High compression ratio reducing mechanism, pipe robot and linear reducing method

Abstract

The application discloses a high-compression-ratio variable-diameter mechanism, which comprises a static support, an executing mechanism, a dynamic support and a driving assembly; the static support and the dynamic support are installed in parallel on a main body and are fixed, and the dynamic support can move in a transverse direction under the action of the driving assembly and move towards or away from the static support; the executing mechanism is arranged between the static support and the dynamic support; when the driving assembly drives the dynamic support to move towards the static support, the executing mechanism is elongated; and when the driving assembly drives the dynamic support to move away from the static support, the executing mechanism is shortened; the application has good adaptability to changes in the diameter of a pipeline and improves the practicability of a pipeline robot in a complex environment.

Description

Technical Field

[0001] This invention belongs to the field of pipeline robot technology, specifically relating to a high compression ratio diameter changing mechanism, a pipeline robot, and a linear diameter changing method. Background Technology

[0002] Pipeline robots are used for pipeline condition assessment, leak detection, and fluid quality monitoring. To improve the driving force of pipeline robots, most are equipped with several (usually 2-4) moving devices arranged radially. When the pipeline robot moves through a circular pipe, the moving devices contact the inner wall of the pipe, using the friction of the inner wall to propel the robot forward. A diameter-adjusting mechanism can be installed between the moving devices and the main body of the pipeline robot to drive the moving devices to open or close, adapting to pipes of different diameters.

[0003] There are two types of diameter-changing mechanisms: passive and active. CN115306984A discloses a passive diameter-changing mechanism. (See appendix) Figure 1 When the pipe diameter changes, the spring is compressed, and the diameter of the pipe-changing mechanism adapts accordingly, thus enabling the pipe robot to change diameter. Publication number [CN113357481A] discloses an active diameter-changing mechanism; see appendix. Figure 2 The variable diameter drive motor rotates the lead screw 012, and the cooperating lead screw nut 013 feeds axially, driving the spring support rod 006. The spring support rod 006 is connected to the walking mechanism through the linkage group 014, thereby pushing the walking mechanism to extend radially, realizing the diameter change of the pipeline robot. Patent publication number [CN115370868A] discloses another active diameter changing mechanism. See appendix. Figure 3 The deformable drive motor 405 drives the worm gear 404 to rotate. The worm gear 404 meshes with the worm wheel 403, which is coaxial with and rotates synchronously with the gear 402. One turntable is fixedly connected to the housing, while the other turntable 101 is rotatably engaged with the housing. The gear 402 meshes with the arc-shaped rack 102 on the rotatable turntable. By rotating the deformable drive motor 405, the rotatable turntable 101 is driven to rotate, causing the walking wheel assembly 300 to open or retract, thus realizing the diameter change of the pipeline robot.

[0004] However, the compression ratio of the existing active variable-diameter mechanism and passive variable-diameter mechanism is small. The compression ratio of the passive variable-diameter mechanism ranges from 1.0 to 1.1. In the pipeline with large diameter change, it is difficult for the pipeline robot to ensure the contact with the pipe wall, resulting in the difficulty of the pipeline robot in climbing the vertical pipeline and maintaining the posture, and it is difficult to meet the demand of the complex pipeline working environment. The compression ratio of the active variable-diameter mechanism ranges from 1.1 to 1.4. Not only the compression ratio is small, but also the active variable-diameter mechanism is restricted by the structural characteristics of the screw, fork frame and other mechanisms. The motor output torque mode is single and presents significant nonlinear characteristics, which is not conducive to the variable-diameter control and the analysis of the normal pressure between the robot and the inner wall of the pipeline. SUMMARY

[0005] Therefore, the application provides a high-compression-ratio variable-diameter mechanism, a pipeline robot and a linear variable-diameter method.

[0006] The application is realized by the following technical solutions.

[0007] The high-compression-ratio variable-diameter mechanism is part of the pipeline robot, and the pipeline robot further comprises a main body located at the center and a plurality of walking mechanisms located at the periphery of the main body. The variable-diameter mechanism is installed between the main body and the walking mechanisms and is used to realize the variable-diameter of the pipeline robot.

[0008] The variable-diameter mechanism comprises a static support, an executing mechanism, a dynamic support and a driving assembly.

[0009] The axial direction of the pipeline robot is the transverse direction, and the radial direction of the pipeline robot is the longitudinal direction.

[0010] The static support and the dynamic support are installed side by side and parallel to each other on the main body, and the static support is fixed, and the dynamic support can move in the transverse direction under the action of the driving assembly and move towards or away from the static support.

[0011] The executing mechanism is arranged between the static support and the dynamic support. The executing mechanism comprises a multi-link telescopic arm, a bottom support and a walking mechanism connecting block.

[0012] One end of the multi-link telescopic arm is slidably connected to the bottom support, and the other end is connected to the walking mechanism through the walking mechanism connecting block. The multi-link telescopic arm can move longitudinally.

[0013] When the driving assembly drives the dynamic support to move towards the static support, the multi-link telescopic arm is compressed in the transverse direction, the length of the multi-link telescopic arm is elongated, and the bottom support is extended in the longitudinal direction.

[0014] When the driving element drives the dynamic support to move away from the static support, the multi-link telescopic arm is stretched laterally, the length of the multi-link telescopic arm is shortened, and the bottom support is contracted longitudinally.

[0015] Further, the variable-diameter mechanism further comprises an actuator guide, the bottom support is provided with a guide boss, the actuator guide is provided with a guide groove, and the guide boss and the guide groove are matched;

[0016] When the driving assembly drives the dynamic support to move towards the static support, the bottom support is extended longitudinally along the guide groove;

[0017] When the driving element drives the dynamic support to move away from the static support, the bottom support is contracted longitudinally along the guide groove.

