Bathtub cleaning device

Abstract

To provide a bathtub washing device capable of reducing a load applied to a detergent valve when opening and closing the detergent valve.SOLUTION: A bathtub washing device (10) includes: a washing nozzle (5) disposed in a bathtub; a hot water pooling part (15) for pooling hot water; a hot water passage (14) for connecting the hot water pooling part (15) and the washing nozzle (5); a pump (16) interposed in the hot water passage (14); a detergent mixing part (17) interposed in the hot water passage (14) between the pump (16) and the washing nozzle (5); a detergent valve (7b) that is opened and closed for switching supply and stop of detergent for the detergent mixing part (17); and a control part (20) for controlling injection, from the washing nozzle (5), of washing liquid generated by mixing hot water fed into the hot water passage (14) toward the washing nozzle (5) by driving the pump (16) with the detergent at the detergent mixing part (17). When stopping injection of the washing liquid, the control part (20) closes the detergent valve (7b) after a preset delay time passes from the issuance of a stop command for the pump (16).SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a bathtub cleaning device that automatically cleans a bathtub, and in particular to a bathtub cleaning device equipped with a hot water storage section that stores hot water so as to be able to accommodate low water supply pressure. [Background technology]

[0002] Bathtub cleaning devices that automatically clean bathtubs have been used for some time now. Bathtub cleaning devices clean the bathtub by spraying a cleaning liquid into the bathtub to loosen dirt adhering to the bathtub and then spraying hot and cold water to wash it away.

[0003] For example, Patent Document 1 discloses a bathtub cleaning device that opens a hot water supply valve, mixes detergent in a venturi detergent mixer with hot water flowing due to the clean water supply pressure, produces cleaning liquid, and sprays this cleaning liquid from a cleaning nozzle. This bathtub cleaning device is configured to spray cleaning liquid multiple times while cleaning the bathtub, and describes that the detergent valve is opened before the hot water supply valve is opened when spraying of the cleaning liquid starts, so as not to wash away cleaning liquid that has adhered to the bathtub from the previous spray with hot water.

[0004] Also, as in Patent Document 2, a bathtub cleaning device is known that performs a preliminary rinsing step in which hot and cold water is sprayed using hot and cold water flowing due to the supply pressure of clean water before the cleaning liquid spraying step, and at the end of the preliminary rinsing step, opens the detergent valve to prepare cleaning liquid in the hot and cold water passage to the cleaning nozzle. This makes it possible to spray cleaning liquid immediately in the cleaning liquid spraying step. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-146746 A [Patent Document 2] JP 2018-50649 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in areas or buildings where the water supply pressure is low, it may be difficult to spray cleaning liquid and hot and cold water with sufficient force from the cleaning nozzle with the bathtub cleaning devices of Patent Documents 1 and 2. To deal with cases where the water supply pressure is low, a bathtub cleaning device is known that is configured to supply hot and cold water stored in a hot and cold water storage section to the cleaning nozzle by driving a pump, and spray the cleaning liquid generated by opening the hot and cold water and detergent valves.

[0007] When stopping the spray of cleaning liquid, this type of bathtub cleaning device stops the pump and closes the detergent valve. At this time, if the detergent valve is, for example, a solenoid valve, it can close the detergent valve instantly. On the other hand, even if a stop command is issued to the pump, it does not stop instantly due to inertia. Therefore, since hot water flows with the detergent valve closed, the detergent mixing section side, which is downstream of the detergent valve, becomes negative pressure compared to the upstream side of the detergent valve. As a result, a force pulling toward the detergent mixing section acts on the valve body of the detergent valve, placing a load on the detergent valve.

[0008] On the other hand, when starting to spray the cleaning liquid, the pump is driven and the detergent valve is opened. When the pump is driven, hot and cold water flows, and the detergent mixing section side of the detergent valve is put under negative pressure, and the detergent valve is opened by moving the valve body against the force pulling it toward the detergent mixing section, which places a load on the detergent valve.

