High-flame-retardant ceramic sheath radio frequency coaxial cable

Abstract

The invention discloses a high-flame-retardant ceramic sheath radio frequency coaxial cable, which improves the flame-retardant characteristic of the cable, improves the pressure resistance of the cable, reduces attenuation, improves signal strength and increases the transmission distance. The cable includes: an inner conductor; the inner layer insulation structure comprises a first flower-shaped framework sleeve, a first insulation filling layer, a second annular framework sleeve and a second insulation filling layer, the first flower-shaped framework sleeve comprises a first inner cylinder, a flower-shaped outer cylinder and scattered first connecting ribs, and the second annular framework sleeve comprises a second inner cylinder, a second outer cylinder and scattered second connecting ribs; the outer wall of the first inner cylinder is connected with the inner wall of the flower-shaped outer cylinder through a first connecting rib, and the outer wall of the second inner cylinder is connected with the inner wall of the second outer cylinder through a second connecting rib; an outer conductor; and a sheath layer, wherein the material of the sheath layer is ceramic silicone rubber.

Description

Technical Field

[0001] The invention relates to the technical field of cable structures, in particular to a highly flame-retardant ceramic sheathed radio frequency coaxial cable. Background Art

[0002] Radio frequency coaxial cables are mainly used in the wired transmission parts of wireless mobile communications, cellular phones, microwave transmission, and broadcast communication systems.

[0003] The RF coaxial cable in the prior art is composed of a cylindrical inner conductor, a solid physical foaming insulation layer, a corrugated copper tube outer conductor and an outer sheath. In the actual structure, the foaming degree of the physical foaming insulation is always limited to reduce the loss, which cannot be compared with the low loss in a vacuum environment or an air-filled environment. Because the relative dielectric constant of air (or vacuum) insulation is the smallest, the loss is the smallest. The insulation structure of nearly all air or vacuum can minimize the loss and increase the transmission distance.

[0004] Therefore, it is urgent to develop a structure that can reliably reduce the filling space of the foamed insulation layer while ensuring the reliable production of the coaxial cable.

[0005] In addition, existing coaxial cables are all made of low-smoke halogen-free polyolefin materials, and their flame retardant properties are relatively low, so there is room for further improvement of their flame retardant properties. Summary of the invention

[0006] In view of the above problems, the present invention provides a highly flame-retardant ceramic sheathed radio frequency coaxial cable, which improves the flame-retardant properties of the cable, improves the voltage resistance of the cable, reduces attenuation, increases signal strength, and increases transmission distance.

[0007] A highly flame-retardant ceramic sheathed radio frequency coaxial cable, characterized in that it comprises:

[0008] Inner conductor;

[0009] An inner insulating structure, comprising a first flower-shaped frame sleeve, a first insulating filling layer, a second annular frame sleeve, and a second insulating filling layer, wherein the first flower-shaped frame sleeve comprises a first inner cylinder, a flower-shaped outer cylinder, and scattered first connecting ribs, and the second annular frame sleeve comprises a second inner cylinder, a second outer cylinder, and scattered second connecting ribs, wherein the outer wall of the first inner cylinder is connected to the inner wall of the flower-shaped outer cylinder through the first connecting ribs, and the outer wall of the second inner cylinder is connected to the inner wall of the second outer cylinder through the second connecting ribs;

[0010] Outer conductor;

[0011] and a sheath layer, wherein the sheath layer is made of ceramic silicone rubber;

[0012] The inner conductor is arranged in the inner cavity of the first inner cylinder, the first insulating filling layer is filled in the first inner cavity of the first flower-shaped skeleton sleeve, the second insulating filling layer is filled in the second inner cavity of the second annular skeleton sleeve, the outer periphery of the flower-shaped outer cylinder of the first flower-shaped skeleton sleeve is provided with the second inner cylinder, a plurality of groups of spaced-apart gap portions are formed between the second inner cylinder and the flower-shaped outer cylinder, the outer periphery of the second outer cylinder is covered with the outer conductor, and the outer periphery of the outer conductor is covered with the sheath layer.

