Bending-resistant flexible cable

Abstract

The utility model belongs to the technical field of cable manufacturing, and discloses a bending-resistant flexible cable, which comprises a plurality of wire cores, an elastic filler, a wrapping layer, an inner lining layer and an outer protective layer, the plurality of wire cores are mutually twisted to form an elliptical cable core, the wrapping layer is wound on the periphery of the elliptical cable core, the elastic filler is filled in a gap between the wrapping layer and the elliptical cable core, and the inner lining layer is arranged on the outer protective layer. The wire core comprises a conductor and an insulating layer, the insulating layer comprises an ethylene-propylene rubber insulating inner layer and a polyolefin elastomer outer layer, the periphery of the wrapping layer is coated with the lining layer, and the periphery of the lining layer is coated with the outer protective layer. The bending-resistant flexible cable provided by the utility model can solve the problems that when an existing cable is bent for a long time or repeatedly bent, a gap is easy to generate between the conductor and the insulating layer, partial discharge or insulation breakdown phenomena are easy to occur in the use process of the cable, the use safety is low, the stress of the insulating layer and the outer protective layer at the bending part of the cable is large, and the service life is long. And the outer protective layer and the insulating layer are easy to crack, so that the service life of the cable is influenced.

Description

Technical Field

[0001] This utility model relates to the field of cable manufacturing technology, and in particular to a flexible cable that is resistant to bending. Background Technology

[0002] A cable is a device for transmitting electrical energy or signals. It is typically composed of several or groups of conductors twisted together to form a core, with the conductors insulated from each other. The entire core is covered with an outer sheath material to protect it. Cables are used in various applications, such as ships, nuclear power plants, and mines.

[0003] Most existing cables are laid in fixed locations, and the bending resistance of commercially available cables is relatively poor. If cables are used under conditions of long-term bending or repeated bending, gaps can easily appear between the conductor and insulation layer during the bending process. This can lead to partial discharge or insulation breakdown during use, affecting the safety of the cable. Furthermore, long-term or repeated bending puts greater stress on the insulation and outer sheath at the bending points, making them prone to cracking and reducing the cable's lifespan.

[0004] Therefore, there is an urgent need for a flexible cable that is resistant to bending to solve the above-mentioned technical problems. Utility Model Content

[0005] The purpose of this invention is to provide a flexible cable that is resistant to bending. This invention addresses the problem that existing cables are prone to gaps between the conductor and insulation layer when subjected to long-term or repeated bending, which can lead to partial discharge or insulation breakdown during use, resulting in low safety. Additionally, the insulation and outer sheath are subjected to high stress at the bending points, making them prone to cracking and affecting the cable's service life.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A bend-resistant flexible cable, comprising:

[0008] The cable consists of multiple conductors, an elastic filler, and a wrapping layer. The conductors are twisted together to form an elliptical cable core, and the wrapping layer is wound around the outer periphery of the elliptical cable core. The elastic filler fills the gap between the wrapping layer and the elliptical cable core. Each conductor includes a conductor and an insulation layer, and the insulation layer includes an inner ethylene propylene rubber insulation layer and an outer polyolefin elastomer layer.

[0009] An inner liner layer that covers the outer periphery of the wrapping layer;

[0010] An outer protective layer, which covers the outer periphery of the inner liner.

[0011] As a preferred technical solution for the bend-resistant flexible cable, the bend-resistant flexible cable further includes a metal braided layer, which is located between the wrapping layer and the inner lining layer.

[0012] As a preferred technical solution for bend-resistant flexible cables, the braiding angle of the metal braid layer is 45° to 60°.

[0013] As a preferred technical solution for bend-resistant flexible cables, the metal braided layer is formed by multiple braided wires, the diameter of which is 0.2mm to 0.4mm.

[0014] As a preferred technical solution for bend-resistant flexible cables, the outer sheath includes a polyimide inner layer and an EVA protective outer layer, wherein the EVA protective outer layer is extruded and wrapped around the outer periphery of the polyimide inner layer.

