Water heater and water tank thereof

Abstract

The invention discloses a water heater and a water tank thereof, and the water tank comprises an inner container which comprises a metal tank body; the anti-corrosion assembly comprises an electronic anode which extends into the inner container; the sacrificial anode extends into the inner container and comprises metal, and the reducibility of the metal is higher than that of the metal contained in the metal tank body; the control module is electrically connected to the metal tank body, the electronic anode and the sacrificial anode; wherein the control module is configured to electrically connect the sacrificial anode with the metal tank body when a power supply is switched off, disconnect the electrical connection between the sacrificial anode and the metal tank body when the power supply is switched on, load a positive voltage on the electronic anode, and load a direct current negative voltage on the metal tank body. No matter whether the water tank is powered on or powered off, the anti-corrosion assembly can effectively protect the metal tank body.

Description

Technical Field

[0001] The present invention relates to anti-corrosion technology, and in particular to a water heater and a water tank thereof. Background Art

[0002] The inner tank of the heat pump water tank is immersed in tap water with complex water quality for a long time. In order to prevent the inner tank from being corroded, the inner wall of the inner tank is enameled. However, there are some areas that are not enameled at the water pipe joints of the inner tank, and there is a risk of damage to the enamel layer of the inner tank. These areas that are not enameled and damaged are extremely prone to corrosion, and there is a risk of corrosion perforation of the inner tank.

[0003] The existing liner anti-corrosion solution is to use a magnesium rod in direct contact with the liner. The magnesium rod acts as an anode and sacrifices itself to provide protection for the liner corrosion risk area. The advantages of this liner anti-corrosion solution are simplicity, convenience, and controllable costs. The disadvantages are that the magnesium rod needs to be replaced regularly, and there are over-protection and under-protection states. The corrosion products of the magnesium rod will form scale, affecting water quality and user health. Summary of the invention

[0004] The present application provides a water tank, which comprises:

[0005] Liner, including metal tank body;

[0006] Corrosion-resistant components, including

[0007] an electronic anode extending into the inner tank;

[0008] a sacrificial anode extending into the inner tank and comprising a metal having a higher reducibility than the metal contained in the metal tank body;

[0009] A control module, electrically connected to the metal tank, the electronic anode and the sacrificial anode;

[0010] The control module is configured to electrically connect the sacrificial anode to the metal tank body when the power is disconnected, and to disconnect the electrical connection between the sacrificial anode and the metal tank body and load a positive voltage on the electronic anode and a DC negative voltage on the metal tank body when the power is connected.

[0011] In an illustrative embodiment, the control module includes:

[0012] A DC power supply module, comprising a positive output terminal electrically connected to the electronic anode and used to output a positive voltage, and a negative output terminal used to output a negative voltage;

[0013] A relay, comprising a moving contact electrically connected to the metal tank, a normally closed contact electrically connected to the sacrificial anode, and a normally open contact electrically connected to the negative output terminal;

[0014] The controller is configured to control the relay to be closed when the power is turned on, and to control the relay to be opened when the power is turned off.

[0015] In an illustrative embodiment, the relay further comprises:

[0016] The armature is fixed relative to the moving contact;

[0017] An elastic member, used for applying elastic force to the armature so that the movable contact contacts the normally closed contact;

[0018] a coil, which applies a magnetic attraction force opposite to the elastic force to the armature when energized so that the movable contact contacts the normally open contact; and

[0019] The control module further includes a switch device, wherein the switch device includes a collector electrically connected to one end of the coil, an emitter, and a base electrically connected to the controller;

[0020] The end of the coil not connected to the collector is used to load a positive voltage, the emitter is used to load a negative voltage, and the controller is configured to send a start signal to the switching device when the power is turned on to make the collector and the emitter conductive.

[0021] In an illustrative embodiment, the metal tank body is a stainless steel tank body or a carbon steel tank body with an enamel layer on the inner wall;

[0022] The sacrificial anode includes at least one of magnesium, aluminum, and zinc.

[0023] In an exemplary embodiment, the electronic anode includes an anode body, and the anode body is made of titanium or a titanium alloy.

[0024] In an exemplary embodiment, the electronic anode further includes a MMO coating coated on the anode body.

[0025] In an illustrative embodiment, the electronic anode is cylindrical, and the portion of the electronic anode exposed to water is coated with a MMO coating, and the length of the portion of the electronic anode exposed to water satisfies the following formula:

[0026] 150×π×d×L 1 >S×I

[0027] Where:

[0028] d represents the diameter of the electron anode;

[0029] L 1 Represents the length of the portion of the electron anode exposed to water;

[0030] S represents the inner surface area of ​​the metal tank;

[0031] I represents the limiting current density of the metal tank.

[0032] In an illustrative embodiment, the metal tank body is provided with a mounting hole;

[0033] The anti-corrosion assembly also includes an insulating base to block the mounting hole;

[0034] The electronic anode and the sacrificial anode are both fixed on the insulating base and are spaced apart from each other.

[0035] In an illustrative embodiment, a first through hole is provided on the insulating base, and two ends of the first through hole are respectively facing the inside of the inner liner and the outside of the inner liner;

[0036] The electronic anode is constructed as a strip structure penetrating the first through hole;

[0037] The anti-corrosion component further includes an insulating tube, which is sleeved on the electronic anode and penetrates the first through hole;

[0038] The sacrificial anode is further provided with a second through hole, and the second through hole is sleeved on one end of the insulating tube extending into the inner tank.

