Heating pipe, dry heater and water heater

Abstract

The utility model discloses a heating pipe, a dry type heater and a water heater, and relates to the technical field of water heaters. Wherein the heating pipe comprises a pipe body, two lead-out rods and a resistance wire, and the pipe body is provided with a first end and a second end which are axially opposite to each other; the two lead-out rods are arranged in the tube body side by side and extend out of the second end to form two wiring ends; the resistance wire is arranged in the tube body and extends along the axial direction of the tube body; and two axial ends of the resistance wire are electrically connected with the two lead-out rods respectively. According to the technical scheme, folding oil pressure operation does not need to be carried out on the pipe body, the processing technology of the heating pipe is simplified, and the wire breaking risk is reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to water heater technical field, especially a kind of heating pipe, dry heater and water heater. BACKGROUND

[0002] Dry heater is applied to water storage type electric water heater as heating element. Dry heater generally has heating pipe and heater sleeve, heater sleeve is fixed inside inner container, and heating pipe is placed into heater sleeve. When heating pipe works, heating pipe converts electric energy into heat energy by electrification, and heat is exchanged with water in inner container through heater sleeve, to heat water in inner container.

[0003] The heating pipe in the related art needs to pass through processes such as folding and oil pressure forming during processing. Since heating wire is arranged in the heating pipe, and magnesium oxide powder is filled in the heating pipe, the external force extruding the pipe material of the heating pipe and the magnesium oxide powder in the heating pipe during folding and oil pressure forming can mechanically damage the resistance wire in the heating pipe, and easily cause the resistance wire to be damaged in advance during use. SUMMARY

[0004] The main purpose of the utility model is to provide a kind of heating pipe, to simplify processing, reduce the risk of wire breakage.

[0005] To achieve the above purpose, the heating pipe provided by the utility model comprises:

[0006] Pipe body, with axially opposite first end and second end;

[0007] Two lead-out rods are arranged side by side in the pipe body, and two lead-out rods extend from the second end to form two wiring ends;And

[0008] Resistance wire is arranged in the pipe body and extends along the axial direction of the pipe body;The axial ends of the resistance wire are electrically connected to the two lead-out rods respectively.

[0009] In an embodiment of the present application, the resistance wire is electrically connected to one of the lead-out rods at a position close to the first end, and the resistance wire is electrically connected to the other lead-out rod at a position close to the second end.

[0010] In an embodiment of the present application, the two lead-out rods include a first lead-out rod and a second lead-out rod, and the length of the first lead-out rod is greater than the length of the second lead-out rod.

[0011] The axial ends of the resistance wire are electrically connected to the end of the first lead-out rod and the end of the second lead-out rod respectively.

[0012] In an embodiment of the present application, the electrically resistive wire is insulated and wound around the periphery of the portion of the first lead rod that is longer than the second lead rod.

[0013] In an embodiment of the present application, the heating tube comprises at least two groups of electrically resistive wires arranged along the axial direction of the tube body, and the at least two groups of electrically resistive wires are connected in parallel through the two lead rods.

[0014] In an embodiment of the present application, the heating tube further comprises a sealing cover arranged at the tube opening of the first end, and the sealing cover is fixedly connected with the tube body to block the tube opening of the first end.

[0015] In an embodiment of the present application, one end of the sealing cover away from the second end does not protrude from the tube opening end surface of the first end.

[0016] In an embodiment of the present application, the heating tube further comprises an insulating plug arranged at the second end of the tube body and blocking the tube opening, and the insulating plug, the sealing cover and the tube body enclose a sealed cavity, the electrically resistive wires are located in the sealed cavity, and the two wire terminals are arranged through the insulating plug.

[0017] In an embodiment of the present application, the tube body is filled with an insulating and heat-conducting material, and the insulating and heat-conducting material separates the two lead rods, the electrically resistive wires and the tube wall of the tube body.

[0018] In an embodiment of the present application, the tube body is an insulating and heat-conducting member.

[0019] To achieve the above object, the present application further provides a dry-type heater, comprising:

[0020] a heater sleeve with one end closed and the other end open;

[0021] a mounting seat connected to the open end of the heater sleeve and corresponding to the position of the heater sleeve; and

[0022] the above-mentioned heating tube is arranged in the heater sleeve, and the wire terminals of the heating tube are arranged outside the heater sleeve.

[0023] To achieve the above object, the present application further provides a water heater, comprising the above-mentioned dry-type heater and an inner container, the closed end of the heater sleeve extends into the inner container, and the mounting seat is fixed to the container opening of the inner container.

