A fluid heating device with improved structure

Abstract

The present invention relates to electric heating technology, and aims to provide a fluid heating device with an improved structure. The device includes an upper groove plate and a lower groove plate, each of which has a semicircular groove on its surface. When fitted together, they form a tubular space for accommodating an electric heating tube, and the heating part of the electric heating tube fits tightly against its inner wall. An upper flow channel plate is provided on the outer side of the upper groove plate, and a distance is maintained between the two to form an upper flow channel space. The inner surface of the upper flow channel plate has a corrugated convex structure or a lattice convex structure. The outer side of the lower groove plate has a similar structure. A water inlet and a water outlet are provided on the upper flow channel plate, and a through hole for connecting the upper flow channel space and the lower flow channel space is provided on the upper groove plate and the lower groove plate. The present invention adopts a thin plate and a convex structure design, which can reduce weight and increase the heat exchange area, and can also make the fluid have a disturbing effect to increase the heat dissipation speed. Due to its compact structure, small size, high heat transfer efficiency, simple manufacturing process, small size, high power and long life.

Description

Technical Field

[0001] The present invention relates to electric heating technology, in particular to a fluid heating device with an improved structure. Background Art

[0002] In certain specific applications (such as heating the air conditioner and batteries of pure electric vehicles), electric heaters must be compact, powerful, and long-lasting. The heating tubes must achieve high power density to meet these high-power requirements. The heat dissipation module must be tightly connected to the heating tubes to form a fluid channel to quickly remove heat from the tubes. If the fluid cannot remove the heat from the heating tubes in a timely manner, the heating tubes will overheat and fail.

[0003] Currently, cast aluminum heaters are widely used. Their heating core is an electric heating tube coiled into a cylindrical shape, which is then cast with fin-shaped aluminum. The working principle is that the heating tube is heated by electricity, transferring heat to the aluminum wrapped around the outside of the heating tube. The aluminum then transfers the heat to the coolant, which then transfers the heat to the air conditioning system and battery system. However, this heater structure has the following technical drawbacks: The coiled heating tube cannot be unfolded, resulting in high heat in the heating center; the low-pressure casting process and the minimum wall thickness of the heater make the heater heavy; the cast aluminum heater has a short flow path, which does not disturb the fluid; and the bonding rate between aluminum die-casting and stainless steel tubes after casting is only a maximum of 90%. Prolonged heating will cause the bonding rate to decrease, resulting in leakage, poor heat dissipation, and other problems that affect the product life. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to overcome the deficiencies in the prior art and provide a fluid heating device with an improved structure.

[0005] In order to solve the above technical problems, the solution adopted by the present invention is:

[0006] Provided is a fluid heating device with an improved structure, comprising an electric heating tube, and also comprising an upper groove plate and a lower groove plate with opposite surfaces in close contact, wherein the upper and lower groove plates are respectively provided with semicircular grooves on their surfaces and, when in contact, together form a tubular space for accommodating the electric heating tube; the heating section of the electric heating tube is bent in the same horizontal direction to form a heating portion, which is clamped in the tubular space between the upper and lower groove plates and in close contact with the inner wall thereof;

[0007] An upper flow channel plate is provided on the outer side of the upper groove plate, and a distance is maintained between the two to form an upper flow channel space, and the inner surface of the upper flow channel plate has a corrugated convex structure or a lattice convex structure; a lower flow channel plate is provided on the outer side of the lower groove plate, and a distance is maintained between the two to form a lower flow channel space, and the inner surface of the lower flow channel plate has a corrugated convex structure or a lattice convex structure;

[0008] A water inlet and a water outlet are provided on the upper flow channel plate, and through holes for connecting the upper flow channel space and the lower flow channel space are provided on the upper groove plate and the lower groove plate.

[0009] As a preferred solution, the top surface of the corrugated protrusion structure of the upper flow channel plate is tightly fitted with the surface of the semicircular groove on the upper groove plate, or is fixedly connected by brazing; or,

[0010] A local corrugated convex structure is correspondingly provided on the outer surface of the upper groove plate except for the semicircular groove, and the top surfaces of the two parts of the corrugated convex structure are tightly fitted or fixedly connected by brazing;

[0011] The lower groove plate and the lower flow channel plate have the same structure and connection relationship as above.