[0009] Here, the valve body of the detergent valve is often made of an elastic material such as rubber that can fit closely to the valve seat while absorbing tolerances, etc. When cleaning the bathtub, the spraying and stopping of the cleaning liquid is repeated, so the force pulling it toward the detergent mixing section repeatedly acts on the valve body, causing it to deform, and there is a risk that the durability of the detergent valve will be impaired.

[0010] An object of the present invention is to provide a bathtub cleaning device that can reduce the load on the detergent valve when opening and closing the detergent valve. [Means for solving the problem]

[0011] The bathtub cleaning device of the invention of claim 1 comprises a cleaning nozzle arranged in a bathtub, a hot and cold water storage section for storing hot and cold water, a hot and cold water passage connecting the hot and cold water storage section to the cleaning nozzle, a pump interposed in the hot and cold water passage, a detergent mixing section interposed in the hot and cold water passage between the pump and the cleaning nozzle, a detergent valve that opens and closes to switch between supplying and stopping detergent to the detergent mixing section, and a control section that drives the pump and controls the spraying from the cleaning nozzle of cleaning liquid produced by mixing detergent in the detergent mixing section with hot and cold water sent into the hot and cold water passage toward the cleaning nozzle, wherein the control section, when stopping the spraying of the cleaning liquid, closes the detergent valve a predetermined delay time after issuing a command to stop the pump.

[0012] According to the above configuration, the bathtub cleaning device opens the detergent valve to supply hot and cold water to the cleaning nozzle by driving the pump, generates cleaning liquid mixed with detergent in the detergent mixing section, and sprays this cleaning liquid from the cleaning nozzle. When spraying cleaning liquid is to be stopped, the detergent valve is kept open until a preset delay time has elapsed since a command to stop the pump has been issued, and then the detergent valve is closed after the delay time has elapsed. The pump rotation speed has decreased or the pump has stopped before the delay time has elapsed, and the negative pressure on the detergent mixing section side of the detergent valve has become small or has been eliminated, so that the detergent valve is closed in a state in which the force pulling the detergent mixing section side is weakened or not working, thereby reducing the load on the detergent valve when spraying cleaning liquid is stopped.

[0013] The bathtub cleaning device of the invention of claim 2 is the invention of claim 1, configured so that the cleaning liquid is sprayed multiple times, and the control unit, when starting at least the second or subsequent sprays of the cleaning liquid, opens the detergent valve with the pump stopped, and issues a command to drive the pump in a state where detergent can be supplied to the detergent mixing unit. According to the above configuration, the detergent valve is opened without any pulling force acting on the detergent mixing section, so the load on the detergent valve when starting to spray the cleaning liquid can be reduced. Also, since the pump can be driven to mix the detergent from the start of the hot and cold water flow, it is possible to avoid washing away the cleaning liquid sprayed previously with hot and cold water.

[0014] The bathtub cleaning device of the invention of claim 3 is characterized in that, in the invention of claim 1 or 2, the control unit issues the stop command after lowering the set rotational speed of the pump to a predetermined stop preparation rotational speed. With the above configuration, a pump stop command is issued when the set rotational speed of the pump is reduced to the stop preparation rotational speed and the force pulling the detergent mixing section toward the detergent mixing section is weakened or not acting, and the detergent valve is closed after a set delay time has elapsed since the pump stop command. Therefore, the detergent valve can be closed reliably without any force pulling the detergent mixing section toward the detergent mixing section, thereby reducing the load on the detergent valve when spraying of the cleaning liquid is stopped. Effect of the Invention

[0015] According to the bathtub cleaning device of the present invention, the load applied to the detergent valve when opening and closing the detergent valve can be reduced, thereby improving the durability of the detergent valve. [Brief description of the drawings]