[0039] In an illustrative embodiment, the anti-corrosion assembly further includes a conductive cylinder sleeved on the insulating cylinder and passed through the first through hole, and a first nut;

[0040] The sacrificial anode is connected to one end of the conductive tube extending into the inner container, and one end of the conductive tube extending out of the inner container is provided with an external thread;

[0041] The first nut is screwed onto one end of the conductive tube extending out of the inner container and abuts against the insulating base, and the control module is electrically connected to the sacrificial anode through the conductive tube.

[0042] In an illustrative embodiment, the portion of the electronic anode extending into the inner container is provided with a limiting portion extending radially outward, and the sacrificial anode is arranged between the limiting portion and the insulating base;

[0043] An external thread is provided on one end of the electronic anode extending out of the inner container;

[0044] The anti-corrosion assembly also includes a first insulating gasket, a second nut and a second insulating gasket;

[0045] The first insulating gasket is clamped between the sacrificial anode and the limiting portion, the second nut is screwed on the end of the electronic anode extending out of the inner container, and the second insulating gasket is clamped between the second nut and the end of the conductive tube extending out of the inner container.

[0046] In an illustrative embodiment, a groove is provided on the insulating base, and one end of the sacrificial anode is inserted into the groove.

[0047] In an illustrative embodiment, the sacrificial anode is made of magnesium alloy, the metal tank is made of carbon steel, and the size of the sacrificial anode satisfies the following formula:

[0048] 2S 1 ×L 2 ×ρ Mg ÷M Mg >2×(X×S 2 ×T×ρ Fe )÷(87600×M Fe )

[0049] Where:

[0050] S 1 Represents the bottom area of ​​the sacrificial anode;

[0051] L 2 Indicates the length of the sacrificial anode;

[0052] ρ Mg Indicates the density of the sacrificial anode;

[0053] M Mg represents the molar mass of magnesium;

[0054] X represents the corrosion rate of carbon steel in the water contained in the liner;

[0055] S 2 Indicates the area of ​​the metal tank exposed to water;

[0056] T represents the design life of the sacrificial anode;

[0057] ρ Fe Indicates the density of carbon steel;

[0058] M Fe represents the molar mass of iron.

[0059] This embodiment also provides a water heater, which includes the water tank as described above.

[0060] The water tank in the present application, whether the power is on or off, the anti-corrosion component can effectively protect the metal tank body to prevent the metal tank body from being corroded. At the same time, the sacrificial anode is only consumed when the power is disconnected. During the service life of the water tank, the sacrificial anode is not consumed much and does not need to be replaced frequently, which has little impact on the overall water quality.

[0061] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by implementing the present application. Other advantages of the present application can be realized and obtained by the schemes described in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The accompanying drawings are used to provide an understanding of the technical solution of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the technical solution of the present application and do not constitute a limitation on the technical solution of the present application.

[0063] Figure 1 This is a schematic diagram of the structure of a water tank in an embodiment of the present application;

[0064] Figure 2 A schematic cross-sectional view of an anti-corrosion component in an embodiment of the present application;

[0065] Figure 3 for Figure 2 The enlarged schematic diagram of point A in the middle;

[0066] Figure 4 for Figure 2 The enlarged schematic diagram of point B in the middle;

[0067] Figure 5 A circuit diagram of a control module in an embodiment of the present application;

[0068] Figure 6 Schematic diagram of the life verification results of the MMO coating in the embodiment of the present application.

[0069] Reference numerals:

[0070] 100, water tank; 1, liner; 11, metal tank; 111, mounting hole; 20, control module; 21, relay; 211, coil; 212, moving contact; 213, normally closed contact; 214, normally open contact; 22, controller; 231, positive output terminal; 232, negative output terminal; 3, anti-corrosion component; 31, electronic anode; 311, limiter; 32, sacrificial anode; 321, second through hole; 33, insulating base; 331, first Through hole; 332, groove; T, switching device; c, collector; e, emitter; b, base; R1, first resistor; R2, second resistor; 35, first insulating gasket; 36, insulating cylinder; 37, conductive cylinder; 38, first nut; 39, second nut; 40, third nut; 41, first conductive gasket; 411, first terminal; 42, second insulating gasket; 43, fourth nut; 44, second conductive gasket; 441, second terminal. DETAILED DESCRIPTION

[0071] like Figure 1As shown, Figure 1 The structure of a water tank 100 of this embodiment is shown. The water tank 100 includes an inner tank 1 and an anti-corrosion component 3.

[0072] The inner tank 1 includes a metal tank body 11. The metal tank body 11 is the skeleton structure of the inner tank 1. The metal tank body 11 is made of metal, which may be iron, an iron alloy, copper or a copper alloy. The metal tank body 11 is made of, for example, steel plates welded together. The metal tank body 11 may be constructed in a cylindrical, capsule, box or spherical shape. The inner tank 1 is used to hold water, which may be tap water. An enamel layer is provided on the inner wall of the metal tank body 11, and the enamel layer does not completely cover the inner wall of the metal tank body 11. For example, a joint is provided on the metal tank body 11, and the enamel layer is not covered at the joint.

