A six-degree-of-freedom assembly device for aero-engine rotor docking

Abstract

The present invention belongs to the field of automated assembly technology, and discloses a six-degree-of-freedom assembly device for docking aero-engine rotors, comprising an adjustable fixing fixture, a rolling clamping mechanism, a screw-driven PR conversion swing platform, a transverse movement mechanism, a double scissor-type lifting and pitching mechanism, and an axial docking mechanism. The present invention adopts a six-axis full-servo drive and a combination of multiple degree-of-freedom motion actuators to achieve six-degree-of-freedom attitude adjustment. The present invention adopts a double scissor-type lifting and pitching mechanism to simultaneously meet the requirements of vertical lifting and vertical pitching attitude adjustment, adds a floating guide rail assembly, eliminates motion dead points, and ensures smooth pitching attitude adjustment. The accurate mathematical relationship between the input motor angle and the output lifting height can be simply obtained based on the kinematic model of the scissor-type mechanism, which is convenient for quantitative control. The rolling clamping mechanism of the present invention has a high degree of integration and can simultaneously meet the requirements of part rolling and clamping. The present invention has a compact structure, high six-degree-of-freedom attitude adjustment accuracy, good static stiffness and motion stability, and a high degree of automation.

Description

Technical Field

[0001] The present invention belongs to the technical field of automated assembly, and in particular relates to a six-degree-of-freedom assembly device for docking aircraft engine rotor components. Background Art

[0002] As the heart of an aircraft, the performance of an aircraft engine is directly linked to its flight safety, economy, and reliability. Therefore, manufacturing and assembly precision demands high standards. The final accuracy of an aircraft engine is closely related to initial assembly accuracy. Assembly accuracy, a key performance indicator in the production process, significantly impacts its performance. This is particularly true for the low-pressure turbine, a typical long-shaft component in aircraft engines. Its large aspect ratio, long mating stroke, numerous bolt holes along the sealing edge, and short seams make manual alignment difficult, prone to collision and wear, which can damage critical mating structures like the seams and severely impact component performance. For example, the docking of the low-pressure turbine shaft and the grate disc requires six degrees of freedom (DOF) spatial position adjustment. Negative and frictional conditions are unacceptable, ensuring automatic alignment of the interface, including shaft-disc coaxiality, seam concentricity, and bolt hole alignment. This requires no collision or wear during docking motion. Therefore, the docking equipment must possess high rigidity, motion precision, and flexibility for easy control.

[0003] Today, manual assembly remains the mainstream method in aeroengine manufacturing. The assembly equipment used, for example, has relatively low degrees of freedom and automation, and a low degree of mechanical integration. For example, assembly equipment uses modular structures with column hoisting. These machines can only perform simple linear or rotational movements, requiring high levels of worker skill and being labor-intensive. Repeated trial assembly and measurement can also introduce new errors, making it difficult to maintain production efficiency and assembly accuracy. In recent years, some aeroengine manufacturers and university laboratories have begun researching multi-degree-of-freedom assembly equipment for aeroengine parts.

[0004] Chinese patent CN201420167053.8 discloses a "Multi-degree-of-freedom aircraft engine assembly platform," comprising a lifting device, a pitch drive device, a C-ring drive device, a C-ring device, and a control module. The lifting device is fixedly connected to a foundation; the pitch drive device is slidably connected to the lifting device and has a vertical connection surface; the C-ring drive device is rotatably connected to the vertical connection surface and has a drive gear; the C-ring device includes a C-ring that meshes with the drive gear and rotates about a rotational centerline when the drive gear rotates; and the control module is electrically connected to the lifting device, the pitch drive device, and the C-ring drive device. This device enables universal assembly of engine cores, modules, and complete units, reducing manual labor, requiring a small footprint, and providing excellent safety. However, the assembly platform can only achieve a maximum of three degrees of freedom: vertical lift, pitch within a vertical plane, and roll. It cannot perform docking assembly and requires additional devices to assist in component alignment and assembly. Moreover, the force model of the equipment is cantilever support. The parts, C-ring drive device, C-ring device and control module are all installed in the form of a cantilever on the vertical connection surface of the pitch drive device. The rigidity of this force-bearing structure is poor, and it is easy to cause deformation of the load-bearing structure, resulting in changes in the spatial posture of the parts to be assembled, affecting the assembly accuracy.

