JP6657578B2 - Water leak detection device - Google Patents

Description

  Embodiments of the present invention relate to a water leak detection device.

  2. Description of the Related Art Conventionally, there has been known a technology for detecting water leakage in a hot water appliance that discharges water from a discharge port by heating water supplied from a water supply port. In such a conventional hot water device, one temperature sensor is often provided on each of the water supply port side and the discharge port side.

JP 2009-114463 A

  In the prior art, it was necessary to provide a dedicated configuration for detecting water leakage separately from the temperature sensor, such as providing one water pressure sensor on each of the water supply port side and the discharge port side to detect water leakage. .

The water leakage detection device according to the embodiment is a valve that opens and closes a water flow path from a water supply port to a water discharge port, a heater provided on the flow path, and a second sensor that detects a temperature in the flow path on the water supply port side with respect to the heater. 1 temperature sensor, 2nd temperature sensor which detects the temperature in the flow path on the water outlet side with respect to the heater, and a valve is configured to be controllable. And a control unit that causes the valve to close the flow path when the occurrence of water leakage is detected , and the control unit starts the water discharge operation by causing the valve to open the flow path. Then, detection of water leakage is started . Thus, for example, the water leak can be detected with a simple structure in response to the start of the water discharge operation using two temperature sensors without separately providing a dedicated structure for detecting the water leak.

Further , the water leakage detection device according to the embodiment detects a valve that opens and closes a water flow path from a water supply port to a water discharge port, a heater provided on the flow path, and a temperature in the flow path on the water supply port side with respect to the heater. A first temperature sensor, a second temperature sensor for detecting the temperature in the flow path on the water outlet side with respect to the heater, and a controllable valve, and the detection results of the first temperature sensor and the second temperature sensor A control unit that detects the presence or absence of water leakage on the flow path based on the difference between the two, and causes the valve to close the flow path when the occurrence of water leakage is detected. , A first difference of the detection result when the heater output value is set to the first value, and a second difference of the detection result when the heater output value is set to the second value different from the first value. If the difference from the difference is greater than the threshold value, the To close the road. Thus, for example, water leakage can be detected with a simple configuration using two temperature sensors without separately providing a dedicated configuration for detecting water leakage. Further, for example, it is possible to accurately detect water leakage using the detection results of at least two times.

  In the water leakage detection device according to the embodiment, the control unit may set the heater output value to the second value when the degree of heating by the heater is smaller than setting the heater output value to the first value. After setting to the second value and calculating the second difference, the output value of the heater is set to the first value to calculate the first difference. Thus, for example, by changing the output value of the heater from a small heating degree to a large heating degree, it is possible to easily detect the temperature in the flow channel before and after the change.

  In the water leakage detection device according to the embodiment, the control unit calculates a first value based on a difference between a target temperature and a detection result of the first temperature sensor, and calculates a first value based on the calculated first value. The value of 2 is calculated. Thereby, for example, the first value and the second value can be easily calculated.

  Further, the water leakage detection device according to the embodiment further includes a notification unit that notifies that a water leak has occurred, and the control unit is configured to be able to control the notification unit, and has detected the occurrence of the water leakage based on a difference between the detection results. In this case, the notification unit is notified that water leakage has occurred. Thereby, for example, it is possible to easily notify that the water leakage has occurred.

FIG. 1 is an exemplary block diagram illustrating a schematic configuration of a water leakage detection device according to an embodiment. FIG. 2 is an exemplary flowchart illustrating a process executed by a control unit of the water leakage detection device according to the embodiment.

  Hereinafter, embodiments will be described with reference to the drawings.

  First, a schematic configuration of a water leakage detection device 100 according to an embodiment will be described with reference to FIG. The water leakage detection device 100 is applied to a hot water device such as a human body local cleaning device installed in a toilet.

  As shown in FIG. 1, the water leakage detection device 100 includes an electromagnetic valve 1, a heater 2, an input-side temperature sensor 3, an output-side temperature sensor 4, a flow sensor 5, a control unit 6, a water discharge switch 7, , A notification unit 8. The input-side temperature sensor 3 is an example of a “first temperature sensor”, and the output-side temperature sensor 4 is an example of a “second temperature sensor”.

  The electromagnetic valve 1 is connected to a valve drive unit (not shown) such as a motor, and is configured to open and close a water flow path C (see a dotted line in FIG. 1) from the water supply port P1 to the water discharge port P2. . The heater 2 is provided on the flow path C between the water supply port P1 and the water discharge port P2.

