Sanitary Cleaning Device

Abstract

To provide a sanitary washing device in which earth fault current generated when earth fault occurs in a heat exchanger can be more surely interrupted even when the sanitary washing device is connected to an outlet with a connection portion reversed.SOLUTION: The sanitary washing device is provided, comprising: a connection portion having a first power source terminal and a second power source terminal; a heat exchanger having a heater; a spout nozzle spouting washing water; a temperature fuse and an electric current fuse placed on a power source path between one end of the heater and a first power source terminal; a switching element placed on a power source path between the other end of the heater and the second power source terminal; a control unit that controls the AC power supply to the heater; and a rectifier that rectifies electric current in such a manner that the electric current flows from one end to the other in the heater.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] SUMMARY OF THE INVENTION Aspects of the present invention generally relate to sanitary washing devices. [Background technology]

[0002] Sanitary washing devices that wash the private parts of the human body by spraying wash water are known. The sanitary washing devices have a heat exchanger that heats the wash water, and can spray warm water onto the private parts of the human body.

[0003] In such a sanitary washing device, if the heat exchanger breaks down due to a lightning strike or other cause, a ground fault may occur, causing current to flow from the hot-side path to the ground. When a ground fault occurs, the ground fault current may overheat the heat exchanger, causing high-temperature water to be discharged, or causing electric shock to personnel. Therefore, a safety device such as a thermal fuse or a current fuse is provided on the hot-side path so that the ground fault current can be immediately interrupted in the event of a ground fault.

[0004] However, if the hot and cold terminals of the sanitary washing device's connector (power plug) are reversed when the device is plugged into an outlet, and insulation breakdown occurs in the heat exchanger, ground-fault current will not flow through the thermal fuse or current fuse installed in the hot-side path, but will instead flow through the cold-side path. Therefore, if a ground-fault current flows through the cold-side path, control is performed to interrupt the ground-fault current, for example, by turning off a switching element installed in the cold-side path. However, if the switching element fails, it may not be possible to interrupt the ground-fault current flowing through the cold-side path. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Utility Model Application Publication No. 7-38281 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention was made based on the recognition of such problems, and aims to provide a sanitary cleaning device that can more reliably cut off ground fault current in the event of a ground fault in the heat exchanger, even if the connection part is connected to an outlet in an inverted state. [Means for solving the problem]

[0007] A first invention provides a water heater having a first power terminal and a second power terminal, a connection part electrically connected to an AC power supply via the first power terminal and the second power terminal, a ground electrode for grounding water flowing inside, and a heater part having a heater electrically insulated from the water flowing inside, one end of the heater being electrically connected to the first power terminal and the other end of the heater being electrically connected to the second power terminal, thereby heating cleaning water supplied from a water supply source using the heater based on AC power supplied to the heater from the power supply via the connection part, a spray nozzle which sprays cleaning water supplied through the heat exchanger, and a spray nozzle which is provided on a power supply path between one end of the heater and the first power terminal, and which when the temperature of the heat exchanger reaches a predetermined temperature or higher, a temperature fuse that opens the power supply path between one end of the heater and the first power supply terminal; a current fuse that is provided on the power supply path between the one end of the heater and the first power supply terminal and that opens the power supply path between the one end of the heater and the first power supply terminal when a current equal to or greater than a rated current flows; a switching element that is provided on the power supply path between the other end of the heater and the second power supply terminal and that switches between a state in which AC power is supplied to the heater and a state in which the supply of AC power to the heater is stopped; a control unit that controls the supply of AC power to the heater by controlling switching of the switching element; and a rectification unit that rectifies current so that it flows from the one end to the other end of the heater.

[0008] In this sanitary washing device, the rectifier can fix the direction of the current so that it flows from one end of the heater to the other. This allows the current fuse and thermal fuse to interrupt a ground fault current even when the first and second power terminals of the connection part are not reversed when the device is connected to an outlet, or when the first and second power terminals of the connection part are reversed when the device is connected to an outlet. In other words, even when the connection part is connected to an outlet in the reversed position, the ground fault current can be more reliably interrupted in the event of a ground fault in the heat exchanger. This improves user safety.

[0009] The second invention is a sanitary washing device characterized in that, in the first invention, it further comprises a temperature detection unit capable of detecting the temperature of the washing water heated by the heater unit, and the control unit executes a prohibition mode that prohibits the washing water from being sprayed from the spray nozzle when the temperature change during heating of the washing water detected by the temperature detection unit differs from a predetermined set temperature change.

[0010] According to this sanitary washing device, if the temperature change during heating of the wash water detected by the temperature detection unit differs from a preset temperature change, a prohibition mode is executed to prohibit the spraying of wash water from the spray nozzle, thereby preventing the user from getting an electric shock in the event of a ground fault and preventing high-temperature wash water from being sprayed from the spray nozzle in the event of a ground fault, thereby improving the safety of the user.

