JP2008170020A - Electric water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric water heater capable of detecting water leakage found in flowing to a water supply port without affected by water immersion irrespective to water leakage. <P>SOLUTION: This electric water heater 10 comprises a water storage tank 13 for heatably storing the fluid taken through an intake channel 16 and supplying the fluid from the water supply port of a water supply passage 17, a cutoff valve 20 capable of connecting and disconnecting the intake channel 16, a flow sensor 22 capable of detecting the flow of fluid in the intake channel 16, and a control part 15 for operating the cutoff valve 20 on the basis of the detection information. The control part 15 has a time setting means 25 capable of optionally setting a length of a water leakage judgement time T1 as criterion for judgement of water leakage, a water leakage judging means 26 judging the water leakage when a duration time Tc in receiving of the detection information from the flow sensor 22 is over the water leakage judgement time T1, and a cutoff valve operating means 27 for operating the cutoff valve 20 to switch from an opening state to a closing state when the water leakage judging means 26 judges the water leakage. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electric water heater having a function of detecting leakage.

  A conventional electric water heater stores a fluid taken in via a water intake channel, and a heater is provided in a water storage tank that can supply the stored fluid from the water supply channel. There is one in which hot water can be supplied from a water supply port at the tip of the road (see, for example, Patent Document 1).

  As shown in FIG. 4, a water storage tank 54 to which a water intake channel 52 and a water supply channel 53 are connected is accommodated inside the main body case 51, and the water intake channel 52 inside the main body case 51 contains There is an electric water heater 50 provided with a shut-off valve 55, a pressure reducing valve 56, and a flow sensor 57. In the electric water heater 50, the fluid heated by the heater 58 in the water storage tank 54 can be used by the user through the water supply port 59 of the water supply channel 53, and the instantaneous flow rate of the used fluid and the daily use of the fluid are used. The amount of hot water or the like is calculated based on detection information from the flow sensor 57.

  Further, in the electric water heater 50, a drain port 60 is formed at the lower end of the main body case 51, and a pair of terminals 61 are provided in the drain port 60. The pair of terminals 61 are electrically connected to the control unit 62. The control unit 62 determines that water leakage has occurred when the terminals 61 are in the conductive state, and notifies the electrically connected alarm device 63 that the water leakage has occurred, and also sets the shut-off valve 55. It is set as the structure which makes it operate | move and interrupts the intake channel 52. FIG.

In this electric water heater 50, when water leaks in the water intake passage 52, the water storage tank 54, the water supply passage 53, etc., inside the main body case 51, the leaked fluid is discharged from the main body case 51 through the drain port 60 to the outside. Drained. At this time, since the pair of terminals 61 provided in the drain port 60 are electrically connected via the leaked fluid, the control unit 62 can determine that water leakage has occurred. By notifying from the device 63, it is possible to appropriately notify the user that the water is leaking, and by blocking the intake channel 52, waste of fluid due to water leakage can be prevented.
JP 2004-239526 A

  However, in the conventional electric water heater 50, since the pair of terminals 61 provided in the drain port 60 of the main body case 51 are connected, it is determined that water leakage has occurred. Only water leaks occurring inward can be detected. From this, for example, when water leakage occurs in the water supply channel 53 outside the main body case 51 from the main body case 51 to the water supply port 59, the control unit 62 cannot recognize the water leakage, and the user It is impossible to notify the water leakage state, and it is impossible to prevent waste of fluid due to water leakage.

  In addition, since the pair of terminals 61 are provided in the drainage port 60 of the main body case 51, the drainage port 60 of the main body case 51 is immersed in water even when no water leakage occurs in the electric water heater 50. As a result, the control unit 62 determines that water leakage has occurred in the electric water heater 50.

  Then, the objective of this invention is providing the electric water heater which can detect the water leak which arose in the water supply port, without being influenced by the inundation which is not related to water leak.

