CN115831451B

CN115831451B - Anticorona power cable for photovoltaic

Info

Publication number: CN115831451B
Application number: CN202310112836.XA
Authority: CN
Inventors: 曹奎红; 赵国辉; 王玉龙; 郭占卿; 赵建国; 王现林; 邢成安; 赵宁; 赵沛
Original assignee: Eastern Crosslink Power Cable Co ltd
Current assignee: Eastern Crosslink Power Cable Co ltd
Priority date: 2023-02-15
Filing date: 2023-02-15
Publication date: 2023-04-28
Anticipated expiration: 2043-02-15
Also published as: CN115831451A

Abstract

The invention discloses an anticorona power cable for photovoltaic, which relates to the field of cables and comprises a cable body, wherein two groups of cable bodies are arranged, each group of cable body consists of four conductors which are distributed in an annular equidistant manner, and the outer side of each conductor is wrapped with an insulating layer; the anti-corona mechanism is arranged on the outer side of the conductor and used for weakening the adverse effect of corona on the conductor, and comprises an inner shielding layer and an outer shielding layer, wherein the inner shielding layer is wrapped on the outer side of the insulating layer respectively, the outer shielding layer is wrapped on the outer side of the inner shielding layer respectively, and the inner shielding layer and the outer shielding layer are formed by mixing and processing polyvinyl chloride and silicon oxide. Can realize through setting up the support in order to make the gap between the conductor in outer shielding layer inside, set up first gasbag between the support, can absorb the heat that the conductor sent through the gasbag to improve the radiating effect of conductor, and when the conductor temperature is too high and spontaneous combustion, first gasbag is heated the damage and is spouted inert gas, helps putting out a fire.

Description

Anticorona power cable for photovoltaic

Technical Field

The invention relates to the field of cables, in particular to an anticorona power cable for photovoltaic.

Background

The photovoltaic cable is often exposed to sunlight, especially in hot summer, and the photovoltaic cable is easy to generate corona discharge phenomenon under the action of high temperature and ultraviolet radiation, and the corona can generate thermal effect to raise the local temperature in a wire in the cable, so that the cable is easy to fire and burn out a circuit.

The Chinese patent with the publication number of CN211087978U discloses an anti-electromagnetic corona-resistant power cable, provides a technical scheme, and through outer flame retardant coating and interior flame retardant coating for fire-resistant mica tape and perchloroethylene layer, makes the cable have good fire behavior, and through outer sheath for insulating grade PVC sheath, makes the cable have outside protection, can effectively play anti-electromagnetic effect through the shielding net, and through outer shielding layer and interior shielding layer for the organosilicon resin layer, can effectually be corona-resistant, the protection inner conductor is not influenced.

Although the corona-resistant effect can be realized in the above-mentioned patent, set up multilayer inoxidizing coating in the conductor outside, cause the internal conductor heat dissipation slower easily, especially in hot summer, under long-time insolateing, conductor internal temperature risees gradually, again because the existence of multilayer inoxidizing coating for the temperature of internal conductor is high, thereby causes the cable damage easily.

For this purpose, an anticorona power cable for photovoltaic use is proposed.

Disclosure of Invention

The invention aims to provide an anticorona power cable for photovoltaic, which solves the problems in the background technology.

In order to solve the problems, the invention adopts the following technical scheme.

An anticorona power cable for photovoltaic use comprising

The cable comprises cable bodies, wherein two groups of cable bodies are arranged, each group of cable bodies consists of four annular conductors distributed at equal intervals, and the outer side of each conductor is wrapped with an insulating layer;

the corona resistant mechanism is arranged on the outer side of the conductor and used for weakening the adverse effect of corona on the conductor, and comprises an inner shielding layer and an outer shielding layer, wherein the inner shielding layer is respectively wrapped on the outer side of the insulating layer, the outer shielding layer is wrapped on the outer side of the inner shielding layer, and the inner shielding layer and the outer shielding layer are formed by mixing and processing polyvinyl chloride and silicon oxide;

the inside horizontal equidistance fixedly connected with a plurality of support of outer shielding layer, four round holes that can supply the conductor to pass are offered to the annular equidistance of support outer edge position, can make there be the space in order to improve the radiating effect between the conductor through the setting of support.

Further, a first air bag is fixedly connected between the adjacent brackets, and inert gas is filled in the first air bag.

