An adaptive positioning blade tool and blade positioning machining method

Abstract

The application discloses a self-adaptive positioning blade tool and a blade positioning machining method. The tool comprises a bed, a main clamping mechanism, a tail top mechanism, a guide rail and at least one set of ring support mechanisms. The ring support mechanisms are slidably arranged on the guide rail and located between the main clamping mechanism and the tail top mechanism to adjust the axial support position. The ring support mechanism comprises a ring sliding seat and a driven rotary ring. The driven rotary ring is formed by the joint of an upper ring body and a lower ring body and can rotate synchronously with the blade. The inner walls of the upper ring body and the lower ring body are oppositely provided with a plurality of top support devices. Each top support device can independently and closely abut the blade profile. The top support device comprises a floating top rod and a profiled pressure head. The profiled pressure head contains a profiled capsule filled with particles. When abutting the blade profile, the profiled pressure head deforms to fit the twisted curved surface. After vacuumizing, the particles are blocked to be solidified into a rigid support state. The application considers the profiled fitting capacity and the support rigidity, the support position is axially adjustable, and the technical problems of insufficient rigidity and cutting vibration in the middle section of the rotary machining of the long blade of the gas turbine are effectively solved.

Description

Technical Field

[0001] This invention belongs to the field of gas turbine blade machining tooling technology, specifically relating to an adaptive positioning blade tooling and a blade positioning machining method. Background Technology

[0002] Gas turbine blades are spatially twisted, thin-walled curved surface components. The blade profile changes continuously along the blade height, with a thin wall thickness and uneven rigidity distribution. During machining, the blade profile is typically milled using a rotary method, with the tenon end clamping and the blade tip providing support. For longer blades, the mid-section is far from the clamping points at both ends, resulting in significantly insufficient machining rigidity. Under cutting forces, this makes them prone to bending deformation and chatter, leading to out-of-tolerance profile accuracy and deteriorated surface quality. Therefore, auxiliary supports are required in the mid-section of the blade.

[0003] Existing blade auxiliary supports mainly fall into two categories: rigid supports and flexible supports. Rigid supports use support blocks or rigid contacts, making hard contact with the blade profile. This results in a small contact area, making them unsuitable for adapting to spatially tortuous profiles. Excessive local stress can easily leave indentations on thin-walled blades, and the support profile must be re-ground every time the blade type is changed, leading to low changeover efficiency. Flexible supports use elastic media or hydraulic floating structures, which can conform to the blade profile to some extent, but their rigidity is limited, making it difficult to withstand the large cutting forces during rough machining, and vibration is still prone to occur during processing.

[0004] This demonstrates an inherent contradiction in existing blade auxiliary supports: a difficulty in simultaneously achieving both conformal fitting capability and sufficient support rigidity. Rigid supports offer sufficient rigidity but poor fitting and are prone to surface damage, while flexible supports provide good fitting but lack rigidity and are susceptible to vibration. Furthermore, existing auxiliary supports are mostly fixed in position, unable to flexibly adjust their location according to changes in the machining section, and also ill-suited to the clamping requirements of blades of varying lengths. Therefore, there is an urgent need for an adaptive positioning blade fixture capable of simultaneously achieving conformal fitting and high-rigidity support, with an adjustable support position, to solve the auxiliary support challenges in the rotary machining of long gas turbine blades. Summary of the Invention

[0005] To address the problems and shortcomings of the existing technologies, this invention provides an adaptive positioning blade tooling and blade positioning machining method that balances conformal fitting capability and support rigidity. The support position is axially adjustable, effectively solving the technical problems of insufficient rigidity in the middle section of the rotary machining of long gas turbine blades, cutting vibration, out-of-tolerance profiles, and damage to thin-walled profiles.

[0006] This invention is achieved through the following technical solution: An adaptive positioning blade tooling includes a bed, a main clamping mechanism, a tail top mechanism, and a guide rail. The guide rail is fixed on the top of the bed, the main clamping mechanism is fixed at one end of the guide rail, and the tail top mechanism is slidably mounted on the guide rail. It also includes at least one set of ring support mechanisms located between the main clamping mechanism and the tail top mechanism and slidably mounted on the guide rail. The ring support mechanism includes a ring slide seat and a driven rotary ring. The ring slide seat slides with the guide rail to adjust the axial support position. The driven rotary ring rotates within the ring slide seat and can rotate synchronously with the blade. The driven rotary ring is formed by the upper ring body and the lower ring body. Several top supports are arranged opposite each other on the inner walls of the two ring bodies. Each top support can independently conform to the shape and tighten the blade profile. The support includes a floating push rod and a conformal pressure head located at the inner end of the floating push rod. The conformal pressure head can flexibly conform to the blade profile and then be rigidified to rigidly press the blade.

[0007] At least one set of ring support mechanisms sliding on the guide rail is added between the main clamping mechanism and the tail support mechanism. The ring support mechanism achieves free adjustment of the axial support position through the sliding engagement of the ring slide seat and the guide rail, so that the support point can be accurately positioned in the weakest middle section of the blade, rather than being limited to a fixed position. The driven rotary ring rotates and engages within the ring slide seat and can rotate synchronously with the blade, so that the support function is completely decoupled from the blade rotational motion. During the entire rotary milling process, the ring support mechanism continuously provides support without interfering with the cutting motion, which is impossible with fixed support. The driven rotary ring adopts an upper and lower ring body mating structure, which facilitates the loading and unloading of the blade and is convenient to open and close. Several top supports are arranged opposite each other on the inner walls of the upper and lower ring bodies. Each top support can independently conform to the shape and clamp the blade surface, forming a multi-point support system around the blade circumference, distributing the cutting force to multiple support points and avoiding local deformation of thin walls caused by concentrated force at a single point. The conformal indenter at the end of the support can first flexibly conform to the blade profile and then rigidify to press firmly. During the conforming stage, it fully adapts to the spatially twisted profile, eliminating the risk of hard contact indentation. During the rigidification stage, it provides high-rigidity support to resist cutting forces. This solution systematically solves the problem of insufficient rigidity in the mid-section of long blades from four dimensions: adjustable support position, rotational follow-up, multi-point support around the blade, and integrated conformal rigidification.

