Shovel sheet type PTC (Positive Temperature Coefficient) heating block

Abstract

The utility model discloses a shovel sheet type PTC heating block which comprises a fin type aluminum pipe, the fin type aluminum pipe comprises an aluminum pipe with a cavity, a heating core is arranged in the cavity, radiating fins are arranged on the upper end face and / or the lower end face of the aluminum pipe, and the upper side and the lower side of the cavity are attached to the upper end face and the lower end face of the heating core to form an upper end face and lower end face radiating structure. The left and right sides of the cavity are pressed and molded laterally by a mold and then fit with the left and right end faces of the heating core to form a left and right end face heat dissipation structure; the radiator is characterized in that the radiating fins are obtained by shoveling the upper end face and / or the lower end face of the aluminum tube, the section of each radiating fin is wavy, and the radiating fins are obtained by shoveling the upper end face and / or the lower end face of the aluminum tube. The radiator with the integrated structure is higher in heat transfer efficiency, namely higher in radiating efficiency, so that the temperature difference on the surface of the heating sheet can be effectively increased, and the power attenuation is obviously slowed down.

Description

Technical Field

[0001] The utility model belongs to the technical field of PTC heaters, and particularly relates to a shovel-type PTC heating block. Background Art

[0002] At present, fin-type PTC electric heaters are becoming popular in the applications of air conditioners and other air heating equipment, especially widely used for heating in the indoor units of split wall-mounted or cabinet air conditioners. Due to the structural characteristics of the existing fin-type PTC electric heaters, the heat dissipation fins are often formed by pleating thin aluminum sheets to form heat dissipation fins, and the heat dissipation fins are fixed to an aluminum profile tube by using glue. After the ceramic heating element and the electrode sheet for conduction are wrapped by an insulating material and inserted into the holes of the aluminum profile tube, heat generation and heat dissipation are realized. For a PTC heating block, the greater the temperature difference on its surface, the higher the heating efficiency and power of the PTC heating block. Obviously, the connection between the heat dissipation fins and the aluminum profile tube by bonding will inevitably cause loss of heat transfer, and then inevitably accelerate the power attenuation of the product. Summary of the Invention

[0003] The purpose of the utility model is to provide a shovel-type PTC heating block, aiming to improve the heat dissipation efficiency to effectively control the power attenuation of the heating block.

[0004] To solve the above technical problems, the purpose of the utility model is realized as follows:

[0005] A shovel-type PTC heating block includes a finned aluminum tube. The finned aluminum tube includes an aluminum tube with a cavity. A heating core is arranged in the cavity. Heat dissipation fins are arranged on the upper end face and / or the lower end face of the aluminum tube. The upper and lower sides of the cavity are attached to the upper and lower end faces of the heating core to form an upper and lower end face heat dissipation structure. The left and right sides of the cavity are attached to the left and right end faces of the heating core after being laterally pressed and formed by a mold to form a left and right end face heat dissipation structure. It is characterized in that: the heat dissipation fins are obtained by shoveling the upper end face and / or the lower end face of the aluminum tube, and the cross section of the heat dissipation fins is wavy.

[0006] On the basis of the above solution and as a preferred solution of the above solution: the heating core includes a ceramic heating sheet and electrode sheets attached to the upper and lower surfaces of the ceramic heating sheet. An insulating layer is arranged between the heating core and the cavity. It also includes a power cord, and the power cord is welded to the electrode sheet.

[0007] On the basis of the above solution and as a preferred solution of the above solution: both ends of the cavity are blocked; only the power cord passes out from the end of the cavity.

[0008] Based on the above solution and as a preferred solution to the above solution: The length of the heating core is less than the length of the cavity, so that both ends of the heating core are shorter than the outer end surface of the cavity; High-temperature resistant insulating material is filled between both ends of the heating core and the end surface of the cavity.

[0009] Based on the above solution and as a preferred solution to the above solution: The upper end surface and / or the lower end surface of the aluminum tube are concave near both side edges.

[0010] Based on the above solution and as a preferred solution to the above solution: The surface of the finned aluminum tube has an oxide layer.

[0011] The prominent and beneficial technical effects of the present utility model compared with the prior art are as follows: By obtaining heat dissipation fins on the upper end surface and / or the lower end surface of the aluminum tube through the method of shoveling, compared with the traditional way of bonding heat dissipation fins and aluminum profile tubes, the heat transfer efficiency of the integrated structure radiator is higher, that is, the heat dissipation efficiency is higher. Then, the temperature difference on the surface of the heating sheet can be effectively increased, and the power attenuation is significantly slowed down; In addition, the cross-section of the heat dissipation fin is wavy. Compared with the straight finned heat dissipation fin, the heat dissipation area is increased, and the heat dissipation efficiency is also significantly improved, further slowing down the power attenuation of the heating sheet. By blocking the openings at both ends of the cavity, the overall insulation and safety of the heating block are improved. Description of the Drawings

[0012] Figure 1 is a three-dimensional schematic diagram of the overall structure of the present utility model;

[0013] Figure 2 is a cross-sectional view of the present utility model;

[0014] Figure 3 is a top view of the overall structure of the present utility model;

[0015] Figure 4 is a general cut view of the present utility model;

[0016] Figure 5 is a three-dimensional diagram of the overall structure of Embodiment 2;

[0017] Figure 6 is a front view of the overall structure of Embodiment 2. Detailed Embodiments

[0018] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all the embodiments. Based on the given embodiments, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application.

