A cable two-color extrusion die

Abstract

The utility model belongs to cable manufacturing equipment field discloses a kind of cable bicolour extrusion moulds. The cable bicolour extrusion mould includes die sleeve assembly and mould core, die sleeve assembly and mould core are spaced apart along the axial direction and form first feed channel, die sleeve assembly includes the outer die, middle die and inner die sequentially arranged from outside to inside, the sidewall of outer die is equipped with feed hole, the sidewall of middle die is equipped with the fan-shaped slot being communicated with feed hole along the axial direction, the vertex end of fan-shaped slot is directly opposite feed hole, the unfolded end extends to the end face of middle die, the fan-shaped slot and part outer die inner wall form second feed channel, second feed channel is communicated with first feed channel, inner die is detachably connected with middle die, inner die inner wall and mould core outer wall cooperate and form the forming surface of first feed channel, to solve the problem that existing bicolour strip injection method relies on special belt injection orifice machine head, and the problem of insufficient flexibility is solved, the adaptability of cable bicolour extrusion mould to different production needs is improved, while the stability and accuracy of bicolour strip injection are guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of cable manufacturing equipment, and in particular to a two-color extrusion die for cables. Background Technology

[0002] With the rapid development of the power industry and the increasing demands for reliable power supply, cross-linked polyethylene (XLPE) insulated power cables, due to their superior performance, have become the most widely used cable type, covering all voltage levels from low voltage and medium-high voltage to ultra-high voltage. In practical applications, some users, due to the special nature of the laying environment or to improve cable identification efficiency, have requested the injection of two-color stripes onto the surface of the cable's outer sheath. Currently, the conventional method in the industry to achieve this is to set injection holes and install color-separation rings on the machine head. However, this method requires a dedicated machine head with injection holes, resulting in poor flexibility in the production process. Utility Model Content

[0003] The purpose of this utility model is to provide a cable two-color extrusion die to solve the problem that the existing two-color strip injection method relies on a special die head with injection holes and lacks flexibility, improve the adaptability of the cable two-color extrusion die to different production needs, and at the same time ensure the stability and accuracy of two-color strip injection.

[0004] To achieve this objective, the present invention adopts the following technical solution:

[0005] A two-color extrusion die for cables includes a die sleeve assembly and a die core. The die sleeve assembly and the die core are spaced apart along the axial direction to form a first feeding channel. The die sleeve assembly includes an outer die, a middle die, and an inner die arranged sequentially from the outside to the inside. The side wall of the outer die is provided with a feeding hole. The side wall of the middle die is provided with a fan-shaped groove along the axial direction that communicates with the feeding hole. The apex of the fan-shaped groove faces the feeding hole. The unfolded end of the fan-shaped groove extends to the end face of the middle die. The fan-shaped groove and part of the inner wall of the outer die form a second feeding channel. The second feeding channel communicates with the first feeding channel. The inner die and the middle die are detachably connected. The inner wall of the inner die and the outer wall of the die core cooperate to form the forming surface of the first feeding channel.

[0006] As an alternative to a two-color extrusion die for cables, the depth of the fan-shaped groove gradually decreases from the apex to the unfolded end, and the bottom wall of the fan-shaped groove is spaced apart from the inner wall of the outer die.

[0007] As an alternative to a two-color extrusion die for cables, the apex of the fan-shaped groove is provided with an arc segment, the radius of which matches the radius of the feed hole.

[0008] As an alternative to a two-color extrusion die for cables, the die core has an outer conical surface at one end facing the die sleeve assembly, and the die sleeve assembly has an inner conical surface that mates with it at the corresponding end, forming the first feeding channel between the outer conical surface and the inner conical surface.

[0009] As an alternative to a two-color extrusion die for cables, the inner conical surface is formed by a smooth transition between the contact surfaces of the outer die, the middle die, and the inner die.

[0010] As an alternative solution for a two-color extrusion die for cables, the inner wall of the outer die is provided with a first limiting protrusion extending circumferentially, and the outer wall of the middle die is provided with a corresponding first limiting groove. The first limiting protrusion and the first limiting groove cooperate to limit the axial displacement of the middle die along the outer die.

[0011] As an alternative solution for a two-color extrusion die for cables, the outer wall of the middle die is provided with a second limiting groove communicating with the first limiting groove along the axial direction, and the inner wall of the outer die is provided with a limiting pin. The limiting pin is slidably connected with the second limiting groove to limit the circumferential displacement of the middle die relative to the outer die.

