Bathtub cleaning device

Abstract

To secure a high washing performance in a bathtub washing device in which hot water is supplied to a washing nozzle through a hot water injection pipe branching from a hot water supply pipe of a heat source machine.SOLUTION: In a process for continuously counting time elapsing from the opening of a hot water injection valve 46 in a process for injecting hot water to a bathtub 2 from a washing nozzle 25, determining whether a flow rate of the hot water detected by a flow rate sensor 47 is less than a predetermined determination flow rate for every time predetermined flow rate determination timing arrives from the opening of the hot water injection valve 46, and when the flow rate of the hot water detected by the flow rate sensor 47 at the flow rate determination timing is less than the determination flow rate, injecting the hot water to the bathtub 2 from the washing nozzle 25, predetermined extension time is added to valve opening setting time for opening the hot water injection valve 46.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a bathtub cleaning device, and more particularly to a bathtub cleaning device in which hot and cold water is supplied to a cleaning nozzle through a molten metal pouring pipe branching off from a hot water supply pipe of a heat source unit. [Background technology]

[0002] Conventionally, a bathtub cleaning device has been proposed in which a water supply pipe branched off from the hot water supply piping of a heat source unit such as a water heater is connected to a cleaning nozzle installed in the bathtub, and the supply of hot and cold water from the heat source unit to the cleaning nozzle is cut off by opening and closing a water supply valve installed in the water supply pipe, thereby performing a bathtub cleaning operation (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-79091 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the case where the hot water supply pipe branches off from the hot water supply pipe of the heat source machine as in the above Patent Document 1, when hot water is used from other faucets such as a faucet or shower during the bathtub cleaning operation, the flow rate of hot water supplied to the cleaning nozzle decreases due to a drop in water pressure. Therefore, even if hot water is sprayed from the cleaning nozzle for a certain period of time, it becomes impossible to spray the hot water to the desired position in the bathtub. It is possible to provide a flow control valve in the hot water supply pipe to increase or decrease the amount of hot water supplied to the cleaning nozzle depending on the amount of hot water used by the other faucets, but if the amount of hot water used by the other faucets is large, the flow rate of hot water supplied to the cleaning nozzle will be insufficient. As a result, dirt cannot be sufficiently removed, and there is a problem that cleaning performance is reduced.

[0005] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to ensure high cleaning performance in a bathtub cleaning device in which hot and cold water is supplied to a cleaning nozzle via a molten metal filling pipe branching off from the hot water supply piping of a heat source unit. [Means for solving the problem]

[0006] According to one aspect of the present invention, A hot water supply pipe that branches off from the hot water supply pipe of the heat source unit and supplies hot water to a cleaning nozzle installed in the bathtub; A pouring valve for opening and closing the flow path of the pouring pipe; A flow rate sensor that detects the flow rate of hot water flowing through the pouring pipe; A bathtub cleaning device comprising: a control device for executing a bathtub cleaning operation including a step of opening a hot water supply valve and spraying hot water from a cleaning nozzle into a bathtub, The control device continuously counts the elapsed time from when the hot water supply valve is opened during the process of spraying hot water from the cleaning nozzle into the bathtub, Each time a predetermined flow rate determination timing arrives after the hot water valve is opened, it is determined whether the flow rate of hot water detected by the flow rate sensor is less than a predetermined determination flow rate; A bathtub cleaning device is provided that has a control configuration that adds a predetermined extension time to the opening setting time for opening the hot water inlet valve in the process of spraying hot water from the cleaning nozzle into the bathtub when the flow rate of hot water detected by a flow rate sensor at the flow rate judgment timing is less than the judgment flow rate.

[0007] According to the bathtub cleaning device, since a flow sensor is provided in the hot water supply pipe, it is possible to detect a decrease in the flow rate of hot water supplied to the cleaning nozzle when another water faucet connected to the hot water supply pipe is opened during the bathtub cleaning operation. According to the bathtub cleaning device, during the process of spraying hot water from the cleaning nozzle into the bathtub, the elapsed time from the opening of the hot water supply valve is continuously counted, and if the flow rate of hot water detected by the flow sensor at the flow rate judgment timing is less than the judgment flow rate, an extension time is added to the opening setting time for opening the hot water supply valve, so that a spray time of hot water equal to or greater than the judgment flow rate can be secured. This makes it possible to suppress a decrease in cleaning performance due to the use of another water faucet. Note that the process of spraying hot water from the cleaning nozzle into the bathtub during the bathtub cleaning operation includes both a rinsing process in which only hot water is sprayed, and a cleaning process in which a cleaning liquid mixed with hot water and detergent is sprayed.

