JP7272170B2 - sanitary washing equipment - Google Patents

Description

The disclosed embodiments relate to sanitary washing devices.

2. Description of the Related Art Conventionally, in a sanitary washing apparatus that discharges hot water toward the private parts of a human body, for example, the temperature of washing water in a hot water storage tank is set in advance by controlling the on/off of a heater that heats the washing water stored in the hot water storage tank. There is a hot water storage type that performs heat retention control to maintain the target temperature. Such a sanitary washing apparatus is equipped with a safety device that shuts off the power supply to the heater when the temperature is high in order to prevent the washing water from becoming hot.

Such safety devices include mechanical devices such as bimetal switches. In a hot water storage type sanitary washing device, the temperature of the cleaning water in the hot water storage tank rises faster when the heater is turned on due to the miniaturization and high performance of the hot water storage tank. It takes time to warm up and the wash water in the hot water tank may rise to an unsafe temperature.

On the other hand, in a momentary sanitary washing device that uses a ceramic heater or the like to heat the washing water in a short time at the start of washing, electronic control is capable of instantaneously shutting off the electricity to the heater according to the temperature of the washing water. It is known to use a limit thermistor, which is a temperature sensor of the formula (see Patent Document 1, for example).

Japanese Patent No. 6284070

Here, it is conceivable to use a limit thermistor used in a momentary sanitary washing apparatus as a temperature sensor for a safety device in a hot water storage type sanitary washing apparatus.

However, when the limit thermistor is applied to the hot water storage type, the change in the temperature of the wash water in the hot water storage tank is smaller than that of the instantaneous type. value) may hardly change, and there is a risk that failures in which the resistance value of the limit thermistor is fixed (this is called a fixed resistance value) cannot be detected.

One aspect of the embodiments has been made in view of the above, and an object thereof is to provide a sanitary washing device capable of detecting fixation of the resistance value of the limit thermistor under conditions where temperature changes are small.

A sanitary washing device according to an aspect of an embodiment includes a hot water storage tank that stores wash water, a hot water storage tank that stores wash water, a nozzle that discharges the wash water in the hot water storage tank toward the private parts of a human body, and the hot water storage. a heater that heats the wash water in the tank; a first temperature sensor that measures the temperature of the wash water in the hot water storage tank and uses the measured value for on/off control of the heater; and the temperature of the wash water in the hot water storage tank. a second temperature sensor whose measured value is used to determine whether the temperature of the cleaning water discharged from the nozzle is higher than a predetermined temperature; and the heater is operated based on the measured value of the first temperature sensor. a control unit that performs heat retention control for maintaining the temperature of the wash water in the hot water storage tank at the target temperature by on/off control, the second temperature sensor being a limit thermistor, and the control unit In the heat retention control, the heater is controlled to turn on, and after determining whether or not the temperature of the wash water in the hot water storage tank has reached the target temperature, the heater is turned off to control the temperature of the wash water in the hot water tank. reaches a preset first temperature that is lower than the target temperature, a failure determination of the second temperature sensor is made based on the amount of change in the measured value of the second temperature sensor.

According to such a configuration, it is possible to detect a failure (fixed resistance value) in which the measured value (resistance value) of the second temperature sensor (limit thermistor) that functions as a safety device does not change. In this way, it is possible to detect the fixation of the resistance value of the limit thermistor under conditions where temperature changes are small in a hot water storage type sanitary washing device. Safety can be improved, for example, prevention of ejection can be achieved.

In the sanitary washing apparatus described above, in the heat retention control, the control unit turns on the heater to determine whether or not the temperature of the washing water in the hot water storage tank has reached the target temperature. When the temperature of the wash water in the hot water storage tank reaches the first temperature by turning off the heater, and when the amount of change in the measured value of the second temperature sensor does not reach the predetermined amount of change, the stored hot water The heater is kept off until the temperature of the wash water in the tank reaches a preset second temperature lower than the first temperature.