[0015] As a preferred technical solution for bend-resistant flexible cables, the polyimide inner layer and the EVA protective outer layer are integrally formed by double-layer co-extrusion.

[0016] As a preferred technical solution for bend-resistant flexible cables, the conductor is formed by stranding multiple tinned copper wires, and the stranding diameter ratio of the multiple tinned copper wires is 12 to 14 times.

[0017] As a preferred technical solution for bend-resistant flexible cables, the ethylene propylene rubber insulating inner layer and the polyolefin elastomer outer layer are integrally formed by double-layer co-extrusion.

[0018] As a preferred technical solution for bend-resistant flexible cables, the elastic filler is made of cross-linked fluororubber.

[0019] As a preferred technical solution for bend-resistant flexible cables, the inner liner is made of EVA.

[0020] Compared with the prior art, the bending-resistant flexible cable provided by this utility model has the following technical advantages:

[0021] 1. By twisting multiple wire cores together to form an elliptical cable core, and simultaneously shaping the elliptical cable core with an inner liner, the cross-sectional shape of the bend-resistant flexible cable can be elliptical. Compared to existing cables with a circular cross-section, the bend-resistant flexible cable can better withstand lateral pressure under bending and compression conditions. Compared to cables with a circular cross-section, it has better resistance to extrusion deformation, reducing the risk of cracking of the outer sheath and insulation layer, and ensuring a certain service life for the bend-resistant flexible cable.

[0022] 2: An elastic filler is filled in the gap between the elliptical cable core and the sheath. Due to the large deformation range of the elastic filler, when the flexible cable is bent, it can make the outer sheath, inner lining, elastic filler and elliptical cable core fit together closely. This ensures that the pressure on the flexible cable under compression is evenly distributed on the outer sheath, inner lining, elastic filler and elliptical cable core, further reducing the risk of cracking of the outer sheath and insulation layer when the flexible cable is bent.

[0023] 3. The insulation layer is designed as a double-layer structure consisting of an inner ethylene propylene rubber insulation layer and an outer polyolefin elastomer layer. The inner ethylene propylene rubber insulation layer ensures the insulation performance of the insulation layer. Due to the high elasticity and high degree of deformation of the outer polyolefin elastomer layer, when the conductor deforms due to bending, the outer polyolefin elastomer layer ensures that the insulation layer is always in close contact with the conductor, avoiding gaps between the conductor and the insulation layer. This prevents partial discharge or insulation breakdown during use of the flexible cable, thus ensuring the safety of the flexible cable. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the bend-resistant flexible cable provided by this utility model.

[0025] In the picture:

[0026] 11. Core; 111. Conductor; 112. Insulation layer; 1121. Inner layer of ethylene propylene rubber insulation; 1122. Outer layer of polyolefin elastomer;

[0027] 2. Elastic filler; 3. Wrapping layer; 4. Metal braided layer; 5. Inner lining layer;

[0028] 6. Outer protective layer; 61. Polyimide inner layer; 62. EVA protective outer layer. 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, and not the entire structure.

[0030] In the description of this utility model, unless otherwise explicitly 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; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. 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," "lower," "right," 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] like Figure 1 As shown in the illustration, this embodiment provides a bend-resistant flexible cable, including multiple conductors 11, an elastic filler 2, a wrapping layer 3, an inner liner layer 5, and an outer sheath layer 6. The multiple conductors 11 are twisted together to form an elliptical cable core. The wrapping layer 3 is wound around the outer periphery of the elliptical cable core. The wrapping layer 3 prevents the elliptical cable core from loosening, ensuring stable current transmission of the bend-resistant flexible cable. The elastic filler 2 fills the gap between the wrapping layer 3 and the elliptical cable core. The conductor 11 includes a conductor 111 and an insulation layer 112. The insulation layer 112 includes an inner ethylene propylene rubber insulation layer 1121 and an outer polyolefin elastomer outer layer 1122. The inner liner layer 5 covers the outer periphery of the wrapping layer 3. The inner liner layer 5 helps to shape the elliptical cable core, making it compact and reducing the risk of loosening. The outer sheath layer 6 covers the outer periphery of the inner liner layer 5 and is used to protect the bend-resistant flexible cable.

