CN104036852B - Fatigue-resistant high-speed data cable for robotic arm - Google Patents

Abstract

The invention discloses a fatigue-resistant high-speed data cable for a mechanical arm, which comprises eight metal conductor units and an aramid fiber reinforcement, wherein each metal conductor unit comprises an aramid fiber, a first tin-copper alloy conductor and a first oxygen-free copper conductor which are stranded on the outer surface of the aramid fiber, and a second tin-copper alloy conductor and a second oxygen-free copper conductor which are stranded on the outer surface of an inner conducting layer; a second polytetrafluoroethylene layer longitudinally wraps the outer surface of the cable core, and a plurality of cotton yarns are filled in gaps between the second polytetrafluoroethylene layer and the four symmetrical insulating line pairs; a cotton fiber wire is wound on the outer surface of the second polytetrafluoroethylene layer to form a buffer sliding layer, the winding direction of the cotton fiber wire is opposite to the twisting direction of the four symmetrical insulated wire pairs, a plurality of metal wires are wound on the outer surface of the buffer sliding layer side by side to form a metal shielding layer, and the winding direction of the metal wires in the metal shielding layer is opposite to that of the cotton fiber wire; and a third polytetrafluoroethylene layer is wrapped on the outer surface of the metal shielding layer. The invention has small friction coefficient, is soft and stretch-proof, does not generate friction static electricity, and can still ensure the stability of the structure and the electrical property after being frequently moved.

Description

Fatigue-resistant high-speed data cable for robotic arm

technical field

The invention relates to a data cable, in particular to a fatigue-resistant high-speed data cable for a mechanical arm.

Background technique

The structure of the traditional shielded data cable is composed of 4 sets of symmetrical signal wire pairs, wrapped with a layer of polyester tape, and then wrapped with a layer of aluminum-plastic composite tape for shielding, and the outer layer is extruded with PVC or other plastic coatings. . Symmetrical signal pairs are formed by the assembly of two copper conductors with an insulated wire covered by a layer of high-density polyethylene. Product performance meets the specification requirements of TIA/EIA568B. In order to solve the problem of electrical performance attenuation and electromagnetic interference at lower frequencies, some products are designed to braid a layer of copper wire shielding on the outer layer of the aluminum-plastic composite tape. For shielded data cables that require movement, the conductors of the symmetrical signal pairs are replaced with multiple copper stranded conductors. The data cable with this structure can guarantee the transmission performance when it is used in fixed laying and mobile occasions. However, for environments with frequent movements such as robotic arms and relatively harsh environmental conditions, the performance reliability of this type of product cannot meet the requirements. After hundreds of movements, problems such as conductor breakage, increased attenuation, and decreased anti-interference performance will occur. . In the process of moving, there is friction between the insulation, the insulation and the outer tape, and the shield. On the one hand, it is easy to generate static electricity and cause signal interference. At the same time, frequent friction will also cause the mechanical and physical properties of the insulation material to decline. A general mechanical arm will require more than 100,000 movements. If the influence of the sliding of the cable core structure cannot be solved, the problems of product fatigue resistance and shielding stability cannot be solved, and the signal transmission requirements of the mechanical arm cannot be guaranteed. At this point, it is difficult for the traditional cable structure to meet the requirements.

How to design a data cable that can ensure stable signal transmission during more than 100,000 frequent reciprocating movements has become the direction of efforts of those skilled in the art.

Contents of the invention

The invention provides a fatigue-resistant high-speed data cable for a mechanical arm. The fatigue-resistant high-speed data cable for a mechanical arm has a small friction coefficient, is soft and stretch-resistant, does not generate frictional static electricity, and can still ensure a stable structure of the mechanical arm after frequent movements. Using fatigue-resistant high-speed data cables, the tensile strength of the cable is increased by 5%, the number of times of bending resistance is increased by 10-20%, and the attenuation change value of 10,000 times of bending is less than 5%.