[0073] like Figure 1 , 2 As shown, the anti-corrosion component 3 is used to prevent the inner tank 1 from corrosion. The anti-corrosion component 3 includes an electronic anode 31, a sacrificial anode 32 and a control module 20. The electronic anode 31 and the sacrificial anode 32 are both extended into the inner tank 1, and the electronic anode 31 and the sacrificial anode 32 can contact the water in the inner tank 1. A gap is set between the electronic anode 31 and the sacrificial anode 32 and the metal tank body 11. The electronic anode 31 and the sacrificial anode 32 are separated from each other. The electronic anode 31, the sacrificial anode 32 and the metal tank body 11 are not in direct contact with each other.

[0074] The electronic anode 31 is a conductor. The shape of the electronic anode 31 is not limited, and can be a rod, a ring, a sphere or a ring. The electronic anode 31 can be made of corrosion-resistant metal. The reducibility of the metal contained in the electronic anode 31 is lower than the reducibility of the metal contained in the metal can body 11.

[0075] The sacrificial anode 32 is a conductor. The sacrificial anode 32 is a block structure, which can be a ring, a sphere, a cylinder or a strip. The material of the sacrificial anode 32 includes a metal, and the reducing property of the metal is higher than the reducing property of the metal contained in the metal can body 11.

[0076] The control module 20 is electrically connected to the metal tank body 11, the electronic anode 31 and the sacrificial anode 32 through wires. The control module 20 can be connected to an external power supply, which can be a mains supply. The control module 20 can control the on-off of the electrical connection between the metal tank body 11 and the sacrificial anode 32. For example, the metal tank body 11 and the sacrificial anode 32 are both electrically connected to a switch on the control module 20, and the control module 20 controls the on-off of the electrical connection between the metal tank body 11 and the sacrificial anode 32 by controlling the closing and opening of the switch. The control module 20 can also output a DC voltage, and a DC voltage can be loaded between the metal tank body 11 and the electronic anode 31. For example, a rectifier circuit is provided in the control module 20, which can convert the AC power input by the power supply into DC power. The voltage difference between the metal tank body 11 and the electronic anode 31 can be 12V.

[0077] The control module 20 is configured to disconnect the electrical connection between the metal tank body 11 and the sacrificial anode 32 and load a DC positive voltage on the electronic anode 31 and a DC negative voltage on the metal tank body 11 when the control module 20 is connected to the power supply. The control module 20 is also configured to electrically connect the sacrificial anode 32 to the metal tank body 11 and disconnect the electrical connection between the electronic anode 31 and the metal tank body 11 when the power supply is disconnected.

[0078] When water is contained in the inner tank 1, the water can conduct electricity due to impurities dissolved in the water, and the metal tank body 11, the sacrificial anode 32, and the electronic anode 31 are all in contact with the water. When the control module 20 is powered on, the control module 20 disconnects the electrical connection between the sacrificial anode 32 and the metal tank body 11, loads a DC positive voltage on the electronic anode 31, and loads a DC negative voltage on the metal tank body 11. The electronic anode 31, the control module 20, the metal tank body 11, and the water form a loop. The current output by the control module 20 flows through the electronic anode 31, the water, and the metal tank body 11 in sequence, and the control module 20 outputs electrons to the metal tank body 11 as the cathode. These electrons are provided to the substances in the water that can react chemically with the metal tank body 11 to perform electrochemical reactions, thereby preventing the metal tank body 11 from being corroded. When the control module 20 is disconnected from the power supply, such as when there is a power outage or the user actively cuts off the power supply, the control module 20 can no longer continue to load a DC voltage between the electronic anode 31 and the metal tank body 11 to protect the metal tank body 11 from corrosion. The control module 20 connects the electrical connection between the sacrificial anode 32 and the metal tank body 11, and the sacrificial anode 32, water and the metal tank body 11 form a loop. Since the metal reducing property of the sacrificial anode 32 is higher than that of the metal tank body 11, the sacrificial anode 32 transports electrons to the metal tank body 11. These electrons are provided to substances in the water that can react chemically with the metal tank body 11 for electrochemical reaction, thereby preventing the metal tank body 11 from being corroded.

[0079] In this way, whether the power is on or off, the anti-corrosion component 3 can effectively protect the metal tank body 11 to prevent the metal tank body 11 from being corroded. At the same time, the sacrificial anode 32 is only consumed when the power is disconnected. During the service life of the water tank 100, the sacrificial anode 32 is not consumed much and does not need to be replaced frequently, which has little impact on the overall water quality.

[0080] In an illustrative embodiment, Figure 1 , 5As shown, the control module 20 includes a DC power supply module (not shown in the figure), a relay 21 and a controller 22. The DC power supply module includes a positive output terminal 231 and a negative output terminal 232. The DC power supply module can output a DC voltage through the positive output terminal 231 and the negative output terminal 232, and the positive output terminal 231 outputs a positive voltage, and the negative output terminal 232 outputs a negative voltage. In some embodiments, the DC power supply module includes a step-down circuit and a rectifier circuit, the step-down circuit can output the AC power input by the power supply after stepping down, the input end of the rectifier circuit is electrically connected to the output end of the step-down circuit, and the rectifier circuit can convert the AC power output by the step-down circuit into DC power and output it. The output end of the rectifier circuit is electrically connected to the positive output terminal 231 and the negative output terminal 232. The positive output terminal 231 of the DC power supply module is electrically connected to the electronic anode 31 through a wire.

