An industrial robot swivel structure with built-in cable guide

Abstract

The application relates to a built-in cable guide groove industrial robot rotary structure, which comprises a fixed base, a rotary bearing, a driving unit, a robot arm, a cable guide assembly, the cable guide assembly comprises a first mounting plate mounted on the driving unit, a second mounting plate mounted in the robot arm, a moving plate and a double-helix flexible rubber pipe, two ends of the double-helix flexible rubber pipe are respectively mounted on the first mounting plate and the second mounting plate, the middle part of the double-helix flexible rubber pipe is mounted on the moving plate, the bottom end center of the second mounting plate is provided with a screw rod, the center of the moving plate is rotationally provided with a round nut which is screwed with the screw rod, and a double-helix cable guide groove for the cable to pass through is arranged in the double-helix flexible rubber pipe. The double-helix flexible rubber pipe is used for wrapping and protecting the cable and orderly arranging the cable, the cable is regularly twisted along with the double-helix flexible rubber pipe during rotation, and the cable is prevented from being bent, locally stress concentrated, stuck during rotation and unevenly rotated.

Description

Technical Field

[0001] This invention relates to the field of industrial robot technology, and in particular to a rotary structure for an industrial robot with a built-in cable guide groove. Background Technology

[0002] As the core transmission and connection component for the overall movement of an industrial robot, the rotary joint undertakes the core functions of body rotation, attitude adjustment, and power and control signal transmission. It is widely used in industrial production scenarios such as automated welding, handling, assembly, and painting. During continuous reciprocating rotation and oscillation operations, the integrated power cables and signal cables of the rotary joint must move synchronously with the rotating structure, making them key components for ensuring the stable operation of the robot.

[0003] Currently, most mainstream industrial robot rotary structures on the market use either externally bundled cables or simple internal through-hole cables for cable management. Externally bundled cables are directly exposed outside the rotary structure and simply secured with cable ties and protective sleeves. During the robot's high-frequency rotation and twisting, the cables are prone to friction, pulling, and compression with the robot body and external workpieces. Long-term operation can lead to cable sheath wear, internal wire breakage, signal interference, and other malfunctions. Furthermore, external cables occupy external space, easily accumulating dust and oil, making maintenance difficult and severely impacting the robot's operational stability and lifespan.

[0004] The simple built-in through-hole rotary structure only has a circular through-hole in the center of the rotary spindle for cable routing, without a dedicated cable guide or limiting structure. When the robot rotates and swings significantly, the cable will twist, stack, and bend disorderly inside the through-hole, which can easily lead to excessive cable bending and localized stress concentration. This not only accelerates cable aging and damage but also causes the rotary structure to jam, resulting in uneven rotational resistance and reduced robot motion accuracy.

[0005] In view of the shortcomings of existing technologies, such as poor cable protection, messy wiring, and stress concentration, there is an urgent need to develop an industrial robot rotary structure with built-in cable guide channels that has a reasonable structure, neat wiring, and excellent protection performance, so as to solve many of the deficiencies of existing technologies. Summary of the Invention

[0006] The purpose of this invention is to overcome the above-mentioned problems in the prior art and provide an industrial robot rotary structure with a built-in cable guide groove.

[0007] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution: An industrial robot rotary structure with a built-in cable guide groove includes a fixed base, a slewing bearing, a drive unit, and a robot arm. The robot arm is rotatably supported above the fixed base by the slewing bearing. The drive unit is installed in the fixed base, and its output end is connected to the robot arm. The structure also includes a cable guide assembly comprising a first mounting plate, a second mounting plate, a motion plate, and a double-helix flexible rubber tube. The first mounting plate is mounted on the drive unit, and the second mounting plate is mounted in the robot arm. The two ends of the double-helix flexible rubber tube are respectively mounted on the first and second mounting plates, and the middle part of the double-helix flexible rubber tube is mounted on the motion plate. A screw is provided at the center of the bottom end of the second mounting plate, and a round nut that engages with the screw is rotatably mounted at the center of the motion plate. A guide rod is provided at the top end of the first mounting plate, and a guide hole is provided on the round nut that fits onto the guide rod. A double-helix cable guide groove for the cable to pass through is provided in the double-helix flexible rubber tube.

