Reinforced photoelectric composite cable for coal mining machine

Abstract

The invention discloses a reinforced photoelectric composite cable of a coal mining machine, which belongs to the technical field of cables, and comprises a composite cable core structure, an armored protective layer and a sheath system, and the armored protective layer comprises a first steel belt, a second steel belt and a metal net braid layer, a third steel belt which is continuously bent to be of a wave structure is arranged in a cavity formed by the first steel belt and the second steel belt, the wave troughs of the third steel belt make contact with the inner wall of the first steel belt, and the wave crests of the third steel belt make contact with the inner wall of the second steel belt. The cable can be subjected to multi-dimensional mechanical property collaborative optimization under complex working conditions, the purpose of graded unloading is achieved through deformation of the steel plate, the situation that a traditional structure generally depends on rigid resistance of an armor layer is not needed, the flexibility is considered while the mechanical property is guaranteed, and the cable adapts to frequent bending scenes; and the long-term stable operation of the cable in a severe mine environment is further ensured.

Description

Technical Field

[0001] This invention belongs to the field of cable technology, and specifically relates to a reinforced optoelectronic composite cable for coal mining machines. Background Technology

[0002] Cables are flexible or rigid wire products composed of conductors, insulation layers, and protective layers, used to transmit electrical energy, electrical signals, or optical signals. Through encapsulation design, they achieve efficient and secure signal / energy transmission and are widely used in power systems, communication networks, industrial control, and construction engineering. Among them, optoelectronic composite cables are special cables that integrate power transmission and optical signal transmission functions, enabling efficient and coordinated transmission of electrical energy and optical signals simultaneously. They combine the conductivity characteristics of power cables with the optical transmission characteristics of optical cables, offering significant advantages in reducing laying costs, saving space, and simplifying system architecture. They are widely used in scenarios requiring simultaneous power supply and communication.

[0003] In the harsh environment of mines, the photoelectric composite cable not only supplies power to the coal mining machine but also transmits signals. Through its integrated design, it solves the problems of space occupation, poor anti-interference, and weak weather resistance of traditional separate wiring. It ensures that the coal mining machine can output power stably under extreme conditions such as vibration, dust, humidity, and strong electromagnetic fields, and can also achieve precise remote monitoring and control. It is a key piece of equipment to ensure safe production and efficient mining in coal mines.

[0004] Due to the extremely complex working environment in mines, fiber optic composite cables are often subjected to external forces, such as the traction of coal mining machines, the impact of falling coal and rocks, and the squeezing of hydraulic supports and the coal mining machine body. These forces can be localized or widespread, causing damage to the power system (conductors, insulation) and the optical transmission system (optical fiber), leading to cable failure. Currently, to improve cable strength and better adapt to the complex working environment of mines, multi-layer metal shielding and cavity compression-resistant designs are mainly used to improve the overall compression and torsional resistance of the cable. The multi-layer metal shielding design directly wraps the metal material around the cable core to achieve... While the purpose of "rigid resistance" is to improve compressive strength, it also significantly reduces the flexibility of the cable, resulting in high cost and weight. Cavity design, on the other hand, has the defects of poor compressive stability and susceptibility to dynamic force damage. If one end is partially damaged, the cavity structure will provide a "channel" for water vapor and coal dust, accelerating cable damage or aging. Moreover, mining cables often need to be twisted with the equipment (such as when the rocker arm of a coal mining machine swings). The cavity structure will cause the constraint between the layers (sheath, shielding layer, internal components) to decrease. During twisting, the structures on both sides of the cavity are prone to relative sliding, causing "tearing" of the shielding layer and sheath, or "entanglement and compression" of the fiber optic loose tube and conductor. Summary of the Invention

[0005] This invention addresses the problem of overly simplistic solutions in existing technologies by providing a significantly different approach. Specifically, it offers a reinforced photoelectric composite cable for coal mining machines. This addresses the shortcomings of existing reinforced photoelectric composite cables, which rely primarily on passive pressure relief due to their material properties when improving compressive strength. This approach has significant drawbacks, as it not only fails to simultaneously enhance both compressive and torsional resistance but also leads to a significant decrease in cable flexibility. Consequently, it cannot meet the multi-dimensional mechanical performance requirements of coal mining machines under complex mining conditions (such as frequent dragging, bending, torsion, and impact compression).

