Heating tube, dry heater and water heater

Abstract

Disclosed are a heating tube (1), a dry heater and a water heater. The heating tube (1) includes a tube body (11) and two heating elements (12). The tube body (11) has a first end and a second end opposite to the first end. The two heating elements (12) are arranged side by side in the tube body, and each heating element (12) includes a heating section (121), a first lead-out rod (122) and a second lead-out rod (123) respectively provided at two opposite ends of the heating section (121). Two first lead-out rods (122) are electrically interconnected inside the first end, and two second lead-out rods (123) extend from respective second ends to form two terminals.

Description

TECHNICAL FIELD

[0001] The present invention relates to the technical field of water heaters, and in particular to a heating tube, a dry heater and a water heater.BACKGROUND

[0002] Dry heaters are used as heating elements in storage-type electric water heaters. Dry heaters generally have a heating tube and a heater sleeve. The heater sleeve is fixed inside the inner tank, and the heating tube is provided in the heater sleeve. When the heating tube is working, the heating tube is energized to convert electrical energy into thermal energy, and the heat is exchanged with the water in the inner tank through the heater sleeve, thereby heating the water in the inner tank.

[0003] The heating tube of the existing dry heater needs to be folded in half, hydraulically formed and other processes during the processing. Since a heating wire is inserted through the heating tube and the heating tube is filled with magnesium oxide powder, during the folding and hydraulic forming process, external force squeezes the pipe material of the heating tube and the magnesium oxide powder in the heating tube, which will affect the heating tube. The resistance wire causes mechanical damage, which can easily cause premature damage to the resistance wire during use.SUMMARY

[0004] The main purpose of the present invention is to propose a heating tube, a dry heater and a water heater, aiming to simplify processing and reduce the risk of wire breakage.

[0005] In order to achieve the above purpose, the heating tube proposed in the present invention comprises: a tube body and two heating elements.

[0006] In an embodiment of the present invention, the tube body is provided with a first end and a second end opposite to the first end.

[0007] In an embodiment of the present invention, two heating elements are arranged side by side in the tube body, and each heating element comprises a heating section, a first lead-out rod and a second lead-out rod provided at two opposite ends of the heating section.

[0008] In an embodiment of the present invention, two first lead-out rods are electrically interconnected inside the first end, and two second lead-out rods extend from respective second ends to form two terminals.

[0009] In an embodiment of the present invention, the heat tube further comprises a first insulation plug provided at the first end of the tube body and blocking an opening of the tube body.

[0010] In an embodiment of the present invention, the first insulation plug is configured to wrap an electrical connection part of the two first lead-out rods.

[0011] In an embodiment of the present invention, the first insulation plug is provided inside the tube body.

[0012] In an embodiment of the present invention, an end surface of the first insulation plug away from the heating element is flush with an end surface of the first end of the tube body.

[0013] In an embodiment of the present invention, the two first lead-out rods are fixed by welding.

[0014] In an embodiment of the present invention, the two first lead-out rods are electrically interconnected through an electrical connector.

[0015] In an embodiment of the present invention, the two first lead-out rods are of an integrally bent part.

[0016] In an embodiment of the present invention, the heating section is a resistance wire, the resistance wire is arranged in a spiral shape and is sleeved at an end of the first lead-out rod.

[0017] In an embodiment of the present invention, the heating tube further comprises a second insulation plug provided at the second end of the tube body and blocking an opening of the tube body, the second insulation plug, the first insulation plug and the tube body are enclosed to form a seal cavity, the two heating sections are provided in the seal cavity, and the two second lead-out rods are arranged to pass through the second insulation plug.

[0018] In an embodiment of the present invention, the second insulation plug is provided inside the second end of the tube body, and an end surface of the second insulation plug away from the first end is flush with an end surface of the second end of the tube body.

[0019] In an embodiment of the present invention, the seal cavity is filled with electric insulation and heat conduction material, the electric insulation and heat conduction material is configured to isolate the two heating elements and isolate the heating element from a wall of the tube body.

[0020] In an embodiment of the present invention, the tube body is an electric insulation and heat conduction member.

[0021] In order to achieve the above purpose, the present invention also provides a dry heater, comprising: a heater sleeve with one end closed and the other end open; an installation base connected to an open end of the heater sleeve and open at a position corresponding to the heater sleeve; and the heating tube as described above, the heating tube is provided in the heater sleeve, and a terminal of the heating tube is provided outside the heater sleeve.

[0022] In order to achieve the above purpose, the present invention also provides a water heater, comprising an inner tank and the heating tube as described above, and the heating tube is suitable for heating water in the inner tank.

[0023] In order to achieve the above purpose, the present invention also provides a water heater, comprising the dry heater as described above and an inner tank, a closed end of a heater sleeve is configured to extend into the inner tank, and an installation base is fixed to an aperture of the inner tank.

[0024] In the heating tube of the technical solution of the present invention, two heating elements are arranged side by side in the tube body. The heating element comprises a heating section, a first lead-out rod and a second lead-out rod respectively provided at two opposite ends of the heating section. The two first lead-out rods are electrically interconnected inside the first end of the tube body, and the two second lead-out rods extend from respective second ends of the tube body to form two terminals for electrical connection with the power supply outside the tube body, to realize the normal heating function of the two heating elements in the tube body. In this embodiment, by extending the two second lead-out rods of the heating element from the same end of the tube body, there is no need to fold the tube body in half using hydraulic pressure, which simplifies the processing technology and reduces the mechanical damage to the tube body and the heating element. At the same time, it is convenient to control the outer diameter of the tube body, and the processing accuracy is higher, which greatly reduces the gap between the heating tube and the inner wall of the heater sleeve, ensures that the heat of the heating tube is transferred to the sleeve in time and heat exchanges with water, to ensure the life of the heating tube. In addition, by electrically connecting the two first lead-out rods inside the first end of the tube body, there is no need to additionally consider the insulation problem of the conductor being exposed or extending to the outside of the tube body, further simplifying the processing process and improving production efficiency.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly describe the embodiments of the present invention or the technical solutions in the related art, accompanying drawings needed to be used in the description of the embodiments or the related art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts. FIG. 1 is a schematic structural view of a heating tube according to an embodiment of the present invention. FIG. 2 is a partial enlarged view at portion A in FIG. 1. FIG. 3 is a partial enlarged view at portion B in FIG. 1. FIG. 4 is a schematic structural view of a case in which two first lead-out rods are fixed by welding according to an embodiment of the present invention. FIG. 5 is a schematic structural view of a case in which two first lead-out rods are fixed through an electrical connector according to an embodiment of the present invention. FIG. 6 is a schematic structural view of a heating element according to an embodiment of the present invention. FIG. 7 is a schematic structural view of a heating sleeve and an installation base according to an embodiment of the present invention. FIG. 8 is a schematic structural view of a water heater according to an embodiment of the present invention. Description of reference signs

[0026] reference signnamereference signname1heating tube1521positioning hole11tube body16electric insulation and heat conduction material12heating element2heater sleeve121heating section3installation base122first lead-out rod4innertank123second lead-out rod41aperture13electrical connector51water inlet pipe151first insulation plug52water outlet pipe152second insulation plug

[0027] The realization of the purpose, functional features and advantages of the present invention will be further described in conjunction with the embodiments, with reference to the accompanying drawings.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some rather than all of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of the present invention.

