JP2009097730A - Automatic reheating device using hot water storage type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic reheating device using a hot water storage type water heater capable of reducing the number of times of operation of a pump necessary for measuring the temperature of hot water in a bathtub. <P>SOLUTION: A hot water temperature estimating means A estimates the temperature of hot water in the bathtub lowering after the stop of the operation of a bathtub circulation pump 79 on the basis of the hot water temperature measured by a temperature sensor 73, a lowering ratio ΔT of hot water temperature in the bathtub per a unit time and an elapsed time Cw counted by a time counter 82. The bathtub circulation pump 79 is re-operated when the time counter 82 completes the counting of a set time or the estimated hot water temperature estimated by the hot water temperature estimating means A becomes lower than a reference temperature (Ts-γ). The number of times of operation of the bathtub circulation pump 79 can be reduced without impairing accuracy in reheating operation. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an automatic reheating apparatus for hot water in a bathtub using a hot water storage type water heater.

Japanese Patent Laid-Open No. 2007-10217 discloses a conventional example of a reheating apparatus using a hot water storage type electric water heater. In this conventional apparatus, a first heat exchange member is provided in the hot water tank side circulation path, and a second heat exchange member is provided in the bathtub side circulation path. Then, the pump provided in the circulation path on the bathtub side is periodically operated to measure the hot water temperature in the bathtub, and when the hot water temperature decreases, the pump provided in the circulation path on the hot water storage tank side is operated to recharge. Is going.
JP 2007-10217 A

  When the hot water temperature in the bathtub is measured periodically, if it is attempted to increase the operation accuracy of the chase control, the measurement cycle is shortened. However, if the measurement period of the hot water temperature in the bathtub is shortened, the number of operations of the pump provided in the circulation path on the bathtub side increases, which causes a problem of shortening the pump life. Moreover, since heat is radiated in the circulation path every time the pump is operated, the operation for measuring the hot water temperature is a cause of lowering the hot water temperature.

  An object of the present invention is to provide an automatic reheating apparatus using a hot water storage type water heater that can reduce the number of operations of a pump necessary for measuring the temperature of hot water in a bathtub without reducing the accuracy of the reheating operation. It is to provide.

  An object of the present invention is to improve an automatic reheating apparatus using a hot water storage water heater that automatically reheats hot water in a bathtub by the amount of heat of hot water in a hot water storage tank of the hot water storage water heater. In the reheating apparatus of the present invention, a tank-side circulation path that is provided outside the hot water storage tank of the hot water storage water heater and connects the upper area and the lower area in the hot water storage tank, and a first that is provided in the circulation path A heat exchange member and a tank circulation pump provided in the circulation path are provided. Moreover, in the apparatus of this invention, it comprises between the 2nd heat exchange member provided so that heat exchange with the 1st heat exchange member and the 2nd heat exchange member was carried out, and it circulates between the interior space of a bathtub. The bathtub side circulation path which forms a path | route, and the bathtub circulation pump provided in the bathtub side circulation path are provided. Furthermore, in the apparatus of the present invention, a pump control device that controls both the tank circulation pump and the bathtub circulation pump, a temperature sensor that measures the temperature of the hot water in the bathtub when the bathtub circulation pump is operating, and a bathtub circulation pump And a time counter which starts counting time after stopping the operation.

  And in this invention, the pump control apparatus is provided with the hot water temperature prediction means which estimates the fall of the hot water temperature in a bathtub, and the control means which controls a tank circulation pump and a bathtub circulation pump. The hot water temperature predicting means stopped the bathtub circulation pump based on the measured hot water temperature measured by the temperature sensor, the rate of decrease in hot water temperature in the bathtub per unit time, and the elapsed time counted by the time counter. Predict the temperature of the hot water in the bathtub that falls later. The control means operates the bathtub circulation pump at the start of control. The control means, when the bathtub circulating pump is operated at the start of control and when the bathtub circulating pump is operated again thereafter, when the measured hot water temperature is equal to or lower than the first reference temperature lower than the set temperature. Then, the tank circulation pump is operated, and when the measured hot water temperature becomes equal to or higher than the second reference temperature higher than the set temperature, the tank circulation pump and the bathtub circulation pump are stopped. Further, the control means, when the bathtub circulating pump is operated at the start of control and when the bathtub circulating pump is operated again thereafter, when the measured hot water temperature is higher than the first reference temperature lower than the set temperature, The bathtub circulation pump is stopped, and then the bathtub circulation pump is restarted when the time counter finishes counting the set time or when the predicted hot water temperature falls below the third reference temperature lower than the first reference temperature. .