[0011] The third invention is a sanitary washing device according to the first or second invention, further comprising a temperature detection unit capable of detecting the temperature of the washing water heated by the heater unit, and an electromagnetic valve that controls the supply of washing water to the spray nozzle, and the control unit is characterized in that when the temperature trend of the washing water when heated detected by the temperature detection unit differs from a predetermined set temperature trend, the control unit executes a prohibition mode that prohibits the supply of water to the spray nozzle using the electromagnetic valve.

[0012] According to this sanitary washing device, if the temperature change during heating of the wash water detected by the temperature detection unit differs from the preset temperature change, the solenoid valve will activate a prohibition mode that prohibits water supply to the spray nozzle, thereby more reliably preventing high-temperature wash water from being sprayed from the spray nozzle in the event of a ground fault, thereby improving user safety.

[0013] The fourth invention is a sanitary washing device characterized in that, in any one of the first to third inventions, it is provided with a temperature detection unit capable of detecting the temperature of the washing water heated by the heater unit, and the control unit causes the switching element to stop supplying the AC power to the heater when the temperature of the washing water detected by the temperature detection unit is higher than a predetermined set temperature.

[0014] According to this sanitary washing device, if the temperature of the wash water detected by the temperature detection unit is higher than a preset temperature, the switching element stops the supply of AC power to the heater, thereby stopping the heating of the wash water when the wash water has been heated to a high temperature, thereby improving safety for the user.

[0015] A fifth invention is a sanitary washing device according to the second or third invention, characterized in that the control unit determines whether the temperature trend differs from the set temperature trend before starting to supply water to the spray nozzle.

[0016] With this sanitary washing device, by determining whether the temperature change of the washing water when heated differs from the set temperature change before starting to supply water to the spray nozzle, it is possible to more reliably prevent high-temperature washing water from being sprayed from the spray nozzle in the event of a ground fault, thereby improving the safety of the user.

[0017] A sixth invention is a sanitary washing device according to the second or third invention, characterized in that the control unit, while the prohibition mode is being executed, re-determines whether the temperature trend differs from the set temperature trend, and stops execution of the prohibition mode if the temperature trend does not differ from the set temperature trend.

[0018] According to this sanitary washing device, while the prohibition mode is being executed, it is determined again whether the temperature change when the washing water is heated differs from the set temperature change, and if the temperature change does not differ from the set temperature change, the execution of the prohibition mode is stopped, thereby canceling the prohibition mode when an erroneous determination of a malfunction occurs due to, for example, disturbance noise, etc. This improves usability.

[0019] A seventh invention is the sanitary washing device according to any one of the first to sixth inventions, characterized in that the rectification section performs full-wave rectification.

[0020] In this sanitary washing device, the rectifier performs full-wave rectification, which improves the heating efficiency in the heat exchanger compared to when the rectifier performs half-wave rectification, thereby improving usability. [Effects of the Invention]

[0021] According to an aspect of the present invention, a sanitary washing device is provided that can more reliably cut off ground fault current in the event of a ground fault in the heat exchanger, even if the connection part is connected to an outlet in an inverted state. [Brief explanation of the drawings]

[0022] [Figure 1] 1 is a block diagram showing the configuration of a main part of a sanitary washing device according to an embodiment. [Figure 2] FIG. 2 is a block diagram showing a part of the sanitary washing device according to the embodiment. [Figure 3] 3(a) and 3(b) are explanatory diagrams showing the flow straightening section of the sanitary washing device according to the embodiment. [Figure 4]4(a) and 4(b) are graphs showing an example of temperature transition during heating of cleaning water. [Figure 5] 4 is a flowchart showing an example of the operation of the sanitary washing device according to the embodiment. [Figure 6] 4 is a flowchart showing an example of the operation of the sanitary washing device according to the embodiment. [Figure 7] FIG. 10 is a block diagram showing a part of a reference sanitary washing device. DETAILED DESCRIPTION OF THE INVENTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, like components are designated by like reference numerals and detailed descriptions thereof will be omitted where appropriate. FIG. 1 is a block diagram showing the configuration of the main parts of a sanitary washing device according to an embodiment. As shown in Fig. 1, the sanitary washing device 10 includes a heat exchanger 20, a jet nozzle 30, and a control unit 40. Note that Fig. 1 also shows the main components of the water channel system and the main components of the electrical system of the sanitary washing device 10.

[0024] The heat exchanger 20 has a first heater 21 and a second heater 22. The resistance value of the second heater 22 is, for example, higher than the resistance value of the first heater 21. The heat exchanger 20 heats the flushing water supplied from the water supply source WS using the first heater 21 and the second heater 22. However, the number of heaters provided in the heat exchanger 20 is not limited to two, and may be one, or three or more.

[0025] The jet nozzle 30 has a jet outlet 32 ​​provided at its tip. The jet nozzle 30 jets out the cleaning water supplied via the heat exchanger 20 from the jet outlet 32 ​​to wash the body (e.g., the buttocks) of a user sitting on a toilet seat (not shown), for example.

