CN116458788A

CN116458788A - Micro-bubble generating device

Info

Publication number: CN116458788A
Application number: CN202310035553.XA
Authority: CN
Inventors: 中岛悠二郎
Original assignee: Rinnai Corp
Current assignee: Rinnai Corp
Priority date: 2022-01-19
Filing date: 2023-01-10
Publication date: 2023-07-21
Also published as: KR20230112534A; JP2023105545A

Abstract

The fine bubble generating device disclosed in the present specification comprises a tank, a tank supply path, a booster pump, a tank discharge path, a fine bubble generating nozzle, a tank circulation path, a tank circulation pump, a gas introduction mechanism, a liquid level electrode, and a control device. The gas introduction mechanism has a gas introduction port, a pressure reducing portion, and a gas introduction valve. The control device is capable of executing a fine bubble generation operation control in which the pressurizing pump is driven to supply the liquid under pressure to the tank and the liquid is supplied from the tank to the liquid tank. The control device drives the tank circulation pump to circulate the liquid in the tank during the execution of the micro-bubble generation operation control, thereby supplying the gas introduced from the gas introduction port to the tank, and controlling the opening and closing operation of the gas introduction valve based on information about whether or not the liquid level in the tank detected by the liquid level electrode is equal to or higher than a predetermined liquid level. Accordingly, the amount of information on the tank level can be reduced, and the rapidity of the judgment process on the opening and closing of the gas introduction valve can be ensured.

Description

Micro-bubble generating device

Technical Field

The present specification relates to a microbubble generating device.

Background

Patent document 1 discloses a microbubble generation device that includes: a tank for dissolving a gas in a liquid under pressure; a tank supply path that supplies the liquid to the tank; a pressurizing pump provided in the tank supply path; a tank discharge path for discharging the liquid in which the gas is dissolved under pressure from the tank to a liquid tank; a fine bubble generation nozzle provided in the tank discharge path, for depressurizing the liquid in which the gas is dissolved under pressure to generate fine bubbles; a tank circulation path provided separately from the tank discharge path and configured to convey the liquid from an outflow port connected to the tank to an inflow port connected to the tank; a tank circulation pump provided in the tank circulation path; a gas introduction mechanism provided in the tank circulation path; 2 liquid level electrodes capable of detecting whether the liquid level of the storage tank is above a prescribed liquid level; and a control device. The gas introduction mechanism includes: a pressure reducing unit that reduces pressure of the liquid; a gas introduction port for introducing the gas by a negative pressure of the liquid in the pressure reducing portion; and a gas introduction valve for opening and closing the gas introduction port. The control device is capable of executing a fine bubble generation operation control in which the pressurizing pump is driven to supply the liquid under pressure from the tank supply path to the tank, and the liquid in which the gas is dissolved under pressure is supplied from the tank to the liquid tank through the tank discharge path. The control device controls the opening and closing operation of the gas introduction valve based on information about whether or not the liquid level of the tank detected by one of the 2 liquid level electrodes is equal to or higher than a lower liquid level and information about whether or not the liquid level of the tank detected by the other of the 2 liquid level electrodes is equal to or higher than an upper liquid level by driving the tank circulation pump to circulate the liquid of the tank in the tank circulation path during execution of the microbubble generation operation control.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open publication No. 2015-127052

Disclosure of Invention

In the microbubble generation device, in order to ensure the rapidity of the judgment process concerning the opening and closing of the gas introduction valve, it is sometimes desirable to reduce the amount of information concerning the tank level. In the micro-bubble generating device of patent document 1, the control device is configured to control the opening and closing operation of the gas introduction valve based on information about whether the tank level is equal to or higher than the lower level and information about whether the tank level is equal to or higher than the upper level. In such a microbubble generation device, the amount of information on the tank level is relatively large, and the judgment processing on the opening and closing of the gas introduction valve may be less rapid. In the present specification, a technique is provided that can reduce the amount of information on the tank level, thereby ensuring the rapidity of the determination process regarding the opening and closing of the gas introduction valve. In the present specification, the 2 liquid level electrodes may be referred to as "lower liquid level electrode" and "upper liquid level electrode" for a micro-bubble generating device having 2 liquid level electrodes. Here, the "lower liquid level" is a liquid level lower than the "upper liquid level".

[ solution for solving the problems ]

The fine bubble generating apparatus disclosed in the present specification has a tank that pressurizes and dissolves gas in a liquid, a tank supply path, a pressurizing pump, a tank discharge path, a fine bubble generating nozzle, a tank circulation path, a tank circulation pump, a gas introduction mechanism, a liquid level electrode, and a control device; the tank supply path supplies the liquid to the tank; the pressurizing pump is provided in the tank supply path; the tank discharge path discharging the liquid in which the gas is dissolved under pressure from the tank to a liquid tank; the fine bubble generation nozzle is provided in the tank discharge path, and depressurizes the liquid in which the gas is dissolved under pressure to generate fine bubbles; the tank circulation path and the tank discharge path are provided separately, and the liquid is transported from an outflow port connected to the tank to an inflow port connected to the tank; the tank circulation pump is provided to the tank circulation path; the gas introduction mechanism is provided in the tank circulation path; the liquid level electrode is capable of detecting whether the liquid level of the storage tank is above a prescribed liquid level. The gas introduction mechanism has a pressure reducing portion that reduces the pressure of the liquid, a gas introduction port, and a gas introduction valve; the gas introduction port introduces the gas by a negative pressure of the liquid in the pressure reducing portion; the gas introduction valve opens and closes the gas introduction port. The control device is capable of executing a fine bubble generation operation control, which means: the pressurizing pump is driven to supply the liquid under pressure from the tank supply path to the tank and supply the liquid in which the gas is dissolved under pressure from the tank to the liquid tank through the tank discharge path. The control means performs the following processing (performs the following operation control) in the course of performing the fine bubble generation operation control: driving the tank circulation pump to circulate the liquid in the tank circulation path, thereby supplying the gas introduced through the gas introduction port to the tank; and controlling opening and closing operations of the gas introduction valve based on information about whether or not the liquid level of the tank detected by the liquid level electrode is equal to or higher than a predetermined liquid level.

Another microbubble generation device disclosed in the present specification has a tank that pressurizes and dissolves gas in a liquid, a tank supply path, a pressurizing pump, a tank discharge path, a microbubble generation nozzle, a tank circulation path, a tank circulation pump, a gas introduction mechanism, a single liquid level electrode, and a control device; the tank supply path supplies the liquid to the tank; the pressurizing pump is provided in the tank supply path; the tank discharge path discharging the liquid in which the gas is dissolved under pressure from the tank to a liquid tank; the fine bubble generation nozzle is provided in the tank discharge path, and depressurizes the liquid in which the gas is dissolved under pressure to generate fine bubbles; the tank circulation path and the tank discharge path are provided separately, and the liquid is transported from an outflow port connected to the tank to an inflow port connected to the tank; the tank circulation pump is provided to the tank circulation path; the gas introduction mechanism is provided in the tank circulation path; the single liquid level electrode is capable of detecting whether the liquid level of the storage tank is above a prescribed liquid level. The gas introduction mechanism has a pressure reducing portion that reduces the pressure of the liquid, a gas introduction port, and a gas introduction valve; the gas introduction port introduces the gas by a negative pressure of the liquid in the pressure reducing portion; the gas introduction valve opens and closes the gas introduction port. The control device is capable of executing a fine bubble generation operation control, which means: the pressurizing pump is driven to supply the liquid under pressure from the tank supply path to the tank, and the liquid in which the gas is dissolved under pressure is supplied from the tank to the liquid tank through the tank discharge path. The control means is capable of executing the following processing in executing the fine bubble generation operation control: and driving the tank circulation pump to circulate the liquid in the tank through the tank circulation path, thereby supplying the gas introduced through the gas introduction port to the tank, and controlling opening and closing operations of the gas introduction valve based on information about whether or not the liquid level of the tank detected by the single liquid level electrode is equal to or higher than a predetermined liquid level.

According to the above configuration, the control device is configured to control the opening and closing operation of the gas introduction valve based on information about whether or not the tank level detected by the 1-level electrodes is equal to or higher than a predetermined level. Therefore, the amount of information on the tank level can be reduced, and thus the rapidity of the judgment process on the opening and closing of the gas introduction valve can be ensured.

In 1 or more embodiments, the control device may perform the following processing in the process of performing the microbubble generation operation control: when the liquid level of the storage tank is detected to be lower than the predetermined liquid level by the liquid level electrode in a state where the gas introduction valve is opened, the gas introduction valve is closed, the gas introduction valve is kept in a closed state until a 1 st predetermined time elapses after the gas introduction valve is closed, and the gas introduction valve is opened after the 1 st predetermined time elapses.

In the micro-bubble generating device, droplets scattered from the liquid surface of the tank adhere to the liquid level electrode, and thus the liquid level electrode may generate mucus. When the liquid level electrode generates mucus, there is concern that the liquid level of the storage tank is erroneously detected. For example, the micro-bubble generating device has a lower liquid level electrode and an upper liquid level electrode, and when the control device performs control of the opening and closing operation of the gas introduction valve so that the liquid level of the tank changes between the lower liquid level and the upper liquid level, the upper liquid level electrode is hardly immersed in the liquid. Therefore, the upper liquid level electrode cannot suppress the generation of mucus, and may erroneously detect the liquid level of the tank. According to the above configuration, in the process of executing the fine bubble generation operation control, by frequently immersing the liquid level electrode in the liquid, the generation of the mucus by the liquid level electrode can be suppressed. Therefore, false detection of the liquid level of the tank can be suppressed.

