An explosion-proof and flame-retardant liquid-cooled high-voltage automotive cable and its cable sheathing equipment.

Abstract

This utility model discloses an explosion-proof and flame-retardant liquid-cooled high-voltage automotive cable and its cable sheathing equipment. The cable includes a liquid-cooling pipe, a bare copper conductor, a wrapping layer, an explosion-proof tin-plated braided copper mesh, and a polyolefin insulation layer; the liquid-cooling pipe is located in the center of the cable. The cable sheathing equipment is a screw extruder, and the extrusion die is a double-layer die, including an inner die tube and an outer die tube. This utility model can effectively improve the cooling efficiency of the cable by setting up the liquid-cooling pipe, reducing the risk of fire caused by cable overload during the operation of electric vehicles, and improving the safety of electric vehicle operation. The cable sheathing equipment provided by this utility model, through the setting of the double-layer extrusion die, can effectively reduce the risk of compression deformation of the liquid-cooling pipe during the extrusion operation, ensuring the cooling efficiency of the cable.

Description

Technical Field

[0001] This utility model relates to the field of electric vehicle cable technology, and more specifically to an explosion-proof, flame-retardant, liquid-cooled high-voltage automotive cable and its cable sheathing equipment. Background Technology

[0002] The domestic electric vehicle industry is currently in a growth phase, and automakers are placing increasingly higher demands on electric vehicles' range, high-current charging, and explosion-proof safety. Meanwhile, the cable connections between battery packs in electric vehicles currently use multiple copper cable harnesses. These cables are numerous and heavy, and with the increasing discharge rate, the current they carry also increases. During operation, the rising internal temperature of the vehicle causes a decrease in current carrying capacity, resulting in significant heat generation and a high risk of combustion, seriously endangering the safe operation of electric vehicles and the personal safety of passengers. Summary of the Invention

[0003] The purpose of this invention is to provide an explosion-proof, flame-retardant, liquid-cooled high-voltage automotive cable and its cable sheathing equipment to solve the problems existing in the prior art.

[0004] To achieve the above objectives, the present invention provides an explosion-proof and flame-retardant liquid-cooled high-voltage automotive cable comprising a liquid-cooling pipe, a bare copper conductor, a wrapping layer, an explosion-proof tin-plated braided copper mesh, and a polyolefin insulation layer; wherein the liquid-cooling pipe is located in the center of the cable, the bare copper conductor consists of several bare copper wires evenly arranged around the liquid-cooling pipe; the wrapping layer overlaps and wraps around the bare copper conductor, an explosion-proof tin-plated braided copper mesh is provided outside the wrapping layer, and an irradiated cross-linked low-smoke halogen-free flame-retardant polyolefin insulation layer is provided outside the explosion-proof tin-plated braided copper mesh.

[0005] Furthermore, the polyolefin insulation layer includes an inner insulation layer and an outer insulation layer, wherein the thickness of the inner insulation layer is 1 / 5 to 1 / 3 of the thickness of the outer insulation layer.

[0006] This application also discloses a cable sheathing device for explosion-proof and flame-retardant liquid-cooled high-voltage automotive cables. The cable sheathing device is a screw extruder, and the extrusion die is a double-layer die, including an inner die tube and an outer die tube. The inner die tube is disposed inside the outer die tube, coaxial with the outer die tube, and fixed to the inner wall of the outer die tube by a connecting piece.

[0007] Furthermore, the inner mold tube and the outer mold tube are hollow tubular structures, and their inner diameter gradually decreases from the wire feed end to the wire discharge end.

[0008] Furthermore, the extrusion die includes a first outer die section, a second die section, a third outer die section, a fourth outer die section, a first inner die section, and a third inner die section; the first outer die section, the second die section, the third outer die section, and the fourth outer die section are connected by bolts; the second die section includes an outer die ring 1, an inner die ring, and several connecting plates, the inner die ring is disposed inside the outer die ring and is coaxial with the outer die ring, the outer side of the inner die ring is fixedly connected to the inner wall of the outer die ring f21 by connecting plates, and the first inner die section and the third inner die section are connected to both sides of the inner die ring by threaded structures.

