A bend-resistant flexible cable for a robot

Abstract

The present application relates to the technical field of industrial robot cable, and discloses a bending-resistant flexible cable for robot, wherein the flexible cable comprises a central tensile core, a conductor layer, a segmented sliding liner tube and a bending preformed framework.The segmented sliding liner tube is composed of a plurality of PTFE short tubes connected end to end, annular gaps are left between adjacent short tubes, and each short tube is independently formed into clearance fit with the corresponding conductor layer.The bending preformed framework is composed of a plurality of arc-shaped rigid guide tiles hingedly connected in series, and is sleeved on the outside of the cable segment in the dense joint area.

Description

Technical Field

[0001] This invention relates to the field of industrial robot cable technology, and more specifically, to a bend-resistant flexible cable for robots. Background Technology

[0002] The fourth to sixth axes of the end effector of a six-axis industrial robot are a densely packed area of ​​rotary joints, with extremely short distances between the three joints. The flexible cable passing through this area needs to undergo multiple continuous reverse bends within an axial length of less than 20mm.

[0003] Existing flexible cables use a continuous, integrated PTFE sliding liner sleeved on the outside of the conductor layer. The bending stress is released by the axial micro-slippage between the conductor layer and the liner when bending, and the bending stress is dispersed by a variable pitch stranding method.

[0004] In the aforementioned densely jointed region, the length of the straight transition section between two adjacent bending points is less than one stranding pitch. The stress uniform distribution function of variable pitch stranding fails due to the lack of a gradual transition length. When the cable forms an S-shaped reverse bend, the axial slip direction between the continuous PTFE liner and the conductor layer is opposite at two adjacent bending points. The reverse slip is transmitted along the continuous liner and cancels each other out in a very short section, causing the conductor in that section to be effectively locked and unable to slip. The copper wire on the outer side of the bend bears concentrated tensile stress, accelerating conductor fatigue fracture. Summary of the Invention

[0005] This invention provides a bend-resistant flexible cable for robots, solving the technical problem of conductor fatigue fracture in the dense joint area of ​​the end effector of a six-axis industrial robot when the cable undergoes multiple continuous reverse bends within an axial length of less than 20mm.

[0006] This invention discloses a bend-resistant flexible cable for robots, comprising a central tensile core, a conductor layer, a segmented sliding bushing, and a bend-preformed skeleton. The central tensile core is centrally located along the cable axis. The conductor layer is spirally wound around the outside of the central tensile core. The segmented sliding bushing is composed of multiple PTFE short tubes connected end-to-end along the cable axis and fitted onto the outside of the conductor layer. An annular gap is left between adjacent PTFE short tubes, and each PTFE short tube forms an independent coaxial clearance fit with the conductor layer within its coverage area. During bending, each PTFE short tube independently undergoes axial micro-slippage with its corresponding conductor layer. The bend-preformed skeleton is fitted onto the outside of the cable segment and is composed of multiple arc-shaped rigid guide tiles arranged in series along the cable axis. The ends of adjacent arc-shaped rigid guide tiles are connected by hinges, and each arc-shaped rigid guide tile swings relative to the other around the hinge axis, converting the joint rotational motion into bending deformation of the cable along a preset curvature path.

[0007] Furthermore, each of the two adjacent arc-shaped rigid guide tiles has a hinge lug at its end. The hinge lugs are connected by a pin to form a rotating pair, and the axis of the pin is perpendicular to the bending plane. A torsion spring is fitted on the pin at each hinge, and the two ends of the torsion spring abut against the two adjacent arc-shaped rigid guide tiles respectively. When there is no external force, the torsion spring provides a restoring torque to restore the adjacent arc-shaped rigid guide tiles to their initial relative angle. The pin end is limited by a retaining ring to prevent the pin from disengaging along its axial direction.

