Photovoltaic cable with composite multilayer structure
By introducing composite multi-layer structures and sling board connections into photovoltaic cables, the problems of burns and structural instability of users in high-temperature environments are solved, and safety and stability are improved under high-temperature conditions are achieved.
Patent Information
- Application Number
- CN202422336128.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-25
- Publication Date
- 2025-07-25
- Estimated Expiration
- 2034-09-25
AI Technical Summary
Traditional photovoltaic cables lack multi-layer protective structures, which leads to burns the palms of users in high temperature environments, and the internal connection structure of the cable is unstable under high temperature conditions.
A photovoltaic cable with a composite multi-layer structure is designed, including a protective jacket, cable cable core, copper wire protective layer, insulating protective layer, structural protective layer and end protective cover. It is convenient for transfer through threaded connecting shaft and mount plate structure, and protects users and enhances cable stability in high temperature environments.
Effectively prevent users from being scalded under high temperature conditions, while improving the stability and structural strength of the cable in high temperature environments, and avoiding damage to the cable core inside the cable.
Smart Images
Figure CN223155693U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of photovoltaic cables, and specifically relates to a photovoltaic cable with a composite multi-layer structure. Background Art
[0002] At present, clean energy is widely used in industrial industries. As one of the main sources of renewable energy, solar power generation mainly uses photovoltaic solar panels to capture the energy of the sun and convert it into electric energy, and transmits the electric energy through photovoltaic cables.
[0003] The photovoltaic cable is exposed to sunlight for a long time, and the solar energy system is often used under harsh environmental conditions in the desert. In desert and gobi areas, high temperatures will cause the surface temperature of the solar photovoltaic panel to be as high as over 100 °C. Therefore, higher requirements are put forward for the high-temperature resistance and protection performance of the photovoltaic cable.
[0004] The inventor found the following problems in the prior art during the implementation of the present utility model: 1. The traditional photovoltaic cable lacks a multi-layer protection structure inside the cable; 2. When the traditional photovoltaic cable is lifted and transferred, the high temperature on its surface will scald the user's palm. Summary of the Utility Model
[0005] The purpose of the present utility model is to provide a photovoltaic cable with a composite multi-layer structure to solve the problems of the lack of a multi-layer protection structure and the lack of a connection structure for lifting and transferring in the traditional photovoltaic cable proposed in the above background art. To achieve the above purpose, the present utility model provides the following technical solution: A photovoltaic cable with a composite multi-layer structure, including a protective outer sleeve, a group of cable cores are arranged inside the protective outer sleeve, and a terminal protection cover is sleeved on the left end of the protective outer sleeve. A copper wire protection layer is arranged at equal intervals on the outer side of the cable core, and an upper clamping plate is arranged at the upper end of the middle part of the protective outer sleeve.
[0006] A threaded connection shaft is arranged in a groove at the upper middle part of the upper clamping plate, and a circular threaded groove is opened in the upper middle part of the threaded connection shaft. A lower clamping plate is arranged at the bottom end of the upper clamping plate, and rectangular clamping grooves are opened in the middle of the upper surfaces of the front and rear sides of the lower clamping plate. Fixed bolts are arranged inside the rectangular clamping grooves of the lower clamping plate, and a connection buckle is arranged at the upper end of the threaded groove at the upper end of the threaded connection shaft.
[0007] An insulating protection layer is arranged on the inner side of the inner wall of the protective outer sleeve, and the insulating protection layer is arranged on the inner surface of the copper wire protection layer. A heat dissipation connection layer is arranged on the outer side of the cable core, and an insulating clamping ring is arranged on the outer surface of the heat dissipation connection layer. Five arc-shaped through grooves are opened at equal intervals in the middle of the insulating clamping ring, and a structural protection layer is arranged inside each through groove.
[0008] A rotating knob is arranged in a groove in the middle of the end protection cover, and eight pull ropes are wound at equal intervals on the outer surface of the middle outer ring of the rotating knob. Eight rotating pulley sets are arranged at equal intervals on the inner wall of the end protection cover near the outer surface of the end protection cover, and fixed needles are arranged at one end of each pull rope close to the rotating pulley set.