[0018] Further, the driving assembly comprises a driving element, a ball screw nut and a ball screw;

[0019] The two ends of the main body are respectively an M end and an N end, the driving element is fixedly arranged at the M end in the main body, the ball screw is arranged in the main body, one end of the ball screw is fixedly connected with the output end of the driving element, and the other end is connected with the N end of the main body through a rotary pair; the static support is fixedly connected with the main body; the dynamic support is fixedly connected with the ball screw nut on the ball screw; one end of the bottom support of the actuator is connected with the static support, and the other end is connected with the main body through the dynamic support;

[0020] The static support is fixed relative to the main body, the output end of the driving element rotates to drive the ball screw to rotate synchronously, the dynamic support moves along the ball screw with the ball screw nut in a reciprocating linear manner, and the relative moving or moving away of the static support and the dynamic support is realized.

[0021] Further, the actuator further comprises a telescopic arm lateral slider, two groups of telescopic arm longitudinal guide rods, three groups of bottom support longitudinal sliders and bottom support longitudinal guide rods;

[0022] One group of telescopic arm longitudinal guide rods is fixedly installed on the static support in the longitudinal direction; the other group of telescopic arm longitudinal guide rods is fixedly installed on the dynamic support in the longitudinal direction; and the bottom support longitudinal guide rod is fixed on the main body in the longitudinal direction;

[0023] The first group of bottom support longitudinal sliders is located at one end of the bottom support and is slidably connected with the telescopic arm longitudinal guide rod on the static support;

[0024] The third group of bottom support longitudinal sliders is located at the other end of the bottom support and is slidably connected with the bottom support longitudinal guide rod on the main body;

[0025] The telescopic arm lateral slider is arranged on the bottom support and can move reciprocatingly in the lateral direction of the bottom support; the second group of bottom support longitudinal sliders is arranged on the telescopic arm lateral slider and is slidably connected with the telescopic arm longitudinal guide rod on the dynamic support;

[0026] The multi-link telescopic arm is composed of two or more multi-link telescopic frames, and the longitudinal ends of each multi-link telescopic frame are respectively P end and Q end, the P end is connected with the bottom support, the Q end is connected with the walking mechanism connecting block, the P end has two pin joints, one pin joint is connected with the end of the static support of the bottom support, the other pin joint is connected with the telescopic arm transverse sliding block, the Q end has two pin joints, one pin joint is connected with one end of the walking mechanism connecting block, a transverse sliding groove is arranged on the walking mechanism connecting block, a sliding pin is arranged in the sliding groove, and the other pin joint of the Q end is connected with the end of the sliding pin.

[0027] Further, the actuator further comprises two groups of telescopic arm longitudinal sliding blocks, one group of telescopic arm longitudinal sliding blocks is slidably arranged on the telescopic arm longitudinal guide rod on the static support and is located above the first group of bottom support longitudinal sliding blocks, and the other group of telescopic arm longitudinal sliding blocks is slidably arranged on the telescopic arm longitudinal guide rod on the dynamic support and is located above the second group of bottom support longitudinal sliding blocks; the pin joints located in the longitudinal middle part of the multi-link telescopic frame and at the two ends of the transverse direction are respectively and correspondingly connected with the two groups of telescopic arm longitudinal sliding blocks.

[0028] Further, the actuator guide is a guide disc, the guide disc is a disc structure, the guide disc is provided with a central hole, the guide disc is matched with the ball screw hole shaft through the central hole and is located between the static support and the N end of the main body, the guide disc can rotate with the ball screw, the guide groove is guide groove I, the guide groove I is arranged on one surface of the guide disc and is arc-shaped, the guide grooves I which are the same in number as the actuator are centrally symmetrically distributed with the central hole as the center, the two ends of the guide groove I are A end and E end, the distance from the A end of the guide groove I to the center is less than the distance from the E end of the guide groove I to the center.

[0029] The guide boss of each actuator is arranged at the end of the end of the static support of the bottom support, the guide boss can slide along the corresponding guide groove I, when the guide boss is located at the A end of the guide groove I, the bottom support is located at the limit position I, corresponding to the minimum diameter of the variable diameter mechanism, when the guide boss is located at the D end of the guide groove I, the bottom support is located at the limit position II, corresponding to the maximum diameter of the variable diameter mechanism.

[0030] Further, the actuator guide further comprises a harmonic reducer, the harmonic reducer is arranged in the N end of the main body, the harmonic reducer comprises a steel wheel, a flexible wheel and a wave generator, the wave generator is coaxially arranged in the inner circumference of the flexible wheel, and the steel wheel is coaxially arranged on the outer circumference of the flexible wheel; the steel wheel is fixedly arranged in the N end of the main body, the ball screw is fixedly connected with the wave generator at one end of the N end of the main body, and the flexible wheel is fixedly connected with the guide disc.

[0031] Further, the guide boss is arranged on the outside of the length direction of the bottom support, the guide boss is two groups, one group is arranged on the end of the static support, and the other group is fixed opposite to the telescopic arm transverse sliding block.

[0032] The actuator guide is a guide groove member, the guide groove member is a plate type structure, and the plate type structure is arranged outside the length direction of the bottom support; the end where the static support of the guide groove member is located is provided with a vertical guide groove in the longitudinal direction, and the guide boss at the end of the static support is located in the vertical guide groove and can move longitudinally along the vertical guide groove; the end where the dynamic support of the guide groove member is located is provided with an inclined guide groove, and the guide boss fixed opposite to the horizontal sliding block of the telescopic arm is located in the inclined guide groove; when the dynamic support moves towards the static support, the bottom support extends under the action of the inclined guide groove while the multi-link telescopic arm is compressed horizontally; the bottom support retracts while the multi-link telescopic arm is stretched horizontally.

[0033] A pipeline robot comprises the variable-diameter mechanism, a main body and a walking mechanism; the number of actuators in the variable-diameter mechanism is two or more, and the actuators are arranged in a radial manner on the outer circumference of the main body.

[0034] The walking mechanism is fixedly connected to the end of the actuator.

[0035] Each walking mechanism comprises a mounting seat, a driving wheel and a load wheel.

