An electric heater with uniform heating

Abstract

The utility model discloses an even heating's electric heater, it includes casing, heating band and at least two terminal pin subassembly, casing is provided with the accommodation cavity, and heating band is accommodated in the accommodation cavity, heating band includes one or more heating strip, and one or more heating strip multiple left and right alternately bending and winding into heating band, and the contact part of bending of same heating strip or adjacent two heating strips is fixedly connected, and terminal pin subassembly is installed on the casing, and terminal pin subassembly and heating band in the casing electrically connected. Heating strip adopts left and right alternately bending, and bending is several character bend shape, and the several character bend of two heating strips constitutes the rectangle structure, and compared with traditional electric heating band, the evenness is better, and the heat dissipation / heat transfer path is more reasonable, and further reduces the structure, so that it can be used for small space pipeline.

Description

Technical Field

[0001] This utility model relates to the field of electric heating, and in particular to an electric heater that provides uniform heating. Background Technology

[0002] Traditional heating bands have a relatively complex structure, and the materials used are usually quite rigid. Therefore, traditional electric heating bands 91 have internal wave-shaped heat dissipation fins to improve temperature uniformity, such as... Figure 1 As shown, the curvature of the electric heating strip during winding should not be too small. Once the overall diameter of the electric heating strip reaches the limit value of φ150mm, it cannot be reduced further, resulting in a large overall structure that is not suitable for installation in small space pipelines with a diameter of <150mm.

[0003] The original heating strip was usually made by clamping and winding. This process can easily cause scratches and deformation on the surface of the heating strip, leading to its scrapping. It is also very time-consuming. In addition, there is a sickle-shaped bend in the center of the heating strip. Due to the tension of the material, the center of the heating strip is not flat when it is wound, and the layers of heating strip cannot be completely bonded together.

[0004] Therefore, considering the aforementioned technical problems, it is necessary to provide a new technical solution. Utility Model Content

[0005] To at least solve one of the technical problems existing in the prior art, this utility model provides an electric heater for uniform heating. The specific technical solution is as follows:

[0006] This utility model provides an electric heater for uniform heating, which includes a housing, a heating belt and at least two terminal assembly;

[0007] The housing has a receiving cavity, and the heating band is housed in the receiving cavity;

[0008] The heating strip includes one or more heating bars, which are bent and wound alternately left and right multiple times to form the heating strip. The contact parts of the same heating bar or two adjacent heating bars are fixedly connected.

[0009] The terminal assembly is mounted on the housing and is electrically connected to the heating element inside the housing.

[0010] As a preferred embodiment of the uniform heating electric heater described in this utility model, the shell is a cylindrical shell, the heating belt is a disc-shaped heating belt, the diameter of the heating belt is <150mm, and / or the diameter of the heating belt is ≥60mm.

[0011] As a preferred embodiment of the uniform heating electric heater described in this utility model, one or more heating bars alternately bend in a Z-shape or at right angles, and the Z-shape bends and radially adjacent Z-shape bends form a rectangular structure.

[0012] As a preferred embodiment of the uniform heating electric heater described in this utility model, when there are multiple heating bars, the multiple heating bars are arranged side by side and fixedly connected to each other to form a heating belt.

[0013] As a preferred embodiment of the uniform heating electric heater described in this utility model, the contact portions of the same heating strip or two adjacent heating strips are fixedly connected by laser welding and brazing.

[0014] As a preferred embodiment of the uniform heating electric heater described in this utility model, the heating strip includes a first heating strip and a second heating strip. The first heating strip and the second heating strip are paired together, and two adjacent Z-shaped bends form a rectangular structure. The contact parts of the first heating strip and the second heating strip are fixedly connected.

[0015] As a preferred embodiment of the uniform heating electric heater described in this utility model, the first heating strip and the second heating strip constitute a heating strip group, and the contact portions of two adjacent heating strip groups are fixedly connected.

[0016] As a preferred embodiment of the uniform heating electric heater described in this utility model, the parts of the first heating strip and the second heating strip that are in contact are fixedly connected by laser welding and brazing.

