratio W _ST and the detected flow ratio W _DE is determined, and K ₁ , K ₂
As the coefficient (gain), the first flow control means GM ₁ applies the voltages V ₁ obtained by the equation _{V 1 = K 1 (W SP} -W DE), the second flow control means GM ₂ Is V ₂ = K
₂ a voltage V ₂ which is obtained by calculation of (W _SP -W _DE) applying the flow rate control. That is, the target flow rate ratio W _SP and the detected flow rate ratio W _DE and differential voltage of the first flow control means GM ₁ and second addition to the flow control means GM ₂ respectively corresponding to the hot water side flow rate Q and the bypass control flow The flow rates of Q _BP and Q are controlled such that the flow rate of Q _BP increases and decreases in the opposite direction.

More specifically, for example, when the after-boiling in the hot water supply heat exchanger 1 is large, that is, when the input temperature T _K is high, the value of the target flow ratio W _ST is large as is apparent from the above equation (3). In order to increase the detected flow ratio W _DE in order to match the target flow ratio W _ST , that is, to increase Q _BP in the direction as shown in the equation (4).
The Q in the small direction, i.e., the first flow control means GM ₁ in the closing direction, the second control means GM ₂ is controlled in the opening direction.

Then, as the temperature of the post-boiled water in the hot water supply heat exchanger 1 decreases, the temperature of the input temperature T _K decreases.
The target flow ratio W _ST gradually decreases, and accordingly, in order to match the target flow ratio W _ST , the bypass flow control is performed in a direction in which the detected flow ratio gradually decreases, that is, as is apparent from the equation (4). The direction in which the flow rate Q _BP is reduced, the direction in which the hot-water-side flow rate Q is increased, that is, the first flow control means GM ₁ is controlled in the opening direction, and the second flow control means GM ₂ is controlled in the closing direction. It is.

[0048] Figure 6 is boiling post this by mixing control unit 34 first flow control means GM ₁ and second flow control means GM ₂ of the valve opening degree of the state of the hot water supply heat exchanger 1 side of the heat交出Inlet temperature ( have the meanings indicated in high and low relationship between the temperature), as is apparent from this figure, the voltages V ₁ applied to the first flow control means GM ₁ second voltage V ₂ applied to the flow control means GM ₂ is The increasing / decreasing directions are opposite to each other, and the valve opening of the second flow control means gradually increases as the temperature of the post-boiler in the hot water supply heat exchanger 1 increases. flow rate valve opening control means GM ₁ has been shown to be reduced gradually controlled.

FIG. 7 shows a state in which a post-boiling temperature is generated in the hot-water supply heat exchanger 1, and when the hot-water supply operation is started, the post-boiling temperature T _OUT , the hot water supply temperature T _MIX, and the flow control means GM ₁ , GM _Two
When the hot water supply operation is started, the post-boiled water in the hot water supply heat exchanger 1 is discharged, the temperature gradually increases, and after reaching the peak P, the post-boil temperature gradually increases. Lower. At this time, the first flow control means GM ₁ is tapping temperature of boiling rear is controlled in the closing direction toward the peak,
The second flow control means GM ₂ is controlled in the opening direction, the hot water side flow rate Q is reduced, the bypass control flow rate Q _BP is increased, and the after-boiling is eliminated. In the direction of gradually increasing the flow rate Q on the hot water side,
The bypass control flow rate Q _BP is controlled in a gradually decreasing direction, so that the hot water temperature of the hot water supply temperature T _MIX close to the hot water supply set temperature T _SP is stably supplied without being substantially affected by the change of the after-boiler temperature.

FIG. 8 is a flowchart showing the operation of eliminating post-boiling at the start of hot water supply operation in this embodiment.
When the hot water supply operation is started, the target flow ratio _WST is obtained by calculation in step 101, and then the detected flow ratio _WDE is calculated in step 102.

Next, at step 103, a difference between the target flow ratio W _ST and the detected flow ratio W _DE is determined, and whether the difference is positive or negative is detected. When the detected flow rate ratio is larger than the target flow rate ratio, the first flow control means GM ₁ at step 104 in the opening direction, controlling the second flow control means GM ₂ in the closing direction. Conversely, when the detected flow ratio W _DE is smaller than the target flow ratio W _ST , the first flow control means GM ₁ is controlled to close in step 105 and the second flow control means GM ₂ is controlled to open in step 105. I do.
Then, whether it is the cancellation condition which mixing operation of the rear boiling eliminate hot water side flow rate Q and the bypass control flow Q _BP are given in advance in step 106 it is determined, if not reach the release condition, i.e., boiling rear When the hot water is still remaining in the hot water supply heat exchanger 1, the operation after step 101 is repeated, and when the condition for canceling the mixing operation is satisfied, that is, the post-boiled hot water in the hot water supply heat exchanger 1 when it has finished out almost completely closes the second flow control means GM _2, and proceeds to the total flow rate control from the flow ratio control at the start hot water supply, the proportional control by the total amount of heat obtained by adding the feedforward quantity of heat and the feedback amount of heat The combustion operation is controlled by the combustion control operation of the steady operation based on the operation.

In this total water amount control, as described above, the second flow rate control means GM ₂ is maintained in the closed state, so that the hot water side flow rate Q detected by the _first flow rate sensor FS ₁ is equal to the total flow rate Q _T. Equal (Q _T = Q), feed forward heat P _{F / F}
Is the theoretical amount of heat required for the flow rate Q to be heated from the feed water temperature T _IN to the hot water supply set temperature T _SP , and P _{F / F} = Q (T _SP −T
_IN ) or considering the thermal efficiency η, P _{F / F}
= Q (T _SP −T _IN ) / η, and the feedback heat amount PF _{/ B} is the difference between the hot water supply temperature T _MIX detected by the hot water supply temperature sensor 8 and the hot water supply set temperature T _SP . Is the amount of heat required to eliminate (cancel) P P _{/ B} = Q · K (T _SP −T _MIX ) (where K is a coefficient (gain)) or by taking thermal efficiency η into account.
_{F / B} = Q · K (T _SP −T _MIX ) / η

A detailed description of the conditions for canceling the mixing operation for eliminating post-boil will be described later.

According to the first control configuration of the flow rate control, when the hot water supply operation for eliminating the post-boiled hot water in the hot water supply heat exchanger 1 is started, the supply water temperature of the supply water flow rate Q is set to the hot water supply set temperature T.
Since heat the hot water supply heat exchanger 1 only by the feedforward quantity of heat to increase in the _SP, the enter new from the water supply passage 2 to the hot-water supply heat exchanger 1 water becomes to be heated in hot water of the hot water supply set point temperature T _SP, also hot water The temperature of the post-boiled water generated in the heat exchanger 1 is detected by the heat exchange side temperature sensor 7 as soon as it exits the hot water supply heat exchanger ₁ and the input temperature to enter the first flow control means GM1. T _K is detected, and Yugawa flow rate Q and the bypass control flow Q _BP in a direction corresponding to the target flow rate ratio W _ST with hot water side flow rate Q and the bypass control flow Q _BP for the input temperature is hot water set temperature since the detection flow ratio W _DE of is controlled, irrespective of the boil after the hot water supply heat exchanger 1 temperature, the mixing ratio of hot water so that the flow rate Q of the hot water side is the hot water supply set point temperature T _SP is Controlled to eliminate the effects of post-boiling in the hot water supply heat exchanger 1 , The hot water close to the hot water set temperature can provide the revolutionary effect that can be stably hot water.

Further, in the flow ratio control, the first
Because of the flow control means GM ₁ and second flow control means GM ₂ increasing and decreasing directions of flow are controlled in the opposite direction, it is assumed that the response of the flow rate ratio variable is extremely excellent, the change in the rear boiling hot water temperature The flow ratio control that quickly follows can be achieved, and thereby the control accuracy of the hot water temperature stabilization at the time of hot water supply of the post-boiled hot water is remarkably improved, and the reliable hot water temperature stabilization control becomes possible. In particular, in the case of a one-can-two-water-path type hot water supply combustion device, for example, when the reheating of the bath is performed alone, the hot water in the hot water supply heat exchanger 1 stays in the burner. In the extreme case, the heating of 10 causes heating to a high temperature just before boiling, but also in this case, when the hot water supply operation is started, the flow ratio control with the quick response is performed, and down first flow control means GM _first valve through the hot water of the Is, by the second flow rate control means GM ₂ is controlled to the fully open direction, even if tapping is high temperature hot water boiling verge from the hot water supply heat exchanger 1, and the hot water of the hot water supply set temperature by the flow rate ratio control hot water Therefore, it is possible to exhibit excellent performance in terms of safety.

