JP2002005511A - Method for discriminating presence/absence of remaining water in bathtub - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method by which the presence/absence of remaining water in a bathtub can be discriminated, within the required minimum time. SOLUTION: After a circulating path 3 from the circulating port 1a of the bathtub 1 to the suction port of a circulating pump 12 is almost filled with water by supplying a prescribed quantity of water to the path 3 from a water- supplying path 2a, in a state where the bathtub 1 is maintained in an almost empty state, the pump 12 is actuated and the time until a water flow switch 13 is turned off (water flow turn-off time) is measured. At discrimination of the presence of remaining water in the bathtub 1 thereafter, whether remaining water exists in the bathtub 1 is discriminated, according to the on/off state of the switch 13, when remaining water presence/absence discriminating time which is determined, according to the water flow turning-off time elapses after the operation of the pump 12 is started.

Description

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a method for determining the presence or absence of residual water in a bathtub.

2. Description of the Related Art In an apparatus for automatically filling a bathtub or boiling water, a circulation path is connected to a circulation port formed at a lower portion of a side wall of the bathtub. A circulation pump for circulating water through the circulating passage, a heat exchanger for heating hot water in a bathtub circulating through the circulation path, and the like are provided. Further, a water supply path for supplying water (including hot water) to the bathtub when hot water or hot water is supplied is connected to the circulation path. In this type of apparatus, it is necessary to appropriately determine whether or not there is residual water in the bathtub in order to perform the hot water filling operation and the like. For example, when performing automatic filling operation,
Since the amount of water to be supplied to the bathtub and the manner of supplying the water differ depending on whether the bathtub has residual water or not, the presence or absence of residual water is determined at least at the initial stage of the automatic hot water filling operation sequence. There is a need. In addition, when performing the boiling operation, the boiling operation is actually started in order to avoid a situation in which the boiling operation is performed with little residual water in the bathtub due to a user's erroneous operation or the like. It is a common practice to determine the presence or absence of residual water in a bathtub before performing. As a method for determining the presence or absence of residual water, for example, the following method has been conventionally used. That is, the circulation path of the bathtub is provided with a water flow switch that is turned on / off in accordance with the presence or absence of the water flow. When determining the presence or absence of residual water in the bathtub, the detection signal of the water flow switch is observed while operating the circulation pump in the circulation path. At this time, if there is residual water in the bathtub (specifically, if there is residual water at a level higher than the circulation port), the circulation pump continuously supplies water to the circulation path. After the operation of the circulation pump is started, the ON state is continuously maintained. On the other hand, when there is no remaining water in the bathtub beyond the circulation port, the water flow switch is turned ON while the hot water already existing in the circulation path is flowing through the water flow switch by the operation of the circulation pump. When the hot water finally flows into the bathtub and the hot water stops flowing at the position of the water flow switch, the water flow switch is turned off. Therefore, if the water flow switch is turned on when a predetermined time (hereinafter, referred to as a remaining water presence / absence determination time) elapses after the operation of the circulating pump is started, the remaining water in the bathtub is removed. It is determined that there is no remaining water in the bathtub if the water flow switch is OFF when the predetermined time has elapsed. Thereby, the presence or absence of the remaining water in the bathtub can be determined. By the way, when there is no remaining water in the bathtub, when the circulation path is almost filled with hot water, the time from the start of the operation of the circulation pump to the turning off of the water flow switch is determined by the length of the circulation path (details). Varies from the circulation port to the suction port of the circulation pump).
The longer the length of the circulation path, the longer the time until the water flow switch is turned off. In addition, the length of the circulation path varies depending on the structure of the house near the installation location of the bathtub. For this reason, conventionally, the length of the circulation path is
The remaining water presence / absence determination time is set in consideration of the longest case. That is, even when the length of the circulation path is the longest and the circulation path is filled with hot water, when there is no residual water in the bathtub, the residual water presence / absence determination time has elapsed since the operation of the circulation pump was started. Sometimes the water flow switch is O
The remaining water presence / absence determination time is set in advance to a time when FF is performed. If the remaining water presence / absence determination time is set in this way, even when the length of the circulation path is short, when there is no remaining water in the bathtub, the water flow switch is turned off when the remaining water presence / absence determination time has elapsed. Therefore, the presence or absence of residual water in the bathtub can be determined regardless of the length of the circulation path. However, in the related art in which the remaining water presence / absence determination time is set as described above, even when the length of the circulation path is relatively short, the determination of the presence / absence of residual water is performed after the start of the operation of the circulation pump.
This is not performed unless the above-described remaining water presence / absence determination time has elapsed.
Therefore, there is an inconvenience that it often takes a longer time than necessary to determine the presence or absence of residual water. If it takes a long time to determine the presence or absence of residual water, the time required for various operations such as an automatic hot water filling operation becomes longer.

