Shielded control cable and its manufacturing method

Abstract

The present invention relates to the technical field of wires and cables, and in particular to a shielded control cable, comprising a support bar, a plurality of twisted cores, a shielding layer and an outer insulating layer, wherein the twisted cores comprise convex portions and concave portions spaced apart along the length direction, the convex portions and concave portions of two adjacent twisted cores being staggered, and the twisting direction of more than half of the cores being opposite to the twisting direction of the twisted cores on the outside of the support bar; by axially displacing the plurality of twisted cores in the cable by half a twisting pitch, deformation space required for bending is provided, and the twisting direction of the plurality of twisted cores themselves is opposite to the twisting on the outside of the support bar, so that the cable as a whole has better flexibility and a stable torsional bending state, and the cable has a longer service life in situations where it is frequently bent.

Description

Technical Field

[0001] The present invention relates to the technical field of wire and cable, and particularly to a shielded control cable and a preparation method thereof. Background Art

[0002] A signal cable, also known as a shielded control cable, is a tool and medium for signal transmission. To avoid signal interference, there is a shielding layer outside the signal cable, that is, a shielding layer wrapped around the conductor, which plays a role in resisting electromagnetic radiation and influence in the use environment. For example, the vehicle-grade weak-current shielded control cable widely used in new energy vehicles transmits digital signals and control signals. After being connected to a controller and an actuator through an interface, it is fixed to an appropriate position through a wire harness fixer or a restraint mechanism.

[0003] For example, the signal shielded control cable used for connecting the vehicle body and the wheels of a vehicle will vibrate or deflect as the chassis system moves up and down during vehicle driving. Since the existing signal cables are basically formed by twisting multiple pairs of twisted wires, and in order to make the cable more compact, the twisted wires are wound tightly together, resulting in unstable signal transmission or fatigue breakage of the wire cores. Summary of the Invention

[0004] According to the first aspect of the object of the present invention, a shielded control cable is provided, including:

[0005] A support bar disposed in the cable core;

[0006] A plurality of pairs of twisted wire cores twisted outside the support bar, and each pair of twisted wire cores includes two groups of twisted wire cores;

[0007] A shielding layer wrapped around the outside of the plurality of pairs of twisted wire cores;

[0008] An outer insulating layer extruded outside the shielding layer;

[0009] Wherein, the pair of twisted wire cores includes protrusions and recesses distributed at intervals along the length direction, the protrusions and recesses of adjacent two pairs of twisted wire cores are partially staggered, and the twisting direction of more than half of the wire cores is opposite to the twisting direction of the pair of twisted wire cores outside the support bar.

[0010] Preferably, 3 to 6 pairs of twisted wire cores are twisted outside the support bar.

[0011] Preferably, the cross-section of the support bar is set to be circular or regular polygon.

[0012] Preferably, a cavity distributed along the axial direction is provided at the axis center of the support bar.

[0013] Preferably, the diameter of the support bar is less than or equal to the diameter of the pair of twisted wire cores.

[0014] Preferably, the cross-sectional area of the cavity is 1 / 3 to 2 / 3 of the cross-sectional area of the support bar.

[0015] Preferably, it is defined that the twisting direction of the twisted pair wire core on the outside of the support bar is to the right, and 2 to 5 of the twisting directions of the wire cores are to the left.

[0016] Preferably, the shielding layer is formed by winding conductive cloth or copper foil.

[0017] Preferably, the support bar includes a polyurethane elastic bar.

[0018] Preferably, the wire core includes a conductor and an inner insulating layer coated on the outside of the conductor.

[0019] According to the second aspect of the object of the present invention, a manufacturing method of a shielded control cable is proposed, including the following steps:

[0020] Step 1, manufacturing the support bar: using an extruder to extrude a polyurethane bar to form the support bar;

[0021] Among them, the polyurethane bar is extruded into a solid bar or a hollow bar, and the cross-section of the polyurethane bar is extruded into a circular shape or a regular polygon;

[0022] Step 2, manufacturing the twisted pair wire core:

[0023] 2.1), manufacturing the wire core: using a stranding machine to strand multiple strands of oxygen-free fine copper wires to form conductor wires, and extruding an inner insulating layer of polyethylene material on the outside of the conductor wires to form the wire core;

[0024] 2.2), twisting a pair of the wire cores in a twisted pair manner to form a twisted pair wire core;

