Micro-vibration adaptive drilling and burr suppression processing method and system

Abstract

The application discloses a kind of microvibration self-adaptive drilling burr processing method and system, and the annular plastic slip interface of parallel bottom surface is prefabricated in workpiece to be penetrated region by shallow, middle layer hierarchical steady-state axial microvibration extrusion, and workpiece matrix is separated from burr matrix in advance;Drill advances to the locking feed when penetrating critical position, and impact microvibration is switched to generate circumferential penetration microcrack in slip interface, and metal is cut along crack interface after burr connection is pre-disconnected, and continuous flanging at hole is eliminated from material deformation source.The scheme only switches steady-state, impact, intermittent microvibration according to pre-recorded workpiece thickness calibration stroke, without cutting force, visual multi-sensing closed loop;Rigid limit clamping, coaxial multi-mode microvibration excitation and stroke matching control module are set in matching system.Discard the passive burr suppression idea of existing vibration reduction, and the process timing and metal separation mechanism are completely new, and once clamping is completed Processing finishing, offline deburring process is saved, and processing precision, efficiency and equipment stability are improved.

Description

Technical Field

[0001] This invention belongs to the field of metal cutting processing technology, and in particular relates to a micro-vibration adaptive drilling burr suppression processing method and system. Background Technology

[0002] During mechanical drilling, when the drill bit penetrates the workpiece, the metal at the exit position undergoes plastic stretching under the axial cutting thrust, forming continuous flanged burrs. Current vibration-assisted drilling generally employs full-range vibration cutting, but its core idea is to passively reduce burr size by only lowering the average cutting force through vibration. This approach cannot completely eliminate burrs and suffers from two major technical flaws:

[0003] 1. Without pre-layering the metal in the workpiece's penetration area, the bottom metal is stretched synchronously at the moment of drilling through, inevitably forming continuous burrs;

[0004] 2. The existing processing sequence is to continuously feed and drill through the workpiece in one go, without a pre-cracking process before penetration. The metal is directly pulled apart to produce a flanged edge. There is no process logic of first pre-forming the separation surface, then pre-cracking, and finally cutting along the interface. Summary of the Invention

[0005] The purpose of this invention is to provide a micro-vibration adaptive drilling burr suppression method and system to solve the problems mentioned in the background art.

[0006] In view of this, the present invention provides a micro-vibration adaptive drilling method for burr suppression, comprising:

[0007] The workpiece is rigidly clamped and the workpiece thickness reference data is entered.

[0008] The drill bit is driven to complete the tool setting and positioning, and the critical stroke point for penetration is calibrated based on the workpiece thickness reference.

[0009] Control the shallow feed of the drill bit to cut and shape, and simultaneously output steady-state axial micro-vibration to compress and generate an initial plastic slip base inside the workpiece;

[0010] Control the continuous feed cutting of the middle layer of the drill bit, maintain steady axial micro-vibration to continuously squeeze the metal below the slip base, extend and strengthen the slip base downward, form a complete annular plastic slip interface in the area to be penetrated in the workpiece, and use the plastic slip interface to pre-separate the workpiece matrix and the thin metal layer below to be formed with burrs.

[0011] The drill bit's axial feed stroke is read in real time. When the drill bit reaches the critical stroke point for penetration, the axial feed axis is locked, terminating all axial feed movements of the drill bit.

[0012] Maintain the continuous rotating cutting state of the drill bit, switch the steady-state micro-vibration to the impact-strengthened micro-vibration, continuously apply periodic shear stress along the annular plastic slip interface, generate circumferential through micro-cracks inside the slip interface, and use the through micro-cracks to pre-cut the continuous metal connection between the burr matrix and the workpiece base.

[0013] Unlock the axial feed axis and drive the drill bit to cut off the remaining metal at the bottom of the workpiece along the plastic slip interface with penetrating microcracks, so that the burr matrix is ​​completely separated from the workpiece matrix as a whole during the cutting process, without continuous metal stretching and flanging.

[0014] Control the drill bit to retract slightly in the opposite direction, and simultaneously output intermittent pulse micro-vibration to trim the end face of the borehole and remove residual metal debris from the borehole.

[0015] After the hole is finished, the drill bit is fully raised and retracted, the spindle rotation and all micro-vibration outputs are stopped, the workpiece is released from the limit and the unloading is completed.

[0016] Among them, the plastic slip interface is parallel to the bottom surface of the workpiece, and the thin layer of metal left between the plastic slip interface and the bottom surface of the workpiece constitutes the burr matrix.

[0017] In a further embodiment of the present invention, the step of performing rigid limiting clamping on the workpiece and recording the workpiece thickness reference data includes: placing the workpiece to be processed on the machine tool support table, so that the bottom surface of the workpiece processing exit is completely in contact with the rigid support pad, thereby eliminating the suspended deformation space of the bottom surface of the workpiece.

[0018] A multi-directional rigid pressure block is used to press against the upper surface of the workpiece, restricting the axial and radial displacement of the workpiece. This allows all the axial micro-vibration energy to be concentrated on the cutting area of ​​the drill tip, avoiding the loss of micro-vibration energy that leads to incomplete forming of the sliding interface.

[0019] The actual thickness data of the workpiece is entered into the equipment control unit as the criterion for subsequent identification of the critical stroke.

[0020] In a further embodiment of the present invention, the drive drill bit completes the tool setting and positioning, and calibrates the critical stroke point of penetration in conjunction with the workpiece thickness reference, including: driving the spindle to move the drill bit downward to complete the contact tool setting between the drill bit tip and the workpiece upper surface reference;

[0021] The critical axial stroke for bottom-side penetration is calibrated by using the tool tip contact point as the zero point of axial feed and combining it with the entered workpiece thickness data.

[0022] The micro-vibration excitation unit was pre-verified to confirm that the three output modes of steady-state micro-vibration, impact-enhanced micro-vibration, and intermittent pulse micro-vibration could be switched normally, ensuring that the vibration modes of each stage of sliding interface forming, micro-crack prefabrication, and orifice trimming were output normally.

[0023] In a further embodiment of the present invention, the control of the drill bit to perform shallow feed cutting and forming, and synchronous output steady-state axial micro-vibration to extrude and generate an initial plastic slip base inside the workpiece, includes: the spindle driving the drill bit to maintain a constant rotation state, controlling the drill bit to descend at a uniform speed along the axial direction, and completing the shallow cutting and forming of the hole body;

[0024] Synchronously initiate axial steady-state continuous micro-vibration, which continuously acts on the cutting area of ​​the drill tip. Through reciprocating high-frequency extrusion of the metal inside the hole, the metal inside the hole undergoes directional plastic flow, forming a continuous and unbroken initial plastic slip band in the shallow layer of the workpiece.

[0025] Once the drill bit has reached the shallow preset depth, it continues to maintain the feed motion and steady-state micro-vibration output, continuously widening the radial coverage of the plastic slip band, forming an annular slip base that does not penetrate the workpiece and surrounds the inner hole, providing a forming basis for the subsequent complete slip interface.

