Optical cable extrusion die

Abstract

The present application relates to the technical field of extrusion die, specifically to a kind of optical cable extrusion die, comprising: fixed die and its inside flat section cavity and neck cavity, the fixed die is equipped with die head, the die head is designed with shunt cavity inside, and the shunt cavity and the narrow mouth of neck section are smoothly transitioned and docked, and the shunt cavity and neck section form die cavity between;The flat section cavity and neck cavity are installed with die core, the die core has a pen cavity inside, the die core has piston body and conical die core body, and spiral flow guide groove is opened on the conical die core body along the taper surface;Flat section cavity and neck cavity are also fixedly installed with wire feeding body, the wire feeding body is located in the die core, and both are coaxial design, wire feeding body axis is penetrated with wire channel;The present application realizes circumferential uniform pressure and flow under side feeding, outlet field is consistent, exempt from disassembly cleaning and rapid change, significantly improves forming stability and appearance quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of extrusion dies, in particular to a cable extrusion die. BACKGROUND

[0002] The extrusion die is installed at the end of an extruder, used to coat the outer surface of the cable core (loose sleeve core, tight sleeve fiber or cabling core) with a ring-shaped flow channel with molten plastic (such as PBT, PA, PVC, PE, LSZH, etc.), and complete the thickness and surface shaping through the die stand.

[0003] In the prior art, in the necking section before the ring-shaped flow channel, the molten material is most likely to remain on the cavity wall of the necking section during the process of being extruded to the ring-shaped flow channel, forming a dead zone, and although the extrusion die is easy to disassemble and clean, disassembly will cause many calibration problems. SUMMARY

[0004] The present application provides a cable extrusion die, which realizes circumferential pressure equalization, outlet field consistency, disassembly-free cleaning and rapid remodeling under side feeding through spiral flow guide, coaxial adjustable core, combined die cavity and in-situ cleaning, significantly improving forming stability and appearance quality.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0006] A cable extrusion die, comprising:

[0007] A fixed die and its internal flat section cavity and necking cavity, the fixed die is equipped with a die, the die is designed with a shunt cavity inside, and the shunt cavity and the narrow mouth of the necking section are smoothly connected and docked, and the shunt cavity and the necking section form a die cavity; a die core is installed in the flat section cavity and the necking cavity, the die core has a pen cavity inside, the die core has a piston body and a conical die core body, a spiral flow guide groove is formed on the conical die core body along the conical surface; a wire feeder is fixedly installed in the flat section cavity and the necking cavity, the wire feeder is located inside the die core and coaxially designed, a wire running channel is formed through the axis of the wire feeder, the output end of the wire running channel is tightly combined with the end of the conical die core body and maintained on the same vertical plane; the die is also provided with a ring-shaped flow channel which is communicated with the die cavity; the fixed die is provided with an inlet channel which is communicated with the flat section cavity.

[0008] Optionally, the taper of the conical mold core body is identical to the taper of the mold cavity, the axial length of the conical mold core body is identical to the axial length of the distribution cavity, and the conical mold core body is coaxial with the distribution cavity, the assembly cavity is formed on the fixed mold, the first end of the wire feeding body is located in the assembly cavity and is fixedly installed in the assembly cavity by the support, and the piston body penetrates into the assembly cavity and is in piston sealing cooperation with the penetration position and allows rotation.

[0009] Optionally, the wire feeding body has a conical head, the pen cavity has a conical cavity with an opening, the outer wall of the conical head is tightly fitted with the inner wall of the conical cavity, a plurality of liquid feeding channels are formed on the wire feeding body, the output end opening of the liquid feeding channel is located on the outer wall of the conical head, and the output end is tangent to the outer wall of the conical head and faces the outlet of the conical cavity, and the annular flow channel can be inserted with a flow channel intercepting structure.

[0010] Optionally, the wire feeding channel, the conical cavity opening and the annular flow channel are coaxial, the pen cavity has a rod cavity, the wire feeding body further has a rod part, a rubber plug is fixedly installed on the rod part, and the rubber plug is in piston assembly with the rod cavity.