[0008] Furthermore, the conformal pressure head includes a connecting seat, a conformal bladder, a filter screen, and several particles. The connecting seat is fixed to the inner end of the floating top rod and has an air chamber inside. The conformal bladder is fixed to the side of the connecting seat facing the blade and forms a receiving cavity inside. The particles are filled in the receiving cavity. The filter screen is placed between the connecting seat and the conformal bladder to prevent the particles from entering the air chamber. The air chamber and the receiving cavity are connected by an air passage and are connected to an external air extraction port. The conformal capsule is made of elastic material and can deform to fit the blade profile and clamping angle deviation when it comes into contact with the blade surface. After vacuuming, it solidifies into a rigid support state due to particle blockage.

[0009] The connecting seat is fixed to the inner end of the floating push rod and has an air chamber. The conformal bladder is fixed to the side of the connecting seat facing the blade and forms a receiving cavity inside. Particles are filled into the receiving cavity. A filter screen is placed between the connecting seat and the conformal bladder to prevent particles from entering the air chamber. The air chamber and the receiving cavity are connected by an air passage and connected to an external air extraction port. This structural design makes the conformal pressure head form a complete particle blocking execution unit. The conformal bladder is made of elastic material and can deform according to the shape of the blade surface when it comes into contact with the blade surface. It can not only adapt to the spatial twisted contour of the blade surface, but also compensate for the clamping angle deviation and individual differences of the blade, ensuring that the contact surface is completely fitted rather than local line contact or point contact, fundamentally eliminating the problem of excessive local stress of rigid support damaging the thin-walled surface. During vacuuming, the air chamber is connected to the receiving cavity through the filter screen. The airflow draws the air out of the conformal bladder. The particles are squeezed and compacted under negative pressure. The friction between the particles increases sharply and a blocking effect occurs. The conformal bladder solidifies from a flexible state to a rigid support state. The filter ensures unobstructed airflow while preventing particles from being drawn into the air chamber, which could cause blockages or damage to the vacuum pump, thus guaranteeing long-term stable system operation. An external vacuum source is connected to the extraction port to power the curing process.

[0010] Furthermore, a reed vibrator is installed on the side of the filter screen facing the conformal capsule. When vacuuming, the airflow passes through the reed vibrator and excites the reed vibrator to generate high-frequency micro-vibration. The micro-vibration of the reed vibrator is transmitted to the particles in the conformal capsule, causing the particles to be continuously vibrated and arranged during the vacuuming process. After the vacuuming is completed, the reed vibrator stops vibrating, and the particles are uniformly blocked and solidified.

[0011] A reed vibrator is installed on the side of the filter screen facing the conformal capsule. During vacuuming, the airflow passes through the reed vibrator, exciting it to generate high-frequency micro-vibrations. These micro-vibrations are transmitted to the particles inside the conformal capsule, causing them to continuously compact and align during the vacuuming process. This design specifically addresses a key technical problem in the particle clogging process. In the initial stage of vacuuming, the particles are in a loose state. If direct pressure is applied to compact them, voids can easily form between the particles, resulting in residual gaps and uneven support stiffness and weak areas after solidification. The reed vibrator utilizes the airflow itself during vacuuming as an excitation source, generating high-frequency micro-vibrations without the need for an additional driving device. This allows the particles to continuously rearrange and compact under the action of vibration, resulting in a denser and more uniform particle filling, a more continuous and complete contact force chain network, and an overall improvement and more uniform distribution of support stiffness after solidification. After vacuuming is completed, the reed vibrator stops vibrating as the airflow stops, the particles are uniformly clogged and solidified, and the support state is stable. This solution achieves particle compaction with a minimalist structure, using the system's own airflow as a power source without increasing additional energy consumption or control complexity. At the same time, it significantly improves the quality and reliability of the solidified support and avoids the problem of uneven support stiffness caused by the granules being suspended.

[0012] Furthermore, the particles are metal beads, and the surface of the metal beads is coated with a wear-resistant coating. The metal beads have a uniform diameter and are evenly filled in the receiving cavity. The conformal capsule has a double-layer structure, including an inner membrane for airtight sealing and a wear-resistant layer covering the outer side of the inner membrane.

[0013] The particle material and conformal capsule structure were further specified. The particles are metal beads with a wear-resistant coating. The metal beads are of uniform diameter and uniformly fill the cavity. The metal beads possess high hardness and compressive strength, forming a high-strength rigid support after clogging and solidification, capable of withstanding the large cutting forces during rough machining without breakage or plastic deformation. The wear-resistant coating effectively reduces wear between metal beads and between the metal beads and the inner wall of the conformal capsule, extending the service life of the conformal indenter while maintaining stable surface frictional characteristics of the particles, ensuring consistent support stiffness with each solidification. Uniform filling with metal beads of uniform diameter makes particle packing characteristics predictable and repeatable, ensuring stable and controllable support stiffness after solidification, avoiding inconsistent clogging behavior caused by mixed particle sizes. The conformal capsule employs a double-layer structure, including an inner membrane for airtight sealing and a wear-resistant layer covering the outer side of the inner membrane. The inner membrane ensures the airtightness of the conformal capsule, ensuring effective establishment and maintenance of negative pressure during vacuuming, a prerequisite for particle clogging and solidification. The wear-resistant layer directly contacts the blade profile, bearing the friction and pressure between it and the profile, protecting the inner liner from wear and puncture. Simultaneously, the wear-resistant layer's own wear-resistant properties extend the replacement cycle of the conformal bladder. The dual-layer structure separates the airtightness and wear-resistant functions, each using optimal materials to balance sealing reliability and contact durability.

[0014] Furthermore, the air chamber is connected to the vacuum source via a vacuum proportional valve. The vacuum proportional valve continuously adjusts the vacuum level of the air chamber, so that the degree of blockage of particles in the conformal capsule changes gradually with the vacuum level, thereby achieving stepless control of the conformal capsule support stiffness. High vacuum level corresponds to high rigidity support to bear the large cutting force of rough machining, while low vacuum level corresponds to flexible buffer to adapt to the low stress requirements of fine machining.

