EP4141179A1

EP4141179A1 - Sanitary cleaning device

Info

Publication number: EP4141179A1
Application number: EP22191766.9A
Authority: EP
Inventors: Shonosuke SAWA; Ikko Hatta; Mizuki IDE; Ryohei Kaneko
Original assignee: Toto Ltd
Current assignee: Toto Ltd
Priority date: 2021-08-23
Filing date: 2022-08-23
Publication date: 2023-03-01
Also published as: CN115711479A; JP2023030624A

Abstract

Provided is a sanitary cleaning device capable of more appropriately stopping heat generation of a heater while enhancing safety against electric leakage from the heater even when dielectric breakdown occurs between water flowing inside and the heater in an instantaneous heat exchanger.Provided is a sanitary cleaning device including: a connecting portion including a first power supply terminal and a second power supply terminal; a heat exchanger including a ground electrode that grounds water flowing inside, and a heater unit including a heater electrically insulated from the water flowing inside; a jet nozzle that jets cleaning water; a switching element provided on a power supply path between the other end of the heater and the second power supply terminal; a control unit that controls supply of AC power to the heater by switching of the switching element; a first temperature fuse provided on a power supply path between one end of the heater and the first power supply terminal; and a second temperature fuse provided on the power supply path between the other end of the heater and the second power supply terminal.

Description

Technical Field

An aspect of the present invention relates generally to a sanitary cleaning device.

Background Art

A sanitary cleaning device that jets cleaning water to clean a private part of a human body is known. The sanitary cleaning device includes a heat exchanger that heats cleaning water, and is capable of jetting hot water to a private part of a human body.
As a heat exchanger used in a sanitary cleaning device, a so-called instantaneous heat exchanger that performs heating while flowing water inside without storing water in a tank or the like is known. The instantaneous heat exchanger includes a heater. The heater heats water flowing inside the heat exchanger. The sanitary cleaning device includes a temperature fuse. When abnormal heat is generated due to empty heating or the like, the temperature fuse suppresses abnormal heat generation by opening a power supply path according to a temperature and stopping energization to the heater of the heat exchanger.
The instantaneous heat exchanger electrically insulates the heater from the water flowing inside. In addition, in the instantaneous heat exchanger, it has been proposed to ground water flowing inside the heat exchanger. As a result, even if dielectric breakdown occurs between the water flowing inside and the heater, it is possible to suppress the influence of the current leakage from the heater to the water on the human body through the water.
That is, safety against electric leakage from the heater can be enhanced.
However, when the water flowing inside the heat exchanger is grounded in this manner, dielectric breakdown occurs between the water flowing inside and the heater, and when the temperature fuse opens the power supply path due to abnormal heat generation, a current may flow from the heater to the ground side via the water inside depending on the position where the dielectric breakdown occurs. In this case, the current continues to flow through the heater even after the temperature fuse opens the power supply path, and there is a possibility that the heat generation of the heater cannot be appropriately stopped.
For this reason, in the sanitary cleaning device, even when the dielectric breakdown occurs between the water flowing inside and the heater in the instantaneous heat exchanger, it is desirable to increase the safety against the electric leakage from the heater and to more appropriately stop the heat generation of the heater.

Citation List

Patent Literature

Patent Literature 1: JP 2018-31201 A

Summary of Invention

Technical Problem

The present invention has been made based on recognition of such a problem, and an object of the present invention is to provide a sanitary cleaning device capable of more appropriately stopping heat generation of a heater while enhancing safety against electric leakage from the heater even when dielectric breakdown occurs between water flowing inside and the heater in an instantaneous heat exchanger.

Solution to Problem

A first aspect of the invention is a sanitary cleaning device including: a connecting portion including a first power supply terminal and a second power supply terminal, the connecting portion being electrically connected to an AC power supply via the first power supply terminal and the second power supply terminal; a heat exchanger including a ground electrode that grounds water flowing inside, and a heater unit having a heater electrically insulated from the water flowing inside, in which 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, so that cleaning water supplied from a water supply source is heated by the heater based on AC power supplied from the power supply to the heater via the connecting portion; a jet nozzle that jets cleaning water supplied through the heat exchanger; 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 switches between a state in which the AC power is supplied to the heater and a state in which supply of the AC power to the heater is stopped; a control unit that controls switching of the switching element to control supply of the AC power to the heater; a first temperature fuse provided on a power supply path between one end of the heater and the first power supply terminal, the first temperature fuse opening the power supply path between the one end of the heater and the first power supply terminal when a temperature of the heat exchanger becomes equal to or higher than a predetermined temperature; and a second temperature fuse provided on the power supply path between the other end of the heater and the second power supply terminal, the second temperature fuse opening the power supply path between the other end of the heater and the second power supply terminal when a temperature of the heat exchanger becomes equal to or higher than a predetermined temperature.
According to the sanitary cleaning device, the heat exchanger includes the ground electrode that grounds water flowing inside. As a result, even if dielectric breakdown occurs between the water flowing inside and the heater, it is possible to suppress the influence of the current leakage from the heater to the water on the human body through the water, and to enhance the safety against the electric leakage from the heater. The sanitary cleaning device further includes the first temperature fuse provided on the power supply path between one end of the heater and the first power supply terminal, and the second temperature fuse provided on the power supply path between the other end of the heater and the second power supply terminal. As a result, when abnormal heat generation occurs due to dielectric breakdown between the water flowing inside and the heater, the power supply paths are opened by the first temperature fuse and the second temperature fuse, so that the heat generation of the heater can be appropriately stopped even if the dielectric breakdown occurs at any position. By opening the power supply paths at both ends of the heater, it is possible to suppress the current from continuing to flow through the heater even after the power supply paths are opened by the temperature fuses. Therefore, it is possible to provide a sanitary cleaning device capable of more appropriately stopping heat generation of a heater while enhancing safety against electric leakage from the heater even when dielectric breakdown occurs between water flowing inside and the heater in an instantaneous heat exchanger.
According to a second aspect of the present invention, in the sanitary cleaning device according to the first aspect, the heater unit is provided at a position between the first temperature fuse and the second temperature fuse.
According to this sanitary cleaning device, even if temperature unevenness occurs in the surface temperature of the heater unit, the abnormality of the high temperature can be easily detected, and the heat generation of the heater can be stopped quickly at the time of the abnormality.
According to a third aspect of the present invention, in the sanitary cleaning device according to the first or second aspect of the present invention, the first temperature fuse and the second temperature fuse are provided at positions different in height from the heater unit.
According to this sanitary cleaning device, even if temperature unevenness occurs in the surface temperature in the height direction of the heater unit, the abnormality of the high temperature can be easily detected, and the heat generation of the heater can be stopped quickly at the time of the abnormality.
According to a fourth aspect of the present invention, in the sanitary cleaning device according to the third aspect of the present invention, at least a part of the second temperature fuse is provided at a position point-symmetrical to at least a part of the first temperature fuse about a central axis of the heater unit.
According to this sanitary cleaning device, even if temperature unevenness occurs in the surface temperature of the heater unit, the abnormality of the high temperature can be detected more easily, and the heat generation of the heater can be stopped more quickly at the time of the abnormality.