  In order to solve the above-described problem, the electric water heater according to claim 1 is configured to be able to heat and store the fluid taken in via the intake channel and supply the stored fluid from the water supply port at the tip of the supply channel. A water storage tank, a shut-off valve capable of intermittently connecting the water intake path, a flow sensor capable of detecting that a fluid flow is generated in the water intake path between the shut-off valve and the water storage tank, and the flow sensor And a control unit that operates the shut-off valve to shut off the intake channel based on the detection information, and the control unit is a time setting that can set the water leakage determination time as a water leakage determination standard to an arbitrary length And a leakage determining means for determining a leakage when the duration of reception of detection information from the flow sensor exceeds the leakage determination time, and closing the shutoff valve from the open state when the leakage determination means determines that the leakage has occurred. Switch to the state And having a shut-off valve operating means for operating.

  The electric water heater according to claim 2 is the electric water heater according to claim 1, wherein the flow sensor can detect that a minute flow is generated in the fluid in the intake channel. And an impeller that rotates about an axis orthogonal to the direction in which the fluid flows.

  The electric water heater according to claim 3 is the electric water heater according to claim 1 or 2, wherein the control unit is charged by electric power supplied during a predetermined time of day. And is operated with electric power supplied during the predetermined time period, and operates with electric power from the internal charging means during other than the predetermined time period.

  The electric water heater according to claim 4, further comprising a charging unit that is charged by electric power supplied during a predetermined time of the day. In the water heater, the flow sensor and the shielding valve operate with electric power supplied during the predetermined time period, and operate with electric power from the charging unit except for the predetermined time period. And

  In the electric water heater according to claim 1, based on detection information from a flow sensor provided in a water intake passage between the shut-off valve and the water storage tank, the fluid flow in the water intake passage is generated beyond the leakage judgment time. Therefore, it is possible to detect water leakage that has occurred from the flow sensor provided in the intake channel through the water storage tank to the water supply port.

  Also, based on the detection information from the flow sensor provided in the intake channel between the shutoff valve and the water storage tank, a configuration that determines that there is water leakage when the fluid flow in the intake channel has exceeded the leakage determination time Therefore, even if inundation that is not related to leakage in the electric water heater occurs in the vicinity of the electric water heater, it is detected that the water leakage has occurred appropriately without being affected by the inundation. be able to.

  In the electric water heater according to claim 2, since a minute flow in the intake channel can be detected, water leakage generated in the intake channel from the flow sensor provided in the intake channel to the water supply port through the water storage tank Can be reliably detected.

  In the electric water heater according to claim 3, when the control unit is supplied with power only for a predetermined time period, for example, even when it is used under the condition of a late-night power contract, it is other than the predetermined time period. Since the control unit can be operated by the power from the internal charging means, it can be used all day.

  In the electric water heater according to claim 4, when the flow sensor and the shut-off valve are supplied with power only for a predetermined time period, for example, even when used under the conditions of a late-night power contract, Outside the time zone, the flow sensor and the shut-off valve can be operated by the electric power from the charging unit, so that it can be used all day.

  The present invention will be described in detail with reference to the embodiment shown in FIGS.

  FIG. 1 is a front view schematically showing the configuration of an electric water heater 10 according to the present invention.

  The electric water heater 10 includes a main body case 11 as shown in FIG. The main body case 11 has a box shape as a whole, and a drain port 12 is formed at the lower end to prevent water from accumulating. A water storage tank 13 is accommodated inside the main body case 11.

  The water storage tank 13 can store water inward, and is provided with a heater 14 for warming the stored water. The operation of the heater 14 is controlled by a control unit 15 which will be described later, and the water stored in the water storage tank 13 is warmed to a desired temperature. A water intake channel 16 and a water supply channel 17 are connected to the water storage tank 13. The intake channel 16 and the water supply channel 17 are pipes through which water can flow. In particular, the water supply channel 17 is formed in consideration of flowing hot water.

  The water supply path 17 constitutes a water supply-side pipe for using the water (hot water) stored in the water storage tank 13, and has a relief valve 18 and a water supply port 19.

  The relief valve 18 is a valve for adjusting the pressure in the water storage tank 13, and is provided at a location branched from the path from the water storage tank 13 to the water supply port 19. The relief valve 18 releases the pressure from the water storage tank 13 to the outside when the pressure in the water storage tank 13 becomes higher than necessary due to pressure fluctuation in the water storage tank 13, for example, by warming the stored water. The pressure in 13 is maintained in the desired state.

