Electric heater with temperature measuring tube anti-impact protection structure

Abstract

The utility model relates to an electric heating technology, and aims to provide an electric heater with a temperature measuring tube anti-impact protection structure. The electric heater comprises a junction box, a connecting flange and a plurality of electric heating pipes, a temperature measuring tube is coaxially arranged between the electric heating tubes, an anti-impact protection tube is coaxially sleeved on the outer side of the temperature measuring tube, a distance is kept between the anti-impact protection tube and the temperature measuring tube, two ends of the anti-impact protection tube are opened, and a plurality of through holes are uniformly formed in a tube body; and one end of the anti-impact protection tube is fixedly arranged on the connecting flange, and the other end of the anti-impact protection tube is connected to each electric heating tube through a porous bracket with a flanging structure. The product can prevent flowing liquid from directly impacting the temperature measuring tube, and the hole can also enable the temperature measuring tube to be in contact with the flowing liquid, so that accurate induction of temperature change is ensured. One end of the anti-impact protection tube is fixed on the connecting flange, and the other end of the anti-impact protection tube is connected to each electric heating tube through a porous bracket with a flanging structure, thereby forming a reinforced supporting structure, effectively avoiding vibration and prolonging the service life of the product.

Description

Technical Field

[0001] The utility model relates to electric heating technology, in particular to an electric heater with a temperature measuring tube anti-impact protection structure. Background Art

[0002] Electric heaters using electric heating tubes are widely used in a wide variety of industrial production equipment. For example, in many liquid heating scenarios, a common electric heater structure consists of a terminal box, a connecting flange, and multiple or multiple groups of electric heating tubes arranged in sequence along the axial direction. The liquid to be heated flows through the sleeve (or pipe fitting) where the electric heating tubes are located, and the turbulent flow causes heat exchange, raising its temperature.

[0003] To precisely control the heated liquid, a temperature probe is required in the electric heater. This probe is typically installed in a hollow, closed-end sleeve, forming a temperature measuring tube. The open end is inserted into the mounting hole of a connecting flange and secured by brazing. Unlike electric heating tubes, the lack of internal filler in temperature measuring tubes results in lower overall strength. The long, strip-shaped tube, subjected to prolonged impact from the turbulent liquid, is susceptible to stress at the welded joints at its base, which can easily loosen and break, leading to failure of the temperature measuring tube and, consequently, malfunction of the electric heating tube.

[0004] Current electric heaters also feature brackets or clamps installed at the closed end of the temperature measuring tube to secure the tube to the heater. However, these brackets or clamps can become loose or displaced over time, causing friction and vibration on the tube or heater. This not only creates noise during operation but can even cause wear on the tube wall, compromising the heater's smooth operation.

[0005] Therefore, it is necessary to make reasonable improvements to the product structure to solve the problem of anti-impact protection of the temperature measuring tube. Utility Model Content

[0006] The technical problem to be solved by the utility model is to overcome the deficiencies in the prior art and provide an electric heater with an anti-impact protection structure for a temperature measuring tube.

[0007] In order to solve the above technical problems, the solution adopted by the present invention is:

[0008] Provided is an electric heater with an anti-impact protection structure for temperature measuring tubes, comprising a junction box, a connecting flange and a plurality of electric heating tubes arranged in sequence along the axial direction; a coaxially arranged temperature measuring tube is provided between the electric heating tubes, the temperature measuring tube comprising a hollow sleeve with a closed outer end and a built-in temperature probe, the open end of the sleeve passes through a mounting hole on the connecting flange and is fixed, and a wire connected to the temperature probe is led into the junction box through the open end of the sleeve; an anti-impact protection tube is coaxially sleeved on the outside of the temperature measuring tube and kept at a distance from the temperature measuring tube, the two ends of the anti-impact protection tube are open, and a plurality of through holes are evenly arranged on the tube body; one end of the anti-impact protection tube is fixedly mounted on the connecting flange, and the other end is connected to the electric heating tubes via a porous bracket with a flanging structure.

[0009] As an improved solution, the body of the porous bracket is an integrated sheet structure, and the edge of each opening thereof has a flange structure perpendicular to the bracket body; the flange structure is tightly embedded in the straight pipe section and the impact-proof protective tube of the electric heating tube by riveting, and its outer edge is fixedly connected to the outer surfaces of the two by brazing.