In 1 or more embodiments, the control device may perform the following processing in the process of performing the microbubble generation operation control: and determining an elapsed time from when the gas introduction valve is opened in the closed state to when the gas introduction valve is closed by the liquid level electrode detecting that the liquid level of the tank is lower than the predetermined liquid level, wherein the elapsed time is set to be an intake time, and when the intake time exceeds an upper limit intake time, the rotation speed of the pressurizing pump is reduced when the pressurizing pump is driven thereafter.

If the suction time is too long, the amount of liquid supplied to the tank is assumed to be too large or the amount of gas introduced by the gas introduction mechanism is assumed to be too small. The amount of liquid supplied to the tank increases as the rotation speed of the pressure pump increases, and the amount of liquid supplied to the tank decreases as the rotation speed of the pressure pump decreases. According to the above configuration, when the suction time exceeds the upper limit suction time, that is, when the suction time is too long, the amount of liquid supplied to the tank can be reduced by decreasing the rotation speed of the pressurizing pump, thereby achieving a reduction in the suction time.

In 1 or more embodiments, the control device may perform the following processing in the process of performing the microbubble generation operation control: and determining an elapsed time from when the gas introduction valve is opened in the closed state to when the gas introduction valve is closed by detecting that the liquid level of the tank is lower than the predetermined liquid level by the liquid level electrode, and increasing the rotation speed of the pressurizing pump when the pressurizing pump is driven thereafter when the suction time is lower than a lower limit suction time.

It is assumed that the amount of liquid supplied to the tank is too small or the amount of gas introduced by the gas introduction mechanism is too large when the suction time is too short. According to the above configuration, when the suction time is less than the lower limit suction time, that is, when the suction time is too short, the amount of liquid supplied to the tank can be increased by increasing the rotation speed of the pressurizing pump, so that the suction time can be prolonged.

In 1 or more embodiments, the control device may perform the following processing in the process of performing the microbubble generation operation control: and determining an elapsed time from when the gas introduction valve is opened in the closed state to when the gas introduction valve is closed by detecting that the liquid level of the tank is lower than the predetermined liquid level by the liquid level electrode, and increasing the rotational speed of the tank circulation pump when the tank circulation pump is driven in the state where the gas introduction valve is opened after the elapsed time exceeds an upper limit suction time.

If the suction time is too long, the amount of liquid supplied to the tank is assumed to be too large or the amount of gas introduced by the gas introduction mechanism is assumed to be too small. In addition, in a state where the gas introduction valve is opened, the higher the rotational speed of the tank circulation pump, the more the amount of gas introduced by the gas introduction mechanism increases, and the lower the rotational speed of the tank circulation pump, the more the amount of gas introduced by the gas introduction mechanism decreases. According to the above configuration, when the intake time exceeds the upper limit intake time, that is, when the intake time is too long, the amount of gas introduced by the gas introduction mechanism can be increased by increasing the rotation speed of the tank circulation pump, thereby achieving a reduction in the intake time.

In 1 or more embodiments, the control device may perform the following processing in the process of performing the microbubble generation operation control: and determining an elapsed time from when the gas introduction valve is opened in the closed state to when the gas introduction valve is closed by detecting that the liquid level of the tank is lower than the predetermined liquid level by the liquid level electrode, and when the suction time is lower than a lower limit suction time, reducing the rotational speed of the tank circulation pump when the tank circulation pump is driven in the state where the gas introduction valve is opened thereafter.

It is assumed that the amount of liquid supplied to the tank is too small or the amount of gas introduced by the gas introduction mechanism is too large when the suction time is too short. According to the above configuration, when the intake time is less than the lower limit intake time, that is, when the intake time is too short, the amount of gas introduced by the gas introduction mechanism can be reduced by reducing the rotation speed of the tank circulation pump, thereby realizing an extension of the intake time.

In 1 or more embodiments, the control device may perform the following processing in the process of performing the microbubble generation operation control: it is possible to determine whether or not a stop condition for stopping the microbubble generation operation control is satisfied, execute a stop process for stopping the microbubble generation operation control if the stop condition is satisfied, and execute the following process when executing the stop process: the gas introduction valve is opened in a state where the pressurizing pump and the tank circulation pump are driven, and when the liquid level of the tank is detected to be lower than the predetermined liquid level by the liquid level electrode in a state where the gas introduction valve is opened, the gas introduction valve is closed, the gas introduction valve is kept closed until a 2 nd predetermined time, which is a time longer than the 1 st predetermined time, has elapsed since the gas introduction valve was closed, and after the 2 nd predetermined time has elapsed, the pressurizing pump and the tank circulation pump are stopped to stop the microbubble generation operation control.

According to the above configuration, the fine bubble generation operation control can be stopped in a state where the liquid level electrode is immersed in the liquid. Accordingly, the generation of mucus on the liquid level electrode can be suppressed, and thus false detection of the liquid level of the tank can be suppressed. In addition, according to the above configuration, when the fine bubble generation operation control is stopped, the portion of the liquid level electrode above the portion immersed in the liquid during the normal operation control is also immersed in the liquid. Therefore, the generation of mucus at the liquid level electrode can be suppressed more suitably.

In 1 or more embodiments, the control device may perform the following processing in the process of performing the microbubble generation operation control: when the liquid level of the storage tank is detected to be equal to or higher than the predetermined liquid level by the liquid level electrode in a state where the gas introduction valve is closed, the gas introduction valve is opened, the gas introduction valve is maintained in an opened state until a 3 rd predetermined time has elapsed since the gas introduction valve was opened, and the gas introduction valve is closed after the 3 rd predetermined time has elapsed.

For example, the microbubble generation device has a lower liquid level electrode and an upper liquid level electrode, and when the control device performs control of the opening and closing operation of the gas introduction valve so that the liquid level of the tank changes between the lower liquid level and the upper liquid level, the length of the lower liquid level electrode needs to be relatively long. In this case, the weight of the entire apparatus may be increased. According to the above configuration, the length of the liquid level electrode can be made relatively short. Therefore, the weight of the entire device can be reduced.

In 1 or more embodiments, the liquid may be water. The liquid tank may be a bath tub for a user to bath.

According to the above configuration, in the micro-bubble generating device for generating micro-bubbles in the water of the bathtub for bathing by the user, the amount of information on the water level of the tank can be reduced, and thus the rapidity of the judgment process regarding the opening and closing of the gas introduction valve can be ensured.

Drawings

Fig. 1 is a diagram schematically showing the structure of a water heating apparatus 2 according to examples 1 to 3.

Fig. 2 is a diagram schematically showing an example of the flow of water in the bathtub adapter 132 of the water heater 2 according to embodiments 1 to 3.

Fig. 3 is a view schematically showing another example of the flow of water in the bathtub adapter 132 of the water heating apparatus 2 of embodiments 1 to 3.

Fig. 4 is a diagram schematically showing an example of the flow of water in the water heater 2 according to examples 1 to 3.

Fig. 5 is a diagram schematically showing another example of the flow of water in the water heating device 2 of examples 1 to 3.

Fig. 6 is a diagram schematically showing another example of the flow of water in the water heating device 2 of embodiments 1 to 3.

Fig. 7 is a flowchart of the process performed by the control device 150 in the micro-bubble generation operation control of the water heating device 2 of embodiment 1.

Fig. 8 is a flowchart of a stopping process performed by the control device 150 in the process shown in fig. 7, the process shown in fig. 9, or the process shown in fig. 10 in the microbubble generation operation control of the water heating device 2 of embodiments 1 to 3.

Fig. 9 is a flowchart of the processing performed by the control device 150 in the fine bubble generation operation control of the water heating device 2 of embodiment 2.

Fig. 10 is a flowchart of the process performed by the control device 150 in the micro-bubble generation operation control of the water heating device 2 of embodiment 3.

Description of the reference numerals

2: a water heating device; 10: a heat source unit; 12: a 1 st heat source unit; 14: a 2 nd heat source unit; 16: a water supply path; 18: a hot water path; 18a: a hot water temperature thermistor; 20: a bypass path; 22: a bypass servo; 24: a hot water injection path; 26: a valve; 28: a water quantity sensor; 30: circularly going out; 30a: a circulating outgoing thermistor; 32: a circulation loop; 32a: a circulation loop thermistor; 34: a bathtub circulation pump; 36: a water flow switch; 50: an air pressurizing and dissolving unit; 52: a storage tank; 54: a water level electrode; 60: a heat source circuit; 62: 1 st bathtub waterway; 64: the storage tank is taken off; 66: a communication path; 68: the heat source goes to the way; 70: 2 nd bathtub waterway; 74: a tank circuit; 74a: a water feed mouth; 80: a 1 st three-way valve; 82: a 2 nd three-way valve; 84: a one-way valve; 86: a storage tank water supply valve; 88: a 1 st pressurizing pump; 90: a 2 nd pressurizing pump; 92: a tank circulation path; 92a: an outflow port; 94: a tank circulation pump; 96: a gas introduction mechanism; 98: a water inlet pipe; 100: a water outlet pipe; 102: a venturi; 104: a gas introduction path; 104a: a gas inlet; 106: a gas introduction valve; 130: a bathtub; 130a: a wall portion; 132: a bathtub adapter; 132a: a front surface; 132b: a lower surface; 134a: a 1 st discharge port; 134b: a 1 st suction inlet; 134c: a 2 nd suction inlet; 134d: a 2 nd discharge port; 136: a 1 st waterway; 136a: a 1 st discharge path; 136b: a 1 st suction path; 138: a 2 nd waterway; 138a: a 2 nd discharge path; 138b: a 2 nd suction path; 140a, 140b, 140c, 140d: a non-return part; 142: a fine bubble generation nozzle; 150: a control device; 152: a memory; 154: a remote controller; 200: a water supply source; 250: a water tap.

Detailed Description

Example 1

As shown in fig. 1, the water heating apparatus 2 of the present embodiment has a heat source unit 10, an air-pressurized dissolving unit 50, a bathtub adapter 132, and a control apparatus 150. The water heater 2 can heat water supplied from a water supply source 200 such as tap water and supply water heated to a desired temperature to a faucet 250 provided in a kitchen or the like and a bathtub 130 provided in a bathroom. The water heater 2 can generate fine bubbles in water in the bath tub 130 for a user to bath.

