Flexible large-current lead

Abstract

The utility model discloses a flexible large-current lead which comprises two ends and a middle section, and the rigidity of the two ends is larger than that of the middle section. The wire is further provided with an insulating sheath, the insulating sheath is annular and continuously covers the electrified part except the electric contact, the insulating sheath tightly wraps the crimping part of the wiring terminal, and the insulating sheath is in the shape that the walls of the two ends are thick and gradually become thinner towards the middle section. The utility model can be applied to a connecting line between a trolley bus current collection head and a trolley pole, a connecting line between a pantograph head and a fixed cable and the like, and other connecting working conditions requiring spatial three-dimensional displacement, stronger vibration and large-current conduction at the same time.

Description

TECHNICAL FIELD

[0001] The utility model relates to mechanical and electrical fields, and it is a soft electric connection part, in particular to a large current connecting wire for current collector, especially to a flexible power cable used for electrically connecting the current collector head and the vehicle in the trolleybus current collector. BACKGROUND

[0002] The current collector head is carried by the end of the current collector rod on the trolleybus current collector, and the sliding shoe of the current collector head contacts the contact line to realize electric connection. When the current collector head works, the sliding shoe has pitching and horizontal rotation movements, and it needs to provide a current of up to 90 to 300 A for the vehicle. The current needs to be transmitted to the current collector rod through a small flexible wire and then to the vehicle.

[0003] Due to the harsh working conditions, the wire not only transmits a large current, but also bears three-dimensional, repeated displacement, torsion, bending, and even the vibration of the contact line and the current collector, thereby causing periodic swinging and shaking of the wire. The known small flexible wire often breaks near the root of the wire terminal, causing failure. SUMMARY

[0004] The technical problem to be solved by the utility model is to provide a flexible large current wire to avoid breaking from the wire terminal root.

[0005] The specific technical scheme for solving the above technical problem of the utility model is:

[0006] The wire includes a wire terminal and a flexible electric conductor, the wire terminal is crimped at both ends of the flexible electric conductor, the flexible electric conductor includes two ends and a middle segment, and the rigidity of the two ends is greater than that of the middle segment.

[0007] The utility model has the beneficial results that: while meeting the electrical conductivity requirements, the strength of the crimping part of the wire terminal and the flexible electric conductor and the transition section of the wire terminal and the electric conductor is high, the softness of the cable as a whole is ensured due to the mechanical strength weakening treatment of the middle segment of the electric conductor, and under the same external conditions of large and complex displacement at both ends of the wire, the cable is not easy to break and the service life is improved.

[0008] The utility model also considers the reliability problem of the electric connection between the sliding shoe and the current collector rod under high-speed conditions (80 km / h) of the electric heavy truck, because the speed of the electric heavy truck is much higher than that of the trolleybus. The actual driving speed of the trolleybus is about 30 km / h, and the known electric heavy truck is designed at a speed of 80 km / h. The faster the vehicle speed, the more serious the shaking of the current collector head. The improved flexible large current wire can adapt to the high-speed operation of the electric heavy truck and improve the working stability.

[0009] The essence of this utility model is to strengthen the mechanical strength of the cable at the root where stress is concentrated and prone to breakage, and weaken the mechanical strength of the middle section of the cable where stress is less and not prone to breakage to ensure flexibility; it not only ensures the flexibility of the cable, but also ensures its electrical conductivity and extends its lifespan; it can also be used to modify and manufacture cables of existing specifications.

[0010] Furthermore, the mechanical strengthening measure of the electrical conductor material is that the wire diameter in the middle section is smaller than the wire diameter at both ends;

[0011] Furthermore: a bending stress buffer structure is provided at both ends of the conductor in the forward direction. The bending stress buffer structure is used to constrain the bending degree of the conductor at that position and to disperse and reduce the bending stress borne by the conductor when bending at that position. The buffer structure is, for example, a buffer spring, which can be provided in segments around both ends of the conductor or integrally around the outer periphery of the conductor.

[0012] Furthermore: the electrical conductor is composed of several sub-conductors connected in parallel, and the sub-conductors are composed of a combination of multiple single wires or multiple small-diameter stranded wires connected in parallel;

[0013] Furthermore: the electrical conductor is composed of small-gauge stranded wires with two different twist directions, avoiding the problem of inconsistent torsional resistance between the forward and reverse twist directions due to the twist direction;

[0014] Furthermore: the electrical conductor is also provided with an insulating sheath; the insulating sheath tightly wraps the crimping part of the terminal, further improving the connection strength between the electrical conductor and the terminal; the insulating sheath is a tube with a wall thickness at both ends greater than that in the middle section, and the insulating sheath gradually thins from both ends to the middle section.

[0015] Furthermore: the terminal block and the electrical conductor are fixed together by crimping or welding, or the conductor body is directly formed. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall shape of the conductor;

[0017] Figure 2 This is a schematic diagram of the basic structure of a conductor;

[0018] Figure 3 This is a schematic diagram of a quarter section of the insulating sheath;

[0019] Figure 4 A schematic diagram of a conductor with an insulating sheath;

[0020] Figure 5 This is a schematic diagram of a buffer spring;

[0021] Figure 6 A schematic diagram of the wires for setting the insulating sheath and buffer spring;

[0022] The following is a list of component names represented by the reference numerals in the attached diagram:

[0023] 1. Terminal block; 2. Flexible conductor; 3. Insulating sheath; 4. Buffer spring. Detailed Implementation

[0024] The principles and features of this utility model are described below with reference to the accompanying drawings. The examples given are only for explaining this utility model and are not intended to limit the scope of this utility model.