[0015] The gas chamber is connected to a vacuum source via a vacuum proportional valve. This valve continuously adjusts the vacuum level within the gas chamber, allowing the degree of blockage of particles within the conformal indenter to gradually change synchronously with the vacuum level, thus achieving stepless control of the conformal indenter's support stiffness. This design enables the same conformal indenter to provide differentiated support stiffness at different machining stages, overcoming the limitations of traditional fixed and unadjustable support stiffness. Under high vacuum, the particles are highly compressed and dense, resulting in high contact force and friction between particles, and a sufficient blockage effect. The conformal indenter exhibits a high-rigidity support state, capable of withstanding the large cutting forces during roughing and effectively suppressing cutting chatter and bending deformation. Under low vacuum, the particle compression is less severe, and the conformal indenter retains a certain degree of elastic deformation capacity, exhibiting a flexible buffer state, suitable for the low-stress requirements of finishing, and avoiding surface scratches or stress concentration caused by minute displacements during finishing. The continuous adjustment characteristic of the vacuum proportional valve ensures smooth and stepless stiffness changes without abrupt shifts in gear selection, allowing for precise matching of optimal support stiffness based on cutting parameters, tool condition, blade material, and other factors. This solution enables a single tooling setup to simultaneously meet the conflicting requirements of high rigidity in roughing and low stress in finishing, eliminating the need to replace support components between roughing and finishing processes, thus significantly improving processing efficiency and process adaptability.

[0016] Furthermore, the top support also includes a cylinder and an elastic reset member. The cylinder is fixed to the upper or lower ring body, and the floating top rod passes through the cylinder and can move axially back and forth. A driving air chamber is formed between the cylinder and the tail of the floating top rod. Inflating the driving air chamber can push the floating top rod to extend. The elastic reset member is connected between the cylinder and the floating top rod to provide a retraction preload for the floating top rod.

[0017] This pneumatic drive structure allows each support to extend and retract independently. When extended, it pushes the conformal pressure head against the blade profile; when retracted, it disengages from the profile for easy blade loading and unloading. The pneumatic drive features fast response, stable output, and a compact structure, making it suitable for arrangement within the limited space of the driven rotating ring's inner wall. Independent drive of each support means that the clamping action of each support point can be controlled individually. The extension amount can be adjusted according to the differences in surface curvature and rigidity at different circumferential positions of the blade, ensuring that all conformal pressure heads reliably conform to the profile and preventing some supporters from being falsely clamped or over-clamped. The elastic reset component automatically pulls the floating push rod back to the retracted position after the drive chamber is depressurized, eliminating the need for an additional retraction drive, simplifying the structure and control logic. Simultaneously, the retraction preload ensures stable storage of the support in the non-working state, without interfering with blade loading and ring opening and closing. This solution provides a reliable structural implementation for conformal clamping action, and the independent drive characteristic lays the foundation for separate pressure adjustment of the upper and lower rings.

[0018] Furthermore, the driving air chambers of each support on the upper ring body and the driving air chambers of each support on the lower ring body are independently connected to different pressure regulating circuits to adjust the clamping force of the support on the upper and lower ring bodies respectively.

[0019] This design fully considers the differences in stress and rigidity between the upper and lower sides of the blade profile. Gas turbine blades are spatially tortuous thin-walled components, with the blade cross-section constantly changing along the blade height. The curvature, wall thickness, and rigidity distribution on both sides of the blade back and face are asymmetrical, and the components of the cutting force also differ at different circumferential locations. If all the upper and lower ring support devices use a uniform clamping force, the side with weaker rigidity may deform due to excessive clamping force, while the side with stronger rigidity may be unstable due to insufficient clamping force. By setting independent pressure regulating circuits for the upper and lower ring support devices, the optimal clamping pressure can be set according to the actual rigidity and stress conditions on the upper and lower sides of the blade profile, matching the support force on both sides with the rigidity and cutting load of the corresponding areas, achieving a balanced and reasonable distribution of support force. The design of interconnected drive air chambers for the upper and lower ring supports allows the support members on the same ring to automatically maintain pressure balance. When the profile is uneven, the difference in the extension and retraction of the floating top rods provides adaptive compensation, eliminating the need for individual pressure adjustment. This simplifies control while ensuring reliable fit, significantly improving the stress rationality of the ring support and avoiding processing deformation caused by over- or under-support on one side.

[0020] Furthermore, the blade tooling also includes a first adjusting screw and a second adjusting screw. The first adjusting screw is driven by the sliding seat of the tail top mechanism, and the second adjusting screw is driven by the ring slide. The two adjusting screws are driven independently and each has a locking function, so that the tail top mechanism and the ring support mechanism can be moved independently along the guide rail and positioned at the target axial position, thereby adapting to the changes in different blade lengths and support sections.

[0021] A first and second adjusting screw are added. The first adjusting screw is connected to the sliding seat of the tail-end mechanism, and the second adjusting screw is connected to the ring slide. Both adjusting screws are driven independently and each has a locking function. This design allows the tail-end mechanism and the ring support mechanism to move and position along the guide rail completely independently and controllably. The first adjusting screw drives the tail-end mechanism axially, adapting to the clamping requirements of blades of different lengths. When the blade length changes, only the position of the tail-end mechanism needs to be adjusted, without changing the tooling or adding shims. The second adjusting screw drives the ring support mechanism axially, allowing the support point to be precisely positioned at the axial position corresponding to the section to be processed. This provides precise support for the weakest area of ​​rigidity in the middle section of the blade, and the support position can also be gradually adjusted according to the progress of the processing steps to follow the cutting section. The independent drive of the two screws means that the position adjustments of the tail-end mechanism and the ring support mechanism do not interfere with each other. They can be set precisely separately, and each locks after adjustment, ensuring stable positioning and preventing movement during processing. Lead screw drives are characterized by high positioning accuracy, strong load-bearing capacity, and good self-locking properties, and can withstand axial forces during the cutting process without displacement. This solution achieves independent and precise adjustment of the support position and tail tip position at the mechanical structure level, giving the tooling a wide range of blade length and section adaptability, overcoming the inherent defect of fixed support positions that cannot be adjusted.

