Movable leaky coaxial cable and manufacturing method thereof

Abstract

The invention relates to a mobile leaky coaxial cable and a manufacturing method thereof. The cable comprises an inner conductor; the insulating layer covers the outer surface of the inner conductor; the shielding layer covers the outer surface of the insulating layer, the shielding layer adopts a metal strip with a corrugated structure, and four groups of slotted holes are formed in the shielding layer so as to realize leakage of electromagnetic wave signals; wherein each slotted hole is arranged at a wave crest part of the corrugated structure, and the four groups of slotted holes are uniformly distributed along the circumferential direction of the shielding layer and are spaced from each other by 90 degrees; the sheath layer covers the outer surface of the shielding layer; and the flame-retardant ropes are arranged in the sheath layer, and the multiple flame-retardant ropes are distributed on the long diagonals and symmetrically distributed along the two sides of the centers of the long diagonals. According to the invention, rapid laying and rapid recovery can be realized, and wireless signal coverage can be realized without considering the installation direction.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technologies, and particularly to a mobile leaky coaxial cable and a manufacturing method thereof. Background Art

[0002] Traditional leaky coaxial cables are mainly applied to enclosed or semi-enclosed places such as tunnels, mines, subways, basements, etc., for compensating wireless signal blind areas and enhancing wireless communication coverage capabilities.

[0003] Due to the complex usage scenarios of leaky coaxial cables, during the actual laying process of existing leaky coaxial cables, an installation fixture fixing method needs to be adopted. Specifically, before using the leaky coaxial cable, the actual laying route needs to be constructed first. First, leaky coaxial cable fixtures suitable for the scenario need to be designed according to the usage scenario; secondly, holes need to be drilled in the wall or fixed bracket for fixture fixing, and then the fixture is fixed to the wall using expansion bolts, or the bolts and the bracket are fixed together on the existing bracket; finally, the leaky coaxial cable is installed on the fixture, and certain twisting and adjustment need to be made according to the installation direction of the leaky coaxial cable to keep the signal radiation direction of the leaky coaxial cable facing the receiving device.

[0004] However, the structures of existing leaky coaxial cables have the following defects: the installation construction is complex, and in special scenarios, a fixture fixing scheme needs to be designed according to the actual on-site environment to meet the installation of the leaky coaxial cable. The installation of the leaky coaxial cable requires supporting facilities such as fixtures, bolts or brackets. First, the fixture is fixed, and then the leaky coaxial cable is installed; it is inconvenient to recycle the fixture and the leaky coaxial cable after installation, and it is suitable for long-term use in fixed places; the installation of the leaky coaxial cable has a certain directionality, and appropriate adjustment is required during installation; the radiation of the leaky coaxial cable has directionality, and there is no signal when facing away from the radiation direction; in the case of underground or indoor communication in large buildings being damaged during emergency rescue and fire fighting, and there is temporarily no communication infrastructure, traditional wireless communication coverage in this scenario cannot quickly respond for rescue, positioning. Summary of the Invention

[0005] Therefore, the present invention provides a mobile leaky coaxial cable and a manufacturing method thereof, which adopt a non-fixed laying method, can achieve rapid laying and quick recovery, and can achieve wireless signal coverage without considering the installation direction.

[0006] To solve the above technical problems, the present invention provides a mobile leaky coaxial cable, including: Inner conductor; Insulation layer, covering the outer surface of the inner conductor; The shielding layer covers the outer surface of the insulating layer. The shielding layer is made of a metal strip with a corrugated structure, and four groups of slots are provided on the shielding layer to achieve the leakage of electromagnetic wave signals. Among them, each of the slots is provided at the peak of the corrugated structure, and the four groups of slots are evenly distributed along the circumferential direction of the shielding layer and are spaced 90° from each other. The sheath layer covers the outer surface of the shielding layer. Among them, the cross-section of the sheath layer is a rhombus structure and has a long diagonal and a short diagonal. The center line of the included angle formed by two adjacent groups of slots coincides with the long diagonal or the short diagonal. The center of the inner conductor coincides with the center of the rhombus structure. The side of the rhombus structure is adapted to contact the installation plane, and after contacting the installation plane, the proportion of the circumference of the shielding layer covered by the four groups of slots is configured to enable the cable signal coverage angle to be greater than 180°. The flame-retardant rope is arranged inside the sheath layer for achieving flame-retardant physical isolation. Multiple flame-retardant ropes are distributed on the long diagonal and are symmetrically distributed on both sides of the center of the long diagonal.