SUMMARY OF THE INVENTION The present invention has been made in view of the above background, and a method for determining the presence or absence of residual water in a bathtub which can determine the presence or absence of residual water in a bathtub in a short time as necessary. The purpose is to provide.

In order to achieve the above object, the method of the present invention for determining the presence or absence of residual water in a bathtub is connected to a circulation port provided in a side wall of the bathtub, and circulates water in the bathtub by a circulation pump. A bath provided with a circulation path, a water flow detection means for detecting the presence or absence of a water flow in the circulation path, and a water supply path connected to the circulation path so that water can be supplied to the bathtub through the circulation path. A method for determining whether or not there is residual water having a water level equal to or higher than the circulation port in the bath tub based on a detection output of the water flow detecting unit in a state where a circulation pump is operated, wherein the bath tub is substantially empty. A first step of supplying a predetermined amount of water from the water supply path to the circulation path at least in a state from the circulation port of the circulation path to the suction port of the circulation pump in the state described above,
Then, the circulation pump is operated, and a second step of measuring the time from the start of the operation to the absence of water flow in the circulation path by the water flow detection means is provided. When determining the presence / absence of residual water in the bathtub while operating the circulation pump later, the remaining water presence / absence determination time set according to the time detected in the second step after the operation of the circulation pump has elapsed. The presence or absence of the residual water is determined based on the detection output of the water flow detecting means at the time. According to the present invention, after a predetermined amount of water is supplied to the circulation path in the first step, a circulation pump is operated in the second step, and after the operation is started, the circulation pump is circulated by the water flow detection means. When measuring the time until it is detected that there is no water flow in the path, the measured time is the length of the circulation path (more specifically, the length of the point from the circulation port of the circulation path to the suction port side of the circulation pump). ), And the longer the circulation path, the longer the measurement time. In the present invention, the remaining water presence / absence determination time for determining the presence / absence of residual water in the bathtub after the second step, that is, the determination of the presence / absence of residual water in the bathtub after the operation of the circulation pump is started. Since the time until the measurement is performed is set according to the measurement time, the remaining water presence / absence determination time corresponding to the length of the circulation path can be set, and the length of the remaining water presence / absence determination time is kept to a minimum. Can be. Specifically, by setting the remaining water presence / absence determination time to a shorter time as the time measured in the second step is shorter, the shorter the length of the circulation path, the more the operation of the circulation pump is started. The determination of the presence or absence of residual water can be performed in a short time. Therefore, according to the present invention, the determination of the presence or absence of residual water in the bathtub can be performed in a minimum necessary time.
In the present invention, the predetermined amount of water supplied to the circulation path in the first step may be at least a point from the circulation port of the circulation path to the suction port of the circulation pump even in the circulation path considered to be the longest. It is preferable to set the water supply amount such that the water supply amount can substantially be satisfied. Further, the first step and the second step are preferably performed, for example, immediately after the installation of the bathtub, but may be performed at an arbitrary timing after the installation of the bathtub (for example, during an automatic hot water filling operation). It may be. In the present invention, preferably, the remaining water presence / absence determination time is a first remaining water presence / absence determination time corresponding to a case where it is determined that there is remaining water in the bathtub, and a case where it is determined that there is no remaining water in the bathtub. There is a second remaining water presence / absence determination time corresponding to the above, and the first remaining water presence / absence determination time is set to a time longer than the second remaining water determination time. In other words, in a device for performing automatic filling of a bathtub or the like, when it is determined that there is residual water in the bathtub, additional heating or boiling operation of the bathtub may be automatically performed. It is required to ensure that there is residual water. On the other hand, when it is determined that there is no remaining water in the bathtub, the bathtub is usually supplied with water, so that the bathing is quickly performed. It is required to determine that there is no such information. For this reason, in the present invention, the remaining water presence / absence determination time when determining that there is residual water in the bathtub is set to a longer time, and conversely, the remaining water presence / absence determination time when determining that there is no residual water in the bathtub is set. Set a short time. By doing so, it is possible to more accurately determine when there is residual water in the bathtub, and to more quickly determine when there is no residual water in the bathtub. In the present invention, it is preferable that the remaining water presence / absence determination time is set to a time equal to or longer than a predetermined lower limit. In other words, if air remains in the circulation path, even if there is residual water in the bathtub, the flow of water through the circulation path detected by the water flow detection means at a relatively early stage after the operation of the circulation pump is temporarily stopped. Sometimes. In such a case, if the remaining water presence / absence determination time is too short, when the water flow detecting unit temporarily detects that there is no water flowing through the circulation path, it is erroneously determined that there is no remaining water. There is a risk of doing this. Therefore, in the present invention, a lower limit value of the remaining water presence / absence determination time is provided, and the determination of the remaining water presence / absence is not performed in a time shorter than the lower limit value. Thus, it is possible to avoid a situation in which erroneous determination of the presence or absence of residual water is performed due to the influence of air or the like remaining in the circulation path, and it is possible to enhance the reliability of the determination result of the presence or absence of residual water.