[0026] For example, as shown in Fig. 1, a sanitary washing device 10 according to this embodiment has a flow path 12 that guides water supplied from a water supply source WS, such as a tap or a water tank, to a spray outlet 32 ​​of a spray nozzle 30. A solenoid valve 14 is provided upstream of the flow path 12. The solenoid valve 14 is an electromagnetic valve that can be opened and closed, and controls the supply of water based on commands from a control unit 40. In other words, the solenoid valve 14 switches between supplying water from the water supply source WS to the spray nozzle 30 and stopping the water supply.

[0027] A heat exchanger 20 is provided downstream of the solenoid valve 14. The heat exchanger 20 heats water supplied from the water supply source WS using a first heater 21 and a second heater 22, raising the temperature of the water to, for example, a specified temperature. The heat exchanger 20 converts the water supplied from the water supply source WS into hot water at a set temperature.

[0028] The heat exchanger 20 of this embodiment is, for example, an instantaneous heating type (instantaneous type) heat exchanger that uses a cylindrical ceramic heater or the like. The first heater 21 and the second heater 22 are, for example, heater patterns provided on the ceramic heater. The instantaneous type heat exchanger 20 heats water by flowing it inside, without storing the water in a tank or the like. Note that the heat exchanger 20 may also be a hot water storage type heat exchanger that heats water stored in a tank.

[0029] Provided downstream of the heat exchanger 20 are a flow rate switching valve 33 that adjusts the flow rate, and a flow path switching valve 34 that opens and closes the water supply to the jet nozzle 30 and the nozzle cleaning chamber 36 and switches the water supply destination. The flow rate switching valve 33 adjusts the flow rate of water flowing to the jet nozzle 30. The flow path switching valve 34 can switch the water supply destination (the connection destination of the flow path) to either the jet nozzle 30 or the nozzle cleaning chamber 36. The flow rate switching valve 33 and the flow path switching valve 34 may be provided as a single unit.

[0030] A jet nozzle 30 is provided downstream of the flow rate switching valve 33 and the flow path switching valve 34. The jet nozzle 30 receives a driving force from a nozzle motor 38 and can advance into the bowl of the toilet or retreat into the casing. In other words, the nozzle motor 38 can move the jet nozzle 30 forward and backward based on commands from the control unit 40.

[0031] The nozzle cleaning chamber 36 can sterilize or clean the outer peripheral surface (body) of the spray nozzle 30 by spraying sterilizing water or water from a water discharge section (not shown) provided inside the nozzle cleaning chamber 36. Alternatively, the nozzle cleaning chamber 36 can sterilize or clean the spray outlet 32 ​​of the spray nozzle 30 when it is stored.

[0032] For example, by operating the operation unit 50, the user can start or stop the discharge of wash water from the jet nozzle 30. For example, by operating the operation unit 50, the user can set the temperature of the wash water heated in the heat exchanger 20. The operation unit 50 is, for example, a remote control that is installed on the wall of the toilet room. The operation unit 50 may also be, for example, an operation panel that is integrally provided on the casing of the sanitary washing device 10.

[0033] The control unit 40 receives power from the power supply PS via an input circuit 41 and a power supply circuit 42, and controls the operations of the solenoid valve 14, the heat exchanger 20, the flow rate switching valve 33, the flow path switching valve 34, and the nozzle motor 38 based on signals from the operation unit 50 etc. For example, the control unit 40 controls the power supplied from the power supply PS to the first heater 21 and the second heater 22 of the heat exchanger 20.

[0034] The power supply PS is, for example, an AC power supply. The power supply PS is, for example, a commercial power supply of AC 100V (effective value). The input circuit 41 is a circuit that absorbs electrical noise and external surge voltages that enter from the power supply PS. The input circuit 41 also serves the purpose of preventing noise generated by the equipment itself from being output to the power supply PS to prevent malfunctions in peripheral equipment. The input circuit 41 is composed of a capacitor, a coil, a varistor for absorbing surges, and the like. The first heater 21 and the second heater 22 of the heat exchanger 20 are connected to the power supply PS via the input circuit 41. AC power is supplied to the first heater 21 and the second heater 22 via the input circuit 41. Meanwhile, DC power is supplied to the control unit 40 via the input circuit 41 and a power supply circuit 42. The power supply circuit 42 is provided on the path between the input circuit 41 and the control unit 40, converts the AC power supplied from the power supply PS into DC power, and supplies the converted DC power to the control unit 40.

[0035] FIG. 2 is a block diagram showing a part of the sanitary washing device according to the embodiment. As shown in FIG. 2, the sanitary washing device 10 includes a connection unit 60, a rectification unit 45, a first switching element 71, a second switching element 72, a current fuse 74, and a thermal fuse 76.

[0036] The heat exchanger 20 includes a heater section 112 having a first heater 21 and a second heater 22, a case 114, and a ground electrode 134. The first heater 21 and the second heater 22 are electrically insulated from the water flowing inside the heat exchanger 20. The ground electrode 134 grounds the water flowing inside the heat exchanger 20.