[0036] The mounting seat is connected to the end of the actuator, the driving wheel and the load wheel are arranged side by side in the mounting seat and along the length direction of the main body; the middle part of the driving wheel and the load wheel is cylindrical, and the outer part of the driving wheel and the load wheel is provided with a track together, which is used to contact the inner wall of the pipeline.

[0037] A linear variable-diameter method of a high-compression-ratio variable-diameter mechanism, based on the high-compression-ratio variable-diameter mechanism;

[0038] The design of the theoretical profile of the guide groove I of the guide disc makes the longitudinal length of the variable-diameter mechanism and the movement length of the dynamic support along the ball screw in a linear relationship.

[0039] The design method of the theoretical profile is as follows:

[0040] Step S1: determining the change trend of the lifting height of the bottom support with the movement length of the screw nut on the ball screw, so as to determine the trajectory trend of the theoretical profile;

[0041] Step S2: based on the trajectory trend of the theoretical profile, determining the maximum value of the lifting height of the bottom support according to the constraint condition I of the theoretical profile ;

[0042] The constraint condition I is that: in order to ensure that each component does not interfere and the strength meets the demand, the limit minimum distance of any point on each theoretical profile from the center of the guide disc is ;

[0043] Step S3, based on the maximum value of the lifting height of the bottom support obtained in step S2 , obtain the function of the lifting height of the bottom support , and convert the profile equation of the theoretical profile line again , and determine the maximum central angle of the terminal point E and the starting point A of the theoretical profile line according to the constraint condition II of the theoretical profile line ;

[0044] wherein the constraint condition II is that the minimum limit distance between every two adjacent theoretical profile lines is ;

[0045] The theoretical profile line designed through steps S1-S3 can realize the linear relationship between the longitudinal length of the variable diameter mechanism and the movement length of the movable support along the ball screw.

[0046] Advantages:

[0047] (1) The present application utilizes the opposite or away movement of the static support and the movable support, simultaneously realizes the elongation or shortening of the multi-link telescopic arm itself and the extension or contraction of the whole actuator, can increase the space utilization rate under the limited size, increase the variable diameter range and compression ratio, the maximum compression ratio can reach 1.7 through theoretical calculation and actual verification, has good pipeline diameter change adaptability, and greatly improves the practicability of the pipeline robot in complex environment.

[0048] (2) The present application utilizes the cooperation of the driving assembly, the ball screw and the screw nut, can realize the linear input of the movable support, makes the displacement of the movable support proportional to the output rotation speed of the driving element, and is convenient for the control of the movable support.

[0049] (3) The present application realizes the longitudinal guidance of the bottom support and the transverse guidance of the multi-link telescopic frame through the setting of the telescopic arm transverse sliding block, the two groups of telescopic arm longitudinal guide rods and the bottom support longitudinal guide rod, guarantees the stability and strength of the longitudinal movement of the multi-link telescopic arm and the bottom support.

[0050] (4) The present application realizes the longitudinal guidance of the multi-link telescopic arm through the cooperation of the two groups of telescopic arm longitudinal sliding blocks and the telescopic arm longitudinal guide rods, further guarantees the telescopic stability and support strength of the multi-link telescopic arm.

[0051] (5) The actuator guide of the present application is a guide disc, the guide groove is guide groove I, through the cooperation of the guide boss and the guide disc, along with the rotation of the guide disc, the guide boss moves along the guide groove I, and since the distance from the C end of the guide groove I to the center is less than the distance from the other end D to the center, the bottom support approaches or moves away from the ball screw along with the guide boss, and the longitudinal movement of the bottom support is realized.

[0052] (6) The actuator guide of the present application can further comprise a harmonic reducer to realize rate control of the bottom support telescopic movement, guarantee telescopic control precision and telescopic reliability.

[0053] (7) The actuator guide of the present application can be a guide groove component, through the setting of vertical guide grooves and inclined guide grooves, realizing longitudinal movement of the bottom support and realizing variable diameter of the variable diameter mechanism.

[0054] (8) The present application provides a pipeline robot, the walking mechanism includes driving wheel and heavy wheel, the driving wheel is used to drive and bear pressure, the heavy wheel is only used to bear pressure, and the outside of the driving wheel and the heavy wheel is provided with a track in common, which improves the pressure bearing capacity of the walking mechanism, and realizes the movement of the pipeline robot in the pipeline.

[0055] (9) The present application can overcome the nonlinear change characteristics of the multi-link telescopic arm itself by designing the theoretical profile curve equation of the guide disc , facilitate linear control of the telescopic variable diameter mechanism and normal pressure analysis between the robot and the inner wall of the pipeline; under the constraint condition II, the present application determines the maximum central angle of the terminal point E and the starting point A of the theoretical profile , on the one hand, from the torque angle of the guide disc, The larger it is, the flatter the theoretical profile is, the smaller the pressure angle is, and in the case of a certain radial force, the tangential force is smaller, the guide disc shaft torque is smaller, which is beneficial to reduce the load; on the other hand, The larger it is, the smaller the transmission ratio of the ball screw and the guide disc is, which is beneficial to reduce the reducer mass and reduce. And, it can ensure that there is no interference between components and the overall movement is not distorted, and ensure the strength of the variable diameter mechanism. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 It is a kind of existing passive variable diameter mechanism;

[0057] Figure 2 It is a kind of existing active variable diameter mechanism I;

[0058] Figure 3 It is a kind of existing active variable diameter mechanism II;

[0059] Figure 4 It is the installation schematic diagram of the variable diameter mechanism of the present application on the pipeline robot;

[0060] Figure 5 It is the sectional view of the variable diameter mechanism of the present application;

[0061] Figure 6 It is the schematic diagram of the variable diameter actuator of the present application;

[0062] Figure 7 It is the sectional view of the variable diameter mechanism of the present application;

[0063] Figure 8 is the schematic diagram of the guide disc of the present application;

[0064] Figure 9 is the schematic diagram of the guide disc installation of the present application;

[0065] Figure 10 is the schematic diagram of the connection relationship of the harmonic reducer of the present application Figure I ;

[0066] Figure 11 is the schematic diagram of the connection relationship of the harmonic reducer of the present application Figure II

[0067] Figure 12 is the schematic diagram of the guide groove component of the present application;

[0068] Figure 13 is the plan view of the pipeline robot of the present application;

[0069] Figure 14 is the perspective view of the pipeline robot of the present application;

[0070] Figure 15 is the simplified diagram of the variable-diameter mechanism of the present application

[0071] Figure 16 is the curve diagram of the moving length of the guide disc-ball screw

[0072] Figure 17 is the schematic diagram of the space occupied by the theoretical profile of the present application;

[0073] Among them, 006 is a spring support rod, 012 is a screw, 013 is a nut holder, and 014 is a connecting rod set.