[0081] The relay 21 includes an insulating housing (not shown in the figure), a moving contact 212, a normally closed contact 213 and a normally open contact 214. The moving contact 212, the normally closed contact 213 and the normally open contact 214 are all connected to the insulating housing. The normally closed contact 213 and the normally open contact 214 are both static contacts. The moving contact 212 can be slidably connected to the insulating housing. The relay 21 has an on state and an off state. When the control end of the relay 21 is powered off, the relay 21 is in an off state, the moving contact 212 is in contact with the normally closed contact 213, and the moving contact 212 is separated from the normally open contact 214. When the control end of the relay 21 is powered on, the relay 21 is in an on state, the moving contact 212 is in contact with the normally open contact 214, and the moving contact 212 is separated from the normally closed contact 213.

[0082] The moving contact 212 is electrically connected to the metal can body 11 through a wire. The normally closed contact 213 is electrically connected to the sacrificial anode 32 through a wire. The normally open contact 214 is electrically connected to the negative output terminal 232 of the DC power supply module.

[0083] The controller 22 is a logic control unit, which may be a single chip microcomputer. The controller 22 is configured to energize the control end of the relay 21 when the control module 20 is powered on to control the relay 21 to close, so that the moving contact 212 is in contact with the normally open contact 214. When the control module 20 is powered off, the control end of the relay 21 is de-energized, the relay 21 is controlled to be disconnected, and the moving contact 212 is in contact with the normally closed contact 213.

[0084] In this way, when the control module 20 is powered on, the moving contact 212 of the controller 22 contacts the normally open contact 214, and the moving contact 212 is separated from the normally closed contact 213, so that the electrical connection between the metal tank body 11 and the sacrificial anode 32 is disconnected, the positive output terminal 231 of the DC power supply module outputs a positive voltage to the electron anode 31, and the negative output terminal 232 of the DC power supply module outputs a negative voltage to the metal tank body 11, thereby protecting the metal tank body 11 from corrosion. When the control module 20 is powered off, the moving contact 212 of the controller 22 contacts the normally closed contact 213, and the moving contact 212 is separated from the normally open contact 214, so that the metal tank body 11 is electrically connected to the sacrificial anode 32, the DC power supply module no longer outputs a DC voltage, and the sacrificial anode 32 provides electrons to the metal tank body 11 to prevent the metal tank body 11 from being corroded.

[0085] In an illustrative embodiment, the relay 21 further includes a coil 211, an armature (not shown in the figure) and an elastic member (not shown in the figure). The armature is relatively fixed to the moving contact 212. The armature and the moving contact 212 may be connected via an insulating member. The armature is slidably connected to the insulating housing of the relay 21.

[0086] The elastic member is connected to the armature and the insulating housing. The elastic member can be a spiral spring or a spring sheet. The elastic member applies elastic force to the armature so that the movable contact 212 has a tendency to keep in contact with the normally closed contact 213.

[0087] The coil 211 is fixed on the insulating housing. The two ends of the coil 211 are the control ends of the relay 21. The coil 211 is configured to apply a magnetic attraction force to the armature when energized, and the magnetic attraction force is opposite to the elastic force applied by the elastic member to the armature and is greater than the elastic force, so that the armature and the moving contact 212 move in a direction close to the normally open contact 214 until the moving contact 212 contacts the normally open contact 214.

[0088] The control module 20 also includes a switch device T, a first resistor R1 and a second resistor R2. The switch device T may be a triode or a MOS tube. The switch device T includes a collector c, an emitter e and a base b. The two ends of the first resistor R1 are electrically connected to the signal output end of the controller 22 and the base b of the switch device T, respectively. The two ends of the second resistor R2 are electrically connected to the base b and the emitter e of the switch device T, respectively. The collector c of the switch device T is electrically connected to one end of the coil 211, and a positive voltage is loaded on the other end of the coil 211 (i.e., the end not connected to the collector c), and a negative voltage is loaded on the emitter e of the switch device T. The end of the coil 211 loaded with the positive voltage may be electrically connected to the positive output end 231 of the DC power supply module, and the emitter e of the switch device T may be electrically connected to the negative output end 232 of the DC power supply module.

[0089] When the control module 20 is powered on, the controller 22 sends a start signal to the base b of the switch device T to control the collector c and the emitter e of the switch device T to be turned on. The start signal may be a high level signal.

[0090] In this way, when the power is turned on, the controller 22 can drive the switch device T to conduct, so that the coil 211 is energized, and after the coil 211 is energized, it can drive the armature to make the movable contact 212 contact the normally open contact 214. When the power is turned off, the controller 22 no longer drives the switch device T to conduct, so that the coil 211 is de-energized, and after the coil 211 is de-energized, the armature moves under the elastic force applied by the elastic member so that the movable contact 212 contacts the normally closed contact 213.

[0091] The first resistor R1 is a current limiting resistor, used to reduce the current between the base b and the emitter e to prevent damage to the switch device T. The second resistor R2 is a pull-down resistor, which can clamp the uncertain signal input by the base b at a high level and also play a current limiting role.

[0092] In an illustrative embodiment, the metal tank body 11 may be made of pure iron, pure copper, an iron alloy or a copper alloy. In some embodiments, the metal tank body 11 is a stainless steel tank body or a carbon steel tank body with an enamel layer on the inner wall. The stainless steel tank body is made of stainless steel material. The carbon steel tank body is made of carbon steel material, and the enamel layer provided on the carbon steel tank body cannot completely cover the inner wall of the carbon steel tank body.

[0093] The sacrificial anode 32 includes at least one of magnesium, aluminum and zinc. The sacrificial anode 32 can be made of magnesium, aluminum or zinc, or can be made of an alloy of magnesium, aluminum or zinc.

