Four-degree-of-freedom travelling crane trolley with adjustable movement axis

Abstract

The invention discloses a four-degree-of-freedom traveling crane trolley with an adjustable movement axis, and relates to the technical field of traveling crane trolleys, the four-degree-of-freedom traveling crane trolley comprises a traveling crane trolley body, a pitching driving system, a yawing driving system and a linear guide rail assembly; the travelling crane trolley body is erected on an external steel rail through the force bearing wheels and the driving wheels, so that first-degree-of-freedom movement along the steel rail is realized; the pitching driving system is connected between the travelling crane trolley body and the yaw driving system to realize a second degree of freedom; the yaw driving system is connected between the pitching driving system and the linear guide rail assembly to realize a third degree of freedom; the linear guide rail assembly drives an external load to do linear motion, and the fourth degree of freedom is achieved. According to the invention, the following problems are solved: the cooperation of large-range movement and local high precision is realized; the load mounting space is optimized, so that the load can sink into the mechanism, the overall gravity center and height are reduced, and the system stability is improved; load distribution is improved, mechanism rigidity is improved, and rigidity loss caused by structure stacking is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of row and suspension trolley, in particular to a four-degree-of-freedom row and suspension trolley with adjustable motion axis. BACKGROUND

[0002] The existing row and suspension trolley adopts a cross-stacked linear guide rail module to realize motion adjustment, wherein a load is connected to the Y-axis linear guide rail through a slider load platform, and the load is driven to move linearly along the Y-axis by means of a Y-axis screw; the Y-axis linear guide rail is connected to the X-axis guide rail slider through a Y-axis base, and the X-axis guide rail is installed on the X-axis base, and the Y-axis as a whole is driven to move linearly along the X-axis by means of an X-axis screw, so as to adjust the motion axis of the Y-axis guide rail. The existing technology has the following significant defects: precision and range contradiction: if the row and suspension trolley needs to realize large-range movement, the motion precision often needs to be sacrificed, and the use requirements of "large-range movement" and "local high precision" cannot be met; low space utilization: the load can only be connected to the upper part of the guide rail through the slider load platform, and cannot be sunk into the internal mechanism, resulting in high overall height and high center of gravity of the device and load, and poor system running stability; uneven stress and rigidity: the stress of the cross-stacked structure is concentrated at the connection position of the X-axis and the Y-axis, the load is unevenly distributed, the rigidity of the mechanism is poor, and the motion deviation is easily caused by vibration or heavy load. SUMMARY

[0003] The technical problem to be solved by the present application is to provide a four-degree-of-freedom row and suspension trolley with adjustable motion axis, which solves the following problems: realizes the cooperation of "large-range movement" and "local high precision", meets the precision requirements of docking and posture adjustment scenes, optimizes the load installation space, makes the load sink into the internal mechanism, reduces the overall center of gravity and height, and improves the system stability, improves the load distribution, improves the rigidity of the mechanism, and avoids the loss of rigidity caused by the stacking of the structure.

[0004] To solve the above problems, the technical scheme provided by the present application is as follows:

[0005] A four-degree-of-freedom row and suspension trolley with adjustable motion axis, comprising a row and suspension trolley body, a pitch driving system, a yaw driving system and a linear guide rail assembly; the row and suspension trolley body is arranged on the external steel rail through a load-bearing wheel and a driving wheel, realizing the first degree of freedom movement along the steel rail; the pitch driving system is connected between the row and suspension trolley body and the yaw driving system, used to drive the yaw driving system and the linear guide rail assembly to make pitch motion around the preset axis, realizing the second degree of freedom; the yaw driving system is connected between the pitch driving system and the linear guide rail assembly, used to drive the linear guide rail assembly to make yaw motion around the center of the circular arc, realizing the third degree of freedom; the linear guide rail assembly drives the external load to make linear motion, realizing the fourth degree of freedom.

