A DC charging gun cable and its connecting device

Abstract

The utility model discloses a DC charging gun cable and a connecting device thereof, comprising an outer protective layer, wherein a plurality of power cables are evenly arranged on the inner side of the outer protective layer, the plurality of power cables are arranged in a circular ring shape, and a grounding cable, an auxiliary power cable and a signal cable are respectively arranged in the annular space surrounded by the plurality of power cables; the cable of the present invention adopts a lightweight design scheme of a multi-core power cable, the overall cable has a small bending radius, strong flexibility, and a small overall weight, the weight is reduced by about 0.7Kg / M, the outer diameter of the cable is thin, the diameter is reduced by about 10mm, it is easy to install and has a good heat dissipation effect; the connection part of the cable and the terminal of the present invention adopts an ultrasonic welding connection method; the charging interface part has a low temperature rise at a large load current, and compared with the conventional double-core cable, the temperature rise is reduced by about 10K, the charging is more stable, and the problem of over-temperature tripping is not easy to occur.

Description

Technical Field

[0001] The utility model relates to the technical field of charging guns, in particular to a DC charging gun cable and a connecting device thereof. Background Art

[0002] With the popularity and development of electric vehicles, the construction of charging infrastructure has become particularly important. DC fast charging technology has become an important part of electric vehicle charging technology because it can fully charge electric vehicle batteries in a short time. At present, DC fast charging is mainly achieved through high-power DC charging guns, which are connected to DC charging piles to quickly charge electric vehicle batteries through high currents.

[0003] The conventional DC charging gun in the prior art mainly has the following two technical solutions:

[0004] Double-core power cable solution: Use double-core cables with large cross-sectional area for power transmission.

[0005] Mechanical crimping connection method: The cable and terminal are connected together through mechanical crimping technology.

[0006] Disadvantages of dual-core power cable solution:

[0007] 1. Poor flexibility: the current requirement is 250A, and the cross-sectional area of ​​the power cable needs to be 70-80mm 2 Generally, the power cables are combined side by side, and the outer sheath of the power cable and the combined cable is added. The outer diameter of the cable is generally about φ40mm. Due to the large cross-sectional area of ​​the cable, the cable is not flexible enough and the operation is inconvenient;

[0008] 2. Poor heat dissipation performance: A single large-section cable has poor heat dissipation performance and is prone to overheating when loaded with large currents;

[0009] 3. The cable is heavy and not suitable for use: The outer diameter of the cable is generally about 40mm, and the extra space needs to be filled with fillers, so the cable weight is not less than 3Kg / M.

[0010] Disadvantages of mechanical crimping connection:

[0011] 1. The crimped cable is not easy to fix due to its cylindrical shape. After the terminal is connected to the cable, it is easy to rub against the seal during use, thereby reducing the service life of the product.

[0012] 2. The contact resistance at the connection between the crimped cable and the terminal is high, which causes the temperature to rise. In a large-load charging environment, it is easy to trigger a charging alarm due to overtemperature, affecting the safety and user experience.

[0013] To this end, a DC charging gun cable and a connecting device thereof are proposed. Summary of the invention

[0014] The purpose of the utility model is to provide a DC charging gun cable and a connecting device thereof to solve the problems raised in the above-mentioned background technology.

[0015] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a DC charging gun cable, comprising an outer protective layer, a plurality of power cables are evenly arranged on the inner side of the outer protective layer, the plurality of power cables are arranged in a circular ring shape, and a grounding cable, an auxiliary power cable and a signal cable are respectively arranged in the annular space surrounded by the plurality of power cables.

[0016] Preferably, the number of the power cables is eight, including four positive cables and four negative cables, and the positive and negative cables are symmetrically distributed.

[0017] Preferably, the power cable is made of bare copper and is protected by rubber material on the outside.

[0018] Preferably: the gaps between the power cable, the grounding cable, the auxiliary power cable and the signal cable are provided with paper cotton fillers.

[0019] A connection device for a DC charging gun cable using any one of the above-mentioned items includes two wiring terminals; multiple strands of the power cable are respectively welded to the two wiring terminals, and a connecting block is provided at the welding point between the power cable and the wiring terminals.

[0020] Preferably, a mounting frame is installed on the outer side of the wiring terminal, and a contoured fixing groove of the connecting block is provided on the mounting frame.

[0021] Preferably: a sealing ring is installed between the mounting frame and the wiring terminal.

[0022] Compared with the prior art, the beneficial effects of the utility model are:

[0023] 1. The cable of the present invention adopts a lightweight design of a multi-core power cable, with a small overall cable bending radius, strong flexibility, and a small overall weight, which is reduced by about 0.7Kg / M. The cable has a thin outer diameter, which is reduced by about 10mm, is easy to install, and has a good heat dissipation effect;

[0024] 2. The connection between the cable and the terminal of the present invention is made by ultrasonic welding; the temperature rise of the charging interface is low when the load current is large. Compared with the conventional double-core cable, the temperature rise is reduced by about 10K, the charging is more stable, and the over-temperature tripping problem is not likely to occur;

[0025] 3. The present invention reduces the rotation of the terminal installation cavity during use, reduces the peeling force continuously applied to the welding surface, reduces the friction between the terminal and the sealing member, and prolongs the service life of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a schematic diagram of the structure of the utility model cable;

[0027] Figure 2 It is a schematic diagram of the cable connection structure of the utility model;

[0028] Figure 3 It is the temperature rise diagram of the conventional crimping terminal of the utility model;

[0029] Figure 4 This is the temperature rise diagram of the terminal of the utility model.