[0025] Step 3, stranding the twisted wire core and the support bar: selecting M twisted pair wire cores according to requirements, and stranding the M twisted pair wire cores on the outside of the support bar;

[0026] Among them, two adjacent twisted pair wire cores are distributed in a manner of staggering half a twist pitch axially, and more than M / 2 of the wire cores are stranded in a direction opposite to the stranding direction of the twisted pair wire core on the outside of the support bar;

[0027] Step 4, manufacturing the shielding layer: selecting conductive cloth or copper foil to wrap around the outside of the twisted pair wire core to form the shielding layer;

[0028] Step 5, manufacturing the outer insulating layer: using an extruder to extrude polyethylene material to wrap around the outside of the shielding layer to form the outer insulating layer.

[0029] As can be seen from the above technical solution of the present invention, by offsetting multiple twisted pair cores in the cable axially by half a twist pitch, the deformation space required for bending is provided, and the twisting direction of each twisted pair core itself is opposite to the twisting outside the support strip, so that the overall cable has better flexibility and a stable torsional bending state, enabling the cable to have a longer service life in occasions such as frequent bending. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in each figure may be represented by the same reference numeral. For clarity, not every component is labeled in each figure. Now, embodiments of various aspects of the present invention will be described by way of example and with reference to the drawings, wherein:

[0031] Figure 1 is a schematic cross-sectional structure diagram of the shielded control cable shown in an embodiment of the present invention;

[0032] Figure 2 is a schematic hierarchical structure diagram of the shielded control cable shown in an embodiment of the present invention;

[0033] Figure 3 is a schematic cross-sectional structure diagram of another embodiment of the shielded control cable shown in an embodiment of the present invention;

[0034] Figure 4 is a schematic diagram of the active state of the core in the shielded control cable shown in an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] In order to better understand the technical content of the present invention, specific embodiments are given below in conjunction with the accompanying drawings for illustration.

[0036]

Shielded Control Cable

[0037] Combined with Figure 1 As shown, the shielded control cable according to the embodiment of the first aspect of the present invention aims to increase the flexibility of the cable body under the condition of the same wire diameter, making it more suitable for occasions that require frequent bending, so as to improve the service life of the signal cable.

[0038] As an optional embodiment, the cable mainly includes a support strip 1, twisted pair cores 2, a shielding layer 3, and an outer insulating layer 4.

[0039] Among them, the support strip 1 is arranged at the position of the cable core, and multiple twisted pair cores 2 are twisted outside the support strip 1.

[0040] Each twisted pair core 2 includes two twisted cores 21, and the core 21 includes conductor wires and an inner insulating layer coated on the outside of the conductor, which is used to transmit electrical signals.

[0041] The shielding layer 3 is wound around the outside of a plurality of twisted pair cores 2, providing an electromagnetic shielding effect for the inner twisted pair cores 2 and reducing signal interference.

[0042] The outer insulating layer 4 is extruded with polyethylene material on the outside of the shielding layer 3, playing an insulating and protective role.

[0043] In an alternative embodiment, 3 to 6 twisted pair cores 2 are stranded on the outside of the support strip 1, making the diameter of the support strip 1 less than or equal to the diameter of the twisted pair core 2. When the number of twisted pair cores 2 is three groups, the diameter of the support strip 1 is relatively the smallest, approximately 1 / 7 of the diameter of the circle where the twisted pair cores 2 are located, enabling the three groups of twisted pair cores 2 to be exactly stranded on the outside of the support strip 1 and minimizing the outer diameter of the cable body as much as possible. When the number of twisted pair cores 2 is six groups, the diameter of the support strip 1 is relatively the largest, approximately equal to the diameter of the circle where the twisted pair cores 2 are located.

[0044] Support strip

[0045] Furthermore, in order to make the support strip 1 have high elasticity and flexibility, a cavity 101 distributed along the axial direction is provided at the axis of the support strip 1, and the cross-sectional area of the cavity 101 is 1 / 3 to 2 / 3 of the cross-sectional area of the support strip 1.

[0046] As an alternative embodiment, the support strip 1 is made of a polyurethane elastic strip, making the cable core have high supportability and bending space, providing a buffer space for the high-frequency bending of the cable.

[0047] In an alternative embodiment, as shown in Figure 3 the cross-section of the support strip 1 is set to be circular or regular polygon, which can be selected according to the number and requirements of the twisted pair cores 2. For example, when setting three groups of twisted pair cores 2, a regular triangle or a circle can be selected, and when setting six groups of twisted pair cores 2, a regular hexagon or a circle can be selected.