[0029] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention, the directional indications are only used to explain the relative position relationship, movement conditions, etc. between the components in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0030] At the same time, the meaning of "and / or" in the text comprises three parallel solutions. Taking "A and / or B" as an example, it comprises solution A, or solution B, or a solution that A and B satisfy at the same time.

[0031] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying its relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first" and "second" may explicitly or implicitly comprise at least one of these features. In addition, the technical solutions in the various embodiments can be combined with each other, but it must be based on what a person of ordinary skill in the art can implement. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such a combination of technical solutions does not exist, nor is it within the scope of the present invention.

[0032] The heating tube of the existing dry heater needs to be integrally folded in half, hydraulic forming and other processes during the processing process. It is processed from a long straight round tube into a long straight oval tube body after being folded in half. Since a heating wire is inserted through the heating tube and the heating tube is filled with magnesium oxide powder, during the hydraulic forming process, external force squeezes the tube and the magnesium oxide powder in the heating tube, causing mechanical damage to the resistance wire in the heating tube. It is easy to cause the resistance wire to be damaged in advance during use. The existing technology has the problem that the heating tube has complicated processing technology and the resistance wire is easy to break.

[0033] Based on this, the present invention proposes a heating tube 1, which aims to eliminate the need to bend the electric heating tube as a whole, simplify the processing technology, and reduce the risk of wire breakage. The structure of the heating tube 1 will be described below by way of embodiment.

[0034] In the embodiment of the present invention, as shown in FIG. 1 to FIG. 3 and FIG. 6, the heating tube 1 comprises a tube body 11 and two heating elements 12.

[0035] The tube body 11 has a first end and a second end opposite to the first end. The two heating elements 12 are provided side by side in the tube body 11, and each heating element 12 comprises a heating section 121, a first lead-out rod 122 and a second lead-out rod 123 provided at two opposite ends of the heating section 121. Two first lead-out rods 122 are electrically interconnected inside the first end, and two second lead-out rods 123 respectively extend from respective second ends to form two terminals.

[0036] In this embodiment, the tube body 11 plays the role of installing the heating element 12 and conducting the heat of the heating element 12 away. It can be understood that the insulation between the tube body 11 and the heating element 12 prevents leakage problems caused by electrical conduction between the heating element 12 and the tube body 11. At the same time, the tube body 11 can quickly conduct the heat inside to the outside. In an embodiment, the tube body 11 can be a metal tube or a non-metal tube with good thermal conductivity. The tube body 11 itself can be made of insulating material or non-insulating material. When the tube body 11 is made of non-insulating material, the tube body 11 can be isolated and insulated from the heating element 12 by filling the inside of the tube body 11 with insulating material. In an embodiment, the cross-sectional shape of the tube body 11 can be circular, semicircular, square, triangular or other special shapes. In practical applications, the tube body 11 can be configured as a circular tube for easy molding.

[0037] The two heating elements 12 are arranged side by side in the tube body 11. It can be understood that the two heating elements 12 are arranged at intervals in the tube body 11. The heating element 12 comprises a heating section 121, a first lead-out rod 122 and a second lead-out rod 123. The heating section 121 can be a resistance wire structure with high heating efficiency. The two heating sections 121 are arranged in parallel and spaced apart. The first lead-out rod 122 and the second lead-out rod 123 play the role of wire leads. The first lead-out rods 122 of the two heating elements 12 are electrically interconnected to electrically connect the two heating sections 121. The two second lead-out rods 123 extend from respective second ends of the tube body 11 to form two terminals. The two terminals are a positive terminal and a negative terminal for electrical connection with external power components, to realize the energization and heating function of the two heating sections 121 in the tube body 11. It can be seen from this that the two second lead-out rods 123 of the two heating elements 12 extend from the same end of the tube body 11, and there is no need to fold the tube body 11 in half using hydraulic pressure, which simplifies the process and reduces mechanical damage to the tube body 11 and the resistance wire.

[0038] In addition, this embodiment realizes the electrical conduction function of the two heating sections 121 through the electrical connection of the two first lead-out rods 122. Since the resistance wire is usually made of metal or alloy materials and has a certain elasticity, compared with the solution of directly bending the resistance wire, in this embodiment, the two first lead-out rods 122 can play a role in supporting and limiting the two heating sections 121 to prevent the deformation of the resistance wire from causing uneven heating temperatures, and to prevent the resistance wire from contacting the inner wall of the tube body 11, ensuring electrical safety.

[0039] In practical applications, the first lead-out rod 122 can be a conductive rod, a wire, a conductive sheet, or other conductive structure. It can be understood that the heating section 121 is a resistance wire, and the resistance wire is in a spiral shape. The first lead-out rod 122 has a connection end, and the cross-sectional area of the first lead-out rod 122 gradually decreases from the middle of the first lead-out rod 122 to the connection end so that the connection end forms a tapered shape, which is conducive to the spiral resistance wire being sleeved at the connection end, increasing the contact area between the first lead-out rod 122 and the resistance wire, and ensuring the electrical connection between the first lead-out rod 122 and the resistance wire. In an embodiment, the connection method between the second lead-out rod 123 and the heating section 121 can refer to the connection method between the first lead-out rod 122 and the heating section 121, which will not be repeated here.

[0040] In practical applications, the inside of the tube body 11 is filled with magnesium oxide powder with good thermal conductivity. The compactness of the magnesium oxide powder is related to the thermal conductivity. In the related technology, in order to realize the folding and extrusion of the heating tube 1 as a whole, the magnesium oxide powder filled inside needs to be in a loose state, and the heat transfer efficiency of loose magnesium oxide powder is poor, which causes the internal heating wire to overheat and cause dry burning. In this embodiment, there is no need to bend the heating tube 1 as a whole, and there is no need to reduce the compactness of the magnesium oxide powder. This can ensure the compactness of the magnesium oxide powder and improve the thermal conductivity efficiency, thereby preventing the heating wire from dry burning and overheating, and reducing the occurrence of malfunctions.

[0041] It should be noted that the two first lead-out rods 122 are electrically interconnected inside the first end of the tube body 11, so that the two first lead-out rods 122 will not be exposed or extend outside the tube body 11. Compared with the solution in the related art that the two first lead-out rods 122 extend to outside of the tube body 11 for electrical connection, the heating tube 1 of this embodiment only needs to undergo a normal sealing process (the sealing itself needs to be insulated), and there is no need to additionally consider the insulation problem of the conductor being exposed or extending outside the tube body 11. In addition, there is no additional issues regarding the connection of the external insulation structure and the temperature resistance of the material, that is, the heating tube 1 of this embodiment has a simpler process and higher production efficiency.

[0042] In the heating tube 1 of the technical solution of the present invention, two heating elements 12 are arranged side by side in the tube body 11. The heating element 12 comprises a heating section 121 and a first lead-out rod 122 and a second lead-out rod 123 respectively provided at both ends of the heating section 121. By electrically connecting the two first lead-out rods 122 inside the first end of the tube body 11, the two second lead-out rods 123 respectively extend out of the second end of the tube body 11 to form two terminals for electrical connection with the power supply outside the tube body 11, to realize the normal heating function of the two heating elements 12 in the tube body 11. In this embodiment, the two second lead-out rods 123 of the heating element 12 extend from the same end of the tube body 11, thereby eliminating the need to fold the tube body 11 in half using hydraulic pressure, simplifying the processing technology, and reducing the mechanical damage to the tube body 11 and the heating element 12. At the same time, it is convenient to control the outer diameter of the tube body 11, and the processing precision is higher, which greatly reduces the gap between the heating tube 1 and the inner wall of the heater sleeve 2, ensuring that the heat of the heating tube 1 is transferred to the sleeve in time and is exchanged with water to ensure the life of the heating tube 1. In addition, by electrically connecting the two first lead-out rods 122 inside the first end of the tube body 11, there is no need to additionally consider the insulation problem of the conductor being exposed or extending to the outside of the tube body 11, further simplifying the processing process and improving production efficiency.