[0007] In an embodiment of the present invention, the four groups of slots together cover 50% - 90% of the circumference of the shielding layer.

[0008] In an embodiment of the present invention, the inner conductor includes one or more metal conductors and is made of solid, hollow metal materials or composite metal materials.

[0009] In an embodiment of the present invention, the material of the insulating layer includes polyethylene, polyvinyl chloride or polytetrafluoroethylene and is in a solid or foamed structure.

[0010] In an embodiment of the present invention, the sheath layer is made of a low-smoke and halogen-free flame-retardant material.

[0011] In an embodiment of the present invention, the flame-retardant rope is made of a basalt fiber rope.

[0012] In an embodiment of the present invention, the flame-retardant rope includes a small-diameter flame-retardant rope and a large-diameter flame-retardant rope. One small-diameter flame-retardant rope and one large-diameter flame-retardant rope are respectively arranged on both sides of the center of the long diagonal, and the small-diameter flame-retardant rope is located on the side far from the center of the long diagonal.

[0013] The present invention also provides a manufacturing method for a mobile leaky coaxial cable for manufacturing the mobile leaky coaxial cable, including: S1. Stranding one or more metal conductors to obtain an inner conductor; S2. Coating an insulating layer with a solid or foamed structure on the outer surface of the inner conductor by an extrusion process. The material of the insulating layer includes polyethylene, polyvinyl chloride or polytetrafluoroethylene; S3. On the outer surface of the insulating layer, a metal strip is wrapped in a longitudinal wrapping manner, and the overlapping seam of the metal strip is welded. Subsequently, a shielding layer with a corrugated structure having periodic peaks and valleys is formed through a corrugating process; S4. Provide a hollow tubular mold. Four cutting plane grooves that are symmetrically arranged and spaced 90° are provided in the central hole section of the hollow tubular mold; pass the shielding layer through the hollow tubular mold, and the gap between the central hole section of the hollow tubular mold and the shielding layer is 2 - 5 mm; milling cutters are correspondingly arranged at each cutting plane groove; Pass the shielding layer through the hollow tubular mold, pass the milling cutter through the cutting plane groove, and cut the peak parts of the corrugated structure of the shielding layer, thereby machining four groups of slot holes that are evenly distributed along the circumference of the shielding layer and spaced 90° from each other; S5. Provide a sheath extrusion mold. The sheath extrusion mold includes an extrusion die core and an extrusion die sleeve. The extrusion die core includes a conical guiding part and a wire threading part located at one end of the conical guiding part; Among them, the extrusion die sleeve is provided with a die cavity adapted to be in clearance fit with the extrusion die core, and a diamond-shaped hole located on the outer circumference of the wire threading part is provided at the end of the die cavity; The wire threading part includes a shielding layer wire threading hole and flame retardant rope wire threading holes located on both sides of the shielding layer wire threading hole; the shielding layer wire threading hole is adapted for the shielding layer to pass through, and the flame retardant rope wire threading holes are adapted for the flame retardant rope to pass through; the shielding layer wire threading hole is a square hole, and the diagonal of the diamond-shaped hole coincides with the diagonal of the shielding layer wire threading hole; Adjust the long diagonal of the diamond-shaped hole to be in a horizontal state, and adjust the shielding layer with the slot holes so that the center line of the included angle formed by two adjacent groups of slot holes is kept coincident with the long diagonal or the short diagonal of the diamond-shaped hole, and then send it into the shielding layer wire threading hole. The gap between the shielding layer wire threading hole and the shielding layer is 1 - 5 mm; S6. Install the sheath extrusion mold on the head of the extruder. The sheath material is extruded from the head of the extruder, flows through the conical guiding part, and is extruded from the gap between the extrusion die core and the extrusion die sleeve. At the same time, during the sheath extrusion process, a flame retardant rope made of basalt fiber material is introduced into the flame retardant rope wire threading hole, and the sheath material wraps the shielding layer and the flame retardant rope, and finally forms a sheath layer; S7. After the sheath layer is wrapped, it is cooled and shaped to obtain a finished product of a mobile leaky coaxial cable.

