Multi-direction positioning anti-deviation robot arm end flange connection structure

Abstract

The application discloses a multi-direction positioning anti-deviation robot arm end flange connecting structure and relates to the technical field of robot end effector connecting. The robot arm end is provided with a first flange connecting assembly, one end of a robot executing element is provided with a second flange connecting assembly, and the first flange connecting assembly is connected with the second flange connecting assembly and used for fixing and mounting the robot executing element on the robot arm end. Through the preliminary centering cooperation of the main positioning conical groove and the positioning conical table, most of the radial assembly deviations are eliminated in advance, the incompressible characteristics of hydraulic oil are utilized to drive the elastic material of the positioning hollow cylinder to uniformly expand, the interference fit with the auxiliary positioning groove is formed, the residual radial error is completely compensated, the high-precision coaxial positioning is realized, the annular electromagnet drives the self-adaptive compression plate to abut against the pre-pressing step sidewall, the axial relative movement of the two flanges is constrained, the axial movement after assembly is avoided, and the consistency of the mounting posture of the end executing element is ensured.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of robot end effector connection, in particular to a multi-directional positioning anti-deviation robot arm end flange connection structure. BACKGROUND

[0002] In the field of industrial robot applications, the end effector as the core component directly performing the task, its assembly precision and connection stability with the robot body directly determine the precision, efficiency and safety of the robot work. Whether it is welding, handling, assembly or precision machining scene, the small assembly error between the end effector and the body may be amplified and affect the final work quality, and the high-vibration and high-impact industrial environment further puts forward strict requirements on the reliability of the connection structure. Therefore, the development of an assembly structure with high-precision positioning, strong anti-vibration performance and convenient disassembly characteristics has become one of the important directions of the development of industrial robot technology.

[0003] The traditional robot end effector assembly relies on flange connection to cooperate with locking screws to realize fixation. In order to preliminarily eliminate the radial error, some structures will set a positioning cone surface or a positioning pin on the flange. However, this positioning method has obvious limitations: the cooperation precision of the positioning cone surface is easily affected by the machining error, and only the rough elimination of the radial error can be realized, which is difficult to meet the demand of micron-level assembly precision for precision work; the cooperation of the positioning pin and the pin hole is easy to cause the gap to increase due to wear, and the positioning precision continuously decreases after long-term use. During the screw tightening process, the uneven pressure distribution of the flange surface may also cause local deformation, further aggravate the radial assembly error, and cause the end effector to deviate slightly during work, which affects the key indicators such as welding trajectory precision, handling positioning accuracy, etc. SUMMARY

[0004] The technical problem to be solved by the present application is to overcome the above-mentioned shortcomings of the prior art, and to provide a multi-directional positioning anti-deviation robot arm end flange connection structure with high assembly precision, which can eliminate radial error and axial error.

[0005] The technical scheme adopted to solve the above technical problems is: a first flange connecting assembly is arranged at the end of the robot arm, a second flange connecting assembly is arranged at one end of the robot actuator, the first flange connecting assembly is connected with the second flange connecting assembly to fix and install the robot actuator at the end of the robot arm; the first flange connecting assembly is that a first flange plate is arranged at the end of the robot arm, a plurality of first positioning holes are processed on one side of the first flange plate, each first positioning hole is connected with one side of the second flange connecting assembly through a bolt, a main positioning conical groove is processed in the middle of one side of the first flange plate, and a plurality of positioning hollow cylinders fixedly connected with the second flange connecting assembly are arranged on the main positioning conical groove; the second flange connecting assembly is that a second flange plate is arranged at one end of the robot actuator, a plurality of second positioning holes corresponding to the first positioning holes are processed on one side of the second flange plate, a positioning conical table matched with the main positioning conical groove is arranged in the middle of one side of the second flange plate, and a plurality of auxiliary positioning grooves matched with the positioning hollow cylinders are processed on the positioning conical table.

[0006] Further, each first positioning hole is fixedly connected with the corresponding second positioning hole through a bolt.