[0008] According to another aspect of the present invention, A hot water supply pipe that branches off from the hot water supply pipe of the heat source unit and supplies hot water to a cleaning nozzle installed in the bathtub; A pouring valve for opening and closing the flow path of the pouring pipe; A flow rate sensor that detects the flow rate of hot water flowing through the pouring pipe; A bathtub cleaning device comprising: a control device for executing a bathtub cleaning operation including a step of opening a hot water supply valve and spraying hot water from a cleaning nozzle into a bathtub, the control device, when the flow rate of hot and cold water detected by the flow sensor falls from equal to or greater than a predetermined judgment flow rate to less than the judgment flow rate, adds a predetermined extension time to a set valve open time for opening the hot water pouring valve in a process of spraying hot and cold water from the cleaning nozzle into the bathtub, and continues to count the elapsed time since the flow rate of hot and cold water fell below the judgment flow rate; Each time a predetermined flow rate determination timing arrives after the flow rate of hot and cold water has decreased below a determination flow rate, it is determined whether the flow rate of hot and cold water detected by the flow rate sensor is below a determination flow rate; There is provided a bathtub cleaning device having a control configuration that, if the flow rate of hot and cold water detected by a flow rate sensor at the flow rate determination timing is less than the determination flow rate, an extension time is further added to the valve open setting time.

[0009] According to the bathtub cleaning device, since a flow sensor is provided in the hot water supply pipe, it is possible to detect a decrease in the flow rate of hot water supplied to the cleaning nozzle when another water faucet connected to the hot water supply pipe is opened during the bathtub cleaning operation. However, since the other water faucet is used at any time regardless of the execution of the bathtub cleaning operation, if the hot water flow rate is not decreased at the flow rate judgment timing, there is a risk that the set valve open time will not be extended even if the hot water flow rate is decreased at a time other than the flow rate judgment timing.

[0010] However, with the bathtub cleaning device, when the hot and cold water flow rate falls from above the judgment flow rate to below the judgment flow rate, an extension time is added to the set valve open time, so that even if another faucet is used at any time, it is possible to reliably ensure a hot and cold water spray time above the judgment flow rate. Also, since a decrease in the hot and cold water flow rate is detected, it is considered that the use of another faucet has begun, and therefore by determining whether the hot and cold water flow rate is below the judgment flow rate each time the flow rate judgment timing arrives, the set valve open time can be appropriately extended according to the time by which the hot and cold water flow rate has decreased due to the use of the other faucet.

[0011] Preferably, in the bathtub cleaning device, The control device continuously monitors the flow rate of hot and cold water detected by the flow rate sensor during the process of spraying hot and cold water from the cleaning nozzle into the bathtub, A bathtub cleaning device is provided that has a control configuration that regulates the addition of an extension time to the valve opening setting time when the hot and cold water flow rate detected by a flow sensor recovers to above the judgment flow rate or falls below the judgment flow rate before the flow rate judgment timing arrives.

[0012] Since the amount of hot and cold water used by the other faucets is changed at any time regardless of the bathtub cleaning operation, the flow rate of hot and cold water detected by the flow sensor may recover to above the judgment flow rate within a short time, and then fall below the judgment flow rate. Therefore, if the flow rate of hot and cold water detected by the flow sensor is continuously monitored, adding an extension time to the set open time every time such hunting occurs within a short time will result in an excessively long set open time. However, according to the bathtub cleaning device, when the flow rate of hot and cold water detected by the flow sensor is continuously monitored, even if hunting occurs within a short time as described above before the flow rate judgment timing arrives, the addition of the extension time to the set open time is restricted, so the set open time can be extended without excess or deficiency.

[0013] Preferably, in the bathtub cleaning device, The extension time is set to be equal to or greater than the time interval between flow rate determination timings.

[0014] According to the bathtub cleaning device, the extension time is set to be equal to or greater than the time interval between the flow rate determination timings, so that the insufficient ejection time can be reliably made up for. Effect of the Invention

[0015] As described above, according to the present invention, high cleaning performance can be ensured in a bathtub cleaning device in which hot and cold water is supplied to a cleaning nozzle via a molten metal filling pipe branching off from the hot water supply piping of a heat source unit. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram showing an example of a bathtub cleaning system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a flowchart showing the basic steps of the bathtub cleaning operation according to the embodiment of the present invention. [Diagram 3] FIG. 3 shows an example of a control operation of the rinsing process in the bathtub cleaning operation according to the first embodiment of the present invention, where (a) shows a flowchart of the rinsing process and (b) shows a flowchart of the flow rate determination process. [Figure 4] FIG. 4 is a timing chart for explaining an example of a control operation of the rinsing process in the bathtub cleaning operation according to the first embodiment of the present invention. [Diagram 5] FIG. 5 shows an example of a control operation of the rinsing process in the bathtub cleaning operation according to the second embodiment of the present invention, and shows a flowchart of a rinsing process process and a flow rate determination process. [Figure 6] FIG. 6 is a timing chart for explaining an example of a control operation of the rinsing process in the bathtub cleaning operation according to the second embodiment of the present invention. [Figure 7] FIG. 7 shows an example of the control operation of the rinsing process in the bathtub cleaning operation according to the third embodiment of the present invention, where (a) shows a flowchart of the rinsing process processing, (b) shows a flowchart of the flow rate determination processing, and (c) shows a flowchart of the time addition invalid flag processing. [Figure 8] FIG. 8 is a timing chart for explaining an example of a control operation of the rinsing process in the bathtub cleaning operation according to the third embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, a bathtub cleaning system 1 configured using a bathtub cleaning device 4 according to an embodiment of the present invention is composed of a bathtub 2, a water heater 3 as a heat source machine that heats the bath water in the bathtub 2 or water supplied from the water supply, a bathtub cleaning device 4 that supplies the hot and cold water supplied from the water heater 3 to a cleaning nozzle 25 of the bathtub 2, and an operation terminal 5 that sets and instructs the operation of the water heater 3 and the bathtub cleaning device 4.