In order to achieve the above purpose, the technical solution adopted by the present invention is: a fatigue-resistant high-speed data cable for a mechanical arm, including eight metal conductor units and aramid fiber reinforcements, and the outer surface of the metal conductor unit is covered with an insulating polypropylene layer , the metal conductor unit includes an aramid fiber located at the center, an inner conductive layer composed of several first tin-copper alloy conductors twisted on the outer surface of the aramid fiber, a first oxygen-free copper conductor, and several second The tin-copper alloy conductor and the second oxygen-free copper conductor are stranded on the outer surface of the inner conductive layer to form an outer conductor layer, the diameters of the first tin-copper alloy conductor and the first oxygen-free copper conductor are equal, and the second tin-copper alloy conductor The diameter is equal to that of the second oxygen-free copper conductor, the diameter of the first tin-copper alloy conductor and the first oxygen-free copper conductor are larger than the diameter of the second tin-copper alloy conductor and the second oxygen-free copper conductor, and the diameter of the first tin-copper alloy conductor 1. The tin content in the second tin-copper alloy conductor accounts for 0.6%, the first tin-copper alloy conductor and the first oxygen-free copper conductor in the inner conductive layer are arranged alternately, the second tin-copper alloy conductor and the first oxygen-free copper conductor in the outer conductor layer Two oxygen-free copper conductors are arranged alternately;

The eight metal conductor units are twisted in pairs to form the first, second, third and fourth symmetrical insulated wire pairs, and the outer surfaces of each are wrapped with a first polytetrafluoroethylene tape. The first, second , the third and fourth symmetrical insulated wire pairs are twisted on the outer surface of the aramid fiber reinforcement to form a cable core;

A second polytetrafluoroethylene layer longitudinally covers the outer surface of the cable core, and the gaps between the second polytetrafluoroethylene layer and the first, second, third and fourth symmetrical insulated wire pairs are filled with several cotton yarns ;

A cotton fiber thread is wound on the outer surface of the second polytetrafluoroethylene layer to form a buffer sliding layer. The winding direction of the cotton fiber thread is opposite to the twisting direction of the first, second, third and fourth symmetrical insulated wire pairs. A metal wire is wound side by side on the outer surface of the buffer sliding layer to form a metal shielding layer, and in the metal shielding layer, the metal wire is wound opposite to the cotton fiber thread;

A third polytetrafluoroethylene layer is wrapped around the outer surface of the metal shielding layer, and an outer sheath layer is wrapped around the outer surface of the third polytetrafluoroethylene layer.

Further improvement technical scheme in above-mentioned technical scheme is as follows:

1. In the above scheme, the cotton fiber thread is sparsely wound on the outer surface of the second polytetrafluoroethylene layer.

2. In the above solution, the diameter ratio of the first tin-copper alloy conductor to the second tin-copper alloy conductor is 10:6~8.

3. In the above scheme, the diameter of the aramid reinforcement is 190~210D.

Due to the use of the above-mentioned technical solutions, the present invention has the following advantages compared with the prior art:

1. In the fatigue-resistant high-speed data cable for the mechanical arm of the present invention, the outer surfaces of the first, second, third and fourth symmetrical insulated wire pairs are wrapped with first polytetrafluoroethylene tapes and twisted to form a cable core , the second polytetrafluoroethylene layer longitudinally wraps the outer surface of the cable core, and in the frequent bending process, it overcomes the distance and distance between the first, second, third and fourth symmetrical insulated wires and their respective metal conductor units The pitch changes, thereby causing changes in electrical performance; and during frequent bending, the first, second, third and fourth symmetrical insulated wire pairs are wrapped with first polytetrafluoroethylene tapes on their respective outer surfaces, and The second polytetrafluoroethylene layer wraps the symmetrical insulated wire pair with four first polytetrafluoroethylene tapes by longitudinal wrapping, because the first polytetrafluoroethylene tape and the second polytetrafluoroethylene layer have a low coefficient of friction, High strength, corrosion resistance, good insulation performance, the friction coefficient of this strip is 0.04, which is the material with the lowest friction coefficient among solid materials at present, and it is covered by longitudinal wrapping in front of the metal shielding layer to reduce the friction caused by the wrapping structure. The increase of the friction force caused by the lap joint minimizes the impact of the structural change of the cable core during frequent bending; secondly, due to the reduction of friction force and the PTFE tape is not easy to generate static electricity, it also greatly reduces the generation of static electricity and improves performance reliability and safety.