  The water supply port 19 is a place where a user acquires water (hot water) sent from the water storage tank 13 through the water supply channel 17 and is configured as a faucet that can be freely opened and closed. A water intake channel 16 forms a pipe on the water intake side to the water storage tank 13 for water (hot water) to the water supply port 19.

  Although not shown, the intake channel 16 is connected to a water pipe, and water taken from the water pipe can be sent to the water storage tank 13. In this intake channel 16, a shutoff valve 20, a pressure reducing valve 21, and a flow sensor 22 are provided in this order from the water pipe side.

  The shut-off valve 20 has a valve main body 20a and a driving means 20b for operating the valve main body 20a. When the water intake passage 16 can be opened and closed to interrupt the flow of water in the water intake passage 16, that is, when the intake passage 16 is opened, water intake is performed. A valve body 20a is provided in the intake passage 16 so as to block the intake passage 16 when the passage 16 is opened and closed. In this embodiment, the valve body 20a of the shut-off valve 20 is operated from the open state to the closed state, or is operated from the closed state to the open state. It is configured to keep the state itself. A pressure reducing valve 21 is provided in the intake passage 16 on the water storage tank 13 side of the shutoff valve 20.

  The pressure reducing valve 21 reduces the pressure of water taken from the water pipe into the intake channel 16. Thereby, the water storage tank 13 can store the water taken in via the intake channel 16. A flow sensor 22 is provided in the intake passage 16 on the water storage tank 13 side of the pressure reducing valve 21.

  When the flow sensor 22 detects the flow of water generated in the intake channel 16, the flow sensor 22 outputs a pulse signal according to the flow. The pulse signal from the flow sensor 22 is used for calculating the instantaneous flow rate in the electric water heater 10 and calculating the amount of hot water used per day. In the present embodiment, the flow sensor 22 is configured to include an impeller that rotates around an axis that is orthogonal to the direction in which water flows, that is, a so-called water wheel type impeller. It is possible to detect that a minute flow is generated in the water in the path 16. Specifically, the flow sensor 22 can output a pulse signal even when the flow is as small as 0.3 (L / min), that is, detects a flow as small as 0.3 (L / min). It is possible. The controller 15 is electrically connected to the flow sensor 22 and the drive means 20b of the shutoff valve 20.

  The control unit 15 is electrically connected to the operation unit 23 and the charging unit 24 in addition to the flow sensor 22 and the driving means 20b of the shutoff valve 20.

  The operation unit 23 can be operated by the user, and the operation information is transmitted to the control unit 15 so that the electric water heater 10 is in an operation state corresponding to the operation information, that is, an operation desired by the user. State. In this embodiment, the operation unit 23 is provided outside the main body case 11, and includes a display screen 23a and a speaker 23b (see FIG. 2).

  The charging unit 24 is configured to be charged with electric power supplied to the electric water heater 10 (in this embodiment, electric power supplied to the control unit 15). The charging unit 24 can supply power to the flow sensor 22 and the shut-off valve 20 when power is not supplied to the electric water heater 10 (in this embodiment, power is not supplied to the control unit 15). In the embodiment, it can be supplied via the control unit 15). In the present embodiment, the charging unit 24 is formed of a capacitor (not shown). As described above, the control unit 15 electrically connected to the flow sensor 22, the driving unit 20 b of the shutoff valve 20, the operation unit 23, and the charging unit 24 performs control related to water leakage determination.

  FIG. 2 is a block diagram schematically showing a configuration for controlling the water leakage determination in the control unit 15. As shown in FIG. 2, the control unit 15 includes a time setting unit 25, a water leakage determination unit 26, a shut-off valve operation unit 27, and an internal charging unit 28.