[0007] Further, each positioning hollow cylinder is provided with an axial positioning sleeve at one end, each axial positioning sleeve is provided with a through hole penetrating a connecting core column on the side, one end of the connecting core column is provided with a pre-pressing push rod abutting against the bottom of the auxiliary positioning groove, the other end of the connecting core column is provided with a piston slidingly connected with the inside of the positioning hollow cylinder, the inside of the positioning hollow cylinder is filled with hydraulic oil, the circumferential side wall of the positioning hollow cylinder abuts against the circumferential inner side wall of the auxiliary positioning groove, and the positioning hollow cylinder and the piston seal the hydraulic oil.

[0008] Further, the positioning hollow cylinder is composed of a first segment cylinder, a second segment cylinder and a third segment cylinder, the second segment cylinder is located between the first segment cylinder and the third segment cylinder, the first segment cylinder and the third segment cylinder of the positioning hollow cylinder are rigid cylinders, the first segment cylinder is fixedly connected with the main positioning conical groove, the circumferential side wall of the second segment cylinder of the positioning hollow cylinder is made of fluorine rubber elastic material, the third segment cylinder is fixed with the axial positioning sleeve, and the piston is slidingly connected with the inside of the third segment cylinder.

[0009] Further, a sealing ring is arranged between the piston and the positioning hollow cylinder.

[0010] Further, a plurality of through holes are processed in the circumferential direction of the axial positioning sleeve, a self-adapting pressing plate is slidingly connected in each through hole, one side of the self-adapting pressing plate is processed as an inclined surface, and the plurality of self-adapting pressing plates are slidingly out of the corresponding through holes and abut against the side wall of the second flange connecting assembly.

[0011] Further, each of the through holes is provided with a sliding groove on both sides, each of the self-adapting compression plates is provided with a magnetic slider in sliding connection with the sliding groove, and the pre-pressing push rod is provided with an annular electromagnet module in magnetic repulsion with the magnetic slider.

[0012] Further, each of the self-adapting compression plates is movably provided with a flexible non-Newtonian fluid and a friction layer plate, the flexible non-Newtonian fluid is made of flexible and high-strength silicone rubber or polyurethane film, the film is filled with non-Newtonian fluid, the friction layer plate is in friction sliding with the side surface of the axial positioning sleeve, a plurality of sliding grooves for fixedly mounting metal springs are formed in the friction layer plate, the metal springs are located between the flexible non-Newtonian fluid and the friction layer plate, and each of the metal springs is provided with a plurality of protruding blocks in abutment with the flexible non-Newtonian fluid.

[0013] Further, each of the secondary positioning grooves is provided with a pre-pressing step in abutment with the plurality of self-adapting compression plates, and the secondary positioning groove and the pre-pressing step are in communication.

[0014] The beneficial effects of the present application are as follows: (1) the present application eliminates most of the radial assembly deviation in advance through the preliminary centering cooperation of the primary positioning conical groove and the positioning conical step, drives the elastic material of the positioning hollow cylinder to uniformly expand in the radial direction by utilizing the incompressible characteristics of the hydraulic oil, forms an interference fit with the secondary positioning groove, completely compensates for the residual radial error, realizes high-precision coaxial positioning, and the annular electromagnet drives the self-adapting compression plate to abut against the side wall of the pre-pressing step, thereby restraining the axial relative movement of the two flanges, avoiding axial movement after assembly, ensuring the consistency of the installation posture of the end effector, and improving the assembly positioning precision.

[0015] (2) the flexible non-Newtonian fluid is hardened under the action of instantaneous impact force, the protruding blocks on the metal springs cannot extrude the flexible non-Newtonian fluid to deform, therefore, the friction force between the friction layer plate on the self-adapting compression plate and the axial positioning sleeve increases, when the side walls of the plurality of self-adapting compression plates abut against the pre-pressing step, the self-adapting compression plate and the axial positioning sleeve are fixedly locked, the greater the separation force caused by vibration operation, the greater the self-locking force, the generation of axial error is prevented, self-adapting anti-loose is realized, and the self-adapting compression plate is always axially locked on the pre-pressing step, the present embodiment is suitable for high-vibration and high-precision robot operation scenes, and the operation precision and stability of the robot system are significantly improved.