[0006] The structure of the four-degree-of-freedom trolley realizes decoupling and collaborative control of multi-directional movement through layered collaborative design. The trolley body relies on the driving wheel and the load wheel to realize large-range coarse adjustment (first degree of freedom) on the external steel rail, providing basic movement ability for the system; the pitch driving system drives the subsequent components to pitch around the preset axis (second degree of freedom) by connecting the trolley body and the yaw driving system, adapting to the longitudinal adjustment demand of the load posture; the yaw driving system further connects the pitch system and the linear guide assembly, realizing yaw movement in the horizontal plane (third degree of freedom), and expanding the horizontal orientation adjustment range of the load; the linear guide assembly finally drives the load to perform precise linear movement (fourth degree of freedom), realizing local high-precision positioning. This structure solves the contradiction between precision and range by separating large-range movement and precise adjustment functions; by allowing the load to sink into the internal mechanism, the space utilization is optimized and the center of gravity is reduced; by using a non-stacked force transmission path, the load distribution and system rigidity are improved.

[0007] As an option, the pitch driving system includes a lifter, a single-degree-of-freedom hinge, a lifter push rod hinge, and a hinge; the single-degree-of-freedom hinge is rotationally connected to the frame of the trolley body, and the lifter push rod hinge is hingedly connected to the circular arc guide rail mounting rack; the lifter is connected on both sides with a lifting seat having a gear and rack structure through a lifting bidirectional gear shaft, and the lifting seat is hingedly connected to the circular arc guide rail mounting rack; the extension and retraction of the telescopic push rod of the lifting seat drive the circular arc guide rail mounting rack to rotate around the single-degree-of-freedom hinge.

[0008] The core function of the pitch driving system is to realize the pitch posture adjustment (second degree of freedom) of the yaw driving system and the linear guide assembly. The lifter (usually an electric push rod) serves as the core power source, providing linear thrust or pull; the single-degree-of-freedom hinge acts as a fixed rotational fulcrum for system movement, restricting the pitch movement in a single plane and ensuring movement accuracy; the lifter push rod hinge and the middle hinge together constitute a stable force transmission and movement conversion mechanism, which converts the linear extension and retraction movement of the lifter push rod into the rotary movement of the circular arc guide rail mounting rack around the single-degree-of-freedom hinge axis. The system functions to convert compact linear driving into a large range of pitch angle changes, and its hinged layout optimizes force flow transmission, avoids structural jamming, and withstands the moment load from the upper components, ensuring the stability and reliability of the pitch movement.

[0009] As an option, the yaw driving system includes a circular arc guide rail, a circular arc guide rail mounting rack, a circular arc rack, and a yaw driving gear; the circular arc guide rail is fixed to the upper surface of the circular arc guide rail mounting rack, and the circular arc rack is fixed along the arc profile of the circular arc guide rail; the yaw driving gear is engaged with the circular arc rack, and the yaw driving gear is driven by a yaw driving motor; through the meshing transmission of the yaw driving gear and the circular arc rack, the linear guide assembly is driven to rotate around the center of the circular arc guide rail.

[0010] The core function of the yaw drive system is to realize the rotation adjustment (third freedom) of the linear guide assembly and its load in the horizontal plane. The circular guide rail and the circular guide rail mounting frame jointly constitute the rigid support foundation and the movement track of the system, providing precise arc path constraint and bearing for the yaw movement; the circular arc rack serves as a fixed transmission element, converting the circular motion into a linear tooth profile; the yaw drive gear serves as a driving element, meshing with the circular arc rack and converting the rotation power of the motor into traction force along the rack. The system accurately and smoothly converts the rotation movement of the driving motor into the rotary movement of the linear guide assembly around the fixed center, thereby realizing the large-angle and high-precision stepless adjustment of the horizontal orientation of the load. The overall circular design intersects the rotation axis and the pitch axis, optimizes the force flow transmission, and avoids the torque load and precision loss caused by the stacked structure.

[0011] As an option, the linear guide assembly includes a linear guide mounting frame, a linear guide rail, and a load connecting slider; the linear guide mounting frame is a hollow frame structure, and its lower surface is fixedly connected with the slider of the circular guide rail; the linear guide rail is fixed along the length direction of the linear guide mounting frame, and the load connecting slider is in sliding fit with the linear guide rail and is fixedly connected with the external load.

[0012] The core function of the linear guide assembly is to realize the precise linear movement (fourth freedom) of the load and serve as an integrated platform for bearing and connecting other subsystems. The linear guide mounting frame serves as the core bearing and structural basis, and its hollow frame design greatly reduces the overall weight and creates a space for the external load to extend upward and be fixed, thereby greatly optimizing the structural layout and lowering the overall gravity center. The linear guide rail is fixed on the frame to provide high-precision and high-rigidity guidance and support for the load movement. The load connecting slider, as the execution component directly fixed with the load, transmits the power of the linear drive element (screw or linear motor not shown in the figure) to the load and accurately slides along the guide rail. The function of the assembly is to finally convert the linear direction after the yaw movement into the precise linear displacement of the load. The sinking design solves the load installation space problem and realizes the final execution of "large-range movement" and "local high-precision" at the end.