  In this invention, after a bathtub circulation pump stops operation | movement, the fall of the hot water temperature in a bathtub is estimated using a hot water temperature prediction means. In the present invention, when the time counter completes the count of the set time or the predicted hot water temperature falls below the third reference temperature, the bathtub circulation pump is restarted. Therefore, according to the present invention, even if the periodical operation cycle of the bathtub circulation pump is made longer than before, if the predicted hot water temperature predicted by the hot water temperature predicting means decreases rapidly, it becomes necessary to reheat. You can start chasing automatically. Therefore, the number of operations of the bathtub circulation pump can be reduced without lowering the accuracy of the chasing operation.

  The actual rate of decrease in hot water temperature varies depending on the season. Therefore, it is preferable to update (change) the rate of decrease in accordance with the actual state of decrease in hot water temperature. Therefore, the hot water temperature predicting means includes a measured hot water temperature storing means for storing the hot water temperature measured by the temperature sensor, a counter value storing means for storing the counter value of the time counter, and an initial value and an updated value of the hot water temperature decreasing rate. A reduction rate storage means for storing and a reduction rate calculation means are provided. The decrease rate calculation means is the current measurement measured by the previous measured hot water temperature and temperature sensor stored in the measured hot water storage means when the tank circulation pump is restarted after the tank circulation pump and the bathtub circulation pump are stopped. The rate of decrease obtained by dividing the difference from the hot water temperature by the counter value stored in the counter value storage means is calculated as the update value. The hot water temperature predicting means uses the value stored in the decrease rate storage means for predicting the hot water temperature. If it does in this way, since a fall rate will be changed according to the fall condition of actual hot water temperature, the precision of a chasing operation | movement can be raised more.

  The reduction rate calculation means preferably calculates the reduction rate on condition that the counter value is equal to or greater than a predetermined value. This is because if the counter value is too short, it can be fully inferred that the hot water temperature has decreased due to factors other than natural heat dissipation, so the rate of decrease in hot water temperature calculated under such circumstances cannot be used. This is because the operation accuracy is lowered.

  Moreover, you may further provide the water level recovery | restoration detection means which detects having recovered after the water level in a bathtub fell. However, in this case, it is preferable that the decrease rate calculation means not calculate the decrease rate when the bathtub circulation pump is restarted after the water level recovery detection means detects the recovery of the water level. This is because the water level is restored by adding water or hot water. That is, when the water level is recovered, the rate of decrease in hot water due to natural heat dissipation cannot be accurately calculated based on the previously stored temperature data.

  In the case where a function for performing a follow-up operation by manual input is provided, the follow-up operation by manual input may be given priority over the automatic follow-up operation. That is, when the chasing operation by manual input is performed, the auto chasing operation may be reset. When the chasing operation by manual input ends, the auto chasing operation may be resumed again.

  The present invention can also be applied to the case where the heat exchange member is arranged in the upper region in the hot water tank. In this case, a switching circuit, a circulation pump, a control device that controls both the circulation pump and the switching valve, a temperature sensor, and a time counter are used. The switching type circulation path includes a heat exchange member when reheating, and forms a recirculation circuit between the heat exchange member and the internal space of the bathtub. A non-reheating circulation path is formed by separating the heat exchange member from the heat exchanger. The circulation pump is provided in the switching circuit for hot water circulation in the reheating circuit and the non-reheating circuit. A temperature sensor is arrange | positioned in a switching-type circuit, and measures the hot water temperature in a bathtub, when the circulation pump is operate | moving. In this case, the time counter starts counting time after switching from the recirculation circuit to the non-recirculation circuit by the switching operation of the switching valve.

  The control device includes hot water temperature predicting means and control means. The hot water temperature predicting means is driven by the switching operation of the switching valve based on the measured hot water temperature measured by the temperature sensor, the decreasing rate of the hot water temperature in the bathtub per unit time, and the elapsed time counted by the time counter. The hot water temperature in the bathtub that decreases after switching from the circulation path to the non-reheating circulation path is predicted. And a control means performs the following control. First, in the state where the control valve is switched to the non-recirculation circuit by the switching operation of the switching valve at the start of the control, and then the switching valve is switched from the recirculation circuit to the non-recirculation circuit When the measured hot water temperature is equal to or lower than the first reference temperature lower than the set temperature, the switching operation of the switching valve switches the non-reheating circuit to the reheating circuit. Then, when the measured hot water temperature becomes equal to or higher than the second reference temperature higher than the set temperature, the switching valve is switched to switch from the recirculation circuit to the non-recirculation circuit, and the circulation pump is stopped. . Further, when the circulating pump is operated when the control valve is switched from the recirculation circuit to the non-recirculation circuit at the start of the control and thereafter, the measured hot water temperature is lower than the set temperature. When the temperature is higher than the reference temperature of 1, the circulation pump is stopped, and then the time counter finishes counting the set time, or when the predicted hot water temperature falls below the third reference temperature lower than the first reference temperature, The switching valve and the circulation pump are controlled to restart the circulation pump. When the control means operates in this way, the present invention can be applied to the case where the heat exchange member is disposed in the hot water tank.

