Electric water heater with intelligent heating control system

Abstract

The electric water heater with intelligent heating control system comprises an inner container, a water inlet pipe, a water outlet pipe and an intelligent heating control system, the water inlet pipe and the water outlet pipe are communicated with the inner container respectively, the intelligent heating control system comprises a controller, a detection unit and an execution unit, the execution unit comprises a heating pipe, the heating pipe is inserted into the inner container, the controller controls the heating pipe, a safety valve is arranged on the water inlet pipe, the detection unit further comprises a flow sensor arranged on the water inlet pipe, a first water pressure sensor and a first water temperature sensor arranged in the inner container, a second water pressure sensor and a second water temperature sensor arranged on the water outlet pipe, and the controller controls whether the heating pipe performs heating work through at least one of a flow signal L, a water pressure signal P1, a water temperature signal T1, a water pressure signal P2 and a water temperature signal T2 received by the flow sensor. The electric water heater with intelligent heating control system has the advantages of simple data detection and extraction, simple and clear determination logic without complex numerical comparison, low cost of intelligent control system, comprehensive and perfect control mechanism.

Description

Technical Field

[0001] This utility model relates to the field of electric water heater heating control, and in particular to an electric water heater with an intelligent heating control system. Background Technology

[0002] Electric water heaters have become indispensable household appliances in people's daily lives. However, in actual use, electric water heaters can suddenly malfunction, such as running dry due to lack of water, leaking inner tanks, or failure of the safety valve's backflow prevention function. These issues can cause the heating element to become unsuitable for heating, affecting the supply of hot water to users. Currently, there is no fully sophisticated intelligent detection and judgment mechanism to intelligently control the heating element and promptly warn users to prevent danger. Therefore, it is difficult to prevent such incidents before they occur, and they can easily cause serious property damage or personal injury.

[0003] In response to the above problems, individual manufacturers have tried to develop electric water heaters with intelligent heating control systems. For example, a Chinese invention application with the publication number CN113669901A and the title "A Water Heater Based on Cloud Processing According to Pressure Difference" discloses that: the water heater includes an electric heating device and a water tank. The electric heating device is arranged in the water tank. The water tank includes a water inlet pipe and a hot water outlet. The electric heating device includes a first pipe box, a second pipe box, and a coil pipe. The coil pipe is connected to the first pipe box and the second pipe box to form a closed circulation of heating fluid. An electric heater is arranged in the first pipe box; the coil pipe is one or more, and each coil pipe includes multiple arc-shaped tube bundles. The center lines of the multiple arc-shaped tube bundles are arcs concentric with the first pipe box. The ends of adjacent tube bundles are connected, so that the ends of the tube bundles form free ends of the tube bundles; a first electric heater and a second electric heater are respectively arranged in the first pipe box and the second pipe box; phase change fluid is filled in the first pipe box and / or the second pipe box. A first pressure sensor and a second pressure sensor are respectively arranged in the first pipe box and the second pipe box to detect the pressures in the first pipe box and the second pipe box. The first pressure sensor and the second pressure sensor are connected to the controller for data connection. The controller extracts the pressure data measured by the first pressure sensor or the second pressure sensor according to the time sequence, and obtains the pressure difference or the cumulative change of the pressure difference through the comparison of the pressure data in adjacent time periods. The controller is connected to a cloud server, and the cloud server is connected to a client. The controller transmits the cumulative data of the pressure difference or the change of the pressure difference to the cloud server, and then transmits it to the client through the cloud server. The client is a mobile phone, and an APP program is installed on the mobile phone. Users can select the working mode of automatic control or manual control on the client. The controller controls the heating according to the working mode selected by the control client. In the working mode of automatic control, when the first electric heater is heating and the second electric heater is not heating, for the pressure detected by the first pressure sensing element, if the pressure in the previous time period is P1 and the pressure in the adjacent subsequent time period is P2, and if P1 < P2 and the value of P2 - P1 is lower than the threshold, the controller controls the first electric heater to stop heating and the second electric heater to start heating; when the second electric heater is heating and the first electric heater is not heating, for the pressure detected by the second pressure sensing element, if the pressure in the previous time period is P1 and the pressure in the adjacent subsequent time period is P2, and if P1 < P2 and the value of P2 - P1 is lower than the threshold, the controller controls the second electric heater to stop heating and the first electric heater to start heating. For the technical solution described in this invention application, it is necessary to compare the pressure difference (P2 - P1) with the threshold to control whether the electric heater is heating. This solution requires not only detecting the pressure change but also determining the relationship between the pressure difference and the threshold, and the determination logic is slightly complicated. Moreover, the technical problem to be solved by this solution is to change the heating component through pressure detection to make the electric heater perform alternating heating, thereby increasing the heating effect and the scale removal effect.Therefore, it cannot truly address the issue of the heating element continuing to heat when the electric water heater malfunctions.