[0017] As a preferred embodiment of the uniform heating electric heater described in this utility model, the parts of two adjacent heating strip groups that are in contact are fixedly connected by laser welding and brazing.

[0018] As a preferred embodiment of the uniform heating electric heater described in this utility model, the heating strip and the terminal assembly are fixedly connected by laser welding and brazing.

[0019] As a preferred embodiment of the uniform heating electric heater described in this utility model, the heating strip and the terminal assembly are fixedly electrically connected by a conductive structure.

[0020] As a preferred embodiment of the uniform heating electric heater described in this utility model, the heating strip is a stamped heating strip.

[0021] As a preferred embodiment of the uniform heating electric heater described in this utility model, the shell is a cylindrical structure with openings at both ends, and the heating belt is a circular heating belt.

[0022] As a preferred embodiment of the uniform heating electric heater described in this utility model, the axis of the shell is not parallel to the plane formed by the heating belt.

[0023] As a preferred embodiment of the uniform heating electric heater described in this utility model, the terminal assembly includes a ceramic insulating tube, a T-shaped sleeve, and a mounting post; the ceramic insulating tube is sleeved on the mounting hole, the heating band is fixedly connected to the T-shaped sleeve, neither the heating band nor the T-shaped sleeve is in contact with the housing, and the T-shaped sleeve and the mounting post are fixedly connected through the ceramic insulating tube.

[0024] As a preferred embodiment of the electric heater for uniform heating described in this utility model, the heating element has one or more heating elements;

[0025] When there are multiple heating belts, the multiple heating belts are arranged at intervals in the housing along the airflow direction, and the adjacent heating belts are electrically connected through connecting components and conductive sheets.

[0026] As a preferred embodiment of the uniform heating electric heater described in this utility model, the connecting assembly includes a bolt, an insulating component, and a nut; a connecting hole is provided on the housing, the insulating component is housed in the connecting hole, the insulating component has an insulating hole, the heating band and the conductive component are both sleeved on the bolt, the bolt is sleeved in the insulating hole, and the nut is fixedly screwed onto the bolt. The insulating component is configured such that the heating band, the conductive component, the bolt, and the nut are not electrically connected to the housing, and the heating band and the conductive component are electrically connected to the bolt.

[0027] As a preferred embodiment of the uniform heating electric heater described in this utility model, the connecting assembly further includes a nickel gasket, which is sleeved on the bolt and is in contact with the heating strip.

[0028] As a preferred embodiment of the uniform heating electric heater described in this utility model, a fixed bracket is also provided in the accommodating cavity, and the heating strip is fixedly connected to the fixed bracket through an insulating fastener;

[0029] The fastener includes a fixing rod and an insulating pad. The insulating pad is fitted onto the fixing rod and placed between the heating band and the fixing bracket and / or between two adjacent heating bands. The fixing rod passes through the heating band and is fixed to the fixing bracket.

[0030] As a preferred embodiment of the uniform heating electric heater described in this utility model, the insulating pad includes an insert portion and a spacer portion, wherein the insert portion extends into the space between the heating strips of the heating belt.

[0031] Compared with the prior art, the technical solution of this utility model has at least one or more of the following beneficial effects:

[0032] This patented heating strip eliminates the spiral design that hinders miniaturization. The heating strips feature alternating left and right bends in a V-shape, with two V-shaped bends forming a rectangular structure. Right-angle bends at the ends of the heating strips connect to the connecting posts. The bent heating strips are elongated, and multiple parallel heating strips form a circular heating strip. The two heating strip groups are symmetrically arranged, eliminating the internal wave structure and further reducing the size of the structure, making it suitable for use in small-space pipes (diameter < 150mm) and easy to install. This patented heater can be as small as φ60mm. During uniform heating tests, the research team found that the heating strip structure of this patent has better uniformity than traditional electric heating strips with internal wave structures. The maximum surface temperature deviation ΔTmax of traditional electric heating strips is 20℃, while the maximum surface temperature deviation ΔTmax of this patented electric heater is within 10℃. The research team speculates that this is due to the higher uniformity of the heating strip structure layout and a more rational heat dissipation / transfer path. Although the heat dissipation fins are eliminated, more uniform heating can be achieved.