[0018] The water heater 3 includes a hot water burner 31A and a reheating burner 31B that can be turned on and off individually. The water heater 3 also includes a hot water heat exchanger 32A that recovers the combustion heat of the gas discharged from the hot water burner 31A and heats the water supplied from the waterworks through the water supply pipe 11, and a reheating heat exchanger 32B that recovers the combustion heat of the gas discharged from the reheating burner 31B and heats the bath water supplied from the bathtub 2 through the return pipe 13.

[0019] The water inlet of the hot water heat exchanger 32A is connected to the water supply pipe 11 via a hot water inlet pipe 33A. Meanwhile, the hot water outlet of the hot water heat exchanger 32A is connected to the hot water supply pipe 12 via a hot water outlet pipe 34A. The water supply pipe 11 is connected to the water supply system, and the hot water supply pipe 12 is connected to a hot water usage destination K of another faucet such as a faucet or shower.

[0020] The water inlet of the reheating heat exchanger 32B is connected to the return pipe 13 via a reheating water inlet pipe 33B. On the other hand, the hot water outlet of the reheating heat exchanger 32B is connected to the supply pipe 14 via a reheating water outlet pipe 34B.

[0021] Arranged in this order from upstream are a water supply volume sensor 35 for detecting the volume of water flowing from the water supply piping 11 to the hot water heat exchanger 32A and a diversion valve 36 for diverting the water supplied from the water supply piping 11 to the water inlet pipe 33A to the hot water outlet pipe 34A.

[0022] The hot water supply outlet pipe 34A branches off from the middle and is connected to the middle of the reheating outlet pipe 34B through the filling bypass pipe 30. The filling bypass pipe 30 is provided with a bypass opening / closing valve 39 that can block the flow of water from the hot water supply outlet pipe 34A to the reheating outlet pipe 34B.

[0023] The water heater 3 is equipped with a water heater control device 3A having a conventionally known circuit configuration that controls the operation of the water heater 3, such as a water heater operation that supplies hot water to hot water users K and the bathtub cleaning device 4, a water filling operation that supplies hot water to the bathtub 2, and a reheating operation that circulates and heats the bath water in the bathtub 2.

[0024] A bathtub fitting 23 is provided on the inner circumferential surface 21 of the bathtub 2, which serves as a water inlet for circulating the bath water in the bathtub 2 between the bathtub 2 and the water heater 3. A drain port 20 is provided at the bottom of the bathtub 2 for draining the bath water in the bathtub 2 and the hot and cold water sprayed into the bathtub 2 during the bathtub cleaning operation to the outside. A drain plug 24 is provided at the drain port 20, which can automatically close the drain port 20. A cleaning nozzle 25 is provided on the bottom surface 22 of the bathtub 2, which sprays the hot and cold water supplied from the bathtub cleaning device 4 towards the bathtub inner circumferential surface 21.

[0025] Bathtub fittings 23 are connected to heat exchanger 32B for reheating water heater 3 via return pipe 13 and forward pipe 14. Although not shown, bathtub fittings 23 are equipped with an intake port for introducing bath water in bathtub 2 into water heater 3 via return pipe 13, and an outlet port for directing bath water in bathtub 2 and hot water heated by water heater 3 into bathtub 2 via forward pipe 14.

[0026] Drain plug 24 is connected to a valve drive unit (not shown), and is configured to open and close automatically in response to instructions from a cleaning control device 4A built into bathtub cleaning device 4. By configuring bathtub cleaning system 1 using bathtub 2 equipped with drain plug 24 that can be opened and closed automatically in this way, it is possible to configure bathtub cleaning system 1 so that the water filling operation is automatically carried out after the bathtub cleaning operation has ended.

[0027] Hot water outlet pipe 41 of bathtub cleaning device 4 branches off and is connected to hot water supply pipe 12 connected to hot water usage destination K. Cleaning nozzle 25 is connected to hot water outlet pipe 41 of bathtub cleaning device 4 via cleaning pipe 15. Therefore, in this embodiment, hot water outlet pipe 41 and cleaning pipe 15 form a hot water supply pipe that branches off from hot water supply pipe 12 of water heater 3 and supplies hot water to cleaning nozzle 25.

[0028] Although not shown, cleaning nozzle 25 has an injection port that sprays hot water supplied from bathtub cleaning device 4 through cleaning piping 15 radially around the entire circumference of bathtub inner surface 21. The injection port is configured to spray hot water toward the upper area of ​​bathtub inner surface 21 as the flow rate of hot water per unit time supplied to cleaning nozzle 25 from cleaning piping 15 of bathtub cleaning device 4 increases, and to spray hot water toward the lower area of ​​bathtub inner surface 21 as the flow rate decreases.

[0029] Bathtub cleaning device 4 is equipped with detergent tank 40 capable of storing detergent, the above-mentioned cleaning pipe 15 and hot water outlet pipe 41, and detergent mixing pipe 42 that introduces the detergent in detergent tank 40 to hot water outlet pipe 41.