[0009] Further preferably, the middle of the bottom end of the threaded connection shaft is connected to the inner wall of the upper circular groove at the upper end of the upper clamping plate through a bearing, the outer surface of the bottom end of the connection buckle is threadedly connected to the inner wall of the upper threaded groove at the upper end of the threaded connection shaft, and a steel connection ring is connected to the middle of the upper end of the connection buckle through a bearing. The bottom end of the steel connection ring at the upper end of the connection buckle is connected to the inner wall of the middle groove at the upper end of the connection buckle through a bearing.
[0010] Further preferably, circular through threaded grooves are provided in the middle of the bottom ends on both the front and rear sides of the upper clamping plate, circular through threaded grooves are provided in the middle of the left and right sides of the upper rectangular clamping groove at the upper end of the lower clamping plate, and the cross-sectional width of the bottom ends on both the front and rear sides of the upper clamping plate is equal to the cross-sectional width of the inner wall of the upper rectangular clamping groove of the lower clamping plate. The left end of the fixing bolt is threadedly connected with a hexagonal locking nut, and anti-slip gaskets are fixed on the surface of the hexagonal locking nut close to the lower clamping plate. The middle of the left and right ends and the middle of the fixing bolt penetrate and are connected to the inner walls of the threaded grooves on the left and right sides of the rectangular clamping groove of the lower clamping plate and the inner wall of the through groove at the bottom end of the upper clamping plate respectively.
[0011] Further preferably, the cross-sectional diameter of the inner wall on the right side of the end protection cover is equal to the cross-sectional diameter of the outer surface of the left end of the protective outer sleeve. The middle of the left end of the rotating knob is connected to the middle surface of the left end of the end protection cover through a bearing, and the middle of the right end of the rotating knob is connected to the middle of the inner wall of the end protection cover through a sleeved spring. One end of each pull rope close to the center of the end protection cover is fixed to the outer surface of the middle outer ring of the rotating knob.
[0012] Further preferably, the middle of each pull rope is wound around the middle of the rotating pulley set, the middle of the two side surfaces of the rotating pulley set is connected to the inner wall of the end protection cover through a bearing, and the other end of each pull rope is fixed to the middle of one end of the fixed needle close to the rotating pulley set. The middle surface of each fixed needle penetrates and is slidably connected to the outer surface of the outer ring of the inner wall on the right side of the end protection cover.
[0013] Further preferably, spiral anti-slip grooves are provided on the outer surface of the protective outer sleeve, the outer surface and the inner surface of the insulating protective layer are respectively closely attached to the inner wall of the protective outer sleeve and the outer surface of the copper wire protective layer, and the inner wall of the insulating protective layer inside the copper wire protective layer is fixed to the outer surface of the insulating clamping ring through insulating glue.
[0014] Further preferably, both the inner and outer side surfaces of the structural protection layer are fixed to the inner wall of the arc-shaped groove of the insulating snap ring through insulating glue, and the outer side surface of the heat dissipation connection layer is fixed to the inner side surface of the insulating snap ring through insulating glue, and the outer side surfaces of the cable cores are closely attached to the inner wall of the circular groove of the heat dissipation connection layer.
[0015] Compared with the prior art, the beneficial effects of the present utility model are as follows:
[0016] In the present utility model, a copper wire protection layer and a structural protection layer are provided. By arranging the copper wire protection layer inside the protective sleeve, the stability of the overall structure of the cable is improved through the copper wire protection layer. At the same time, an insulating snap ring is arranged inside the protective sleeve, and a plurality of arc-shaped grooves are equidistantly arranged in the middle of the insulating snap ring, and a structural protection layer is arranged inside the grooves. By means of the structural protection layer, when laying the cable, the tightening of the cable is avoided, and the internal tension causes damage to the internal connection cores of the cable.