[0004] For example, Chinese invention application CN106247626A, entitled "An Electric Water Heater for Leak Detection," discloses that: the electric water heater includes a controller, an electric heating device, and a water tank; the electric heating device is disposed in the water tank; the electric heater includes a left pipe box, a right pipe box, and a heat exchange tube connecting the left and right pipe boxes; the electric heater is disposed in the left and / or right pipe boxes, and the heat exchange tube, the left pipe box, and the right pipe box form a closed loop for heating fluid; the electric heating device is also equipped with a pressure sensor for detecting the pressure within the electric heating device; the electric heating device, the pressure sensor, and the controller are connected to the controller, and the controller automatically controls the operation of the electric water heater according to the detected pressure; the controller is connected to a cloud server, and the cloud server is connected to the water heater client, wherein the controller transmits the measured pressure data to the cloud server, and then the cloud server transmits it to the client, which is a mobile phone with an APP installed, allowing the user to obtain the pressure data through the client. When the measured pressure is lower than a first pressure, the controller reduces the heating power of the electric heating device to the first power level; when the measured pressure is lower than a second pressure (lower than the first pressure), the controller reduces the heating power to the second power (lower than the first power); when the measured pressure is lower than a third pressure (lower than the second pressure), the controller reduces the heating power to the third power (lower than the second power); when the measured pressure is lower than a fourth pressure (lower than the third pressure), the controller reduces the heating power to the fourth power (lower than the third power); and when the measured pressure is lower than a fifth pressure (lower than the fourth pressure), the controller stops the heating. The technical solution described in this invention focuses on how to achieve automatic power control to improve heating efficiency and heating uniformity, but it still cannot provide a solution for how to handle heating control under various fault conditions.For example, Chinese invention application CN106016710A, entitled "An Electric Water Heater with Overheat Detection," discloses that: the electric water heater includes a controller, an electric heating device, and a water tank; the electric heating device is installed in the water tank; the electric heater includes a left tube box, a right tube box, and a heat exchange tube connecting the left and right tube boxes; the electric heater is installed in the left and / or right tube boxes, and the heat exchange tube, left and right tube boxes form a closed loop for heating fluid; the electric heating device is also equipped with a pressure sensor for detecting the pressure inside the electric heating device; the electric heating device, pressure sensor, and controller are connected to the controller; the controller determines whether the heating power is too high based on the detected pressure, thereby automatically controlling the operation of the electric water heater; the controller is connected to a cloud server, and the cloud server is connected to the water heater client; the controller transmits the measured pressure data to the cloud server, and then the cloud server transmits it to the client, which is a mobile phone with an APP installed, allowing the user to obtain the pressure data through the client. The device also includes an inlet pipe and an outlet pipe, each equipped with an inlet valve and an outlet valve, respectively. These valves are connected to a controller. If the detected pressure exceeds a certain threshold, the controller automatically increases the opening of both the inlet and outlet valves and transmits this information to the customer via a cloud server. When the measured pressure exceeds a first pressure, the controller reduces the heating power of the electric heating device to the first power level. When the measured pressure exceeds a second pressure (higher than the first), the controller reduces the heating power to the second power (lower than the first). When the measured pressure exceeds a third pressure (higher than the second), the controller reduces the heating power to the third power (lower than the second). When the measured pressure exceeds a fourth pressure (higher than the third), the controller reduces the heating power to the fourth power (higher than the third). When the measured pressure exceeds a fifth pressure (higher than the fourth), the controller stops the electric heating device. The technical solution described in this invention application focuses on how to achieve automatic power control to improve heating efficiency and uniformity, but it still fails to provide a solution for handling heating control under various fault conditions.

[0005] Finally, Chinese invention application CN110425745A, entitled "A Method for a Water Heater," discloses a method comprising: installing a pressure sensor in the inlet pipe outside the water heater body, the pressure sensor being used to detect water pressure; acquiring a pressure value indicating the water pressure; determining a frequency value associated with the pressure value; and determining the leakage status of the water heater based on the changing trends of the pressure value and the frequency value. This invention application obtains the pressure value detected by the pressure sensor in the inlet pipe outside the water heater body, determines the frequency value associated with the pressure value, and determines the leakage status of the water heater based on the changing trends of the pressure value and the frequency value. Although this invention application mentions "determining the leakage amount based on the frequency value" and "controlling the water heater to stop heating when the leakage amount is greater than a preset value," it partially discloses a heating control scheme under leakage faults. However, since the determination is based on the "frequency value," the data detection and extraction requirements are higher, increasing costs. Furthermore, this solution does not comprehensively address the intelligent control needs under various fault conditions. Utility Model Content

[0006] To address the shortcomings of existing technologies, this utility model provides an electric water heater with an intelligent heating control system and an intelligent heating control method, characterized by simple data detection and extraction, clear and simple judgment logic that eliminates the need for complex numerical comparisons, low cost of the intelligent control system, and comprehensive and perfect control mechanism.

[0007] The main technical solution adopted in this utility model application is as follows:

[0008] An electric water heater with an intelligent heating control system includes an inner tank, an inlet pipe, an outlet pipe, and an intelligent heating control system. The inlet pipe and the outlet pipe are respectively connected to the inner tank. The intelligent heating control system includes a controller, a detection unit, and an execution unit. The execution unit includes a heating element that extends into the inner tank. The controller is connected to the heating element and controls its heating operation. A safety valve is installed on the inlet pipe. The detection module further includes a flow sensor on the inlet pipe, a first water pressure sensor in the inner tank, a first water temperature sensor in the inner tank, a second water pressure sensor on the outlet pipe, and a second water temperature sensor on the outlet pipe. The controller controls whether the heating element performs heating operation by receiving at least one of the following: the flow signal L from the flow sensor, the water pressure signal P1 from the first water pressure sensor, the water temperature signal T1 from the first water temperature sensor, the water pressure signal P2 from the second water pressure sensor, and the water temperature signal T2 from the second water temperature sensor.