[0005] Therefore, if the integration of assembly equipment can be improved, the freedom of movement of the mechanism can be increased, and more sophisticated drive devices can be combined, the assembly accuracy and overall assembly efficiency of aero-engine rotor parts can be improved to better meet production needs. Summary of the Invention

[0006] In view of the problems existing in the above-mentioned prior art, the present invention designs an assembly platform capable of completing six-degree-of-freedom posture adjustment motion, which has a compact structure and is easy to be automatically controlled.

[0007] The technical solution of the present invention:

[0008] A six-degree-of-freedom assembly device for docking aero-engine rotors, comprising an adjustable fixing fixture, a roll clamping mechanism, a screw-driven PR conversion swing platform, a traverse mechanism, a double-scissor lift and pitch mechanism, and an axial docking mechanism;

[0009] The adjustable fixing fixture is used to install disc-shaped parts, and is mainly composed of a "⊥"-shaped support frame, a V-shaped block fixture, a cylindrical support frame, a supporting column and a spiral compression rod; wherein the cylindrical support frame is installed on the vertical surface of the "⊥"-shaped support frame, and its axis is perpendicular to the vertical surface; the V-shaped block fixture is installed on the horizontal bottom surface of the "⊥"-shaped support frame, with the vertical surface as the boundary, and the V-shaped block fixture and the cylindrical support frame are on the same side; the "⊥"-shaped support frame is placed on the workbench below through the supporting column and the spiral compression rod, the supporting column and the cylindrical support frame are on the same side, and the spiral compression rod and the cylindrical support frame are on the opposite side; the disc-shaped part of the aero-engine rotor is a hollow structure, and when in use, the cylindrical support frame is inserted into the hollow structure, and then the V-shaped block fixture is used to support and clamp it, thus completing the clamping, and the spiral compression rod is screwed in or out to slightly adjust the pitch position of the disc-shaped part, which can be fine-tuned in conjunction with a spirit level;

[0010] The rolling clamping mechanism comprises two sets of clamps, each of which is mainly composed of two roller mechanisms and a V-shaped clamping block. The two sets of clamps are arranged in parallel and are used to provide simple support for the long-axis parts. The rolling clamping mechanism has a total of four rollers, one of which is a driving wheel driven by a servo motor, and the other three are driven wheels that play a supporting role. The driving wheel is responsible for driving the long-axis parts to roll and adjust their posture. After the roll adjustment is completed, the V-shaped clamping block can be clamped. In addition, an axial stop rod is installed on one set of clamps to prevent the long-axis parts from axial movement.

[0011] The screw-driven PR conversion swing platform is mainly composed of a linear guide slider pair I, a screw nut pair I, a T-shaped connecting plate, a swing floating guide group, an arc guide slider group, a bearing, a swing platform and a swing platform base, and is driven by a servo motor; the swing platform is installed on the swing platform base through the arc guide slider group and the bearing, one end is supported by the arc guide slider group, and the other end is supported by the bearing; at the lower edge of the swing platform on one side of the arc guide slider group, the swing floating guide group is suspended on the swing platform in a cantilever manner by bolts. Below the swing platform; the screw nut pair I is connected to the swing platform via a T-shaped connecting plate and a swing floating guide assembly. The T-shaped connecting plate is fixed to the screw nut pair I and the linear guide slider pair I, and is hinged to the swing floating guide assembly. The motor drives the screw, and the swing floating guide assembly converts the linear motion of the nut in the screw nut pair I into rotation of the swing platform with the bearing as the axis. The screw drives the PR conversion swing platform to increase the distance between the rotation center of the screw nut pair I and the axis of the bearing to increase the swing attitude adjustment accuracy.