[0008] The double-helix flexible rubber tube comprises, from bottom to top, a first straight segment, a first spiral segment, a second straight segment, a second spiral segment, and a third straight segment. The spiral direction of the first spiral segment is opposite to that of the second spiral segment. A first circular hole is provided on the first mounting plate at a position off-center, and the first straight segment fits into the first circular hole. A second circular hole is provided on the second mounting plate at a position off-center, and the third straight segment fits into the second circular hole. A third circular hole is provided on the moving plate at a position off-center, and the second straight segment fits into the third circular hole.

[0009] The first straight segment is provided with a pair of first rubber limiting rings for clamping the first mounting plate, and the third straight segment is provided with a pair of second rubber limiting rings for clamping the second mounting plate.

[0010] The length of the second straight segment is equal to the thickness of the moving plate.

[0011] The helical direction of the thread on the screw is the same as the helical direction of the second thread segment.

[0012] The first and second straight segments are equipped with cable isolation frames that are sandwiched between the cables.

[0013] A clamp is installed on the outside of the first straight segment and the second straight segment respectively.

[0014] The inner wall of the double-helix flexible rubber tube is coated with electrical insulating silicone grease.

[0015] The central axis of the guide rod is parallel to the central axis of the screw.

[0016] The round nut has a limiting flange that protrudes outward along the radial direction of the bottom outer periphery, and a circular limiting plate is installed at the top of the round nut. The moving plate is located between the limiting flange and the limiting plate.

[0017] The beneficial effects of this invention are as follows: A cable guiding assembly with a cable guide groove is installed between the drive unit and the robot arm. The industrial robot's cable is threaded through the cable guiding groove. When the drive unit drives the robot arm to rotate, the two spiral segments of the double-helix flexible rubber tube rotate in opposite directions, causing one spiral segment to unwind and the other spiral segment to wind up. At the same time, the screw drives the round nut to move along the guide rod, causing the motion plate to move towards the unwinding spiral segment, providing axial space for the winding spiral segment. This cable guiding assembly, on the one hand, uses the double-helix flexible rubber tube to wrap and protect the cable and organize it in an orderly manner. On the other hand, during rotation, the cable follows the double-helix flexible rubber tube to twist regularly, avoiding cable bending, local stress concentration, rotation jamming, and uneven rotational resistance. Attached Figure Description

[0018] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the cable guiding assembly in this invention; Figure 2 This is a schematic diagram of the assembly of the first mounting plate, the second mounting plate, the moving plate, the screw, the round nut, and the guide rod in this invention. Figure 3 This is a schematic diagram of the structure of the first mounting plate and the guide rod combined in this invention; Figure 4 This is a schematic diagram of the structure of the second mounting plate and the screw in this invention; Figure 5 This is a schematic diagram of the motion plate in this invention; Figure 6 This is a schematic diagram of the structure of the round nut in this invention; Figure 7 This is a schematic diagram of the assembly structure of the double-helix flexible rubber tube, clamp, and cable isolation frame in this invention; Figure 8 This is a schematic diagram of the double-helix flexible rubber tube in this invention; Figure 9 This is a schematic diagram of the cable isolation frame in this invention; Figure 10 This is a schematic diagram of the rotary structure of the industrial robot in this invention; Figure 11This is a schematic diagram of the assembly structure of the slewing bearing, drive unit, robot arm, and cable guide assembly in this invention; The labels in the diagram are as follows: Fixed base 1, slewing bearing 2, drive unit 3, servo motor 31, hollow RV reducer 32, robot arm 4. Cable guiding assembly 5, first mounting plate 51, first round hole 511, second mounting plate 52, second round hole 521, moving plate 53, third round hole 531, double helix flexible rubber tube 54, first straight section 541, first helical section 542, second straight section 543, second helical section 544, third straight section 545, first rubber limiting ring 546, second rubber limiting ring 547, cable isolation frame 548, cable limiting groove 5481, clamp 549, screw 55, round nut 56, guide hole 561, limiting flange 562, limiting plate 563, guide rod 57, cable guiding groove 58. Cable 100. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0020] like Figures 1 to 11 As shown, an industrial robot rotary structure with a built-in cable guide groove includes a fixed base 1, a slewing bearing 2, a drive unit 3, and a robot arm 4. The robot arm 4 is rotatably supported above the fixed base 1 by the slewing bearing 2. The drive unit 3 is installed in the fixed base 1, and the output end of the drive unit 3 is connected to the robot arm 4. The drive unit 3 includes a servo motor 31 and a hollow RV reducer 32. The motor shaft of the servo motor 31 is connected to the power input port of the hollow RV reducer 32. The bottom of the robot arm is connected to the rotating disk of the hollow RV reducer with screws. When the servo motor is powered on, it drives the hollow RV reducer 32 to rotate, thereby driving the robot arm 4 to rotate.