[0037] The connection unit 60 has a first power supply terminal 61 and a second power supply terminal 62. The first power supply terminal 61 is, for example, a power supply terminal electrically connected to the power line (non-grounded side) of the AC power supply PS. The second power supply terminal 62 is, for example, a power supply terminal electrically connected to the neutral line (grounded side) of the AC power supply PS. The first power supply terminal 61 is, for example, a live side power supply terminal (L-side power supply terminal), and the second power supply terminal 62 is, for example, a neutral side power supply terminal (N-side power supply terminal). However, the first power supply terminal 61 may be, for example, the grounded side, and the second power supply terminal 62 may be, for example, the non-grounded side, as opposed to the above.

[0038] The connection unit 60 is, for example, an outlet plug. The first power terminal 61 is, for example, one terminal of the outlet plug, and the second power terminal 62 is, for example, the other terminal of the outlet plug. However, the connection unit 60 is not limited to an outlet plug, and may be, for example, a pair of wires directly connected to a switchboard or the like.

[0039] The heat exchanger 20 electrically connects one end of the first heater 21 and one end of the second heater 22 to a first power supply terminal 61, and electrically connects the other end of the first heater 21 and the other end of the second heater 22 to a second power supply terminal 62, thereby heating the cleaning water supplied from the water supply source WS by at least one of the first heater 21 and the second heater 22 based on the AC power supplied to the first heater 21 and the second heater 22 from the power supply PS via the connection part 60.

[0040] In this example, an input circuit 41 is provided between the heat exchanger 20 and the connection unit 60. The input circuit 41 outputs, for example, AC power supplied from the power supply PS directly to the heat exchanger 20. However, the input circuit 41 may also convert the AC power supplied from the power supply PS into another AC power and output the converted AC power to the heat exchanger 20. In this way, the AC power supplied from the power supply PS to the heat exchanger 20 may be the AC power of the power supply PS directly, or may be AC ​​power that has been converted by the input circuit 41 or the like. The AC power supplied to the heat exchanger 20 may be any AC power based on the AC power of the power supply PS.

[0041] A rectifier 45 is provided between the heat exchanger 20 and the input circuit 41. In this example, the rectifier 45 is provided on the power supply path between one end of the first heater 21 and one end of the second heater 22 and the first power supply terminal 61, and on the power supply path between the other end of the first heater 21 and the other end of the second heater 22 and the second power supply terminal 62.

[0042] The rectification unit 45 rectifies the current so that it flows from one end to the other end in the first heater 21 and the second heater 22. In other words, it fixes the direction of the current (voltage polarity) in the first heater 21 and the second heater 22. The rectification unit 45 will be described later.

[0043] The first switching element 71 is provided on the power supply path between the other end of the first heater 21 and the second power supply terminal 62, and switches between a state in which AC power is supplied to the first heater 21 and a state in which the supply of AC power to the first heater 21 is stopped.

[0044] The second switching element 72 is provided on the power supply path between the other end of the second heater 22 and the second power supply terminal 62, and switches between a state in which AC power is supplied to the second heater 22 and a state in which the supply of AC power to the second heater 22 is stopped.

[0045] The first switching element 71 is provided, for example, between the other end of the first heater 21 and one of the AC output terminals of the input circuit 41. Similarly, the second switching element 72 is provided, for example, between the other end of the second heater 22 and one of the AC output terminals of the input circuit 41. However, the arrangement of the first switching element 71 is not limited to this and may be at any position on the power supply path between the other end of the first heater 21 and the second power supply terminal 62. The arrangement of the second switching element 72 is not limited to this and may be at any position on the power supply path between the other end of the second heater 22 and the second power supply terminal 62.

[0046] The first switching element 71 and the second switching element 72 have, for example, a pair of main terminals and a control terminal, and switch on / off the current flowing between the pair of main terminals in response to a signal input to the control terminal. The first switching element 71 and the second switching element 72 are, for example, semiconductor switches. The first switching element 71 and the second switching element 72 may be, for example, a thyristor or a triac. The first switching element 71 and the second switching element 72 may be, for example, any element that can control the on / off of a current and that can cause a current to flow in at least one direction. The first switching element 71 and the second switching element 72 may be, for example, a combination of multiple semiconductor switches.

[0047] The first heater 21 and the second heater 22 generate heat by, for example, passing a current between a pair of terminals. The first heater 21 and the second heater 22 are, for example, resistors.

[0048] The control unit 40 controls the supply of AC power to the first heater 21 by controlling the switching of the first switching element 71, and controls the supply of AC power to the second heater 22 by controlling the switching of the second switching element 72. The control unit 40 controls the switching of each of the first switching element 71 and the second switching element 72 by, for example, being electrically connected to the control terminals of the first switching element 71 and the second switching element 72.