[0014] In one embodiment of the present invention, the milling cutter is driven by a servo motor, with a single - cutter power of 50 - 500 W, a rotational speed of 50 - 500 revolutions per minute, and a tool stepping speed of 0.1 - 5 mm / s. All the milling cutters achieve synchronous start - stop and consistent rotational speed through the same servo control system, ensuring the dimensional consistency of the slot - hole processing.

[0015] In one embodiment of the present invention, the size of each cutting - plane groove is: length 50 mm, width 10 - 40 mm; the size of the slot - hole is: length 10 - 30 mm, width 3 - 15 mm.

[0016] The above - mentioned technical solution of the present invention has the following advantages compared with the prior art: A mobile leaky coaxial cable and its manufacturing method according to the present invention. The mobile leaky coaxial cable of the present invention is for non - fixed laying. It can be laid by simply placing it on the ground along the line, and can be quickly retrieved after use. It is convenient to use and can be reused. The mobile leaky coaxial cable of the present invention can be quickly laid without fixed installation. The mobile leaky coaxial cable of the present invention does not require the use of accessories, saving construction costs. The mobile leaky coaxial cable of the present invention has a diamond - shaped structure. Only two sides of the diamond - shaped structure will contact the ground, and both can achieve wireless signal coverage without considering the installation direction. The mobile leaky coaxial cable of the present invention has a wireless electromagnetic wave signal coverage range of more than 180°, and has a wider coverage range compared with traditional leaky cables. The mobile leaky coaxial cable of the present invention has a flame - retardant physical isolation structure, which can achieve self - protection of the leaky cable, thus ensuring the wireless communication requirements during a fire. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to make the content of the present invention easier to be clearly understood, the following further details the present invention according to specific embodiments of the present invention in combination with the accompanying drawings.

[0018] Figure 1 It is a cross - sectional view of the mobile leaky coaxial cable in Embodiment 1 of the present invention placed on the ground.

[0019] Figure 2 It is a cross - sectional view of the mobile leaky coaxial cable in Embodiment 1 of the present invention.

[0020] Figure 3 It is a schematic structural diagram of the hollow tubular mold in Embodiment 2 of the present invention.

[0021] Figure 4 It is a schematic diagram of the use state of the hollow tubular mold in Embodiment 2 of the present invention.

[0022] Figure 5 It is a schematic structural diagram of one side of the extrusion die core in Embodiment 2 of the present invention.

[0023] Figure 6 It is a schematic structural diagram of the other side of the extrusion die core in Embodiment 2 of the present invention.

[0024] Figure 7 It is a schematic structural diagram of one side of the extrusion die sleeve in Embodiment 2 of the present invention.

[0025] Figure 8 It is a schematic structural diagram of the other side of the extrusion die sleeve in Embodiment 2 of the present invention.

[0026] Explanation of the reference numerals in the accompanying drawings of the specification: 1. Inner conductor; 2. Insulating layer; 3. Shielding layer; 31. Slot hole; 4. Sheath layer; 5. Flame-retardant rope; 5a. Small-diameter flame-retardant rope; 5b. Large-diameter flame-retardant rope; 6. Extrusion die core; 61. Conical flow guiding part; 62. Wire threading part; 621. Shielding layer wire threading hole; 622. Flame-retardant rope wire threading hole; 7. Extrusion die sleeve; 71. Die cavity; 72. Diamond hole; 8. Hollow tubular mold; 81. Cutting plane groove; 82. Milling cutter. Detailed implementation manners

[0027] The present invention will be 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 be able to implement it, but the specific embodiments cited are not intended to limit the present invention.