[0012] As an alternative solution for a two-color extrusion die for cables, the inner wall of the middle die is provided with a second circumferentially extending limiting protrusion, and the outer wall of the inner die is provided with a corresponding third limiting groove. The second limiting protrusion and the third limiting groove cooperate to limit the axial displacement of the inner die along the middle die.

[0013] As an alternative to a two-color extrusion die for cables, the inner diameter of the middle die gradually expands from the second limiting protrusion toward the direction away from the inner die.

[0014] As an alternative to a two-color extrusion die for cables, the die core has an axially oriented discharge channel that passes through both end faces for the cable core to pass through. The inner diameter of the discharge channel gradually decreases in the direction close to the die assembly.

[0015] Beneficial effects:

[0016] This invention provides a two-color extrusion die for cables. A first feeding channel is formed by axially spaced die sleeve components and die cores. A three-layer nested structure of outer die, middle die, and inner die, combined with a fan-shaped groove design, enables efficient co-extrusion molding of two-color cables. The second feeding channel, formed by the inner wall of the outer die and the fan-shaped groove of the middle die, intersects with the first feeding channel to create a three-dimensional material flow path, ensuring precise interface control and fusion of the two colors during extrusion. In particular, the apex alignment design and extended structure of the fan-shaped groove in the middle die optimize the uniformity of material flow distribution. The detachable connection structure between the inner and middle dies enhances the adaptability of the two-color extrusion die; the extrusion diameter can be adjusted simply by replacing the inner die, significantly improving the die's versatility and flexibility. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the cable two-color extrusion die provided in this embodiment of the utility model;

[0018] Figure 2 This is a schematic diagram of the structure of the outer mold provided in this embodiment of the utility model;

[0019] Figure 3 This is a first schematic diagram of the intermediate mold provided in this embodiment of the utility model;

[0020] Figure 4 This is a second schematic diagram of the intermediate mold provided in this embodiment of the utility model;

[0021] Figure 5 This is a schematic diagram of the structure of the inner mold provided in this embodiment of the utility model.

[0022] In the picture:

[0023] 1. Mold assembly;

[0024] 11. Outer mold; 111. Feed hole; 112. First limiting protrusion; 113. Limiting pin;

[0025] 12. Middle mold; 121. Sector groove; 122. First limiting groove; 123. Second limiting groove; 124. Second limiting protrusion; 1211. Vertex end; 1212. Unfolded end; 1213. Arc segment;

[0026] 13. Inner mold; 131. Third limiting groove; 14. Second feeding channel; 15. Inner conical surface;

[0027] 2. Mold core; 21. Outer conical surface; 22. Material discharge channel;

[0028] 3. First material feeding channel. Detailed Implementation

[0029] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, not the entire structure.

[0030] In the description of this utility model, unless otherwise expressly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part of the device. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0032] In the description of this embodiment, the terms "upper" and "lower," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0033] This embodiment provides a two-color extrusion die for cables, such as... Figure 1 As shown, the cable two-color extrusion die includes a die sleeve assembly 1 and a die core 2. The die sleeve assembly 1 and the die core 2 are spaced apart along the axial direction to form a first feeding channel 3. The die sleeve assembly 1 includes an outer die 11, a middle die 12 and an inner die 13 arranged sequentially from the outside to the inside. The side wall of the outer die 11 is provided with a feeding hole 111. The side wall of the middle die 12 is provided with a fan-shaped groove 121 that communicates with the feeding hole 111 along the axial direction. The apex 1211 of the fan-shaped groove 121 is directly opposite the feeding hole 111. The unfolded end 1212 of the fan-shaped groove 121 extends to the end face of the middle die 12. The fan-shaped groove 121 and part of the inner wall of the outer die 11 form a second feeding channel 14. The second feeding channel 14 communicates with the first feeding channel 3. The inner die 13 and the middle die 12 are detachably connected. The inner wall of the inner die 13 and the outer wall of the die core 2 cooperate to form the forming surface of the first feeding channel 3.