[0030] The detergent mixing pipe 42 has an upstream end connected to a detergent outlet of the detergent tank 40, and a downstream end connected to a junction 44 of the hot water outlet pipe 41 and the washing pipe 15. A detergent on-off valve 43 capable of blocking the discharge of detergent from the detergent tank 40 to the hot water outlet pipe 41 is disposed in the detergent mixing pipe 42. A float sensor 80 for detecting the amount of detergent is provided inside the detergent tank 40. The float sensor 80 is capable of floating and sinking in the vertical direction following the liquid level of the detergent in the detergent tank 40, and is configured to be turned on when the water level in the detergent tank 40 becomes higher than a predetermined water level and to be turned off when the water level becomes lower than the predetermined water level. An on / off detection signal of the float sensor 80 is output to the washing control device 4A.

[0031] Upstream of the junction 44 of the detergent mixing pipe 42 in the hot water outlet pipe 41, there are arranged in this order from downstream: a backflow prevention valve 45 for preventing backflow of detergent and hot water upstream of the hot water outlet pipe 41; a hot water inlet valve 46 that can cut off the supply of hot water from the hot water outlet pipe 41 to the cleaning pipe 15; a flow sensor 47 that detects the flow rate of hot water per unit time supplied from the hot water supply pipe 12 to the hot water outlet pipe 41; and a flow control valve 48 that can adjust the flow rate of hot water per unit time supplied from the hot water outlet pipe 41 to the cleaning pipe 15.

[0032] Junction 44 has a Venturi tube structure with a diameter that narrows approximately in the middle, and detergent mixing pipe 42 is connected to the narrowed portion of junction 44. Therefore, when detergent on-off valve 43 is open, detergent in detergent tank 40 is drawn into hot water outlet pipe 41 by negative pressure generated when hot water supplied to hot water outlet pipe 41 flows through the narrowed portion of junction 44, and is mixed with the hot water.

[0033] For example, when the flow rate of hot water supplied from outlet pipe 41 to cleaning nozzle 25 via cleaning pipe 15 is set to a predetermined set flow rate (e.g., 6 L / min), the opening is adjusted so that the flow rate detected by flow sensor 47 becomes the set flow rate. As a result, hot water is sprayed from cleaning nozzle 25 toward a predetermined range of bathtub inner surface 21.

[0034] Bathtub cleaning device 4 is equipped with a cleaning control device 4A that controls the operation of bathtub cleaning device 4, such as the bathtub cleaning operation in which hot and cold water supplied from water heater 3 is sprayed from cleaning nozzle 25 into bathtub 2. Although not shown, each element of bathtub cleaning device 40, such as detergent on-off valve 43, hot water supply valve 46, flow rate adjustment valve 48, flow rate sensor 47, float sensor 80, etc., is connected to cleaning control device 4A via electrical wiring.

[0035] The washing control device 4A is an electronic circuit unit including a microcomputer, memory, etc., and includes an operation determination unit that monitors the operating state of the operation terminal 5, a spray amount control unit that opens and closes the hot water supply valve 46 and adjusts the opening degree of the flow rate adjustment valve 48, a detergent amount control unit that opens and closes the detergent on-off valve 43, a drain control unit that opens and closes the drain plug 24, a flow rate monitoring and determination unit that monitors the flow rate of hot and cold water detected by the flow rate sensor 47 during the washing process and rinsing process and determines whether it is equal to or greater than a predetermined determination flow rate, and a flow rate monitoring and determination unit that determines whether or not the flow rate of hot and cold water detected by the flow rate monitoring and determination unit is equal to or greater than a predetermined determination flow rate under certain conditions, which will be described later. The circuit configuration includes an extension time adding section which adds a predetermined extension time to the set open time of the hot water supply valve 46 in the process and updates it, an open time determining section which determines whether the set open time is equal to or greater than the maximum open time, a timing section which measures predetermined times such as standby times in each process, and a memory section which stores the standby times in each process, the predetermined set flow rates and determined flow rates in the cleaning process and rinsing process, the initial set open time of the hot water supply valve 46 when hot water is sprayed from the cleaning nozzle 25 at a predetermined set flow rate, the extension time to be added to the set open time, the maximum open time, etc. These data can be obtained in advance by experimentation based on the shape and size of the bathtub 2, the configuration of the water heater 3 and bathtub cleaning device 4, etc. The cleaning control device 4A also includes a circuit configuration including an execution section which executes each process of the bathtub cleaning operation.

[0036] The operation terminal 5 is equipped with an operation switch 50 for the bathtub cleaning system 1, a water filling switch 51 that instructs the start of a water filling operation, a reheating switch 52 that instructs the start of a reheating operation, a bathtub cleaning switch 53 that instructs the start of a bathtub cleaning operation, an adjustment switch 54 for adjusting settings such as the hot water temperature, amount of water filling, and number of cleanings, a display unit 55 that displays operating conditions such as the set hot water temperature and amount of water filling, and an audio output unit 56 that alerts by audio when the hot water filling operation or bathtub cleaning operation has ended, and is connected by wire or wirelessly to the respective control devices of the water heater 3 and the bathtub cleaning device 4 (hot water supply control device 3A, cleaning control device 4A).