[0009] The intelligent heating control system also includes an alarm, which sounds an alarm upon receiving an alarm instruction from the controller.

[0010] The intelligent heating control system also includes a remote transmitter, which sends alarm information to the user after receiving an alarm indication from the controller, and / or sends working status information to the user after receiving a working status indication from the controller.

[0011] The controller first controls the heating element to preheat for a period of time t. During the preheating period t,

[0012] When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor does not increase, the water temperature signal T1 of the first water temperature sensor does not increase, the water pressure signal P2 of the second water pressure sensor does not change, and the water temperature signal T2 of the second water temperature sensor does not change, the controller determines that the inner tank is dry-burning due to lack of water and controls the heating element to stop heating; or...

[0013] When the flow sensor does not detect a flow signal L, the water pressure signal P1 of the first water pressure sensor increases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor remains unchanged, and the water temperature signal T2 of the second water temperature sensor remains unchanged, the controller determines that the water level in the inner tank is insufficient and controls the heating element to stop heating; or,

[0014] When the flow sensor does not detect a flow signal L, the water pressure signal P1 of the first water pressure sensor increases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor increases, and the water temperature signal T2 of the second water temperature sensor increases, the controller determines that there is sufficient water in the inner tank and controls the heating element to continue heating; or...

[0015] If the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor increases and then decreases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor increases and then decreases, and the water temperature signal T2 of the second water temperature sensor increases, then the controller determines that at least one of the following is true: the inner tank is leaking, hot water is being discharged from the outlet pipe, or the safety valve is leaking. The controller then controls the heating element to stop heating.

[0016] as well as,

[0017] The water pressure signal P1 of the first water pressure sensor exceeds the preset value P1 of the water pressure signal of the first water pressure sensor set by the controller. 设When the safety valve leaks, the water pressure signal P1 from the first water pressure sensor exceeds the preset value P1 of the water pressure signal. 设 If the temperature does not decrease after that, the controller determines that the safety valve has failed due to leakage, and the controller controls the heating tube to stop heating.

[0018] The controller presets a value P1 for the water pressure signal from the first water pressure sensor. 设 It is equal to the external leakage pressure value of the safety valve.

[0019] The preheating time period t is set such that the change in the water pressure signal P1 of the first water pressure sensor between the beginning and the end of the preheating time period t is not greater than the internal leakage pressure value of the safety valve.

[0020] If the flow sensor does not detect the flow signal L, the controller determines that the safety valve has failed due to internal leakage or that the cold water pressure is insufficient, or the controller determines that there is no backflow in the inlet pipe.

[0021] The controller first controls the heating element to preheat for a period of time t. During the preheating period t,

[0022] When the flow sensor detects an increase in the flow signal L, an increase in the water pressure signal P1 of the first water pressure sensor, no change in the water pressure signal P2 of the second water pressure sensor, and no change in the water temperature signal T2 of the second water temperature sensor, the controller determines that the inner tank is dry-burning due to lack of water or that the water level in the inner tank is insufficient and controls the heating element to stop heating; or,

[0023] When the flow sensor detects an increase in flow signal L, an increase in water pressure signal P1 from the first water pressure sensor, and an increase in water pressure signal P2 from the second water pressure sensor, the controller determines that there is sufficient water in the inner tank and controls the heating element to continue heating; or...

[0024] When the flow sensor detects a flow signal L, the water pressure signal P1 of the first water pressure sensor increases and then decreases, and the water pressure signal P2 of the second water pressure sensor increases and then decreases, the controller determines that at least one of the following is true: the inner tank is leaking, the safety valve's backflow prevention function is failing, hot water is being discharged from the outlet pipe, or the safety valve is leaking. Furthermore, if the decrease in the water pressure signal P1 of the first water pressure sensor occurs earlier than the decrease in the water pressure signal P2 of the second water pressure sensor, the controller determines that the inner tank is leaking, the safety valve's backflow prevention function is failing, or the safety valve is leaking, and controls the heating element to stop heating; or, if the decrease in the water pressure signal P1 of the first water pressure sensor occurs later than the decrease in the water pressure signal P2 of the second water pressure sensor, the controller determines that hot water is being discharged from the outlet pipe and controls the heating element to continue heating.

[0025] as well as,

[0026] The water pressure signal P1 of the first water pressure sensor exceeds the preset value P1 of the water pressure signal of the first water pressure sensor set by the controller. 设 When the safety valve leaks, the water pressure signal P1 from the first water pressure sensor exceeds the preset value P1 of the water pressure signal. 设 If the temperature does not decrease after that, the controller determines that the safety valve has failed due to leakage, and the controller controls the heating tube to stop heating.