[0074] 101 is a rotating disc, 102 is an arc-shaped rack, 300 is a walking wheel assembly, 402 is a gear, 403 is a worm wheel, 404 is a driving worm, and 405 is a deformation driving motor.

[0075] 1 is a static support, 2 is a main body, 3 is an actuating mechanism, 30 is a telescopic arm transverse sliding block, 31 is a guide boss, 32 is a bottom support, 33 is a telescopic arm longitudinal guide rod, 34 is a telescopic arm longitudinal sliding block, 35 is a connecting rod, 36 is a walking mechanism connecting block, 37 is a multi-link telescopic arm, 38 is a bottom support longitudinal guide rod, 39 is a bottom support longitudinal sliding block, 4 is a driving element, 5 is a screw nut, 6 is a dynamic support, 7 is a ball screw, 81 is a guide disc, 811 is a guide groove I, 812 is a center hole, 813 is a harmonic reducer, 82 is a guide groove component, 821 is a vertical guide groove, 822 is an inclined guide groove, 9 is a walking mechanism, 91 is a driving wheel, 92 is a load wheel, 93 is a mounting seat, 94 is a track, and 95 is a transition wheel. DETAILED DESCRIPTION

[0076] The application will be described in detail below with reference to the drawings and embodiments.

[0077] Embodiment 1

[0078] The embodiment provides a high compression ratio variable diameter mechanism, which is used as a part of a pipeline robot, the pipeline robot further comprises a central main body 2 and a plurality of walking mechanisms 9 located at the periphery of the main body, and the variable diameter mechanism is installed between the main body 2 and the walking mechanisms 9 and used for realizing variable diameter of the pipeline robot.

[0079] The high compression ratio variable diameter mechanism comprises a static support 1, an executing mechanism 3, a dynamic support 6 and a driving assembly.

[0080] The axial direction of the pipeline robot is the transverse direction, and the radial direction of the pipeline robot is the longitudinal direction.

[0081] The static support 1 and the dynamic support 6 are installed side by side and parallel to each other on the main body 2, and the static support 1 is fixed, and the dynamic support 6 can move in the transverse direction under the action of the driving assembly and move towards or away from the static support 1.

[0082] The executing mechanism 3 is arranged between the static support 1 and the dynamic support 6, and the executing mechanism 3 comprises a multi-link telescopic arm 37, a bottom support 32 and a walking mechanism connecting block 36. Figure 5 The multi-link telescopic arm 37 is slidably connected to the bottom support 32 at one end and slidably connected to the walking mechanism connecting block 36 at the other end.

[0083] When the driving assembly drives the dynamic support 6 to move towards the static support 1, the multi-link telescopic arm 37 is compressed in the transverse direction, the length of the multi-link telescopic arm 37 is elongated, and the bottom support 32 is extended in the longitudinal direction, so that the variable diameter mechanism is elongated.

[0084] When the driving assembly drives the dynamic support 6 to move away from the static support 1, the multi-link telescopic arm 37 is stretched in the transverse direction, the length of the multi-link telescopic arm 37 is shortened, and the bottom support 32 is retracted in the longitudinal direction, so that the variable diameter mechanism is shortened.

[0085] The embodiment simultaneously realizes elongation or shortening of the multi-link telescopic arm 37 and extension or retraction of the bottom support 32 by using the towards or away movement of the static support 1 and the dynamic support 6, so that the space utilization can be increased in a limited size, the variable diameter range and the compression ratio are increased, the maximum compression ratio can reach 1.7 according to theoretical calculation and actual verification, the pipeline robot has good pipeline diameter change adaptability, and the practicability of the pipeline robot in a complex environment is greatly improved.

[0086]

[0087] ​The high compression ratio variable diameter mechanism further comprises an actuator guide, the bottom support 32 is provided with a guide boss 31, the actuator guide is provided with a guide groove, and the guide boss 31 cooperates with the guide groove; when the driving assembly drives the moving support 6 to move towards the static support 1, the bottom support 32 extends along the longitudinal direction with the guide groove; when the driving assembly drives the moving support 6 to move away from the static support 1, the bottom support 32 retracts along the longitudinal direction with the guide groove, so that the extension and retraction of the bottom support 32 is realized.

[0088] The driving assembly comprises a driving element 4, a screw nut 5 and a ball screw 7;

[0089] The two ends of the main body 2 are respectively an M end and an N end, the driving element 4 is fixedly arranged in the M end of the main body 2, the ball screw 7 is arranged in the main body 2, one end of the ball screw 7 is fixedly connected with the output end of the driving element 4, and the other end is connected with the N end of the main body 2 through a rotary pair; the static support 1 is fixedly connected with the main body 2; the moving support 6 is fixedly connected with the screw nut 5 on the ball screw 7; one end of the bottom support 32 of the actuator 3 is connected with the static support 1, and the other end passes through the moving support 6 and is connected with the main body 2;

[0090] The static support 1 is fixed relative to the main body 2, the output end of the driving element 4 rotates to drive the ball screw 7 to rotate synchronously, the moving support 6 moves along the ball screw 7 with the screw nut 5 to realize the reciprocating linear motion, and the static support 1 and the moving support 6 move towards or away from each other.

[0091] The driving element can adopt a combination of a power supply and a rudder, or a combination of a power supply and a motor.