[0021] The industrial robot rotary structure also includes a cable guide assembly 5, which includes a first mounting plate 51, a second mounting plate 52, a motion plate 53, and a double-helix flexible rubber tube 54.

[0022] The first mounting plate 51 is mounted on the drive unit 3. Specifically, the first mounting plate 51 is connected to the housing of the hollow RV reducer 32 with screws.

[0023] The second mounting plate 52 is installed in the robot arm 4. Specifically, the second mounting plate 52 is connected to the robot arm 4 with screws.

[0024] A screw 55 is provided at the bottom center of the second mounting plate 52. A round nut 56 that is screwed into the screw 55 is rotatably mounted at the center of the moving plate 53. A limiting flange 562 that protrudes outward along the radial direction of the round nut 56 is provided on the bottom outer periphery of the round nut 56. A circular limiting plate 563 is installed at the top of the round nut 56. The moving plate 53 is located between the limiting flange 562 and the limiting plate 563.

[0025] The top of the first mounting plate 51 is provided with a guide rod 57, and the central axis of the guide rod 57 is parallel to the central axis of the screw 55. The round nut 56 is provided with a guide hole 561 that fits on the guide rod 57.

[0026] The double-helix flexible rubber tube 54 is provided with a double-helix cable guide groove 58 for the cable to pass through. The inner wall of the double-helix flexible rubber tube 54 is coated with electrical insulating silicone grease to reduce the friction between the cable passing through the cable guide groove 58 and the inner wall of the double-bolt flexible rubber tube 54.

[0027] The double-helix flexible rubber tube 54 includes, from bottom to top, a first straight section 541, a first spiral section 542, a second straight section 543, a second spiral section 544, and a third straight section 545. The spiral direction of the first spiral section 542 is opposite to that of the second spiral section 544, and the spiral direction of the thread on the screw 55 is the same as that of the second thread section 544.

[0028] The two ends of the double-helix flexible rubber tube 54 are respectively mounted on the first mounting plate 51 and the second mounting plate 52, and the middle part of the double-helix flexible rubber tube 54 is mounted on the moving plate 53. Specifically, the first mounting plate 51 has a first circular hole 511 off-center, and the first straight segment 541 is fitted into the first circular hole 511. The second mounting plate 52 has a second circular hole 521 off-center, and the third straight segment 545 is fitted into the second circular hole 521. The moving plate 53 has a third circular hole 531 off-center, and the second straight segment 543 is fitted into the third circular hole 531.

[0029] A pair of first rubber limiting rings 546 are provided on the first straight segment 541 to clamp the first mounting plate 51, and a pair of second rubber limiting rings 547 are provided on the third straight segment 545 to clamp the second mounting plate 52. The length of the second straight segment 543 is equal to the thickness of the moving plate 53. This is to prevent the first straight segment 541 from moving axially relative to the first mounting plate 51, the third straight segment 545 from moving axially relative to the second mounting plate 52, and the second straight segment 543 from moving axially relative to the moving plate during rotation.

[0030] Cable separators 548 are installed in the first straight segment 541 and the second straight segment 543 to clamp the cables. The cable separator 548 has five cable limiting grooves 5481 arranged in a circular array on its side. A clamp 549 is installed on the outside of each of the first and second straight segments 541 and 543, respectively. The cable separators 548 separate the cables, preventing them from being squeezed together by the clamps 549.

