Double-layer co-extrusion injection mold for optical cable processing and injection molding method

Abstract

The double-layer co-extrusion injection mold for the optical cable comprises a mold body, an inner-layer material inlet is formed in one side of the mold body, a forming outlet is formed in the other side of the mold body, the inner-layer material inlet and the forming outlet are oppositely formed, and an outer-layer flow guide groove is formed in the outer layer of the mold body. The extrusion runner is arranged on the inner layer of the forming outlet; the injection type channel is arranged on the inner layer of the mold body and enables the outer layer flow guide groove to be communicated with the extrusion runner. According to the mold, two materials in a molten state can be effectively isolated, the effect that the two materials cover the optoelectronic unit internally and externally at the same time is achieved, the use amount of the outer-layer thermoplastic material is effectively controlled, the two materials in the molten state can be effectively isolated by adopting the mold, the use amount of the outer-layer material is effectively controlled, and the production efficiency is improved. The production speed of the optical cable is higher, the equipment investment is less, the material loss is less, the cost control is better, and the mixing degree of the inner and outer layers of materials is lower.

Description

Technical Field

[0001] The invention relates to the technical field of molds, and in particular to a double-layer co-extrusion injection mold and an injection molding method for optical cable processing. Background Art

[0002] Double-layer co-extruded optical cable is a communication optical cable with a double-layer material sheath. This process is completed through one extrusion in the same process. It can extrude two thermoplastic materials simultaneously outside the cable core optical unit of the optical cable to form an optical cable protective layer composed of two layers of materials. This technology has not only been widely used abroad, but has also begun to be adopted by some larger domestic manufacturers. However, the common double-layer co-extrusion process in the industry is now achieved through the linkage of the diverter, the main machine, and the auxiliary machine. When the inner layer material and the outer layer material converge, they are in the same processing temperature and pressure environment. It is inevitable that the two molten materials will be mixed in the extruder. In addition, the existing process can only control the amount of outer layer material by controlling the auxiliary machine, and the control mode is single and the control difficulty is high.

[0003] Therefore, a double-layer co-extrusion injection mold and an injection molding method for optical cable processing are needed to solve the shortcomings of the prior art. Summary of the invention

[0004] To this end, the technical problem to be solved by the present invention is to overcome the problem of mixing of two molten materials during the optical cable injection molding process in the prior art, and to provide a double-layer co-extrusion injection mold and injection molding method for optical cable processing, which can effectively isolate the two materials in the molten state and effectively control the amount of outer layer material. The use of this mold can make the production speed of optical cables faster, with less equipment investment, less material loss, better cost control, and lower mixing degree of the inner and outer layer materials.

[0005] In the first aspect, in order to solve the above-mentioned technical problems, the present invention provides a double-layer co-extrusion injection mold for optical cables, including a mold body, on which an inner layer material inlet, an outer layer guide groove, an injection channel, an extrusion flow channel and a molding outlet are provided. The inner layer material inlet is arranged on one side of the mold body, and the molding outlet is arranged on the other side of the mold body, and the inner layer material inlet is arranged opposite to the molding outlet, the outer layer guide groove is arranged on the outer layer of the mold body, and the extrusion flow channel is arranged on the inner layer of the molding outlet; the injection channel is arranged on the inner layer of the mold body to connect the outer layer guide groove and the extrusion flow channel.

[0006] In one embodiment of the present invention, the extrusion flow channel is annular. By adopting an annular extrusion flow channel, the depth of the flow channel is controlled during mold design so that the depth of the extrusion flow channel is appropriate, the amount of outer layer thermoplastic material can be limited, and the thickness of the outer layer material extrusion molding can be controlled to a certain extent. It is effectively combined with auxiliary machine control, more flexible, and can achieve better cost control.

[0007] In one embodiment of the present invention, the injection channels include at least four and are evenly distributed along the circumference of the extrusion flow channel. At least four injection channels are evenly distributed on the circumference of the extrusion flow channel, which can better balance the extrusion pressure.