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention is shown in FIGS.
This will be described with reference to FIG. FIG. 1 is an overall system configuration diagram of an apparatus to which the method of the present invention is applied, and FIGS. 2 to 5 are flowcharts for explaining the operation of the apparatus of FIG. Referring to FIG. 1, the device in the present embodiment is a bath water heater, and includes a water supply channel 2 for supplying (including hot water) water to bathtub 1 and the like, and a circulation channel 3 for circulating hot and cold water in bathtub 1. ing. The water supply channel 2 is provided via a hot water supply heat exchanger 5 heated by a gas burner 4, and the upstream side thereof is connected to a water pipe (not shown). Further, the water supply channel 2 is a downstream side of the hot water supply heat exchanger 5, a bath water supply channel 2 a for supplying water to the bathtub 1, and a regular water supply channel 2 for supplying water to a kitchen or a washroom.
b. And the water supply channel 2a for the bath is
A solenoid valve 6 for opening and closing the valve, a check valve 7 for preventing backflow of hot water from the circulation path 3 to the bath water supply path 2a, and a flow sensor for detecting a flow rate (flow rate) of the bath water supply path 2a 8 is connected to the circulation path 3. In addition, regular water supply channel 2b
Is connected to a hot water tap (not shown) such as a kitchen or a washroom. The circulation path 3 is connected to a circulation port 1 a provided in a lower part of the side wall of the bathtub 1, and is provided via a bath heat exchanger 10 heated by a gas burner 9. A water level sensor 11 for detecting the water level of the hot water in the bathtub 1 and a hot water in the bathtub 1 are provided in a position of the circulation path 3 from the circulation port 1 a to the inlet side of the bath heat exchanger 10. And a water flow switch 13 as water flow detection means for detecting the presence or absence of water flow in the circulation path 3
And a temperature sensor 14 for detecting the temperature of hot and cold water in the bathtub 1 flowing into the bath heat exchanger 10 are provided in order from the bathtub 1 side. Here, the water level sensor 11 is a sensor that generates an output signal corresponding to the hydrostatic pressure of a portion provided with the water level sensor as an output signal indicating the level of the hot water in the bathtub 1. In addition, the water flow switch 13 is used for water flow (water flow) at a location provided with the water flow switch 13.
The sensor turns ON when there is water, and turns OFF when there is no water flow. In addition, the apparatus of the present embodiment includes a controller 15 that controls the operation of the entire bath water heater, including a process of determining the presence / absence of residual water in the bathtub 1 described below, and a controller 15 that controls the operation mode of the apparatus by the user. A remote controller 16 for giving an instruction is provided. The controller 15 is constituted by using a microcomputer, and the water level sensor 1
1, water flow switch 13, temperature sensor 14, flow sensor 8
Circulating pump 12, solenoid valve 6, gas burners 4, 9 based on detection data of various sensors such as
This controls the combustion operation of the engine. In this case, the remote controller 16 may be operated by a switch (not shown), for example, in an automatic filling operation mode for automatically filling the bathtub 1, or immediately after installation of the bath water heater of the present embodiment. Can select an operation mode such as a test operation mode for checking the operation of the apparatus. Furthermore, for example, a target water level and a target hot water temperature of the bathtub 1 and a target hot water temperature of the water supply channel 2 can be set. Although not shown, a gas proportional solenoid valve for adjusting a gas supply amount and a gas supply passage are opened and closed in the gas supply passages to the gas burners 4 and 9 in relation to the gas burners 4 and 9. Igniter for igniting each gas burner 4, 9; a flame detector for detecting the combustion flame of each gas burner 4, 9; and supplying combustion air to each gas burner 4, 9 Fan and the like are provided. And
The combustion operation of each gas burner 4, 9 is controlled via these devices. Next, the operation of the device of the present embodiment will be described with reference to the flowcharts of FIGS. For example, immediately after the installation of the apparatus (including the bathtub 1) of the present embodiment, the operation mode of the test operation mode is selected by the remote controller 16 and the operation mode is instructed to the controller 15;
By the control processing of the controller 15, the test operation of the bath water heater is performed as shown in the flowcharts of FIGS. That is, first, in STEP 1, a predetermined amount (for example, 10 liters) of water is supplied to the bathtub 1 side in order to substantially fill the water from the circulation port 1 a of the circulation path 3 to the suction port side of the circulation pump 12. Done.
That is, the controller 15 opens the solenoid valve 6 of the bath water supply passage 2a to open the gas burner 4 on the hot water supply heat exchanger 5 side.