[0030] In the figure: 1. Outer protective layer; 2. Power cable; 3. Grounding cable; 4. Auxiliary power cable; 5. Signal cable; 6. Wiring terminal; 7. Connection block; 8. Sealing ring; 9. Contoured fixing groove; 10. Mounting frame. DETAILED DESCRIPTION

[0031] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0032] Example

[0033] See also Figure 1-4 The utility model provides a technical solution: a DC charging gun cable, comprising an outer protective layer 1, a plurality of power cables 2 are evenly arranged on the inner side of the outer protective layer 1, the plurality of power cables 2 are arranged in a circular ring shape, and a grounding cable 3, an auxiliary power cable 4 and a signal cable 5 are respectively arranged in the annular space surrounded by the plurality of power cables 2.

[0034] like Figure 1 As shown: the number of power cables 2 is eight, including four positive cables and four negative cables, the positive and negative cables are symmetrically distributed, the power cables 2 are made of bare copper, and are protected by rubber material on the outside; through the above settings, the cable arrangement is optimized, the internal space of the cable is compressed, the use of filling materials in the cable is reduced, and the overall weight of the cable is reduced. At the same time, due to the optimized arrangement, the wire diameter of the cable is reduced, the bending radius of the cable is smaller, the cable is easier to assemble during installation, the burden of use is reduced during use, and the movement of the cable is more convenient.

[0035] The main power cable 2 is split into four strands and evenly distributed around the outer periphery of the total cable. Compared with the traditional single-strand large-section power cable structure, the outer surface area of ​​the cable conductor is increased by 2 times, which has a better heat dissipation effect. Figure 3 and Figure 4 As shown, it can effectively improve the heat dissipation capacity of the cable when it is loaded with large current, significantly reduce the temperature rise of the cable when it is loaded, reduce the risk of power outage, improve the safety of use and improve the user experience.

[0036] like Figure 1As shown: the gaps between the power cable 2, the grounding cable 3, the auxiliary power cable 4 and the signal cable 5 are provided with paper cotton fillers.

[0037] A connecting device for a DC charging gun cable adopts any of the above items, including two terminal blocks 6; multiple power cables 2 are respectively welded to the two terminal blocks 6, and a connecting block 7 is provided at the welding point between the power cable 2 and the terminal block 6; through the above arrangement, the insulating sheaths at the ends of the four positive and negative cables of the power cable 2 after being split are stripped off, exposing the bare copper cable, and each copper wire is arranged in a "field" shape and pressed on the welding plane of the terminal block 6 with a tool; then, the four cables are welded by ultrasonic welding equipment to merge into a connecting block 7 to complete the connection between the cable and the terminal.

[0038] like Figure 2 As shown: a mounting frame 10 is installed on the outer side of the terminal block 6, and a contoured fixing groove 9 of the connecting block 7 is provided on the mounting frame 10, and a sealing ring 8 is installed between the mounting frame 10 and the terminal block 6; through the above settings, it is known that ultrasonic welding has the advantage of small connection resistance compared with mechanical crimping, but the corresponding welding surface increases the requirement for peeling force, which prevents the cable from being "peeled off" from the welding surface when the contact surface is subjected to normal force, thereby causing connection failure.

[0039] However, since the charging gun requires the cable to be bent inside the gun body during installation, if the bending direction is parallel to the normal of the welding surface of the terminal and the cable, the continuous stress generated after the cable itself is bent will exert a peeling force on the welding surface, which may reduce the product's service life.

[0040] To solve this problem, the present invention improves the traditional clamping type fixed pressure plate: according to the size after welding, the pressure plate of the present invention is adaptively designed: the place where the pressure plate and the terminal are buckled is made into a contoured installation cavity, so that the terminal can only be installed on the gun head with the normal direction of the welding surface perpendicular to the bending direction, thereby reducing the peeling force on the welding surface inside the gun body. At the same time, the contoured structure fixes the terminal in the installation cavity, which can prevent the power cable from rotating due to frequent movement during use, reduce the friction between the sealing part of the gun body and the terminal, and increase the service life of the product.

[0041] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A DC charging gun cable, comprising an outer protective layer (1), characterized in that: A plurality of power cables (2) are evenly arranged on the inner side of the outer protective layer (1), the plurality of power cables (2) are arranged in a circular ring shape, and a grounding cable (3), an auxiliary power cable (4) and a signal cable (5) are respectively arranged in the annular space surrounded by the plurality of power cables (2).

2. A DC charging gun cable according to claim 1, characterized in that: The number of the power cables (2) is eight, including four positive cables and four negative cables, and the positive and negative cables are symmetrically distributed.

3. A DC charging gun cable according to claim 2, characterized in that: The power cable (2) is made of bare copper and is externally protected by rubber material.

4. A DC charging gun cable according to claim 1, characterized in that: The gaps between the power cable (2), the grounding cable (3), the auxiliary power cable (4) and the signal cable (5) are provided with paper cotton fillers.

5. A connection device for a DC charging gun cable according to any one of claims 1 to 4, characterized in that: comprising two connecting terminals (6); The multiple strands of the power cables (2) are respectively welded to two wiring terminals (6), and a connecting block (7) is provided at the welding point between the power cables (2) and the wiring terminals (6).

6. A connection device for a DC charging gun cable according to claim 5, characterized in that: A mounting frame (10) is installed on the outer side of the wiring terminal (6), and a profiling fixing groove (9) of the connecting block (7) is provided on the mounting frame (10).

7. A connection device for a DC charging gun cable according to claim 6, characterized in that: A sealing ring (8) is installed between the mounting frame (10) and the wiring terminal (6).

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