Machining device and machining method
By using the adaptive control of the floating platform, ball joint connection mechanism, and triaxial force sensor, the problems of clamping deformation and chatter under traditional clamping methods are solved, and high-precision machining of thin-walled parts is achieved.
Patent Information
- Application Number
- CN202511915963.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-18
- Publication Date
- 2026-01-23
AI Technical Summary
Traditional rigid clamping methods are prone to clamping deformation, chatter, and residual stress when machining thin-walled complex parts, affecting machining accuracy and consistency.
A machining device that combines a floating platform with a ball joint connection mechanism, a triaxial force sensor, and a magnetorheological fluid damper fixes the workpiece by vacuum adsorption and uses a multi-stage adaptive control method to monitor and suppress flutter and release stress in real time.
It effectively avoids clamping deformation and residual stress, improves the geometric accuracy and machining consistency of thin-walled parts, and enhances the dynamic stability and quality of the machining process.
Smart Images
Figure CN121374232A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of mechanical processing, in particular to a mechanical processing device and a processing method. BACKGROUND
[0002] In the fields of aerospace, energy equipment, etc., the demand for thin-walled complex parts made of difficult-to-machine materials such as titanium alloy and high-temperature alloy is increasing. Such parts have the characteristics of thin wall thickness (usually <1mm) and extremely low rigidity, and are prone to the following problems under traditional rigid clamping conditions: 1. Clamping deformation: the local pressure applied by the rigid clamp easily causes elastic deformation of the workpiece, which will rebound after unloading, causing the geometric accuracy of the workpiece to be out of tolerance; 2. Workpiece vibration during processing: the traditional rigid clamp cannot compensate dynamically and lacks depth coupling with the processing process, affecting the processing consistency and thus the processing accuracy; 3. Residual stress influence: the clamping stress of the traditional rigid clamping is not completely released during finishing, resulting in distortion of the final profile of the part.
[0003] Therefore, the present application mainly researches and improves the above technical problems. SUMMARY
[0004] In view of the existing technical problems, the present application provides a mechanical processing device and a processing method to solve the problems in the prior art.
[0005] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions: A mechanical processing device, comprising a device body, a rotating table is arranged on the device body, and a tool clamp is arranged on the rotating table; The tool clamp comprises a mounting table, the mounting table is connected with a floating platform through a spherical hinge connecting mechanism, the plane where the floating platform is located is parallel to the horizontal plane, a vacuum chuck is arranged at the center position of the floating platform, a plurality of three-way force sensors are arranged on the floating platform, the three-way force sensors are uniformly distributed along the circumference of the vacuum chuck, at least one set of first vibration suppression mechanisms is arranged on the mounting table, the first vibration suppression mechanisms are respectively connected with the floating platform, and the first vibration suppression mechanisms can suppress the vibration generated during the processing of the workpiece. A central controller is arranged on the mounting table, and the three-way force sensors and the first vibration suppression mechanisms are respectively electrically connected with the central controller.
[0006] Preferably, two sets of the first vibration suppression mechanisms are arranged on the mounting table, and the two sets of the first vibration suppression mechanisms are respectively arranged along the X direction and the Y direction of the mounting table.
[0007] Preferably, the first chatter suppression mechanism comprises a first low-friction air cylinder and a first magneto-rheological fluid damper arranged in a horizontal direction, and the same end of the first low-friction air cylinder and the first magneto-rheological fluid damper is connected to the mounting table, and the other end is connected to a connecting plate, and the connecting plate is fixed to the floating platform.
[0008] Preferably, a support is arranged on the mounting table near the first chatter suppression mechanism, and the same end of the first low-friction air cylinder and the first magneto-rheological fluid damper is connected to the support.
[0009] Preferably, the ball joint connecting mechanism comprises a ball joint seat arranged on the mounting table, the ball joint seat is in a hollow hemispherical structure, a ball bearing support frame is arranged in the ball joint seat, a ball bearing is arranged on the ball bearing support frame, the ball bearing support frame limits the rotation freedom degree of the ball bearing, the upper end of the ball bearing extends out of the ball joint seat, and the part of the ball bearing extending out of the ball joint seat is embedded in the floating platform, so as to realize the connection between the ball bearing and the floating platform.