[0013] It is further characterized by:

[0014] The inner conductor is a copper tube or copper-clad aluminum conductor for transmitting electrical signals;

[0015] The flower-shaped outer cylinder includes six groups of outer cylinder edges with the same arc edges, and the adjacent outer cylinder edges are connected to form a six-petal-shaped outer cylinder, and the space between the outer walls of the adjacent outer cylinder edges and the inner wall of the second inner cylinder forms a group of gap parts;

[0016] The first insulating filling layer and the second insulating filling layer are both high-foam polyethylene filling layers;

[0017] The outer conductor is a metal strip longitudinally wrapped and welded into a tubular structure, the outer conductor is sleeved on the outer wall of the second outer tube, and the outer conductor and the inner conductor form an electromagnetic oscillation circuit to transmit electromagnetic;

[0018] The outer conductor is a metal wire braided outer conductor shielding layer, the outer conductor is sleeved on the outer wall of the second outer tube, and the outer conductor and the inner conductor form an electromagnetic oscillation circuit to transmit electromagnetic;

[0019] The outer sheath is processed by an extruder and coated on the outer periphery of the outer conductor. The ceramic silicone rubber has excellent fireproof, flame retardant, low smoke and non-toxic properties. The extrusion molding process is simple. The residue after combustion is a hard ceramic shell. The hard shell does not melt or drip in a fire environment. It can withstand fire at a temperature of 950°C-1000°C for 90 minutes, thereby enhancing the flame retardant and fireproof performance of the cable and having high safety and reliability.

[0020] After adopting the structure of the present invention, since the outer sheath is made of ceramic silicone rubber extrusion coating, it enhances the flame retardant and fireproof performance of the cable, and improves safety and reliability; and since the inner insulating structure is formed by a combination of a first insulating filling layer and a second insulating filling layer, and both insulating filling layers have corresponding skeleton sleeves, and a plurality of groups of spaced gaps are formed between the second inner cylinder and the flower-shaped outer cylinder, it increases the void ratio in the radial space between the inner conductor and the outer conductor, thereby improving the cable's withstand voltage performance, reducing attenuation, increasing signal strength, and increasing transmission distance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a cross-sectional schematic diagram of the present invention;

[0022] Figure 2 It is a structural schematic diagram of the inner insulating structure corresponding to the present invention;

[0023] The names corresponding to the serial numbers in the figure are as follows:

[0024] Inner conductor 10, inner insulating structure 20, outer conductor 30, sheath layer 40, first flower-shaped skeleton sleeve 50, first inner cylinder 51, flower-shaped outer cylinder 52, first connecting rib 53, first insulating filling layer 60, second annular skeleton sleeve 70, second inner cylinder 71, second outer cylinder 72, second connecting rib 73, second insulating filling layer 80, and gap portion 90. DETAILED DESCRIPTION

[0025] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0027] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0028] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0029] A highly flame retardant ceramic sheathed RF coaxial cable, see Figure 1 and Figure 2 , which includes an inner conductor 10, an inner insulating structure 20, an outer conductor 30, and a sheath layer 40;

[0030] The inner insulating structure 20 includes a first flower-shaped skeleton sleeve 50, a first insulating filling layer 60, a second annular skeleton sleeve 70, and a second insulating filling layer 80. The first flower-shaped skeleton sleeve 50 includes a first inner cylinder 51, a flower-shaped outer cylinder 52, and scattered first connecting ribs 53. The second annular skeleton sleeve 70 includes a second inner cylinder 71, a second outer cylinder 72, and scattered second connecting ribs 73. The outer wall of the first inner cylinder 51 is connected to the inner wall of the flower-shaped outer cylinder 52 through the first connecting rib 53, and the outer wall of the second inner cylinder 71 is connected to the inner wall of the second outer cylinder 72 through the second connecting rib 73.

[0031] The material of the sheath layer 40 is ceramic silicone rubber;

[0032] The inner conductor 10 is arranged in the inner cavity of the first inner cylinder 51, the first insulating filling layer 60 is filled in the first inner cavity of the first flower-shaped skeleton sleeve 50, and the second insulating filling layer 80 is filled in the second inner cavity of the second annular skeleton sleeve 70. The outer periphery of the flower-shaped outer cylinder 52 of the first flower-shaped skeleton sleeve 50 is provided with a second inner cylinder 71, and a plurality of groups of spaced gap portions 90 are formed between the second inner cylinder 71 and the flower-shaped outer cylinder 52. The outer periphery of the second outer cylinder 72 is coated with an outer conductor 30, and the outer periphery of the outer conductor 30 is coated with a sheath layer 40.

[0033] In a specific implementation, the inner conductor 10 is a copper tube or copper-clad aluminum conductor for transmitting electrical signals.

[0034] In a specific embodiment, the flower-shaped outer cylinder 52 includes six groups of outer cylinder edges 521 with the same arc edges. Adjacent outer cylinder edges 521 are connected to form a six-petal-shaped outer cylinder. The space between the outer walls of adjacent outer cylinder edges 521 and the inner wall of the second inner cylinder 71 forms a group of gap portions 90.

[0035] In a specific embodiment, the first insulating filling layer 60 and the second insulating filling layer 80 are both high-foam polyethylene filling layers.