[0013] As an option, one side of the linear guide rail is provided with a driving rack, and the load connecting slider is provided with a driving gear meshing with the driving rack. The driving gear is driven by an external motor to move the load connecting slider and the load along the linear guide rail.

[0014] The driving rack is fixed on one side of the linear guide rail, serving as a long-stroke and high-precision linear power source; the driving gear is integrated with the load-connected slider, serving as the driving part to convert the rotary motion of the motor into linear traction force; the external motor provides the original power for the system. The core function of this mechanism is to overcome the elastic deformation, slipping or creep problems of traditional belt or screw transmission under long-stroke and heavy load through gear and rack meshing transmission, ensuring high positioning accuracy and repeatability in a wide range of movement. Its rigid contact characteristics significantly improve the response speed, carrying capacity and anti-interference of the system, directly meeting the driving demand of "local high precision".

[0015] As an option, the linear guide rail mounting frame is made of aluminum alloy by integral molding.

[0016] The aluminum alloy material provides excellent specific strength (strength to weight ratio), and the integral molding technology avoids the additional weight, stress concentration and connection loosening risk caused by traditional welding or bolt connection. The internal hollow design is easily realized, further reducing the weight and creating a load embedding space. Finally, this design significantly reduces the inertia of the moving parts, improves the dynamic response speed, motion accuracy and energy efficiency of the system, while ensuring the stability of the load.

[0017] As an option, the telescopic stroke range of the telescopic push rod is 0-100mm, and the pitch angle adjustment range of the yaw driving system is ±5°.

[0018] The telescopic stroke of 0-100mm provides sufficient actuation range to generate sufficient lever arm, and the pitch angle range of ±5° is precisely calculated to meet the necessary attitude adjustment requirements of the load in the vertical plane (such as compensating for height difference or leveling during docking), while avoiding excessive movement that may cause mechanism interference or stability decline. The electric push rod as an actuator has the characteristics of high-precision position control, self-locking and good load capacity, directly ensuring the accuracy and reliability of the second degree of freedom movement.

[0019] As an option, the load-bearing wheels and driving wheels are symmetrically installed on both sides of the vehicle frame, and the driving wheels are connected to the external servo motor through a speed reducer.

[0020] The force bearing wheel is symmetrically installed on both sides of the frame, and mainly functions to bear and disperse the overall weight of the trolley body and the load carried by the trolley body to the external rail, and to provide stable support to prevent overturning. The driving wheel is also symmetrically installed, and is directly connected with the external servo motor through a speed reducer, and functions to convert the accurate rotation output of the servo motor into friction between the driving wheel and the rail, so as to provide accurate traction for the trolley. The symmetrically installed layout ensures uniform distribution of the load and centralization of the driving force action point, avoids sticking or deviation during operation, and provides a stable and flat moving platform for the three degrees of freedom of the precise movement.

[0021] Optionally, the curvature radius of the circular arc guide rail is 800-2000 mm, the modulus of the yaw driving gear and the circular arc rack is 1-3, and the yaw angle adjustment range of the yaw driving system is ±5°.

[0022] The curvature radius range of 800-2000 mm is an optimized compromise design, a smaller radius makes the structure more compact, and a larger radius can provide a smoother movement trajectory and a larger internal space; the gear and rack pair with a modulus of 1-3 balances the transmission accuracy and torque load, a small modulus is beneficial to high precision and low noise transmission, and a larger modulus can transmit greater torque, which is suitable for heavy load working conditions; the yaw angle range of ±5° ensures that the load has sufficient orientation adjustment capability in the horizontal plane to meet the needs of most docking and posture adjustment scenes, while avoiding complex problems such as cable winding caused by infinite rotation.

[0023] Optionally, the three degrees of freedom guide rail module is integrated by the pitch driving system, the yaw driving system and the linear guide rail assembly, and the three degrees of freedom guide rail module is detachably connected with the trolley body of the travelling crane.