(Structure of Heat Source Unit 10)

The heat source unit 10 includes a 1 st heat source unit 12, a 2 nd heat source unit 14, a water supply path 16, a hot water path 18, a bypass path 20, a bypass servo 22, a hot water injection path 24, a hot water injection valve 26, a water amount sensor 28, a circulation outgoing path 30, a circulation circuit 32, a bathtub circulation pump 34, and a water flow switch 36.

The upstream end of the water supply path 16 is connected to the water supply source 200, and the downstream end of the water supply path 16 is connected to the 1 st heat source unit 12. The upstream end of the hot water path 18 is connected to the 1 st heat source unit 12, and the downstream end of the hot water path 18 is connected to the faucet 250. The 1 st heat source unit 12 is a combustion heat source unit that heats water by combustion of gas, for example. The 1 st heat source unit 12 heats water flowing in from the water supply path 16, and sends the heated water to the hot water path 18.

The upstream end of the bypass path 20 is connected to the water supply path 16, and the downstream end of the bypass path 20 is connected to the hot water path 18. The bypass servo 22 is provided at a portion where the bypass path 20 is connected to the water supply path 16. The bypass servo 22 can adjust the ratio of the flow rate of water flowing from the water supply path 16 to the hot water path 18 via the 1 st heat source unit 12 and the flow rate of water flowing from the water supply path 16 to the hot water path 18 via the bypass path 20 by adjusting the opening degree of the built-in valve body. By adjusting the opening degree of the bypass servo 22, the hot water path 18 downstream of the portion where the bypass path 20 is connected is supplied with water in which the high-temperature water flowing from the 1 st heat source unit 12 and the low-temperature water flowing from the bypass path 20 are mixed in a desired ratio and adjusted to a desired temperature. A hot water temperature thermistor 18a is provided in the hot water path 18 downstream of the portion where the bypass path 20 is connected, and the hot water temperature thermistor 18a detects the temperature of water in the hot water path 18.

The upstream end of the hot water injection path 24 is connected to the hot water path 18 downstream of the portion to which the bypass path 20 is connected, and the downstream end of the hot water injection path 24 is connected to the circulation circuit 32. The hot water injection valve 26 is provided in the hot water injection path 24, and opens and closes the hot water injection path 24. The hot water injection valve 26 is normally closed. The water amount sensor 28 is provided in the hot water injection path 24, and detects the amount of water flowing through the hot water injection path 24.

The upstream end of the circulation circuit 32 is connected to a heat source circuit 60 (described later) of the air pressure dissolving unit 50, and the downstream end of the circulation circuit 32 is connected to the 2 nd heat source unit 14. The upstream end of the circulation path 30 is connected to the 2 nd heat source unit 14, and the downstream end of the circulation path 30 is connected to a heat source path 68 (described later) of the air pressure dissolving unit 50. The 2 nd heat source unit 14 is a combustion heat source unit that heats water by combustion of gas, for example. The 2 nd heat source unit 14 heats the water flowing in from the circulation circuit 32 and sends the heated water to the circulation outlet 30. A circulation circuit thermistor 32a that detects the temperature of water in the circulation circuit 32 is provided near the upstream end of the circulation circuit 32. A circulation outgoing thermistor 30a for detecting the temperature of water in the circulation outgoing path 30 is provided near the downstream end of the circulation outgoing path 30.

The bathtub circulation pump 34 is provided in the circulation circuit 32 downstream of the connection point of the hot water injection path 24, and sends water in the circulation circuit 32 to the 2 nd heat source unit 14. The water flow switch 36 is provided in the circulation circuit 32 between the bathtub circulation pump 34 and the 2 nd heat source unit 14, and detects whether or not water flows through the circulation circuit 32.

(Structure of air pressure dissolving unit 50)

The air pressure dissolving unit 50 has a tank 52, a heat source circuit 60, a heat source outlet 68, a tank circuit 74, a tank outlet 64, a communication path 66, a 1 st three-way valve 80, a 2 nd three-way valve 82, a one-way valve 84, a tank water feed valve 86, a 1 st pressurizing pump 88, a 2 nd pressurizing pump 90, a tank circulation path 92, a tank circulation pump 94, and a gas introduction mechanism 96.

The tank 52 is used to dissolve air in water under pressure to produce air-dissolved water. The reservoir 52 is capable of storing water therein. A water level electrode 54 and a ground electrode (not shown) for detecting the water level in the tank 52 are provided in the tank 52. When the water level electrode 54 contacts the surface of the water stored in the tank 52, a current flows between the water level electrode 54 and the ground electrode, and an ON signal is output to the control device 150. That is, the water level electrode 54 is configured to be able to detect whether or not the water level in the tank 52 is equal to or higher than a predetermined water level. Hereinafter, the water level in the tank 52 detected by the water level electrode 54 is sometimes referred to as "boundary water level".

One end of the heat source circuit 60 is connected to the communication path 66, and the other end of the heat source circuit 60 is connected to the circulation circuit 32 of the heat source unit 10. The communication passage 66 connects the 1 st three-way valve 80 and the 2 nd three-way valve 82. The 1 st three-way valve 80 is connected to the communication passage 66, the 1 st bathtub water passage 62, and the tank outlet passage 64. The 1 st three-way valve 80 is capable of switching between a 1 st communication state (see fig. 6), a 2 nd communication state (see fig. 1), and a 3 rd communication state (see fig. 4 and 5), wherein the 1 st communication state is a state in which the tank outlet 64 and the 1 st bathtub water channel 62 are in communication; the 2 nd communication state is a state in which the tank outgoing path 64 and the communication path 66 are communicated; the 3 rd communication state is a state in which the 1 st bathtub waterway 62, the tank outgoing passage 64, and the communication passage 66 are communicated. The upstream end of the tank outgoing path 64 is connected to the lower portion of the tank 52, and the downstream end of the tank outgoing path 64 is connected to the 1 st three-way valve 80. A one-way valve 84 is provided in the tank outlet 64, the one-way valve 84 allowing water to flow from the tank 52 to the 1 st three-way valve 80 and prohibiting water flow from the 1 st three-way valve 80 to the tank 52. One end of the 1 st bathtub water circuit 62 is connected to the 1 st three-way valve 80 and the other end of the 1 st bathtub water circuit 62 is connected to the bathtub adapter 132.

One end of the heat source outward path 68 is connected to the circulation outward path 30 of the heat source unit 10, and the other end of the heat source outward path 68 is connected to the 2 nd three-way valve 82. The communication passage 66, the heat source outlet passage 68, and the 2 nd bathtub water passage 70 are connected to the 2 nd three-way valve 82. The 2 nd three-way valve 82 is capable of switching between a 4 th communication state (see fig. 6) in which the 2 nd bathtub water passage 70 and the communication passage 66 communicate with each other, and a 5 th communication state (see fig. 1, 4, and 5); the 5 th communication state is a state in which the heat source outlet 68 and the 2 nd bathtub water channel 70 are in communication. One end of the 2 nd bathtub water circuit 70 is connected to the 2 nd three-way valve 82 and the other end of the 2 nd bathtub water circuit 70 is connected to the bathtub adapter 132.

The upstream end of the tank circuit 74 is connected to the heat source outlet 68, and the downstream end of the tank circuit 74 is connected to the tank 52 through the water feed port 74 a. The tank water feed valve 86 is provided in the tank circuit 74 and opens and closes the tank circuit 74. The tank water feed valve 86 is normally closed. The 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 are provided in the tank circuit 74 between the tank water feed valve 86 and the tank 52. The 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 pressurize the water in the tank circuit 74 and send it out to the tank 52. In the tank circuit 74, the 1 st pressurizing pump 88 is disposed upstream of the 2 nd pressurizing pump 90.

An upstream end (hereinafter also referred to as an outflow port 92 a) of the tank circulation path 92 is connected to the bottom of the tank 52, and a downstream end of the tank circulation path 92 is connected to the tank circuit 74 downstream of the 2 nd booster pump 90. The water level at the portion where the outflow port 92a of the tank circulation path 92 is connected to the tank 52 is lower than the boundary water level. The tank circulation pump 94 is provided in the tank circulation path 92. The tank circulation pump 94 sucks water in the tank 52 into the tank circulation path 92 through the outflow port 92a, and discharges water in the tank circulation path 92 into the tank 52 through the water feed port 74a at the downstream end of the tank circuit 74.

The gas introduction mechanism 96 is provided in the tank circulation path 92 upstream of the tank circulation pump 94. The gas introduction mechanism 96 has a water inlet pipe 98, a water outlet pipe 100, a venturi 102, a gas introduction path 104, and a gas introduction valve 106. Water flows into the water pipe 98 from the upstream side of the tank circulation path 92. The water outlet pipe 100 flows out water to the downstream side of the tank circulation path 92. Venturi 102 communicates with inlet tube 98 and outlet tube 100. Venturi 102 has a smaller diameter than the inlet 98 and outlet 100 tubes. The water flowing through the gas introduction mechanism 96 is depressurized to a pressure lower than the atmospheric pressure when flowing from the water inlet pipe 98 to the venturi 102, and is pressurized to the original pressure when flowing from the venturi 102 to the water outlet pipe 100. An upstream end (hereinafter, also referred to as a gas inlet 104 a) of the gas introduction path 104 is open to the atmosphere, and a downstream end is connected to the venturi 102. The gas introduction valve 106 is provided in the gas introduction path 104, and opens and closes the gas introduction path 104. When water flows through the gas introduction mechanism 96, air is sucked into the gas introduction path 104 from the gas introduction port 104a with the gas introduction valve 106 in an open state, and the air is mixed with water flowing through the venturi 102. The air introduced from the gas introduction path 104 flows into the tank 52 together with the water flowing through the tank circulation path 92. The gas introduction valve 106 is normally closed.