Further, in the present embodiment, during the mixing operation for eliminating the boiling water temperature after flowing out of the hot water supply heat exchanger 1, the feedforward heat quantity with respect to the hot water side flow rate Q (the flow rate Q is changed from the feed water temperature T _IN to the set hot water supply temperature). T _SP required to increase the is to provide a theoretical heat), a feed-forward heat for this flow rate Q is feed water feed-forward heat (total flow rate Q _T temperature to the total flow rate Q _T T
Theoretical amount of heat required to increase the hot water supply set point temperature T _SP from _IN)
Is smaller than becomes a heat shortage less than the required amount of heat to the total flow rate Q _T to the hot water set temperature after the rear boiling hot water has finished out of the hot water supply heat exchanger 1, Therefore, the second flow rate control means As a result of the operation of the GM ₂ in the closing direction to close the water supply control bypass passage 18, when the temperature of the post-boiled water in the hot water supply heat exchanger 1 is eliminated, the flow is quickly shifted from the flow ratio control by mixing to the total flow control. can do.

Moreover, when the second flow rate control means GM ₂ is closed, the hot water side flow rate Q coincides with the total flow rate Q _T , so that the feed forward heat quantity with respect to the flow rate Q and the feed forward heat quantity with respect to the total flow rate Q _T are different. Equal,
Almost no change of the feed-forward amount of heat when the second flow control means GM ₂ is switched from the open to the closed, thereby, the total flow rate control steady operation from the flow rate ratio control by mixing without variation of the hot water supply temperature occurs It is possible to make the transition smoothly while keeping the temperature of the hot water stable.

[0058] In contrast, when given a feed-forward heat to the total flow rate Q _T during mixing operation of the rear boiling eliminated, because the amount of heat is large to give, finished out hot water boil rear from the hot water supply heat exchanger 1 also, the second flow control means GM ₂ is not in the closing direction of the operation, there is a problem that can not be quickly transition from the flow ratio control to the total flow rate control, also,
When the flow rate through the hot water supply heat exchanger 1 is small, this small flow rate is heated by a large amount of feedforward heat, causing a problem such as a danger of boiling. However, in the present embodiment, the mixing is performed during the mixing operation as described above. Flow Q
Since the combustion heating is performed by the feedforward heat amount (with a smaller heat amount), the occurrence of the above-described problem can be effectively solved.

FIG. 9 shows a second control configuration of the flow ratio control in this embodiment. In the second control configuration, when the hot water at the input temperature T _K is mixed with the bypass control flow rate Q _BP , the mixing temperature is changed to the hot water side flow rate Q _BP.
Is calculated as the detected temperature T _MIX by the information of the total flow rate Q _T and the flow rate ratio between the hot water flow rate Q and the bypass control flow rate Q _{BP in} a direction in which the detected hot water supply temperature T _MIX matches the hot water supply set temperature T _SP. The input temperature detector 2
8, a hot water temperature calculating unit 35 as a hot water temperature detecting unit,
And a mixing control unit 34.

The input temperature detector 28 has the same configuration as the input temperature detector of the first control configuration shown in FIG. 5, and detects the input temperature T _K directly or indirectly.
The detected value is added to the hot water supply temperature calculator 35.

The hot water supply temperature calculating section 35 is provided with the following equation (7) as solution data. This arithmetic expression is also obtained by the relation of the calorific balance.

T _MIX = ｛(T _K −T _IN ) ・ Q / Q _T ｝ + T _IN (7)

The hot water supply temperature calculating section 35 has an input temperature T _K applied from the input temperature detecting section 28, a water supply temperature T _IN detected by the water supply temperature sensor 6, and a hot water side detected by the _first flow rate sensor FS1. and the flow rate Q, captures the data of the total flow rate Q _T detected by the second flow sensor FS _2, (7)
The hot water supply temperature T _MIX is calculated according to the equation, and the obtained hot water supply temperature T _MIX is supplied to the mixing control unit 34.

The mixing control section 34 sets the hot water supply set temperature T _SP applied from a remote controller or the like as a target temperature, and sets the first hot flow control means GM _{1 in} a direction in which the calculated hot water supply temperature T _MIX coincides with the target temperature T _SP. And the second flow control means GM ₂
Are controlled so that the directions of increase and decrease of the flow rates are opposite to each other.

More specifically, the difference between the set hot water supply temperature T _SP and the calculated hot water supply temperature T _MIX is obtained, and the first flow rate control means GM ₁ obtains V ₁ = K ₁ d (T _SP −T applying a voltages V ₁ which is obtained by calculation of the _MIX), also the voltage V ₂ which is obtained by calculation of V ₂ = K ₂ e (T _SP -T _MIX) is applied to the second flow control means GM _2, the The first flow control means GM ₁ and the second flow control means GM ₁
To control the opening and closing direction opposite to each other flow control means GM ₂ of. K ₁ and K ₂ are coefficients (gains) obtained in advance through experiments and the like.

Also in the case of the second control configuration, similarly to the first control configuration, during the mixing operation for eliminating the post-boiled hot water temperature in the hot water supply heat exchanger 1, the feed water is supplied to the hot water supply heat exchanger 1. This is performed by giving only the forward heat amount P _{F / F.}

When the after-boiler temperature in the hot water supply heat exchanger 1 is high, that is, when the input temperature T _K is high, the first flow rate control means GM ₁ moves in the closing direction by the mixing control section 34 to the second direction. flow control means GM ₂ are controlled respectively in the opening direction, as the temperature of boiling rear is reduced, the first flow control means GM ₁ in the opening direction, the second flow rate control means GM ₂
Are controlled in the closing direction, respectively, to eliminate post-boiling. Thus, the first flow control means GM ₁ and the increase or decrease direction of the second flow control means GM ₂ flow together opposite to the direction that matches the hot water detected temperature T _MIX hot water supply set point temperature T _SP of the target temperature The flow ratio between the hot water side flow rate Q and the bypass control flow rate Q _BP is controlled so as to achieve high accuracy and high reliability as in the case of the first control configuration shown in FIG. Hot water and water mixing control for eliminating post-boiling is achieved,
It is possible to provide an effect that hot water having a set hot water supply temperature can be supplied irrespective of the after-boil temperature.

FIG. 10 shows a third control configuration of the flow ratio control in this embodiment. This control configuration
Be of simplified structure corresponding to the model example shown in (c) of FIG. 4, the hot water temperature sensor 8 which functions as a rear boiling detection means actually measured hot water temperature T _MIX, the actual hot-water supply temperature T _MIX and compared with the hot water supply set point temperature T _SP set by a remote controller or the like at the mixing control unit 34, a first flow control means GM ₁ in a direction to match the actual hot-water supply temperature T _MIX in hot water of the target temperature set point temperature T _SP and controls the second flow control means GM ₂ in the direction of increasing or decreasing direction of flow are opposite to each other. The control operation of the mixing control unit 34 in the third control configuration is the same as the operation of the mixing control unit 34 shown in FIG. This third control configuration is different from the second control configuration shown in FIG. 9 in that the hot water supply temperature T _MIX is measured without being calculated, and other than that, the operation is the same as that of the second control configuration.