[0092] Referring to the accompanying drawings Figure 6 And 7 The actuator 3 further comprises a telescopic arm transverse sliding block 30, two groups of telescopic arm longitudinal guide rods 33, two groups of telescopic arm longitudinal sliding blocks 34, three groups of bottom support longitudinal sliding blocks 39 and a bottom support longitudinal guide rod 38;

[0093] One group of telescopic arm longitudinal guide rods 33 is fixedly installed on the static support 1 in the longitudinal direction; the other group of telescopic arm longitudinal guide rods 33 is fixedly installed on the moving support 6 in the longitudinal direction; and the bottom support longitudinal guide rod 38 is fixed on the main body 2 in the longitudinal direction;

[0094] The first group of bottom support longitudinal sliding blocks 39 is located at one end of the bottom support 32 and is in sliding connection with the telescopic arm longitudinal guide rod 33 on the static support 1;

[0095] The third group of bottom support longitudinal sliding blocks 39 is located at the other end of the bottom support 32 and is in sliding connection with the bottom support longitudinal guide rod 38 on the main body 2;

[0096] The telescopic arm transverse slider 30 is arranged on the bottom support 32 and can reciprocate transversely along the bottom support 32; the second group of bottom support longitudinal sliders 39 are arranged on the telescopic arm transverse slider 30 and are in sliding connection with the telescopic arm longitudinal guide rods 33 on the movable support;

[0097] The arrangement of the three groups of bottom support longitudinal sliders 39 can realize the longitudinal guidance of the bottom support 32.

[0098] The multi-link telescopic arm 37 is composed of two or more multi-link telescopic frames arranged in parallel, and the longitudinal two ends of each multi-link telescopic frame are respectively a P end and a Q end, the P end is connected with the bottom support 32, and the Q end is connected with the walking mechanism connecting block 36; the P end has two pin joints, one pin joint is connected with the end of the static support of the bottom support 32, and the other pin joint is connected with the telescopic arm transverse slider 30; the Q end has two pin joints, one pin joint is connected with one end of the walking mechanism connecting block 36; the walking mechanism connecting block 36 is provided with a transverse sliding groove, a sliding pin is arranged in the sliding groove, and the other pin joint of the Q end is connected with the end of the sliding pin; the transverse stretching or compression of the multi-link telescopic frame is realized.

[0099] The telescopic arm longitudinal sliders 34 are arranged on the telescopic arm longitudinal guide rods 33 on the static support 1 and are located above the first group of bottom support longitudinal sliders 39; the other telescopic arm longitudinal sliders 34 are arranged on the telescopic arm longitudinal guide rods 33 on the movable support 6 and are located above the second group of bottom support longitudinal sliders 39; the pin joints located in the longitudinal middle part of the multi-link telescopic frame and at the transverse two ends are respectively connected with the two groups of telescopic arm longitudinal sliders 34, so as to realize the guidance of the stretching and contraction of the multi-link telescopic arm 37.

[0100] In the specific embodiment, two multi-link telescopic frames are arranged in parallel, and a connecting rod 35 is arranged between the two multi-link telescopic frames to ensure the synchronous movement of the connecting rod and the stability of the multi-link telescopic arm 37.

[0101] Embodiment 2:

[0102] In this embodiment, the actuator guide is a guide disc 81, as shown in FIG. 8, the guide disc 81 is a disc structure, and the guide disc 81 is provided with a central hole 812; as shown in FIG. 9, the guide disc 81 is arranged on the bottom support 32 and is connected with the static support 1 of the bottom support 32. Figure 8 Figure 8 ​, the guide disc 81 is matched with the hole shaft of the ball screw 7 through the center hole 812 and is located between the static support 1 and the N end of the main body 2; the guide disc 81 can rotate with the ball screw 7; the guide groove is guide groove I 811, which is arranged on one surface of the guide disc 81 and is arc-shaped; the guide groove I 811 which is the same in number as the actuator 3 is centrally symmetrically distributed with the center hole 812 as the center, so that the two ends of the guide groove I 811 are A end and E end, and the distance from the A end of the guide groove I 811 to the center is less than the distance from the E end of the guide groove I 811 to the center; the guide boss 31 of each actuator 3 is arranged at the end of the end where the static support 1 of the bottom support 32 is located, and the guide boss 31 can slide along the corresponding guide groove I 811; when the guide boss 31 is located at the A end of the guide groove I 811, the bottom support 32 is located at the limit position I, corresponding to the minimum diameter of the diameter changing mechanism; when the guide boss 31 is located at the D end of the guide groove I 811, the bottom support 32 is located at the limit position II, corresponding to the maximum diameter of the diameter changing mechanism.

[0103] Further, referring to the accompanying drawings Figure 9 、 10 and 11, the actuator guide further comprises a harmonic reducer 813, which is arranged inside the N end of the main body 2; the harmonic reducer 813 comprises a steel wheel, a flexible wheel and a wave generator, the wave generator is coaxially arranged on the inner circumference of the flexible wheel, and the steel wheel is coaxially arranged on the outer circumference of the flexible wheel; the steel wheel is fixedly arranged inside the N end of the main body 2, the ball screw 7 is fixedly connected with the wave generator at one end of the N end of the main body 2, and the flexible wheel is fixedly connected with the guide disc 81; the wave generator is synchronously rotated by rotating the ball screw 7 through the driving element 4, the flexible wheel is decelerated and rotated by the wave generator, and the guide disc 81 is rotated after deceleration through the flexible wheel, so as to realize the speed control of the extension and contraction movement of the bottom support 32 and ensure the extension and contraction control precision and reliability.