Advantageous Effects of Invention

According to an aspect of the present invention, there is provided a sanitary cleaning device capable of more appropriately stopping heat generation of a heater while enhancing safety against electric leakage from the heater even when dielectric breakdown occurs between water flowing inside and the heater in an instantaneous heat exchanger.

Brief Description of Drawings

FIG. 1 is a block diagram showing a configuration of a main part of a sanitary cleaning device according to an embodiment;
FIG. 2 is a cross-sectional view schematically illustrating the heat exchanger according to the embodiment;
FIG. 3 is an enlarged cross-sectional view schematically illustrating a part of the heat exchanger according to the embodiment;
FIG. 4 is an enlarged cross-sectional view schematically illustrating a part of the heat exchanger according to the embodiment;
FIG. 5 is a circuit diagram showing a part of the sanitary cleaning device according to the embodiment;
FIG. 6 is a cross-sectional view schematically showing a part of the sanitary cleaning device according to the embodiment; and
FIG. 7 is a circuit diagram showing a part of a reference sanitary cleaning device.

Description of Embodiments

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals, and the detailed description thereof will be omitted as appropriate.
FIG. 1 is a block diagram showing a configuration of a main part of a sanitary cleaning device according to an embodiment.
As shown in FIG. 1, the sanitary cleaning device 10 includes a heat exchanger 20, a jet nozzle 30, and a control unit 40. In FIG. 1, a configuration of a main part of a water passage system and a configuration of a main part of an electric system of the sanitary cleaning device 10 are shown together.
The heat exchanger 20 includes a first heater 21 and a second heater 22. The resistance value of the second heater 22 is higher than the resistance value of the first heater 21, for example. The heat exchanger 20 heats cleaning water supplied from a water supply source WS by 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.
The jet nozzle 30 has a jet port 32 provided at the tip portion. The jet nozzle 30 jets the cleaning water supplied through the heat exchanger 20 from the jet port 32 to clean, for example, a human body (for example, "buttocks") of a user sitting on a toilet seat (not shown).
For example, as shown in FIG. 1, the sanitary cleaning device 10 according to the present embodiment has a flow path 12 for guiding water supplied from the water supply source WS such as a tap or a water storage tank to the jet port 32 of the jet nozzle 30. An electromagnetic valve 14 is provided on the upstream side of the flow path 12. The electromagnetic valve 14 is an openable and closable electromagnetic valve, and controls the supply of water based on a command from the control unit 40. That is, the electromagnetic valve 14 switches between supply of water supplied from the water supply source WS to the jet nozzle 30 and stop of water.
The heat exchanger 20 is provided downstream of the electromagnetic valve 14. The heat exchanger 20 heats the water supplied from the water supply source WS by the first heater 21 and the second heater 22 to raise the temperature of the water to, for example, a prescribed temperature. The heat exchanger 20 converts the water supplied from the water supply source WS into hot water having a set temperature.
The heat exchanger 20 of the present embodiment is, for example, an instantaneous heating (instantaneous) heat exchanger using a cylindrical ceramic heater or the like. The first heater 21 and the second heater 22 are, for example, heater patterns provided on ceramic heaters. The instantaneous heat exchanger 20 performs heating while flowing water inside without storing water in a tank or the like. A user can set the hot water temperature by operating an operation unit 50. The operation unit 50 is, for example, a remote controller installed on a wall of a toilet room or the like. The operation unit 50 may be, for example, an operation panel integrally provided on a casing of the sanitary cleaning device 10.
A flow rate switching valve 33 that adjusts a flow rate and a flow path switching valve 34 that opens and closes water supply to the jet nozzle 30 and the nozzle cleaning chamber 36 and switches a water supply destination are provided downstream of the heat exchanger 20. 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 a water supply destination (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 one unit.
The 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 the nozzle motor 38, and can advance into a bowl of a toilet bowl or retract into the casing. That is, the nozzle motor 38 can move the jet nozzle 30 forward and backward based on a command from the control unit 40.
The nozzle cleaning chamber 36 can sterilize or clean the outer peripheral surface (body) of the jet nozzle 30 by injecting sterilizing water or water from a water discharge unit (not shown) provided inside the nozzle cleaning chamber 36. Alternatively, the nozzle cleaning chamber 36 can sterilize or clean the portion of the jet port 32 of the accommodated jet nozzle 30.
The control unit 40 is supplied with power from a power supply PS via a power supply circuit 42, and controls the operations of the electromagnetic 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 a signal from the operation unit 50 or the like. For example, the control unit 40 controls power supplied from the power supply PS to the first heater 21 and the second heater 22 of the heat exchanger 20.
The power supply PS is, for example, an AC power supply. The power supply PS is, for example, an AC 100 V (effective value) commercial power supply. The power supply circuit 42 converts AC power supplied from the power supply PS into DC power, and supplies the converted DC power to the control unit 40. On the other hand, the power supply circuit 42 supplies AC power to the first heater 21 and the second heater 22 of the heat exchanger 20.
FIG. 2 is a cross-sectional view schematically illustrating the heat exchanger according to the embodiment.
As shown in FIG. 2, the heat exchanger 20 includes a heater unit 112, a case 114, a shaft core member 116, and a coil spring 118.
The heater unit 112 has a cylindrical shape having a hollow portion 112a. In other words, the heater unit 112 is a cylindrical heater. The first heater 21 and the second heater 22 of the heat exchanger 20 are provided in the heater unit 112. Note that the heater unit 112 does not need to be a perfect cylinder, and may have a portion where the thickness changes. The cross-sectional shape of the heater unit 112 does not need to be a perfect circle, and may partially have an elliptical portion, a polygonal portion, or the like. The heater unit 112 may have a substantially cylindrical outer shape.