[0094] The reducibility of magnesium, aluminum, and zinc is higher than that of copper and iron. In electrochemical reactions, magnesium, aluminum, and zinc can provide electrons for copper and iron to prevent them from being corroded.

[0095] In an illustrative embodiment, the electronic anode 31 includes an anode body. The anode body can be configured as a strip. The anode body is made of titanium or a titanium alloy. The anode body can be made of TA1 material or TA2 material.

[0096] Titanium or its alloy has good electrical conductivity and corrosion resistance. It is not easily corroded even if immersed in tap water for a long time, and will not affect the water quality.

[0097] In an exemplary embodiment, the electronic anode 31 includes a MMO coating (mixed metal oxide coating). The MMO coating is coated on the outer surface of the anode body.

[0098] The MMO coating contains Ru, Ir, Ti, Pt and Co. The mass ratio of Ru, Ir, Ti, Pt and Co in the MMO coating satisfies the following relationship:

[0099] M Ru :M Ir :M Ti :M Pt : Co=x: (25-x): (75-y-z): y: z (where, x≤25, y≤10,

[0100] z≤10)

[0101] The MMO coating has very good corrosion resistance and can extend the life of the electronic anode 31. Figure 6 As shown, the electronic anode 31 with MMO coating is placed in 1000 mL of 1 mol / L sulfuric acid solution, and 2 A / cm 2 At constant current, the cell potential rises by more than 5 V after running for 650 h, indicating that the electronic anode 31 begins to fail. Therefore, it can be proved that the MMO coating has very good corrosion resistance and can maintain a long life even in sulfuric acid solution.

[0102] In an illustrative embodiment, the metal can body 11 is provided with a mounting hole 111. The mounting hole 111 is a through hole that passes through the wall surface of the metal can body 11. The mounting hole 111 may be a round hole.

[0103] The anti-corrosion component 3 includes an insulating base 33. The insulating base 33 can be constructed in a roughly disc shape. The insulating base 33 blocks the mounting hole 111 of the metal tank body 11. The insulating base 33 can be made of insulating material, such as engineering plastics. The insulating base 33 can be made of special engineering plastics PPS, high-temperature resistant nylon, PAEK, PI plastics, which have good high-temperature resistance and insulation properties, and are not easily damaged by aging even if the inner tank 1 contains hot water for a long time.

[0104] The electronic anode 31 is fixed on the insulating base 33, and at least a part of the electronic anode 31 extends into the inner container 1. The sacrificial anode 32 is fixed on the insulating base 33, and at least a part of the sacrificial anode 32 extends into the inner container 1. The sacrificial anode 32 and the electronic anode 31 are spaced apart from each other.

[0105] The insulating base 33 can fix the electronic anode 31 and the sacrificial anode 32 on the inner container 1 , and separate the electronic anode 31 and the sacrificial anode 32 from the metal can body 11 of the inner container 1 .

[0106] In an illustrative embodiment, Figure 2 , 4As shown, a first through hole 331 is provided on the insulating base 33. The first through hole 331 may be provided in the middle of the insulating base 33. One end of the first through hole 331 faces the inside of the inner container 1, and the other end of the first through hole 331 faces the outside of the inner container 1. The first through hole 331 may be a round hole.

[0107] The electronic anode 31 is configured as a strip structure. The electronic anode 31 may be configured as a straight strip structure. The cross section of the electronic anode 31 may be circular. The electronic anode 31 is penetrated through the first through hole 331. One end of the electronic anode 31 extends into the inner liner 1, and the other end of the electronic anode 31 extends out of the inner liner 1.

[0108] The anti-corrosion component 3 also includes an insulating tube 36. The insulating tube 36 is constructed as a cylindrical structure. The insulating tube 36 may be flexible. The insulating tube 36 is made of an insulating material. The insulating tube 36 may be made of plastic, and may be made of materials such as PP, PB, PVC, and HDPE. The insulating tube 36 is sleeved on one end of the electronic anode 31 close to the insulating base 33. The insulating tube 36 is inserted into the first through hole 331, and one end of the insulating tube 36 extends into the inner liner 1, and the other end of the insulating tube 36 extends out of the inner liner 1.

[0109] The sacrificial anode 32 is provided with a second through hole 321. The sacrificial anode 32 may be cylindrical, and the second through hole 321 extends along the central axis of the sacrificial anode 32. The sacrificial anode 32 is disposed in the inner tank 1, and the second through hole 321 of the sacrificial anode 32 is sleeved on one end of the insulating tube 36 extending into the inner tank 1. The insulating tube 36 is sandwiched between the sacrificial anode 32 and the electronic anode 31.

[0110] The insulating tube 36 separates the sacrificial anode 32 and the electronic anode 31 to prevent the sacrificial anode 32 and the electronic anode 31 from contacting each other.

[0111] In an illustrative embodiment, Figure 2 , 4 As shown, the anti-corrosion assembly 3 further includes a conductive cylinder 37 and a first nut 38. The conductive cylinder 37 is cylindrical. The conductive cylinder 37 is a conductor and can be made of a metal material. The conductive cylinder 37 can be made of stainless steel, such as 304 stainless steel or 430 stainless steel. The conductive cylinder 37 is sleeved on the insulating cylinder 36, and the conductive cylinder 37 is inserted into the first through hole 331 of the insulating base 33. One end of the conductive cylinder 37 extends into the inner liner 1, and the other end of the conductive cylinder 37 extends out of the inner liner 1.