  The time setting means 25 is capable of acquiring the operation information made by the operation unit 23, and sets the water leakage determination time Tl (see FIG. 3). This water leakage judgment time Tl is a threshold value as to whether or not it is judged that the flow is caused by water leakage when the flow generated in the intake channel 16 is continued. That is, when a flow that continues beyond the water leakage determination time Tl occurs in the intake channel 16, it is determined that the flow is due to water leakage, and a flow that continues within the water leakage determination time Tl occurs in the water intake channel 16. If it is, it is determined that the flow is due to the use (supply) of water (hot water). In this embodiment, the water leakage determination time Tl is set according to the operation information by the time setting means 25 that has received the operation information performed by the operation unit 23 so that the user can set it appropriately. It is configured. Based on this water leakage determination time Tl, the water leakage determination means 26 determines water leakage.

  The water leakage determination means 26 can acquire the pulse signal from the flow sensor 22 and can acquire the information of the water leakage determination time Tl (see FIG. 3) set from the time setting means 25. Yes. The water leakage determination means 26 determines whether or not water leakage has occurred based on the length of time that the pulse signal from the flow sensor 22 is continuously acquired with reference to the acquired water leakage determination time Tl. Specifically, the water leakage determination means 26 starts counting the duration Tc (see FIG. 3) when receiving the pulse signal from the flow sensor 22, and counts the duration Tc while receiving the pulse signal. If the reception of the pulse signal is interrupted, the counting of the duration Tc is stopped and the duration Tc is reset to 0 and reset. At this time, when the duration Tc exceeds the water leakage determination time Tl, the water leakage determination means 26 determines that water leakage has occurred. In other words, the flow of the intake channel 16 detected by the flow sensor 22 is due to water leakage. Judge. When the water leakage determination means 26 determines that water leakage has occurred, the water leakage determination means 26 sends a water leakage generation signal LS to the operation unit 23 and the shutoff valve operation means 27.

  In the present embodiment, the water leakage determination unit 26 transmits a valve failure signal to the operation unit 23 when a pulse signal is received from the flow sensor 22 even after a predetermined time has elapsed after transmitting the water leakage occurrence signal LS. Send. For a certain period of time, even if the intake passage 16 is shut off at the position where the shut-off valve 20 is disposed as will be described later, the water leakage does not always stop, so the valve body 20a of the shut-off valve 20 is set to the closed position. This time is set in consideration of the time when the flow sensor 22 is assumed not to transmit the pulse signal. For this reason, when the valve body 20a of the shut-off valve 20 is in the closed position, the flow sensor 22 does not transmit a pulse signal immediately, that is, when the water leakage can be stopped immediately, it is necessary to set the above-described fixed time. A configuration may also be adopted in which a valve failure signal is transmitted to the operation unit 23 without waiting for a certain period of time to elapse.

  When receiving the water leakage occurrence signal LS, the operation unit 23 notifies that it is in a water leakage occurrence state. As a notification of this water leakage occurrence state, methods such as turning on a water leakage generation lamp, displaying a water leakage occurrence display on a display unit, and sounding an alarm sound can be considered. In the present embodiment, the operation unit 23 displays the occurrence of water leakage on the display screen 23a and sounds an alarm sound indicating that water leakage has occurred on the speaker 23b.

  Moreover, the operation part 23 will alert | report that it is in a valve failure state, if a valve failure signal is received. As a notification of the valve failure state, the operation unit 23 displays that the shut-off valve has failed on the display screen 23a, and the speaker 23b has a fault on the shut-off valve, as in the case of the water leak occurrence state. An audible alarm will sound.

  The shut-off valve operating means 27 can transmit a drive signal for operating the valve body 20 a to the drive means 20 b of the shut-off valve 20. When the shut-off valve operating means 27 receives the water leakage occurrence signal LS, the shut-off valve operating means 27 transmits a shut-off drive signal for operating the valve body 20a from the open state to the closed state to the drive means 20b. The drive means 20b that has received this cutoff drive signal operates the valve body 20a of the cutoff valve 20 from the open state to the closed state. Then, as described above, in the shutoff valve 20, the valve body 20 a is held in a closed state, so that the intake passage 16 is shut off at the position where the shutoff valve 20 is disposed.