2. In the fatigue-resistant high-speed data cable for the mechanical arm of the present invention, the gaps between the second polytetrafluoroethylene layer and the first, second, third and fourth symmetrical insulated wire pairs are filled with several cotton yarns. Cotton fiber wires are wound on the outer surface of the second polytetrafluoroethylene layer to form a buffer sliding layer. The winding direction of the cotton fiber wires is opposite to the twisting direction of the first, second, third and fourth symmetrical insulated wire pairs. The metal wire is wound on the outer surface of the buffer sliding layer to form a metal shielding layer. In this metal shielding layer, the metal wires are wound side by side and opposite to the cotton fiber thread, so as to ensure that the copper wire has enough moving position without stretching when bending It causes disconnection, and at the same time, it is easier to slide between the copper wire and the insulating sliding layer without electrostatic interference. This structure can not only ensure the softness of the cable, but also ensure the shielding effect after frequent bending.

3. In the fatigue-resistant high-speed data cable for the mechanical arm of the present invention, a second polytetrafluoroethylene layer is sequentially arranged between the cable core and the outer sheath layer, and a cotton fiber thread is wound around the second polytetrafluoroethylene layer. A buffer sliding layer is formed on the outer surface of the layer, and several metal wires are wound side by side around the buffer sliding layer to form a metal shielding layer. A third polytetrafluoroethylene layer is wrapped around the outer surface of the metal shielding layer. A buffer is formed between the sleeves to avoid electrostatic interference between the outer sheath and the shielding layer during the reciprocating movement of the cable. At the same time, the performance of the PTFE tape is relatively soft and smooth, which will not affect the softness of the cable. Through the process control of the sheath extrusion, the smooth surface makes it easy to produce friction between the cable core and the sheath during the bending process. Sliding, reducing the stretching of copper conductor and tinned copper wire braid by external force, prolonging the service life.

4. The fatigue-resistant high-speed data cable for the mechanical arm of the present invention, its metal conductor unit includes the aramid fiber at the center, the inner conductive layer composed of several tin-copper alloy conductors twisted on the outer surface of the aramid fiber, and several An oxygen-free copper conductor is stranded on the outer surface of the inner conductive layer to form an outer conductor layer, which improves the tensile strength and ensures the stability of the aramid fiber in the center of the cable structure; the first, second, third and fourth symmetry Insulated wire pairs are twisted on the outer surface of an aramid fiber reinforcement to form a cable core; to ensure the stability of the cable structure, the tensile strength of the product is increased by more than 300%, the number of bending resistance is increased by 300~500%, and the attenuation change value of 10,000 times of bending less than 2%.