[0027] Wherein, the maximum value of the water pressure signal P1 of the first water pressure sensor and the change between the maximum value of the water pressure signal P1 of the first water pressure sensor and the end of the preheating time period t are not greater than the internal leakage pressure value of the safety valve, and the value of the preheating time period t is greater than such that the change between the maximum value of the water pressure signal P1 of the first water pressure sensor and the end of the preheating time period t is not greater than the internal leakage pressure value of the safety valve.

[0028] According to the technical solution described in this utility model, the following beneficial effects are achieved: A comprehensive judgment of the water volume in the inner tank can be made using only a flow sensor installed on the inlet pipe, a first water pressure sensor and a first water temperature sensor installed in the inner tank, and a second water pressure sensor and a second water temperature sensor installed on the outlet pipe. Based on this, the heating element can be controlled to operate. The entire intelligent heating control system has few components and low manufacturing cost. It can determine whether the heating element is suitable for continued heating simply by analyzing the combination of changing trends and the timing of the changes. It can even complete the judgment without comparing the change difference with a specific value. The judgment mechanism is simple, logically clear, and does not require complex calculations, thus the controller's judgment program reacts quickly. Attached Figure Description

[0029] Figure 1 This is a structural diagram of each unit of an electric water heater.

[0030] Figure 2 This is a schematic diagram of an electric water heater with a double tank arranged vertically.

[0031] Figure 3 This is a schematic diagram of the structure combining a clamp with an integrated modular water temperature and pressure sensor.

[0032] Figure 4 for Figure 3 Schematic diagram of the longitudinal section structure.

[0033] 1 Inner tank, 2 Inlet pipe, 3 Outlet pipe, 30 sleeve, 4 Heating pipe, 5 Safety valve. Detailed Implementation

[0034] The technical solution of this utility model will be further described below with reference to the accompanying drawings:

[0035] See Figure 1-4As shown, an electric water heater with an intelligent heating control system includes an inner tank 1, an inlet pipe 2, an outlet pipe 3, and an intelligent heating control system. The inlet pipe 2 and the outlet pipe 3 are respectively connected to the inner tank 1. The intelligent heating control system includes a controller, a detection unit, and an execution unit. The execution unit includes a heating tube 4, which extends into the inner tank 1. The controller is connected to the heating tube 4 and controls the heating operation of the heating tube 4. A safety valve 5 is installed on the inlet pipe 2. The detection unit also includes a flow sensor installed on the inlet pipe 2, a first water pressure sensor installed in the inner tank 1, a first water temperature sensor installed in the inner tank 1, a second water pressure sensor installed on the outlet pipe 3, and a second water temperature sensor installed on the outlet pipe 3. The controller controls whether the heating tube 4 performs heating operation by receiving at least one of the following: the flow signal L from the flow sensor, the water pressure signal P1 from the first water pressure sensor, the water temperature signal T1 from the first water temperature sensor, the water pressure signal P2 from the second water pressure sensor, and the water temperature signal T2 from the second water temperature sensor. Preferably, the first water pressure sensor and the first water temperature sensor in the inner tank 1 can be integrated modular water pressure and temperature sensor products and installed at the bottom of the inner tank 1 cavity. In some specific cases, for example, when the electric water heater adopts a double tank arranged vertically, the first water pressure sensor and the first water temperature sensor can be located at the bottom of the lower inner tank 1 cavity; for another example, when the electric water heater adopts a double tank arranged horizontally, the first water pressure sensor and the first water temperature sensor can be located at the bottom of the inner tank 1 cavity where the inlet pipe 2 is located. Preferably, the second water pressure sensor and the second water temperature sensor on the outlet pipe 3 can also be integrated modular water pressure and temperature sensor products. This water pressure and temperature sensor product is installed through the positioning groove on the sleeve 30 connected to the outlet pipe 3 and detects the water pressure and water temperature in the outlet pipe 3. During installation, a sealing ring is also used for waterproof sealing. More preferably, the outlet pipe 3 is connected to multiple water terminals through the sleeve 30. In this application, the water volume in the inner tank can be determined using only a flow sensor installed on the inlet pipe, a first water pressure sensor and a first water temperature sensor installed in the inner tank, and a second water pressure sensor and a second water temperature sensor installed on the outlet pipe. Based on these, the heating element can be controlled to operate. The entire intelligent heating control system has few components and low manufacturing cost. In this application, the controller processes and analyzes the electrical signals fed back from each sensor (including signal conversion). The aforementioned flow signal L, water pressure signals P1 and P2, and water temperature signals T1 and T2 refer to the user-readable numerical signals after conversion by the controller.

[0036] See Figure 1As shown, the intelligent heating control system also includes an alarm, which sounds an alarm upon receiving an alarm instruction from the controller. In this application, when the controller determines that the heating element cannot continue heating, the controller sends an alarm instruction to the alarm, which then sounds an alarm to alert the user that the status is abnormal and requires immediate attention to prevent danger. Preferably, the alarm includes at least one of a buzzer, an indicator light, and a display screen (such as displaying a warning message on the screen).