  Here, since the flow sensor 22 detects the flow at the arrangement position in the intake channel 16, the cause of the water leakage causing the flow detected by the flow sensor 22 is from the flow sensor 22. Is also located on the downstream side, that is, on the water supply port 19 side. In addition, since the shutoff valve 20 is disposed on the upstream side of the flow sensor 22, that is, on the water pipe side (not shown) in the intake passage 16, the intake passage 16 is shut off at the position where the shutoff valve 20 is disposed. Accordingly, the supply of water from the intake channel 16 to the downstream side can be cut off, so that the water leakage causing the flow detected by the flow sensor 22 is stopped.

  Further, the control unit 15 of the electric water heater 10 opens and closes the valve body 20a of the shutoff valve 20 once in a time zone in which it is assumed that the user does not use the water (hot water) from the electric water heater 10. This prevents the valve body 20a of the shut-off valve 20 from sticking. In the present embodiment, the water leakage determination means 26 transmits a sticking prevention signal to the shut-off valve operation means 27 if it does not receive a pulse signal from the flow sensor 22 for more than 10 minutes between 3 o'clock and 4 o'clock at midnight. This is because water (hot water.) Is rarely used. Even if it is between 3:00 and 4 o'clock in the middle of the night, it is considered that water (hot water.) Is used. In order to confirm that is not used, it is a condition that the pulse signal from the flow sensor 22 is not continuously received for 10 minutes or more.

  When receiving the sticking prevention signal, the shutoff valve operating means 27 first sends a shutoff drive signal to the drive means 20b of the shutoff valve 20, and then sends an open drive signal. The drive means 20b that has received the cutoff drive signal operates the valve body 20a of the cutoff valve 20 from the open state to the closed state, and the drive means 20b that has received the release drive signal closes the valve body 20a of the cutoff valve 20. Operate from the mature state to the open state. Thereby, in the electric water heater 10, the shut-off valve 20 performs an opening / closing operation once a day, and the valve main body 20a of the shut-off valve 20 is prevented from adhering. Smooth operation is possible.

  In this embodiment, the electric water heater 10 is used under the condition of a late-night power contract. That is, in the contract time zone, the water stored in the water storage tank 13 is warmed by the heater 14, and the charging unit 24 and the internal charging means 28 of the control unit 15 are charged. Outside of the contract time period, the control unit 15 operates with the electric power from the internal charging means 28, and the shutoff valve 20 and the flow sensor 22 operate with the electric power from the charging unit 24. As described above, the electric water heater 10 is used under the condition of the late-night power contract, but can always operate regardless of whether or not it is in the contract time zone. When the power capacity of the internal charging means 28 of the charging unit 24 and the control unit 15 cannot cover the operation at all times other than the contract time zone, the control regarding the water leakage determination outside the contract time zone is performed for a certain time. It is good also as a structure performed at intervals.

  Next, the control regarding the water leak judgment in the control part 15 of the electric water heater 10 is demonstrated along the flowchart shown in FIG. In the example of FIG. 3, it is assumed that the water leakage judgment time Tl is set to 60 minutes by the operation of the operation unit 23 by the user, and the cause of the water leakage occurs in the circle A indicated by the alternate long and short dash line in FIG. And

  When receiving the pulse signal from the flow sensor 22, the water leakage determination means 26 proceeds to step S2 to start control relating to water leakage determination (step S1). The water leakage determination means 26 repeats step S1 without starting the control regarding water leakage determination until the pulse signal is received from the flow sensor 22.

  Since the water leakage determination means 26 has received the pulse signal from the flow sensor 22, it starts counting the duration Tc and starts control relating to water leakage determination (step S2).

  The water leakage determination means 26 continues counting the duration Tc until the pulse signal from the flow sensor 22 is interrupted, and if continuing the counting of the duration Tc, proceeds to step S4 and stops counting the duration Tc. If so, the process proceeds to step S5 (step S3).

  Since the water leakage determination means 26 continues to count the duration time Tc, that is, continuously receives the pulse signal from the flow sensor 22, it compares the duration time Tc with the water leakage determination time Tl and continues. If the time Tc exceeds the water leakage determination time Tl of 60 minutes, the process proceeds to step S6. If the duration Tc does not exceed the water leakage determination time Tl, the process returns to step S3 (step S4). If the duration Tc exceeds the water leakage judgment time Tl of 60 minutes, the flow in the intake channel 16 has continued beyond the water leakage judgment time Tl, so that the water leakage judgment means 26 has caused water leakage. It will be judged.