[0016] [Figure 1] 1 is a configuration diagram of a bathtub cleaning device according to an embodiment of the present invention. [Diagram 2] 4 is a flowchart of a bathtub cleaning operation by the bathtub cleaning device according to the embodiment. [Diagram 3] 11 is a flowchart of solenoid valve control during bathtub cleaning operation. [Figure 4] 13 is an example of a time chart for spraying cleaning liquid in a bathtub cleaning operation. [Diagram 5] 5 is a time chart showing a modification of the time when the cleaning liquid jet in FIG. 4 is stopped. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, the mode for carrying out the present invention will be described based on examples. EXAMPLES

[0018] First, the overall configuration of the bathtub cleaning device 10 of the present invention, including peripheral equipment, will be described with reference to Figure 1. To fill and reheat the bathtub 1, the bathtub 1 and hot water supply device 2 are connected via a filling / reheating passage 3 and a circulation adapter 1a. Also, at the bottom of the bathtub 1, there are disposed a drain plug 4, for example an electric type, for draining hot and cold water as shown by arrow D, and a cleaning nozzle 5 for spraying (spraying) hot and cold water and cleaning solution to clean the bathtub 1.

[0019] Near the bathtub 1 are provided a supply unit 6 that supplies hot water and cleaning liquid to the cleaning nozzle 5, a detergent tank 7 that stores the detergent to be supplied to the supply unit 6, and a drain switch 8 for opening and closing the drain plug 4. A hot water supply passage 2a for supplying hot water from the hot water supply device 2 is connected to the supply unit 6.

[0020] Furthermore, a power supply communication unit 9, which is disposed, for example, above the ceiling of the bathroom, is connected to the supply unit 6 so as to be able to supply power to and communicate with the supply unit 6. This power supply communication unit 9 is equipped with a control unit 20 that controls the bathtub cleaning operation, etc., of the bathtub cleaning device 10. The bathtub cleaning device 10 is made up of a cleaning nozzle 5, supply unit 6, detergent tank 7, drain switch 8, drain plug 4, power supply communication unit 9 (control unit 20), etc.

[0021] The water heater 2 is a combustion type water heater that uses, for example, the heat of combustion of fuel to heat clean water indicated by arrow W and supply it through the hot water passage 2a. When hot water use is started by starting the bathtub cleaning operation of the bathtub cleaning device 10 or by opening the hot water tap F, the flow of hot water in the water heater 2 is detected and the hot water supply operation is started. When hot water use is ended by ending the bathtub cleaning operation or by closing the hot water tap F, the stop of the flow of hot water in the water heater 2 is detected and the hot water supply operation is ended. The water heater 2 may be a water heater having another heat source unit, such as a heat pump type heat source unit.

[0022] A bathroom remote control 11 and a kitchen remote control 12 are communicatively connected to water heating device 2 for starting operations such as filling bathtub 1 with water and reheating operation, and for setting the hot water supply temperature. A cleaning remote control 13 is communicatively connected to control unit 20 for starting a bathtub cleaning operation by bathtub cleaning device 10. Water heating device 2 and control unit 20 are communicatively connected to each other to obtain device status such as standby, bathtub cleaning operation, reheating operation, and combustion hot water supply from each other.

[0023] Next, the bathtub cleaning device 10 will be described. Supply unit 6 of bathtub cleaning device 10 has hot and cold water passage 14 that supplies hot and cold water from hot water supply passage 2a to cleaning nozzle 5, hot and cold water tank 15 (hot and cold water storage section) provided midway along hot and cold water passage 14 to store hot and cold water, and pump 16 for sending hot and cold water from hot and cold water tank 15 toward cleaning nozzle 5. A venturi 17 is interposed in hot and cold water passage 14 between pump 16 and cleaning nozzle 5 (downstream of pump 16). Venturi 17 corresponds to a detergent mixing section that mixes detergent into the hot and cold water sent out by pump 16 to be supplied to cleaning nozzle 5.

[0024] The hot water passage 14 is connected to the hot water supply passage 2a via a filter 14a, and has a parallel passage section 18 that branches and merges upstream of the hot water tank 15 and downstream of the filter 14a. In the parallel passage section 18, two branch passages 18a, 18b are connected in parallel.