[0112] The sacrificial anode 32 is connected to one end of the conductive tube 37 extending into the inner container 1. In this embodiment, one end of the second through hole 321 of the sacrificial anode 32 close to the insulating base is sleeved on the end of the conductive tube 37 extending into the inner container 1, and the sacrificial anode 32 and the conductive tube 37 are interference fit, so that the sacrificial anode 32 and the conductive tube 37 are tightly connected together. The second through hole 321 of the sacrificial anode 32 can be constructed as a stepped hole, and the end of the conductive tube 37 extending into the inner container 1 abuts against the hole shoulder of the second through hole 321. The control module 20 is electrically connected to the sacrificial anode 32 through the end of the conductive tube 37 extending out of the inner container 1.

[0113] An external thread is arranged on one end of the conductive tube 37 extending out of the inner container 1 , and a first nut 38 is screwed on the end of the conductive tube 37 extending out of the inner container 1 . The first nut 38 also abuts against a side of the insulating base 33 facing outside the inner container 1 .

[0114] In this way, the first nut 38 applies a pre-tightening force to the conductive cylinder 37 so that the sacrificial anode 32 and the first nut 38 can clamp the insulating base, so that the sacrificial anode 32 can be firmly fixed on the insulating base. At the same time, an electrical connection is formed between the conductive cylinder 37 and the sacrificial anode 32, and the control module 20 outside the inner tank 1 can be electrically connected to the sacrificial anode 32 through the conductive cylinder 37.

[0115] In an illustrative embodiment, Figure 3 As shown, a limiting portion 311 is provided on the side wall of the portion of the electronic anode 31 extending into the inner container 1, and the limiting portion 311 extends radially outward from the side wall of the sacrificial anode 32. The limiting portion 311 can be configured as an annular protrusion. The sacrificial anode 32 is located between the limiting portion 311 and the insulating base 33. One end of the sacrificial anode 32 faces the limiting portion 311, and the other end of the sacrificial anode 32 abuts against the insulating base 33.

[0116] The length of the electron anode 31 extending out of the inner container 1 is greater than the length of the conductive tube 37 extending out of the inner container 1. An external thread is provided on one end of the electron anode 31 extending out of the inner container 1, and the external thread can be provided near the end of the electron anode 31.

[0117] like Figure 3 , 4As shown, the anti-corrosion component 3 also includes a first insulating gasket 35, a second nut 39 and a second insulating gasket 42. The first insulating gasket 35 is made of an insulating material, such as silicone or rubber. The first insulating gasket 35 can be an annular gasket. The first insulating gasket 35 can be sleeved on the electronic anode 31. The first insulating gasket 35 is sandwiched between the end of the sacrificial anode 32 facing the limiting portion 311 and the side of the limiting portion 311 facing the sacrificial anode 32. The first insulating gasket 35 separates the limiting portion 311 from the sacrificial anode 32. The second nut 39 is screwed on the end of the electronic anode 31 extending out of the inner tank 1. The second insulating gasket 42 is made of an insulating material, such as silicone or rubber. The second insulating gasket 42 is sandwiched between the second nut 39 and the end of the conductive tube 37 extending out of the inner tank 1. The two ends of the insulating tube 36 can be respectively abutted against the first insulating gasket 35 and the second insulating gasket 42.

[0118] In this way, the second nut 39 applies a pre-tightening force to the electronic anode 31, and the limiting portion 311 of the electronic anode 31 and the second nut 39 clamp the first insulating gasket 35, the sacrificial anode 32, the conductive cylinder 37 and the second insulating gasket 42, so that the electronic anode 31 can be fixed. At the same time, the first insulating gasket 35 and the second insulating gasket 42 can prevent the electronic anode 31 and the sacrificial anode 32 from conducting electricity.

[0119] In an exemplary embodiment, a groove 332 is further provided on the insulating base 33. The groove 332 is provided on the side of the insulating base 33 facing the inner container 1. The groove 332 may be a circular groove 332. One end of the sacrificial anode 32 close to the insulating base 33 is inserted into the groove 332 of the insulating base 33.

[0120] The sacrificial anode 32 is inserted into the groove 332 of the insulating base 33 , so that the sacrificial anode 32 can be more firmly fixed on the insulating base 33 .

[0121] In an exemplary embodiment, the anti-corrosion component 3 further includes a first conductive gasket 41 , a second conductive gasket 44 , a third nut 40 and a fourth nut 43 .

[0122] The third nut 40 is screwed on the end of the conductive tube 37 extending out of the inner container 1, and the first conductive gasket 41 is sandwiched between the third nut 40 and the first nut 38. The edge of the first conductive gasket 41 is also provided with a first terminal 411, which is electrically connected to the moving contact 212 of the relay 21 through a wire.

[0123] The fourth nut 43 is screwed on the end of the electron anode 31 extending out of the inner container 1, and the second conductive gasket 44 is sandwiched between the fourth nut 43 and the second nut 39. The edge of the second conductive gasket 44 is also provided with a second terminal 441, which is electrically connected to the normally open contact 214 of the relay 21 through a wire.

[0124] The sacrificial anode 32 is electrically connected to the movable contact 212 of the relay 21 through the conductive cylinder 37, the first conductive gasket 41 and the first terminal 411 in sequence, and the electronic anode 31 is electrically connected to the normally open contact 214 of the relay 21 through the second conductive gasket 44 and the second terminal 441 in sequence.