[0008] Furthermore, each arc-shaped rigid guide tile is an arc-shaped groove, the inner cavity of which encompasses the outer circumference of the cable, and the curvature of its arc surface matches the bending radius of the corresponding joint. An axial guide groove extending along the arc length is formed on the inner wall of each arc-shaped rigid guide tile. Radially protruding sliding protrusions are fixed at axial intervals on the outer wall of the cable. These sliding protrusions are embedded in the axial guide grooves on the inner wall of the corresponding arc-shaped rigid guide tile, and the outer surface of the sliding protrusions forms a sliding fit with the groove wall of the axial guide groove. This allows the cable to be radially constrained and positioned in the cross-sectional direction of the axial guide groove while retaining sliding freedom along the length of the axial guide groove.

[0009] Furthermore, an elastic buffer pad is fixedly installed at each end of the axial guide groove. When the sliding protrusion slides to the end of the axial guide groove, the elastic buffer pad contacts the end face of the sliding protrusion and absorbs the impact force, thus limiting the axial travel of the sliding protrusion.

[0010] Furthermore, the sliding protrusion is an annular flange, which is integrally fixed to the outer wall of the cable insulation core and protrudes radially, and the axial guide groove is an annular guide groove that runs circumferentially through the inner wall of the arc-shaped rigid guide tile.

[0011] Furthermore, the groove wall of the axial guide groove maintains a tight sliding fit with the side of the sliding protrusion, and the axial guide groove on the inner wall of each arc-shaped rigid guide tile applies a radial constraint force to the sliding protrusion through the groove wall, limiting the radial position of the cable to the center of the inner cavity of the arc-shaped rigid guide tile.

[0012] Furthermore, the central tensile core is composed of aramid fiber braided rope, which is arranged along the entire length of the cable axis. The conductor layer is made of multiple sets of copper alloy wires wound around the outer circumference of the central tensile core in an alternating reverse spiral twisting manner. The gaps between the sets of copper alloy wires are filled with silicone rubber elastic filler strips, which extend along the spiral gaps between the sets of copper alloy wires.

[0013] Furthermore, each PTFE short tube has a length of 8 to 15 mm, and the axial gap of the annular gap between two adjacent PTFE short tubes is 1 to 2 mm. The inner wall of each PTFE short tube is coated with a dry film lubricating layer, and the inner diameter of each PTFE short tube is larger than the outer diameter of the conductor layer.

[0014] Furthermore, the segmented sliding liner is sequentially covered with an insulation layer, a shielding layer, and an outer sheath. The insulation layer covers each PTFE short pipe segment and the annular gap between segments to form a continuous insulation layer. The shielding layer is made of spirally overlapped copper foil strips wrapped around the outer circumference of the insulation layer. The outer sheath consists of an inner layer and an outer layer; the inner layer is a thermoplastic polyurethane elastomer layer, and the outer layer is a cross-linked polyolefin wear-resistant layer.

[0015] Furthermore, the arc-shaped rigid guide tiles at both ends of the curved preformed skeleton are fixed to the corresponding joint housing by clamps, so that the curved preformed skeleton moves synchronously with the joint.

[0016] This invention solves the technical problem of conductor locking caused by reverse slippage cancellation in extremely short transition sections of a continuous, integral PTFE liner by decomposing it into multiple independent PTFE short tubes. The annular gaps between the segments structurally cut off the continuous axial transmission path of slippage, achieving the technical effect of allowing the conductor layer at each bending point to slide independently and release bending tensile stress. By using articulated, series-connected arc-shaped rigid guide tiles to constrain the cable bending shape to a preset curvature path, this invention solves the technical problem of the variable pitch stress homogenization function failing in extremely short transition sections, achieving the technical effect of eliminating uncontrollable free bending deformation of the cable in extremely short transition sections through external curvature constraint. Through the sliding engagement of the axial guide groove and the sliding protrusion, this invention solves the technical problem of lateral displacement or local buckling of the cable due to radial unconstraint during multi-segment continuous reverse bending switching, achieving the technical effect of providing radial positioning constraint for the cable while retaining axial sliding freedom. Attached Figure Description