[0009] Furthermore, the first outer mold section, the second mold section, and the third outer mold section are connected to the extrusion equipment by long bolts, and the fourth outer mold section is connected to the third outer mold section by short bolts.

[0010] Furthermore, the first outer mold section, the second mold section, the third outer mold section, and the fourth outer mold section are provided with through holes in the center, and their inner diameters are smoothly transitioned; the first inner mold section, the inner mold ring, and the third inner mold section are provided with through holes in the center, and their inner and outer diameters are smoothly transitioned.

[0011] Furthermore, the outer contour of the first inner mold section near the feed end is frustum-shaped, with a smaller outer diameter on the side near the feed end.

[0012] The cable provided by this utility model can effectively improve the current-carrying capacity of the cable. Through testing, the applicant has found that the current-carrying capacity of the technical solution presented in this application can be increased by 135% under the same cross-sectional area of ​​copper cable. The liquid cooling pipe effectively improves the cooling efficiency of the cable, reducing the risk of fires caused by cable overload during the operation of electric vehicles and improving the safety of electric vehicle operation. The layered cable design effectively prevents the cable sheath from bursting due to confined space and cable bending during long-term use when the cable is laid inside the electric vehicle's engine compartment, thus extending the cable's service life and providing excellent flame retardant properties. The cable sheathing equipment provided by this utility model, through the double-layer extrusion die, effectively reduces the risk of compression deformation of the liquid cooling pipe during extrusion, ensuring the cooling efficiency of the cable. Attached Figure Description

[0013] Figure 1 This is a cross-sectional view of an embodiment of the cable according to the present invention.

[0014] Figure 2 This is the braided structure of the explosion-proof tin-plated braided layer of this utility model.

[0015] Figure 3 This is a cross-sectional view of another embodiment of the cable of this utility model.

[0016] Figure 4 This is a cross-sectional view of a cable wrapping equipment mold according to the present invention.

[0017] Figure 5 This is a schematic diagram of another type of cable wrapping equipment mold according to the present invention.

[0018] Figure 6 This is an exploded schematic diagram of another cable sheathing device according to the present invention.

[0019] Figure 7 This is an exploded view of the inner mold area of ​​another cable sheathing device according to this utility model.

[0020] Figure 8 This is a schematic diagram of the inner mold area of ​​another cable covering device according to this utility model. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] As attached Figure 1-2 As shown, the explosion-proof liquid-cooled high-voltage automotive cable involved in this utility model includes a liquid-cooling pipe 1, a bare copper conductor 2, and a wrapping layer 3.

[0023] The liquid cooling pipe 1 is located in the center of the cable. The bare copper conductor 2 consists of several bare copper wires, evenly arranged around the liquid cooling pipe 1. The wrapping layer 3 is overlapped and wrapped around the bare copper conductor 2. An explosion-proof tin-plated braided copper mesh 4 is installed outside the wrapping layer 3. Figure 2 The explosion-proof tin-plated braided copper mesh 4 is woven using tin-plated copper wire. An irradiated cross-linked low-smoke halogen-free flame-retardant polyolefin insulation layer 5 is extruded over the explosion-proof tin-plated braided copper mesh 4. The irradiated cross-linked low-smoke halogen-free flame-retardant polyolefin insulation layer 5 is extruded onto the outside of the explosion-proof tin-plated braided copper mesh 4 using a screw extruder.