According to such a configuration, it is possible to detect the fixation of the resistance value of the limit thermistor, and furthermore, by setting the heater ON control start point to a lower temperature, the fixation of the resistance value of the limit thermistor can be more reliably fixed. can be detected.

In the sanitary washing apparatus described above, in the heat retention control, the control unit turns on the heater to determine whether or not the temperature of the washing water in the hot water storage tank has reached the target temperature. When the temperature of the wash water in the hot water storage tank reaches the first temperature by controlling the heater to be off, the heater is controlled to be off until the amount of change in the measured value of the second temperature sensor reaches a predetermined amount of change. continue.

According to such a configuration, it is possible to detect the fixation of the resistance value of the limit thermistor, and more reliably detect the fixation of the resistance value of the limit thermistor while suppressing a decrease in the temperature of the cleaning water discharged from the nozzle. can be done.

According to one aspect of the embodiment, it is possible to detect the fixation of the resistance value of the limit thermistor under conditions where the temperature change is small.

FIG. 1 is a schematic perspective view of a toilet apparatus equipped with a sanitary washing device according to an embodiment. FIG. 2 is a block diagram showing an example of the configuration of the sanitary washing device according to the embodiment. FIG. 3 is an explanatory diagram of the hot water storage tank. FIG. 4 is an explanatory diagram of heat retention control. FIG. 5 is an explanatory diagram of failure determination. FIG. 6 is a flowchart showing an example of a processing procedure for fault determination. FIG. 7 is an explanatory diagram of a modification of failure determination.

Hereinafter, embodiments of the sanitary washing device disclosed in the present application will be described in detail with reference to the accompanying drawings. In addition, this invention is not limited by embodiment shown below.

<Overview of toilet equipment>
First, an overview of a toilet apparatus 10 including a sanitary washing apparatus 20 according to an embodiment will be described with reference to FIG. FIG. 1 is a schematic perspective view of a toilet device 10 having a sanitary washing device 20 according to an embodiment.

For convenience of explanation, FIG. 1 shows a three-dimensional orthogonal coordinate system including the Z-axis whose positive direction is vertically upward (upward). On the other hand, the positive direction of the Y-axis is defined as the front, and the negative direction of the Y-axis is defined as the rear. Therefore, hereinafter, the X-axis direction may be referred to as the left-right direction, the Y-axis direction as the front-rear direction, and the Z-axis direction as the up-down direction.

In addition, the expression "washing water" below does not necessarily mean cold water, but may be used to mean hot water. As shown in FIG. 1, the toilet apparatus 10 is installed in the toilet room 1. As shown in FIG. The toilet device 10 includes a western-style toilet bowl (hereinafter referred to as toilet bowl) 11 , a flush water tank 12 , and a sanitary washing device 20 .

Toilet bowl 11 is made of, for example, ceramics. The toilet bowl 11 may be made of resin, or may be manufactured by combining pottery and resin. In the illustrated example, the toilet bowl 11 is installed on the floor of the toilet room 1, which is a so-called floor-standing type.

The flush water tank 12 is installed at the upper rear portion of the toilet bowl 11 . The flush water tank 12 stores flush water to be supplied to a bowl portion (not shown) that receives waste in the toilet bowl 11 . As described above, the toilet apparatus 10 is a so-called tank type in which the bowl portion of the toilet 11 is washed with the flush water stored in the flush water tank 12 (to be distinguished from the flush water, this will be referred to as toilet bowl flush water). be.

The toilet device 10 is not limited to a tank type, and may be, for example, a water supply direct pressure type that directly uses the water supply pressure of tap water, a flush valve type, or a flush valve type that utilizes the pressure of a pump to supply flush water. It may be something that is supplied.

The sanitary washing device 20 is installed in the upper rear portion of the toilet bowl 11, for example, in front of the flush water tank 12. As shown in FIG. The sanitary washing device 20 includes a body portion 21, a toilet lid 22, and a toilet seat (not shown). Both the toilet lid 22 and the toilet seat are attached to the body portion 21 so as to be openable and closable. The body portion 21 includes a case 21a. The case 21a accommodates a nozzle 90 (see FIG. 2) and the like, which will be described later.