[0017] Figure 1 This is a front view of the bending preform skeleton of the bend-resistant flexible cable for robots according to the present invention; Figure 2 This is a longitudinal sectional view of the bend-resistant flexible cable for robots according to the present invention; Figure 3 This is a cross-sectional view of the bend-resistant flexible cable for robots according to the present invention; Figure 4 This is a schematic diagram of the structure of the arc-shaped rigid guide tile of the present invention; Figure 5 This is an isometric view of the bending preform skeleton of the flexible cable for robots according to the present invention.

[0018] In the diagram: Central tensile core-1; Conductor layer-2; Silicone rubber elastic filler strip-3; PTFE short tube-4; Annular gap-5; Insulation layer-6; Shielding layer-7; Inner layer of outer sheath-8; Outer layer of outer sheath-9; Arc-shaped rigid guide tile-10; Hinge lug-11; Pin-12; Torsion spring-13; Axial guide groove-14; Elastic buffer pad-15; Sliding protrusion-16; Clamp-17; Retaining ring-18. Detailed Implementation

[0019] The end effector of a six-axis industrial robot has three axes (fourth to sixth axes) that are densely packed rotary joints with extremely short joint spacing. Flexible cables passing through this area need to undergo multiple continuous reverse bends within an axial length of less than 20mm. Existing flexible cables use a continuous, integrated PTFE sliding liner sleeved outside the conductor layer 2 to form a gap fit. Bending stress is released by the axial micro-slippage between the conductor layer 2 and the liner during bending, while a variable pitch stranding method is used to disperse the bending stress.

[0020] In the aforementioned densely jointed region, the length of the straight transition section between two adjacent bending points is less than one stranding pitch. The stress uniform distribution function of variable pitch stranding fails due to the lack of the necessary pitch gradual transition length. Simultaneously, when the cable is forced into an S-shaped reverse bend, the axial slip direction between the continuous PTFE liner and conductor layer 2 is opposite at two adjacent bending points. Because the liner section between the two bending points is a continuous integral structure, the reverse slip is transmitted along the continuous liner and cancels each other out within a very short segment, resulting in the conductor section being effectively locked and unable to slip. The copper wire on the outer side of the bend bears concentrated tensile stress, accelerating conductor fatigue fracture.

[0021] like Figure 1-5 As shown, according to an embodiment of this invention, a bend-resistant flexible cable for robots is provided, which is used in the dense joint area of ​​the end effector of a six-axis industrial robot. It includes at least a central tensile core 1, a conductor layer 2, a segmented sliding bushing, and a bend preformed skeleton. The central tensile core 1 is centrally located along the cable axis and bears axial tension. The conductor layer 2 is spirally wound around the outside of the central tensile core 1. The segmented sliding bushing is composed of multiple PTFE short tubes 4 connected end-to-end and fitted onto the outside of the conductor layer 2. An annular gap 5 is left between adjacent PTFE short tubes 4, and each PTFE short tube 4 forms an independent coaxial clearance fit with the conductor layer 2 within its coverage area. During bending, each PTFE short tube 4 independently undergoes local axial micro-slippage with the corresponding conductor layer 2. The bend preformed skeleton is fixedly fitted onto the outside of the cable segment in the corresponding dense joint area. It is composed of multiple series-connected arc-shaped rigid guide tiles 10 connected by hinges. Each arc-shaped rigid guide tile 10 swings relative to the hinge axis as the corresponding joint rotates, converting the joint rotational motion into bending deformation of the cable along a preset curvature path.

[0022] The central tensile core 1 is made of aramid fiber braided rope. The aramid fiber braided rope is arranged along the entire length of the cable axis, and bears the axial tensile force when the cable is bent, thus limiting the axial elongation of the cable.