[0022] An adaptive blade positioning machining method includes the following steps: S1. Clamping and positioning: Clamp the tenon end of the blade to the main clamping mechanism, and clamp the tip of the blade to the tail clamping mechanism to complete the initial positioning of the blade in the axial and circumferential directions. S2. Ring support in place: Move the ring support mechanism to the axial position corresponding to the section of the blade to be processed and lock it. Align the upper and lower ring bodies of the driven rotary ring so that each support is arranged around the blade profile. S3. Conformal clamping: Inflate the drive air chamber of each support to push the floating push rod out. The conformal bladder of the conformal pressure head abuts the blade profile and deforms to conform to the profile. S4. Solidification support: Vacuuming the conformal capsule causes the particles inside the conformal capsule to block the particles, and the conformal capsule is solidified from a flexible state to a rigid support state to rigidly press the blade. S5. Rotary machining: The main clamping mechanism drives the blade to rotate, and the driven rotary ring rotates synchronously with the blade. The tool performs cutting machining on the blade surface. S6. Demolding and unloading: After processing, release the air from the drive chambers of each support, retract the floating push rod, inflate the conformal capsule to restore the fluidity of the particles, restore the flexibility of the conformal capsule, separate the upper ring body and lower ring body and remove the blade.

[0023] This solution provides an adaptive blade positioning and machining method using the aforementioned tooling, comprising six steps: clamping and positioning, ring support placement, conformal clamping, curing and support, rotary machining, and demolding and unloading. This method separates conformal bonding and rigid curing into two independent stages. First, conformal clamping ensures the conformal capsule fully conforms to the blade profile. Then, vacuum curing transforms the flexible bonding state into a rigid support state. This two-step approach ensures both bonding quality and support rigidity. The clamping and positioning step completes the initial axial and circumferential positioning of the blade, providing a reference for subsequent ring support and clamping. The ring support placement step moves the ring support mechanism to the target axial position and aligns it with the driven rotary ring, allowing the support to be positioned around the blade profile. The conformal clamping step inflates the floating push rod, causing the conformal capsule to abut against the profile and deform accordingly. During this stage, the conformal capsule is in a flexible state, fully adapting to the tortuous profile without generating localized high pressure. The curing and support step involves vacuuming to cause a clogging effect, solidifying the conformal capsule into a rigid support. This stage significantly increases the support rigidity to resist cutting forces. In the rotary machining step, the driven rotary ring rotates synchronously with the blade, ensuring continuous and effective support. The demolding and unloading step is the reverse operation: venting and retracting the ejector rod, inflating to restore particle flowability, separating the ring body and unloading the blade, completing the process loop. This method has a clear operational logic and well-defined functions for each step, directly guiding on-site machining operations. Furthermore, the entire process requires no re-grinding of the support surface, resulting in high changeover efficiency.

[0024] Furthermore, in step S4, the vacuum degree of the conformal capsule is continuously adjusted via a vacuum proportional valve to steplessly control the support stiffness. In the roughing stage, the vacuum level is adjusted to a high degree to enhance the rigidity of the conformal capsule and bear the large cutting force. In the finishing stage, the vacuum level is adjusted to a low degree to give the conformal capsule elastic buffering to reduce machining stress.

[0025] In the solidification support step, the vacuum level of the conformal bladder is further continuously adjusted via a vacuum proportional valve to steplessly control the support stiffness, and the vacuum level is set differently according to the roughing and finishing stages. In the roughing stage, a high vacuum level is set to enhance the rigidity of the conformal bladder to withstand large cutting forces, while in the finishing stage, a low vacuum level is set to allow the conformal bladder to have elastic buffering to reduce machining stress. This method allows the support stiffness to be dynamically adjusted with each machining step, completing both roughing and finishing under the same clamping without replacing the support or resetting it. In the roughing stage, the cutting depth, feed rate, and cutting force are large. Under high vacuum, the particles are highly dense and clogged, and the conformal bladder exhibits near-rigid support, effectively suppressing bending deformation and chatter of the blade under large cutting forces, ensuring material removal efficiency and basic surface accuracy in roughing. In the finishing stage, the cutting force is small, but the requirements for surface quality and dimensional accuracy are extremely high. Under low vacuum, the conformal bladder retains moderate elasticity, absorbing minor vibrations during the cutting process and acting as an elastic buffer, avoiding surface quality deterioration caused by hard contact stress between the rigid support and the thin-walled blade, while also reducing residual machining stress. Continuous adjustment of the vacuum proportional valve ensures a smooth transition in stiffness switching, preventing instantaneous blade displacement due to sudden stiffness changes. This method links support stiffness control with machining process parameters, achieving synergistic optimization of process and tooling, and is a key support for integrated roughing and finishing machining.

[0026] The beneficial effects of this invention are: Firstly, it resolves the inherent contradiction between conformal fitting and rigid support. Existing rigid supports are prone to damaging the surface due to hard contact and cannot adapt to tortuous surfaces, while flexible supports offer good fit but lack sufficient rigidity to withstand the large cutting forces of rough machining. This invention employs the particle blocking principle. During the contact stage, the conformal indenter uses a flexible conformal capsule to completely fit the spatially tortuous thin-walled surface, eliminating local stress concentration and avoiding indentations. During the curing stage, vacuuming causes the particles to block and transform into a rigid entity, providing high-rigidity support sufficient to withstand the cutting forces of rough machining. The same component performs both flexible fitting and rigid support functions at different stages, fundamentally addressing two mutually restrictive performance requirements.

[0027] Secondly, it achieves axial adjustability and multi-segment adaptation of the support position. The ring support mechanism slides along the guide rail and locks independently, allowing for flexible positioning of the support point according to the blade length and the section to be processed. This ensures that the support always acts on the middle section of the blade where the cutting force is greatest and rigidity is weakest, overcoming the defect of fixed-position support that cannot be adjusted according to changes in the processing section. For ultra-long blades, multiple sets of ring support mechanisms can be arranged to form multi-point support, further improving the overall processing rigidity.

[0028] Third, the driven rotary ring rotates synchronously with the blade, decoupling the support from the rotary motion. The ring support mechanism does not interfere with the rotary machining motion of the blade, and the top support rotates together with the driven rotary ring, continuously providing stable support throughout the entire rotary cutting process, eliminating the friction and interference problems between the traditional fixed support and the rotating workpiece.

