JP7115153B2 - sanitary washing equipment - Google Patents

Description

The present disclosure relates to sanitary washing devices.

Conventionally, there has been known a sanitary washing device that discharges warm water to the private parts of the human body. This type of sanitary washing device includes a heater for heating water and a temperature sensor for measuring the temperature of the water heated by the heater.

For example, Patent Document 1 discloses a water inlet thermistor provided upstream of a heater, a hot water thermistor provided downstream of a heat exchanger, and a limiter thermistor provided downstream of the hot water thermistor. A sanitary washing device is disclosed. The incoming water thermistor and the hot water thermistor are used for feedback control of the heat exchanger, and the limiter thermistor is used to ensure that the temperature of the water leaving the heat exchanger is safe for the human body.

JP 2015-227773 A

However, in the above-described conventional technology, the temperature sensor may deteriorate over time due to long-term use of the sanitary washing device (for example, 5 to 10 years). When the temperature sensor deteriorates over time, it may become difficult to appropriately control the temperature of the water discharged to the human body.

The present disclosure provides technology capable of detecting an abnormality in a temperature sensor.

A sanitary washing device according to an aspect of the present disclosure includes a heater that heats water, a first temperature sensor that is arranged upstream of the heater and measures the temperature of water flowing into the heater, and A second temperature sensor is arranged on the downstream side and measures the temperature of the water flowing out of the heater. and a control unit that determines an abnormality of the temperature sensor or the second temperature sensor.

Since two temperature sensors placed in different thermal environments deteriorate at different speeds, there is a high possibility that the timing at which temperature drift occurs will be different between the two temperature sensors. Therefore, by comparing the output values of two temperature sensors arranged in different thermal environments, it is possible to determine whether one of these two temperature sensors is abnormal.

Further, the control unit compares the output value of the first temperature sensor and the output value of the second temperature sensor when determining that the first temperature sensor and the second temperature sensor are in a state of thermal equilibrium. .

Abnormalities in the temperature sensors can be accurately determined by comparing the output values of the first temperature sensor and the second temperature sensor when they are in thermal equilibrium.

Further, the control unit determines that the first temperature sensor and the second temperature sensor are in thermal equilibrium when a predetermined time has elapsed after the heater is stopped. Thereby, it is possible to easily determine whether or not the first temperature sensor and the second temperature sensor have reached a thermal equilibrium state.

Further, the control unit controls the first temperature sensor when the rate of change per unit time of the output values of the first temperature sensor and the second temperature sensor is below a threshold value in a state where the heater is stopped. and determine that the second temperature sensor is in thermal equilibrium. Accordingly, it is possible to accurately determine whether or not the first temperature sensor and the second temperature sensor have reached a thermal equilibrium state.

Further, the sanitary washing device according to an aspect of the present disclosure is arranged downstream of a water supply channel through which water flows and on the downstream side of the first temperature sensor and upstream of the second temperature sensor, and the water supply channel is disposed in the atmosphere. and an atmosphere opening portion for opening the water supply passage to the atmosphere, and the control portion controls the output value of the second temperature sensor obtained in a state in which the water supply passage on the downstream side of the atmosphere opening portion is drained by the atmosphere opening portion. A comparison is made with the output value of the first temperature sensor.

Since the inside of the water supply channel on the upstream side of the air release portion is in a closed state, the water in the water supply channel on the upstream side of the air release portion does not evaporate, or if it evaporates, the amount is very small. For this reason, in the water supply channel upstream of the atmospheric release portion, the water temperature drop due to the heat of vaporization can be ignored, and the temperature of the water in the water supply channel upstream of the atmospheric release portion is detected by the second temperature sensor. converges toward the room temperature to be measured. Therefore, the abnormality of the temperature sensor can be determined earlier.

Further, the control unit determines that the first temperature sensor and the second temperature sensor are in thermal equilibrium when the heater is stopped and the water is being supplied. When the heater is stopped and water is being supplied, the temperature of the first temperature sensor arranged upstream of the heater and the temperature of the second temperature sensor arranged downstream of the heater Temperature converges to the temperature of water. Therefore, in this state, the control unit can determine that the first temperature sensor and the second temperature sensor are in thermal equilibrium.

According to the present disclosure, an abnormality of a temperature sensor can be detected.