The hot water heated by the hot water supply heat exchanger 5 is supplied to the circulation path 3 (hot water supply) while performing the combustion operation of. This water supply is performed until the integrated amount of the flow rate detected by the flow rate sensor 8 of the bath hot water supply path 2a reaches 10 liters. At this time, immediately after the installation of the bath water heater, the bathtub 1 and the circulation path 3 are basically empty. In addition, the amount of water supply (10 liters) in STEP 1 is the maximum length that the length of the circulation path 3 can tolerate in the bath water heater of the present embodiment (hereinafter, referred to as “water supply amount”).
Even if it is the maximum allowable length of the circulation path 3), the water supply amount is determined in advance to such an extent that at least a portion from the circulation port 1a of the circulation path 3 to the suction port side of the circulation pump 12 can be substantially filled with water. I have. In this STEP 1, water may be supplied to the circulation path 3 without performing the combustion operation of the gas burner 4. Next, in STEP 2, the controller 15 controls the circulating pump 12 to start the operation of the circulating pump 12, and starts a timer for measuring an elapsed time from the start of the operation of the circulating pump 12. Then, the controller 15 operates the circulation pump 12 and the timer as described above,
The output of the water flow switch 13 is monitored in TEP3, and it is determined whether or not the water flow switch 13 has been turned off.
At this time, if the bathtub 1 is almost empty (specifically, there is no water in the bathtub 1 in an amount exceeding the level of the circulation port 1a), the hot water in the circulation path 1 Is discharged into the bathtub 1 while flowing in the circulation path 1 by the operation of the circulation pump 12. At this time, while the hot water in the circulation path 1 is flowing through the circulation path 1 by the operation of the circulation pump 12 in STEP 1, the water flow switch 13
Is turned on, the hot water in the circulation path 1 is sent into the bathtub 1 and the hot water stops flowing in the circulation path 1, and the water flow switch 13 is turned off. Then, the controller 15 executes STEP 3
When the water flow switch 13 is turned off, the count time of the timer started in STEP 2, that is, the elapsed time from the start of the operation of the circulation pump 12 until the water flow switch 13 is turned off (hereinafter referred to as the water flow OFF time) is set in STEP.
At 4, a comparison is made with a predetermined time (for example, 60 seconds). In this case, in the device of the present embodiment, the circulation path 3
Even if the length is the maximum allowable length, when the bathtub 1 is almost empty, the water flow OFF time basically does not exceed the predetermined time (60 seconds) by an experiment or the like in advance. Has been verified. Therefore, if the water flow OFF time exceeds 60 seconds in STEP 4, the controller 15 outputs error information to a display (not shown) or the like in STEP 5, and then stops the test operation of the bath water heater. On the other hand, in STEP4, the water flow OFF time was 6 hours.
If the time is 0 second or less, in step 6, the water flow OFF time (the count time of the timer when the water flow switch 13 is turned off in step 3) is stored and held as the value of the parameter Tm.
2 is stopped. In this case, the water flow OFF time Tm stored and held in STEP 6 basically depends on the length from the circulation port 1a of the circulation path 3 to the suction port side of the circulation pump 12, and thus the circulation path 3 Will depend on the overall length of the That is, the longer the circulation path 3 is, the longer the water flow OFF time Tm is. In addition, this water flow O
The value of the FF time Tm is stored and held in a non-volatile memory such as an EEPROM so that data is not lost even during a power failure or the like. Next, in STEP 8, for example, 5
Water supply (hot water supply) of 0 liter is performed to the bathtub 1. That is, the controller 15 opens the solenoid valve 6 of the bath water supply passage 2a to perform the combustion operation of the gas burner 4 on the side of the hot water supply heat exchanger 5 in the same manner as in the case of STEP 1 described above. Hot water heated by the exchanger 5 is supplied to the bathtub 1 via the circulation path 3 (hot water supply). This water supply is performed until the integrated amount of the flow rate detected by the flow rate sensor 8 in the bath hot water supply passage 2a reaches 50 liters. Then, in STEP 9, the presence or absence of residual water in the bathtub 1 (the circulation port 1a)
The controller 15 determines whether or not the above level of hot water is present in the bathtub 1). This determination is made according to FIG.
Is performed as shown in the flowchart of FIG. That is,
First, the controller 15 performs the first operation in accordance with the water flow OFF time Tm stored and stored in STEP 6 according to, for example, a predetermined data table as shown in Table 1.
And the second two types of remaining water presence / absence determination times Ta, Tb are set, and the operation of the circulation pump 12 is started (S
TEP30).