This third control configuration is based on the measured hot water supply temperature T
_MIX and hot water supply set temperature T _SP
The flow control means GM ₁ is intended to perform a second control of the flow control means GM _2, wherein the second control arrangement of the input temperature detector 28 and the first and the flow sensor FS _1, heat交出side temperature Since the sensor 7 can be omitted, the device configuration can be simplified. Thus, despite the simplified apparatus configuration, the measured hot-water supply temperature T Yugawa the _MIX in a direction that matches the hot water supply set point temperature T _SP, which is the target temperature flow rate Q and the bypass control flow Q
The flow ratio control of _BP since the first flow rate control means GM ₁ and increasing or decreasing direction of the second flow control means GM ₂ flow performed by controlling so that the opposite, boiling hot water supply heat exchanger 1 even the high-temperature water in the verge is caused by boiling the rear, that first flow control means GM ₁ is in the closing direction (squeezing direction), the second flow control means GM ₂ is controlled to the fully open direction, water By mixing the side flow rate Q and the bypass control flow rate Q _BP , hot water having a temperature substantially equal to the hot water supply set temperature T _SP can be produced, and the hot water can be stably supplied. The advantage is that an inexpensive hot water supply combustion apparatus having high performance and high accuracy in stabilizing the hot water temperature can be obtained.

FIG. 11 shows still another example of the model to which the flow ratio control of this embodiment is applied (the illustration of the reheating heat exchanger 16 is omitted in this example of the model). In the hot water supply combustion device shown in (1), the flow rate sensor FS _BP for directly detecting the bypass control flow rate is provided directly in the water supply control bypass passage 18, so that the flow rate sensor FS _BP directly detects the bypass control flow rate Q _BP ,
The second flow sensor F hot water side flow rate Q is to detect the total flow rate Q _T
A flow ratio control operation by the first and second control configurations is obtained by calculating by subtracting the bypass control flow rate Q _BP detected by the flow rate sensor FS _BP from the detected flow rate Q _{T of} S _2. is there.

In each control structure of the flow ratio control,
Although the constant bypass passage 17 bypassing the hot water supply heat exchanger 1 is provided, the constant bypass passage 17 may be omitted. In this case, the input temperature T _K of the flow rate Q entering the first flow rate control means GM ₁ coincides with the detected temperature T _OUT of the heat exchange side temperature sensor 7, so that the value of T _OUT is used instead of T _K. By performing the arithmetic processing using the above, the control operations of the first and second control configurations can be similarly performed.

Further, in the examples of the hot water supply and combustion devices of the respective models described above, one continuous bypass passage 17 is provided, but a plurality of continuous bypass passages 17 may be provided.

In the present embodiment, in order to effectively perform the hot water temperature stabilization control by the flow ratio control of the post-boiled hot water temperature, the hot water supply operation is started from the state before the start of the hot water supply operation and the steady operation state is started. Are divided into four operation modes,
The first flow control means GM at each of the classification mode positions
₁ and second to define the operating state of the flow control means GM _2, the operating state of the hot-water supply operation has a configuration for switching the operation mode for each to clear the previously given conditions.

[0074] FIG. 12 shows the operation mode of the flow control means GM ₁ and GM ₂ and a block diagram of the switching control, the mode switching control section 36, and resolution standby mode operation unit 37 boiling rear, the steady operation mode operation It has a unit 38, a mixing mode operation unit 40, and an operation off mode operation unit 41.

In this embodiment, the flow rate control means GM ₁ ,
The operation modes of the GM ₂ are classified into four modes: a post-boiling eliminating standby mode of mode 1, a steady operation mode of mode 2, a mixing mode of mode 3, and an operation off mode of mode 4. The operation in mode 1 is performed by the post-boiling elimination standby mode operation unit 37, the operation in mode 2 is performed by the steady operation mode operation unit 38, the operation in mode 3 is performed by the mixing mode operation unit 40, and the operation in mode 4 Are performed by the operation-off mode operation unit 41, respectively.

The mode 1 is a flow control means G before hot water supply combustion in the state where hot water is generated in the hot water supply heat exchanger 1.
M ₁ and GM ₂ are the operations. In the operation of mode 1, after the hot water supply operation is started, the hot water from the hot water supply heat exchanger 1 is immediately removed from the bypass passages 17 and 18 to the hot water. To prepare for the supply of water, for example,
The ratio of hot-water supply heat exchanger side flow rate Q _H and the bypasses 17 side flow rate Q _W is Q _H: Q _W = 30: with 70 to become such a valve opening degree is so as to stand, the hot water supply heat exchanger Even if the maximum peak post-boiler water temperature that can occur within 1 is generated, the system waits at a predetermined valve opening that can be filled with hot water at the hot water supply set temperature.

The operation in the mode 1 is performed under the operating conditions of the hot water supply combustion device in which it is determined that hot water is generated in the hot water supply heat exchanger 1. In the example, the following five conditions are given. The first condition is that, in the case of a combined canister with one can and two water channels, the hot water supply is stopped in a state of simultaneous reheating of the bath and the hot water supply, and in this case, the hot water supply is stopped. Since the reheating combustion is continued, the retained hot water in the hot water supply heat exchanger 1 is heated by the reburning burner combustion to be in a post-boiling state, so that the mode 1 operation is performed.

The second condition is a case where the reheating of the bath is started in a state where the hot water supply is stopped in the case of the combined water heater of one can and two water channels. Also at this time, the water staying in the hot-water supply heat exchanger 1 is heated by the reheating combustion and is brought into a post-boiling state, so that the mode 1 operation is performed.

The third condition is that when the operation switch is turned on, the heat exchange side temperature sensor 7 and the heat exchange auxiliary temperature sensor 22
At least one of the temperatures is equal to or higher than the temperature determined as the after-boiling temperature (for example, 50 ° C.). The fourth condition is
In the previous hot water supply combustion operation, the hot water side flow rate Q and the bypass control flow rate Q _BP are operated in a mixing control state by the flow rate ratio control for eliminating the post-boiled hot water temperature, and the total flow rate Q _T and the hot water flow rate are controlled. This is when the hot water supply is stopped before the difference from the side flow rate Q reaches the predetermined mixing end determination flow rate. 5
The third condition is given in advance when the previous hot water supply operation is in a state where the hot water side flow rate Q and the bypass control flow rate Q _BP are mixed by the flow rate control for eliminating boiling after the above-described hot water supply and hot water is supplied. When the hot water supply is stopped before reaching the mixing allowable time.

When the hot water supply is performed by mixing the hot water side flow rate Q and the bypass control flow rate Q _BP passing through the water supply control bypass passage 18 by the flow ratio control for eliminating the post-boiling, as the post-boiling temperature decreases, First flow control means G
Valve opening degree of the M ₁ is controlled in the direction of increase, the second valve opening of the flow control means GM ₂ is controlled in a direction gradually decreases, the second flow rate control means GM _second valve is closed Before the mixing state is stabilized, the second flow control means GM
A phenomenon in which the hot water supply operation is continued to the end with the _second valve open may occur.

When such a phenomenon occurs, the required combustion heat quantity becomes a predetermined maximum combustion heat quantity (the opening degree of the proportional valve is maximum) from the flow rate control in which the stabilization of the tapping water temperature is given top priority. You can not change to the adjusting to take total flow controls the first valve opening of the flow control means GM ₁ in the opening direction, and that it becomes impossible to exhibit the maximum capability of the water heater combustion device occurs Become.

When the valve of the second flow control means GM ₂ is kept open, the flow rate of water flowing through the hot water supply heat exchanger 1 is reduced by the amount of water flowing through the water supply control bypass passage 18. The temperature of the hot water in the exchanger 1 may be in a boiling state, which is very dangerous. Further, when the hot water supply heat exchanger 1 has a function of stopping the hot water supply combustion when the hot water temperature in the hot water supply heat exchanger 1 becomes a boiling state, when the inside of the hot water supply heat exchanger 1 becomes a boiling state as described above. In addition, there arises a problem that the hot water supply combustion is stopped by activating the above function and the hot water supply operation is interrupted. In this embodiment, in order to prevent these problems,
As the mixing progresses, when the flow rate difference between the total flow rate Q _T and the hot water side flow rate Q reaches the mixing end determination flow rate (for example, 0.5 liter / min), the second time immediately or after a given spare time has elapsed, the second It has a flow rate control means GM ₂ so as to force the closure.

