Production process of liquid-cooled flat cable

Abstract

The invention relates to the field of new energy charging cable production, and discloses a production process of a liquid cooling flat cable, which comprises the following steps of: averagely grouping auxiliary wire cores, signal wire cores and control wire cores, twisting the auxiliary wire cores, the signal wire cores and the control wire cores on a main power wire core, vertically extruding a layer of nylon sheath outside the wire cores, and generating a sleeve effect by utilizing a gap between the nylon sheath and the wire cores to form a cooling channel; a double-port valve is used for replacing a traditional one-to-one cooling pipeline, so that cooling liquid flows back to the charging pile through a single pipeline, the overall contact area of the cooling liquid and each group of wire cores is increased, meanwhile, the overall sectional area of the cable is reduced by 1 / 3, the appearance of the cable is flat, a twisting procedure is omitted, and time and material cost are saved. Production of a novel charging cable which can meet the requirement for large-current rapid charging, has good heat dissipation performance, and meanwhile takes cost effectiveness, flexibility and the characteristic of being easy to store into account is achieved, and the problems that an existing charging cable is limited in overall flexibility and large in bending radius are solved.

Description

Technical Field

[0001] The present invention relates to the field of new energy charging cable production, and in particular to a production process of a liquid-cooled flat cable. Background Art

[0002] With the increasing global awareness of environmental protection and the transformation of energy structure, the new energy vehicle industry has ushered in unprecedented development opportunities. As a key component for energy replenishment of new energy vehicles, charging cables play a vital role in ensuring efficient and safe charging of vehicles. It is not only directly related to charging efficiency and user experience, but also has a profound impact on the popularity of new energy vehicles and the construction of charging infrastructure.

[0003] With the continuous advancement of battery technology and the widespread application of fast charging technology, new energy vehicles have put forward higher requirements for the performance of charging cables. Especially in the context of pursuing higher charging power, the current that the charging cable needs to carry has increased significantly, which directly leads to the aggravation of the conductor heating problem. High temperature will not only reduce the conductive efficiency of the cable and accelerate the aging of the material, but also may cause safety hazards. Therefore, the heat dissipation performance of the charging cable has become one of the key indicators to measure its quality. Effective heat dissipation design can ensure that the cable maintains a low temperature when running at high load, prolonging its service life, while ensuring the safety and stability of the charging process.

[0004] However, the mainstream charging cables on the market currently mostly adopt a circular structure design. Although this design meets the basic electrical transmission needs to a certain extent, it has many limitations. First, due to the large amount of conductors and insulating materials used in circular cables, the production cost is relatively high, which is not conducive to large-scale promotion and application. Secondly, the circular cross-section limits the overall flexibility of the cable and the bending radius is large, which not only increases the difficulty of installation and use, but also brings inconvenience to the user's daily storage. Especially in charging stations or home garages with limited space, the flexibility and easy storage of cables are particularly important.

[0005] Therefore, developing a new charging cable that can meet the needs of high-current fast charging, has good heat dissipation performance, and takes into account cost-effectiveness, flexibility, and easy storage has become a technical problem that needs to be urgently solved in the current new energy vehicle charging field. Summary of the invention

[0006] The present invention aims to provide a production process for a liquid-cooled flat cable, so as to realize the production of a new charging cable that can meet the needs of high-current fast charging, has good heat dissipation performance, and takes into account cost-effectiveness, flexibility and easy storage, thereby improving the problems of limited overall flexibility and large bending radius of existing charging cables.

[0007] To achieve the above object, the present invention adopts the following technical solutions: A production process of a liquid-cooled flat cable, comprising:

[0008] A. Preparation of the main core: Using a conductor with a copper content of ≥99%, and extruding an insulating layer outside the conductor;

[0009] B. Stranding and integrating the control cores: Averagely grouping the auxiliary cores, signal cores, and control cores according to their functions, and then stranding the auxiliary cores, signal cores, and control cores and extruding an insulating sheath outside to form an integrated control core;

[0010] C. Spirally winding the integrated control core outside the main core with a stranding pitch of 15-20 times the core diameter to form a combined core, and preparing two combined cores;

[0011] D. Feeding each combined core into a vertical extruder, vertically extruding a nylon sheath outside the combined core, making the nylon sheath contact with the integrated control core, and forming a cooling channel between the nylon sheath and the main core to form a liquid-cooled combined core;

[0012] E. Preparing a return liquid pipe, arranging two liquid-cooled combined cores side by side and feeding them into the extruder in a triangular shape with the return liquid pipe, and extruding an outer sheath outside to form a liquid-cooled flat cable, and using a flat circular orifice at the discharge orifice of the extruder die;