[0019] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present 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 should not be construed as a limitation to the present application.

[0020] In the description of the present application, terms such as "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features.

[0021] Embodiment 1

[0022] See in detail Figures 1-4 As shown, the present application discloses a shovel-type PTC heating block, including a finned aluminum tube 10. The finned aluminum tube 10 includes an aluminum tube 11 having a cavity 11a. A heating core 20 is arranged in the cavity 11a. A heat dissipation fin 12 is arranged on the upper end face of the aluminum tube 11. The upper and lower sides of the cavity 11a are attached to the upper and lower end faces of the heating core 20 to form an upper and lower end face heat dissipation structure. The left and right sides of the cavity 11a are attached to the left and right end faces of the heating core 20 after being laterally pressed and formed by a mold to form a left and right end face heat dissipation structure; the heat dissipation fin 12 is obtained from the upper end face of the aluminum tube 11 through a shovel process (the shovel process is a prior art and will not be elaborated here). Thus, a finned aluminum tube 10 with an integral structure of the heat dissipation fin 12 and the aluminum tube 11 is formed. By obtaining the heat dissipation fin by shoveling on the upper end face and / or the lower end face of the aluminum tube, compared with the traditional way of bonding the heat dissipation fin and the aluminum profile tube, the heat transfer efficiency of the radiator with an integral structure is higher, that is, the heat dissipation efficiency is higher. Then, the temperature difference on the surface of the heating sheet can be effectively increased, and the power attenuation is significantly slowed down. In addition, it is further preferably that the cross section of the heat dissipation fin 12 is wavy. Compared with the straight finned heat dissipation fin, the heat dissipation area is increased, so the heat dissipation efficiency is also significantly improved, and the power attenuation of the heating sheet is further slowed down.

[0023] The heating core 20 includes a ceramic heating sheet 21 and electrode sheets 22 attached to the upper and lower surfaces of the ceramic heating sheet 21. An insulating layer 23 is provided between the heating core 20 and the cavity 11a. It also includes a power cord 24, and the power cord 24 is welded to the electrode sheet 22. It should be noted that the traditional connection method of the heating sheet is plug-in connection, that is, the end of the electrode sheet 22 is fixedly connected to the plug piece, and a plug is installed on the power cord 24, and the plug is inserted into the plug piece to achieve connection and conduction. On the one hand, the position of the plug-in connection is close to the heating part, and it is easy to deform after heating, resulting in loosening of the connection. On the other hand, the contact area of the plug-in connection method is small, that is, the resistance here is large. For the large temperature difference at the initial stage of heating, the power and current of the heating core 20 are bound to be large, then it is bound to cause large heat generation at the position of the plug-in connection, resulting in further oxidation and deformation of the local area, and the power-on performance is further deteriorated, and there is a high possibility of burning and damage. In this embodiment, by directly welding the power cord 24 to the electrode sheet 22, this problem can be greatly overcome; the power cord 24 used is insulated with high-temperature resistant materials, such as a glass fiber sleeve power cord, which greatly extends the service life of the heating block.

[0024] Both ends of the cavity 11a are blocked; only the power cord 24 passes out from the end of the cavity 11a. Specifically, in this embodiment, it is preferred that the length of the heating core 20 is less than the length of the cavity 11a, so that both ends of the heating core 20 are shorter than the outer end surface of the cavity 11a; a high-temperature resistant insulating material, such as high-temperature resistant silica gel, is filled between both ends of the heating core 20 and the end surface of the cavity 11a. With the certain fluidity of the high-temperature silica gel, the gap between the power cord 24 and the cavity end is filled. By blocking the openings at both ends of the cavity, the overall insulation and safety of the heating block are improved; of course, the electrical waterproofness can also be improved to a certain extent.

