A workpiece pre-machining calibration device and a calibration method thereof

Abstract

The present application relates to a kind of workpiece machining calibration device and method, belong to part machining positioning technical field, solve the low efficiency of complex part positioning alignment, the problem of poor accuracy.The present application includes calibration reference piece, 3D scanning equipment, coordinate comparison module, processing table and coordinate acquisition module;Calibration reference piece is detachably fixed in the key datum position of the surface of workpiece to be made;Calibration reference piece is used to be pasted on the first surface of workpiece to be made;3D scanning equipment obtains scanning model;Coordinate comparison module is used to compare scanning model with original design model, determine the first coordinate of calibration reference piece in the first coordinate system of original design model;Coordinate acquisition module is used to obtain the second coordinate of calibration reference piece in the second coordinate system of processing table.The device of the present application effectively solves the problem of low positioning alignment efficiency and poor accuracy, improves production efficiency and machining accuracy.

Description

Technical Field

[0001] This invention relates to the field of machining calibration technology, and in particular to a workpiece pre-machining calibration device and calibration method. Background Technology

[0002] Irregularly shaped workpieces manufactured through additive manufacturing, die casting, or blank cutting often have rough, uneven surfaces and irregular shapes, posing a challenge to precise alignment during the pre-finishing process. Current technologies for pre-processing alignment of such workpieces often employ pre-set clamping structures or select easily identifiable original shapes on the workpiece surface as references. This requires milling a reference plane first, followed by re-alignment using that plane as a reference. Such alignment methods suffer from cumbersome clamping operations, complex reference conversion processes, and long dimensional transfer paths, easily leading to accumulated errors. This not only reduces the final machining accuracy of the workpiece but also severely impacts production efficiency.

[0003] To overcome the aforementioned technical bottlenecks, this invention provides a workpiece pre-processing calibration device. By utilizing the spherical geometric features of the calibration reference part to establish a precise alignment benchmark, and in conjunction with a multi-degree-of-freedom clamping mechanism, it achieves efficient and precise alignment of irregularly shaped workpieces before processing, successfully solving the technical problems of low efficiency and insufficient accuracy of existing alignment methods. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a workpiece pre-processing calibration device to solve one of the problems in the prior art, such as repeated clamping and positioning, complicated reference conversion process, difficulty in ensuring positioning accuracy, and excessive processing errors.

[0005] The present invention provides a workpiece pre-processing calibration device, which includes a calibration reference, a 3D scanning device, a coordinate comparison module, a processing table, and a coordinate acquisition module.

[0006] The calibration reference piece is detachably fixed to the key reference position on the surface of the workpiece to be manufactured;

[0007] A 3D scanning device is used to scan the workpiece to be manufactured with the calibration reference piece attached thereon to obtain a scanned model;

[0008] The coordinate comparison module is used to call the original design model of the workpiece to be manufactured, compare the scanned model with the original design model, and determine the first coordinate of the calibration reference part on the first coordinate system of the original design model;

[0009] A processing table is used to fix the workpiece to be manufactured with the calibration reference piece attached thereto.

[0010] The coordinate acquisition module is used to acquire the second coordinates of the calibration reference piece in the second coordinate system where the processing table is located;

[0011] Specifically, the position of the workpiece to be manufactured on the processing table is adjusted so that the second coordinate coincides with the first coordinate.

[0012] Furthermore, the processing table also includes a connector disposed on the second surface of the workpiece to be processed.

[0013] Furthermore, the processing table also includes a retaining guide groove, which includes a lower movable groove and an upper movable groove.

[0014] Furthermore, the processing table also includes a bead end retainer, which includes a lower movable part and a second slider. The lower movable part is slidably disposed on the lower movable groove, and the second slider is slidably disposed on the upper movable groove.

[0015] Furthermore, the second slider is used to fix the connector.

[0016] Furthermore, the processing table also includes a support assembly, the upper end of which is disposed on the lower movable part.

[0017] Furthermore, the support assembly includes a support rod and a support rod bracket, the support rod being threadedly connected to the support rod bracket, and the height of the support assembly can be adjusted by changing the connection position between the support rod and the support rod bracket.

[0018] Furthermore, the processing table also includes a support base, which includes a lower fixed base and a top movable base;

[0019] The lower end of the support component is mounted on the top movable seat.

[0020] Furthermore, a T-shaped groove is provided on the upper end face of the top movable seat, and the T-shaped grooves are arranged in a matrix on the top movable seat;

[0021] The support component can be movably disposed in the T-shaped groove.

[0022] Furthermore, the processing table also includes a base frame, and the lower end fixing seat is disposed on the base frame.