5. The fatigue-resistant high-speed data cable for the mechanical arm of the present invention, the metal conductor unit includes the aramid fiber located in the center, the first tin-copper alloy conductors twisted on the outer surface of the aramid fiber, the first oxygen-free copper The inner conductive layer composed of conductors is composed of several second tin-copper alloy conductors and second oxygen-free copper conductors twisted on the outer surface of the inner conductive layer to form an outer conductor layer. The first tin-copper alloy conductor and the first oxygen-free copper The diameters of the conductors are equal, the diameters of the second tin-copper alloy conductor and the second oxygen-free copper conductor are equal, and the diameters of the first tin-copper alloy conductor and the first oxygen-free copper conductor are larger than the second tin-copper alloy conductor and the second oxygen-free copper conductor. The diameter of the copper conductor, the tin content of the first tin-copper alloy conductor and the second tin-copper alloy conductor accounts for 0.6%, the first tin-copper alloy conductor and the first oxygen-free copper conductor are arranged alternately in the inner conductive layer, and the In the outer conductor layer, the second tin-copper alloy conductor and the second oxygen-free copper conductor are alternately arranged, and different types of conductors and conductors with different diameters are used as conductor units. Compared with single-diameter copper conductors or alloy conductors, the electrical characteristics are improved. And anti-bending characteristics; Thirdly, the alternate mixed structure of conductors of different materials solves the uniform distribution of the tensile force of the conductors, and there is no local area of weak tensile force during bending. At the same time, it solves the uniform distribution of conductor resistance, which is more uniform during signal transmission. The differential distribution of the diameters of the first conductor and the second conductor makes the distribution of tensile stress points of the outer layer finer and more uniform. It solves the problem that the outer layer of the conductor is easily broken when it bears greater tensile force and extrusion force. At the same time, the diameter of the outer conductor is smaller, so that the surface of the stranded conductor is smoother, and the electromagnetic wave on the surface of the conductor is more uniform during signal transmission, reducing electromagnetic distortion and attenuation value.

Description of drawings

Accompanying drawing 1 is the structure schematic diagram of fatigue-resistant high-speed data cable of manipulator of the present invention;

Accompanying drawing 2 is the structure schematic diagram of buffer sliding layer and metal shielding layer of the present invention;

Accompanying drawing 3 is A-A sectional structure schematic diagram in accompanying drawing 2;

Accompanying drawing 4 is the structural representation of metal conductor unit of the present invention

Accompanying drawing 5 is the structure diagram of comparative example cable.

In the above drawings: 1. Metal conductor unit; 2. Insulated polypropylene layer; 3. The first symmetrical insulated pair; 4. The second symmetrical insulated pair; 5. The third symmetrical insulated pair; 6. The fourth symmetrical Insulated wire pair; 7. First polytetrafluoroethylene tape; 8. Cable core; 9. Second polytetrafluoroethylene layer; 10. Cotton yarn; 12. Buffer sliding layer; 13. Metal wire; 14. Metal shielding layer; 15. The third polytetrafluoroethylene layer; 16. Outer sheath layer; 17. Cotton fiber thread; 18. Polyester tape; 19. Metal braiding layer; 20. Aramid fiber; 21. Aramid reinforcement; 22. The first tin-copper alloy conductor; 23, the first oxygen-free copper conductor; 24, the second tin-copper alloy conductor; 25, the second oxygen-free copper conductor.

detailed description

The present invention will be further described below in conjunction with accompanying drawing and embodiment:

Embodiment: A fatigue-resistant high-speed data cable for a mechanical arm, including: eight metal conductor units 1 and aramid fiber reinforcements 21, the outer surface of the metal conductor units 1 is covered with an insulating polypropylene layer 2, and the metal conductors The unit 1 includes an aramid fiber 20 at the center, an inner conductive layer composed of several first tin-copper alloy conductors 22 twisted on the outer surface of the aramid fiber 20, a first oxygen-free copper conductor 23, and several second The tin-copper alloy conductor 24 and the second oxygen-free copper conductor 25 are stranded on the outer surface of the inner conductive layer to form an outer conductor layer. The diameters of the first tin-copper alloy conductor 22 and the first oxygen-free copper conductor 23 are equal, and the second The diameters of the tin-copper alloy conductor 24 and the second oxygen-free copper conductor 25 are equal, and the diameters of the first tin-copper alloy conductor 22 and the first oxygen-free copper conductor 23 are larger than that of the second tin-copper alloy conductor 24 and the second oxygen-free copper conductor 25 diameter, the tin content in the first tin-copper alloy conductor 22 and the second tin-copper alloy conductor 24 accounts for 0.6%, and the first tin-copper alloy conductor 22 and the first oxygen-free copper conductor 23 are arranged alternately in the inner conductive layer, The second tin-copper alloy conductor 24 and the second oxygen-free copper conductor 25 are arranged alternately in the outer conductor layer;