[0025] In addition, for details, see Figure 4As shown, in order to facilitate the insertion of the heating core 20 into the cavity 11a, the inner contour of the cavity 11a is preferably slightly larger than the size of the heating core 20. However, in order to improve the thermal conductivity of the heating core 20 and the finned aluminum tube, it is necessary to ensure that the inner wall of the cavity 11a is as close to the heating core as possible. Therefore, after the heating core 20 is inserted into the cavity, the aluminum tube 11 is squeezed by a press to force the cavity to deform, thereby pressing the heating core 20 to fit tightly. However, the position where the press presses down cannot be on the heat dissipation fins, otherwise the structure of the heat dissipation fins is easily damaged. For this reason, the present embodiment preferably has a concave portion near the two side edges 112 on the upper end surface 111 of the aluminum tube 11, and by cooperating with the corresponding mold, the position where the force of the mold is applied is only on the side edge 112. Of course, by concave the side edge 112, the side edge 112 and the side wall 111a adjacent to the upper surface 111 can form a positioning edge, so as to realize the positioning of the finned aluminum tube and the mold and ensure the pressing effect. Of course, considering the consistency of deformation during the pressing process, in this embodiment, the middle part of the two side walls 13 of the aluminum tube 11 is preferably concave into the cavity to form a triangular convex ridge 14 in the cavity. Then, when the side edge 112 is squeezed, the side wall 13 at the concave part is deformed first, so that the upper and lower end faces of the aluminum tube are close to each other and in contact with the heating plate 20. In addition, the size of the convex ridge 14 is reasonably selected so that after being squeezed into place at the side edge 112, the inner end edge 14a of the convex ridge 14 is as close to or just in contact with the side of the heating plate 20 as possible, so as to avoid excessive squeezing of the heating block and damage to it.

[0026] It should be noted that due to the relatively active chemical properties of aluminum, the finned aluminum tube is very prone to local oxidation during long-term storage and later long-term use, but the oxidation is often uneven, which leads to oxidation discoloration marks on the surface of the finned aluminum tube and even in severe cases, the heat dissipation fins are oxidized and corroded and broken, which on the one hand has an adverse effect on the appearance quality of the finished shovel-type PTC heating block, and on the other hand is not conducive to the long-term stable use of the shovel-type PTC heating block. In this embodiment, it is further preferred that the surface of the finned aluminum tube 10 has an oxide layer. Specifically, the oxide layer is obtained by performing an oxidation treatment on the finned aluminum tube 10, such as an anodizing treatment, so as to form an oxide layer with uniform thickness and high color consistency on the surface of the finned aluminum tube 10. The dense oxide layer can protect the inner layer from or delay oxidation, thereby improving the quality of the product and significantly extending its service life.

[0027] Embodiment 2

[0028] See Figures 5-6 As shown, the difference between this embodiment and the first embodiment is that heat dissipation fins 12 are provided on the upper end surface and the lower end surface of the aluminum tube 11 to adapt to the use of higher power occasions and improve the heat dissipation efficiency of the product and the power of the heating block.

[0029] The above embodiments are only preferred embodiments of the present utility model, and do not limit the protection scope of the present utility model accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of the present utility model shall be covered within the protection scope of the present utility model.

Claims

1. A shovel-type PTC heating block, comprising a fin-type aluminum tube (10), the fin-type aluminum tube (10) comprising an aluminum tube (11) having a cavity (11a), a heating core (20) being arranged in the cavity (11a), a heat dissipation fin (12) being arranged on the upper end surface and / or the lower end surface of the aluminum tube (11), the upper and lower sides of the cavity (11a) being bonded to the upper and lower end surfaces of the heating core (20) to form an upper and lower end surface heat dissipation structure, and the left and right sides of the cavity (11a) being bonded to the left and right end surfaces of the heating core (20) to form a left and right end surface heat dissipation structure after being formed by side compression molding by a mold; characterized in that: The heat dissipation fins (12) are obtained by scraping the upper end surface and / or the lower end surface of the aluminum tube (11), and the cross section of the heat dissipation fins (12) is wavy.

2. The shovel-type PTC heating block according to claim 1 is characterized in that: The heating core (20) comprises a ceramic heating sheet (21) and electrode sheets (22) attached to the upper and lower surfaces of the ceramic heating sheet (21); an insulating layer (23) is provided between the heating core (20) and the cavity (11a); and a power line (24) is also included, wherein the power line (24) is welded to the electrode sheet (22).

3. The shovel-type PTC heating block according to claim 2 is characterized in that: Both ends of the cavity (11a) are blocked; the power line (24) is only passed through the end of the cavity (11a).

4. The shovel-type PTC heating block according to claim 1 is characterized in that: The length of the heating core (20) is smaller than the length of the cavity (11a), so that both ends of the heating core (20) are shorter than the outer end surface of the cavity (11a); and high-temperature resistant insulating material is filled between the two ends of the heating core (20) and the end surface of the cavity (11a).

5. The shovel-type PTC heating block according to claim 1, characterized in that: The upper end surface and / or the lower end surface of the aluminum tube (11) are concave near the two side edges.

6. The shovel-type PTC heating block according to claim 1, characterized in that: The surface of the finned aluminum tube (10) has an oxide layer.

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