[0008] In one embodiment of the present invention, an annular buffer space is provided at the injection port of the injection channel. An appropriately enlarged annular space is provided at the injection port of the injection channel, which can serve as a buffer and is not prone to accumulation of thermoplastic material.

[0009] In one embodiment of the present invention, the injection port of the injection channel is gradually reduced from large to small. This design can produce better extrusion pressure for thermoplastic materials.

[0010] In one embodiment of the present invention, a transition inlet is provided between the outer layer guide groove and the injection channel, and a rounded corner is provided at the transition inlet. The transition inlet adopts a smooth rounded corner transition, and the rounded corner has a certain inclination angle to guide the thermoplastic material to flow toward the injection channel.

[0011] In one embodiment of the present invention, the inner wall of the inner layer material inlet is provided with a guide surface, and the guide surface is conical.

[0012] In one embodiment of the present invention, the inner wall of the outer guide groove is arc-shaped. The outer guide groove is evenly arranged on the outer layer of the mold body, and the pressure is more easily balanced. The inner wall surface of the outer guide groove is smooth, and the molten thermoplastic molding material is more likely to flow.

[0013] In one embodiment of the present invention, the forming surface of the forming outlet is in a bell-mouth shape.

[0014] In one embodiment of the present invention, the size of the injection channel can be customized according to the requirements of different products. The size of the injection channel can be adjusted according to the requirements of different products during mold processing.

[0015] In one embodiment of the present invention, the depth of the extrusion flow channel can limit the amount of thermoplastic material used in the outer layer, thereby achieving better cost control;

[0016] In the second aspect, in order to solve the above-mentioned technical problems, the present invention provides an injection molding method, which is implemented by the double-layer co-extrusion injection mold for optical cables described in the first aspect. The injection molding method is specifically as follows: the inner layer thermoplastic material and the outer layer thermoplastic material are respectively injected into the inner layer material inlet and the outer layer guide groove, the outer layer thermoplastic material enters the extrusion flow channel by injection through the outer layer guide groove, the outer layer thermoplastic material is filled in the extrusion flow channel, and the extrusion flow channel covers the outer layer thermoplastic material on the surface of the preliminarily formed inner layer thermoplastic material, thereby realizing the one-piece molding of the two thermoplastic materials.

[0017] The above technical solution of the present invention has the following beneficial effects compared with the prior art:

[0018] The double-layer co-extrusion injection mold and injection molding method for optical cable processing described in the present invention can effectively isolate two materials in a molten state, achieve the effect of two materials, one inside and one outside, covering the optoelectronic unit at the same time, and effectively control the amount of outer thermoplastic material. The use of this mold makes the production speed of optical cables faster, with less equipment investment, less material loss, better cost control, and lower mixing degree of inner and outer materials. After the outer thermoplastic material enters the outer guide groove, it enters the extrusion flow channel by injection, so that the outer thermoplastic material is extruded on the surface of the inner thermoplastic material, realizing the integrated molding of the two thermoplastic materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0020] Figure 1 This is a schematic diagram of the outer layer structure of a double-layer co-extrusion injection mold for optical cables in a preferred embodiment 1 of the present invention;

[0021] Figure 2 for Figure 1 A cross-sectional schematic diagram of a double-layer co-extrusion injection mold for an optical cable is shown;

[0022] Explanation of the reference numerals in the specification: 1. Outer guide groove; 2. Transition inlet; 3. Buffer space; 4. Injection channel; 5. Extrusion flow channel; 6. Molding outlet; 7. Inner guide surface; 8. Inner material inlet; 100. Mold body. DETAILED DESCRIPTION

[0023] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0024] Embodiment 1

[0025] Reference Figure 1 and 2 As shown, a double-layer co-extrusion injection mold for an optical cable described in the present invention includes a mold body 100, and the mold body 100 is provided with an inner layer material inlet 8, an outer layer guide groove 1, an injection channel 4, an extrusion flow channel 5 and a molding outlet 6, the inner layer material inlet 8 is arranged on one side of the mold body 100, the molding outlet 6 is arranged on the other side of the mold body 100, and the inner layer material inlet 8 is arranged opposite to the molding outlet 6, the outer layer guide groove 1 is arranged on the outer layer of the mold body 100, and the extrusion flow channel 5 is arranged on the inner layer of the molding outlet 6; the injection channel 4 is arranged in the inner layer of the mold body 100, connecting the outer layer guide groove 1 and the extrusion flow channel 5.