[0024] When an electric vehicle is charging, current is transmitted through cables to charge the battery pack. During charging, the cables continuously generate heat, which accumulates inside the vehicle compartment. If the heat cannot be dissipated in time, it will further cause a rapid decrease in the cable's current carrying capacity. This application addresses this issue by installing a liquid-cooled pipe 1 inside the cable conductor, through which a cooling liquid can flow, to dissipate heat from the cable and prevent the heat generated during charging from accumulating inside the vehicle. The bare copper conductor 2 outside the liquid-cooled pipe 1 is a conductive material and serves to transmit current. A layer of wrapping tape is wrapped around the bare copper conductor 2 to tightly bind it, preventing the conductor from becoming loose and affecting current transmission. When cables are laid inside a vehicle, due to the confined space, they inevitably undergo bending and compression. A layer of explosion-proof tin-plated copper mesh is woven outside the wrapping layer 3 to protect the cable's liquid-cooled pipe and conductor, preventing the cable from bursting or cracking after prolonged operation. An irradiated cross-linked low-smoke halogen-free flame-retardant polyolefin insulation layer 5 is extruded over the explosion-proof tin-plated copper mesh, serving as the insulation for the entire cable. This insulation is made of high-temperature resistant and flame-retardant irradiated cross-linked polyolefin material, possessing excellent flame-retardant properties and high elasticity. While providing insulation for the cable, it also reduces the risk of fire. Furthermore, the irradiated cross-linked low-smoke halogen-free flame-retardant polyolefin insulation layer does not release halogen gases or smoke when burning, further protecting the safety of passengers.

[0025] To ensure better flame-retardant insulation performance, the thickness of the polyolefin insulation layer 5 can be increased. Since the cable involved in this application mainly relies on the liquid cooling pipe 1 for cooling, increasing the thickness of the polyolefin insulation layer 5 will not affect the heat dissipation performance of the cable.

[0026] During the extrusion of the polyolefin insulation layer 5, due to its thickness and the desired high density, a high extrusion pressure is required on the screw extruder. However, high extrusion pressure can easily cause deformation of the hollow liquid cooling pipe 1, affecting subsequent cooling efficiency. Therefore, this application provides a cable sheathing device, specifically an extrusion die for a cable extruder.

[0027] As attached Figure 3 , 4 As shown, the extrusion die is a double-layer die m, including an inner die tube m1 and an outer die tube m2. The inner die tube m1 is disposed inside the outer die tube m2 and is coaxial with the outer die tube m2. It is fixed to the inner wall of the outer die tube m2 by a connecting piece m3.

[0028] The inner mold tube m1 and outer mold tube m2 are hollow tubular structures with their inner diameters gradually decreasing from the wire feed end to the wire discharge end. During use, the wire passes through the inner mold tube m1, forming an inner insulating layer 51 on its outer side. Simultaneously, an outer insulating layer 52 is formed under the pressure of the outer wall of the inner mold tube m1 and the inner wall of the outer mold tube m2. Before cooling, the inner insulating layer 51 and the outer insulating layer 52 will adhere to each other to some extent.

[0029] Furthermore, during the extrusion process of the outer insulation layer 52, the compression ratio is greater than that of the inner insulation layer 51. This means the difference / ratio of the inner diameters at both ends of the inner mold tube m1 is less than the difference / ratio of (inner diameter of outer mold tube m2 - outer diameter of inner mold tube m1) at both ends. Consequently, the extrusion pressure of the inner mold tube m1 is lower, resulting in a smaller impact on the hollow liquid cooling tube 1. The thickness of the inner insulation layer is 1 / 5 to 1 / 3 of that of the outer insulation layer.

[0030] Appendix Figure 5 , 6 Figures 7 and 8 show another embodiment of the extrusion die provided in this application. To reduce the manufacturing difficulty of the die, the die in this embodiment is segmented. Specifically, it includes a first outer die segment f1, a second die segment f2, a third outer die segment f3, a fourth outer die segment f4, a first inner die segment f5, and a third inner die segment f6.

[0031] The first outer mold section f1, the second mold section f2, the third outer mold section f3, and the fourth outer mold section f4 are connected by bolts. In the attached figure, the first outer mold section f1, the second mold section f2, and the third outer mold section f3 are connected to the extrusion equipment by long bolts l1, and the fourth outer mold section f4 is connected to the third outer mold section f3 by short bolts l2. The fourth outer mold section f4 can be easily replaced as needed to adjust the outer diameter of the outer insulation layer 52.