  The input-side temperature sensor 3 is provided on the flow path C between the water supply port P1 and the heater 2 and is configured to detect the temperature in the flow path C on the water supply port P1 side with respect to the heater 2. . The output-side temperature sensor 4 is provided on the flow path C between the heater 2 and the water discharge port P2, and is configured to detect the temperature in the flow path C on the water discharge port P2 side with respect to the heater 2. ing. These two temperature sensors are often provided as a normal configuration in the hot water equipment.

  The flow rate sensor 5 is provided on the flow path C between the heater 2 and the input-side temperature sensor 3, and is configured to detect the flow rate of water flowing through the flow path C.

  The control unit 6 is configured to control each unit of the water leakage detection device 100. For example, the control unit 6 is configured to be able to control the output value of the heater 2 based on the detection results of various sensors (the input-side temperature sensor 3, the output-side temperature sensor 4, and the flow rate sensor 5). ing. The output value of the heater 2 is, for example, a value (duty ratio) of a control signal output to the heater 2. The control unit 6 outputs a control signal to a valve driving unit (not shown) connected to the electromagnetic valve 1 so that the electromagnetic valve 1 can perform control to open and close the flow path C. It is configured.

  The water discharge switch 7 is configured to output a command to switch on / off of the water discharge operation (that is, opening and closing of the flow path C by the solenoid valve 1) to the control unit 6. The water discharge switch 7 can be operated by a user or the like.

  Here, when water leaks on the flow path C, the amount of water reaching the discharge port P2 is reduced, so that the temperature in the flow path C on the water supply port P1 side with respect to the heater 2 and the temperature of the heater 2 On the other hand, the temperature difference from the temperature in the flow path C on the discharge port P2 side tends to increase. Therefore, when water leakage occurs on the flow path C, the difference (difference or ratio) between the temperature T1 detected by the input-side temperature sensor 3 and the temperature T2 detected by the output-side temperature sensor 4 is equal to the water leakage. Tends to be larger than in the case where no occurrence occurs.

  Therefore, the control unit 6 according to the embodiment calculates the difference between the detection results of the input-side temperature sensor 3 and the output-side temperature sensor 4, and detects the presence or absence of water leakage on the flow path C based on the calculation result. It is configured. The control unit 6 is configured to cause the solenoid valve 1 to close the flow path C when detecting the occurrence of water leakage. In the following, an example will be described in which a difference between the temperature T1 detected by the input-side temperature sensor 3 and the temperature T2 detected by the output-side temperature sensor 4 is used as the difference between the detection results. May be used as the difference between the two.

  When the water discharge operation is started, the control unit 6 according to the embodiment changes the duty ratio output to the heater 2 in two stages, and calculates the difference between the measurement results of the input-side temperature sensor 3 and the output-side temperature sensor 4 in each stage. Is configured to detect the presence or absence of water leakage based on More specifically, the control unit 6 sets the first difference ΔT1 of the detection result when the duty ratio is set to the first value D1 and the second value D2 different from the first value D1 to the duty ratio. Is compared with the second difference ΔT2 of the detection result in the case of setting to, and when the difference between the two is larger than a predetermined threshold value ΔTx, it is determined that water leakage has occurred and the flow path C is closed in the solenoid valve 1. It is configured to be.

  In the embodiment, the degree of heating by the heater 2 is smaller when the duty ratio is set to the second value D2 than when the duty ratio is set to the first value D1. The control unit 6 sets the duty ratio to the second value D2 to calculate the second difference ΔT2, and then sets the duty ratio to the first value D1 to calculate the first difference ΔT1. Have been.

  Here, a method of calculating the first value D1 and the second value D2 will be described using equations.

  The first value D1 is calculated based on the difference between the target temperature T0 and the temperature T1 detected by the input-side temperature sensor 3 when water at the temperature T0 is to be discharged from the discharge port P2 ( Equation (1) below).

  D1 = (T0−T1) × A (1)

  In the above equation (1), A is a predetermined coefficient.

  Further, the second value D2 is calculated based on the first value D1 (see the following equation (2)).

  D2 = D1−Δd (2)

  In the above equation (2), Δd is a predetermined constant. Here, in the embodiment, as described above, the second value D2 is smaller than the first value D1 by Δd. However, in the embodiment, there is almost no difference in the temperature of the water discharged from the discharge port P2 between the case where the duty ratio is set to the second value D2 and the case where the duty ratio is set to the first value D1. Thus, Δd is set. That is, in the embodiment, even when the duty ratio is changed between the second value D2 and the first value D1, Δd is set so that the user is less likely to notice a change in the temperature of the water discharged from the discharge port P2. Is done.