[0029] Fourth, the support stiffness can be steplessly adjusted. By continuously adjusting the vacuum level inside the conformal bladder through a vacuum proportional valve, the degree of particle blockage changes synchronously and gradually. This provides high rigidity support to bear large cutting forces during the roughing stage, and reduces stiffness to achieve elastic buffering and reduce machining stress during the finishing stage. One set of tooling covers the entire roughing and finishing process without the need to replace the support components.

[0030] Fifth, high changeover efficiency. The conformal indenter automatically adapts to the profile and clamping angle deviation of different blade models, eliminating the need for grinding the support profile for each model as required by rigid supports. This significantly shortens changeover preparation time and reduces tooling manufacturing costs. Attached Figure Description

[0031] Figure 1 A connection diagram illustrating one embodiment of an adaptive positioning blade tooling in this invention; Figure 2 A schematic diagram illustrating one embodiment of an adaptive positioning blade tooling in this invention; Figure 3 Used to explain Figure 2 Enlarged view of a portion of point A in the middle; Figure 4 A front view illustrating an illustrative embodiment of an adaptive positioning blade tooling according to the present invention; Figure 5 A side sectional view illustrating a schematic embodiment of an adaptive positioning blade tooling according to the present invention; Figure 6 Used to explain Figure 5 A magnified view of a portion of point B in the middle.

[0032] List of components and reference numerals: 1. Bed; 2. Main clamping mechanism; 3. Tailstock mechanism; 4. Guide rail; 5. Ring support mechanism; 51. Ring slide seat; 52. Driven rotary ring; 521. Upper ring body; 522. Lower ring body; 53. Top support; 531. Floating top rod; 532. Conformal pressure head; 5321. Connecting seat; 5322. Conformal bladder; 5323. Filter screen; 5324. Particle; 5325. Air chamber; 5326. Receiving cavity; 5327. Air extraction port; 5328. Spring vibrator; 533. Cylinder; 534. Elastic reset component; 6. First adjusting screw; 7. Second adjusting screw; 8. Blade. Detailed Implementation

[0033] The following detailed embodiments fully disclose the technical solution of the present invention, ensuring that those skilled in the art can reproduce the invention and achieve its technical effects without creative effort. These embodiments are merely exemplary forms embodying the core concept of the present invention and should not be used as a basis for limiting the scope of the claims; all equivalent solutions derived from the technical principles of the present invention through conventional means fall within the protection scope of the present invention.

[0034] like Figures 1 to 6 The diagram illustrates an adaptive positioning blade fixture, integrally arranged on a bed 1. A guide rail 4 is fixed to the top of the bed 1, extending axially along the blade 8. A main clamping mechanism 2 is fixed to one end of the guide rail 4, used to clamp the tenon end of the blade 8 and drive the blade 8 to rotate. A tail-end mechanism 3 slides on the guide rail 4, used to press against the tip of the blade 8; its axial position can be adjusted along the guide rail 4 to accommodate different blade lengths. At least one set of ring support mechanisms 5 is arranged between the main clamping mechanism 2 and the tail-end mechanism 3, also sliding on the guide rail 4, used to provide circumferential auxiliary support in the middle section of the blade.

[0035] The ring support mechanism 5 includes a ring slide seat 51 and a driven rotary ring 52. The ring slide seat 51 is slidably engaged with the guide rail 4 and can move axially along the guide rail 4 to adjust the support position. After moving into position, it is locked and fixed. The driven rotary ring 52 is rotatably engaged within the ring slide seat 51 through a rotary support member. Its rotation axis coincides with the axis of the blade 8, and it can rotate synchronously with the blade 8 through the friction between the top support 53 and the blade 8 when the blade 8 rotates. The driven rotary ring 52 is formed by the engagement of an upper ring body 521 and a lower ring body 522. Several top supports 53 are arranged opposite each other on the inner walls of the upper ring body 521 and the lower ring body 522. Each top support 53 is distributed along the inner wall of the upper ring body 521 or the lower ring body 522, and after engagement, it forms a support and fixation around both sides of the blade 8.

[0036] The support device 53 includes a cylinder 533, a floating push rod 531, an elastic reset member 534, and a conformal pressure head 532. The cylinder 533 is fixed to a mounting seat on the inner wall of the upper ring 521 or the lower ring 522. The floating push rod 531 passes through the cylinder 533 and can reciprocate along the axial direction of the cylinder 533. An air chamber 5325 is formed between the cylinder 533 and the tail of the floating push rod 531. When air is filled into the air chamber 5325, the air pressure pushes the floating push rod 531 to extend towards the blade 8. The elastic reset member 534 is connected between the cylinder 533 and the floating push rod 531. After the air chamber 5325 is deflated, it provides a retraction preload force to the floating push rod 531, causing it to automatically return to its initial position. The conformal pressure head 532 is installed at the end of the floating push rod 531 facing the blade 8.

[0037] The conformal pressure head 532 includes a connecting seat 5321, a conformal capsule 5322, a filter screen 5323, and a number of particles 5324. The connecting seat 5321 is fixed to the inner end of the floating top rod 531, and an air chamber 5325 is formed inside the connecting seat 5321. The air chamber 5325 is externally connected to an air extraction port 5327 via a pipeline. The conformal capsule 5322 is fixed to the side of the connecting seat 5321 facing the blade 8, and a receiving cavity 5326 is formed inside the conformal capsule 5322, which is filled with particles 5324. The filter screen 5323 is located between the connecting seat 5321 and the conformal capsule 5322. The mesh size of the filter screen 5323 is smaller than the diameter of the particles 5324, allowing airflow while preventing particles 5324 from entering the air chamber 5325. The air chamber 5325 and the receiving cavity 5326 are connected through the air passage of the filter screen 5323. The conformal capsule 5322 is made of elastic material, which has good elastic deformation ability and airtightness. A reed oscillator 5328 is installed on the side of the filter 5323 facing the conformal capsule 5322. The reed oscillator 5328 is an elastic metal sheet with one end fixed and the other end free. When the airflow passes through, it excites the free end to vibrate.