[0024] In this invention, the heating tube contains a resistance wire extending axially within the tube body. By electrically connecting both ends of the resistance wire to two lead-out rods, each extending from the second end of the tube body, two terminals are formed for electrical connection to an external power source. This enables the resistance wire to generate heat normally within the tube body. This embodiment eliminates the need for hydraulic pressure folding of the tube body by extending the two lead-out rods from the same end, simplifying the manufacturing process and reducing mechanical damage to the tube body and resistance wire. Furthermore, it facilitates control of the tube's outer diameter, ensuring high processing precision and significantly reducing the gap between the heating tube and the inner wall of the heater sleeve. This guarantees timely heat transfer from the heating tube to the sleeve and heat exchange with the water, thus extending the heating tube's lifespan. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of an embodiment of the heating tube of this utility model;

[0027] Figure 2 for Figure 1 A schematic diagram of the resistance wire and two lead-out rods in the embodiment;

[0028] Figure 3 This is a schematic diagram of another embodiment of the heating tube of this utility model;

[0029] Figure 4 for Figure 3 A schematic diagram of the resistance wire and two lead-out rods in the embodiment;

[0030] Figure 5 This is a schematic diagram of the heater sleeve and mounting base in an embodiment of the present invention;

[0031] Figure 6 A schematic diagram of the structure of an embodiment of the water heater provided by this utility model.

[0032] Explanation of icon numbers:

[0033]

[0034]

[0035] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0037] It should be noted that if the embodiments of the present application involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative positional relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications will also change accordingly.

[0038] Meanwhile, "and / or" or "and / or" appearing throughout the text means that it includes three schemes, for example, "A and / or B" includes A scheme, or B scheme, or A and B schemes are satisfied at the same time.

[0039] In addition, if the embodiments of the present application involve "first", "second" and the like, the "first", "second" and the like are only for description purposes, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the scope of protection required by the present application.

[0040] The heating pipe of the existing dry heater needs to be folded in whole, oil pressure formed and the like in the processing process, and is processed into a folded long straight oval pipe body from a long straight circular pipe. Since the heating wire is arranged in the heating pipe, and the magnesium oxide powder is filled in the heating pipe, in the oil pressure forming process, the external force extrudes the pipe material and the magnesium oxide powder in the heating pipe, and mechanically damages the resistance wire in the heating pipe, which is easy to cause the resistance wire to be damaged in advance in the use process. The existing technology has the problems of complex heating pipe processing technology and easy wire breaking of the resistance wire.

[0041] Based on this, the present application provides a heating pipe, which aims to simplify the processing technology and reduce the risk of wire breaking without folding the electric heating pipe in whole. The structure of the present heating pipe will be described in the form of embodiments.

[0042] In the embodiments of the present application, as shown inFigures 1 to 4 As shown, the heating tube 1 includes a tube body 11, two lead rods (131 / 132) and a resistance wire 12. The tube body 11 has a first end 11a and a second end 11b that are axially opposite each other. The two lead rods (131 / 132) are arranged side by side in the tube body 11, and the two lead rods (131 / 132) extend from the second end 11b to form two terminals. The resistance wire 12 is disposed in the tube body 11 and extends along the axial direction of the tube body 11. The two ends of the resistance wire 12 are electrically connected to the two lead rods (131 / 132) respectively.

[0043] In this embodiment, the tube 11 serves to mount the two lead-out rods (131 / 132) and the resistance wire 12, and to conduct the heat from the resistance wire 12 away. It is understood that the tube 11 is insulated from the resistance wire 12 and the lead-out rods (131 / 132) to prevent leakage current between the resistance wire 12, the lead-out rods (131 / 132), and the tube 11. Optionally, the tube 11 can be a metal tube or a non-metal tube with good thermal conductivity. The tube 11 itself can be an insulating material or a non-insulating material. When it is a non-insulating material, insulation can be achieved by filling the inside of the tube 11 with insulating material to isolate it from the resistance wire 12 and the lead-out rods (131 / 132). Optionally, the cross-sectional shape of the tube 11 can be circular, semi-circular, square, triangular, or other irregular shapes. In practical applications, the tube 11 can be set as a circular tube that is easy to form.