The heater unit 112 is, for example, a cylindrical ceramic heater. The heater unit 112 includes, for example, an outer portion forming an outer peripheral surface 112b of the heater unit 112, an inner portion forming an inner peripheral surface 112c of the heater unit 112, and a heat generation unit provided between the inner portion and the outer portion. The inner portion and the outer portion are formed of ceramics. The heat generation unit has, for example, a film shape in which the first heater 21 and the second heater 22 (heater patterns) having a band shape and made of tungsten or the like are sandwiched between insulating films. As a result, in the heater unit 112, water in contact with the outer peripheral surface 112b and the inner peripheral surface 112c can be heated.
The inner portion and the outer portion formed of ceramics are insulators.
The outer peripheral surface 112b and the inner peripheral surface 112c have electrical insulation. As a result, the heat exchanger 20 electrically insulates the water flowing in contact with the outer peripheral surface 112b and the inner peripheral surface 112c from the first heater 21 and the second heater 22. The heater unit 112 includes the first heater 21 and the second heater 22 electrically insulated from water flowing inside. The inner portion and the outer portion have, for example, high electrical insulation and high thermal conductivity.
The case 114 covers the outer periphery of the heater unit 112. The case 114 includes, for example, a case body 120 and a lid portion 122. The case body 120 covers the outer periphery of the heater unit 112. The case body 120 has, for example, a cylindrical shape having a diameter larger than that of the heater unit 112.
The case body 120 has a hollow portion 120a that accommodates the heater unit 112. The heater unit 112 is disposed substantially coaxially in the hollow portion 120a of the cylindrical case body 120, for example.
However, the shape of the case body 120 may be any shape that can cover the outer periphery of the heater unit 112. For example, the case body 120 may have a rectangular parallelepiped shape having a columnar hollow portion 120a capable of accommodating the heater unit 112.
One end of the heater unit 112 is located inside one end of the case body 120. In other words, one end of the heater unit 112 is located in the hollow portion 120a. On the other hand, the other end of the heater unit 112 is located outside the other end of the case body 120. However, the other end of the heater unit 112 may be located inside the other end of the case body 120.
The lid portion 122 is provided at one end of the case body 120 on the side where the heater unit 112 does not protrude, and closes one end of the cylindrical case body 120. The lid portion 122 may be formed integrally with the case body 120, for example. The hollow portion 120a may have, for example, a bottomed hole shape with one end closed. The case 114 may be configured to accommodate the heater unit 112 by the hollow portion 120a having a bottomed hole shape.
The shaft core member 116 is provided in the hollow portion 112a of the heater unit 112. The shaft core member 116 is formed separately from the case 114 and is not fixed to the case 114.
The shaft core member 116 has, for example, a substantially columnar shape extending in the axial direction of the heater unit 112, and is disposed substantially coaxially in the hollow portion 112a of the cylindrical heater unit 112.
One end of the heater unit 112 and one end of the shaft core member 116 are disposed away from the case 114. More specifically, one end of the heater unit 112 and one end of the shaft core member 116 are disposed away from the lid portion 122 of the case 114. The space between one end of the heater unit 112 and one end of the shaft core member 116 and the lid portion 122 serves as a path for flowing water between the inside and the outside of the heater unit 112.
The coil spring 118 is provided between the shaft core member 116 and the inner peripheral surface 112c of the heater unit 112. The coil spring 118 is made of metal or resin, for example. The outer diameter of the coil spring 118 in the natural length state is slightly larger than the inner diameter of the inner peripheral surface 112c of the heater unit 112. The coil spring 118 is provided in the hollow portion 112a of the heater unit 112 in a state where the diameter is slightly reduced by twisting. As a result, the coil spring 118 abuts on the inner peripheral surface 112c of the heater unit 112, and is held in the hollow portion 112a of the heater unit 112 by its own elastic force to return the diameter.
FIG. 3 is an enlarged cross-sectional view schematically illustrating a part of the heat exchanger according to the embodiment.
As shown in FIGS. 2 and 3, the case body 120 of the case 114 forms an outer flow path 130 with the outer peripheral surface 112b of the heater unit 112. The case body 120 has a protruding portion 120b. The protruding portion 120b protrudes inward from the inner peripheral surface of the case body 120 and extends spirally along the axial direction of the case body 120.
The heat exchanger 20 further includes a coil spring 124. The coil spring 124 is provided between the case body 120 and the outer peripheral surface 112b of the heater unit 112. The coil spring 124 is made of metal or resin, for example. The inner diameter of the coil spring 124 in the natural length state is slightly smaller than the outer diameter of the outer peripheral surface 112b of the heater unit 112. The coil spring 124 is provided on the outer peripheral surface 112b of the heater unit 112 in a state where the diameter is slightly increased by twisting. As a result, the coil spring 124 abuts on the outer peripheral surface 112b of the heater unit 112, and is held on the outer peripheral surface 112b of the heater unit 112 by its own elastic force to return the diameter.
The inner diameter of the case body 120 at the tip portion of the protruding portion 120b of the case body 120 is slightly larger than the outer diameter of the outer peripheral surface 112b of the heater unit 112. Therefore, a slight gap is formed between the case body 120 and the heater unit 112.
A thickness (diameter) of the strand of the coil spring 124 is larger than a distance of a gap formed between the case body 120 and the heater unit 112. The pitch of the coil spring 124 is substantially the same as the pitch of the spiral protruding portion 120b. Accordingly, the coil spring 124 closes a gap between the case body 120 and the outer peripheral surface 112b of the heater unit 112.
The heater unit 112 is supported by the case body 120 (case 114), for example, and is disposed substantially coaxially in the hollow portion 120a of the cylindrical case body 120.
As a result, the spiral outer flow path 130 is formed by the protruding portion 120b of the case body 120 and the coil spring 124. As described above, by making the outer flow path 130 spiral, the heat exchange rate between the water flowing through the outer flow path 130 and the heater unit 112 can be increased. In addition, by forming the spiral outer flow path 130 using the coil spring 124, it is possible to suppress the influence of an assembly error, a dimensional error, and the like by the coil spring 124 and to easily form the spiral outer flow path 130.
FIG. 4 is an enlarged cross-sectional view schematically illustrating a part of the heat exchanger according to the embodiment.