[0026] In a further embodiment of the present invention, the control of the drill bit to continuously feed and cut the middle layer, maintain steady axial micro-vibration to continuously squeeze the metal below the sliding base, extend and strengthen the sliding base downward, and form a complete annular plastic sliding interface in the area to be penetrated in the workpiece. The plastic sliding interface is used to pre-separate the workpiece base and the thin metal layer below to be burred, including: controlling the drill bit to continuously feed axially at a uniform speed, cutting and removing the middle layer metal of the hole, so that the drill bit gradually approaches the bottom side penetration area of ​​the workpiece;

[0027] The continuous output of steady-state micro-vibration throughout the process repeatedly compresses the metal under the previously formed sliding base, causing the sliding base to extend downward along the direction parallel to the bottom surface of the workpiece.

[0028] At a position where a thin layer of metal is reserved at the bottom of the workpiece, a continuous, complete, and circumferentially uninterrupted annular plastic sliding interface is formed. The plastic sliding interface longitudinally divides the drilling area into an upper rigid workpiece substrate layer and a lower burr matrix layer with only a thin layer remaining, thus achieving pre-independent segmentation of the burr matrix.

[0029] In a further embodiment of the present invention, the real-time reading of the drill bit's axial feed stroke, locking the axial feed axis when the drill bit reaches the critical stroke point, terminating all axial feed movements of the drill bit, maintaining the drill bit's continuous rotational cutting state, switching steady-state micro-vibration to impact-enhanced micro-vibration, continuously applying periodic shear stress along the annular plastic sliding interface, generating circumferential through-cracks inside the sliding interface, and using the through-cracks to pre-cut the continuous metal connection between the burr matrix and the workpiece substrate, includes: real-time monitoring of the drill bit's axial feed stroke, and when the drill bit reaches the pre-calibrated critical stroke point, the control unit locks the feed axis, stopping all axial feed movements of the drill bit, and only retaining the drill bit's rotational movement;

[0030] Maintain the continuous and stable operation of the spindle, keep the drill bit in a constant rotational cutting state, and ensure that the drill tip always keeps in contact with the metal in the sliding interface area.

[0031] The micro-vibration excitation unit is controlled to shut down steady-state micro-vibration and switch to output high-energy impact to enhance micro-vibration, thereby increasing the single axial impact load.

[0032] The impact-enhanced micro-vibration drives the drill tip to generate high-frequency axial reciprocating impact, continuously applying periodic shear stress along the annular plastic slip interface. The shear stress is concentrated on the weak layer of the slip interface, generating circumferential through-cracks around the inner hole inside the slip interface.

[0033] After the circumferential through-crack completely penetrates the plastic slip interface, the burr matrix is ​​only connected to the workpiece matrix through a trace amount of residual metal, thus completely severing the continuous plastic extension channel of the metal.

[0034] In a further embodiment of the present invention, the unlocking of the axial feed axis drives the drill bit to cut off the remaining metal at the bottom of the workpiece along the plastic slip interface with penetrating microcracks, so that the burr matrix is ​​completely separated from the workpiece matrix as the cutting process proceeds, the drill bit is controlled to retract slightly in the reverse direction, and intermittent pulse micro-vibration is output simultaneously to trim the end face of the hole and remove residual metal debris from the hole, including: after identifying that the microcracks at the plastic slip interface are completely penetrating, the feed axis is unlocked and the axial uniform feed motion of the drill bit is restored;

[0035] The drill bit cuts off the remaining thin layer of metal at the bottom along the plastic slip interface with penetrating microcracks. The cracks guide the cutting path to separate along the slip interface, and the burr matrix is ​​separated from the workpiece matrix in one piece synchronously as the cutting process progresses.

[0036] After the drill bit has completely penetrated the bottom surface of the workpiece, control the feed axis to drive the drill bit to retract slightly in the reverse direction by a preset stroke, so that the drill tip stays in the hole opening area;

[0037] The micro-vibration excitation unit switches to output intermittent pulse micro-vibration, which cleans the thin layer of residual metal debris at the edge of the orifice through intermittent impact.

[0038] After the intermittent pulse micro-vibration operation is completed, all micro-vibration outputs are turned off to obtain a drilled structure with a flat end face and no burrs.

[0039] In a further embodiment of the present invention, the control drill bit retracts slightly in the reverse direction and synchronously outputs intermittent pulse micro-vibration to trim the end face of the borehole and remove residual metal debris from the borehole. This includes: the intermittent pulse micro-vibration adopts an intermittent pulse impact output mode, which is different from the steady-state continuous micro-vibration used for forming plastic slip interfaces and the impact-strengthened micro-vibration used for prefabricating circumferential through micro-cracks, and does not adopt a fixed-period sinusoidal continuous vibration.

[0040] The three micro-vibration output modes are automatically switched based on the axial feed stroke position of the drill bit. They do not collect cutting force, vibration amplitude, or image sensor signals as switching conditions, and do not have multi-sensor real-time feedback control.

[0041] In a further embodiment of the present invention, after the hole end face is finished, the drill bit is driven to be fully lifted and retracted, the spindle rotation and all micro-vibration outputs are stopped, the workpiece limit is released and the unloading is completed, including: after the hole end face is finished, the feed axis is controlled to continuously lift the drill bit in the reverse direction so that the drill bit is completely removed from the inner hole of the workpiece, so as to avoid scratching the flat hole during the retraction process.

[0042] Shut down the spindle rotation drive, simultaneously cut off the power supply to the micro-vibration excitation unit, and terminate all machining operations;

[0043] Release the limiting constraint of the rigid pressure block on the workpiece, take out the burr-free drilled workpiece after processing, and complete the single burr-free drilling process.

[0044] A micro-vibration adaptive drilling and burr suppression machining system is used to perform a micro-vibration adaptive drilling and burr suppression machining method; the machining system includes a machine tool host support module, a workpiece rigid limit clamping module, a spindle rotation drive module, an axial feed drive module, a coaxial integrated axial micro-vibration excitation module, and a stroke reference matching control module.

[0045] The workpiece rigid limiting clamping module is equipped with a fitting rigid support pad and a multi-directional rigid pressure block. The rigid support pad is used to support the bottom surface of the workpiece processing exit in the entire area, and the multi-directional rigid pressure block is used to limit the small axial and radial displacements of the workpiece, ensuring that all micro-vibration energy is used to form the plastic sliding interface.

[0046] The spindle rotation drive module is connected to the drill bit holder for driving the drill bit to maintain a constant rotational cutting motion.

[0047] The axial feed drive module works in conjunction with the spindle slide to realize the switching of the entire process of drill bit axial feed, feed lock, small reverse retraction, and full lifting and retraction, and to support the process sequence of locking the pre-splitting burr matrix at critical stroke.

[0048] The coaxial integrated axial micro-vibration excitation module is coaxially integrated inside the spindle tool holder and can independently output three vibration modes: steady-state continuous micro-vibration, impact-enhanced micro-vibration, and intermittent pulse micro-vibration.

