Water discharge system, wash system, and hand washing device

Abstract

A water discharge system (10) comprises: a water storage tank (11) which stores stored water; a modification means (40) which modifies the stored water; a supply path (15) through which the stored water is supplied via the modification means (40) from the water storage tank (11) to a water discharge unit (14) which discharges the stored water that has passed through the modification means (40); a pump (16) which sends the stored water from the water storage tank (11) to the supply path (15); and a circulation flow path (18) which is connected to the water storage tank (11) on the upstream side of the water discharge unit (14) along the supply path (15).

Description

Water discharge system, washbasin system, and handwasher

[0001] The present disclosure relates to a water discharge system, a washbasin system, and a handwasher.

[0002] Patent Document 1 discloses a handwashing device that purifies wastewater used for handwashing and reuses it as washing water.

[0003] Japanese Unexamined Patent Publication No. 2022-14999

[0004] This handwashing device has a sensor unit including a pressure sensor, a flow rate sensor, an EC / temperature sensor, and the like. However, a configuration provided with such a sensor unit tends to be expensive.

[0005] The present disclosure has been completed in view of the circumstances described above, and aims to provide a water discharge system and a washbasin system that can purify wastewater and reuse it as washing water with a simple configuration.

[0006] Patent Document 1 discloses a handwashing device that purifies wastewater used for handwashing, stores the purified water as stored water in a water storage tank, and reuses the stored water as washing water.

[0007] When this handwashing device does not discharge water from the faucet for a long period of time, there is a concern that the stored water in the water storage tank may deteriorate. For this reason, a technique for suppressing deterioration of stored water regardless of the presence or absence of water discharge from the faucet is desired.

[0008] The present disclosure has been completed in view of the circumstances described above, and aims to provide a water discharge system and a handwasher that can suppress deterioration of stored water regardless of the presence or absence of water discharge.

[0009] A water discharge system according to a first disclosure includes: a water storage tank that stores stored water; a reforming unit that reforms the stored water; a supply path that supplies the stored water from the water storage tank via the reforming unit to a water discharge unit that discharges the stored water that has passed through the reforming unit; a pump that sends the stored water from the water storage tank to the supply path; and a circulation flow path that connects to the water storage tank at a position upstream of the water discharge unit in the supply path.

[0010] The washbasin system of the second disclosure comprises the water discharge system of the first disclosure and a bowl for receiving the stored water discharged from the water discharge section.

[0011] The handwashing basin of the third disclosure comprises the water discharge system of the first disclosure and a sink that receives the water discharged from the water discharge unit.

[0012] This is a schematic diagram of a washbasin system equipped with a water discharge system according to Embodiment 1. This is a time chart showing an example of the operation of the water discharge system according to Embodiments 1 and 4. This is a schematic diagram of a washbasin system equipped with a water discharge system according to Embodiment 2. This is a schematic diagram of a washbasin system equipped with a water discharge system according to Embodiment 3. This is a time chart showing an example of the operation of the water discharge system according to Embodiment 3. This is a schematic diagram showing the hardware configuration of the control unit. This is a schematic diagram of a handwashing basin equipped with a water discharge system according to Embodiment 4. This is a flowchart showing an example of the control of the circulation operation in the water discharge system according to Embodiment 4. This is a flowchart showing an example of the control of the washing mode in the water discharge system according to Embodiment 4. This is a flowchart showing an example of the control of the circulation operation in the water discharge system according to Embodiment 5. This is a flowchart showing an example of the control of the circulation operation in the water discharge system according to Embodiment 6. This is a schematic diagram of a handwashing basin equipped with a water discharge system according to Embodiment 7. This is a flowchart showing an example of the control of the circulation operation in the water discharge system according to Embodiment 7.

[0013] First, embodiments of this disclosure will be listed and described. Any combination of the following embodiments, without causing any inconsistency, is also included as a form for carrying out the invention.

[0014] The water discharge system of the present disclosure comprises: (1) a water storage tank for storing stored water; a modification means for modifying the stored water; a supply path for supplying the stored water from the water storage tank, via the modification means, to a water discharge section for discharging the stored water that has passed through the modification means; a pump for sending the stored water from the water storage tank to the supply path; and a circulation path connected to the water storage tank upstream of the water discharge section in the supply path. With this configuration, the water discharge system is expected to have the effect of preventing the stored water from stagnating and suppressing the growth of bacteria by flowing the stored water through the circulation path.

[0015] [2] In the water discharge system described in [1] above, the modification means includes a filter for removing at least one of bacteria and impurities from the stored water, and an ultraviolet sterilization means for sterilizing the stored water by irradiating it with ultraviolet light.

[0016] [3] In the water discharge system described in [2] above, the stored water circulates through at least the water storage tank, the pump, the supply channel, the filter, the branching section located upstream of the water discharge section in the supply channel, and the circulation channel. With this configuration, it is possible to remove at least one of the bacteria and impurities contained in the stored water by simply circulating the stored water, and to reuse the stored water as washing water.

[0017] [4] In the water discharge system described in [2] above, the stored water is constantly circulated through at least the water storage tank, the pump, the supply channel, the filter, the branching section located upstream of the water discharge section in the supply channel, and the circulation channel. This configuration makes it easier to maintain a high water quality for the stored water.

[0018] [5] In the water discharge system described in either [3] or [4] above, the ultraviolet sterilization means is provided between the branching section and the water discharge section in the supply path. With this configuration, it is possible to irradiate all of the stored water that passes through the water discharge section with ultraviolet light.

[0019] [6] In the water discharge system described in either [3] or [4] above, the ultraviolet sterilization means is provided upstream of the branching point in the supply path. With this configuration, viruses contained in the stored water stored in the water storage tank can be inactivated by the ultraviolet sterilization means.

[0020] [7] In the water discharge system described in any of [2] to [6] above, a detection unit for detecting an object is provided, and the ultraviolet sterilization means is driven when the detection unit detects the object, and stops driving when the detection unit no longer detects the object, or when a predetermined time has elapsed since the detection unit stopped detecting the object. With this configuration, the ultraviolet sterilization means is driven when an object is near the water discharge system or when the object is facing the water outlet of the water discharge unit, and the ultraviolet sterilization means is not driven when at least the object is not near the water discharge system or is not facing the water outlet of the water discharge unit. Therefore, compared to the case where the ultraviolet sterilization means is always driven, it is expected that the deterioration of the ultraviolet sterilization means will be slowed down and its lifespan extended.

[0021] [8] In the water discharge system described in [7], which directly or indirectly references any of [3] to [6] above, the branching section switches to a flow-permitting state that allows the flow of stored water from the water storage tank to the water discharge section when the detection unit detects the object. This configuration makes it possible to discharge water from the water discharge section when an object is near the water discharge system or when an object is placed facing the water outlet of the water discharge section.

[0022] [9] In the water discharge system described in either [7] or [8] above, the pump is driven when the detection unit detects the object. With this configuration, water can be discharged from the water discharge unit when the object is near the water discharge system or when the object is facing the water outlet of the water discharge unit, so that water can be discharged from the water discharge unit only when necessary.

[0023]

[10] The water discharge system described in any of [1] to [9] above is provided separately from the circulation channel and includes a circulation path for circulating the stored water stored in the water storage tank. With this configuration, it is expected that circulating the stored water in the circulation path will have the effect of suppressing the growth of bacteria in the stored water.

[0024]

[11] The water discharge system described in any of [2] to [9] above includes a measuring unit that measures the cumulative flow rate of the stored water that has passed through the filter, and a notification unit that notifies the user when the cumulative flow rate exceeds a threshold. With this configuration, it is possible to realize a system that notifies the user of when it is time to replace the filter based on the cumulative flow rate measured by the measuring unit.

[0025]

[12] In the water discharge system described in any of [2] to [9] above, when a detection unit that detects an object located away from the water discharge unit detects the object, the water discharge unit discharges the stagnant water that has accumulated in the supply channel located upstream of the ultraviolet sterilization means. With this configuration, the discharge of stagnant water in the supply channel can be started as soon as the detection unit detects an object located away from the water discharge unit, and as a result, when an object is facing the water discharge port of the water discharge unit, the stored water that has just passed through the filter from the water storage tank can be discharged.

[0026]

[13] The water discharge system described in [1] above includes a control unit that controls the flow of the stored water, and the control unit performs a circulation operation at a predetermined timing to circulate the stored water in the water storage tank through the circulation channel. With this configuration, the water discharge system can maintain the stored water in a clean state by passing it through the reforming means at a predetermined timing.

[0027]

[14] In the water discharge system described in

[13] above, the control unit performs the circulation operation from the time after stopping the discharge of water from the water discharge unit until a predetermined time has elapsed. With this configuration, the water discharge system can reliably maintain the stored water in a clean state.

[0028]

[15] In the water discharge system described in

[14] above, the predetermined time is the time it is assumed that bacteria will begin to proliferate in the stored water. With this configuration, the water discharge system can be expected to have an effect of efficiently suppressing the proliferation of bacteria.

[0029]

[16] In the water discharge system described in any of

[13] to

[15] above, the control unit performs the circulation operation at a time set by the user. With this configuration, the water discharge system is easy to use because it can circulate the stored water according to the user's lifestyle.

[0030]

[17] In the water discharge system described in

[13] above, the control unit performs the circulation operation continuously after stopping the discharge of water from the water discharge unit. With this configuration, the operating noise when the stored water is discharged into the circulation channel can be made less noticeable compared to when the stored water is discharged into the circulation channel by itself.

[0031]

[18] In the water discharge system described in

[13] above, the control unit stops the water discharge from the water discharge unit for the first time during the day, up to 24 hours after a predetermined time, and then continuously performs the circulation operation. With this configuration, the water discharge system can make the operating noise when the stored water is discharged into the circulation channel less noticeable and can maintain the stored water in a clean state, compared to when the stored water is discharged into the circulation channel by itself.

[0032]

[19] In the water discharge system described in any of

[13] to

[16] above, the control unit prohibits the execution of the circulation operation until a specific time has elapsed from the time the execution of the circulation operation is completed. With this configuration, the water discharge system can avoid performing the circulation operation unnecessarily.

[0033]

[20] In the water discharge system described in

[13] above, the control unit performs the circulation operation if no water is discharged from the water discharge unit between the time it is assumed that bacteria will begin to proliferate in the stored water and the time elapsed since the water discharge unit was stopped. With this configuration, the water discharge system can protect the modification means by minimizing the circulation operation and suppress the generation of operating noise when not in use.