[0024] Highly integrating the three precise movement degrees of freedom (the second, third and fourth degrees of freedom) of pitch, yaw and straight line in one module makes it an independent functional unit, which greatly simplifies the structure design, assembly process and precision debugging work of the whole machine. The detachable connection between the trolley body of the travelling crane (the first degree of freedom) and the three degrees of freedom module gives the system high flexibility, maintainability and expandability. The design allows users to quickly replace or upgrade different three degrees of freedom modules according to different task requirements (such as load type, working range and precision requirement), without changing the basic crane structure; at the same time, it greatly facilitates transportation, on-site installation and later maintenance and repair, and reduces the use cost throughout the life cycle.

[0025] Compared with the prior art, the technical scheme provided by the application has the following beneficial effects:

[0026] Four-degree-of-freedom cooperative adjustment: through the cooperation of the trolley body (X-direction movement), the pitch driving system (pitch around the Y-axis), the yaw driving system (yaw around the Z-axis), and the linear guide rail assembly (linear motion along the guide rail axis), four-degree-of-freedom motion is realized to meet the complex motion requirements of the docking and attitude adjustment scene;

[0027] Precision and range balance: the three-degree-of-freedom guide rail module (pitch, yaw, and linear motion) is integrated into the trolley body, the trolley realizes large-range movement, and the three-degree-of-freedom module realizes local high-precision adjustment, solving the contradiction between large range and high precision;

[0028] Space utilization and stability improvement: the linear guide rail installation frame adopts an internal hollow design, the load can sink into the internal frame, reducing the overall gravity center height by more than 30%, reducing vibration interference, and improving system operation stability;

[0029] Rigidity and stress optimization: the yaw driving system uniformly distributes the load through the arc guide rail and the arc-shaped structure of the arc guide rail installation frame 5, and the pitch driving system disperses the stress through the elevator and the double hinge structure, avoiding the rigidity loss of the traditional stacked structure, and improving the overall rigidity of the mechanism;

[0030] High attitude adjustment flexibility: the pitch driving system and the yaw driving system are independently controlled, and can respectively adjust the pitch angle and the yaw angle of the linear guide rail 8, adapting to the axis adjustment requirements of different docking scenes. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 A motion schematic diagram of a four-degree-of-freedom trolley with adjustable motion axis is proposed for the embodiments of the present application;

[0032] Figure 2 A structure schematic diagram of a four-degree-of-freedom trolley with adjustable motion axis is proposed for the embodiments of the present application;

[0033] Figure 3 A local structure schematic diagram of a four-degree-of-freedom trolley with adjustable motion axis is proposed for the embodiments of the present application;

[0034] Figure 4 A top view of a four-degree-of-freedom trolley with adjustable motion axis is proposed for the embodiments of the present application;

[0035] Figure 5 A side view of a four-degree-of-freedom trolley with adjustable motion axis is proposed for the embodiments of the present application, removing the trolley body;

[0036] Figure 6 An elevator end structure schematic diagram of a four-degree-of-freedom trolley with adjustable motion axis is proposed for the embodiments of the present application;

[0037] Figure 7 A partial top view of the lifting end of a four-degree-of-freedom trolley with an adjustable motion axis proposed in an embodiment of the present invention;

[0038] Figure 8 A bottom view of the transmission end of a four-degree-of-freedom trolley with an adjustable motion axis, as proposed in an embodiment of the present invention;

[0039] 1. Rail; 2. Single-degree-of-freedom hinge; 3. Lift push rod hinge; 4. Hinge; 5. Arc guide rail mounting frame; 6. Arc guide rail; 7. Linear guide rail mounting frame; 8. Linear guide rail; 9. Load; 10. Load-bearing wheel; 11. Drive wheel; 12. Lift; 13. Arc rack; 14. Yaw drive gear; 15. Lift push rod; 16. Lifting seat; 17. Lifting bidirectional gear shaft; 18. Overhead crane trolley body; 19. Bull's eye bearing mounting column; 20. Bull's eye bearing mounting body; 21. Yaw drive motor; 22. Yaw beam. DETAILED DESCRIPTION

[0040] In order to further understand the content of the present invention, the present invention is described in detail with reference to the accompanying drawings and embodiments.