[0043] Furthermore, the electrical connection method of the two first lead-out rods 122 can be determined according to actual conditions.

[0044] In an embodiment of the present invention, as shown in FIG. 4, two first lead-out rods 122 are fixed by welding. It can be understood that, considering that one end of the two first lead-out rods 122 connected to the heating section 121 is spaced apart, one end of the two first lead-out rods 122 away from the heating section 121 can be bent in the opposite direction, so that the two first lead-out rods 121 are brought into contact and then fixed by welding. In an embodiment, resistance welding or argon arc welding can be used.

[0045] In an embodiment of the present invention, as shown in FIG. 5, two first lead-out rods 122 are electrically interconnected through the electrical connector 13. In an embodiment, the electrical connector 13 can be a metal conductive member or a non-metallic conductive member. In practical applications, considering the convenience and reliability of connection, a metal conductive member is selected as the electrical connector 13. Metal usually has higher strength and hardness and is able to withstand certain mechanical stress, which ensures the firmness and stability of the connection. Generally, the electrical connector 13 is made of cast iron. The electrical connector 3 can be connected to the two first lead-out rods 122 by welding, screwing or winding. In practical applications, considering processing convenience and reliability, the two first lead-out rods 122 are fixed to the electrical connector 13 by welding. In an embodiment, resistance welding or argon arc welding can be used.

[0046] In an embodiment of the present invention, as shown in FIG. 2, two first lead-out rods 122 are integrally bent and connected. In this embodiment, the two first lead-out rods 122 are configured as an integrated structure, so there is no need for an additional process of electrically connecting the two first lead-out rods 122, further simplifying the processing technology. In practical applications, one conductor can be bent to form two first lead-out rods 122, and ends of the two first lead-out rods 122 away from the bends are connected to the two heating sections 121 respectively.

[0047] It should be noted that in actual application, the electrical connection method of the two first lead-out rods 122 may not be limited to the above-mentioned embodiments, and may also adopt other embodiments, which are not limited here.

[0048] In an embodiment of the present invention, as shown in FIG. 2, FIG. 4 and FIG. 5, the heating tube 1 also comprises a first insulation plug 151 provided at the first end of the tube body 11 and blocking an opening. The first insulation plug 151 wraps the electrical connection parts of the two first lead-out rods 122.

[0049] It can be understood that in actual application, the tube body 11 is filled with electric insulation and heat conduction material 16 (such as magnesium oxide powder, etc.), and the first insulation plug 151 in this embodiment serves to seal the opening of the first end of the tube body 11 to prevent the electric insulation and heat conduction material 16 (such as magnesium oxide powder, etc.) inside the tube body 11 from leaking.

[0050] In this embodiment, by wrapping the first insulation plug 151 around the electrical connection parts of the two first lead-out rods 122, the two first lead-out rods 122 will not be exposed or extend from the pipe body 11, thereby ensuring the insulation effect at the first end of the tube body 11. When the heating tube 1 is used in the heater sleeve 2 of a dry heater or in the inner tank of a water heater, no conductive leakage fault will occur.

[0051] In addition, this embodiment directly uses the first insulation plug 151 that seals the opening of the tube body 11 to insulate the two first lead-out rods 122 without the need to add an additional insulation structure to wrap the two first lead-out rods 122, which saves material costs while simplifying the processing technology.

[0052] It can be understood that the first insulation plug 151 can be completely provided inside the tube body 11, or can be partially provided inside the tube body 11 and partially provided outside the tube body 11, as long as it can seal the opening of the tube body 11 and wrap the two first lead-out rods 122. As an example, taking into account factors such as the difficulty of the processing process and cost, the first insulation plug 151 is provided inside the tube body 11 in this embodiment. During processing, the first insulation plug 151 can be made of hot melt material such as glass. After the heating element 12 and the electric insulation and heat conduction material 16 are provided in the tube body 11, the hot melt material is filled into the first end, and then the first insulation plug 151 is formed by high-temperature heat melting. At the same time, the first insulation plug 151 fixes the two first lead-out rods 122.

[0053] Further, as shown in FIG. 2, FIG. 4 and FIG. 5, the end surface of the first insulation plug 151 away from the heating element 12 is flush with the end surface of the first end of the tube body 11. Such arrangement makes the end surface of the first end of the heating tube 1 flush, which makes it easier to control the length and size of the heating tube 1. When the heating tube 1 is used in the heater sleeve 2, the gap between the first end of the heating tube 1 and the inner wall of the heater sleeve 2 is easier to control, thereby improving the size matching accuracy of the heating tube 1 and the heater sleeve 2.

[0054] In an embodiment of the present invention, as shown in FIG. 3, the heating tube 1 also comprises a second insulation plug 152 provided at the second end of the tube body 11 and blocking the opening. The second insulation plug 152, the first insulation plug 151 and the tube body 11 are enclosed to form a seal cavity. The two heating sections 121 are provided in the seal cavity, and the two second lead-out rods 123 pass through the second insulation plug 152.

[0055] In this embodiment, the second insulation plug 152 serves to seal the opening at the second end of the tube body 11 to prevent the electric insulation and heat conduction material 16 (such as magnesium oxide powder, etc.) from getting wet and prevent the electric insulation and heat conduction material 16 inside the tube body 11 from leakage. At the same time, the second insulation plug 152 also plays a role of supporting and fixing the two second lead-out rods 123.

[0056] Specifically, as shown in FIG. 3, the second insulation plug 152 is provided with two positioning holes 1521 spaced apart, and the two second lead-out rods 123 respectively pass through the two positioning holes 1521 at the second end.

[0057] It can be understood that the first insulation plug 151 at the first end is used to fix the two first lead-out rods 122, and the two positioning holes 1521 at the second end are used to fix the two second lead-out rods 123, so that the two heating sections 121 can be positioned to avoid displacement of the two heating sections 121 and ensure safety. In this embodiment, the two positioning holes 1521 are spaced apart so that the two heating sections 121 can be spaced apart, thereby ensuring the gap between the two heating sections 121 and preventing the two heating sections 121 from contacting each other and causing safety hazards.

[0058] Further, as shown in FIG. 3, the positioning hole 1521 and the corresponding heating section 121 are coaxially arranged. In an embodiment, the two positioning holes 1521 are arranged in parallel, so that the two heating sections 121 are arranged in parallel to prevent the two heating sections 121 from contacting each other.

[0059] In an embodiment, the positioning hole 1521 has an interference fit with the second lead-out rod 123 to enhance the sealing performance of the tube body 11.

[0060] It can be understood that the second insulation plug 152 can be completely provided inside the tube body 11, or can be partially provided inside the tube body 11 and partially provided outside the tube body 11, as long as it can block the opening of the tube body 11. As an example, taking into account factors such as the difficulty of the processing process and cost, the second insulation plug 152 is provided inside the tube body 11 in this embodiment. During processing, the second insulation plug 152 can be made of hot melt material such as glass. After the heating element 12 and the electric insulation and heat conduction material 16 are provided in the tube body 11, the hot melt material is filled into the second end, and then the second insulation plug 152 is formed by high-temperature heat melting. At the same time, the second insulation plug 152 fixes the two second lead-out rods 122.