[0037] FIG. 2 shows the basic steps of the bathtub cleaning operation performed by the bathtub cleaning device according to this embodiment. To give an overview of each step, when the bathtub cleaning switch 53 is turned on, the draining step is first performed (step S1). In the draining step, the drain plug 24 of the bathtub 2 is opened, and the bath water in the bathtub 2 is drained to the outside. Next, when a predetermined drainage waiting time has elapsed since the drain plug 24 was opened, the process moves to the preliminary rinsing step (step S2). In the preliminary rinsing step, the hot water supply valve 46 is opened, and the opening degree of the flow rate adjustment valve 48 is adjusted so that the flow rate of hot water detected by the flow rate sensor 47 becomes the set flow rate for rinsing. In addition, when the water flow rate detected by the water supply amount sensor 35 becomes equal to or greater than a predetermined water amount, the water heater 3 starts heating the water, and the hot water heated and generated by the hot water heat exchanger 32A is introduced into the hot water outlet pipe 41 of the bathtub cleaning device 4 through the hot water supply pipe 12, and the hot water is sprayed from the cleaning nozzle 25 into the bathtub 2. When the predetermined valve opening time for pre-rinsing has elapsed, the hot water supply valve 46 is closed. When a predetermined waiting time before washing has elapsed since the hot water supply valve 46 was closed, the process proceeds to the washing process (step S3). In the washing process, the hot water supply valve 46 is opened, and the opening of the flow rate control valve 48 is adjusted so that the flow rate of hot water detected by the flow rate sensor 47 becomes the set flow rate for washing, and the detergent opening / closing valve 43 is also opened. As a result, a washing liquid obtained by mixing hot water supplied from the hot water outlet pipe 41 and detergent supplied from the detergent mixing pipe 42 is sprayed from the washing nozzle 25 into the bathtub 2. When the predetermined valve opening time for washing has elapsed, the hot water supply valve 46 and the detergent opening / closing valve 43 are closed, and when a predetermined waiting time before rinsing has elapsed since the hot water supply valve 46 and the detergent opening / closing valve 43 were closed, the process proceeds to the rinsing process (step S4). In the rinsing step, as in the pre-rinsing step described above, hot water supply valve 46 is opened, the opening of flow control valve 48 is adjusted so that the flow rate of hot water detected by flow sensor 47 becomes the set flow rate for rinsing, and hot water is sprayed from cleaning nozzle 25 into bathtub 2 for a predetermined set valve opening time for rinsing. Each step may be repeated multiple times, and the spraying of cleaning liquid in the cleaning step and the spraying of hot water in the rinsing step may be repeated multiple times at regular time intervals.Although not shown, if the bathtub filling operation is set to be automatically performed subsequently after the bathtub cleaning operation is completed, the drain plug 24 is closed and the bathtub filling operation is performed after the bathtub cleaning operation is completed.

[0038] Next, an example will be given to explain the control operation of bathtub cleaning device 4 when the flow rate of hot and cold water supplied to cleaning nozzle 25 fluctuates due to the use of another faucet. Below, the control operation in the rinsing process will be explained, but the same applies to the control operation in the pre-rinsing process and the cleaning process.

[0039] Example 1 FIG. 3 is a flow chart showing an example of the control operation in the rinsing process of this embodiment, and FIG. 4 is a timing chart showing an example of the correlation between the elapsed time in the rinsing process and the flow rate of hot and cold water. As described above, when the rinsing process is started, the hot water supply valve 46 is opened (step S101 in FIG. 3(a)). When the hot water supply valve 46 is opened, the rinse timer and the flow rate determination timer for measuring the set valve opening time are started to count (step S102 in FIG. 3(a)). The rinse timer continues to count until the rinsing process is completed. When a predetermined time has elapsed in the flow rate determination timer and a predetermined flow rate determination timing (e.g., every 5 seconds) arrives (Yes in step S103 in FIG. 3(a), (A) in FIG. 4), the flow rate determination process is executed (step S104 in FIG. 3(a)).

[0040] In this flow rate determination process, it is determined whether the flow rate of hot and cold water detected by flow rate sensor 47 is less than a predetermined determination flow rate (e.g., 4.8 L / min) (step S111 in FIG. 3(b)). If the flow rate of hot and cold water is equal to or greater than the determination flow rate (No in step S111 in FIG. 3(b)), the initial valve open setting time that has been set (e.g., 90 seconds) is maintained. The determination flow rate may be the same as the set flow rate for rinsing, or may be a flow rate less than the set flow rate that provides a certain level of cleaning effect.

[0041] The flow rate determination process is executed continuously during the rinsing step. When the flow rate determination timing arrives, if the flow rate of hot and cold water is less than the determination flow rate (Yes in step S111 of FIG. 3(b), (B)(C) of FIG. 4), it is determined whether the set valve open time exceeds the maximum valve open time (e.g., four times the initial valve open time) (step S112 of FIG. 3(b)). If the set valve open time is less than the maximum valve open time (Yes in step S112 of FIG. 3(b)), a predetermined extension time (e.g., 5 seconds) is added to the valve open time to update and set it (step S113 of FIG. 3(b)). Note that if the set valve open time exceeds the maximum valve open time (No in step S112 of FIG. 3(b)), the set valve open time is maintained.