[0012] As a preferred solution, the top surface of the lattice protrusion structure of the upper flow channel plate is directly and tightly fitted to the surface of the upper groove plate, or is fixedly connected by brazing; or,

[0013] A lattice convex structure is correspondingly provided on the outer surface of the upper groove plate except the semicircular groove, and the top surfaces of the two parts of the lattice convex structure are tightly fitted or fixedly connected by brazing.

[0014] The lower groove plate and the lower flow channel plate have the same structure and connection relationship as above.

[0015] As a preferred solution, the upper flow channel plate, upper groove plate, lower groove plate and lower flow channel plate respectively have extended edges, and are sealed by brazing or bite folding.

[0016] As a preferred solution, the heating portion of the electric heating tube is fixedly connected to the upper groove plate and the lower groove plate by brazing.

[0017] As a preferred solution, the lower flow plate has an upwardly extending side, so that the whole is in the shape of an open box; the lower groove plate, upper groove plate and upper flow plate are installed in the lower flow plate in sequence, with their respective edges or extended sides tightly fitting the inner wall of the side of the lower flow plate, and are fixedly connected by brazing.

[0018] As a preferred solution, the heating portion is formed by bending the heating section of the electric heating tube into an S-shape, an M-shape or a U-shape, or a combination structure of any two of these shapes, or a combination structure of three shapes.

[0019] As a preferred solution, a cover plate is further installed on the outer side of the upper flow channel plate; two water pipe joints are fixedly installed on the cover plate, and their installation positions correspond to the water inlet and the water outlet.

[0020] As a preferred solution, the corrugated protrusion structures of the upper flow channel plate and the lower flow channel plate are in the shape of several herringbone waves arranged in parallel, and an angle β is formed between the oblique lines of the herringbone waves and the median vertical line, and 15°≤β≤75°.

[0021] As a preferred solution, the lattice protrusion structure of the upper flow channel plate and the lower flow channel plate is composed of a number of protrusion structure monomers evenly arranged in a lattice shape. The protrusion structure monomer is in the shape of a cone, and an angle a is formed between its side surface and the top surface or bottom surface, and 60°≤a≤90°.

[0022] Compared with the prior art, the technical effects of the present invention are:

[0023] 1. Unlike the coiled cylindrical structure used in conventional electric heaters, this invention bends the heating section of the heating tube horizontally to form an S-, M-, or U-shaped heating area, which is then tightly bonded or brazed to a thin plate with a raised flow-disturbing structure. The thinness of the plate reduces overall weight while increasing heat dissipation. The corrugated or lattice-shaped raised structure increases the heat exchange area and creates a fluid-disturbing effect, increasing heat dissipation.

[0024] 2. The heater of the present invention can perfectly overcome the defects of the prior art and achieve the technical goals of small size, high power and long life due to its compact structure, small size, high heat transfer efficiency and simple manufacturing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is an exploded view of the structure of the electric heater in Example 1 of the present invention;

[0026] Figure 2 for Figure 1 Schematic diagram of the bottom side of the electric heater;

[0027] Figure 3 for Figure 1 Schematic diagram of the top side of the medium electric heater;

[0028] Figure 4 An electric heating tube bent into an M shape;

[0029] Figure 5 For water to flow Figure 1 Schematic diagram of flow direction in the flow channel space of the electric heater;

[0030] Figure 6 for Figure 1 Schematic diagram of the cross section of the electric heater in the AA and BB directions;

[0031] Figure 7 for Figure 1 Schematic diagram of the cross section of the electric heater in the CC and DD directions;

[0032] Figure 8 Schematic diagram of the angle β formed between the herringbone wave pattern and the median perpendicular line in Example 1;

[0033] Figure 9 This is an exploded view of the structure of the electric heater in Example 2 of the present invention;

[0034] Figure 10 for Figure 9 Schematic diagram of the bottom side of the electric heater;

[0035] Figure 11 for Figure 9 Schematic diagram of the top side of the medium electric heater;

[0036] Figure 12 The electric heating tube bent into an M shape in Example 2;