<Configuration of sanitary washing device>
Next, the configuration of the sanitary washing device 20 according to the embodiment will be described with reference to FIG. FIG. 2 is a block diagram showing an example of the configuration of the sanitary washing device 20 according to the embodiment. As shown in FIG. 2, the sanitary washing device 20 includes a water supply path 30, a valve unit 40, a hot water storage tank 50, a heater 51, an electrolytic cell unit 60, a vacuum breaker 70, a switching valve 80, a nozzle 90, and a and

The sanitary washing device 20 has temperature sensors 101 and 102 . The sanitary washing device 20 also includes a control section 200 and a storage section 250 . The water supply path 30, the valve unit 40, the hot water tank 50, the electrolytic cell unit 60, the vacuum breaker 70, the switching valve 80, the nozzle 90, the control section 200 and the storage section 250 are arranged inside the case 21a (see FIG. 1). Heater 51 and temperature sensors 101 and 102 are arranged in hot water storage tank 50 .

The water supply channel 30 connects a water supply source (for example, a water pipe) A to the nozzle 90 . Water (cleaning water) supplied from the water supply source A flows through the water supply path 30 . A valve unit 40, a hot water storage tank 50, an electrolytic cell unit 60, a vacuum breaker 70, and a switching valve 80 are arranged in order from the upstream side (water supply source A side) of the water supply path 30 .

The valve unit 40 is driven according to a control signal output from the control section 200 to open and close the water supply passage 30 . The hot water storage tank 50 stores wash water. The wash water stored in the hot water storage tank 50 is heated by the heater 51 and the temperature is measured by the temperature sensors 101 and 102 . Note that the hot water storage tank 50 will be described later with reference to FIG.

The electrolytic cell unit 60 comprises, for example, an anode plate and a cathode plate within an electrolytic cell. The electrolytic cell unit 60 is driven according to a control signal output from the control unit 200, and electrolyzes the cleaning water flowing in the electrolytic cell to produce cleaning water containing hypochlorous acid (also called functional water). Generate.

The vacuum breaker 70 causes the washing water to flow back through the water supply passage 30 when negative pressure is generated in the water supply passage 30, through an atmosphere release passage (not shown), so that the washing water flows back from the nozzle 90 to the hot water storage tank 50 or the like. to prevent

The switching valve 80 is driven according to a control signal output from the control unit 200 to switch the outflow destination of the washing water flowing through the water supply passage 30 . The switching valve 80 switches the outflow destination of the cleansing water flowing through the water supply path 30 to, for example, one of a plurality of water outlets (not shown) of the nozzle 90 . Also, the switching valve 80 switches the outflow destination of the cleaning water flowing through the water supply path 30 to, for example, the nozzle cleaning channel 85 . The cleaning water flowing through the nozzle cleaning channel 85 is discharged toward the surface of the nozzle 90 for cleaning the nozzle 90 .

The nozzle 90 discharges cleansing water in the hot water storage tank 50 toward the private parts of the user (human body parts) seated on the toilet seat. The nozzle 90 can move forward and backward with respect to the case 21a. Specifically, the nozzle 90 is connected to a driving source (not shown) such as a nozzle motor, and moves from the position where it extends from the case 21a into the bowl portion of the toilet bowl 11 to the position where it retreats so as to be stored inside the case 21a. advance and retreat between The nozzle 90 discharges the cleansing water W1 toward the user's private parts at the advanced position to clean the human body private parts.

The temperature sensor comprises a first temperature sensor 101 and a second temperature sensor 102 . Both the first temperature sensor 101 and the second temperature sensor 102 measure the temperature of the wash water in the hot water storage tank 50 .

The first temperature sensor 101 is a hot water thermistor. A measurement result (hereinafter referred to as a measured value or a resistance value) by the first temperature sensor (hereinafter referred to as a hot water thermistor) 101 is used for driving control of the heater 51, that is, for on/off control.