[0034] The bend-resistant flexible cable provided in this embodiment forms an elliptical cable core by twisting multiple cores 11 together. Simultaneously, the inner liner 5 shapes the elliptical cable core, resulting in an elliptical cross-section. Compared to existing cables with circular cross-sections, this elliptical cable can better withstand lateral pressure under bending and compression conditions. Furthermore, its superior resistance to compression deformation compared to circular cross-sections reduces the risk of cracking in the outer sheath 6 and insulation layer 112, thus ensuring a certain service life for the bend-resistant flexible cable. Additionally, an elastic filler 2 is filled into the gap between the elliptical cable core and the wrapping layer 3. Due to the large deformation range of the elastic filler 2, when the bend-resistant flexible cable is bent, it ensures a high degree of adhesion between the outer sheath 6, inner liner 5, elastic filler 2, and elliptical cable core. This allows the pressure exerted on the bend-resistant flexible cable under compression to be evenly distributed across the outer sheath 6, inner liner 5, elastic filler 2, and elliptical cable core, further reducing the risk of cracking in the outer sheath 6 and insulation layer 112 during bending.

[0035] The insulation layer 112 is designed as a double-layer structure consisting of an inner ethylene propylene rubber insulation layer 1121 and an outer polyolefin elastomer layer 1122. The inner ethylene propylene rubber insulation layer 1121 ensures the insulation performance of the insulation layer 112. Due to the high elasticity and high degree of deformation of the outer polyolefin elastomer layer 1122, when the conductor 111 deforms due to bending, the outer polyolefin elastomer layer 1122 ensures that the insulation layer 112 is always in close contact with the conductor 111, avoiding the problem of gaps between the conductor 111 and the insulation layer 112. This avoids partial discharge or insulation breakdown during the use of the bend-resistant flexible cable, thus ensuring the safety of the bend-resistant flexible cable.

[0036] On the other hand, when the conductor 111 carries current, it will expand due to heat. When the conductor 111 expands due to heat, the insulation layer 112 is compressed, and the outer polyolefin elastomer 1122 undergoes elastic deformation. When the temperature of the conductor 111 decreases, the outer polyolefin elastomer returns to its original shape, so that the inner ethylene propylene rubber insulation layer 1121 is tightly attached to the conductor 111. This avoids the problem of the insulation layer 112 not being tightly attached to the conductor 111 after the conductor 111 expands due to heat. This ensures that the insulation layer 112 can always be attached to the conductor 111 regardless of whether the conductor 111 is in an expanded state, thereby improving the safety of the flexible cable.

[0037] In this embodiment, the wrapping layer 3 can be made of non-woven fabric.

[0038] In this embodiment, the elastic filler 2 is made of cross-linked fluororubber. Cross-linked fluororubber not only has elasticity, but also high temperature resistance and corrosion resistance. It can make the flexible cable bendable and further improve the service life of the flexible cable.

[0039] In this embodiment, the bend-resistant flexible cable also includes a metal braided layer 4, which is located between the wrapping layer 3 and the inner liner layer 5. On one hand, the metal braided layer 4 improves the bend-resistant flexible cable's resistance to external electromagnetic interference, enabling more stable current transmission. On the other hand, the shape of the metal braided layer 4 can be braided according to the shape of the elliptical cable core. Thus, the metal braided layer 4 further helps to shape the elliptical cable core, further reducing the risk of the elliptical cable core becoming loose. Furthermore, in actual processing, after the metal braided layer 4 is fitted around the wrapping layer 3, the material of the inner liner layer 5 can be squeezed and wrapped around the outer periphery of the metal braided layer 4. At this time, the metal braided layer 4 and the inner liner layer 5 are bonded together, preventing stress concentration on the metal braided layer 4 when the bend-resistant flexible cable is bent. This further ensures the electromagnetic interference shielding performance of the bend-resistant flexible cable, thereby guaranteeing the reliability of the bend-resistant flexible cable's operation.