  As described above, in the embodiment, in order to calculate the second value D2, it is necessary to calculate the first value D1. In addition, as described above, the control unit 6 according to the embodiment sets the duty ratio to the second value D2 as the first stage of the process of changing the duty ratio in two stages, and then sets the duty ratio to the second stage. , The duty ratio is set to a first value D1.

  The control unit 6 according to the embodiment is configured to calculate the first value D1 twice in the first and second stages of the process of changing the duty ratio in two stages. Thus, for example, unlike the case where the first value D1 calculated for calculating the second value D2 in the first stage is continuously used in the second stage, the first value D1 is calculated based on the latest detection result of the input-side temperature sensor 3. An appropriate first value D1 can be calculated.

  The control unit 6 according to the embodiment is configured to, when detecting the occurrence of water leakage by the above-described control, notify the notification unit 8 that water leakage has occurred. The notification unit 8 is configured to output a warning using a sound or the like to notify that water leakage has occurred.

  Next, a process executed by the control unit 6 of the water leakage detection device 100 according to the embodiment will be described with reference to FIG. The process flow of FIG. 2 is started, for example, when a command to start a water discharging operation is output to the control unit 6 via the water discharging switch 7.

  In S1, the control unit 6 causes the solenoid valve 1 to open the flow path C and starts the water discharging operation.

  In S2, the control unit 6 calculates a first value D1 based on a difference between the target temperature T0 and the temperature T1 detected by the input-side temperature sensor 3 (see the above equation (1)). .

  In S3, the control unit 6 calculates a second value based on the first value D1 calculated in S2 (see the above equation (2)), and outputs the calculated second value D2 to the heater 2. .

  In S4, the control unit 6 calculates a second difference ΔT2 of the detection result between the input-side temperature sensor 3 and the output-side temperature sensor 4 in a state where the processing of S3 is executed, and calculates the calculated second difference ΔT2. Is stored.

  In S5, the control unit 6 calculates the first value D1 again based on the difference between the target temperature T0 and the temperature T1 detected by the input-side temperature sensor 3 (see the above equation (1)). ).

  In S6, the control section 6 outputs the first value D1 calculated in S5 to the heater 2.

  In S7, the control unit 6 calculates a first difference ΔT1 of the detection result of the input-side temperature sensor 3 and the output-side temperature sensor 4 in a state where the processing of S6 is executed, and calculates the calculated first difference ΔT1. Is stored.

  In S8, the controller 6 determines whether the difference between the first difference ΔT1 calculated in S7 and the second difference ΔT2 calculated in S4 is larger than a threshold value ΔTx.

  If it is determined in S8 that the difference between the first difference ΔT1 and the second difference ΔT2 is equal to or smaller than the threshold value ΔTx, the process proceeds to S9. In this case, since it is estimated that no water leakage has occurred on the flow path C, the control unit 6 continues the water discharging operation in S9. Then, the process ends.

  On the other hand, if it is determined in S8 that the difference between the first difference ΔT1 and the second difference ΔT2 is larger than the threshold value ΔTx, the process proceeds to S10. In this case, since it is estimated that water leakage has occurred on the flow path C, the control unit 6 stops the output of the heater 2 and causes the solenoid valve 1 to close the flow path C to perform the water discharging operation in S10. Stop. Then, in S11, the control unit 6 causes the notification unit 8 to output an alarm indicating that water leakage has occurred. Then, the process ends.

  As described above, the control unit 6 according to the embodiment includes the input-side temperature sensor 3 that detects the temperature in the flow path C on the water supply port P1 side with respect to the heater 2 and the water-discharge port P2 side with respect to the heater 2. The presence or absence of water leakage in the flow path C is detected based on the difference between the detection result with the output side temperature sensor 4 that detects the temperature in the flow path C. Is configured to be closed. Thereby, for example, without separately providing a dedicated configuration for detecting water leakage, it is possible to detect water leakage with a simple configuration using two temperature sensors that are often provided as a normal configuration in a hot water device. Can be.

  Further, the control unit 6 according to the embodiment sets the first difference ΔT1 of the detection result when the output value of the heater 2 is set to the first value D1, and sets the output value of the heater 2 to the second value D2. When the difference between the detection result and the second difference ΔT2 is greater than the threshold value ΔTx, it is determined that water leakage has occurred, and the electromagnetic valve 1 is configured to close the flow path C. Thereby, for example, water leakage can be detected with high accuracy using at least two detection results.

