CN211575557U

CN211575557U - Electric water heater

Info

Publication number: CN211575557U
Application number: CN201921644495.6U
Authority: CN
Inventors: 张斌; 盛保敬; 薛祥玉; 王爽; 陈小雷
Original assignee: Haier Smart Home Co Ltd; Qingdao Economic and Technological Development Zone Haier Water Heater Co Ltd
Current assignee: Haier Smart Home Co Ltd; Qingdao Economic and Technological Development Zone Haier Water Heater Co Ltd
Priority date: 2019-09-29
Filing date: 2019-09-29
Publication date: 2020-09-25
Anticipated expiration: 2029-09-29

Abstract

The utility model discloses an electric water heater, including inner bag, electric heating pipe and control module, electric heating pipe's one end stretches into to the inner bag in, and the power cord extends from electric heating pipe's other one end, and the power cord includes the ground wire, still includes electric leakage detection device, and electric leakage detection device sets up in the inner bag outside and the position department that is close to the ground wire, and non-contact sets up between electric leakage detection device's sensing element and the ground wire. The utility model discloses an electric water heater sets up induction element through the position department near the ground wire, its alternating current electric field around can the perception, when electric water heater takes place the ground wire electric leakage, no matter it switches on the return circuit, all can send alternating current electric field to the space, when having alternating current electric field around induction element, can produce the sensing signal, the detection principle of this scheme does not rely on the current balance of live wire and zero line, also need not to require leakage current to form the return circuit, the application scope of detection is more extensive, avoid taking place the condition of lou examining.

Description

Electric water heater

Technical Field

The utility model belongs to the technical field of add hot water system, specifically speaking relates to an electric water heater.

Background

When the electric leakage occurs, the live wire is generally connected with the ground wire, so that the ground wire is electrified. If the ground is good, the generated electricity will be conducted to the ground without danger to the human body. In order to prevent the poor grounding of the ground wire, the current electric equipment still needs to adopt the leakage protection measures, and for the electric water heater, the current main leakage protection measures comprise the protection of an electricity-proof wall, the detection of a leakage protection coil, the detection of an optical coupler and the like.

The leakage protection mode of the electricity-proof wall can protect the safety of the water outlet side, however, if other electric appliances and the electric water heater share the ground wire, the electricity can be leaked to other electric appliances through the ground wire, and at the moment, if other electric appliances are not protected, the human body can be in electric shock danger.

The leakage protection coil detects leakage by passing a live wire and a zero line through a detection coil simultaneously, and is used for detecting live wire current and zero line current, and when the live wire current and the zero line current are inconsistent, the leakage is judged to be leakage. However, the premise of this detection method is that the electrical appliance is normally connected to the ground, and the situation that the live wire current and the zero line current are inconsistent occurs only when the leakage occurs, if the electrical appliance is not normally connected to the ground, a loop cannot be formed with the ground, the live wire current and the zero line current are still the same when the leakage occurs, and the leakage cannot be detected by the leakage protection coil, which results in the detection leakage.

The scheme that the opto-coupler detected is whether to form the return circuit before detecting ground wire and wall, in case the electric leakage forms the return circuit and can detect, if the wall body does not have good ground connection, has great resistance to ground, then loop current undersize, and the mode that the opto-coupler detected will unable detection leakage current, causes the hourglass to examine.

Disclosure of Invention

The utility model discloses there is the technical problem who leaks to examine to current electric water heater to the ground wire electric leakage, provide an electric water heater, can solve above-mentioned problem.

In order to realize the purpose of the utility model, the utility model adopts the following technical scheme to realize:

an electric water heater comprises an inner container, an electric heating pipe and a control module, wherein one end of the electric heating pipe extends into the inner container, a power line extends out of the other end of the electric heating pipe, the power line comprises a ground wire and an electric leakage detection device, the electric leakage detection device is arranged on the outer side of the inner container and close to the position of the ground wire, a sensing element of the electric leakage detection device is in non-contact arrangement with the ground wire, and the electric leakage detection device is connected with an alarm module or the control module.

Further, the leakage detecting device further includes:

the input end of the amplifying circuit is connected with the sensing element, and the output end of the amplifying circuit is connected with the alarm module or the control module;

the power supply module is used for supplying power to the amplifying circuit;

a shielding enclosure within which portions of the ground wire and the inductive element are enclosed, the shielding enclosure for shielding electric fields located outside thereof.

Further, the induction element is an induction coil or a metal pickup plate.

Furthermore, the amplifying circuit comprises a first switch circuit and a voltage dividing circuit, one end of the voltage dividing circuit is connected with the power module, the other end of the voltage dividing circuit is connected with the ground through the first switch circuit, and the sensing signal generated by the sensing element is used for controlling the conduction state of the first switch circuit.