As shown in FIGS. 2 and 4, the shaft core member 116 forms an inner flow path 132 with the inner peripheral surface 112c of the heater unit 112. The shaft core member 116 has a protruding portion 116a. The protruding portion 116a protrudes outward from the outer peripheral surface of the shaft core member 116 and extends spirally along the axial direction of the shaft core member 116.
The outer diameter of the shaft core member 116 at the tip portion of the protruding portion 116a of the shaft core member 116 is slightly smaller than the inner diameter of the inner peripheral surface 112c of the heater unit 112. Therefore, a slight gap is formed between the shaft core member 116 and the heater unit 112.
A thickness (diameter) of the strand of the coil spring 118 is larger than a distance of a gap formed between the shaft core member 116 and the heater unit 112. The pitch of the coil spring 118 is substantially the same as the pitch of the spiral protruding portion 116a. Accordingly, the coil spring 118 closes a gap between the shaft core member 116 and the inner peripheral surface 112c of the heater unit 112.
For example, the shaft core member 116 is supported by the heater unit 112 via the coil spring 118 without being directly supported by the heater unit 112 and the case body 120 (case 114), and is disposed substantially coaxially in the hollow portion 112a of the cylindrical heater unit 112 via the coil spring 118. That is, the shaft core member 116 is positioned by the coil spring 118 without being positioned by the case 114. In this manner, the gap between the shaft core member 116 and the inner peripheral surface 112c of the heater unit 112 is filled with the coil spring 118, and the shaft core member 116 is positioned with respect to the heater unit 112 by the coil spring 118.
As a result, the spiral inner flow path 132 is formed by the protruding portion 116a of the shaft core member 116 and the coil spring 118. As described above, by making the inner flow path 132 spiral, the heat exchange rate between the water flowing through the inner flow path 132 and the heater unit 112 can be increased. In addition, by forming the spiral inner flow path 132 using the coil spring 118, it is possible to suppress the influence of an assembly error, a dimensional error, and the like by the coil spring 118 and to easily form the spiral inner flow path 132.
As shown in FIG. 2, to the other end of the heater unit 112 protruding outward from the other end of the case body 120, a water passing member 140 for flowing water to the hollow portion 112a of the heater unit 112 is connected. The case body 120 is provided with a water passage port 120c for flowing water into the hollow portion 120a of the case body 120. The water passage port 120c is provided at the end portion of the case body 120 on the same side as the end portion of the heater unit 112 on the side to which the water passing member 140 is connected.
In the heat exchanger 20, for example, water is supplied from the water passing member 140 into the hollow portion 112a of the heater unit 112. The water supplied into the hollow portion 112a flows through the inner flow path 132 toward the end portion on the opposite side of the heater unit 112. At this time, the water flowing through the inner flow path 132 is heated by the heater unit 112 by coming into contact with the inner peripheral surface 12c of the heater unit 112. The water having flowed through the inner flow path 132 enters the outer flow path 130 through a space between the end portion of the heater unit 112 in the hollow portion 120a of the case body 120 and the lid portion 122, and flows through the outer flow path 130.
The water flowing through the outer flow path 130 flows toward the end portion on the opposite side of the heater unit 112 again. At this time, the water flowing through the outer flow path 130 is heated by the heater unit 112 by coming into contact with the outer peripheral surface 112b of the heater unit 112. The water having flowed through the outer flow path 130 is discharged to the outside of the case body 120 (heat exchanger 20) through the water passage port 120c.
As a result, the water supplied to the heat exchanger 20 via the water passing member 140 is heated by the heater unit 112 and replaced with hot water, and the hot water is discharged from the heat exchanger 20. Contrary to the above, water may be supplied from the water passage port 120c, and the generated hot water may be discharged to the water passing member 140.
A power supply terminal 112d for supplying power to the first heater 21 and the second heater 22 of the heater unit 112 is provided at the other end of the heater unit 112 protruding outward from the other end of the case body 120. In this manner, the power supply terminal 112d is provided at the end opposite to the end portion on the opposite side in contact with water. Accordingly, exposure with water of the power supply terminal 112d is suppressed.
As shown in FIG. 2, the heat exchanger 20 includes a ground electrode 134. The ground electrode 134 is provided at a position in contact with water flowing inside the heat exchanger 20 (case 114), and grounds the water flowing inside the heat exchanger 20.
The potential of the ground electrode 134 is set to a reference potential. In other words, the ground electrode 134 sets the potential of the water flowing inside the heat exchanger 20 to the reference potential. The reference potential is, for example, a potential of a neutral line of the AC power supply PS. The reference potential is, for example, a ground potential. The reference potential may be, for example, a potential of frame grounding. The ground electrode 134 is set to the reference potential by being connected to an external electrode via, for example, a wire led out to the outside of the case 114. However, the method of setting the potential of the ground electrode 134 is not limited to the above, and any method may be used.
In this manner, the heat exchanger 20 is provided with the ground electrode 134 and grounds the water flowing inside. As a result, even if dielectric breakdown occurs between the water flowing inside and the heater unit 112 (the first heater 21 and the second heater 22), the current leaking from the heater unit 112 to the water can flow to the ground electrode 134. Accordingly, it is possible to suppress the influence of the current leaking from the heater unit 112 to the water on the human body sitting on the toilet seat through the water. That is, safety against electric leakage from the heater unit 112 can be enhanced.
The ground electrode 134 is provided, for example, on the inner surface of the lid portion 122. As a result, the water flowing through the inner flow path 132 can be brought into contact with the ground electrode 134 while entering the outer flow path 130 through the space between the end portion of the heater unit 112 in the hollow portion 120a of the case body 120 and the lid portion 122. However, the arrangement of the ground electrode 134 is not limited to the above, and may be any position where the ground electrode 134 can be brought into contact with water flowing inside the heat exchanger 20.
FIG. 5 is a circuit diagram showing a part of the sanitary cleaning device according to the embodiment.