[0011] Optionally, the flow channel intercepting structure includes a plunger in piston assembly with the inner wall of the annular flow channel, the plunger further has a push rod, and the annular flow channel and the distribution cavity further have a large round corner transition area, the minimum inner diameter of the large round corner transition area is greater than the inner diameter of the annular flow channel, and the plunger can slide to the large round corner transition area.

[0012] Optionally, the cross section of the spiral flow guide groove is arc-shaped, and the arc length of the arc-shaped cross section gradually decreases along the wire feeding direction.

[0013] Optionally, the piston body penetrates into the assembly cavity, a driven gear is fixedly installed on the end of the piston body, a main drive gear meshing with the driven gear is rotatably installed on the assembly cavity, the main drive gear and the driven gear form a speed reduction module, the main drive gear and the driven gear are spur gears, and the sliding stroke of the driven gear on the main drive gear along the axis is greater than the axial length of the conical mold core body.

[0014] Optionally, the optical cable extrusion die further comprises a mold frame, an assembly ring and a mold shell, the mold frame surrounds the outside of the fixed mold and the mold core, the assembly ring is assembled on the outer wall of the die, and the mold shell is assembled outside the assembly ring and is fixedly assembled between the mold frame.

[0015] The present application provides an optical cable extrusion die, which has the following advantages compared with the prior art.

[0016] By designing the spiral flow guide groove, part of the melt can be introduced into the mold cavity to form a distribution and then flow into the annular flow channel through the mold cavity, so that the circumferential pressure and flow are uniform, the flow unevenness at the center and the periphery of the mold cavity is greatly alleviated, the dead angle accumulation is reduced, and the thermal history difference is weakened.

[0017] By designing the gradually reduced arch cross section along the wire feeding direction, the side-in melt can be uniformly spread in the circumferential direction, and the circumferential velocity component is gradually weakened before the outlet end, the residence and welding line development are reduced, and the speed and temperature field consistency of the melt in the annular flow channel are improved.

[0018] By designing the taper of the tapered mold core body to be equal to the taper of the mold cavity, and the axial length of the tapered mold core body to be equal to the axial length of the distribution cavity, the outer wall of the tapered mold core body can be fitted with the inner wall of the distribution cavity through displacement control of the mold core, and the distribution cavity inner wall can be scraped by rotating the mold core, thereby avoiding disassembly.

[0019] By designing the displacement of the mold core, the blockage of the liquid feeding channel is eliminated, at this time the external mold cleaning liquid is pumped into the mold cavity, the flat section cavity and the neck cavity, and soaking and flushing are completed, and then the tapered mold core body is rotated, so that the inner wall of the distribution cavity can be effectively cleaned, and the cleaning liquid also enters the annular flow channel to soak and clean. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic diagram of the external three-dimensional structure of the present application;

[0021] Figure 2 is a schematic diagram of the right view structure of the present application; Figure 1

[0022] Figure 3 is a schematic diagram of the structure of the present application along the A-A section; Figure 2

[0023] Figure 4 is a schematic diagram of the state of the sleeve-shaped mold core after displacement in the present application;

[0024] Figure 5 is a schematic diagram of the internal structure of the combined mold cavity of the present application;

[0025] Figure 6 is a schematic diagram of the structure disassembly and assembly in the present application;

[0026] Figure 7 is a schematic diagram of the three-dimensional structure of the present application from another perspective.

[0027] ​​In the figure: 1, fixed mold; 2, mold core; 3, wire feeding body; 4, die; 5, shunt cavity; 6, annular runner; 7, mold frame; 8, mold shell; 9, wire running channel; 11, liquid feeding channel; 12, assembly ring; 13, plunger. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0029] Please refer to Figures 1 to 7 The present application provides a technical solution: an optical cable extrusion die, comprising:

[0030] The fixed mold 1 and the flat section cavity and the neck cavity inside the fixed mold 1, the fixed mold 1 is assembled with the die 4, the die 4 is designed with the shunt cavity 5 inside, and the shunt cavity 5 is smoothly connected with the narrow mouth of the neck section, and the shunt cavity 5 and the neck section form a mold cavity; the flat section cavity and the neck cavity are installed with the mold core 2, the mold core 2 has a pen cavity inside, the mold core 2 has a piston body and a conical mold core body, and the conical mold core body is provided with a spiral flow guide groove on the conical surface; the flat section cavity and the neck cavity are also fixedly installed with the wire feeding body 3, the wire feeding body 3 is located inside the mold core 2 and coaxially designed with the mold core 2, a wire running channel 9 is provided through the axis of the wire feeding body 3, the output end of the wire running channel 9 is tightly combined with the end of the conical mold core body and maintained on the same vertical plane; the die 4 is also provided with an annular runner 6 which is communicated with the mold cavity; the fixed mold 1 is provided with a feeding channel which is communicated with the flat section cavity.

[0031] In the prior art, the molten material at the neck section is extruded, resulting in better fluidity of the molten material close to the axis, which causes the pressure equalization and flow equalization not to be effectively and high-quality completed before entering the annular runner 6, while in the present application, the feeding channel is a side feeding, which often causes a pressure difference in the circumferential direction, and by designing the spiral flow guide groove, the molten material coming from the axial direction can be evenly spread, pressure equalized and reduced in the circumferential direction, and the welds and stagnation are reduced, specifically, part of the solution is introduced into the mold cavity to form a distribution and reflow, and then the mold cavity is used to evenly distribute to the annular runner 6, thereby realizing the circumferential pressure equalization and flow equalization, which can greatly alleviate the uneven flow condition of the center and the periphery of the mold cavity, secondly, the surface of the conical mold core body is continuously "scanned", the boundary layer is continuously updated, the dead angle accumulation is reduced, thereby reducing the black spots and coking points, and thirdly, the circumferential mixing effect weakens the "thermal history difference", reduces the flow deviation caused by non-uniform viscosity, and the improvement in appearance can reduce the probability of weld mark and sharkskin.

[0032] In the case, the forming of the cavity is designed as a combination, so that when the die is replaced later, the split cavity 5 with different taper can be selected for docking, so as to avoid the difference caused by the flow rate of the fluid according to the different melting materials.

[0033] In a more preferred embodiment, the taper of the tapered core body is equal to the taper of the cavity, the axial length of the tapered core body is equal to the axial length of the split cavity 5, and the tapered core body and the split cavity 5 are coaxial. The assembly cavity is provided on the fixed mold 1, the first end of the wire feeding body 3 is located in the assembly cavity, and the wire feeding body 3 is fixedly installed in the assembly cavity by the support. The piston body penetrates into the assembly cavity, and the piston body and the penetration part form a piston type sealing cooperation and allow rotation. In the prior art, if the melting material or the micro-defect problem occurs on the inner wall of the neck-in section, the melting material flowing slowly at the inner wall of the neck-in section will be even slower, and even a dead zone will occur, which affects the laminar flow effect of the fluid. Therefore, please refer to Figures 2 to 4 In the embodiment, the die core 2 can be displaced into the split cavity 5, and since the two are coaxial, the distance between the outer wall of the tapered core body and the inner wall of the split cavity 5 gradually decreases, realizing the regulation and control of the split and reflow of the melting material. When the inner wall of the neck-in section, that is, the split cavity 5 in the case, since the taper of the tapered core body is equal to the taper of the cavity, and the axial length of the tapered core body is equal to the axial length of the split cavity 5, by controlling the displacement of the die core 2, the outer wall of the tapered core body can be fitted with the inner wall of the split cavity 5. By controlling the rotation of the die core 2, the split cavity 5 can be scraped to avoid disassembly.