[0034]

[21] In the water discharge system described in any of

[13] to

[16] and

[19] above, the control unit can change the flow rate of the stored water per unit time flowing through the circulation channel during the circulation operation. With this configuration, for example, reducing the flow rate of the water discharge system can be expected to reduce the operating noise of the pump. Increasing the flow rate can be expected to complete the circulation of the stored water in a shorter period of time. In other words, the water discharge system can set the driving force of the pump according to the user's wishes.

[0035]

[22] In the water discharge system described in any of

[13] to

[21] above, the control unit has a cleaning mode in which the stored water containing the cleaning component is flowed through both the supply passage and the circulation passage. With this configuration, the water discharge system can keep the passage through which the stored water flows clean.

[0036]

[23] In the water discharge system described in any of [1] and

[13] to

[22] above, the modification means includes a first filter for collecting dirt and a second filter for collecting dirt smaller than that of the first filter, and the circulation path includes a first circulation path connected to the water storage tank upstream of the second filter in the supply path and downstream of the first filter, and a second circulation path connected to the water storage tank downstream of the second filter in the supply path. With this configuration, the water discharge system can reduce the amount of stored water that flows to the second filter compared to the first filter by selecting either the first circulation path or the second circulation path as the path through which the stored water flows. For example, if the second filter is more expensive or has a shorter lifespan than the first filter, it is possible to extend the lifespan of the second filter and reduce the frequency of replacement of the second filter.

[0037]

[24] The washbasin system of the second disclosure comprises a water discharge system as described in any of [1] to

[23] above, and a bowl for receiving the stored water discharged from the water discharge section. With this configuration, by circulating the stored water in the water discharge system, it is possible to prevent the stored water from stagnating and to suppress the growth of bacteria.

[0038]

[25] The handwashing sink of the third disclosure comprises a water discharge system as described in any of [1] to

[23] above, and a sink that receives the water discharged from the water discharge unit. With this configuration, the handwashing sink is expected to have the effect of suppressing the growth of bacteria in the stored water.

[0039] <Embodiment 1> Embodiment 1, which embodies the washbasin system 1 equipped with the water discharge system 10 according to the present disclosure, will be described with reference to Figures 1 and 2. The X-axis and Y-axis shown in each figure represent the front-back direction and the up-down direction, respectively. In the X-axis and Y-axis, the positive direction of each axis is defined as the front and up, respectively.

[0040] The washbasin system 1 can be installed, for example, in the entrance hall or beside the bed in a living room. If the washbasin system 1 is installed in the entrance hall, the user can wash their hands using the water supply system 10 when returning home, or wash their pet's paws in the entrance hall when returning home after walking their pet. If the washbasin system 1 is installed beside the bed, the user can wash their hands while in bed. In short, the washbasin system 1 is for home use.

[0041] [Configuration of the washbasin system] The washbasin system 1 comprises a water dispensing system 10 and a bowl 30. As shown in Figure 1, the water dispensing system 10 comprises a water storage tank 11 for storing stored water, a supply passage 15, a pump 16, a water discharge section 14, a water treatment means 40, a branching section 17, a circulation passage 18, a measuring section 20, a notification section 21, a detection section 19, a circulation path 22, and a control section 23. The water treatment means 40 comprises a filter 12 for removing bacteria and impurities from the stored water and an ultraviolet sterilization means 13 for sterilizing the stored water by irradiating it with ultraviolet light. The water treatment means 40 treats the stored water.

[0042] The water storage tank 11 stores, for example, approximately 5 liters of tap water as stored water. The water storage tank 11 is detachable from the cabinet C in which it is housed. The supply passage 15 is a path that supplies stored water from the water storage tank 11 to the water discharge section 14, which will be described later. One end of the supply passage 15 is located above the bottom wall of the water storage tank 11. The other end of the supply passage 15 is connected to the upstream end of the water discharge section 14. The pump 16 is installed in the middle of the supply passage 15. When the pump 16 is driven, it sends stored water from the water storage tank 11 to the supply passage 15. The pump 16 is controlled, for example, by the control unit 23.

[0043] The water outlet 14 has the function of discharging stored water from its own water outlet 14A toward the bowl 30, which will be described later, via the supply passage 15.

[0044] The filter 12 includes a first filter 12A, a second filter 12B, and a third filter 12C. The first filter 12A collects impurities such as dust that have been washed off from an object such as a human body and passed through the hair catcher 30A. The first filter 12A is disposed at a position upstream of the pump 16 in the supply passage 15. For the second filter 12B, for example, an activated carbon filter is used. The second filter 12B collects impurities such as dust that have passed through the first filter 12A (that could not be completely collected by the first filter 12A). The second filter 12B is disposed at a position downstream of the pump 16 in the supply passage 15. For the third filter 12C, for example, a hollow fiber filter or a reverse osmosis membrane (RO membrane) is used. The third filter 12C collects impurities such as dust and bacteria that have passed through the second filter 12B (that could not be completely collected by the second filter 12B). The third filter 12C is disposed at a position downstream of the second filter 12B in the supply passage 15. In the third filter 12C, countless pores having an outer diameter smaller than the size of bacteria that can propagate in the stored water are formed. That is, the filter 12 sequentially captures impurities starting from the largest size, and finally captures the smallest size of impurities.

[0045] For the branch portion 17, for example, a known three-way valve is used. The branch portion 17 is provided at a position upstream of the water discharge portion 14 and downstream of the filter 12 in the supply passage 15. The branch portion 17 is controlled by a control unit 23 to be described later. The circulation flow passage 18 extends from the branch portion 17 and is connected to the middle of an inflow passage 30B to be described later. The circulation flow passage 18 is connected to the water storage tank 11 via the inflow passage 30B.

[0046] The ultraviolet sterilization means 13 includes a flow passage through which stored water passes, and an ultraviolet LED (Light Emitting Diode) disposed so as to be capable of irradiating the stored water in the flow passage with ultraviolet light. The ultraviolet LED is controlled by the control unit 23. The ultraviolet sterilization means 13 is provided at a position downstream of the branch portion 17 in the supply passage 15 and upstream of the water discharge portion 14 (that is, between the branch portion 17 and the water discharge portion 14 in the supply passage 15).

[0047] For the measurement unit 20, for example, a known integrated flow meter is used. The measurement unit 20 is provided at a position on the downstream side of the filter 12 in the supply passage 15 and on the upstream side of the branch portion 17. The measurement unit 20 measures the integrated flow rate of the stored water that is sent to the supply passage 15 by the pump 16 and passes through the filter 12. The measurement unit 20 outputs an integrated value Ad corresponding to the measured integrated flow rate to the control unit 23.

[0048] For the notification unit 21, for example, an LED is used. The notification unit 21 is controlled by the control unit 23. For example, the notification unit 21 lights up when a lighting signal is input from the control unit 23, and turns off when no lighting signal is input. The notification unit 21 is housed in the cabinet C of the water discharge system 10. For example, a maintenance window is formed in the cabinet C, and a user can check the state of the notification unit 21 by looking through the maintenance window (not shown).

[0049] For the detection unit 19, for example, a known infrared sensor is used. The detection unit 19 is provided, for example, in the vicinity of the bowl 30 so as to be exposed facing forward. When the detection unit 19 detects that an object such as a user has approached the front of itself (the front of the water discharge system 10) (in other words, detects a user (object) at a position distant from the water discharge unit 14), it outputs an approach signal As to the control unit 23. The detection unit 19 does not output the approach signal As when there is no object such as a user in front of itself (the front of the water discharge system 10).

[0050] The circulation path 22 is provided separately from the circulation flow passage 18. A circulation pump 22A is provided in the middle of the circulation path 22. When driven, the circulation pump 22A sends the stored water from the water storage tank 11 to the circulation path 22. Thereby, the stored water stored in the water storage tank 11 circulates through the circulation path 22. The circulation pump 22A is controlled by, for example, the control unit 23. The circulation pump 22A is preferably smaller in size and lower in power consumption than the pump 16. For example, the circulation pump 22A is constantly driven by the control unit 23. Thereby, the stored water in the water storage tank 11 constantly circulates through the circulation path 22. The stored water constantly circulates (moves) through the circulation path 22, which makes it less likely to stagnate and suppresses bacterial growth.

[0051] The control unit 23 is configured, for example, by a microcomputer. Specifically, as shown in Figure 6, the control unit 23 includes a processor 23A such as a CPU, and a memory 23B such as ROM or RAM. The control unit 23 controls the operation of the branching unit 17, the pump 16, the circulation pump 22A, the ultraviolet LED of the ultraviolet sterilization means 13, and the notification unit 21 based on the proximity signal As input from the detection unit 19 and the integrated value Ad input from the measurement unit 20 by executing a program 23C stored in the memory 23B on the processor 23A. The memory 23B of the control unit 23 stores a threshold value Th for comparison with the integrated value Ad.

[0052] The bowl 30 is formed, for example, in the shape of an open box facing upwards and is provided at the upper end of the cabinet C. An outlet 30C is formed in the bottom wall of the bowl 30. A hair catcher 30A is provided in the bowl 30 as a filter, connected to the outlet 30C. The bowl 30 is connected to the water storage tank 11 via an inlet passage 30B. The bowl 30 receives the stored water discharged from the water discharge section 14 and allows the received stored water to flow into the water storage tank 11 via the outlet 30C and the inlet passage 30B.

[0053] [Example of operation of the water discharge system] For example, as shown in Figure 2, at time T0, when the integrated value Ad is less than the threshold Th and the proximity signal As is not input (Lo in Figure 2), this is the first state. In the first state, the control unit 23 sets the state of the branching section 17 to a flow suppression state. In the flow suppression state, the branching section 17 connects the supply path 15 and the circulation path 18 so that stored water can flow through, and suppresses the flow of stored water to the water discharge section 14. At time T1, which is a predetermined timing when the first state is in place and the branching section 17 is in the flow suppression state, the control unit 23 drives the pump 16 to send stored water from the water storage tank 11 to the supply path 15 and executes a circulation operation to pass it through the filter 12. For example, in the circulation operation, the control unit 23 repeatedly passes the stored water through the filter 12 up to an amount approximately four times (20 L) the amount of stored water stored in the water storage tank 11 (5 L). For example, the control unit 23 executes the circulation operation once every 24 hours. During the circulation operation, the stored water circulates through the storage tank 11, pump 16, supply path 15, filter 12, branching section 17, and circulation path 18. While the circulation operation is running, the cumulative value Ad from the measuring unit 20 increases.