[0010] Preferably, the ball bearing support frame comprises a base, and three support wings are uniformly distributed along the circumference of the base, the support wings are in an arc structure, and the ball bearing is supported on the three support wings. A disc spring is arranged in the ball joint seat corresponding to the position of each support wing, and the outer side of each support wing is connected to the disc spring at the corresponding position.
[0011] Preferably, a groove is arranged on the inner side of the support wing along the length direction of the support wing, a plurality of cross rollers are arranged in the groove along the length direction of the groove, and the ball bearing is supported on the cross rollers.
[0012] Preferably, a second chatter suppression mechanism electrically connected to the central controller is arranged on the mounting table, the second chatter suppression mechanism comprises a second low-friction air cylinder and a second magneto-rheological fluid damper arranged in a Z direction, the lower end of the second low-friction air cylinder and the second magneto-rheological fluid damper is connected to the mounting table, and the upper end is connected to a support plate, and the ball joint seat is fixed to the support plate.
[0013] A machining method using the machining device, specifically comprising the following main steps: Step 1: workpiece clamping and system initialization Place the workpiece to be processed on the vacuum chuck of the floating platform, so that the workpiece to be processed is fixed by the vacuum chuck; the central controller calls the preset processing process parameters according to the input workpiece material and geometric feature information, controls the air pressure of the first low-friction air cylinder and the second low-friction air cylinder to drop to a first preset low pressure value, and simultaneously closes the excitation current of the first magneto-rheological fluid damper and the second magneto-rheological fluid damper, so that the system is in a low stiffness / low damping mode, and the workpiece is naturally positioned without additional mechanical clamping stress; Step two: adaptive multi-stage processing process control Coarse machining stage: the three-way force sensor monitors the stress state of the workpiece in real time, and when the stress in any direction is detected to exceed a first threshold value, the central controller controls the air pressure of the first low-friction air cylinder or the second low-friction air cylinder in the corresponding direction and the associated direction to rise to a second preset high pressure value, simultaneously connects the first preset excitation current to the first magneto-rheological fluid damper or the second magneto-rheological fluid damper, so that the system switches to a high stiffness / high damping mode to effectively suppress cutting vibration; the first threshold value is the stress threshold value in the coarse machining state; Fine machining stage: after coarse machining is completed, the central controller switches the system back to the low stiffness / low damping mode: the air pressure of the first low-friction air cylinder or the second low-friction air cylinder is reduced to a third preset low pressure value, and the excitation current of the first magneto-rheological fluid damper or the second magneto-rheological fluid damper is significantly reduced or closed, so as to actively release the residual stress accumulated by the workpiece in the coarse machining; Step three: processing completion and system reset After fine machining is completed, first, the vacuum system of the vacuum chuck is closed, then the air pressure of the first low-friction air cylinder and the second low-friction air cylinder is released, and the excitation current of the first magneto-rheological fluid damper and the second magneto-rheological fluid damper is closed, under the action of the spherical hinge connecting mechanism, the floating platform automatically returns to the initial position, the machined workpiece is removed, and the next clamping cycle is waited to be performed.
[0014] Compared with the prior art, the beneficial effects of the present application are: 1. Only vacuum adsorption is relied on to realize workpiece fixation during clamping, so that local clamping elastic deformation and clamping stress caused by rigid clamping are fundamentally eliminated, the system stiffness is actively released before fine machining, so that the workpiece completes machining in a state close to zero additional stress, and the final profile distortion caused by residual stress release is effectively avoided, and the geometric precision and dimensional stability of the thin-walled part are significantly improved; 2. Through the cooperative control of the three-direction chatter suppression mechanisms, high stiffness and high damping are used in coarse machining to suppress vibration and ensure stability, and low stiffness and low damping are used in fine machining to release stress and ensure precision, so that the adaptive capability effectively solves the dynamic compensation mechanism in the machining of the thin-walled part, and effectively improves the machining precision of the workpiece; 3. Based on the real-time monitoring of the triaxial force sensor and the millisecond-level response characteristics of the magnetorheological fluid damper, the system can instantly sense and suppress sudden cutting chatter or impact, suppressing high-frequency fluctuations in cutting force and instantaneous deformation of the workpiece in the bud, greatly improving the dynamic stability and processing quality of the machining process. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 for Figure 1 A schematic diagram of the fixture in the diagram; Figure 3 for Figure 2 A schematic diagram of the structure after removing the floating platform; Figure 4 for Figure 3 A schematic diagram of the ball joint connection mechanism in the diagram; Figure 5 for Figure 4 A schematic diagram of the structure after removing the beads; Figure 6 for Figure 5 A schematic diagram of the ball support frame. Detailed Implementation
[0016] The present invention will be further described in detail below with reference to experimental examples and specific embodiments. However, this should not be construed as limiting the scope of the above-mentioned subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.