FIG. 1 is a perspective view schematically showing a toilet apparatus equipped with a sanitary washing device according to an embodiment. FIG. 2 is a diagram showing an example of the configuration of the sanitary washing device according to the embodiment. FIG. 3 is an explanatory diagram of temperature drift. FIG. 4 is a graph showing temperature changes of the water inflow thermistor and the limiter thermistor during the cleaning process. FIG. 5 is an explanatory diagram of execution timings of temperature sensor abnormality determination processing. FIG. 6 is a flowchart illustrating an example of the procedure of abnormality determination processing according to the embodiment. FIG. 7 is a diagram showing an example of the configuration of a sanitary washing device according to a modification.

EMBODIMENT OF THE INVENTION Below, the form (it describes as "embodiment" hereafter) for implementing the sanitary washing apparatus which concerns on this indication is demonstrated in detail, referring drawings. Note that the sanitary washing device according to the present disclosure is not limited to this embodiment. Further, each embodiment can be appropriately combined within a range that does not contradict the processing contents. Also, in each of the following embodiments, the same parts are denoted by the same reference numerals, and overlapping descriptions are omitted.

FIG. 1 is a perspective view schematically showing a toilet apparatus equipped with a sanitary washing device according to an embodiment. In order to make the explanation easier to understand, FIG. 1 shows a three-dimensional orthogonal coordinate system in which the X-axis direction, the Y-axis direction, and the Z-axis direction are defined to be orthogonal to each other, and the Z-axis positive direction is the vertically upward direction. Illustrated. Moreover, in this specification, the expression "water" does not necessarily mean cold water, but may be used to mean hot water.

As shown in FIG. 1, the toilet apparatus 1 includes a western-style toilet bowl (hereinafter referred to as "toilet bowl") 10 and a sanitary washing device 20, and is installed in the toilet room TR. The toilet bowl 10 is of a low tank type that cleans with water stored in a water storage tank 11, but is not limited to this, and may be of a flush valve type, for example. In the example shown in FIG. 1, the floor-mounted toilet bowl 10 is shown, but the present invention is not limited to this, and a wall-mounted toilet bowl or the like may be used.

A sanitary washing device 20 is provided above the toilet bowl 10 . 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 has a case 23 . The case 23 houses nozzles and the like.

FIG. 2 is a diagram showing an example of the configuration of the sanitary washing device according to the embodiment. The sanitary washing device 20 includes a water supply path 30, a valve unit 40, a heat exchanger 50, an electrolytic cell unit 60, a vacuum breaker 70, a switching valve 80, and a nozzle 90. The sanitary washing device 20 also includes an inflow water thermistor 101 , a hot water thermistor 102 and a limiter thermistor 103 . 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 heat exchanger 50, the electrolytic cell unit 60, the vacuum breaker 70, the switching valve 80, the nozzle 90, the incoming water thermistor 101, the hot water thermistor 102, the limiter thermistor 103, the control unit 200, and the storage unit 250 are , are accommodated in the case 23 of the sanitary washing device 20 .

The water supply channel 30 connects a water pipe A, which is an example of a water supply source, to the nozzle 90 and supplies water from the water pipe A to the nozzle 90 .

The water supply passage 30 includes, in order from the upstream side (that is, the water pipe A side), a valve unit 40, an inflow water thermistor 101, a heat exchanger 50, a hot water thermistor 102, an electrolytic cell unit 60, a vacuum breaker 70, a limiter thermistor 103, and a switching valve. 80 is provided.

The valve unit 40 opens and closes the water supply passage 30 according to a control signal from the controller 200 . Heat exchanger 50 is, for example, a momentary heat exchanger. The heat exchanger 50 has a heating element, and heats the water flowing through the water supply path 30 to a set temperature while maintaining its flow velocity.

The electrolyzer unit 60 has an anode plate and a cathode plate inside thereof, and is driven in accordance with a control signal from the control unit 200 to electrolyze the water flowing inside to function the water containing hypochlorous acid. Generates as water.

The vacuum breaker 70 prevents the backflow of water from the nozzle 90 to the heat exchanger 50 and the like by causing the backflowing water to flow to the atmosphere release path (not shown) when negative pressure is generated in the water supply path 30 .

The switching valve 80 is driven according to a control signal from the control unit 200 to switch the outflow destination of the water flowing through the water supply path 30 . For example, the switching valve 80 switches the outflow destination of the water flowing through the water supply path 30 to one of a plurality of outlets provided in the nozzle 90 . Further, the functional water flowing through the water supply channel 30 is switched to the nozzle cleaning channel 85 by the switching valve 80 . The functional water flowing through the nozzle cleaning channel 85 is supplied to the surface of the nozzle 90 . The nozzle 90 is thereby cleaned.

