Magnetic grid force sensing dual-mode intelligent clamping tool

Abstract

The invention discloses a magnetic grid force sensing bimodal intelligent clamping tool which comprises a base body, a plurality of clamping units arranged in the circumferential direction of the base body, a driving mechanism, a magnetic grid measuring mechanism, a force sensing detection mechanism and an intelligent control module, each clamping unit comprises a base claw and a clamping claw installed on the base claw, the base claw is slidably arranged in the base body, and the force sensing detection mechanism is arranged on the base claw. The motor is in driving connection with the driving mechanism; the magnetic grid measuring mechanism comprises a magnetic grid ruler and a magnetic head, the magnetic grid ruler is embedded in the base claw in the moving direction of the base claw, and the magnetic head is correspondingly installed on the base body and corresponds to the magnetic grid ruler in position; the force sensing detection mechanism is embedded in the clamping face of the clamping jaw, the intelligent control module is installed on the base body and located beside the magnetic head, and the intelligent control module is electrically connected with the magnetic head and the force sensing detection mechanism. The method has the beneficial effects that the purposes of bimodal measurement and good adaptability are achieved.

Description

Technical Field

[0001] This invention relates to the field of mechanical clamping fixture technology, specifically to a magnetic grating force-sensing dual-mode intelligent clamping fixture. Background Technology

[0002] In machining and precision manufacturing, workpiece clamping fixtures are core equipment for ensuring machining accuracy and improving production efficiency. Their clamping accuracy, stability, and level of intelligence directly affect the machining quality of the workpiece. Currently, most existing clamping fixtures use a single detection method for clamping control, such as detecting clamping pressure only through force sensors or clamping position only through displacement sensors. This results in incomplete detection and low control accuracy: detecting only pressure cannot determine whether the clamping position has shifted, which can easily lead to workpiece machining deviations; detecting only displacement cannot determine whether the clamping pressure is too high, which can easily cause workpiece damage. They are especially unsuitable for clamping easily deformable or irregular precision workpieces.

[0003] Meanwhile, existing clamping fixtures mostly use integrated drives, making it difficult to achieve decoupled control of radial sliding and axial fine adjustment of the base jaws. This results in poor adaptability and an inability to meet the clamping needs of workpieces with different specifications and contours. Their control logic is relatively simple, often a single "detection-simple adjustment" mode, lacking the integration of digital technology for precise prediction and adaptive adjustment, leading to low levels of intelligence. Some intelligent fixtures use photoelectric encoders to measure displacement, but photoelectric elements are sensitive to harsh conditions such as oil, cutting fluid, and metal chips, resulting in poor reliability. Conventional clamping fixtures mostly use open-loop control, unable to adjust clamping parameters in real time according to the actual state of the workpiece, making it difficult to handle the clamping needs of complex workpieces such as irregularly shaped or thin-walled parts. Furthermore, existing displacement measurement mechanisms mostly use traditional grating measurements, which have limitations in accuracy, susceptibility to interference, and short service life, making it difficult to meet the requirements of high-precision clamping. Integrating sensing elements with the clamping structure often results in bulky components and complex wiring, affecting the overall performance and applicability of the fixture. Summary of the Invention

[0004] The present invention aims to address the problems of limited measurement methods and poor adaptability mentioned in the background art, and provides a dual-modal measurement and adaptable magnetic grating force sensing dual-modal intelligent clamping fixture.

[0005] A dual-mode intelligent clamping fixture with magnetic grating and force sensing includes a base body, multiple clamping units arranged circumferentially thereon, a drive mechanism, a magnetic grating measurement mechanism, a force sensing detection mechanism, and an intelligent control module. Each clamping unit includes a base jaw and a chuck mounted on the base jaw. The base jaw is slidably disposed within the base body and driven by the drive mechanism. The magnetic grating measurement mechanism includes a magnetic grating ruler and a magnetic head. The magnetic grating ruler is embedded in the base jaw along the movement direction of the base jaw, and the magnetic head is correspondingly mounted on the base body, corresponding to the position of the magnetic grating ruler. The force sensing detection mechanism is embedded in the clamping surface of the chuck. The intelligent control module is mounted on the base body and located beside the magnetic head, and is electrically connected to both the magnetic head and the force sensing detection mechanism.

[0006] By integrating the magnetic grating measurement mechanism (magnetic grating ruler + magnetic head) and the force sensing mechanism into the clamping fixture, a "displacement-pressure" dual-modal sensing system is constructed. The intelligent control module is located next to the magnetic head, which can shorten the signal transmission distance and reduce electromagnetic interference. The magnetic grating measurement can accurately know the real-time position of the gripper, and the force sensing can sense the clamping pressure on the workpiece. The combination of the two provides a comprehensive data foundation for subsequent intelligent control. Compared with the single mode, it significantly improves the comprehensiveness and accuracy of the fixture's perception of the workpiece status, achieving the goal of dual-modal measurement and good adaptability.