[0006] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows: A reinforced fiber optic composite cable for coal mining machines includes a composite core structure, an armored protective layer, and a sheath system. The armored protective layer is located between the composite core structure and the sheath system. The armored protective layer includes a first steel strip, a second steel strip, and a metal mesh braided layer. The first and second steel strips have grooved cross-sections and are spirally wound around the composite core structure. The metal mesh braided layer wraps around the structural layer formed by the second steel strip. A third steel strip with a continuously bent, wave-like structure is disposed in the cavity formed by the first and second steel strips. The troughs of the third steel strip contact the inner wall of the first steel strip, and the crests contact the inner wall of the second steel strip.

[0007] Preferably, the third steel strip has multiple through holes arranged linearly at equal intervals, and the through holes in the same length direction are grouped together. Each group of through holes is provided with a metal wire, which is spirally wound around the inner wall of the groove of the first steel strip.

[0008] Preferably, the outer wall of the second steel strip is provided with a plurality of protrusions, which are arranged in a dot matrix and fit with the pores on the metal mesh weave layer.

[0009] Preferably, the composite cable core structure includes a power unit and an optical fiber unit; The power unit includes multiple oxygen-free tin-plated soft copper conductors, each of which is provided with an extruded ETFE insulation layer, and each of which is provided with a braided shielding layer. The optical fiber unit includes a stainless steel spiral tube, inside which are two anti-bending optical fibers. The gap between the anti-bending optical fibers and the stainless steel spiral tube is filled with water-blocking gel, and an aramid anti-torsion layer is filled between the outside of the stainless steel spiral tube and the armored protective layer.

[0010] Preferably, the sheath system includes a signal transmission conductor, a power transmission conductor, and a sensing optical fiber integrating an FBG sensor. An aramid tensile layer is filled between the signal transmission conductor, the power transmission conductor, and the sensing optical fiber, and an outer sheath made of polyurethane-based composite material is disposed outside the aramid tensile layer.

[0011] Preferably, the signal transmission conductor is composed of AWG24 silver-plated copper wire and a foamed PE insulation layer.

[0012] Preferably, the power transmission conductor comprises a 3×50mm² tin-plated copper conductor and an insulating sleeve formed by a double-layer co-extrusion process, wherein the inner layer is cross-linked polyethylene and the outer layer is ethylene propylene rubber.

[0013] Preferably, the outer sheath has a thickness of 3.8 mm to 4.2 mm, and the silicon carbide particles in the polyurethane-based composite material constituting the outer sheath have a particle size of 50 μm to 100 μm.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention realizes a spiral armor structure using corrugated steel plates by setting a first steel strip, a second steel strip, a third steel strip and metal wires, so that the cable can perform multi-dimensional mechanical performance optimization under complex working conditions. It achieves graded stress relief by using the deformation characteristics of the steel plate itself. When encountering local forces, the corrugated structure can directly absorb energy through its own bending, stretching and other deformations, avoiding the force from being transmitted to the inside. When facing large area forces, the corrugated structure and the spiral winding method work together to disperse the concentrated force into distributed stress along the cable axis. Secondary stress relief is achieved through the adaptive deformation of the overall structure, changing the passive mode of the traditional structure that relies on the rigid resistance of the armor layer. This design ensures core mechanical properties such as compressive and torsional resistance, while significantly reducing the overall weight of the armor layer through the lightweight design of the corrugated steel plate and the flexible characteristics of the spiral winding. It also gives the cable excellent flexibility, which can easily adapt to dynamic scenarios such as frequent bending and twisting in mines, effectively reducing structural damage caused by the accumulation of mechanical stress, and further ensuring the long-term stable operation of the cable in the harsh environment of mines.