[0012] The transverse movement mechanism is mainly composed of a screw nut pair II, a linear guide slider pair II and a mechanism base, and is driven by a servo motor; the screw drives the PR conversion swing platform to be connected to the transverse movement mechanism base through the screw nut pair II and the linear guide slider pair II, and the servo motor drives the screw to achieve horizontal transverse movement and posture adjustment of the parts;

[0013] The double-scissor-type lifting and pitching mechanism is mainly composed of two scissor-type mechanisms, a pitch floating guide rail group, a lifting and pitching mounting platform and a lifting and pitching mechanism chassis, and is driven by dual servo motors. It is a 2-degree-of-freedom motion mechanism; the base of the transverse movement mechanism is installed on the lifting and pitching mounting platform; below the lifting and pitching mounting platform, one side is installed on the inverted pitch floating guide rail group, and the guide rail slider thereon is installed with a bearing seat I, through which the support shaft I passes, and the two ends of the support shaft I are supported by bearing seats II; the installation form of the other side is similar to the above, lacking the pitch floating guide rail group, and the bearing seat II is directly installed on the lower surface of the lifting and pitching mounting platform; the lifting and pitching mounting platform is connected to the two scissor-type mechanisms below through the pitch floating guide rail group, the support shaft I, the support shaft III, the bearing seat I and the bearing seat II; the two scissor-type mechanisms are installed on the lifting and pitching mechanism chassis, and can realize vertical lifting when operated synchronously, and can realize pitching movement in the vertical plane when operated asynchronously;

[0014] The two scissor fork mechanisms have the same structural form, mainly consisting of a linear guide slider pair III, a screw nut pair III, a scissor fork plate, a support shaft II, a bearing seat, a screw nut connecting plate and an upper plate of the scissor fork mechanism, and are driven by a servo motor; the two scissor fork plates form a pair, each of which has a circular through hole at both ends, which cooperates with the support shaft II and is tightened and fixed by a round nut and a stop washer. A hole is opened in the middle of the plate to install a pin shaft. A pair of scissor fork plates uses one pin shaft to ensure that the upper plate of the scissor fork mechanism is in a horizontal state during movement; the forks on both sides of the scissor fork mechanism are divided into a floating side and a fixed side: The fork legs on the floating side can move along with the linear guide slider pair III. The servo motor on this side is connected to the screw nut pair III. The screw nut connecting plate is installed on the nut bracket of the screw nut pair III and is connected to the linear guide slider pair III. Bearing seats are installed on both sides of the screw nut connecting plate, which simply supports the support shaft II. The shear fork plate passes through the shaft, and the axial position of the shear fork plate is fixed with round nuts and lock washers. There is no guide rail on the fixed side, and the fork legs cannot be displaced. The bearing seat III is directly installed on the lifting and pitching mechanism chassis, which simply supports the support shaft II and is used to install the fork legs of the shear fork plate.

[0015] The axial docking mechanism is mainly composed of a linear guide slider pair IV, a screw nut pair IV and a mounting base, and is driven by a servo motor; the guide rail of the linear guide slider pair IV is installed on the mounting base through a guide rail positioning seat, and the slider carries a double scissor-type lifting and pitching mechanism chassis. The servo motor is connected to the screw nut pair IV to drive the upper parts to move linearly relative to the base to achieve axial docking.

[0016] Beneficial effects of the present invention:

[0017] 1. The double-scissor-type lifting and pitching mechanism of the present invention can simultaneously meet the requirements of vertical lifting and vertical pitch adjustment, with high mechanism integration and good structural stability. The addition of a pitch floating guide rail group can eliminate motion dead points and ensure smooth pitch adjustment. The kinematic model of the scissor-type mechanism is simple, and an accurate mathematical relationship between the input motor rotation angle and the output lifting height can be obtained, which facilitates quantitative control.

[0018] 2. The rolling and clamping mechanism of the present invention has a high degree of integration and can simultaneously meet the needs of part rolling and clamping.