[Table 1] In this case, the first and second remaining water presence / absence determination times Ta, Tb
Are used when it is determined that there is residual water as described below, and when it is determined that there is no residual water. The shorter the time Tm (the shorter the circulation path 3), the shorter the time. The remaining water presence / absence determination times Ta and Tb may be set according to Table 1 immediately after the water flow OFF time Tm is determined in STEP 6 and may be stored and held. Next, the controller 15
After activating the circulation pump 12 in STEP 31 and starting the timer, the state of the water flow switch 13 is sequentially monitored in STEP 32. If the water flow switch 13 is ON at this time, the current count time of the timer started in STEP 31 is compared with the first remaining water presence / absence determination time Ta in STEP 33, and the count time If the (elapsed time after the start of the operation of the circulation pump 12) is equal to or longer than the first remaining water presence / absence determination time Ta, it is determined that there is remaining water in the bathtub 1 at a level equal to or higher than the circulation port 1a (STEP 34). . Also, S
If the count time of the timer is less than the first remaining water presence / absence determination time Ta in STEP 33, the process returns to STEP 32, and monitoring of the output of the water flow switch 13 is continued. On the other hand, STE
When the water flow switch 13 is in the OFF state in P32, the controller 15 sets the current count time of the timer to the second remaining water presence / absence determination time Tb in STEP35.
If the count time (elapsed time after the start of the operation of the circulation pump 12) is equal to or longer than the second remaining water presence / absence determination time Tb, it is determined that there is no remaining water in the bathtub 1 (STEP
36). If the count time of the timer is less than the second remaining water presence / absence determination time Tb in STEP 35, the STE
Returning to P32, monitoring of the output of the water flow switch 13 is continued. After determining the presence or absence of residual water as described above, the controller 15 stops the operation of the circulation pump 12 in STEP 37. By the above processing,
When the first remaining water presence / absence determination time Ta has elapsed since the operation of the circulation pump 12 was started, the water flow switch 13 was turned on.
If it is in a state, it is determined that there is residual water in the bathtub 1 at a level equal to or higher than the circulation port 1a. If the water flow switch 13 is OFF when the second remaining water presence determination time Tb has elapsed since the operation of the circulation pump 12 was started, it is determined that there is no remaining water in the bathtub 1. You. At this time,
First residual water presence / absence determination time Ta and second residual water presence / absence determination time T
b is that the shorter the water flow OFF time is, the longer the circulation path 3 is.
The shorter the length, the shorter the time is set. Therefore, it is possible to determine the presence or absence of residual water in a necessary short time after the operation of the circulation pump 12 is started. In the present embodiment, as shown in Table 1, the first remaining water presence / absence determination time Ta is set to be longer than the second remaining water presence / absence determination time Tb. Therefore, the following effects are obtained. That is, even if there is residual water at a level higher than the circulation port 1a in the bathtub 1, air may partially exist in the circulation path 3, and in such a case, the circulation path The water flow switch 13 may be temporarily turned off due to the influence of the air inside 3. However, in the present embodiment, since the first remaining water presence / absence determination time Ta related to the determination of the presence of remaining water is set to a longer time, the air in the circulation path 3 moves from the circulation path 3 to the bathtub 1 side. In the state where only hot and cold water flows through the circulation path 3, it is possible to determine whether there is residual water, and to make the determination accurately. The reason why the determination of the presence of residual water is made accurately is that the determination result has a great effect on the normal operation of the bath water heater. Further, in the present embodiment, as shown in Table 1, the second remaining water determination time Tb
Has a lower limit (30 seconds in the present embodiment), and the second remaining water determination time Tb is a time equal to or longer than the lower limit, and is set according to the water flow OFF time. In the present embodiment, the first remaining water presence / absence determination time Ta is set to be longer than the second remaining water presence / absence determination time Tb. Value (30 seconds)
The above time is set. By providing the first and second remaining water presence / absence determination times Ta and Tb with the lower limit values as described above, the following effects can be obtained. That is, especially bathtub 1
If there is no residual water at a level equal to or higher than the circulation port 1a, the circulation path 3 generally contains air and hot water in many cases. In many cases, the ON / OFF state of the switch 13 is frequently switched. However, in the present embodiment, the circulation pump 1
Since the determination of the presence or absence of residual water is not performed before the time of the lower limit (30 seconds) has elapsed since the start of the operation of Step 2, the determination of the presence or absence of residual water is performed when the state of the water flow switch 13 is stabilized. Can be performed. Therefore, the reliability of the determination result can be improved. Returning to the description of the flowchart of FIG. 2, after performing the process of determining the presence or absence of residual water in STEP 9 as described above, the controller 15
In P10, the result of the determination is confirmed. At this time,
When it is determined that there is no remaining water, the controller 15
At STEP 11, it is determined whether or not the integrated water supply amount after starting the water supply at STEP 8 has reached a predetermined amount (for example, 500 liters). At this time, if the accumulated water supply amount is less than 500 liters, the process returns to STEP 8 to supply 50 liters of water to the bathtub 1 again. Is determined. Also, in STEP 11,