[0125] In an exemplary embodiment, the sacrificial anode 32 is made of magnesium alloy, which may be extruded AZ31 magnesium alloy, and its open circuit potential (OCP) is -1.50 to -1.60 V (vs SCE). The metal tank 11 is made of carbon steel, and the size of the sacrificial anode 32 satisfies the following formula:

[0126] 2S 1 ×L 2 ×ρ Mg ÷M Mg >2×(X×S 2 ×T×ρ Fe )÷(87600×M Fe )

[0127] Where:

[0128] S 1 Indicates the bottom area of ​​the sacrificial anode 32, in cm 2 ;

[0129] L 2 represents the length of the sacrificial anode 32, in cm;

[0130] ρ Mg represents the density of the sacrificial anode 32, which is 1.78 g / cm 3 ;

[0131] M Mg represents the molar mass of magnesium;

[0132] X represents the corrosion rate of carbon steel in the water contained in the inner tank 1, and the value range of X is 0.05 to 0.13 mm / a;

[0133] S 2 It represents the area of ​​the metal tank 11 exposed to water, which is determined by the number and size of the joints on the metal tank 11. 2 Can be 200cm 2 ;

[0134] T represents the design life of the sacrificial anode 32, h;

[0135] ρ Fe Indicates the density of carbon steel, the value is 7.9g / cm 3 ;

[0136] M Fe represents the molar mass of iron.

[0137] In this way, the number of electrons generated by the sacrificial anode 32 after consumption is greater than the number of electrons required to protect the metal tank body 11 during power failure during the design life of the water tank 100, and the sacrificial anode 32 does not need to be replaced during the design life of the water tank 100.

[0138] For example, the design life of a 190L water tank 100 is 10 years, and the duration of an unexpected power outage is calculated as 10% of the design life, so T is 8760h. The diameter of a common sacrificial anode 32 is 2cm, so the length L of the sacrificial anode 32 can be calculated. 2 15.1cm>L 2 >5.8cm, length L of sacrificial anode 32 2 15.1cm>L 2 When the thickness is greater than 5.8 cm, the sacrificial anode 32 does not need to be replaced during the 10-year design life of the water tank 100 .

[0139] In an illustrative embodiment, the electronic anode 31 is cylindrical, and the portion of the electronic anode 31 exposed to water is coated with a MMO coating, and the length of the portion of the electronic anode 31 exposed to water satisfies the following formula:

[0140] 150×π×d×L 1 >S×I

[0141] Where:

[0142] d represents the diameter of the electron anode 31, m, and the value range may be 0.002 to 0.004 m;

[0143] L 1 represents the length of the portion of the electron anode 31 exposed to water, m;

[0144] 150 represents the rated working current density of the MMO coating, A / m 2 ;

[0145] S represents the inner surface area of ​​the metal can body 11, m 2 ;

[0146] I represents the limiting current density of the metal tank 11, mA / m 2 , its value is less than 15mA / m 2 .

[0147] In this way, when the length of the portion of the electronic anode 31 exposed in the water satisfies the above formula, it can ensure that the current emitted by the electronic anode 31 into the water is greater than the current value required for the corrosion protection of the metal tank body 11.

[0148] For example, the inner surface area of ​​the metal tank body 11 of a 190L water tank 100 is 2.055m 2 If the electron anode 31 with a diameter of 3 mm is used, the length L of the part of the electron anode 31 exposed in water is 1 Need to meet L 1 >0.022m.

[0149] This embodiment also provides a water heater, which includes the water tank 100 as described above. The water heater may be a heat pump water heater.

[0150] The present application describes multiple embodiments, but the description is exemplary rather than restrictive, and it is obvious to those skilled in the art that there may be more embodiments and implementations within the scope of the embodiments described in the present application. Although many possible feature combinations are shown in the drawings and discussed in the specific embodiments, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with any other feature or element in any other embodiment, or may replace any other feature or element in any other embodiment.

[0151] The present application includes and contemplates combinations of features and elements known to those of ordinary skill in the art. The embodiments, features and elements disclosed in the present application may also be combined with any conventional features or elements to form a unique invention scheme defined by the claims. Any features or elements of any embodiment may also be combined with features or elements from other invention schemes to form another unique invention scheme defined by the claims. Therefore, it should be understood that any feature shown and / or discussed in the present application may be implemented individually or in any appropriate combination. Therefore, except for the limitations made according to the attached claims and their equivalents, the embodiments are not subject to other restrictions. In addition, various modifications and changes may be made within the scope of protection of the attached claims.

[0152] In addition, when describing representative embodiments, the specification may have presented the method and / or process as a specific sequence of steps. However, to the extent that the method or process does not rely on the specific order of the steps described herein, the method or process should not be limited to the steps of the specific order described. As will be understood by those of ordinary skill in the art, other sequences of steps are also possible. Therefore, the specific sequence of the steps set forth in the specification should not be interpreted as a limitation to the claims. In addition, the claims for the method and / or process should not be limited to the steps of performing them in the order written, and those skilled in the art can easily understand that these sequences can be changed and still remain within the spirit and scope of the embodiments of the present application.

Claims

1. A water tank, It is characterized in that include: Liner, including metal tank body; Corrosion-resistant components, including an electronic anode extending into the inner tank; a sacrificial anode extending into the inner tank and comprising a metal having a higher reducibility than the metal contained in the metal tank body; A control module, electrically connected to the metal tank, the electronic anode and the sacrificial anode; The control module is configured to electrically connect the sacrificial anode to the metal tank body when the power is disconnected, and to disconnect the electrical connection between the sacrificial anode and the metal tank body and load a positive voltage on the electronic anode and a DC negative voltage on the metal tank body when the power is connected.