[0049] The stroke reference matching control module is electrically connected to the axial feed drive module and the axial micro-vibration excitation module respectively. The stroke reference matching control module calibrates the processing stroke nodes based on the pre-entered workpiece thickness reference. It identifies the processing stage only based on the axial feed stroke position, adaptively matches the drill bit feed action and micro-vibration output mode, and collaboratively completes the entire process of burr suppression processing, including pre-segmenting the burr matrix of the plastic sliding interface, pre-cracking the sliding interface by impact micro-vibration, interface penetration cutting, and end face finishing of the hole.

[0050] The beneficial effects of this invention are:

[0051] 1. A layered steady-state micro-vibration prefabrication method is used to create an annular plastic sliding interface parallel to the bottom surface of the workpiece, pre-separating the workpiece substrate from the burr matrix. Through shallow and middle-level steady-state axial micro-vibration, the metal of the hole wall is continuously compressed, forming a complete annular plastic sliding interface in the area to be penetrated. This constructs a layered isolation structure from within the metal, blocking the basis for continuous plastic extension of the metal during the penetration stage. This method suppresses the generation of continuous, flanged burrs from the root cause of material deformation without relying on reducing cutting force.

[0052] 2. When the drill bit reaches the critical stroke point of penetration, the axial feed is locked, and only the drill bit rotation is maintained. The impact-enhanced micro-vibration is switched to generate circumferential penetrating micro-cracks along the pre-made annular plastic sliding interface, which pre-cuts the continuous metal connection between the burr matrix and the workpiece substrate. Subsequently, the feed is unlocked and cuts off the remaining metal at the bottom along the sliding interface with penetrating micro-cracks. The burr matrix falls off synchronously as a whole with the cutting process, completely avoiding the problem of hole edge flipping caused by metal stretching and tearing at the moment of drilling. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the steps of the method of the present invention. Detailed Implementation

[0054] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0055] In the description of this application, it should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. For ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0056] It should be noted that the terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and are not limited in number; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0057] It should be noted that in the description of this application, the directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" 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 application and simplifying the description. Unless otherwise stated, these directional terms 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, and therefore should not be construed as a limitation on the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0058] It should be noted that, in this application, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0059] This embodiment provides a micro-vibration adaptive drilling burr suppression processing method, including: performing rigid limiting clamping on the workpiece and recording the workpiece thickness reference data;

[0060] The drill bit is driven to complete the tool setting and positioning, and the critical stroke point for penetration is calibrated based on the workpiece thickness reference.

[0061] Control the shallow feed of the drill bit to cut and shape, and simultaneously output steady-state axial micro-vibration to compress and generate an initial plastic slip base inside the workpiece;

[0062] Control the continuous feed cutting of the middle layer of the drill bit, maintain steady axial micro-vibration to continuously squeeze the metal below the slip base, extend and strengthen the slip base downward, form a complete annular plastic slip interface in the area to be penetrated in the workpiece, and use the plastic slip interface to pre-separate the workpiece matrix and the thin metal layer below to be formed with burrs.

[0063] The drill bit's axial feed stroke is read in real time. When the drill bit reaches the critical stroke point, the axial feed axis is locked, terminating all axial feed movements of the drill bit. The drill bit is kept in a continuous rotating cutting state. The steady-state micro-vibration is switched to impact-strengthened micro-vibration. Periodic shear stress is continuously applied along the annular plastic slip interface, generating circumferential through-cracks inside the slip interface. The through-cracks are used to pre-cut the continuous metal connection between the burr matrix and the workpiece substrate.

[0064] Unlock the axial feed axis and drive the drill bit to cut off the remaining metal at the bottom of the workpiece along the plastic slip interface with penetrating microcracks, so that the burr matrix is ​​completely separated from the workpiece matrix as the cutting process proceeds, without continuous metal stretching and flanging; control the drill bit to retract slightly in the reverse direction and output intermittent pulse micro-vibration to trim the end face of the hole and remove residual metal debris from the hole.

[0065] After the hole is finished, the drill bit is fully raised and retracted, the spindle rotation and all micro-vibration outputs are stopped, the workpiece is released from the limit and the unloading is completed.

[0066] Among them, the plastic slip interface is parallel to the bottom surface of the workpiece, and the thin layer of metal left between the plastic slip interface and the bottom surface of the workpiece constitutes the burr matrix.

[0067] Traditional vibratory drilling relies solely on a single sinusoidal vibration throughout the entire process to reduce cutting thrust, which is a passive way to weaken burrs. It lacks metal pre-layering and pre-splitting processes before penetration, and the metal is stretched as a whole at the moment of drilling through, forming continuous flanged burrs.

[0068] The two points that differ from this embodiment are as follows: First, the shallow and middle layers of graded steady-state micro-vibration extrusion metal form a parallel bottom surface annular plastic sliding interface, which longitudinally separates the workpiece matrix and the burr mother body in advance, blocking continuous plastic extension from the root of the metal flow structure.

[0069] Second, the feed is locked at the critical point of penetration, and only the drill bit rotation is retained. The impact micro-vibration is switched to generate circumferential through micro-cracks at the sliding interface. The burr mother body is disconnected in advance, and the metal is cut off along the pre-crack interface. The burr mother body falls off in one piece, completely avoiding metal stretching and flanging.

[0070] In this embodiment, no multi-sensor closed-loop system for cutting force, vision, or other sensors is required throughout the entire process. It relies solely on pre-recorded workpiece thickness calibration stroke to switch vibration modes, simplifying equipment modification and making it resistant to dust and cutting fluid interference. The entire process is completed continuously in a single clamping setup, eliminating the need for offline secondary deburring and significantly improving processing efficiency, hole smoothness, and batch consistency.

[0071] In this embodiment, the rigid limiting clamping of the workpiece and the recording of the workpiece thickness reference data include: placing the workpiece to be processed on the machine tool support table, so that the bottom surface of the workpiece processing exit is completely in contact with the rigid support pad, eliminating the suspended deformation space of the bottom surface of the workpiece.

[0072] A multi-directional rigid pressure block is used to press against the upper surface of the workpiece, restricting the axial and radial displacement of the workpiece. This allows all the axial micro-vibration energy to be concentrated on the cutting area of ​​the drill tip, avoiding the loss of micro-vibration energy that leads to incomplete forming of the sliding interface.

[0073] The actual thickness data of the workpiece is entered into the equipment control unit as the criterion for subsequent identification of the critical stroke.

[0074] Existing clamping methods mostly use single-point support and single-sided clamping, resulting in a suspended area at the bottom of the workpiece. When subjected to micro-vibration, the workpiece undergoes elastic deformation, and a large amount of micro-vibration energy is consumed by the workpiece deformation. This makes it impossible to effectively squeeze the metal on the hole wall to form a continuous and complete plastic sliding interface. The sliding interface is prone to fracture and gaps, and the burr matrix fails to be segmented.