[0025] The branch passage 18a is provided with a first solenoid valve 18c for opening and closing the branch passage 18a, and a constant flow valve 18e. The branch passage 18b is provided with a second solenoid valve 18d for opening and closing the branch passage 18b, and a constant flow valve 18f. The constant flow valves 18e and 18f are selected so that they each limit the flow rate to a value smaller than the discharge capacity of the pump 16, and the total flow rate of the two is greater than the normal flow rate of the pump 16. The flow rates in the branch passages 18a and 18b become equal when the first and second solenoid valves 18c and 18d are opened.

[0026] The hot and cold water passage 14 between the pump 16 and the venturi 17 is equipped with a temperature sensor 19, a flow rate sensor 14b, etc. A detergent passage 7a for supplying detergent from the detergent tank 7 is connected to the venturi 17, and detergent is supplied from the detergent passage 7a to the flowing hot and cold water by utilizing negative pressure generated by the flow of hot and cold water in the venturi 17. This detergent passage 7a is equipped with a detergent solenoid valve 7b (detergent valve) that opens and closes to switch between supplying and stopping detergent. Although not shown in the figure, the detergent solenoid valve 7b is a typical direct acting solenoid valve that, when not energized, closes the flow path by bringing a valve body formed of an elastic material into close contact with a valve seat provided in the flow path, and, when energized, opens the flow path by separating the valve body from the valve seat.

[0027] The control unit 20 is connected so as to be able to open and close the drain plug 4, the first and second solenoid valves 18c, 18d, the detergent solenoid valve 7b, and drive and stop the pump 16. The control unit 20 can also open and close the drain plug 4 in response to the operation of the drain switch 8. The control unit 20 is also connected to a float switch 15a that detects the water level in the hot and cold water tank 15, and a float switch 7c that detects the detergent liquid level in the detergent tank 7.

[0028] The hot and cold water tank 15 is set with a first water level L and a second water level H that is higher than the first water level L. The first water level L corresponds to a lower limit water level of the hot and cold water tank 15 that is preset for controlling the water level. The second water level H corresponds to an upper limit water level of the hot and cold water tank 15 that is preset for controlling the water level. Of the hot and cold water stored in the hot and cold water tank 15, any that exceeds the upper limit water level flows from overflow outlet 15b of the hot and cold water tank 15 into the bathtub pan and is drained from a bathroom drain not shown.

[0029] Control unit 20 is, for example, a computer equipped with an arithmetic unit, a storage device, an input / output device, etc., and controls the bathtub cleaning operation for cleaning bathtub 1 and the opening and closing of drain plug 4, etc., based on a control program stored in the storage device, etc. For example, when cleaning remote control 13 is operated to start the bathtub cleaning operation of bathtub cleaning device 10, control unit 20 executes the bathtub cleaning operation. Control unit 20 also detects the operation of drain switch 8 and drives drain plug 4 (open → close, or close → open), and the open / closed state of drain plug 4 is maintained until the next operation of drain switch 8 or a command from control unit 20 is received.

[0030] In the bathtub cleaning operation, the control unit 20 opens the drain plug 4 and controls the opening and closing of the first and second solenoid valves 18c, 18d and the detergent solenoid valve 7b, etc., and the driving of the pump 16. This bathtub cleaning operation will be described with reference to the flowchart in Figure 2. In the figure, Si (i = 1, 2,...) represents a step.

[0031] When the bathtub cleaning operation starts, in S1, the drain plug 4 is opened and the process proceeds to S2. Then, in S2, a preliminary cleaning is performed in which hot and cold water is sprayed from the cleaning nozzle 5 into the bathtub 1 for a predetermined preliminary cleaning time (e.g., 40 seconds). In the preliminary cleaning, while hot and cold water supplied from the water supply device 2 is stored in the hot and cold water tank 15, the pump 16 is driven so that the flow rate detected by the flow rate sensor 14b is a preset supply flow rate, and hot and cold water is sprayed from the cleaning nozzle 5 with the detergent solenoid valve 7b closed. At this time, solenoid valve control is performed for the first and second solenoid valves 18c, 18d so that the water level in the hot and cold water tank 15 is between the first water level L and the second water level H.