The nozzle 90 discharges water flowing through the water supply channel 30 toward the private parts of the user sitting on the toilet seat. The nozzle 90 is configured to be able to advance and retreat with respect to the case 23 (see FIG. 1). Specifically, the nozzle 90 is connected to a driving source such as a motor (not shown). Moved to and from the stored position. The nozzle 90 discharges water to the private part of the user at the advanced position to wash the private part.

The inflow water thermistor 101 , the hot water thermistor 102 and the limiter thermistor 103 are temperature sensors that measure the temperature of the water flowing through the water supply passage 30 .

The inflow water thermistor 101 is arranged downstream of the valve unit 40 and upstream of the heat exchanger 50 , and detects water before flowing into the heat exchanger 50 , in other words, before being heated by the heat exchanger 50 . to measure the temperature of the water in the The hot water thermistor 102 is arranged downstream of the heat exchanger 50 and upstream of the electrolytic cell unit 60, and is used to remove the water flowing out of the heat exchanger 50, in other words, the water heated by the heat exchanger 50. Measure the temperature.

The limiter thermistor 103 is arranged downstream of the hot water thermistor 102 . Specifically, the limiter thermistor 103 is arranged downstream of the vacuum breaker 70 and upstream of the switching valve 80, and confirms that the temperature of the water discharged from the nozzle 90 is safe for the human body. used for

Output values of the inflow water thermistor 101 , the hot water thermistor 102 and the limiter thermistor 103 are input to the control unit 200 . The output values of the inflow water thermistor 101, the hot water thermistor 102, and the limiter thermistor 103 are expressed, for example, by digital values from 0 to 255 (hereinafter referred to as "AD values"). Control unit 200 converts AD values input from water inflow thermistor 101 and the like into temperatures using a conversion table stored in advance in storage unit 250 .

The control unit 200 is realized by executing a program stored in the storage unit 250 by a CPU (Central Processing Unit), an MPU (Micro Processing Unit), or the like, using the RAM as a work area. Also, the control unit 200 can 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 heat exchanger 50, the electrolytic cell unit 60, the switching valve 80, etc. based on various signals that are input. Storage unit 250 is realized by a semiconductor memory element such as RAM (Random Access Memory), flash memory, or the like.

Based on the output values of the incoming water thermistor 101 and the hot water thermistor 102, the control unit 200 feedback-controls the heat exchanger 50 so that the temperature of the water flowing out of the heat exchanger 50 is within a predetermined range with respect to the set temperature. Specifically, the control unit 200 controls the heat exchanger 50 to perform temperature control processing for increasing or decreasing the amount of heat for heating the water so that the temperature of the water reaches the set temperature.

Also, when the output value of the limiter thermistor 103 is equal to or higher than the threshold, the control unit 200 determines that the temperature of the water flowing out of the heat exchanger 50 exceeds the safe temperature for the human body. In this case, the control unit 200 stops the temperature control process described above so that the water is not heated. Alternatively, the controller 200 may control the valve unit 40 to forcibly stop water discharge when the output value of the limiter thermistor 103 is equal to or greater than the threshold value.

The inflow water thermistor 101, the hot water thermistor 102, and the limiter thermistor 103 may experience a phenomenon called temperature drift due to deterioration over time due to long-term use of the sanitary washing device 20, for example. This point will be described with reference to FIG. FIG. 3 is an explanatory diagram of temperature drift.

As described above, the control unit 200 converts the AD value input from the temperature sensor such as the water inflow thermistor 101 into a temperature using a conversion table stored in advance, thereby determining the water temperature at each point of the water supply passage 30. are aware of For example, as exemplified in FIG. According to the conversion table, it recognizes that the water temperature at the place where the limiter thermistor 103 is arranged is "45°C".

However, when a temperature drift occurs in the limiter thermistor 103, the limiter thermistor 103 outputs the AD value "80" to the control unit 200 even though the actual water temperature is, for example, 50.degree. In this case, the control unit 200 erroneously recognizes that the temperature of the water at the place where the limiter thermistor 103 is arranged is "45°C" even though the actual water temperature is 50°C. As a result, water of 50° C., which is higher than the set temperature of 45° C., is discharged from the nozzle 90 onto the human body.

Thus, the temperature drift is a phenomenon in which the temperature pre-associated with the AD value output from the temperature sensor deviates from the actual temperature. This is a phenomenon, and temperature drift may occur, which may make it difficult to appropriately control the temperature of the water discharged to the human body. Although the case where the AD value of limiter thermistor 103 shifts to the high temperature side has been described here, the AD value of limiter thermistor 103 may shift to the low temperature side due to temperature drift.