[0044] Two lead-out rods (131 / 132) are arranged side-by-side in the tube body 11, each extending from the second end 11b to form two terminals. These terminals are understood to be the positive and negative terminals, respectively, used to electrically connect the second end 11b of the tube body 11 to an external power supply structure. A resistance wire 12 extends axially within the tube body 11, with both ends electrically connected to the two lead-out rods (131 / 132), thus enabling the resistance wire 12 to generate heat. Therefore, since both lead-out rods (131 / 132) for electrically connecting the resistance wire 12 extend from the same end of the tube body 11, there is no need to fold the tube body 11 using hydraulic pressure, simplifying the process and reducing mechanical damage to the tube body 11 and the resistance wire 12. Furthermore, the axial extension of the resistance wire 12 along the tube body 11 increases its length, expands the heating area, and improves the heating efficiency of the heating tube 1.

[0045] In actual application, the pipe body 11 is filled with magnesium oxide powder with good heat conduction performance, and the compactness of the magnesium oxide powder is related to the heat conduction performance, in the related art, in order to realize the overall folding and extruding of the heating pipe 1, the internally filled magnesium oxide powder needs to be in a state of relatively loose compactness, and the heat transfer efficiency of the magnesium oxide powder with relatively loose compactness is poor, which can cause the internal electric heating wire to overheat and dry burning and wire breaking, the embodiment does not need to fold the heating pipe 1 as a whole, and thus the compactness of the magnesium oxide powder does not need to be reduced, so that the compactness of the magnesium oxide powder can be ensured, the heat conduction efficiency is improved, and the electric resistance wire 12 can be prevented from dry burning and overheating, and the fault occurrence is reduced.

[0046] It should be noted that, by electrically connecting the electric resistance wire 12 with the two lead-out rods (131 / 132) in the pipe body 11, compared with the scheme in the related art that the two heating sections are electrically connected by being extended to the outside of the pipe body 11 through two electric connecting members, the heating pipe 1 of the embodiment only needs to perform a normal sealing process, without the need to additionally consider the insulation problem of the exposed or extended electric conductor to the outside of the pipe body 11, and thus there are no additional problems such as connection and material temperature resistance of the external insulation structure, that is, the process of the heating pipe 1 of the embodiment is simpler, and the production efficiency is higher.

[0047] Optionally, the electric resistance wire 12 is welded with the lead-out rods (131 / 132).

[0048] In summary, in the technical scheme of the heating pipe 1, the electric resistance wire 12 extends in the pipe body 11 along the axial direction of the pipe body 11, the axial two ends of the electric resistance wire 12 are electrically connected with the two lead-out rods (131 / 132) respectively, and the two lead-out rods (131 / 132) are extended from the second end 11b of the pipe body 11 to form two wiring ends for electrical connection with the power supply outside the pipe body 11, so that the function of normally electrifying and heating the electric resistance wire 12 in the pipe body 11 can be realized. In the embodiment, the two lead-out rods (131 / 132) are extended from the same end of the pipe body 11, without the need to perform the folding and oil pressure operation on the pipe body 11, so that the machining process is simplified, and the mechanical damage to the pipe body 11 and the electric resistance wire 12 is reduced; meanwhile, the outer diameter of the pipe body 11 is convenient to control, the machining precision is high, the gap between the heating pipe 1 and the inner wall of the heater sleeve 2 is greatly reduced, and the life of the heating pipe 1 can be ensured.

[0049] Please refer to Figure 1 and Figure 2 In an embodiment of the present application, the electric resistance wire 12 is electrically connected with one of the lead-out rods 131 at a position close to the first end 11a, and the electric resistance wire 12 is electrically connected with the other lead-out rod 132 at a position close to the second end 11b.

[0050] In the embodiment, the two axial ends of the resistance wire 12 are arranged at positions close to the first end 11a and the second end 11b of the tube body 11, which can lengthen the resistance wire 12, increase the heating area, and increase the heat exchange area of the heating tube 1.

[0051] Optionally, the resistance wire 12 can be connected with the end of the lead rod (131 / 132), or can be connected with the middle position of the lead rod (131 / 132).

[0052] For example, the two lead rods (131 / 132) include a first lead rod 131 and a second lead rod 132, the length of the first lead rod 131 is greater than the length of the second lead rod 132, and the two axial ends of the resistance wire 12 are respectively electrically connected with the end of the first lead rod 131 and the end of the second lead rod 132.