[0028] In the present invention, when directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical solution of the present invention, rather than indicating or implying that the technical features referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0029] In the present invention, the meaning of "several" is one or more, the meaning of "multiple" is two or more, and understandings such as "greater than", "less than", "exceeding" do not include the present number; understandings such as "above", "below", "within" include the present number. In the description of the present invention, if "first" and "second" are described, they are only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0030] In the present invention, unless otherwise clearly defined, terms such as "arranged", "installed", "connected", etc. should be understood in a broad sense. For example, it can be directly connected, or indirectly connected through an intermediate medium; it can be fixedly connected, or detachably connected, or integrally formed; it can be mechanically connected, or electrically connected or capable of communicating with each other; it can be the communication inside two components or the interaction relationship between two components. Those skilled in the art can reasonably determine the specific meaning of the above terms in the present invention in combination with the specific content of the technical solution.

[0031] Embodiment 1 Referring to Figure 1 、 Figure 2 As shown, a mobile leaky coaxial cable of this embodiment includes: Inner conductor 1; Insulating layer 2, covering the outer surface of the inner conductor 1; used to provide electrical insulation and structural support; Shielding layer 3, covering the outer surface of the insulating layer 2. The shielding layer 3 is made of a metal strip with a corrugated structure. Four groups of slot holes 31 are provided on the shielding layer 3 to achieve the leakage of electromagnetic wave signals and realize wireless communication. Among them, each of the slot holes 31 is arranged at the peak position of the corrugated structure. The four groups of slot holes 31 are evenly distributed (concentric) along the circumferential direction of the shielding layer 3 and are spaced 90° from each other. By adopting the shielding layer 3 with a corrugated structure, the tensile and bending properties at the use site can be improved; Sheath layer 4, covering the outer surface of the shielding layer 3. Among them, the cross-section of the sheath layer 4 is a rhombus structure and has a long diagonal ( Figure 2 b in) and a short diagonal ( Figure 2 a in). The center line ( Figure 2 c in) of the included angle formed by two adjacent groups of slot holes 31 coincides with the long diagonal or the short diagonal; the center of the inner conductor 1 coincides with the center of the rhombus structure; the sides of the rhombus structure are adapted to contact the installation plane (such as the ground, etc.), and after contacting the installation plane, the proportion of the circumference of the shielding layer 3 covered by the four groups of slot holes 31 is configured to be able to achieve a cable signal coverage angle greater than 180°; Flame-retardant rope 5, arranged inside the sheath layer 4, used to achieve flame-retardant physical isolation and protect the cable; among them, multiple flame-retardant ropes 5 are distributed on the long diagonal and are symmetrically distributed on both sides of the center of the long diagonal.

[0032] By setting the sheath layer 4 with a diamond structure and four groups of slots 31 evenly distributed circumferentially along the shielding layer 3 and spaced 90° from each other, when the leaky coaxial cable is placed on the ground in any direction, the sides of the diamond structure always contact the ground, and there is always a group of two adjacent slots 31 from which the electromagnetic wave signals radiate upward from the ground, ensuring that the cable signal coverage angle is greater than 180°, achieving signal coverage without dead angles in the space above the ground. The cooperation between the sheath layer 4 with a diamond structure and the slots 31 of the shielding layer 3 enables the cable to be laid arbitrarily and signal coverage can be achieved; there is no need to consider the directivity of the leaky cable, saving laying time; the flame-retardant rope 5 achieves flame-retardant physical isolation and protects the cable itself.

[0033] Specifically, the four groups of slots 31 altogether cover 50% - 90% of the circumference of the shielding layer 3. The size of the slots 31 is designed according to the outer diameter of the shielding layer 3. By setting the proportion of 50% - 90%, a signal coverage angle greater than 180° can be achieved.