[0041] Example 1

[0042] Combined with attachment Figures 1-2 A four-degree-of-freedom traveling crane trolley with an adjustable motion axis includes a traveling crane trolley body 18, a pitch drive system, a yaw drive system and a linear guide rail 8 assembly; the traveling crane trolley body 18 is mounted on an external steel rail 1 through a load-bearing wheel 10 and a driving wheel 11 to achieve a first degree of freedom movement along the steel rail 1; the pitch drive system is connected between the traveling crane trolley body 18 and the yaw drive system, and is used to drive the yaw drive system and the linear guide rail 8 assembly to perform pitch motion around a preset axis to achieve a second degree of freedom; the yaw drive system is connected between the pitch drive system and the linear guide rail 8 assembly, and is used to drive the linear guide rail 8 assembly to perform yaw motion around the center of an arc to achieve a third degree of freedom; the linear guide rail 8 assembly drives the external load 9 to perform linear motion to achieve a fourth degree of freedom.

[0043] When the system is running, the trolley body 18 first moves along the rail 1 through the drive wheel 11 to realize large-scale translation of the load 9 (first degree of freedom); the pitch driving system (such as a hinged mechanism and a pitch motor) drives the yaw driving system and the linear guide rail 8 assembly to rotate around the transverse axis to change the pitch angle of the load 9 (second degree of freedom); the yaw driving system (such as a rotary support and a yaw motor) drives the linear guide rail 8 assembly to rotate around the vertical axis to adjust the horizontal direction of the load 9 (third degree of freedom); and the linear guide rail 8 assembly (such as a precision screw or a linear motor) finally drives the load 9 to move accurately and linearly along the guide rail direction (fourth degree of freedom). The degrees of freedom work together through independent driving units, first quickly position through large-scale movement, then adjust the posture through pitch / yaw, and finally realize silk-level precise docking through the linear guide rail 8, with an accuracy of 0.02 mm, so as to balance the movement range and precision.

[0044] In combination with the accompanying drawings Figures 5-8 The pitch driving system comprises an elevator 12, a single-degree-of-freedom hinge 2, an elevator push rod hinge 3, and a hinge 4; the single-degree-of-freedom hinge 2 is rotationally connected with the frame of the trolley body 18, the elevator push rod hinge 3 is hingedly connected with the circular arc guide rail mounting frame 5; the seat body of the lifting seat 16 connected with the elevator 12 through the lifting bidirectional gear shaft 17 is hingedly connected with the circular arc guide rail mounting frame 5 through the hinge 4; the extension and retraction of the telescopic push rod drives the circular arc guide rail mounting frame 5 to rotate around the single-degree-of-freedom hinge 2. The end of the circular arc guide rail mounting frame 5 is further provided with a bull's eye bearing mounting column 19, the top of the bull's eye bearing mounting column 19 is provided with a bull's eye bearing mounting body 20, the bull's eye bearing mounting column 19 is mounted on the circular arc guide rail mounting frame 5, the bull's eye bearing mounting body 20 is located above the support frame and below the circular arc guide rail 6, the other end of the support frame is connected with the linear guide rail mounting frame, and the lower part of the support frame is provided with a friction pad abutting against the bull's eye bearing mounting body 20 to balance the moment generated by the lifting force of the elevator 12 on the circular arc guide rail 6.

[0045] The pitch driving system operates based on the four-bar linkage principle. When the push rod of the elevator 12 starts to extend or retract, the linear pushing or pulling force generated thereby is transmitted to the circular arc guide rail mounting frame 5 through the elevator push rod hinge 3. Since the seat body of the lifting seat 16 connected with the elevator 12 through the lifting bidirectional gear shaft 17 is connected with the mounting frame through the hinge 4, this point becomes a movable force action point. At the same time, the rear part of the entire mounting frame is fixedly connected with the frame of the trolley body 18 through the single-degree-of-freedom hinge 2, and the hinge 4 point constitutes the center of rotation (the rotation axis). The linear motion (extension or retraction) of the push rod forces the circular arc guide rail mounting frame 5 to rotate upward or downward around the axis of the single-degree-of-freedom hinge 2 as the center, thereby driving the entire yaw driving system and the linear guide rail 8 assembly fixed thereon to complete the pitch action. During the entire process, multiple hinges 4 work together to smoothly convert the driving force into a rotational moment and allow the mechanism to adapt to slight position changes during movement, ensuring smooth movement and no over-constraint.