As shown in FIG. 5, the sanitary cleaning device 10 includes a connecting portion 60, a first switching element 71, a second switching element 72, a current fuse 74, a first temperature fuse 81, and a second temperature fuse 82.
The connecting portion 60 includes 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 a power supply line (non-ground side) of the AC power supply PS. The second power supply terminal 62 is, for example, a power supply terminal electrically connected to a neutral line (ground side) of the AC power supply PS. The first power supply terminal 61 is, for example, a live power supply terminal (L-side power supply terminal), and the second power supply terminal 62 is, for example, a neutral power supply terminal (N-side power supply terminal). However, contrary to the above, the first power supply terminal 61 may be on the ground side, and the second power supply terminal 62 may be on the non-ground side.
The connecting portion 60 is, for example, an outlet plug. The first power supply terminal 61 is, for example, one terminal of the outlet plug, and the second power supply terminal 62 is, for example, the other terminal of the outlet plug. However, the connecting portion 60 is not limited to the outlet plug, and may be, for example, a pair of wires directly connected to a power distribution board or the like.
In the heat exchanger 20, 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, and the other end of the first heater 21 and the other end of the second heater 22 are electrically connected to the second power supply terminal 62, so that cleaning water supplied from the water supply source WS is heated by at least one of the first heater 21 and the second heater 22 on the basis of AC power supplied from the power supply PS to the first heater 21 and the second heater 22 via the connecting portion 60.
In this example, the power supply circuit 42 is provided between the heat exchanger 20 and the connecting portion 60. The power supply circuit 42 outputs, for example, AC power supplied from the power supply PS to the heat exchanger 20 as it is. However, the power supply circuit 42 may convert the AC power supplied from the power supply PS into other AC power and output the converted AC power to the heat exchanger 20. As described above, the AC power supplied from the power supply PS to the heat exchanger 20 may be the AC power of the power supply PS as it is, or may be the AC power after power conversion is performed by the power supply circuit 42 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.
The first switching element 71 is provided on a power supply path between the other end of the first heater 21 and the second power supply terminal 62, and switches between a state of supplying AC power to the first heater 21 and a state of stopping the supply of AC power to the first heater 21.
The second switching element 72 is provided on a power supply path between the other end of the second heater 22 and the second power supply terminal 62, and switches between a state of supplying AC power to the second heater 22 and a state of stopping the supply of AC power to the second heater 22.
The first switching element 71 is provided, for example, between the other end of the first heater 21 and one AC output terminal of the power supply circuit 42. Similarly, the second switching element 72 is provided, for example, between the other end of the second heater 22 and one AC output terminal of the power supply circuit 42. However, the arrangement of the first switching element 71 is not limited to this, and may be 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 any position on the power supply path between the other end of the second heater 22 and the second power supply terminal 62.
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 of a current flowing between the pair of main terminals according to a signal input to the control terminal. For example, triacs are used as the first switching element 71 and the second switching element 72. The first switching element 71 and the second switching element 72 may be, for example, any element capable of controlling on/off of a current and allowing a current to flow bidirectionally. The first switching element 71 and the second switching element 72 may be, for example, mechanical relays or the like, or may be configured by combining a plurality of semiconductor switches or the like.
The first heater 21 and the second heater 22 generate heat by, for example, flowing a current between the pair of terminals. The first heater 21 and the second heater 22 are, for example, resistors.
The control unit 40 controls the switching of the first switching element 71 to control the supply of the AC power to the first heater 21, and controls the switching of the second switching element 72 to control the supply of the AC power to the second heater 22. For example, the control unit 40 is electrically connected to the control terminals of the first switching element 71 and the second switching element 72 to control switching of the first switching element 71 and the second switching element 72.
The current fuse 74 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. When a current equal to or higher than the rated current flows, the current fuse 74 interrupts power supply to the first heater 21 and the second heater 22 by opening a power supply path between the connecting portion 60 and the first heater 21 and a power supply path between the connecting portion 60 and the second heater 22. As a result, the current fuse 74 prevents a current equal to or higher than the rated current from flowing into the heat exchanger 20. The current fuse 74 is preferably provided at a power supply terminal on the non-ground side of the first power supply terminal 61 and the second power supply terminal 62.
The current fuse 74 opens the power supply path by fusing, for example, when a current equal to or higher than the rated current flows. The current fuse 74 may be, for example, a self-recovering fuse that opens the power supply path by opening a contact when a current equal to or higher than the rated current flows, and connects the power supply path again by closing the contact when the rated current becomes lower than the rated current.
The first temperature fuse 81 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. The second temperature fuse 82 is provided on a 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. 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 first temperature fuse 81. The other end of the first heater 21 and the other end of the second heater 22 are electrically connected to the second power supply terminal 62 via the second temperature fuse 82.
When the temperature of the heat exchanger 20 becomes equal to or higher than a predetermined temperature, the first temperature fuse 81 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 supply terminal 61, and cuts off power supply to the first heater 21 and the second heater 22. When the temperature of the heat exchanger 20 becomes equal to or higher than a predetermined temperature, the second temperature fuse 82 opens 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, and cuts off power supply to the first heater 21 and the second heater 22. Accordingly, the first temperature fuse 81 and the second temperature fuse 82 prevent the heat exchanger 20 from generating heat equal to or higher than a predetermined temperature. The first temperature fuse 81 and the second temperature fuse 82 suppress empty heating of the heat exchanger 20, for example.