[0037] See Figure 1 As shown, the intelligent heating control system also includes a remote transmitter. Upon receiving an alarm indication from the controller, the remote transmitter sends alarm information to the user, and / or upon receiving a working status indication from the controller, the remote transmitter sends working status information to the user. In this application, after receiving the alarm indication and / or working status indication from the controller, the remote transmitter sends a request to a remote relay station to send alarm information or working status information to the user through the remote relay station. In this application, the remote transmitter can not only send alarm information to the user, but also send working status information to the user upon request (the user sends a request to the remote relay station via a mobile terminal, the remote relay station then sends the request to the controller, and then the controller sends the working status information to the user's mobile terminal via the remote transmitter and the remote relay station). In addition to passively receiving alarm information, the user can also actively request to view the working status.

[0038] Furthermore, the controller first controls the heating element 4 to preheat for a period of time t. During the preheating period t,

[0039] When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor does not increase, the water temperature signal T1 of the first water temperature sensor does not increase, the water pressure signal P2 of the second water pressure sensor does not change, and the water temperature signal T2 of the second water temperature sensor does not change, the controller determines that the inner tank 1 is dry-burning due to lack of water and controls the heating element 4 to stop heating; or,

[0040] When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor increases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor remains unchanged, and the water temperature signal T2 of the second water temperature sensor remains unchanged, the controller determines that there is insufficient water in the inner tank 1 and controls the heating element 4 to stop heating; or,

[0041] When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor increases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor increases, and the water temperature signal T2 of the second water temperature sensor increases, the controller determines that there is sufficient water in the inner tank 1 and controls the heating element 4 to continue heating; or,

[0042] When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor increases and then decreases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor increases and then decreases, and the water temperature signal T2 of the second water temperature sensor increases, the controller determines that at least one of the following is true: the inner tank 1 is leaking, the outlet pipe 3 is discharging hot water, or the safety valve 5 is leaking. The controller then controls the heating tube 4 to stop heating.

[0043] as well as,

[0044] The water pressure signal P1 from the first water pressure sensor exceeds the preset value P1 set by the controller for the water pressure signal from the first water pressure sensor. 设 When safety valve 5 leaks, and the water pressure signal P1 from the first water pressure sensor exceeds the preset value P1, the safety valve 5 will leak. 设 If the temperature does not decrease after that, the controller determines that the safety valve 5 has failed due to leakage, and the controller controls the heating tube 4 to stop heating.

[0045] In this application, if the flow sensor does not detect a flow signal, the controller determines that there is no water entering the inlet pipe and no backflow. During the preheating time period t, the controller determines whether to continue heating based on the signal or a combination of signals fed back by at least one of the first water pressure sensor, the first water temperature sensor, the second water pressure sensor, and the second water temperature sensor. If the flow sensor does not detect a flow signal, the heating element's operation becomes the only possible factor affecting water pressure and temperature changes at the inner tank and outlet pipe. Specifically, if the heating element heats, but the water pressure P1 in the inner tank does not increase, the water temperature T1 in the inner tank does not increase, and the water pressure P2 and water temperature T2 at the outlet pipe remain unchanged (since no water pressure or temperature signals are displayed at the outlet pipe, "no change" is used), it indicates that the heating element is not submerged below the water surface in the inner tank. Therefore, the controller determines that the inner tank is dry-burning due to lack of water. If the heating element heats, but the water pressure P1 in the inner tank increases, the water temperature T1 in the inner tank increases, and the water pressure P2 and water temperature T2 at the outlet pipe remain unchanged (since no water pressure or temperature signals are displayed at the outlet pipe, "no change" is used), it indicates that the heating element is submerged below the water surface in the inner tank. Water enters below the inner tank surface, but insufficient water volume prevents changes in water pressure and temperature at the outlet pipe. When the heating element heats, if the water pressure P1 in the inner tank increases, the water temperature T1 in the inner tank increases, the water pressure P2 at the outlet pipe increases, and the water temperature T2 at the outlet pipe increases, it indicates sufficient water volume in the inner tank (and the upward trend of all signals also indicates no leakage). If the heating element heats, but the water pressure P1 in the inner tank increases and then decreases, the water temperature T1 in the inner tank increases, the water pressure P2 at the outlet pipe increases and then decreases, and the water temperature T2 at the outlet pipe increases, it indicates sufficient water volume in the inner tank. However, if there is pressure loss at the inner tank and / or the outlet pipe, causing the water pressure to increase and then decrease, it is determined that the inner tank is leaking, hot water is being discharged from the outlet pipe (because the inlet pipe is not receiving water, it is not suitable to continue heating), or the safety valve is leaking, making it unsuitable to continue heating. In this application, the water pressure P1 in the inner tank exceeds the preset value P1. 设 When the water pressure P1 in the inner tank exceeds the preset value P1, the safety valve will begin to leak. 设 If the temperature does not decrease after heating, the safety valve will leak and fail, and it is not suitable to continue heating.

[0046] Furthermore, the controller presets the water pressure signal P1 from the first water pressure sensor. 设 This is equal to the external leakage pressure value of safety valve 5. Preferably, the external leakage pressure value of safety valve 5 is between 0.75 MPa and 0.85 MPa.