[0046] In combination with the drawings Figure 8 The yaw drive system comprises a circular arc guide rail 6, a circular arc guide rail mounting frame 5, a circular arc rack 13 and a yaw drive gear 14. The circular arc guide rail 6 is fixed to the upper surface of the circular arc guide rail mounting frame 5, and the circular arc rack 13 is fixed along the arc profile of the circular arc guide rail 6. The yaw drive gear 14 is engaged with the circular arc rack 13, and the yaw drive gear 14 is driven by a yaw drive motor 21. Through the meshing transmission of the yaw drive gear 14 and the circular arc rack 13, the linear guide rail 8 assembly is driven to rotate around the center of the circular arc guide rail 6.

[0047] The yaw drive system operates based on the gear and rack meshing transmission principle. After the yaw drive motor 21 is started, the output torque drives the yaw drive gear 14 to rotate. Due to the mutual engagement of the gear and the circular arc rack 13, the rotational movement of the gear generates a reaction force to push the entire gear mechanism and the yaw beam 22 fixed thereto to rotate around the center of the circular arc guide rail 6 along the trajectory of the circular arc guide rail 6 (i.e. the effect of "the gear crawling on the fixed rack"). The circular arc guide rail 6 restricts the movement path of the yaw beam 22 through the rollers thereon, ensuring that it rotates smoothly along the predetermined arc-shaped trajectory, thereby achieving precise yaw angle control. The yaw beam 22 is fixed between the linear guide rail mounting frames 7, the circular arc guide rail 6 cooperates with the rollers, and the circular arc rack 13 and the circular arc guide rail 6 are integrated. The rollers are installed below the sliding seat, and the sliding seat is fixed to the motor housing of the yaw drive motor 21.

[0048] In combination with the drawings Figures 1-2 The linear guide rail 8 assembly comprises a linear guide rail 8 mounting frame 7, a linear guide rail 8 and a load 9 connecting slide block. The linear guide rail 8 mounting frame 7 is a hollow frame structure, and its lower surface is fixedly connected with the slide block of the circular arc guide rail 6. The linear guide rail 8 is fixed along the length direction of the linear guide rail 8 mounting frame 7, the load 9 connecting slide block is in sliding cooperation with the linear guide rail 8, and the load 9 connecting slide block is fixedly connected with the external load 9.

[0049] When the linear drive source (such as a lead screw motor or a linear motor) integrated in the assembly is working, it will drive the load 9 connecting slide block to make precise linear motion along the fixed linear guide rail 8. Since the load 9 is directly fixed on the slide block, the load 9 also realizes precise linear movement (fourth degree of freedom). The entire linear guide rail 8 mounting frame 7 is fixed through its lower surface with the slide block of the circular arc guide rail 6, which means that when the yaw drive system is working (third degree of freedom), it will drive the entire frame and the linear guide rail 8, slide block and load 9 thereon to rotate around the center, thereby changing the final direction of linear motion. The hollow frame structure enables the load 9 body to be embedded therein, achieving the reduction of the overall height of the device and the sinking of the center of gravity, and improving the running stability.

[0050] One side of the linear guide rail 8 is provided with a driving rack, and the load 9 connecting slider is provided with a driving gear engaged with the driving rack. The driving gear is driven by an external motor, and is used to drive the load 9 connecting slider and the load 9 to move along the linear guide rail 8.

[0051] When the external motor is started, the output shaft of the motor drives the driving gear to rotate. Since the driving gear is engaged with the driving rack fixedly installed beside the linear guide rail 8, the rotating gear cannot move along the rack by itself, but will generate a huge reaction force due to the engagement. The reaction force pushes the entire load 9 connecting slider (and the driving motor and external load 9 fixedly connected therewith) to move accurately along the guide direction of the linear guide rail 8. The rotation speed of the motor controls the rotation speed of the gear, and further controls the moving speed of the slider; the number of rotations of the motor accurately corresponds to the number of teeth rolled on the rack by the gear, so that the position of the slider is accurately controlled in a closed loop.

[0052] The linear guide rail 8 mounting frame 7 is integrally formed by aluminum alloy.

[0053] During operation, when the yaw driving system drives the entire frame to rotate around the center (third degree of freedom), the low weight means smaller rotational inertia, so that the yaw motor has smaller load, starts and stops more quickly, and is controlled more accurately. When the load 9 connecting slider moves at high speed or high precision on the frame (fourth degree of freedom), the high rigidity and the stability of the integrally formed ensure that the frame will not be distorted or vibrated due to acceleration, deceleration or eccentric loading of the load 9, so as to directly transfer the precision of the driving unit to the end load 9, and avoid positioning errors caused by deformation of the basic structure.