For example, when the temperature of the heat exchanger 20 becomes equal to or higher than a predetermined temperature, the first temperature fuse 81 is fused 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. For example, the first temperature fuse 81 may be a self-recovering fuse that opens the power supply path by opening the contact when the temperature of the heat exchanger 20 becomes equal to or higher than a predetermined temperature, and connects the power supply path again by closing the contact when the temperature of the heat exchanger 20 becomes lower than the predetermined temperature. The same applies to the second temperature fuse 82.
The second temperature fuse 82 is provided, for example, on a power supply path between the first switching element 71 and the second switching element 72 and the second power supply terminal 62. The second temperature fuse 82 is provided, for example, on a power supply path between the first switching element 71 and the second switching element 72 and one AC output terminal of the power supply circuit 42. Accordingly, even when the heat exchanger 20 includes a plurality of heaters, the power supply path between the plurality of heaters and the second power supply terminal 62 can be appropriately opened only by one second temperature fuse 82.
However, when the heat exchanger 20 includes a plurality of heaters, the sanitary cleaning device 10 may include a plurality of second temperature fuses 82 respectively corresponding to the plurality of heaters of the heat exchanger 20. In this example, the sanitary cleaning device 10 may include, for example, two second temperature fuses 82 provided between the first heater 21 and the first switching element 71 and between the second heater 22 and the second switching element 72.
FIG. 6 is a cross-sectional view schematically showing a part of the sanitary cleaning device according to the embodiment.
FIG. 6 schematically shows a cross section taken along line A1-A2 in FIG. 2.
As shown in FIG. 6, the heater unit 112 of the heat exchanger 20 is provided at a position between the first temperature fuse 81 and the second temperature fuse 82. The first temperature fuse 81 and the second temperature fuse 82 are provided, for example, on both sides of the heater unit 112 across the central axis CL of the cylindrical heater unit 112 when viewed from above. In other words, the heater unit 112 is provided such that the central axis CL of the heater unit 112 is located between the first temperature fuse 81 and the second temperature fuse 82.
As shown in FIG. 6, the first temperature fuse 81 and the second temperature fuse 82 are provided at different positions in height from the heater unit 112, for example. The height of the second temperature fuse 82 with respect to the heater unit 112 is different from the height of the first temperature fuse 81 with respect to the heater unit 112. In this example, the first temperature fuse 81 is disposed at a position higher than the second temperature fuse 82. The first temperature fuse 81 is disposed above the central axis CL of the heater unit 112, for example. The second temperature fuse 82 is disposed below the central axis CL of the heater unit 112, for example.
Contrary to the above, the second temperature fuse 82 may be disposed at a position higher than the first temperature fuse 81. For example, one of the first temperature fuse 81 and the second temperature fuse 82 may be disposed above the central axis CL of the heater unit 112, and the other of the first temperature fuse 81 and the second temperature fuse 82 may be disposed below the central axis CL of the heater unit 112.
At least a part of the second temperature fuse 82 is provided, for example, at a point symmetrical position with at least a part of the first temperature fuse 81 about the central axis CL of the heater unit 112. For example, in a plane (cross section) orthogonal to the central axis CL of the heater unit 112, a distance D1 from the central axis CL of the heater unit 112 to the first temperature fuse 81 is substantially the same as a distance D2 from the central axis CL of the heater unit 112 to the second temperature fuse 82.
In FIG. 6, in a plane (cross section) orthogonal to the central axis CL of the heater unit 112, the distance from the central axis CL of the heater unit 112 to the center of the first temperature fuse 81 is defined as the distance D1, and the distance from the central axis CL of the heater unit 112 to the center of the second temperature fuse 82 is defined as the distance D2. The distance D1 from the central axis CL of the heater unit 112 to the first temperature fuse 81 is not limited to this, and may be a distance at any position of the first temperature fuse 81. Similarly, the distance D2 from the central axis CL of the heater unit 112 to the second temperature fuse 82 may be a distance at any position of the second temperature fuse 82. The first temperature fuse 81 and the second temperature fuse 82 only need to be provided at least partially at the same distance from the central axis CL of the heater unit 112.
However, the arrangement of the first temperature fuse 81 and the second temperature fuse 82 is not limited to the above. The arrangement of the first temperature fuse 81 and the second temperature fuse 82 may be any positions where the temperature of the heat exchanger 20 (heater unit 112) can be appropriately detected. The first temperature fuse 81 and the second temperature fuse 82 may be disposed so as to sandwich the heater unit 112 therebetween, for example. The first temperature fuse 81 and the second temperature fuse 82 are not necessarily disposed on both sides of the heater unit 112, and may be disposed close to one side of the heater unit 112. The arrangement of the first temperature fuse 81 and the second temperature fuse 82 may be appropriately set according to a direction in which the heat exchanger 20 is attached to the sanitary cleaning device 10, a direction of water flowing inside the heat exchanger 20, and the like.
FIG. 7 is a circuit diagram showing a part of a reference sanitary cleaning device.
FIG. 7 schematically shows a part of the reference sanitary cleaning device in which the second temperature fuse 82 is omitted and only the first temperature fuse 81 is provided.
As shown in FIG. 7, in the configuration of the reference sanitary cleaning device, when a dielectric breakdown occurs between water flowing inside and the first heater 21 or the second heater 22, and the first temperature fuse 81 is fused by abnormal heat generation, a current may flow from the first heater 21 or the second heater 22 to the ground side via the water inside depending on a position where the dielectric breakdown occurs.
