CN114454455A

CN114454455A - Cable three-layer supply forming equipment

Info

Publication number: CN114454455A
Application number: CN202210134469.9A
Authority: CN
Inventors: 刘青云; 徐见道
Original assignee: Jiangxi Huacable Technology Co ltd
Current assignee: Jiangxi Huacable Technology Co ltd
Priority date: 2022-02-14
Filing date: 2022-02-14
Publication date: 2022-05-10

Abstract

The invention discloses a cable three-layer supply forming device, which comprises an extruder and a die head, wherein the extruder comprises a shell and a threaded sleeve arranged in the shell, one end of the threaded sleeve extends out of the shell to form an extrusion port, the interior of the threaded sleeve is hollowed to form an inner cavity, a feeding box for adding materials into the inner cavity is arranged on the shell, a step-by-step temperature control device can control the temperature of an extrusion screw rod step by step, the extrusion temperature of raw materials at each stage can be accurately controlled, and further the extrusion speed can be accelerated, because the friction heat and the shearing heat generated by the high-speed operation of the extruder can destroy the heat balance, the temperature can be difficultly reduced by the step-by-step temperature control device, a cooling circulation device arranged in a cooling tank can strengthen the cooling strength and improve the adjustability of the temperature of the raw materials, the raw materials enter a forming cavity from an intermediate layer discharge port and an inner layer feed port to wrap wires, and a guide chute guides the outer layer raw materials into an extrusion gap to wrap the raw materials at the inner layer and the intermediate layer, the three layers of raw materials are integrally formed on the lead, so that the production efficiency is improved.

Description

Cable three-layer supply forming equipment

Technical Field

The invention relates to the field of cable three-layer supply forming equipment.

Background

The cable includes power cable, control cable, compensation cable, shielding cable, high-temperature cable, computer cable, signal cable, coaxial cable, fire-resistant cable, marine cable, mining cable, aluminum alloy cable and the like. They are composed of single or multi-strand wires and insulating layers, and are used for connecting circuits, electric appliances and the like. At present, because some cables are in a severe environment, the requirements on the service life and quality of the cables are high, and the production of the cable with three-layer protection effect is a need of social development.

Three-layer supply equipment in the prior art has low production efficiency and can not meet the requirements of customers, the control of the temperature of each stage is very critical in the process from the melting of raw materials in an extruder to the extrusion, the extrusion speed is directly influenced, the temperature is too high, the flowability of the raw materials is high, the later-stage forming is unstable, the temperature is too low, and the extrusion speed is slow; the die head in the prior art can not be integrally formed for the cables supplied by three layers, so that the production efficiency is low, and the extrusion is uneven.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the cable three-layer supply forming equipment with high forming speed

In order to achieve the above purpose, the invention provides the following technical scheme: a cable three-layer supply forming device comprises an extruder and a die head, wherein the extruder comprises a shell and a threaded sleeve arranged in the shell, one end of the threaded sleeve extends out of the shell to form an extrusion opening, the interior of the threaded sleeve is hollowed to form an inner cavity, a feeding box for feeding materials into the inner cavity is arranged on the shell, an extrusion screw rod for extruding the materials to the extrusion opening is arranged in the inner cavity, and one end, far away from the extrusion opening, of the extrusion screw rod is connected with a transmission motor for driving the extrusion screw rod to rotate; the die head comprises a shell, a conical through hole for a lead to pass through is formed in the shell, the hole diameter of the lead penetrating end is larger than that of the lead penetrating end, a middle-layer feed port and an inner-layer feed port are formed in the side wall of the shell, a middle-layer die and an inner-layer die are sequentially arranged in the shell, the middle-layer feed port and the inner-layer feed port are correspondingly communicated with a middle-layer discharge port and an inner-layer discharge port, the number of the extruders is three, a stepped temperature control device is mounted on a screw sleeve of the extruder, a cooling groove is formed by hollowing out an extrusion screw, and a cooling circulation device is mounted in the cooling groove; the outer shell lead penetrating end is connected with an outer die head through a gland, a through hole structure is arranged in the outer die head, the through hole structure extends and shrinks to the middle part towards one end away from the gland to form a conical inner cavity, a port of the conical inner cavity away from the gland and the inner wall of the through hole of the outer die head form an annular interface, an outer die is sleeved in the outer die head away from the gland, an extrusion gap is reserved between the port of the outer die close to the gland and the annular interface, an outer layer feed inlet is arranged on the outer die head and correspondingly communicated with a guide chute extending to the extrusion gap on the outer wall of the outer die, an inner die sleeve with a conical through hole is sleeved in the outer die head, the conical inner cavity of the outer die head and the conical through hole of the inner die sleeve form a conical forming cavity, the outer layer discharge outlet, a middle layer discharge outlet and an inner layer discharge outlet are communicated with the forming cavity, and the extrusion ports of the three extruders are respectively correspondingly connected with the inner layer feed inlet through connectors, A middle layer feeding hole and an outer layer feeding hole.