  According to the present invention, when the time counter completes the counting of the set time or when the predicted hot water temperature falls below the third reference temperature, the bathtub circulation pump is restarted. If the predicted hot water temperature predicted by the hot water temperature predicting means decreases rapidly even when the hot water temperature is longer than the conventional temperature, the hot water can be automatically started when a situation requiring reheating is reached. Therefore, according to the present invention, the number of operations of the bathtub circulation pump can be reduced without lowering the accuracy of the chasing operation.

  An example of an embodiment of an automatic reheating apparatus using a hot water storage type hot water heater of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a system of a reheating apparatus using a hot water storage type water heater that replenishes hot water in a bathtub with the amount of heat of hot water in a hot water storage type water heater. FIG. 2 is a block diagram illustrating a configuration of a pump control device configured in the main control device 23. FIG. 3 is a diagram showing a software algorithm used in the system shown in FIG. 1 when automatic chase control is realized using a computer.

  In FIG. 1, a member denoted by reference numeral 1 is a hot water storage tank of a hot water storage type electric water heater that heats hot water using midnight power. A lower electric heater 3 that is used when boiling water in the hot water storage tank 1 using midnight power is disposed in the lower region of the hot water storage tank 1. A circulating water inlet 11 to which the lower end of the tank-side circulation path 9 is connected is formed at the center of the lower mirror plate 7 of the hot water storage tank 1, and a hot water outlet 15 is formed at the center of the upper mirror plate 13 of the hot water tank 1. Is formed. A hot water outlet pipe 17 is connected to the hot water outlet 15. The other end of the tank side circulation path 9 is connected to the hot water outlet pipe 17. A first heat exchange member 19 and a tank circulation pump 21 are disposed in the tank side circulation path 9. The tank circulation pump 21 is a pump that can change the circulation amount in accordance with a control command from the main control device 23.

  On the outer wall of the hot water storage tank 1, a temperature sensor 25 for detecting the temperature of the feed water is mounted on the lower region, and three remaining hot water amounts are detected on the upper region at intervals in the vertical direction. Sensors 27, 29 and 31 are mounted. A pressure switch 37 is disposed in a water supply pipe 35 connected to the water pipe 33 in the lower region of the hot water storage tank 1.

  The outlet pipe 17 includes a first electric mixing valve 41 and a second electric mixing valve 43 that mix tap water supplied from the water pipe 33 via the pressure reducing valve 39 and hot water supplied from the outlet pipe 17. Are connected to each other. The outlet of the first electric mixing valve 41 is connected to the bathtub-side circulation path 47 that replenishes the hot water in the bathtub 45 in series with the solenoid valve 49, the bathtub flow sensor 51, the vacuum breaker 53, and the double reverse. It is connected via a stop valve 55. The outlet of the second electric mixing valve 43 is connected to a shower / hot water outlet 57 in the bathroom having a mixing valve function, a hot water outlet 59 in the bathroom, and a hot water outlet 61 in the kitchen via a hot water pipe 63. ing. Tap water is supplied to the shower / hot water outlet 57 in the bathroom, the hot water outlet 59 in the bathroom, and the hot water outlet 61 in the kitchen via the water supply pipe 33. A relief valve 44 is connected to the hot water outlet pipe 17.

  A block denoted by reference numeral 67 is a bathtub remote controller disposed in the bathroom, and a block denoted by reference numeral 69 is a kitchen remote controller disposed in the kitchen. These remote controllers 67 and 69 are electrically connected to the main controller 23 and are used to set the hot water supply temperature and the amount of hot water.

  The second heat exchange member 20 that is combined with the first heat exchange member 19 and constitutes the heat exchanger 18 is disposed in the bathtub-side circulation path 47. And in the bathtub side circulation path 47, the 1st temperature sensor 71 which detects the temperature of the hot water on the exit side of the 2nd heat exchange member 20 is arrange | positioned. The bathtub side circulation path 47 is provided with a second temperature sensor 73 that detects the temperature of hot water on the inlet side of the second heat exchange member. Further, in the bathtub-side circulation path 47, between the bathtub 45 and the second temperature sensor 73, a flow switch 75 and a water level sensor 77 used for checking remaining hot water used for automatic hot water filling, and the bathtub 45 A bathtub circulation pump 79 used for circulating hot water is disposed.