Further, the outside horizontal equidistance fixedly connected with a plurality of solid fixed ring of outer shielding layer, adjacent annular equidistance fixedly connected with a plurality of pillar between the solid fixed ring, the central point of pillar puts outwards arching, and the pillar is ductile metal material.

Further, the outer side of the fixing ring is wrapped with a protection layer, two groups of cable bodies are fixedly connected with the sealing heads at the ends, close to each other, of the protection layer, and one end, close to the sealing heads, of the protection layer is fixedly connected with the sealing heads.

Further, the outer sides of the two groups of one ends of the cable bodies, which are close to each other, are provided with a housing, the right ends of the conductors on the left side inside the housing are fixedly connected with first binding posts, the left ends of the conductors on the right side inside the housing are fixedly connected with second binding posts, the first binding posts penetrate through to the right side of the sealing head, the second binding posts penetrate through to the left side of the sealing head, and the first binding posts are matched with the second binding posts.

Further, the fixed adapter sleeve in the head outside of the inside left side of housing is equipped with first joint, the right flank of first joint is outside along the annular equidistance fixedly connected with four inserted bars in position, the fixed cover in annular lateral surface of the head on the inside right side of housing is equipped with the second joint, the right flank of second joint is outside along the annular equidistance fixedly connected with four can supply inserted bars male cartridge, and the one side fixed connection spring of inserted cartridge inside keeping away from the inserted bar.

Further, the left side annular equidistant fixedly connected with two articulated seats of first joint, articulated respectively have the jack catch on the articulated seat.

Further, set up the frame plate above the jack catch, two push rods of symmetry fixedly connected with around the frame plate lower extreme, symmetry fixedly connected with two carrier plates on the housing front and back inside wall of frame plate top, the spout that the cross-section is T shape structure has been seted up to the position that the carrier plate lower extreme is close to the left side, sliding connection has the slide rather than the matching in the spout, the lower extreme of slide is respectively with frame plate up end fixed connection.

Further, the support plate up end is equipped with the second gasbag respectively, the common fixedly connected with clamp plate of right-hand member of second gasbag, two springs of clamp plate right flank through fore-and-aft symmetry are connected with the inside right flank elastic connection of housing, the left side of second gasbag all communicates there is the trachea, the trachea runs through to the housing left side, the connecting position of trachea and second gasbag all is equipped with the valve.

Further, the knob front-back symmetry fixedly connected with two push plates of two valves are corresponding to the frame plate up end, frame plate up end central point puts fixedly connected with extension board, two memory springs of symmetry fixedly connected with around the extension board left side, two through-holes have been seted up to the housing left surface corresponding to two memory springs, the fixed cover in protection layer lateral surface of housing left side cable is equipped with the lantern ring, two memory springs pass through-hole and lantern ring fixed connection respectively, two connecting rods and housing left surface fixed connection that the annular equidistance distributes are passed through on the lantern ring right side.

Compared with the prior art, the invention has the beneficial effects that:

1. this scheme is through setting up the support in order to make the gap between the conductor inside the outer shielding layer, sets up first gasbag between the support, can absorb the heat that the conductor sent through the gasbag to improve the radiating effect of conductor, and when the conductor temperature is too high and spontaneous combustion, first gasbag is heated the damage and sprays inert gas, helps putting out a fire.

2. This scheme sets up solid fixed ring and pillar between outer shielding layer and protective layer, and pillar central point puts outwards arches, and the pillar is ductile metal for when the cable is pressed, the pillar can take place deformation in order to reduce the pressure to the conductor, thereby improves the compressive capacity of conductor.

3. According to the scheme, the spring is arranged in the inserting cylinder, the first connector and the second connector are buckled together through the clamping jaw, when a cable catches fire, the memory spring is heated and retracted, so that the frame plate is driven to slide leftwards, the push rod is driven to push the clamping jaw, the clamping jaw is separated from the second connector, the second connector is sprung out under the action of the spring, the power supply is cut off, and the clamping jaw is separated from the ignition cable, so that the fire is prevented from spreading continuously.

4. The knob that can also drive push pedal touching two valves when this scheme frame plate slides to open two trachea, make the inert gas in the second gasbag spout towards the fire through the trachea, thereby put out a fire.