[0032] In solenoid valve control, for example, as shown in Fig. 3, in S11, both the first and second solenoid valves 18c, 18d are opened and the process proceeds to S12, where it is determined whether the water level in the hot and cold water tank 15 has reached the second water level H (upper limit water level). If the determination in S12 is No, the process returns to S12 with the first and second solenoid valves 18c, 18d open, and if the determination in S12 is Yes, the process proceeds to S13.

[0033] In S13, for example, the first solenoid valve 18c is left open while the second solenoid valve 18d is closed, and the process proceeds to S14, where it is determined whether the water level in the hot and cold water tank 15 has reached (dropped to) the first water level L (lower limit water level). If the determination in S14 is No, the process returns to S14 while maintaining the open / closed state of the first and second solenoid valves 18c, 18d, and if the determination in S14 is Yes, the process returns and starts the solenoid valve control from the beginning. When stopping the pump 16, the first and second solenoid valves 18c, 18d are closed.

[0034] This solenoid valve control is performed in the same way for the spraying of the cleaning liquid after the preliminary cleaning and for the rinsing cleaning. Note that in S13, the same solenoid valve may be closed each time, or a solenoid valve different from that used the previous time may be closed.

[0035] 2 is completed, the process proceeds to S3, where a cleaning liquid is sprayed to loosen dirt. In this spraying of the cleaning liquid, the detergent solenoid valve 7b is opened, and the cleaning liquid, which is obtained by mixing hot and cold water supplied to the cleaning nozzle 5 by driving the pump 16 with a detergent by the venturi 17, is sprayed from the cleaning nozzle 5 for a predetermined spraying time, and then the process waits for a predetermined waiting time. This spraying of the cleaning liquid and waiting is repeated a preset number of times (for example, seven times).

[0036] For example, as shown in Fig. 4, in the initial (first) injection of cleaning liquid, the set rotation speed of the stopped pump 16 is set to set rotation speed P1 which corresponds to the preset supply flow rate R1 at time t1, and a drive command is issued to the pump 16. Then, it is confirmed that the flow rate detected by the flow rate sensor 14b corresponds to the supply flow rate R1. Next, at time t2, the detergent solenoid valve 7b is opened to supply detergent to the venturi 17, and the cleaning liquid in which the detergent is mixed with hot and cold water is injected from the washing nozzle 5. Note that in the initial injection, the set rotation speed P1 is updated to the supply flow rate R1, and this updated set rotation speed P1 can be used as the rotation speed of the pump 16 for the next and subsequent injections.

[0037] At time t3, when a predetermined injection time has elapsed since time t2, the set rotation speed of pump 16 is set to zero and a stop command is issued to pump 16. Then, at time t4, when a preset delay time DT (for example, 1 second) has elapsed since time t3, detergent solenoid valve 7b is closed, and the system waits until a predetermined standby time has elapsed from time t3, when the stop command was issued to pump 16.

[0038] Even if a stop command is issued to the pump 16, the pump 16 does not stop instantly due to inertia, so the timing for closing the detergent solenoid valve 7b is delayed by a delay time DT after the stop command is issued to the pump 16. As a result, the supply flow rate of hot and cold water supplied to the washing nozzle 5 becomes lower than the supply flow rate R1 or becomes zero, so the negative pressure generated in the venturi 17 is weakened or eliminated. Therefore, the detergent solenoid valve 7b can be closed when the force pulling the valve body of the detergent solenoid valve 7b toward the venturi 17 side due to the negative pressure is weakened or does not act. The initial injection time may be longer than the injection time from the second onwards, taking into account that the hot and cold water from the venturi 17 to the washing nozzle 5 is pushed out by the washing liquid.