If the accumulated amount of water supplied to the bathtub 1 after the start of the water supply in STEP 8 has reached 500 liters, there is a possibility that an inconvenience such as a plug (not shown) of the drain port of the bathtub 1 has been removed. Therefore, after outputting error information to a display or the like (not shown) (STEP 12), the test operation of the bath water heater is stopped. As described above, in STEPs 9 to 12, the bathtub 1 is intermittently supplied with water (hot water supply) by 50 liters at a time until the determination result that there is residual water having a level equal to or higher than the circulation port 1a in the bathtub 1 is obtained. Each time the water is supplied, the presence or absence of remaining water is determined. Then, when the accumulated water supply amount to the bathtub 1 (the accumulated water supply amount after starting the 50 liter water supply) reaches 500 liters without obtaining the determination result that there is residual water, the test operation of the apparatus is started. Stopped. Next, a determination result indicating that there is residual water is obtained in STEP 9, and when it is confirmed in STEP 10, the controller 15 determines in STEP 13 that the water level sensor 11
The current output (water level detection value) is stored and held as a reference water level, and the integrated water supply amount from the start of water supply in STEP 8 to the present (this is necessary for performing bathing up to the reference water level in the bathtub 1). (Which is the amount of water supply). The reference water level is a reference value of the target water level set by the remote controller 16. The reference water level and the accumulated water supply amount up to the present are stored and held in a non-volatile memory such as an EEPROM (not shown). Next, STEP1
In 4, for example, 20 liters of water (hot water) is supplied to the bathtub 1. That is, the controller 15 opens the solenoid valve 6 of the bath water supply passage 2a to perform the combustion operation of the gas burner 4 on the side of the hot water supply heat exchanger 5 in the same manner as in STEPs 1 and 8 described above. The hot water heated by the heat exchanger 5 is supplied to the bathtub 1 via the circulation path 3 (hot water supply). This water supply is performed until the integrated amount of the flow rate detected by the flow rate sensor 8 of the bath hot water supply path 2a reaches 20 liters. Then, in STEP 15, the determination of the presence or absence of residual water in the bathtub 1 (whether or not hot water having a level equal to or higher than the circulation port 1 a is present in the bathtub 1) is performed by the controller 15 in exactly the same manner as in STEP 9 described above. . in this case,
As in STEP 9, the determination of the presence or absence of residual water can be made in a necessary short time that matches the length of the circulation path 3, and a highly reliable determination result can be obtained. Then, in STEP 16, the controller 15 confirms the determination result of the presence or absence of residual water. At this time, if the determination result is that there is no remaining water, there is a possibility that hot water leaks from the bathtub 1 or the like, so the controller 15 outputs error information to a not-shown display or the like ( STEP
17) Stop the test run of the device. On the other hand, when the determination result that there is residual water is obtained, the controller 15
Detects the current water level of the bathtub 1 based on the output of the water level sensor 11 in STEP 18 and calculates a deviation (= STE) between the detected water level and the reference water level obtained in STEP 13.
The amount of rise in the water level of the bathtub 1 due to the water supply in P14) and the STE
From the water supply amount (20 liters) in P14, bathtub 1
(Water supply amount / water level rise amount) is calculated. The calculated cross-sectional area of the bathtub 1 is stored in an EEPROM (not shown).
Etc. are stored and held in a non-volatile memory. Then, STE
In P19, the controller 15 determines the deviation between the target water level of the bathtub 1 set by the remote controller 16 and the current water level of the bathtub 1 previously detected in STEP 18 (= the amount of water level rise required from the current water level to the target water level) and From the sectional area of the bathtub 1 previously calculated in STEP18, the shortage hot water amount from the current water level to the target water level is calculated. In addition, when the cross-sectional area of the bathtub 1 is constant in the depth direction, the shortage of hot water may be determined as the product of the above-mentioned rise in water level and the cross-sectional area. In the case of a change in the vertical direction, for example, the change rate of the cross-sectional area per unit depth of the bathtub 1 is stored in the controller 15 in advance, and the amount of hot water to the target water level is determined in consideration of the change rate of the cross-sectional area. You may ask for it. Next, in STEP 20, water supply (hot water supply) of the insufficient hot water amount calculated as described above is performed to the bathtub 1. That is, the controller 15 opens the solenoid valve 6 of the bath water supply passage 2a to open the gas burner 4 on the hot water supply heat exchanger 5 side in the same manner as in STEPs 1 and 8.
The hot water heated by the hot water supply heat exchanger 5 is supplied to the bathtub 1 via the circulation path 3 (hot water supply) while performing the combustion operation of (1). This water supply is performed until the integrated amount of the flow rate detected by the flow rate sensor 8 in the hot water supply path 2a for the bath reaches the above-mentioned insufficient hot water quantity. As a result, the hot water in the bathtub 1 reaches the target water level. Next, in STEP 21, the controller 15 executes a process of determining the presence or absence of residual water in the same manner as in STEPs 9 and 15, and further confirms the determination result in STEP 22. Then, at this time, if a determination result indicating that there is no remaining water is obtained, there is a possibility that hot water leaks from the bathtub 1 or the like.
5 outputs the error information to a not-shown display or the like (STEP 24), and then ends the test operation of the bath water heater.
Further, when the determination result that there is residual water is obtained in STEP 22, the controller 15 executes a process for performing the boiling operation of the hot water in the bathtub 1 in STEP 23, and then performs a test operation of the bath water heater. finish. The detailed description and illustration of the boiling operation are omitted here, but the outline is as follows. That is, the temperature of the hot and cold water in the bathtub 1 detected by the temperature sensor 14 is
When the temperature is lower than the target hot water temperature set in step 6, the combustion operation of the gas burner 9 on the side of the bath heat exchanger 10 is performed while circulating the hot water in the bathtub 1 through the circulation path 3 by the circulation pump 12. It is. And, by this combustion operation,
When the temperature of the hot water in the bathtub 1 detected by the temperature sensor 14 rises to the target hot water temperature, the combustion operation of the gas burner 9 and the operation of the circulation pump 12 are stopped, and the test operation of the bath water heater ends. When the hot water temperature of the bathtub 1 is substantially equal to the target hot water temperature at the start of the boiling operation, the test operation of the bath water heater ends without performing the combustion operation of the gas burner 9 or the like. . Next, an operation in a case where a normal automatic hot water operation is performed after the test operation of the bath water heater is performed as described above. After performing the trial operation of the bath water heater as described above,