Adopt above-mentioned technical scheme, substep temperature regulating device can carry out substep accuse temperature to extruding the screw rod, the accurate every stage raw materials extrusion temperature of accuse, and then can accelerate extrusion speed, because frictional heat and the shearing heat that the extruder produced when high-speed operation can destroy heat balance, substep temperature regulating device can be difficult to the temperature drop sometimes, the cooling cycle device of installing in the cooling bath can strengthen the cooling dynamics, the improvement is to the controllability of raw materials temperature, the raw materials gets into the shaping chamber and wraps up the wire from intermediate layer discharge gate and inlayer feed inlet, the baffle box wraps up the leading-in extrusion clearance of outer raw materials inlayer and middle-level raw materials, make three-layer raw materials integrated into one piece on the wire, and the production efficiency is improved.

The inner layer die and the middle layer die are in a conical shape, spiral grooves are formed in the outer walls, close to the wire penetrating end, of the inner layer die and the middle layer die, spiral grooves are formed in the outer conical surface of the middle layer die and the outer layer die, the spiral grooves take the middle layer feed inlet and the outer layer feed inlet as starting points, the outer walls of the corresponding middle layer die and the outer layer die are wound and arranged, the middle layer die and the inner layer die extend to the wire penetrating end and extend to the middle layer discharge outlet and the inner layer discharge outlet, a plurality of spiral grooves can be arranged corresponding to the communication ports with the middle layer discharge outlet and the inner layer discharge outlet, a wire channel is formed in the central shaft of the inner layer die, the wire channel is connected with an inner die head close to the wire penetrating end, the wire penetrating end of the inner die head is conical, and a through hole is formed in the center of the wire penetrating end to allow a wire to penetrate out.

By adopting the technical scheme, the middle layer die and the inner layer die are conical, and the spiral grooves formed in the outer conical surface can uniformly extrude raw materials to the inner layer discharge hole and the middle layer discharge hole and then enter the forming cavity. The inner die head can guide and restrain the raw material forming effect on the conducting wire.

Further, a regulator for controlling the temperature in the die head is arranged on the die head.

By adopting the technical scheme, the temperature regulator arranged on the die head can control the temperature of the raw material in the die head, so that the temperature of the raw material during the package forming is ensured, the raw material cannot be extruded due to cooling and solidification after the die is stopped, and the raw material in the die head can be melted by the temperature regulator before the die is started.

And a plurality of connectors are arranged on the guide chute and the connector communicated with the extrusion gap.

By adopting the technical scheme, the whole extrusion gap can be uniformly filled with the raw materials, and the uniform molding of the cable is facilitated.

The step-by-step temperature control device comprises a plurality of heating coils which are arranged on a screw sleeve at intervals, the screw sleeve is divided into a plurality of heating zones by the corresponding heating coils, a condensing sleeve for cooling the temperature of the screw sleeve is arranged on the screw sleeve corresponding to each heating zone, the condensing sleeve on each heating zone is connected with a circulating cooling water tank for circularly cooling water in the condensing sleeve, a temperature sensor is connected to the screw sleeve of each heating zone, and the temperature sensor is connected with a console capable of displaying temperature.

Adopt above-mentioned technical scheme, the heating coil heats in the zone of heating that corresponds respectively, and the control of cooling down is carried out in the zone of heating that corresponds to the condensing jacket simultaneously, and the temperature on the temperature-sensing ware response swivel nut transmits the control cabinet, conveniently observes the temperature in every zone of heating.

The water circulation cooling device is characterized in that a circulation water tank is further arranged, the condensation sleeve is internally provided with a circulation water tank wound around the screw sleeve, the circulation water tank is provided with a water outlet and a water inlet, the water inlet of each circulation water tank is communicated through a water inlet pipe, the water outlet of each circulation water tank is communicated through a water outlet pipe, the water inlet pipe and the water outlet pipe are connected with a circulation cooling water tank to carry out circulation cooling on water in each circulation water tank, and the electromagnetic valve for controlling the flow rate of water flow is arranged at each water inlet corresponding to the water inlet pipe.