Furthermore, the amplifying circuit further comprises a second switch circuit, one end of the second switch circuit is connected with the power module, the other end of the second switch circuit is connected with the control end of the first switch circuit, and the control end of the second switch circuit is connected with the sensing element.

Furthermore, a filter capacitor is connected in parallel to two ends of the first switch circuit.

Further, the first switching circuit is a first NPN triode, the second switching circuit is a second NPN triode, a collector of the first NPN triode is connected to the voltage dividing circuit, an emitter of the first NPN triode is connected to ground, a base of the second NPN triode is connected to the sensing element, a collector of the second NPN triode is connected to the power supply, and an emitter of the second NPN triode is connected to the base of the first NPN triode.

Further, the amplifying circuit is an integrated operational amplifier.

Furthermore, the shielding case comprises a metal shielding layer and an insulating layer, wherein the metal shielding layer is positioned on the inner side, and the insulating layer is positioned on the outer side.

Furthermore, the control module is connected with a wireless communication module.

Compared with the prior art, the utility model discloses an advantage is with positive effect: the utility model discloses an electric water heater, position department through being close to the ground wire sets up induction element, its alternating current electric field around can the perception, when electric water heater takes place the ground wire electric leakage, be equivalent to ground wire and 220V alternating current electricity and be connected, no matter it switches on and forms the return circuit, all can send alternating current electric field to the space, when having alternating current electric field around induction element, can produce the sensing signal, it is very sensitive and accurate to the electric leakage detection of ground wire, the detection principle of this scheme does not rely on the current balance of live wire and zero line, also need not to require leakage current to form the return circuit, the application scope of detection is more extensive, avoid taking place the condition of hourglass detection.

Other features and advantages of the present invention will become more apparent from the following detailed description of the invention when read in conjunction with the accompanying drawings.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic structural diagram of an embodiment of an electric water heater proposed in this embodiment;

FIG. 2 is a schematic structural diagram of an embodiment of the leakage detecting device in FIG. 1;

FIG. 3 is a schematic block diagram of one embodiment of the electrical leakage detection apparatus of FIG. 1;

fig. 4 is a schematic circuit diagram of an embodiment of the leakage detecting device in fig. 2.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings and embodiments.

It should be noted that in the description of the present invention, the terms of direction or positional relationship indicated by the terms "inside", "outside", etc. are based on the directions or positional relationships shown in the drawings, which are only for convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In a first embodiment, the present invention provides an electric water heater, as shown in fig. 1 and fig. 2, which includes an inner container 11, an electric heating tube 12, and a control module 15, wherein one end of the electric heating tube 12 extends into the inner container 11, a power line 13 extends from another end of the electric heating tube 12, the power line 13 includes a ground line 131, and further includes a leakage detection device 14, the leakage detection device 14 is disposed at a position outside the inner container 11 and close to the ground line 131, as shown in fig. 2, a sensing element 141 of the leakage detection device 14 is disposed in a non-contact manner with the ground line 131, and the leakage detection device 14 is connected to an alarm module or the control module 15. The sensing element 141 can sense an alternating current field around and generate a sensing signal. Normally, the ground wire 131 is at zero potential, that is, no electric field is radiated to the space, when the ground wire 131 leaks, an ac voltage is applied to the ground wire 131, and the ground wire 131 may conduct the leakage to the inner container 11, the water in the inner container 11, the outer shell 17, the metal water pipe joint 17/18, the metal hanger, the wall, and the like, and even may be transmitted to other electrical appliances connected to the ground wire along with the ground wire 131. When electric water heater takes place the ground wire electric leakage, be equivalent to ground wire 131 and 220V alternating current and be connected, no matter it switches on and forms the return circuit, all can send alternating current electric field to the space, when having alternating current electric field around the inductive element, can produce the sensing signal, it is very sensitive and accurate to the electric leakage detection of ground wire, the detection principle of this scheme does not rely on the current balance of live wire and zero line, also need not to require leakage current to form the return circuit, the application scope of detection is more extensive, avoids taking place the condition of lou examining. When detecting the leakage signal, the leakage detection device 14 may directly send the signal to the alarm module for alarm prompt, or send the signal to the control module 15, and the control module takes protection control measures, such as controlling to disconnect the power supply of the water heater. The non-contact setting between the sensing element 141 and the ground wire 131 of the leakage detection device 14, when the ground wire 131 has leakage, the electric field radiated to the space can be detected by the sensing element 141, and meanwhile, the ground wire 131 can be prevented from directly contacting the sensing element 141, which causes the damage of the high-voltage alternating current to the induction type leakage detection device, and in addition, the ground wire 131 with leakage can be prevented from continuously transmitting the electricity to the leakage detection device, which leads to an increase of a leakage point, and further increases the risk of electric shock.