[0007] Preferably, the radial side of the base claw is provided with a magnetic grating groove, and the magnetic grating ruler is fixedly installed in the magnetic grating groove. The top of the base body is provided with a base claw groove and a magnetic head through groove that match the base claw along the circumferential direction. The inner side of the magnetic head through groove corresponds to the base claw groove, and the magnetic head is installed in the magnetic head through groove. The magnetic head and the magnetic grating ruler are arranged on the same side and maintain a non-contact sensing gap. Through the structural design of the magnetic grating groove and the magnetic head through groove, the precise alignment and installation of the magnetic grating ruler and the magnetic head are achieved. The magnetic head and the magnetic grating ruler are arranged on the same side and maintain a non-contact sensing gap, which not only ensures the accuracy of displacement measurement, but also avoids mechanical wear. At the same time, it can effectively resist the interference of contaminants such as oil and iron filings, and improve the reliability and service life of the tooling under harsh working conditions.

[0008] Preferably, the base body also has a locking slot located outside the magnetic head through slot, a locking block is installed in the locking slot, and a control chamber is provided inside the locking block, in which the intelligent control module is encapsulated. Encapsulating the intelligent control module in the control chamber of the locking block achieves compact integration of the control unit and the mechanical body. The module is located beside the magnetic head, shortening the signal transmission distance and reducing electromagnetic interference. The detachable structure of the locking block also facilitates the inspection and upgrading of the control module, improving the overall maintenance convenience of the machine.

[0009] Preferably, the force sensing mechanism is a miniature force sensor array, which is uniformly embedded in the clamping surface of the jaws. It can simultaneously collect local pressure data from multiple contact points. The force sensing mechanism and the magnetic grating measurement mechanism form a dual-modal feedback, providing the intelligent control module with a comprehensive judgment of the clamping state. Using a miniature force sensor array allows for the collection of local pressure data from multiple points on the clamping surface, rather than just obtaining the total clamping force. The fixture can sense microscopic states such as workpiece tilt and abnormal local contact, providing a more precise basis for judging whether the workpiece is clamped stably. After fusion with displacement data, a more comprehensive workpiece posture judgment can be formed.

[0010] Preferably, the intelligent control module has a built-in workpiece digital twin database for receiving displacement data from the magnetic head and pressure data from the micro-force sensor array, and comparing and analyzing them with the workpiece digital twin model in real time. When abnormal clamping pressure or displacement is detected as inconsistent with the preset model, the intelligent control module sends a command to the drive mechanism to dynamically adjust the motion parameters of the clamping unit, forming a closed-loop control. By using the built-in workpiece digital twin database in the intelligent control module, real-time comparison and analysis of dual-modal detection data and the digital twin model can be achieved, enabling rapid identification of problems such as abnormal clamping pressure and displacement deviation. The system actively makes dynamic adjustments, forming a closed-loop control of "perception-analysis-decision-execution," improving the intelligence level and adaptability of the clamping process, and adapting to the clamping requirements of workpieces of different specifications and materials.

[0011] Preferably, the clamping units are arranged in four pairs, with each pair of clamping units having a corresponding magnetic grating measuring mechanism on its base jaws. The four clamping units are divided into a first pair of clamping units and a second pair of clamping units. The intelligent control module controls the four clamping units to center in a preset order: first, the first pair of clamping units contacts the workpiece for centering, and then the second pair of clamping units centers. During the centering process of the second pair of clamping units, if the workpiece position needs to be adjusted, the intelligent control module controls the first pair of clamping units to automatically follow and retreat until all jaws conform to the workpiece contour. By setting the clamping units in a four-pair structure and controlling the four clamping units to center in a preset order through the intelligent control module, centering the opposite jaws first, then the other pair of jaws, and allowing the first pair of clamping units to automatically follow and retreat when the second pair of clamping units moves, all jaws can naturally conform to the outer contour of the workpiece. This is especially suitable for irregularly shaped workpieces or scenarios with high centering accuracy requirements, avoiding the drawbacks of traditional four-jaw chucks that require repeated manual adjustments.