[0047] Furthermore, the preheating time period t is set such that the change in the water pressure signal P1 of the first water pressure sensor between the start and end of the preheating time period t is no greater than the internal leakage pressure value of the safety valve 5. In this application, when there is no water inlet or backflow in the inlet pipe, the heating of the heating element becomes the only factor that may affect the water pressure and temperature changes at the inner tank and the outlet pipe. To ensure that the change in water pressure P1 in the inner tank does not affect whether cold water can be forced into the inner tank, that is, to exclude the situation where cold water cannot be forced in simply due to the change in water pressure P1 in the inner tank caused by heating, the preheating time period t is set such that the change in water pressure P1 in the inner tank (from the start to the end of the preheating time period t) is no greater than the internal leakage pressure value of the safety valve. Preferably, the internal leakage pressure value of the safety valve is between 0.08 MPa and 0.2 MPa. In this application, limiting the preheating time period t can also further prevent the generation of excessive water vapor due to heating of the heating element, thereby causing the water pressure and temperature at the outlet pipe to be affected by this interfering factor. Experience shows that for every 20°C increase in water temperature inside the tank, the water pressure will increase by about 0.005 MPa. To minimize the impact of water vapor generated during heating on the water pressure and temperature at the outlet pipe, the preheating time t should not allow the water temperature inside the tank to rise by more than 5°C.

[0048] Furthermore, if the flow sensor does not detect the flow signal L, the controller determines that the safety valve 5 has failed due to internal leakage or that the cold water pressure is insufficient, or that there is no backflow in the inlet pipe 2. In this application, the feedback signal from the flow sensor alone cannot enable the controller to control the heating element to "continue heating" or "stop heating." It is necessary to further combine the water pressure and water temperature signals at the inner tank and / or the outlet pipe. That is, a dual determination method combining the feedback from the flow sensor at the inlet pipe and the feedback from the water pressure and water temperature sensors at the inner tank and / or the outlet pipe is adopted, so that the determination result is more accurate and logically rigorous.

[0049] Alternatively, the controller can further control the heating element 4 to preheat for a period of time t. During the preheating period t,

[0050] When the flow sensor detects an increase in the flow signal L, the water pressure signal P1 from the first water pressure sensor increases, the water pressure signal P2 from the second water pressure sensor remains unchanged, and the water temperature signal T2 from the second water temperature sensor remains unchanged, the controller determines that the inner tank 1 is dry-burning due to lack of water or that the water volume in the inner tank 1 is insufficient, and controls the heating element 4 to stop heating; or,

[0051] When the flow sensor detects an increase in the flow signal L, an increase in the water pressure signal P1 from the first water pressure sensor, and an increase in the water pressure signal P2 from the second water pressure sensor, the controller determines that there is sufficient water in the inner tank 1 and controls the heating element 4 to continue heating; or,

[0052] When the flow sensor detects a flow signal L, the water pressure signal P1 of the first water pressure sensor increases and then decreases, and the water pressure signal P2 of the second water pressure sensor increases and then decreases, the controller determines that at least one of the following is true: the inner tank 1 is leaking, the backflow prevention valve 5 is malfunctioning, hot water is being discharged from the outlet pipe 3, or the safety valve 5 is leaking. Furthermore, if the decrease in the water pressure signal P1 of the first water pressure sensor occurs earlier than the decrease in the water pressure signal P2 of the second water pressure sensor, the controller determines that the inner tank 1 is leaking, the backflow prevention valve 5 is malfunctioning, or the safety valve 5 is leaking, and controls the heating element 4 to stop heating; or, if the decrease in the water pressure signal P1 of the first water pressure sensor occurs later than the decrease in the water pressure signal P2 of the second water pressure sensor, the controller determines that hot water is being discharged from the outlet pipe 3 and controls the heating element 4 to continue heating.

[0053] as well as,

[0054] The water pressure signal P1 from the first water pressure sensor exceeds the preset value P1 set by the controller for the water pressure signal from the first water pressure sensor. 设 When safety valve 5 leaks, and the water pressure signal P1 from the first water pressure sensor exceeds the preset value P1, the safety valve 5 will leak. 设 If the temperature does not decrease after that, the controller determines that the safety valve 5 has failed due to leakage, and the controller controls the heating tube 4 to stop heating.

[0055] In this application, when the flow sensor detects a flow signal, the controller determines that water is entering the inlet pipe or that backflow has occurred at the safety valve (similarly, a dual determination method is used, combining feedback from the water pressure and temperature sensors in the inner tank and / or the outlet pipe). During the preheating time period t, the controller determines whether to continue heating based on signals or combinations of signals from at least one of the first water pressure sensor, the first water temperature sensor, the second water pressure sensor, and the second water temperature sensor. When the flow sensor detects a flow signal, the heating element may cause changes in the water pressure and temperature at the inner tank and the outlet pipe. It needs further explanation regarding water temperature, as it is affected by the influx of cold water and cannot be accurately reflected (backflow from the safety valve has a significant impact on water pressure but a minor impact on water temperature). Therefore, in some cases, the feedback signal from the water temperature sensor is not a crucial basis for the determination. Therefore, based on the above, when the heating element heats up, if the water pressure P1 in the inner tank increases, the water pressure P2 at the outlet pipe remains unchanged, and the water temperature T2 at the outlet pipe remains unchanged (the outlet pipe cannot display water pressure and temperature signals, so "no change" is used to represent this), it indicates that the inner tank is dry-burning or has insufficient water. When the heating element heats up, if the water pressure P1 in the inner tank increases and the water pressure P2 at the outlet pipe increases (and both show an upward trend, indicating no pressure loss), it indicates that the water in the inner tank is sufficient. When the heating element heats up, if the water pressure P1 in the inner tank increases and then decreases, and the water pressure P2 at the outlet pipe increases and then decreases, it indicates that there is pressure loss (inner tank leakage, backflow prevention failure of the safety valve, hot water discharge from the outlet pipe, or safety valve leakage). Furthermore, to distinguish the discharge of hot water from the outlet pipe from other situations, it is necessary to further detect which of P1 and P2 decreases earlier (usually, if pressure loss occurs closer to a sensor first, that sensor is more likely to detect the pressure drop earlier). In this application, the water pressure P1 in the inner tank exceeds the preset value P1. 设 When the water pressure P1 in the inner tank exceeds the preset value P1, the safety valve will begin to leak. 设 If the temperature does not decrease after heating, the safety valve will leak and fail, and it is not suitable to continue heating.