[0023] In another aspect, the present invention provides a calibration method for workpiece processing, wherein the above-mentioned workpiece pre-processing calibration device is used for calibration.

[0024] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0025] (1) The workpiece pre-processing calibration device of the present invention includes a calibration reference, a 3D scanning device, a coordinate comparison module, a processing table, and a coordinate acquisition module. The calibration reference is used to be pasted onto the first surface of the workpiece to be processed; the 3D scanning device is used to scan the workpiece to be processed with the calibration reference pasted thereon to acquire a scanned model; the coordinate comparison module is used to call the original design model of the workpiece to be processed and compare the scanned model with the original design model to determine the first coordinate of the calibration reference on the original design model; the processing table is used to fix the workpiece to be processed with the calibration reference pasted thereon; the coordinate acquisition module is used to acquire the second coordinate of the calibration reference in the coordinate system of the processing table. By establishing a precise correlation benchmark between the workpiece to be processed and the design model through the calibration reference, and with the synergistic effect of the 3D scanning device, the coordinate comparison module, and the coordinate acquisition module, an integrated calibration process of scanning-comparison-positioning-adjustment is realized. Without the need for multiple clamping and complex reference transfer in traditional processes, positioning is completed directly through coordinate coincidence adjustment, which greatly reduces the accumulation of deviations and significantly improves calibration accuracy. At the same time, it simplifies the calibration operation steps, shortens the preparation time before processing, effectively solves the problem of difficult positioning of irregular and rough surface workpieces, and improves production efficiency and processing consistency.

[0026] (2) The workpiece pre-processing calibration device of the present invention provides a connector on the second surface of the workpiece to be processed, so that the clamping operation and the positioning function of the calibration reference on the first surface are independent of each other and do not interfere with each other. The connector provides a dedicated clamping reference for the workpiece to be processed, avoiding the reference offset caused by directly clamping the calibration reference, while enhancing the clamping stability of the workpiece on the processing table, preventing the workpiece from loosening or shifting during the calibration process, ensuring the accuracy of subsequent coordinate acquisition and adjustment, and improving the collaborative reliability of clamping and positioning.

[0027] (3) The workpiece pre-processing calibration device of the present invention attaches a calibration reference piece to the workpiece to be processed and obtains a scanning model by combining 3D scanning. Based on the original design model, the scanning model and the design model are accurately matched in a way that the workpiece to be processed completely covers the original design model. Then, the theoretical position of the calibration reference piece in the design reference coordinate system, i.e., the first coordinate, is determined. After the workpiece to be processed is placed on the processing table, the actual position of the calibration reference piece in the processing table coordinate system, i.e., the second coordinate, is obtained. The tooling and turntable are adjusted to make the two sets of coordinates coincide, thereby achieving rapid and accurate positioning, which greatly shortens the alignment time and improves processing efficiency and accuracy. By quickly aligning the position of the workpiece to be processed on the processing table, the workpiece to be processed can be subjected to high-precision cutting processing according to the design mold at this position, ensuring that the finished product is highly consistent with the design model. At the same time, this method reduces the dependence on the operator's experience, improves the process repeatability and automation level, and is suitable for high-efficiency production scenarios of multi-variety, small-batch complex parts.

[0028] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained from what is particularly pointed out in the description and drawings. Attached Figure Description

[0029] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0030] Figure 1 This is one of the structural schematic diagrams of the workpiece pre-processing calibration device described in Example 1;

[0031] Figure 2 This is a second schematic diagram of the workpiece pre-processing calibration device described in Example 1;

[0032] Figure 3 This is a schematic diagram of the support component in Example 1;

[0033] Figure 4 This is a schematic diagram of the lower movable part in Example 1;

[0034] Figure 5 This is a schematic diagram of the structure of the second slider in Example 1.

[0035] Figure label:

[0036] 1-Workpiece to be manufactured

[0037] 2-Calibration reference piece;

[0038] 3-Processing table, 31-Connector, 311-Connecting end, 312-Connecting rod, 313-Guide ball, 32-Ball end retaining seat, 321-Lower movable part, 3211-First retaining member, 3212-Second retaining member, 3213-Lower connecting rod, 3214-Lower pushing member, 3215-Locking member, 322-Second slider, 3221-Third retaining member, 3222-Fourth retaining member, 3223-Upper connecting rod, 322 4-Upper pusher, 3225-Upper locking member, 33-Fixing guide groove, 331-Support rod, 332-Lower movable groove, 333-Upper movable groove, 34-Support assembly, 341-Support rod, 3411-Hinge, 342-Support rod bracket, 3421-Bottom connection, 3422-Fixing plate, 35-Support seat, 351-Lower fixed seat, 352-Top movable seat, 3521-Moving slide, 36-Equipment base frame. Detailed Implementation