[0016] (3) after the axial pressure is released, the elastic material of the positioning hollow cylinder automatically restores to the original state due to its ultrahigh elasticity, the hydraulic oil pressure disappears to push the piston to reset, no additional unlocking operation is needed, the two flanges can be easily separated, the connecting surface of the two flanges is not damaged, and the labor and time cost required for disassembly and assembly is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a structural schematic diagram of an embodiment of the flange connection structure of the multi-direction positioning anti-deviation robot arm end.

[0018] Figure 2 is a structural schematic diagram of the first flange connection assembly.

[0019] Figure 3 is a structural schematic diagram of the positioning hollow cylinder.

[0020] Figure 4 is a structural schematic diagram of the inside of the positioning hollow cylinder.

[0021] Figure 5 is a structural schematic diagram of the axial positioning sleeve.

[0022] Figure 6 is a structural schematic diagram of the self-adaptive compression plate, sealing ring, and piston.

[0023] Figure 7 is a structural schematic diagram of the self-adaptive compression plate.

[0024] Figure 8 is a structural schematic diagram of the friction layer plate, flexible non-Newtonian fluid, and metal spring.

[0025] Figure 9 is an exploded view of Figure 8 .

[0026] Figure 10 is a structural schematic diagram of the second flange connection assembly.

[0027] Figure 11 is a structural schematic diagram of the inside of the second flange plate.

[0028] Reference signs: 1, robot arm; 2, first flange connection assembly; 201, first flange plate; 202, main positioning conical groove; 203, first positioning hole; 204, positioning hollow cylinder; 205, self-adaptive compression plate; 206, axial positioning sleeve; 207, pre-pressing push rod; 208, sealing ring; 209, piston; 210, annular electromagnet module; 211, hydraulic oil; 212, through hole; 213, sliding groove; 214, through hole; 215, connecting core column; 216, friction layer plate; 217, magnetic sliding block; 218, flexible non-Newtonian fluid; 219, metal spring; 220, protruding block; 221, sliding groove; 3, second flange connection assembly; 301, auxiliary positioning groove; 302, positioning conical table; 303, second positioning hole; 304, second flange plate; 305, pre-pressing step; 4, robot execution component. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below with reference to the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and not to limit the present application.

[0030] As shown in Figure 1 , the multi-direction positioning anti-deviation robot arm end flange connection structure of the embodiment is composed of a robot arm 1, a first flange connection assembly 2, a second flange connection assembly 3, and a robot execution member 4.

[0031] The robot arm 1 is provided at the end with the first flange connection assembly 2, and the robot execution member 4 is provided at one end with the second flange connection assembly 3, and the first flange connection assembly 2 is connected with the second flange connection assembly 3 for fixing and installing the robot execution member 4 at the end of the robot arm 1.

[0032] As shown in Figures 2 to 9 , the first flange connection assembly 2 is composed of a first flange plate 201, a main positioning conical groove 202, a first positioning hole 203, a positioning hollow cylinder 204, a self-adapting compression plate 205, an axial positioning sleeve 206, a pre-pressing push rod 207, a sealing ring 208, a piston 209, a ring-shaped electromagnetic module 210, hydraulic oil 211, a through hole 212, a sliding groove 213, a through hole 214, a connecting core column 215, a friction layer plate 216, a magnetic sliding block 217, a flexible non-Newtonian fluid 218, a metal spring 219, a protruding block 220, and a sliding groove 221.

[0033] The first flange connection assembly 2 is that the robot arm 1 is provided at the end with the first flange plate 201, a plurality of first positioning holes 203 are machined on one side of the first flange plate 201, each first positioning hole 203 is connected with one side of the second flange connection assembly 3 through a bolt, a main positioning conical groove 202 is machined in the middle of one side of the first flange plate 201, and a plurality of positioning hollow cylinders 204 are arranged on the main positioning conical groove 202 and fixedly clamped with the second flange connection assembly 3.

[0034] As shown in Figures 3 to 4 , each positioning hollow cylinder 204 is provided at one end with an axial positioning sleeve 206, each axial positioning sleeve 206 is provided at the side with a through hole 214 penetrating the connecting core column 215, one end of the connecting core column 215 is provided with a pre-pressing push rod 207 abutting against the bottom of the auxiliary positioning groove 301, the other end of the connecting core column 215 is provided with a piston 209 slidingly connected with the inside of the positioning hollow cylinder 204, the inside of the positioning hollow cylinder 204 is filled with hydraulic oil 211, the circumferential side wall of the positioning hollow cylinder 204 abuts against the circumferential inner side wall of the auxiliary positioning groove 301, the positioning hollow cylinder 204 and the piston 209 seal the hydraulic oil 211, and the sealing ring 208 is arranged between the piston 209 and the positioning hollow cylinder 204.