[0075] This solution adopts a combined clamping structure of full-area rigid pad and multi-directional synchronous rigid pressure block limit, which completely locks the workpiece's axial and radial micro-displacements. There is no suspended deformation space on the bottom surface of the workpiece, and all axial micro-vibration energy is precisely concentrated in the cutting area where the drill tip contacts the workpiece, ensuring that subsequent shallow and middle layer steady-state micro-vibrations can compress and form a circumferentially unobstructed annular plastic sliding interface.

[0076] Workpiece thickness data is pre-entered into the control unit as the sole travel determination criterion, eliminating the need for real-time acquisition of machining signals and simplifying control logic. Specifically: the rigid support plate is made of a high-hardness, wear-resistant alloy, with clearance through holes corresponding to the drilling positions to avoid interfering with drill tip penetration; multi-directional rigid pressure blocks are evenly distributed around the workpiece hole machining area, applying clamping force synchronously to prevent the workpiece from tilting to one side; workpiece thickness data is manually entered through the human-machine interface or automatically entered via barcode scanning and stored in the control unit's local storage module, directly accessible throughout the machining process without relying on external real-time sensor acquisition. Therefore: micro-vibration energy utilization is significantly improved, the annular plastic sliding interface is formed completely and uniformly, and the burr suppression effect at the hole openings of batch-processed workpieces is highly consistent; there are no real-time sensor acquisition components, resulting in low equipment modification costs; it is unaffected by machining dust and cutting fluid contamination, ensuring stable and reliable long-term operation.

[0077] In this embodiment, the drive drill bit completes the tool setting pre-positioning and, in conjunction with the workpiece thickness reference, calibrates the critical stroke point for penetration. This includes: driving the spindle to move the drill bit downwards to complete the contact tool setting between the drill bit tip and the workpiece upper surface reference; using the tip contact point as the axial feed zero point, and calibrating the critical axial stroke for penetration on the bottom side of the workpiece in conjunction with the recorded workpiece thickness data; performing mode pre-verification on the micro-vibration excitation unit to confirm that the three output modes of steady-state micro-vibration, impact-enhanced micro-vibration, and intermittent pulse micro-vibration can be switched normally, ensuring normal output of vibration modes in each stage of sliding interface forming, micro-crack pre-forming, and hole trimming.

[0078] Most existing vibratory drilling equipment only has a fixed feed stroke and does not accurately calibrate the critical penetration point based on the actual thickness of the workpiece. This easily leads to premature drilling, incomplete formation of the sliding interface, or excessive feed causing deformation of the workpiece bottom surface. Furthermore, existing equipment only uses a single sinusoidal vibration, making it impossible to switch between different vibration modes in stages. This solution uses the point where the tool tip contacts the upper surface of the workpiece as the absolute feed zero point. It accurately calculates and calibrates the critical penetration stroke based on the actual workpiece thickness, precisely controlling the timing of feed locking to ensure that the sliding interface is formed before entering the pre-cracking process. Three independent micro-vibration modes are pre-verified before processing to ensure that the corresponding vibration output matches different processing stages, mitigating processing failure risks from the outset. Specifically: During the tool setting stage, the spindle moves downward at low speed. After the tool tip contacts the workpiece, a mechanical limit signal is triggered, automatically locking the feed zero point; the critical stroke is equal to the distance from the feed zero point to the bottom surface of the workpiece minus the thickness of the reserved burr matrix; the micro-vibration excitation unit is pre-calibrated by sequentially starting steady-state continuous micro-vibration, impact-enhanced micro-vibration, and intermittent pulse micro-vibration to check whether the vibration output amplitude, impact frequency, and pulse interval are normal. Only after the calibration is normal can the formal cutting process begin.

[0079] Therefore: the critical stroke calibration is accurate, and there will be no defects caused by premature drilling leading to an incomplete slip interface; the three types of vibration modes are verified in advance to avoid vibration mode failure during processing, and the processing yield is significantly improved; the stroke is calibrated based on thickness data, and there is no need to monitor the cutting status in real time throughout the process, and the control logic is simple and stable.

[0080] In this embodiment, the control of the drill bit's shallow feed cutting and shaping, and the simultaneous output of steady-state axial micro-vibration to extrude and generate an initial plastic slip base inside the workpiece, includes: the spindle driving the drill bit to maintain a constant rotation state, controlling the drill bit to descend at a uniform speed along the axial direction to complete the shallow cutting and shaping of the hole; simultaneously starting the axial steady-state continuous micro-vibration, the micro-vibration continuously acting on the cutting area of ​​the drill tip, and through reciprocating high-frequency extrusion of the metal inside the hole, causing the metal inside the hole to undergo directional plastic flow, forming a continuous and unbroken initial plastic slip band in the shallow layer of the workpiece; after the drill bit feeds to the shallow preset depth, the feed motion and steady-state micro-vibration output are continuously maintained, continuously widening the radial coverage range of the plastic slip band, forming an annular slip base that does not penetrate the workpiece and surrounds the inner hole, providing a forming basis for the subsequent complete slip interface.

[0081] Existing vibratory drilling uses uniform vibration parameters throughout the entire process, lacking the step of shallow layered slip base formation. It simply removes metal without actively inducing directional plastic flow of metal to form a layered isolation structure. The key to this embodiment is the simultaneous and continuous output of steady-state micro-vibrations during the shallow cutting stage. Relying on the high-frequency reciprocating axial compression of the drill tip, it actively induces directional plastic flow of metal on the hole wall, forming a continuous and unbroken annular slip base around the inner hole. This provides the foundation for the formation of a complete slip interface through mid-layer extension and strengthening, and is a necessary prerequisite for pre-segmenting the burr matrix.

[0082] Specifically: the shallow layer is preset to a depth between 1 / 3 and 1 / 2 of the total workpiece thickness. During the uniform descent of the drill bit, the micro-vibration excitation unit continuously outputs steady-state micro-vibrations, with the vibration direction strictly along the drill bit axis. The cutting edge of the drill tip continuously presses against the inner wall of the hole, causing the metal to undergo plastic slippage along the direction parallel to the bottom surface of the workpiece, gradually forming a continuous band-shaped slippage structure. After reaching the shallow layer depth, the feed is not stopped and the micro-vibration is not shut off, continuing to widen the radial width of the slippage band, ensuring that the slippage base completely surrounds the inner hole without any local gaps. Therefore, actively inducing the metal to form a continuous annular slippage base provides a reliable foundation for the subsequent formation of a complete plastic slippage interface, achieving layered isolation of the metal inside the workpiece, weakening the continuous extension trend of the metal during penetration from the material structure perspective, and significantly reducing the probability of forming continuous flange burrs.