[0056] Furthermore, the change between the maximum value of the water pressure signal P1 from the first water pressure sensor and the value at the end of the preheating time period t is not greater than the internal leakage pressure value of the safety valve. The value of the preheating time period t is greater than the value that ensures the change between the maximum value of the water pressure signal P1 from the first water pressure sensor and the value at the end of the preheating time period t is not greater than the internal leakage pressure value of the safety valve. In this application, when cold water is added to the inlet pipe (after adding water, the pressure change trend in the inner tank or at the outlet pipe is close to a part of a sine curve, i.e., from rapid change to stable change), the water pressure (P1 or P2) will reach its maximum value when the leakage point approaches the leakage critical value. At this time, because the water pressure increases, the inlet water volume decreases in turn, and the heating of the heating tube can play a more significant role at this time, so that the water pressure and water temperature change relatively simply due to heating. Therefore, the preheating time period t is lengthened (the heating time before the water pressure P1 in the inner tank reaches its maximum value cannot be deterministically analyzed due to the interference of the inlet water). When the inflow rate approaches the outflow rate, a pressure equilibrium point is reached (the water pressure at this point should be slightly less than the maximum water pressure). At this point, the heating element may no longer have a significant effect on the water temperature change (if the leakage is small, the heating element will significantly affect the water temperature; however, if the leakage is large, such as hot water being discharged from the outlet pipe, the heating element may not significantly affect the water temperature). Only when the water pressure P1 of the first water pressure sensor ends at the end of the preheating time period t can it be roughly considered to be significantly affected by the heating element. Therefore, a portion of the preheating time period t is limited to the range from the maximum value of the water pressure signal P1 of the first water pressure sensor to the end of the preheating time period t. In this application, to ensure that the water pressure change between the maximum value of the water pressure P1 in the inner tank and the end of the preheating time period t does not affect whether cold water can be forced into the inner tank, that is, to exclude the situation where cold water cannot be forced in due to the water pressure change between the maximum value of the water pressure P1 in the inner tank and the end of the preheating time period t caused solely by heating, the change value between the two is set to be no greater than the internal leakage pressure value of the safety valve. Preferably, the internal leakage pressure of the safety valve is between 0.08 MPa and 0.2 MPa. In this application, limiting the preheating time period t further prevents excessive water vapor from being generated due to heating by the heating element, thus avoiding interference with the water pressure and temperature at the outlet pipe. Experience shows that for every 20°C increase in water temperature inside the tank, the water pressure will increase by approximately 0.005 MPa. To minimize the impact of water vapor generated during heating on the water pressure and temperature at the outlet pipe, the preheating time period t should not cause the water temperature inside the tank to rise by more than 5°C.

[0057] Although the specific embodiments of this utility model have been described above, those skilled in the art can make changes to it without departing from the spirit and principle of this utility model. The scope of protection of this utility model is defined by its claims and their equivalents.

Claims

1. An electric water heater with an intelligent heating control system, comprising an inner tank, an inlet pipe, an outlet pipe, and an intelligent heating control system, wherein the inlet pipe and the outlet pipe are respectively connected to the inner tank, the intelligent heating control system comprises a controller, a detection unit, and an execution unit, the execution unit comprising a heating element extending into the inner tank, the controller being connected to the heating element and controlling the heating operation of the heating element, characterized in that: A safety valve is installed on the water inlet pipe. The detection unit also includes a flow sensor on the water inlet pipe, a first water pressure sensor in the inner tank, a first water temperature sensor in the inner tank, a second water pressure sensor on the water outlet pipe, and a second water temperature sensor on the water outlet pipe. The controller controls whether the heating tube performs heating operation by receiving at least one of the flow signal L from the flow sensor, the water pressure signal P1 from the first water pressure sensor, the water temperature signal T1 from the first water temperature sensor, the water pressure signal P2 from the second water pressure sensor, and the water temperature signal T2 from the second water temperature sensor.

2. The electric water heater with an intelligent heating control system according to claim 1, characterized in that: The intelligent heating control system also includes an alarm, which sounds an alarm upon receiving an alarm instruction from the controller.

3. The electric water heater with an intelligent heating control system according to claim 1, characterized in that: The intelligent heating control system also includes a remote transmitter, which sends alarm information to the user after receiving an alarm indication from the controller, and / or sends working status information to the user after receiving a working status indication from the controller.