[0104] Embodiment 3

[0105] This embodiment is based on embodiment 1, referring to the accompanying drawings Figure 12 , the guide boss 31 is arranged outside the length direction of the bottom support 32, the guide boss 31 is two groups, one group is arranged at the end where the static support 1 is located; the other group is fixedly arranged opposite to the telescopic arm transverse sliding block 30;

[0106] The actuator guide is a guide groove member 82, which is a plate structure arranged outside the length direction of the bottom support 32; the end of the static support of the guide groove member 82 is provided with a vertical guide groove 821 in the longitudinal direction, and the guide boss 31 at the end of the static support 1 is located in the vertical guide groove 821 and can move longitudinally along the vertical guide groove 821; the end of the dynamic support 6 of the guide groove member 82 is provided with an inclined guide groove 822, and the guide boss 31 fixed opposite to the telescopic arm transverse slider 30 is located in the inclined guide groove 822; when the dynamic support 6 moves towards the static support 1, the multi-link telescopic arm 37 is compressed transversely and the bottom support 32 is extended at the same time under the action of the inclined guide groove 822; when the multi-link telescopic arm 37 is stretched transversely, the bottom support 32 is retracted, and the diameter of the variable diameter mechanism is changed.

[0107] Embodiment 4:

[0108] This embodiment provides a pipeline robot based on a high compression ratio variable diameter mechanism in embodiment 1, as shown in the accompanying drawings Figure 13 and 14 , which comprises a main body 2, a variable diameter mechanism and a walking mechanism 9;

[0109] The walking mechanism 9 is fixedly connected with the walking mechanism connecting block 36 at the end of the actuator 3.

[0110] Each walking mechanism 9 comprises a mounting seat 93, a driving wheel 91 and a load wheel 92;

[0111] The mounting seat 93 is connected with the walking mechanism connecting block 36 at the end of the actuator 3, the driving wheel 91 and the load wheel 92 are installed side by side in the mounting seat 93 and arranged in the transverse direction; the middle part of the driving wheel 91 and the load wheel 92 is cylindrical, and the outer part of the driving wheel 91 and the load wheel 92 is provided with a track 94 in common, which is used to contact with the inner wall of the pipeline to realize the movement of the pipeline robot in the pipeline.

[0112] In a specific embodiment, the mounting seat 93 can be rotated by 90 degrees, so that the rotation axes of the driving wheel 91 and the load wheel 92 are arranged in the transverse direction, and any two walking mechanisms can rotate synchronously to realize the movement on flat ground.

[0113] In another specific embodiment, as shown in the accompanying drawings Figure 12 , the axial ends of each driving wheel 91 and load wheel 92 are provided with a circular truncated cone transition wheel; the small end of the transition wheel is rotatably connected with the mounting seat 93, and the large end of the transition wheel is fixedly connected with the cylindrical middle part; the number of walking mechanisms is (n+1) , and the taper angle of the transition wheel is , so that the transition wheels of two adjacent walking mechanisms can be located on a plane P to realize the movement on flat ground.

[0114] Embodiment 5

[0115] This embodiment is based on Embodiment 2 or Embodiment 4, and provides a linear variable-diameter method of a high-compression-ratio variable-diameter mechanism. The linear variable-diameter method is based on the design of the theoretical profile of the guide groove I 811 of the guide disc 81, so that the longitudinal length of the variable-diameter mechanism is in linear relationship with the movement length of the movable support 6 along the ball screw 7.

[0116] The design method of the theoretical profile is as follows:

[0117] Step S1: Determine the change trend of the lifting height of the bottom support 32 with the movement length of the screw nut 5 on the ball screw 7, so as to determine the trajectory trend of the theoretical profile. The specific method is as follows:

[0118] Referring to FIG. 2, let the movement length of the screw nut 5 on the ball screw 7 be L, the longitudinal length of the variable-diameter mechanism be L', and the lifting height of the bottom support 32 be H. Figure 15

[0119] is linear, so there is

[0120] Formula 1

[0121] wherein Lmax is the farthest distance that the screw nut 5 can move on the movable support 6; L' max is the longitudinal length of the variable-diameter mechanism when the screw nut 5 moves the farthest distance on the movable support 6; L'0 is the longitudinal length of the variable-diameter mechanism when the variable-diameter mechanism is not extended; Let the lifting height of the bottom support 32 be H, and the longitudinal height of the actuator 3 be H', there is

[0122]

[0123] Formula 2

[0124] According to Formula 2, Formula 3, Formula 4 and Formula 5 can be obtained:

[0125] Formula 3

[0126] Formula 4

[0127] wherein H'0 is the longitudinal height of the actuator 3 when the variable-diameter mechanism is not extended; H'max is the longitudinal height of the actuator 3 when the screw nut 5 moves the farthest distance on the movable support 6, H'max is the longitudinal height of the actuator 3 when the screw nut 5 moves the farthest distance on the movable support 6, Hmax is the lifting height of the bottom support 32 when the screw nut 5 moves the farthest distance on the movable support 6.​​​​​​

[0128] Equation 5

[0129] Substituting Equations 1, 3 and 4 into Equation 5, we have:

[0130] Equation 6

[0131] In Equation 6,

[0132] Equation 7

[0133] wherein, is the number of links of the multi-link telescopic arm, is the length of a single link in the multi-link telescopic arm, is the initial position of the moving bracket 6 is the distance from the static bracket.

[0134] According to the function image trial of Equation 6, the lifting height of the bottom support 32 is obtained the change trend of the movement length of the screw nut 5 on the ball screw 7 , so as to determine the trajectory trend of the theoretical profile, see Figure 16 ;

[0135] Step S2, based on the trajectory trend of the theoretical profile, the maximum value of is determined according to the constraint condition I of the theoretical profile ;

[0136] wherein the constraint condition I is: in order to ensure that each component does not interfere and the strength meets the demand, the limit minimum distance of any point on each theoretical profile from the center of the guide disc 81 is ; let the distance of the near stop point D of the theoretical profile from the center of the guide disc be , then we have:

[0137] Equation 8

[0138] wherein, is the distance of the end point E of the theoretical profile from the center of the guide disc; is the lowest height of the bottom support 32; performing function image trial on Equation 8, the maximum value of is obtained ;

[0139] Further, the method for obtaining in Equation 8 is: , , wherein, is the distance of the starting point A of the theoretical profile from the center of the guide disc.