The second temperature sensor 102 is an electronically controllable limit thermistor. A second temperature sensor (hereinafter referred to as a limit thermistor) 102 is provided to confirm that the temperature of the wash water discharged from the nozzle 90 is safe for the human body, for example. Therefore, the measurement result of the limit thermistor 102 (hereinafter referred to as the measurement value or resistance value) is used to determine whether or not the temperature of the cleaning water discharged from the nozzle 90 is higher than a predetermined temperature. Thus, limit thermistor 102 functions as a safety device.

The measured values of hot water thermistor 101 and limit thermistor 102 are output to controller 200 . The measured values of hot water thermistor 101 and limit thermistor 102 are expressed, for example, by digital values of 0 to 255 (hereinafter referred to as AD values). Control unit 200 converts the AD value output from limit thermistor 102 or the like into temperature using a conversion table stored in advance in storage unit 250 . For example, when the AD value output from the limit thermistor 102 or the like is 100, the temperature is 40.degree.

The control unit 200 is implemented by, for example, executing a program stored in the storage unit 250 using a CPU (Central Processing Unit), an MPU (Micro Processing Unit), or the like, using a RAM (Random Access Memory) as a work area. be. Note that the control unit 200 can also be implemented by an integrated circuit such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array).

The control unit 200 controls the valve unit 40, the hot water storage tank 50, the electrolytic cell unit 60, the switching valve 80, etc. based on various signals that are input. Storage unit 250 is implemented by, for example, a semiconductor memory device such as RAM (Random Access Memory) or flash memory.

The control unit 200 performs heat retention control to maintain the temperature of the wash water in the hot water storage tank 50 at a preset target temperature T0 (see FIG. 4) by controlling the on/off of the heater 51 based on the measured value of the hot water thermistor 101. I do.

When the measured value of the limit thermistor 102 is equal to or higher than a predetermined threshold, the control unit 200 determines that the temperature of the wash water flowing out of the hot water storage tank 50 exceeds a safe temperature for the human body. In this case, the controller 200 stops the temperature control by the heater 51 and does not heat the washing water. Note that the control unit 200 may control the valve unit 40 to forcibly stop the discharge of cleaning water when the measured value of the limit thermistor 102 is equal to or greater than a predetermined threshold value.

The determination unit 201 determines whether or not a failure occurs in the limit thermistor 102 set as a failure diagnosis target. The failure determination of the limit thermistor 102 by the determination unit 201 will be described later with reference to FIGS. 5 and 6. FIG.

The heat retention control unit 202 controls the heater 51 on and off within a predetermined temperature range so that the temperature of the wash water in the hot water storage tank 50 is maintained at a preset target temperature T0. Note that the heat retention control by the heat retention control unit 202 will be described later using FIG. 4 .

<Hot water storage tank>
Next, the hot water storage tank 50 will be described with reference to FIG. FIG. 3 is an explanatory diagram of the hot water storage tank 50 and a schematic diagram of the hot water storage tank 50. As shown in FIG. As described above, heater 51 and temperature sensors (hot water thermistor 101 and limit thermistor 102) are arranged in hot water storage tank 50 .

As shown in FIG. 3 , the hot water storage tank 50 has an inlet 52 and an outlet 53 . The inflow port 52 allows wash water to flow into the hot water storage tank 50 from the upstream side of the hot water storage tank 50 . The outflow port 53 causes wash water to flow out from the inside of the hot water storage tank 50 to the downstream side of the hot water storage tank 50 . The heater 51 is arranged at a position closer to the inlet 52 than to the outlet 53 .

Hot water thermistor 101 and limit thermistor 102 measure the temperature of the wash water as described above. Hot water thermistor 101 is arranged at a position closer to inlet 52 than limit thermistor 102 in hot water storage tank 50 . Limit thermistor 102 is arranged at a position closer to outflow port 53 than hot water thermistor 101 in hot water storage tank 50 .