[0036] In specific implementation, the outer conductor 30 is a metal strip longitudinally wrapped and welded into a tube structure, and the outer conductor 30 is sleeved on the outer wall of the second outer tube 72, and the outer conductor 30 and the inner conductor 10 form an electromagnetic oscillation circuit to transmit electromagnetic;

[0037] Alternatively, the outer conductor 30 is a metal wire braided outer conductor shielding layer, and the outer conductor 30 is sleeved on the outer wall of the second outer tube 72 . The outer conductor 30 and the inner conductor 10 form an electromagnetic oscillation circuit to transmit electromagnetics.

[0038] During specific implementation, the outer sheath 40 is processed by an extruder and coated on the outer periphery of the outer conductor 30. The ceramic silicone rubber has excellent fireproof, flame retardant, low smoke and non-toxic properties. The extrusion molding process is simple. The residue after combustion is a hard ceramic shell. The hard shell does not melt or drip in a fire environment. It can withstand fire at a temperature of 950℃-1000℃ for 90 minutes, thereby enhancing the flame retardant and fireproof performance of the cable and having high safety and reliability.

[0039] Its working principle is as follows: since the outer sheath is made of ceramic silicone rubber extrusion coating, it enhances the flame retardant and fireproof performance of the cable, and improves safety and reliability; and since the inner insulation structure is formed by a combination of a first insulating filling layer and a second insulating filling layer, and both insulating filling layers have corresponding skeleton sleeves, and a number of groups of spaced gaps are formed between the second inner cylinder and the flower-shaped outer cylinder, it increases the porosity in the radial space between the inner conductor and the outer conductor, thereby improving the cable's voltage resistance, reducing attenuation, increasing signal strength, and increasing transmission distance.

[0040] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0041] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A highly flame-retardant ceramic sheathed radio frequency coaxial cable, characterized in that: It includes: Inner conductor; An inner insulating structure, comprising a first flower-shaped frame sleeve, a first insulating filling layer, a second annular frame sleeve, and a second insulating filling layer, wherein the first flower-shaped frame sleeve comprises a first inner cylinder, a flower-shaped outer cylinder, and scattered first connecting ribs, and the second annular frame sleeve comprises a second inner cylinder, a second outer cylinder, and scattered second connecting ribs, wherein the outer wall of the first inner cylinder is connected to the inner wall of the flower-shaped outer cylinder through the first connecting ribs, and the outer wall of the second inner cylinder is connected to the inner wall of the second outer cylinder through the second connecting ribs; Outer conductor; and a sheath layer, wherein the sheath layer is made of ceramic silicone rubber; The inner conductor is arranged in the inner cavity of the first inner cylinder, the first insulating filling layer is filled in the first inner cavity of the first flower-shaped skeleton sleeve, the second insulating filling layer is filled in the second inner cavity of the second annular skeleton sleeve, the outer periphery of the flower-shaped outer cylinder of the first flower-shaped skeleton sleeve is provided with the second inner cylinder, a plurality of groups of spaced-apart gap portions are formed between the second inner cylinder and the flower-shaped outer cylinder, the outer periphery of the second outer cylinder is covered with the outer conductor, and the outer periphery of the outer conductor is covered with the sheath layer.

2. The highly flame-retardant ceramic sheathed radio frequency coaxial cable according to claim 1, characterized in that: The inner conductor is a conductor such as a copper tube or copper-clad aluminum for transmitting electrical signals.

3. The highly flame-retardant ceramic sheathed radio frequency coaxial cable according to claim 1, characterized in that: The flower-shaped outer cylinder comprises six groups of outer cylinder edges with the same arc edges, and adjacent outer cylinder edges are connected to form a six-petal-shaped outer cylinder, and the space between the outer walls of the adjacent outer cylinder edges and the inner wall of the second inner cylinder forms a group of gap parts.

4. The highly flame-retardant ceramic sheathed radio frequency coaxial cable according to claim 1, characterized in that: The first insulating filling layer and the second insulating filling layer are both high-foam polyethylene filling layers.

5. The highly flame-retardant ceramic sheathed radio frequency coaxial cable according to claim 1, characterized in that: The outer conductor is a metal strip longitudinally wrapped and welded into a tubular structure, and the outer conductor is sleeved on the outer wall of the second outer tube.

6. The highly flame-retardant ceramic sheathed radio frequency coaxial cable according to claim 1, characterized in that: The outer conductor is a metal wire braided outer conductor shielding layer, and the outer conductor is sleeved on the outer wall of the second outer cylinder.

7. The highly flame-retardant ceramic sheathed radio frequency coaxial cable according to claim 1, characterized in that: The outer sheath is covered on the outer circumference of the outer conductor through an extruder.

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