[0023] The conductor layer 2 is made of multiple sets of ultra-fine copper alloy wires wound around the outer periphery of the central tensile core 1 in an alternating reverse spiral twisting manner. The gaps between each set of copper alloy wires are filled with silicone rubber elastic filler strips 3, which extend along the spiral gaps between each set of copper alloy wires to provide elastic buffering and spacing maintenance for adjacent conductor sets.

[0024] The segmented sliding liner consists of multiple thin-walled PTFE short tubes 4 arranged end-to-end along the cable axis, with each PTFE short tube 4 fitted over the outer side of the conductor layer 2. Each PTFE short tube 4 is 8 to 15 mm long. An annular gap 5 with an axial clearance of 1 to 2 mm is left between adjacent PTFE short tubes 4, structurally separating them and ensuring that each PTFE short tube 4 is independent and does not contact the others axially. The inner wall of each PTFE short tube 4 is coated with a dry film lubricant layer, which reduces the sliding friction between the PTFE short tube 4 and the conductor layer 2 within its coverage area. The inner diameter of each PTFE short tube 4 is slightly larger than the outer diameter of the conductor layer 2, forming a coaxial clearance fit. This clearance allows the conductor layer 2 to slip slightly relative to the corresponding PTFE short tube 4 along the cable axis.

[0025] It should be noted that the annular gap 5 decomposes the originally continuous sliding liner into multiple independent local sliding units. When the cable has opposite axial sliding requirements at two adjacent bending points, the PTFE short pipe 4 corresponding to each bending point independently bears the sliding amount at that point, and the reverse sliding will not be transmitted to the adjacent section along the continuous pipe wall and will cancel each other out.

[0026] A curved preformed frame is fixedly fitted onto the outside of the cable segment corresponding to the dense joint area. The curved preformed frame consists of multiple arc-shaped rigid guide tiles 10 arranged in series along the cable axis. Each arc-shaped rigid guide tile 10 is arc-shaped groove, its inner cavity encompassing the outer circumference of the cable, and its arc curvature matching the bending radius of the corresponding joint. The ends of two adjacent arc-shaped rigid guide tiles 10 are respectively provided with hinge ears 11, which are connected by pins 12 to form a rotating pair. The axis of the pins 12 is perpendicular to the bending plane (i.e., arranged in the transverse direction). A torsion spring 13 is fitted on the pin 12 at each hinge point, with both ends of the torsion spring 13 abutting against two adjacent arc-shaped rigid guide tiles 10. When there is no external force, the torsion spring 13 provides a restoring force to return the adjacent arc-shaped rigid guide tiles 10 to their initial relative angle. The ends of the pins 12 are limited by retaining rings 18 to prevent the pins 12 from disengaging along their axial direction.

[0027] Each arc-shaped rigid guide tile 10 has an axial guide groove 14 extending along its arc length direction on its inner wall. The axial guide groove 14 is a strip-shaped groove that runs through the arc length direction of the inner wall of the arc-shaped rigid guide tile 10, and its cross-sectional shape matches the cross-sectional shape of the sliding protrusion 16. Sliding protrusions 16 are fixed radially at intervals along the axial direction on the outer wall of the cable's insulated core. The sliding protrusions 16 are embedded in the corresponding axial guide grooves 14 on the inner wall of the arc-shaped rigid guide tile 10, and the outer surface of the sliding protrusions 16 forms a sliding fit with the groove wall of the axial guide groove 14, so that the cable is constrained and positioned in the cross-sectional direction (i.e., radial) of the axial guide groove 14, while retaining the sliding freedom along the length direction (i.e., arc length) of the axial guide groove 14. An elastic buffer pad 15 is fixedly installed at each end of the axial guide groove 14. The elastic buffer pad 15 serves as the end limit of the travel of the sliding protrusion 16. When the sliding protrusion 16 slides to the end of the axial guide groove 14, the elastic buffer pad 15 contacts the end face of the sliding protrusion 16 and absorbs the impact force.