The leakage detection device 14 of this embodiment further includes an amplifying circuit 142, a power module 143, and a shielding case 144, where an input end of the amplifying circuit is connected to the sensing element, and an output end of the amplifying circuit is connected to the alarm module or the control module; the sensing element 141 senses the surrounding alternating current electric field to generate a sensing signal, generally, the sensing signal of the sensing element 141 is very weak and needs to be sent to the amplifying circuit 142, the amplifying circuit is used for amplifying the signal, the input end of the amplifying circuit 142 is connected with the sensing element 141, and the output end of the amplifying circuit is connected with the alarm module or the control module. The power module 143 is configured to provide power for the amplifying circuit 142, and may be implemented by directly using a battery capable of outputting direct current, or may be a power conversion module that inputs alternating current to convert the alternating current into direct current and supply the amplifying circuit 142 with the direct current; because the electric water heater needs to supply alternating current when working normally, in order to prevent the power line which supplies power normally from interfering the induction type electric leakage detection device and generating misjudgment, the scheme is that the shielding case 144 is arranged, at least the induction element 141 and part of the ground wire are sealed in the shielding case 144, for shielding an external electric field, preventing the electric field from entering into the shield case 144, causing interference with the inductive element 141, which can sense only the ac electric field of the detected object located inside the shielding case 144, the shielding case 144 can be implemented by a good metal conductor with an empty inner shell, the shielding case 144 can be connected to the ground by a separate wire, by grounding the shielding case 144, the same amount of positive charges induced on the surface of the shielding case 144 by the external ac electric field are discharged along the grounding wire to the ground plane, so that the power line generated by the external ac electric field source can be shielded outside the shielding case.

The sensing element 141 can be realized by a metal pickup sheet or an induction coil, but is not limited to the above-mentioned implementation scheme, the detected object can be wholly or partially enclosed in the shielding case 144, the sensing element 141 and the detected object are arranged in a non-contact manner, the two are arranged in a non-contact manner, when the detected object has electric leakage, the electric field radiated to the space can be detected by the sensing element 141, and meanwhile, the detected object can be prevented from directly contacting the sensing element 141, which causes the high-voltage alternating current to damage the sensing type electric leakage detection device, in addition, the detected object with electric leakage can be prevented from continuously transmitting the electric to the electric leakage detection device, which causes an electric leakage point to be increased, and further increases the electric shock risk.

The amplifying circuit 142 is configured to amplify a small signal sensed by the sensing element 141 until the small signal can be identified by the control module or the alarm module can be controlled to alarm, and preferably, in this embodiment, as shown in fig. 3, the amplifying circuit 142 includes a first switch circuit and a voltage dividing circuit, one end of the voltage dividing circuit is connected to the power module, the other end of the voltage dividing circuit is connected to ground through the first switch circuit, the dc power supply is configured to provide a dc operating voltage VCC for the voltage dividing circuit, a signal output terminal LDJC of the amplifying circuit 142 is disposed between the voltage dividing circuit and the first switch circuit, a sensing signal generated by the sensing element 141 is configured to control a conducting state of the first switch circuit, when no electric leakage occurs, the sensing element 141 does not have a sensing signal, therefore, the first switch circuit is not conducting, a conducting loop is not formed between the corresponding dc operating voltage VCC and ground, a signal state output by the signal output terminal jc ldl, when the leakage occurs, the sensing element 141 generates a sensing signal, when the voltage of the sensing signal is enough to turn on the first switch circuit, the first switch circuit is turned on, a conduction loop is formed between the corresponding direct current working voltage VCC and the ground, the signal output end LDJC has signal output, and the state of the signal output by the signal output end LDJC changes, which indicates the leakage. The signal can be directly used for controlling the alarm module to give an alarm, and can also be sent to the control module, and the control module takes further protective measures, such as cutting off a power supply and the like.

In order to improve the stability and the driving capability of the amplifying circuit 142, the amplifying circuit 142 further includes a second switch circuit, one end of the second switch circuit is connected to the power module, the other end of the second switch circuit is connected to the control end of the first switch circuit, and the control end of the second switch circuit is connected to the sensing element. The sensing element 141 generates a sensing signal for controlling the on-state of the first switch circuit, when the sensing signal generated by the leakage drives the first switch circuit to be on, the dc working voltage VCC output by the power module can be directly loaded on the first switch circuit through the second switch circuit, the second switch circuit is on, the state of the signal output by the signal output terminal LDJC changes, indicating the leakage, or no leakage.