[0083] Further, in the present embodiment, it is given as a pre-mixing time allowed time ranges performing mixing, and forcibly close the second flow control means GM ₂ when the expiration of the mixing time allowed. Before the difference between the mixing total flow rate Q _T and the hot water side flow rate Q reaches the mixing end determination flow rate and before the mixing allowable time has elapsed, it is assumed that the post-boiled water is still generated in the hot water supply heat exchanger 1. Therefore, when hot water supply is stopped in such a situation, the first flow rate control means GM ₁ and the second flow rate control means GM ₁ prepare for re-heating of the post-boiled hot water generated in the hot water supply heat exchanger 1. control means GM ₂ in the state of the valve opening degree of the mode 1 and is to wait for the next hot water supply operation. When any one of the above five conditions is satisfied, the flow control means GM ₁ and GM ₂ enter the operation state for mode 1.

[0084] Mode 2 is an operation in which the second flow control means GM ₂ becomes a closed state. The first case in which the operation of mode 2 is performed is a steady operation of hot water supply. In the second case in which the operation of mode 2 is performed, the temperature T _OUT on the outlet side of the hot water supply heat exchanger 1 detected by the heat exchange side temperature sensor 7 during standby before the start of the hot water supply operation and the heat exchange assistance. Both the heat exchange temperature T _Z1 detected by the temperature sensor 22 and the post-boiling determination temperature (for example, 50
° C). At this time, even if the hot water supply is started, it is determined that there is almost no effect of the after-heating, and in this case, the hot water supply in the cold start state (a long time has elapsed after the hot water supply was stopped, and the hot water supply heat exchanger 1 cools down). state treated similarly to state) hot-water supply operation is started in the provided in the hot water supply operation in a state of closing the second flow control means GM _2.

In the case of a one-can-two-water channel type combined water heater, the heat exchange side temperature sensor 7 and the heat exchange auxiliary temperature sensor 2
2, when one or both of the detected temperatures is lower than the post-boiling determination temperature, when the hot water supply is operated alone, when the hot water supply is stopped, and after the bath reheating operation, the post pump (recirculation of the bath after the reheating) The operation of mode 2 is performed after the operation of the pump is continuously driven and the hot water in the bathtub is circulated through the reheating circuit 24 without burning the burner, for example, after one minute has elapsed. This is because, in the one-can-two-water channel type combined water heater, even after the hot water supply is independently burned and then stopped, the heat from the hot water supply heat exchanger 1 is radiated to the water pipe on the bath side. Therefore, the effect of the post-boiling in the hot water supply heat exchanger 1 is small, and when, for example, one minute has elapsed after the operation of the post pump after the bath was heated, the hot water supply heat exchanger 1 heated by the reheating of the bath was used. The post-boil heat inside is released to the bath-side circulating flow circulated by the post pump, reducing the effect of the post-boil.
The operation of the mode 2, and prepare for the next hot water burned in closed and the second flow controlling means GM _2. Of course, when one or both of the hot water temperature detected by the heat exchange side temperature sensor 7 and the heat exchange auxiliary temperature sensor 22 becomes lower than the post-boiling determination temperature before the set time has elapsed since the start of the post pump. , Mode 2 may be adopted.

In the present embodiment, during the operation in mode 2, the second flow control means GM ₂ is in the closed state, the flow rate Q _H passing through the hot water supply heat exchanger 1 and passing through the bypass passage 17. flow rate Q _W ratio between the 70:30 (Q _H: Q _W =
70:30).

[0087] Mode 3 is an operation for controlling by mixing the bypass control flow Q _BP through the flow Q a water supply control bypass passage 18 of the hot water side by the flow ratio control to eliminate the boiling was described above, this mode The operation 3 is an operation to be performed by starting the hot water supply operation in the standby state after the boiling in the mode 1.

Mode 4 is an operation performed when the operation is turned off in each of the modes 1 to 3 above. In this mode 4, the first flow control means GM ₁ and the second flow control an operation to both the reference position of the valve means GM _2,
In this embodiment, the fully open position is set as the reference position,
It is fully open position when a operating condition of the first flow control means GM ₁ and second flow control means GM ₂ the mode 4.

The mode switching control unit 36 includes a bath-on signal (boil-on signal), a bath-off signal (bake-off signal), a hot-water supply signal, a hot-water supply signal, an operation-on signal,
Run-off signal, running water on signal (on signal of running water detection applied from flow sensor or running water switch, etc.), running water off signal, boiling signal (bath boiling signal), pushing operation end signal described later, T _OUT , T _Z1, Q, and the signal is applied, such as Q _T, the mode switching control unit 36 against the various types of information in advance the input and operating conditions for each mode given in the internal memory, the operation mode Switch control.

FIG. 13 shows the flow of switching the mode operation.
Briefly, based on the above, first, in the operation off state, all the operations are in the mode 4 and the first flow control means G
M ₁ and second flow control means GM ₂ is set to the fully open position the valve opening is the reference position. When the operation ON signal is input in the mode 4 state, the detection information of the heat exchange side temperature sensor 7 and the heat exchange auxiliary temperature sensor 22 is taken in, and the detected temperatures of these sensors 7 and 22 are equal to or higher than the post-boiling judgment temperature. When at least one of T _OUT and T _Z1 is equal to or higher than the post-boiling judgment temperature, it is judged that post-boiling hot water exists in the hot water supply heat exchanger 1, and the operation from the mode 4 to the operation of the mode 1 is performed. The flow control means G is switched by switching the valve opening to eliminate the post-boiling.
M ₁ and GM ₂ are put on standby. When both T _OUT and T _Z1 are lower than the after-boiling judgment temperature, the operation is switched from the mode 4 to the mode 2 and the second flow control means GM ₂
In the fully closed state to prepare for the start of hot water supply.

When the hot water supply is started in the operation state of the mode 1 and the running water is detected to be on, the operation mode is switched from the mode 1 to the mode 3 and the hot water side flow rate Q and the water supply control bypass are controlled by the flow rate ratio control described above. Mixing control with the bypass control flow rate Q _BP passing through the passage 18 is performed, and the valve opening of the flow rate control means GM ₁ , GM ₂ is controlled so as to eliminate post-boiling.

When the hot water supply is stopped during the mixing operation in mode 3 and the running water is turned off, it is determined that the post-boiled water is still present in the hot water supply heat exchanger 1, and
The operation is switched from mode 3 to mode 1 to prepare for the next hot water supply. When the difference between the total water flow Q _T and the hot water flow rate Q becomes equal to or less than the mixing end determination flow rate due to the progress of the mixing operation in mode 3 and the mixing operation ends, the operation mode is switched from mode 3 to mode 2. , the second flow control means GM ₂ shifts to the steady operation of the total flow control from to the flow ratio control in the fully closed state to continue the hot water supply operation.

The operation in mode 2 includes two operations, that is, an operation during a hot water supply operation in a steady state and a standby operation in a cold start state before the start of hot water supply. When the reheating of the bath is started in the hot water supply standby state, or when the reheating of the bath is being performed simultaneously with the steady operation of the hot water supply, the hot water supply operation is stopped and the reheating of the bath continues. In this case, reheating is performed in the hot water supply stopped state, so that after-heating in the hot water supply heat exchanger 1 occurs. In this case, the operation mode is switched from mode 2 to mode 1 to start the next hot water supply. Be provided. In any of the modes 1 to 3, when the operation-off signal is input, the operation shifts to the operation of the mode 4, and the flow control means GM ₁ and GM ₂ set the valve opening to the fully open position. .

As described above, in this embodiment, when the operation switch is turned off, the first flow control means GM ₁ is always used.
When the second valve opening of the flow control means GM ₂ is set to the valve opening degree of the reference position, is shifted to the operation of each mode 1-3 from this set state, the control valve opening to suit each mode of operation With this configuration, the control position of the valve opening does not shift with time, and the control of the valve opening can be performed reliably and accurately.