[0053] In the embodiment, the length of the first lead rod 131 is greater than the length of the second lead rod 132, and the first lead rod 131 extends from the second end 11b to a position close to the first end 11a, and the second lead rod 132 extends from the outside of the second end 11b to a position close to the second end 11b. The two axial ends of the resistance wire 12 are respectively electrically connected with the end of the first lead rod 131 and the end of the second lead rod 132, so that the resistance wire 12 can extend from the position close to the second end 11b to the position close to the first end 11a, lengthen the resistance wire 12, increase the heating area of the resistance wire 12, and further increase the heating area of the heating tube 1.

[0054] Optionally, the two axial ends of the resistance wire 12 are welded with the end of the first lead rod 131 and the end of the second lead rod 132.

[0055] Further, referring to Figure 1 and Figure 2 , the resistance wire 12 is insulated and wound around the periphery of the part of the first lead rod 131 which is longer than the second lead rod 132.

[0056] It can be understood that the resistance wire 12 has a spiral structure, and in the embodiment, the resistance wire 12 is insulated and wound around the periphery of the part of the first lead rod 131 which is longer than the second lead rod 132, which can reduce the diameter of the tube body 11, prevent the resistance wire 12 from contacting and short-circuiting with the first lead rod 131, and increase the structural strength of the resistance wire 12.

[0057] Please refer to Figure 3 and Figure 4In an embodiment of the present application, the heating tube 1 comprises at least two groups of resistance wires 12 arranged in the axial direction of the tube body 11, and the at least two groups of resistance wires 12 are connected in parallel through two lead-out rods (131 / 132).

[0058] In the embodiment, the heating tube 1 comprises two or more groups of resistance wires 12 arranged in the axial direction of the tube body 11 and connected in parallel through two lead-out rods (131 / 132), which can prolong the length of the resistance wires 12, increase the heating area, and improve the heating efficiency.

[0059] It can be understood that the at least two groups of resistance wires 12 are arranged in the axial direction of the tube body 11 from a position close to the first end 11a to a position close to the second end 11b, which can improve the structural strength of the resistance wires 12 and prevent the resistance wires 12 from being broken.

[0060] As an example, the two groups of resistance wires 12, the first lead-out rod 131 with a longer length, and the second lead-out rod 132 with a shorter length are taken as an example, the two ends of the resistance wires 12 close to the first end 11a can be electrically connected to the ends of the first lead-out rod 131 and the second lead-out rod 132 respectively, and the two ends of the resistance wires 12 close to the second end 11b can be electrically connected to the middle position of the first lead-out rod 131 and the position close to the second end 11b of the second lead-out rod 132 respectively.

[0061] Please refer to Figure 1 and Figure 3 In an embodiment of the present application, the tube body 11 is filled with an insulating and heat-conducting material 16, which separates the two lead-out rods (131 / 132), the resistance wires 12, and the tube wall of the tube body 11.

[0062] The insulating and heat-conducting material 16 can conduct the heat of the resistance wires 12 to the tube wall of the tube body 11, and further, the insulating and heat-conducting material 16 can insulate the two lead-out rods (131 / 132), the resistance wires 12, and the inner wall of the tube body 11 to avoid mutual contact and cause safety hazards. Optionally, the insulating and heat-conducting material 16 is magnesium oxide powder, which has good insulation and heat conduction properties, can effectively insulate the current inside the heating tube 1, and timely transfer the heat of the resistance wires 12 to the tube body 11 to play the role of insulation and heat conduction.

[0063] It can be understood that, compared with the prior art heating tube 1, the heating tube 1 of the embodiment of the present application simplifies the processing flow, does not need processes such as folding and oil pressure forming, the straight tube design facilitates the addition of magnesium oxide powder, the filling density of the magnesium oxide powder inside is high, the heat of the resistance wires 12 can be timely conducted outward, the influence of the high-temperature environment on the resistance wires 12 is reduced, and the service life of the resistance wires 12 is guaranteed.

[0064] Referring to Figure 1 and Figure 3 In an embodiment of the present application, the heating tube 1 further comprises a sealing cover 14 arranged at the pipe opening of the first end 11a, the sealing cover 14 is fixedly connected with the tube body 11 to seal the pipe opening of the first end 11a.

[0065] It can be understood that in actual application, the tube body 11 is filled with insulating heat-conducting material 16 (such as magnesium oxide powder, etc.), and the sealing cover 14 in the embodiment plays a role of sealing the pipe opening of the first end 11a of the tube body 11, preventing the insulating heat-conducting material 16 (such as magnesium oxide powder, etc.) inside the tube body 11 from leaking.