  The main control device 23 includes a heater control device that controls energization of the lower heater 3 in order to boil hot water in the hot water storage tank 1 using midnight power, and hot water in the bathtub is used for hot water in the hot water storage tank 1. Both the pump control device 24 (see FIG. 2) for controlling the operation of the tank circulation pump 21 and the bathtub circulation pump 79 are included to perform additional heating (catch-up) using the amount of heat.

As shown in FIG. 2, the pump control device 24 includes a hot water temperature predicting means A that predicts a decrease in the hot water temperature in the bathtub 45, and a control means B that controls the tank circulation pump 21 and the bathtub circulation pump 79. Yes. The hot water temperature predicting means A includes a measured hot water temperature storing means 81, a time counter 82, a counter value storing means 83, a decrease rate calculating means 84, a decrease rate storing means 85, and a predictive calculating means 86. The hot water temperature predicting means A is based on the measured hot water temperature Tb measured by the temperature sensor 73, the decrease rate ΔT of the hot water temperature in the bathtub per unit time, and the elapsed time counted by the time counter 82. The hot water temperature in the bathtub 45 which falls after 79 stops operation | movement is estimated. The actual hot water temperature drop rate ΔT varies depending on the season. Therefore, the hot water temperature predicting means A of the present embodiment stores the measured hot water temperature measured by the temperature sensor 73 in the measured hot water temperature storing means 81. In addition, the counter value storage unit 83 stores the counter value counted by the time counter 82 that starts counting time after the bathtub circulation pump 79 stops operating. The rate-of-decrease calculating means 84 calculates the previous measured hot water temperature Tb _Bak stored in the measured hot water temperature storage means 81 when the tank circulation pump 79 is restarted after the tank circulation pump 21 and the bathtub circulation pump 79 are stopped. A reduction rate ΔT obtained by dividing the difference (Tb _Bak −Tb) from the current measured hot water temperature Tb measured by the temperature sensor 73 by the counter value Cw _Bak stored in the counter value storage means 83 is calculated as an update value. In the present embodiment, the decrease rate calculation means 84 calculates the decrease rate ΔT on condition that the counter value Cw _Bak is equal to or greater than a predetermined value. This is because if the counter value is too short, it can be fully inferred that the hot water temperature has decreased due to factors other than natural heat dissipation, so the rate of decrease in hot water temperature calculated under such circumstances cannot be used. This is because the operation accuracy is lowered. Then, the decrease rate storage means 85 stores the initial value and the updated value of the hot water temperature decrease rate ΔT. Further, the prediction calculation means 86 measures the hot water temperature decrease rate ΔT in the bathtub 45 per unit time stored in the decrease rate storage means 85, and is measured by the temperature sensor 73 and stored in the measured hot water temperature storage means 81. On the basis of the measured hot water temperature Tb _Bak and the elapsed time Cw counted by the time counter 82, the hot water temperature Tb ′ [= Tb _Bak − (ΔT × Cw) in the bathtub that decreases after the bathtub circulation pump 79 stops operating. ] Is calculated.

  The control means B operates the bathtub circulation pump 79 at the start of control. Then, the control means B operates the bathtub circulation pump 79, and when the measured hot water temperature Tb is lower than the first reference temperature RT1 = (Ts−α) (Tb ≦ RT1) lower than the set temperature Ts, When the tank circulation pump 21 is operated and the measured hot water temperature Tb becomes equal to or higher than the second reference temperature RT2 = (Ts + β) (Tb ≧ RT2) higher than the set temperature Ts, the tank circulation pump 21 and the bathtub circulation pump 79 are stopped. In addition, when the bathtub circulating pump 79 is operated, the control means B stops the bathtub circulating pump 79 when the measured hot water temperature Tb is higher than the first reference temperature RT1 lower than the set temperature Ts. When the counter 82 completes the count of the set time or when the predicted hot water temperature Tb ′ falls below the third reference temperature RT3 = (Ts−γ) lower than the first reference temperature RT1, (Tb ′ <RT3). The bathtub circulation pump 79 is restarted.