[0038] The particles 5324 are made of metal beads with a wear-resistant coating on their surface. All metal beads are of the same diameter and are uniformly filled in the receiving cavity 5326 of the conformal capsule 5322. The conformal capsule 5322 has a double-layer structure, with an inner layer being an airtight inner membrane and an outer layer being a wear-resistant layer covering the outside of the inner membrane. The wear-resistant layer is in direct contact with the blade's 8-shaped surface.

[0039] The air chamber 5325 of the conformal pressure head 532 is connected to a vacuum source via a vacuum proportional valve, which can continuously adjust the vacuum level of the air chamber 5325. The air chambers 5325 of each support 53 on the upper ring 521 are interconnected and connected to a pressure regulating circuit, and the air chambers 5325 of each support 53 on the lower ring 522 are interconnected and connected to another pressure regulating circuit. The two pressure regulating circuits are set independently and can adjust the clamping force of the support 53 on the upper and lower rings 522 respectively.

[0040] The sliding seat of the tail top mechanism 3 is connected to the first adjusting screw 6, and the ring sliding seat 51 of the ring support mechanism 5 is connected to the second adjusting screw 7. The two adjusting screws are driven independently and are each equipped with a driving mechanism and a locking mechanism, so that the tail top mechanism 3 and the ring support mechanism 5 can be independently moved along the guide rail 4 and positioned at the target axial position.

[0041] The working process of this tooling is the adaptive blade positioning machining method, which includes the following steps.

[0042] S1. Clamping and Positioning. The tenon end of the blade 8 is inserted into the main clamping mechanism 2 and clamped and fixed. The blade tip is clamped and held by the tail-top mechanism 3, completing the initial positioning of the blade 8 in the axial and circumferential directions. In this step, the axial position of the tail-top mechanism 3 can be adjusted by the first adjusting screw 6 to adapt to the current length of the blade 8.

[0043] S2. Ring support in place. The ring support mechanism 5 is driven to move along the guide rail 4 by the second adjusting screw 7, and positioned and locked to the axial position corresponding to the section of blade 8 to be processed. After the blade 8 is placed at the center of the driven rotary ring 52, each top support 53 is arranged around both sides of the blade 8 profile. Air pressure is applied to the top supports 53, so that the top supports 53 are pressed against the blade 8 under constant pressure, thereby locking the blade 8.

[0044] S3. Conformal Tightening. The air chambers 5325 of the upper ring 521 and lower ring 522 are inflated. The air pressure pushes the floating push rods 531 to extend towards the blade 8, and the conformal bladder 5322 of the conformal pressure head 532 abuts against the blade 8 profile. At this time, the conformal bladder 5322 is in a flexible state without vacuum, and the internal particles 5324 are fluid. Under the thrust of the floating push rods 531, the conformal bladder 5322 elastically deforms along the profile of the blade 8, completely conforming to the spatially twisted profile, while compensating for clamping angle deviations. The pressure regulating circuits of the upper ring 521 and lower ring 522 can be set with different inflation pressures to match the tightening force on both sides with the rigidity of the profile.

[0045] S4. Solidification Support. A vacuum is drawn into the conformal capsule 5322 through the evacuation port 5327. Air is extracted through the filter 5323 and air chamber 5325, increasing the negative pressure inside the conformal capsule 5322. During the vacuuming process, the airflow passes through the reed oscillator 5328, exciting it to generate high-frequency micro-vibrations. These micro-vibrations are transmitted to the particles 5324, causing them to continuously vibrate and align. As the vacuum level increases, the particles 5324 are compressed and compacted, leading to a sharp increase in friction between them and a blockage effect. The conformal capsule 5322 gradually solidifies from a flexible state to a rigid support state. The vacuum level can be continuously adjusted according to the processing stage using a vacuum proportional valve. A high vacuum level is used in the roughing stage to obtain high-rigidity support, while a low vacuum level is used in the finishing stage to obtain elastic buffering. It should be noted that when evacuating the conformal capsule 5322, the floating push rod 531 will extend to a certain extent to maintain a constant compressive force on the blade 8.

[0046] S5. Rotary machining. The main clamping mechanism 2 drives the blade 8 to rotate around its own axis. The driven rotating ring 52 rotates synchronously with the blade 8 under the action of friction between the top support 53 and the blade 8, while the ring slide 51 remains fixed. The cutting tool performs milling machining on the blade 8 profile. The ring support mechanism 5 continuously provides a surrounding rigid support in the middle section of the blade body to suppress bending deformation and chatter caused by cutting force.

[0047] S6. Demolding and Unloading. After processing, release the air from the air chambers 5325 of each support 53. The floating push rod 531 retracts under the action of the elastic reset member 534, and the conformal pressure head 532 disengages from the blade 8 surface. Inflate the conformal bladder 5322 to break the vacuum, the particles 5324 regain fluidity, and the conformal bladder 5322 returns to its flexible state. Open the upper ring body 521 and the lower ring body 522, and remove the blade 8.

[0048] The physical mechanism of the blockage effect of particles 5324 requires further explanation. When the conformal capsule 5322 is not evacuated, the metal beads filling it are in a loosely packed state. The contact force between particles 5324 is small, and the particles 5324 can move relatively, exhibiting fluid-like fluidity. Therefore, the conformal capsule 5322 can freely deform under external force to conform to the molded surface. When the conformal capsule 5322 is evacuated, the external atmospheric pressure exerts an isotropic compressive force on the internal particles 5324 through the capsule wall, compressing the particles 5324 into a denser state. As the degree of compression increases, the contact area between particles 5324 increases, the normal contact force increases, and the frictional force between particles 5324 increases proportionally to the normal force. When the packing density of particles 5324 reaches a critical value, an overlapping contact force chain network forms between the particles 5324. This force chain transmits the load from one contact point to another, transferring the externally distributed load to the entire support structure through the particle 5324 framework. At this point, the particle 5324 system loses its fluidity and exhibits the mechanical properties of a solid, i.e., a blockage effect occurs. The higher the vacuum level and the greater the extrusion pressure, the denser the particle 5324 packing, the stronger and more continuous the contact force chain network, and the higher the equivalent stiffness and strength of the system. When the conformal capsule 5322 is inflated to restore normal pressure, the extrusion pressure is released, the contact force between particles 5324 decreases, the force chain network disintegrates, the particles 5324 regain their fluidity, and the conformal capsule 5322 regains its flexibility. The high-frequency micro-vibration of the reed oscillator 5328 during the vacuuming process causes the particles 5324 to continuously rearrange while being compressed and densified, eliminating the voids between particles 5324, making the packing more uniform and dense, and the force chain network more continuous and complete, thereby improving the uniformity and overall level of the support stiffness after curing.