[0010] As an improved solution, the edge of the bracket opening on the other side opposite to the flange structure is also fixedly connected to the outer surface of the electric heating tube and the anti-impact protection tube by brazing.

[0011] As an improved solution, the porous bracket is arc-shaped, and the anti-impact protection tube and the straight pipe section of at least one electric heating tube are respectively fixed in each opening; or, the porous bracket is disc-shaped, and the anti-impact protection tube and the straight pipe sections of all electric heating tubes are respectively fixed in each opening.

[0012] As an improved solution, the flange structure of the porous stent is a complete annular protrusion, or a plurality of arc-shaped protrusions arranged at intervals in the annular direction.

[0013] As an improved solution, the porous bracket is an integrated structure made of metal sheets by stamping, and the flange structures of the openings on the same bracket are all located on the same side surface of the bracket.

[0014] As an improved solution, an annular groove or an annular sunken step is provided around the mounting hole of the temperature measuring tube on the connecting flange; the end of the anti-impact protective tube is embedded in the annular groove or the annular sunken step, and its outer edge is fixedly connected to the outer edge of the groove or step by brazing.

[0015] As an improved solution, the impact-proof protective tube is made of a mesh plate with a plurality of through holes arranged therein, which is formed by bending and welding, with non-perforated areas being retained at both ends.

[0016] As an improved solution, the through holes on the impact-proof protective tube are arranged in multiple rows along the axial direction, and the through holes in each row are parallel to each other or staggered.

[0017] As an improved solution, at least one group of U-shaped electric heating tubes is fixedly installed on the connecting flange, and the electric heating tubes in the same group have the same shape and size and are arranged parallel to each other; when there are multiple groups of electric heating tubes, based on the different lengths of the straight pipe sections and the span differences of the arcs of the non-connection ends, the electric heating tubes of different groups are installed in a nested manner; the connection ends of each electric heating tube pass through the connecting flange and extend into the inner cavity of the junction box, and are wired according to their groups; the temperature measuring tube and each group of electric heating tubes are respectively connected to an external controller through wires, and the controller adjusts the power of the electric heater by changing the number of connected groups of electric heating tubes based on the temperature measurement data obtained by the temperature measuring tube.

[0018] Compared with the prior art, the technical effects of the present invention are:

[0019] 1. In the utility model, the temperature measuring tube is protected by using an anti-impact protection tube fixed at both ends, so that the flowing liquid will not directly impact the temperature measuring tube. The dense holes on the anti-impact protection tube can also keep the temperature measuring tube in contact with the flowing liquid, ensuring that the temperature probe in the temperature measuring tube can accurately sense changes in the liquid temperature.

[0020] 2. In the product of the present invention, one end of the impact-proof protective tube is fixed to the connecting flange, and the other end is connected to each electric heating tube through a porous bracket with a flanging structure, thereby forming a reinforced support structure. Even under the impact of high-flow refrigerant medium, since each electric heating tube is fixedly connected by a flanging structure and brazing, each electric heating tube and the bracket will not be displaced relative to each other, which can effectively avoid the safety hazards caused by the crevice corrosion principle between the electric heating tube and the bracket, avoid external scratches caused by vibration, and extend the service life of the product. By adopting a dual fixing method of riveting and brazing, the relative movement of the bracket and the electric heating tube caused by water flow impact during use can be avoided, the oxide layer on the surface of the electric heating tube can be avoided from being scratched, and noise can be prevented.

[0021] 3. This new product utilizes different straight tube lengths and non-connection end arcs to allow for nested installation of different groups of heating tubes. This allows for the accommodation of more groups of heating tubes within a heating sleeve or container. By controlling the heating power by switching the power on and off between different groups, refrigerant temperature can be more precisely controlled, resulting in more stable operation and smoother regulation of the air conditioner.

[0022] 4. The impact-resistant protective tube in this utility model utilizes proven stamping, sheet rolling, and welding processes. The porous bracket requires only stamping, resulting in a simple and cost-effective manufacturing process. Installation also utilizes proven riveting and brazing techniques for secure connection, making it easy to operate. Consequently, the overall manufacturing and installation process does not significantly increase costs compared to traditional technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The utility model is an electric heater with a temperature measuring tube anti-impact protection structure.