[0019] 3. The screw-driven PR conversion swing platform of the present invention improves the accuracy of swing posture adjustment by increasing the distance between the rotation center and the input motion position.

[0020] 4. The present invention adopts six-axis full servo drive and a combination of multiple degrees of freedom motion actuators, which has a high degree of automation, improves assembly efficiency, ensures stable assembly quality, and reduces labor intensity of workers.

[0021] 5. The present invention adopts a completely mechanical structural design, which has a compact structure, high posture adjustment accuracy, good static rigidity and motion stability, and is convenient for the integrated installation and transportation of the whole machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0023] Figure 2 It is an exploded view of the posture adjustment mechanism of each layer of the present invention.

[0024] Figure 3 Schematic diagram of the adjustable clamp.

[0025] Figure 4 This is a layered diagram of the double scissor-type lifting and pitching mechanism.

[0026] Figure 5 This is a specific implementation case of a six-degree-of-freedom assembly device used for aero-engine rotor docking.

[0027] In the figure: 1. V-shaped clamping block, 2. Roller, 3. Axial stopper, 4. Swing platform, 5. Swing floating guide rail assembly, 6. T-shaped connecting plate, 7. Linear guide slider pair I, 8. Screw nut pair I, 9. Arc guide slider assembly, 10. Swing platform base, 11. Linear guide slider pair II, 12. Screw nut pair II, 13. Transverse mechanism base, 14. Pitch floating guide rail assembly, 15. Bearing seat I, 16. Support shaft I, 17. Bearing seat II, 18. Shear fork plate, 19. Bearing seat III, 20. Support shaft II, 21. Lifting and pitching mechanism chassis, 22. Bearing seat IV, 23. Mounting base, 24. Linear guide slider pair IV, 25. Screw nut pair IV, 26. Linear guide slider pair III, 27. Screw nut connecting plate, 28. Screw nut pair III, 29. Scissor mechanism upper plate, 30. Support shaft III, 31. Lifting and pitching mounting platform, 32. Bearing, 33. Rolling clamping mechanism, 34. Screw-driven PR conversion swing platform, 35. Transverse movement mechanism, 36. Double scissor-type lifting and pitching mechanism, 37. Axial docking mechanism, 38. Adjustable fixing fixture, 39. "⊥"-shaped support frame, 40. V-shaped block fixture, 41. Cylindrical support frame, 42. Support column, 43. Screw clamping rod. DETAILED DESCRIPTION

[0028] The specific implementation of the present invention is described in detail below in conjunction with the technical solutions and drawings.

[0029] like Figure 1-4 As shown, a six-degree-of-freedom assembly device for docking aero-engine rotors includes a roll clamping mechanism 33, a screw-driven PR conversion swing platform 34, a transverse movement mechanism 35, a double-scissor-type lifting and pitching mechanism 36, an axial docking mechanism 37, and an adjustable fixing fixture 38.

[0030] The rolling clamping mechanism 33 is used to clamp the long-axis parts. The servo motor drives the active roller 2 to drive the long-axis parts to roll. After the posture adjustment is completed, the V-shaped clamping block 1 is clamped using bolts.

[0031] The screw drives the PR conversion swing platform 34, and the servo motor drives the screw nut pair I6, which converts the linear motion into swinging motion around the bearing 32 through the swing floating guide rail group 5.

[0032] The lateral movement mechanism 35 is driven by a servo motor to drive the screw nut pair II 12 to drive the upper component to perform lateral movement and posture adjustment.

[0033] The double scissor lift and pitch mechanism 36 has dual servo motors driving the screw nut pair III 28. The two sets of scissors have the same motion form. When the servo motors are driven synchronously, vertical lifting can be achieved. When driven asynchronously, pitching motion in the vertical plane can be achieved.

[0034] The axial docking mechanism 37 is driven by a servo motor to drive the screw nut pair IV 25 to drive the upper components to perform axial docking.