[0028] In some embodiments, the sliding protrusion 16 is an annular flange, which is integrally fixed to the outer wall of the insulated wire core and protrudes radially. The annular flange is embedded in the annular guide groove that runs through the inner wall of the corresponding arc-shaped rigid guide tile 10.

[0029] Furthermore, to prevent lateral displacement or local buckling of the cable during multiple consecutive reverse bending transitions, the groove wall of the axial guide groove 14 maintains a tight sliding fit with the side of the sliding protrusion 16. When the cable undergoes an S-shaped reverse bend between adjacent arc-shaped rigid guide tiles 10, the axial guide groove 14 on the inner wall of each arc-shaped rigid guide tile 10 applies a radial constraint force to the sliding protrusion 16 through the groove wall, thus limiting the radial position of the cable to the center of the inner cavity of the arc-shaped rigid guide tile 10.

[0030] Insulation layer 6 is extruded onto the outer surface of the segmented sliding liner, covering each segment of PTFE short pipe 4 and the annular gap 5 between segments, forming a continuous insulation layer. Shielding layer 7 is made of spirally overlapped copper foil strip wrapped around the outer circumference of insulation layer 6, with the copper foil strip spirally wrapped in an overlapping manner to ensure shielding continuity. Outer sheath covers the outside of shielding layer 7, and consists of an inner layer 8 of thermoplastic polyurethane elastomer and an outer layer 9 of cross-linked polyolefin wear-resistant layer. The inner layer 8 provides elastic protection, and the outer layer 9 provides wear-resistant protection.

[0031] It should be noted that when the curved preformed skeleton is fixedly sleeved on the outside of the cable, the inner cavity of each arc-shaped rigid guide tile 10 of the curved preformed skeleton encompasses the outer peripheral surface of the cable's outer sheath. The arc-shaped rigid guide tile 10 achieves sleeve positioning through the containment and cooperation between its inner cavity groove wall and the outer peripheral surface of the cable. The arc-shaped rigid guide tiles 10 at both ends of the curved preformed skeleton are fixed to the corresponding joint housing by clamps 17, so that the curved preformed skeleton moves synchronously with the joint.

[0032] The cable is installed in the dense joint area of ​​the three-axis end of the robot, and each arc-shaped rigid guide tile 10 of the bent preformed skeleton corresponds to the bending position of each joint.

[0033] When the robot joint rotates, the arc-shaped rigid guide tile 10 corresponding to that joint is driven by the joint to swing around the pin 12 relative to the adjacent arc-shaped rigid guide tile 10. The relative rotation angle between adjacent arc-shaped rigid guide tiles 10 is determined by the joint rotation angle. The curvature of the arc surface of each arc-shaped rigid guide tile 10 guides the cable to bend along a preset bending radius, converting the joint rotation motion into bending deformation of the cable along a preset curvature path.

[0034] When the cable is bent, the sliding protrusion 16 on the outer wall of the insulated core slides along the arc length direction in the axial guide groove 14 on the inner wall of the corresponding arc-shaped rigid guide tile 10. The groove wall of the axial guide groove 14 applies a radial constraint force to the sliding protrusion 16, so that the cable maintains radial positioning during bending and does not shift laterally. When the sliding protrusion 16 slides to the end of the axial guide groove 14, the elastic buffer pad 15 contacts the end face of the sliding protrusion 16 and absorbs the end impact force, limiting the axial travel of the sliding protrusion 16.

[0035] Inside the cable, the conductor layer 2 on the outer side of the bend is stretched, generating axial tensile stress. This section of conductor layer 2 undergoes slight slippage relative to its corresponding PTFE short tube 4 along the cable axis, releasing the axial tensile stress on the outer side of the bend. The slippage at each bend point is independently borne by the PTFE short tube 4 section corresponding to that bend point.