By adopting the technical scheme, according to the temperature on the observation console, the flow velocity of water flow in the corresponding circulating water tank can be controlled through the electromagnetic valve, so that the temperature of each heating area can be accurately controlled.

Further setting, the cooling circulation device includes two cooling tubes that are parallel to each other, and this cooling tube one end is for intercommunication embedding each other in the cooling bath, two the cooling tube other end is connected with recirculated cooling water tank and carries out circulative cooling to the water in the circulating line, first bearing is installed to the cooling bath bottom, and the second bearing is installed to the other end, two cooling tubes keep motionless when first bearing and second bearing cup joint the both ends messenger of two cooling tubes respectively and extrude the screw rod rotation.

Adopt above-mentioned technical scheme, the recirculated cooling water tank carries water to circulate to the cooling tube from the second inlet tube, to extruding the inside temperature of screw rod and control of cooling down, owing to extrude the screw rod and can rotate, the bearing at cooling tube both ends can not influence and can also guarantee under the rotatory circumstances of extrusion screw rod that the cooling tube does not rotate, and this simple structure is effective.

The upper side, the lower side, the left side and the right side of the gland are respectively provided with an adjusting bolt, an adjusting gap is formed between the outer wall of the outer die head and the inner wall of the gland, and the adjusting bolts can adjust the relative position of the outer die head and the inner die head.

By adopting the technical scheme, the position of the inner die head in the forming cavity can be properly adjusted, and the wire is prevented from being eccentric.

The inner layer feed inlet and the middle layer feed inlet are positioned on the same side of the shell, and the outer layer feed inlet is arranged at the top of the outer die head and is provided with an upward opening.

By adopting the technical scheme, the extruder is convenient to connect with an extruder.

Further, an adjusting rack for lifting and rotating the die head is connected below the die head.

By adopting the technical scheme, the height and the direction of the die head can be adjusted, and the connection between the die head and the extruder is facilitated.

In summary, the invention has the following beneficial effects: to the raw materials substep accuse temperature in the screw shell, utilize the solenoid valve to adjust the velocity of water flow in the circulating water tank to control cooling temperature that can be accurate, and then accelerate extrusion speed, the internal structure design of mould aircraft nose makes the cable integrated into one piece that the three-layer was supplied with, this extruder and the great promotion of combining of mould aircraft nose the production efficiency etc. of cable.

Drawings

FIG. 1 is a schematic perspective view of the present invention;

FIG. 2 is a cross-sectional view of an extruder of the present invention;

FIG. 3 is an enlarged view of FIG. 2A;

FIG. 4 is an enlarged view of FIG. 2B;

FIG. 5 is an exploded view of the die head of the present invention;

fig. 6 is a cross-sectional view of a die head of the present invention.

The reference numbers in the figures illustrate:

1. an extruder; 11. a housing; 12. a threaded sleeve; 13. extruding a screw; 131. a first bearing; 132. a second bearing; 14. a circulating cooling water tank; 15. a cooling circulation device; 16. a feed box; 17. a cooling tank; 18. a drive motor; 151. a cooling tube; 2. a die head; 20. a helical groove; 21. a frame; 22. a housing; 23. a middle layer mold; 231. a middle layer feed inlet; 232. a middle layer discharge hole; 24. an inner layer mold; 241. an inner layer feed inlet; 242. an inner layer discharge hole; 25. an outer die head; 251. an outer layer feeding hole; 26. a gland; 261. adjusting the bolt; 27. an outer layer mold; 271. a material guide chute; 28. an inner die head; 29. an inner die sleeve; 3. a connector; 4. a console; 5. a step-by-step temperature control device; 51. a condensing sleeve; 511. a circulating water tank; 52. a temperature sensor; 53. heating a ring; 54. a water inlet pipe; 55. a water outlet pipe; 541. a water inlet; 551. a water outlet; 56. an electromagnetic valve; 6. a molding cavity; 7. a regulator;

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In order to clearly explain the technical features of the present invention, the following detailed description of the present invention is provided with reference to the accompanying drawings.