[0034] This two-color cable extrusion die forms a first feeding channel 3 through the axial spacing of the die sleeve assembly 1 and the die core 2. It employs a three-layer nested structure of outer die 11, middle die 12, and inner die 13, combined with a fan-shaped groove 121 design, achieving efficient co-extrusion molding of the two-color cable. The second feeding channel 14, formed by a portion of the inner wall of the outer die 11 and the fan-shaped groove 121 of the middle die 12, forms a three-dimensional material flow path with the first feeding channel 3, ensuring precise interface control and fusion of the two color materials (primary and secondary color materials) during extrusion. In particular, the alignment design of the apex 1211 of the fan-shaped groove 121 of the middle die 12 and the extension structure of the unfolded end 1212 optimize the uniformity of material flow distribution. The detachable connection structure between the inner die 13 and the middle die 12 enhances the adaptability of the two-color cable extrusion die; the extrusion diameter can be adjusted simply by replacing the inner die 13, significantly improving the versatility and flexibility of the two-color cable extrusion die.

[0035] Specifically, the die sleeve assembly 1 and the die core 2 together form a ring structure. The annular gap between them forms a first feeding channel 3 for transmitting the main colorant, which is the primary color of the cable's outer sheath surface, typically black. The second feeding channel 14 is responsible for transmitting the auxiliary colorant, which is the secondary color of the cable's outer sheath surface, typically red. After entering the second feeding channel 14 through the feeding hole 111, the auxiliary colorant flows into the first feeding channel 3 and merges with the main colorant, ultimately being extruded together. During the extrusion process, the main and auxiliary colorants maintain their respective shapes and distributions, ultimately forming a cable outer sheath that combines both the primary and auxiliary colors, such as clearly visible red marking lines on a black base.

[0036] like Figure 1 As shown, the depth of the fan-shaped groove 121 gradually decreases from the apex 1211 to the unfolded end 1212, and the bottom wall of the fan-shaped groove 121 is spaced apart from the inner wall of the outer mold 11. As the depth of the fan-shaped groove 121 gradually decreases from the apex 1211 to the unfolded end 1212, its width naturally widens due to the fan-shaped structure. However, the decrease in depth exceeds the increase in width, ensuring that the cross-sectional area of ​​the entire fan-shaped groove 121 (determined by both depth and width) gradually decreases. With a stable flow rate of the auxiliary colorant, as the space gradually narrows, the flow rate of the auxiliary colorant gradually increases, allowing it to approach the first feeding channel 3 and become closer to the flow rate of the main colorant. If the difference in flow rates is too large, the auxiliary colorant is easily dispersed or deformed by the main colorant, resulting in blurred or broken auxiliary color lines. Gradual matching of flow rates avoids this problem, ensuring that the main and auxiliary colorants maintain clear boundaries and do not mix. Meanwhile, the bottom wall of the fan-shaped groove 121 does not directly contact the inner wall of the outer mold 11, leaving a gap. This can prevent the flow rate from being disrupted by sudden changes in frictional resistance when the auxiliary color material flows. It can also provide a buffer space to prevent the auxiliary color material from being over-compressed and causing local accumulation or sudden changes in flow rate. Ultimately, it ensures that the lines of the auxiliary color material are continuous and clear after extrusion, and that the boundary with the main color material is distinct.

[0037] like Figure 1 and Figure 4 As shown, the apex 1211 of the fan-shaped groove 121 has an arc segment 1213, the radius of which matches the radius of the feed hole 111, thereby achieving a smooth transition of the auxiliary colorant from the feed hole 111 to the fan-shaped groove 121. When the auxiliary colorant flows into the fan-shaped groove 121 from the feed hole 111, the matching radius avoids sharp corners or steps caused by abrupt changes in the channel shape, allowing the auxiliary colorant to flow along a continuous curved surface, preventing the auxiliary colorant from stagnating or accumulating at corners, and ensuring uniform transmission of the material flow rate. At the same time, the smooth transition reduces flow resistance, resulting in less pressure loss when the auxiliary colorant enters the fan-shaped groove 121, maintaining a stable flow rate and velocity. If the radius of the arc segment 1213 does not match the feed hole 111, such as if the arc of the arc segment 1213 is too small or there is a right angle transition, the flow direction of the auxiliary color material will suddenly turn at the junction, causing local pressure fluctuations, which may cause the flow rate of the auxiliary color material to fluctuate, thus affecting the shape stability when the main color material is subsequently incorporated.