[0033] The heating strip is formed by stamping, and the surface of the heating band is free from scratches and deformation, which shortens the processing time. There is no tension inside the heating band, and the heating band is flat in all places with complete adhesion between each layer of heating band.

[0034] The heating band of this patent is composed of two or more symmetrically combined heating strips, or even one, two, or more heating bands, the length of which determines the length acting on the current path. To obtain heating effects with different power, the resistance or structure of the heating band is changed to adapt to different power requirements. Methods for changing the resistance include altering the width or length of the heating band; then the heating resistance is set within the desired range, for example, 150mΩ to 750mΩ. Heat resistance is determined by the cross-sectional area and length, and materials with constant resistance are particularly preferred. Therefore, the length of the heating conductor and the resulting heating resistance can be adjusted by the width or length of the heating band.

[0035] The heating strips are fixed to the terminals and to each other using welding, employing both laser welding and brazing. Laser welding is used for initial fixing, followed by brazing to ensure sufficient contact between each heating strip or the terminal, preventing excessive contact resistance and further improving fixing strength and conductivity. In contrast, traditional resistance welding results in contact resistance, affecting conductivity, and also provides insufficient fixing strength.

[0036] The insulating pad has an indentation part and a separation part, which can stably support the heating belt, prevent the heating belt from shaking and deforming, and also avoid leakage.

[0037] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0038] To more clearly illustrate the technical solution of this utility model, 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 these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the structure of an existing electric heater;

[0040] Figure 2 This is a three-dimensional structural diagram of the heater for uniform heating described in this utility model;

[0041] Figure 3 This is a schematic diagram of the main structure of the heater for uniform heating described in this utility model;

[0042] Figure 4 This is a cross-sectional structural schematic diagram of the heater for uniform heating described in this utility model;

[0043] Figure 5 yes Figure 4 A cross-sectional perspective view of the heater used for uniform heating;

[0044] Figure 6 yes Figure 5 A magnified view of the middle R section.

[0045] Among them, 1-shell, 2-heating belt, 3-terminal assembly, 4-connection assembly, 11-accommodating cavity, 13-fixed bracket, 14-fixed rod, 15-insulating pad, 21-heating strip, 211-first heating strip, 212-second heating strip, 31-ceramic insulating tube, 32-T-shaped sleeve, 321-limiting part, 322-main body, 33-mounting post, 41-bolt, 42-nut, 43-nickel washer, 441-insulating sleeve, 442-first insulating sheet, 443-second insulating sheet, 91-conventional electric heating belt. Detailed Implementation

[0046] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0047] In the description of this utility model, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this utility model. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0048] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "provided with," "equipped with," "connected," "installed," "sleeved," "opened," and "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0049] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

[0050] Please refer to Figure 2-6 ,like Figure 2-6 As shown, this utility model provides an electric heater for uniform heating, which includes a housing 1, a heating band 2 and at least two terminal block assemblies 3;

[0051] The housing 1 has a receiving cavity 11, and the heating band 2 is housed in the receiving cavity 11;

[0052] The heating band 2 includes one or more heating strips 21, which are bent in a zigzag or right-angle manner multiple times, and the contact parts of the same heating strip 21 or two adjacent heating strips 21 are fixedly connected.

[0053] The terminal assembly 3 is mounted on the housing 1 and is electrically connected to the heating band 2 inside the housing 1.

[0054] In the example, a through mounting hole is provided on the housing 1, which is connected to the accommodating cavity 11. One end of the terminal assembly 3 is electrically connected to the heating band 2 inside the housing 1, and the other end of the terminal assembly 3 extends out of the housing 1.

[0055] Preferably, the shape of the heating band 2 conforms to the cross-sectional shape of the shell, where the cross-section is the plane containing the heating band 2. In the example, the shell 1 has a cylindrical cross-section, and the heating band 2 is a disc-shaped heating band with a diameter <150mm and / or a diameter ≥60mm. It should be noted that conformity here does not mean that the shape of the heating band 2 is strictly identical to the radial shape of the shell (i.e., completely the same). The disc shape here does not mean that the heating band is strictly disc-shaped, but rather that the shape of the heating band 2 is substantially close to the cross-sectional shape of the shell, and the outer contour of the heating band can be approximated as a disc shape (e.g., in this application). Figure 3 (As shown).