  If the water leakage determination means 26 stops counting the duration Tc in step S3, it is determined that the pulse signal from the flow sensor 22 is not due to water leakage, so the duration Tc is reset (set to 0). And return to step S1 (step S5).

  When it is determined that water leakage has occurred in step S4, the water leakage determination unit 26 transmits a water leakage generation signal LS to the operation unit 23 and the shutoff valve operation unit 27 (step S6).

  The shut-off valve operating means 27 that has received the water leakage occurrence signal LS transmits a shut-off drive signal to the drive means 20b of the shut-off valve 20, and the operation unit 23 that has received the water leak occurrence signal LS informs that a water leak has occurred. (Step S7).

  After transmitting the water leakage occurrence signal LS to the operation unit 23 and the shut-off valve operation unit 27, the water leakage determination unit 26 stands by until a predetermined time elapses (step S8). As described above, this fixed time is a time set in consideration of a time when the flow sensor 22 is assumed not to transmit a pulse signal after the valve body 20a of the shutoff valve 20 is in the closed position. Therefore, when the water leakage can be stopped immediately after the valve body 20a of the shutoff valve 20 is set to the closed position, step S8 can be eliminated.

  The water leakage determination means 26 proceeds to step S10 if a pulse signal is received from the flow sensor 22, and ends the flowchart of FIG. 3 if no pulse signal is received from the flow sensor 22 (step S9).

  The fact that the pulse signal is received from the flow sensor 22 in spite of the transmission of the water leakage occurrence signal LS to the shutoff valve operating means 27 means that the water intake passage 16 is not properly shut off by the shutoff valve 20. The water leakage determination means 26 transmits a valve failure signal to the operation unit 23 (step S10). When the operation unit 23 receives the valve failure signal, the operation unit 23 notifies the valve failure state and ends the flowchart of FIG.

  As described above, in the electric water heater 10, when water leakage occurs, the intake valve 16 is blocked by the shut-off valve 20, and the operation unit 23 notifies that the water leak has occurred. At this time, based on the pulse signal from the flow sensor 22 provided in the intake channel 16, it is determined that water leakage has occurred in the intake channel 16 when there is a continuous flow exceeding the water leakage determination time Tl. Because of the configuration, regardless of whether the cause of water leakage is inside or outside of the main body case 11 (in this embodiment, the outside (see reference A in FIG. 1)), it is confirmed that water leakage has occurred. Can be detected.

  In addition, since the electric water heater 10 is configured to determine whether or not water leakage has occurred based on the flow in the intake channel 16, for example, a drainage port of the main body case 11 can be obtained by water immersion that is not related to water leakage. Even if 12 is immersed in water, it is possible to appropriately determine whether or not water leakage has occurred without being affected by the flooding.

  Furthermore, in the electric water heater 10, since the flow sensor 22 can detect a minute flow in the intake channel 16, it is possible to reliably detect water leakage that occurs downstream of the flow sensor 22, that is, on the water supply port 19 side. can do. In general, the flow of water generated in the intake channel 16 due to the occurrence of water leakage is very small. Therefore, as in the flow sensor 57 of the conventional electric water heater 1 (see FIG. 4), the instantaneous flow rate is as follows. This is because it is not possible to transmit a stable pulse signal by reliably detecting a minute flow due to water leakage, assuming that it is used for calculating the amount of hot water and calculating the amount of hot water used per day.

  In the electric water heater 10, the internal charging means 28 is provided in the control unit 15, so that the power supply is supplied only during a predetermined time of the day, for example, at midnight as in the above-described embodiment. Even when used under the condition of the power contract, the control unit 15 can be operated by the power from the internal charging means 28 during the time period in which the power supply is not received. be able to.