[0049] The current fuse 74 is provided on the power supply path between one end of the first heater 21 and one end of the second heater 22 and the first power supply terminal 61. When a current greater than the rated current flows, the current fuse 74 cuts off the power supply to the first heater 21 and the second heater 22 by opening the power supply path between the connection portion 60 and the first heater 21 and the power supply path between the connection portion 60 and the second heater 22. In this way, the current fuse 74 prevents a current greater than the rated current from flowing into the heat exchanger 20. It is preferable that the current fuse 74 be provided on the non-grounded power supply terminal of the first power supply terminal 61 or the second power supply terminal 62.

[0050] Current fuse 74 opens the power supply path by melting when, for example, a current equal to or greater than the rated current flows. Current fuse 74 may be a self-recovery fuse that opens the power supply path by opening its contacts when a current equal to or greater than the rated current flows, and reconnects the power supply path by closing its contacts when the rated current falls below the rated current.

[0051] The thermal fuse 76 is provided on a power supply path between one end of the first heater 21 and one end of the second heater 22 and the first power supply terminal 61. One end of the first heater 21 and one end of the second heater 22 are electrically connected to the first power supply terminal 61 via the thermal fuse 76.

[0052] When the temperature of the heat exchanger 20 reaches or exceeds a predetermined temperature, the thermal fuse 76 opens the power supply path between one end of the first heater 21 and one end of the second heater 22 and the first power terminal 61, thereby cutting off the power supply to the first heater 21 and the second heater 22. In this way, the thermal fuse 76 prevents the heat exchanger 20 from generating heat above the predetermined temperature. The thermal fuse 76 prevents, for example, the heat exchanger 20 from running dry.

[0053] For example, when the temperature of the heat exchanger 20 reaches or exceeds a predetermined temperature, the thermal fuse 76 melts to open the power supply path between one end of the first heater 21 and one end of the second heater 22 and the first power supply terminal 61. The thermal fuse 76 may be a self-recovery fuse that opens the power supply path by opening a contact when the temperature of the heat exchanger 20 reaches or exceeds a predetermined temperature, and closes the contact when the temperature of the heat exchanger 20 falls below the predetermined temperature to reconnect the power supply path.

[0054] In this example, the sanitary washing device 10 further includes a temperature detection unit 84. The temperature detection unit 84 is capable of detecting the temperature of the washing water heated by the heater unit 112. The temperature detection unit 84 is, for example, a thermistor. The temperature detection unit 84 is electrically connected to the control unit 40 and outputs the detection result to the control unit 40.

[0055] The rectification unit 45 will be described with reference to FIGS. 3(a) and 3(b). 3(a) and 3(b) are explanatory diagrams showing the flow straightening section of the sanitary washing device according to the embodiment. 3(a), the rectifier 45 is, for example, a diode bridge, and is provided on a power supply path between the heat exchanger 20 (the first heater 21 and the second heater 22) and the connection unit 60 (the first power supply terminal 61 and the second power supply terminal 62).

[0056] As shown in FIG. 3(b), when the rectifier 45 performs full-wave rectification, the rectifier 45 fixes the direction of current flow by converting the negative voltage component of the AC input voltage into a positive voltage.

[0057] As shown by the solid arrows in Fig. 3(a), the current flowing from the first power supply terminal 61 side flows through diode D4, heat exchanger 20, and diode D2 in this order, before flowing to the second power supply terminal 62. On the other hand, as shown by the dashed arrows in Fig. 3(a), the current flowing from the second power supply terminal 62 side flows through diode D3, heat exchanger 20, and diode D1 in this order, before flowing to the first power supply terminal 61. In this way, the rectifier 45 fixes the direction of the current in the first heater 21 and the second heater 22 by rectification. In other words, the rectifier 45 prevents a ground-fault current from flowing in the cold-side path.

[0058] In this example, the rectifier 45 performs full-wave rectification, but the rectifier 45 may also perform half-wave rectification. In this case, the rectifier 45 is, for example, a diode. When the rectifier 45 performs half-wave rectification, the rectifier 45 fixes the direction of current flow by eliminating the negative voltage component of the input voltage. However, from the viewpoint of heating efficiency in the heat exchanger 20, it is preferable that the rectifier 45 perform full-wave rectification.

[0059] 4(a) and 4(b) are graphs showing an example of temperature transition during heating of cleaning water. In Figure 4(a), the solid line shows an example of the temperature transition of the wash water when heated when the rectification unit 45 is not malfunctioning. In Figure 4(b), the solid line shows an example of the temperature transition of the wash water when heated when the rectification unit 45 is malfunctioning, and the two-dot chain line shows an example of the temperature transition of the wash water when heated when the rectification unit 45 is not malfunctioning. The temperature transition of the wash water when heated is detected, for example, by the temperature detection unit 84.

[0060] As shown in Figure 4(a), if rectification unit 45 is not malfunctioning, when power is started to be supplied to the heater at time t1, the temperature of the wash water rises and reaches a predetermined temperature at time t2. Once the temperature of the wash water reaches the predetermined temperature, control unit 40 performs heat retention control to maintain the temperature of the wash water at the predetermined temperature, for example, by controlling the power supply to the heater every half wave. Control unit 40 stores, for example, the temperature transition during heating of the wash water when rectification unit 45 is not malfunctioning, as a preset set temperature transition.