[0038] like Figure 1 As shown, the mold core 2 has an outer conical surface 21 facing the mold sleeve assembly 1, and the corresponding end of the mold sleeve assembly 1 has an inner conical surface 15 that mates with it. A first feeding channel 3 is formed between the outer conical surface 21 and the inner conical surface 15. This conical gap design can guide the main color material to form a gradual flow state along the axial direction. As the conical surface gradually contracts, the cross-sectional area of ​​the first feeding channel 3 changes in a regular manner, so that the flow velocity of the main color material increases steadily during the flow process, avoiding turbulence or pressure fluctuations caused by abrupt changes in the shape of the first feeding channel 3. This mating method can guide the main color material to uniformly adhere to the wall of the first feeding channel 3 through the guiding effect of the conical surface, ensuring the uniform distribution of the main color material on the annular cross section and reducing local accumulation or thinning. At the same time, the high-precision fitting of the conical surface can ensure that the gap of the first feeding channel 3 is uniform, the flow velocity of the main color material is stable and uniformly distributed, and it can more accurately receive the auxiliary color material, avoiding the blurring of the boundary between the main and auxiliary colors due to the turbulent flow of the main color material, ultimately helping the two to form a regular co-extrusion structure without mixing.

[0039] like Figure 1As shown, the inner conical surface 15 is formed by the smooth transition of the contact end faces of the outer mold 11, the middle mold 12, and the inner mold 13. When the contact end faces of the three molds achieve a smooth transition, it can avoid interference with the flow of the main color material due to steps, gaps, or sharp edges at the joint. When the main color material flows along the conical surface, it can be uniformly advanced along the continuous curved surface without generating local obstruction or eddies at the joint, thereby maintaining the stability of the flow rate and the uniformity of the material distribution. At the same time, the smooth transition of the inner conical surface 15 and the outer conical surface 21 of the mold core 2 have higher fitting precision, which can ensure that the size of the annular gap (i.e., the first feeding channel 3) between the two is uniform. If there is an uneven defect at the joint, it will cause the channel gap to widen or narrow locally, causing a sudden change in the flow rate of the main color material, which will disrupt the flow field balance when it merges with the auxiliary color material, and may cause disorder of the main and auxiliary color boundaries. The smooth transition of the inner conical surface 15 allows the main colorant to flow in a stable channel environment, providing a uniform flow field foundation for the subsequent auxiliary colorant to flow in through the fan-shaped groove 121, and ultimately ensuring that the main and auxiliary colorants achieve regular co-extrusion molding without mixing.

[0040] like Figure 1 , Figure 2 and Figure 3 As shown, the inner wall of the outer mold 11 is provided with a circumferentially extending first limiting protrusion 112, and the outer wall of the middle mold 12 is provided with a corresponding first limiting groove 122. The first limiting protrusion 112 and the first limiting groove 122 cooperate to limit the axial displacement of the middle mold 12 along the outer mold 11. When the main pigment flows in the first feeding channel 3, it will generate a continuous axial impact force. If there is no effective limiting, the middle mold 12 is likely to be displaced along the axial direction of the outer mold 11 under the action of this impact force. Once the middle mold 12 is displaced, the inner conical surface 15 formed by its contact end face with the outer mold 11 and the inner mold 13 will be misaligned, which will damage the structural integrity of the first feeding channel 3. The channel gap of the first feeding channel 3 may become locally wider or narrower. This will not only disrupt the stable flow of the main pigment, causing fluctuations in its flow rate and pressure, but may also affect the path stability of the auxiliary pigment flowing into the first feeding channel 3 through the fan-shaped groove 121. The tight fit between the first limiting protrusion 112 and the first limiting groove 122 can firmly lock the position of the middle mold 12, effectively resist the impact of the main color material, ensure that the inner conical surface 15 maintains a smooth transition and complete shape, maintain the dimensional stability of the first feeding channel 3, thereby ensuring the smooth flow of the main color material, and also providing a reliable structural foundation for the stable co-extrusion of the auxiliary color material and the main color material, ensuring the regularity of the final molding effect.