When the wash water in the hot water storage tank 50 is heated by the heater 51 , the temperature starts rising near the inlet 52 near the heater 51 . The heated cleansing water W2 starts convection, and the temperature of the cleansing water in the hot water storage tank 50 near the outflow port 53 gradually rises. Therefore, while the heater 51 is on-controlled, the temperature of the wash water near the inlet 52 tends to be higher than that near the outlet 53 .

When the control unit 200 (see FIG. 2) detects that the temperature of the wash water in the hot water storage tank 50 is higher than a predetermined temperature based on the measurement value of the limit thermistor 102, the control unit 200 turns off the heater 51, and the solenoid valve close control. In addition to such a software configuration, a hardware configuration that closes the electromagnetic valve via a circuit (for example, a comparator circuit) may be used.

<Washing water heat retention control>
Next, referring to FIG. 4, the heat retention control of the wash water in the hot water storage tank 50 will be described. FIG. 4 is an explanatory diagram of heat retention control, and is a timing chart showing the relationship between ON/OFF control of heater 51 and measured values V1 and V2 of temperature sensors (hot water thermistor 101 and limit thermistor 102) during heat retention control.

As shown in FIG. 4, the heat retention control unit 202 (see FIG. 2) allows the temperature of the wash water in the hot water storage tank 50 (see FIG. 2) (that is, the measured value V1 of the hot water thermistor 101) to be set in advance by the user or the like. The heater 51 (see FIG. 2) is on/off controlled within a predetermined temperature range so that the target temperature T0 is obtained.

After heating the wash water by starting power supply to the heater 51 (turning on the heater 51), the heat retention control unit 202 detects that the measured value V1 of the hot water thermistor 101 exceeds the target temperature T0. 51 is stopped (the heater 51 is turned off). By turning off the heater 51, the wash water is naturally cooled.

When the heat retention control unit 202 detects that the measured value V1 of the hot water thermistor 101 has fallen below a preset first temperature T1 that is lower than the target temperature T0, it restarts energizing the heater 51 (heater 51 on). In this manner, the heat retention control unit 202 repeats heating and cooling of the cleansing water so that the temperature of the cleansing water in the hot water storage tank 50 is maintained at the target temperature T0.

In the present embodiment, on/off control of the heater 51 is performed by starting and stopping power supply to the heater 51. It is also possible to perform on/off control of the heater 51 .

Here, in the heat retention control as described above, since the temperature change of the wash water in the hot water storage tank 50 is small, even if the limit thermistor 102 is normal, the measured value (resistance value) V2 of the limit thermistor 102 hardly changes. There is Therefore, even if a fixed failure of the resistance value V2 occurs in the limit thermistor 102, it may not be possible to determine whether the limit thermistor 102 is normal or abnormal (failure).

Further, when the resistance value V2 is fixed in the limit thermistor 102, the resistance value V2 does not change even if the temperature of the washing water actually rises or falls. , there is a possibility that hot cleaning water may be discharged, which reduces safety. For this reason, in the present embodiment, the controller 200 determines whether the resistance value of the limit thermistor 102 functioning as a safety device is fixed.

<Determination of limit thermistor failure>
Next, failure determination of the limit thermistor 102 by the control unit 200 will be described with reference to FIGS. 5 and 6. FIG. FIG. 5 is an explanatory diagram of failure determination, and is a timing chart showing the relationship between ON/OFF control of heater 51 and measured values V1 and V2 of temperature sensors (hot water thermistor 101 and limit thermistor 102). FIG. 6 is a flowchart showing an example of a processing procedure for fault determination.

As shown in FIG. 5, when control unit 200 (heat retention control unit 202) detects that measured value V1 of hot water thermistor 101 exceeds target temperature T0, it controls heater 51 to turn off the measured value V1 of hot water thermistor 101. However, for example, when the temperature drops below the first temperature T1, the heater 51 is repeatedly turned on to perform heat retention control to keep the temperature of the wash water in the hot water storage tank 50 at the target temperature T0.