When the operation mode of the automatic hot water operation mode is selected by the instruction 6 and the controller 15 is instructed to do so, the automatic hot water operation is performed by the control processing of the controller 15 as shown in the flowchart of FIG. First, STE
In P40, a predetermined amount (10 liters) of water is supplied to the circulation path 3 in the same manner as in STEP 1 in the test operation described above. At this time, it is sufficient that the water from the circulation port 1a of the circulation path 3 to the suction port side of the circulation pump 12 is substantially filled with water. It is also possible to set the amount according to the time Tm (the smaller the water flow OFF time Tm, the smaller the water supply amount), and supply the water at the set amount. Next, in STEP 41, the controller 15 performs a process of determining the presence / absence of residual water in the bathtub 1 in exactly the same manner as in STEPs 9, 15, and 21 in the test operation described above, and further confirms the determination result in STEP 42. At this time, if the determination result that there is residual water is obtained, that is, if there is already hot water equal to or higher than the water level of the circulation port 1a in the bathtub 1, the controller 15 determines
In STEP43, STEP2 in the above-mentioned trial run
The processing of the boiling operation is executed in exactly the same manner as in the case of 3.
Incidentally, after the process of the boiling operation, a later-described STEP will be described.
The processing from 48 is executed. Further, when the determination result that there is no residual water is obtained in STEP 42, the controller 15 supplies water in such a manner that the water level in the bathtub 1 becomes a water level raised by, for example, 5 cm from the reference water level in STEP 44. (Hot water supply) is performed on the bathtub 1. The amount of water supply in this case is determined by the STE in the test run described above.
In P13, the accumulated water supply amount stored and held (this is the water supply amount required for hot water to be supplied to the substantially empty bathtub 1 to the reference water level).
And the amount of water required to raise the water level by 5 cm from the reference water level (this is obtained from the cross-sectional area of the bathtub 1 calculated in STEP 18 in the test operation and the water level rise amount of 5 cm). Then, as in STEP 8 and the like in the test operation, the controller 15 opens the solenoid valve 6 of the bath water supply passage 2 a to perform the combustion operation of the gas burner 4 on the pre-hot water supply heat exchanger 5 side. The hot water heated by the hot water supply heat exchanger 5 is supplied to the bathtub 1 via the circulation path 3 (hot water supply). This water supply is performed until the integrated amount of the flow rate detected by the flow rate sensor 8 in the bath hot water supply passage 2a reaches the water supply amount obtained as described above. Next, in STEP 45, the controller 15 performs a process of determining the presence or absence of residual water in the bathtub 1 in exactly the same manner as in STEPs 9, 15, and 21.
The result of the determination is confirmed in TEP46. At this time, if a determination result indicating that there is no remaining water is obtained, there is a possibility that hot or cold water may leak from the drain port of the bathtub 1 or the like.
After outputting the error information to a not-shown display or the like (STEP 47), the controller 15 stops the automatic hot water operation. Further, when the determination result that there is residual water is obtained in STEP 46, or after the process of the boiling operation in STEP 42 is completed, the controller 15
In STEP 48, the current water level in the bathtub 1 is detected by the water level sensor 11. And this STEP4
After the processing of step 8, steps 19 to
Exactly the same processing as in STEP 24 is performed in STEPs 49 to 5
The process is performed in step 4, and the process of determining the hot water to the target water level, the presence / absence of residual water, and the process of boiling operation are performed. As described above, in the present embodiment, in the process of determining the presence or absence of residual water after measuring the water flow OFF time Tm corresponding to the length of the circulation path 3 in the test operation, the water level is determined after the operation of the circulation pump 12 is started. Remaining water presence / absence determination time Ta, T according to OFF time Tm
It is determined whether or not there is residual water in the bathtub 1 according to the ON / OFF state of the water flow switch 13 when b has elapsed. Therefore, as the circulation path 3 is shorter, the determination of the presence or absence of residual water can be performed in a shorter time. That is, it is possible to determine the presence / absence of residual water in a required short time corresponding to the length of the circulation path 3. The determination of the presence or absence of residual water is performed a plurality of times during the test operation or the normal hot water operation as described above. However, the determination of the presence or absence of the residual water is performed in a necessary short time as described above. Therefore, the time required for the operation can be shortened. Note that, in the embodiment described above, the water flow OF
Measurement of F time Tm (Steps 1 to 7 in FIG. 2)
However, the timing at which the measurement process of the water flow OFF time is performed is not limited to the above-described test operation, and may be performed, for example, during the first automatic hot water operation. The measurement process of the water flow OFF time Tm may be performed in a dedicated operation mode for measuring the water flow OFF time Tm. If the process of measuring the water flow OFF time is performed from the state in which the bathtub 1 is almost empty, the process of determining the presence or absence of residual water can be performed in a minimum necessary time regardless of the timing of the measurement process. it can. In the above embodiment, the water level sensor 11 for detecting the water level in the bathtub 1 has been described. However, for example, the combustion operation of the gas burner 9 is performed while the circulation pump 12 is operated. The amount of heat given to the water in the bathtub 1 is grasped from the calorific value of the gas burner 9 and the like, the temperature rise of the water in the bathtub 1 within the predetermined time is detected, and the amount of water in the bathtub 1 is grasped from the data. The present invention can be applied to such an apparatus (an apparatus having no water level sensor).