[0035] The adjustable fixing clamp 38 is used to fix and clamp the disc-shaped parts. The disc-shaped parts of the aero-engine rotor are hollow structures. When in use, the cylindrical support frame 41 is inserted into the hollow shaft, and then the V-shaped block clamp 40 is used to support and clamp to complete the clamping. The spiral clamping rod 43 can be screwed in or out to slightly adjust the pitch position of the part, and can be fine-tuned in conjunction with a spirit level.

[0036] The method of use of the present invention is:

[0037] The first step is to place the entire device on a flat, level ground or workbench, clamp the shaft and disc parts that need to be assembled, clamp the disc parts firmly, and slightly adjust the levelness.

[0038] In the second step, the servo motor drives the lead screw to drive the PR conversion swing platform 34 and the floating side scissors of the double scissors-type lifting and pitching mechanism 36 so that the docking interfaces are parallel to each other.

[0039] The third step is to synchronously drive the two sets of scissors of the double-scissor-type lifting and pitching mechanism 36 so that the two axis centers of the shaft disc are at the same height.

[0040] The fourth step is to drive the transverse movement mechanism 35 so that the axes of the parts on both sides are collinear.

[0041] The fifth step is to drive the roller 2 of the rolling clamping mechanism 33 so that the centers of the bolt holes on the sealing side are aligned, and then clamp the V-shaped clamping block 1.

[0042] Step 6: Drive the axial docking mechanism 37 to complete the docking of the rotor parts.

[0043] The present invention is not limited to this embodiment, and any equivalent concepts or modifications within the technical scope disclosed by the present invention are included in the protection scope of the present invention.