Drawings

FIG. 1 is a perspective front view of the overall structure of the present invention;

FIG. 2 is a perspective bottom view of the overall structure of the present invention;

FIG. 3 is a schematic illustration in semi-section of FIG. 1 of the present invention;

FIG. 4 is a schematic illustration in semi-section of FIG. 2 of the present invention;

FIG. 5 is an exploded view of the internal structure of the cable of the present invention;

FIG. 6 is a schematic view of the structure of the frame plate of the present invention;

FIG. 7 is a schematic illustration of a single cable construction of the present invention;

FIG. 8 is an enlarged schematic view of the invention at A in FIG. 4;

fig. 9 is an enlarged schematic view of the invention at B in fig. 5.

The reference numerals in the figures illustrate:

1. a conductor; 11. an insulating layer; 12. an inner shielding layer; 13. a bracket; 14. a first air bag; 15. a fixing ring; 16. an outer shielding layer; 17. a protective layer; 18. a support post; 2. a seal head; 21. a first terminal; 22. a second binding post; 23. a first joint; 24. a rod; 25. a second joint; 26. a plug cylinder; 27. a claw; 28. a hinge base; 3. a housing; 31. a through port; 32. a carrier plate; 33. a pressing plate; 34. a second air bag; 35. a valve; 36. an air pipe; 4. a frame plate; 41. a push rod; 42. a slide plate; 43. a chute; 44. a push plate; 45. a support plate; 46. a memory spring; 47. a collar.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention; it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments, and that all other embodiments obtained by persons of ordinary skill in the art without making creative efforts based on the embodiments in the present invention are within the protection scope of the present invention.

Example 1:

referring to fig. 1 to 9, an anticorona photovoltaic power cable comprises a cable body, wherein two groups of cable bodies are arranged, each group of cable body consists of four annular conductors 1 distributed at equal intervals, and the outer side of each conductor 1 is wrapped with an insulating layer 11; the corona resistant mechanism is arranged on the outer side of the conductor 1 and comprises an inner shielding layer 12 and an outer shielding layer 16, wherein the inner shielding layer 12 is respectively wrapped on the outer side of the insulating layer 11, the outer shielding layer 16 is wrapped on the outer side of the inner shielding layer 12, and the inner shielding layer 12 and the outer shielding layer 16 are formed by mixing and processing polyvinyl chloride and silicon oxide; the inside horizontal equidistance fixedly connected with a plurality of support 13 of outer shielding layer 16, the annular equidistance in support 13 outer edge position has seted up four round holes that can supply conductor 1 to pass, can make there be the space in order to improve the radiating effect between the conductor 1 through the setting of support 13, adjacent fixedly connected with first gasbag 14 between the support 13, the inert gas is filled in the first gasbag 14.

Through adopting above-mentioned technical scheme, through interlude the round hole at support 13 respectively with conductor 1 for there is the gap between the conductor 1, thereby reduce the friction between the conductor 1, and all be provided with first gasbag 14 between two adjacent supports 13, the inert gas of first gasbag 14 intussuseption is through compressing, when the conductor 1 takes place the spontaneous combustion because of the high temperature, can make first gasbag 14 heated breakage, thereby make inert gas jet out, and then put out a fire to the fire point, reduce the continuous possibility of spreading of fire, reduce economic loss and the harm of conflagration, the double protection of inner shielding layer 12 and outer shielding layer 16 and with inner shielding layer 12 and outer shielding layer 16 by polyvinyl chloride and silicon oxide mixed processing form, improve conductor 1 anticorona effect greatly.

As shown in fig. 5, 7 and 9, the outer side of the outer shielding layer 16 is horizontally and equidistantly fixedly connected with a plurality of fixing rings 15, a plurality of supporting columns 18 are fixedly connected between adjacent fixing rings 15 at equal intervals, the central positions of the supporting columns 18 arch outwards, the supporting columns 18 are made of ductile metal, the outer side surfaces of the fixing rings 15 are wrapped with protective layers 17, two groups of cable bodies are fixedly connected with sealing heads 2 at one ends, close to each other, of the protective layers 17, and one ends, close to the sealing heads 2, of the cable bodies are fixedly connected with the sealing heads 2.