[0017] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.
[0018] As attached Figure 1 - Appendix Figure 6 The machine tool shown includes a main body 1, a rotary table 2 mounted on the main body 1, and tooling fixtures mounted on the rotary table 2. The main body 1 can be a conventional CNC machine tool or a five-axis machining center.
[0019] For details, please refer to the following: Figure 2 and Figure 3The tooling fixture comprises a mounting table 3 connected with a floating platform 5 through a ball hinge connecting mechanism, the plane where the floating platform 5 is located is parallel to the horizontal plane, the central position of the floating platform 5 is provided with a vacuum chuck 51, the vacuum chuck 51 is connected with a vacuum system to control the suction force of the vacuum chuck, a plurality of three-way force sensors 52 are arranged on the floating platform 5, the three-way force sensors 52 are uniformly distributed along the circumference of the vacuum chuck 51, two groups of the first chatter suppression mechanisms are arranged on the mounting table 3, and the two groups of the first chatter suppression mechanisms are arranged along the X direction and the Y direction of the mounting table 3 respectively. The second chatter suppression mechanism is also arranged on the mounting table 3, and the second chatter suppression mechanism is arranged along the Z direction, and the first chatter suppression mechanism and the second chatter suppression mechanism are connected with the floating platform 5 respectively to suppress the chatter generated in the workpiece machining process.
[0020] The mounting table 3 is provided with a central controller 8, the three-way force sensors 52 and the first chatter suppression mechanism and the second chatter mechanism are electrically connected with the central controller 8 respectively, and the first chatter suppression mechanism and the second chatter mechanism are controlled by the central controller 8 to adjust the action to suppress the chatter generated in the machining process.
[0021] The first chatter suppression mechanism comprises a first low-friction air cylinder 61 and a first magnetorheological fluid damper 62 arranged along the horizontal direction, the same end of the first low-friction air cylinder 61 and the first magnetorheological fluid damper 62 is connected on the mounting table 3, the other end is connected with a connecting plate 63, and the connecting plate 63 is fixed on the floating platform 5.
[0022] Specifically, two supports 31 are arranged on the mounting table 3 close to the first chatter suppression mechanism, the same end of the first low-friction air cylinder 61 and the first magnetorheological fluid damper 62 in the X direction is connected on the support 31 in the X direction, and the same end of the first low-friction air cylinder 61 and the first magnetorheological fluid damper 62 in the Y direction is connected on the support 31 in the Y direction.
[0023] The second chatter suppression mechanism comprises a second low-friction air cylinder 71 and a second magnetorheological fluid damper 72 arranged along the Z direction, the lower end of the second low-friction air cylinder 71 and the second magnetorheological fluid damper 72 is connected on the mounting table 3, and the upper end is connected with a support plate 73, and the ball hinge seat 41 of the ball hinge connecting mechanism is fixed on the support plate 73.