[0017] In the present utility model, a threaded connection shaft and a connection buckle are provided. By arranging an upper snap plate and a lower snap plate on the upper and lower sides in the middle of the protective sleeve, and arranging fixing bolts through slots on the front and rear sides, a threaded connection shaft can be arranged through a bearing in a slot in the middle of the upper end of the upper snap plate. By threadedly connecting a connection buckle to the middle of the upper end of the threaded connection shaft, when the user transfers the cable, the connection structure can be connected to the middle of the connection buckle, so as to facilitate pulling and transferring the cable irradiated by high temperature. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 is a schematic diagram of the overall structure of the present utility model;
[0019] Figure 2 is a schematic diagram of the side sectional structure of the cable core of the present utility model;
[0020] Figure 3 is a schematic diagram of the overall unfolded structure of the present utility model;
[0021] Figure 4 is a schematic diagram of the enlarged structure of the upper snap plate of the present utility model;
[0022] Figure 5 is a schematic diagram of the enlarged structure of the rotating knob of the present utility model.
[0023] In the figure: 1. Protective sleeve; 2. End protection cover; 3. Cable core; 4. Copper wire protection layer; 5. Upper snap plate; 6. Lower snap plate; 7. Threaded connection shaft; 8. Connection buckle; 9. Structural protection layer; 10. Fixing bolt; 11. Insulating protection layer; 12. Insulating snap ring; 13. Heat dissipation connection layer; 14. Rotating pulley group; 15. Fixed pin; 16. Pulling rope; 17. Rotating knob. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] Next, in combination with the drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the scope of protection of the present invention.
[0025] Please refer to Figures 1 to 5 , the present invention provides a technical solution: a photovoltaic cable with a composite multi-layer structure, including a protective outer sheath 1. Inside the protective outer sheath 1, a group of cable cores 3 are arranged. At the left end of the protective outer sheath 1, a terminal protection cover 2 is sleeved. A copper wire protection layer 4 is arranged at equal intervals on the outer side of the cable core 3. And an upper clamping plate 5 is arranged at the upper middle part of the protective outer sheath 1;
[0026] In the middle of the upper end of the upper clamping plate 5, a threaded connection shaft 7 is arranged with a circular threaded groove opened in the middle of the upper end of the threaded connection shaft 7. At the bottom end of the upper clamping plate 5, a lower clamping plate 6 is arranged. And in the middle of the upper surface of the front and rear sides of the lower clamping plate 6, rectangular clamping grooves are opened. Inside the rectangular clamping grooves of the lower clamping plate 6, fixing bolts 10 are arranged. And at the upper end of the threaded groove at the upper end of the threaded connection shaft 7, a connection buckle 8 is arranged;
[0027] On the inner side of the inner wall of the protective outer sheath 1, an insulating protection layer 11 is arranged. And on the inner surface of the copper wire protection layer 4, an insulating protection layer 11 is arranged. On the outer side of the cable core 3, a heat dissipation connection layer 13 is arranged. And on the outer surface of the heat dissipation connection layer 13, an insulating clamping ring 12 is arranged. Five arc-shaped through grooves are equally spaced in the middle of the insulating clamping ring 12. And inside the through grooves, a structural protection layer 9 is arranged;
[0028] In the middle of the terminal protection cover 2, a rotating knob 17 is arranged with eight pull ropes 16 equally spaced around the outer surface of the middle of the rotating knob 17. At the position of the inner wall of the terminal protection cover 2 close to the outer surface of the terminal protection cover 2, eight rotating pulley groups 14 are equally spaced. And at one end of the pull rope 16 close to the rotating pulley group 14, a fixed needle 15 is arranged.
[0029] In this embodiment, as Figure 2As shown, the middle of the bottom end of the threaded connection shaft 7 is connected to the inner wall of the upper circular groove at the upper end of the upper clamping plate 5 through a bearing, and the outer surface of the bottom end of the connection buckle 8 is threadedly connected to the inner wall of the upper threaded groove of the threaded connection shaft 7. Moreover, a steel connection ring is connected to the middle of the upper end of the connection buckle 8 through a bearing, and the bottom end of the steel connection ring at the upper end of the connection buckle 8 is connected to the inner wall of the middle groove at the upper end of the connection buckle 8 through a bearing. By arranging the threaded connection shaft 7 in the middle of the upper end of the upper clamping plate 5, a connection buckle 8 can be threadedly connected to the upper end of the threaded connection shaft 7, and thus the connection structure can be fixed in the middle of the connection buckle 8 through the connection buckle 8.