[0034] In the conventional industry design, the coupled leaky cable has slots on one or two sides, and the electromagnetic wave radiation energy diffuses in a concentric circle manner, with a relatively uniform coverage range. The radiation angle of the coupled leaky cable is usually between ±60° and ±90° (i.e., the omnidirectional coverage angle is 120° - 180°), while in this embodiment, through the slots on four sides, the radiation angle fully meets the omnidirectional 180° coverage.

[0035] It should be noted that the number of slots 31 in each group is one, or multiple slots are distributed at intervals along the cable length direction; the corrugated structure on the shielding layer 3 extends along the length direction.

[0036] It can be understood that when the sheath layer 4 with a diamond structure is placed forward or backward, there is always a group of two adjacent slots 31 on the corrugated shielding layer 3 from which the electromagnetic wave signals can achieve a signal coverage angle greater than 180°.

[0037] When the sheath layer 4 with a diamond structure is laid for the leaky coaxial cable, only two adjacent sides on one side of the long diagonal of the diamond structure will contact the ground. However, no matter which side contacts the ground, two of the four groups of slots 31 can radiate electromagnetic wave signals upward to the ground.

[0038] In addition, even when the leaky coaxial cable is laid in a hurry in a complex environment and has a twist, in this embodiment, the twist length of the leaky coaxial cable is only 3 - 5 times the length of the long diagonal of the diamond structure, and two of the four slots 31 on the corrugated shielding can radiate electromagnetic wave signals upward to the ground.

[0039] Specifically, the ratio of the long diagonal to the short diagonal of the diamond structure is greater than 5:1, ensuring a relatively stable placement on the ground.

[0040] Specifically, the inner conductor 1 includes one or more metal conductors and is made of solid, hollow metal materials or composite metal materials.

[0041] Specifically, the material of the insulating layer 2 includes polyethylene, polyvinyl chloride or polytetrafluoroethylene and is in a solid or foamed structure.

[0042] Specifically, the sheath layer 4 is made of a low-smoke, halogen-free and flame-retardant material.

[0043] Specifically, the flame-retardant rope 5 includes a small-diameter flame-retardant rope 5a and a large-diameter flame-retardant rope 5b. One small-diameter flame-retardant rope 5a and one large-diameter flame-retardant rope 5b are respectively arranged on both sides of the center of the long diagonal, and the small-diameter flame-retardant rope 5a is located on the side far from the center of the long diagonal.

[0044] When one side of the rhombus-shaped sheath layer 4 contacts the ground, when there is a fire source on the ground burning to the mobile leaky coaxial cable, the material of the sheath layer 4 itself has flame retardancy. Even if the fire spreads to the flame-retardant rope 5, the flame-retardant rope 5 has high flame retardancy and can achieve physical isolation. The small-diameter flame-retardant rope 5a is the first line of defense for physical isolation, and the large-diameter flame-retardant rope 5b is the second line of defense.

[0045] In addition, the small-diameter flame-retardant rope 5a is close to the edge of the long diagonal. The leaky coaxial cable has a certain angle of twist at the small-diameter flame-retardant rope 5a, which can reduce the length of the overall rhombus of the mobile leaky coaxial cable during twisting and facilitate the cable winding and unwinding. The flame-retardant rope 5 has a certain flexibility, so it can avoid generating excessive internal stress during the dynamic changes of the cable (such as winding and unwinding, turning, compressing), and improve the structural self-adaptive ability.

[0046] The flame-retardant rope 5 also has a certain tensile property, which can withstand violent pulling in a complex environment and protect the mobile leaky coaxial cable.

[0047] The flame-retardant rope 5 is a basalt fiber rope, and its material is made by high-temperature melting and wire drawing of volcanic rock. The main component is silicate, which is non-combustible and has a fire resistance temperature of 1200 °C. It does not burn or carbonize when encountering fire. It can maintain structural stability at high temperatures, has high fiber strength, can withstand mechanical stress, and has a smooth surface and strong wear resistance.