Through adopting above-mentioned technical scheme, through setting up solid fixed ring 15 between outer shielding layer 16 and protective layer 17 can improve the intensity of cable, annular equidistance fixedly connected with a plurality of pillar 18 between two adjacent solid fixed rings 15, and the central point of pillar 18 puts outwards arches, and pillar 18 is ductile metal material, make pillar 18 can take place elastic deformation when the pressurized, thereby reduce the pressure to conductor 1, improve the compressive capacity of conductor 1, and then prolong the life-span of cable, and owing to gu the existence of solid fixed ring 15 can produce the cavity between protective layer 17 and the outer shielding layer 16, thereby have thermal-insulated effect, when protective layer 17 is pressed simultaneously, still take place the space of deformation, further improve the compressive effect of cable.

As shown in fig. 2, fig. 3, fig. 6, fig. 8 and fig. 9, the outer sides of the ends, close to each other, of the two groups of cable bodies are provided with a housing 3, the right ends of left conductors 1 inside the housing 3 are fixedly connected with first binding posts 21, the left ends of right conductors 1 inside the housing 3 are fixedly connected with second binding posts 22, the first binding posts 21 penetrate to the right side of the sealing head 2, the second binding posts 22 penetrate to the left side of the sealing head 2, the first binding posts 21 are matched with the second binding posts 22, a first joint 23 is fixedly connected with a fixed connecting sleeve on the outer side of the sealing head 2 on the left side inside the housing 3, four inserting rods 24 are fixedly connected with the outer side of the right side of the first joint 23 in an annular equidistant manner, the annular outer side of the sealing head 2 on the right side inside the housing 3 is fixedly connected with four inserting cylinders 26 capable of being inserted by the inserting rods 24 in an annular equidistant manner, one side, which is fixedly connected with springs on the inner side of the inserting cylinders 26 far from the inserting rods 24, and two annular hinging seats 28 are fixedly connected with two hinging seats 28 on the left side surface of the first joint 23 in an annular manner;

the jack catch 27 top sets up frame plate 4, the front and back symmetry fixedly connected with two push rods 41 of frame plate 4 lower extreme front and back, symmetrical fixedly connected with two carrier plates 32 on the inside wall around the housing 3 of frame plate 4 top, the lower terminal surface of carrier plate 32 is close to left side position and has been seted up the spout 43 that the cross-section is T shape structure, sliding connection has slide 42 rather than matching in spout 43, the lower extreme of slide 42 respectively with frame plate 4 up end fixed connection, carrier plate 32 up end is equipped with second gasbag 34 respectively, the common fixedly connected with clamp plate 33 of right-hand member of second gasbag 34, clamp plate 33 right flank is through two springs of front and back symmetry and housing 3 inside right flank elastic connection, the left side of second gasbag 34 all communicates with trachea 36, trachea 36 runs through to housing 3 left side, the hoops of trachea 36 and second gasbag 34 are all equipped with valve 35, the knob front and back symmetry fixedly connected with two push plates 44 of two valve 35 of frame plate 4 up end correspondence, frame plate 4 up end central point position is equipped with second gasbag 34 respectively, the right side face is equipped with two memory collar 46 respectively, the left side face of cover plate 45 is connected with two memory collar 46 through the left side face of housing 3, the left side face of cover plate 46 is connected with two memory collar 46, the left side face of cover plate 46 is fixed with the left side face of cover plate 46, the left side face of cover plate 46 is connected with the left side face of cover plate 46 through the left side face of the cover plate 46.