On the other hand, among the temperature sensors provided in the sanitary washing device 20, the water inflow thermistor 101 is arranged in the water supply passage 30 upstream of the heat exchanger 50, and the limiter thermistor 103 is arranged in the water supply passage downstream of the heat exchanger 50. 30.

Normal temperature water before being heated by the heat exchanger 50 flows through the water supply path 30 on the upstream side of the heat exchanger 50 . On the other hand, heated water flows through the water supply passage 30 on the downstream side of the heat exchanger 50 when the heat exchanger 50 is operating, and when the heat exchanger 50 is not operating Normal temperature water will flow. That is, the water supply path 30 on the upstream side of the heat exchanger 50 and the water supply path 30 on the downstream side of the heat exchanger 50 have different thermal environments.

Two temperature sensors placed in different thermal environments will degrade at different rates. Specifically, the limiter thermistor 103 arranged on the downstream side of the heat exchanger 50 is more susceptible to thermal shock than the water inflow thermistor 101 arranged on the upstream side of the heat exchanger 50, so the water inflow thermistor 101 expected to deteriorate more rapidly than In other words, it can be said that the limiter thermistor 103 is more susceptible to temperature drift than the water intrusion thermistor 101 .

Therefore, in the sanitary washing device 20 according to the embodiment, by comparing the AD values of two temperature sensors placed under different thermal environments, specifically, the water inflow thermistor 101 and the limiter thermistor 103, an abnormality of the temperature sensor is detected. was determined.

FIG. 4 is a graph showing temperature changes of the water inflow thermistor 101 and the limiter thermistor 103 during the cleaning process. In FIG. 4, the temperature change of the inflow water thermistor 101 is indicated by a dashed line, and the temperature change of the limiter thermistor 103 is indicated by a solid line.

As shown in FIG. 4, for example, at time t1, the control unit 200 starts the washing process when an instruction to spray water from the nozzle 90 to the private parts of the human body is given by operating an operation unit (not shown) or the like. The cleaning process includes a pre-cleaning process, a main cleaning process, and a post-cleaning process.

The pre-cleaning process and the post-cleaning process are processes for cleaning the nozzle 90 . For example, in the pre-washing process and the post-washing process, in order to wash the discharge port of the nozzle 90, water is discharged from the nozzle 90 at a low flow rate so as not to be discharged to the private parts of the human body, and the body of the nozzle 90 is washed. In order to clean the surface of the nozzle 90, body cleaning or the like is performed by discharging water from the outside of the nozzle 90 onto the surface of the body of the nozzle 90. As shown in FIG.

Further, in the main washing process, water is discharged from the discharge port of the nozzle 90 toward the private parts of the human body. This washing process ends, for example, at time t2 when an instruction is given by operating an operation unit (not shown) to end water discharge from the nozzle 90 to the private parts of the human body, and then the post-washing process is started. Note that switching of the water outflow destination is performed by the control unit 200 controlling the switching valve 80 .

The controller 200 opens the valve unit 40 and controls the heat exchanger 50 to start heating water at time t1 when the pre-cleaning process is started. Further, the control unit 200 closes the valve unit 40 to stop the water heating by the heat exchanger 50 at the time t3 when the post-cleaning process ends.

In the standby state before the cleaning process is started, the temperature of the water existing upstream of the heat exchanger 50 and the temperature of the water existing downstream of the heat exchanger 50 are substantially the same. Therefore, the AD value of the inflow water thermistor 101 arranged upstream of the heat exchanger 50 and the AD value of the limiter thermistor 103 arranged downstream of the heat exchanger 50 are almost the same in the standby state. Become.

After that, when the heat exchanger 50 starts to heat the water with the start of the cleaning process, the temperature of the water flowing downstream of the heat exchanger 50 rises. As a result, the AD value of limiter thermistor 103 arranged downstream of heat exchanger 50 increases. On the other hand, since the water flowing upstream of the heat exchanger 50 is not heated, the AD value of the incoming water thermistor 101 arranged upstream of the heat exchanger 50 hardly changes. When the temperature of fresh water is lower than the room temperature of the toilet room TR, the AD value of the water inflow thermistor 101 slightly decreases after the time t1, as shown in FIG. This is because the valve unit 40 is opened at time t1 and new water is supplied from the water pipe A (see FIG. 2), so that the temperature of the water flowing upstream of the heat exchanger 50 drops. be.

After that, when the heating of the water by the heat exchanger 50 is stopped, the temperature of the water flowing downstream of the heat exchanger 50 is gradually lowered by natural cooling. As a result, the AD value of limiter thermistor 103 arranged downstream of heat exchanger 50 decreases. Then, the AD value of the inflow water thermistor 101 arranged on the upstream side of the heat exchanger 50 and the AD value of the limiter thermistor 103 arranged on the downstream side of the heat exchanger 50 again become substantially the same value. . In FIG. 4, the AD value of the water inflow thermistor 101 slightly increases after time t3. , the temperature of the water existing upstream of the heat exchanger 50 converges toward the room temperature of the toilet room TR.