[0012] Preferably, the drive mechanism includes a central shaft, a drive ring, a decoupled drive assembly, and an external actuator. The central shaft is rotatably supported at the center of the base body. The external actuator is installed on the outside of the base body, electrically connected to the intelligent control module, and drively connected to the central shaft. The drive ring is sleeved on the central shaft and rotates synchronously with the central shaft. The decoupled drive assembly connects the drive ring and the clamping unit, and is used to convert the rotational motion of the drive ring into the radial motion of the clamping unit. The intelligent control module drives the central shaft to rotate by controlling the external actuator, thereby driving the drive ring to rotate, and realizing the dynamic adjustment of the motion parameters of the clamping unit. The external actuator is preferably a servo motor, which is installed on the outside of the base body. The output shaft of the servo motor is connected to the bottom of the central shaft through a coupling. Through the design of the decoupled drive assembly, a single drive source (rotation of the central shaft) can simultaneously drive the gripper to perform both radial sliding and axial fine adjustment movements. Compared with the traditional integrated drive method, the radial feed and axial height of the base gripper can be precisely controlled separately, adapting to workpieces of different thicknesses and contours, avoiding clamping deviations caused by drive interference, and improving clamping accuracy and operational flexibility.

[0013] Preferably, the decoupled drive assembly includes at least two sets of sliding blocks, each set of sliding blocks including at least one sliding block, the sliding blocks being connected to the base claw drive, wherein the first set of sliding blocks and the second set of sliding blocks have opposite oblique angles;

[0014] The intelligent control module dynamically adjusts the motion parameters of the clamping unit by controlling the rotation angle and direction of the drive ring. Two sets of sliding blocks with opposite angles are used to achieve decoupled motion control. By precisely controlling the rotation angle and direction of the drive ring through the intelligent control module, the radial and axial movements of the grippers can be adjusted independently or in combination. The structure is simple and the control precision is high, enabling the fixture to perform fine-tuning of the clamping posture for different workpiece characteristics.

[0015] Preferably, the system further includes a reset spring mechanism, which comprises multiple reset springs, each disposed on one side of each sliding block, to provide a reset force to the sliding block. The reset spring mechanism assists the sliding block in quickly resetting when the drive ring rotates in the opposite direction, eliminating transmission backlash and improving the sensitivity of motion response and repeatability. Simultaneously, the preload provided by the springs ensures that the sliding block and drive ring maintain good contact at all times, preventing motion jamming.

[0016] Preferably, the magnetic scale is a high-precision magnetic scale with a magnetic pole pitch of less than 0.5 mm, the magnetic head has a resolution at the micrometer level, and the intelligent control module includes a signal processing circuit that uses interpolation subdivision technology to improve the measurement accuracy to the sub-micrometer level. By using a high-precision magnetic scale (magnetic pole pitch <0.5 mm) combined with interpolation subdivision technology, the measurement accuracy is improved from the micrometer level to the sub-micrometer level, meeting the stringent requirements for gripper positioning accuracy in the precision machining field.

[0017] The beneficial effects of this invention are as follows: By coordinating the magnetic grating measurement mechanism and the force sensing detection mechanism, dual-dimensional detection of clamping displacement and clamping pressure is achieved, which solves the defect that the existing single detection method cannot fully determine the clamping state; the intelligent control module has a built-in workpiece digital twin database, which compares the dual-modal detection data with the digital twin model in real time, which can quickly identify clamping abnormalities and dynamically adjust the clamping parameters to adapt to workpieces of different specifications and materials.

[0018] The device employs a decoupled drive assembly to achieve precise decoupling between the radial sliding and axial fine-tuning of the base claw, combined with the orderly centering control of four paired clamping units. It utilizes a high-precision magnetic scale with interpolation subdivision technology to achieve sub-micron level measurement accuracy. The intelligent control module adopts a card-block packaging design, and the magnetic scale measurement mechanism is embedded, resulting in a compact and reasonable overall structure. This facilitates equipment inspection and replacement, reduces maintenance costs, and achieves dual-modal measurement with good adaptability. Attached Figure Description

[0019] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0020] Figure 1 This is a schematic diagram of the structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0022] Figure 3 This is a schematic diagram of the drive component.

[0023] Figure 4 A schematic diagram of the various slots opened on the base body;

[0024] Figure 5 This is a schematic diagram of the intelligent control module installed inside the card.

[0025] Figure 6 A schematic diagram of a force sensing mechanism installed on the gripper surface.

[0026] Among them, 1. Base body, 11. Base claw groove, 12. Magnetic head through groove, 13. Clamping block opening, 2. Clamping unit, 21. Base claw, 211. Magnetic grating groove, 22. Clamping claw, 3. Drive mechanism, 31. Central shaft, 32. Drive ring, 33. Decoupled drive assembly, 331. Sliding block, 4. Magnetic grating measurement mechanism, 41. Magnetic grating ruler, 42. Magnetic head, 5. Force sensing detection mechanism, 51. Miniature force sensor array, 6. Intelligent control module, 7. Clamping block, 71. Control chamber, 8. Reset spring mechanism, 81. Reset spring. Detailed Implementation

[0027] The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the embodiments.