[0041] like Figure 1 , Figure 2 and Figure 3As shown, the outer wall of the middle mold 12 is provided with a second limiting groove 123 communicating with the first limiting groove 122 along the axial direction. The inner wall of the outer mold 11 is provided with a limiting pin 113. The limiting pin 113 is slidably connected to the second limiting groove 123 to limit the circumferential displacement of the middle mold 12 relative to the outer mold 11. When the main colorant flows in the first feeding channel 3, in addition to generating axial impact force, it will also generate circumferential friction force due to movement along the annular channel, which may cause the middle mold 12 to rotate slightly with the material flow direction. If the middle mold 12 rotates circumferentially, the inner conical surface 15 formed by its splicing with the outer mold 11 and the inner mold 13 will be misaligned, destroying the smooth continuity of the conical surface, causing the flow of the main colorant to be obstructed, and thus causing pressure fluctuations. A more direct impact is that the position of the sector groove 121 will shift as the intermediate mold 12 rotates: the sector groove 121 is the key path for the auxiliary color material to enter the first channel from the feed hole 111. Its circumferential position needs to be precisely aligned with the feed hole 111. If rotation occurs, the flow angle of the auxiliary color material will deviate from the preset direction, which may cause an oblique impact with the main color material flow, destroying the boundary clarity between the two, or even causing the auxiliary color material to be scattered by the main color material. The cooperation between the limiting pin 113 and the second limiting groove 123 ensures that the sector groove 121 is always aligned with the preset entry point of the feed hole 111 and the first channel, allowing the auxiliary color material to flow smoothly in the predetermined direction, while maintaining the integrity of the inner cone surface 15 and ensuring the stable flow of the main color material along the continuous curved surface. Ultimately, under the dual action of axial limiting (the first limiting protrusion 112 and the groove) and circumferential limiting, the intermediate die 12 is completely fixed in the preset position, effectively resisting the impact and movement of the main color material, and providing a reliable structural guarantee for the regular shape and clear boundaries during co-extrusion of two materials. In this embodiment, the second limiting groove 123 and the fan-shaped groove 121 are arranged opposite to each other to avoid interference.

[0042] like Figure 1 , Figure 3 and Figure 5 As shown, the inner wall of the intermediate mold 12 is provided with a second circumferentially extending limiting protrusion 124, and the outer wall of the inner mold 13 is provided with a corresponding third limiting groove 131. The second limiting protrusion 124 and the third limiting groove 131 cooperate to limit the axial displacement of the inner mold 13 along the intermediate mold 12. When the main colorant flows in the first feeding channel 3, it will generate an axial impact force. If the inner mold 13 lacks axial restraint, it may shift axially along the intermediate mold 12 under the action of the impact force, resulting in steps or gaps at the joint with the intermediate mold 12, which will disrupt the smooth transition of the inner conical surface 15. This will directly interfere with the stable flow of the main colorant, causing flow rate fluctuations and pressure disturbances, and may even lead to uneven distribution of the main colorant due to abrupt changes in the channel shape.

[0043] like Figure 1 and Figure 3As shown, the inner diameter of the intermediate mold 12 gradually expands from the second limiting protrusion 124 away from the inner mold 13. When the cable moves away from the inner mold 13 after forming, the gradually expanding inner diameter gradually increases the gap between the inner wall of the intermediate mold 12 and the outer surface of the cable, avoiding continuous contact friction that may occur due to fixed channel dimensions. If the inner diameter of the intermediate mold 12 remains unchanged, the outer sheath of the formed cable may be in long-term contact with the inner wall of the intermediate mold 12, generating friction during movement. This may not only wear down the surface of the outer sheath and affect its appearance, but also interfere with the uniform movement of the cable due to frictional resistance, leading to disordered extrusion rhythm. The gradually expanding design, by gradually increasing the gap, allows the cable to gradually detach from the contact with the inner wall of the intermediate mold 12 after leaving the area affected by the inner mold 13, reducing the risk of frictional damage. At the same time, it ensures that the cable is subjected to more stable force during movement, providing conditions for subsequent stable extrusion, and indirectly ensuring that the boundaries and shapes of the main and auxiliary pigments are not interfered with by contact friction.

[0044] like Figure 1 As shown, the die core 2 has a discharge channel 22 extending through both end faces along the axial direction for the cable core to pass through. The inner diameter of the discharge channel 22 gradually decreases towards the die assembly 1. The positional accuracy of the core directly determines the uniformity of the outer sheath thickness (formed by co-extrusion of main and auxiliary pigments). If the inner diameter of the discharge channel 22 remains unchanged or suddenly shrinks, the core may wobble due to insufficient constraint, resulting in localized excessively thick or thin outer sheaths. The tapered design, through continuous and gentle constraint, ensures that the core is always centered in the discharge channel 22, providing a reference for the uniform wrapping of the outer sheath. At the same time, the tapered structure reduces frictional damage between the core and the inner wall of the discharge channel 22. During the movement of the core, if the inner diameter of the discharge channel 22 changes abruptly, concentrated friction may occur at the corners, causing scratches on the core surface. The gradually changing inner diameter allows the contact force between the core and the inner wall of the discharge channel 22 to change gradually, reducing the risk of localized wear. In addition, the stable position of the wire core provides a uniform surrounding space for the main color material in the first feeding channel 3, so that the main color material can flow smoothly along the outer periphery of the wire core. After the auxiliary color material is incorporated, it can also form a regular auxiliary color mark in the preset position, ultimately ensuring the forming accuracy and appearance quality of the overall cable structure.