[0035] The positioning hollow cylinder 204 is composed of a first section cylinder, a second section cylinder and a third section cylinder, the second section cylinder is located between the first section cylinder and the third section cylinder, the first section cylinder and the third section cylinder of the positioning hollow cylinder 204 are rigid cylinders, the first section cylinder is fixedly connected with the main positioning conical groove 202, the second section cylinder of the positioning hollow cylinder 204 is made of fluorine rubber or hydrogenated butyronitrile rubber, the third section cylinder is fixed with the axial positioning sleeve 206, and the piston 209 is slidably connected with the inside of the third section cylinder.

[0036] As shown in Figure 5 The axial positioning sleeve 206 is provided with a plurality of through holes 212 in the circumferential direction, and each through hole 212 is slidably connected with an adaptive compression plate 205. One side of the adaptive compression plate 205 is processed as an inclined surface, and a plurality of adaptive compression plates 205 are respectively slid out of the corresponding through holes 212 and abut against the side wall of the second flange connecting assembly 3. The inside of each through hole 212 is respectively provided with a sliding groove 213 on both sides, and each adaptive compression plate 205 is respectively provided with a magnetic sliding block 217 which is slidably connected with the sliding groove 213. The pre-pressing push rod 207 is provided with an annular electromagnetic iron module 210 which is magnetically repulsive with the magnetic sliding block 217.

[0037] As shown in Figures 7 to 9 Each adaptive compression plate 205 is respectively provided with a flexible non-Newtonian fluid 218 and a friction layer plate 216. The flexible non-Newtonian fluid 218 is made of flexible and high-strength silicone rubber or polyurethane film, the inside of the film is filled with non-Newtonian fluid, the friction layer plate 216 is frictionally and slidably connected with the side surface of the axial positioning sleeve 206, the friction layer plate 216 is provided with a plurality of sliding grooves 221 for fixedly mounting metal spring sheets 219, the metal spring sheets 219 are located between the flexible non-Newtonian fluid 218 and the friction layer plate 216, and each metal spring sheet 219 is respectively provided with a plurality of protruding blocks 220 which abut against the flexible non-Newtonian fluid 218.

[0038] As shown in Figures 10 to 11 The second flange connecting assembly 3 is composed of a sub-positioning groove 301, a positioning conical table 302, a second positioning hole 303, a second flange plate 304 and a pre-pressing step 305.

[0039] The second flange connection assembly 3 is that the robot executor 4 is provided with a second flange plate 304 at one end, a plurality of second positioning holes 303 corresponding to the first positioning holes 203 are processed on one side of the second flange plate 304, and each first positioning hole 203 is fixedly connected with the corresponding second positioning hole 303 through a bolt. A positioning conical table 302 matched with the main positioning conical groove 202 is arranged in the middle of one side of the second flange plate 304, and a plurality of auxiliary positioning grooves 301 matched with the positioning hollow cylinder 204 are processed on the positioning conical table 302. A pre-pressing step 305 matched with the plurality of self-adaptive compression plates 205 is arranged at the bottom of each auxiliary positioning groove 301, and the auxiliary positioning groove 301 and the pre-pressing step 305 are in communication with each other.

[0040] The working principle of the embodiment is as follows: when the robot executor 4 is assembled on the robot arm 1, the first flange connection assembly 2 on the robot arm 1 is aligned through the second flange connection assembly 3 on the robot executor 4, the main positioning conical groove 202 on the first flange plate 201 is matched with the positioning conical table 302 on the second flange plate 304, and the radial error can be preliminarily eliminated. The first positioning hole 203 on the first flange plate 201 is fixedly connected with the second positioning hole 303 on the corresponding second flange plate 304 through a bolt, and the main positioning conical groove 202 on the first flange plate 201 is matched with the positioning conical table 302 on the second flange plate 304 to the final position during the locking process of the first flange plate 201 and the second flange plate 304.