[0015] (2) The present invention achieves the use of a dot matrix arrangement of protrusions by setting a second steel strip, protrusions and metal mesh braiding layer, so that the protrusions on the second steel strip and the gaps of the outer metal mesh braiding layer are fitted together to form a physical lock, and a stable interlayer constraint is constructed by physical interlocking relationship. This effectively eliminates the hidden danger of relative displacement caused by dynamic force between traditional double-layer metal armor. For traditional structures, the two layers of metal armor are only constrained by the friction of the fit. When subjected to vibration, torsion and other forces, they are prone to slippage. Continuous slippage between layers will cause the metal mesh edge to wear and burr, which will then tear the inner armor or cable structure layer and destroy the protective integrity. The design of this application uses the interlocking of protrusions and mesh to form a mechanically linked whole between the two layers. This not only avoids damage to the metal mesh caused by repeated friction due to displacement, but also prevents sharp breaks from cutting and damaging the inner armor. At the same time, it ensures that the two layers can work together to unload external forces, reducing structural failure caused by local stress concentration, and significantly improving the overall protective reliability and service life of the armor system.

[0016] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is an exploded view of the armored protective layer of the present invention; Figure 3 This is a schematic diagram of the connection between the third steel strip and the metal wire in this invention; Figure 4 For the present invention Figure 2 Enlarged diagram of area A in the middle; Figure 5 This is a schematic diagram of the composite cable core structure of the present invention; Figure 6 This is a plan view of the sheath system of the present invention.

[0018] In the diagram: 1. Composite cable core structure; 11. Power unit; 111. Oxygen-free tin-plated soft copper conductor; 112. ETFE insulation layer; 113. Shielding layer; 12. Fiber optic unit; 121. Stainless steel spiral tube; 122. Bending-resistant fiber; 123. Water-blocking gel; 13. Aramid anti-torsion layer; 2. Armored protective layer; 21. First steel strip; 22. Second steel strip; 221. Raised dot; 23. Third steel strip; 231. Through hole; 24. Metal wire; 25. Metal mesh braided layer; 3. Sheath system; 31. Signal transmission conductor; 32. Power transmission conductor; 33. Sensing fiber; 34. Aramid tensile layer; 35. Outer sheath. Detailed Implementation

[0019] To facilitate understanding of the present invention, a more comprehensive description of the present invention will be given below with reference to the accompanying drawings, which illustrate several embodiments of the present invention. However, the present invention can be implemented in different forms and is not limited to the embodiments described in the text. Rather, these embodiments are provided to make the disclosure of the present invention more thorough and complete.

[0020] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly associated with those skilled in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments and is not intended to limit the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] Example 1, please refer to the appendix for details. Figure 1-6 As shown, a reinforced photoelectric composite cable for coal mining machines includes a composite core structure 1, an armored protective layer 2, and a sheath system 3. The armored protective layer 2 is located between the composite core structure 1 and the sheath system 3. The armored protective layer 2 includes a first steel strip 21, a second steel strip 22, and a metal mesh braided layer 25. The cross-section of the first steel strip 21 and the second steel strip 22 is a groove structure, and the first steel strip 21 and the second steel strip 22 are spirally wound around the outside of the composite core structure 1. The metal mesh braided layer 25 wraps around the structural layer formed by the second steel strip 22. A third steel strip 23 with a continuously bent wavy structure is provided in the cavity formed by the first steel strip 21 and the second steel strip 22. The troughs of the third steel strip 23 contact the inner wall of the first steel strip 21, and the crests contact the inner wall of the second steel strip 22. The first steel strip 21 and the second steel strip 22 can be combined by overlapping.

[0023] The above structure enables the cable to achieve a spiral armor structure using corrugated steel plates, allowing for multi-dimensional optimization of mechanical properties under complex working conditions. The deformation of the steel plate itself achieves graded stress relief. Local forces are absorbed by the corrugated structure, while large-area forces are dispersed and relieved by the corrugated structure in conjunction with the spiral structure. Unlike traditional structures, it does not rely on the rigidity of the armor layer. While ensuring mechanical performance, it reduces the overall weight of the armor and also takes into account flexibility to adapt to frequent bending scenarios, further ensuring the long-term stable operation of the cable in the harsh environment of mines.