[0039] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0040] Example 1

[0041] This invention provides a workpiece pre-processing calibration device. This embodiment aims to solve the problems of low positioning accuracy and poor processing efficiency caused by the need for multiple clamping operations and numerous reference transfer steps in the prior art. Figure 1 As shown, the system includes: a calibration reference 2, a 3D scanning device, a coordinate comparison module, a processing table 3, and a coordinate acquisition module; the calibration reference 2 is used to be pasted onto the first surface of the workpiece to be manufactured; the 3D scanning device is used to scan the workpiece to be manufactured with the calibration reference 2 pasted thereon to obtain a scanned model; the coordinate comparison module is used to call the original design model of the workpiece to be manufactured 1, and compare the scanned model with the original design model to determine the first coordinate of the calibration reference 2 in the first coordinate system of the original design model; the processing table 3 is used to fix the workpiece to be manufactured 1 with the calibration reference 2 pasted thereon; the coordinate acquisition module is used to obtain the second coordinate of the calibration reference 2 in the second coordinate system of the processing table 3; wherein, the position of the workpiece to be manufactured 1 on the processing table 3 is adjusted so that the second coordinate coincides with the first coordinate.

[0042] Furthermore, ensuring spatial alignment between the scanned model and the original design model is fundamental to guaranteeing calibration accuracy. The coordinate comparison module's principle is to spatially register the scanned model with the original design model, ensuring that the scanned model completely encompasses the original design model. The scanned model is then placed within the coordinate system of the original design model, and the first coordinate of the calibration reference 2 within the first coordinate system of the original design model is determined. This ensures that the two have consistent geometric relationships in space, achieving precise alignment.

[0043] The workpiece pre-processing calibration device described in this embodiment uses a 3D scanning device to scan a model of the workpiece 1 to be manufactured, with a calibration reference 2 attached. This establishes a reference link between the scanned model and the original design model. While the shape and size of the workpiece 1 may deviate, the dimensions of the calibration reference 2 are fixed. The calibration reference 2 can be accurately identified and positioned in the scanned model. The first coordinate of its theoretical coordinate position in the original design model is determined by the coordinate comparison module, serving as the sole basis for reference transfer. Simultaneously, the coordinate acquisition module acquires the second coordinate of the calibration reference 2 in the coordinate system of the machining table 3. By comparing the two sets of coordinate data, the spatial pose deviation of the workpiece 1 is calculated, and the adjustment mechanism is driven to perform precise correction, ensuring that the second coordinate completely coincides with the first coordinate. This process does not rely on the workpiece's own geometric features, avoiding accuracy loss due to clamping errors or reference conversion, and significantly improving positioning repeatability and processing efficiency. The entire calibration process is highly automated, suitable for complex curved surfaces and multi-process continuous machining scenarios, effectively ensuring the dimensional consistency and geometric accuracy of the final part.

[0044] Furthermore, the calibration reference 2 is adhered to the outer end face of the workpiece 1 using adhesive. Multiple calibration references 2 are used, ensuring that every three references define a plane. The attachment positions of the calibration references 2 avoid the clamping and machining areas. The calibration reference 2 is the core reference component for positioning and alignment. During the 3D scanning stage, the calibration reference 2 serves as a prominent feature point of the scanned model, quickly matching the original design model and obtaining the first coordinate. During the positioning stage on the machining table 3, the center of the calibration reference 2 is measured using the probe of the machining table 3 to obtain the second coordinate. By adjusting the position of the workpiece 1 to make the first and second coordinates of the calibration reference 2 coincide, precise positioning of the workpiece 1 can be achieved.

[0045] Furthermore, in order to better stabilize and fix the workpiece 1 to be manufactured with the calibration reference 2 attached to the processing table 3, the processing table 3 in this embodiment also includes a connector 31, which is attached to the second surface of the workpiece 1 and is distributed in a non-coplanar manner with the calibration reference 2.

[0046] Furthermore, to enable the processing table 3 to match workpieces 1 with different structures and shapes, the connector 31 needs to be able to adjust its connection angle and position according to the structure of the workpiece 1. The connector 31 includes a connecting end 311, a connecting shaft 312, and a guide ball 313. The guide ball 313 is hinged to the processing table 3. By changing the angle of the connector 31, the connection position between the connector 31 and the workpiece 1 can be adjusted to adapt to workpieces 1 with different structures or shapes. The connecting end 311 and the guide ball 313 are located at both ends of the connecting shaft 312. The connecting end 311 is glued to the surface of the workpiece 1 in a preset clamping area (3 in total, distributed at different positions on the outer end face of the workpiece 1) with adhesive. The clamping area is arranged in a triangular pattern to ensure force balance and stable positioning. The connecting shaft 312 is made of high-strength lightweight material, which has both rigidity and shock resistance, effectively transmitting clamping force and reducing deformation accumulation.