[0054] The circulating operation is completed at time T2, a predetermined time after time T1. At time T3, after time T2, the cumulative value Ad is less than the threshold Th, and the proximity signal As is input (the detection unit 19 has detected a user (object), which is Hi in Figure 2), and the system switches to a second state. Then, the control unit 23 switches the state of the branching unit 17 to a flow-allowed state. In the flow-allowed state, the branching unit 17 disconnects the connection between the supply path 15 and the circulation path 18 so that stored water does not flow between them, and allows the flow of stored water from the water storage tank 11 to the water discharge unit 14. At the same time, the control unit 23 lights up the ultraviolet LED of the ultraviolet sterilization means 13. In other words, the ultraviolet sterilization means 13 is activated when the detection unit 19 detects a user (object). When the control unit 23 is in the second state and the branching section 17 is in a flow-permitting state, it drives the pump 16 to send stored water from the water storage tank 11 to the discharge section 14 and discharges it from the discharge port 14A. Here, the discharge section 14 is not provided with an on / off valve. The discharge section 14 is a cylinder with a flow path formed from one end to the other. Therefore, when the pump 16 is started to drive when the branching section 17 is in a flow-permitting state, the discharge section 14 immediately starts discharging water from the discharge port 14A. In other words, the pump 16 is driven when the detection unit 19 detects a user (object). As the stored water passes through the ultraviolet sterilization means 13, it is irradiated with ultraviolet light by an ultraviolet LED. This inactivates viruses contained in the stored water.

[0055] For example, at time T3, when the control unit 23 detects a user (object) located away from the water discharge unit 14 using the detection unit 19, it causes the water discharge unit 14 to discharge the stagnant water, which is the stored water that remains in the supply channel 15 located upstream of the ultraviolet sterilization means 13. In other words, the water discharge system 10 discharges water from the water discharge unit 14 so that all the stagnant water is expelled from the supply channel 15 before the user extends their hand below the water outlet 14A of the water discharge unit 14, and when the user extends their hand below the water outlet 14A of the water discharge unit 14, the stored water that has just been sent from the water storage tank 11 to the supply channel 15 and passed through the filter 12 is discharged from the water outlet 14A. At this time, the water discharge unit 14 discharges the stored water that has passed through the filter 12 and the ultraviolet sterilization means 13. The supply channel 15 supplies stored water from the water storage tank 11 to the water discharge unit 14 via the modification means 40 (filter 12 and ultraviolet sterilization means 13). In the second state, while stagnant water and stored water are being discharged from the water discharge section 14, the cumulative value Ad from the measurement section 20 increases.

[0056] Then, at time T4, when the system switches from the second state to the first state (from a state where the proximity signal As is input to a state where it is not input), the control unit 23 switches the state of the branching section 17 from a flow-allowed state to a flow-restricted state. At the same time, the control unit 23 stops the operation of the pump 16 and the ultraviolet LED. In other words, the pump 16 and the ultraviolet sterilization means 13 stop operating when the detection unit 19 no longer detects a user (object).

[0057] For example, if the circulation operation is performed (between time T1 and time T2 in Figure 2) and the system switches from the first state to the second state (from a state where the proximity signal As is not input to a state where it is input), the control unit 23 stops the circulation operation, switches the state of the branching section 17 from a flow suppression state to a flow allowance state, and drives the pump 16 and ultraviolet LED to discharge the stored water from the discharge section 14. Subsequently, when the system switches from the second state back to the first state (the state where the proximity signal As is not input), the control unit 23 stops driving the pump 16 and ultraviolet LED and switches the state of the branching section 17 from a flow allowance state to a flow suppression state. After that, the control unit 23 restarts the circulation operation after a predetermined time shorter than 24 hours has elapsed.

[0058] From time T4 onward, the system repeatedly switches between the first and second states, causing the discharge and stopping of stored water. Then, at time T5, if the accumulated value Ad exceeds the threshold Th while stored water is being discharged from the discharge unit 14, the system switches to the third state. In the third state, regardless of whether or not an approach signal As is input, the state of the branching unit 17 is switched from a flow-allowed state to a flow-restricted state. Also, in the third state, the control unit 23 stops the operation of the pump 16 and the ultraviolet LED, regardless of whether or not an approach signal As is input. Simultaneously with the switch to the third state (at time T5), the control unit 23 lights up the notification unit 21.

[0059] In the third state, the control unit 23 restricts water discharge from the water discharge unit 14 regardless of the proximity signal As. When the user realizes that no stored water is discharged from the water discharge unit 14 even when approaching the water discharge system 10 after time T5, they check whether the notification unit 21 inside the cabinet C is lit through a maintenance window (not shown) provided in the cabinet C. When the user realizes that the notification unit 21 is lit, they clean the water storage tank 11 and store fresh tap water as stored water, replace the filter 12 with a new one, and reset the accumulated value Ad accumulated in the measurement unit 20 (for example, to 0). This allows the user to resume using the water discharge system 10.

[0060] For example, the control unit 23 always drives the circulation pump 22A provided in the circulation path 22, regardless of the first, second, and third states. As a result, the water stored in the water storage tank 11 is constantly circulating through the circulation path 22. By constantly circulating (moving) the water through the circulation path 22, the stored water is less likely to stagnate, and the growth of bacteria is suppressed.

[0061] As described above, the water discharge system 10 of Embodiment 1 includes a water storage tank 11 for storing stored water, a filter 12 (modification means 40) for removing bacteria and impurities from the stored water, an ultraviolet sterilization means 13 (modification means 40) for sterilizing the stored water by irradiating it with ultraviolet light, a water discharge section 14 for discharging the stored water that has passed through the filter 12 and the ultraviolet sterilization means 13, a supply passage 15 for supplying stored water from the water storage tank 11 to the water discharge section 14 that discharges the stored water that has passed through the modification means 40 (filter 12 and ultraviolet sterilization means 13) and the modification means 40, a pump 16 for sending stored water from the water storage tank 11 to the supply passage 15, and a circulation passage 18 extending from a branching section 17 located upstream of the water discharge section 14 in the supply passage 15 and connected to the water storage tank 11. The stored water circulates at least through the water storage tank 11, the portion of the supply passage 15 upstream of the branching section 17, and the circulation passage 18. This configuration is expected to prevent the stored water from stagnating by circulating it, thereby suppressing bacterial growth.

[0062] The stored water circulates through the storage tank 11, pump 16, supply channel 15, filter 12, branching section 17 located upstream of the discharge section 14 in the supply channel 15, and circulation channel 18. With this configuration, it is possible to remove bacteria and impurities contained in the stored water and reuse the stored water as washing water through a simple configuration of circulating the stored water.

[0063] The ultraviolet sterilization means 13 is installed between the branching section 17 and the water discharge section 14 in the supply passage 15. With this configuration, it is possible to irradiate all of the stored water that passes through the water discharge section 14 with ultraviolet light.

[0064] The water discharge system 10 is equipped with a detection unit 19 that detects a user (object). The ultraviolet sterilization means 13 is activated when the detection unit 19 detects a user (object) and stops activating when the detection unit 19 no longer detects a user (object). With this configuration, the ultraviolet sterilization means 13 is activated when a user (object) is near the water discharge system 10, and not activated when a user (object) is not near the water discharge system 10. Compared to the case where the ultraviolet sterilization means 13 is always activated, this configuration is expected to slow down the deterioration of the ultraviolet sterilization means 13 and extend its lifespan.

[0065] When the detection unit 19 detects a user (object), the branching unit 17 switches to a flow-permitting state, allowing the flow of stored water from the water storage tank 11 to the water discharge unit 14. This configuration makes it possible to discharge water from the water discharge unit 14 when a user (object) is near the water discharge system 10.

[0066] The pump 16 is activated when the detection unit 19 detects a user (object). With this configuration, water can be discharged from the discharge unit 14 when the user (object) is near the water discharge system 10, so water can be discharged from the discharge unit 14 only when necessary.

[0067] The water discharge system 10 is provided separately from the circulation channel 18 and includes a circulation path 22 for circulating the stored water in the water storage tank 11. With this configuration, it is expected that circulating the stored water in the circulation path 22 will have the effect of suppressing the growth of bacteria in the stored water.

[0068] The water discharge system 10 includes a measuring unit 20 that measures the cumulative flow rate of stored water that has passed through the filter 12, and a notification unit 21 that notifies the user when the cumulative value Ad (cumulative flow rate) exceeds a threshold Th. With this configuration, it is possible to realize a system that notifies the user of when it is time to replace the filter 12 based on the cumulative flow rate measured by the measuring unit 20.

[0069] The water discharge system 10, when a detection unit 19 detects a user (object) located away from the water discharge unit 14, discharges stagnant water accumulated in the supply channel 15 located upstream of the ultraviolet sterilization means 13 from the water discharge unit 14. With this configuration, the discharge of stagnant water in the supply channel 15 can be started as soon as the detection unit 19 detects a user (object) located away from the water discharge unit 14. As a result, when a part of the user's body (object) faces the water outlet 14A of the water discharge unit 14, stored water that has just passed through the filter 12 from the water storage tank 11 can be discharged.

[0070] The washbasin system 1 comprises a water discharge system 10 and a bowl 30 that receives the stored water discharged from the water discharge section 14. With this configuration, by circulating the stored water, it is expected that the stored water will not stagnate and the growth of bacteria will be suppressed.

[0071] <Embodiment 2> A washbasin system 2 equipped with a water discharge system 100 according to Embodiment 2, which embodies the present disclosure, will be described with reference to Figure 3. The washbasin system 2 according to Embodiment 2 differs from Embodiment 1 in that a three-way valve is not used in the branching section 117 of the water discharge system 100, there is no circulation path, and a water discharge pump 25 is provided at a position between the connection point with the circulation path 18 in the supply path 15 and the ultraviolet sterilization means 13. Components similar to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted.

[0072] The washbasin system 2 comprises a water discharge system 100 and a bowl 30. As shown in Figure 3, the water discharge system 100 comprises a water storage tank 11, a supply passage 15, a pump 16, a water discharge section 14, a filter 12 (modification means 40), a branching section 117, a circulation passage 18, an ultraviolet sterilization means 13 (modification means 40), a measurement section 20, a notification section 21, a detection section 19, a control section 23, and a water discharge pump 25.

[0073] The branching section 117 is configured as a part where the circulation channel 18 is directly connected to the supply channel 15. The water discharge pump 25 is positioned in the supply channel 15 between the branching section 117 and the ultraviolet sterilization means 13.

[0074] For example, the control unit 23 always drives the pump 16 regardless of the first, second, and third states. As a result, the water stored in the water storage tank 11 constantly circulates through the water storage tank 11, pump 16, supply passage 15, filter 12, branching section 117, and circulation passage 18. In other words, the control unit 23 always drives the pump 16 regardless of the first, second, and third states to send the stored water from the water storage tank 11 to the supply passage 15 and continues to perform the circulation operation of passing it through the filter 12.