  In the present embodiment, after the bathtub circulation pump 79 stops operating, the hot water temperature predicting means A is used to predict a decrease in the hot water temperature in the bathtub 45. When the time counter 82 completes the count of the set time or when the predicted hot water temperature Tb ′ falls below the third reference temperature RT3 = (Ts−γ), the bathtub circulation pump 79 is restarted. Therefore, even if the periodic operation cycle of the bathtub circulation pump 79 is made longer than before, if the predicted hot water temperature Tb ′ predicted by the hot water temperature predicting means A is rapidly decreased, the automatic operation is performed when it becomes necessary to reheat. You can start chasing. Therefore, according to the present embodiment, the number of operations of the bathtub circulation pump 79 can be reduced as compared with the conventional one without lowering the accuracy of the chasing operation.

  Moreover, in this Embodiment, as shown in FIG. 2, the water level recovery | restoration detection means C which detects that it recovered after the water level in the bathtub 45 fell is further provided. Then, the drop rate calculating means 84 does not calculate the drop rate when the bathtub circulation pump 79 is restarted after the water level recovery detecting means C detects the recovery of the water level. This is because the water level is restored by adding water or hot water.

Next, an example of the software algorithm shown in FIG. 3 will be described. When the automatic chasing operation starts, first, the counter value Cw _Bak stored in the counter value storage means 83 is reset in step ST1. In step ST2, an initial value of the hot water temperature decrease rate ΔT stored in the decrease rate storage means 85 is set (ΔT update flag set / ON). In the present embodiment, the initial value of the decrease rate ΔT is 1 ° C./15 minutes. The initial value may be determined by a test and is arbitrary. Next, in step ST3, the bathtub circulation pump 79 is operated to check the remaining water in the bathtub 45 and the hot water temperature Tb. Next, the hot water temperature Tb in the bathtub 45 is measured at step ST4. In step ST5, it is determined whether the ΔT update flag is ON and the counter value Cw _Bak is equal to or longer than a predetermined time t1. As the predetermined time t1, it is preferable to set a time of 5 to 10 minutes, for example. In the first stage, since the condition is not satisfied in step ST5, the process proceeds to step ST7. In step ST7, when the bathtub circulating pump 79 is operated, whether or not the measured hot water temperature Tb is equal to or lower than the first reference temperature RT1 = (Ts−α) lower than the set temperature Ts (Tb ≦ RT1). A determination is made. Here, α is set to a value of 0.8 to 1.2 ° C., for example. At this time, if Tb ≦ RT1, that is, Yes, the process proceeds to step ST8 to operate the tank circulation pump 21. Next, the hot water temperature in the bathtub 45 is measured in step ST9. Next, in step ST10, it is determined whether or not the measured hot water temperature Tb is equal to or higher than the second reference temperature RT2 = (Ts + β) higher than the set temperature Ts (Tb ≧ RT2). If Tb ≧ RT2 is not satisfied (if No), the process returns to step ST9. Here, β is set to a value of 0.4 ° C. to 0.7 ° C., for example. If Tb ≧ RT2 (Yes), the tank circulation pump 21 is stopped (step ST11). As a result, the piping is cooled. Next, in step ST12, the ΔT update flag is set (ON). Further, in step ST13, the hot water temperature Tb _Bak is stored in the measured hot water temperature storage means 81. In step ST7, if Tb ≦ RT1, that is, if No, the process proceeds to step ST13.

  Next, the bathtub circulation pump 79 is stopped in step ST14. In step ST15, the counting operation of the time counter 82 is started. The time counter 82 counts the water level monitoring time (Cw).

Next, in step ST16, a predicted hot water temperature Tb 'is calculated. That is, the decrease rate ΔT of the hot water temperature in the bathtub 45 per unit time stored in the decrease rate storage means 85 and the measured hot water temperature Tb _Bak measured by the temperature sensor 73 and stored in the measured hot water temperature storage means 81. Based on the elapsed time Cw counted by the time counter 82, the predicted hot water temperature Tb ′ [= Tb _Bak − (ΔT × Cw)] in the bathtub that decreases after the bathtub circulation pump 79 stops operating is calculated. In step ST17, the predicted hot water temperature Tb 'falls below the third reference temperature RT3 = (Ts-γ) lower than the first reference temperature RT1 (Tb'<RT3), or the elapsed time Cw is determined in advance. It is determined whether or not the predetermined time t2 has been reached. Here, γ is set to a value of 1.0 to 1.5 ° C., for example. The predetermined time t2 is a water level monitoring time, and is set, for example, from 30 minutes to 45 minutes. When the condition of step ST17 is not satisfied, a decrease in water level ST18 is determined at step ST18. This drop in water level is determined by the water level sensor 77. When the drop in the water level cannot be determined (No), the process returns to step ST16. When it is determined that the water level is lowered (Yes), the process proceeds to step ST19 where water level recovery (additional hot water) is performed. Then, the process proceeds to step ST20, the ΔT update flag is cleared (OFF), and the process returns to step ST16. As a result, after the water level is recovered in step ST19 (water level recovery is detected), the condition of step ST5 is not satisfied even if the bathtub circulation pump 79 is restarted later. Does not proceed to step ST7. That is, the reduction rate is not calculated. This is because the water level is restored by adding water or hot water.