[0039] At time t5 when the standby time has elapsed, detergent solenoid valve 7b is opened for the second injection, and then at time t6 the set rotation speed of pump 16, which has been stopped, is set to set rotation speed P1 and a drive command is issued to pump 16 to inject cleaning liquid. The time between times t5 and t6 is short (for example, about 0.2 seconds) relative to the specified injection time. Since detergent solenoid valve 7b capable of supplying detergent is opened before pump 16 is driven, no negative pressure is generated in venturi 17 and detergent solenoid valve 7b can be opened without a force acting on the venturi 17 side to pull in the valve body of detergent solenoid valve 7b.

[0040] At time t7, when a predetermined injection time has elapsed since time t5, the set rotation speed of pump 16 is set to zero and a stop command is issued to pump 16, just like with the initial injection. Then, at time t8, when delay time DT has elapsed since time t7, detergent solenoid valve 7b is closed with the supply flow rate of hot and cold water supplied to washing nozzle 5 reduced or zero, and the system waits until a predetermined standby time has elapsed.

[0041] Bathtub cleaning device 10 repeats the same operation as the second spray until the spray one before the final spray. At this time, the supply flow rate of hot and cold water supplied to cleaning nozzle 5 is reduced or zero, so the negative pressure in venturi 17 is weakened or not generated. Therefore, detergent solenoid valve 7b is opened and closed when the force pulling the valve body of detergent solenoid valve 7b toward venturi 17 is weak or not acting, reducing the load on detergent solenoid valve 7b. Note that the spray time from the second spray onwards may be measured starting from the time when a drive command for pump 16 is issued.

[0042] In the final injection, the detergent solenoid valve 7b is kept closed, and the set rotation speed of the pump 16, which is stopped at time t9, is set to the set rotation speed P1 and an instruction to drive the pump 16 is issued. This causes the cleaning liquid remaining in the hot and cold water passage 14 between the venturi 17 and the cleaning nozzle 5 to be pushed out and injected by the hot and cold water, and the cleaning liquid is used up. Then, at time t 10 Then, the set rotation speed of the pump 16 is set to zero, and a stop command is issued to the pump 16. At time t 10 The cleaning liquid spray ends after a predetermined waiting time has elapsed. The spray time, waiting time, delay time, supply flow rate, etc. of the hot water and cleaning liquid can be set appropriately depending on the capacity, etc. of the bathtub cleaning device 10.

[0043] After the spraying of the cleaning liquid in S3 is completed, the process proceeds to S4, where a rinse is performed. In the rinse, like the preliminary wash in S2, hot and cold water is sprayed for a specified rinse time (e.g., 60 seconds) with detergent solenoid valve 7b closed to wash away dirt. After the rinse in S4 is completed, the process proceeds to S5, where first and second solenoid valves 18c and 18d are closed and pump 16 is driven until hot and cold water tank 15 is empty, after which the bathtub cleaning operation ends.

[0044] When the pump 16 is stopped during the injection of the cleaning liquid, for example, as shown in FIG. n After the set rotation speed P1 of the pump 16 is reduced to the predetermined stop preparation rotation speed P2, at time t n+1The set rotation speed of the pump 16 can be set to zero and a stop command can be issued to the pump 16. The stop preparation rotation speed P2 is set to a rotation speed at which a small supply flow rate R2 is generated in the venturi 17, which is weaker than the set rotation speed P1 or at which no negative pressure is generated. At time t n+1 At this time t n+1 The delay time DT has elapsed from the time t n+2 When the detergent solenoid valve 7b is closed, the supply flow rate is reduced more reliably than in the case of Figure 4 or is zero, and no pulling force toward the venturi 17 acts on the detergent solenoid valve 7b.