[0075] For example, when switching from the first state to the second state (from a state where the proximity signal As is not input to a state where it is input), the control unit 23 drives the water discharge pump 25 and the ultraviolet LED of the ultraviolet sterilization means 13. As a result, a portion of the stored water flowing from the supply path 15 to the circulation path 18 is sent to the water discharge section 14 by the driven water discharge pump 25 and discharged from the water outlet 14A. In other words, the water discharge pump 25 is driven when the detection unit 19 detects a user (object). When switching from the second state to the first state (from a state where the proximity signal As is input to a state where it is not input), the control unit 23 stops driving the water discharge pump 25 and the ultraviolet LED.

[0076] For example, when the system switches to the third state (where the accumulated value Ad is equal to or greater than the threshold Th), the control unit 23 stops driving the water discharge pump 25 and the ultraviolet LED, regardless of whether or not an approach signal As is input. The pump 16 may also be stopped when the system is in the third state.

[0077] In the water discharge system 100, the stored water constantly circulates through the storage tank 11, pump 16, supply channel 15, filter 12, branch section 117 located upstream of the water discharge section 14 in the supply channel 15, and circulation channel 18. This configuration makes it easy to maintain a high water quality for the stored water.

[0078] <Embodiment 3> A washbasin system 3 equipped with a water discharge system 200 according to Embodiment 3, which embodies the present disclosure, will be described with reference to Figures 4 and 5. The washbasin system 3 according to Embodiment 3 differs from Embodiment 1 in that an operating lever 14B is provided on the water discharge section 14 of the water discharge system 200. Components similar to those in Embodiment 1 are denoted by the same reference numerals and their descriptions are omitted.

[0079] The washbasin system 3 comprises a water dispensing system 200 and a bowl 30. As shown in Figure 4, the water dispensing unit 14 is provided with an operating lever 14B. By operating the operating lever 14B, the state of the water dispensing unit 14 can be switched between a water dispensing state and a water-stopped state.

[0080] The water discharge section 14 is initially set to a shut-off state by the operating lever 14B. For example, as shown in Figure 5, at time T10, the cumulative value Ad is less than the threshold Th, and the proximity signal As is input (the detection unit 19 detects a user (object), which is Hi in Figure 5), switching to a second state. Then, the control unit 23 switches the state of the branching section 17 from a flow suppression state to a flow allowance state. At the same time, the control unit 23 drives the pump 16 and the ultraviolet LED of the ultraviolet sterilization means 13. At time T10, since the water discharge section 14 is set to a shut-off state by the operating lever 14B, the branching section 17 is in a flow allowance state, and even if the pump 16 is driven, the stored water is not discharged.

[0081] At time T11, the operating lever 14B is operated, and the state of the water discharge unit 14 switches from the stopped state to the discharge state. As a result, the water discharge unit 14 starts discharging the stored water. At time T12, the operating lever 14B is operated again, and the state of the water discharge unit 14 switches from the discharge state to the stopped state, and the water discharge unit 14 stops discharging the stored water. Then, at time T13, when the user moves away from the water discharge system 200 and the state switches from the second state to the first state (from the state where the proximity signal As is input to the state where it is not input), the control unit 23 switches the state of the branching unit 17 from the flow-allowed state to the flow-restricted state, and also stops the operation of the pump 16 and the ultraviolet LED.

[0082] From time T13 onward, the system repeatedly switches between the first and second states, causing the discharge and stopping of stored water. Then, at time T14, the operating lever 14B is operated, switching the state of the discharge unit 14 from the stopped state to the discharge state, and the discharge unit 14 begins to discharge stored water. From time 14 onward, as the stored water passes through the measurement unit 20, the value of the accumulated value Ad gradually increases, and at time T15, when the accumulated value Ad exceeds the threshold Th, the system switches to the third state. In the third state, regardless of whether an approach signal As is input or the state of the discharge unit 14, the state of the branching unit 17 is switched to the flow suppression state. Also, in the third state, regardless of whether an approach signal As is input or the state of the discharge unit 14, the control unit 23 stops the operation of the pump 16 and the ultraviolet LED. In the third state, the control unit 23 restricts water discharge from the water discharge unit 14, regardless of whether or not an approach signal As is input and the state of the water discharge unit 14. The control unit 23 lights up the notification unit 21 at the same time (time T15) as the switch to the third state.

[0083] This disclosure is not limited to the embodiments described above and in the drawings, and the technical scope of this disclosure also includes, for example, the following embodiments.

[0084] Unlike Embodiment 1 described above, the detection unit may not be provided in the sink, but rather in a configuration where the detection unit is provided adjacent to the spout of the water outlet. In this case, when a part of the user's body (object) is placed below the spout, a proximity signal is output from the detection unit. Based on the input of the proximity signal, the control unit switches the state of the branching unit from a flow restriction state to a flow allow state and drives the pump and the ultraviolet LED. When a part of the user's body (object) moves away from below the spout and the output of the proximity signal from the detection unit stops, the control unit switches the state of the branching unit from a flow allow state to a flow restriction state and stops driving the pump and the ultraviolet LED based on the input of the proximity signal. With this configuration, the ultraviolet sterilization means is driven when a part of the user's body (object) is facing the spout of the water outlet, and not driven when it is not facing the spout of the water outlet. Therefore, compared to the case where the ultraviolet sterilization means is always driven, it is expected that the deterioration of the ultraviolet sterilization means will be slowed down and its lifespan extended.

[0085] Unlike the above embodiment 3, the configuration may include a water discharge detection unit that detects objects located below the water discharge outlet adjacent to the outlet, instead of an operating lever for the water discharge unit. When the control unit receives a detection signal from the water discharge detection unit indicating that an object has been detected, it opens the solenoid valve provided in the water discharge unit, and closes the solenoid valve when no detection signal is received. For example, when the cumulative value is below a threshold and the control unit switches to a second state in which an approach signal is received, it switches the state of the branching unit from a flow restriction state to a flow allowable state and drives the pump and the ultraviolet LED of the ultraviolet sterilization means. Subsequently, when the user places their hand below the water discharge outlet, the solenoid valve of the water discharge unit 14 opens and the stored water is discharged. When the user removes their hand from below the water discharge outlet, the solenoid valve of the water discharge unit 14 closes and the discharge of stored water stops. Subsequently, when the user moves away from the water discharge system and the system switches from the second state to the first state, the control unit switches the state of the branching section from a flow-allowed state to a flow-restricted state, and stops the operation of the pump and the ultraviolet LED. With this configuration, the ultraviolet LED can be driven before the stored water is discharged from the water discharge section, thereby enhancing the virus-inactivating effect of the ultraviolet LED before the stored water is discharged from the water discharge section.

[0086] Unlike the above embodiment, the amount of water stored in the storage tank may be more or less than 5 liters.

[0087] Unlike the above embodiment, the measurement unit may be configured to count the number of times the stored water switches from a stationary state to a flowing state. For example, the measurement unit outputs a count value corresponding to the counted number to the control unit. The upper limit of the allowable number of times is stored in the control unit's memory as a threshold, and the control unit compares the count value with the threshold value. When the control unit determines that the count value is equal to or greater than the threshold value, it switches to the third state.

[0088] Unlike the above embodiment, the notification unit may be configured to use a buzzer. Specifically, when the cumulative value exceeds a threshold in the third state, the control unit causes the notification unit to emit a sound. Alternatively, a light bulb or a liquid crystal display element (LCD panel) may be used as the notification unit.

[0089] Unlike Embodiment 1 described above, the configuration may not include a circulation channel, circulation path, and branching section. In this case, the control unit drives the pump at a predetermined timing when in the first state (when no proximity signal is input) to send the stored water to the supply channel, pass it through the filter, and perform the circulation operation for a predetermined time. In other words, the stored water circulates through the storage tank, pump, supply channel, filter, ultraviolet sterilization means, and discharge section at a predetermined timing. The ultraviolet sterilization means may be driven during the circulation operation. Then, in the second state when a user approaches the discharge system and an proximity signal is output from the detection unit, the control unit drives the pump and ultraviolet sterilization means to discharge the stored water from the discharge section. In this embodiment, the discharge system discharges water from the discharge section so that all stagnant water is removed from the supply channel before the user extends their hand below the discharge spout, and when the user extends their hand below the discharge spout, the stored water that has just been sent from the storage tank to the supply channel and passed through the filter is discharged from the discharge section.

[0090] Unlike the above embodiment, the ultraviolet sterilization means may be provided upstream of the branching point in the supply path. In this case, the control unit drives the pump at a predetermined timing when the branching point is in a flow-restricted state in the first state to perform a circulation operation to send stored water from the water storage tank to the supply path and pass it through the filter. The ultraviolet LED is lit while the circulation operation is being performed. In other words, the stored water circulates through the water storage tank, pump, supply path, filter, ultraviolet sterilization means, branching point, and circulation path at a predetermined timing. This makes it possible to inactivate viruses contained in the stored water stored in the water storage tank by the ultraviolet sterilization means.

[0091] Unlike the above embodiment, the control unit may be configured to stop the operation of the pump and ultraviolet LED after a predetermined time has elapsed since the switch from the second state to the first state (from a state in which an approach signal is input to a state in which it is not input). Even if water discharge continues for a while after the switch from the second state to the first state, the stored water will circulate and be reused, so it will not be wasted.

[0092] Unlike Embodiment 1 described above, the pump provided in the supply path may be kept running at all times, and the branching section may be switched to a flow-allowing state when an approach signal is input from the detection unit, and to a flow-restricting state when no approach signal is input from the detection unit. In this case, when the branching section is in a flow-restricting state, the stored water constantly circulates through the storage tank, pump, supply path, filter, branching section, and circulation path.

[0093] Unlike the above embodiment, the first filter may be positioned downstream of the pump in the supply line. Alternatively, the first filter may be omitted. Furthermore, the first to third filters may be housed in a single case. Additionally, only filters for removing impurities may be provided, or only filters for removing bacteria may be provided. Furthermore, when capturing impurities by size, they may be captured in a different order than in the above embodiment.

[0094] Unlike the above embodiment, an ultraviolet lamp may be used as the ultraviolet sterilization means.

[0095] Unlike the above embodiment, a sink may be used instead of a bowl.

[0096] Unlike the above embodiment, the detection unit may be arranged so that it is exposed facing forward on the outer surface of the water discharge unit.

[0097] Unlike the above embodiment, the circulation channel may be connected directly to the water storage tank without going through the inlet channel.

[0098] Unlike the above embodiment, the stored water may be circulated through the storage tank, the portion of the supply channel upstream of the branching point, the branching point, and the circulation channel. In this case, the filter and measuring unit are placed in the portion of the supply channel downstream of the branching point.