[0024] Reference Figure 4 , Figure 5 and Figure 6The ball joint connection mechanism includes a ball joint seat 41 embedded in the support plate 73. The ball joint seat 41 is fixedly connected to the support plate 73. The ball joint seat 41 has a hollow hemispherical structure. A ball ball support frame 44 is floating inside the ball joint seat 41. A ball ball 45 is provided on the ball ball support frame 44. The ball ball support frame 44 can restrict all rotational degrees of freedom of the ball ball 45, so that the ball ball 45 and the ball ball support frame 44 float synchronously along the ball joint seat 41. The upper end of the ball ball 45 extends out of the ball joint seat 41, and the part of the ball ball 45 extending out of the ball joint seat 41 is embedded in the floating platform 5, thereby realizing the fixed connection between the ball ball 45 and the floating platform 5.
[0025] The ball bearing support frame 44 includes a base 441 with three support wings 442 evenly distributed circumferentially. The support wings 442 have an arc-shaped structure that matches the arc shape inside the ball joint seat 41. The ball bearing 45 is supported on the inner side of the three support wings 442. Inside the ball joint seat 41, three disc springs 43 are evenly distributed circumferentially, corresponding to the positions of each support wing 442 within the ball joint seat 41. The outer sides of the three support wings 442 are connected to the corresponding disc springs 43. A pressure plate 42 is provided inside the ball joint seat 41 corresponding to each disc spring 43. One end of each disc spring 43 is connected to the inner side of the ball joint seat 41 via the pressure plate 42, and the other end is connected to the corresponding support wing 442. The presence of the disc springs 43 ensures that the ball bearing support frame 44, along with the ball bearing 45, can only float in the direction of extension and retraction of the disc springs 43. Three disc springs 43 are evenly distributed inside the ball joint seat 41. The base 441 is located at the bottom of the ball joint seat 41. The outer sides of the three support wings 442 are connected to the corresponding disc springs 43. When the force in a certain direction changes abruptly during the processing, the disc springs 43 in the corresponding range will be compressed or extended. When the workpiece and the force are removed, the ball ball support frame 44, together with the ball ball 45, can drive the floating platform 5 to return to its correct position under the action of the elastic force of the three disc springs 43.
[0026] The inner side of the support wing 442 is provided with a groove 443 along its length direction. Cross rollers 444 are distributed in the groove 443 along its length direction. The ball 45 is supported on the cross rollers 444. The cross rollers 444 can lock all rotational degrees of freedom of the ball 45, so that the ball 45 can only float in the ball joint seat 41 with the ball support frame 44.
[0027] A machining method, employing Figures 1-6 The machining apparatus shown integrates the entire process of clamping, roughing, and finishing into a multimodal adaptive control flow. Through a closed loop of monitoring, judgment, and execution, it achieves on-demand dynamic adjustment of the dynamic characteristics of the machining process. Specifically, it includes the following main steps: Step one: Workpiece clamping and system initialization Place the workpiece to be processed on the vacuum chuck 51 of the floating platform 5, start the adsorption system of the vacuum chuck 51, and fix the workpiece to be processed by the vacuum chuck 51; the central controller 8 calls the preset processing process parameters according to the input workpiece material and geometric feature information, controls the air pressure of the first low-friction air cylinder 61 and the second low-friction air cylinder 71 to decrease to a first preset low pressure value (such as 0.1-0.15 MPa), and at the same time, closes the excitation current of the first magneto-rheological fluid damper 62 and the second magneto-rheological fluid damper 72, at this time, the system is in a low stiffness / low damping mode, and the workpiece is naturally positioned without additional mechanical clamping stress; Step two: Adaptive multi-stage processing process control The processing process system automatically adjusts the support stiffness and damping strength according to real-time feedback; Rough machining stage: the three-way force sensor 52 monitors the stress state of the workpiece in real time, and the three-way force sensor 52 can monitor the stress state of the workpiece in X / Y / Z directions, when the stress in any direction is monitored to exceed a first threshold value, the central controller 8 controls the air pressure of the first low-friction air cylinder 61 or the second low-friction air cylinder 71 in the corresponding direction and the associated direction to increase to a second preset high pressure value (such as 0.4-0.5 MPa), and at the same time, the first magneto-rheological fluid damper 62 or the second magneto-rheological fluid damper 72 is connected to the first preset excitation current (such as 0.8-1.0 T), so that the system is switched