[0049] The following explains the extended alternatives to the key technical solutions.

[0050] The material and structure of the particles 5324 in the conformal pressure head 532 can be replaced. Besides metal beads, the particles 5324 can also be ceramic beads, glass beads, or high-polymer hard particles 5324. Ceramic beads have high hardness and wear resistance, glass beads are low-cost and have a smooth surface, and high-polymer particles 5324 have low density and are gentler on the profile. The choice can be made according to the support stiffness requirements and the material properties of the blade 8. Besides spherical shapes, the particles 5324 can also be short cylindrical or irregularly shaped. Non-spherical particles 5324 have stronger interlocking and higher stiffness after clogging, but their flowability is correspondingly reduced. In addition to a double-layer structure, the conformal capsule 5322 can also be a single-layer homogeneous elastic capsule, integrating airtightness and wear resistance into the same material. This results in a simpler structure but a relatively shorter lifespan. Alternatively, a multi-layer composite structure can be used, with a reinforcing fiber layer added between the wear-resistant layer and the inner membrane to improve the capsule's pressure resistance. In addition to fixed connection, the connection between the conformal capsule 5322 and the connecting seat 5321 can also be a detachable threaded connection or a clamp connection, which makes it easy to replace the conformal capsule 5322 separately after it is worn.

[0051] The driving method of the top support 53 can be replaced. In addition to pneumatic drive, hydraulic drive can also be used, replacing the air chamber 5325 with a driving oil chamber and connecting it to the hydraulic circuit. Hydraulic drive has greater output and higher rigidity, suitable for ultra-large blades 8 or heavy cutting conditions. Alternatively, electric screw drive can be used, with a micro motor driving the screw nut pair to push the floating top rod 531 to extend and retract. Electric drive has high control precision, can accurately control the extension amount and clamping force, and does not require an air or oil source, but the structural size is larger. In addition to spring, the elastic reset member 534 can also use pneumatic reset or hydraulic reset. A reset chamber is set at the end of the floating top rod 531, and low-pressure fluid is introduced to achieve retraction, resulting in a more stable reset force.

[0052] The number and axial arrangement of the ring support mechanism 5 can be substituted. In addition to a single ring support mechanism 5, two or more ring support mechanisms 5 can be arranged for blades 8 with a larger length. Each ring support mechanism 5 slides and is positioned independently along the guide rail 4, supporting different axial sections of the blade body to form a multi-point support system and further improve the overall rigidity.

[0053] The engagement method of the driven rotary ring 52 can be replaced. Besides the top-bottom engagement structure, a left-right engagement structure can also be used, dividing the driven rotary ring 52 into a left half-ring and a right half-ring, which engage and clamp from both sides of the blade 8; alternatively, an open ring structure can be used, with an axial opening in the ring body. A radial contraction mechanism reduces the opening to achieve clamping, and expands the opening to achieve loosening, without completely disassembling the ring body. The rotary bearing between the driven rotary ring 52 and the ring slide 51 can be a sliding bushing or an air bearing, in addition to a rolling bearing. Air bearings have extremely low frictional resistance, resulting in smoother rotation.

[0054] Vacuum control circuits can be used as alternatives. Besides continuous adjustment with a vacuum proportional valve, a combination of a switching valve and a gas storage tank can be used to achieve leveled adjustment. Several fixed vacuum levels are provided by preset pressures in different gas storage tanks. This method is simple and low-cost, but stepless control is not possible. The vacuum circuits of each conformal pressure head 532 can be centrally controlled (i.e., all conformal bladders 5322 are evacuated uniformly) or independently controlled (i.e., each conformal bladder 5322 has its own vacuum valve). Independent control allows for differentiated setting of support stiffness for different circumferential positions, but the control system is more complex. In addition to a centralized vacuum pump, a vacuum generator can also be used as the vacuum source, utilizing compressed air to generate negative pressure, suitable for workshop environments with existing gas sources.

[0055] In summary, the above embodiments are intended to fully present the implementable forms and technical logic of the present invention, and do not constitute a limitation on the scope of protection of the present invention. All equivalent substitutions, structural adjustments, and feature combinations made based on the technical essence of the present invention, without departing from the core inventive concept, should fall within the scope of protection defined by the claims of the present invention.

Claims

1. An adaptive positioning blade fixture, comprising a bed (1), a main clamping mechanism (2), a tail-end mechanism (3), and a guide rail (4), wherein the guide rail (4) is fixedly mounted on the top of the bed (1), the main clamping mechanism (2) is fixedly mounted on one end of the guide rail (4), and the tail-end mechanism (3) is slidably mounted on the guide rail (4), characterized in that, It also includes at least one set of ring support mechanisms (5) located between the main clamping mechanism (2) and the tail top mechanism (3) and slidably mounted on the guide rail (4). The ring support mechanism (5) includes a ring slide seat (51) and a driven rotary ring (52). The ring slide seat (51) is slidably engaged with the guide rail (4) to adjust the axial support position. The driven rotary ring (52) is rotatably engaged in the ring slide seat (51) and can rotate synchronously with the blade (8). The driven rotary ring (52) is formed by the upper ring body (521) and the lower ring body (522) being joined together. Several top supports (53) are arranged opposite each other on the inner walls of the two. Each top support (53) can independently conform to the shape and press against the blade (8) profile. The top support (53) includes a floating top rod (531) and a conformal pressure head (532) located at the inner end of the floating top rod (531). The conformal pressure head (532) can flexibly conform to the blade (8) profile and then be rigidly pressed against the blade (8).