[0030] In this embodiment, as Figure 2 shown, circular through threaded grooves are provided in the middle of the bottom ends on both the front and rear sides of the upper clamping plate 5, and circular through threaded grooves are provided in the middle of the left and right sides of the rectangular clamping groove at the upper end of the lower clamping plate 6. Moreover, the cross-sectional width of the bottom ends on both the front and rear sides of the upper clamping plate 5 is equal to the cross-sectional width of the inner wall of the rectangular clamping groove at the upper end of the lower clamping plate 6. The left end of the fixing bolt 10 is threadedly connected to a hexagonal locking nut, and anti-slip gaskets are fixed to the surface of the hexagonal locking nut close to the lower clamping plate 6. Moreover, the middle parts of the left and right ends and the middle part of the fixing bolt 10 are respectively penetrated and connected to the inner walls of the threaded grooves on the left and right sides of the rectangular clamping groove of the lower clamping plate 6 and the inner wall of the through groove at the bottom end of the upper clamping plate 5. By arranging the upper clamping plate 5 and the lower clamping plate 6 in the middle of the protective outer sleeve 1 and fixing and clamping the upper clamping plate 5 and the lower clamping plate 6 in the middle of the protective outer sleeve 1 through the fixing bolt 10.
[0031] In this embodiment, as Figure 5 shown, the cross-sectional diameter of the inner wall on the right side of the end protection cover 2 is equal to the cross-sectional diameter of the outer surface of the left end of the protective outer sleeve 1. Moreover, the middle part of the left end of the rotary knob 17 is penetrated and connected to the surface of the middle part of the left end of the end protection cover 2 through a bearing, and the middle part of the right end of the rotary knob 17 is connected to the middle part of the inner wall of the end protection cover 2 through a sleeved spring. One end of the pull rope 16 close to the center of the end protection cover 2 is fixed to the outer surface of the middle part of the rotary knob 17. By arranging the end protection cover 2 at the end of the protective outer sleeve 1, the end protection cover 2 can protect the internal structure at the end of the protective outer sleeve 1 during the transportation of the protective outer sleeve 1.
[0032] In this embodiment, as Figure 5As shown in the figure, the middle part of the pulling rope 16 is wound around the middle part of the rotating pulley set 14, and the middle parts of both side surfaces of the rotating pulley set 14 are connected to the inner wall of the end protection cover 2 by bearings. Moreover, the other ends of the pulling ropes 16 are fixed to the middle parts of one ends of the fixed pins 15 close to the rotating pulley set 14, and the middle surfaces of the fixed pins 15 penetrate and are slidably connected to the outer surface of the outer ring of the right inner wall of the end protection cover 2. By connecting a pulling rope 16 to the end of the fixed pin 15, the pulling rope 16 can pull the fixed pin 15 to retract into the interior of the end protection cover 2 along the rotating pulley set 14, and the elastic force of the spring at the end of the fixed pin 15 squeezes the fixed pin 15 into the surface interior of the protective outer sleeve 1.
[0033] In this embodiment, as Figure 3 shown, spiral anti-slip grooves are provided on the outer surface of the protective outer sleeve 1, and the outer surface and the inner side surface of the insulating protective layer 11 are respectively closely attached to the inner wall of the protective outer sleeve 1 and the outer surface of the copper wire protective layer 4. Moreover, the inner wall of the insulating protective layer 11 on the inner side of the copper wire protective layer 4 is fixed to the outer surface of the insulating clamping ring 12 by insulating glue. By providing an insulating protective layer 11 inside the protective outer sleeve 1 and a copper wire protective layer 4 in the middle of the insulating protective layer 11, the overall stability of the cable is enhanced.
[0034] In this embodiment, as Figure 3 shown, both the inner and outer side surfaces of the structural protective layer 9 are fixed to the inner wall of the arc-shaped groove of the insulating clamping ring 12 by insulating glue, and the outer surface of the heat dissipation connection layer 13 is fixed to the inner surface of the insulating clamping ring 12 by insulating glue. Moreover, the outer surface of the cable core 3 is closely attached to the inner wall of the circular groove of the heat dissipation connection layer 13. By providing a heat dissipation connection layer 13 outside the cable core 3, when the cable core 3 transmits electric energy, the high temperature outside it can be absorbed and dissipated through the heat dissipation connection layer 13.