[0040] Furthermore, the braiding angle of the metal braid layer 4 is 45° to 60°. This ensures both the shielding effect of the metal braid layer 4 and its flexibility, thereby guaranteeing the flexibility of the bend-resistant flexible cable and further improving its performance. In this embodiment, the metal braid layer 4 is formed by multiple braided filaments, with the diameter of the filaments being 0.2mm to 0.4mm, further enhancing the flexibility of the metal braid layer 4.

[0041] Furthermore, conductor 111 is formed by stranding multiple tinned copper wires, with a stranding pitch ratio of 12 to 14 times. This arrangement not only ensures stable current transmission within conductor 111 but also prevents excessively dense stranding of the tinned copper wires, thus guaranteeing the flexibility of conductor 111 and further enhancing the bending resistance and the number of bends it can withstand. Conductor 111 is either a Category 2 or Category 5 conductor to further improve its flexibility. For Category 2 and Category 5 conductors, refer to the relevant provisions in GB / T3956-2008; details will not be elaborated upon here.

[0042] In this embodiment, the outer sheath 6 comprises a polyimide inner layer 61 and an EVA protective outer layer 62, wherein the EVA material is an ethylene-vinyl acetate copolymer. Polyimide possesses excellent flame retardancy, mechanical properties, radiation resistance, chemical stability, and environmental friendliness, while EVA material exhibits excellent flexibility, elasticity, cushioning, and weather resistance. When the flexible cable is bent, the polyimide inner layer 61 and the EVA protective outer layer 62 provide dual protection, reducing the damage to the outer sheath 6 after prolonged and repeated bending. Simultaneously, this also endows the flexible cable with excellent flame retardancy, compression resistance, weather resistance, and environmental friendliness, further improving the safety and service life of the flexible cable. Furthermore, the polyimide inner layer 61 and the EVA protective outer layer 62 are integrally formed through a double-layer co-extrusion process. This ensures a tight bond between the polyimide inner layer 61 and the EVA protective outer layer 62, preventing moisture ingress and guaranteeing the service life of the outer sheath 6. Simultaneously, the double-layer co-extrusion process further improves the processing efficiency of the outer sheath 6.

[0043] Preferably, the ethylene propylene rubber insulating inner layer 1121 and the polyolefin elastomer outer layer 1122 are integrally formed by double-layer co-extrusion. This ensures that the ethylene propylene rubber insulating inner layer 1121 and the polyolefin elastomer outer layer 1122 are tightly bonded together, preventing moisture from entering the insulating layer 112 and ensuring the service life of the insulating layer 112. At the same time, the double-layer co-extrusion process can further improve the processing efficiency of the insulating layer 112.

[0044] Furthermore, the present invention will be described in conjunction with specific embodiments.

[0045] Example 1

[0046] The bend-resistant flexible cable comprises four cores 11, which are twisted together to form an elliptical cable core. The conductors 111 within the cores 11 are made of 0.8mm tinned copper wire with a pitch ratio of 13. The insulation layer 112 consists of an ethylene propylene rubber inner layer 1121 with a thickness of 1.2mm, a polyolefin elastomer outer layer 1122 with a thickness of 1.5mm, a metal braided layer 4 made of tinned copper wire with a single filament diameter of 0.25mm and a braiding angle of 50°, an inner lining layer 5 with a thickness of 1mm, an outer sheath 6 with a draw ratio of 1.03, a polyimide inner layer 61 with a thickness of 0.5mm, and an EVA protective outer layer 62 with a thickness of 1mm.