[0034] On the basis of the scraping and cleaning embodiment, the wire feeding body 3 has a tapered head, the pen cavity has a tapered cavity with an opening, the outer wall of the tapered head is tightly fitted with the inner wall of the tapered cavity, and a plurality of liquid feeding channels 11 are provided on the wire feeding body 3. The output end opening of the liquid feeding channel 11 is located on the outer wall of the tapered head, and the output end is tangent to the outer wall of the tapered head and faces the outlet of the tapered cavity. The annular flow channel 6 can be inserted with a flow channel intercepting structure. In the embodiment, please refer to Figure 3 and Figure 4 When the die core 2 is displaced, the distance between the outer wall of the tapered head and the inner wall of the tapered cavity is opened, and the blockage of the liquid feeding channel 11 is also removed. At this time, the liquid feeding channel 11 is pumped by external pressure, and the mold cleaning liquid can be pumped into the cavity, the flat section cavity and the neck-in cavity, completing soaking and flushing. In combination with the rotation of the tapered core body, the inner wall of the split cavity 5 can be effectively cleaned. Similarly, the cleaning liquid will also enter the annular flow channel 6 for soaking and cleaning.

[0035] On the basis of the liquid feeding embodiment, the wire feeding channel 9, the tapered cavity opening and the annular flow channel 6 are coaxial. The pen cavity has a rod cavity, and the wire feeding body 3 also has a rod part. A rubber plug is fixedly installed on the rod part, and the rubber plug and the rod cavity are piston assembled.

[0036] On the basis of the liquid inlet embodiment, the flow channel intercepting structure comprises a plunger 13 in piston assembly with the inner wall of the annular flow channel 6, the plunger 13 also has a push rod, and the annular flow channel 6 is provided with a large round corner transition area between the flow dividing cavity 5, the minimum inner diameter of the large round corner transition area is larger than the inner diameter of the annular flow channel 6, and the plunger 13 can slide to the large round corner transition area. Please refer to Figure 4 And its detailed enlarged view, in this embodiment, the plunger 13 can clean the inner wall of the annular flow channel 6 in cooperation with the cleaning liquid, and the plunger 13 can carry out the scraping and cleaning of the annular flow channel 6 after entering the large round corner transition area.

[0037] The plunger 13 can be taken out and taken out during the work of the extrusion die.

[0038] Among the more preferred embodiments, the cross section of the spiral flow guide groove is arcuate, and the arc length of the arcuate cross section gradually decreases along the wire feeding direction. In this embodiment, this design is important. The gradual reduction of the arcuate can uniformly spread the side-in melt in the circumferential direction, and gradually weaken the circumferential velocity component before the outlet end, reduce the residence and welding line development, and improve the consistency of the melt speed and temperature field in the annular flow channel 6. In detail, the upstream arc length is larger, and the equivalent flow width of the groove is larger, so it has stronger circumferential distribution ability, and the melt is quickly spread to the whole circle. The arc length of the downstream arc gradually decreases, the "suction" of the groove to the circumferential flow is weakened, the melt gradually returns to the annular gap main flow, avoids "over supply" at the tail end, and the arc cross section has no sharp angle, the groove bottom is a circular arc transition, and the hanging material position is reduced; axial taper is "downstream closing", which reduces the blind end and tail distance.

[0039] On the basis of the scraping and cleaning embodiment, the end of the piston body is fixedly installed with a driven gear, the assembly cavity is rotatably installed with a main drive gear meshing with the driven gear, and the main drive gear and the driven gear form a speed reduction module. The main drive gear and the driven gear are both spur gears, and the sliding stroke of the driven gear on the main drive gear along the axis is greater than the axis length of the tapered die core body.

[0040] Further, the optical cable extrusion die further comprises a die frame 7, an assembly ring 12 and a die shell 8. The die frame 7 surrounds the outside of the fixed die 1 and the die core 2, the assembly ring 12 is assembled on the outer wall of the die 4, and the die shell 8 is assembled outside the assembly ring 12 and forms a fixed assembly between the die frame 7.

[0041] By cooperating the above structures, through spiral flow guide, coaxial adjustable taper core, combined die cavity and in-situ cleaning, circumferential uniform pressure and flow under side feeding, outlet field consistency, free cleaning and rapid changeover are realized, and the forming stability and appearance quality are significantly improved.

[0042] The standard parts used in the embodiment can be directly purchased from the market, and the non-standard structural parts according to the description and drawings can also be directly processed according to the existing technical knowledge without any doubt, and the connection mode of each part adopts the mature conventional means in the existing technology, and the machinery, parts and equipment adopt the conventional models in the existing technology, so the specific description is not made here.