[0047] Furthermore, the processing table 3 also includes a retaining guide groove 33, a bead end retaining seat 32, a supporting component 34, and a supporting seat 35; the bead end retaining seat 32 is slidably installed on the retaining guide groove 33, and can move freely along the guide rail and lock its position to adapt to workpieces 1 of different sizes; the retaining guide groove 33 is disposed on the supporting component 34, and the supporting component 34 is vertically disposed on the supporting seat 35.

[0048] To further ensure the support function of the workpiece 1 and to adjust the X and Y axis coordinates of the workpiece 1 in the second coordinate system where the processing table 3 is located, the support 35 has a rotatable structure. Specifically, the support 35 includes a lower fixed seat 351 and a top movable seat 352. The top movable seat 352 is connected to the lower fixed seat 351 through a rotating mechanism, which can achieve free rotation in the horizontal plane. The rotating mechanism includes a servo motor and a gear set to ensure precise control of the rotation angle and repeatability of the positioning accuracy. The servo motor receives instructions from the CNC system to drive the precision gear set to rotate, thereby rotating the top movable seat 352 at a set angle to adjust the azimuth angle of the workpiece 1. The servo motor drives the gear set to rotate, thereby rotating the top movable seat 352 precisely at a preset angle to achieve precise orientation adjustment of the workpiece 1 in the horizontal plane. During the rotation, the encoder feeds back the rotation angle to the CNC system in real time, forming a closed-loop control to ensure that the rotation positioning error is less than 0.01°. When the top movable seat 352 reaches the target angle, the braking device automatically locks the rotating mechanism to prevent positional deviation caused by cutting force during processing. The top movable seat 352 is provided with a support component 34 for supporting the workpiece 1 to be manufactured. Its top surface is provided with a movable slide 3521, which is arranged in a matrix on the top surface of the top movable seat 352.

[0049] The top movable seat 352 of the support 35 has the function of rotating around its own vertical axis. During the positioning and adjustment stage, the tooling support, the holding guide groove 33 and the workpiece 1 to be made can be rotated synchronously by rotating the table surface, thereby adjusting the X and Y axis coordinates of the calibration reference 2 on the workpiece 1 in the machining table coordinate system. With the height adjustment of the support rod 341, the second coordinate of the calibration reference 2 is aligned with the first coordinate in the XY plane. It is the core execution component for positioning and adjustment in the XY direction.

[0050] To more accurately adjust the Z-axis height of the workpiece 1 in the coordinate system of the machining table 3, a height-adjustable support assembly 34 is provided on the support seat 35. The support assembly 34 specifically includes a support rod 341, a support rod bracket 342, and tooling support fastening bolts. The support rod bracket 342 is located on the movable slide 3521 on the top surface of the top movable seat 352. The support rod bracket 342 includes a bottom connecting part 3421, a fixed plate 3422, and a support rod. The bottom connecting part 3421 is located within the movable slide 3521 and can move and be positioned along the groove within the movable slide 3521. The fixed plate 3422 is fastened to the top surface of the top movable seat 352 by the tooling support fastening bolts. The support rod is vertically mounted on the top movable seat 352. The moving seat 352; the support rod is a hollow round tube with one open end, and the inner wall of the support rod is threaded. The support rod 341 is screwed into the thread on the inner wall of the support rod. By rotating and adjusting the height of the support screw, the vertical lifting of the top positioning point of the tooling support can be realized, and the adjustment accuracy can reach 0.01mm. Multiple tooling supports can be adjusted in coordination to compensate for the parallelism error between the bottom surface of the workpiece 1 and the rotating table surface. The upper end of the support rod 341 is provided with a hinge part 3411, which is matched and set in the first groove of the lower movable part 321 on the fixed guide groove 33 to achieve precise positioning. The ball head and the first groove are in point contact, which effectively eliminates the assembly stress caused by over-positioning and ensures that the degree of freedom of the fixed guide groove 33 is controllable during the spatial posture adjustment process.