[0024] Example 2, please refer to the appendix for details. Figure 2 , Figure 3 and Figure 4As shown, the third steel strip 23 has multiple through holes 231 arranged linearly at equal intervals, and the through holes 231 in the same length direction are grouped together. Each group of through holes 231 is provided with a metal wire 24. The metal wire 24 is spirally wound on the inner wall of the groove of the first steel strip 21. Through the metal wire 24, the third steel strip 23 is stably wound on the inner wall of the groove of the first steel strip 21, that is, outside the composite cable core structure 1, and the stability of the spiral winding of the third steel strip 23 is improved. The outer wall of the second steel strip 22 is provided with multiple protrusions 221. The protrusions 221 are arranged in a dot matrix, and the protrusions 221 are matched with the pores on the metal mesh braided layer 25. The physical interlocking relationship is used to build a stable interlayer constraint, which effectively eliminates the hidden danger of relative displacement caused by dynamic force between traditional double-layer metal armor.

[0025] The processing flow of the third steel strip 23 is as follows: First, the strip-shaped third steel strip 23 is unwound and conveyed by the winding equipment. Then, the punching equipment makes linear holes at equal intervals on the third steel strip 23. After the holes are made, the bending machine is used to continuously bend it to form a wavy structure. Next, the traction equipment passes the metal wire 24 through the through hole 231 of the wavy third steel strip 23 and pulls it to the groove of the first steel strip 21. Finally, the third steel strip 23 is distributed in a spiral shape on the composite cable core structure 1 (the punching equipment, bending machine and traction equipment are existing structures, so they are not described in detail in the figure and the instruction manual). Example 3, please refer to the appendix for details. Figure 5 and Figure 6 As shown, the composite cable core structure 1 includes a power unit 11 and an optical fiber unit 12. The power unit 11 includes multiple oxygen-free tin-plated soft copper conductors 111 (withstand voltage 10kV, conforming to MT / T818). Each oxygen-free tin-plated soft copper conductor 111 is provided with an extruded ETFE insulation layer 112, and each ETFE insulation layer 112 is provided with a braided shielding layer 113. The optical fiber unit 12 includes a stainless steel spiral tube 121. Two bending-resistant optical fibers 122 are disposed inside the stainless steel spiral tube 121. The gap between the bending-resistant optical fibers 122 and the stainless steel spiral tube 121 is filled with water-blocking gel 123. An aramid anti-torsion layer 13 (bending radius ≤ 5mm, additional loss ≤ 0.1dB / 10,000 bends) is filled between the stainless steel spiral tube 121 and the armored protective layer 2. The sheath system 3 includes a signal transmission conductor 31, a power transmission conductor 32, and a sensing optical fiber 33 with integrated FBG sensors. The integrated FBG sensors are arranged at 5m intervals. An aramid tensile layer 34 is filled between the signal transmission conductor 31, the power transmission conductor 32, and the sensing optical fiber 33. An outer sheath 35 made of polyurethane-based composite material is provided outside the aramid tensile layer 34. The signal transmission conductor 31 is composed of AWG24 silver-plated copper wire and a foamed PE insulation layer. The power transmission conductor 32 includes a 3×50mm² tin-plated copper conductor and an insulating sleeve formed by a double-layer co-extrusion process. The inner layer is cross-linked polyethylene and the outer layer is ethylene propylene rubber. The thickness of the outer sheath 35 is 3.8mm to 4.2mm, and the particle size of the silicon carbide particles in the polyurethane-based composite material constituting the outer sheath 35 is 50μm to 100μm. The outer sheath 35 is formulated by weight percentage as follows: polyurethane (TPU95A) 58%, silicon carbide (SiC) 12%, graphene nanosheets 2%, flame retardant (magnesium hydroxide + red phosphorus) 15%, antistatic agent (carbon black + quaternary ammonium salt) 8%, and anti-aging agent (benzotriazole) 5%. The preparation process is as follows: First, the above raw materials are dried at 80°C for 4 hours, then blended in a twin-screw extruder at a temperature range of 160-185°C, and then granulated underwater before secondary vulcanization.