The eight metal conductor units 1 are twisted in pairs to form the first, second, third and fourth symmetrical insulated wire pairs 3, 4, 5, 6, and the outer surfaces of each are wrapped with a first polytetrafluoroethylene tape 7. The first, second, third and fourth symmetrical insulated wire pairs 3, 4, 5, 6 are stranded on the outer surface of the aramid fiber reinforcement 21 to form a cable core 8;

A second polytetrafluoroethylene layer 9 longitudinally wraps the outer surface of the cable core 8, and the second polytetrafluoroethylene layer 9 is connected to the first, second, third and fourth symmetrical insulated wire pairs 3, 4, 5 The gap between 6 and 6 is filled with several cotton yarns 10;

In the frequent bending process, the distance and pitch between the first, second, third and fourth symmetrical insulated wires and the respective metal conductor units are changed, thereby causing changes in electrical performance; and the frequent bending process Among them, the outer surfaces of the first, second, third and fourth symmetrical insulated wire pairs are wrapped with a first polytetrafluoroethylene tape, and the second polytetrafluoroethylene layer is wrapped with four fourth A symmetrical insulated pair of polytetrafluoroethylene tapes, because the first polytetrafluoroethylene tape and the second polytetrafluoroethylene layer have low friction coefficient, high strength, corrosion resistance, and good insulation performance, the friction coefficient of the tape is 0.04, which is the material with the lowest friction coefficient among solid materials at present, and it is covered by longitudinal wrapping in front of the metal shielding layer to reduce the increase of friction caused by the lap joint caused by the wrapping structure, so that the cable core will The impact of structural changes is minimized; secondly, due to the reduction of friction and the PTFE belt is not easy to generate static electricity, it also greatly reduces the generation of static electricity, improving performance reliability and safety;

A cotton fiber thread 17 is wound on the outer surface of the second polytetrafluoroethylene layer 9 to form a buffer sliding layer 12, and the winding direction of the cotton fiber thread 17 is the same as that of the first, second, third and fourth symmetrical insulated wire pairs 3, 4, 5, 6 twisting directions are opposite, several metal wires 13 are wound side by side on the outer surface of the buffer sliding layer 12 to form a metal shielding layer 14, and the metal wires 13 in the metal shielding layer 14 are wound with the cotton fiber line 17 On the contrary; to ensure that when bending, the copper wire has enough moving position without stretching to cause disconnection, and at the same time, it is easier to slide between the copper wire and the insulating sliding layer without generating electrostatic interference. This structure can not only ensure the softness of the cable, It also ensures the shielding effect after frequent bending;

A third polytetrafluoroethylene layer 15 wraps around the outer surface of the metal shielding layer 14 , and an outer sheath layer 16 wraps around the outer surface of the third polytetrafluoroethylene layer 15 . A buffer is formed between the metal shielding layer and the outer sheath to avoid electrostatic interference between the outer sheath and the shielding layer during the reciprocating movement of the cable. At the same time, the performance of the PTFE tape is relatively soft and smooth, which will not affect the softness of the cable. Through the process control of the sheath extrusion, the smooth surface makes it easy to produce friction between the cable core and the sheath during the bending process. Sliding, reducing the stretching of copper conductor and tinned copper wire braid by external force, prolonging the service life.

The above-mentioned cotton fiber thread 17 is sparsely wound on the outer surface of the second polytetrafluoroethylene layer 9 .