[0036] When the cable forms an S-shaped reverse bend, the conductor layer 2 at the first bend point slides in the positive direction, and the conductor layer 2 at the second bend point slides in the negative direction. Since the PTFE short tube 4 between the two bend points is broken into independent PTFE short tube 4 segments by the annular gap 5, the positive and negative sliding are independently provided by their respective corresponding PTFE short tube 4 segments. The sliding amounts in the two directions are not transmitted along the continuous tube wall and do not cancel each other out.

[0037] When the joint rotates in the opposite direction to return to its original position, the torsion spring 13 applies a restoring torque to the adjacent arc-shaped rigid guide tile 10, which helps the arc-shaped rigid guide tile 10 return to its initial relative angle, and the cable returns to its initial shape.

[0038] The segmented sliding liner in this embodiment decomposes the originally continuous PTFE liner into multiple independent PTFE short tubes 4. The annular gaps 5 between the segments structurally cut off the continuous axial transmission path of the slippage. Therefore, the reverse slippage demand generated at adjacent bending points in the S-shaped reverse bend is independently borne by their respective corresponding PTFE short tubes 4. The reverse slippage amounts no longer cancel each other out, and the conductor layer 2 at each bend apex can still slide freely to release tensile stress, overcoming the problem of the conductor being locked up due to the cancellation of reverse slippage in the extremely short transition section of the continuous liner.

[0039] The bending preformed skeleton, through articulated series of arc-shaped rigid guide tiles 10, constrains the bending angle of each joint to a preset curvature path matching the bending radius of the joint. The bending shape of the cable in the dense joint area is determined by the geometry of the bending preformed skeleton. Therefore, under the condition that the transition section length is less than one strand pitch and the variable pitch stress homogenization function fails, the bending preformed skeleton replaces the internal variable pitch stress distribution function with external curvature constraint, eliminating the possibility of uncontrollable free bending deformation of the cable in the extremely short transition section.

[0040] The axial guide groove 14 on the inner wall of the arc-shaped rigid guide tile 10 forms a sliding fit with the sliding protrusion 16 on the outer wall of the insulated wire core, providing radial positioning constraint for the cable during multiple consecutive reverse bending switching, while retaining axial sliding freedom. This fit prevents the cable from lateral displacement or local buckling due to loss of radial constraint at the moment of reverse bending switching.

[0041] The embodiments of the present invention have been described above. However, the embodiments are not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make more equivalent embodiments under the guidance of the present embodiments, and all of them are within the protection scope of the present embodiments.

Claims

1. A bend-resistant flexible cable for robots, characterized in that, include: The central tensile core (1) is arranged centered along the cable axis; The conductor layer (2) is wound around the outside of the central tensile core (1) in a spiral twisting manner; The segmented sliding liner is composed of multiple PTFE short tubes (4) connected end to end along the cable axis and sleeved on the outside of the conductor layer (2). An annular gap (5) is left between adjacent PTFE short tubes (4). Each PTFE short tube (4) forms an independent coaxial gap fit with the conductor layer (2) within its coverage area. When bending, each PTFE short tube (4) independently undergoes axial micro-slip with the corresponding conductor layer (2). The length of each PTFE short tube (4) is 8 to 15 mm, and the axial gap of the annular gap (5) between two adjacent PTFE short tubes (4) is 1 to 2 mm. The curved preformed skeleton is fitted on the outside of the cable segment in the dense joint area. It is composed of multiple arc-shaped rigid guide tiles (10) arranged in series along the cable axis. The ends of adjacent arc-shaped rigid guide tiles (10) are connected by hinges. Each arc-shaped rigid guide tile (10) swings relative to the hinge axis, converting the joint rotational motion into the bending deformation of the cable along the preset curvature path. Each arc-shaped rigid guide tile (10) is arc-shaped groove, and its inner cavity encloses the outer circumference of the cable. The curvature of its arc surface matches the bending radius of the corresponding joint. Each arc-shaped rigid guide tile (10) has an axial guide groove (14) extending along the arc length direction on its inner wall. Radially protruding sliding protrusions (16) are fixed on the outer wall of the cable at axial intervals. The sliding protrusions (16) are embedded in the axial guide grooves (14) on the inner wall of the corresponding arc-shaped rigid guide tile (10). The outer surface of the sliding protrusions (16) and the groove wall of the axial guide groove (14) form a sliding fit, so that the cable obtains radial constraint positioning in the cross section direction of the axial guide groove (14) and retains the sliding degree of freedom along the length direction of the axial guide groove (14).