[0026] The present invention has been described by way of example in conjunction with the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvement made by adopting the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, shall be within the protection scope of the present invention.

Claims

1. A reinforced photoelectric composite cable for coal mining machines, comprising a composite cable core structure (1), an armored protective layer (2), and a sheath system (3), wherein the armored protective layer (2) is located between the composite cable core structure (1) and the sheath system (3), characterized in that... The armored protective layer (2) includes a first steel strip (21), a second steel strip (22) and a metal mesh braided layer (25). The cross-section of the first steel strip (21) and the second steel strip (22) is a groove structure. The first steel strip (21) and the second steel strip (22) are spirally wound around the outside of the composite cable core structure (1). The metal mesh braided layer (25) is wrapped around the structural layer formed by the second steel strip (22). A third steel strip (23) with a continuous bend and a wave structure is provided in the cavity formed by the first steel strip (21) and the second steel strip (22). The trough of the third steel strip (23) is in contact with the inner wall of the first steel strip (21), and the crest is in contact with the inner wall of the second steel strip (22).

2. The reinforced photoelectric composite cable for coal mining machines according to claim 1, characterized in that, The third steel strip (23) has multiple through holes (231) arranged linearly at equal intervals, and the through holes (231) in the same length direction are a group. Each group of through holes (231) is provided with a metal wire (24), and the metal wire (24) is spirally wound on the inner wall of the groove of the first steel strip (21).

3. The reinforced photoelectric composite cable for coal mining machines according to claim 1, characterized in that, The outer wall of the second steel strip (22) is provided with a plurality of protrusions (221), the protrusions (221) are arranged in a dot matrix, and the protrusions (221) are matched with the pores on the metal mesh braided layer (25).

4. The reinforced photoelectric composite cable for coal mining machines according to claim 1, characterized in that, The composite cable core structure (1) includes a power unit (11) and an optical fiber unit (12). The power unit (11) includes a plurality of oxygen-free tin-plated soft copper conductors (111), each of the oxygen-free tin-plated soft copper conductors (111) is provided with an extruded ETFE insulation layer (112), and each of the ETFE insulation layers (112) is provided with a braided shielding layer (113). The optical fiber unit (12) includes a stainless steel spiral tube (121), and two-core anti-bending optical fibers (122) are disposed inside the stainless steel spiral tube (121). The gap between the anti-bending optical fibers (122) and the stainless steel spiral tube (121) is filled with water-blocking gel (123). An aramid anti-torsion layer (13) is filled between the outside of the stainless steel spiral tube (121) and the armored protective layer (2).

5. The reinforced photoelectric composite cable for coal mining machines according to claim 1, characterized in that, The sheath system (3) includes a signal transmission conductor (31), a power transmission conductor (32), and a sensing optical fiber (33) integrating an FBG sensor. An aramid tensile layer (34) is filled between the signal transmission conductor (31), the power transmission conductor (32), and the sensing optical fiber (33). An outer sheath (35) made of polyurethane-based composite material is provided outside the aramid tensile layer (34).

6. The reinforced photoelectric composite cable for coal mining machines according to claim 5, characterized in that, The signal transmission conductor (31) is composed of AWG24 silver-plated copper wire and foamed PE insulation layer.

7. The reinforced photoelectric composite cable for coal mining machines according to claim 5, characterized in that, The power transmission conductor (32) includes a 3×50mm² tin-plated copper conductor and an insulating sleeve formed by a double-layer co-extrusion process, with the inner layer being cross-linked polyethylene and the outer layer being ethylene propylene rubber.

8. A reinforced photoelectric composite cable for coal mining machines according to claim 5, characterized in that, The outer sheath (35) has a thickness of 3.8 mm to 4.2 mm, and the silicon carbide particles in the polyurethane-based composite material constituting the outer sheath (35) have a particle size of 50 μm to 100 μm.

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