(Structure of bathtub adapter 132)

Next, a bathtub adapter 132 provided in a wall 130a of the bathtub 130 will be described with reference to fig. 2 and 3. Fig. 2 shows the flow of water in the bathtub adapter 132 in a state where water flows from the 1 st bathtub water circuit 62 to the bathtub 130, and water flows from the bathtub 130 to the 2 nd bathtub water circuit 70 (e.g., the state of fig. 6). Fig. 3 shows the flow of water in the bathtub adapter 132 in a state where water flows from the bathtub 130 to the 1 st bathtub water circuit 62, and water flows from the 2 nd bathtub water circuit 70 to the bathtub 130 (e.g., the state of fig. 5).

Bathtub adapter 132 has a 1 st waterway 136 and a 2 nd waterway 138. The 1 st waterway 136 communicates with the 1 st bathtub waterway 62, and the 2 nd waterway 138 communicates with the 2 nd bathtub waterway 70. The 1 st waterway 136 branches into a 1 st discharge path 136a and a 1 st suction path 136b. The 1 st discharge path 136a communicates with the 1 st discharge port 134a provided in the front surface 132a of the bathtub adapter 132. The water discharged from the 1 st drain 134a to the bathtub 130 is discharged in front of the wall 130a of the bathtub 130, i.e., in a direction perpendicular to the wall 130a of the bathtub 130. The 1 st discharge path 136a is provided with: a non-return portion 140a that prevents water from flowing from the bathtub 130 to the 1 st bathtub water channel 62; and a fine bubble generating nozzle 142 disposed upstream of the non-return portion 140a (on the 1 st bathtub water channel 62 side). The fine bubble generation nozzle 142 decompresses water passing through the fine bubble generation nozzle 142. The 1 st suction path 136b communicates with the 1 st suction port 134b provided in the front surface 132a of the bathtub adapter 132. The 1 st suction path 136b is provided with a non-return portion 140b, and the non-return portion 140b prevents water from flowing from the 1 st bathtub water path 62 to the bathtub 130.

The 2 nd waterway 138 branches into a 2 nd discharge path 138a and a 2 nd suction path 138b. The 2 nd suction path 138b communicates with a 2 nd suction port 134c provided in the front surface 132a of the bathtub adapter 132. The 2 nd suction path 138b is provided with a non-return portion 140c, and the non-return portion 140c prevents water from flowing from the 2 nd bathtub water path 70 to the bathtub 130. The 2 nd discharge path 138a communicates with a 2 nd discharge port 134d provided in the lower surface 132b of the bathtub adapter 132. The water discharged from the 2 nd discharge port 134d is discharged downward, that is, in a direction parallel to the wall 130a of the bathtub 130. The 2 nd discharge path 138a is provided with a non-return portion 140d, and the non-return portion 140d prevents water from flowing from the bathtub 130 to the 2 nd bathtub water path 70.

(Structure of control device 150)

The control device 150 shown in fig. 1 controls the operations of the respective constituent elements of the heat source unit 10 and the air pressure dissolving unit 50. The control device 150 is configured to be capable of communicating with a remote control 154 operable by a user. The control device 150 has a memory 152, and can store various settings such as a set temperature or a set water amount in the hot water injection operation control, and a set temperature in the reheating operation control, which are input by a user. The user can instruct the start or end of hot water injection operation control, reheating operation control, and microbubble generation operation control, which will be described later, through the remote controller 154.

(control of hot Water injection operation)

The hot water injection operation control is started in a case where the user instructs the start of the hot water injection operation control through the remote controller 154. Alternatively, the hot water injection operation control may be started when the user sets the start time of the hot water injection operation control in advance by the remote controller 154 and the control device 150 determines that the start time of the hot water injection operation control has come. When the hot water injection operation control is started, the control device 150 sets the 1 st three-way valve 80 and the 2 nd three-way valve 82 to the 3 rd communication state and the 5 th communication state, respectively (see fig. 4 and 5). When the hot water injection operation control is started, the control device 150 opens the hot water injection valve 26 and starts heating by the 1 st heat source machine 12. Accordingly, as shown in fig. 4, the water adjusted to the set temperature flows from the hot water path 18 into the circulation circuit 32 via the hot water injection path 24. The water flowing into the circulation circuit 32 is split into an upstream side (i.e., the heat source circuit 60) and a downstream side (i.e., the 2 nd heat source machine 14). Water flowing from circulation loop 32 to heat source loop 60 flows into bathtub 130 via communication channel 66, three-way valve 1, bathtub water circuit 1, 62, and bathtub adapter 132. The water flowing from the circulation circuit 32 to the 2 nd heat source unit 14 flows into the bathtub 130 via the circulation outlet 30, the heat source outlet 68, the 2 nd three-way valve 82, the 2 nd bathtub water channel 70, and the bathtub adapter 132. The control device 150 stands by until the accumulated water amount detected by the water amount sensor 28 reaches the set water amount in the hot water injection operation control. The accumulated water amount is the accumulated water amount detected by the water amount sensor 28 from the start of the hot water injection operation control. When the accumulated water amount reaches the set water amount, the control device 150 closes the hot water injection valve 26, and the heating of the water by the 1 st heat source unit 12 is completed. After that, the control device 150 informs the user of the completion of the hot water injection operation control through the remote controller 154, ending the hot water injection operation control.

(reheat operation control)

The reheating operation control is started in a case where the user instructs to start the reheating operation control through the remote controller 154. Alternatively, the reheating operation control may be started when the control device 150 determines that the temperature detected by the circulation circuit thermistor 32a does not satisfy the set temperature after the heating of the water by the 1 st heat source unit 12 ends in the hot water injection operation control. When the reheating operation control is started, the control device 150 sets the 1 st three-way valve 80 to the 3 rd communication state and sets the 2 nd three-way valve 82 to the 5 th communication state (see fig. 4 and 5). Based on this state, the control device 150 drives the bathtub circulation pump 34, and starts heating the water by the 2 nd heat source unit 14. Accordingly, as shown in fig. 5, the water in the bathtub 130 is sent to the 2 nd heat source unit 14 via the bathtub adapter 132, the 1 st bathtub water channel 62, the 1 st three-way valve 80, the communication channel 66, the heat source circuit 60, and the circulation circuit 32. The water heated by the heat source unit 2 14 returns to the bathtub 130 via the circulation outlet 30, the heat source outlet 68, the three-way valve 2, the bathtub water channel 2 70, and the bathtub adapter 132. When the temperature detected by the circulation circuit thermistor 32a reaches the set temperature or higher, the control device 150 stops the bathtub circulation pump 34 and ends the heating of the water by the 2 nd heat source unit 14. After that, the control device 150 notifies the user of the completion of the reheating operation control through the remote controller 154, ending the reheating operation control.

(micro-bubble generation operation control)

The microbubble generation operation control is started when the user instructs to start the microbubble generation operation control via the remote controller 154. In the water heating device 2 of the present embodiment, the operation control for generating fine bubbles is automatically started after the completion of the operation control for injecting hot water. That is, the fine bubble generation operation control is executed in association with the execution of the hot water injection operation control. When the microbubble generation operation control is started, the control device 150 sets the 1 st three-way valve 80 and the 2 nd three-way valve 82 to the 3 rd communication state and the 5 th communication state, respectively (see fig. 4 and 5). Further, the control device 150 sets the tank water feed valve 86 to an open state. Based on this state, the control device 150 executes the processing shown in fig. 7.

In S2, the control device 150 drives the tank circulation pump 94. Accordingly, water circulates between the tank 52 and the tank circulation path 92.

In S4, the control device 150 opens the gas introduction valve 106. Accordingly, air is introduced into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92.

In S6, control device 150 starts supplying air-dissolved water from tank 52 to bathtub 130. Specifically, as shown in fig. 6, the control device 150 sets the 1 st three-way valve 80 to the 1 st communication state, sets the 2 nd three-way valve 82 to the 4 th communication state, and drives the bathtub circulation pump 34, the 1 st pressurizing pump 88, and the 2 nd pressurizing pump 90. Accordingly, the water in the bathtub 130 is supplied to the tank 52 via the bathtub adapter 132, the 2 nd bathtub water passage 70, the 2 nd three-way valve 82, the communication passage 66, the heat source circuit 60, the circulation circuit 32, the 2 nd heat source unit 14, the circulation outgoing passage 30, the heat source outgoing passage 68, and the tank circuit 74. At this time, water pressurized by the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 is supplied from the tank circuit 74 to the tank 52. Accordingly, inside the tank 52, dissolved air is pressurized in the water. The pressurized air-dissolved water is then supplied from the tank 52 to the bathtub 130 via the tank outlet 64, the 1 st three-way valve 80, the 1 st bathtub water circuit 62, and the bathtub adapter 132. At this time, the water in which the air is dissolved under pressure is depressurized to an atmospheric pressure or lower when passing through the fine air bubble generating nozzle 142 of the 1 st discharge path 136a of the bathtub adapter 132, and is pressurized to an atmospheric pressure when being discharged to the bathtub 130, so that fine air bubbles are generated in the water of the bathtub 130.

In S8, the control device 150 determines whether or not the water level of the tank 52 is lower than the boundary water level based ON the presence or absence of the ON signal output from the water level electrode 54. In the present embodiment, in the gas introduction mechanism 96, the amount of air introduced when the gas introduction valve 106 is in the open state is larger than the amount of air of the fine bubbles generated in the water in the bathtub 130. Therefore, in a state where the gas introduction valve 106 is opened, the amount of air in the tank 52 increases, and the water level in the tank 52 decreases. When the water level of the tank 52 is equal to or higher than the boundary water level (no), the process repeats S8. If the water level of the tank 52 is lower than the boundary water level (yes), the process proceeds to S10.