[0042] As described above, each time the flow rate judgment timing arrives, it is judged whether the flow rate of hot and cold water is less than the judgment flow rate, and when the rinse timer reaches the set valve opening time, the hot water inlet valve 46 is closed to end the rinsing process (steps S105 to S106 in Figure 3(a)).

[0043] As described above, according to this embodiment, the time elapsed since the hot water supply valve 46 was opened is continuously counted during the rinsing process, and if the flow rate of hot water detected by the flow rate sensor 47 at the flow rate judgment timing is less than the judgment flow rate, an extension time is added to the set valve opening time for opening the hot water supply valve 46 during the rinsing process, so that a hot water spray time equal to or greater than the judgment flow rate can be ensured. In addition, since the extension time is set to the same time as the time interval between the flow rate judgment timings, it is possible to reliably cover any shortfall in spray time. This makes it possible to suppress a decrease in cleaning performance due to the use of another faucet.

[0044] In this embodiment, if the flow rate of hot and cold water at the flow rate determination timing is less than the determined flow rate, an extension time is added to the open valve set time. However, it is also possible to count the number of flow rate shortages at the flow rate determination timing, and add a total extension time according to the number of flow rate shortages as a predetermined extension time at the end of the initial open valve set time. Also, if the flow rate of hot and cold water that is less than the determined flow rate at the flow rate determination timing is detected a predetermined number of times or more, a flow rate abnormality error may be notified. Furthermore, although the extension time added to the open valve set time is set to the same time as the time interval between flow rate determination timings, it may be shorter than the time interval between flow rate determination timings (e.g., 2 seconds) or longer than the time interval between flow rate determination timings (e.g., 10 seconds).

[0045] Example 2 This embodiment differs from embodiment 1 in that when the hot and cold water flow rate is equal to or greater than the judgment flow rate, the hot and cold water flow rate is continuously monitored, and when the hot and cold water flow rate decreases from equal to or greater than the judgment flow rate to less than the judgment flow rate, an extension time is added to the opening valve set time, and in that when the hot and cold water flow rate decreases below the judgment flow rate and the flow rate judgment timing arrives, if the hot and cold water flow rate is less than the judgment flow rate, an extension time is further added to the opening valve set time.

[0046] FIG. 5 is a flow chart showing an example of a control operation in the rinsing process of this embodiment, and FIG. 6 is a timing chart showing an example of a correlation between the elapsed time in the rinsing process and the flow rate of hot and cold water.

[0047] When the rinsing process is started and the hot water supply valve 46 is opened, the rinsing timer starts counting (steps S201 to S202 in FIG. 4). In this embodiment, the rinsing timer continues counting until the rinsing process is completed. If the valve opening time has not elapsed (No in step S203 in FIG. 4), the flow rate of hot and cold water continues to be monitored until the flow rate of hot and cold water decreases from a predetermined judgment flow rate (e.g., 4.8 L / min) or more to less than the judgment flow rate (step S211 in FIG. 4).

[0048] After the rinsing step has started, when the flow rate of hot and cold water decreases from equal to or greater than the determination flow rate to less than the determination flow rate (Yes in step S211 of FIG. 5, (A) of FIG. 6), if the set valve open time is less than the maximum valve open time, a predetermined extension time (e.g., 5 seconds) is added to the set valve open time, the set valve open time is updated and set, and the flow rate determination timer starts counting (steps S212 to S214 of FIG. 5). Note that if the set valve open time exceeds the maximum valve open time (No in step S212 of FIG. 5), the set valve open time is maintained.

[0049] Next, if the set valve open time has not yet been reached (No in step S219), each time a flow rate determination timing (for example, every 5 seconds) arrives, it is determined whether the flow rate of hot and cold water is less than the determination flow rate (steps S215 to S216 in FIG. 5). If the flow rate of hot and cold water is less than the determination flow rate when the flow rate determination timing arrives (Yes in step S216 in FIG. 5, (B) in FIG. 6), and if the set valve open time is less than the maximum valve open time (Yes in step S217 in FIG. 5), the extension time is further added to the set valve open time to update and set it (step S218 in FIG. 5). Note that if the set valve open time exceeds the maximum valve open time (No in step S217 in FIG. 5), the set valve open time is maintained.

[0050] On the other hand, if the hot and cold water flow rate has recovered to above the judgment flow rate at the flow rate judgment timing (No in step S216 in FIG. 5, (C) in FIG. 6), the set open valve setting time is maintained and the hot and cold water flow rate is continuously monitored. Then, if the hot and cold water flow rate falls below the judgment flow rate again (Yes in step S211 in FIG. 5, (D) in FIG. 6), an extension time is added to the open valve setting time as described above, and a new count of the flow rate judgment timer is started (steps S213 to S214 in FIG. 5). When the rinse timer reaches the set open valve setting time, the hot water supply valve 46 is closed and the rinsing process is ended (steps S203 to S204 in FIG. 5).