Comparative example: a data cable for a manipulator, including eight metal conductor units 1, the outer surface of the metal conductor units 1 is covered with an insulating polypropylene layer 2, and the metal conductor units 1 are twisted by several copper wires 11 made;

The eight metal conductor units 1 are twisted in pairs to form first, second, third and fourth symmetrical insulated wire pairs 3, 4, 5, 6, and the first, second, third and fourth symmetrical Insulated wire pairs 3, 4, 5, 6 are twisted to form a cable core 8, and a polyester tape 18 is wrapped around the outer surface of the cable core 8, and the polyester tape 18 is connected to the first, second, third and fourth The gaps between the symmetrical insulated wire pairs 3, 4, 5, and 6 are filled with several cotton yarns 10;

A metal braiding layer 19 woven by several copper wires is located on the outer surface of the polyester belt 18 , and an outer sheath layer 16 is wrapped on the outer surface of the metal braiding layer 19 .

The diameter ratio of the first tin-copper alloy conductor 22 to the second tin-copper alloy conductor 24 is 10:6~8.

The above-mentioned aramid fiber reinforcement 21 has a diameter of 190-210D.

The above-mentioned cotton fiber thread 17 is sparsely wound on the outer surface of the second polytetrafluoroethylene layer 9 .

The performance test data are shown in Table 1:

Table 1

The above-mentioned embodiments are only to illustrate the technical concept and characteristics of the present invention, and the purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and not to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention shall fall within the protection scope of the present invention.

Claims (1)

1. null1. a mechanical arm endurance high speed data cable，It is characterized in that: including: eight metallic conductor unit (1) and aramid fiber reinforcement (21)，This metallic conductor unit (1) outer surface is coated with insulation polypropylene layer (2)，Described metallic conductor unit (1) includes the aramid fiber (20) being positioned at center、Stranded in the first gun-metal conductor (22) of aramid fiber (20) outer surface by some、The inner conducting layer that first oxygen-free copper conductor (23) forms、By some second gun-metal conductors (24)、Second oxygen-free copper conductor (25) is stranded forms outer conductor layer in inner conducting layer outer surface，Described first gun-metal conductor (22) and the first oxygen-free copper conductor (23) equal diameters，Described second gun-metal conductor (24) and the second oxygen-free copper conductor (25) equal diameters，Described first gun-metal conductor (22)、First oxygen-free copper conductor (23) diameter is more than the second gun-metal conductor (24)、Second oxygen-free copper conductor (25) diameter，Described first gun-metal conductor (22)、In second gun-metal conductor (24), Theil indices accounts for 0.6%，First gun-metal conductor (22) in described inner conducting layer、First oxygen-free copper conductor (23) is alternately arranged，Second gun-metal conductor (24) in described outer conductor layer、Second oxygen-free copper conductor (25) is alternately arranged；

   Described eight metallic conductor unit (1) the most stranded formation first, second, third and fourth symmetry insulated wires are all surrounded with the first teflin tape (7) to (3,4,5,6) and first, second, third and fourth symmetry insulated wire to (3,4,5,6) each outer surface, and described first, second, third and fourth symmetry insulated wire forms cable core (8) to (3,4,5,6) are stranded in described aramid fiber reinforcement (21) outer surface；

   One second polytetrafluoroethylene floor (9) vertical bag described cable core (8) outer surface, described second polytetrafluoroethylene floor (9) and first, second, third and fourth symmetry insulated wire are filled with some cotton yarns (10) to gap between (3,4,5,6)；

   One cotton fiber line (17) is wound in described second polytetrafluoroethylene floor (9) outer surface and forms buffering sliding layer (12), this cotton fiber line (17) winding direction is contrary to (3,4,5,6) direction of lay with first, second, third and fourth symmetry insulated wire, some one metal wires (13) are wound in described buffering sliding layer (12) outer surface abreast and form metal screen layer (14), and in this metal screen layer (14), wire (13) is wound around contrary with described cotton fiber line (17)；

   One the 3rd polytetrafluoroethylene floor (15) is around being wrapped in described metal screen layer (14) outer surface, and an external sheath layer (16) is coated on described 3rd polytetrafluoroethylene floor (15) outer surface.