During the heat retention control by the heat retention control unit 202, the temperature change of the wash water in the hot water storage tank 50 is small, so the measured value (resistance value) V2 of the limit thermistor 102 hardly changes. On the other hand, if the resistance value V2 of the limit thermistor 102 does not change, there is a possibility that the limit thermistor 102 is malfunctioning (fixed resistance value V2).

Therefore, as shown in the measurement range TR in the drawing, the control unit 200 controls the heater 51 to turn on and after the measured value V1 of the hot water thermistor 101 reaches the target temperature T0, controls the heater 51 to turn off the hot water. At time point P1 when the measured value V1 of the thermistor 101 reaches a first temperature T1 lower than the target temperature T0, failure determination of the limit thermistor 102 is performed based on the amount of change in the resistance value V2 of the limit thermistor 102.

Specifically, the control unit 200 controls the limit thermistor 102 if the amount of change in the resistance value V2 of the limit thermistor 102 reaches a predetermined amount of change at the point P1 when the measured value V1 of the hot water thermistor 101 reaches the first temperature T1. 102 is determined to be normal.

On the other hand, if the amount of change in the resistance value V2 of the limit thermistor 102 does not reach the predetermined amount of change at the time point P1 when the measured value V1 of the hot water thermistor 101 reaches the first temperature T1, the control unit 200 stops the limit thermistor 102 determined to be a failure.

Further, the failure determination processing of the limit thermistor 102 is performed, for example, by the procedure shown in FIG. As shown in FIG. 6, first, the determination unit 201 of the control unit 200 determines whether or not the cleaning water is being kept warm (step S101). That is, the determination unit 201 of the control unit 200 determines whether or not the temperature control of the wash water in the hot water storage tank 50 is being performed.

When the determination unit 201 determines that the washing water is being kept warm (step S101: Yes), the determination unit 201 determines whether the measured value V1 of the hot water thermistor 101 has reached the target temperature T0. (step S102). When the determination unit 201 determines that the measured value V1 of the hot water thermistor 101 has reached the target temperature T0 (step S102: Yes), the control unit 200 turns off the heater 51 (step S103).

If the determination unit 201 determines in the process of step S102 that the measured value V1 of the hot water thermistor 101 has not reached the target temperature T0 (step S102: No), the control unit 200 continues the process until the target temperature T0 is reached. repeat. In this manner, the control unit 200 performs heat retention control of the wash water in the hot water storage tank 50 .

Next, after turning off the heater 51, the controller 200 determines whether or not the measured value V1 of the hot water thermistor 101 reaches the first temperature T1 lower than the target temperature T0 (step S104). .

When the determination unit 201 determines that the measured value V1 of the hot water thermistor 101 has reached the first temperature T1, the control unit 200 determines that the measurement range TR (see FIG. 5) from the ON control of the heater 51 to the next ON control. It is determined whether or not the amount of change in the measured value (resistance value) V2 of the limit thermistor 102 is less than a predetermined amount of change, that is, whether or not the amount of change in the resistance value V2 has reached the predetermined amount of change (step S105). .

When the determination unit 201 determines that the amount of change in the resistance value V2 of the limit thermistor 102 is less than the predetermined amount of change, that is, the amount of change in the resistance value V2 has not reached the predetermined amount of change (step S105). : Yes), the determination unit 201 determines that the fixed failure of the resistance value V2 has occurred in the limit thermistor 102 (step S106), and terminates the failure determination process.

When it is determined that the limit thermistor 102 is out of order in the process of step S106, the control unit 200 takes a safer approach, such as continuing to turn off the heater 51 or prohibiting the discharge of cleaning water from the nozzles 90. perform control aimed at.

If the determination unit 201 determines in the process of step S104 that the measured value V1 of the hot water thermistor 101 has not reached the first temperature T1 (step S105: No), the control unit 200 reaches the first temperature T1. Repeat the process until

In addition, in the processing of step S105, the control unit 200 determines that the amount of change in the resistance value V2 of the limit thermistor 102 is equal to or greater than the predetermined amount of change, that is, the amount of change in the resistance value V2 has reached the predetermined amount of change. (step S105: No), for example, the process returns to step S102, for example, heater 51 is turned on to continue heat retention control.