[0061] Further, as shown in FIG. 3, the end surface of the second insulation plug 152 away from the first end is flush with the end surface of the second end of the tube body 11.

[0062] It can be understood that in practical applications, in order to ensure the electrical safety of the two terminals of the heating tube 1, insulation wrappers can be provided at the two second lead-out rods 123 extending out of the tube body 11. In this embodiment, the end surface of the second insulation plug 152 away from the first end is flush with the end surface of the second end of the tube body 11, so that the insulation wrapper can be connected to the second insulation plug 152 and the tube body 11 at the same time, and the insulation effect at the second end of the heating tube 1 can be further improved.

[0063] Furthermore, in order to ensure the safety of wiring, it is necessary to increase the creepage distance of the two second lead-out rods 123 as much as possible to prevent short circuit. During application, the distance between the two second lead-out rods 123 gradually increases in a direction away from the tube body 11. In an embodiment, the two second lead-out rods 123 generally form a "V"-shaped structure.

[0064] In an embodiment of the present invention, as shown in FIG. 1, the seal cavity is filled with electric insulation and heat conduction material 16, and the electric insulation and heat conduction material 16 isolates the two heating elements 12 and isolates the heating element 12 from the wall of the tube body 11.

[0065] The electric insulation and heat conduction material 16 can conduct the heat of the heating section 121 to the wall of the tube body 11, which is conducive to transferring the heat of the heating section 121. Furthermore, the electric insulation and heat conduction material 16 can isolate the two heating sections 121 to prevent potential safety hazards caused by the two heating sections 121 contacting each other. At the same time, the electric insulation and heat conduction material 16 can isolate the heating element 12 and the inner wall of the tube body 11 to prevent the heating element 12 from contacting the inner wall of the tube body 11 and causing electric leakage. Generally, the electric insulation and heat conduction material 16 is magnesium oxide powder. The magnesium oxide powder has good insulation properties and thermal conductivity, can effectively isolate the current inside the heating tube 1, and transfer the heat of the resistance wire to the tube body 11 in time, which plays the role of electric insulation and heat conduction. Powdered magnesium oxide powder can form a stable support structure in the heating tube 1, so that the heating section 121 of the heating tube 1 is well fixed and supported. This helps to maintain the relative position between the two heating sections 121 and prevent accidental damage to the heating section 121 due to vibration or displacement.

[0066] It can be understood that compared with the heating tube 1 of the related art, the heating tube 1 in the embodiment of the present invention simplifies the processing process and does not require folding, hydraulic molding and other processes. The design of the straight tube facilitates the addition of magnesium oxide powder, so that the filling density of the internal magnesium oxide powder is high, and the heat of the resistance wire can be conducted outward in time, reducing the impact of high temperature environment on the resistance wire and ensuring the life of the resistance wire.

[0067] The present invention also proposes a dry heater, as shown in FIG. 1, FIG. 7 and FIG. 8, the dry heater comprises a heater sleeve 2, an installation base 3 and a heating tube 1. The specific structure of the heating tube 1 refers to the above embodiments. Since this dry heater adopts all the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here. One end of the heater sleeve 2 is closed and the other end of the heater sleeve 2 is open. The installation base 3 is connected to the open end of the heater sleeve 2 and is open corresponding to the position of the heater sleeve 2.The heating tube 1 is provided in the heater sleeve 2, and the terminal 123 of the heating tube 1 is provided outside the heater sleeve 2.

[0068] In actual application, the closed end of the heater sleeve 2 extends into the inner tank 4 of the water heater, and the installation base 3 is installed at the aperture 41 of the inner tank 4, so that the heater sleeve 2 can be fixed inside the inner tank 4. The heating tube 1 is installed in the heater sleeve 2, and the water in the inner tank 4 is heated through the heater sleeve 2. If the dry heater fails, there is no need to disassemble the installation base or drain the water in the inner tank 4, and the heating tube 1 is directly removed from the heater sleeve 2. The disassembly and installation are very simple.

[0069] In this embodiment, the tube body 11 of the heating tube 1 does not need to be folded in half using oil pressure and other processes, so the tube body 11 can be processed with higher precision. The outer diameter of the heating tube 1 can be processed by a multi-roller tube shrinking machine and can be controlled within the range of ±0.1mm, which greatly reduces the gap between the heating tube 1 and the inner wall of the heater sleeve 2 and can ensure that the heat of the heating tube 1 is transferred to the heater sleeve 2 in time and conducts heat exchange with the water, ensuring that the life of the heating tube 1.

[0070] The present invention also proposes a water heater, as shown in FIG. 8, the water heater comprises an inner tank 4 and a dry heater. The specific structure of the dry heater refers to the above embodiments. Since this water heater adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated again. The closed end of the heater sleeve 2 extends into the inner tank 4, and the installation base 3 is fixed to the aperture 41 of the inner tank 4.

[0071] The inner tank 4 has a water inlet pipe 51 and a water outlet pipe 52. The water inlet pipe 51 is used to feed cold water into the inner tank 4, and the water outlet pipe 52 is used to discharge hot water from the inner tank 4. The inner tank 4 is provided with the aperture 41. By fixing the installation base 3 to the aperture 41, the heater sleeve 2 is fixed inside the inner tank 4. The heating tube 1 is installed in the heater sleeve 2, and the water in the inner tank 4 is heated through the heater sleeve 2. When the heating tube 1 fails, there is no need to disassemble the installation base 3 or drain the water in the inner tank 4. The heating tube 1 can be directly removed. The disassembly and installation are very simple.

[0072] The above are only some embodiments of the present invention, and are not intended to limit the scope of the present invention. Under the technical concept of the present invention, equivalent structural transformations made using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are comprised in the scope of the present invention.

Examples

Embodiment Construction

[0028]The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some rather than all of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of the present invention.

[0029]It should be noted that if there are directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention, the directional indications are only used to explain the relative position relationship, movement conditions, etc. between the components in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0030]At the same time, the meaning of "and / or" in the text comprises three parallel solutions. Taking "A and / or B" as an examp...

TECHNICAL FIELD

[0001] The present invention relates to the technical field of water heaters, and in particular to a heating tube, a dry heater and a water heater.BACKGROUND

[0002] Dry heaters are used as heating elements in storage-type electric water heaters. Dry heaters generally have a heating tube and a heater sleeve. The heater sleeve is fixed inside the inner tank, and the heating tube is provided in the heater sleeve. When the heating tube is working, the heating tube is energized to convert electrical energy into thermal energy, and the heat is exchanged with the water in the inner tank through the heater sleeve, thereby heating the water in the inner tank.

[0003] The heating tube of the existing dry heater needs to be folded in half, hydraulically formed and other processes during the processing. Since a heating wire is inserted through the heating tube and the heating tube is filled with magnesium oxide powder, during the folding and hydraulic forming process, external force squeezes the pipe material of the heating tube and the magnesium oxide powder in the heating tube, which will affect the heating tube. The resistance wire causes mechanical damage, which can easily cause premature damage to the resistance wire during use.SUMMARY

[0004] The main purpose of the present invention is to propose a heating tube, a dry heater and a water heater, aiming to simplify processing and reduce the risk of wire breakage.

[0005] In order to achieve the above purpose, the heating tube proposed in the present invention comprises: a tube body and two heating elements.

[0006] In an embodiment of the present invention, the tube body is provided with a first end and a second end opposite to the first end.