As shown in fig. 1-6, a cable three-layer supply molding device comprises an extruder 1 and a die head 2, wherein the extruder 1 comprises a housing 11 and a threaded sleeve 12 installed in the housing 11, one end of the threaded sleeve 12 extends out of the housing 11 to form an extrusion opening, the interior of the threaded sleeve 12 is hollowed to form an inner cavity, a feeding box 16 for feeding a material into the inner cavity is installed on the housing 11, an extrusion screw 13 for extruding the material to the extrusion opening is installed in the inner cavity, and one end of the extrusion screw 13, which is far away from the extrusion opening, is connected with a transmission motor 18 for driving the extrusion screw 13 to rotate; the die head 2 comprises a shell 22, a conical through hole for a lead to pass through is arranged in the shell 22, the aperture of the lead penetrating end is larger than that of the lead penetrating end, a middle layer feed inlet 231 and an inner layer feed inlet 241 are formed in the side wall of the shell 22, a middle layer die 23 and an inner layer die 24 are sequentially arranged in the shell 22, and the middle layer feed inlet 231 and the inner layer feed inlet 241 are correspondingly communicated with a middle layer discharge outlet 232 and an inner layer discharge outlet 242; referring to fig. 1 and 2, three extruders 1 are provided, a stepped temperature control device 5 is installed on a screw sleeve 12 of the extruder 1, a cooling tank 17 is formed by hollowing out an extrusion screw 13, and a cooling circulation device 15 is installed in the cooling tank 17; the raw materials pass through the charging box 16 and get into the inner chamber of swivel nut 12 and melt step by step, and every stage all has a gradual temperature change process in proper order, has accurate accuse to the temperature, can satisfy the requirement of extruding mouthful raw materials temperature, can improve the extrusion speed of raw materials again. Referring to fig. 5 and 6, the lead-through end of the outer shell 22 is connected to the outer die head 25 through the pressing cover 26, the outer die head 25 is a through-hole structure and extends and shrinks to the middle part towards the end far from the pressing cover 26 to form a conical inner cavity, the conical inner cavity is favorable for wrapping and forming raw materials, the port of the conical inner cavity far from the pressing cover 26 and the inner wall of the through-hole of the outer die head 25 form an annular interface, the end of the outer die head 25 far from the pressing cover 26 is internally sleeved with an outer layer die 27, an extrusion gap is left between the port of the outer layer die 27 close to the pressing cover 26 and the annular interface, the outer die head 25 is provided with a material guide groove 271 communicated with the outer wall of the outer layer die 27 and extending to the extrusion gap correspondingly, the inner die sleeve 29 with a conical through hole therein is sleeved in the outer layer die 27, the conical inner die cavity of the outer die head 25 and the conical through hole of the inner die sleeve 29 form a conical forming cavity, and the outer layer discharge hole, the middle layer discharge hole 232 and the inner layer discharge hole 242 are communicated with the forming cavity, extrusion ports of the three extruders 1 are correspondingly connected with an inner layer feed port 241, a middle layer feed port 231 and an outer layer feed port 251 through connectors 3. In the extrusion molding process, two extruders 1 respectively introduce raw materials from an inner layer feed port 241 and a middle layer feed port 231 into a molding inner cavity 6 to wrap the wires, and the other extruder 1 is fully extruded into an extrusion gap from an outer layer feed port 251 through a guide chute 271. This equipment can be according to the production requirement in the production process, through closing outer extruder 1, can realize two-layer cable production in the interior, and through closing outer, middle layer extruder 1 can realize the production of individual layer cable, and every layer of cable shaping in mould aircraft nose 2 does not influence each other.

Referring to fig. 5-6, the outer walls of the inner layer mold 24 and the middle layer mold 23 near the wire leading-out end are recessed to form an inner layer discharge port 242 and a middle layer discharge port 232, two annular discharge ports can be formed between the recessed inner layer discharge port 242 and the middle layer discharge port 232 and the inner wall of the shell 22, and the guiding is wrapped by the annular raw material forming. The middle layer die 23 and the inner layer die 24 are in a conical shape, the outer conical surfaces are provided with spiral grooves 20, the spiral grooves 20 use the middle layer feed port 231 and the outer layer feed port 251 as starting points, the outer walls of the corresponding middle layer die 23 and the outer layer die 27 are wound and arranged, and extend to the middle layer discharge port 232 and the inner layer discharge port 242 towards the lead penetrating end, and a plurality of communication ports corresponding to the middle layer discharge port 232 and the inner layer discharge port 242 of the spiral grooves 20 can be arranged. In the process that the raw materials are extruded to the discharge port, the raw materials enter the discharge port through the plurality of communicating ports, so that the discharge port is uniformly filled to form a ring shape. A lead passage is arranged on the central shaft of the inner layer die 24, the lead passage is connected with an inner die head 28 near the lead penetrating end, the lead penetrating end of the inner die head 28 is conical, a through hole is arranged in the center for the lead to penetrate through, and the outer layer discharge hole, the middle layer discharge hole 232 and the inner layer discharge hole 242 are communicated with the forming cavity. The wire passageway communicates interior die head 28 and supplies the conductor to wear out, and interior middle level raw materials are wrapped up the wire on the interior die head 28 through the extrusion constraint of toper shaping inner chamber 6 from the discharge gate for the raw materials shaping is more even.