[0056] Preferably, when there are multiple heating bars 21, the multiple heating bars are arranged side by side and fixedly connected to each other to form a heating belt.

[0057] The electric heater of this patent is used in the exhaust system to rapidly heat the aftertreatment components of the exhaust gas; it is also used in SCR technology for exhaust gas recirculation; the exhaust gas flows through the heating belt and is heated by convection, and the heated exhaust gas transfers its heat to the catalyst along the flow direction.

[0058] This patented heating strip eliminates the spiral design that hinders miniaturization. The heating strips feature alternating left and right bends in a V-shape, with two V-shaped bends forming a rectangular structure. The right-angle bends at the ends of the heating strips connect to the connecting posts. The bent heating strips are elongated, and multiple parallel heating strips form a circular heating strip. The two heating strip groups are symmetrically arranged, eliminating the internal wave structure and further reducing the size of the structure, making it suitable for use in small-space conduits (diameter < 150mm) and easy to install. This patented heater can be as small as φ60mm. During uniform heating tests, the patent development team found that the heating strip structure of this patent is superior to internal wave structures (such as...). Figure 1 The uniformity shown is better. Figure 1 The maximum deviation of the surface temperature of the electric heater in the previous model is 20℃, while the maximum deviation of the surface temperature of the electric heater in this patent is within 10℃. The research and development team speculates that this is because the heating belt structure layout of this patent has higher uniformity and a more reasonable heat dissipation / heat transfer path. Although the heat dissipation fins have been eliminated, more uniform heating can be achieved.

[0059] Preferably, the shell 1 is a cylindrical structure with openings at both ends.

[0060] Preferably, the axis of the housing 1 is not parallel to the plane formed by the heating band 2. More preferably, the axis of the housing 1 is perpendicular to the plane formed by the heating band 2.

[0061] In the example, such as Figure 2-3 and Figure 5As shown, one or more heating strips 21 are alternately bent in a V-shape or at right angles, with the V-shaped bends forming a rectangular structure with radially adjacent V-shaped bends. In this example, the right-angle bend at the end of the heating strip 21 is used to connect to the terminal block.

[0062] Preferably, the contact portions of two adjacent heating bars 21 are fixedly connected by laser welding and brazing.

[0063] Preferably, the heating strip 21 is fixedly connected to the terminal assembly 3 by laser welding and brazing.

[0064] Preferably, the heating band 2 and the terminal assembly 3 are fixedly electrically connected by a conductive structure.

[0065] In a preferred embodiment, such as Figure 2-3 As shown, the heating strip 21 includes a first heating strip 211 and a second heating strip 212. The first heating strip 211 and the second heating strip 212 are paired together, with adjacent pairs bent in a V-shape to form a rectangular structure. The contact portions of the first heating strip 211 and the second heating strip 212 are fixedly connected. In this example, the first heating strip 211 and the second heating strip 212 are bent in a V-shape multiple times to form multiple rectangular structures. The contact portions of the first heating strip 211 and the second heating strip 212 after bending are fixedly connected by laser welding and brazing. In this example, the axial direction of the rectangular structure is perpendicular to the length direction of the heating strip 21. In this example, the two ends of the heating strip 21 extend symmetrically to the vicinity of the inner walls on both sides of the housing 1. In this example, the heating strip 21 is a stamped heating strip. The stamping process results in a heating strip surface free of scratches and deformation, shortens processing time, eliminates tension within the heating strip, ensures flatness throughout the heating strip, and ensures complete adhesion between each layer of heating strip.

[0066] Preferably, the first heating strip 211 and the second heating strip 212 constitute a heating strip group, and the contact portions of adjacent heating strip groups are fixedly connected. More preferably, the heating band 2 includes two heating strip groups, which are symmetrically arranged, and the adjacent edges of adjacent heating strip groups are fixedly connected by laser welding and brazing. In the example, the two heating strip groups form a circular heating band 2, which is housed within a cylindrical shell 1. In the example, adjacent portions of adjacent heating strip groups can also form multiple rectangular or polygonal structures. In the example, the contact portions of adjacent heating strip groups are fixedly connected by laser welding and brazing.