  Further, the control unit 6 according to the embodiment sets the output value of the heater 2 to the first value D1 after setting the output value of the heater 2 to the second value D2 and calculating the second difference ΔT2. It is configured to calculate a first difference ΔT1. In the embodiment, the degree of heating by the heater 2 is smaller when the output value of the heater 2 is set to the second value D2 than when the output value of the heater 2 is set to the first value D1. Thus, for example, by changing the output value of the heater 2 from a small heating degree to a large heating degree, it is possible to easily detect the temperature in the flow path C before and after the change.

  The control unit 6 according to the embodiment calculates the first value D1 based on the difference between the target temperature T0 and the detection result (temperature T1) of the input-side temperature sensor 3, and calculates the calculated first value D1. The second value D2 is calculated based on Thereby, for example, first value D1 and second value D2 can be easily calculated.

  Further, the control unit 6 according to the embodiment notifies the notification unit 8 that the water leakage has occurred when detecting the occurrence of the water leakage based on the difference between the detection results of the input-side temperature sensor 3 and the output-side temperature sensor 4. It is configured to be. Thereby, for example, it is possible to easily notify that the water leakage has occurred.

(Modification)
In the above-described embodiment, the configuration has been described in which the output value of the heater is changed in two stages, and water leakage is detected based on the detection result in each stage. However, as a modification, a configuration in which the output value of the heater is not changed is described. Is also conceivable. That is, the difference between the detection results of the two temperature sensors may be calculated only once, and the one-time calculation result may be compared with an appropriate threshold value to detect water leakage. Further, as another modified example, a configuration in which the output value of the heater is changed in three or more stages and water leakage is detected based on the detection result in each stage is also conceivable.

  As described above, the embodiments and the modifications of the present invention have been described. However, the above-described embodiments and the modifications are merely examples, and are not intended to limit the scope of the invention. The above-described embodiments and modifications can be implemented in various forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. The above embodiments and modified examples are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

1 solenoid valve (valve)
2 Heater 3 Input side temperature sensor (first temperature sensor)
4. Output side temperature sensor (second temperature sensor)
6 control unit 8 notification unit 100 water leak detection device C flow path P1 water supply port P2 water discharge port

Claims (5)

A valve for opening and closing the water flow path from the water supply port to the water discharge port,
A heater provided on the flow path;
A first temperature sensor that detects a temperature in the flow path on the water supply port side with respect to the heater;
A second temperature sensor for detecting a temperature in the flow path on the water outlet side with respect to the heater;
The valve is configured to be controllable, based on a difference between detection results of the first temperature sensor and the second temperature sensor, to detect the presence or absence of water leakage on the flow path, and to detect the occurrence of water leakage when the valve is detected. And a control unit for closing the flow path ,
The water leakage detection device , wherein the control unit starts detecting the presence or absence of the water leakage when the valve causes the valve to open the flow path and starts the water discharging operation . A valve for opening and closing the water flow path from the water supply port to the water discharge port,
A heater provided on the flow path;
A first temperature sensor that detects a temperature in the flow path on the water supply port side with respect to the heater;
A second temperature sensor for detecting a temperature in the flow path on the water outlet side with respect to the heater;
The valve is configured to be controllable, based on a difference between detection results of the first temperature sensor and the second temperature sensor, to detect the presence or absence of water leakage on the flow path, and to detect the occurrence of water leakage when the valve is detected. And a control unit for closing the flow path,
The control unit is configured to control an output value of the heater, and sets a first difference of the detection result when the output value of the heater is set to a first value and an output value of the heater to the first value. When the difference from the second difference of the detection result when the second value is set to a value different from the value of 1 is larger than a threshold value, it is determined that water has leaked, to close, water leak detection equipment.   The control unit may set the output value of the heater to the second value if the degree of heating by the heater is smaller when setting the output value of the heater to the second value than when setting the output value to the first value. 3. The water leakage detection device according to claim 2, wherein after setting the value to calculate the second difference, setting the output value of the heater to the first value and calculating the first difference. 4.   The control unit calculates the first value based on a difference between a target temperature and a detection result of the first temperature sensor, and calculates the second value based on the calculated first value. The water leakage detection device according to claim 3, wherein It further includes a notification unit that reports that water leakage has occurred,
5. The control unit according to claim 1, wherein the control unit is configured to be capable of controlling the notification unit, and when the occurrence of water leakage is detected based on a difference between the detection results, notifies the notification unit of the occurrence of water leakage. The water leak detection device according to any one of the preceding claims.

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