[0095] Figure 14 shows the structure of a second closing control of the flow rate control means GM ₂ at the end of the mixing operation of the mode 3, the flow rate comparison section 42 and the GM ₂ controller 4
3 and a data memory 44. During the mixing operation by the flow ratio control in the mode 3, the flow rate comparing section 42 always takes in the total flow rate Q _T and the hot water side flow rate Q and compares them to obtain a difference Q _T −Q = ΔQ.
Add Q data to GM ₂ controller 43. GM ₂ control unit 4
3 compares the mixing end determination flow rate (for example, 0.5 liter / min) stored in advance in the data memory 44 with the flow rate difference ΔQ obtained by the flow rate comparison unit 42,
When the flow rate difference ΔQ becomes equal to or less than the mixing end determination flow rate, it is determined that the post-boiled water in the hot water supply heat exchanger 1 has almost completely exited. In this case, the second flow rate control means GM
_{To 2} operating state is remains open to prevent from being stabilized, GM ₂ control unit 43 closes the second flow control means GM _2.

[0096] Further, the data in the memory 44 are stored in the value of the mixing time allowed, for example, 50 seconds to allow the operation of the mixing, GM ₂ controller 43, the mixing operation mode 3 exceeds the mixing allowable time when the can is closed and the second flow controlling means GM ₂ as well.

The mixing permissible time is given with some allowance for the time when the post-boil is completed in consideration of the internal volume of the hot water supply heat exchanger 1 and the like, and the mixing operation is not completed within this mixing permissible time. It is estimated that some malfunction is occurring in, and boiling due after the second flow control means GM ₂ inside the hot water supply heat exchanger 1 be closed is eliminated when the mixing permissible time has elapsed Therefore, there is no problem. For this reason, in the present embodiment, when the mixing operation is not completed within the allowable mixing time, the mixing operation is forcibly ended when the allowable mixing time has elapsed, and the flow rate ratio control is performed. It shifts to control.

As described above, in this embodiment, the mode 3
And when the difference between the hot water side flow rate Q is below the mixing end determination flow configuration with respect to the total flow rate Q _T during operation of conditions as when the operating time of the mode 3 has reached the mixing time allowed for setting the mixing This is given as a mixing end condition for terminating.

Next, a more improved control structure for terminating the mode 3 mixing operation will be described. Improved configuration of the first stage may store a value of the mixing termination prohibition time (e.g. 8 seconds) in the data memory 44, GM ₂ controller 4
3, the total flow rate Q _T and hot water side flow rate ΔQ of the difference between the flow rate Q without immediately closing the second flow control means GM ₂ even when the mixing end judgment flow rate determined by the flow rate comparison unit 42, the when ΔQ is standing by in a status of not second closure of the flow control means GM ₂ to further mixing completion prohibition time elapses from the time of equal to or less than a mixing completion judgment flow, it elapses the mixing terminated prohibition time 2
In which of a structure to perform the closure of the flow control means GM _2.

By providing the mixing end prohibition time as described above, the following effects can be obtained. That is, when the flow rate of the hot water supplied by the hot water supply combustion device is small, when the hot water supply is started in a state where the post-boiling occurs in the hot water supply heat exchanger 1, as shown in FIG. The time from when the boiling water first comes out of the vessel 1 first starts to flow until the heat-exchange-side temperature sensor 7 detects the peak boiling temperature thereafter becomes longer, and the boiling water starts to flow out of the hot water supply heat exchanger 1. When the post-boil temperature is detected by the heat exchange side temperature sensor 7 at the start of hot water supply, since the post-boil temperature is relatively low, and the low post-boil temperature is output for a relatively long time. The first flow control means is controlled in the closing direction, and the second flow control means is controlled in the opening direction.

However, since it takes a long time until the temperature of the post-boil peak comes out from the hot water supply heat exchanger 1, the mixing of the hot water side flow Q and the bypass control flow Q _BP due to the first hot water of the post-boil comes out. the difference may become less mixing completion judgment flow, in such a case, immediately second flow control means GM ₂ the closed state of the total flow rate Q _T and hot water side flow rate Q before the peak of the boiling rear exits by If this is done, hot water having a hot water temperature of the post-boiler peak will come out later, and there is a possibility that a problem that the mixing operation of the hot water of the post-boiler peak cannot be performed thereafter may occur, but the mixing end prohibition time is provided. Accordingly, even when the flow rate difference ΔQ is equal to or smaller than the mixing end determination flow, the second flow rate control means GM ₂ becomes possible to continue the state of the mixing operation mode 3 without being closed, its The peak of the boiling post within the post mixing completion prohibition time has hot water from the hot water supply heat exchanger 1,
Correspondingly, the mixing operation by the flow ratio control for filling the post-boil is performed, so that the problem that the mixing of the hot water at the peak of the post-boil cannot be eliminated can be solved.

An improved configuration of the second stage of the mixing termination control according to the present embodiment is provided with a prohibition time variable setting section 46 as shown by a dashed line in FIG. The end prohibition time is variably set.

That is, the prohibition time variable setting section 46 includes:
For example, the relationship data between the flow rate and the mixing end prohibition time, which increases the mixing end prohibition time as the flow rate decreases as shown in FIG. 16, is given in advance. the to water flow rate, in this embodiment takes in detection data of the total flow rate Q _T,
Set the mixing termination prohibition time corresponding to the detected flow rate, and configured to apply the set value to GM ₂ controller 43.

Thus, the GM ₂ control section 43 controls the second flow control means GM ₂ to perform the closing operation by using the mixing end prohibition time set by the prohibition time variable setting section 46.

In the improved configuration of the second stage, the mixing end prohibition time is automatically set according to the flow rate, so that a long useless mixing end prohibition time is given despite the large flow rate. of or problem that delay unnecessarily the closure timing of the flow rate control means GM _2, the flow control means to prevent the problem that is closed before the peak of the boiling rear by mixing finished prohibition time is too short exits At the optimal timing at which the post-boiling peak ends and the post-boiling is eliminated.
The flow control means GM ₂ of the first embodiment is closed, and the transition from the mixing operation of the flow ratio control by the feedforward heat quantity to the steady operation control of the total flow rate by the combined use of the feedforward and the feedback can be performed at the optimal timing. Will be obtained.

FIG. 17 and FIG. 18 show that the flow rate difference Δ
This shows a configuration for indirectly closing the _second flow control means GM2 instead of directly closing it when Q does not become equal to or less than the mixing end determination flow rate. This second
Construction of flow indirect closing of the control means GM ₂ is intended to be configured with a feed-forward heat variably setting unit 47, the feed-forward heat variably setting unit 47 (starting the hot water supply in the subsequent boiling state) mixing starting The elapsed time from the elapsed time exceeds the allowable mixing time, which is detected by receiving a signal from the timer. After the allowable mixing time elapses, the feedforward heat quantity is changed with time as shown by the solid line in FIG. , Is variably set in a stepwise or continuously decreasing direction as shown by a broken line. Then, the data of the variably set feedforward calorie is added to the combustion control unit 48, and the combustion control unit 48
In order to generate the variably set feedforward heat amount, the burner 10 controls the valve opening drive current to the proportional valve 14.
Combustion.

As described above, the feedforward heat amount is variably set in the decreasing direction, so that the hot water supply combustion heat amount is reduced. As a result, the input temperature T _K is reduced, and the first temperature is controlled by the above-described flow ratio control for eliminating post-boiling. the flow control means GM ₁ is the opening direction, the second flow rate control means GM ₂ are results that are controlled in the closing direction, the difference ΔQ between the total flow rate Q _T and hot water side flow rate Q becomes less mixing completion judgment flow, thereby , it becomes the second flow control means GM ₂ is is securely closed, can transition to a steady combustion operation of the water heater.

In this embodiment, the second flow control means GM
_When closing the valve ₂ , the fully closed position of the _second flow control means GM2 is detected by a sensor such as a Hall IC, and then the valve is pushed in the closing direction to further close the valve. ing.

[0109] Figure 19 shows a control structure of this pushing operation, driving the GM ₂ controller 43 duty changing section 49
Is provided. The drive duty changing section 49 is provided in the Hall I
When the fully closed position detection sensor 50 such as C received a second detection signal in the fully closed position of the flow control means GM _2, changes the duty of the voltage for driving the valve in the closing direction to be lower. For example, when the valve is operated from the open position to the closing direction with a drive voltage of 50% duty, when the detection signal of the fully closed position is applied from the fully closed position detection sensor 50, the duty of the drive voltage is set to 50%. %, For example, variably set to 30%.