[0067] The heating band of this patent is composed of two or more symmetrically combined heating strips, or even one, two, or more heating bands, the length of which determines the length acting on the current path. To obtain heating effects with different power, the resistance or structure of the heating band is changed to adapt to different power requirements. Methods for changing the resistance include altering the width or length of the heating band; then the heating resistance is set within the desired range, for example, 150mΩ to 750mΩ. Heat resistance is determined by the cross-sectional area and length, and materials with constant resistance are particularly preferred. Therefore, the length of the heating conductor and the resulting heating resistance can be adjusted by the width or length of the heating band.

[0068] The heating strips are fixed to the terminals and to each other using welding, employing both laser welding and brazing. Laser welding is used for initial fixing, followed by brazing to ensure sufficient contact between each heating strip or the terminal, preventing excessive contact resistance and further improving fixing strength and conductivity. In contrast, traditional resistance welding results in contact resistance, affecting conductivity, and also provides insufficient fixing strength.

[0069] In a preferred embodiment, such as Figure 4-5 As shown, the terminal assembly 3 includes a ceramic insulating tube 31, a T-shaped sleeve 32, and a mounting post 33; the ceramic insulating tube 31 is fitted onto the mounting hole, the heating band 2 is fixedly connected to the T-shaped sleeve 32, neither the heating band 2 nor the T-shaped sleeve 32 is in contact with the housing 1, and the T-shaped sleeve 32 and the mounting post 33 pass through the ceramic insulating tube 31 and are fixedly connected.

[0070] In the example, there are two terminal assembly 3, one is the positive terminal assembly 3 and the other is the negative terminal assembly 3.

[0071] In the example, ceramic insulating tube 31 is a ceramic insulating tube with an alumina content greater than 95%.

[0072] In the example, the mounting post is electrically connected to an external power source.

[0073] Preferably, the length of the ceramic insulating tube 31 is greater than the thickness of the shell, and both ends of the ceramic insulating tube 31 protrude outward from the inner and outer surfaces of the shell, so that the heating band 2, the T-shaped sleeve 32, and the mounting post 33 do not contact the shell 1. Preferably, one end of the ceramic insulating tube 31 is also provided with a raised edge structure, the outer diameter of which is larger than the inner diameter of the corresponding mounting hole on the shell 1. During installation, it is only necessary to make the raised edge of the ceramic insulating tube 31 abut against the shell 1 to ensure that the heating band 2, the T-shaped sleeve 32, and the mounting post 33 do not contact the shell 1. Of course, this patent is not limited to this, and insulating sheets can also be provided on both sides of the shell, provided that the heating band 2, the T-shaped sleeve 32, and the mounting post 33 are not electrically connected to the shell 1.

[0074] Preferably, the heating band 2 is sleeved on the terminal assembly 3, and / or the heating band 2 and the terminal assembly 3 are fixedly connected by laser welding and brazing. In the example, the heating band 2 is sleeved on the T-shaped sleeve 32, and the heating band 2 is laser welded and brazed onto the T-shaped sleeve 32.

[0075] In the example, the inner wall of the mounting hole is provided with an internal thread, and the surface of the ceramic insulating tube 31 is provided with an external thread that matches the internal thread of the inner wall of the mounting hole. The ceramic insulating tube 31 is screwed and fixed to the mounting hole of the housing 1. In the example, the length of the ceramic insulating tube 31 is greater than the thickness of the housing 1, and both ends of the ceramic insulating tube 31 protrude outward from the inner and outer surfaces of the housing.

[0076] Preferably, the heating band 2 is electrically connected to the T-shaped sleeve 32. In the example, the heating band 2 is threaded onto the T-shaped sleeve 32 and fixedly connected to the T-shaped sleeve 32 by laser welding and brazing.