[0035] The usage method and advantages of the present utility model: For this photovoltaic cable with a composite multi-layer structure, during use, the working process is as follows:
[0036] As Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5As shown, first, the user can sleeved the end protection cover 2 on the end of the protective jacket 1. At the same time, rotate the rotating knob 17, so that the rotating knob 17 rotates to wind the pulling rope 16 around the middle of the rotating knob 17. Then, the pulling rope 16 rotates along the rotating pulley group 14 and pulls the fixed pin 15, so that the fixed pin 15 retracts into the interior of the end protection cover 2. After inserting the end protection cover 2, release the rotating knob 17, so that the fixed pin 15 is inserted on the outer surface of the end of the protective jacket 1 by the elastic force of the spring at its end. Thus, the end protection cover 2 can be fixed on the end surface of the protective jacket 1;
[0037] When the cable is laid outside, the copper wire protection layer 4 embedded in the protective jacket 1 through the internal insulation protection layer 11 can enhance the overall structural stability of the cable. At the same time, an insulation clamping ring 12 can be fixed inside the insulation protection layer 11, and a structural protection layer 9 is arranged inside the arc-shaped groove of the insulation clamping ring 12. When laying the cable, it can avoid the cable being tightened, resulting in an increase in the internal tension and causing the cable core 3 to break. And a heat dissipation connection layer 13 is arranged outside the cable core 3, and a large amount of heat generated on the surface of the cable core 3 is absorbed and dissipated through the heat dissipation connection layer 13;
[0038] When transferring the cable in a high-temperature environment, the upper clamping plate 5 and the lower clamping plate 6 can be clamped in the middle of the protective jacket 1, and the upper clamping plate 5 and the lower clamping plate 6 are clamped and fixed by the fixing bolt 10. At the same time, the bottom end of the connecting buckle 8 is rotationally fixed to the upper end of the threaded connecting shaft 7 by threading, and the connecting structure is fixed in the middle of the connecting buckle 8. Thus, the user can avoid being scalded by directly contacting the surface of the protective jacket 1.
[0039] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art of this industry should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only the preferred examples of the present invention and do not limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.
Claims
1. A photovoltaic cable with a composite multi-layer structure, comprising a protective outer sheath (1), characterized in that: Inside the protective jacket (1), a set of cable cores (3) is arranged, and a terminal protection cover (2) is sleeved on the left end of the protective jacket (1). A copper wire protective layer (4) is arranged at equal intervals on the outer side of the cable core (3), and an upper clamping plate (5) is arranged at the upper middle part of the protective jacket (1). In the middle of the upper end of the upper clamping plate (5), a threaded connection shaft (7) is arranged with a circular threaded groove opened in the middle of the upper end of the threaded connection shaft (7). A lower clamping plate (6) is arranged at the bottom end of the upper clamping plate (5), and rectangular clamping grooves are opened in the middle of the upper surfaces of the front and rear sides of the lower clamping plate (6). Fixed bolts (10) are arranged inside the rectangular clamping grooves of the lower clamping plate (6), and a connection buckle (8) is arranged at the upper end of the threaded groove of the upper end of the threaded connection shaft (7). An insulating protective layer (11) is arranged on the inner side of the inner wall of the protective jacket (1), and the insulating protective layer (11) is arranged on the inner surface of the copper wire protective layer (4). A heat dissipation connection layer (13) is arranged on the outer side of the cable core (3), and an insulating clamping ring (12) is arranged on the outer surface of the heat dissipation connection layer (13). Five arc-shaped through grooves are opened at equal intervals in the middle of the insulating clamping ring (12), and a structural protective layer (9) is arranged inside each through groove. A rotating knob (17) is arranged with a groove opened in the middle of the terminal protection cover (2), and eight pull ropes (16) are wound at equal intervals on the outer surface of the middle outer ring of the rotating knob (17). Eight rotating pulley groups (14) are arranged at equal intervals on the inner wall of the terminal protection cover (2) near the outer surface of the terminal protection cover (2), and fixed pins (15) are arranged at one ends of the pull ropes (16) close to the rotating pulley groups (14).