[0048] Embodiment 2 This embodiment provides a manufacturing method of a mobile leaky coaxial cable for manufacturing the described mobile leaky coaxial cable, including: S1. Stranding one or more metal conductors to obtain the inner conductor 1.

[0049] S2. On the outer surface of the inner conductor 1, an insulating layer 2 in a solid or foamed structure is coated by an extrusion process, and the material of the insulating layer 2 includes polyethylene, polyvinyl chloride or polytetrafluoroethylene.

[0050] S3. On the outer surface of the insulating layer 2, a metal strip is wrapped in a longitudinal wrapping manner, and the overlapping seam of the metal strip is welded. Subsequently, a shielding layer 3 with a corrugated structure having periodic peaks and valleys is formed by a grooving process.

[0051] S4. Referring to Figure 3 As shown, a hollow tubular mold 8 is provided. Four cutting plane grooves 81 that are symmetrically arranged and spaced 90° apart are provided in the central hole section of the hollow tubular mold 8. The shielding layer 3 is passed through the hollow tubular mold 8, and the gap between the central hole section of the hollow tubular mold 8 and the shielding layer 3 is 2 - 5 mm. Milling cutters 82 are correspondingly arranged at each of the cutting plane grooves 81. The size of each cutting plane groove 81 is: length 50 mm, width 10 - 40 mm. Referring to Figure 4 As shown, during cutting, the shielding layer 3 is passed through the hollow tubular mold 8, the milling cutters 82 are passed through the cutting plane grooves 81, and the peak portions of the corrugated structure of the shielding layer 3 are cut, thereby machining out four groups of slot holes 31 that are evenly distributed along the circumference of the shielding layer 3 and spaced 90° apart from each other.

[0052] The milling cutter 82 is driven by a servo motor, with a single - cutter power of 50 - 500 W, a rotational speed of 50 - 500 revolutions per minute, and a tool stepping speed of 0.1 - 5 mm per second. All the milling cutters 82 are synchronously started and stopped and have the same rotational speed through the same servo control system to ensure the dimensional consistency of the machining of the slot holes 31. The size of the slot holes 31 needs to be designed according to the size of the corrugated - structure shielding layer 3 to meet the communication requirements. In this embodiment, the size of the machined slot holes 31 is: (along the radial direction of the cable) length 10 - 30 mm, (along the axial direction of the cable) width 3 - 15 mm.

[0053] S5. Referring to Figures 5 to 8 As shown, a sheath extrusion mold is provided. The sheath extrusion mold includes an extrusion die core 6 and an extrusion die sleeve 7. The extrusion die core 6 includes a conical guiding portion 61 and a wire - passing portion 62 located at one end of the conical guiding portion 61. Among them, the extrusion die sleeve 7 is provided with a die cavity 71 that is adapted to be in clearance fit with the extrusion die core 6, and a diamond - shaped hole 72 located on the outer periphery of the wire - passing portion 62 is provided at the end of the die cavity 71. The wire - passing portion 62 includes a shielding - layer wire - passing hole 621 and flame - retardant rope wire - passing holes 622 located on both sides of the shielding - layer wire - passing hole 621. The shielding - layer wire - passing hole 621 is adapted for the shielding layer 3 to pass through, and the flame - retardant rope wire - passing holes 622 are adapted for the flame - retardant ropes 5 to pass through. The shielding - layer wire - passing hole 621 is a square hole, and the diagonal of the diamond - shaped hole 72 coincides with the diagonal of the shielding - layer wire - passing hole 621. Adjust the long diagonal of the diamond-shaped hole 72 to be in a horizontal state, and adjust the shielding layer 3 with the slot holes 31 so that the center line of the included angle formed by two adjacent groups of slot holes 31 coincides with the long diagonal or the short diagonal of the diamond-shaped hole 72 (ensuring that the corrugated shielding layer 3 can smoothly pass through the extrusion die core 6 in a certain direction), and then feed it into the shielding layer threading hole 621. The gap between the shielding layer threading hole 621 and the shielding layer 3 is 1-5 mm; ensure that the shielding layer 3 can smoothly pass through the shielding layer threading hole 621 to avoid jamming.