[0007] In an embodiment of the present invention, two heating elements are arranged side by side in the tube body, and each heating element comprises a heating section, a first lead-out rod and a second lead-out rod provided at two opposite ends of the heating section.

[0008] In an embodiment of the present invention, two first lead-out rods are electrically interconnected inside the first end, and two second lead-out rods extend from respective second ends to form two terminals.

[0009] In an embodiment of the present invention, the heat tube further comprises a first insulation plug provided at the first end of the tube body and blocking an opening of the tube body.

[0010] In an embodiment of the present invention, the first insulation plug is configured to wrap an electrical connection part of the two first lead-out rods.

[0011] In an embodiment of the present invention, the first insulation plug is provided inside the tube body.

[0012] In an embodiment of the present invention, an end surface of the first insulation plug away from the heating element is flush with an end surface of the first end of the tube body.

[0013] In an embodiment of the present invention, the two first lead-out rods are fixed by welding.

[0014] In an embodiment of the present invention, the two first lead-out rods are electrically interconnected through an electrical connector.

[0015] In an embodiment of the present invention, the two first lead-out rods are of an integrally bent part.

[0016] In an embodiment of the present invention, the heating section is a resistance wire, the resistance wire is arranged in a spiral shape and is sleeved at an end of the first lead-out rod.

[0017] In an embodiment of the present invention, the heating tube further comprises a second insulation plug provided at the second end of the tube body and blocking an opening of the tube body, the second insulation plug, the first insulation plug and the tube body are enclosed to form a seal cavity, the two heating sections are provided in the seal cavity, and the two second lead-out rods are arranged to pass through the second insulation plug.

[0018] In an embodiment of the present invention, the second insulation plug is provided inside the second end of the tube body, and an end surface of the second insulation plug away from the first end is flush with an end surface of the second end of the tube body.

[0019] In an embodiment of the present invention, the seal cavity is filled with electric insulation and heat conduction material, the electric insulation and heat conduction material is configured to isolate the two heating elements and isolate the heating element from a wall of the tube body.

[0020] In an embodiment of the present invention, the tube body is an electric insulation and heat conduction member.

[0021] In order to achieve the above purpose, the present invention also provides a dry heater, comprising: a heater sleeve with one end closed and the other end open; an installation base connected to an open end of the heater sleeve and open at a position corresponding to the heater sleeve; and the heating tube as described above, the heating tube is provided in the heater sleeve, and a terminal of the heating tube is provided outside the heater sleeve.

[0022] In order to achieve the above purpose, the present invention also provides a water heater, comprising an inner tank and the heating tube as described above, and the heating tube is suitable for heating water in the inner tank.

[0023] In order to achieve the above purpose, the present invention also provides a water heater, comprising the dry heater as described above and an inner tank, a closed end of a heater sleeve is configured to extend into the inner tank, and an installation base is fixed to an aperture of the inner tank.

[0024] In the heating tube of the technical solution of the present invention, two heating elements are arranged side by side in the tube body. The heating element comprises a heating section, a first lead-out rod and a second lead-out rod respectively provided at two opposite ends of the heating section. The two first lead-out rods are electrically interconnected inside the first end of the tube body, and the two second lead-out rods extend from respective second ends of the tube body to form two terminals for electrical connection with the power supply outside the tube body, to realize the normal heating function of the two heating elements in the tube body. In this embodiment, by extending the two second lead-out rods of the heating element from the same end of the tube body, there is no need to fold the tube body in half using hydraulic pressure, which simplifies the processing technology and reduces the mechanical damage to the tube body and the heating element. At the same time, it is convenient to control the outer diameter of the tube body, and the processing accuracy is higher, which greatly reduces the gap between the heating tube and the inner wall of the heater sleeve, ensures that the heat of the heating tube is transferred to the sleeve in time and heat exchanges with water, to ensure the life of the heating tube. In addition, by electrically connecting the two first lead-out rods inside the first end of the tube body, there is no need to additionally consider the insulation problem of the conductor being exposed or extending to the outside of the tube body, further simplifying the processing process and improving production efficiency.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly describe the embodiments of the present invention or the technical solutions in the related art, accompanying drawings needed to be used in the description of the embodiments or the related art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative efforts. FIG. 1 is a schematic structural view of a heating tube according to an embodiment of the present invention. FIG. 2 is a partial enlarged view at portion A in FIG. 1. FIG. 3 is a partial enlarged view at portion B in FIG. 1. FIG. 4 is a schematic structural view of a case in which two first lead-out rods are fixed by welding according to an embodiment of the present invention. FIG. 5 is a schematic structural view of a case in which two first lead-out rods are fixed through an electrical connector according to an embodiment of the present invention. FIG. 6 is a schematic structural view of a heating element according to an embodiment of the present invention. FIG. 7 is a schematic structural view of a heating sleeve and an installation base according to an embodiment of the present invention. FIG. 8 is a schematic structural view of a water heater according to an embodiment of the present invention. Description of reference signs

[0026] reference signnamereference signname1heating tube1521positioning hole11tube body16electric insulation and heat conduction material12heating element2heater sleeve121heating section3installation base122first lead-out rod4innertank123second lead-out rod41aperture13electrical connector51water inlet pipe151first insulation plug52water outlet pipe152second insulation plug

[0027] The realization of the purpose, functional features and advantages of the present invention will be further described in conjunction with the embodiments, with reference to the accompanying drawings.DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some rather than all of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of the present invention.

[0029] It should be noted that if there are directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention, the directional indications are only used to explain the relative position relationship, movement conditions, etc. between the components in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0030] At the same time, the meaning of "and / or" in the text comprises three parallel solutions. Taking "A and / or B" as an example, it comprises solution A, or solution B, or a solution that A and B satisfy at the same time.

[0031] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying its relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first" and "second" may explicitly or implicitly comprise at least one of these features. In addition, the technical solutions in the various embodiments can be combined with each other, but it must be based on what a person of ordinary skill in the art can implement. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such a combination of technical solutions does not exist, nor is it within the scope of the present invention.

[0032] The heating tube of the existing dry heater needs to be integrally folded in half, hydraulic forming and other processes during the processing process. It is processed from a long straight round tube into a long straight oval tube body after being folded in half. Since a heating wire is inserted through the heating tube and the heating tube is filled with magnesium oxide powder, during the hydraulic forming process, external force squeezes the tube and the magnesium oxide powder in the heating tube, causing mechanical damage to the resistance wire in the heating tube. It is easy to cause the resistance wire to be damaged in advance during use. The existing technology has the problem that the heating tube has complicated processing technology and the resistance wire is easy to break.

[0033] Based on this, the present invention proposes a heating tube 1, which aims to eliminate the need to bend the electric heating tube as a whole, simplify the processing technology, and reduce the risk of wire breakage. The structure of the heating tube 1 will be described below by way of embodiment.

[0034] In the embodiment of the present invention, as shown in FIG. 1 to FIG. 3 and FIG. 6, the heating tube 1 comprises a tube body 11 and two heating elements 12.

[0035] The tube body 11 has a first end and a second end opposite to the first end. The two heating elements 12 are provided side by side in the tube body 11, and each heating element 12 comprises a heating section 121, a first lead-out rod 122 and a second lead-out rod 123 provided at two opposite ends of the heating section 121. Two first lead-out rods 122 are electrically interconnected inside the first end, and two second lead-out rods 123 respectively extend from respective second ends to form two terminals.