[0051] Furthermore, multiple support components 34 are included, for example, three support components 34 are set in a triangular layout and distributed within the projection range of the center of gravity of the workpiece 1 to ensure balanced support force; the hinge part 3411 of each support component 34 and the corresponding groove of the holding guide groove 33 achieve point contact cooperation, forming a three-point positioning system in space, which greatly reduces the deformation error caused by multi-point constraints. The three support rods 341 are evenly distributed along the table surface of the support base 35 to form a three-point support structure: the support rods 341 can be rotated to raise and lower in the vertical direction (Z-axis), thereby adjusting the height of the workpiece 1 to match the Z-axis coordinates of the calibration reference 2 in the design model; when the height is adjusted to the correct position, tightening the tooling support fastening bolts can lock the position of the support rods 341, preventing the workpiece 1 from shifting in the Z-axis direction due to gravity or vibration during processing, which is the core adjustment component for Z-axis height positioning.

[0052] To improve the adjustability of the machining table 3 in the X, Y and Z axis directions, the worktable 3 also includes a guide groove 33 and a bead end retainer 32. The bead end retainer 32 can move on the guide groove 33 to adjust the horizontal position of the connector 31 and the support assembly 34, and accordingly adjust the position of the workpiece 1 to be manufactured in the second coordinate system X, Y and Z axes.

[0053] The retaining guide groove 33 includes a support rod 331, a lower movable groove 332, and an upper movable groove 333; there are three support rods 331, which form a Y-shaped structure. The support rods 331 are provided with a lower movable groove 332 and an upper movable groove 333. The lower movable groove 332 is located below the upper movable groove 333. The lower movable part 321 is provided in the lower movable groove 332 and can slide along it. The upper movable part 322 is provided in the upper movable groove 333 and can slide along it.

[0054] The bead end retainer 32 includes a lower movable part 321 and an upper movable part 322. The lower movable part 321 is slidably disposed on the lower movable groove 332, and the upper movable part 322 is slidably disposed on the upper movable groove 333.

[0055] The lower movable part 321 is provided with a clamping mechanism for fixing the hinge part 3411 of the support rod 341. The lower movable part 321 includes a first fastener 3211, a second fastener 3212, a lower connecting rod 3213, a lower pushing member 3214, and a locking member 3215. Curved grooves are formed at opposite positions on the first fastener 3211 and the second fastener 3212. When the first fastener 3211 and the second fastener 3212 are arranged opposite each other, the two curved grooves are spliced ​​to form a first spherical clamping cavity for clamping one end of the connecting member 31. The clamping cavity is positioned downwards toward the hinge portion 3411. The first clamping member 3211 and the second clamping member 3212 are connected by the lower connecting rod 3213. The clamping force can be controlled by adjusting the lower pushing member 3214, so as to achieve reliable locking and fine-tuning release of the hinge portion 3411. The locking member 3215 is used to lock the adjustment state to prevent vibration and loosening. This structure provides stable mechanical constraints while ensuring point contact positioning accuracy, ensuring the positional consistency of the holding guide groove 33 in the X, Y, and Z directions, and meeting the requirements for repeatability positioning accuracy in high-precision machining. The first fastening hole is provided on the side wall of the first fastening member 3211 and the second fastening member 3212. The first fastening hole is connected to the first spherical clamping cavity, so that the screw of the lower push member 3214 can extend into the cavity and act on the hinge part 3411. The clamping force can be precisely adjusted by rotating the tightening bolt, so as to achieve stress-free clamping and flexible release of the hinge part 3411 and avoid micro-deformation or damage caused by excessive tightness. The lower connecting rod 3213 and the locking member 3215 form a double anti-loosening structure, which can maintain clamping stability in the vibration environment. This design ensures high repeatability positioning accuracy between the holding guide groove 33 and the supporting component 34. With the three-point support layout, it effectively suppresses multi-degree-of-freedom disturbances and improves the overall rigidity.

[0056] To achieve the adjustability of the fixed connector 31 and to lock the fixed connector 31, this embodiment further provides a clamping mechanism on the upper movable part 322 for fixing the connector 31. The upper movable part 322 includes a third fastener 3221, a fourth fastener 3222, an upper connecting rod 3223, an upper pushing member 3224, and an upper locking member 3225. The third fastener 3221 and the second fastener 3212 have curved grooves at opposite positions. The third fastener 3221 and the fourth fastener... When the three fasteners 3222 and 3222 are positioned relative to each other, the two curved grooves are joined together to form a second spherical clamping cavity for holding one end of the connector 31. Fixed through holes are provided at the relative positions of the third fastener 3221 and the fourth fastener 3222. The upper pusher 3224 passes through the fixed through holes on the third fastener 3221 and the fourth fastener 3222, and cooperates with the fixing nut to lock and release the clamping force, firmly fixing the connector 31 in the upper movable part 322, ensuring that it does not loosen or shift during processing. By adjusting the preload of the clamping block's tightening bolts, connectors 31 of different diameters can be accommodated, improving adaptability and clamping reliability.