[0043] Although the embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made thereto without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. An optical cable extrusion die characterized by: It includes: The fixed mold (1) and its internal flat section cavity and neck cavity, the fixed mold (1) is equipped with a die head (4), the die head (4) is designed with a shunt cavity (5) inside, and the shunt cavity (5) and the narrow mouth of the neck section are smoothly connected, and the shunt cavity (5) and the neck section form a mold cavity; The flat section cavity and the neck cavity are provided with a mold core (2), the mold core (2) has a pen cavity inside, the mold core (2) has a piston body and a conical mold core body, a spiral flow guide groove is formed on the conical mold core body along the conical surface; The flat section cavity and the neck cavity are also fixedly provided with a wire feeding body (3), the wire feeding body (3) is located inside the mold core (2) and coaxially designed with the mold core (2), a wire passing channel (9) is formed through the wire feeding body (3), the output end of the wire passing channel (9) is closely combined with the end of the conical mold core body and maintained on the same vertical plane; The die head (4) is also provided with an annular flow channel (6) which is communicated with the mold cavity; The fixed mold (1) is provided with a feeding channel which is communicated with the flat section cavity; The taper of the conical mold core body is equal to the taper of the mold cavity, the axial length of the conical mold core body is equal to the axial length of the shunt cavity (5), and the conical mold core body is coaxially designed with the shunt cavity (5), the fixed mold (1) is provided with an assembly cavity, the first end of the wire feeding body (3) is located in the assembly cavity and is fixedly installed in the assembly cavity by a support, the piston body penetrates into the assembly cavity, and the piston body and the penetration part form a piston type sealing cooperation and allow rotation; The wire feeding body (3) has a conical head, the pen cavity has a conical cavity with an opening, the outer wall of the conical head is closely combined with the inner wall of the conical cavity, a plurality of liquid feeding channels (11) are formed through the wire feeding body (3), the output end opening of the liquid feeding channel (11) is located on the outer wall of the conical head, and the output end is tangent to the outer wall of the conical head and faces the outlet of the conical cavity, the annular flow channel (6) can be inserted into the flow channel intercepting structure.

2. The optical cable extrusion die of claim 1, wherein: The wire passing channel (9), the conical cavity opening and the annular flow channel (6) are coaxially designed, the pen cavity has a rod cavity, the wire feeding body (3) also has a rod part, a rubber plug is fixedly installed on the rod part, and the rubber plug and the rod cavity are piston assembled.

3. The optical cable extrusion die of claim 1, wherein: The flow channel intercepting structure includes a plunger (13) which is piston assembled with the inner wall of the annular flow channel (6), the plunger (13) also has a push rod, the annular flow channel (6) and the shunt cavity (5) also have a large round corner transition area, the minimum inner diameter of the large round corner transition area is greater than the inner diameter of the annular flow channel (6), and the plunger (13) can slide to the large round corner transition area.

4. The optical cable extrusion die of claim 1, wherein: The slot cross section of the spiral flow guide groove is arc-shaped, and the arc length of the arc-shaped cross section gradually decreases along the wire feeding direction.

5. The optical cable extrusion die of claim 1, wherein: The piston body penetrates into the assembly cavity, a driven gear is fixedly installed on the end of the piston body, a main drive gear which is engaged with the driven gear is rotatably installed on the assembly cavity, and the main drive gear and the driven gear form a speed reduction module, the main drive gear and the driven gear are spur gears, and the sliding stroke of the driven gear on the main drive gear along the axis is greater than the axial length of the conical mold core body.

6. The optical cable extrusion die of any of claims 1-5, wherein: The optical cable extrusion die further comprises a die frame (7), an assembly ring (12) and a die shell (8), the die frame (7) surrounds the outside of the fixed die (1) and the die core (2), the assembly ring (12) is assembled on the outer wall of the die head (4), and the die shell (8) is assembled outside the assembly ring (12) and forms a fixed assembly between the die frame (7).

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