2. The bend-resistant flexible cable for robots according to claim 1, characterized in that, The ends of two adjacent arc-shaped rigid guide tiles (10) are respectively provided with hinge ears (11). The hinge ears (11) are connected by pins (12) to form a rotating pair. The axis of the pins (12) is perpendicular to the bending plane. A torsion spring (13) is sleeved on the pins (12) at each hinge. The two ends of the torsion springs (13) respectively abut against the two adjacent arc-shaped rigid guide tiles (10). When there is no external force, the torsion springs (13) provide a restoring torque to make the adjacent arc-shaped rigid guide tiles (10) return to the initial relative angle. The ends of the pins (12) are limited by retaining rings (18) to prevent the pins (12) from coming out along their axial direction.

3. The bend-resistant flexible cable for robots according to claim 1, characterized in that, An elastic buffer pad (15) is fixedly installed at each end of the axial guide groove (14). When the sliding protrusion (16) slides to the end of the axial guide groove (14), the elastic buffer pad (15) contacts the end face of the sliding protrusion (16) and absorbs the impact force, thus limiting the axial travel of the sliding protrusion (16).

4. The bend-resistant flexible cable for robots according to claim 1, characterized in that, The sliding protrusion (16) is an annular flange, which is integrally fixed to the outer wall of the cable and protrudes radially. The axial guide groove (14) is an annular guide groove that runs circumferentially through the inner wall of the arc-shaped rigid guide tile (10).

5. The bend-resistant flexible cable for robots according to claim 1, characterized in that, The groove wall of the axial guide groove (14) and the side of the sliding protrusion (16) maintain a tight sliding fit. The axial guide groove (14) on the inner wall of each arc-shaped rigid guide tile (10) applies a radial constraint force to the sliding protrusion (16) through the groove wall, limiting the radial position of the cable to the center of the inner cavity of the arc-shaped rigid guide tile (10).

6. The bend-resistant flexible cable for robots according to claim 1, characterized in that, The central tensile core (1) is made of aramid fiber braided rope, which is arranged along the entire length of the cable axis; the conductor layer (2) is made of multiple sets of copper alloy wires wound around the outer circumference of the central tensile core (1) in an alternating reverse spiral twisting manner, and the gaps between each set of copper alloy wires are filled with silicone rubber elastic filler strips (3), which extend along the spiral gaps between each set of copper alloy wires.

7. The bend-resistant flexible cable for robots according to claim 1, characterized in that, The segmented sliding liner is sequentially covered with an insulation layer (6), a shielding layer (7), and an outer sheath. The insulation layer (6) covers each PTFE short pipe (4) and the annular gap (5) between the segments to form a continuous insulation covering. The shielding layer (7) is wrapped with spirally overlapped copper foil strips on the outer circumference of the insulation layer (6). The outer sheath consists of an inner layer (8) and an outer layer (9). The inner layer (8) is a thermoplastic polyurethane elastomer layer, and the outer layer (9) is a cross-linked polyolefin wear-resistant layer.

8. The bend-resistant flexible cable for robots according to claim 1, characterized in that, The curved rigid guide tiles (10) at both ends of the curved preformed skeleton are fixed to the corresponding joint shell by clamps (17), so that the curved preformed skeleton moves synchronously with the joint.

9. The bend-resistant flexible cable for robots according to claim 1, characterized in that, The inner wall of each PTFE short tube (4) is coated with a dry film lubricating layer, and the inner diameter of each PTFE short tube (4) is larger than the outer diameter of the conductor layer (2).

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