[0036] In this embodiment, the tube body 11 plays the role of installing the heating element 12 and conducting the heat of the heating element 12 away. It can be understood that the insulation between the tube body 11 and the heating element 12 prevents leakage problems caused by electrical conduction between the heating element 12 and the tube body 11. At the same time, the tube body 11 can quickly conduct the heat inside to the outside. In an embodiment, the tube body 11 can be a metal tube or a non-metal tube with good thermal conductivity. The tube body 11 itself can be made of insulating material or non-insulating material. When the tube body 11 is made of non-insulating material, the tube body 11 can be isolated and insulated from the heating element 12 by filling the inside of the tube body 11 with insulating material. In an embodiment, the cross-sectional shape of the tube body 11 can be circular, semicircular, square, triangular or other special shapes. In practical applications, the tube body 11 can be configured as a circular tube for easy molding.

[0037] The two heating elements 12 are arranged side by side in the tube body 11. It can be understood that the two heating elements 12 are arranged at intervals in the tube body 11. The heating element 12 comprises a heating section 121, a first lead-out rod 122 and a second lead-out rod 123. The heating section 121 can be a resistance wire structure with high heating efficiency. The two heating sections 121 are arranged in parallel and spaced apart. The first lead-out rod 122 and the second lead-out rod 123 play the role of wire leads. The first lead-out rods 122 of the two heating elements 12 are electrically interconnected to electrically connect the two heating sections 121. The two second lead-out rods 123 extend from respective second ends of the tube body 11 to form two terminals. The two terminals are a positive terminal and a negative terminal for electrical connection with external power components, to realize the energization and heating function of the two heating sections 121 in the tube body 11. It can be seen from this that the two second lead-out rods 123 of the two heating elements 12 extend from the same end of the tube body 11, and there is no need to fold the tube body 11 in half using hydraulic pressure, which simplifies the process and reduces mechanical damage to the tube body 11 and the resistance wire.

[0038] In addition, this embodiment realizes the electrical conduction function of the two heating sections 121 through the electrical connection of the two first lead-out rods 122. Since the resistance wire is usually made of metal or alloy materials and has a certain elasticity, compared with the solution of directly bending the resistance wire, in this embodiment, the two first lead-out rods 122 can play a role in supporting and limiting the two heating sections 121 to prevent the deformation of the resistance wire from causing uneven heating temperatures, and to prevent the resistance wire from contacting the inner wall of the tube body 11, ensuring electrical safety.

[0039] In practical applications, the first lead-out rod 122 can be a conductive rod, a wire, a conductive sheet, or other conductive structure. It can be understood that the heating section 121 is a resistance wire, and the resistance wire is in a spiral shape. The first lead-out rod 122 has a connection end, and the cross-sectional area of the first lead-out rod 122 gradually decreases from the middle of the first lead-out rod 122 to the connection end so that the connection end forms a tapered shape, which is conducive to the spiral resistance wire being sleeved at the connection end, increasing the contact area between the first lead-out rod 122 and the resistance wire, and ensuring the electrical connection between the first lead-out rod 122 and the resistance wire. In an embodiment, the connection method between the second lead-out rod 123 and the heating section 121 can refer to the connection method between the first lead-out rod 122 and the heating section 121, which will not be repeated here.

[0040] In practical applications, the inside of the tube body 11 is filled with magnesium oxide powder with good thermal conductivity. The compactness of the magnesium oxide powder is related to the thermal conductivity. In the related technology, in order to realize the folding and extrusion of the heating tube 1 as a whole, the magnesium oxide powder filled inside needs to be in a loose state, and the heat transfer efficiency of loose magnesium oxide powder is poor, which causes the internal heating wire to overheat and cause dry burning. In this embodiment, there is no need to bend the heating tube 1 as a whole, and there is no need to reduce the compactness of the magnesium oxide powder. This can ensure the compactness of the magnesium oxide powder and improve the thermal conductivity efficiency, thereby preventing the heating wire from dry burning and overheating, and reducing the occurrence of malfunctions.

[0041] It should be noted that the two first lead-out rods 122 are electrically interconnected inside the first end of the tube body 11, so that the two first lead-out rods 122 will not be exposed or extend outside the tube body 11. Compared with the solution in the related art that the two first lead-out rods 122 extend to outside of the tube body 11 for electrical connection, the heating tube 1 of this embodiment only needs to undergo a normal sealing process (the sealing itself needs to be insulated), and there is no need to additionally consider the insulation problem of the conductor being exposed or extending outside the tube body 11. In addition, there is no additional issues regarding the connection of the external insulation structure and the temperature resistance of the material, that is, the heating tube 1 of this embodiment has a simpler process and higher production efficiency.

[0042] In the heating tube 1 of the technical solution of the present invention, two heating elements 12 are arranged side by side in the tube body 11. The heating element 12 comprises a heating section 121 and a first lead-out rod 122 and a second lead-out rod 123 respectively provided at both ends of the heating section 121. By electrically connecting the two first lead-out rods 122 inside the first end of the tube body 11, the two second lead-out rods 123 respectively extend out of the second end of the tube body 11 to form two terminals for electrical connection with the power supply outside the tube body 11, to realize the normal heating function of the two heating elements 12 in the tube body 11. In this embodiment, the two second lead-out rods 123 of the heating element 12 extend from the same end of the tube body 11, thereby eliminating the need to fold the tube body 11 in half using hydraulic pressure, simplifying the processing technology, and reducing the mechanical damage to the tube body 11 and the heating element 12. At the same time, it is convenient to control the outer diameter of the tube body 11, and the processing precision is higher, which greatly reduces the gap between the heating tube 1 and the inner wall of the heater sleeve 2, ensuring that the heat of the heating tube 1 is transferred to the sleeve in time and is exchanged with water to ensure the life of the heating tube 1. In addition, by electrically connecting the two first lead-out rods 122 inside the first end of the tube body 11, there is no need to additionally consider the insulation problem of the conductor being exposed or extending to the outside of the tube body 11, further simplifying the processing process and improving production efficiency.

[0043] Furthermore, the electrical connection method of the two first lead-out rods 122 can be determined according to actual conditions.

[0044] In an embodiment of the present invention, as shown in FIG. 4, two first lead-out rods 122 are fixed by welding. It can be understood that, considering that one end of the two first lead-out rods 122 connected to the heating section 121 is spaced apart, one end of the two first lead-out rods 122 away from the heating section 121 can be bent in the opposite direction, so that the two first lead-out rods 121 are brought into contact and then fixed by welding. In an embodiment, resistance welding or argon arc welding can be used.

[0045] In an embodiment of the present invention, as shown in FIG. 5, two first lead-out rods 122 are electrically interconnected through the electrical connector 13. In an embodiment, the electrical connector 13 can be a metal conductive member or a non-metallic conductive member. In practical applications, considering the convenience and reliability of connection, a metal conductive member is selected as the electrical connector 13. Metal usually has higher strength and hardness and is able to withstand certain mechanical stress, which ensures the firmness and stability of the connection. Generally, the electrical connector 13 is made of cast iron. The electrical connector 3 can be connected to the two first lead-out rods 122 by welding, screwing or winding. In practical applications, considering processing convenience and reliability, the two first lead-out rods 122 are fixed to the electrical connector 13 by welding. In an embodiment, resistance welding or argon arc welding can be used.