[0025] like Figure 1 The image shown is a rendering of the finished product of this utility model.

[0026] Example 1:

[0027] like Figure 2 As shown, a flexible high-current conductor includes a flexible conductor 2 and terminals 1 at both ends of the flexible conductor 2. The flexible conductor 2 is a flexible multi-core stranded copper cable made of reinforced copper material, such as chromium zirconium copper wire or beryllium copper wire, which are copper alloys with reinforcing alloy phases. These two copper alloys are preferred because they have high strength and high conductivity, and can withstand greater mechanical stress. The terminals are crimped to both ends of the copper cable. There is a sudden change in cross-section at the junction of the terminals and the copper cable. The abrupt change in stiffness at this point will cause stress concentration. Under long-term bending, fatigue failure and fracture will occur at this point. Higher strength materials can withstand greater mechanical stress and can extend the life of this point. Since a high-strength material is used for the conductor, the overall stiffness of the copper cable will be increased, making it less prone to bending and twisting. Therefore, the middle section of the flexible conductor 2, i.e., section L shown in the figure, is weakened. The weakening treatment refers to annealing the section L to soften and eliminate its internal stress. The length of section L is preferably 30% to 80% of the total length of the flexible conductor 2.

[0028] Furthermore, an appropriate number of alloy-reinforced copper monofilaments or small-diameter stranded wires are combined to form a copper cable, which meets the current conduction requirements and also satisfies the purpose of this utility model; at the same time, its torsional stiffness is lower than that of a copper cable made of stranded wires. The small-diameter stranded wires can also be made in different directions of rotation, and the two are used together to further ensure that the torsional stiffness of the copper cable is consistent in both directions of rotation.

[0029] Figures 3 to 6 The mechanical structure reinforces the junction between the terminal block and the copper cable; the insulating sheath 3 is a hollow silicone rubber tube that is thick at both ends and thin in the middle; it is fitted tightly around the flexible conductor 2 to dampen the vibration of the conductor during use and also provides insulation protection; the thicker ends can bear part of the bending moment of the copper cable, reducing the bending moment load borne by the copper cable.

[0030] Furthermore, a tightly wound spiral buffer spring 4 is attached to the junction of the copper cable and the terminal block. When a bending moment occurs, the buffer spring 4 bends more evenly, further dispersing the stress generated by the bending moment and reducing the bending moment load borne by the copper cable.

[0031] Example 2:

[0032] The electrical connection flexible busbar is made of multiple high-strength copper foils stacked together. The terminal 1 is made of multiple high-strength copper foils stacked and welded together. The middle section is annealed to reduce the strength of the middle section and make the bending moment of the connection busbar smaller.

[0033] Example 3:

[0034] Unlike Example 1, in this example, the weakening of the middle section of the flexible conductor 2 is achieved by reducing the diameter of the middle section cable, that is, the diameter of the middle section is smaller than the diameter of the two ends. The smaller diameter can obtain better flexibility.

[0035] Furthermore, both ends can be heat-treated and quenched. Quenching can increase the hardness of both ends and further improve the strength of the connection terminals.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A flexible high-current conductor, characterized in that: The wire includes terminals and a flexible conductor. The flexible conductor has terminals crimped to both ends. The flexible conductor includes two ends and a middle section. The stiffness of the two ends is greater than that of the middle section.

2. The flexible high-current conductor according to claim 1, characterized in that: The wire diameter in the middle section is smaller than that at both ends.

3. The flexible high-current conductor according to claim 1, characterized in that: The conductor is fixedly provided with bending stress buffer structures at both ends. The bending stress buffer structures are used to constrain the bending degree of the conductor at that position and to disperse and reduce the bending stress borne by the conductor when it bends.

4. The flexible high-current conductor according to claim 1, characterized in that: The electrical conductor is composed of several sub-conductors connected in parallel, and the sub-conductors are single-wire or small-diameter stranded wires.

5. The flexible high-current conductor according to claim 4, characterized in that: The electrical conductor is composed of small-gauge stranded wires with two different twist directions.

6. The flexible high-current conductor according to claim 1, characterized in that: The electrical conductor is also provided with an insulating sheath, which is a tubular shape with a wall thickness at both ends greater than that in the middle section, and the wall thickness of the insulating sheath gradually decreases from both ends to the middle.

7. The flexible high-current conductor according to claim 1, characterized in that: The flexible conductor is made of chromium zirconium copper or beryllium copper.

8. The flexible high-current conductor according to any one of claims 1-7, characterized in that: The middle section undergoes heat treatment annealing, and the two ends undergo heat treatment quenching.

9. The flexible high-current conductor according to any one of claims 1-7, characterized in that: The terminals are fixed together with the electrical conductor by crimping or welding, or the conductor body is directly formed.

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