[0013] F. Cutting off a certain length of the outer sheath at both ends of the liquid-cooled flat cable to expose the liquid-cooled combined cores, drilling holes in the nylon sheaths at both ends of the two liquid-cooled combined cores to connect the inner cooling channels, arranging a three-way pipe between the two ends of the two liquid-cooled combined cores respectively, connecting the two ports of the three-way pipe with the holes on the two liquid-cooled combined cores, connecting one three-way pipe at one end of the liquid-cooled flat cable with the return liquid pipe, and connecting the other three-way pipe with a liquid inlet pipe.

[0014] Preferably, as an improvement, the vertical extrusion temperature of the nylon sheath in step D is controlled at 220-250°C, and the pressure is 15-25 MPa.

[0015] Preferably, as an improvement, the outer diameter of the return liquid pipe selected in step E is less than or equal to one-fourth of the outer diameter of the liquid-cooled combined core.

[0016] Preferably, as an improvement, the major axis dimension of the inner diameter of the flat circular orifice of the die in step E is the sum of the outer diameters of the two liquid-cooled combined cores.

[0017] Preferably, as an improvement, the return liquid pipe in step E is located in the groove formed by the two liquid-cooled combined cores side by side and in contact with each other.

[0018] Preferably, as an improvement, in step F, the three-way pipe is connected to the nylon sheath, the return liquid pipe, and the liquid inlet pipe by hot melting.

[0019] The production process of the liquid-cooled flat cable of the present invention optimizes the vertical extrusion of the nylon sheath and the combined core structure, forming an annular cooling channel between the main core and the nylon sheath, enabling the cooling medium to directly wrap the main core and the integrated control core, significantly increasing the heat dissipation area. At the same time, a double liquid-cooled combined core + return pipe structure arranged in a triangular shape is adopted, and the three are integrated into a flat shape through the flat and round outer sheath extrusion process, maintaining the structural strength while reducing the cable thickness, and improving the softness and bending performance. The hot melt connection between the two ends of the three-way pipe and the nylon sheath and the inlaid design of the return pipe not only reduce the number of connection points but also avoid the space waste problem of multiple parallel pipes in traditional circular cables, achieving the coordinated optimization of efficient heat dissipation and a compact structure.

[0020] The advantages of the present invention include:

[0021] 1. Adopting a flat design with double liquid-cooled combined cores arranged side by side and against each other, the width of the cable in the up and down direction is only 1 / 3 of that of a traditional circular cable (such as a cross-sectional size of 30mm×12mm), reducing the vertical bending radius to ≤5D (D is the outer diameter of the cable), significantly improving the usage flexibility and storage convenience. The flat outer sheath reduces the lateral occupied space, improving the space utilization rate, and is especially suitable for the wiring requirements of compact scenarios.

[0022] 2. The material cost is significantly reduced. By optimizing the conductor structure design, while ensuring the current-carrying capacity, the copper consumption is reduced by 5%. The cross-sectional area of the flat outer sheath is reduced by about 40% compared with that of a circular cable, and the sheath material consumption is reduced by 1 / 3, significantly reducing the production cost.

[0023] 3. The cooling medium directly wraps the main core and the integrated control core, and the heat dissipation area is increased by more than 30% compared with traditional cables. Double-pipe circulation strengthens heat dissipation. The two liquid-cooled combined cores are arranged in parallel, and the total flow rate of the cooling medium ≥30L / min (≥15L / min for a single pipe). The heat that can be carried away within the same time is increased by 60%, and the conductor temperature is stably controlled below 70°C, enabling efficient heat dissipation and temperature reduction.

[0024] 4. The flat structure improves the softness of the cable in the vertical direction, and the number of anti-bending times exceeds 1000 times (about 500 times for traditional circular cables), optimizing the anti-bending performance and extending the service life.

[0025] 5. The double liquid-cooled combined core design enables a single cable to carry a current of more than 500A, meeting the requirements of 800V high-voltage fast charging.

[0026] 6. Signal transmission is integrated. The integrated control core and the main core are co-extruded in the same cooling channel, reducing the number of external wire harnesses, and improving the signal transmission stability by 15%. Description of the Drawings

[0027] Figure 1 It is a cross-sectional view of the liquid-cooled flat cable prepared in the embodiment of the present invention.