Claims

1. A six-degree-of-freedom assembly device for aero-engine rotor docking, characterized in that: The six-degree-of-freedom assembly equipment includes an adjustable fixing fixture, a rolling clamping mechanism, a screw-driven PR conversion swing platform, a traverse mechanism, a double-scissor-type lifting and pitching mechanism, and an axial docking mechanism; The adjustable fixing fixture is used to install disc-shaped parts, and is mainly composed of a "⊥"-shaped support frame, a V-shaped block fixture, a cylindrical support frame, a supporting column and a spiral compression rod; wherein the cylindrical support frame is installed on the vertical surface of the "⊥"-shaped support frame, and its axis is perpendicular to the vertical surface; the V-shaped block fixture is installed on the horizontal bottom surface of the "⊥"-shaped support frame, with the vertical surface as the boundary, and the V-shaped block fixture and the cylindrical support frame are on the same side; the "⊥"-shaped support frame is placed on the lower workbench through the supporting column and the spiral compression rod, the supporting column and the cylindrical support frame are on the same side, and the spiral compression rod and the cylindrical support frame are on the opposite side; the disc-shaped part of the aero-engine rotor is a hollow structure. When in use, the cylindrical support frame is inserted into the hollow structure, and then the V-shaped block fixture is used to support and clamp it, thus completing the clamping, and the spiral compression rod is screwed in or out to slightly adjust the pitch position of the disc-shaped part, which can be fine-tuned in conjunction with a spirit level; The rolling clamping mechanism comprises two sets of clamps, each of which is mainly composed of two roller mechanisms and a V-shaped clamping block. The two sets of clamps are arranged in parallel and are used to provide simple support for the long-axis parts. The rolling clamping mechanism has a total of four rollers, one of which is a driving wheel driven by a servo motor, and the other three are driven wheels that play a supporting role. The driving wheel is responsible for driving the long-axis parts to roll and adjust their posture. After the roll adjustment is completed, the V-shaped clamping block can be clamped. In addition, an axial stop rod is installed on one set of clamps to prevent the long-axis parts from axial movement. The screw-driven PR conversion swing platform is mainly composed of a linear guide slider pair I, a screw nut pair I, a T-shaped connecting plate, a swing floating guide group, an arc guide slider group, a bearing, a swing platform and a swing platform base, and is driven by a servo motor; the swing platform is installed on the swing platform base through the arc guide slider group and the bearing, one end is supported by the arc guide slider group, and the other end is supported by the bearing; at the lower edge of the swing platform on one side of the arc guide slider group, the swing floating guide group is suspended on the swing platform in a cantilever manner by bolts. Below the swing platform; the screw nut pair I is connected to the swing platform via a T-shaped connecting plate and a swing floating guide assembly. The T-shaped connecting plate is fixed to the screw nut pair I and the linear guide slider pair I, and is hinged to the swing floating guide assembly. The motor drives the screw, and the swing floating guide assembly converts the linear motion of the nut in the screw nut pair I into rotation of the swing platform with the bearing as the axis. The screw drives the PR conversion swing platform to increase the distance between the rotation center of the screw nut pair I and the axis of the bearing to increase the swing attitude adjustment accuracy. The transverse movement mechanism is mainly composed of a screw nut pair II, a linear guide slider pair II and a mechanism base, and is driven by a servo motor; the screw drives the PR conversion swing platform to be connected to the transverse movement mechanism base through the screw nut pair II and the linear guide slider pair II, and the servo motor drives the screw to achieve horizontal transverse movement and posture adjustment of the parts; The double-scissor-type lifting and pitching mechanism is mainly composed of two scissor-type mechanisms, a pitch floating guide rail group, a lifting and pitching mounting platform and a lifting and pitching mechanism chassis, and is driven by dual servo motors. It is a 2-degree-of-freedom motion mechanism; the base of the transverse movement mechanism is installed on the lifting and pitching mounting platform; below the lifting and pitching mounting platform, one side is installed on the inverted pitch floating guide rail group, and the guide rail slider thereon is installed with a bearing seat I, through which the support shaft I passes, and the two ends of the support shaft I are supported by bearing seats II; the installation form of the other side is similar to the above, lacking the pitch floating guide rail group, and the bearing seat II is directly installed on the lower surface of the lifting and pitching mounting platform; the lifting and pitching mounting platform is connected to the two scissor-type mechanisms below through the pitch floating guide rail group, the support shaft I, the support shaft III, the bearing seat I and the bearing seat II; the two scissor-type mechanisms are installed on the lifting and pitching mechanism chassis, and can realize vertical lifting when operated synchronously, and can realize pitching movement in the vertical plane when operated asynchronously; The two scissor fork mechanisms have the same structural form, mainly consisting of a linear guide slider pair III, a screw nut pair III, a scissor fork plate, a support shaft II, a bearing seat, a screw nut connecting plate and an upper plate of the scissor fork mechanism, and are driven by a servo motor; the two scissor fork plates form a pair, and a circular through hole is punched at each end of the scissor fork plate, which cooperates with the support shaft II and is tightened and fixed by a round nut and a stop washer. A hole is opened in the middle of the scissor fork plate to install a pin shaft, and a pair of scissor fork plates uses one pin shaft to ensure that the upper plate of the scissor fork mechanism is in a horizontal state during movement; the fork legs on both sides of the scissor fork mechanism are divided into a floating side and a fixed side : The fork legs on the floating side can move along with the linear guide slider pair III. The servo motor on this side is connected to the screw nut pair III. The screw nut connecting plate is installed on the nut bracket of the screw nut pair III and is connected to the linear guide slider pair III. Bearing seats are installed on both sides of the screw nut connecting plate, which simply supports the support shaft II. The shear fork plate passes through the shaft, and the axial position of the shear fork plate is fixed with round nuts and lock washers; there is no guide rail on the fixed side, and the fork legs cannot be displaced. The bearing seat III is directly installed on the chassis of the lifting and pitching mechanism, and simply supports the support shaft II for installing the fork legs of the shear fork plate; The axial docking mechanism is mainly composed of a linear guide slider pair IV, a screw nut pair IV and a mounting base, and is driven by a servo motor; the guide rail of the linear guide slider pair IV is installed on the mounting base through a guide rail positioning seat, and the slider carries a double scissor-type lifting and pitching mechanism chassis. The servo motor is connected to the screw nut pair IV to drive the upper parts to move linearly relative to the mounting base to achieve axial docking.

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