[0031] Design Principle: A cable guide assembly with cable guide grooves is installed between the drive unit and the robot arm. The industrial robot's cable is threaded through the cable guide grooves. When the drive unit drives the robot arm to rotate, the first and second spiral segments of the double-helix flexible rubber tube rotate in opposite directions. One scenario is that the first spiral segment unwinds while the second spiral segment winds up, simultaneously driving the screw-driven round nut to move along the guide rod, causing the motion plate to move towards the unwinding first spiral segment, providing axial space for the winding second spiral segment. Another scenario is that the second spiral segment unwinds while the first spiral segment winds up, simultaneously driving the screw-driven round nut to move along the guide rod, causing the motion plate to move towards the unwinding second spiral segment, providing axial space for the winding first spiral segment. This allows the cable to twist regularly along with the double-helix flexible rubber tube, avoiding cable bending, localized stress concentration, rotational jamming, and uneven rotational resistance.

[0032] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0033] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. A rotary structure for an industrial robot with a built-in cable guide groove, comprising a fixed base, a slewing bearing, a drive unit, and a robot arm, wherein the robot arm is rotatably supported above the fixed base by the slewing bearing, the drive unit is installed in the fixed base, and the output end of the drive unit is connected to the robot arm, characterized in that: It also includes a cable guiding assembly, which comprises a first mounting plate, a second mounting plate, a motion plate, and a double-helix flexible rubber tube. The first mounting plate is mounted on the drive unit, the second mounting plate is mounted in the robot arm, the two ends of the double-helix flexible rubber tube are respectively mounted on the first mounting plate and the second mounting plate, and the middle part of the double-helix flexible rubber tube is mounted on the motion plate. A screw is provided at the bottom center of the second mounting plate, and a round nut that engages with the screw is rotatably mounted at the center of the motion plate. A guide rod is provided at the top of the first mounting plate, and a guide hole that fits onto the guide rod is provided on the round nut. A double-helix cable guiding groove for the cable to pass through is provided in the double-helix flexible rubber tube.

2. The industrial robot rotary structure according to claim 1, characterized in that: The double-helix flexible rubber tube comprises, from bottom to top, a first straight segment, a first spiral segment, a second straight segment, a second spiral segment, and a third straight segment. The spiral direction of the first spiral segment is opposite to that of the second spiral segment. A first circular hole is provided on the first mounting plate at a position off-center, and the first straight segment fits into the first circular hole. A second circular hole is provided on the second mounting plate at a position off-center, and the third straight segment fits into the second circular hole. A third circular hole is provided on the moving plate at a position off-center, and the second straight segment fits into the third circular hole.

3. The industrial robot rotary structure according to claim 2, characterized in that: A pair of first rubber limiting rings for clamping the first mounting plate are provided on the first straight segment, and a pair of second rubber limiting rings for clamping the second mounting plate are provided on the third straight segment.

4. The industrial robot rotary structure according to claim 2, characterized in that: The length of the second straight segment is equal to the thickness of the moving plate.

5. The industrial robot rotary structure according to claim 2, characterized in that: The helical direction of the thread on the screw is the same as the helical direction of the second thread segment.

6. The industrial robot rotary structure according to claim 2, characterized in that: Cable isolation frames are installed between the cables in the first and second straight segments.

7. The industrial robot rotary structure according to claim 2, characterized in that: A clamp is installed on the outside of the first straight segment and the second straight segment respectively.

8. The industrial robot rotary structure according to claim 1, characterized in that: The inner wall of the double-helix flexible rubber tube is coated with electrical insulating silicone grease.

9. The industrial robot rotary structure according to claim 1, characterized in that: The central axis of the guide rod is parallel to the central axis of the screw.

10. The industrial robot rotary structure according to claim 1, characterized in that: The bottom outer periphery of the round nut is provided with a limiting flange that protrudes outward along the radial direction of the round nut, and a circular limiting plate is installed at the top of the round nut. The moving plate is located between the limiting flange and the limiting plate.

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