By adopting the technical scheme, the cable on the left side of the housing 3 is used as a power transmission line, the right end of the cable on the right side of the housing 3 is electrically connected with a power supply device, the second binding post 22 on the left end of the cable on the right side of the housing 3 is inserted into the first binding post 21 on the right side of the cable on the left side, at the moment, the four inserting rods 24 on the right side of the first connector 23 are respectively inserted into the inserting cylinders 26 on the right side of the second connector 25, the springs in the inserting cylinders 26 are compressed, then the second connector 25 and the first connector 23 are clamped together by stirring the clamping claws 27, one side of the clamping claws 27 close to the first connector 23 is elastically connected through the springs, so that the clamping claws 27 are kept fixed under the action of the springs, the connection of the two cables is completed, the lantern rings 47 on the left side cable are made of metal materials, and when the left side cable has spontaneous combustion due to overhigh temperature of the conductor 1, the lantern rings 47 can conduct heat to the two memory springs 46, the memory spring 46 is made of memory alloy, when the memory spring 46 is heated, one end of the memory spring close to the support plate 45 contracts towards one end close to the lantern ring 47, so that the frame plate 4 is pulled to slide leftwards along the lower end face of the carrier plate 32, the frame plate 4 is in sliding connection with the sliding groove 43 on the lower end face of the carrier plate 32 through the sliding plate 42, so that the frame plate 4 is ensured to always keep rectilinear motion, when the frame plate 4 moves leftwards, two push rods 41 on the lower end face of the frame plate 4 respectively touch the left deflector rods of the two clamping jaws 27, so that the clamping jaws 27 leave the second connector 25, at the moment, the second connector 25 loses limit, the spring in the socket 26 is rebounded, the left cable is fixedly connected with the housing 3, the right cable is in sliding connection with the housing 3, so that the right cable is ejected rightwards, the second binding post 22 leaves the first binding post 21, the left cable is powered off, the frame plate 4 has the functions of protecting electric equipment and power supply equipment, in the process of sliding leftwards, the push plate 44 on the frame plate 4 touches the knob on the valve 35 at the corresponding position, so that the valve 35 is opened, compressed inert gas is filled in the two second air bags 34, so that the inert gas is sprayed to a fire point through the air pipe 36, the fire is extinguished by the fire point, the inert gas in the first air bags 14 is matched, the extinguishing effect is greatly improved, the situation that the fire continuously spreads to cause a large-scale fire disaster is avoided, the two springs on the right side of the pressing plate 33 are in a compressed state when the valve 35 is not opened, after the valve 35 is opened, the springs rebound gradually, so that the pressing plate 33 is pushed to slide leftwards, the two second air bags 34 are extruded, the inert gas in the second air bags 34 can be sprayed to the fire point at a higher speed, the upper end face of the cover plate 3 is clamped with the cover plate, and various structures in the cover plate 3 can be protected, and false contact is prevented.

The using method comprises the following steps: through alternate conductor 1 respectively at the round hole of support 13 for there is the gap between the conductor 1, thereby reduce the friction between the conductor 1, when conductor 1 takes place the spontaneous combustion because of the high temperature, can make first gasbag 14 heated breakage, thereby make inert gas jet go out, and then put out a fire to the ignition point, through setting up the compressive strength of fixed ring 15 and the integrated configuration of pillar 18 between outer shielding layer 16 and protective layer 17, when the cable of left side takes place the spontaneous combustion because of conductor 1 high temperature, the lantern ring 47 can heat conduction to two memory springs 46, memory springs 46 are made by memory alloy, when memory springs 46 are heated, the one end that it is close to the lantern ring 47 can take place to shrink to the one end that is close to the lantern ring 47, thereby pull frame plate 4 along carrier plate 32 lower extreme face left slip, when frame plate 4 left motion, thereby make jack catch 27 leave second joint 25, the spring that the second joint 25 loses the spring in the cartridge 26 takes place to rebound, make right side cable be popped up to the right, make second plug 22 and make the second plug 22 draw out the corresponding gas of the side of plug plate 27, thereby make the inert gas of the side 35 stretch out a fire to the side of the protection device, and the gas of the side of the plug plate 4 is opened to the left side, and the air bag is opened to the corresponding to the one end of the high-phase gas, thereby the inert gas is blown out from the high pressure side 35, the fire device is blown out to the fire in the fire is continuously because of the air chamber 35, and the fire device is opened in the position is opened to the position to the fire-extinguishing device is greatly-friendly, and the fire device is opened, the fire-extinguishing device is opened to the fire-stop device is done.

The above description is only of the preferred embodiments of the present invention; the scope of the invention is not limited in this respect. Any person skilled in the art, within the technical scope of the present disclosure, may apply to the present invention, and the technical solution and the improvement thereof are all covered by the protection scope of the present invention.