[0054] The telescopic stroke range of the telescopic push rod is 0-100mm, and the adjustment range of the pitch angle of the yaw driving system is ±5°.

[0055] The telescopic end of the electric push rod is connected with the circular arc guide rail mounting frame 5 through the elevator push rod hinge 3, the fixed end of the push rod is connected with the mounting frame through the middle hinge 4, and the mounting frame itself is connected with the vehicle frame to form a rotating support point through the single degree of freedom hinge 2. When the telescopic push rod of the electric push rod is extended or shortened within the range of 0 to 100mm, it will push or pull the circular arc guide rail mounting frame 5 to rotate around the axis of the single degree of freedom hinge 2. The linear displacement (X) of the push rod and the rotation angle (θ) of the mounting frame are accurately converted through a set of trigonometric functions (which depends on the relative positions of several hinge points). Through mechanical design, the maximum stroke of the push rod is limited to 100mm, which just restricts the limit position of the pitch angle within ±5°. The system can accurately control the pitch angle by controlling the telescopic amount of the push rod.

[0056] The load bearing wheels 10 and the driving wheels 11 are symmetrically installed on both sides of the vehicle frame, and the driving wheels 11 are connected with the external servo motor through a speed reducer.

[0057] When the overhead crane trolley needs to be moved, the control system sends a command to the external servo motor, and the motor output shaft generates precise speed and torque. The output is transmitted to the drive wheel 11 through the reducer. The drive wheel 11 drives the entire trolley along the track through the static friction with the external rail 1. The torque required for direct drive of the motor is too large, resulting in the doubling of the power of the motor selection. The reducer can reduce the output speed while greatly increasing the output torque, allowing a small motor to drive a large load. The symmetrically arranged load-bearing wheels 10 then rotate accordingly, jointly bearing the load 9 and maintaining the balance of the vehicle body. The closed-loop control characteristics of the servo motor enable it to accurately control the distance, speed and acceleration of movement, thereby achieving precise positioning in a large range of movement.

[0058] The curvature radius of the circular arc guide rail 6 is 800-2000 mm, the module of the yaw drive gear 14 and the circular arc rack 13 is 1-3, and the yaw angle adjustment range of the yaw drive system is ±5°. The curvature radius of the circular arc guide rail 6 can be 800, 1500 or 2000 mm.

[0059] The radius of curvature (R) directly determines the physical dimensions of the arc rack 13 and the relationship between the yaw angle (θ) and the gear rolling arc length (S) (S = R * θ). Within a fixed angle range of ±5°, a larger radius R means the gear needs to roll over a longer arc length S, which typically requires a longer rack and larger installation space, but results in smoother motion and higher resolution. A smaller radius R makes the system more compact. The gear module (m), which is related to the pitch circle diameter (d) and the number of teeth (Z) (d = m * Z), determines gear size, tooth strength, and meshing controllability. A larger module increases the load capacity of a single tooth, but may affect motion smoothness and accuracy. During system operation, a servo motor drives the yaw drive gear 14 to rotate, meshing and rolling on the fixed rack. The number of revolutions is converted into a precise linear rolling distance using the module and pitch circle diameter, and then converted into a yaw angle using the radius of curvature (θ = S / R), achieving precise and rigid closed-loop control over the entire ±5° yaw angle range.

[0060] The three-degree-of-freedom guide rail module is integrated with the pitch drive system, the yaw drive system and the linear guide rail 8 components, and the three-degree-of-freedom guide rail module is detachably connected to the crane trolley body 18.

[0061] In the running time, the three driving systems of pitch, yaw and straight line can move independently or compoundly under the coordination of the control system, and guide the end load 9 to reach any target pose in the working space. The motion chain is: the basic large range movement of the crane trolley body 18 (the first degree of freedom) → the pitch driving system drives the yaw system and the straight line assembly on it to pitch with the single degree of freedom hinge 2 as the axis (the second degree of freedom) → the yaw driving system drives the straight line guide rail 8 assembly to yaw around the center of the circular arc in the pitch pose (the third degree of freedom) → the straight line guide rail 8 assembly finally realizes the precise straight line extension and retraction movement (the fourth degree of freedom).