4. The electric water heater with an intelligent heating control system according to any one of claims 1 to 3, characterized in that: The controller first controls the heating element to preheat for a period of time t. During the preheating period t... When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor does not increase, the water temperature signal T1 of the first water temperature sensor does not increase, the water pressure signal P2 of the second water pressure sensor does not change, and the water temperature signal T2 of the second water temperature sensor does not change, the controller determines that the inner tank is dry-burning due to lack of water and controls the heating tube to stop heating. or, When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor increases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor remains unchanged, and the water temperature signal T2 of the second water temperature sensor remains unchanged, the controller determines that there is insufficient water in the inner tank and controls the heating tube to stop heating. or, When the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor increases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor increases, and the water temperature signal T2 of the second water temperature sensor increases, the controller determines that there is sufficient water in the inner tank and controls the heating tube to continue heating. or, If the flow sensor does not detect the flow signal L, the water pressure signal P1 of the first water pressure sensor increases and then decreases, the water temperature signal T1 of the first water temperature sensor increases, the water pressure signal P2 of the second water pressure sensor increases and then decreases, and the water temperature signal T2 of the second water temperature sensor increases, then the controller determines that at least one of the following is true: the inner tank is leaking, hot water is being discharged from the outlet pipe, or the safety valve is leaking. The controller then controls the heating element to stop heating. as well as, The water pressure signal P1 of the first water pressure sensor exceeds the preset value P1 of the water pressure signal of the first water pressure sensor set by the controller. 设 When the safety valve leaks, the water pressure signal P1 from the first water pressure sensor exceeds the preset value P1 of the water pressure signal. 设 If the temperature does not decrease after that, the controller determines that the safety valve has failed due to leakage, and the controller controls the heating tube to stop heating.

5. The electric water heater with an intelligent heating control system according to claim 4, characterized in that: The controller presets a value P1 for the water pressure signal from the first water pressure sensor. 设 It is equal to the external leakage pressure value of the safety valve.

6. The electric water heater with an intelligent heating control system according to claim 4, characterized in that: The preheating time period t is set such that the change in the water pressure signal P1 of the first water pressure sensor between the start and end of the preheating time period t is not greater than the internal leakage pressure value of the safety valve.

7. The electric water heater with an intelligent heating control system according to claim 4, characterized in that: If the flow sensor does not detect the flow signal L, the controller determines that the safety valve has failed due to internal leakage or that the cold water pressure is insufficient, or the controller determines that there is no backflow in the inlet pipe.

8. The electric water heater with an intelligent heating control system according to any one of claims 1 to 3, characterized in that: The controller first controls the heating element to preheat for a period of time t. During the preheating period t... When the flow sensor detects a flow signal L, the water pressure signal P1 of the first water pressure sensor increases, the water pressure signal P2 of the second water pressure sensor remains unchanged, and the water temperature signal T2 of the second water temperature sensor remains unchanged, the controller determines that the inner tank is dry-burning due to lack of water or that the water volume in the inner tank is insufficient and controls the heating element to stop heating. or, When the flow sensor detects an increase in flow signal L, an increase in water pressure signal P1 from the first water pressure sensor, and an increase in water pressure signal P2 from the second water pressure sensor, the controller determines that there is sufficient water in the inner tank and controls the heating element to continue heating; or... When the flow sensor detects a flow signal L, the water pressure signal P1 of the first water pressure sensor increases and then decreases, and the water pressure signal P2 of the second water pressure sensor increases and then decreases, the controller determines that at least one of the following is true: the inner tank is leaking, the safety valve's backflow prevention function is failing, hot water is being discharged from the outlet pipe, or the safety valve is leaking. Furthermore, if the decrease in the water pressure signal P1 of the first water pressure sensor occurs earlier than the decrease in the water pressure signal P2 of the second water pressure sensor, the controller determines that the inner tank is leaking, the safety valve's backflow prevention function is failing, or the safety valve is leaking, and controls the heating element to stop heating; or, if the decrease in the water pressure signal P1 of the first water pressure sensor occurs later than the decrease in the water pressure signal P2 of the second water pressure sensor, the controller determines that hot water is being discharged from the outlet pipe and controls the heating element to continue heating. as well as, The water pressure signal P1 of the first water pressure sensor exceeds the preset value P1 of the water pressure signal of the first water pressure sensor set by the controller. 设 When the safety valve leaks, the water pressure signal P1 from the first water pressure sensor exceeds the preset value P1 of the water pressure signal. 设 If the temperature does not decrease after that, the controller determines that the safety valve has failed due to leakage, and the controller controls the heating tube to stop heating.

9. The electric water heater with an intelligent heating control system according to claim 8, characterized in that: The maximum value of the water pressure signal P1 of the first water pressure sensor and the change between the maximum value of the water pressure signal P1 of the first water pressure sensor and the end of the preheating time period t are not greater than the internal leakage pressure value of the safety valve. The value of the preheating time period t is greater than the value that makes the change between the maximum value of the water pressure signal P1 of the first water pressure sensor and the end of the preheating time period t not greater than the internal leakage pressure value of the safety valve.

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