[0057] Furthermore, second fastening holes are provided on the side walls of the third fastener 3221 and the fourth fastener 3222, which connect to the second spherical clamping cavity. After the connecting piece 31 is placed in the second spherical clamping cavity, the clamping block tightening bolt is screwed in to fix the connecting piece 31 between the third fastener 3221 and the fourth fastener 3222, further enhancing clamping stability. At the same time, the axis of the second tightening bolt is aligned with the center of the second spherical clamping cavity, ensuring uniform force application and avoiding local stress concentration that could lead to deformation or damage to the connecting piece 31, thus ensuring positioning accuracy and consistency in repeated clamping. The entire support and clamping system works in concert to achieve precise positioning and reliable fixation of the workpiece 1 in space with six degrees of freedom, providing a fundamental guarantee for high-precision machining.

[0058] Furthermore, the processing table 3 also includes a base frame 36. The base frame 36 serves as the bottom-level load-bearing component of the entire positioning fixture system. The support seat 35 is rotatably mounted on the base frame 36 and placed as a whole on the worktable of the processing table. The base frame 36 provides a rigid foundation reference for the entire device. Its flat top surface ensures the horizontal levelness of the support seat 35. Simultaneously, its robust structure can offset vibrations during the clamping and adjustment of the workpiece 1, preventing positioning accuracy deviations caused by an unstable foundation. It serves as a stable platform for the subsequent installation and adjustment of all components.

[0059] Example 2

[0060] This embodiment, based on embodiment 1, also includes a calibration and verification module, which is used to check and verify the alignment result of the workpiece 1 to be manufactured, to avoid clamping errors caused by human operation or environmental factors, and to ensure the accuracy of the machining datum.

[0061] Four calibration reference pieces 2 are set on the workpiece 1 to be manufactured, ensuring that every three calibration reference pieces 2 are distributed in the same plane. Three calibration reference pieces 2 are used for alignment calibration, and the fourth calibration reference piece 2 is used for independent verification of the calibration results. The fourth calibration reference piece 2 does not participate in the initial alignment process.

[0062] The workpiece pre-processing calibration device described in this embodiment also includes a calibration verification module;

[0063] A 3D scanning device is used to scan the workpiece 1 to be manufactured with the calibration reference 2 attached thereon to obtain a scanned model; the scanned model contains the spatial coordinate data of the four calibration references 2.

[0064] The coordinate comparison module is used to call the original design model of the workpiece 1 to be manufactured, and compare the scanned model with the original design model to determine the first coordinates of the four calibration reference parts 2 on the first coordinate system of the original design model. The scanned model is then placed within the original design model, ensuring that it completely covers the original design model. That is, when the scanned model covers the original design model, the workpiece 1 corresponding to the scanned model can be processed according to the diameter of the original actual model to obtain the desired product. The coordinate comparison module determines the first coordinates of the four calibration reference parts 2 on the first coordinate system of the original design model.

[0065] The coordinate acquisition module is used to acquire the second coordinates of the calibration reference 2 in the second coordinate system where the processing table 3 is located; and to acquire the second coordinates of the four calibration references 2 in the second coordinate system where the processing table 3 is located through a 3D scanning device.

[0066] By adjusting the height of the support component 34, the position of the lower movable part 321 on the lower movable groove 332, the position of the upper movable part 322 on the upper movable groove 333, and the angle of the rotating support 35, the second coordinates corresponding to the three calibration reference parts 2 used for alignment are made to completely coincide with the first coordinates, thereby achieving accurate reproduction of the spatial posture of the workpiece 1 to be manufactured.

[0067] In actual production and calibration processes, deviations in the pasting position or scanning and identification errors of calibration reference 2 may occur, causing the alignment results to deviate from the theoretical coordinates. In such cases, the second coordinate of the fourth calibration reference 2 needs to be independently verified by the calibration verification module and compared with the theoretical coordinates in the first coordinate system to determine the accuracy of the alignment process. If the second coordinate of the fourth calibration reference 2 coincides with the first coordinate, the alignment process is accurate and can proceed to the subsequent processing stage. If the deviation exceeds the preset tolerance threshold, it is determined that there is a clamping or measurement error. The parameters of the support component 34 need to be readjusted, and the scanning, comparison, and verification process needs to be repeated until the coordinates of all calibration reference 2 are completely matched within the allowable error range, ensuring that the spatial positioning accuracy of the workpiece 1 meets the high-requirement processing conditions. The calibration verification module verifies the spatial position deviation of the fourth calibration reference 2 on each workpiece 1, ensuring that the spatial posture of each workpiece 1 on the processing table 3 is accurately reproduced, effectively avoiding processing inaccuracies caused by accumulated errors. Through the independent verification mechanism of the fourth calibration reference 2, the system can identify clamping offset, scanning noise or data registration anomalies in real time, ensuring that the alignment results are reliable and trustworthy every time.