2. The adaptive positioning blade tooling according to claim 1, characterized in that, The conformal pressure head (532) includes a connecting seat (5321), a conformal bladder (5322), a filter screen (5323), and a number of particles (5324). The connecting seat (5321) is fixed to the inner end of the floating top rod (531). An air chamber (5325) is opened in the connecting seat (5321). The conformal bladder (5322) is fixed to the side of the connecting seat (5321) facing the blade (8) and forms a receiving cavity (5326) inside. The particles (5324) are filled in the receiving cavity (5326). The filter screen (5323) is disposed between the connecting seat (5321) and the conformal bladder (5322) to prevent the particles (5324) from entering the air chamber (5325). The air chamber (5325) is connected to the receiving cavity (5326) by an air passage and is externally connected to an air extraction port (5327). The conformal capsule (5322) is made of elastic material and can conform to the shape of the blade (8) when it comes into contact with the blade (8) profile to adapt to the deviation of the blade (8) profile and clamping angle. After vacuuming, it solidifies into a rigid support state due to the blockage of the particles (5324).

3. The adaptive positioning blade fixture according to claim 2, characterized in that, A reed vibrator (5328) is installed on the side of the filter screen (5323) facing the conformal capsule (5322). When vacuuming, the airflow passes through the reed vibrator (5328) and excites the reed vibrator (5328) to generate high-frequency micro-vibration. The micro-vibration of the reed vibrator (5328) is transmitted to the particles (5324) in the conformal capsule (5322), causing the particles (5324) to be continuously vibrated and arranged during the vacuuming process. After the vacuuming is completed, the reed vibrator (5328) stops vibrating, and the particles (5324) are uniformly blocked and solidified.

4. The adaptive positioning blade fixture according to claim 2, characterized in that, The particles (5324) are metal beads, and the surface of the metal beads is coated with a wear-resistant coating. The metal beads have the same diameter and are uniformly filled in the receiving cavity (5326). The conformal capsule (5322) has a double-layer structure, including an inner membrane for airtight sealing and a wear-resistant layer covering the outer side of the inner membrane.

5. The adaptive positioning blade fixture according to claim 2, characterized in that, The air chamber (5325) is connected to a vacuum source via a vacuum proportional valve. The vacuum proportional valve continuously adjusts the vacuum level of the air chamber (5325), so that the degree of blockage of particles (5324) in the conformal capsule (5322) gradually changes synchronously with the vacuum level, thereby achieving stepless control of the support stiffness of the conformal capsule (5322). High vacuum level corresponds to high rigidity support to bear the large cutting force of rough machining, while low vacuum level corresponds to flexible buffer to adapt to the low stress requirements of fine machining.

6. The adaptive positioning blade fixture according to claim 1, characterized in that, The top support (53) also includes a cylinder (533) and an elastic reset member (534). The cylinder (533) is fixed to the upper ring (521) or the lower ring (522). The floating top rod (531) passes through the cylinder (533) and can move axially back and forth. An air chamber (5325) is formed between the cylinder (533) and the tail of the floating top rod (531). Inflating the air chamber (5325) can push the floating top rod (531) to extend. The elastic reset member (534) is connected between the cylinder (533) and the floating top rod (531) to provide a retraction preload force for the floating top rod (531).

7. The adaptive positioning blade fixture according to claim 6, characterized in that, The air chambers (5325) of each support device (53) on the upper ring (521) and the air chambers (5325) of each support device (53) on the lower ring (522) are independently connected to different pressure regulating circuits to adjust the clamping force of the support devices (53) on the upper ring (521) and the lower ring (522) respectively.

8. The adaptive positioning blade tooling according to claim 1, characterized in that, It also includes a first adjusting screw (6) and a second adjusting screw (7). The first adjusting screw (6) is connected to the sliding seat of the tail top mechanism (3) and the second adjusting screw (7) is connected to the ring slide (51). The two adjusting screws are driven independently and each has a locking function, so that the tail top mechanism (3) and the ring support mechanism (5) can be independently moved along the guide rail (4) and positioned at the target axial position, thereby adapting to the changes in different blade lengths and support sections.

9. An adaptive blade positioning machining method, employing the adaptive positioning blade tooling as described in any one of claims 1-8, characterized in that, Includes the following steps: S1. Clamping and positioning: clamp the tenon end of the blade (8) to the main clamping mechanism (2), and clamp the tip of the blade to the tail top mechanism (3) to complete the initial positioning of the blade (8) in the axial and circumferential directions. S2. The ring support is in place. The ring support mechanism (5) is moved to the axial position corresponding to the section to be processed of the blade (8) and locked. The upper ring body (521) and lower ring body (522) of the driven rotary ring (52) are aligned so that each top support (53) is arranged around the blade (8) profile. S3, conformal clamping, inflate the air chamber (5325) of each top support (53) to push the floating top rod (531) out, the conformal bladder (5322) of the conformal pressure head (532) abuts against the blade (8) profile and conforms to the profile to fit the profile. S4. Solidify the support, evacuate the conformal capsule (5322) to cause the particles (5324) inside the conformal capsule (5322) to block the flow, and solidify the conformal capsule (5322) from a flexible state to a rigid support state to rigidly press the blade (8). S5. Rotary machining: The main clamping mechanism (2) drives the blade (8) to rotate, and the driven rotary ring (52) rotates synchronously with the blade (8). The tool performs cutting machining on the blade (8) profile. S6. Demolding and unloading: After processing, release the air from the air chambers (5325) of each top support (53), retract the floating top rod (531), inflate the conformal capsule (5322) to restore the fluidity of the particles (5324), restore the flexibility of the conformal capsule (5322), separate the upper ring body (521) and the lower ring body (522) and remove the blade (8).

10. The adaptive blade positioning machining method according to claim 9, characterized in that, In step S4, the vacuum degree of the conformal capsule (5322) is continuously adjusted via a vacuum proportional valve to steplessly control the support stiffness. In the roughing stage, the vacuum level is adjusted to a high degree to enhance the rigidity of the conformal capsule (5322) to withstand large cutting forces. In the finishing stage, the vacuum level is adjusted to a low degree to provide elastic buffering for the conformal capsule (5322) to reduce machining stress.

Images