The die head 2 is provided with an adjuster 7 for controlling the temperature in the die head 2. This regulator 7 can be for in mould aircraft nose 2 or plus install the heating plate, and the heating plate passes through 7 controlled temperature of regulator and heats 2 inside of mould aircraft nose, and extrusion equipment shuts down the back, and remaining raw materials can the cooling solidification in the mould aircraft nose 2, when restarting, need heat remaining raw materials and melt, ensure that equipment normally works.

The material guide groove 271 is provided with a plurality of connectors communicated with the extrusion gap, and as the connectors communicated with the material outlet are arranged on the spiral groove 20, the whole extrusion gap can be uniformly filled with the raw materials, which is beneficial to uniform molding of cables.

Adjusting bolts 261 are respectively arranged on the upper side, the lower side, the left side and the right side of the gland 26, an adjusting gap is formed between the outer wall of the outer die head 25 and the inner wall of the gland 26, and the relative positions of the outer die head 25 and the inner die head 28 are properly adjusted through the four adjusting bolts 261, so that the wire outlet end of the inner die head 28 and the wire outlet end of the outer die head 25 are kept on the same horizontal line, and the normal wire outlet of a cable is ensured.

The inner layer feed inlet 241 and the middle layer feed inlet 231 are located on the same side of the shell 22, connection of the inner layer extruder 1 and the middle layer extruder 1 is facilitated, the outer layer feed inlet 251 is arranged at the top of the outer die head 25, an opening of the outer layer feed inlet faces upwards, and the outer layer extruder 1 is connected, and therefore space is reasonably utilized.

In the process of butting the extrusion port of the extruder 1 to the die head 2, the extruder 1 is heavy relative to the die head 2 and is not easy to move and adjust, and in order to facilitate the connection between the extruder 1 and the die head 2, an adjusting rack 21 for lifting and rotating the die head 2 is connected below the die head 2. The lifting device can adopt an air cylinder, a hydraulic cylinder or a hand-operated lifting rod, and universal wheels with a braking function can be arranged under the frame 21.

Referring to fig. 2-4, the stepped temperature control device 5 includes a plurality of heating coils 53 arranged at intervals on the screw sleeve 12, the screw sleeve 12 is divided into a plurality of heating zones by the corresponding heating coils 53, a condensing sleeve 51 for cooling the temperature of the screw sleeve 12 is installed on the screw sleeve 12 corresponding to each heating zone, the condensing sleeve 51 on each heating zone is connected with a circulating cooling water tank 14 for circulating and cooling water in the condensing sleeve 51, a temperature sensor 52 is connected to the screw sleeve 12 of each heating zone, and the temperature sensor 52 is connected with a console 4 capable of displaying the temperature. The frictional heat and the shearing heat generated by the extrusion screw 13 during high-speed operation can destroy the heat balance, the temperature exceeds the process temperature, so that the temperature needs to be effectively controlled, the temperature sensor 52 senses the temperature on the screw sleeve 12 at each stage and displays the temperature on the control console 4, the temperature of each heating zone is convenient to observe, when the temperature exceeds the process temperature, the circulating cooling water tank 14 can be started to cool and circulate the water in the condensing sleeve 51, the temperature of the screw sleeve 12 at each heating zone is further reduced, and the temperature control effect is improved.