[0083] In this embodiment, the control of the drill bit's continuous feed cutting in the middle layer, maintaining steady-state axial micro-vibration to continuously compress the metal below the sliding base, extends and strengthens the sliding base downwards, and forms a complete annular plastic sliding interface in the area to be penetrated in the workpiece. The plastic sliding interface pre-separates the workpiece base and the thin metal layer below which burrs are to be formed. This includes: controlling the drill bit to continuously feed axially at a uniform speed, cutting and removing the metal in the middle layer of the hole, so that the drill bit gradually approaches the bottom penetration area of ​​the workpiece; continuously outputting steady-state micro-vibration throughout the process, repeatedly compressing the metal below the previously formed sliding base in the axial direction, causing the sliding base to extend downwards along the direction parallel to the bottom surface of the workpiece; forming a continuous, complete, circumferentially uninterrupted annular plastic sliding interface at a position where a fixed thin metal layer is reserved at the bottom surface of the workpiece. The plastic sliding interface longitudinally separates the drilling area into an upper rigid workpiece base layer and a lower burr matrix layer with only a thin layer thickness, realizing the pre-independent separation of the burr matrix.

[0084] Existing vibratory drilling processes completely lack the layered extrusion forming of a complete annular plastic slip interface and the pre-segmentation of the burr matrix. Current technologies only passively reduce cutting forces and cannot construct a layered metal isolation structure within the workpiece. This step maintains steady-state micro-vibration during the mid-layer feed stage, extending the slip base formed in the shallow layer downwards to form a complete annular slip interface near the bottom surface of the workpiece. This longitudinally divides the machining area into two layers: the base and the independent burr matrix, pre-cutting the structural basis for continuous metal extension without relying on reducing cutting forces to suppress burrs.

[0085] Specifically: the vibration parameters of the middle layer feed process are consistent with the shallow layer steady-state micro-vibration, continuously axially compressing the metal below the sliding base, and the extension direction of the sliding interface is strictly parallel to the bottom surface of the workpiece; a fixed thickness metal layer is reserved between the sliding interface and the bottom surface of the workpiece as the burr matrix. This thin layer does not undergo overall tearing, but only generates penetrating micro-cracks under subsequent impact micro-vibration; the sliding interface is circumferentially complete without gaps, and is continuously distributed around the inner wall of the drill hole in 360°, ensuring that the burr matrix in the entire circumference is pre-separated independently.

[0086] Therefore, by pre-segmenting the burr matrix through a pre-fabricated annular plastic sliding interface, the generation of continuous burrs during the through-stage is blocked from the root cause of metal deformation, eliminating the need for subsequent offline deburring processes, significantly shortening the processing flow and reducing labor and equipment costs; the sliding interface is circumferentially complete, and the burr suppression effect at the orifice of batch processing is uniform and stable.

[0087] In this embodiment, the real-time reading of the drill bit's axial feed stroke, locking the axial feed axis when the drill bit reaches the critical stroke point, terminating all axial feed movements of the drill bit, maintaining the drill bit's continuous rotational cutting state, switching steady-state micro-vibration to impact-enhanced micro-vibration, continuously applying periodic shear stress along the annular plastic sliding interface, generating circumferential through-cracks inside the sliding interface, and using the through-cracks to pre-cut the continuous metal connection between the burr matrix and the workpiece substrate, includes: real-time monitoring of the drill bit's axial feed stroke, and when the drill bit reaches the pre-calibrated critical stroke point, the control unit locks the feed axis, stopping all axial feed movements of the drill bit, and only retaining the drill bit's rotational movement;

[0088] Maintain the continuous and stable operation of the spindle, keep the drill bit in a constant rotational cutting state, and ensure that the drill tip always keeps in contact with the metal in the sliding interface area.

[0089] The micro-vibration excitation unit is controlled to shut down steady-state micro-vibration and switch to output high-energy impact to enhance micro-vibration, thereby increasing the single axial impact load.

[0090] The impact-enhanced micro-vibration drives the drill tip to generate high-frequency axial reciprocating impact, continuously applying periodic shear stress along the annular plastic slip interface. The shear stress is concentrated on the weak layer of the slip interface, generating circumferential through-cracks around the inner hole inside the slip interface.

[0091] After the circumferential through-crack completely penetrates the plastic slip interface, the burr matrix is ​​only connected to the workpiece matrix through a trace amount of residual metal, thus completely severing the continuous plastic extension channel of the metal.

[0092] Current drilling processes involve continuous feed and drilling through the workpiece in one go, lacking steps such as locking the feed at the critical penetration point, rotating without feeding, and switching to impact micro-vibration to pre-create through-cracks. Existing technology directly stretches and tears the metal upon penetration, inevitably forming burrs. This solution completely locks the feed after reaching the critical penetration point, retaining only drill bit rotation. High-energy impact micro-vibration is then used to concentrate shear stress at the pre-created slip interface, generating through-cracks around the inner hole. This pre-disconnects the large-area metal connection between the burr matrix and the substrate, leaving only a small amount of residual material. When the metal is subsequently cut along the crack interface, the burr matrix detaches completely, thoroughly preventing metal stretching and burr formation.

[0093] Specifically: After the feed axis is locked, the spindle speed remains constant, and the drill tip always remains in contact with the metal in the slip interface area, without leaving the working area; the impact-enhanced micro-vibration has a single impact load higher than the steady-state micro-vibration, and the impact energy is concentrated on the weak layer of the plastic slip interface; the shear stress is evenly distributed along the slip interface plane, gradually generating continuous circumferential through-cracks; after the micro-cracks completely penetrate the slip interface, the control unit automatically identifies the pre-crack completion state and enters the next feed cutting process. Therefore: circumferential through-cracks are generated in advance before penetration, which isolates the continuous metal connection between the burr matrix and the workpiece base in advance. During the subsequent cutting process, the burr matrix falls off synchronously as a whole, without continuous metal stretching and flanging, and the end face of the hole is naturally flat, eliminating the need for a secondary deburring process; relying only on the vibration switching of the stroke point, there is no need for multi-sensor closed-loop control, the equipment operates stably, and the modification cost is low.

[0094] In this embodiment, the unlocking of the axial feed axis drives the drill bit to cut off the remaining metal at the bottom of the workpiece along the plastic slip interface with penetrating microcracks, causing the burr matrix to detach from the workpiece matrix as a whole during the cutting process. The drill bit is controlled to retract slightly in the reverse direction, and intermittent pulse micro-vibration is simultaneously output to trim the end face of the hole and remove residual metal debris. This includes: after identifying that the microcracks at the plastic slip interface are fully penetrating, unlocking the feed axis and resuming the uniform axial feed motion of the drill bit; the drill bit cutting off the bottom along the plastic slip interface with penetrating microcracks. The remaining thin layer of metal is separated along the sliding interface by the crack-guided cutting path. The burr matrix is ​​detached from the workpiece matrix in a whole and synchronous manner as the cutting process progresses. After the drill bit completely penetrates the bottom surface of the workpiece, the feed axis is controlled to drive the drill bit to retract slightly in the reverse direction by a preset stroke, so that the drill tip stays in the hole opening area. The micro-vibration excitation unit switches to output intermittent pulse micro-vibration, which cleans the thin layer of metal debris remaining at the edge of the hole opening through intermittent impact. After the intermittent pulse micro-vibration operation is completed, all micro-vibration outputs are turned off, resulting in a drilled structure with a flat end face and no burrs.