In S10, the control device 150 closes the gas introduction valve 106. Accordingly, the air introduction into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92 is stopped. Since air is not supplied to the tank 52 in a state where the gas introduction valve 106 is closed, the amount of air in the tank 52 decreases and the water level in the tank 52 increases. In the present embodiment, the tank circulation pump 94 is also driven continuously while the gas introduction valve 106 is closed. Accordingly, the flow of water within the reservoir 52 is promoted, thereby promoting pressurized dissolution of air into the water in the reservoir 52.

In S12, the control device 150 starts counting the water level rising time by using a built-in timer (not shown).

In S14, the control device 150 determines whether or not the water level rise time counted at S12 exceeds the 1 st predetermined time (for example, 90 seconds). When the water level rising time is equal to or less than the 1 st predetermined time (no), the process repeats S14. If the water level rise time exceeds the 1 st predetermined time (yes), the process proceeds to S16.

In S16, the control device 150 ends the timing of the water level rising time by a built-in timer (not shown).

In S18, the control device 150 opens the gas introduction valve 106. Accordingly, the air is restarted to be introduced into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92.

In S20, the control device 150 starts the timing of the intake time using a built-in timer (not shown).

In S22, the control device 150 determines whether or not the water level of the tank 52 is lower than the boundary water level based ON the presence or absence of the ON signal output from the water level electrode 54. When the water level of the tank 52 is equal to or higher than the boundary water level (no), the process repeats S22. If the water level of the tank 52 is lower than the boundary water level (yes), the process proceeds to S24.

In S24, the control device 150 closes the gas introduction valve 106. Accordingly, the air introduction into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92 is stopped.

In S26, control device 150 ends the counting of the intake time by a built-in timer (not shown). The control device 150 stores the intake time at the end of the timing in the memory 152.

In S28, control device 150 determines whether or not the intake time stored in memory 152 in S26 exceeds a predetermined upper limit intake time (for example, 120 seconds). If the intake time exceeds the upper limit intake time (yes), the process proceeds to S30. When the intake time is equal to or less than the upper limit intake time (no), the process proceeds to S32.

In S30, control device 150 decreases the rotation speeds of 1 st pressurizing pump 88 and 2 nd pressurizing pump 90 by a predetermined value (for example, 10 Hz). Accordingly, in the case where the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 are driven thereafter, the amount of water supplied to the tank 52 decreases. After S30, the process advances to S32.

In S32, the control device 150 determines whether or not the intake time stored in the memory 152 in S26 is lower than a predetermined lower limit intake time (for example, 60 seconds). If the intake time is lower than the lower limit intake time (yes), the process proceeds to S34. When the intake time is equal to or longer than the lower limit intake time (no), the process proceeds to S36.

In S34, control device 150 increases the rotational speeds of 1 st pressurizing pump 88 and 2 nd pressurizing pump 90 by a predetermined value (for example, 10 Hz). Accordingly, in the case where the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 are driven thereafter, the amount of water supplied to the tank 52 increases. After S34, the process advances to S36.

In S36, the control device 150 determines whether or not a stop condition for stopping the microbubble generation operation control is satisfied. In the present embodiment, the stop condition means that the operation control time of the microbubble generation operation control reaches the set time. The operation control time of the microbubble generation operation control is the elapsed time from the start of the microbubble generation operation control. In the water heating device 2 of the present embodiment, when the fine bubble generation operation control is executed alone without being linked to the execution of the hot water injection operation control, the setting time is set to, for example, 10 minutes. In contrast, in the case where the fine bubble generation operation control is executed in association with the execution of the hot water injection operation control, the setting time is set to, for example, 30 minutes. If the stop condition is not satisfied (no), the process returns to S12. If the stop condition is satisfied (yes), the process proceeds to S38.

In S38, the control device 150 executes a stop process for stopping the microbubble generation operation control (see fig. 8). After S38, the process of fig. 7 ends.

As described above, the control device 150 determines whether or not the stop condition is satisfied in the process of S36. However, the control device 150 can also determine whether the stop condition is satisfied in the course of executing the processing of S2 to S34. Further, the control device 150 is configured to stop the processing being executed and execute the processing of S38 (i.e., stop processing) even when it is determined that the stop condition is satisfied during the processing of S2 to S34.

(stop treatment)

As shown in fig. 8, in S52, the control device 150 opens the gas introduction valve 106 when the gas introduction valve 106 is in a closed state. Accordingly, the air is restarted to be introduced into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92.

In S54, the control device 150 determines whether or not the water level of the tank 52 is lower than the boundary water level based ON the presence or absence of the ON signal output from the water level electrode 54. When the water level of the tank 52 is equal to or higher than the boundary water level (no), the process repeats S54. If the water level of the tank 52 is lower than the boundary water level (yes), the process proceeds to S56.

In S56, the control device 150 closes the gas introduction valve 106. Accordingly, the air introduction into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92 is stopped.

In S58, the control device 150 starts the timing of the water level rising time using a built-in timer (not shown).

In S60, the control device 150 determines whether or not the water level rise time started to be counted in S58 exceeds the 2 nd predetermined time (for example, 180 seconds) which is longer than the 1 st predetermined time. When the water level rising time is equal to or less than the 2 nd predetermined time (no), the process repeats S60. If the water level rise time exceeds the 2 nd predetermined time (yes), the process proceeds to S62.

In S62, the control device 150 ends the timing of the water level rising time by a built-in timer (not shown).

In S64, the control device 150 stops the bathtub circulation pump 34, the 1 st pressurizing pump 88, and the 2 nd pressurizing pump 90, and ends the supply of the air-dissolved water from the tank 52 to the bathtub 130.

In S66, the control device 150 stops the tank circulation pump 94. Accordingly, circulation of the water between the tank 52 and the tank circulation path 92 ends. After S66, the process of fig. 8 ends.

In this way, in the stopping process, the control device 150 can stop the micro-bubble generation operation control in a state where the water level electrode 54 is immersed in water. At this time, the water level of the tank 52 at the time point when the process of fig. 8 ends is made higher than the water level of the tank 52 at the time point when the gas introduction valve 106 is opened in S18 of fig. 7, and therefore, even the portion of the water level electrode 54 above the portion immersed in water at the time of normal operation control is immersed in water. Accordingly, the generation of mucus on the water level electrode 54 can be suitably suppressed.

Example 2

The water heater 2 of the present embodiment has substantially the same structure as the water heater 2 of embodiment 1. In the water heating apparatus 2 of the present embodiment, when the micro-bubble generation operation control is performed, the control device 150 performs the processing shown in fig. 9 instead of performing the processing shown in fig. 7. Next, the difference between the processing shown in fig. 9 and the processing shown in fig. 7 will be described.

In the processing shown in fig. 9, when the intake time stored in the memory 152 in S26 exceeds the upper limit intake time (when yes in S28), the processing proceeds to S70. In S70, the control device 150 increases the rotational speed of the tank circulation pump 94 by a predetermined value (for example, 10 Hz). Accordingly, in the case where the tank circulation pump 94 is driven in a state where the gas introduction valve 106 is opened thereafter, the amount of air introduced by the gas introduction mechanism 96 increases. After S70, the process advances to S32.

On the other hand, when the intake time stored in the memory 152 in S26 is lower than the lower limit intake time (in the case of yes in S32), the process proceeds to S72. In S72, control device 150 decreases the rotational speed of tank circulation pump 94 by a predetermined value (e.g., 10 Hz). Accordingly, when the tank circulation pump 94 is driven with the gas introduction valve 106 opened thereafter, the amount of air introduced by the gas introduction mechanism 96 decreases. After S72, the process advances to S36.

In S70 of the process shown in fig. 9, the control device 150 may be configured not to increase the rotation speed of the tank circulation pump 94 when the tank circulation pump 94 is driven with the gas introduction valve 106 closed after that, although the rotation speed of the tank circulation pump 94 is increased when the tank circulation pump 94 is driven with the gas introduction valve 106 opened after that. Similarly, in S72 of the process shown in fig. 9, the control device 150 may be configured not to reduce the rotation speed of the tank circulation pump 94 when the tank circulation pump 94 is driven with the gas introduction valve 106 closed after that, although the rotation speed of the tank circulation pump 94 is reduced when the tank circulation pump 94 is driven with the gas introduction valve 106 opened after that.

Example 3

The water heater 2 of the present embodiment has substantially the same structure as the water heater 2 of embodiment 1. In the water heating apparatus 2 of the present embodiment, when the micro-bubble generation operation control is performed, the control device 150 performs the processing shown in fig. 10 instead of performing the processing shown in fig. 7.

In S82, the control device 150 drives the tank circulation pump 94. Accordingly, water circulates between the tank 52 and the tank circulation path 92.

In S84, control device 150 starts supplying air-dissolved water from tank 52 to bathtub 130. At this time, the control device 150 performs the same processing as S8 of fig. 7.

In S86, the control device 150 determines whether or not the water level of the tank 52 is equal to or higher than the boundary water level based ON the presence or absence of the ON signal output from the water level electrode 54. If the water level of the tank 52 is lower than the boundary water level (no), the process repeats S86. If the water level in the tank 52 is equal to or higher than the boundary water level (yes), the process proceeds to S88.

In S88, the control device 150 opens the gas introduction valve 106. Accordingly, air starts to be introduced into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92.

In S90, the control device 150 starts the timing of the water level lowering time using a built-in timer (not shown).

In S92, the control device 150 determines whether or not the water level drop time counted at S90 exceeds the 3 rd predetermined time (for example, 90 seconds). When the water level drop time is equal to or less than the 3 rd predetermined time (no), the process repeats S92. If the water level drop time exceeds the 3 rd predetermined time (yes), the process proceeds to S94.

In S94, the control device 150 ends the timer (not shown) built-in to count the water level lowering time.