As described above, the limiter thermistor 103 is subjected to a thermal shock every time the cleaning process is performed, so it is considered that it deteriorates more quickly than the water inflow thermistor 101, and temperature drift is likely to occur.

Control unit 200 compares the AD values of water inflow thermistor 101 and limiter thermistor 103 placed under different thermal environments.

Next, the execution timing of the temperature sensor abnormality determination process will be described with reference to FIG. FIG. 5 is an explanatory diagram of execution timings of temperature sensor abnormality determination processing.

The temperature sensor abnormality determination process is executed when it is determined that the inflow water thermistor 101 and the limiter thermistor 103 are in thermal equilibrium. A state of thermal equilibrium is a state in which there is no heat transfer between bodies.

The execution timing of the abnormality determination process, that is, the timing at which the water inflow thermistor 101 and the limiter thermistor 103 are brought into a state of thermal equilibrium is, for example, during standby (S11) or when the standby time reaches a predetermined time, as shown in FIG. during execution of the nozzle cleaning process (S12).

During standby (S11), water is not heated by the heat exchanger 50, so the temperature of the water supply channel 30 on the upstream side and the water supply channel 30 on the downstream side of the heat exchanger 50 is the same as the room temperature of the toilet room TR. converges to Along with this, the temperatures of the water inflow thermistor 101 and the limiter thermistor 103 also converge to the room temperature and enter a thermal equilibrium state. In this way, during standby, the temperature of the water inflow thermistor 101 and the temperature of the limiter thermistor 103 are the same. By comparing the AD values of the water inflow thermistor 101 and the limiter thermistor 103 at this time, it is possible to determine whether the water inflow thermistor 101 or the limiter thermistor 103 is abnormal when there is a difference between the two.

Here, the vacuum breaker 70 opens the water supply channel 30 to the atmosphere when the water supply to the water supply channel 30 is stopped, so that the water accumulated in the water supply channel 30 on the downstream side of the vacuum breaker 70 is discharged to the nozzle. It has a draining mechanism for draining from 90 . Since the limiter thermistor 103 is arranged in the water supply passage 30 on the downstream side of the vacuum breaker 70, it measures the temperature of the gas in the water supply passage 30 after the time t3 has elapsed, that is, in the standby state. As described above, the temperature of the water existing in the water supply passage 30 on the upstream side of the vacuum breaker 70 converges to the room temperature of the toilet room TR. will converge to approximately the same value.

In this way, when the abnormality determination process is performed at the timing of the standby state (S11), the AD value of the limiter thermistor 103 obtained when the water supply passage 30 on the downstream side of the vacuum breaker 70 is drained is used. comparison will be made.

Since the inside of the water supply passage 30 on the upstream side of the vacuum breaker 70 is in a closed state, the water in the water supply passage 30 on the upstream side of the vacuum breaker 70 does not evaporate, or if it evaporates, the amount is very small. . Therefore, in the water supply passage 30 on the upstream side of the vacuum breaker 70, the water temperature drop due to the heat of vaporization can be ignored, and the temperature of the water in the water supply passage 30 on the upstream side of the vacuum breaker 70 is controlled by the limiter thermistor. It converges toward the room temperature of the toilet room TR measured by 103 . Therefore, the abnormality of the temperature sensor can be determined earlier.

Also during the nozzle cleaning process (step S12), the temperature of the water inflow thermistor 101 and the temperature of the limiter thermistor 103 are the same.

Specifically, in the nozzle cleaning process, the control unit 200 opens the valve unit 40 and controls the electrolytic cell unit 60 to generate functional water, and the generated functional water is discharged from the nozzle cleaning channel 85 to the nozzle. Feed 90 surfaces.

As described above, in the nozzle cleaning process, the water is passed through the water supply passage 30 without heating the water by the heat exchanger 50. Both the temperature and the temperature of the limiter thermistor 103 converge to the temperature of the water flowing through the water supply passage 30 . By comparing the AD values of the water inflow thermistor 101 and the limiter thermistor 103 at this time, it is possible to determine whether the water inflow thermistor 101 or the limiter thermistor 103 is abnormal when there is a difference between the two.