[0095] Existing methods involve directly retracting the drill bit after drilling through, leaving metal debris and fine burrs at the hole opening, requiring additional offline grinding and cleaning. Furthermore, existing cutting methods lack a pre-existing crack interface for guidance, resulting in a chaotic cutting path and irregular flanging caused by metal tearing. This new step utilizes the pre-existing through-cracks created in the previous process as a cutting guide path. The drill bit smoothly cuts through the thin layer of metal at the bottom along the sliding interface, removing the burr matrix in one piece. After drilling through, the drill bit is slightly retracted to the hole opening, where gentle intermittent pulse micro-vibration is used to clean away residual debris without scratching the already formed, smooth hole opening. This integrated process of cutting and hole finishing eliminates the need for secondary transfer and processing. Specifically: After the control unit detects the signal indicating complete penetration of the microcrack at the slip interface, it automatically unlocks the feed axis, maintaining a feed speed consistent with the shallow and medium-level cutting speeds; the cutting path extends along the pre-made microcrack, reducing cutting resistance and preventing disordered metal stretching; after the drill bit completely penetrates the bottom surface, it reverses and retracts a small stroke, with the drill tip remaining at the end face of the hole; intermittent pulse micro-vibration uses a discontinuous impact mode, with low single impact energy, only removing loose metal debris without damaging the smooth end face of the hole. Therefore: relying on the pre-made microcrack to guide the cutting path, the burr matrix is ​​removed in one piece without flanging; in-situ synchronous chip trimming at the hole opening is completed, and all machining is completed in a single clamping, eliminating secondary positioning errors and improving machining accuracy and efficiency.

[0096] In this embodiment, the control drill bit retracts slightly in the reverse direction and synchronously outputs intermittent pulse micro-vibration to trim the end face of the borehole and remove residual metal debris. This includes: the intermittent pulse micro-vibration adopts an intermittent pulse impact output mode, which is different from the steady-state continuous micro-vibration used for forming plastic slip interfaces and the impact-strengthened micro-vibration used for prefabricating circumferential through-cracks. It does not use fixed-period sinusoidal continuous vibration. The three micro-vibration output modes are automatically switched by the axial feed stroke position of the drill bit. Cutting force, vibration amplitude, and image sensor signals are not collected as switching judgment conditions, and multi-sensor real-time feedback control is not configured.

[0097] Existing vibration equipment generally uses a single fixed-period sinusoidal vibration, which cannot match the needs of different processes. Vibration mode switching mostly relies on a multi-sensor closed loop composed of cutting force sensors, industrial vision, and vibration acquisition sensors. These sensors are susceptible to contamination by cutting fluid and metal dust, resulting in signal drift, frequent failures, high equipment costs, and complex control logic. This embodiment sets up three completely independent micro-vibrations to match sliding interface forming, micro-crack pre-forming, and hole chip trimming, respectively, abandoning the general sinusoidal vibration. Mode switching is triggered only by pre-calibrated feed stroke points, without collecting any external machining sensor signals throughout the process, and without a multi-sensor closed-loop structure. Specifically: steady-state continuous micro-vibration is an uninterrupted continuous output mode; impact-enhanced micro-vibration is a high-energy concentrated impact mode; and intermittent pulse micro-vibration is an intermittent start-stop pulse output mode. The vibration waveforms and output logic of the three are independent of each other. The control unit internally presets the corresponding stroke range for each stage. When the drill bit feeds to the corresponding range, it automatically switches to the matching vibration mode, without the need to collect machining status data in real time as a basis for judgment. Therefore: phased differentiated vibration output optimizes the processing quality of each process simultaneously; multiple sets of sensor acquisition components are eliminated, significantly reducing equipment modification costs; unaffected by dust and cutting fluid, operational stability and service life are significantly improved; the control logic is simple and adaptable to the modification and implementation of small and medium-sized ordinary CNC drilling machines.

[0098] In this embodiment, after the hole end face is finished, the drill bit is driven to fully lift and retract, the spindle rotation and all micro-vibration outputs are stopped, the workpiece is released from its limit and unloaded. This includes: after the hole end face is finished, the feed axis is controlled to continuously lift the drill bit in the opposite direction so that the drill bit is completely removed from the inner hole of the workpiece to avoid scratching the flat hole during the retraction process; the spindle rotation drive is stopped, the power supply to the micro-vibration excitation unit is simultaneously cut off, and all processing actions are terminated; the limit constraint of the rigid pressure block of the workpiece is released, and the burr-free drilled workpiece is taken out, completing the single burr-free drilling process.

[0099] Traditional machining processes involve rapidly lifting the drill bit after drilling through, which can easily cause the drill bit's cutting edge to scrape the newly formed, smooth hole, resulting in secondary scratches and fine burrs. Furthermore, the vibration unit is not simultaneously shut down after machining, leading to ineffective vibration losses. This solution involves lifting the drill bit in stages until it is completely detached from the inner hole before shutting down the equipment and releasing the limit switch. This protects the smooth end face of the hole throughout the entire process, creating a closed-loop, highly automated machining process. Specifically: After hole finishing, the feed axis continuously lifts the drill bit at a uniform speed until the drill tip is completely detached from the inner hole area on the workpiece's upper surface. Then, the spindle rotation is sequentially shut down, and the power supply to the micro-vibration excitation unit is cut off. The multi-directional rigid clamping force is released, and the workpiece can be removed manually or by a robotic arm. All processes in a single machining cycle are executed continuously and automatically without manual intervention. Therefore: the step-by-step complete drill bit lifting avoids scraping the hole during retraction, ensuring a long-term smooth hole without secondary damage; the entire process operates in a closed-loop, automated manner, reducing manual intervention, adapting to automated batch production lines, and further improving machining consistency and production efficiency.

[0100] Another embodiment provides a micro-vibration adaptive drilling and burr suppression processing system for performing a micro-vibration adaptive drilling and burr suppression processing method; the processing system includes a machine tool host support module, a workpiece rigid limit clamping module, a spindle rotation drive module, an axial feed drive module, a coaxial integrated axial micro-vibration excitation module, and a stroke reference matching control module;

[0101] The workpiece rigid limiting clamping module is equipped with a fitting rigid support pad and a multi-directional rigid pressure block. The rigid support pad is used to support the bottom surface of the workpiece processing exit in the entire area, and the multi-directional rigid pressure block is used to limit the small axial and radial displacements of the workpiece, ensuring that all micro-vibration energy is used to form the plastic sliding interface.

[0102] The spindle rotation drive module is connected to the drill bit holder for driving the drill bit to maintain a constant rotational cutting motion.

[0103] The axial feed drive module works in conjunction with the spindle slide to realize the switching of the entire process of drill bit axial feed, feed lock, small reverse retraction, and full lifting and retraction, and to support the process sequence of locking the pre-splitting burr matrix at critical stroke.