[0026] Preferably, the extrusion flow channel 5 is annular. By adopting an annular extrusion flow channel 5, the depth of the flow channel can be easily controlled during mold design, so that the depth of the extrusion flow channel 5 is appropriate, the amount of outer layer thermoplastic material can be limited, and the thickness of the outer layer material extrusion molding can be controlled to a certain extent, which is effectively combined with auxiliary machine control, more flexible, and can achieve better cost control.

[0027] Preferably, the injection channels 4 include four, which are evenly distributed along the circumference of the extrusion flow channel 5. The injection channels 4 are evenly distributed on the circumference of the extrusion flow channel 5, so that the extrusion flow channel 5 can be filled with the outer layer of hot injection material from four directions, which can effectively ensure the balance of the extrusion pressure.

[0028] Furthermore, an annular buffer space is provided at the injection port of the injection channel 4. The injection port of the injection channel 4 has an appropriately enlarged annular space which can be used as a buffer and is not prone to accumulation of thermoplastic materials.

[0029] In this embodiment, the injection port of the injection channel 4 is gradually reduced from large to small. This design can produce better extrusion pressure on the thermoplastic material, so that the thermoplastic material smoothly enters the interior of the injection channel 4 from the outer guide groove.

[0030] Furthermore, a transition inlet 2 is provided between the outer guide groove 1 and the injection channel 4, and a rounded corner is provided at the transition inlet 2. In this embodiment, the transition inlet 2 adopts a smooth rounded transition, and the rounded corner has a certain inclination angle, which can guide the thermoplastic material to flow toward the injection channel 4.

[0031] In actual use, the size of the injection channel 4 can be customized according to the requirements of different products. The size of the injection channel 4 can be adjusted according to the requirements of different products during mold processing.

[0032] Furthermore, the inner wall of the inner layer material inlet 8 is provided with a guide surface, and the guide surface is tapered. The tapered guide surface facilitates the inner layer thermoplastic material to flow smoothly from the inner layer material inlet 8 into the interior of the mold body 100.

[0033] In this embodiment, the inner wall of the outer guide groove 1 is arc-shaped. The outer guide groove 1 is evenly arranged on the outer layer of the mold body 100. Since the inner wall of the outer guide groove 1 is arc-shaped, the pressure is easier to balance, and the inner wall surface of the outer guide groove 1 is smooth, which makes it easier for the molten thermoplastic molding material to flow.

[0034] Preferably, the molding surface of the molding outlet 6 is in a trumpet shape, which can prevent the molded optical cable from being squeezed during the extension process, thereby affecting the quality of product molding.

[0035] Based on the double-layer co-extrusion injection mold for optical cable processing in this embodiment, it is possible to effectively isolate the two materials in the molten state, achieve the effect of simultaneously covering the optoelectronic unit with the two materials, one inside and one outside, and effectively control the amount of outer thermoplastic material. The use of this mold makes the production speed of optical cables faster, with less equipment investment, less material loss, better cost control, and lower mixing degree of the inner and outer layers of materials. In addition, the corresponding color strips can be produced and processed according to actual needs, with strong controllability.