[0024] Figure 2 for Figure 1 Partial cross-sectional view of the product.

[0025] Figure 3 Schematic diagram of the structure of the impact protection tube.

[0026] Figure 4 Schematic diagram of the structure of the disc-shaped porous scaffold.

[0027] Figure 5 Schematic diagram of the structure of the arc-shaped porous bracket.

[0028] The reference numerals are: porous bracket 1; anti-impact protection tube 2; electric heating tube 3; connecting flange 4; junction box 5; temperature measuring tube 6. DETAILED DESCRIPTION

[0029] The specific implementation of the present utility model is described in detail below with reference to the accompanying drawings.

[0030] like Figure 1 、 2 As shown, the electric heater with a temperature measuring tube impact protection structure in the present invention includes a junction box 5, a connecting flange 4, and multiple electric heating tubes 3 arranged in axial sequence. A coaxially arranged temperature measuring tube 6 is provided between each electric heating tube 3. The temperature measuring tube 6 consists of a hollow sleeve with a closed outer end and a built-in temperature probe. The open end of the sleeve passes through the mounting hole in the connecting flange 4 and is fixed thereto. The wire connecting the temperature probe is led from the open end of the sleeve to the junction box 5. The connection between the electric heating tube 3 or the temperature measuring tube 6 and the connecting flange 4 can be fixed and sealed using full-circle argon arc welding as per conventional practice.

[0031] To address the impact protection issue for the temperature measuring tube, this application innovatively proposes coaxially inserting a spaced-apart impact protection tube 2 around the outside of the temperature measuring tube 6. This impact protection tube 2 is made from a mesh plate with multiple through-holes, which is bent and welded, leaving non-perforated areas at both ends. After forming, it becomes a hollow structure with open ends, and multiple through-holes are evenly distributed throughout the tube. These through-holes are arranged in multiple rows along the axial direction, with each row of through-holes arranged parallel to or staggered.

[0032] In order to prevent the impact of flowing liquid from affecting the stability of the anti-impact protection tube 2, the present invention adopts a method of fixing both ends: one end is fixedly installed on the connecting flange 4, specifically, an annular groove or annular sunken step is provided around the mounting hole of the temperature measuring tube 6 on the connecting flange 4; the end of the anti-impact protection tube 2 is embedded and installed in the annular groove or annular sunken step, and its outer edge is fixedly connected to the outer edge of the groove or step by brazing. The other end is connected to each electric heating tube 3 through a porous bracket 1 with a flange structure. The main body of the porous bracket 1 is an integrated sheet structure, and the edge of each opening thereof has a flange structure perpendicular to the bracket body. The flange structure is tightly embedded in the straight pipe section of the electric heating tube 3 and the anti-impact protection tube 2 by riveting, and its outer edge is fixedly connected to the outer surface of both by brazing; the edge of the bracket opening on the other side opposite to the flange structure is also fixedly connected to the outer surface of the electric heating tube 3 and the anti-impact protection tube 2 by brazing.

[0033] The porous bracket 1 is an integrated structure made of metal sheets by stamping. The flange structures of each opening on the same bracket are located on the same side surface of the bracket. The shape of the porous bracket can be arc-shaped ( Figure 5 As shown), the anti-impact protection tube 2 and the straight tube section of at least one electric heating tube 3 are fixed in each opening. Alternatively, the porous support 1 is disc-shaped ( Figure 4 (As shown), the impact protection tube 2 and the straight sections of all electric heating tubes 3 are fixed in their respective openings. Obviously, the latter solution provides greater connection stability. The flange structure can be a complete annular protrusion or multiple circular arc-shaped protrusions arranged at intervals in the annular direction.