Claims

1. An anticorona power cable for photovoltaic, characterized in that: comprising

The cable comprises a cable body, wherein two groups of cables are arranged, each group of cables consists of four annular conductors (1) which are distributed at equal intervals, and the outer side of each conductor (1) is wrapped with an insulating layer (11);

the corona resistant mechanism is arranged on the outer side of the conductor (1) and used for weakening the adverse effect of corona on the conductor (1), and comprises an inner shielding layer (12) and an outer shielding layer (16), wherein the inner shielding layer (12) is respectively wrapped on the outer side of the insulating layer (11), the outer shielding layer (16) is respectively wrapped on the outer side of the inner shielding layer (12), and the inner shielding layer (12) and the outer shielding layer (16) are formed by mixing and processing polyvinyl chloride and silicon oxide;

the inner part of the outer shielding layer (16) is horizontally and equidistantly fixedly connected with a plurality of brackets (13), four round holes through which the conductors (1) can pass are annularly and equidistantly formed in the outer edge positions of the brackets (13), and gaps are formed between the conductors (1) through the arrangement of the brackets (13) so as to improve the heat dissipation effect;

a first air bag (14) is fixedly connected between the adjacent brackets (13), and inert gas is filled in the first air bag (14);

the outer side of the outer shielding layer (16) is horizontally and equidistantly fixedly connected with a plurality of fixing rings (15), a plurality of supporting columns (18) are annularly and equidistantly fixedly connected between the adjacent fixing rings (15), the central positions of the supporting columns (18) arch outwards, and the supporting columns (18) are made of ductile metal materials;

the outer side surface of the fixing ring (15) is wrapped with a protection layer (17), two groups of cables are fixedly connected with the sealing head (2) at one ends close to each other, and one end, close to the sealing head (2), of the protection layer (17) is fixedly connected with the sealing head (2).

2. The anticorona photovoltaic power cable of claim 1, wherein: two sets of the outside of the one end that the cable is close to each other is equipped with housing (3), the equal fixedly connected with first terminal (21) of right-hand member of the inside left side conductor (1) of housing (3), the equal fixedly connected with second terminal (22) of left end of the inside right side conductor (1) of housing (3), first terminal (21) run through to head (2) right side, second terminal (22) run through to head (2) left side, first terminal (21) cooperatees with second terminal (22).

3. The anticorona photovoltaic power cable of claim 2, wherein: the utility model discloses a novel socket, including casing (3) inside left side head (2) outside fixed connection cover is equipped with first joint (23), the right flank of first joint (23) is outer along the annular equidistance fixedly connected with four inserted bars (24) of position, the annular lateral surface fixed cover of head (2) on the inside right side of casing (3) is equipped with second joint (25), the right side is outer along the annular equidistance fixedly connected with of position four can supply inserted bar (24) male cartridge (26), and one side fixed connection spring of inserted cartridge (26) inside raw materials inserted bar (24).

4. A corona resistant photovoltaic power cable according to claim 3, wherein: the left side annular equidistant fixedly connected with two articulated seat (28) of first joint (23), articulated claw (27) are gone up respectively on articulated seat (28).

5. The anticorona photovoltaic power cable of claim 4, wherein: the utility model discloses a rack plate, including jack catch (27) and rack plate, set up frame plate (4) above jack catch (27), symmetrical fixedly connected with two push rods (41) around the lower extreme face of frame plate (4), symmetrical fixedly connected with two carrier plates (32) on the inside wall around housing (3) of frame plate (4) top, spout (43) that the cross-section is T shape structure have been seted up near left side position to terminal surface under carrier plate (32), sliding connection has slide (42) rather than the matching in spout (43), the lower extreme of slide (42) respectively with frame plate (4) up end fixed connection.

6. The anticorona photovoltaic power cable of claim 5, wherein: the support plate (32) up end is equipped with second gasbag (34) respectively, the common fixedly connected with clamp plate (33) of right-hand member of second gasbag (34), two springs of clamp plate (33) right flank through fore-and-aft symmetry and inside right flank elastic connection of housing (3), the left side of second gasbag (34) all communicates has trachea (36), trachea (36) run through to housing (3) left side, the hookup location of trachea (36) and second gasbag (34) all is equipped with valve (35).

7. The anticorona photovoltaic power cable of claim 6, wherein: the utility model discloses a novel electric power tool is characterized in that two push plates (44) are symmetrically connected with around the knob that frame plate (4) up end corresponds two valves (35), frame plate (4) up end central point puts fixedly connected with extension board (45), symmetry is connected with two memory springs (46) around extension board (45) left surface, two opening (31) have been seted up to cover shell (3) left surface corresponding two memory springs (46), cover (17) lateral surface fixed cover of cover shell (3) left side cable is equipped with lantern ring (47), two memory springs (46) pass opening (31) and lantern ring (47) fixed connection respectively, two connecting rods that annular equidistance was distributed are passed on lantern ring (47) right side and cover shell (3) left surface fixed connection.