The GM ₂ control unit 43 changes the duty set by the drive duty changing unit 49 from when the fully closed position of the valve is detected for a fixed time (for example, 5 seconds) measured by a timer, as shown in FIG. As shown, the duty of the drive voltage is lowered, and the valve is further pushed in the closing direction to drive.

By pushing the valve in the closing direction,
The valve of the second flow control means GM ₂ is reliably closed,
It is possible to make a transition to the steady-state operation of hot water supply by total flow control in a state where the flow of the leak in the water supply control bypass passage 18 is completely prevented.

As described above, by reducing the duty of the driving voltage,
That, push in the closing direction, the valve is a valve with a torque which can avoid damage to the gear of the second flow control means GM ₂ burnout and gear motor gear motor coil also reduces the driving power of the valve following impact with the valve seat since to carry out the pushing movement in the closing direction after closure, to prevent burnout of the coil of the flow control means GM ₂ Reduction motor, also to prevent the occurrence of breakage of the gear motor gear. That is, even after the valve is driven in the closing direction to reach the fully closed position, if the pushing drive is performed in the closing direction of the valve with the same high driving power, the large driving power is converted into heat energy, and the high heat energy As a result, the coil of the gear motor may be burned out, or the gear may be damaged because a large torque is applied to the gear of the gear motor. However, as in this embodiment, the drive power is reduced to close the valve. Since the push-in drive in the direction is performed, without causing such a problem,
Reliable closing of the valve is achieved.

In this example, as a means for lowering the power of the pushing drive in the closing direction of the valve, the duty is variably set to a lower value. It is needless to say that the driving power may be reduced by using other means as long as the driving power can be reduced by changing the driving power.

FIG. 21 shows the configuration of control for switching from the operation state of mode 1 to the operation state of mode 2 shown in FIG. In the figure, the mode switching control unit 36 has a temperature comparison unit 51, and this temperature comparison unit 51 exchanges the detected temperature T _OUT of the heat exchange side temperature sensor 7 with the hot water supply heat exchange detected by the heat exchange auxiliary temperature sensor 22. One or both of the detected temperatures T _Z1 of the hot water temperature in the vessel 1 are fetched, and these detected temperatures T _OUT and T _Z1 are compared with a predetermined judgment reference temperature T _TH .

This reference temperature T _TH is determined when the hot water from the hot water supply heat exchanger 1 is mixed with the water passing through the bypass passage 17 and the hot water is discharged from the hot water supply heat exchanger 1 with the _second flow control means GM ₂ closed. This means the post-boiling temperature in the hot water supply heat exchanger 1 at which the hot water temperature just reaches the hot water supply set temperature T _SP , and therefore, as shown in FIG. When the temperature is higher than _TH , when the second flow control means GM ₂ is discharged in a closed state, the hot water supply set temperature T
Become hot water of high overshoot than _SP, conversely, the lower undershoot hot water than hot water supply set point temperature T _SP in case hot water temperature of the hot water supply heat exchanger 1 is less than T _TH. Focusing on this point, in the present embodiment, the temperature comparison unit 51
One or both of _OUT and T _Z1 is compared with a predetermined reference temperature T _TH, and when the detected temperature is lower than the reference temperature T _{TH, the} overshoot water higher than the hot water supply set temperature T _SP. Determines that hot water is not supplied and switches from the operation state of mode 1 to the operation state of mode 2 for preventing overshoot due to post-boiling to prepare for the next hot water supply operation.

Further, in the case of the one-can-two-water-bath type bath / hot water supply combined system, the mode switching control unit 36 outputs a signal indicating that the reheating alone operation has been completed and the operation of the post-pump after boiling has been completed (FIG. When the post-pump end signal is detected, the hot water supplied by the post-pump circulates in the reheating circuit 24 in the fire-extinguishing state of the burner 10 and is heated by the reheating combustion to be in a post-boil state. It is determined that the post-boiling state has been eliminated because the heat in the heat exchanger 1 is absorbed by the circulating bath water, and the mode is switched from the standby state of mode 1 to the standby state of mode 2 in this case as well. Things.

Although the temperature of the hot water in the hot water supply heat exchanger 1 is lower than the reference temperature T _TH , the operation in the mode 1 is performed, that is, the second flow control means GM ₂ is opened. In the state (of course, the first flow control means G
M ₁ is also opened), the hot water supply operation is started, after the hot water low hot-water supply heat exchanger 1 than the determination reference temperature T _TH is mixed with water exiting always bypass passage 17, further water supply There is a problem that hot water considerably lower than the hot water supply set temperature T _SP is supplied because the water is mixed with the water flowing out of the control bypass passage 18. However, as in the present embodiment, the hot water supply heat exchanger 1 side has a problem. because when one or both of the hot water temperature T _OUT and T _Z1 is lower than the determination reference temperature T _TH is switched to the second mode of operation which closes the second flow control means GM _2, the hot water of the undershoot The effect that hot water supply can be avoided is obtained. Further, the switching from the operation state of mode 1 to the operation state of mode 2 is performed in consideration of both the hot water side temperature T _OUT of the hot water supply heat exchanger 1 and the substantially middle temperature T _{Z1 of the} hot water supply heat exchanger 1. By doing so, even if the temperature distribution in the hot water supply heat exchanger 1 fluctuates, the information on the post-boiled hot water temperature in the hot water supply heat exchanger 1 can be detected more reliably, so that the mode operation is switched. Control accuracy can be improved.

FIG. 1 shows a characteristic of this embodiment.
FIG. 13 shows a switching configuration of combustion control from the mixing operation in mode 3 shown in FIG. 13 to the steady hot water supply operation in mode 2 and includes a combustion control mode switching unit 52; A flow ratio combustion control unit 53 for controlling the combustion during the mixing operation and a total flow rate combustion control unit 54 for controlling the combustion in the steady operation in mode 2 are provided. The flow ratio combustion control unit 53 calculates a feedforward heat amount P _{F / F} required to increase the hot water side flow rate Q from the feed water temperature T _IN to the hot water set temperature T _SP , and generates the feed forward heat amount P _{F / F.} The valve opening drive current to the proportional valve 14 is controlled so as to supply the amount of gas to be supplied.

[0119] Also, the total flow rate combustion control unit 54 in a state in which the second flow control means GM ₂ is closed, the total flow rate Q _T (second flow rate control means so GM ₂ is in the closed state a total flow rate Q _T
= Feed forward heat amount P _{F / F} required to increase the hot water side flow rate Q) from the feed water temperature T _IN to the hot water set temperature T _SP , and a feedback heat amount for correcting the deviation of the hot water temperature T _{MIX from} the hot water set temperature T _SP to zero. P _{F / B} is calculated, and a gas amount required to generate a total heat amount obtained by adding the feed forward heat amount P _{F / F} and the feedback heat amount P _{F / B} to the proportional valve 14 is supplied to the burner 10. Controls the valve opening drive current.

By the way, when the post-boiled hot water in the hot water supply heat exchanger 1 is discharged, if the variable control of the amount of gas supplied to the burner 10 is performed according to, for example, the detected hot water supply temperature T _MIX , When the combustion control using both the forward calorie PF _{/ F} and the feedback calorie PF _{/ B} is performed, the temperature of the post-boil is an unstable transient phenomenon that changes with the lapse of time after the start of tapping. Conversely, by performing the variable amount control, there is a problem that the hot water temperature fluctuates, or a new hot water supply heat exchanger is used because the gas amount is reduced to eliminate the post-boiler temperature. There is a possibility that the amount of heating heat of the water entering the inside 1 may be insufficient, and after the temperature of the post-boiled water has finished, there may be a problem that undershoot water having a temperature lower than the set hot water supply temperature may be discharged. Therefore, in the present embodiment, the following combustion control mode switching unit 52
Is provided to avoid the above problem.