[0061] On the other hand, as shown in Figure 4(b), if the rectifier 45 is faulty, for example, no current is applied during the half-wave portion indicated by the dashed line. Therefore, when current is applied to the heater at time t1, the temperature of the wash water rises, but even at time t2, the temperature of the wash water has not reached the predetermined temperature. Furthermore, when the temperature of the wash water reaches the predetermined temperature at time t3, the control unit 40 performs heat retention control to maintain the temperature of the wash water at the predetermined temperature, for example by controlling the current application to the heater every half-wave, but is unable to maintain the temperature of the wash water at the predetermined temperature.

[0062] In this way, the temperature transition of the wash water when it is heated in a case where the rectification unit 45 is malfunctioning differs from the temperature transition of the wash water when it is heated in a case where the rectification unit 45 is not malfunctioning. More specifically, for example, the gradient (rate of increase) of the temperature transition of the wash water when it is heated in a case where the rectification unit 45 is malfunctioning is smaller than the gradient (rate of increase) of the temperature transition of the wash water when it is heated in a case where the rectification unit 45 is not malfunctioning. Also, for example, the temperature of the wash water a predetermined time after the start of heating in a case where the rectification unit 45 is malfunctioning is lower than the temperature of the wash water a predetermined time after the start of heating in a case where the rectification unit 45 is not malfunctioning. Also, for example, the temperature of the wash water a predetermined time after it reaches a predetermined temperature in a case where the rectification unit 45 is malfunctioning is lower than the temperature of the wash water a predetermined time after it reaches a predetermined temperature in a case where the rectification unit 45 is not malfunctioning.

[0063] The control unit 40 can determine that the temperature transition of the wash water when heated is abnormal, for example, when the temperature transition of the wash water when heated detected by the temperature detection unit 84 differs from a preset set temperature transition (i.e., the temperature transition of the wash water when heated when the rectification unit 45 is not malfunctioning). The control unit 40 can determine that the rectification unit 45 is malfunctioning, for example, when the temperature transition of the wash water when heated detected by the temperature detection unit 84 differs from a preset set temperature transition (i.e., the temperature transition of the wash water when heated when the rectification unit 45 is not malfunctioning). When the control unit 40 determines that the temperature transition of the wash water when heated is abnormal (when it determines that the rectification unit 45 is malfunctioning), for example, the control unit 40 executes a prohibition mode, which will be described later.

[0064] FIG. 5 is a flowchart showing an example of the operation of the sanitary washing device according to the embodiment. 5, the control unit 40 determines whether or not a command signal to start water discharge from the jet nozzle 30 has been received (step S101). The control unit 40 repeats step S101 until a command signal to start water discharge from the jet nozzle 30 has been received (step S101: No).

[0065] When a command signal to start water discharge from the jet nozzle 30 is received (step S101: Yes), the control unit 40 determines whether the temperature transition during heating of the wash water is normal or not (step S102).

[0066] If it is determined that the temperature transition during heating of the cleaning water is normal (step S102: Yes), the control unit 40 starts supplying water to the jet nozzle 30 (step S103).

[0067] If it is determined that the temperature transition during heating of the cleaning water is abnormal (step S102: No), the control unit 40 starts execution of the prohibition mode (step S104). In the prohibition mode, the control unit 40 prohibits, for example, the spraying of cleaning water from the spray nozzle 30. The control unit 40 prohibits the spraying of cleaning water from the spray nozzle 30, for example, by prohibiting the spray nozzle 30 from advancing. Furthermore, in the prohibition mode, the control unit 40 may prohibit the supply of water to the spray nozzle 30, for example, by closing the solenoid valve 14.

[0068] When the prohibition mode is started, the control unit 40 re-determines whether the temperature transition of the washing water when heated is normal (step S105). If the re-determination determines that the temperature transition of the washing water when heated is abnormal (step S105: No), the control unit 40 continues the prohibition mode.

[0069] If the control unit 40 determines in the re-determination that the temperature transition during heating of the wash water is normal (step S105: Yes), the control unit 40 stops the execution of the prohibition mode (step S106). In other words, if the control unit 40 determines in the re-determination that the temperature transition during heating of the wash water is normal, it cancels the prohibition mode.

[0070] FIG. 6 is a flowchart showing an example of the operation of the sanitary washing device according to the embodiment. 6, the control unit 40 determines whether the temperature of the washing water detected by the temperature detection unit 84 is higher than a preset temperature (step S201). The preset temperature is, for example, 40°C.

[0071] If the temperature of the cleaning water detected by the temperature detection unit 84 is equal to or lower than the preset temperature (step S201: Yes), the control unit 40 maintains the supply of AC power to the first heater 21 and the second heater 22 (step S202).