to a high stiffness / high damping mode to effectively suppress cutting vibration; the first threshold value is the stress threshold value of each direction in the rough machining state; Fine machining stage: after rough machining is completed, the central controller 8 switches the system back to a low stiffness / low damping mode: specifically, the air pressure of the first low-friction air cylinder 61 or the second low-friction air cylinder 71 is decreased to a third preset low pressure value, and the excitation current of the first magneto-rheological fluid damper 62 or the second magneto-rheological fluid damper 72 is significantly reduced or closed, the residual stress accumulated in the workpiece during rough machining is actively released, and the workpiece is machined in a near-zero stress constraint state to ensure geometric accuracy; Active vibration suppression in milliseconds (throughout the rough and fine machining process): at any stage of machining, the three-way force sensor 52 continuously monitors the high-frequency dynamics of the cutting force, and when the cutting force is monitored to have high-frequency fluctuations and the amplitude exceeds the preset amplitude of the stable cutting amplitude, it is determined to be a sudden chatter, the central controller 8 responds within milliseconds (for example, ≤5 ms), and immediately outputs a high-intensity transient excitation current command to the first magneto-rheological fluid damper 62 and / or the second magneto-rheological fluid damper 72, so that the damping characteristics of the first magneto-rheological fluid damper 62 and / or the second magneto-rheological fluid damper 72 increase sharply in a very short time, actively absorb vibration energy, quickly suppress the chatter, and control the amplitude of the chatter within a very small range (for example, ≤0.01 mm); Step three: processing completion and system reset After finishing the finishing, first, the vacuum system of the vacuum chuck 51 is closed, then, the air pressure of the first low-friction air cylinder 61 and the second low-friction air cylinder 71 is released, the exciting current of the first magnetorheological fluid damper 62 and the second magnetorheological fluid damper 72 is closed, under the reset action of the disc spring 43 of the spherical hinge connecting mechanism, the floating platform 5 automatically returns to the initial position, the processed workpiece is removed, and the next clamping cycle is waited to be performed.
[0028] The preferred embodiments of the present application are described above. It should be understood that those of ordinary skill in the art can make many modifications and variations without departing from the concept of the present application. Therefore, any technical solutions obtained by logical analysis, reasoning or limited experiments based on the prior art according to the concept of the present application should be within the protection scope defined by the claims.
Claims
1. A machining device comprising a device body (1) on which a rotary table (2) is provided, characterized in that: A tool clamp is arranged on the rotating table (2); The tool clamp comprises a mounting table (3), the mounting table (3) is connected with a floating platform (5) through a spherical hinge connecting mechanism, the plane where the floating platform (5) is located is parallel to the horizontal plane, a vacuum chuck (51) is arranged at the center position of the floating platform (5), a plurality of three-way force sensors (52) are arranged on the floating platform (5), the three-way force sensors (52) are uniformly distributed along the circumference of the vacuum chuck (51), at least one set of first chatter suppression mechanisms is arranged on the mounting table (3), the first chatter suppression mechanisms are connected with the floating platform (5), and the first chatter suppression mechanisms can suppress the chatter generated in the workpiece machining process. A central controller (8) is arranged on the mounting table (3), and the three-way force sensors (52) and the first chatter suppression mechanisms are electrically connected with the central controller (8).
2. A machine tool according to claim 1, characterised in that: Two sets of the first chatter suppression mechanisms are arranged on the mounting table (3), and the two sets of the first chatter suppression mechanisms are arranged along the X direction and the Y direction of the mounting table (3) respectively.
3. A machine tool according to claim 2, wherein: The first chatter suppression mechanism comprises a first low-friction air cylinder (61) and a first magnetorheological fluid damper (62) arranged in the horizontal direction, one end of the first low-friction air cylinder (61) and the first magnetorheological fluid damper (62) is connected to the mounting table (3), the other end is connected to a connecting plate (63), and the connecting plate (63) is fixed to the floating platform (5).
4. A machine tool according to claim 3, wherein: A support (31) is arranged on the mounting table (3) close to the first chatter suppression mechanism, and one end of the first low-friction air cylinder (61) and the first magnetorheological fluid damper (62) is connected to the support (31).