2. The water tank according to claim 1, It is characterized in that The control module comprises: A DC power supply module, comprising a positive output terminal electrically connected to the electronic anode and used to output a positive voltage, and a negative output terminal used to output a negative voltage; A relay, comprising a moving contact electrically connected to the metal tank, a normally closed contact electrically connected to the sacrificial anode, and a normally open contact electrically connected to the negative output terminal; The controller is configured to control the relay to be closed when the power is turned on, and to control the relay to be opened when the power is turned off.

3. The water tank according to claim 2, It is characterized in that The relay further comprises: The armature is fixed relative to the moving contact; An elastic member, used for applying elastic force to the armature so that the movable contact contacts the normally closed contact; a coil, which applies a magnetic attraction force opposite to the elastic force to the armature when energized so that the movable contact contacts the normally open contact; and The control module further includes a switch device, wherein the switch device includes a collector electrically connected to one end of the coil, an emitter, and a base electrically connected to the controller; The end of the coil not connected to the collector is used to load a positive voltage, the emitter is used to load a negative voltage, and the controller is configured to send a start signal to the switching device when the power is turned on to make the collector and the emitter conductive.

4. The water tank according to claim 1, It is characterized in that The metal tank body is a stainless steel tank body or a carbon steel tank body with an enamel layer on the inner wall; The sacrificial anode includes at least one of magnesium, aluminum, and zinc.

5. The water tank according to claim 1, It is characterized in that The electronic anode comprises an anode body, and the anode body is made of titanium or a titanium alloy.

6. The water tank according to claim 5, It is characterized in that The electronic anode further includes a MMO coating coated on the anode body.

7. The water tank according to claim 6, It is characterized in that The electronic anode is cylindrical in structure, and the part of the electronic anode exposed in water is coated with MMO coating, and the length of the part of the electronic anode exposed in water satisfies the following formula: 150×π×d×L 1 >S×I Where: d represents the diameter of the electron anode; L 1 Represents the length of the portion of the electron anode exposed to water; S represents the inner surface area of ​​the metal tank; I represents the limiting current density of the metal tank.

8. The water tank according to claim 6, It is characterized in that The MMO coating contains Ru, Ir, Ti, Pt and Co elements; The mass ratio of the Ru element, the Ir element, the Ti element, the Pt element and the Co element is x:(25-x):(75-y-z):y:z; Among them, x≤25, y≤10, z≤10.

9. A water tank according to any one of claims 1 to 8, It is characterized in that The metal tank body is provided with a mounting hole; The anti-corrosion assembly also includes an insulating base to block the mounting hole; The electronic anode and the sacrificial anode are both fixed on the insulating base and are spaced apart from each other.

10. The water tank according to claim 9, It is characterized in that The insulating base is provided with a first through hole, and two ends of the first through hole are respectively facing the inside of the inner container and the outside of the inner container; The electronic anode is constructed as a strip structure penetrating the first through hole; The anti-corrosion component further includes an insulating tube, which is sleeved on the electronic anode and penetrates the first through hole; The sacrificial anode is further provided with a second through hole, and the second through hole is sleeved on one end of the insulating tube extending into the inner tank.

11. The water tank according to claim 10, It is characterized in that The anti-corrosion assembly further includes a conductive tube and a first nut which are sleeved on the insulating tube and passed through the first through hole; The sacrificial anode is connected to one end of the conductive tube extending into the inner container, and one end of the conductive tube extending out of the inner container is provided with an external thread; The first nut is screwed onto one end of the conductive tube extending out of the inner container and abuts against the insulating base, and the control module is electrically connected to the sacrificial anode through the conductive tube.

12. The water tank according to claim 11, It is characterized in that The portion of the electronic anode extending into the inner container is provided with a limiting portion extending radially outward, and the sacrificial anode is arranged between the limiting portion and the insulating base; An external thread is provided on one end of the electronic anode extending out of the inner container; The anti-corrosion assembly also includes a first insulating gasket, a second nut and a second insulating gasket; The first insulating gasket is clamped between the sacrificial anode and the limiting portion, the second nut is screwed on the end of the electronic anode extending out of the inner container, and the second insulating gasket is clamped between the second nut and the end of the conductive tube extending out of the inner container.

13. The water tank according to claim 11, It is characterized in that The insulating base is provided with a groove, and one end of the sacrificial anode is inserted into the groove.

14. A water tank according to any one of claims 1 to 8, It is characterized in that The sacrificial anode is made of magnesium alloy, the metal tank is made of carbon steel, and the size of the sacrificial anode satisfies the following formula: 2S 1 ×L 2 ×ρ Mg ÷M Mg >2×(X×S 2 ×T×ρ Fe )÷(87600×M Fe ) where: S 1 Represents the bottom area of ​​the sacrificial anode; L 2 Indicates the length of the sacrificial anode; ρ Mg Indicates the density of the sacrificial anode; M Mg represents the molar mass of magnesium; X represents the corrosion rate of carbon steel in the water contained in the liner; S 2 Indicates the area of ​​the metal tank exposed to water; T represents the design life of the sacrificial anode; ρ Fe Indicates the density of carbon steel; M Fe represents the molar mass of iron.

15. A water heater, It is characterized in that Comprising a water tank as claimed in any one of claims 1 to 14.

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