[0028] Figure 2 This is a schematic diagram of the cooling medium circulation of the liquid-cooled flat cable prepared in the embodiment of the present invention. Detailed implementation manners

[0029] The following is a further detailed description through specific implementation manners:

[0030] The reference numerals in the accompanying drawings of the specification include: outer sheath 1, cooling pipe 2, main core 3, cooling channel 4, drain three-way pipe 5, integrated control core 6, inlet three-way pipe 7, drain pipe 8.

[0031] Embodiment, a production process of a liquid-cooled flat cable, comprising:

[0032] A. Preparation of the main core: Using a conductor with a copper content of ≥99%, extruding an insulating layer outside the conductor;

[0033] B. Stranding the integrated control core: Averagely grouping the auxiliary cores, signal cores, and control cores according to functions, and then stranding the auxiliary cores, signal cores, and control cores and extruding an insulating sheath outside to form an integrated control core;

[0034] C. Spirally winding the integrated control core outside the main core, with a stranding pitch of 15-20 times the core diameter, to form a combined core, and preparing two combined cores;

[0035] D. Feeding each combined core into a vertical extruder, vertically extruding a nylon sheath outside the combined core, controlling the extrusion temperature at 220-250°C and the pressure at 15-25 MPa, so that the nylon sheath contacts the integrated control core, and a cooling channel is formed between the nylon sheath and the main core to form a liquid-cooled combined core;

[0036] E. Preparing a return pipe, the outer diameter of the return pipe is less than or equal to one-fourth of the outer diameter of the liquid-cooled combined core. After arranging two liquid-cooled combined cores side by side and sending them into the extruder in a triangular shape with the return pipe, the return pipe is located in the groove formed by the two liquid-cooled combined cores in contact with each other side by side, and an outer sheath is extruded outside to form a liquid-cooled flat cable. The outlet of the extruder die uses a flat-round orifice, and the long-axis dimension of the inner diameter of the flat-round orifice of the die is the sum of the outer diameters of the two liquid-cooled combined cores;

[0037] F. Removing a certain length of the outer sheath at both ends of the liquid-cooled flat cable to expose the liquid-cooled combined core. Drilling holes in the nylon sheaths at both ends of the two liquid-cooled combined cores to connect the inner cooling channels. A three-way pipe is arranged between the two ends of the two liquid-cooled combined cores respectively. The two ports at both ends of the three-way pipe are connected to the holes on the two liquid-cooled combined cores. One three-way pipe at one end of the liquid-cooled flat cable is connected to the return pipe, and the three-way pipe at the other end is connected to an inlet pipe. The three-way pipe is connected to the nylon sheath, the return pipe, and the inlet pipe by hot melting.

[0038] The liquid-cooled flat cable produced by this process is Figure 1 , Figure 2 As shown, it includes an outer sheath 1 with an oblong cross-section, and two liquid-cooled combined cores are arranged side by side in the outer sheath 1. The two liquid-cooled combined cores are abutted against each other side by side in the outer sheath 1, and an upper and lower angle space is formed between the two liquid-cooled combined cores in the outer sheath 1. Each liquid-cooled combined core includes a cooling tube 2, and the outer sheath 1 is extruded outside the cooling tubes 2 of the two liquid-cooled wires. A main core 3 is passed through the cooling tube 2, and the main core 3 includes a conductor and an insulating layer. A cooling channel 4 is formed between the main core 3 and the cooling tube 2. An integrated control core 6 twisted on the main core 3 is arranged in the cooling channel 4. The integrated control core 6 includes an insulating sheath, and auxiliary cores, signal cores and control cores are evenly grouped on the inner side of the insulating sheath. A liquid inlet tee 7 is connected between the head ends of the two liquid-cooled combined wire cores, and a liquid discharge tee 5 is connected between the tail ends of the two liquid-cooled combined wire cores. The liquid inlet tee 7 and the liquid discharge tee 5 are respectively located in the upper and lower angle spaces formed between the two liquid-cooled combined wire cores in the outer sheath 1. The liquid discharge tee 5 is connected to a liquid discharge pipe 8, and the liquid discharge pipe 8 is located in the angle space formed between the two liquid-cooled combined wire cores in the outer sheath 1. The liquid inlet tee 7 and the liquid discharge tee 5 are both connected to the cooling channel 4, and a sealing rubber ring is provided at the connection between the liquid inlet tee 7, the liquid discharge tee 5 and the cooling pipe 2 as a sealing member. The cooling medium enters the cooling channel 4 at the head ends of the two liquid-cooled combined wire cores through the liquid inlet tee 7 to cool the main wire core 3 and the integrated control wire core 6, and then is discharged from the liquid discharge tee 5 at the tail ends of the two liquid-cooled combined wire cores.