[0054] It should be noted that the center line of the included angle formed by two adjacent groups of slot holes 31 of the shielding layer 3 must be kept horizontal before entering the sheath extrusion die core 6. Otherwise, the cable will be twisted, and it is impossible to ensure that the center line of the included angle formed by two adjacent groups of slot holes 31 coincides with the long diagonal or the short diagonal of the sheath layer 4, resulting in affecting the position of the slot holes 31 and thus affecting the signal coverage angle.

[0055] S6. Install the sheath extrusion die on the head of the extruder. The sheath material is extruded from the head of the extruder, flows through the conical diversion part 61, and is extruded from the gap between the extrusion die core 6 and the extrusion die sleeve 7. At the same time, during the sheath extrusion process, a flame-retardant rope 5 made of basalt fiber is introduced into the flame-retardant rope threading hole 622. The sheath material wraps the shielding layer 3 and the flame-retardant rope 5 to finally form the sheath layer 4; S7. After the sheath layer 4 is wrapped, it is cooled and shaped to obtain the finished product of the mobile leaky coaxial cable.

[0056] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention rather than to limit them. Although the present invention has been described in detail with reference to the examples, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A mobile leaky coaxial cable, characterized in that, Comprising: Inner conductor (1); Insulating layer (2), covering the outer surface of the inner conductor (1); Shielding layer (3), covering the outer surface of the insulating layer (2), the shielding layer (3) being made of a metal strip with a corrugated structure, and four sets of slots (31) being provided on the shielding layer (3) to achieve leakage of electromagnetic wave signals; wherein, each of the slots (31) is provided at the peak of the corrugated structure, and the four sets of slots (31) are evenly distributed circumferentially along the shielding layer (3) and spaced 90° apart from each other; Sheath layer (4), covering the outer surface of the shielding layer (3); wherein, the cross-section of the sheath layer (4) is a rhombus structure and has a long diagonal and a short diagonal, and the center line of the angle formed by two adjacent sets of slots (31) coincides with the long diagonal or the short diagonal; the center of the inner conductor (1) coincides with the center of the rhombus structure; the sides of the rhombus structure are adapted to contact an installation plane, and after contacting the installation plane, the proportion of the circumference of the shielding layer (3) covered by the four sets of slots (31) is configured to enable the cable signal coverage angle to be greater than 180°; Flame-retardant rope (5), provided inside the sheath layer (4) for achieving flame-retardant physical isolation, and a plurality of the flame-retardant ropes (5) are distributed on the long diagonal and symmetrically distributed on both sides of the center of the long diagonal.

2. The mobile leaky coaxial cable according to claim 1, wherein The four sets of slots (31) together cover 50% - 90% of the circumference of the shielding layer (3).

3. A mobile leaky coaxial cable according to claim 1, characterized in that, The inner conductor (1) includes one or more metal conductors and is made of solid, hollow metal material or composite metal material.

4. A mobile leaky coaxial cable according to claim 1, characterized in that, The material of the insulating layer (2) includes polyethylene, polyvinyl chloride or polytetrafluoroethylene and is in a solid or foamed structure.

5. A mobile leaky coaxial cable according to claim 1, characterized in that, The sheath layer (4) is made of a low-smoke and halogen-free flame-retardant material.

6. A mobile leaky coaxial cable according to claim 1, characterized in that, The flame-retardant rope (5) is made of a basalt fiber rope.

7. A mobile leaky coaxial cable according to claim 1, characterized in that, The flame-retardant rope (5) includes a small-diameter flame-retardant rope (5a) and a large-diameter flame-retardant rope (5b), and one small-diameter flame-retardant rope (5a) and one large-diameter flame-retardant rope (5b) are respectively arranged on both sides of the center of the long diagonal, and the small-diameter flame-retardant rope (5a) is located on the side far from the center of the long diagonal.