[0066] It can be understood that the sealing cover 14 can be completely accommodated in the interior of the tube body 11, or can be partially located in the interior of the tube body 11 and partially located in the exterior of the tube body 11, as long as it can seal the pipe opening of the tube body 11. As an example, considering the difficulty and cost of the processing process, etc., the sealing cover 14 in the embodiment is accommodated in the interior of the tube body 11, and in processing, the sealing cover 14 can be made of a metal material such as stainless steel and is fixed with the tube body 11 by welding. Alternatively, in some other embodiments, the sealing cover 14 can be made of a hot melt material such as glass, and after the electric resistance wire 12, the lead rod (131 / 132) and the insulating heat-conducting material 16 are arranged in the tube body 11, the hot melt material is filled into the first end 11a, and then the hot melt material is formed into the structure of the sealing cover 14 by high-temperature hot melting.

[0067] Further, the end surface of the sealing cover 14 away from the second end 11b does not protrude from the end surface of the first end 11a. In this way, the end surface of the first end 11a of the heating tube 1 is flush, thereby being more convenient for controlling the length dimension of the heating tube 1, and when the heating tube 1 is applied to the heater sleeve 2, the gap between the end of the first end 11a of the heating tube 1 and the inner wall of the heater sleeve 2 is more easily controlled, and the size matching precision of the heating tube 1 and the heater sleeve 2 is improved.

[0068] Referring to Figure 1 and Figure 3 In an embodiment of the present application, the heating tube 1 further comprises an insulating plug 15 arranged at the second end 11b of the tube body 11 and sealing the pipe opening, the insulating plug 15, the sealing cover 14 and the tube body 11 form a sealed cavity, the electric resistance wire 12 is located in the sealed cavity, and the two lead rods (131 / 132) are arranged in the insulating plug 15.

[0069] In the embodiment, the insulating plug 15 plays a role of sealing the pipe opening of the second end 11b of the pipe body 11, avoiding the insulation heat-conducting material 16 (such as magnesium oxide powder) from being damp, and preventing the insulation heat-conducting material 16 inside the pipe body 11 from leaking. Meanwhile, the insulating plug 15 also plays a role of supporting and fixing the two lead-out rods (131 / 132). Specifically, the insulating plug 15 is provided with two spaced apart positioning holes, and the two lead-out rods (131 / 132) are respectively led out from the two positioning holes located at the second end 11b.

[0070] It can be understood that the insulating plug 15 can be completely accommodated in the interior of the pipe body 11, or can be partially located in the interior of the pipe body 11 and partially located in the exterior of the pipe body 11, as long as the pipe opening of the pipe body 11 can be sealed. As an example, considering the difficulty and cost of the processing process, in the embodiment, the insulating plug 15 is accommodated in the interior of the pipe body 11. In the processing, the insulating plug 15 can adopt a hot melt material such as glass. After the resistance wire 12 and the insulation heat-conducting material 16 are arranged in the pipe body 11, the hot melt material is filled into the second end 11b, and then the hot melt material is formed into the structure of the insulating plug 15 through high-temperature hot melting. Meanwhile, the insulating plug 15 fixes the two lead-out rods (131 / 132).

[0071] The utility model discloses still propose a kind of dry heater, such as Figure 5 And Figure 6 The dry heater includes heater sleeve 2, mounting seat 3 and heating pipe 1, and the specific structure of the heating pipe 1 refers to the above embodiment. Since the dry 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 here. The closed end of the heater sleeve 2 is closed, and the other end is open. The mounting seat 3 is connected to the open end of the heater sleeve 2 and is open at the position corresponding to the heater sleeve 2. The heating pipe 1 is arranged in the heater sleeve 2, and the wiring end of the heating pipe 1 is arranged outside the heater sleeve 2.

[0072] In actual application, the closed end of the heater sleeve 2 extends into the inner container 4 of the water heater, and the mounting seat 3 is installed at the container opening 41 of the inner container 4, so that the heater sleeve 2 can be fixed inside the inner container 4. The heating pipe 1 is installed in the heater sleeve 2, and the water in the inner container 4 is heated through the heater sleeve 2. If the dry heater fails, it is not necessary to disassemble the mounting seat 3 or to drain the water in the inner container 4. The heating pipe 1 can be directly disassembled from the heater sleeve 2, and the disassembly and assembly are very simple.