The combustion control mode switching unit 52 designates the combustion control by the flow ratio combustion control unit 53 in the mixing operation state by the flow ratio control in mode 3, and causes the flow ratio combustion control unit 53 to perform the combustion control. On the other hand,
The hot water supply combustion operation is switched from the mixing operation in mode 3 to mode 2
When switched to the operation, that is, closing signal of the second flow rate control means GM ₂ valve is applied from the fully closed position detection sensor 50 such as a Hall IC in a state where the signal of the hot-water supply on is detected At this time, it is determined that the state of the mode 3 has been switched to the operation state of the mode 2 (that is, it is determined that the mixing operation by the mixing control unit 34 has been completed). The control is switched to the control for the flow rate combustion control unit 54.

As described above, when the post-boiled water comes out of the hot water supply heat exchanger 1 and the hot water supply temperature T _MIX becomes overshoot water higher than the set hot water supply temperature T _SP , the hot water supply heat exchanger 1 is fed by the feedforward heat quantity. Is heated, and new water entering the hot water supply heat exchanger 1 after the start of hot water supply combustion is heated by the heat of the feedforward heat amount P _{F / F} so that the temperature of the flow rate Q on the hot water side becomes the hot water supply set temperature, The post-boiled water remaining in the hot water supply heat exchanger 1 before the start of hot water supply is set so that the detected flow ratio between the bypass control flow rate Q _BP and the flow rate Q on the hot water side matches the target flow rate ratio, as described above. Flow control means GM ₁ ,
By controlling the opening degree of the valve of the GM ₂ , it is possible to supply hot water having a hot water supply set temperature substantially regardless of the degree of the post-boiler temperature.

Further, the mode of operation from mode 3 to the mode 2 is switched to the combustion control mode from the flow rate combustion control section 53 to the combustion control operation of the total flow rate combustion control section 54. It is possible to stably supply hot water in a combustion control mode capable of sufficiently exhibiting the maximum capacity of the hot water.

FIG. 2 is a time chart showing the relationship among hot water supply temperature T _MIX , total flow rate Q _T , hot water side flow rate Q, and gas amount in a series of control operation states from the flow rate combustion control state to the total flow rate control. It is shown.

As shown in FIG. 2, in the present embodiment, the hot water supply temperature T _MIX is substantially equal to the hot water supply set temperature T _SP by performing the flow ratio control by supplying the feedforward heat quantity in the mixing operation for eliminating the after-boiling. It has been proved that the hot water temperature is close to the stable hot water temperature, and in the operation of mode 2 after the mixing is finished, the hot water supply temperature is accurately controlled to the hot water supply set temperature, and the flow rate ratio control is changed to the total flow rate control. It has been proved that there is no fluctuation in the hot water temperature at the boundary of the switching of, and the flow rate control is smoothly switched to the total flow rate control.

Next, the control operation for switching from the flow rate control to the total flow rate control will be briefly described with reference to the flowchart of FIG. This operation shows a case where hot water is generated in the hot water supply heat exchanger 1 and the hot water supply operation is started in the mode 1 state.

[0127] First, the first on-signal from the flow sensor FS ₁ (running water on signal) is added at step 201 it is determined whether the hot water supply has been started. When it is determined that the hot water supply has been started, in the next step 202, the mixing operation is performed by the flow ratio control of the hot water side flow Q by the flow ratio control and the bypass control flow _QBP . Meanwhile, step 2
In 03, the feedforward heat quantity P _{F / F} is obtained by calculation, and burner combustion is performed only with the feedforward heat quantity.

In step 204, it is determined whether the mixing operation in mode 3 satisfies the termination condition, that is, the difference ΔQ between the total flow rate Q _T and the hot water side flow rate Q becomes equal to or less than the mixing termination determination flow rate, and the mixing termination prohibition time whether but it has elapsed, or if the mixing operation has exceeded the mixing allowed time determination is made, a second closing of the flow control means GM ₂ at the next step 205 when filled with mixing end condition.

In step 206, the second flow control means G
When M ₂ is determined whether or not a fully closed state, the detection signal of the fully closed position from the fully closed position detecting sensor 50 is applied,
Alternatively, when the push-in operation of the valve in the closing direction is further performed, and the end signal of the push-in operation is added, it is determined that the valve is in the fully-closed state, and the operation is shifted from the operation state in mode 3 to the total flow control in mode 2 ( Step 207).

On the other hand, the combustion control unit switches the combustion control mode from the flow rate combustion control to the total flow rate combustion control.
Feedforward calorie P _{F / F} and feedback calorie P
_The heating of the hot water supply heat exchanger 1 is controlled by the total amount of heat with the _{F / B.} In step 209 the first off-signal from the flow sensor FS ₁ determines whether added. When the OFF signal is not applied, the faucet of the hot water tap is not closed, and it is determined that the hot water supply is being used continuously, and the combustion operation is continuously performed by the total flow rate control. First
When the OFF signal from the flow sensor FS ₁ (running water off signal) is applied is closed is the hot-water tap is determined that the use of hot water supply is finished, ready for the next hot water to stop the combustion.

As described above, the operation of the flowchart starts with the hot water supply operation in the operation state of the mode 1 when the post-boiled water is generated in the hot water supply heat exchanger 1 and the flow rate ratio of the mode 3 Mode 2 from mixing operation by control
Of the hot water supply heat exchanger 1
When there is no over-boiled hot water remaining at the overshoot hot water temperature, the operation state of mode 2, that is, the second
The flow control means GM ₂ are waiting on the hot water in a closed state, when the hot-water supply operation is started in this state will make a hot-water supply operation immediately by the total flow rate combustion control.

The present invention is not limited to the above-described embodiment, but can adopt various embodiments. For example, in the above embodiment, solution data for obtaining the target flow rate ratio, the total flow rate, the hot water supply temperature, and the input temperature of the hot water side flow rate entering the first flow rate control means are given by the arithmetic expressions, respectively. The solution data may be given as table data, graph data, or the like.

Further, in the above-described embodiment, the mixing end prohibition time is given as a starting point when the flow rate difference ΔQ between Q _T and Q becomes equal to or less than the mixing end judgment flow rate, but this is set at the start of mixing (at the start of hot water supply). (In this case, the time is longer than the mixing end prohibition time starting from the time when ΔQ becomes equal to or less than the mixing end determination flow rate). In this case as well, as shown in FIG. 13, the time is automatically set in accordance with the flow rate of the water flow. it can.

[0134] Further, in the above embodiment, although fully close the second flow control means GM ₂ at a mixing completion by the mixing control unit 34, to a predetermined valve opening degree not completely closed You may narrow down. In this case, the combustion control mode switching unit 52
When the flow control means GM ₂ is narrowed down to the above-mentioned set valve opening degree, it is determined that the mixing operation by the mixing control section 34 has been completed, and the switching from the flow rate combustion control section 53 to the total flow rate combustion control section 54 is performed. Perform combustion control. Thus, it is possible to switch the total flow combustion control from flow ratio combustion control during the mixing terminated by combustion control mode switching unit 52, the second flow control means GM ₂ after the mixing has been completed is not closed state Also, the maximum capacity of the hot water supply combustion apparatus can be exhibited by the total flow rate combustion control.

[0135]

According to the present invention, when hot water supply is started from a state in which post-boiling occurs in the hot water supply heat exchanger, the mixing control unit controls the flow rate of the hot water from the hot water supply heat exchanger side and the bypass passage for the water supply control. Since the ratio of the flow rate to the flow rate is controlled in the direction of eliminating post-boiling, water is mixed with the post-boiled water, and during this mixing operation, the combustion control of only the feedforward calorie is performed by the flow ratio combustion control unit. The water newly entering the heat exchanger is heated to almost the hot water supply set temperature with a stable amount of feed forward heat, and the hot water flowing out of the hot water supply heat exchanger is subjected to the mixing operation regardless of the degree of post-boiling. It is effectively eliminated, and hot water at a hot water supply set temperature can be supplied stably.

If the combustion control using both the feed forward heat amount and the feedback heat amount during the mixing is performed, that is, if the burner combustion control is performed according to the temperature of the hot water generated by the mixing, the combustion control and the mixing control may interfere with each other. Although the hunting phenomenon that the hot water supply temperature fluctuates unstable occurs, in the present invention, as described above, when the mixing control is performed, the combustion using only the feedforward heat amount which is not affected by the hot water supply temperature is performed. Since the control is performed, the hunting can be prevented, and as described above, an epoch-making effect of being able to stably supply hot water at a hot water supply set temperature regardless of the degree of post-boiling is achieved. be able to.