In order to eliminate the interference wave introduced by the inductive element 141, the two ends of the first switch circuit are also connected in parallel with a filter capacitor C2, so as to improve the accuracy of the back-end detection and judgment.

As shown in fig. 4, the first switch circuit and the second switch circuit are respectively implemented by using an NPN transistor, and the voltage dividing circuit is implemented by using a voltage dividing resistor R1, where the first switch circuit is a first NPN transistor N1, the second switch circuit is a second NPN transistor N2, a collector of the first NPN transistor N1 is connected to the voltage dividing resistor R1, an emitter of the first NPN transistor N1 is connected to ground, a base of the second NPN transistor N2 is connected to the sensing element 141, a collector of the second NPN transistor N2 is connected to the power supply, and an emitter of the second NPN transistor N2 is connected to the base of the first NPN transistor N1. When the induced signal generated by the leakage reaches the turn-on voltage of the second NPN triode N2, the second NPN triode N2 is turned on, the base of the first NPN triode N1 is connected to the power supply module through the second NPN triode N2, and accordingly the first NPN triode N1 is turned on, and the state of the signal output by the signal output terminal LDJC changes, which indicates the leakage.

Of course, the amplifying circuit 142 is not limited to the above-mentioned components, and besides the above-mentioned switch circuit construction, it can also be implemented by using an integrated operational amplifier.

The shielding can 144 includes at least a metal shielding layer and an insulating layer (not shown), wherein the metal shielding layer is located at the inner side and the insulating layer is located at the outer side. The metal shielding layer is a closed or approximately closed metal shell or a metal mesh enclosure, the metal shielding layer plays a role in shielding an external electric field, the insulating layer plays a role in insulating the metal shielding layer from an external structure, and particularly for external metal parts, the metal shielding layer is prevented from conducting electricity to the metal shielding layer when the external structure is electrified, so that an internal circuit is damaged, and leakage detection is caused due to electric leakage caused by abnormal induction.

The control module is connected with the communication module for send away the electric leakage signal through wired or wireless mode, if can send the suggestion on user's mobile terminal equipment through radio communication, can also send on total power switch for cut off total power switch, not only can prevent the electric shock danger that the electric leakage of certain electrical equipment leads to, can also prevent the emergence of the electric shock danger that electric leakage conduction leads to other electrical apparatus.

The above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments described in the foregoing embodiments, or that equivalents may be substituted for elements thereof; such modifications and substitutions do not depart from the spirit and scope of the present invention, which is claimed.

Claims

1. An electric water heater comprises an inner container, an electric heating pipe and a control module, wherein one end of the electric heating pipe extends into the inner container, a power line extends out from the other end of the electric heating pipe, the power line comprises a ground wire, the electric water heater is characterized by further comprising an electric leakage detection device, the electric leakage detection device is arranged on the outer side of the inner container and close to the position of the ground wire, and an induction element of the electric leakage detection device is arranged in a non-contact mode with the ground wire.

2. The electric water heater according to claim 1, wherein the electrical leakage detection device further comprises:

the power supply module is used for supplying power to the amplifying circuit;

3. The electric water heater of claim 2, wherein the inductive element is an inductive coil or a metal pickup plate.

4. The electric water heater according to claim 2, wherein the amplifying circuit comprises a first switch circuit and a voltage dividing circuit, one end of the voltage dividing circuit is connected to the power module, the other end of the voltage dividing circuit is connected to ground through the first switch circuit, and the sensing signal generated by the sensing element is used for controlling the conducting state of the first switch circuit.

5. The electric water heater of claim 4, wherein the amplifying circuit further comprises a second switching circuit, one end of the second switching circuit is connected to the power module, the other end of the second switching circuit is connected to the control terminal of the first switching circuit, and the control terminal of the second switching circuit is connected to the sensing element.

6. The electric water heater according to claim 4, wherein a filter capacitor is connected in parallel to both ends of the first switch circuit.

7. The electric water heater according to claim 5, wherein the first switching circuit is a first NPN transistor, the second switching circuit is a second NPN transistor, a collector of the first NPN transistor is connected with the voltage dividing circuit, an emitter of the first NPN transistor is connected with ground, a base of the second NPN transistor is connected with the sensing element, a collector of the second NPN transistor is connected with a power supply, and an emitter of the second NPN transistor is connected with the base of the first NPN transistor.

8. The electric water heater according to claim 2, wherein the amplifier circuit is an integrated op amp.

9. The electric water heater according to any one of claims 2-8, wherein the shielding cage includes a metallic shielding layer on an inner side and an insulating layer on an outer side.

10. The electric water heater according to any one of claims 1-8, wherein a wireless communication module is connected to the control module.