[0051] Since the use of the other faucet is performed at any time regardless of the execution of the bathtub cleaning operation, if the flow rate of hot and cold water is not decreased at the flow rate judgment timing, the set valve open time may not be extended even if the flow rate of hot and cold water is decreased at a time other than the flow rate judgment timing. However, according to the bathtub cleaning device described above, when the flow rate of hot and cold water detected by the flow rate sensor 47 is equal to or greater than the predetermined judgment flow rate, the flow rate of hot and cold water is continuously monitored, and when the flow rate of hot and cold water decreases from equal to or greater than the judgment flow rate to less than the judgment flow rate, an extension time is added to the set valve open time, so that even if the other faucet is used at any time, the injection time of hot and cold water equal to or greater than the judgment flow rate can be reliably secured. Furthermore, since it is considered that the use of the other faucet has started if a decrease in the flow rate of hot and cold water is detected, the set valve open time can be appropriately extended according to the time by which the flow rate of hot and cold water has decreased due to the use of the other faucet by determining whether the flow rate of hot and cold water is less than the judgment flow rate each time the flow rate judgment timing arrives.

[0052] Furthermore, according to the bathtub cleaning device, when the flow rate of hot and cold water drops from above the judgment flow rate to below the judgment flow rate, an extension time is added to the set open valve time. Therefore, even if the flow rate of hot and cold water has recovered to above the judgment flow rate when the flow rate judgment timing arrives, if the flow rate of hot and cold water drops below the judgment flow rate again, an extension time is further added to the set open valve time. Therefore, the set open valve time can be extended within a short time after the use of the other faucet is resumed. Furthermore, since the extension time added to the set open valve time is set to the same time as the time interval between the flow rate judgment timings, the set open valve time can be optimized without excess or deficiency. The extension time may be shorter than the time interval between the flow rate judgment timings (for example, 2 seconds) or longer than the time interval between the flow rate judgment timings (for example, 10 seconds).

[0053] Example 3 This embodiment differs from embodiment 2 in that the flow rate of hot and cold water is continuously monitored, and if the flow rate of hot and cold water recovers above the judgment flow rate before the flow rate judgment timing arrives, and then decreases below the judgment flow rate, the addition of extension time to the open valve setting time is regulated.

[0054] FIG. 7 is a flow chart showing an example of the control operation in the rinsing process of this embodiment, and FIG. 8 is a timing chart showing an example of the correlation between the elapsed time in the rinsing process and the flow rate of hot and cold water.

[0055] When the rinsing process is started and the hot water supply valve 46 is opened, a rinsing timer begins counting to measure the set valve open time (steps S301 to S302 in FIG. 7(a)). In this embodiment, the rinsing timer continues counting until the rinsing process is completed. Then, if the set valve open time has not elapsed (No in step S303 in FIG. 7(a)), a flow rate determination process is executed (step S304 in FIG. 7(a)).

[0056] In the flow rate determination process, the hot and cold water flow rates are continuously monitored, and when the hot and cold water flow rate falls from above a predetermined determination flow rate (e.g., 4.8 L / min) to below the determination flow rate (Yes in step S311 in FIG. 7(b), (A) in FIG. 8), it is determined whether the timer addition disable flag is "OFF" (step S312 in FIG. 7(b)). The timer addition disable flag is information that indicates whether or not to restrict the addition of a predetermined extension time (e.g., 5 seconds) to the open valve set time.

[0057] If the timer addition disable flag is “OFF” (Yes in step S312 in FIG. 7(b)), and if the set valve open time is less than the maximum valve open time (Yes in step S313 in FIG. 7(b)), the extension time is added to the set valve open time to update and set the valve open time (step S314 in FIG. 7(b)).

[0058] When the extension time is added to the valve open set time, timer addition invalid flag processing is executed (step S315 in FIG. 7(b)). In the timer addition invalid flag processing, first, the timer addition invalid flag is changed from "OFF" to "ON" (step S321 in FIG. 7(c)). Next, the invalid timer starts counting (step S322 in FIG. 7(c)). When the invalid timer count has elapsed a predetermined extended addition invalid time (e.g., 5 seconds) (Yes in step S323 in FIG. 7(c)), the timer addition invalid flag is changed from "ON" to "OFF" (step S324 in FIG. 7(c)).

[0059] In the flow rate determination process, the hot and cold water flow rate is continuously monitored, and when the extended addition invalid time has elapsed, the timer addition invalid flag is changed to "OFF" (Yes in step S312 in Figure 7(b)), so if the hot and cold water flow rate when the extended addition invalid time has elapsed is less than the determined flow rate (Yes in step S311, Figure 8(B)), and if the set valve opening time is less than the maximum valve opening time (Yes in step S313 in Figure 7(b)), the extended time is added to the set valve opening time, and the valve opening time is updated and set (step S314 in Figure 7(b)). Therefore, if the hot and cold water flow rate continues to decrease, the extended time is added to the valve opening time each time the extended addition invalid time, which is the flow rate determination timing, elapses, as in Example 2.

[0060] On the other hand, when the extended addition invalid time has elapsed (i.e., when the flow rate judgment timing arrives), if the hot and cold water flow rate has recovered to above the judgment flow rate (No in step S311 of FIG. 7(b), (C) of FIG. 8), the timer addition invalid flag is maintained at "OFF". Therefore, if the hot and cold water flow rate falls below the judgment flow rate again (Yes in step S311 of FIG. 7(b), (D) of FIG. 8), similarly to the above, if the set valve open time is less than the maximum valve open time (Yes in step S313 of FIG. 7(b)), the extended time is further added to the set valve open time, the set valve open time is updated and set, and the timer addition invalid flag process is executed (steps S314 to S315 of FIG. 7(b)). In other words, if the timer addition invalid flag is "OFF", and the set valve open time is less than the maximum valve open time, the extended time is added to the set valve open time each time the hot and cold water flow rate falls from above the judgment flow rate to below the judgment flow rate.