[0104] The coaxial integrated axial micro-vibration excitation module is coaxially integrated inside the spindle tool holder and can independently output three vibration modes: steady-state continuous micro-vibration, impact-enhanced micro-vibration, and intermittent pulse micro-vibration.

[0105] The stroke reference matching control module is electrically connected to the axial feed drive module and the axial micro-vibration excitation module respectively. The stroke reference matching control module calibrates the processing stroke nodes based on the pre-entered workpiece thickness reference. It identifies the processing stage only based on the axial feed stroke position, adaptively matches the drill bit feed action and micro-vibration output mode, and collaboratively completes the entire process of burr suppression processing, including pre-segmenting the burr matrix of the plastic sliding interface, pre-cracking the sliding interface by impact micro-vibration, interface penetration cutting, and end face finishing of the hole.

[0106] Most existing vibratory drilling systems have external vibration devices, only a single sinusoidal vibration output, rely on multiple sensors to collect signals to achieve vibration regulation, lack a rigid full-range limiting clamping structure, and the control system depends on real-time sensing closed loop.

[0107] This results in the workpiece rigid limit clamping module having a detachable and replaceable rigid support plate, adapting to workpieces of different sizes.

[0108] The multi-directional rigid block is equipped with a synchronous clamping cylinder to apply clamping force synchronously.

[0109] The coaxial integrated axial micro-vibration excitation module is embedded inside the tool holder and arranged coaxially with the drill bit. The vibration output direction is strictly along the drill bit axis.

[0110] The stroke reference matching control module has a built-in local storage unit that stores workpiece thickness and stroke node parameters at each stage, eliminating the need for external real-time sensing and acquisition devices.

[0111] The modules communicate via wired signals, avoiding interference from the processing environment that could affect wireless signals. Therefore, the system hardware is fully adapted to the new process of layered prefabricated sliding interfaces and pre-splitting burr-free pre-cutting bodies, stably achieving burr-free drilling; there are no multiple sets of sensor acquisition hardware, resulting in lower equipment manufacturing and maintenance costs; the linkage between modules relies solely on stroke point matching, with simple and stable control logic, resistance to dust and cutting fluid interference, and suitability for long-term continuous batch production in machining workshops.

[0112] The embodiments of this application have been described above with reference to the accompanying drawings. Unless otherwise specified, the embodiments and features in the embodiments of this application can be combined with each other. This application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A micro-vibration adaptive drilling method for burr suppression, characterized in that, include: The workpiece is rigidly clamped and the workpiece thickness reference data is entered. The drill bit is driven to complete the tool setting and positioning, and the critical stroke point for penetration is calibrated based on the workpiece thickness reference. Control the shallow feed of the drill bit to cut and shape, and simultaneously output steady-state axial micro-vibration to compress and generate an initial plastic slip base inside the workpiece; Control the continuous feed cutting of the middle layer of the drill bit, maintain steady axial micro-vibration to continuously squeeze the metal below the slip base, extend and strengthen the slip base downward, form a complete annular plastic slip interface in the area to be penetrated in the workpiece, and use the plastic slip interface to pre-separate the workpiece matrix and the thin metal layer below to be formed with burrs. The drill bit's axial feed stroke is read in real time. When the drill bit reaches the critical stroke point for penetration, the axial feed axis is locked, terminating all axial feed movements of the drill bit. Maintain the continuous rotating cutting state of the drill bit, switch the steady-state micro-vibration to the impact-strengthened micro-vibration, continuously apply periodic shear stress along the annular plastic slip interface, generate circumferential through micro-cracks inside the slip interface, and use the through micro-cracks to pre-cut the continuous metal connection between the burr matrix and the workpiece base. Unlock the axial feed axis and drive the drill bit to cut off the remaining metal at the bottom of the workpiece along the plastic slip interface with penetrating microcracks, so that the burr matrix is ​​completely separated from the workpiece matrix as a whole during the cutting process, without continuous metal stretching and flanging. Control the drill bit to retract slightly in the opposite direction, and simultaneously output intermittent pulse micro-vibration to trim the end face of the borehole and remove residual metal debris from the borehole. After the hole is finished, the drill bit is fully raised and retracted, the spindle rotation and all micro-vibration outputs are stopped, the workpiece is released from the limit and the unloading is completed. Among them, the plastic slip interface is parallel to the bottom surface of the workpiece, and the thin layer of metal left between the plastic slip interface and the bottom surface of the workpiece constitutes the burr matrix.

2. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, The process of performing rigid limiting clamping on the workpiece and recording the workpiece thickness reference data includes: placing the workpiece to be processed on the machine tool support table, so that the bottom surface of the workpiece processing exit is completely in contact with the rigid support pad, eliminating the suspended deformation space of the bottom surface of the workpiece. A multi-directional rigid pressure block is used to press against the upper surface of the workpiece, restricting the axial and radial displacement of the workpiece. This allows all the axial micro-vibration energy to be concentrated on the cutting area of ​​the drill tip, avoiding the loss of micro-vibration energy that leads to incomplete forming of the sliding interface. The actual thickness data of the workpiece is entered into the equipment control unit as the criterion for subsequent identification of the critical stroke.

3. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, The drive drill bit completes the tool setting and positioning, and calibrates the critical stroke point of penetration based on the workpiece thickness reference, including: driving the spindle to move the drill bit downward to complete the contact tool setting between the drill bit tip and the workpiece upper surface reference; The critical axial stroke for bottom-side penetration is calibrated by using the tool tip contact point as the zero point of axial feed and combining it with the entered workpiece thickness data. The micro-vibration excitation unit was pre-verified to confirm that the three output modes of steady-state micro-vibration, impact-enhanced micro-vibration, and intermittent pulse micro-vibration could be switched normally, ensuring that the vibration modes of each stage of sliding interface forming, micro-crack prefabrication, and orifice trimming were output normally.

4. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, The control drill bit shallow feed cutting and shaping, synchronous output steady-state axial micro-vibration, and extrusion to generate an initial plastic slip base inside the workpiece, includes: the spindle drives the drill bit to maintain a constant rotation state, and controls the drill bit to descend at a uniform speed along the axial direction to complete the shallow cutting and shaping of the hole body. Synchronously initiate axial steady-state continuous micro-vibration, which continuously acts on the cutting area of ​​the drill tip. Through reciprocating high-frequency extrusion of the metal inside the hole, the metal inside the hole undergoes directional plastic flow, forming a continuous and unbroken initial plastic slip band in the shallow layer of the workpiece. Once the drill bit has reached the shallow preset depth, it continues to maintain the feed motion and steady-state micro-vibration output, continuously widening the radial coverage of the plastic slip band, forming an annular slip base that does not penetrate the workpiece and surrounds the inner hole, providing a forming basis for the subsequent complete slip interface.

5. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, The control drill bit continuously feeds and cuts in the middle layer, maintaining steady axial micro-vibration to continuously compress the metal below the sliding base, extending and strengthening the sliding base downwards, forming a complete annular plastic sliding interface in the area to be penetrated in the workpiece, and using the plastic sliding interface to pre-separate the workpiece base and the thin metal layer below to be burred, including: controlling the drill bit to continuously feed axially at a uniform speed, cutting and removing the metal in the middle layer of the hole, so that the drill bit gradually approaches the bottom side penetration area of ​​the workpiece; The continuous output of steady-state micro-vibration throughout the process repeatedly compresses the metal under the previously formed sliding base, causing the sliding base to extend downward along the direction parallel to the bottom surface of the workpiece. At a position where a thin layer of metal is reserved at the bottom of the workpiece, a continuous, complete, and circumferentially uninterrupted annular plastic sliding interface is formed. The plastic sliding interface longitudinally divides the drilling area into an upper rigid workpiece substrate layer and a lower burr matrix layer with only a thin layer remaining, thus achieving pre-independent segmentation of the burr matrix.

6. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, The real-time reading of the drill bit's axial feed stroke, locking the axial feed axis when the drill bit reaches the critical stroke point, terminating all axial feed movements of the drill bit, maintaining the drill bit's continuous rotational cutting state, switching steady-state micro-vibration to impact-enhanced micro-vibration, continuously applying periodic shear stress along the annular plastic slip interface, generating circumferential through-cracks inside the slip interface, and using the through-cracks to pre-cut the continuous metal connection between the burr matrix and the workpiece substrate, includes: real-time monitoring of the drill bit's axial feed stroke, and when the drill bit reaches the pre-calibrated critical stroke point, the control unit locks the feed axis, stopping all axial feed movements of the drill bit, and only retaining the drill bit's rotational movement; Maintain the continuous and stable operation of the spindle, keep the drill bit in a constant rotational cutting state, and ensure that the drill tip always keeps in contact with the metal in the sliding interface area. The micro-vibration excitation unit is controlled to shut down steady-state micro-vibration and switch to output high-energy impact to enhance micro-vibration, thereby increasing the single axial impact load. The impact-enhanced micro-vibration drives the drill tip to generate high-frequency axial reciprocating impact, continuously applying periodic shear stress along the annular plastic slip interface. The shear stress is concentrated on the weak layer of the slip interface, generating circumferential through-cracks around the inner hole inside the slip interface. After the circumferential through-crack completely penetrates the plastic slip interface, the burr matrix is ​​only connected to the workpiece matrix through a trace amount of residual metal, thus completely severing the continuous plastic extension channel of the metal.

7. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, The unlocked axial feed axis drives the drill bit to cut off the remaining metal at the bottom of the workpiece along the plastic slip interface with penetrating microcracks, so that the burr matrix is ​​completely separated from the workpiece matrix as the cutting process proceeds. The drill bit is controlled to retract slightly in the reverse direction, and intermittent pulse micro-vibration is output simultaneously to trim the end face of the hole and remove residual metal debris from the hole. This includes: after identifying that the microcracks at the plastic slip interface are completely penetrating, the feed axis is unlocked and the axial uniform feed motion of the drill bit is restored. The drill bit cuts off the remaining thin layer of metal at the bottom along the plastic slip interface with penetrating microcracks. The cracks guide the cutting path to separate along the slip interface, and the burr matrix is ​​separated from the workpiece matrix in one piece synchronously as the cutting process progresses. After the drill bit has completely penetrated the bottom surface of the workpiece, control the feed axis to drive the drill bit to retract slightly in the reverse direction by a preset stroke, so that the drill tip stays in the hole opening area; The micro-vibration excitation unit switches to output intermittent pulse micro-vibration, which cleans the thin layer of residual metal debris at the edge of the orifice through intermittent impact. After the intermittent pulse micro-vibration operation is completed, all micro-vibration outputs are turned off to obtain a drilled structure with a flat end face and no burrs.

8. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, The control drill bit retracts slightly in the reverse direction and outputs intermittent pulse micro-vibration to trim the end face of the hole and remove residual metal debris from the hole. This includes: the intermittent pulse micro-vibration adopts an intermittent pulse impact output mode, which is different from the steady-state continuous micro-vibration used for forming plastic slip interfaces and the impact-strengthened micro-vibration used for prefabricating circumferential through micro-cracks. It does not use fixed-period sinusoidal continuous vibration. The three micro-vibration output modes are automatically switched based on the axial feed stroke position of the drill bit. They do not collect cutting force, vibration amplitude, or image sensor signals as switching conditions, and do not have multi-sensor real-time feedback control.

9. The micro-vibration adaptive drilling and burr suppression method according to claim 1, characterized in that, After the hole end face is finished, the drill bit is driven to be fully raised and retracted, the spindle rotation and all micro-vibration outputs are stopped, the workpiece limit is released and the unloading is completed. This includes: after the hole end face is finished, the feed axis is controlled to continuously raise the drill bit in the opposite direction so that the drill bit is completely removed from the inner hole of the workpiece to avoid scratching the flat hole during the retraction process. Shut down the spindle rotation drive, simultaneously cut off the power supply to the micro-vibration excitation unit, and terminate all machining operations; Release the limiting constraint of the rigid pressure block on the workpiece, take out the burr-free drilled workpiece after processing, and complete the single burr-free drilling process.

10. A micro-vibration adaptive drilling and burr suppression system, characterized in that, The machining system is used to perform the micro-vibration adaptive drilling and deburring method according to any one of claims 1 to 9; the machining system includes a machine tool host support module, a workpiece rigid limit clamping module, a spindle rotation drive module, an axial feed drive module, a coaxial integrated axial micro-vibration excitation module, and a stroke reference matching control module. The workpiece rigid limiting clamping module is equipped with a fitting rigid support pad and a multi-directional rigid pressure block. The rigid support pad is used to support the bottom surface of the workpiece processing exit in the entire area, and the multi-directional rigid pressure block is used to limit the small axial and radial displacements of the workpiece, ensuring that all micro-vibration energy is used to form the plastic sliding interface. The spindle rotation drive module is connected to the drill bit holder for driving the drill bit to maintain a constant rotational cutting motion. The axial feed drive module works in conjunction with the spindle slide to realize the switching of the entire process of drill bit axial feed, feed lock, small reverse retraction, and full lifting and retraction, and to support the process sequence of locking the pre-splitting burr matrix at critical stroke. The coaxial integrated axial micro-vibration excitation module is coaxially integrated inside the spindle tool holder and can independently output three vibration modes: steady-state continuous micro-vibration, impact-enhanced micro-vibration, and intermittent pulse micro-vibration. The stroke reference matching control module is electrically connected to the axial feed drive module and the axial micro-vibration excitation module respectively. The stroke reference matching control module calibrates the processing stroke nodes based on the pre-entered workpiece thickness reference. It identifies the processing stage only based on the axial feed stroke position, adaptively matches the drill bit feed action and micro-vibration output mode, and collaboratively completes the entire process of burr suppression processing, including pre-segmenting the burr matrix of the plastic sliding interface, pre-cracking the sliding interface by impact micro-vibration, interface penetration cutting, and end face finishing of the hole.

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