[0062] The above description of the present application and its embodiments is illustrative and not restrictive, and the embodiments shown in the drawings are only one of the embodiments of the present application, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by it, without departing from the purpose of the present application, similar structure and embodiments can be designed without creativity, which should belong to the protection scope of the present application.

Claims

1. A four-degree-of-freedom crane trolley with an adjustable motion axis, characterized in that: The invention comprises a traveling crane trolley body, a pitch drive system, a yaw drive system and a linear guide assembly; the traveling crane trolley body is mounted on an external steel rail (1) through a load-bearing wheel (10) and a drive wheel (11), so as to realize movement with a first degree of freedom along the steel rail (1); the pitch drive system is connected between the traveling crane trolley body and the yaw drive system, and is used to drive the yaw drive system and the linear guide assembly to perform pitch motion around a preset axis, so as to realize a second degree of freedom; the yaw drive system is connected between the pitch drive system and the linear guide assembly, and is used to drive the linear guide assembly to perform yaw motion around the center of an arc, so as to realize a third degree of freedom; the linear guide assembly drives an external load (9) to perform linear motion, so as to realize a fourth degree of freedom.

2. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 1, characterized in that: The pitch drive system includes a lift (12), a single-degree-of-freedom hinge (2), a lift push rod hinge (3) and a hinge (4); the single-degree-of-freedom hinge (2) is rotatably connected to the frame of the traveling crane trolley body, and the lift push rod hinge (3) is hinged to the circular arc guide rail mounting frame (5); the lift (12) is connected to a lift seat (16) with a gear rack structure on both sides through a lifting bidirectional gear shaft (17), and the lift seat (16) is hinged to the circular arc guide rail mounting frame (5) through a hinge (4); the circular arc guide rail mounting frame (5) is driven to rotate around the single-degree-of-freedom hinge (2) by the extension and retraction of the retractable push rod (15) of the lift seat (16).

3. A four-degree-of-freedom crane trolley with an adjustable motion axis according to claim 1 or 2, characterized in that: The yaw drive system comprises an arc guide rail (6), an arc guide rail mounting frame (5), an arc rack (13) and a yaw drive gear (14); the arc guide rail (6) is fixed to the upper surface of the arc guide rail mounting frame (5), and the arc rack (13) is fixed along the arc profile of the arc guide rail (6); the yaw drive gear (14) is meshed with the arc rack (13), and the yaw drive gear (14) is driven by a yaw drive motor (21); through the meshing transmission of the yaw drive gear (14) and the arc rack (13), the linear guide assembly is driven to rotate around the center of the arc guide rail (6).

4. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 3, characterized in that: The linear guide rail assembly comprises a linear guide rail mounting frame (7), a linear guide rail (8) and a load connection slider; the linear guide rail mounting frame (7) is an internally hollowed frame structure, and its lower surface is fixedly connected to the slider of the arc guide rail (6); the linear guide rail (8) is fixed along the length direction of the linear guide rail mounting frame (7), the load connection slider is slidably matched with the linear guide rail (8), and the load connection slider is fixedly connected to the external load (9).

5. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 4, characterized in that: A driving rack is provided on one side of the linear guide rail (8), and a driving gear meshing with the driving rack is provided on the load connecting slider. The driving gear is driven by an external motor and is used to drive the load connecting slider and the load (9) to move along the linear guide rail (8).

6. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 4, characterized in that: The linear guide rail mounting frame (7) is integrally formed from aluminum alloy.

7. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 2, characterized in that: The telescopic stroke range of the telescopic push rod (15) is 0-100 mm, and the pitch angle adjustment range of the yaw drive system is ±5°.

8. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 1, characterized in that: The load-bearing wheel (10) and the driving wheel (11) are symmetrically mounted on both sides of the vehicle frame, and the driving wheel (11) is connected to an external servo motor via a speed reducer.

9. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 1, characterized in that: The curvature radius of the circular arc guide rail (6) is 800-2000 mm, the module of the yaw drive gear (14) and the circular arc rack (13) is 1-3, and the yaw angle adjustment range of the yaw drive system is ±5°.

10. The four-degree-of-freedom crane trolley with adjustable motion axis according to claim 1, characterized in that: The three-degree-of-freedom guide rail module is integrated with a pitch drive system, a yaw drive system and a linear guide rail assembly, and the three-degree-of-freedom guide rail module is detachably connected to the crane trolley body.

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