[0072] If the temperature of the washing water detected by the temperature detection unit 84 is higher than the preset temperature (step S201: No), the control unit 40 stops the supply of AC power to the first heater 21 and the second heater 22 (step S203). The control unit 40 stops the supply of AC power to the first heater 21 and the second heater 22 by turning off the first switching element 71 and the second switching element 72.

[0073] When the supply of AC power to first heater 21 and second heater 22 is stopped, control unit 40 re-determines whether the temperature of the wash water detected by temperature detection unit 84 is higher than the preset temperature (step S204). If the re-determination determines that the temperature of the wash water detected by temperature detection unit 84 is higher than the preset temperature (step S204: No), control unit 40 continues the state in which the supply of AC power to first heater 21 and second heater 22 is stopped.

[0074] If it is determined in the re-determination that the temperature of the wash water detected by the temperature detection unit 84 is equal to or lower than the preset temperature (step S204: Yes), the control unit 40 resumes the supply of AC power to the first heater 21 and the second heater 22 (step S205). In other words, if it is determined in the re-determination that the temperature of the wash water detected by the temperature detection unit 84 is equal to or lower than the preset temperature, the control unit 40 releases the state in which the supply of AC power to the first heater 21 and the second heater 22 has been stopped.

[0075] FIG. 7 is a block diagram showing a part of a reference sanitary washing device. FIG. 7 shows a schematic representation of a part of a reference sanitary washing device in which the rectification unit 45 is omitted and only a current fuse 74 and a thermal fuse 76 are provided.

[0076] As shown in Figure 7, in the configuration of the reference sanitary cleaning device, when a breakdown occurs between the water flowing inside and the first heater 21 or the second heater 22 and the temperature fuse 76 melts due to abnormal heat generation, depending on the location of the breakdown, current may flow from the first heater 21 or the second heater 22 to the ground side via the internal water.

[0077] 7 illustrates a case where breakdown occurs between the water flowing inside and the second heater 22 at one end of the second heater 22 near the first power supply terminal 61. In this case, if the connection between the connection part 60 and the power supply PS is incorrect and the second power supply terminal 62 is connected to the power line side of the power supply PS, current will flow from the second power supply terminal 62 through the second switching element 72, the second heater 22, and from the breakdown part to the ground electrode 134 via the water inside the heat exchanger 20, as indicated by arrow A1 in FIG. 7. In this case, current will continue to flow to the second heater 22 even after the current fuse 74 and the thermal fuse 76 have blown, which may make it impossible to properly stop the heat generation of the second heater 22.

[0078] In contrast, in the sanitary washing device 10 according to this embodiment, the heat exchanger 20 has a ground electrode 134 that grounds the water flowing inside. This prevents current leaking from the first heater 21 and the second heater 22 into the water from traveling through the water and affecting the human body, even if dielectric breakdown occurs between the water flowing inside and the first heater 21 and the second heater 22. This improves safety against electric leakage from the first heater 21 and the second heater 22.

[0079] In the sanitary washing device 10, the rectifier 45 can fix the direction of current so that the current flows from one end to the other end of the heaters (first heater 21 and second heater 22). This allows the current fuse 74 and the thermal fuse 76 to interrupt a ground fault current even when the connector 60 is connected to an outlet with the first power supply terminal 61 and the second power supply terminal 62 not reversed, or when the connector 60 is connected to an outlet with the first power supply terminal 61 and the second power supply terminal 62 reversed. In other words, even when the connector 60 is connected to an outlet with the connector 60 reversed, the ground fault current can be more reliably interrupted in the event of a ground fault in the heat exchanger 20. This improves user safety.

[0080] Furthermore, by executing a prohibition mode that prohibits the spraying of wash water from the spray nozzle 30 when the temperature transition during heating of the wash water detected by the temperature detection unit 84 differs from a preset set temperature transition, it is possible to prevent the user from getting an electric shock in the event of a ground fault and also to prevent high-temperature wash water from being sprayed from the spray nozzle 30 in the event of a ground fault, thereby improving the safety of the user.

[0081] Furthermore, if the temperature transition of the wash water when heated, detected by the temperature detection unit 84, differs from the preset temperature transition, the prohibition mode is executed, which prohibits the supply of water to the jet nozzle 30 by the solenoid valve 14, thereby more reliably preventing high-temperature wash water from being jetted from the jet nozzle 30 in the event of a ground fault. This increases the safety of the user.

[0082] Furthermore, when the temperature of the wash water detected by the temperature detection unit 84 is higher than a preset temperature, the switching elements (first switching element 71 and second switching element 72) are set to a state in which the supply of AC power to the heaters (first heater 21 and second heater 22) is stopped, thereby making it possible to stop heating the wash water when the wash water has been heated to a high temperature. This increases the safety of the user.

[0083] Furthermore, by determining whether the temperature transition of the wash water when heated differs from the set temperature transition before starting to supply water to the spray nozzle 30, it is possible to more reliably prevent high-temperature wash water from being sprayed from the spray nozzle 30 in the event of a ground fault. This increases the safety of the user.