[0061] During the flow rate determination process, the hot and cold water flow rates are continuously monitored, so hunting may occur within a short period of time where the hot and cold water flow rate recovers above the determined flow rate and then falls below the determined flow rate. However, if the extended addition invalid time has not elapsed (i.e., the flow rate determination timing has not arrived), the timer addition invalid flag is "ON" (No in step S323 of Figure 7(c), Yes in step S311 of Figure 7(b), No in step S312, Figure 8(E)), so the extended time is not added to the set valve opening time. When the rinse timer reaches the set valve opening time, the hot water inlet valve 46 is closed and the rinse process is ended (steps S303 and S305 of Figure 7(a)).

[0062] Because the amount of hot and cold water used by the other faucets is changed at any time regardless of the bathtub cleaning operation, the flow rate of hot and cold water detected by the flow rate sensor 47 may recover to above the judgment flow rate within a short time, and then fall below the judgment flow rate. Even if such hunting occurs within a short time, it has little effect on the cleaning performance, but if the flow rate of hot and cold water is continuously monitored, adding an extension time to the set open time each time hunting occurs will make the set open time excessively long. However, according to the bathtub cleaning device, when the flow rate of hot and cold water is continuously monitored, even if the flow rate of hot and cold water detected by the flow rate sensor 47 recovers to above the judgment flow rate and falls below the judgment flow rate before the flow rate judgment timing arrives, the addition of the extension time to the set open time is restricted, so the set open time can be extended without excess or deficiency.

[0063] In addition, the extension time added to the valve-open setting time is set to the same time as the time interval between the flow rate determination timings, so that the valve-open setting time can be optimized without excess or deficiency. Note that the extension time may be shorter than the time interval between the flow rate determination timings (e.g., 2 seconds) or longer than the time interval between the flow rate determination timings (e.g., 10 seconds). [Explanation of symbols]

[0064] 3. Water heater 4 Bathtub cleaning device 12 Hot water piping 15 Cleaning piping 40 Detergent tank 41 Hot water outlet pipe 46 Hot water valve 47 Flow Sensor 4A Cleaning control device

Claims

1. A hot water supply pipe that branches off from the hot water supply pipe of the heat source unit and supplies hot water to a cleaning nozzle installed in the bathtub; A pouring valve for opening and closing the flow path of the pouring pipe; A flow rate sensor that detects the flow rate of hot water flowing through the pouring pipe; A bathtub cleaning device comprising: a control device for executing a bathtub cleaning operation including a process of opening a hot water supply valve and spraying hot water from a cleaning nozzle into a bathtub, the control device, when the flow rate of hot and cold water detected by the flow sensor falls from equal to or greater than a predetermined judgment flow rate to less than the judgment flow rate, adds a predetermined extension time to a set valve open time for opening the hot water pouring valve in a process of spraying hot and cold water from the cleaning nozzle into the bathtub, and continues to count the elapsed time since the flow rate of hot and cold water fell below the judgment flow rate; Each time a predetermined flow rate determination timing arrives after the flow rate of hot and cold water has decreased below a determination flow rate, it is determined whether the flow rate of hot and cold water detected by the flow rate sensor is below a determination flow rate; A bathtub cleaning device having a control configuration that adds an extension time to the valve opening setting time if the flow rate of hot and cold water detected by a flow sensor at the flow rate determination timing is less than the determination flow rate.

2. The bathtub cleaning device according to claim 1, The control device continuously monitors the flow rate of hot and cold water detected by the flow rate sensor during the process of spraying hot and cold water from the cleaning nozzle into the bathtub, A bathtub cleaning device having a control configuration that, when the flow rate of hot and cold water detected by a flow sensor at a flow rate determination timing is less than the determined flow rate and further extension time is added to the open valve set time, and then the flow rate of hot and cold water detected by the flow sensor recovers to above the determined flow rate and then decreases to below the determined flow rate before the next flow rate determination timing arrives, regulates the addition of extension time to the open valve set time to which further extension time has been added based on the decrease.

3. In the bathtub cleaning device according to claim 1 or 2, The control device continuously monitors the flow rate of hot and cold water detected by the flow rate sensor during the process of spraying hot and cold water from the cleaning nozzle into the bathtub, After the hot and cold water flow rate falls below the judgment flow rate from above the judgment flow rate and the extension time is added to the opening valve setting time, the hot and cold water flow rate detected by the flow sensor is judged before the next flow rate judgment timing arrives. A bathtub cleaning device having a control configuration that, when the flow rate recovers to above a constant flow rate or decreases to below a judgment flow rate, restricts the addition of an extension time to the open valve set time to which an extension time has been added based on the decrease.

4. The bathtub cleaning device according to any one of claims 1 to 3, In this bathtub cleaning device, the extension time is set to be equal to or greater than the time interval between flow rate determination timings.

Images