5. A machine tool according to claim 3, wherein: The spherical hinge connecting mechanism comprises a spherical hinge seat (41) arranged on the mounting table (3), the spherical hinge seat (41) is in a hollow hemispherical structure, a ball support frame (44) is arranged in the spherical hinge seat (41) in a floating manner, a ball (45) is arranged on the ball support frame (44), the ball support frame (44) limits the rotation freedom degree of the ball (45), the upper end of the ball (45) extends out of the spherical hinge seat (41), and the part of the ball (45) extending out of the spherical hinge seat (41) is embedded in the floating platform (5), so that the ball (45) is connected with the floating platform (5).
6. A machine tool according to claim 5, wherein: The ball support frame (44) comprises a base (441), three support wings (442) are uniformly distributed along the circumference of the base (441), the support wings (442) are in an arc structure, and the ball (45) is supported on the three support wings (442); A disc spring (43) is arranged in the spherical hinge seat (41) corresponding to the position of each support wing (442), and the outer sides of the three support wings (442) are respectively connected with the disc springs (43) at the corresponding positions.
7. A machine tool according to claim 6, wherein: The inner side of the support wing (442) is provided with a groove (443) along the length direction, and a plurality of cross rollers (444) are arranged in the groove (443) along the length direction, and the ball (45) is supported on the cross roller (444).
8. A machine tool according to claim 7, wherein: The mounting table (3) is provided with a second chatter suppression mechanism electrically connected with the central controller (8), the second chatter suppression mechanism comprises a second low-friction air cylinder (71) and a second magnetorheological fluid damper (72) arranged along the Z direction, the lower ends of the second low-friction air cylinder (71) and the second magnetorheological fluid damper (72) are connected on the mounting table (3), the upper ends are connected with a support plate (73), and the spherical hinge base (41) is fixed on the support plate (73).
9. A method of machining, characterized by, The machining device of claim 8 comprises the following main steps: Step one: workpiece clamping and system initialization Place the workpiece to be machined on the vacuum chuck (51) of the floating platform (5), so that the workpiece to be machined is fixed by the vacuum chuck (51); the central controller (8) calls the preset machining process parameters according to the input workpiece material and geometric feature information, controls the air pressure of the first low-friction air cylinder (61) and the second low-friction air cylinder (71) to drop to a first preset low pressure value, and simultaneously closes the excitation current of the first magnetorheological fluid damper (62) and the second magnetorheological fluid damper (72), so that the system is in a low stiffness / low damping mode, and the workpiece is naturally positioned without additional mechanical clamping stress; Step two: adaptive multi-stage machining process control Coarse machining stage: the three-way force sensor (52) monitors the stress state of the workpiece in real time, and when the stress in any direction is detected to exceed a first threshold value, the central controller (8) controls the air pressure of the first low-friction air cylinder (61) or the second low-friction air cylinder (71) in the corresponding direction and the associated direction to rise to a second preset high pressure value, simultaneously connects the first preset excitation current for the first magnetorheological fluid damper (62) or the second magnetorheological fluid damper (72), so that the system is switched to a high stiffness / high damping mode to effectively suppress cutting vibration; the first threshold value is the stress threshold value in the coarse machining state; Fine machining stage: after coarse machining is completed, the central controller (8) switches the system back to the low stiffness / low damping mode: the air pressure of the first low-friction air cylinder (61) or the second low-friction air cylinder (71) is reduced to a third preset low pressure value, and the excitation current of the first magnetorheological fluid damper (62) or the second magnetorheological fluid damper (72) is significantly reduced or closed, so as to actively release the residual stress accumulated by the workpiece in the coarse machining; Step three: machining completion and system reset After fine machining is completed, first, the vacuum system of the vacuum chuck (51) is closed, then the air pressure of the first low-friction air cylinder (61) and the second low-friction air cylinder (71) is released, and the excitation current of the first magnetorheological fluid damper (62) and the second magnetorheological fluid damper (72) is closed, under the action of the spherical hinge connecting mechanism, the floating platform (5) automatically returns to the initial position, the machined workpiece is removed, and the next clamping cycle is waited.