[0048] Twisted pair core

[0049] As shown in Figure 2 and Figure 4 the twisted pair core 2 includes convex portions 201 and concave portions 202 that are spaced apart along the length direction, and the convex portions 201 and concave portions 202 of adjacent two twisted pair cores 2 are partially staggered.

[0050] In an alternative embodiment, since the convex portions 201 and concave portions 202 of the twisted pair core 2 are partially staggered, when the convex portion 201 of the twisted pair core 2 contacts the support strip 1, in the same cross-section, the concave portions 202 of the two adjacent twisted pair cores 2 on both sides are in a suspended state, and the same distribution is also in the radial direction. When the cable is bent, the suspended gap between the concave portion 202 and the support strip 1 will provide space for deformation, making the whole cable easier to bend and preventing the wire core 21 from being pulled and broken due to fatigue.

[0051] In an alternative embodiment, the stranding direction of more than half of the cores 21 is opposite to the stranding direction of the twisted pair cores 2 outside the support bar 1. That is, when six groups of twisted pair cores 2 are stranded outside the support bar 1, and the stranding direction of the twisted pair cores 2 outside the support bar 1 is defined as right, then the stranding directions of 2 to 5 cores 21 are left.

[0052] In this way, when the cable undergoes torsion in the same direction as the twisted pair cores 2, 2 to 5 cores 21 will be in a relaxed state and will not all be tightened. When the cable undergoes torsion in the opposite direction to the twisted pair cores 2, 2 to 5 cores 21 will be in a tightened state and will not all be relaxed. This can inhibit the bad situation that the whole cable is difficult to bend in a specific direction, making the whole cable more stable under torsion.

[0053] Shielding layer

[0054] In an alternative embodiment, the shielding layer 3 is formed by winding a conductive cloth or copper foil. The conductive cloth is based on a polyester fiber cloth and is subjected to a pre-treatment and then electroplated with a metal coating to make it have metal characteristics and become a conductive fiber cloth, which has relatively better flexibility.

[0055] In this way, by arranging the twisted pair cores 2 with an axial offset distribution, the cable has a deformation space in the bent state, making it easier to bend and not easily break. At the same time, since the stranding directions of the cores 21 in the twisted pair cores 2 are different axially, it can inhibit the bad situation that the whole cable is difficult to bend in a specific direction, making the whole cable more stable under torsion.

[0056]

Manufacturing method of shielded control cable

[0057] The second aspect of the present invention proposes a manufacturing method of a shielded control cable, including the following steps:

[0058] Step 1, manufacturing the support bar 1: Using an extruder to extrude a solid polyurethane bar with a circular cross-section to form the support bar 1. The polyurethane material has good elasticity, enabling the manufactured support bar 1 to have good bending resistance.

[0059] Among them, in order to enable the support bar 1 to have a contractible deformation space under the condition of bending resistance, the polyurethane bar is extruded into a hollow bar. And in order to make the position of the twisted pair cores 2 stranded on the circumferential side of the support bar 1 more stable, the cross-section of the polyurethane bar is extruded into a regular polygon.

[0060] Step 2, manufacturing the twisted pair cores 2:

[0061] 2.1. Manufacturing the core 21: Stranding multiple strands of fine oxygen-free copper wires using a stranding machine to form conductor wires. The oxygen-free copper wires have electrical conductivity, and the conductor formed after stranding multiple strands is softer and easier to bend. An inner insulating layer made of polyethylene material is extruded around the conductor wires to form the core 21.

[0062] 2.2. Twisting a pair of cores 21 in a twisted pair manner to form a twisted pair core 2.

[0063] Step 3. Stranding the twisted pair core 2 with the support bar 1: Select M twisted pair cores 2 according to requirements and strand the M twisted pair cores 2 outside the support bar 1.

[0064] Among them, two adjacent twisted pair cores 2 are distributed in a manner that is axially offset by half a twist pitch, and the stranding directions of more than M / 2 number of core wires 21 are opposite to the stranding direction of the twisted pair core 2 outside the support bar 1.