[0077] Preferably, the T-shaped sleeve 32 extends into the ceramic insulating tube 31, the heating band 2 does not contact the housing 1, the inner wall of the T-shaped sleeve 32 is provided with internal threads, the surface of the mounting post 33 is provided with external threads that match the internal threads of the inner wall of the T-shaped sleeve 32, and the mounting post 33 extends from outside the housing and is fixedly screwed into the T-shaped sleeve 32.

[0078] In this example, the T-shaped sleeve 32 includes a limiting part 321 and a main body 322. A through hole is provided on the heating band for passing through the main body 322. The outer diameter of the limiting part 321 is larger than the outer diameter of the main body 322 and the inner diameter of the through hole. The heating band 2 is sleeved on the main body 322 and abuts against the ceramic insulating tube 31. The main body 322 of the T-shaped sleeve 32 extends into the ceramic insulating tube 31. The mounting post 33 is fixedly installed inside the main body 322. In this example, the outer diameter of the limiting part 321 is larger than the inner diameter of the ceramic insulating tube 31.

[0079] In a preferred embodiment, such as Figure 4-5 As shown, there are at least two heating bands 2, which are spaced apart within the housing 1 along the direction of airflow.

[0080] Preferably, two adjacent heating bands 2 are connected in series, and there are two terminal assembly 3s, with the outermost heating band 2 connected to the corresponding terminal assembly 3.

[0081] Preferably, adjacent heating bands 2 are electrically connected via connecting components 4. In this example, the heating bands 2 are connected to their respective connecting components 4, and adjacent connecting components 4 are electrically connected via conductive elements.

[0082] like Figure 2-6As shown, the connecting assembly 4 includes a bolt 41, an insulating component, and a nut 42; a connecting hole is provided on the housing, the insulating component is housed in the connecting hole, and an insulating hole is provided on the insulating component. The heating band 2 and the conductive component are both sleeved on the bolt 41, the bolt 41 is sleeved in the insulating hole, and the nut 42 is fixedly screwed onto the bolt 41. The insulating component is configured such that the heating band 2, the conductive component, the bolt 41, and the nut 42 are not electrically connected to the housing, while the heating band 2 and the conductive component are electrically connected to the bolt 41.

[0083] In the example, bolt 41 is a conductive bolt, and nut 42 is a conductive nut.

[0084] In the example, the conductive element is a conductive sheet 51, which is located on the outside of the housing 1.

[0085] Further preferred, such as Figure 6 As shown, the connecting assembly 4 also includes a nickel gasket 43, which is fitted onto the bolt 41 and is in contact with the heating strip 21. In this example, the nickel gasket 43 is located on the side of the heating strip 21 away from the insulator. In this example, the nickel gasket 43 is a pure nickel gasket. Traditional stainless steel or copper gaskets have low conductivity or temperature resistance; this patent uses a pure nickel gasket, which has good conductivity and high temperature resistance.

[0086] This patent uses conductive sheets, nickel pads, and T-shaped sleeves for further electrical connection. If the terminal and heating band are only connected by welding, it is easy to generate large contact resistance and severe local heating, which makes the heating band easy to burn out. This patent adds a fixed electrical connection of conductive sheets, nickel pads, and T-shaped sleeves to avoid the problem of local heating and ensure its reliability.

[0087] Preferred, such as Figure 4-6 As shown, the insulating component includes an insulating sleeve 441, a first insulating sheet 442, and a second insulating sheet 443. The insulating sleeve 441 is housed within a connecting hole in the housing, and the first insulating sheet 442 and the second insulating sheet 443 are respectively disposed on both sides of the housing 1. In this example, the insulating hole sequentially passes through the first insulating sheet 442, the insulating sleeve 441, and the second insulating sheet 443.

[0088] In the example, the nickel gasket 43, heating band 2, first insulating sheet 442, insulating sleeve 441, second insulating sheet 443, and conductive component are sequentially threaded onto bolt 41, and nut 42 is screwed onto bolt 41 for fixation. In the example, the nickel gasket 43, heating band 2, and first insulating sheet 442 are located inside the housing 1, while the second insulating sheet 443, conductive component, and nut 42 are located outside the housing 1. In the example, insulating sleeve 441 is made of ceramic material.