[0140] Step S3, the result obtained in step S2 As Substituting into formula 6, we get the new... Then Transform the contour equation of the theoretical profile, and determine the maximum central angle formed by the endpoint E and the starting point A of the theoretical profile according to constraint condition II. Constraint condition II is: to ensure the strength meets the requirements, the minimum limit distance between any two adjacent theoretical profiles is... The specific method is as follows:

[0141] First, determine the profile equation of the theoretical profile:

[0142] Let the guide disk rotate at the angle of the drive element. The contour equation of the theoretical profile is: Then we have:

[0143] Formula 9

[0144] in, The distance from the starting point A of the theoretical profile to the center of the guide disk axis;

[0145] In Formula 9,

[0146] Formula 10

[0147] Then, determine the maximum central angle formed by the endpoint E and the starting point A of the theoretical profile. :

[0148] See appendix Figure 17 In this embodiment, four actuators are used, that is, four theoretical profiles are set on the guide plate. One of the theoretical profiles is called theoretical profile I, and the adjacent theoretical profile is called theoretical profile II. The starting point A, the near end point D, and the ending point E are all located on theoretical profile I. The starting point of theoretical profile II is the starting point B, and any point on theoretical profile I is the point C. The central angle formed by the starting point A, the starting point B and the axis O of the guide plate is 90°.

[0149] According to constraint II and the Law of Cosines, we have

[0150] Formula 10

[0151] By plotting the function graph according to Formula 10, we can obtain... maximum value ;

[0152] The theoretical profile designed through steps S1-S3 can achieve a linear relationship between the longitudinal length of the variable diameter mechanism and the movement length of the moving support 6 along the ball screw 7.

[0153] Embodiment 6:

[0154] This embodiment provides a specific embodiment based on Embodiment 5. In Step 1, it is known that the number of links of the multi-link telescopic arm , the length of a single link in the multi-link telescopic arm , the initial position of the movable bracket 6 , the distance from the static bracket , the maximum distance that the screw nut 5 can move on the movable bracket 6 ;

[0155] Substitute the above known conditions into Formulas 1-7, and perform function image trial according to Formula 6 to obtain the trajectory trend of the theoretical profile, as shown in FIG. 6, thereby determining the trajectory trend of the theoretical profile; Figure 16 In Step 2, it is known that the

[0156] , the distance from the end point E to the axis of the guide plate , the maximum value of ; ; ;

[0157] In Step S3, the , the distance from the start point A and the start point B to the axis of the guide plate ,

[0158] , the maximum value of ; .

[0159] According to Formulas 9 and , the trajectory of the theoretical profile can be determined, so that the longitudinal length of the variable-diameter mechanism and the movement length of the movable bracket 6 along the ball screw 7 are in linear relationship.

[0160] In summary, the above is only a preferred embodiment of the present application, and is not intended to limit the protection scope of the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high compression ratio variable diameter mechanism, as part of a pipeline robot, the pipeline robot also includes a main body located at the center and several walking mechanisms located around the main body, the variable diameter mechanism being installed between the main body and the walking mechanisms to realize the variable diameter of the pipeline robot; Its features are, The diameter-changing mechanism includes: a static support, an actuator, a moving support, and a drive assembly; Let the axis of the pipeline robot be the horizontal axis; let the radial axis of the pipeline robot be the vertical axis. The static support and the dynamic support are installed side by side and parallel to each other on the main body. The static support is fixed, while the dynamic support can move laterally under the action of the drive component, and can move towards or away from the static support. The actuator is located between the static support and the moving support; the actuator contains a multi-link telescopic arm, a bottom support, and a traveling mechanism connecting block. One end of the multi-link telescopic boom is slidably connected to the bottom support, and the other end is connected to the walking mechanism through the walking mechanism connecting block; the multi-link telescopic boom can perform longitudinal telescopic movement; When the drive assembly drives the moving support to move towards the stationary support, the multi-link telescopic arm is compressed laterally, the length of the multi-link telescopic arm is extended, and the bottom support extends longitudinally. When the driving element drives the moving support to move away from the static support, the multi-link telescopic arm stretches laterally, the length of the multi-link telescopic arm shortens, and the bottom support contracts longitudinally. The variable diameter mechanism also includes an actuator guide, with a guide boss on the bottom support and a guide groove on the actuator guide, the guide boss cooperating with the guide groove; When the drive assembly drives the moving bracket to move towards the stationary bracket, the bottom support extends longitudinally along the guide groove; When the driving element drives the moving bracket to move away from the stationary bracket, the bottom support retracts longitudinally along the guide groove. The drive assembly includes a drive element, a lead screw nut, and a ball screw; The main body has two ends, M and N, respectively. The drive element is fixedly installed at the M end inside the main body, and the ball screw is installed inside the main body. One end of the ball screw is fixedly connected to the output end of the drive element, and the other end is connected to the N end of the main body through a revolute joint. The stationary support is fixedly connected to the main body. The moving support is fixedly connected to the screw nut on the ball screw. One end of the bottom support of the actuator is connected to the stationary support, and the other end passes through the moving support and is connected to the main body. The stationary support is fixed relative to the main body. The output end of the drive element rotates, causing the ball screw to rotate synchronously. The moving support moves in a reciprocating linear motion along the ball screw with the screw nut, realizing the relative or distancing motion of the stationary support and the moving support. The actuator guide is a guide disc, which has a circular structure and a central hole. The guide disc engages with the ball screw shaft through the central hole and is located between the N end of the stationary support and the main body. The guide disc can rotate with the ball screw. The guide groove is guide groove I, which is set on one surface of the guide disc and is arc-shaped. The number of guide grooves I is the same as that of the actuator and is centrally symmetrically distributed with the central hole as the center. Let the two ends of guide groove I be ends A and E. The distance from end A of guide groove I to the center is less than the distance from end E to the center. The guide boss of each actuator is located at the end of the static support of the bottom support. The guide boss can slide along the corresponding guide groove I. When the guide boss is located at the A end of the guide groove I, the bottom support is located at the limit position I, which corresponds to the minimum diameter of the strain gauge mechanism. When the guide boss is located at the D end of the guide groove I, the bottom support is located at the limit position II, which corresponds to the maximum diameter of the strain gauge mechanism. The actuator guide may further include a harmonic reducer, which is disposed inside the N end of the main body; the harmonic reducer includes a steel wheel, a flexible wheel and a wave generator, the wave generator is coaxially disposed on the inner circumference of the flexible wheel and the steel wheel is coaxially disposed on the outer circumference of the flexible wheel; the steel wheel is fixedly disposed inside the N end of the main body, one end of the ball screw located at the N end of the main body is fixedly connected to the wave generator, and the flexible wheel is fixedly connected to the guide plate.