It should be noted that the nozzle cleaning process is performed every time the standby time, that is, the non-use time reaches a certain period of time (for example, 8 hours). In addition, the nozzle cleaning process may be executed after a certain period of time (for example, 25 seconds) has elapsed after the seating sensor or the like detects that the user has left the seat after the cleaning process. Further, the control unit 200 may pass water without heating by the heat exchanger 50 in order to perform the abnormality determination process of the temperature sensor, not limited to during the nozzle cleaning process (S12). Further, the control unit 200 may execute the abnormality determination process before starting the water heating by the heat exchanger 50 when the start of the cleaning process is instructed by operating the operation unit (not shown) or the like. .

Thus, by comparing the AD values of both temperature sensors when the water inflow thermistor 101 and the limiter thermistor 103 are in thermal equilibrium, it is possible to accurately determine whether the temperature sensors are abnormal.

Next, the procedure of temperature sensor abnormality determination processing will be described with reference to FIG. FIG. 6 is a flowchart illustrating an example of the procedure of abnormality determination processing according to the embodiment.

As shown in FIG. 6, the control unit 200 determines whether or not the water inflow thermistor 101 and the limiter thermistor 103 have reached a thermal equilibrium state (step S101).

For example, after the heat exchanger 50 stops heating water at time t3 shown in FIG. can be determined to have been achieved. The above-mentioned predetermined time is a sufficient time for the inflow water thermistor 101 and the limiter thermistor 103 to reach a state of thermal equilibrium, and is determined by experiments or the like.

By acquiring in advance the time required for the water inflow thermistor 101 and the limiter thermistor 103 to reach thermal equilibrium, it is possible to easily determine whether the water inflow thermistor 101 and the limiter thermistor 103 have reached a state of thermal equilibrium. be able to. The time required for the inflow water thermistor 101 and the limiter thermistor 103 to reach thermal equilibrium is, for example, 40 minutes.

Note that if the cleaning process is restarted before the predetermined time elapses, the control unit 200 controls the water inflow thermistor 101 and the limiter thermistor 103 even if the predetermined time elapses. may not be determined to have reached thermal equilibrium. In this case, the control unit 200 causes the water inflow thermistor 101 and the limiter thermistor 103 to be in a state of thermal equilibrium when a predetermined time has elapsed after the water heating by the heat exchanger 50 is stopped in the restarted cleaning process. determined to have reached

Further, control unit 200 may monitor changes in the AD values of inflow water thermistor 101 and limiter thermistor 103 after water heating by heat exchanger 50 is stopped at time t3. In this case, the control unit 200 can determine whether or not the inflow water thermistor 101 and the limiter thermistor 103 have reached a state of thermal equilibrium based on this monitoring result. That is, control unit 200 controls water inflow thermistor 101 and limiter thermistor 103 when the rate of change per unit time of the AD values of water inflow thermistor 101 and limiter thermistor 103 falls below the threshold value, that is, when the change in the AD value converges. determines that has reached thermal equilibrium. The rate of change per unit time is, for example, the amount of change of 0.5° C. in 10 minutes.

By monitoring changes in the AD values of water inflow thermistor 101 and limiter thermistor 103 in this manner, it is possible to accurately determine whether or not water inflow thermistor 101 and limiter thermistor 103 have reached thermal equilibrium.

Note that if the cleaning process is restarted before the changes in the AD values of the water inflow thermistor 101 and the limiter thermistor 103 converge, the control unit 200 temporarily adjusts the water inflow thermistor 101 and the limiter thermistor 103 in the restarted cleaning process. Even if the change in the AD value of 103 converges, it is not determined that the inflow water thermistor 101 and the limiter thermistor 103 have reached a thermal equilibrium state. That is, even if the AD value of the limiter thermistor 103 converges to the AD value corresponding to the set temperature of the heat exchanger 50 in the restarted cleaning process, it is determined that the water inflow thermistor 101 and the limiter thermistor 103 have reached a thermal equilibrium state. do not do.

Control unit 200 repeats the process of step S101 until water inflow thermistor 101 and limiter thermistor 103 reach a thermal equilibrium state.

On the other hand, when it is determined in step S101 that the water inflow thermistor 101 and the limiter thermistor 103 have reached a thermal equilibrium state (step S101, Yes), the control unit 200 acquires the AD value V1 of the water inflow thermistor 101 (step S102). , the AD value V2 of the limiter thermistor 103 is obtained (step S103).

Subsequently, the control unit 200 determines whether or not the absolute value of the difference between the AD value V1 and the AD value V2 is within the threshold (step S104). In this process, when it is determined that the absolute value of the difference between the AD value V1 and the AD value V2 is within the threshold value (step S104, Yes), the control unit 200 determines that the water inflow thermistor 101 and the limiter thermistor 103 are normal. (Step S105), and terminates the abnormality determination process. Note that the control unit 200 may return the process to step S101.