[0089] In the example, one end of the conductive element is threaded onto a bolt of a connecting component 4, and the other end of the conductive element is threaded onto a bolt of another connecting component 4. The two heating bands 2 are connected in series through the connecting component 4 and the conductive element.

[0090] In the example, the terminal block assembly 3 and the connection assembly 4 are symmetrically arranged on both sides of the housing.

[0091] Specifically, there are two heating bands 2, namely a first heating band and a second heating band. The terminal assembly 3 includes a first terminal assembly and a second terminal assembly. The connecting assembly includes a first connecting assembly and a second connecting assembly. One end of the first heating band is electrically fixedly connected to the first terminal assembly, and the other end of the first heating band is electrically fixedly connected to the first connecting assembly. The first connecting assembly and the second connecting assembly are electrically connected through a conductive sheet. One end of the second heating band is electrically fixedly connected to the second connecting assembly, and the other end of the second heating band is electrically fixedly connected to the second terminal assembly. In the example, the first terminal assembly and the first connecting assembly are symmetrically arranged at both ends of the first heating band, and the second terminal assembly and the second connecting assembly are symmetrically arranged at both ends of the second heating band.

[0092] In the example, the insulating sleeve is a ceramic insulating sleeve with an alumina content of more than 95%.

[0093] In a preferred embodiment, such as Figure 4-5 As shown, a fixed bracket 13 is also provided inside the accommodating cavity 11, and the heating strip 21 is fixedly connected to the fixed bracket 13 through an insulating fastener.

[0094] Preferably, the fixing element is a fixing rod 14, which passes through the rectangular or polygonal gap in the heating band 2 and is fixedly connected to the fixing bracket 13. Preferably, fixing brackets 13 are provided on both sides of the heating band 2, and after the fixing rod 14 passes through the rectangular or polygonal gap in the heating band 2, both ends of the fixing rod 14 are fixed to the corresponding fixing brackets 13. In the example, the fixing rod is a heat-resistant steel fixing rod.

[0095] Preferably, an insulating pad 15 is also provided on the fixing rod 14. The insulating pad 15 is fitted onto the fixing rod 14 and is placed between the heating belt 2 and the fixing bracket 13.

[0096] Preferably, if there are at least two heating bands 2, an insulating pad 15 is also provided between each pair of heating bands 2.

[0097] In the example, insulating pad 15 is a ceramic insulating pad with an alumina content greater than 95%.

[0098] Further preferably, the insulating pad 15 includes an insert portion and a spacer portion. The insert portion extends into the space between the heating strips of the heating band, and the spacer portion is configured to separate the heating band from the fixed bracket, or between the heating bands. In the example, the outer diameter of the insert portion is consistent with the width of the rectangle, and the insert portion extends into the rectangle of the heating band 2. The outer diameter of the spacer portion is larger than the rectangular width of the heating band 2, and the spacer portion is placed between the fixed bracket 13 and the heating band 2 and / or between two heating bands 2. The insulating pad, with its insert portion and spacer portion, can stably support the heating band, prevent the heating band from shaking and deforming, and also avoid leakage. In addition, the insulating pad also helps prevent the heating band from rotating during the assembly of the terminal assembly and the connecting assembly. Specifically, before the terminal assembly and the connecting assembly are fixedly assembled, the insert portion of the insulating pad is first inserted into the heating band 2, and then the mounting post is tightened into the T-sleeve, or the nut is fixedly screwed onto the bolt, to prevent the heating band from rotating and deforming during the tightening process.

[0099] In the example, the fastener is an insulating fixing pin.

[0100] The heating strip is fixed to the terminal block assembly and connecting assembly by welding. The insulating pad extends into the rectangular structure of the heating strip, and the end of the heating strip is fixed and tightened by nuts and mounting posts, which reduces the stress after assembly with the heating tape and improves the service life of the product.

[0101] The technical features of all components in the above-described specific embodiments can be freely combined without conflict.

[0102] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "yet another embodiment," "another embodiment," "other embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Furthermore, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0103] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications and variations to the above embodiments within the scope of the present invention.