Further, at the end of mixing, when the combustion control mode switching unit switches from the flow ratio combustion control unit to the total flow combustion control unit to perform combustion control,
Since the hot water supply temperature is accurately controlled to the hot water supply set temperature during mixing as described above, the hot water supply temperature hardly fluctuates due to the switching of the combustion control, and the combustion control can be smoothly switched. Further, as described above, when the mixing is completed, the flow rate combustion control is switched to the total flow rate combustion control. Therefore, after the mixing operation is completed, the hot water supply operation is stabilized by the combustion control capable of sufficiently exerting the maximum capacity of the apparatus. It is possible to perform it.

When the mixing mode operation is completed, the valve opening of the first and second flow control means is shifted from the mixing state to the steady operation state, and when it is determined that the influence of the after-boiling has been eliminated. That is, the valve openings of the first and second flow control units can be shifted to the steady positions at appropriate timings that can prevent hot water temperature fluctuation due to switching of the valve openings of the flow control units. Further, if the hot water supply operation is continuously performed in the mixing operation state, a problem such that the maximum capacity of the apparatus cannot be exhibited occurs. However, as described above, when the mixing is completed, the mixing state is reliably changed from the mixing state to the steady state. Therefore, after the post-boiling is eliminated, it is possible to perform a hot water supply operation that can avoid the above-described problem and exhibit the maximum capacity of the apparatus.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a switching control configuration of a combustion control mode which is characteristic in the embodiment.

FIG. 2 is a time chart showing an example of the relationship between the hot water supply temperature T _MIX , the total flow rate Q _T , the flow rate Q on the hot water side, and the gas amount at the time of transition from flow rate control to total flow rate control.

FIG. 3 is a flowchart of the present embodiment illustrating an operation at the time of transition from flow ratio control to total flow control.

FIG. 4 is an explanatory diagram of various model examples of a hot water supply combustion device to which the present invention is applied.

FIG. 5 is a block diagram of a configuration example of a main control part for performing a flow ratio control of a hot water side flow rate and a bypass control flow rate so that a detected flow rate ratio matches a target flow rate ratio.

FIG. 6 is an explanatory diagram showing a control mode of a valve opening degree of a first flow rate control means and a second flow rate control means in the embodiment.

FIG. 7 is a time chart of the after-boiler temperature, the hot-water supply temperature, and the operation of the flow rate control means GM ₁ and GM ₂ for explaining the flow ratio control operation for eliminating post-boiling in the hot water supply heat exchanger in the embodiment.

FIG. 8 is a flowchart of an example of an operation for performing control for eliminating post-boiling so that the detected flow ratio matches the target flow ratio.

FIG. 9 is a diagram showing a result of calculating a hot water supply temperature in consideration of post-boiling;
FIG. 3 is a block diagram of a control configuration of the present embodiment for performing a flow ratio control so that a hot water supply temperature obtained by this calculation matches a hot water supply set temperature.

FIG. 10 is a block diagram of a control configuration according to the present embodiment in which a hot water supply temperature is directly detected by a hot water supply temperature sensor and a flow ratio control between a hot water side flow rate and a bypass control flow rate is performed in a direction in which the hot water supply temperature matches a set hot water supply temperature. FIG.

FIG. 11 is an explanatory diagram showing another model example of the hot water supply combustion device to which the present invention is applied.

FIG. 12 is a block diagram illustrating various operation modes of the hot water supply combustion apparatus and a configuration of switching the modes according to the embodiment.

FIG. 13 shows a mode 1 to a mode 4 in the embodiment.
FIG. 7 is an explanatory diagram showing a flow of mutual switching of the operation states of FIG.

FIG. 14 is a block diagram showing a control configuration for closing a second flow rate control means in the embodiment.

FIG. 15 is a diagram illustrating the necessity of providing a mixing end prohibition time.

FIG. 16 is an explanatory diagram of an example of setting a mixing end prohibition time.

FIG. 17 is a block diagram of a configuration in which the second flow control means is indirectly closed by reducing the amount of feed forward heat.

FIG. 18 is an explanatory diagram of a setting example of a feedforward calorie for indirectly closing a second flow control unit.

FIG. 19 is a block diagram showing a structure for pushing and driving the second flow control means from the fully closed position in the closing direction at the end of mixing.

FIG. 20 is an explanatory diagram showing an example of a duty changing operation of the push-in closing drive voltage of the second flow control means.

FIG. 21 is a block diagram showing a configuration of switching control from the operation in mode 1 to the operation in mode 2 in FIG.

FIG. 22 is an explanatory diagram showing a peak temperature of hot water in a hot water supply heat exchanger in which overshoot and undershoot occur when hot water supply is started with the second flow control means closed.

FIG. 23 is an explanatory diagram schematically showing a configuration of a hot water supply combustion device prototyped earlier by the present applicant.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Hot-water supply heat exchanger 18 Water supply control bypass passage 28 Input temperature detection unit 34 Mixing control unit 52 Combustion control mode switching unit 53 Flow ratio combustion control unit 54 Total flow combustion control unit GM ₁ First flow control unit GM ₂ Second Flow control means

Claims (2)

[Claims] 1. A hot-water supply heat exchanger for heating water supplied from a water supply passage by a combustion flame of a burner to produce hot water and sending the hot water to the hot water supply passage, and a hot-water supply heat exchanger between the water supply passage and the hot water supply passage. A water supply control bypass passage bypassing the exchanger, a first flow control means for controlling a flow rate on the hot water side where water flowing out of the water supply control bypass passage joins, and a flow passage of the water supply control bypass passage. Second flow rate control means for controlling the water flow rate, post-boil detection means for detecting the post-boil temperature of the hot water in the hot water supply heat exchanger when the hot water supply combustion is stopped, and When the hot water supply is started in a state where the boiling is detected, the first
Control for controlling the valve opening degree of the flow rate control means and the second flow rate control means to control the flow ratio between the flow rate on the hot water side and the bypass control flow rate passing through the water supply control bypass passage in the direction of eliminating post-boiling. And a flow ratio combustion control unit that controls the burner combustion heat amount to a feedforward heat amount that raises the flow rate on the hot water side from a feed water temperature to a preset hot water supply set temperature. The amount of burner combustion heat added to the feedforward heat that increases the total flow rate supplied to the water supply passage from the water supply temperature to a preset hot water supply set temperature, plus the feedback heat for correcting the hot water supply temperature to the hot water supply set temperature. A total flow rate combustion control section to be controlled; and a flow rate ratio combustion control section when a mixing operation is performed by the mixing control section at the start of hot water supply. And a combustion control mode switching unit for performing combustion control by switching from the flow rate ratio combustion control unit to the total flow rate combustion control unit when the mixing operation by the mixing control unit is completed. Hot water supply combustion device characterized. 2. A hot water supply heat exchanger for heating water supplied from a water supply passage by a combustion flame of a burner to produce hot water and sending the hot water to the hot water supply passage, and a hot water supply heat exchanger between the water supply passage and the hot water supply passage. A water supply control bypass passage which bypasses the exchanger, and a first flow control means for controlling a flow on the hot water side where water flowing out from the water supply control bypass passage joins; and a flow passage for the water supply control bypass passage. A second flow rate control means for controlling a water flow rate, wherein the hot water supply combustion device has a post-boil detection function of detecting post-boilment of the hot water supply heat exchanger when the hot water supply combustion is stopped. When hot water supply is started from a state in which boiling is detected, the valve openings of the first flow rate control means and the second flow rate control means are controlled to flow the hot water side flow rate and the water supply control bypass passage. Increase the flow ratio with the flow rate in the direction of eliminating post-boiling A mixing mode operation unit for controlling; a steady operation mode operation unit for operating the valve opening of the first flow control unit and the second flow control unit to a preset steady position; and, during the mixing mode operation, When a predetermined mixing end condition is satisfied, a mode switching is performed in which the steady-state operation mode operation section is designated to shift the valve openings of the first flow control means and the second flow control means from the mixing operation state to the steady operation state. A hot water supply combustion device comprising: a control unit;