[0037] Figure 13 for Figure 9 Schematic diagram of the structure of the upper groove plate;

[0038] Figure 14 for Figure 9 Schematic diagram of the structure of the lower groove plate;

[0039] Figure 15 for Figure 9 Schematic diagram of the structure of the downflow plate;

[0040] Figure 16 for Figure 9 Schematic diagram of the structure of the upper flow channel plate;

[0041] Figure 17 for Figure 9 Schematic diagram of the cross section of the electric heater in the AA and BB directions;

[0042] Figure 18 for Figure 9 Schematic diagram of the cross section of the electric heater in the CC and DD directions;

[0043] Figure 19 Schematic diagram of the angle a between the side surface and the top surface or bottom surface of the protruding structure monomer in Example 2.

[0044] Figure 1 、 9 Reference numerals in the drawings: 1 water pipe joint, 2 cover plate, 3 upper flow channel plate, 4 upper groove plate, 5 electric heating tube, 6 lower groove plate, 7 lower flow channel plate. DETAILED DESCRIPTION

[0045] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0046] The serial numbers assigned to the components in this application, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of this application, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0047] In this application, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0048] Example 1

[0049] The fluid heating device with improved structure in this embodiment is as follows Figure 1-8 As shown, it includes, arranged from top to bottom, a cover plate 2, an upper flow channel plate 3, an upper groove plate 4, an electric heating tube 5, a lower groove plate 6, and a lower flow channel plate 7. The lower flow channel plate 7 has upwardly extending sides, giving it an open box shape as a whole; the lower groove plate 6, the upper groove plate 4, and the upper flow channel plate 3 are sequentially installed in the box-shaped space formed by the lower flow channel plate 7, with their respective edges or extended sides tightly attached to the inner wall of the side of the lower flow channel plate 7, and then fixedly connected by brazing.

[0050] The upper groove plate 4 and the lower groove plate 6 are tightly fitted with their opposing surfaces, each having a semicircular groove formed thereon. Together, they form a tubular space for accommodating the electric heating tube. The heating section of the electric heating tube 5 is bent in the same horizontal direction to form an M-shaped, W-shaped, or U-shaped heating portion, which is clamped in the tubular space between the upper groove plate 4 and the lower groove plate 6 and tightly fits the inner wall of the tubular space. An upper flow channel plate 3 is provided on the outer side of the upper groove plate 4, with a spacing between the two to form the upper flow channel space. The inner surface of the upper flow channel plate 3 has a corrugated convex structure. A lower flow channel plate 7 is provided on the outer side of the lower groove plate 6, with a spacing between the two to form the lower flow channel space. The inner surface of the lower flow channel plate 7 has a corrugated convex structure. The upper flow channel plate 3 is provided with a water inlet and outlet, and the upper and lower groove plates 4 and 6 are provided with through holes for connecting the upper and lower flow channel spaces. To extend the heat exchange flow path, increase heat exchange time, and improve heat exchange efficiency, the water inlet and outlet are located at opposite corners of the upper flow channel plate 3. Two water pipe connectors 1 are fixedly installed on the cover plate 2 at positions corresponding to the water inlet and outlet. For ease of installation and use, the two terminal ends of the electric heating tube 5 are located on the same side of the fluid heating device, which facilitates external wiring.

[0051] As a further preferred solution, the top surface of the corrugated protrusions on the upper flow channel plate 3 is tightly fitted to the surface of the semicircular grooves on the upper groove plate 4, or is securely connected by brazing. Alternatively, a corresponding localized corrugated protrusion is provided on the outer surface of the upper groove plate 4, excluding the semicircular grooves, with the top surfaces of the two corrugated protrusions tightly fitted to each other, or securely connected by brazing. The lower groove plate 6 and the lower flow channel plate 7 have the same structure and connection relationship as described above. This preferred design further enhances the internal connection strength of the product, while also increasing turbulence and enhancing heat exchange.