On the other hand, when the absolute value of the difference between the AD value V1 and the AD value V2 exceeds the threshold value in step S104 (step S104, No), the control unit 200 determines that either the water inflow thermistor 101 or the limiter thermistor 103 is abnormal. (Step S106), the abnormality handling process is performed (Step S107), and the process is terminated.

For example, as the abnormality handling process, the control unit 200 turns on an LED (Light Emitting Diode) indicator provided in the main unit 21 of the sanitary washing device 20 or an operation unit (not shown) to indicate that an abnormality has occurred in the limiter thermistor 103. The user may be notified of this. Further, the control unit 200 may prohibit the temperature control process by the heat exchanger 50 as the abnormality handling process so that water having a temperature exceeding the set temperature is not discharged to the human body.

Here, it is determined that either the water inflow thermistor 101 or the limiter thermistor 103 is abnormal. It may be determined that

As described above, the sanitary washing device 20 according to the embodiment compares the AD values of the water inflow thermistor 101 and the limiter thermistor 103, which are two temperature sensors arranged in different thermal environments, to determine whether the temperature sensor is abnormal. It was decided to.

Since two temperature sensors placed in different thermal environments deteriorate at different speeds, there is a high possibility that the timing at which temperature drift occurs will be different between the two temperature sensors. Therefore, by comparing the AD values of two temperature sensors placed in different thermal environments, it is possible to determine whether one of these two temperature sensors is abnormal.

In addition, in the sanitary washing device 20 according to the embodiment, since the AD values of both the temperature sensors are compared when the water inflow thermistor 101 and the limiter thermistor 103 are in a state of thermal equilibrium, it is possible to accurately determine the abnormality of the temperature sensors. can.

In addition, in Japanese Patent Application Laid-Open No. 07-333074, in a fire alarm that incorporates a temperature detection element for detecting a fire and a test element for testing the function of the temperature detection element, the output value of the temperature detection element and the output value of the test element to detect an abnormality in the temperature sensing element. However, Japanese Patent Laying-Open No. 07-333074 assumes that the temperature sensing element and the test element are placed in the same thermal environment, and does not describe placing them in different thermal environments.

(Modification)
In the above-described embodiment, a so-called instant-type sanitary washing device without a hot water storage tank has been described as an example, but the present invention is not limited to this, and a so-called hot water storage type sanitary washing device with a hot water storage tank may be used. Here, a configuration example of a hot water storage type sanitary washing device will be described with reference to FIG. FIG. 7 is a diagram showing an example of the configuration of a sanitary washing device according to a modification.

As shown in FIG. 7, the sanitary washing device 20A according to the modification includes a hot water storage tank 55 that stores water flowing through the water supply path 30 instead of the heat exchanger 50 (see FIG. 2). The hot water storage tank 55 is arranged downstream of the inflow thermistor 101 and upstream of the electrolytic cell unit 60 . A heater 56 and a hot water thermistor 102 are arranged inside the hot water storage tank 55 . Heater 56 heats the water stored in hot water storage tank 55 under the control of control unit 200 .

The control unit 200 of the sanitary washing device 20A can, for example, perform temperature sensor abnormality determination processing during standby (S11) shown in FIG. 5, as in the above-described embodiment.

Further, in the above-described embodiment, by comparing the AD values of water inflow thermistor 101 and limiter thermistor 103, abnormality of water inflow thermistor 101 or limiter thermistor 103 is determined. Alternatively, the control unit 200 may determine whether the inlet water thermistor 101 or the hot water thermistor 102 is abnormal by comparing the AD values of the inlet water thermistor 101 and the hot water thermistor 102 .

As described above, the sanitary washing devices 20 and 20A according to the embodiments include a heater (for example, the heat exchanger 50 and the heater 56) that heats water, and a heater that is arranged upstream of the heater, and the water flows into the heater. A first temperature sensor (inlet water thermistor 101 as an example) that measures the temperature of water, and a second temperature sensor (a hot water thermistor 102 as an example) that is arranged downstream of the heater and measures the temperature of water flowing out of the heater. , limiter thermistor 103), and a control unit 200 for determining abnormality of the first temperature sensor or the second temperature sensor by comparing the output value of the first temperature sensor and the output value of the second temperature sensor. By comparing the output values of two temperature sensors placed in different thermal environments in this way, it is possible to determine whether one of these two temperature sensors is abnormal.