[0099] <Embodiment 4> Embodiment 4, which embodies the handwashing station 4 equipped with the water discharge system 300 according to the present disclosure, will be described with reference to Figures 2 and 6 to 9. The X-axis and Y-axis shown in each figure represent the front-back direction and the up-down direction, respectively. In the X-axis and Y-axis, the positive direction of each axis is defined as the front and up, respectively.

[0100] The handwashing basin 4 can be installed, for example, in the entrance hall or beside the bed in a living room. If the handwashing basin 4 is installed in the entrance hall, the user can wash their hands using the water dispensing system 300 when returning home, or wash their pet's paws in the entrance hall when returning home after walking their pet. If the handwashing basin 4 is installed beside the bed, the user can wash their hands while in bed. In short, the handwashing basin 4 is for home use.

[0101] [Configuration of the handwashing sink] The handwashing sink 4 comprises a water discharge system 300 and a sink 31. As shown in Figure 7, the water discharge system 300 comprises a water storage tank 11 for storing stored water, a supply passage 15, a pump 16, a water discharge section 14, a water treatment means 40, a branching section 17, a circulation passage 18, a measuring section 20, a notification section 21, a detection section 19, a control section 23, and an operation section 24. The water treatment means 40 comprises a filter 12 for removing bacteria and impurities from the stored water and an ultraviolet sterilization means 13 for sterilizing the stored water by irradiating it with ultraviolet light.

[0102] The water storage tank 11 stores, for example, approximately 5 liters of tap water as stored water. The water storage tank 11 is detachable from the cabinet C in which it is housed. The supply passage 15 is a path that supplies stored water from the water storage tank 11 to the water discharge section 14, which will be described later. One end of the supply passage 15 is located above the bottom wall of the water storage tank 11. The other end of the supply passage 15 is connected to the upstream end of the water discharge section 14. The pump 16 is installed in the middle of the supply passage 15. When the pump 16 is driven, it sends stored water from the water storage tank 11 to the supply passage 15. The pump 16 is controlled, for example, by the control unit 23.

[0103] The water outlet 14 has the function of discharging stored water from its own outlet 14A toward the sink 31, which will be described later, via the supply passage 15.

[0104] The filter 12 includes a first filter 12A, a second filter 12B, and a third filter 12C. The first filter 12A collects impurities such as dust that have been washed away from objects such as the human body and passed through the hair catcher 30A. The first filter 12A is an activated carbon filter. The first filter 12A is located upstream of the pump 16 in the supply path 15. The second filter 12B is an activated carbon filter. The second filter 12B collects impurities such as dust that have passed through the first filter 12A (and were not collected by the first filter 12A). The second filter 12B is located downstream of the pump 16 in the supply path 15. The third filter 12C is a hollow fiber filter or a reverse osmosis membrane (RO membrane). The third filter 12C collects impurities such as dust and bacteria that have passed through the second filter 12B (and were not collected by the second filter 12B). The third filter 12C is positioned downstream of the second filter 12B in the supply channel 15. The third filter 12C has countless pores with an outer diameter smaller than the size of bacteria that can proliferate in the stored water. In other words, the filter 12 captures impurities in order from the largest to the smallest size.

[0105] The ultraviolet sterilization means 13 includes a channel through which the stored water passes, and an ultraviolet LED (Light Emitting Diode) positioned to irradiate the stored water in the channel with ultraviolet light. The ultraviolet LED is controlled by the control unit 23. The ultraviolet sterilization means 13 is located downstream of the branching section 17 in the supply channel 15 and upstream of the water discharge section 14 (i.e., between the branching section 17 and the water discharge section 14 in the supply channel 15).

[0106] The branching section 17 is a known three-way valve. The branching section 17 is located upstream of the discharge section 14 in the supply passage 15 and downstream of the filter 12. The branching section 17 is controlled by a control unit 23, which will be described later. The circulation passage 18 extends from the branching section 17 and connects to the middle of the inflow passage 30B, which will be described later. The circulation passage 18 is connected to the water storage tank 11 via the inflow passage 30B.

[0107] The measuring unit 20 is a known integrated flow meter. The measuring unit 20 is located downstream of the filter 12 and upstream of the branching section 17 in the supply path 15. The measuring unit 20 measures the integrated flow rate of the stored water that has been sent to the supply path 15 by the pump 16 and passed through the filter 12. The measuring unit 20 outputs an integrated value Ad corresponding to the measured integrated flow rate to the control unit 23.

[0108] The notification unit 21 is an LED. The notification unit 21 is controlled by the control unit 23. When a lighting signal is input from the control unit 23, the notification unit 21 lights up, and when no lighting signal is input, it turns off. The notification unit 21 is housed in the cabinet C of the water discharge system 300. A maintenance window is formed in the cabinet C, and the user can check the status of the notification unit 21 by looking through the maintenance window (not shown).

[0109] The detection unit 19 is a known infrared sensor. The detection unit 19 is located near the sink 31 and is exposed facing forward. When the detection unit 19 detects that an object such as a user is approaching in front of it (in front of the water discharge system 300) (in other words, it detects a user (object) at a position away from the water discharge unit 14), it outputs a proximity signal As to the control unit 23. The detection unit 19 does not output a proximity signal As if there is no object such as a user in front of it (in front of the water discharge system 300).

[0110] The control unit 23 is composed of a microcomputer. Specifically, as shown in Figure 6, the control unit 23 includes a processor 23A such as a CPU, and a memory 23B such as ROM or RAM. The control unit 23 controls the operation of the branching unit 17, the pump 16, the ultraviolet LED of the ultraviolet sterilization means 13, and the notification unit 21 based on the proximity signal As input from the detection unit 19 and the integrated value Ad input from the measurement unit 20 by executing a program 23C stored in the memory 23B on the processor 23A. The memory 23B of the control unit 23 stores a threshold value Th for comparison with the integrated value Ad. The control unit 23 is configured to acquire the current time by known methods such as a radio clock, atomic clock, or GPS.

[0111] The control unit 24 has a configuration in which multiple switches are provided on the surface of an electrical circuit board. As shown in Figure 7, the control unit 24 is electrically connected to the control unit 23. When a user operates a switch on the control unit 24, the control unit 24 outputs an operation signal corresponding to the operated switch to the control unit 23. The control unit 23 can set the degree of force of the pump 16 drive and the time to start the circulation operation, which will be described later, according to the operation signal input from the control unit 24.

[0112] The sink 31 is formed in the shape of an open box and is located at the upper end of the cabinet C. An outlet 30C is formed in the bottom wall of the sink 31. A hair catcher 30A is provided in the sink 31 as a filter, connected to the outlet 30C. The sink 31 is connected to the water storage tank 11 via an inlet passage 30B. The sink 31 receives the stored water discharged from the water outlet 14 and flows the received stored water into the water storage tank 11 via the outlet 30C and the inlet passage 30B.

[0113] [Example of operation of the water discharge system] The user can change the driving force of the pump 16 when performing the circulation operation by operating the switch on the control unit 24. The circulation operation is the operation of circulating the stored water through the storage tank 11, pump 16, supply path 15, filter 12, branching section 17, and circulation path 18. Based on the operation signal from the control unit 24 operated by the user, the control unit 23 can change the driving force of the pump 16 during the circulation operation, thereby changing the flow rate of stored water per unit time flowing through the circulation path 18. The flow rate of stored water per unit time in the pump 16 can be changed between approximately 2 L / min and 8 L / min.

[0114] The user can set a reference time for executing the cyclic operation by operating a switch on the control unit 24. When the current time reaches the reference time set by the user, the control unit 23 starts executing the cyclic operation.

[0115] As shown in Figure 2, at time T0, the state in which the integrated value Ad is less than the threshold Th and the proximity signal As is not input (Lo in Figure 2) is the first state. In the first state, the control unit 23 sets the state of the branching section 17 to a flow suppression state. In the flow suppression state, the branching section 17 connects the supply path 15 and the circulation path 18 so that stored water can flow, and suppresses the flow of stored water to the discharge section 14. In the first state, when the branching section 17 is in the flow suppression state, when the current time reaches the reference time (time T1) set by the user, the control unit 23 drives the pump 16 to send stored water from the water storage tank 11 to the supply path 15 and starts the execution of a circulation operation that passes it through the filter 12. In the circulation operation, the control unit 23 repeatedly passes the stored water through the filter 12 up to an amount approximately four times (20 L) the amount of stored water stored in the water storage tank 11 (5 L). During the circulation operation, the stored water circulates through the storage tank 11, pump 16, supply path 15, filter 12, branching section 17, and circulation path 18. While the circulation operation is running, the cumulative value Ad from the measuring unit 20 increases.

[0116] The circulating operation is completed at time T2, a predetermined time after time T1. At time T3, after time T2, the cumulative value Ad is less than the threshold Th, and the proximity signal As is input (the detection unit 19 has detected a user (object), which is Hi in Figure 2), and the system switches to a second state. Then, the control unit 23 switches the state of the branching unit 17 to a flow-allowed state. In the flow-allowed state, the branching unit 17 disconnects the connection between the supply path 15 and the circulation path 18 so that stored water does not flow between them, and allows the flow of stored water from the water storage tank 11 to the water discharge unit 14. At the same time, the control unit 23 lights up the ultraviolet LED of the ultraviolet sterilization means 13. In other words, the ultraviolet sterilization means 13 is activated when the detection unit 19 detects a user (object). When the control unit 23 is in the second state and the branching section 17 is in a flow-permitting state, it drives the pump 16 to send stored water from the water storage tank 11 to the discharge section 14 and discharges it from the discharge port 14A. Here, the discharge section 14 is not provided with an on / off valve. The discharge section 14 is a cylinder with a flow path formed from one end to the other. Therefore, when the pump 16 is started to drive when the branching section 17 is in a flow-permitting state, the discharge section 14 immediately starts discharging water from the discharge port 14A. In other words, the pump 16 is driven when the detection unit 19 detects a user (object). As the stored water passes through the ultraviolet sterilization means 13, it is irradiated with ultraviolet light by an ultraviolet LED. This inactivates viruses contained in the stored water.

[0117] For example, at time T3, when the control unit 23 detects a user (object) located away from the water discharge unit 14 using the detection unit 19, it causes the water discharge unit 14 to discharge the stagnant water, which is the stored water that remains in the supply channel 15 located upstream of the ultraviolet sterilization means 13. In other words, the water discharge system 300 discharges water from the water discharge unit 14 so that all the stagnant water is drained from the supply channel 15 before the user extends their hand below the water outlet 14A of the water discharge unit 14, and when the user extends their hand below the water outlet 14A of the water discharge unit 14, the stored water that has just been sent from the water storage tank 11 to the supply channel 15 and passed through the filter 12 is discharged from the water outlet 14A. At this time, the water discharge unit 14 discharges the stored water that has passed through the filter 12 and the ultraviolet sterilization means 13. The supply channel 15 supplies stored water from the water storage tank 11 to the water discharge unit 14 via the modification means 40 (filter 12 and ultraviolet sterilization means 13). In the second state, while stagnant water and stored water are being discharged from the water discharge section 14, the cumulative value Ad from the measurement section 20 increases.