[0052] In this example, the sides of the upper flow plate 3, upper groove plate 4, lower groove plate 6, and lower flow plate 7 are stacked together in a flanging fashion to form a certain obtuse angle. This transforms the traditional linear connection between the thin plates into an improved surface connection, thereby increasing the weld area and enhancing the weld strength between the thin plates. Furthermore, the electric heating tube 5 is also brazed to the inner wall of the circular tubular space. Compared to the integral casting connection commonly used in the prior art, this connection offers advantages such as reduced leakage, improved heat exchange, and a longer service life.

[0053] Compared with the winding three-dimensional structure heating tube in the prior art, the electric heating tube 5 in this example is bent into an S shape, an M shape or a U shape on the same plane, or a combination structure of any two of these shapes, or a combination structure of three shapes. The heating volume can be expanded by bending, thereby increasing the power density of the electric heating tube 5. The electric heating tube 5 fits tightly with the thin-walled upper groove plate 4 and the lower groove plate 6, which increases the heat dissipation area of the electric heating tube 5 and can greatly improve its heat dissipation speed. Designing a corrugated convex structure on the inner side of the upper groove plate 4 and the lower groove plate 6 can increase the heat exchange area in the flow channel space, while increasing the disturbance effect to accelerate the heat exchange of the fluid. As a specific design example, the corrugated convex structure can select a whole row of herringbone wave shapes, and the angle range of the straight lines in the herringbone structure is between 0-180 degrees. The optimal disturbance angle can be calculated through simulation to accelerate the liquid flow rate and achieve the best heat dissipation effect.

[0054] As an alternative, the lower runner plate, lower groove plate 6, upper groove plate 4, and upper runner plate 3 may also be sealed by extending the edges, snapping, and folding. The fluid heating device may also omit the cover plate 2, with the two water pipe connectors 1 directly fixed to the water inlet and outlet of the upper runner plate 3.

[0055] In this example, the corrugated protrusions of the upper and lower flow plates are arranged in parallel, forming a herringbone wave pattern. The angle β formed between the diagonal lines of the herringbone wave pattern and the median vertical line is 15°≤β≤75°. The preferred angles β are 45° and 60°. Increasing β enhances heat transfer, but also increases flow resistance. Therefore, a β of 45° provides the highest overall energy efficiency factor.

[0056] Example 2

[0057] Compared to Example 1, this example replaces the corrugated raised structure on the inner surfaces of the upper and lower flow channel plates with a lattice-shaped raised structure. This structure consists of several raised structure units evenly arranged in a lattice pattern. Each raised structure unit is truncated cone-shaped, with an angle a formed between its side surface and the top or bottom surface, with a range of 60°≤a≤90°. While increasing the angle a too much will enhance heat transfer, it will also increase resistance and reduce overall performance.

[0058] exist Figure 19 Wherein, λ is the distance between the top centers of adjacent protruding structure monomers, M is the distance between the bottom side edges of adjacent protruding structure monomers, and d is the height of the truncated cone of the protruding structure monomer.

[0059] As a further preferred solution, the top surface of the lattice convex structure of the upper flow channel plate is directly in close contact with the surface of the upper groove plate, or is fixedly connected by brazing. Furthermore, a plurality of convex structure units can be added to the non-semicircular groove positions of the upper groove plate and the lower groove plate to increase turbulence and enhance heat exchange effect, as shown in the following example. Figure 13 、 14 As shown. Specifically, a lattice protrusion structure is provided on the outer surface of the upper groove plate, excluding the semicircular groove. The top surfaces of the two lattice protrusion structures are tightly fitted together or fixedly connected by brazing. The lower groove plate and the lower flow channel plate have the same structure and connection relationship as described above.

[0060] Examples of processing methods:

[0061] First, bend the electric heating tube 5 according to the design, forming an S-, M-, or U-shape (or a combination of multiple shapes) at the same level. Then, install the electric heating tube 5 in the circular tubular space between the upper and lower groove plates 4, 6. The upper and lower flow plates 3 and 7 are then assembled on either side of the upper and lower groove plates 4, 6, respectively. Finally, install the cover plate 2, and connect the two water pipe connectors 1 to the flanged holes on the cover plate 2. Once all parts are assembled, they are brazed in a furnace.