FIG. 7 shows a case where dielectric breakdown occurs on one end side of the second heater 22 close to the first power supply terminal 61 between water flowing inside and the second heater 22. In this case, if the connection between the connecting portion 60 and the power supply PS is erroneously connected and the second power supply terminal 62 is connected to the power line side of the power supply PS, as indicated by an arrow A1 in FIG. 7, a current flows from the second power supply terminal 62 to the ground electrode 134 through water inside the heat exchanger 20 from the second switching element 72, the second heater 22, and the dielectric breakdown portion. In this case, the current continues to flow through the second heater 22 even after the fusing of the first temperature fuse 81, and there is a possibility that the heat generation of the second heater 22 cannot be appropriately stopped.
On the other hand, in the sanitary cleaning device 10 according to the present embodiment, the heat exchanger 20 includes the ground electrode 134 which grounds the water flowing inside. As a result, even if dielectric breakdown occurs between the water flowing inside and the first heater 21 and the second heater 22, it is possible to suppress the influence of the current leakage from the first heater 21 and the second heater 22 to the water on the human body through the water, and to enhance the safety against the electric leakage from the first heater 21 and the second heater 22.
The sanitary cleaning device 10 further includes the first temperature fuse 81 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, and the second temperature fuse 82 provided on a 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. As a result, when abnormal heat generation occurs due to dielectric breakdown between the water flowing inside and the first heater 21 and the second heater 22, the power supply paths are opened by the first temperature fuse 81 and the second temperature fuse 82, so that the heat generation of the first heater 21 and the second heater 22 can be appropriately stopped even if the dielectric breakdown occurs at any position. By opening the power supply paths at both ends of the first heater 21 and the second heater 22, it is possible to suppress the current from continuing to flow through the first heater 21 and the second heater 22 even after the power supply paths are opened by the first temperature fuse 81 and the second temperature fuse 82.
Accordingly, it is possible to provide the sanitary cleaning device 10 capable of more appropriately stopping the heat generation of the first heater 21 and the second heater 22 while enhancing the safety against the electric leakage from the first heater 21 and the second heater 22 even when the dielectric breakdown occurs between the water flowing inside and the first heater 21 and the second heater 22 in the instantaneous heat exchanger 20.
In the sanitary cleaning device 10, the heater unit 112 is disposed at a position between the first temperature fuse 81 and the second temperature fuse 82. Accordingly, even if temperature unevenness is generated in the surface temperature of the heater unit 112, the sanitary cleaning device 10 can easily detect the abnormality of the high temperature, and can quickly stop the heat generation of the first heater 21 and the second heater 22 at the time of the abnormality.
In the instantaneous heat exchanger 20, a relatively high-output heater is used. Therefore, in the instantaneous heat exchanger 20, when temperature unevenness occurs, there is a possibility that a temperature difference at each place increases. For example, the temperature tends to be higher on the downstream side of the flow path inside the heat exchanger 20 than on the upstream side of the flow path inside the heat exchanger 20. In addition, for example, the temperature tends to be higher at a high position of the flow path inside the heat exchanger 20 than at a low position of the flow path inside the heat exchanger 20. Furthermore, when a plurality of heaters are provided in the heater unit 112, temperature unevenness may occur depending on a position where each heater is provided or a combination of heaters to be used. In the sanitary cleaning device 10, the heater unit 112 is disposed at a position between the first temperature fuse 81 and the second temperature fuse 82. Accordingly, even if such temperature unevenness occurs, the abnormality of the high temperature can be easily detected, and the heat generation of the first heater 21 and the second heater 22 can be stopped quickly at the time of the abnormality.
In the sanitary cleaning device 10, the first temperature fuse 81 and the second temperature fuse 82 are disposed at different positions in height from the heater unit 112. As a result, even if temperature unevenness occurs in the surface temperature in the height direction of the heater unit 112, the abnormality of the high temperature can be easily detected, and the heat generation of the heater can be stopped quickly at the time of the abnormality.
Further, in the sanitary cleaning device 10, at least a part of the second temperature fuse 82 is disposed at a position point-symmetrical to at least a part of the first temperature fuse 81 about the central axis CL of the heater unit 112. As a result, even if temperature unevenness occurs in the surface temperature of the heater unit 112, the abnormality of the high temperature can be more easily detected, and the heat generation of the first heater 21 and the second heater 22 can be stopped more quickly at the time of the abnormality.
In the above embodiment, the cylindrical heater unit 112 is shown. The shape of the heater unit 112 is not limited to this, and may be, for example, a rectangular parallelepiped shape. In this example, water is brought into contact with the inner surface side and the outer surface side of the cylindrical heater unit 112 to perform heating. The heater unit 112 may have an internal space and be configured such that water is brought into contact only with the inner surface or water is brought into contact only with the outer surface. The heater unit 112 may have, for example, a rod-like shape having no internal space. The shape of the heater unit 112 may be any shape that can appropriately heat water.
The central axis CL of the heater unit 112 may be any axis passing through the center of the heater unit 112. For example, when the heater unit 112 has an amorphous shape, an axis passing through an intersection of the center of the heater unit 112 in the left-right direction and the center in the up-down direction may be set as the central axis CL.
The embodiment of the present invention has been described above. However, the present invention is not limited to these descriptions. Regarding the above-described embodiment, those to which design changes are appropriately made by those skilled in the art are also included in the scope of the present invention as long as they have the features of the present invention. For example, a shape, a size, a material, an arrangement, and the like of each element included in the sanitary cleaning device 10 and the like are not limited to those exemplified, and can be appropriately changed.
In addition, each element included in the above-described embodiment can be combined as far as technically possible, and a combination thereof is also included in the scope of the present invention as long as it has the features of the present invention.