8. A manufacturing method of a mobile leaky coaxial cable for manufacturing the mobile leaky coaxial cable according to any one of claims 1-7, characterized in that, Comprising: S1. Stranding one or more metal conductors to obtain the inner conductor (1); S2. On the outer surface of the inner conductor (1), extruding a solid or foamed insulating layer (2), the material of the insulating layer (2) including polyethylene, polyvinyl chloride or polytetrafluoroethylene; S3. On the outer surface of the insulating layer (2), longitudinally wrapping a metal strip, welding the overlapping seam of the metal strip, and then forming a shielding layer (3) with a periodic corrugated structure having peaks and valleys through a grooving process; S4. Provide a hollow tubular mold (8), and four cutting plane grooves (81) that are symmetrically arranged and spaced 90° apart are provided in the central hole section of the hollow tubular mold (8); pass the shielding layer (3) through the hollow tubular mold (8), and the gap between the central hole section of the hollow tubular mold (8) and the shielding layer (3) is 2-5 mm; correspondingly configure milling cutters (82) at each of the cutting plane grooves (81); Pass the shielding layer (3) through the hollow tubular mold (8), pass the milling cutter (82) through the cutting plane groove (81), and cut the peak parts of the corrugated structure of the shielding layer (3), so as to process four groups of slot holes (31) that are evenly distributed along the circumference of the shielding layer (3) and spaced 90° apart from each other; S5. Provide a sheath extrusion mold, which includes an extrusion die core (6) and an extrusion die sleeve (7), and the extrusion die core (6) includes a conical diversion part (61) and a wire threading part (62) located at one end of the conical diversion part (61); Wherein, the extrusion die sleeve (7) is provided with a cavity (71) adapted to be in clearance fit with the extrusion die core (6), and a diamond-shaped hole (72) located on the outer periphery of the wire threading part (62) is provided at the end of the cavity (71); The wire threading part (62) includes a shielding layer wire threading hole (621) and flame retardant rope wire threading holes (622) located on both sides of the shielding layer wire threading hole (621); the shielding layer wire threading hole (621) is adapted for the shielding layer (3) to pass through, and the flame retardant rope wire threading holes (622) are adapted for the flame retardant rope (5) to pass through; the shielding layer wire threading hole (621) is a square hole, and the diagonal of the diamond-shaped hole (72) coincides with the diagonal of the shielding layer wire threading hole (621); Adjust the long diagonal of the diamond-shaped hole (72) to be in a horizontal state, and adjust the shielding layer (3) with the slot holes (31), so that the center line of the included angle formed by two adjacent groups of slot holes (31) coincides with the long diagonal or the short diagonal of the diamond-shaped hole (72), and then feed it into the shielding layer wire threading hole (621), and the gap between the shielding layer wire threading hole (621) and the shielding layer (3) is 1-5 mm; S6. Install the sheath extrusion mold on the head of the extruder, extrude the sheath material from the head of the extruder, flow through the conical diversion part (61), and extrude from the gap between the extrusion die core (6) and the extrusion die sleeve (7). At the same time, during the sheath extrusion process, introduce the flame retardant rope (5) made of basalt fiber material into the flame retardant rope wire threading hole (622), and the sheath material wraps the shielding layer (3) and the flame retardant rope (5) to finally form a sheath layer (4); S7. After the sheath layer (4) is wrapped, perform cooling and shaping to obtain a finished product of a mobile leaky coaxial cable.

9. The manufacturing method of a mobile leaky coaxial cable according to claim 8, characterized in that, The milling cutter (82) is driven by a servo motor, with a single cutter power of 50 - 500 W, a rotational speed of 50 - 500 revolutions per minute, and a cutter stepping speed of 0.1 - 5 mm per second. All the milling cutters (82) achieve synchronous start-stop and consistent rotational speed through the same servo control system, ensuring the consistency of the machining dimensions of the slot holes (31).

10. The manufacturing method of a mobile leaky coaxial cable according to claim 8, characterized in that, The size of each cutting plane slot (81) is: length 50 mm, width 10 - 40 mm; the size of the slot hole (31) is: length 10 - 30 mm, width 3 - 15 mm.

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