[0046] In an embodiment of the present invention, as shown in FIG. 2, two first lead-out rods 122 are integrally bent and connected. In this embodiment, the two first lead-out rods 122 are configured as an integrated structure, so there is no need for an additional process of electrically connecting the two first lead-out rods 122, further simplifying the processing technology. In practical applications, one conductor can be bent to form two first lead-out rods 122, and ends of the two first lead-out rods 122 away from the bends are connected to the two heating sections 121 respectively.

[0047] It should be noted that in actual application, the electrical connection method of the two first lead-out rods 122 may not be limited to the above-mentioned embodiments, and may also adopt other embodiments, which are not limited here.

[0048] In an embodiment of the present invention, as shown in FIG. 2, FIG. 4 and FIG. 5, the heating tube 1 also comprises a first insulation plug 151 provided at the first end of the tube body 11 and blocking an opening. The first insulation plug 151 wraps the electrical connection parts of the two first lead-out rods 122.

[0049] It can be understood that in actual application, the tube body 11 is filled with electric insulation and heat conduction material 16 (such as magnesium oxide powder, etc.), and the first insulation plug 151 in this embodiment serves to seal the opening of the first end of the tube body 11 to prevent the electric insulation and heat conduction material 16 (such as magnesium oxide powder, etc.) inside the tube body 11 from leaking.

[0050] In this embodiment, by wrapping the first insulation plug 151 around the electrical connection parts of the two first lead-out rods 122, the two first lead-out rods 122 will not be exposed or extend from the pipe body 11, thereby ensuring the insulation effect at the first end of the tube body 11. When the heating tube 1 is used in the heater sleeve 2 of a dry heater or in the inner tank of a water heater, no conductive leakage fault will occur.

[0051] In addition, this embodiment directly uses the first insulation plug 151 that seals the opening of the tube body 11 to insulate the two first lead-out rods 122 without the need to add an additional insulation structure to wrap the two first lead-out rods 122, which saves material costs while simplifying the processing technology.

[0052] It can be understood that the first insulation plug 151 can be completely provided inside the tube body 11, or can be partially provided inside the tube body 11 and partially provided outside the tube body 11, as long as it can seal the opening of the tube body 11 and wrap the two first lead-out rods 122. As an example, taking into account factors such as the difficulty of the processing process and cost, the first insulation plug 151 is provided inside the tube body 11 in this embodiment. During processing, the first insulation plug 151 can be made of hot melt material such as glass. After the heating element 12 and the electric insulation and heat conduction material 16 are provided in the tube body 11, the hot melt material is filled into the first end, and then the first insulation plug 151 is formed by high-temperature heat melting. At the same time, the first insulation plug 151 fixes the two first lead-out rods 122.

[0053] Further, as shown in FIG. 2, FIG. 4 and FIG. 5, the end surface of the first insulation plug 151 away from the heating element 12 is flush with the end surface of the first end of the tube body 11. Such arrangement makes the end surface of the first end of the heating tube 1 flush, which makes it easier to control the length and size of the heating tube 1. When the heating tube 1 is used in the heater sleeve 2, the gap between the first end of the heating tube 1 and the inner wall of the heater sleeve 2 is easier to control, thereby improving the size matching accuracy of the heating tube 1 and the heater sleeve 2.

[0054] In an embodiment of the present invention, as shown in FIG. 3, the heating tube 1 also comprises a second insulation plug 152 provided at the second end of the tube body 11 and blocking the opening. The second insulation plug 152, the first insulation plug 151 and the tube body 11 are enclosed to form a seal cavity. The two heating sections 121 are provided in the seal cavity, and the two second lead-out rods 123 pass through the second insulation plug 152.

[0055] In this embodiment, the second insulation plug 152 serves to seal the opening at the second end of the tube body 11 to prevent the electric insulation and heat conduction material 16 (such as magnesium oxide powder, etc.) from getting wet and prevent the electric insulation and heat conduction material 16 inside the tube body 11 from leakage. At the same time, the second insulation plug 152 also plays a role of supporting and fixing the two second lead-out rods 123.

[0056] Specifically, as shown in FIG. 3, the second insulation plug 152 is provided with two positioning holes 1521 spaced apart, and the two second lead-out rods 123 respectively pass through the two positioning holes 1521 at the second end.

[0057] It can be understood that the first insulation plug 151 at the first end is used to fix the two first lead-out rods 122, and the two positioning holes 1521 at the second end are used to fix the two second lead-out rods 123, so that the two heating sections 121 can be positioned to avoid displacement of the two heating sections 121 and ensure safety. In this embodiment, the two positioning holes 1521 are spaced apart so that the two heating sections 121 can be spaced apart, thereby ensuring the gap between the two heating sections 121 and preventing the two heating sections 121 from contacting each other and causing safety hazards.

[0058] Further, as shown in FIG. 3, the positioning hole 1521 and the corresponding heating section 121 are coaxially arranged. In an embodiment, the two positioning holes 1521 are arranged in parallel, so that the two heating sections 121 are arranged in parallel to prevent the two heating sections 121 from contacting each other.

[0059] In an embodiment, the positioning hole 1521 has an interference fit with the second lead-out rod 123 to enhance the sealing performance of the tube body 11.

[0060] It can be understood that the second insulation plug 152 can be completely provided inside the tube body 11, or can be partially provided inside the tube body 11 and partially provided outside the tube body 11, as long as it can block the opening of the tube body 11. As an example, taking into account factors such as the difficulty of the processing process and cost, the second insulation plug 152 is provided inside the tube body 11 in this embodiment. During processing, the second insulation plug 152 can be made of hot melt material such as glass. After the heating element 12 and the electric insulation and heat conduction material 16 are provided in the tube body 11, the hot melt material is filled into the second end, and then the second insulation plug 152 is formed by high-temperature heat melting. At the same time, the second insulation plug 152 fixes the two second lead-out rods 122.

[0061] Further, as shown in FIG. 3, the end surface of the second insulation plug 152 away from the first end is flush with the end surface of the second end of the tube body 11.

[0062] It can be understood that in practical applications, in order to ensure the electrical safety of the two terminals of the heating tube 1, insulation wrappers can be provided at the two second lead-out rods 123 extending out of the tube body 11. In this embodiment, the end surface of the second insulation plug 152 away from the first end is flush with the end surface of the second end of the tube body 11, so that the insulation wrapper can be connected to the second insulation plug 152 and the tube body 11 at the same time, and the insulation effect at the second end of the heating tube 1 can be further improved.

[0063] Furthermore, in order to ensure the safety of wiring, it is necessary to increase the creepage distance of the two second lead-out rods 123 as much as possible to prevent short circuit. During application, the distance between the two second lead-out rods 123 gradually increases in a direction away from the tube body 11. In an embodiment, the two second lead-out rods 123 generally form a "V"-shaped structure.

[0064] In an embodiment of the present invention, as shown in FIG. 1, the seal cavity is filled with electric insulation and heat conduction material 16, and the electric insulation and heat conduction material 16 isolates the two heating elements 12 and isolates the heating element 12 from the wall of the tube body 11.

[0065] The electric insulation and heat conduction material 16 can conduct the heat of the heating section 121 to the wall of the tube body 11, which is conducive to transferring the heat of the heating section 121. Furthermore, the electric insulation and heat conduction material 16 can isolate the two heating sections 121 to prevent potential safety hazards caused by the two heating sections 121 contacting each other. At the same time, the electric insulation and heat conduction material 16 can isolate the heating element 12 and the inner wall of the tube body 11 to prevent the heating element 12 from contacting the inner wall of the tube body 11 and causing electric leakage. Generally, the electric insulation and heat conduction material 16 is magnesium oxide powder. The magnesium oxide powder has good insulation properties and thermal conductivity, can effectively isolate the current inside the heating tube 1, and transfer the heat of the resistance wire to the tube body 11 in time, which plays the role of electric insulation and heat conduction. Powdered magnesium oxide powder can form a stable support structure in the heating tube 1, so that the heating section 121 of the heating tube 1 is well fixed and supported. This helps to maintain the relative position between the two heating sections 121 and prevent accidental damage to the heating section 121 due to vibration or displacement.