In S96, the control device 150 closes the gas introduction valve 106. Accordingly, the air introduction into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92 is stopped.

In S98, control device 150 starts the timing of the exhaust time using a built-in timer (not shown).

In S100, the control device 150 determines whether or not the water level of the tank 52 is equal to or higher than the boundary water level based ON the presence or absence of the ON signal output from the water level electrode 54. In the case where the water level of the tank 52 is lower than the boundary water level (in the case of no), the process repeats S100. If the water level of the tank 52 is equal to or higher than the boundary water level (yes), the process proceeds to S102.

In S102, the control device 150 opens the gas introduction valve 106. Accordingly, the air is restarted to be introduced into the water flowing through the gas introduction mechanism 96 of the tank circulation path 92.

In S104, control device 150 ends the timing of the exhaust time by a built-in timer (not shown). Further, the control device 150 stores the exhaust time at the end of the timing in the memory 152.

In S106, control device 150 determines whether or not the exhaust time stored in memory 152 in S104 exceeds a predetermined upper limit exhaust time (for example, 120 seconds). If the exhaust time exceeds the upper limit exhaust time (yes), the process proceeds to S108. If the exhaust time is equal to or less than the upper limit exhaust time (if no), the process proceeds to S110.

In S108, control device 150 increases the rotational speeds of 1 st pressurizing pump 88 and 2 nd pressurizing pump 90 by a predetermined value (for example, 10 Hz). Accordingly, in the case where the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 are driven thereafter, the amount of water supplied to the tank 52 increases. After S108, the process advances to S110.

In S110, control device 150 determines whether or not the exhaust time stored in memory 152 in S104 is lower than a predetermined lower limit exhaust time (for example, 60 seconds). If the exhaust time is lower than the lower limit exhaust time (yes), the process proceeds to S112. When the exhaust time is equal to or longer than the lower limit exhaust time (no), the process proceeds to S114.

In S112, control device 150 decreases the rotation speeds of 1 st pressurizing pump 88 and 2 nd pressurizing pump 90 by a predetermined value (for example, 10 Hz). Accordingly, in the case where the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 are driven thereafter, the amount of water supplied to the tank 52 decreases. After S112, the process advances to S114.

In S114, the control device 150 determines whether or not a stop condition for stopping the microbubble generation operation control is satisfied. If the stop condition is not satisfied (no), the process returns to S90. If the stop condition is satisfied (yes), the process proceeds to S116.

In S116, the control device 150 executes a stop process for stopping the microbubble generation operation control (see fig. 8). After S116, the process of fig. 10 ends.

In the above description, the control device 150 determines whether or not the stop condition is satisfied in the process of S114. However, the control device 150 can determine whether the stop condition is satisfied even during execution of the processing of S82 to S112. Further, the control device 150 is configured to stop the processing being executed and execute the processing of S116 (i.e., stop processing) even when it is determined that the stop condition is satisfied during the processing of S82 to S112.

In S108 of the process shown in fig. 10, the control device 150 may decrease the rotation speed of the tank circulation pump 94 by a predetermined value (for example, 10 Hz) instead of increasing the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 by a predetermined value. Accordingly, when the tank circulation pump 94 is driven with the gas introduction valve 106 opened thereafter, the amount of air introduced by the gas introduction mechanism 96 decreases. Similarly, in S112 of the process shown in fig. 10, the control device 150 may increase the rotation speed of the tank circulation pump 94 by a predetermined value (for example, 10 Hz) instead of decreasing the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 by a predetermined value. Accordingly, in the case where the tank circulation pump 94 is driven in a state where the gas introduction valve 106 is opened thereafter, the amount of air introduced by the gas introduction mechanism 96 increases.

(modification)

In the above-described hot water apparatus 2, air is introduced into the tank 52, but carbon dioxide, hydrogen, oxygen, or the like may be introduced into the tank 52 instead of air. In this case, a gas filling tank (not shown) filled with gas may be connected to the gas inlet 104a of the gas introduction path 104.

In the above-described water heating apparatus 2, the water of the set water amount is stored in the bathtub 130 according to the accumulated water amount detected by the water amount sensor 28 in the control of the hot water injection operation. In another embodiment, the water heating device 2 may be configured to, for example, provide a water level sensor capable of detecting the water level of the bathtub 130, and store water of a set water level in the bathtub 130 based on the water level of the bathtub 130 detected by the water level sensor in the hot water injection operation control.

In the above-described water heating apparatus 2, the heat source unit 10 is connected to the faucet 250, and the air pressure dissolving unit 50 is connected to the bathtub 130. In another embodiment, the heat source unit 10 may be connected to another warm utilization site, and the air pressurizing dissolving unit 50 may be connected to another liquid tank.

In the above-described hot water apparatus 2, the gas introduction mechanism 96 is disposed on the tank circulation path 92 upstream of the tank circulation pump 94. In another embodiment, the gas introduction mechanism 96 may be disposed on the tank circulation path 92 on the downstream side of the tank circulation pump 94.

In the above-described water heater 2, the downstream end of the tank circulation path 92 is connected to the tank circuit 74 downstream of the 2 nd booster pump 90. In another embodiment, the downstream end of the tank circulation path 92 may not be connected to the tank circuit 74, or may be provided to the tank 52 independently of the tank circuit 74.

In the above-described water heating apparatus 2, only 1 water level electrode 54 is provided for the water level electrode for detecting the water level in the tank 52. In another embodiment, the water level electrode for detecting the water level in the tank 52 may be provided in plurality.

In the above-described hot water apparatus 2, the user may switch whether or not to perform the operation control of the hot water injection by the remote controller 154, so that the operation control of the generation of the fine bubbles may be performed.

In the above-described water heater 2, when the intake time exceeds the upper limit intake time (yes in S28 of fig. 7 or 9), the control device 150 is configured to decrease the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 by a predetermined value (S30 of fig. 7) or to increase the rotation speed of the tank circulation pump 94 by a predetermined value (S70 of fig. 9). In another embodiment, when the intake time exceeds the upper limit intake time, the control device 150 may be configured to decrease the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 by a predetermined value and increase the rotation speed of the tank circulation pump 94 by a predetermined value. In another embodiment, when the intake time exceeds the upper limit intake time, the control device 150 may be configured to shorten the 1 st predetermined time in S14 in fig. 7 or 9 instead of correcting the rotational speeds of the 1 st pressurizing pump 88, the 2 nd pressurizing pump 90, and the tank circulation pump 94. Accordingly, when it is detected that the water level of the tank 52 is lower than the boundary water level and the water level of the tank 52 is raised (yes in S8), the time for raising the water level of the tank 52 is shortened (the time for repeatedly executing S14).

In the above-described water heater 2, when the intake time is lower than the lower limit intake time (yes in S32 in fig. 7 or 9), the control device 150 is configured to increase the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 by a predetermined value (S34 in fig. 7) or decrease the rotation speed of the tank circulation pump 94 by a predetermined value (S72 in fig. 9). In another embodiment, when the suction time is lower than the lower limit suction time, the control device 150 may be configured to increase the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 by a predetermined value and decrease the rotation speed of the tank circulation pump 94 by a predetermined value. In another embodiment, when the intake time is lower than the lower limit intake time, the control device 150 may be configured to extend the 1 st predetermined time in S14 in fig. 7 or 9 instead of correcting the rotation speeds of the 1 st pressurizing pump 88, the 2 nd pressurizing pump 90, and the tank circulation pump 94. Accordingly, when it is detected that the water level of the tank 52 is lower than the boundary water level and the water level of the tank 52 is raised thereafter (yes in S8), the time for raising the water level of the tank 52 (the time for repeatedly executing S14) is prolonged.

In the above-described water heating device 2, the stop condition for stopping the microbubble generation operation control is that the operation control time of the microbubble generation operation control reaches the set time. In another embodiment, the stop condition may be set up to a time period other than the operation control time period of the microbubble generation operation control. For example, the stop condition may be that the user instructs the end of the microbubble generation operation control via the remote controller 154.

The length of the water level electrode 54 in the water heater 2 may be changed as appropriate. That is, the boundary water level in the water heater 2 may be changed as appropriate.

In the above-described water heater 2, the 1 st predetermined time, the 2 nd predetermined time, the 3 rd predetermined time, the upper limit intake time, the lower limit intake time, the correction value of the rotational speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90, the correction value of the rotational speed of the tank circulation pump 94, and the set time for stopping the operation control of the fine bubbles may be changed as appropriate, respectively.