[0068] Example 3

[0069] This embodiment provides a method for calibrating a workpiece using the workpiece pre-processing calibration device of Embodiment 1 or Embodiment 2, including the following steps:

[0070] Step 1: Attach calibration reference 2 to the surface of the workpiece 1 to be manufactured; arrange 4 calibration reference 2 on the outer end face of the workpiece 1 according to the structure and processing characteristics of the workpiece 1 to be manufactured, so that every 3 calibration reference 2 can independently determine a plane to realize the positioning of the workpiece 1 to be manufactured. The calibration reference 2 is bonded to the outer end face of the workpiece 1 to be manufactured with adhesive.

[0071] Step 2: Perform a 3D scan on the workpiece 1 to be manufactured with the calibration reference 2 attached thereon to obtain a scan model; the scan model is the workpiece 1 to be manufactured and the scan model of the calibration reference 2 attached thereon.

[0072] Step 3: Obtain the original design model of the workpiece 1 to be manufactured, and compare the scanned model with the original design model to determine the first coordinate of the calibration reference 2 on the original design model.

[0073] Comparing the scanned model with the original design model is fundamental to the alignment and calibration of the workpiece 1 to be manufactured. The specific steps are as follows:

[0074] Step 3.1 Construct a design datum coordinate system. With the center of a datum surface of the design model as the origin O, the two perpendicular edges of the datum surface as the X and Y axes, and the direction perpendicular to the datum surface as the Z axis, establish an XYZ rectangular coordinate system. Constructing the design datum coordinate system provides a unified and standardized datum framework for determining the coordinates of calibration reference part 2, avoiding coordinate calculation deviations caused by unclear datums. Setting the origin at the center of the design model's datum surface and the X and Y axes as the two perpendicular edges directly aligns with the part's design datum, ensuring that the first coordinate of calibration reference part 2 can be accurately mapped to the design datum coordinate system. This unified datum design lays the foundation for accurate comparison between the subsequent scanning model and the design model, further improving the accuracy and stability of the entire positioning and alignment process, and is particularly suitable for high-precision machining scenarios with stringent datum requirements.

[0075] Step 3.2 Place the scanning model into the design reference coordinate system, ensuring that the scanning model completely covers the original design mold. Placing the scanning model into the design reference coordinate system and ensuring complete coverage of the original design model effectively eliminates the misalignment problem between the scanning model and the design model in the coordinate system. Simultaneously, with the scanning model completely covering the original design mold, when the workpiece 1 is in its current position, processing the workpiece 1 can completely remove material according to the processing path of the original design model, obtaining the final desired product. Under the above conditions, determine the first coordinate of the calibration reference 2 in the design reference coordinate system.

[0076] In order to better fix the workpiece 1 to be manufactured on the processing table 3 and obtain the coordinate information of the workpiece 1 to be manufactured in the second coordinate system of the processing table 3, the following steps are adopted in this embodiment:

[0077] Step 4: Place the workpiece 1 to be manufactured, with the calibration reference piece 2 attached, onto the processing table 3.

[0078] Step 4.1, the step of setting the connector 31 on the workpiece 1 to be manufactured.

[0079] Step 4.2, adjusting the position of the bead end retainer 32 on the processing table 3.

[0080] Step 4.3 is the step of setting the connector 31 onto the bead end retainer 32.

[0081] Based on the connectors 31 attached to the surface of the workpiece 1, adjust the position of the bead end retaining seats 32 installed on the holding guide groove 33, install the connectors 31 into the corresponding bead end retaining seats 32, install the connectors 31 into the spherical groove between the clamping block and the clamping block, tighten the clamping block fastening bolts, and simultaneously tighten the clamping block top bolts, thereby achieving the installation and fixation of the workpiece 1 on the holding guide groove 33. Further, the number of connectors 31 is 3.

[0082] Step 5: Obtain the second coordinates of the calibration reference 2 in the coordinate system of the machining table 3. After installing the workpiece 1 with the calibration reference 2 attached onto the machining table 3, establish the coordinate system of the machining table 3 with the base of the machining table 3 as the reference, and determine the second coordinates of the calibration reference 2 in the coordinate system of the machining table 3.

[0083] Step 6: Adjust the position of the workpiece 1 to be processed on the processing table 3 so that the second coordinate of the calibration reference 2 coincides with the first coordinate.