2. The photovoltaic cable with a composite multi-layer structure according to claim 1, characterized in that: The bottom middle part of the threaded connection shaft (7) is connected to the inner wall of the upper circular groove of the upper clamping plate (5) through a bearing, and the outer surface of the bottom end of the connection buckle (8) is threadedly connected to the inner wall of the upper threaded groove of the threaded connection shaft (7). And a steel connection ring is connected to the middle of the upper end of the connection buckle (8) through a bearing, and the bottom end of the steel connection ring at the upper end of the connection buckle (8) is connected to the inner wall of the middle groove at the upper end of the connection buckle (8) through a bearing.
3. A photovoltaic cable with a composite multi-layer structure according to claim 1, characterized in that: Circular through threaded grooves are opened in the middle of the bottom ends of the front and rear sides of the upper clamping plate (5), and circular through threaded grooves are opened in the middle of the left and right sides of the upper rectangular clamping grooves of the lower clamping plate (6). And the cross-sectional width of the bottom ends of the front and rear sides of the upper clamping plate (5) is equal to the cross-sectional width of the inner wall of the upper rectangular clamping groove of the lower clamping plate (6). The left end of the fixed bolt (10) is threadedly connected with a hexagonal locking nut, and anti-slip gaskets are fixed on one side surface of the hexagonal locking nut close to the lower clamping plate (6). And the middle parts of the left and right ends and the middle part of the fixed bolt (10) are respectively connected through the inner wall of the threaded grooves on the left and right sides of the rectangular clamping groove of the lower clamping plate (6) and the inner wall of the through groove at the bottom end of the upper clamping plate (5).
4. A photovoltaic cable having a composite multi-layer structure according to claim 1, wherein: The cross-sectional diameter of the inner wall on the right side of the end protection cover (2) is equal to the cross-sectional diameter of the outer surface of the left end outer ring of the protective outer sleeve (1). The middle part of the left end of the rotary knob (17) is connected to the middle surface of the left end of the end protection cover (2) through a bearing. The middle part of the right end of the rotary knob (17) is connected to the middle part of the inner wall of the end protection cover (2) by sleeving a spring. One end of the draw rope (16) close to the center of the end protection cover (2) is fixed to the outer surface of the middle outer ring of the rotary knob (17).
5. A photovoltaic cable having a composite multi-layer structure according to claim 1, characterized in that: The middle parts of the draw ropes (16) are all wound around the middle part of the rotary pulley set (14). The middle parts of the two side surfaces of the rotary pulley set (14) are both connected to the inner wall of the end protection cover (2) through bearings. The other ends of the draw ropes (16) are fixed to the middle part of one end of the fixed pin (15) close to the rotary pulley set (14). The middle surfaces of the fixed pins (15) are all connected to the outer surface of the outer ring of the inner wall on the right side of the end protection cover (2) through through-sliding connections.
6. A photovoltaic cable having a composite multi-layer structure according to claim 1, characterized in that: Spiral anti-slip grooves are provided on the outer surface of the protective outer sleeve (1). The outer surface and the inner surface of the insulating protective layer (11) are respectively in close contact with the inner wall of the protective outer sleeve (1) and the outer surface of the copper wire protective layer (4). The inner wall of the insulating protective layer (11) inside the copper wire protective layer (4) is fixed to the outer surface of the insulating clamping ring (12) by insulating glue.
7. A photovoltaic cable having a composite multi-layer structure according to claim 1, characterized in that: The inner and outer side surfaces of the structural protective layer (9) are both fixed to the inner wall of the arc-shaped groove of the insulating clamping ring (12) by insulating glue. The outer surface of the heat dissipation connection layer (13) is fixed to the inner surface of the insulating clamping ring (12) by insulating glue. The outer surfaces of the cable cores (3) are all in close contact with the inner wall of the circular groove of the heat dissipation connection layer (13).