(correspondence relation)

As described above, in 1 or more embodiments, the water heater 2 (an example of a microbubble generator) includes the tank 52, the tank circuit 74 (an example of a tank supply path), the 1 st booster pump 88, the 2 nd booster pump 90 (an example of a booster pump), the tank outlet 64, the 1 st bathtub water path 62, the bathtub adapter 132 (an example of a tank discharge path), the microbubble generating nozzle 142, the tank circulation path 92, the tank circulation pump 94, the gas introduction mechanism 96, the water level electrode 54 (an example of a liquid level electrode), and the control device 150, wherein the tank 52 pressurizes the dissolved air (an example of a gas) with water (an example of a liquid); the tank circuit 74 (an example of a tank supply path) supplies water to the tank 52; the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 (examples of pressurizing pumps) are provided in the tank circuit 74; the tank outlet 64, the 1 st bathtub water path 62, and the bathtub adapter 132 (an example of a tank discharge path) discharge pressurized air-dissolved water from the tank 52 to the bathtub 130 (an example of a tank); the fine air bubble generating nozzle 142 is provided in the bathtub adapter 132, and generates fine air bubbles by depressurizing the water in which air is dissolved under pressure; the tank circulation path 92 is provided independently of the tank outlet 64, the 1 st bathtub water path 62, and the bathtub adapter 132, and supplies water from the outflow port 92a connected to the tank 52 to the water supply port 74a (an example of an inflow port) connected to the tank 52; the tank circulation pump 94 is provided in the tank circulation path 92; the gas introduction mechanism 96 is provided in the tank circulation path 92; the water level electrode 54 (an example of a liquid level electrode) can detect whether the water level of the tank 52 is equal to or higher than a boundary water level (an example of a predetermined liquid level). The gas introduction mechanism 96 has a venturi 102 (an example of a pressure reducing portion), a gas introduction port 104a, and a gas introduction valve 106, wherein the venturi 102 (an example of a pressure reducing portion) allows water to pass through under reduced pressure; the gas inlet 104a introduces air by negative pressure of water in the venturi 102; the gas introduction valve 106 opens and closes the gas introduction port 104a. The control device 150 is capable of executing the fine air bubble generation operation control, which is: the 1 st booster pump 88 and the 2 nd booster pump 90 are driven to supply water from the tank circuit 74 to the tank 52 under pressure, and water in which air is dissolved under pressure is supplied from the tank 52 to the bathtub 130 through the tank outlet 64, the 1 st bathtub water channel 62, and the bathtub adapter 132. The control device 150 drives the tank circulation pump 94 to circulate the water in the tank 52 through the tank circulation path 92, thereby supplying the air introduced through the gas introduction port 104a to the tank 52, and controls the opening and closing operation of the gas introduction valve 106 based ON the presence or absence of the ON signal (an example of information about whether or not the tank liquid level detected by the liquid level electrode is equal to or higher than a predetermined liquid level) output from the water level electrode 54.

In 1 or more embodiments, the water heating device 2 (an example of a microbubble generation device) includes a tank 52, a tank circuit 74 (an example of a tank supply path), a 1 st booster pump 88, a 2 nd booster pump 90 (an example of a booster pump), a tank outlet 64, a 1 st bathtub water path 62, a bathtub adapter 132 (an example of a tank discharge path), a microbubble generation nozzle 142, a tank circulation path 92, a tank circulation pump 94, a gas introduction mechanism 96, a single water level electrode 54 (an example of a liquid level electrode), and a control device 150, wherein the tank 52 pressurizes dissolved air (an example of a gas) with water (an example of a liquid); the tank circuit 74 (an example of a tank supply path) supplies water to the tank 52; the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 (examples of pressurizing pumps) are provided in the tank circuit 74; the tank outlet 64, the 1 st bathtub water path 62, and the bathtub adapter 132 (an example of a tank discharge path) discharge pressurized air-dissolved water from the tank 52 to the bathtub 130 (an example of a tank); the fine air bubble generating nozzle 142 is provided in the bathtub adapter 132, and generates fine air bubbles by depressurizing the water in which air is dissolved under pressure; the tank circulation path 92 is provided independently of the tank outlet 64, the 1 st bathtub water path 62, and the bathtub adapter 132, and supplies water from the outflow port 92a connected to the tank 52 to the water supply port 74a (an example of an inflow port) connected to the tank 52; the tank circulation pump 94 is provided in the tank circulation path 92; the gas introduction mechanism 96 is provided in the tank circulation path 92; the single water level electrode 54 (an example of a liquid level electrode) can detect whether the water level of the tank 52 is equal to or higher than a boundary water level (an example of a predetermined liquid level). The gas introduction mechanism 96 has a venturi 102 (an example of a pressure reducing portion), a gas introduction port 104a, and a gas introduction valve 106, wherein the venturi 102 (an example of a pressure reducing portion) allows water to pass through under reduced pressure; the gas inlet 104a introduces air by negative pressure of water in the venturi 102; the gas introduction valve 106 opens and closes the gas introduction port 104a. The control device 150 is capable of executing the fine air bubble generation operation control, which is: the 1 st booster pump 88 and the 2 nd booster pump 90 are driven to supply water from the tank circuit 74 to the tank 52 under pressure, and water in which air is dissolved under pressure is supplied from the tank 52 to the bathtub 130 through the tank outlet 64, the 1 st bathtub water channel 62, and the bathtub adapter 132. The control device 150 drives the tank circulation pump 94 to circulate the water in the tank 52 through the tank circulation path 92, thereby supplying the air introduced through the air introduction port 104a to the tank 52, and controls the opening and closing operation of the air introduction valve 106 based ON the presence or absence of the ON signal (an example of information about whether or not the tank liquid level detected by the liquid level electrode is equal to or higher than a predetermined liquid level) output from the single water level electrode 54.

According to the above configuration, the control device 150 is configured to control the opening and closing operation of the gas introduction valve 106 according to the presence or absence of the ON signal outputted from the 1 water level electrode 54. Therefore, the amount of information relating to the water level of the tank 52 can be reduced, and thus the rapidity of the judgment process relating to the opening and closing of the gas introduction valve 106 can be ensured.

In 1 or more embodiments, the control device 150 closes the gas introduction valve 106 when the water level electrode 54 detects that the water level of the tank 52 is lower than the boundary water level in the state where the gas introduction valve 106 is opened during execution of the fine bubble generation operation control, keeps the gas introduction valve 106 closed until the 1 st predetermined time elapses after the gas introduction valve 106 is closed, and opens the gas introduction valve 106 after the 1 st predetermined time elapses.

In the water heating device 2, water droplets scattered from the water surface of the tank 52 adhere to the water level electrode 54, and accordingly, the water level electrode 54 may generate mucus. However, when mucus is generated by the water level electrode 54, the water level of the tank 52 may be erroneously detected. For example, the water heating device 2 has a lower water level electrode and an upper water level electrode, and when the control device 150 performs control of the opening and closing operation of the gas introduction valve 106 so that the water level of the tank 52 changes between the lower water level and the upper water level, the upper water level electrode is hardly immersed in water. Therefore, the upper water level electrode cannot suppress the generation of mucus, and may erroneously detect the water level of the tank 52. According to the above configuration, in the process of executing the micro-bubble generation operation control, by frequently immersing the water level electrode 54 in water, the generation of the mucus of the water level electrode 54 can be suppressed. Therefore, erroneous detection of the water level of the tank 52 can be suppressed.

In 1 or more embodiments, the control device 150 performs the following processing in performing the microbubble generation operation control: the elapsed time from when the gas introduction valve 106 is opened and closed to when the water level electrode 54 detects that the water level of the tank 52 is lower than the divided water level and the gas introduction valve 106 is closed is determined as the suction time, and when the suction time exceeds the upper limit suction time, the rotational speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 when the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 are driven thereafter are reduced.

It is assumed that the amount of water supplied to the tank 52 is excessive or the amount of air introduced by the gas introduction mechanism 96 is too small when the intake time is too long. The amount of water supplied to the tank 52 increases as the rotation speeds of the 1 st and 2 nd pressurizing pumps 88, 90 increase, and the amount of water supplied to the tank 52 decreases as the rotation speeds of the 1 st and 2 nd pressurizing pumps 88, 90 decrease. According to the above configuration, when the intake time exceeds the upper limit intake time, that is, when the intake time is too long, the amount of water supplied to the tank 52 can be reduced by reducing the rotation speeds of the 1 st booster pump 88 and the 2 nd booster pump 90, thereby shortening the intake time.

In 1 or more embodiments, the control device 150 performs the following processing in performing the microbubble generation operation control: the elapsed time from when the gas introduction valve 106 is opened and closed to when the water level electrode 54 detects that the water level of the tank 52 is lower than the divided water level and the gas introduction valve 106 is closed is determined as the suction time, and when the suction time is lower than the lower limit suction time, the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 when the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90 are driven thereafter are reduced.

It is assumed that the amount of water supplied to the tank 52 is too small or the amount of air introduced by the gas introduction mechanism 96 is too large when the intake time is too short. According to the above configuration, when the intake time is less than the lower limit intake time, that is, when the intake time is too short, the amount of water supplied to the tank 52 can be increased by increasing the rotation speeds of the 1 st pressurizing pump 88 and the 2 nd pressurizing pump 90, so that the intake time can be prolonged.

In 1 or more embodiments, the control device 150 performs the following processing in performing the microbubble generation operation control: the elapsed time from when the gas introduction valve 106 is opened and closed to when the gas introduction valve 106 is closed due to the detection by the water level electrode 54 that the water level of the tank 52 is lower than the divided water level is determined as the intake time, and when the intake time exceeds the upper limit intake time, the rotation speed of the tank circulation pump 94 when the tank circulation pump 94 is driven with the gas introduction valve 106 opened thereafter is increased.

It is assumed that the amount of water supplied to the tank 52 is excessive or the amount of air introduced by the gas introduction mechanism 96 is too small when the intake time is too long. In addition, in the state where the gas introduction valve 106 is opened, the higher the rotational speed of the tank circulation pump 94, the more the amount of air introduced by the gas introduction mechanism 96 increases, and the lower the rotational speed of the tank circulation pump 94, the less the amount of air introduced by the gas introduction mechanism 96 decreases. According to the above configuration, when the intake time exceeds the upper limit intake time, that is, when the intake time is too long, the amount of air introduced by the gas introduction mechanism 96 can be increased by increasing the rotation speed of the tank circulation pump 94, thereby achieving a reduction in the intake time.

In 1 or more embodiments, the control device 150 performs the following processing in performing the microbubble generation operation control: the elapsed time from when the gas introduction valve 106 is opened and closed to when the gas introduction valve 106 is closed due to the detection by the water level electrode 54 that the water level of the tank 52 is lower than the divided water level is determined as the suction time, and when the suction time is lower than the lower limit suction time, the rotation speed of the tank circulation pump 94 when the tank circulation pump 94 is determined in the state where the gas introduction valve 106 is opened is increased.

It is assumed that the amount of water supplied to the tank 52 is too small or the amount of air introduced by the gas introduction mechanism 96 is too large when the intake time is too short. According to the above configuration, when the intake time is less than the lower limit intake time, that is, when the intake time is too short, the amount of air introduced by the gas introduction mechanism 96 can be reduced by reducing the rotation speed of the tank circulation pump 94, thereby realizing an extension of the intake time.