[Brief description of the drawings]

FIG. 1 is an overall system configuration diagram of an apparatus to which an embodiment of the present invention is applied.

FIG. 2 is a flowchart for explaining the operation of the apparatus shown in FIG. 1;

FIG. 3 is a flowchart for explaining the operation of the apparatus of FIG. 1;

FIG. 4 is a flowchart for explaining the operation of the apparatus of FIG. 1;

FIG. 5 is a flowchart for explaining the operation of the apparatus of FIG. 1;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Bathtub, 1a ... Circulation port, 2 ... Water supply channel, 3 ... Circulation channel, 1
2 ... circulation pump, 13 ... water flow switch (water flow detection means).

Claims (3)

[Claims] 1. A circulation path connected to a circulation port formed in a side wall of a bathtub and circulating hot and cold water in the bathtub by a circulation pump, water flow detection means for detecting the presence or absence of a water flow in the circulation path, and the circulation path. And a water supply passage connected to the circulation path so as to be able to supply water to the bath tub through the tub, based on the detection output of the water flow detection means in a state where the circulation pump is operated, the bath tub is provided with A method for determining whether or not there is residual water having a water level equal to or higher than the circulation port, wherein the bath tub is substantially empty, and at least a portion from the circulation port of the circulation path to the suction port of the circulation pump. A first step of supplying a predetermined amount of water from the water supply path to the circulation path so as to substantially fill the water, and then operating the circulation pump, and after starting the operation, the water flow detection means sets the circulation path to In A second step of measuring a time until it is detected that there is no water flow to flow, and determining whether there is residual water in the bathtub while operating the circulation pump after the second step. Determining the presence or absence of the residual water based on the detection output of the water flow detection means when the remaining water presence / absence determination time set according to the time detected in the second step has elapsed since the start of the operation of A method for determining the presence or absence of residual water in a bathtub. 2. The residual water presence / absence determination time corresponds to a first residual water presence / absence determination time corresponding to a case where it is determined that there is residual water in the bathtub and a case where it is determined that there is no residual water in the bathtub. 2. The method according to claim 1, wherein there is a second remaining water presence / absence determination time, and the first remaining water presence / absence determination time is set to a time longer than the second presence / absence determination time. . 3. The residual water presence / absence determination method according to claim 1, wherein the remaining water presence / absence determination time is set to a time equal to or longer than a predetermined lower limit.