According to the sanitary washing device 20 according to the embodiment, it is possible to detect a fixed failure of the resistance value V2 of the limit thermistor 102 functioning as a safety device, in which the resistance value V2 does not change. In this way, the fixation of the resistance value V2 of the limit thermistor 102 can be detected under conditions where the temperature change is small in the hot water storage type, and high-temperature wash water heated to a temperature unsafe for the human body is discharged from the nozzle 90. safety can be improved.

Here, returning to FIG. 5, as shown in FIG. 5, the control unit 200 may add a second temperature T2 that is lower than the first temperature T1.

As shown in FIG. 5, after the controller 200 turns on the heater 51 and the measured value V1 of the hot water thermistor 101 reaches the target temperature T0, the controller 200 turns off the heater 51 so that the measured value V1 of the hot water thermistor 101 reaches the target temperature T0. If the amount of change in the resistance value V2 of the limit thermistor 102 has not reached the predetermined amount of change at the time point P1 when the temperature reaches the first temperature T1, the heater 51 continues until the measured value V1 of the hot water thermistor 101 reaches the second temperature T2. off control is continued.

The control unit 200 determines that the limit thermistor 102 is normal when the amount of change in the resistance value V2 of the limit thermistor 102 reaches a predetermined amount of change TW1 from the point P2 when the measured value V1 of the hot water thermistor 101 reaches the second temperature T2. If the amount of change in the resistance value V2 of the limit thermistor 102 does not reach a predetermined amount of change TW1, it is determined that the limit thermistor 102 is out of order.

According to such a configuration, it is possible to detect that the resistance value V2 of the limit thermistor 102 is fixed. can be increased, and fixing of the resistance value V2 can be detected more reliably.

Also, as shown in FIG. 5, the control unit 200 may add a preset third temperature that is lower than the second temperature.

As shown in FIG. 5, after the controller 200 turns on the heater 51 and the measured value V1 of the hot water thermistor 101 reaches the target temperature T0, the controller 200 turns off the heater 51 so that the measured value V1 of the hot water thermistor 101 reaches the target temperature T0. If the amount of change in the resistance value V2 of the limit thermistor 102 has not reached the predetermined amount of change TW1 from the time point P2 when the temperature reaches the second temperature T2, the heater temperature is maintained until the measured value V1 of the hot water thermistor 101 reaches the third temperature T3. 51 off control is continued.

The control unit 200 determines that the limit thermistor 102 is normal when the amount of change in the resistance value V2 of the limit thermistor 102 reaches a predetermined amount of change after the measured value V1 of the hot water thermistor 101 reaches the third temperature T3. If the amount of change in the resistance value V2 of the limit thermistor 102 does not reach a predetermined amount of change, it is determined that the limit thermistor 102 is out of order.

According to such a configuration, it is possible to detect that the resistance value V2 of the limit thermistor 102 is fixed. , the fluctuation of the resistance value V2 of the limit thermistor 102 can be increased, and the fixation of the resistance value V2 can be detected more reliably.

The control unit 200 detects the failure of the limit thermistor 102 based on the relationship between the n-1 (n is an integer equal to or greater than 2) temperature and the n-th temperature. It should be noted that the temperatures expressed using an integer n of 2 or more (first temperature, second temperature, third temperature, fourth temperature, . . . ) are lower as the number increases. In this manner, the control unit 200 can increase the number of determinations while lowering the temperature for failure determination of the limit thermistor 102 .

FIG. 7 is an explanatory diagram of a modification of failure determination. As shown in FIG. 7, when the measured value V1 of the hot water thermistor 101 reaches the first temperature T1, the control unit 200 controls the amount of change in the resistance value V2 of the limit thermistor 102 to reach the predetermined amounts of change TW2 and TW3. , the off control of the heater 51 is continued.