Reference Signs List

10: sanitary cleaning device
12: flow path
14: electromagnetic valve
20: heat exchanger
21: first heater
22: second heater
30: jet nozzle
32: jet port
33: flow rate switching valve
34: flow path switching valve
36: nozzle cleaning chamber
38: nozzle motor
40: control unit
42: power supply circuit
50: operation unit
60: connecting portion
61: first power supply terminal
62: second power supply terminal
71: first switching element
72: second switching element
74: current fuse
81: first temperature fuse
82: second temperature fuse
112: heater unit
114: case
116: shaft core member
118: coil spring
120: case body
122: lid portion
124: coil spring
130: outer flow path
132: inner flow path
134: ground electrode
140: water passing member
PS: power supply
WS: water supply source

Claims

A sanitary cleaning device comprising:
a connecting portion including a first power supply terminal and a second power supply terminal, the connecting portion being electrically connected to an AC power supply via the first power supply terminal and the second power supply terminal;

a heat exchanger including a ground electrode that grounds water flowing inside, and a heater unit having a heater electrically insulated from the water flowing inside, in which 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, so that cleaning water supplied from a water supply source is heated by the heater based on AC power supplied from the power supply to the heater via the connecting portion;

a jet nozzle that jets cleaning water supplied through the heat exchanger;

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 switches between a state in which the AC power is supplied to the heater and a state in which supply of the AC power to the heater is stopped;

a control unit that controls switching of the switching element to control supply of the AC power to the heater;

a first temperature fuse provided on a power supply path between one end of the heater and the first power supply terminal, the first temperature fuse opening the power supply path between the one end of the heater and the first power supply terminal when a temperature of the heat exchanger becomes equal to or higher than a predetermined temperature; and

a second temperature fuse provided on the power supply path between the other end of the heater and the second power supply terminal, the second temperature fuse opening the power supply path between the other end of the heater and the second power supply terminal when a temperature of the heat exchanger becomes equal to or higher than a predetermined temperature.
The sanitary cleaning device according to claim 1, wherein the heater unit is provided at a position between the first temperature fuse and the second temperature fuse.
The sanitary cleaning device according to claim 1 or 2, wherein the first temperature fuse and the second temperature fuse are provided at positions different in height from the heater unit.
The sanitary cleaning device according to claim 3, wherein at least a part of the second temperature fuse is provided at a position point-symmetrical to at least a part of the first temperature fuse about a central axis of the heater unit.