2. The high compression ratio variable diameter mechanism as described in claim 1, characterized in that, The actuator also includes a telescopic arm transverse slider, two sets of telescopic arm longitudinal guide rods, three sets of bottom support longitudinal sliders, and bottom support longitudinal guide rods. One set of telescopic boom longitudinal guide rods is fixedly installed on the static support along the longitudinal direction; another set of telescopic boom longitudinal guide rods is fixedly installed on the moving support along the longitudinal direction; the bottom support longitudinal guide rod is fixedly fixed on the main body along the longitudinal direction. The first set of bottom support longitudinal sliders is located at one end of the bottom support and is slidably connected to the telescopic arm longitudinal guide rod on the static support. The third set of bottom support longitudinal sliders is located at the other end of the bottom support and is slidably connected to the bottom support longitudinal guide rod on the main body; The telescopic arm's lateral slider is mounted on the bottom support, enabling it to reciprocate laterally along the bottom support. The second set of bottom support longitudinal sliders is set on the telescopic arm transverse slider and is slidably connected to the telescopic arm longitudinal guide rod on the moving bracket; The multi-link telescopic boom is composed of one or more multi-link telescopic frames arranged in parallel, with the longitudinal ends of each multi-link telescopic frame being end P and end Q, respectively, and end P being connected to the bottom support; The Q end is connected to the traveling mechanism connecting block; the P end has two pin joints, one pin joint is pinned to the end of the static support of the bottom support, and the other pin joint is pinned to the telescopic arm lateral slider; the Q end has two pin joints, one pin joint is pinned to one end of the traveling mechanism connecting block; the traveling mechanism connecting block is provided with a lateral sliding groove, and a sliding pin is provided in the sliding groove, and the other joint of the Q end is pinned to the end of the sliding pin.

3. The high compression ratio variable diameter mechanism as described in claim 2, characterized in that, The actuator also includes two sets of telescopic arm longitudinal sliders. One set of telescopic arm longitudinal sliders is slidably mounted on the telescopic arm longitudinal guide rod on the static support and is located above the first set of bottom support longitudinal sliders. The other set of telescopic arm longitudinal sliders is slidably mounted on the telescopic arm longitudinal guide rod on the moving support and is located above the second set of bottom support longitudinal sliders. The pin joints located in the longitudinal middle of the multi-link telescopic frame and at both transverse ends are respectively pin-connected to the two sets of telescopic arm longitudinal sliders.

4. A high compression ratio variable diameter mechanism as described in any one of claims 2-3, characterized in that, The guide boss is located on the outer side of the bottom support along its length. There are two sets of guide bosses: one set is located at the end where the static support is located; the other set is fixed relative to the transverse slider of the telescopic arm. The actuator guide component is a guide groove component, which is a plate-shaped structure located on the outer side of the bottom support along its length. A vertical guide groove is provided at the static support end of the guide groove component, and a guide boss at the static support end is located within the vertical guide groove, allowing for longitudinal movement along the vertical guide groove. An inclined guide groove is provided at the moving support end of the guide groove component, and a guide boss, fixed relative to the transverse slider of the telescopic arm, is located within the inclined guide groove. When the moving support moves towards the static support, under the action of the inclined guide groove, the multi-link telescopic arm is laterally compressed while the bottom support extends; when the multi-link telescopic arm is laterally extended, the bottom support retracts.

5. A pipeline robot, comprising a diameter-changing mechanism, a main body, and a walking mechanism; characterized in that, The variable diameter mechanism adopts the high compression ratio variable diameter mechanism of any one of claims 1-4; The variable diameter mechanism has two or more actuators, which are arranged radially around the outer circumference of the main body. The end of the traveling mechanism is fixedly connected to the end of the actuator; Each walking mechanism includes a mounting base, drive wheels, and load-bearing wheels; The mounting base is connected to the end of the actuator. The drive wheel and the load wheel are installed side by side in the mounting base and arranged along the length of the main body. The middle part of the drive wheel and the load wheel are both cylindrical. The drive wheel and the load wheel are jointly provided with a track for contacting the inner wall of the pipe.

6. A linear diameter-changing method for a high compression ratio variable diameter mechanism, based on the high compression ratio variable diameter mechanism described in claim 1, characterized in that, The design of the theoretical profile of the guide groove I based on the guide plate makes the longitudinal length of the variable diameter mechanism linearly related to the movement length of the moving support along the ball screw; The design method for the theoretical profile is as follows: Step S1: Determine the trend of the rise of the bottom support as the lead screw nut moves along the ball screw, thereby determining the trajectory trend of the theoretical profile; Step S2: Based on the trajectory trend of the theoretical profile, determine the maximum rise height of the bottom support according to constraint condition I of the theoretical profile. ; Constraint condition I is: to ensure that the components do not interfere with each other and that the strength meets the requirements, the minimum distance from any point on each theoretical profile to the center of the guide disk is... ; Step S3, based on the maximum height of the bottom support obtained in step S2. The function that yields the height of the bottom support. Then Transform the contour equation of the theoretical profile, and determine the maximum central angle formed by the endpoint E and the starting point A of the theoretical profile according to constraint condition II. ; Among them, constraint condition II is: to ensure that the strength meets the requirements, the minimum limit distance between any two adjacent theoretical contour lines is... ; The theoretical profile designed through steps S1-S3 can achieve a linear relationship between the longitudinal length of the variable diameter mechanism and the movement length of the moving support along the ball screw.

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