After the heater 51 is turned on and the measured value V1 of the hot water thermistor 101 reaches the target temperature T0, the control unit 200 turns on the limit thermistor 102 at timing t1 when the measured value V1 of the hot water thermistor 101 falls below the first temperature T1. If the amount of change in the resistance value V2 has not reached the predetermined amount of change TW2, the off control of the heater 51 is continued. In other words, ON control of the heater 51 is suspended.

Control unit 200 determines that limit thermistor 102 is normal at timing t2 when the amount of change in resistance value V2 of limit thermistor 102 reaches predetermined amount of change TW2, and turns heater 51 on.

Further, as shown in FIG. 7, the control unit 200 controls the heater 51 to turn on, and immediately after the measured value V1 of the hot water thermistor 101 reaches the target temperature T0, controls the heater 51 to turn off and immediately turns off the limit thermistor 102. When the amount of change reaches the predetermined amount of change TW3, the limit thermistor 102 is determined to be normal at this timing t3, and the heater 51 is turned on at timing t4 when the measured value V1 of the hot water thermistor 101 next falls below the first temperature T1. on control.

According to such a configuration, it is possible to detect that the resistance value V2 of the limit thermistor 102 is fixed. Since it is possible to determine the failure of the limit thermistor 102 at the temperature T1, it is possible to more reliably detect the fixation of the resistance value of the limit thermistor 102 while suppressing the temperature drop of the cleaning water discharged from the nozzle 90 .

Further effects and modifications can be easily derived by those skilled in the art. Therefore, the broader aspects of the invention are not limited to the specific details and representative embodiments so shown and described. Accordingly, various changes may be made without departing from the spirit or scope of the general inventive concept defined by the appended claims and equivalents thereof.

20 sanitary washing device 50 hot water storage tank 51 heater 90 nozzle 101 first temperature sensor 102 second temperature sensor (limit thermistor)
200 control unit T0 target temperature T1 first temperature T2 second temperature V1 measured value of first temperature sensor V2 measured value of second temperature sensor

Claims (3)

a hot water storage tank for storing wash water;
a nozzle for discharging the cleansing water in the hot water storage tank toward the private parts of the human body;
a heater for heating the wash water in the hot water storage tank;
a first temperature sensor that measures the temperature of the wash water in the hot water storage tank and uses the measured value for on/off control of the heater;
a second temperature sensor that measures the temperature of the wash water in the hot water storage tank and uses the measured value to determine whether the temperature of the wash water discharged from the nozzle is higher than a predetermined temperature;
a control unit that performs heat retention control to maintain the temperature of the wash water in the hot water storage tank at a target temperature by controlling the on/off of the heater based on the measured value of the first temperature sensor;
the second temperature sensor is a limit thermistor,
In the heat retention control, the control unit turns on the heater to determine whether or not the temperature of wash water in the hot water storage tank has reached the target temperature, and then turns off the heater to turn off the hot water storage tank. when the temperature of the wash water inside reaches a preset first temperature that is lower than the target temperature, determining a failure of the second temperature sensor based on the amount of change in the measured value of the second temperature sensor; Sanitary cleaning equipment. In the heat retention control, the control unit turns on the heater to determine whether or not the temperature of wash water in the hot water storage tank has reached the target temperature, and then turns off the heater to turn off the hot water storage tank. When the temperature of the wash water in the hot water storage tank reaches the first temperature, and when the amount of change in the measured value of the second temperature sensor does not reach the predetermined amount of change, the temperature of the wash water in the hot water storage tank 2. The sanitary washing device according to claim 1, wherein the heater is kept off until a preset second temperature lower than the first temperature is reached. In the heat retention control, the control unit turns on the heater to determine whether or not the temperature of wash water in the hot water storage tank has reached the target temperature, and then turns off the heater to turn off the hot water storage tank. 2. The apparatus according to claim 1, wherein when the temperature of the wash water inside reaches the first temperature, the heater is kept off until a change in the measured value of the second temperature sensor reaches a predetermined change. Sanitary cleaning equipment.

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