[0036] Embodiment 2

[0037] The present invention provides an injection molding method, which performs double-layer co-extrusion injection molding on an optical cable based on the basic structure of a double-layer co-extrusion injection mold for an optical cable in Example 1. The specific method is as follows: an inner layer thermoplastic material and an outer layer thermoplastic material are respectively injected into the inner layer material inlet 8 and the outer layer guide groove 1, and the outer layer thermoplastic material passes through the outer layer guide groove 1 and enters the extrusion flow channel 5 in an injection manner, so that the outer layer thermoplastic material is filled in the extrusion flow channel 5, and the extrusion flow channel 5 covers the outer layer thermoplastic material on the surface of the preliminarily formed inner layer thermoplastic material, thereby realizing the integrated molding of the two thermoplastic materials, and finally the optical cable is taken out from the molding outlet 6.

[0038] The present invention adopts a smooth arc-shaped guide groove design on the outer layer of the mold body 100, which can prevent the inner and outer thermoplastic materials from mixing at the tail end of the mold body 100100, and enable the outer thermoplastic material in a molten state to flow into the injection channel 4 better, and the multiple injection ports evenly arranged in the injection channel 4 can effectively ensure the balance of the extrusion pressure. In specific use, the inner layer thermoplastic material is injected into the inner layer material inlet 8; when the outer layer thermoplastic material enters the outer layer guide groove 1, it enters the extrusion flow channel 5 by injection, so that the outer layer thermoplastic material is extruded on the surface of the inner layer thermoplastic material, realizing the integrated molding of the two thermoplastic materials, achieving the effective isolation of the two materials in a molten state, and achieving the effect of the two materials, one inside and one outside, covering the optoelectronic unit at the same time.

[0039] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A double-layer co-extrusion injection mold for optical cable, Features: The invention comprises a mould body, on which an inner layer material inlet, an outer layer guide groove, an injection channel, an extrusion flow channel and a forming outlet are provided. The inner layer material inlet is arranged on one side of the mould body, the forming outlet is arranged on the other side of the mould body, and the inner layer material inlet is arranged opposite to the forming outlet. The outer layer guide groove is arranged on the outer layer of the mould body, and the extrusion flow channel is arranged on the inner layer of the forming outlet; the injection channel is arranged on the inner layer of the mould body to connect the outer layer guide groove and the extrusion flow channel.

2. A double-layer co-extrusion injection mold for optical cable according to claim 1, Features: The extrusion flow channel is annular.

3. A double-layer co-extrusion injection mold for optical cable according to claim 2, Features: The injection channels include at least four and are evenly distributed along the circumferential direction of the extrusion flow channel.

4. A double-layer co-extrusion injection mold for optical cable according to claim 1, Features: An annular buffer space is provided at the injection port of the injection channel.

5. A double-layer co-extrusion injection mold for optical cable according to claim 4, Features: The injection port of the injection channel is gradually reduced from large to small.

6. A double-layer co-extrusion injection mold for optical cable according to claim 1, Features: A transition inlet is provided between the outer guide groove and the injection channel, and a rounded corner is provided at the transition inlet.

7. A double-layer co-extrusion injection mold for optical cable according to claim 1, Features: The inner wall of the inner layer material inlet is provided with a guide surface, and the guide surface is tapered.

8. A double-layer co-extrusion injection mold for optical cable according to claim 1, It is characterized in that: It is characterized in that: The inner wall of the outer guide groove is arc-shaped.

9. A double-layer co-extrusion injection mold for optical cable according to claim 1, It is characterized in that: It is characterized in that: The size of the injection channel can be customized according to different product requirements.

10. An injection molding method, implemented by using the double-layer co-extrusion injection molding die for optical cables according to any one of claims 1 to 9, Features: The injection molding method is specifically as follows: the inner layer thermoplastic material and the outer layer thermoplastic material are respectively injected into the inner layer material inlet and the outer layer guide groove, the outer layer thermoplastic material enters the extrusion flow channel through the outer layer guide groove in an injection manner, the outer layer thermoplastic material is filled in the extrusion flow channel, and the extrusion flow channel covers the outer layer thermoplastic material on the surface of the preliminarily formed inner layer thermoplastic material to achieve integrated molding of the two thermoplastic materials, and finally the optical cable is taken out from the molding outlet.

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