[0084] Furthermore, while the prohibition mode is being executed, it is determined again whether the temperature change during heating of the wash water differs from the set temperature change, and if the temperature change does not differ from the set temperature change, execution of the prohibition mode is stopped, so that the prohibition mode can be cancelled if an erroneous determination of a malfunction occurs due to, for example, disturbance noise, etc. This improves usability.

[0085] Furthermore, by performing full-wave rectification by the rectification unit 45, the heating efficiency in the heat exchanger 20 can be improved compared to when the rectification unit 45 performs half-wave rectification, thereby improving usability.

[0086] As described above, according to the embodiment, a sanitary cleaning device is provided that can more reliably cut off ground fault current in the event of a ground fault in the heat exchanger, even if the connection part is connected to the outlet in an inverted state.

[0087] The above describes the embodiments of the present invention. However, the present invention is not limited to these descriptions. Design modifications made by a person skilled in the art to the above-described embodiments are also included within the scope of the present invention as long as they incorporate the features of the present invention. For example, the shape, dimensions, materials, and arrangement of each element of a sanitary washing device are not limited to those illustrated and can be modified as appropriate. Furthermore, the elements of each of the above-described embodiments can be combined to the extent technically possible, and such combinations are also included within the scope of the present invention as long as they include the features of the present invention. [Explanation of symbols]

[0088] 10 Sanitary cleaning equipment 12 Flow path 14 Solenoid valve 20 Heat exchanger 21 First heater 22 Second heater 30 Spout Nozzle 32 spout 33 Flow switching valve 34 Flow path switching valve 36 Nozzle cleaning chamber 38 nozzle motor 40 Control Unit 41 Input circuit 42 Power supply circuit 45 Rectifier 50 Control section 60 Connection 61 1st power supply terminal 62 2nd power supply terminal 71 First switching element 72 second switching element 74 Current fuse 76 Thermal fuse 84 Temperature detection unit 112 Heater section 114 cases 134 Ground electrode PS power supply WS water source

Claims

1. a connection portion having a first power supply terminal and a second power supply terminal, the connection portion being electrically connected to an AC power supply via the first power supply terminal and the second power supply terminal; a heat exchanger having a ground electrode that grounds the water flowing therein and a heater section having a heater electrically insulated from the water flowing therein, wherein one end of the heater is electrically connected to the first power supply terminal and the other end of the heater is electrically connected to the second power supply terminal, thereby heating flush water supplied from a water supply source by the heater based on power supplied to the heater from the power supply via the connection section; a spray nozzle that sprays cleaning water supplied through the heat exchanger; a thermal fuse that is provided on a power supply path between one end of the heater and the first power supply terminal, and that opens the power supply path between one end of the heater and the first power supply terminal when the temperature of the heat exchanger reaches or exceeds a predetermined temperature; a current fuse that is provided on a power supply path between one end of the heater and the first power supply terminal, and that opens the power supply path between one end of the heater and the first power supply terminal when a current equal to or greater than a rated current flows; a switching element that is provided on a power supply path between the other end of the heater and the second power supply terminal and that switches between a state in which the power is supplied to the heater and a state in which the supply of the power to the heater is stopped; a control unit that controls the supply of power to the heater by controlling switching of the switching element; a rectification unit that fixes the voltage polarity of the power supplied from the power supply to the heater in one direction and rectifies the current so that the current flows from the one end to the other end of the heater; A sanitary washing device comprising:

2. Further, a temperature detection unit capable of detecting the temperature of the cleaning water heated by the heater unit is provided, The sanitary washing device described in claim 1, characterized in that the control unit executes a prohibition mode that prohibits the spraying of cleaning water from the spray nozzle when the temperature change of the cleaning water when heated detected by the temperature detection unit differs from a predetermined set temperature change.

3. The washing machine further includes a temperature detection unit capable of detecting the temperature of the washing water heated by the heater unit, and an electromagnetic valve for controlling the supply of washing water to the jet nozzle, The sanitary washing device described in claim 1 or 2, characterized in that the control unit executes a prohibition mode in which the solenoid valve prohibits water from being supplied to the spray nozzle when the temperature change of the washing water when heated detected by the temperature detection unit differs from a predetermined set temperature change.

4. a temperature detection unit capable of detecting the temperature of the cleaning water heated by the heater unit; A sanitary washing device described in any one of claims 1 to 3, characterized in that the control unit causes the switching element to stop supplying the power to the heater when the temperature of the washing water detected by the temperature detection unit is higher than a predetermined set temperature.

5. The sanitary washing device according to claim 2 or 3, wherein the control unit determines whether the temperature transition differs from the set temperature transition before starting to supply water to the jet nozzle.

6. The sanitary washing device described in claim 2 or 3, characterized in that the control unit re-determines whether the temperature trend differs from the set temperature trend while the prohibition mode is being executed, and stops execution of the prohibition mode if the temperature trend does not differ from the set temperature trend.

7. The sanitary washing device according to any one of claims 1 to 6, wherein the rectification unit performs full-wave rectification.

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