[0045] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. Those skilled in the art can make various obvious changes, readjustments, and substitutions without departing from the protection scope of this utility model. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A two-color extrusion die for cables, characterized in that, The device includes a mold sleeve assembly (1) and a mold core (2). The mold sleeve assembly (1) and the mold core (2) are spaced apart along the axial direction to form a first feeding channel (3). The mold sleeve assembly (1) includes an outer mold (11), a middle mold (12), and an inner mold (13) arranged sequentially from the outside to the inside. The side wall of the outer mold (11) is provided with a feeding hole (111). The side wall of the middle mold (12) is provided with a fan-shaped groove (121) along the axial direction that communicates with the feeding hole (111). The apex (1211) of the fan-shaped groove (121) is... Facing the feeding hole (111), the unfolded end (1212) of the fan-shaped groove (121) extends to the end face of the middle mold (12). The fan-shaped groove (121) and part of the inner wall of the outer mold (11) form a second feeding channel (14). The second feeding channel (14) is connected to the first feeding channel (3). The inner mold (13) is detachably connected to the middle mold (12). The inner wall of the inner mold (13) and the outer wall of the mold core (2) cooperate to form the forming surface of the first feeding channel (3).

2. The cable two-color extrusion die according to claim 1, characterized in that, The depth of the fan-shaped groove (121) gradually decreases from the vertex end (1211) to the unfolded end (1212), and the bottom wall of the fan-shaped groove (121) is spaced apart from the inner wall of the outer mold (11).

3. The cable two-color extrusion die according to claim 2, characterized in that, The vertex end (1211) of the fan-shaped groove (121) is provided with an arc segment (1213), the radius of which matches the radius of the feeding hole (111).

4. The cable two-color extrusion die according to claim 1, characterized in that, The mold core (2) has an outer conical surface (21) at one end facing the mold sleeve assembly (1), and the mold sleeve assembly (1) has an inner conical surface (15) that cooperates with it at the corresponding end. The first feeding channel (3) is formed between the outer conical surface (21) and the inner conical surface (15).

5. The cable two-color extrusion die according to claim 4, characterized in that, The inner conical surface (15) is formed by a smooth transition between the contact surfaces of the outer mold (11), the middle mold (12) and the inner mold (13).

6. The cable two-color extrusion die according to claim 1, characterized in that, The inner wall of the outer mold (11) is provided with a first limiting protrusion (112) extending circumferentially, and the outer wall of the middle mold (12) is provided with a corresponding first limiting groove (122). The first limiting protrusion (112) cooperates with the first limiting groove (122) to limit the axial displacement of the middle mold (12) along the outer mold (11).

7. The cable two-color extrusion die according to claim 6, characterized in that, The outer wall of the middle mold (12) is provided with a second limiting groove (123) communicating with the first limiting groove (122) along the axial direction. The inner wall of the outer mold (11) is provided with a limiting pin (113). The limiting pin (113) is slidably connected with the second limiting groove (123) to limit the circumferential displacement of the middle mold (12) relative to the outer mold (11).

8. The cable two-color extrusion die according to claim 1, characterized in that, The inner wall of the middle mold (12) is provided with a second limiting protrusion (124) extending circumferentially, and the outer wall of the inner mold (13) is provided with a corresponding third limiting groove (131). The second limiting protrusion (124) cooperates with the third limiting groove (131) to limit the axial displacement of the inner mold (13) along the middle mold (12).

9. The cable two-color extrusion die according to claim 8, characterized in that, The inner diameter of the middle mold (12) gradually expands from the second limiting protrusion (124) toward the direction away from the inner mold (13).

10. The cable two-color extrusion die according to any one of claims 1-9, characterized in that, The mold core (2) is provided with a discharge channel (22) that passes through both end faces along the axial direction for the cable core to pass through. The inner diameter of the discharge channel (22) gradually decreases in the direction close to the mold assembly (1).

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