The condensing sleeve 51 is internally provided with circulating water tanks 511 which are wound around the threaded sleeve 12, the circulating water tanks 511 are provided with water outlets 551 and water inlets 541, the water inlets 541 of the circulating water tanks 511 are communicated through water inlet pipes 54, the water outlets 551 of the circulating water tanks 511 are communicated through water outlet pipes 55, the water inlet pipes 54 and the water outlet pipes 55 are connected with a circulating cooling water tank 14 to circularly cool the water in the circulating water tanks 511, and the electromagnetic valves 56 for controlling the flow rate of water flow are installed at the positions of the water inlets 541 corresponding to the water inlet pipes 54. The water after the inlet tube 54 will lower the temperature through recirculated cooling water tank 14 carries to every water inlet 541, certain heat on the swivel nut 12 is absorbed through the flow in recirculated water tank 511 to water, flow to outlet pipe 55 from delivery port 551 again and let in recirculated cooling water tank 14 and carry out cooling cycle, the basin that the winding set up can increase under certain area with the contact surface of swivel nut 12, improve cooling temperature control effect, the temperature requirement of every section zone of heating is different, through observing the data on the control cabinet 4, can audio-visually know the concrete temperature of every section zone of heating, when the temperature surpassed the technology temperature, can control the rivers velocity of flow of every section zone of heating inner loop water tank 511 through solenoid valve 56, thereby the temperature on the swivel nut 12 on every section of heating of accurate control zone of heating.

The cooling circulation device 15 comprises two cooling pipes 151 arranged in parallel, one ends of the cooling pipes 151 are communicated with each other and embedded in the cooling tank 17, and the other ends of the two cooling pipes 151 are connected with a circulating cooling water tank 14 to circularly cool water in the circulating pipes. Since the extrusion screw 13 rotates, in order to ensure that the condensation sleeve 51 remains stationary in the extrusion screw 13, the first bearing 131 is installed at the bottom of the cooling tank 17, the second bearing 132 is installed at the other end of the cooling tank, the first bearing 131 and the second bearing 132 are respectively sleeved at the two ends of the two cooling pipes 151, when the extrusion screw 13 rotates, the outer rings of the first bearing 131 and the second bearing 132 continuously rotate, and the inner rings and the cooling pipes 151 do not rotate. To further enhance the control of the temperature within the extrusion screw 13, a solenoid valve 56 for controlling the flow rate of water may be installed on a water pipe entering the cooling pipe 151.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the technical scope of the present invention, so that any minor modifications, equivalent changes and modifications made to the above embodiment according to the technical spirit of the present invention are within the technical scope of the present invention.

Claims

1. A cable three-layer supply forming device comprises an extruder (1) and a die head (2), wherein the extruder (1) comprises a shell (11) and a threaded sleeve (12) arranged in the shell (11), one end of the threaded sleeve (12) extends out of the shell (11) to form an extrusion opening, the interior of the threaded sleeve (12) is hollowed to form an inner cavity, a feeding box (16) for adding a material into the inner cavity is arranged on the shell (11), an extrusion screw (13) for extruding the material to the extrusion opening is arranged in the inner cavity, and one end, far away from the extrusion opening, of the extrusion screw (13) is connected with a transmission motor (18) for driving the extrusion screw (13) to rotate; mould aircraft nose (2) include shell (22), be equipped with the toper through-hole that supplies the wire to pass in shell (22), and the wire penetrates the end aperture and is greater than the wire and wears out the end aperture, shell (22) lateral wall is opened there are middle level feed inlet (231) and inlayer feed inlet (241), shell (22) inside is equipped with middle level mould (23) and inlayer mould (24) in proper order, and middle level feed inlet (231) and inlayer feed inlet (241) correspond intercommunication middle level discharge gate (232) and inlayer discharge gate (242), its characterized in that: the extruder (1) is provided with three extruders, a stepped temperature control device (5) is installed on a screw sleeve (12) of the extruder (1), the extrusion screw (13) is hollowed out to form a cooling tank (17), and a cooling circulation device (15) is installed in the cooling tank (17); the lead penetrating end of the shell (22) is connected with an outer die head (25) through a gland (26), the inner part of the outer die head (25) is of a through hole structure, one end far away from the gland (26) extends and reduces to the middle part to form a conical inner cavity, a port of the conical inner cavity far away from the gland (26) and the inner wall of the through hole of the outer die head (25) form an annular interface, an outer layer die (27) is sleeved in the end of the outer die head (25) far away from the gland (26), an extrusion gap is reserved between the port of the outer layer die (27) close to the gland (26) and the annular interface, an outer layer feed inlet (251) is arranged on the outer die head (25), a guide chute (271) correspondingly communicated with the outer wall of the outer layer die (27) and extending to the extrusion gap is sleeved in the outer layer die (27), an inner die sleeve (29) with a conical through hole formed in the inner die sleeve (271), and the conical inner cavity of the outer die head (25) and the conical through hole of the inner die sleeve (29) form a conical forming cavity (6), outer layer discharge gate, middle level discharge gate (232) and inlayer discharge gate (242) with become die cavity (6) intercommunication, three the extrusion mouth of extruder (1) corresponds respectively through connector (3) and connects inlayer feed inlet (241), middle level feed inlet (231) and outer feed inlet (251).

2. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: the outer walls of the inner layer die (24) and the middle layer die (23) close to the lead penetrating end are sunken inwards to form an inner layer discharge hole (242) and a middle layer discharge hole (232), the middle layer die (23) and the inner layer die (24) are in a conical shape, spiral grooves (20) are arranged on the outer conical surfaces, and the spiral groove (20) takes a middle layer feed inlet (231) and an outer layer feed inlet (251) as starting points, the outer walls of the corresponding middle layer die (23) and the outer layer die (27) are wound and arranged and extend to the middle layer discharge port (232) and the inner layer discharge port (242) towards the lead threading end, a plurality of communicating ports of the spiral groove (20) corresponding to the middle layer discharge port (232) and the inner layer discharge port (242) can be arranged, a lead channel is arranged on the central shaft of the inner layer die (24), an inner die head (28) is connected to the lead channel close to the lead penetrating end, the lead penetrating end of the inner die head (28) is conical, and a through hole is formed in the center of the inner die head for the lead to penetrate through.

3. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: and the die head (2) is provided with a regulator (7) for controlling the temperature in the die head (2).

4. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: the material guide groove (271) is provided with a plurality of interfaces communicated with the extrusion gap.

5. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: the step-by-step temperature control device (5) comprises a plurality of heating coils (53) which are arranged on a screw sleeve (12) at intervals, the screw sleeve (12) is divided into a plurality of heating zones by the corresponding heating coils (53), a condensing sleeve (51) for cooling the temperature of the screw sleeve (12) is arranged on the screw sleeve (12) corresponding to each heating zone, the condensing sleeve (51) on each heating zone is connected with a circulating cooling water tank (14) for circularly cooling water in the condensing sleeve (51), a temperature sensor (52) is connected on the screw sleeve (12) of each heating zone, and the temperature sensor (52) is connected with a console (4) capable of displaying the temperature.

6. A cable three-layer feed forming apparatus as claimed in claim 5, wherein: the condensing sleeve (51) is internally provided with a circulating water tank (511) which is wound around the threaded sleeve (12), the circulating water tank (511) is provided with a water outlet (551) and a water inlet (541), the water inlet (541) of each circulating water tank (511) is communicated through a water inlet pipe (54), the water outlet (551) of each circulating water tank (511) is communicated through a water outlet pipe (55), the water inlet pipe (54) and the water outlet pipe (55) are connected with a circulating cooling water tank (14) to circularly cool water in each circulating water tank (511), and the position of each water inlet (541) corresponding to the water inlet pipe (54) is provided with an electromagnetic valve (56) for controlling the flow rate of water flow.

7. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: cooling circulation device (15) include two cooling tube (151) that are parallel to each other, and this cooling tube (151) one end is for intercommunication each other imbed in cooling bath (17), two cooling tube (151) other end is connected with circulative cooling water tank (14) and carries out circulative cooling to the water in the circulating tube, first bearing (131) are installed to cooling bath (17) bottom, and second bearing (132) are installed to the other end, two cooling tube (151) keep motionless when first bearing (131) and second bearing (132) cup joint respectively the both ends messenger of two cooling tube (151) extrude screw rod (13) rotation.

8. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: adjusting bolts (261) are respectively arranged on the upper side, the lower side, the left side and the right side of the gland (26), an adjusting gap is formed between the outer wall of the outer die head (25) and the inner wall of the gland (26), and the relative position of the outer die head (25) and the inner die head (28) can be adjusted through the adjusting bolts (261).

9. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: the inner layer feed inlet (241) and the middle layer feed inlet (231) are located on the same side of the shell (22), and the outer layer feed inlet (251) is arranged at the top of the outer die head (25) and is upward in opening.

10. A cable three-layer feed forming apparatus as claimed in claim 1, wherein: an adjusting rack (21) for lifting and rotating the die head (2) is connected below the die head (2).