  In the electric water heater 10, since the charging unit 24 is provided, the power supply is supplied only during a predetermined time of the day, for example, the condition of the late-night power contract as in the above-described embodiment. Even in the case where the flow sensor 22 is used, the flow sensor 22 and the shut-off valve 20 can be operated by the power from the charging unit 24 in a time zone in which no power is supplied. it can.

  Since the electric water heater 10 is provided with the internal charging means 28 of the charging unit 24 and the control unit 15, it is possible to change from a normal power contract for receiving power all day to a midnight power contract (one day) without providing a separate control power source. The contract to receive power supply only during a predetermined time period.

  In the electric water heater 10, since the user can appropriately set the water leakage judgment time Tl so as to match his / her usage situation, the user uses the water (hot water) and the water leakage judgment time Tl occurs in the intake channel 16. It is possible to prevent the current flow from being erroneously determined to be due to water leakage.

  Therefore, in the electric water heater 10, it is possible to detect water leakage that has occurred while reaching the water supply port 19 without being affected by inundation that is not related to water leakage.

  In the above-described embodiment, it is difficult for the internal charging means 28 provided in the control unit 15 to secure the power capacity for operating the flow sensor 22 and the shutoff valve 20. Although the charging unit 24 is provided for the operation of 20, the internal charging means 28 and the charging unit 24 can be used as long as the power capacity for operating the control unit 15, the flow sensor 22 and the shutoff valve 20 can be secured. However, the present invention is not limited to the above-described embodiments.

  In the above-described embodiment, the charging unit 24 and the internal charging unit 28 are provided. However, the charging unit 24 and the internal charging unit 28 need to be provided unless used under a condition where power is supplied only during a predetermined time of the day. Therefore, the charging unit 24 and the internal charging unit 28 can be appropriately omitted.

  Furthermore, in the above-described embodiment, the flow sensor 22 has a configuration having an impeller rotating around an axis orthogonal to the direction of water flow, that is, a configuration having a so-called water wheel type impeller, but water leakage occurs. As long as it can detect a minute flow of water in the intake channel 16 to the extent that it can be detected, the present invention is not limited to the above-described embodiment.

It is a front view which shows typically the electric water heater which concerns on this invention. It is a block diagram which shows roughly the structure of the control part for performing control regarding water leak determination. It is a flowchart which shows the control regarding the water leak determination in a control part. It is a front view which shows the conventional electric water heater typically.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electric water heater 13 Reservoir 15 Control part 16 Intake path 17 Water supply path 19 Water supply port 20 Shut-off valve 22 Flow sensor 24 Charging part 25 Time setting means 26 Water leak judgment means 27 Shut-off valve operation means 28 Internal charging means Tl Water leak judgment time Tc Duration

Claims (4)

The fluid taken in through the intake channel is stored in a heatable manner, and the stored fluid can be supplied from the water supply port at the tip of the water supply channel, the shutoff valve capable of interrupting the intake channel, the shutoff valve, A flow sensor capable of detecting the occurrence of a fluid flow in the intake channel with respect to the water storage tank, and a control for operating the shutoff valve to block the intake channel based on detection information from the flow sensor With
The control unit includes a time setting means capable of setting a water leakage determination time as a water leakage determination standard to an arbitrary length;
A leakage determining means for determining a leakage when the duration of reception of the detection information from the flow sensor exceeds the leakage determination time;
An electric water heater, comprising: a shut-off valve operating means that operates to switch the shut-off valve from the open state to the closed state when the water leak judging means determines that water leaks.   The flow sensor has an impeller that rotates about an axis perpendicular to the direction of fluid flow so that it can be detected that a minute flow is generated in the fluid in the intake channel. The electric water heater according to claim 1, wherein   The control unit includes an internal charging unit that is charged with electric power supplied during a predetermined time period of the day, and operates with the supplied electric power during the predetermined time period. 3. The electric water heater according to claim 1, wherein the electric water heater is operated by electric power from the internal charging means except in a band. 4.   The electric water heater according to any one of claims 1 to 3, further comprising a charging unit that is charged by electric power supplied during a predetermined time of day. The electric water heater is characterized in that the shielding valve operates with electric power supplied during the predetermined time period and operates with electric power from the charging unit during other than the predetermined time period.

Images