In 1 or more embodiments, the control device 150 performs the following processing in performing the microbubble generation operation control: it is possible to determine whether or not a stop condition for stopping the microbubble generation operation control is satisfied, and execute a stop process for stopping the microbubble generation operation control when the stop condition is satisfied. The control device 150 performs the following processing when executing the stop processing: when the gas introduction valve 106 is opened while the 1 st pressurizing pump 88, the 2 nd pressurizing pump 90, and the tank circulation pump 94 are driven, and when the water level electrode 54 detects that the water level of the tank 52 is lower than the boundary water level while the gas introduction valve 106 is opened, the gas introduction valve 106 is closed, and the gas introduction valve 106 is kept closed until the 2 nd predetermined time, which is a time longer than the 1 st predetermined time, has elapsed since the gas introduction valve 106 was closed, and after the 2 nd predetermined time has elapsed, the 1 st pressurizing pump 88, the 2 nd pressurizing pump 90, and the tank circulation pump 94 are stopped to stop the microbubble generation operation control.

According to the above configuration, the micro-bubble generation operation control can be stopped in a state where the water level electrode 54 is immersed in water. Accordingly, the generation of mucus on the water level electrode 54 can be suppressed, and thus erroneous detection of the water level of the tank 52 can be suppressed. In addition, according to the above configuration, when the microbubble generation operation control is stopped, the portion of the water level electrode 54 above the portion immersed in water during the normal operation control is also immersed in water. Therefore, the generation of mucus in the water level electrode 54 can be more suitably suppressed.

In 1 or more embodiments, the control device 150 performs the following processing in performing the microbubble generation operation control: when the water level of the tank 52 is detected to be equal to or higher than the boundary water level by the water level electrode 54 in a state where the gas introduction valve 106 is closed, the gas introduction valve 106 is opened, the gas introduction valve 106 is kept in an opened state until the 3 rd predetermined time elapses from the opening of the gas introduction valve 106, and the gas introduction valve 106 is closed after the 3 rd predetermined time elapses.

For example, when the water heater 2 has a lower water level electrode and an upper water level electrode, and the control device 150 controls the opening and closing operation of the gas introduction valve 106 so that the water level of the tank 52 changes between the lower water level and the upper water level, the length of the lower water level electrode needs to be relatively long. In this case, the weight of the entire water heating apparatus 2 may be increased. According to the above configuration, the length of the water level electrode 54 can be made relatively short. Accordingly, the entire water heater 2 can be reduced in weight.

In 1 or more embodiments, the liquid is water. The sink is a bath tub 130 for a user to bathe.

According to the above configuration, in the water heating device 2 that generates fine bubbles in the water of the bathtub 130 for bathing by the user, the amount of information on the water level of the tank 52 can be reduced, and thus the rapidity of the judgment process regarding the opening and closing of the gas introduction valve 106 can be ensured.

The embodiments have been described in detail above, but these embodiments are merely examples and do not limit the scope of the technical means. The technology described in the claims includes various modifications and changes to the specific examples shown above. The technical elements described in the present specification or the drawings are useful in technology alone or in various combinations, and are not limited to the combinations described in the claims at the time of application. In addition, the technology illustrated in the present specification or the drawings can achieve a plurality of objects at the same time, and achieving one of the objects itself has technical usefulness.

Claims

1. A micro-bubble generating device is characterized in that,

comprises a tank, a tank supply path, a booster pump, a tank discharge path, a fine bubble generation nozzle, a tank circulation path, a tank circulation pump, a gas introduction mechanism, a liquid level electrode, and a control device,

The storage tank pressurizes and dissolves the gas in the liquid;

the tank supply path supplies the liquid to the tank;

the pressurizing pump is provided in the tank supply path;

the tank discharge path discharging the liquid in which the gas is dissolved under pressure from the tank to a liquid tank;

the fine bubble generation nozzle is provided in the tank discharge path, and depressurizes the liquid in which the gas is dissolved under pressure to generate fine bubbles;

the tank circulation path and the tank discharge path are provided separately for conveying the liquid from an outflow port connected to the tank to an inflow port connected to the tank;

the tank circulation pump is provided to the tank circulation path;

the gas introduction mechanism is provided in the tank circulation path;

the liquid level electrode is capable of detecting whether the liquid level of the storage tank is above a prescribed liquid level,

the gas introduction mechanism has a pressure reducing portion, a gas introduction port, and a gas introduction valve, wherein,

the pressure reducing section passing the liquid under reduced pressure;

the gas introduction port introduces the gas by a negative pressure of the liquid in the pressure reducing portion;

the gas introduction valve opens and closes the gas introduction port,

The control device is capable of executing a fine bubble generation operation control, which means: driving the pressurizing pump to supply the liquid from the tank supply path to the tank under pressure and to supply the liquid in which the gas is dissolved under pressure from the tank to the liquid tank through the tank discharge path,

the control means performs the following processing in the course of performing the fine bubble generation operation control:

driving the tank circulation pump to circulate the liquid in the tank circulation path, thereby supplying the gas introduced through the gas introduction port to the tank;

and controlling opening and closing operations of the gas introduction valve based on information about whether or not the liquid level of the tank detected by the liquid level electrode is equal to or higher than a predetermined liquid level.

2. The micro-bubble generating apparatus according to claim 1, wherein,

when the liquid level of the storage tank is detected to be lower than the prescribed liquid level by the liquid level electrode in a state where the gas introduction valve is opened, the gas introduction valve is closed,

Maintaining the gas introduction valve in a closed state during a period from closing the gas introduction valve to the lapse of the 1 st predetermined time,

the gas introduction valve is opened after the 1 st prescribed time has elapsed.

3. The micro-bubble generating apparatus according to claim 2, wherein,

determining an elapsed time from when the gas introduction valve is opened in the closed state to when the gas introduction valve is closed by detecting that the liquid level of the tank is lower than the predetermined liquid level by the liquid level electrode,

in the case where the suction time exceeds the upper limit suction time, the rotation speed of the pressurizing pump when the pressurizing pump is driven thereafter is reduced.

4. The micro-bubble generating apparatus according to claim 2 or 3, wherein,

In the case where the suction time is lower than the lower limit suction time, the rotation speed of the pressurizing pump at the time of driving the pressurizing pump thereafter is increased.

5. The micro-bubble generating apparatus according to any one of claims 2 to 4, wherein,

determining an elapsed time from when the gas introduction valve in the closed state is opened to when the liquid level of the tank is detected to be lower than the predetermined liquid level by the liquid level electrode and the gas introduction valve is closed,

when the intake time exceeds the upper limit intake time, the rotational speed of the tank circulation pump is increased when the tank circulation pump is driven in a state where the gas introduction valve is opened thereafter.

6. The micro-bubble generating apparatus according to any one of claims 2 to 5, wherein,

When the intake time is less than the lower limit intake time, the rotational speed of the tank circulation pump is reduced when the tank circulation pump is driven in a state where the gas introduction valve is opened thereafter.

7. The micro-bubble generating apparatus according to any one of claims 2 to 6, wherein,

it is possible to determine whether or not a stop condition for stopping the microbubble generation operation control is satisfied,

executing a stop process for stopping the microbubble generation operation control in the case where the stop condition is satisfied,

the following processing is performed when the stop processing is performed:

the gas introduction valve is opened in a state where the pressurizing pump and the tank circulation pump are driven,

when the liquid level of the storage tank is detected to be lower than the predetermined liquid level by the liquid level electrode in a state where the gas introduction valve is opened, the gas introduction valve is closed,

maintaining the gas introduction valve in a closed state during a period from closing the gas introduction valve to a time longer than the 1 st predetermined time, that is, a 2 nd predetermined time,

After the predetermined time of the 2 nd step, the pressurizing pump and the tank circulation pump are stopped to stop the fine bubble generation operation control.

8. The micro-bubble generating apparatus according to claim 1, wherein,

when the liquid level of the storage tank is detected to be equal to or higher than the predetermined liquid level by the liquid level electrode in a state where the gas introduction valve is closed, the gas introduction valve is opened,

maintaining the gas introduction valve in an open state during a period from opening the gas introduction valve to the lapse of a 3 rd predetermined time,

and closing the gas introduction valve after the 3 rd prescribed time has elapsed.

9. A micro-bubble generating device is characterized in that,

comprises a tank, a tank supply path, a booster pump, a tank discharge path, a fine bubble generation nozzle, a tank circulation path, a tank circulation pump, a gas introduction mechanism, a single liquid level electrode, and a control device,

the storage tank pressurizes and dissolves the gas in the liquid;

the tank supply path supplies the liquid to the tank;

The pressurizing pump is provided in the tank supply path;

the fine bubble generation nozzle is provided in the tank discharge path, and is configured to depressurize the liquid in which the gas is dissolved under pressure to generate fine bubbles;

the tank circulation pump is provided to the tank circulation path;

the gas introduction mechanism is provided in the tank circulation path;

the single level electrode is capable of detecting whether the liquid level of the tank is above a prescribed level,

the pressure reducing section passing the liquid under reduced pressure;

the gas introduction valve opens and closes the gas introduction port,

The control means is capable of executing the following processing in executing the fine bubble generation operation control:

driving the tank circulation pump to circulate the liquid in the tank circulation path, thereby supplying the gas introduced through the gas introduction port to the tank,

and controlling the opening and closing operation of the gas introduction valve based on information about whether or not the liquid level of the tank detected by the single liquid level electrode is equal to or higher than a predetermined liquid level.

10. The micro-bubble generating apparatus according to any one of claims 1 to 9, wherein,

the liquid is water and the liquid is water,

the liquid tank is a bathtub for a user to bath.