[0047] Example 2

[0048] The bend-resistant flexible cable comprises four cores 11, which are twisted together to form an elliptical cable core. The conductors 111 within the cores 11 are made of 1.2mm tinned copper wire with a pitch ratio of 14. The insulation layer 112 consists of an ethylene propylene rubber inner layer 1121 with a thickness of 1.8mm, a polyolefin elastomer outer layer 1122 with a thickness of 2mm, a metal braided layer 4 made of tinned copper wire with a single filament diameter of 0.3mm and a braiding angle of 55°, an inner lining layer 5 with a thickness of 1.2mm, an outer sheath 6 with a draw ratio of 1.02, a polyimide inner layer 61 with a thickness of 0.6mm, and an EVA protective outer layer 62 with a thickness of 1.2mm.

[0049] Example 3

[0050] The bend-resistant flexible cable comprises four cores 11, which are twisted together to form an elliptical cable core. The conductors 111 within the cores 11 are made of 1.5mm tinned copper wire with a pitch ratio of 14. The insulation layer 112 consists of an ethylene propylene rubber inner layer 1121 with a thickness of 2.2mm, a polyolefin elastomer outer layer 1122 with a thickness of 2.5mm, a metal braided layer 4 made of tinned copper wire with a single filament diameter of 0.35mm and a braiding angle of 60°, an inner lining layer 5 with a thickness of 1.5mm, an outer sheath 6 with a draw ratio of 1.01, a polyimide inner layer 61 with a thickness of 0.8mm, and an EVA protective outer layer 62 with a thickness of 1.5mm.

[0051] 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 bend-resistant flexible electrical cable, characterized by, include: The cable consists of multiple conductors (11), an elastic filler (2), and a wrapping layer (3). The multiple conductors (11) are twisted together to form an elliptical cable core. The wrapping layer (3) is wound around the outer periphery of the elliptical cable core. The elastic filler (2) fills the gap between the wrapping layer (3) and the elliptical cable core. The conductor (11) includes a conductor (111) and an insulation layer (112). The insulation layer (112) includes an inner ethylene propylene rubber insulation layer (1121) and an outer polyolefin elastomer layer (1122). Inner liner (5), which covers the outer periphery of the wrapping layer (3); Outer protective layer (6) covers the outer periphery of the inner lining layer (5).

2. The bend-resistant flexible cable according to claim 1, characterized in that, The bend-resistant flexible cable also includes a metal braided layer (4), which is located between the wrapping layer (3) and the inner lining layer (5).

3. The bend-insensitive flexible cable of claim 2, wherein, The braiding angle of the metal braided layer (4) is 45° to 60°.

4. The bend-insensitive flexible cable of claim 3, wherein, The metal braided layer (4) is formed by multiple braided wires, the diameter of which is 0.2mm to 0.4mm.

5. The bend-insensitive flexible cable of claim 1, wherein, The outer protective layer (6) includes a polyimide inner layer (61) and an EVA protective outer layer (62), wherein the EVA protective outer layer (62) is extruded and covered around the outer periphery of the polyimide inner layer (61).

6. The bend-insensitive flexible cable of claim 5, wherein, The polyimide inner layer (61) and the EVA protective outer layer (62) are integrally formed by double-layer co-extrusion.

7. The bend-insensitive flexible cable of any of claims 1-6, wherein, The conductor (111) is formed by stranding multiple tin-plated copper wires together, and the stranding diameter ratio of the multiple tin-plated copper wires is 12 to 14 times.

8. The bend-insensitive flexible cable of any of claims 1-6, wherein, The ethylene propylene rubber insulating inner layer (1121) and the polyolefin elastomer outer layer (1122) are integrally formed by double-layer co-extrusion.

9. The bend-insensitive flexible cable of any of claims 1-6, wherein, The elastic filler (2) is made of cross-linked fluororubber.

10. The bend-insensitive flexible cable of any of claims 1-6, wherein, The inner lining layer (5) is made of EVA.

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