[0118] Then, at time T4, when the system switches from the second state to the first state (from a state where the proximity signal As is input to a state where it is not input), the control unit 23 switches the state of the branching section 17 from a flow-allowed state to a flow-restricted state. At the same time, the control unit 23 stops the operation of the pump 16 and the ultraviolet LED. In other words, the pump 16 and the ultraviolet sterilization means 13 stop operating when the detection unit 19 no longer detects a user (object).

[0119] If the circulation operation is in progress (between time T1 and time T2 in Figure 2) and the system switches from the first state to the second state (from a state where the proximity signal As is not input to a state where it is input), the control unit 23 stops the circulation operation, switches the state of the branching section 17 from a flow suppression state to a flow allowance state, and drives the pump 16 and ultraviolet LED to discharge the stored water from the discharge section 14. Subsequently, when the system switches from the second state back to the first state (the state where the proximity signal As is not input), the control unit 23 stops driving the pump 16 and ultraviolet LED and switches the state of the branching section 17 from a flow allowance state to a flow suppression state. After that, if a predetermined time shorter than 24 hours has elapsed, the control unit 23 will perform the circulation operation again.

[0120] From time T4 onward, the system repeatedly switches between the first and second states, causing the discharge and stopping of stored water. Then, at time T5, if the accumulated value Ad exceeds the threshold Th while stored water is being discharged from the discharge unit 14, the system switches to the third state. In the third state, regardless of whether or not an approach signal As is input, the state of the branching unit 17 is switched from a flow-allowed state to a flow-restricted state. Also, in the third state, the control unit 23 stops the operation of the pump 16 and the ultraviolet LED, regardless of whether or not an approach signal As is input. Simultaneously with the switch to the third state (at time T5), the control unit 23 lights up the notification unit 21.

[0121] In the third state, the control unit 23 restricts water discharge from the water discharge unit 14 regardless of the proximity signal As. After time T5, if the user realizes that no stored water is discharged from the water discharge unit 14 even when approaching the water discharge system 300, they check whether the notification unit 21 inside the cabinet C is lit through a maintenance window (not shown) provided in the cabinet C. If the user realizes that the notification unit 21 is lit, they clean the water storage tank 11 and store fresh tap water as stored water, replace the filter 12 with a new one, and reset the accumulated value Ad accumulated in the measurement unit 20 (for example, to 0). This allows the user to resume using the water discharge system 300.

[0122] [Regarding control of the circulating operation] The user can set the time to start the circulating operation to a desired time (a predetermined timing) by operating the control unit 24. In other words, the control unit 23 executes the circulating operation at the reference time set by the user. If the user does not set a time to start the circulating operation, the time to start the circulating operation is set to a pre-set initial time. The initial time is a time within the period when the user does not wash their hands (for example, midnight).

[0123] The control unit 23 starts the circulation operation when the current time reaches the reference time set by the user. In other words, the control unit 23 performs the circulation operation once every 24 hours. The time (predetermined time) during which bacteria are expected to begin to multiply in the stored water in the water storage tank 11 is approximately 40 hours. Therefore, the control unit 23 performs the circulation operation in a 24-hour cycle, which is the time until the expected time (40 hours) for bacteria to begin to multiply has elapsed.

[0124] As shown in Figure 8, in step S1, if the control unit 23 determines that the current time is the reference time set by the user (Yes in step S1), it proceeds to step S2 and executes a cyclic operation. In step S1, if the control unit 23 determines that the current time is not the reference time set by the user (No in step S1), it terminates the process shown in Figure 8. Then, the control unit 23 executes the process shown in Figure 8 again. In the process shown in Figure 8, after the control unit 23 starts the cyclic operation at the reference time set by the user (a predetermined timing), it prohibits the execution of the next cyclic operation until a specific time (24 hours) has elapsed from the time the execution of the cyclic operation ends.

[0125] [About the cleaning mode] The user can operate the control unit 23 to execute the cleaning mode by operating the control unit 24. The cleaning mode is a mode in which, while keeping the pump 16 in a driven state, the branching section 17 is switched between a flow-allowed state and a flow-restricted state at predetermined intervals, and stored water containing cleaning components is alternately flowed to both the supply passage 15 and the circulation passage 18. The number of times the branching section 17 is switched between the flow-allowed state and the flow-restricted state in the cleaning mode can be arbitrarily set by operating the control unit 24.

[0126] Specifically, first, the user adds a cleaning agent containing cleaning components to the stored water in the water storage tank 11. Then, the user sets the cleaning mode by operating the control unit 24. As shown in Figure 9, the control unit 23 determines in step S11 whether or not the cleaning mode has been set. In step S11, if the control unit 23 determines that the cleaning mode has been set (Yes in step S11), it proceeds to step S12. In step S12, the control unit 23 executes a cleaning mode in which the stored water containing cleaning components is alternately flowed through both the supply path 15 and the circulation path 18. In step S11, if the control unit 23 determines that the cleaning mode has not been set (No in step S11), it terminates the process shown in Figure 9. Then, the control unit 23 executes the process shown in Figure 9 again. In the cleaning mode, after the branching section 17 has been switched between a flow-allowing state and a flow-restricting state a specified number of times, the user cleans the water storage tank 11 and stores fresh tap water in the water storage tank 11. The user then places the water storage tank 11, which now contains the tap water, into the cabinet C. The user then deactivates the cleaning mode setting by operating the control unit 24.

[0127] As described above, the discharge system 300 of Embodiment 4 comprises a water storage tank 11 for storing stored water, a water treatment means 40 for treating the stored water, a supply passage 15 for supplying stored water from the water storage tank 11 via the water treatment means 40 to a discharge section 14 that discharges the stored water that has passed through the water treatment means 40, a pump 16 for sending stored water from the water storage tank 11 to the supply passage 15, and a circulation passage 18 connected to the water storage tank 11 upstream of the discharge section 14 in the supply passage 15. With this configuration, the discharge system 300 is expected to have the effect of suppressing bacterial growth by making the stored water less likely to stagnate by flowing the stored water through the circulation passage 18.

[0128] The water discharge system 300 includes a control unit 23 that controls the flow of stored water, and the control unit 23 performs a circulation operation at a predetermined timing to circulate the stored water in the water storage tank 11 through the circulation channel 18. With this configuration, the water discharge system 300 can maintain the stored water in a clean state by passing it through the reforming means 40 (filter 12) at a predetermined timing.

[0129] The control unit 23 performs a circulation operation from the time the water discharge from the water discharge unit 14 is stopped until a predetermined time has elapsed. With this configuration, the water discharge system 300 can reliably maintain the stored water in a clean state.

[0130] The predetermined time is the time it is assumed that bacteria will begin to proliferate in the stored water. With this configuration, the water discharge system 300 is expected to have an effect of efficiently suppressing bacterial growth.

[0131] The control unit 23 performs a circulation operation at a time set by the user. With this configuration, the water discharge system 300 is easy to use because it can circulate the stored water according to the user's lifestyle.

[0132] The control unit 23 can change the flow rate of the stored water flowing through the circulation channel 18 per unit time during circulation operation. With this configuration, for example, reducing the flow rate per unit time of the discharge system 300 can be expected to reduce the operating noise of the pump 16. Increasing the flow rate can be expected to complete the circulation of the stored water in a shorter period of time. In other words, the discharge system 300 can set the driving force of the pump 16 according to the user's wishes.

[0133] The control unit 23 prohibits the execution of the circulation operation until 24 hours (a specific time) have elapsed from the time the circulation operation is completed. With this configuration, the water discharge system 300 can avoid performing the circulation operation unnecessarily. This extends the lifespan of the filter 12.

[0134] The control unit 23 has a cleaning mode that alternately flows stored water containing cleaning components through both the supply passage 15 and the circulation passage 18. With this configuration, the water discharge system 300 can keep the paths through which the stored water flows clean.

[0135] The handwashing sink 4 comprises a water discharge system 300 and a sink 31 that receives water discharged from the water discharge section 14. With this configuration, the handwashing sink 4 is expected to have the effect of suppressing the growth of bacteria in the stored water.

[0136] <Embodiment 5> Embodiment 5, which embodies the present disclosure, will be described with reference to Figure 10. The configuration of Embodiment 5 is the same as that of Embodiment 4 shown in Figure 7, except that the control of the cyclic operation differs from that of Embodiment 4. Components similar to those in Embodiment 4 are denoted by the same reference numerals and their descriptions are omitted.

[0137] [Regarding control of the circulating operation] The user can set a reference time, which is the start time of the day, by operating the control unit 24. If the user does not set a reference time, the reference time will be set to a pre-set initial time. The initial time is a time within the period when the probability of the user washing their hands is low (for example, midnight).

[0138] The memory 23B of the control unit 23 is equipped with a "discharged" flag that indicates the first time water has been dispensed from the water dispenser 14 after the current time has elapsed from the reference time set by the user. The "discharged" flag is set to 1 when the first time water is dispensed from the water dispenser 14 after the current time has elapsed from the reference time set by the user. The "discharged" flag is set to 0 from the time the current time has elapsed until the first time water is dispensed from the water dispenser 14. The "discharged" flag is set to 0 when the current time has elapsed from the reference time set by the user.

[0139] The control unit 23 stops the water discharge from the water discharge unit 14 for the first time during a day, until 24 hours have passed from the reference time (predetermined time) set by the user, and then continuously performs a circulation operation. Here, "a day" is not limited to 24 hours from midnight to midnight, but also includes 24 hours based on the reference time set by the user. Based on the reference time set by the user, the control unit 23 first discharges water from the water discharge unit 14, and then continues the circulation operation by switching the branching unit 17 from a flow-allowed state to a flow-restricted state while keeping the pump 16 running. At the timing when the branching unit 17 is switched from a flow-allowed state to a flow-restricted state, the control unit 23 changes the force of the pump 16 to the force set by the user using the operation unit 24.

[0140] Next, we will describe a specific example of a control system that stops the water discharge from the water discharge unit 14 for the first time during a day, up to 24 hours after a predetermined time set by the user, and then continuously performs a circulation operation.