[0041] With the bolt in the fixing process, the pre-pressing push rod 207 is in contact with the inner bottom of the pre-pressing step 305, the pre-pressing push rod 207 drives the piston 209 to slide in the positioning hollow cylinder 204 through the connecting core column 215. Because the hydraulic oil 211 in the positioning hollow cylinder 204 has the characteristic of being incompressible, the internal pressure of the positioning hollow cylinder 204 gradually rises, and the pressure generated is uniformly applied to the inner wall of the positioning hollow cylinder 204. The second segment of the positioning hollow cylinder 204 is made of fluororubber or hydrogenated nitrile rubber elastic material, so that it can produce accurate and uniform elastic expansion in the radial direction. The positioning hollow cylinder 204 and the side wall of the auxiliary positioning groove 301 form an interference fit, which can eliminate the radial error of the first flange connection assembly 2 and the second flange connection assembly 3 during assembly, effectively avoid the problem of work precision decline of the end effector caused by radial deviation, and provide reliable protection for precision welding and precise handling. When the axial pressure is removed, the pressure of the compressed hydraulic oil 211 disappears, and the ultra-high elasticity of the fluororubber or hydrogenated nitrile rubber elastic material itself can automatically restore to the original state. The rebound force in the recovery process is enough to push the piston 209 back to the initial position, and the diameter of the positioning hollow cylinder 204 returns to the original state, so that the assembly can be easily disassembled.

[0042] After the bolt is screwed through the first flange plate 201 and the second flange plate 304, the annular electromagnet module 210 is started, the annular electromagnet module 210 exerts a repulsive magnetic field on the plurality of adaptive compression plates 205, so that each adaptive compression plate 205 is respectively slid out in the through hole 212, while the magnetic sliders 217 on both sides of the adaptive compression plate 205 are respectively slid in the sliding groove 213 of the through hole 212, the plurality of adaptive compression plates 205 are respectively in contact with the side wall of the pre-pressing step 305, preventing a large axial error between the first flange plate 201 and the second flange plate 304.

[0043] During the work process of the robot implement 4 on the robot arm 1, high vibration may occur, the friction layer plate 216 on the adaptive compression plate 205 has friction force with one side of the axial positioning sleeve 206 during the sliding-out process, and the vibration force generated during the work process of the robot implement 4 generates intermittent impact force on the flexible non-Newtonian fluid 218, at this time, the impact force has the characteristics of short action time and high instantaneous stress, and the impact on the flexible non-Newtonian fluid 218 will cause it to "harden", at this time, the convex block 220 on the metal spring piece 219 cannot extrude the flexible non-Newtonian fluid 218 to cause it to deform, so the friction force between the friction layer plate 216 on the adaptive compression plate 205 and the axial positioning sleeve 206 will increase, when the plurality of adaptive compression plates 205 are respectively in contact with the side wall of the pre-pressing step 305, the adaptive compression plate 205 and the axial positioning sleeve 206 are fixedly locked, the greater the separation force caused by the vibration operation process, the greater the self-locking force, the adaptive anti-loose is realized, and it is ensured that the adaptive compression plate 205 always completes the axial locking on the pre-pressing step 305.

[0044] The radial expansion of the positioning hollow cylinder 204 and the axial compression effect of the adaptive compression plate 205 can ensure the assembly precision between the first flange plate 201 and the second flange plate 304, eliminate assembly errors, and maintain excellent stability during the operation process.

[0045] The above only describes the preferred embodiments of the present application and is not used to limit the protection scope of the present application.