Claims

1. An electric heater for uniform heating, characterized in that, It includes a housing (1), a heating band (2), and at least two terminal block assemblies (3); The housing (1) has a receiving cavity (11), and the heating belt (2) is housed in the receiving cavity (11); The heating strip (2) includes one or more heating bars (21), which are bent and wound alternately left and right multiple times to form a heating strip. The contact parts of the same heating bar (21) or two adjacent heating bars (21) are fixedly connected. The terminal assembly (3) is mounted on the housing (1) and is electrically connected to the heating band (2) inside the housing (1).

2. The electric heater according to claim 1, characterized in that, The shell (1) is a cylindrical shell, and the heating belt (2) is a disc-shaped heating belt with a diameter of <150mm and / or a diameter of ≥60mm.

3. The electric heater according to claim 1, characterized in that, One or more heating bars (21) alternately bend in a Z-shape or at right angles, with the Z-shape bends forming a rectangular structure with radially adjacent Z-shape bends; and / or The contact portions of the same heating strip (21) or two adjacent heating strips (21) bent together are fixedly connected by laser welding and brazing; and / or When there are multiple heating bars (21), the multiple heating bars are arranged side by side and fixedly connected to each other to form a heating belt.

4. The electric heater according to claim 1, characterized in that, The heating strip (21) includes a first heating strip (211) and a second heating strip (212). The first heating strip (211) and the second heating strip (212) are paired together, and two adjacent zigzag bends form a rectangular structure. The contact parts of the first heating strip (211) and the second heating strip (212) are fixedly connected.

5. The electric heater according to claim 4, characterized in that, The first heating bar (211) and the second heating bar (212) constitute a heating bar group, and the contact parts of two adjacent heating bar groups are fixedly connected.

6. The electric heater according to claim 5, characterized in that, The parts of the first heating strip (211) and the second heating strip (212) that come into contact are fixedly connected by laser welding and brazing; and / or The contact portions of two adjacent heating bar groups are fixedly connected by laser welding and brazing; and / or The heating strip (21) is fixedly connected to the terminal assembly (3) by laser welding and brazing; and / or The heating band (2) and the terminal assembly (3) are fixedly electrically connected by a conductive structure.

7. The electric heater according to claim 1, characterized in that, The heating strip (21) is a stamped heating strip; and / or The shell (1) is a cylindrical structure open at both ends, and the heating belt is a circular heating belt; and / or The axis of the shell (1) is not parallel to the plane formed by the heating belt (2).

8. The electric heater according to claim 1, characterized in that, There are one or more heating bands (2); When there are multiple heating bands (2), the multiple heating bands (2) are spaced apart in the housing (1) along the airflow direction, and the adjacent heating bands (2) are electrically connected through the connecting assembly (4) and the conductive sheet; The connecting component (4) includes a bolt (41), an insulating element, and a nut (42); the housing has a connecting hole, the insulating element is housed in the connecting hole, the insulating element has an insulating hole, the heating band (2) and the conductive element are both sleeved on the bolt (41), the bolt (41) is sleeved in the insulating hole, the nut (42) is fixedly screwed onto the bolt (41), the insulating element is configured such that the heating band (2), the conductive element, the bolt (41) and the nut (42) are not electrically connected to the housing, and the heating band (2) and the conductive element are electrically connected to the bolt (41).

9. The electric heater according to claim 8, characterized in that, The connecting assembly (4) also includes a nickel gasket (43), which is fitted onto the bolt (41) and is in contact with the heating strip (21).

10. The electric heater according to claim 1, characterized in that, A fixed bracket (13) is also provided inside the accommodating cavity (11), and the heating strip (21) is fixedly connected to the fixed bracket (13) through an insulating fastener; The fasteners include a fixing rod (14) and an insulating pad (15). The insulating pad (15) is fitted onto the fixing rod (14) and is positioned between the heating band (2) and the fixing bracket (13) and / or between two adjacent heating bands (2). The fixing rod (14) passes through the heating band and is fixed to the fixing bracket (13); and / or The insulating pad (15) includes an insert and a spacer, the insert extending between the heating strips of the heating band.

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