[0066] It can be understood that compared with the heating tube 1 of the related art, the heating tube 1 in the embodiment of the present invention simplifies the processing process and does not require folding, hydraulic molding and other processes. The design of the straight tube facilitates the addition of magnesium oxide powder, so that the filling density of the internal magnesium oxide powder is high, and the heat of the resistance wire can be conducted outward in time, reducing the impact of high temperature environment on the resistance wire and ensuring the life of the resistance wire.

[0067] The present invention also proposes a dry heater, as shown in FIG. 1, FIG. 7 and FIG. 8, the dry heater comprises a heater sleeve 2, an installation base 3 and a heating tube 1. The specific structure of the heating tube 1 refers to the above embodiments. Since this dry heater adopts all the technical solutions of the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here. One end of the heater sleeve 2 is closed and the other end of the heater sleeve 2 is open. The installation base 3 is connected to the open end of the heater sleeve 2 and is open corresponding to the position of the heater sleeve 2.The heating tube 1 is provided in the heater sleeve 2, and the terminal 123 of the heating tube 1 is provided outside the heater sleeve 2.

[0068] In actual application, the closed end of the heater sleeve 2 extends into the inner tank 4 of the water heater, and the installation base 3 is installed at the aperture 41 of the inner tank 4, so that the heater sleeve 2 can be fixed inside the inner tank 4. The heating tube 1 is installed in the heater sleeve 2, and the water in the inner tank 4 is heated through the heater sleeve 2. If the dry heater fails, there is no need to disassemble the installation base or drain the water in the inner tank 4, and the heating tube 1 is directly removed from the heater sleeve 2. The disassembly and installation are very simple.

[0069] In this embodiment, the tube body 11 of the heating tube 1 does not need to be folded in half using oil pressure and other processes, so the tube body 11 can be processed with higher precision. The outer diameter of the heating tube 1 can be processed by a multi-roller tube shrinking machine and can be controlled within the range of ±0.1mm, which greatly reduces the gap between the heating tube 1 and the inner wall of the heater sleeve 2 and can ensure that the heat of the heating tube 1 is transferred to the heater sleeve 2 in time and conducts heat exchange with the water, ensuring that the life of the heating tube 1.

[0070] The present invention also proposes a water heater, as shown in FIG. 8, the water heater comprises an inner tank 4 and a dry heater. The specific structure of the dry heater refers to the above embodiments. Since this water heater adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated again. The closed end of the heater sleeve 2 extends into the inner tank 4, and the installation base 3 is fixed to the aperture 41 of the inner tank 4.

[0071] The inner tank 4 has a water inlet pipe 51 and a water outlet pipe 52. The water inlet pipe 51 is used to feed cold water into the inner tank 4, and the water outlet pipe 52 is used to discharge hot water from the inner tank 4. The inner tank 4 is provided with the aperture 41. By fixing the installation base 3 to the aperture 41, the heater sleeve 2 is fixed inside the inner tank 4. The heating tube 1 is installed in the heater sleeve 2, and the water in the inner tank 4 is heated through the heater sleeve 2. When the heating tube 1 fails, there is no need to disassemble the installation base 3 or drain the water in the inner tank 4. The heating tube 1 can be directly removed. The disassembly and installation are very simple.

[0072] The above are only some embodiments of the present invention, and are not intended to limit the scope of the present invention. Under the technical concept of the present invention, equivalent structural transformations made using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields, are comprised in the scope of the present invention.

Examples

Embodiment Construction

[0028]The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some rather than all of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of the present invention.

[0029]It should be noted that if there are directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention, the directional indications are only used to explain the relative position relationship, movement conditions, etc. between the components in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0030]At the same time, the meaning of "and / or" in the text comprises three parallel solutions. Taking "A and / or B" as an examp...

Claims

1. A heating tube (1), characterized by comprising: a tube body (11) provided with a first end and a second end opposite to the first end; and two heating elements (12) arranged side by side in the tube body (11), each heating element (12) comprising a heating section (121), a first lead-out rod (122) and a second lead-out rod (123) respectively provided at two opposite ends of the heating section (121), wherein two first lead-out rods (122) are electrically interconnected inside the first end, and wherein two second lead-out rods (123) extend from respective second ends to form two terminals.

2. The heating tube (1) according to claim 1, further comprising a first insulation plug (151) provided at the first end of the tube body (11) and blocking an opening of the tube body (11), wherein the first insulation plug (151) is configured to wrap an electrical connection part of the two first lead-out rods (122).

3. The heating tube (1) according to claim 2, wherein the first insulation plug (151) is provided inside the tube body (11).

4. The heating tube (1) according to claim 2 or 3, wherein an end surface of the first insulation plug (151) away from the heating element (12) is flush with an end surface of the first end of the tube body (11).

5. The heating tube (1) according to any one of claims 1 to 4, wherein the two first lead-out rods (122) are fixed by welding, or wherein the two first lead-out rods (122) are electrically interconnected through an electrical connector (13), or wherein the two first lead-out rods (122) are of an integrally bent part.

6. The heating tube (1) according to any one of claims 1 to 5, wherein the heating section (121) is a resistance wire, wherein the resistance wire is arranged in a spiral shape and is sleeved at an end of the first lead-out rod (122).

7. The heating tube (1) according to any one of claims 2 to 6, further comprising a second insulation plug (152) provided at the second end of the tube body (11) and blocking an opening of the tube body (11), wherein the second insulation plug (152), the first insulation plug (151) and the tube body (11) are enclosed to form a seal cavity, wherein the two heating sections (121) are provided in the seal cavity, and wherein the two second lead-out rods (123) are arranged to pass through the second insulation plug (152).

8. The heating tube (1) according to claim 7, wherein the second insulation plug (152) is provided inside the second end of the tube body (11), and wherein an end surface of the second insulation plug (152) away from the first end is flush with an end surface of the second end of the tube body (11).

9. The heating tube (1) according to claim 7 or 8, wherein the seal cavity is filled with electric insulation and heat conduction material (16) configured to isolate the two heating elements (12) and isolate the heating element (12) from a wall of the tube body (11), and / or wherein the tube body (11) is an electric insulation and heat conduction member.

10. A dry heater, characterized by comprising: a heater sleeve (2) with an end closed and the other end open; an installation base (3) connected to an open end of the heater sleeve (2) and being open at a position corresponding to the heater sleeve (2); and a heating tube (1) according to any one of claims 1 to 9, wherein the heating tube (1) is provided in the heater sleeve (2), and wherein a terminal of the heating tube (1) is provided outside the heater sleeve (2).

11. A water heater, characterized by comprising: an inner tank (4) and a heating tube (1) according to any one of claims 1 to 9, wherein the heating tube (1) is suitable for heating water in the inner tank (4); or a dry heater according to claim 10 and an inner tank (4), wherein a closed end of a heater sleeve (2) is configured to extend into the inner tank (4), and wherein an installation base (3) is fixed to an aperture (41) of the inner tank (4).

Images