Claims

1. A multi-directional positioning anti-drift robot arm end flange connection structure, characterized in that: The robot arm (1) is provided with a first flange connection assembly (2) at the end, a robot execution element (4) is provided with a second flange connection assembly (3) at one end, and the first flange connection assembly (2) is connected with the second flange connection assembly (3) for fixing and installing the robot execution element (4) at the end of the robot arm (1); The first flange connection assembly (2) is that the robot arm (1) is provided with a first flange plate (201) at the end, a plurality of first positioning holes (203) are processed on one side of the first flange plate (201), each first positioning hole (203) is connected with one side of the second flange connection assembly (3) through a bolt, a main positioning conical groove (202) is processed in the middle of one side of the first flange plate (201), and a plurality of positioning hollow cylinders (204) are arranged on the main positioning conical groove (202) and fixedly connected with the second flange connection assembly (3); Each positioning hollow cylinder (204) is provided with an axial positioning sleeve (206) at one end, each axial positioning sleeve (206) is provided with a through hole (214) penetrating a connecting core column (215) on the side, one end of the connecting core column (215) is provided with a pre-pressing push rod (207) abutting against the bottom of the auxiliary positioning groove (301), the other end of the connecting core column (215) is provided with a piston (209) slidingly connected with the inside of the positioning hollow cylinder (204), the inside of the positioning hollow cylinder (204) is filled with hydraulic oil (211), the circumferential side wall of the positioning hollow cylinder (204) abuts against the circumferential inner side wall of the auxiliary positioning groove (301), and the positioning hollow cylinder (204) and the piston (209) seal the hydraulic oil (211); The positioning hollow cylinder (204) is composed of a first segment cylinder, a second segment cylinder and a third segment cylinder, the second segment cylinder is located between the first segment cylinder and the third segment cylinder, the first segment cylinder and the third segment cylinder of the positioning hollow cylinder (204) are rigid cylinders, the first segment cylinder is fixedly connected with the main positioning conical groove (202), the circumferential side wall of the second segment cylinder of the positioning hollow cylinder (204) is made of fluorine rubber elastic material, the third segment cylinder is fixed with the axial positioning sleeve (206), and the piston (209) is slidingly connected with the inside of the third segment cylinder; The axial positioning sleeve (206) is provided with a plurality of through holes (212) in the circumferential direction, each through hole (212) is slidingly connected with a self-adapting pressing plate (205) in the inside, one side of the self-adapting pressing plate (205) is processed as an inclined surface, and a plurality of self-adapting pressing plates (205) are respectively slid out of the corresponding through holes (212) and abut against the side wall of the second flange connection assembly (3). Each adaptive compression plate (205) is movably provided with a flexible non-Newtonian fluid (218) and a friction layer plate (216), the flexible non-Newtonian fluid (218) is made of flexible and high-strength silicone rubber or polyurethane film, the film is filled with non-Newtonian fluid, the friction layer plate (216) is in friction sliding with the side surface of the axial positioning sleeve (206), the friction layer plate (216) is processed with a plurality of sliding grooves (221) for fixedly mounting metal springs (219), the metal springs (219) are located between the flexible non-Newtonian fluid (218) and the friction layer plate (216), each metal spring (219) is respectively provided with a plurality of protruding blocks (220) in abutment with the flexible non-Newtonian fluid (218); The second flange connecting assembly (3) is characterized in that: one end of the robot executive part (4) is provided with a second flange plate (304), a plurality of second positioning holes (303) corresponding to the first positioning holes (203) are processed on one side of the second flange plate (304), a positioning conical table (302) matched with the main positioning conical groove (202) is arranged on one side of the second flange plate (304), and a plurality of auxiliary positioning grooves (301) matched with the positioning hollow cylinder (204) are processed on the positioning conical table (302).

2. The multi-directional positioning anti-drift robot arm end flange connection structure according to claim 1, characterized in that: Each first positioning hole (203) is fixedly connected with the corresponding second positioning hole (303) through a bolt.

3. The multi-directional positioning anti-drift robot arm end flange connection structure according to claim 1, characterized in that: The piston (209) and the positioning hollow cylinder (204) are provided with a sealing ring (208) therebetween.

4. The multi-directional positioning anti-drift robot arm end flange connection structure according to claim 1, characterized in that: Both sides of each through hole (212) are respectively processed with a sliding groove (213), both sides of each adaptive compression plate (205) are respectively provided with a magnetic sliding block (217) in sliding connection with the sliding groove (213), and the pre-pressing push rod (207) is provided with an annular electromagnetic iron module (210) in magnetic repulsion with the magnetic sliding block (217).

5. The multi-directional positioning anti-drift robot arm end flange connection structure according to claim 1, characterized in that: The bottom of each auxiliary positioning groove (301) is respectively provided with a pre-pressing step (305) in abutment with the plurality of adaptive compression plates (205), and the auxiliary positioning groove (301) and the pre-pressing step (305) are in communication with each other.

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