[0141] As shown in Figure 10, in step S21, the control unit 23 determines whether the current time has reached the reference time set by the user. If the control unit 23 determines in step S21 that the current time has reached the reference time set by the user (Yes in step S21), it proceeds to step S22, sets the water discharged flag to 0, and terminates the process shown in Figure 10. After that, the control unit 23 executes the process shown in Figure 10 again.

[0142] In step S21, if the control unit 23 determines that the current time is not the reference time set by the user (No in step S21), it proceeds to step S23. In step S23, the control unit 23 determines whether the approach signal As has switched from being input to not being input (whether the approach signal As has fallen from Hi to Lo). The determination in step S23 is equivalent to determining whether or not to terminate the water discharge from the water discharge unit 14.

[0143] In step S23, if the control unit 23 determines that the approach signal As has fallen from Hi to Lo (meaning that water discharge from the water discharge unit 14 has ended) (Yes in step S23), it proceeds to step S24 to determine whether the completed water discharge flag is 0 or not. In step S24, the control unit 23 determines whether the water discharge operation from the water discharge unit 14 has not been performed even once since the current time exceeded the reference time set by the user.

[0144] In step S24, if the control unit 23 determines that the discharged flag is 0 (Yes in step S24), it proceeds to step S25 and continues the circulation operation in conjunction with the discharge from the discharge unit 14. At this time, the control unit 23 continues to drive the pump 16 and switches the state of the branching unit 17 from a flow-allowed state to a flow-restricted state. Then, proceeding to step S26, the control unit 23 sets the discharged flag to 1 and terminates the process shown in Figure 10. After that, the control unit 23 executes the process shown in Figure 10 again.

[0145] In step S23, if the control unit 23 determines that the approach signal As has not fallen from Hi to Lo (i.e., the approach signal As has not changed from Lo, has not changed from Hi, or has risen from Lo to Hi) (No in step S23), it terminates the process shown in Figure 10. After that, the control unit 23 executes the process shown in Figure 10 again.

[0146] In step S24, if the control unit 23 determines that the "water discharged" flag is not 0 (meaning that the water discharge operation from the water discharge unit 14 has been performed for the first time since the reference time), it terminates the process shown in Figure 10. After that, the control unit 23 executes the process shown in Figure 10 again.

[0147] The control unit 23 stops the water discharge from the water discharge unit 14 for the first time during the day, up to 24 hours after a predetermined time, and then continuously performs a circulation operation. With this configuration, the water discharge system 300 can make the operating noise of the pump 16 less noticeable when the stored water is discharged into the circulation channel 18, compared to when the stored water is discharged into the circulation channel 18 alone, and can also maintain the stored water in a clean state.

[0148] <Embodiment 6> Embodiment 6, which embodies the present disclosure, will be described with reference to Figure 11. The configuration of Embodiment 6 is the same as that of Embodiment 4 shown in Figure 7, but the control of the cyclic operation differs from that of Embodiments 4 and 5. Components similar to those in Embodiment 4 are denoted by the same reference numerals and their descriptions are omitted.

[0149] [Regarding the control of the circulation operation] The control unit 23 performs the circulation operation from the time after the discharge of water from the discharge unit 14 is stopped until the time elapsed that is expected to be necessary for bacteria to begin to proliferate in the stored water. Specifically, the control unit 23 performs the circulation operation from immediately after the discharge of water from the discharge unit 14 until the time elapsed that is expected to be necessary for bacteria to begin to proliferate in the stored water (for example, 40 hours). At this time, the pump 16 is driven with the force set by the user using the control unit 24.

[0150] Next, we will describe a specific example of a control system that performs a circulation operation if water is not discharged from the discharge unit 14 between the time it is assumed that bacteria will begin to proliferate in the stored water after the water discharge from the discharge unit 14 has stopped.

[0151] As shown in Figure 11, in step S31, the control unit 23 determines whether the state has switched from one in which the approach signal As is input to one in which it is not input (i.e., whether the approach signal As has fallen from Hi to Lo).

[0152] In step S31, if the control unit 23 determines that the proximity signal As has fallen from Hi to Lo (to terminate water discharge from the water discharge unit 14) (Yes in step S31), it proceeds to step S32 and begins measuring the time (for example, 40 hours) during which bacteria are expected to begin to proliferate in the stored water. In step S32, the control unit 23 uses its timer function to measure 40 hours. If the control unit 23 determines that the time (for example, 40 hours) during which bacteria are expected to begin to proliferate in the stored water has not elapsed (No in step S32), it repeats the determination in step S32.

[0153] In step S32, if the control unit 23 determines that the time (e.g., 40 hours) during which bacteria are expected to begin to proliferate in the stored water has elapsed (Yes in step S32), it proceeds to step S33, executes the circulation operation, and terminates the process shown in Figure 11. After that, the control unit 23 executes the process shown in Figure 11 again.

[0154] The control unit 23 performs a circulation operation if no water is discharged from the discharge unit 14 between the time it is assumed that bacteria will begin to proliferate in the stored water (for example, 40 hours) after the water discharge from the discharge unit 14 has been stopped. With this configuration, the water discharge system 300 can protect the modification means 40 by minimizing the circulation operation as much as possible, and suppress the generation of operating noise of the pump 16 when it is not in use. The time it is assumed that bacteria will begin to proliferate in the stored water is not limited to 40 hours.

[0155] <Embodiment 7> A handwashing sink 5 equipped with a water discharge system 500 according to Embodiment 7, which embodies the present disclosure, will be described with reference to Figures 12 and 13. The handwashing sink 5 according to Embodiment 7 differs from Embodiments 4, 5, and 6 in the configuration of the second filter 112B, the configuration of the branching section 117, the configuration of the circulation flow path 118, and the control of the circulation operation. Components similar to those in Embodiment 4 are denoted by the same reference numerals and their descriptions are omitted.

[0156] The handwashing sink 5 comprises a water discharge system 500 and a sink 31. As shown in Figure 12, the water discharge system 500 comprises a water storage tank 11, a supply passage 15, a pump 16, a water discharge section 14, a water treatment means 400, a branching section 117, a circulation passage 118, a measuring section 20, a notification section 21, a detection section 19, a control section 23, and an operation section 24. The water treatment means 400 comprises a filter 112 and an ultraviolet sterilization means 13.

[0157] The filter 112 comprises a first filter 12A and a second filter 112B. The second filter 112B houses a known activated carbon filter and a known hollow fiber filter in a single case.

[0158] The branch section 117 includes a first branch section 117A and a second branch section 117B. The first branch section 117A and the second branch section 117B are known three-way valves. The first branch section 117A and the second branch section 117B are controlled by the control unit 23. The first branch section 117A is located upstream of the second filter 112B and downstream of the pump 16 in the supply path 15. The second branch section 117B is located upstream of the discharge section 14 and downstream of the second filter 112B in the supply path 15.

[0159] The circulation channel 118 has a first circulation channel 118A and a second circulation channel 118B. The first circulation channel 118A extends from the first branch 117A and connects to the middle of the inflow channel 30B. The first circulation channel 118A connects to the water storage tank 11 via the inflow channel 30B. In other words, the first circulation channel 118A connects to the water storage tank 11 upstream of the second filter 112B and downstream of the first filter 12A of the supply channel 15. The second circulation channel 118B extends from the second branch 117B and connects to the middle of the inflow channel 30B. The second circulation channel 118B connects to the water storage tank 11 via the inflow channel 30B. In other words, the second circulation channel 118B connects to the water storage tank 11 downstream of the second filter 112B of the supply channel 15.

[0160] The second filter 112B collects dust and other impurities that have passed through the first filter 12A (and were not collected by the first filter 12A). In other words, the second filter 112B collects smaller particles of dirt than the first filter 12A.

[0161] [Regarding control of the circulating operation] The user can set a reference time, which is the start time of the day, by operating the control unit 24. If the user does not set a reference time, the reference time will be set to a pre-set initial time. The initial time is a time within the period when the probability of the user washing their hands is low (for example, midnight).

[0162] The memory 23B of the control unit 23 is equipped with a "discharged" flag that indicates the first time water has been dispensed from the water dispenser 14 after the current time has elapsed from the reference time set by the user. The "discharged" flag is set to 1 when the first time water is dispensed from the water dispenser 14 after the current time has elapsed from the reference time set by the user. The "discharged" flag is set to 0 from the time the current time has elapsed until the first time water is dispensed from the water dispenser 14. The "discharged" flag is set to 0 when the current time has elapsed from the reference time set by the user.

[0163] The control unit 23 stops the first water discharge from the water discharge unit 14 during the day, until 24 hours have elapsed from the reference time (predetermined time) set by the user, and then continuously performs the first circulation operation. Here, "a day" is not limited to the 24 hours from midnight to midnight, but also includes the 24 hours based on the reference time set by the user. The first circulation operation is a circulation operation. The first circulation operation is the operation of switching the first branching unit 117A to a flow-allowing state and the second branching unit 117B to a flow-restricting state, driving the pump 16 to send stored water from the water storage tank 11 to the supply path 15, and circulating it back to the water storage tank 11 from the second circulation path 118B. In the first circulation operation, the control unit 23 passes approximately four times (20 L) the amount of stored water (5 L) stored in the water storage tank 11 through the filter 112 (first filter 12A and second filter 112B). The control unit 23 changes the force of the pump 16 to the force set by the user via the operation unit 24 at the timing of executing the first circulation operation.

[0164] The control unit 23 immediately performs the second circulation operation after stopping the water discharge from the water discharge unit 14 for the second time or later in a day, until the current time is 24 hours after the reference time (predetermined time) set by the user. The second circulation operation is a circulation operation. The second circulation operation is an operation in which the pump 16 is driven with the first branching unit 117A and the second branching unit 117B switched to a flow restriction state, sending stored water from the water storage tank 11 to the supply line 15, and circulating it back to the water storage tank 11 from the first circulation line 118A. In the second circulation operation, the control unit 23 allows approximately four times the amount of stored water (5L) stored in the water storage tank 11 (20L) to pass only through the first filter 12A. At the timing of executing the second circulation operation, the control unit 23 changes the force of the pump 16 to the force set by the user using the control unit 24.

[0165] Next, a specific example of the control performed by the control unit 23 to execute the first and second cyclic operations will be described.

[0166] As shown in Figure 13, in step S41, the control unit 23 determines whether the current time has reached the reference time set by the user. If the control unit 23 determines in step S41 that the current time has reached the reference time set by the user (Yes in step S41), it proceeds to step S42, sets the water discharged flag to 0, and terminates the process shown in Figure 13. After that, the control unit 23 executes the process shown in Figure 13 again.