When the condition is satisfied in step ST17 (when a temperature decrease due to natural cooling is detected or a predetermined time t2 has elapsed), the counter value Cw _Bak is stored in the counter value storage unit 83 in step ST21. Then, it returns to step ST3 and the bathtub circulation pump 79 starts operation | movement. Then the process proceeds in step ST5, when it is determined detected and the counter value Cw _Bak of ΔT flag ON is t1 or more to step ST6. In step ST6, when the bathtub circulation pump 79 is restarted, the difference between the previous measured hot water temperature Tb _Bak stored in the measured hot water temperature storage means 81 and the current measured hot water temperature Tb measured by the temperature sensor 73 (Tb _Bak The decrease rate ΔT obtained by dividing -Tb) by the counter value Cw _Bak stored in the counter value storage means 83 is calculated as an update value. Then, the ΔT update flag is cleared (OFF). Then, it progresses to step ST7. Thereafter, the above operation is repeated.

  In the present embodiment, although not shown, when a function for performing a tracking operation by manual input is provided, the tracking operation by manual input has priority over the automatic tracking operation. That is, when the chasing operation by manual input is performed, the auto chasing operation is reset. When the chasing operation by manual input ends, the auto chasing operation is set again.

  FIG. 4 is a view showing a system of a reheating apparatus using the hot water storage type hot water heater of the embodiment to which the present invention is applied when the heat exchange member 18 ′ is arranged inside the hot water tank 1. 4, the same members as those constituting the embodiment shown in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and description thereof is omitted. The embodiment of FIG. 1 and the embodiment of FIG. 4 are that the heat exchange member 18 ′ is disposed inside the hot water tank 1 and that only the bathtub circulation pump 79 is used as a circulation pump. The switch circuit 9 ′ is provided with a three-way valve V as a switching valve. The switching circuit 9 ′ includes a heat exchange member 18 ′ at the time of reheating, forms a recirculation circuit between the heat exchange member and the internal space of the bathtub 45, and a three-way valve as a switching valve at the time of non-reheating. By switching V, a non-reheating circuit that separates the heat exchange member 18 ′ from the reheating circuit is formed. The bathtub circulation pump 79 as a circulation pump is used for circulating hot water in the reheating circulation path and the non-reheating circulation path.

  The basic configuration of the control device is almost the same as that shown in FIG. 2, but the time counter 82 in FIG. 2 changes from the recirculation circuit P1 to the non-reheating circuit P2 by the switching operation of the three-way valve V. Time counting starts after switching to. The hot water temperature predicting means A is based on the measured hot water temperature measured by the temperature sensor 73, the rate of decrease in hot water temperature in the bathtub 45 per unit time, and the elapsed time counted by the time counter 82. The hot water temperature in the bathtub 45 that decreases after switching from the reheating circulation path P1 to the non-reheating circulation path P2 is predicted. FIG. 5 is a diagram showing a software algorithm used in the system shown in FIG. 4 when automatic chase control is realized using a computer. In the algorithm of FIG. 5, the contents of the other steps are the same as the contents of the corresponding steps in FIG. 3 except for step ST8 ′ and step ST11 ′, and thus the description thereof is omitted.