[0062] Usage examples:

[0063] First, connect the external water pipes to the two water pipe connectors 1. Let cold water flow in through the water inlet, filling the upper and lower flow channels before flowing out of the water outlet. Then, connect the electric heating tubes 5 to heat the water. The corrugated ridges in the upper and lower flow channels create turbulent water flow, enhancing heat exchange and achieving rapid heat exchange.

[0064] The fluid heating device of the present invention achieves extremely fast heat transfer (dissipation) speeds, and its compact, thin-walled heat exchange design enables the heater to achieve high power and long life in a small size. Therefore, the device can also be used in other fluid heating and steam heating equipment or products in other application environments.

Claims

1. A fluid heating device with an improved structure, comprising an electric heating tube, characterized in that: It also includes an upper groove plate and a lower groove plate with opposite surfaces tightly fitted together, each having a semicircular groove on its surface and forming a circular tubular space for accommodating the electric heating tube after being fitted together; the heating section of the electric heating tube is bent in the same horizontal direction to form a heating portion, and the heating portion is clamped in the circular tubular space between the upper groove plate and the lower groove plate and tightly fitted with the inner wall thereof; An upper flow channel plate is provided on the outer side of the upper groove plate, and a distance is maintained between the two to form an upper flow channel space, and the inner surface of the upper flow channel plate has a corrugated convex structure or a lattice convex structure; a lower flow channel plate is provided on the outer side of the lower groove plate, and a distance is maintained between the two to form a lower flow channel space, and the inner surface of the lower flow channel plate has a corrugated convex structure or a lattice convex structure; A water inlet and a water outlet are provided on the upper flow channel plate, and a through hole for connecting the upper flow channel space and the lower flow channel space is provided on the upper groove plate and the lower groove plate; The lower runner plate has an upwardly extending side, making it an open box-shaped as a whole; the lower groove plate, upper groove plate and upper runner plate are installed in the lower runner plate in sequence, with their respective edges or extended sides tightly fitting the inner wall of the side of the lower runner plate, and are fixedly connected by brazing.

2. The fluid heating device according to claim 1, characterized in that The top surface of the corrugated convex structure of the upper flow channel plate is closely fitted with the surface of the semicircular groove on the upper groove plate, or fixedly connected by brazing; or A local corrugated convex structure is correspondingly provided on the outer surface of the upper groove plate except for the semicircular groove, and the top surfaces of the two parts of the corrugated convex structure are tightly fitted or fixedly connected by brazing; The lower groove plate and the lower flow channel plate have the same structure and connection relationship as above.

3. The fluid heating device according to claim 1, characterized in that The top surface of the lattice protrusion structure of the upper flow channel plate is directly and tightly fitted to the surface of the upper groove plate, or fixedly connected by brazing; or, A lattice convex structure is correspondingly provided on the outer surface of the upper groove plate except for the semicircular groove, and the top surfaces of the two parts of the lattice convex structure are tightly fitted or fixedly connected by brazing; The lower groove plate and the lower flow channel plate have the same structure and connection relationship as above.

4. The fluid heating device according to claim 1, characterized in that The heating portion of the electric heating tube is fixedly connected to the upper groove plate and the lower groove plate by brazing.

5. The fluid heating device according to claim 1, characterized in that The heating portion is formed by bending the heating section of the electric heating tube into an S-shape, an M-shape or a U-shape, or a combination structure of any two of these shapes, or a combination structure of three shapes.

6. The fluid heating device according to claim 1, characterized in that A cover plate is also installed on the outer side of the upper flow channel plate; two water pipe joints are fixedly installed on the cover plate, and the installation positions thereof correspond to the water inlet and the water outlet.

7. The fluid heating device according to claim 1, characterized in that The corrugated protrusion structures of the upper flow channel plate and the lower flow channel plate are in the shape of a plurality of herringbone waves arranged in parallel, and an angle β is formed between the oblique lines of the herringbone waves and the median vertical line, and 15°≤β≤75°.

8. The fluid heating device according to claim 1, characterized in that The lattice protrusion structure of the upper flow channel plate and the lower flow channel plate is composed of a number of protrusion structure monomers evenly arranged in a lattice shape. The protrusion structure monomer is in a frustum shape, and an angle a is formed between its side surface and the top surface or bottom surface, and 60°≤a≤90°.

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