[0167] In step S41, if the control unit 23 determines that the current time is not the reference time set by the user (No in step S41), it proceeds to step S43. In step S43, the control unit 23 determines whether the proximity signal As has fallen from Hi to Lo. The determination in step S43 is equivalent to determining whether or not to terminate the water discharge from the water discharge unit 14.

[0168] In step S43, if the control unit 23 determines that the approach signal As has fallen from Hi to Lo (meaning that water discharge from the water discharge unit 14 has ended) (Yes in step S43), it proceeds to step S44 to determine whether the water discharged flag is 0 or not. In step S44, the control unit 23 determines whether the water discharge operation from the water discharge unit 14 has not been performed even once since the current time exceeded the reference time set by the user.

[0169] In step S44, if the control unit 23 determines that the discharged flag is 0 (Yes in step S44), it proceeds to step S45 and executes the first circulation operation in conjunction with the discharge from the discharge unit 14. At this time, while continuing to drive the pump 16, the control unit 23 maintains the first branch 117A in a flow-allowed state and switches the second branch 117B from a flow-allowed state to a flow-restricted state to execute the first circulation operation. Then, proceeding to step S46, the control unit 23 sets the discharged flag to 1 and terminates the process shown in Figure 13. After that, the control unit 23 executes the process shown in Figure 13 again.

[0170] In step S43, if the control unit 23 determines that the approach signal As has not fallen from Hi to Lo (i.e., the approach signal As has not changed from Lo, has not changed from Hi, or has risen from Lo to Hi) (No in step S43), it terminates the process shown in Figure 13. After that, the control unit 23 executes the process shown in Figure 13 again.

[0171] In step S44, if the control unit 23 determines that the discharged flag is not 0 (meaning that the water discharge operation from the discharge unit 14 has been performed for the first time since the reference time), it proceeds to step S47 and executes the second circulation operation immediately following the water discharge from the discharge unit 14. At this time, while continuing to drive the pump 16, the control unit 23 switches the first branching unit 117A and the second branching unit 117B from a flow-allowed state to a flow-restricted state to execute the second circulation operation and complete the process shown in Figure 13. After that, the control unit 23 executes the process shown in Figure 13 again.

[0172] The control unit 23 performs a continuous circulation operation (first circulation operation and second circulation operation) after stopping the discharge of water from the discharge unit 14. With this configuration, the discharge system 500 can make the operating noise of the pump 16 when the stored water is discharged into the circulation channel 118 less noticeable compared to when the stored water is discharged into the circulation channel 118 by itself.

[0173] The modification means 400 includes a first filter 12A for collecting dirt and a second filter 112B for collecting dirt smaller than that of the first filter 12A. The circulation channel 118 includes a first circulation channel 118A connected to the water storage tank 11 upstream of the second filter 112B and downstream of the first filter 12A in the supply channel 15, and a second circulation channel 118B connected to the water storage tank 11 downstream of the second filter 112B in the supply channel 15. With this configuration, the water discharge system 500 can suppress the amount of stored water that flows to the second filter 112B compared to the first filter 12A by selecting either the first circulation channel 118A or the second circulation channel 118B as the channel through which the stored water flows. For example, if the second filter 112B is more expensive or has a shorter lifespan than the first filter 12A, it is possible to extend the lifespan of the second filter 112B and reduce the frequency of replacement of the second filter 112B.

[0174] This disclosure is not limited to the embodiments described above and in the drawings, and the technical scope of this disclosure also includes, for example, the following embodiments.

[0175] Since bacterial growth can be suppressed by performing the circulation operation at time intervals shorter than the time it is assumed that bacteria will begin to multiply (40 hours), the frequency of the circulation operation is not limited to every 24 hours; any interval shorter than 40 hours is acceptable, whether shorter or longer than 24 hours.

[0176] Unlike Embodiment 4 described above, a generation unit may be provided in the water storage tank to generate hypochlorous acid water by electrolyzing the stored water. In this case, without adding any chemicals to the water storage tank, the generation of hypochlorous acid water by the generation unit and the operation of switching the branching unit between a flow-allowed state and a flow-restricted state can be performed simultaneously by setting the cleaning mode, thereby cleaning the part of the water discharge system through which the stored water flows.

[0177] The amount of stored water circulated in a single circulation cycle should be equal to or greater than the amount of stored water that can be stored in the storage tank.

[0178] A commercially available faucet may be used for the water outlet.

[0179] The time it takes for bacteria to begin to proliferate in stored water is not limited to 40 hours, as it can be influenced by factors such as the amount of water stored in the storage tank, the quality of the tap water used for storage, air temperature, water temperature, and the materials of the supply and circulation channels.

[0180] Unlike Embodiment 4 described above, in the cleaning mode, stored water may be flowed simultaneously through the supply channel and the circulation channel. In this case, it is preferable that the branching section has a configuration that allows it to switch to a fully permissible state, in addition to a flow-permissible state and a flow-restricted state, which allows the flow of stored water between the supply channel and the circulation channel, and also allows the flow of stored water from the water storage tank to the discharge section.

[0181] Unlike the above embodiment, the amount of water stored in the storage tank may be more or less than 5 liters.

[0182] Unlike the above embodiment, an ultraviolet lamp may be used as the ultraviolet sterilization means.

[0183] Unlike the above embodiment, a bowl may be used instead of a sink.

[0184] 1, 2, 3... Washing system, 10, 100, 200... Water discharge system, 11... Water storage tank, 12... Filter, 13... Ultraviolet sterilization means, 14... Water discharge section, 15... Supply path, 16... Pump, 17, 117... Branching section, 18... Circulation path, 19... Detection section, 20... Measurement section, 21... Notification section, 22... Circulation path, Th... Threshold

[0185] 4, 5... Hand wash basin, 300, 500... Water discharge system, 11... Water storage tank, 12... Filter, 12A... First filter, 14... Water discharge section, 15... Supply path, 16... Pump, 17, 117... Branch section, 18, 118... Circulation path, 23... Control unit, 31... Sink, 112B... Second filter, 118A... First circulation path, 118B... Second circulation path, 40, 400... Modification means

Claims

1. A water discharge system comprising: a water storage tank for storing stored water; a reforming means for reforming the stored water; a supply path for supplying the stored water from the water storage tank, via the reforming means, to a discharge section for discharging the stored water that has passed through the reforming means; a pump for sending the stored water from the water storage tank to the supply path; and a circulation path connected to the water storage tank upstream of the discharge section in the supply path.

2. The water discharge system according to claim 1, wherein the modifying means includes a filter for removing at least one of bacteria and impurities from the stored water, and an ultraviolet sterilization means for sterilizing the stored water by irradiating it with ultraviolet light.

3. The water discharge system according to claim 2, wherein the stored water circulates through at least the water storage tank, the pump, the supply channel, the filter, a branching section located upstream of the water discharge section in the supply channel, and the circulation channel.

4. The water discharge system according to claim 2, wherein the stored water is constantly circulated through at least the water storage tank, the pump, the supply channel, the filter, the branching section located upstream of the water discharge section in the supply channel, and the circulation channel.

5. The water discharge system according to any one of claims 3 and 4, wherein the ultraviolet sterilization means is provided between the branching portion and the water discharge portion in the supply path.

6. The water discharge system according to either claim 3 or 4, wherein the ultraviolet sterilization means is provided at a location upstream of the branching portion in the supply path.

7. A water discharge system according to any one of claims 2 to 6, comprising a detection unit for detecting an object, wherein the ultraviolet sterilization means is driven when the detection unit detects the object, and stops driving when the detection unit no longer detects the object, or when a predetermined time has elapsed since the detection unit stopped detecting the object.

8. The water discharge system according to claim 7, which directly or indirectly references any one of claims 3 to 6, wherein when the detection unit detects the object, the branching section switches to a flow-permitting state that allows the flow of the stored water from the water storage tank to the water discharge section.

9. The water discharge system according to any one of claims 7 and 8, wherein the pump is driven when the detection unit detects the object.

10. The water discharge system according to any one of claims 1 to 9, further comprising a circulation path provided separately from the circulation channel for circulating the stored water stored in the water storage tank.

11. A water discharge system according to any one of claims 2 to 9, comprising: a measuring unit for measuring the cumulative flow rate of the stored water that has passed through the filter; and a notification unit for notifying that the cumulative flow rate has exceeded a threshold.

12. The water discharge system according to any one of claims 2 to 9, wherein when a detection unit for detecting an object located away from the water discharge unit detects the object, the system discharges stagnant water remaining in the supply path located upstream of the ultraviolet sterilization means from the water discharge unit.

13. The water discharge system according to claim 1, comprising a control unit for controlling the flow of the stored water, wherein the control unit performs a circulation operation to circulate the stored water in the water storage tank through the circulation channel at a predetermined timing.

14. The water discharge system according to claim 13, wherein the control unit performs the circulation operation between the time the water discharge from the water discharge unit is stopped and a predetermined time has elapsed.

15. The water discharge system according to claim 14, wherein the predetermined time is the time it is assumed that bacteria will begin to proliferate in the stored water.

16. The water discharge system according to claim 13, wherein the control unit performs the circulation operation at a time set by the user.

17. The water discharge system according to claim 13, wherein the control unit continues to perform the circulation operation after stopping the discharge of water from the water discharge unit.

18. The water discharge system according to claim 13, wherein the control unit stops the water discharge from the water discharge unit for the first time during a day, up to 24 hours after a predetermined time, and then continues to perform the circulation operation.

19. The water discharge system according to claim 13, wherein the control unit prohibits the execution of the circulation operation until a specific time has elapsed from the time the execution of the circulation operation is completed.

20. The water discharge system according to claim 13, wherein if water is not discharged from the water discharge unit between the time when water discharge from the water discharge unit is stopped and the time when it is assumed that bacteria will begin to proliferate in the stored water has elapsed, the control unit executes the circulation operation.

21. The water discharge system according to claim 13, wherein the control unit is capable of changing the flow rate of the stored water flowing through the circulation channel per unit time during the circulation operation.

22. The water discharge system according to claim 13, wherein the control unit has a cleaning mode that flows the stored water containing the cleaning component into both the supply passage and the circulation passage.

23. The water discharge system according to claim 1, wherein the modifying means comprises a first filter for collecting dirt and a second filter for collecting dirt smaller than that of the first filter, and the circulation channel comprises a first circulation channel connected to the water storage tank upstream of the second filter in the supply channel and downstream of the first filter, and a second circulation channel connected to the water storage tank downstream of the second filter in the supply channel.

24. A washbasin system comprising: a water discharge system according to any one of claims 1 to 23; and a bowl for receiving the stored water discharged from the water discharge section.

25. A handwashing basin comprising: a water discharge system according to any one of claims 1 to 23; and a sink that receives water discharged from the water discharge unit.

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