[0039] The flow rate of the cooling medium in the cooling channel 4 is greater than or equal to 15 L / min.

[0040] The specific implementation process is as follows: In actual application, this product is applied to new energy charging piles, the integrated control core 6 is twisted outside the main core 3, and then the two are placed in the cooling tube 2 as a whole. The two liquid-cooled combined cores are connected at the head end and the tail end through a three-way structure. The three-way structure makes the connection points fewer, and each connection point is easier to ensure the connection quality, and the risk of leakage is lower. In this way, the cooling medium of the two liquid-cooled combined cores is water, and the cooling medium of the two liquid-cooled combined cores is uniformly discharged through the drain pipe 8, so that the cooling medium flows back to the charging pile through a single pipeline. In this way, the overall contact area of ​​the cooling medium with each group of cores in the cooling channel 4 is significantly increased, and the circulation of the cooling medium is accelerated at the same time. The cooling medium can take away more heat at the same time when the double-tube circulation is in progress. In addition, by adopting a flat structure, the upper and lower widths are reduced, which improves the softness of the product in the upper and lower directions, so that it has a smaller bending radius, which is convenient for use and storage. Under the premise of ensuring structural strength, the anti-bending performance is greatly improved, and the service life is extended.

[0041] The liquid-cooled flat cable products produced by adopting the technical solution of the present invention have the advantages of good cooling effect, high softness, convenient use and storage, long service life, etc. under the same structural strength compared with the products of the prior art.

[0042] The above are only embodiments of the present invention. Specific technical solutions and / or common knowledge such as characteristics well known in the art are not described in detail herein. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the implementation effect of the present invention and the practicability of the patent. The protection scope required by this application shall be subject to the content of its claims, and the specific implementation manners and the like recorded in the specification can be used to interpret the content of the claims.

Claims

1. A production process for a liquid-cooled flat cable, characterized in that: include: A. Preparation of main line core: Use conductor with copper content ≥99% and extrude insulation layer outside the conductor; B. Twisted integrated control core: The auxiliary core, signal core, and control core are evenly grouped according to their functions, and then the auxiliary core, signal core, and control core are twisted and wrapped with an insulating sheath on the outside to form an integrated control core; C. The integrated control core is spirally wound around the main core, with a twisting pitch of 15-20 times the core diameter to form a combined core. Two combined cores are prepared; D. Feed each combined wire core into a vertical extruder, and vertically extrude a nylon sheath outside the combined wire core, so that the nylon sheath contacts the integrated control wire core, and a cooling channel is formed between the nylon sheath and the main wire core to form a liquid-cooled combined wire core; E. Prepare the liquid return pipe, place two liquid-cooled combined wire cores side by side and feed them into the extruder in a herringbone shape with the liquid return pipe, extrude the outer sheath on the outside to form a liquid-cooled flat cable, and use an oblate outlet for the extruder die; F. Cut off a certain length of the outer sheath at both ends of the liquid-cooled flat cable to expose the liquid-cooled combined wire core, drill holes on the nylon sheaths at both ends of the two liquid-cooled combined wire cores to connect the inner cooling channel, and set a tee between the two ends of the two liquid-cooled combined wire cores. The two ends of the tee are connected to the holes on the two liquid-cooled combined wire cores. The tee at one end of the liquid-cooled flat cable is connected to the liquid return pipe, and the tee at the other end is connected to the liquid inlet pipe.

2. The production process of a liquid-cooled flat cable according to claim 1, characterized in that: In the step D, the vertical extrusion temperature of the nylon sheath is controlled at 220-250° C. and the pressure is 15-25 MPa.

3. The production process of a liquid-cooled flat cable according to claim 2, characterized in that: The outer diameter of the liquid return pipe selected in step E is less than or equal to one quarter of the outer diameter of the liquid-cooled combined wire core.

4. The production process of a liquid-cooled flat cable according to claim 3, characterized in that: In the step E, the major axis dimension of the inner diameter of the oblate opening of the mold is the sum of the outer diameters of the two liquid-cooled combined wire cores.

5. The production process of a liquid-cooled flat cable according to claim 4, characterized in that: In step E, the liquid return pipe is located in a groove formed by two liquid-cooled combined wire cores being placed side by side.

6. The production process of a liquid-cooled flat cable according to claim 5, characterized in that: In step F, the three-way pipe and the nylon sheath, the liquid return pipe and the liquid inlet pipe are all connected by hot melting.

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