[0084] In the workpiece pre-processing calibration device described in this invention, a reference datum is established between the scanned model and the original design model through the calibration reference 2. Compared with traditional methods such as manual scribing and table alignment, this significantly improves the accuracy of positioning and alignment. The combination of 3D scanning and model comparison can quickly lock the design coordinates of the calibration reference 2, and then the adjustment is completed through coordinate matching in the coordinate system of the machining table 3, avoiding subjective errors caused by manual operation. At the same time, the entire process does not require complex tooling fixture adaptation, making it more flexible in adapting to workpieces 1 with different structures, significantly shortening the positioning and alignment time, and improving the efficiency of processing preparation.

[0085] Furthermore, in step 6, the position of the workpiece 1 to be manufactured on the processing table 3 is adjusted so that the second coordinate of the calibration reference 2 coincides with the first coordinate. Step 6 includes the following steps:

[0086] If the posture of the workpiece 1 to be processed is adjusted quickly, it will affect the efficiency of calibration and processing. In this embodiment, the height of the support component 34 on the processing table 3 is adjusted so that the Z-axis coordinate value of the calibration reference 2 in the second coordinate system is consistent with the Z-axis coordinate value in the first coordinate system. The height of the three support rods 341 is adjusted. At the same time, considering that the projection distance between the three support points on the XOY plane changes when the position of the three support rods 341 is adjusted, the position of the bead end clamping seat 32 installed on the tooling support 6 relative to the holding guide groove 33 and the position of the tooling support relative to the support seat 35 need to be adjusted simultaneously to ensure that there is no interference. The support seat 35 of the processing table 3 is rotated so that the X-axis and Y-axis coordinate values ​​of the calibration reference 2 in the second coordinate system are consistent with the X-axis and Y-axis coordinate values ​​in the first coordinate system.

[0087] Furthermore, the process includes step 7, verifying the accuracy of the position of the workpiece 1 on the processing table 3. This involves verifying the accuracy of the position of the workpiece 1 on the processing table 3. The second coordinate of the fourth calibration reference 2 and its first coordinate are obtained. If the second coordinate of the fourth calibration reference 2 coincides with the first coordinate, then the position of the workpiece 1 on the processing table 3 is verified to meet the processing requirements; if the second coordinate of the fourth calibration reference 2 does not coincide with the first coordinate, then the position of the workpiece 1 on the processing table 3 is verified to not meet the processing requirements.

[0088] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A workpiece pre-processing calibration device, characterized in that, It includes a calibration reference (2), a 3D scanning device, a coordinate comparison module, a processing table (3), and a coordinate acquisition module; The calibration reference piece (2) is detachably fixed to the key reference position on the surface of the workpiece (1); A 3D scanning device is used to scan the workpiece (1) to be manufactured with the calibration reference piece (2) attached thereon to obtain a scanned model; The coordinate comparison module is used to call the original design model of the workpiece (1) to be manufactured, and compare the scanning model with the original design model to determine the first coordinate of the calibration reference (2) on the first coordinate system of the original design model; A processing table (3) is used to fix the workpiece (1) to be manufactured on which the calibration reference piece (2) is attached; the processing table (3) includes a connector (31), a bead end retainer (32), a retaining guide groove (33), a support assembly (34), and a support base (35); the connector (31) is disposed on the second surface of the workpiece (1); the bead end retainer (32) includes a lower movable part (321) and an upper movable part (322), the upper movable part (322) being used to fix the connector (31); the retaining guide groove (33) includes a lower movable groove (332) and an upper movable groove (333); the lower movable part (321) is slidably disposed in the lower movable groove (332). The upper movable part (322) is slidably disposed on the upper movable groove (333); the upper end of the support assembly (34) is disposed on the lower movable part (321); the support assembly (34) includes a support rod (341) and a support rod bracket (342), the support rod (341) and the support rod bracket (342) are threadedly connected, and the height of the support assembly (34) is adjusted by changing the connection position of the support rod (341) and the support rod bracket (342); the support seat (35) includes a lower fixed seat (351) and a top movable seat (352); the lower end of the support assembly (34) is disposed on the top movable seat (352); The coordinate acquisition module is used to acquire the second coordinates of the calibration reference (2) in the second coordinate system where the processing table is located; Among them, the position of the workpiece (1) to be manufactured is adjusted on the processing table so that the second coordinate coincides with the first coordinate.

2. The workpiece pre-processing calibration device according to claim 1, characterized in that, The upper end face of the top movable seat (352) is provided with a T-shaped groove, and the T-shaped grooves are arranged in a matrix on the top movable seat (352); The support component (34) is movably disposed in the T-shaped groove.

3. A calibration method for workpiece machining, wherein the workpiece pre-machining calibration device described in claim 1 or 2 is used for calibration.

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