[0032] The first outer mold section f1, the second mold section f2, the third outer mold section f3, and the fourth outer mold section f4 are provided with through holes in the center, and their inner diameters are smoothly transitioned.

[0033] The second module segment f2 includes an outer mold ring f21, an inner mold ring f22, and several connecting plates f33. The inner mold ring f22 is disposed inside the outer mold ring f21 and is coaxial with the outer mold ring f21. The outer side of the inner mold ring f22 is fixed and welded to the inner wall of the outer mold ring f21 through the connecting plates f33.

[0034] The first inner mold section f5 and the third inner mold section f6 are connected to both sides of the inner mold ring f22 by a threaded structure. The first inner mold section f5, the inner mold ring f22, and the third inner mold section f6 are provided with a through hole in the center, and their inner diameters are smoothly transitioned, as are their outer diameters.

[0035] Furthermore, the outer contour of the first inner mold section f5 near the feed end is frustum-shaped, with a smaller outer diameter on the side near the feed end, thereby realizing the material separation between the inner and outer molds and the guiding function of the molten material.

[0036] It should be noted that, unless otherwise explicitly specified and limited, terms such as "installation," "connection," "joining," "fixing," and "setting" 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.

Claims

1. An explosion-proof, flame-retardant, liquid-cooled high-voltage automotive cable, characterized in that, It includes a liquid cooling pipe, bare copper conductor, wrapping layer, explosion-proof tin-plated braided copper mesh, and polyolefin insulation layer; wherein the liquid cooling pipe is located in the center of the cable, the bare copper conductor consists of several bare copper wires evenly arranged around the liquid cooling pipe; the wrapping layer overlaps and wraps around the bare copper conductor, and an explosion-proof tin-plated braided copper mesh is set outside the wrapping layer, and an irradiated cross-linked low-smoke halogen-free flame-retardant polyolefin insulation layer is set outside the explosion-proof tin-plated braided copper mesh.

2. A cable coating apparatus for the explosion-proof and flame-retardant liquid-cooled high-voltage automotive cable of claim 1, said cable coating apparatus being a screw extruder, said screw extruder comprising an extrusion die, characterized in that, The extrusion die is a double-layer die, including an inner die tube and an outer die tube. The inner die tube is disposed inside the outer die tube and is coaxial with the outer die tube. It is fixed to the inner wall of the outer die tube by a connecting piece.

3. The cable coating apparatus of claim 2, wherein, The inner and outer mold tubes are hollow tubular structures, with their inner diameter gradually decreasing from the wire feed end to the discharge end.

4. The cable coating apparatus of claim 3, wherein, The extrusion die includes a first outer die section, a second die section, a third outer die section, a fourth outer die section, a first inner die section, and a third inner die section; the first outer die section, the second die section, the third outer die section, and the fourth outer die section are connected by bolts; the second die section includes an outer die ring, an inner die ring, and several connecting plates, the inner die ring is disposed inside the outer die ring and is coaxial with the outer die ring, the outer side of the inner die ring is fixedly connected to the inner wall of the outer die ring by connecting plates, and the first inner die section and the third inner die section are connected to both sides of the inner die ring by threaded structures.

5. The cable coating apparatus of claim 4, wherein, The first outer die section, the second die section, and the third outer die section are connected to the extrusion equipment by long bolts, and the fourth outer die section is connected to the third outer die section by short bolts.

6. The cable coating apparatus of claim 4, wherein, The first outer mold section, the second mold section, the third outer mold section, and the fourth outer mold section are provided with through holes in the center, and their inner diameters are smoothly transitioned; the first inner mold section, the inner mold ring, and the third inner mold section are provided with through holes in the center, and their inner and outer diameters are smoothly transitioned.

7. The cable sheathing equipment according to claim 4, characterized in that, The outer contour of the first inner mold section near the feed end is frustum-shaped, with a smaller outer diameter on the side near the feed end.

Images