  The operation and control flow of the control means B (FIG. 2) in the embodiment of FIG. 4 will be described below with reference to FIGS. First, at the start of control, the three-way valve V is switched to the non-reheating circuit P2 by the switching operation of the three-way valve V, and then the three-way valve V is switched from the reheating circuit P1 to the non-reheating circuit P2. In the state, when the bathtub circulation pump 79 as the circulation pump is operated (step ST3 ′), the first reference temperature RT1 = (Ts) where the measured hot water temperature Tb measured by the temperature sensor 73 is lower than the set temperature Ts. −α) or less (steps ST4 ′ to ST7 ′), the switching from the non-reheating circuit P2 to the reheating circuit P1 is performed by the switching operation of the three-way valve V (step ST8 ′). After that, when the measured hot water temperature Tb measured by the temperature sensor 73 becomes equal to or higher than the second reference temperature RT2 = (Ts + β) higher than the set temperature Ts (steps ST9 ′ and ST10 ′), it is used for reheating by the switching operation of the three-way valve V. Switching from the circulation path P1 to the non-reheating circulation path P2 is performed (step ST11 ′), and the bathtub circulation pump 79 as a circulation pump is stopped (steps ST12 ′ to ST14 ′). In addition, when the control is started and thereafter the three-way valve V is switched from the recirculation circuit P1 to the non-recirculation circuit P2, the measurement is performed when the bathtub circulation pump 79 as the circulation pump is operated. When the hot water temperature Tb is higher than the first reference temperature RT1 = (Ts−α) lower than the set temperature Ts (step ST7 ′), the bathtub circulation pump 79 as a circulation pump is stopped (step ST14 ′). Thereafter, the time counter 82 completes the counting of the set time, or the predicted hot water temperature Tb ′ is lower than the first reference temperature RT1 = (Ts−α) than the third reference temperature RT3 = (Ts−γ). If it falls (step ST17 '), the bathtub circulation pump 79 as the circulation pump is reactivated (steps ST21' and ST3 '). Other steps in the algorithm of FIG. 5 (steps for realizing the hot water temperature predicting means A, etc.) are the same as the description of each step shown in FIG. Also in the present embodiment, after the bathtub circulation pump 79 as the circulation pump stops operating, the hot water temperature predicting means A is used to predict a decrease in the hot water temperature in the bathtub 45. When the time counter 82 completes the count of the set time or when the predicted hot water temperature Tb ′ falls below the third reference temperature RT3 = (Ts−γ) (step ST17 ′), the bathtub circulation pump 79 as a circulation pump. Reactivate. Therefore, even if the periodic operation cycle of the bathtub circulation pump 79 as the circulation pump is made longer than before, if the predicted hot water temperature Tb ′ predicted by the hot water temperature predicting means A is rapidly decreased, it is necessary to reheat. Automatically start chasing. Therefore, also according to the present embodiment, the number of operations of the bathtub circulation pump 79 as a circulation pump can be reduced as compared with the conventional one without reducing the accuracy of the chase operation as in the first embodiment. Also in this embodiment, in order to employ the configuration shown in FIG. 2, water level recovery detection means C for detecting recovery after the water level in the bathtub 45 is lowered is further provided. Therefore, as shown in steps ST18 ′ to ST20 ′, the water level is recovered when the water level is lowered during the process.

It is a figure which shows the system of the reheating apparatus using the hot water storage type water heater which replenishes the hot water in a bathtub with the calorie | heat amount of the hot water in a hot water storage type water heater. It is a block which shows the structure of the pump control apparatus comprised in a main control apparatus. It is a figure which shows the algorithm of the software used when the chasing control is implement | achieved using a computer in the system of FIG. It is a figure which shows the other system of the reheating apparatus using the hot water storage water heater which reheats the hot water in a bathtub with the calorie | heat amount of the hot water in a hot water storage water heater. FIG. 5 is a diagram showing a software algorithm used in the system of FIG. 4 when the chasing control is realized using a computer.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hot water storage tank 9 Tank side circulation path 18 Heat exchanger 18 'Heat exchange member 19 1st heat exchange member 20 2nd heat exchange member 21 Tank circulation pump 47 Bathtub side circulation path 71 1st temperature sensor 73 2nd Temperature sensor 79 Bath circulation pump 24 Pump controller 81 Measurement hot water storage means 82 Time counter 83 Counter value storage means 84 Decrease rate calculation means 85 Decrease rate storage means 86 Prediction calculation means A Hot water temperature prediction means B Control means V Three-way valve ( Switching valve)

Claims (5)