[0073] The pipe body 11 of the heating pipe 1 in the embodiment does not need to be folded and pressed by oil pressure and other processes, so that the machining precision of the pipe body 11 is higher, the outer diameter size of the heating pipe 1 is machined by a multi-roller pipe reducing machine, and can be controlled within a range of ±0.1 mm, so that the gap between the heating pipe 1 and the inner wall size of the heater sleeve 2 is greatly reduced, and the heat of the heating pipe 1 can be ensured to be timely transmitted to the heater sleeve 2 and heat exchanged with water, so that the service life of the heating pipe 1 is ensured.

[0074] The utility model discloses still propose a kind of water heaters, such as Figure 6 , the water heater includes inner bag 4 and dry heater, the specific structure of the dry heater refers to above-mentioned embodiment, since the present water heater has adopted all technical solutions of above-mentioned all embodiments, at least has all beneficial effects brought by the technical solutions of above-mentioned embodiments, here no longer one by one, heater sleeve 2 closed end is inserted into inner bag 4, mounting seat 3 is fixed to the bag mouth 41 of inner bag 4.

[0075] Inner bag 4 has water inlet pipe 51 and outlet pipe 52, water inlet pipe 51 is used to enter cold water to inner bag 4, and outlet pipe 52 is used to export hot water from inner bag 4. Inner bag 4 is equipped with bag mouth 41, by mounting seat 3 is fixed in bag mouth 41, realize heater sleeve 2 is fixed in inner bag 4. Heating pipe 1 is installed in heater sleeve 2, and water in inner bag 4 is heated by heater sleeve 2. When heating pipe 1 fails, mounting seat 3 can not need to be disassembled, and water in inner bag 4 also does not need to be discharged, and heating pipe 1 can be directly disassembled, and disassembly installation is very simple.

[0076] The above-mentioned is only the preferred embodiment of the utility model, and does not limit the patent range of the utility model, and any equivalent structural transformation made under the utility model concept of the utility model, or direct / indirect application in other related technical fields is included in the patent protection range of the utility model.

Claims

1. A heating tube, characterized by, The heating tube comprises: a tube body having axially opposite first and second ends; two lead-out rods arranged side by side in the tube body, the two lead-out rods extending from the second end to form two terminal ends, the two lead-out rods comprising a first lead-out rod and a second lead-out rod, the first lead-out rod being longer than the second lead-out rod; and a resistance wire arranged in the tube body and extending along the axial direction of the tube body, the two axial ends of the resistance wire being electrically connected to the two lead-out rods respectively, and the resistance wire being insulatedly arranged around the portion of the first lead-out rod that is longer than the second lead-out rod.

2. The heating tube of claim 1 wherein, The resistance wire is electrically connected to one of the lead-out rods near the first end, and the resistance wire is electrically connected to the other lead-out rod near the second end.

3. The heating tube of claim 2 wherein, The two axial ends of the resistance wire are electrically connected to the end of the first lead-out rod and the end of the second lead-out rod respectively.

4. The heating tube of claim 1 wherein, The heating tube comprises at least two groups of resistance wires arranged along the axial direction of the tube body at intervals, and the at least two groups of resistance wires are connected in parallel through the two lead-out rods.

5. The heating tube according to any one of claims 1 to 4, wherein The heating tube further comprises a sealing cover arranged at the tube opening of the first end, the sealing cover being fixedly connected to the tube body to block the tube opening of the first end.

6. The heating tube of claim 5 wherein, The end of the sealing cover away from the second end does not protrude from the end face of the tube opening of the first end.

7. The heating tube of claim 5 wherein, The heating tube further comprises an insulating plug arranged at the second end of the tube body and blocking the tube opening, the insulating plug, the sealing cover and the tube body enclosing a sealed cavity, the resistance wire being located in the sealed cavity, and the two terminal ends penetrating the insulating plug.

8. The heating tube according to any one of claims 1 to 4, wherein The tube body is filled with an insulating and heat-conducting material, which separates the two lead-out rods, the resistance wire and the tube wall of the tube body; and / or the tube body is an insulating and heat-conducting member.

9. A dry heater characterized by, The heating tube comprises: a heater sleeve having one closed end and the other open end; a mounting seat connected to the open end of the heater sleeve and corresponding to the position of the heater sleeve; and the heating tube as claimed in any one of claims 1 to 8, the heating tube being arranged in the heater sleeve, and the terminal ends of the heating tube being arranged outside the heater sleeve.

10. A water heater, characterized by The dry heater and the inner container as claimed in claim 9, the closed end of the heater sleeve extending into the inner container, and the mounting seat being fixed to the container opening of the inner container.

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