[0034] According to the actual application scenario requirements, the form and quantity of the electric heating tube 3 can be adaptively changed. For example, the electric heating tube 3 can be selected from various schemes such as multiple straight tubes, single U-shaped tubes, multiple single-group U-shaped tubes, and multiple multi-group U-shaped tubes. Taking multiple two-group U-shaped tubes as an example, two groups of U-shaped electric heating tubes are fixedly installed on the connecting flange 4. The electric heating tubes in the same group have the same shape and size and are arranged parallel to each other; based on the different lengths of the straight tube sections and the span differences of the non-connection end arcs, the two groups of electric heating tubes are installed in a nested manner; the connection ends of each electric heating tube extend into the inner cavity of the junction box after passing through the connecting flange, and are wired according to their groups; the temperature measuring tube and each group of electric heating tubes are respectively connected to an external controller through wires, and the controller adjusts the power of the electric heater by changing the number of groups of electric heating tubes connected according to the temperature measurement data obtained by the temperature measuring tube. For example, when two groups of electric heating tubes 3 are connected in a star-shaped manner, three adjustment options of 33% power, 67% power and full power can be achieved.

[0035] Based on the above description, although the present invention has been disclosed with preferred embodiments, those skilled in the art can utilize the above-disclosed structures and technical contents to create equivalent embodiments without departing from the scope of the present invention. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention shall fall within the scope of the present invention.

Claims

1. An electric heater with a temperature measuring tube impact protection structure, comprising a junction box, a connecting flange, and a plurality of electric heating tubes arranged in sequence along the axial direction; a coaxially arranged temperature measuring tube is provided between each electric heating tube, the temperature measuring tube comprising a hollow sleeve with a closed outer end and a built-in temperature probe, the open end of the sleeve passing through a mounting hole in the connecting flange and being fixed thereto, and a wire connected to the temperature probe is led from the open end of the sleeve to the junction box; characterized in that An anti-impact protective tube is coaxially sleeved on the outside of the temperature measuring tube and kept at a distance from it. Both ends of the anti-impact protective tube are open, and a number of through holes are evenly arranged on the tube body; one end of the anti-impact protective tube is fixedly installed on the connecting flange, and the other end is connected to each electric heating tube through a porous bracket with a flanging structure.

2. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: The main body of the porous bracket is an integrated sheet structure, and the edge of each opening thereof has a flange structure perpendicular to the bracket body; the flange structure is tightly embedded in the straight pipe section and the anti-impact protection pipe of the electric heating pipe by riveting, and its outer edge is fixedly connected to the outer surface of the two by brazing.

3. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 2, characterized in that: The edge of the opening of the bracket on the other side opposite to the flange structure is also fixedly connected to the outer surface of the electric heating tube and the anti-impact protection tube by brazing.

4. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: The porous bracket is arc-shaped, and the anti-impact protection tube and the straight tube section of at least one electric heating tube are respectively fixed in each opening; or, the porous bracket is disc-shaped, and the anti-impact protection tube and the straight tube sections of all electric heating tubes are respectively fixed in each opening.

5. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: The flange structure of the porous stent is a complete annular protrusion, or a plurality of arc-shaped protrusions arranged at intervals in the annular direction.

6. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: The porous bracket is an integrated structure made of metal sheets by stamping, and the flange structures of the openings on the same bracket are all located on the same side surface of the bracket.

7. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: An annular groove or an annular sunken step is provided around the mounting hole of the temperature measuring tube on the connecting flange; the end of the anti-impact protection tube is embedded in the annular groove or the annular sunken step, and its outer edge is fixedly connected to the outer edge of the groove or step by brazing.

8. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: The anti-impact protection tube is made of a mesh plate with a plurality of through holes arranged thereon through bending and welding, and non-perforated areas are reserved at both ends thereof.

9. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: The through holes on the impact-proof protective tube are arranged in a plurality of rows along the axial direction, and the through holes in each row are parallel to each other or arranged in a staggered manner.

10. The electric heater with a temperature measuring tube anti-impact protection structure according to claim 1, characterized in that: At least one group of U-shaped electric heating tubes is fixedly installed on the connecting flange. The electric heating tubes in the same group have the same shape and size and are arranged parallel to each other. When there are multiple groups of electric heating tubes, based on the different lengths of the straight tube sections and the span differences of the arcs of the non-connection terminals, the electric heating tubes of different groups are installed in a nested manner. The connection terminals of each electric heating tube pass through the connecting flange and extend into the inner cavity of the junction box, and are connected according to their groups. The temperature measuring tube and each group of electric heating tubes are respectively connected to an external controller through wires. The controller adjusts the power of the electric heater by changing the number of connected groups of electric heating tubes based on the temperature measurement data obtained by the temperature measuring tube.

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