An automatic reheating device using a hot water storage water heater that automatically heats the hot water in the bathtub using the amount of heat in the hot water storage tank of the hot water storage water heater,
A tank-side circulation path that is provided outside the hot water storage tank and connects an upper region and a lower region in the hot water storage tank;
A first heat exchange member provided in the tank-side circulation path;
A tank circulation pump provided in the tank side circulation path;
A second heat exchange member provided so as to be able to exchange heat with the first heat exchange member;
A bathtub-side circulation path that includes the second heat exchange member and forms a circulation path with the internal space of the bathtub;
A bathtub circulation pump provided in the bathtub-side circulation path;
A pump controller for controlling both the tank circulation pump and the bathtub circulation pump;
A temperature sensor that is arranged in the bathtub-side circulation path and measures the hot water temperature in the bathtub when the bathtub circulation pump is operating;
A time counter that starts counting time after the bathtub circulation pump stops operating,
The pump control device is configured such that the bathtub circulation pump is based on the measured hot water temperature measured by the temperature sensor, the rate of decrease in hot water temperature in the bathtub per unit time, and the elapsed time counted by the time counter. Hot water temperature predicting means for predicting the hot water temperature in the bathtub that drops after the operation is stopped;
When the bathtub circulation pump is operated at the start of control and the bathtub circulation pump is operated at the start of the control and when the bathtub circulation pump is restarted after that, the measured hot water temperature is lower than the set temperature. When the temperature is lower than the first reference temperature, the tank circulation pump is operated, and when the measured hot water temperature is equal to or higher than the second reference temperature higher than the set temperature, the tank circulation pump and the bathtub circulation pump are stopped. Further, when the measured hot water temperature is higher than the first reference temperature lower than the set temperature when the bathtub circulating pump is operated at the start of control and when the bathtub circulating pump is subsequently restarted. The bathtub circulation pump is stopped, and then the time counter completes the set time count or the predicted hot water temperature is the first reference temperature. A hot water storage hot water characterized by comprising: the tank circulation pump and a control means for controlling the bathtub circulation pump so as to re-activate the bathtub circulation pump when the temperature drops below a lower third reference temperature Automatic chasing device using a container.   The hot water temperature predicting means includes a measured hot water temperature storing means for storing the measured hot water temperature by the temperature sensor, a counter value storage means for storing a counter value of the time counter, and an initial value of the rate of decrease in the hot water temperature. A decrease rate storage means for storing an updated value, and the previous measured hot water stored in the measured hot water temperature storage means when the tank circulation pump is restarted after the tank circulation pump and the bathtub circulation pump are stopped. A rate-of-decrease calculating unit that calculates a rate of decrease obtained by dividing the difference between the temperature and the current measured hot water temperature measured by the temperature sensor by the counter value stored in the counter value storing unit as the updated value; 2. The automatic reheating device using a hot water storage type hot water heater according to claim 1, wherein a value stored in the reduction rate storage means is used for prediction of the hot water temperature.   3. The automatic reheating apparatus using a hot water storage type hot water heater according to claim 2, wherein the decrease rate calculation means calculates the decrease rate on condition that the counter value is equal to or greater than a predetermined value. It further comprises water level recovery detection means for detecting that the water level in the bathtub has recovered after the water level has dropped,
The said reduction rate calculation means does not calculate the said reduction rate when the said bathtub circulation pump restarts after the said water level recovery | restoration detection means detects the recovery | restoration of the said water level. An automatic reheating device using a hot water heater. An automatic reheating device using a hot water storage water heater that automatically heats the hot water in the bathtub using the amount of heat in the hot water storage tank of the hot water storage water heater,
A heat exchange member provided in the upper region in the hot water storage tank;
A recirculation circuit is formed between the heat exchange member and the interior space of the bathtub when reheating, and a recirculation circuit is formed between the heat exchange member and the internal space of the bathtub. A switchable circuit that forms a non-reheating circuit with the heat exchange member separated;
A circulation pump provided in the switching circuit for circulating hot water in the recirculation circuit and the non-recirculation circuit;
A control device for controlling both the circulation pump and the switching valve;
A temperature sensor disposed in the switchable circulation path for measuring the hot water temperature in the bathtub when the circulation pump is operating;
A time counter that starts counting time after being switched from the reheating circuit to the non-reheating circuit by the switching operation of the switching valve;
The control device switches the switching valve based on the measured hot water temperature measured by the temperature sensor, the rate of decrease in hot water temperature in the bathtub per unit time, and the elapsed time counted by the time counter. Hot water temperature predicting means for predicting the hot water temperature in the bathtub that drops after being switched from the reheating circuit to the non-reheating circuit,
A state in which the switching valve is switched to the non-reheating circuit at the start of control and a state in which the switching valve is subsequently switched from the reheating circuit to the non-reheating circuit When the circulating pump is operated, if the measured hot water temperature is equal to or lower than a first reference temperature lower than a set temperature, the switching valve is operated to switch the reheating circuit from the non-reheating circuit. After switching to the circulation circuit, when the measured hot water temperature is equal to or higher than a second reference temperature higher than the set temperature, the switching valve is switched to switch the non-recirculation circuit from the recirculation circuit. In a state where the circulation pump is stopped and the switching valve is switched from the recirculation circuit to the non-recirculation circuit at the start and after the control. When the circulating pump is operating, if the measured hot water temperature is higher than the first reference temperature lower than the set temperature, the circulating pump is stopped, and then the time counter completes the set time count. Or when the predicted hot water temperature falls below a third reference temperature lower than the first reference temperature, control means for controlling the switching valve and the circulation pump so as to restart the circulation pump; An automatic reheating device using a hot water storage type water heater characterized by comprising.

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