[0065] In this way, when the convex part 201 of the twisted pair core 2 contacts the support bar 1, in the same cross-section, the concave parts 202 of the twisted pair cores 2 on both sides are in a suspended state, and the same distribution is also along the radial direction. When the cable is bent, the suspended gap between the concave part 202 and the support bar 1 will provide space for deformation, making the overall cable easier to bend and preventing the core wire 21 part from being pulled and broken due to fatigue.

[0066] Step 4. Manufacturing the shielding layer 3: Selecting conductive cloth or copper foil to wrap around the outside of the twisted pair core 2 to form the shielding layer 3. Among them, the conductive cloth is based on a polyester fiber cloth, and after pre-treatment, an electroplated metal coating is applied to make it have metal characteristics and become a conductive fiber cloth, which has relatively better flexibility.

[0067] Step 5. Manufacturing the outer insulating layer 4: Using an extruder to extrude polyethylene material to cover the outside of the shielding layer 3 to form the outer insulating layer.

[0068] Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Those with ordinary knowledge in the technical field to which the present invention belongs can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to what is defined by the claims.

Claims

1. A shielded control cable, characterized in that, it comprises: a support strip (1), arranged in the cable core; a plurality of twisted pair cores (2), twisted outside the support strip (1), and each of the twisted pair cores (2) comprises two groups of cores (21) that are twisted; a shielding layer (3), wrapped around the outside of the plurality of twisted pair cores (2); an outer insulating layer (4), extruded outside the shielding layer (3); wherein, the twisted pair core (2) comprises protrusions (201) and recesses (202) that are distributed at intervals along the length direction, the protrusions (201) and recesses (202) of adjacent two twisted pair cores (2) are partially staggered, and more than half of the cores (21) have a twisting direction opposite to the twisting direction of the twisted pair core (2) outside the support strip (1), and the core (21) comprises a conductor and an inner insulating layer coated on the outside of the conductor; a cavity (101) distributed along the axial direction is provided at the axis center of the support strip (1).

2. The shielded control cable according to claim 1, characterized in that, 3 to 6 of the twisted pair cores (2) are twisted outside the support strip (1).

3. The shielded control cable according to claim 1, characterized in that, the cross-section of the support strip (1) is set to be circular or regular polygon.

4. The shielded control cable according to claim 1, characterized in that, the diameter of the support strip (1) is less than or equal to the diameter of the twisted pair core (2).

5. The shielded control cable according to claim 1, characterized in that, the cross-sectional area of the cavity (101) is 1 / 3 to 2 / 3 of the cross-sectional area of the support strip (1).

6. The shielded control cable according to claim 2, characterized in that, defining the twisting direction of the twisted pair core (2) outside the support strip (1) to be right, and setting the twisting directions of 2 to 5 of the cores (21) to be left.

7. The shielded control cable according to claim 1, characterized in that, the shielding layer (3) is formed by wrapping conductive cloth or copper foil.

8. The shielded control cable according to claim 1, characterized in that, the support strip (1) comprises a polyurethane elastic strip.

9. A manufacturing method of a shielded control cable according to any one of claims 1-8, characterized in that, it comprises the following steps: Step 1, manufacturing the support strip (1): using an extruder to extrude a polyurethane strip to form the support strip (1); wherein, the polyurethane strip is extruded into a solid strip or a hollow strip, and the cross-section of the polyurethane strip is extruded into a circular or regular polygon; Step 2, manufacturing the twisted pair core (2): 2.1), manufacturing the core (21): using a stranding machine to strand a plurality of strands of oxygen-free fine copper wires to form a conductor wire, and extruding an inner insulating layer of polyethylene material on the outside of the conductor wire to form the core (21); 2.2), stranding a pair of the cores (21) in a twisted manner to form the twisted pair core (2); Step 3, stranding the twisted pair core (2) and the support strip (1): selecting M of the twisted pair cores (2) according to requirements, and stranding the M twisted pair cores (2) outside the support strip (1); Among them, two adjacent pairs of twisted cores (2) are distributed in a manner that they are axially offset by half a twist pitch, and the twisting directions of more than M / 2 number of the cores (21) are opposite to the twisting direction of the pairs of twisted cores (2) outside the support strip (1); Step 4, manufacturing the shielding layer (3): Select conductive cloth or copper foil and wrap it around the outside of the pairs of twisted cores (2) to form the shielding layer (3); Step 5, manufacturing the outer insulating layer (4): Use an extruder to extrude polyethylene material to coat the outside of the shielding layer (3) to form the outer insulating layer (4).

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