[0045] The operation and effects of the bathtub cleaning device 10 will now be described. In the bathtub cleaning device 10, the detergent solenoid valve 7b (detergent valve) is opened to mix the hot water supplied to the cleaning nozzle 5 by the drive of the pump 16 with the detergent in the venturi 17 (detergent mixing section) to generate cleaning liquid, and this cleaning liquid is sprayed from the cleaning nozzle 5. When spraying the cleaning liquid is stopped, the detergent solenoid valve 7b is kept open until a preset delay time DT has elapsed since a command to stop the pump 16 is issued, and the detergent solenoid valve 7b is closed after the delay time DT has elapsed. The rotation speed of the pump 16 decreases or the pump 16 stops before the delay time DT has elapsed, and the supply flow rate decreases or becomes zero, so that the negative pressure on the venturi 17 side of the detergent solenoid valve 7b is reduced or eliminated. Therefore, the detergent solenoid valve 7b is closed after the delay time DT has elapsed with the force pulling the detergent toward the venturi 17 weakened or not working, so that the load on the detergent solenoid valve 7b when spraying the cleaning liquid is stopped can be reduced.

[0046] In addition, when the spray of the cleaning liquid starts, the detergent solenoid valve 7b is opened without any pulling force acting on the venturi 17 side, so that it is possible to reduce the load on the detergent solenoid valve 7b when the spray of the cleaning liquid starts. Moreover, since the pump 16 is driven to mix the detergent from the time when the hot and cold water starts to flow, it is possible to prevent the previously sprayed cleaning liquid from being washed away by the hot and cold water.

[0047] Furthermore, it is also possible to issue a command to stop the pump 16 by lowering the set rotational speed of the pump 16 to the stop preparation rotational speed P2, thereby weakening the force pulling toward the venturi 17 or without this force being applied, and then close the detergent solenoid valve 7b after the set delay time DT has elapsed. Therefore, since the detergent solenoid valve 7b can be closed reliably without any pulling force being applied to the venturi 17, it is possible to reduce the load on the detergent solenoid valve 7b when spraying of the cleaning liquid is stopped.

[0048] The supply flow rate may be confirmed in a preliminary wash, and the detergent solenoid valve 7b may be opened from the first wash in the wash liquid injection, and then a drive command may be issued to the pump 16. Also, the detergent solenoid valve 7b may be opened in the final wash in the wash liquid injection to inject the generated wash liquid, and the remaining wash liquid may be used up in a rinse wash, and then the wash liquid may be rinsed away with hot and cold water. In addition, those skilled in the art may implement the above-mentioned embodiment in various modified forms without departing from the spirit of the present invention, and the present invention includes such modified forms. [Explanation of symbols]

[0049] 1: Bathtub 1a: Circulation adapter 2: Hot water supply equipment 2a: Hot water passage 3: Hot water filling and reheating passage 4: Drain plug 5: Cleaning nozzle 6: Supply unit 7: Detergent tank 7a: Detergent aisle 7b: Detergent solenoid valve (detergent valve) 7c: Detergent float switch 8: Drain switch 9: Power supply and communication unit 10: Bathtub cleaning device 11: Bathroom remote control 12: Kitchen remote control 13: Cleaning remote control 14:Hot water passage 14a: Filter 14b: Flow rate sensor (flow rate detection means) 15: Hot water tank (hot water storage section) 15a: Float switch 15b: Overflow port 16: Pump 17: Venturi (detergent mixing section) 18: Parallel passage section 18a, 18b: Branch passage 18c: First solenoid valve 18d: Second solenoid valve 18e, 18f: Constant flow valve 19: Temperature sensor 20: Control section

Claims

1. a control unit that drives the pump to drive the water passage and controls the spraying from the cleaning nozzle of cleaning liquid produced by mixing detergent in the detergent mixing unit with hot and cold water sent into the hot and cold water passage toward the cleaning nozzle; A bathtub cleaning device characterized in that, when stopping the spray of the cleaning liquid, the control unit closes the detergent valve after a predetermined delay time has elapsed since issuing a command to stop the pump.

2. The cleaning liquid is sprayed multiple times, The bathtub cleaning device described in claim 1, characterized in that, when starting at least the second or subsequent spraying of the cleaning liquid, the control unit opens the detergent valve while the pump is stopped, and issues a command to drive the pump while detergent can be supplied to the detergent mixing unit.

3. 3. The bathtub cleaning device according to claim 1, wherein the control unit issues the stop command after lowering the set rotational speed of the pump to a predetermined stop preparation rotational speed.

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