Further, when the control unit 200 determines that the first temperature sensor and the second temperature sensor are in thermal equilibrium, the control unit 200 compares the output value of the first temperature sensor and the output value of the second temperature sensor. Thus, by comparing the output values of the first temperature sensor and the second temperature sensor when they are in thermal equilibrium, it is possible to accurately determine whether the temperature sensors are abnormal.

Further, the control unit 200 determines that the first temperature sensor and the second temperature sensor are in a state of thermal equilibrium when a predetermined time has passed after the heater is stopped. Thereby, it is possible to easily determine whether or not the first temperature sensor and the second temperature sensor have reached a thermal equilibrium state.

In addition, when the rate of change per unit time of the output values of the first temperature sensor and the second temperature sensor is below the threshold while the heater is stopped, the control unit 200 controls the first temperature sensor and the second temperature sensor. Determine that the sensor is in thermal equilibrium. Thereby, it is possible to accurately determine whether or not the first temperature sensor and the second temperature sensor have reached a thermal equilibrium state.

The sanitary washing devices 20 and 20A also include a water supply passage 30 through which water flows, and an atmosphere release portion arranged downstream of the first temperature sensor and upstream of the second temperature sensor to open the water supply passage 30 to the atmosphere. (for example, a vacuum breaker 70), and the control unit 200 detects the output value of the second temperature sensor obtained in a state where the water supply passage 30 on the downstream side of the air release unit is drained by the air release unit. Compare with the output value of the first temperature sensor.

Since the inside of the water supply passage 30 on the upstream side of the air opening portion is in a sealed state, the water in the water supply passage 30 on the upstream side of the air opening portion does not evaporate, or if it evaporates, the amount is small. . Therefore, in the water supply passage 30 on the upstream side of the open-to-atmosphere portion, the water temperature drop due to the heat of vaporization can be ignored, and the temperature of the water in the water supply passage 30 on the upstream side of the open-to-atmosphere portion is the second It converges toward the room temperature measured by the temperature sensor. Therefore, the abnormality of the temperature sensor can be determined earlier.

Further, the control unit 200 determines that the first temperature sensor and the second temperature sensor are in a state of thermal equilibrium when the heater is stopped and the water is flowing. When the heater is stopped and water is being supplied, the temperature of the first temperature sensor arranged upstream of the heater and the temperature of the second temperature sensor arranged downstream of the heater Temperature converges to the temperature of water. Therefore, in this state, the control unit can determine that the first temperature sensor and the second temperature sensor are in thermal equilibrium.

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.

A Water pipe TR Toilet room 1 Toilet device 10 Toilet bowl 20 Sanitary washing device 30 Water supply path 40 Valve unit 50 Heat exchanger 60 Electrolyzer unit 70 Vacuum breaker 80 Switching valve 85 Nozzle cleaning flow path 90 Nozzle 101 Inlet water thermistor 102 Hot water thermistor 103 Limiter thermistor 200 Control unit 250 Storage unit

Claims (6)

a heater for heating water;
a first temperature sensor arranged upstream of the heater and measuring the temperature of water flowing into the heater;
a second temperature sensor arranged downstream of the heater and measuring the temperature of water flowing out of the heater;
A sanitary washing apparatus comprising: a control unit that determines an abnormality of the first temperature sensor or the second temperature sensor by comparing an output value of the first temperature sensor and an output value of the second temperature sensor. The control unit
The output value of the first temperature sensor and the output value of the second temperature sensor are compared when it is determined that the first temperature sensor and the second temperature sensor are in thermal equilibrium. Sanitary cleaning equipment. The control unit
3. The sanitary washing apparatus according to claim 2, wherein the output value of said first temperature sensor and the output value of said second temperature sensor are compared when a predetermined time has elapsed after said heater is stopped. The control unit
When the rate of change per unit time of the output values of the first temperature sensor and the second temperature sensor is below a threshold while the heater is stopped, the first temperature sensor and the second temperature sensor 3. A sanitary washing device according to claim 2, wherein the sanitary washing device is determined to be in thermal equilibrium. a water supply channel through which water flows;
an atmosphere opening portion arranged downstream of the first temperature sensor and upstream of the second temperature sensor, and opening the water supply passage to the atmosphere;
The control unit
The output value of the second temperature sensor obtained in a state in which the water supply passage on the downstream side of the atmosphere release portion is drained by the atmosphere release portion is compared with the output value of the first temperature sensor. The sanitary washing device according to any one of 1 to 4. The control unit
3. The sanitary washing device according to claim 2, wherein said first temperature sensor and said second temperature sensor are determined to be in thermal equilibrium when said heater is stopped and water is being supplied. .

Images