[0028] In the description of this invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer" and "vertical" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0029] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; or they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0030] Furthermore, in the description of this invention, unless otherwise stated, "multiple", "multiple groups", and "multiple roots" mean two or more.

[0031] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments;

[0032] Example 1:

[0033] like Figure 1 As shown, a magnetic grating force-sensing dual-mode intelligent clamping fixture includes a base body 1, four sets of clamping units 2, a drive mechanism 3, four sets of magnetic grating measurement mechanisms 4, a force-sensing detection mechanism 5, an intelligent control module 6, and external actuators.

[0034] like Figure 2As shown, four sets of clamping units 2 are evenly arranged along the circumference of the base body 1, and are set in pairs, namely the first pair of clamping units and the second pair of clamping units. Each set of clamping units 2 includes a base jaw 21 and a chuck jaw 22. The chuck jaw 22 is slidably mounted on the top of the base jaw 21. The chuck jaw 22 can slide radially on the base jaw 21 to increase the adjustable space for workpiece clamping. The base jaw 21 is set in the base jaw groove 11 opened in the base body 1, and the base jaw 21 is driven and connected to the drive mechanism 3 to realize radial sliding.

[0035] The magnetic grating measurement mechanism 4 corresponds one-to-one with the clamping unit 2. Each set of magnetic grating measurement mechanisms 4 includes a magnetic grating ruler 41 and a magnetic head 42. A magnetic grating groove 211 is opened on the radial side of the base claw 21. The magnetic grating ruler 41 is fixedly embedded in the magnetic grating groove 211 by adhesive. The length direction of the magnetic grating ruler 41 is consistent with the sliding direction of the base claw 21. A high-precision magnetic grating ruler 41 with a magnetic pole pitch of 0.3mm is adopted. A magnetic head through groove 12 corresponding to the base claw groove 11 is opened on the top of the base body 1 along the circumferential direction. The inner side of the magnetic head through groove 12 is connected to the base claw groove 11. The magnetic head 42 can be directly fixedly installed in the magnetic head through groove 12 without the need for an auxiliary structure. The magnetic head 42 and the magnetic grating ruler 41 are set on the same side, and a non-contact sensing gap of 0.1-0.3mm is maintained between them. The magnetic head 42 adopts a magnetic head with a resolution of 1μm and is used to collect the displacement data of the base claw 21 in real time.

[0036] like Figure 6 As shown, the force sensing mechanism 5 is a miniature force sensor array 51, consisting of four miniature pressure sensors, which are evenly embedded in the clamping surface of the jaw 22. The detection accuracy of the miniature pressure sensors is 0.01N, and they can simultaneously collect local pressure data at four points where the jaw 22 contacts the workpiece. The force sensing mechanism 5 is electrically connected to the intelligent control module 6 through wires to transmit pressure data to the intelligent control module 6.

[0037] like Figure 2 and Figure 4 As shown, the base body 1 also has four locking slots 13, which are located on the outside of each magnetic head through slot 12. A locking block 7 is fixedly installed in the locking slot 13. The locking block 7 has a sealed control chamber 71 inside. The intelligent control module 6 is encapsulated in the control chamber 71 and is located next to the magnetic head 42, which shortens the connection line with the magnetic head 42. The intelligent control module 6 is electrically connected to the magnetic head 42 and the force sensing mechanism 5 respectively. The electrical connection is achieved through wires to ensure stable signal transmission and is used to receive displacement data and pressure data.

[0038] like Figure 3As shown, the drive mechanism 3 includes a central shaft 31, a drive ring 32, a decoupled drive assembly 33, and an external actuator. The central shaft 31 is rotatably supported at the center of the base body 1. The external actuator is a servo motor, which is installed outside the base body 1. The output shaft of the servo motor is connected to the central shaft 31 via a coupling, and the servo motor is electrically connected to the intelligent control module 6 and controlled by the intelligent control module 6. The drive ring 32 is sleeved on the central shaft 31 via a flat key and rotates synchronously with the central shaft 31. The decoupled drive assembly 33 includes four sliding blocks 331. The sliding blocks 331 are connected to the base claw 21 via pins. The first set of sliding blocks and the second set of sliding blocks have opposite angles (30° and -30° respectively), which are used to convert the rotational motion of the drive ring 32 into the radial motion of the base claw 21.

[0039] like Figure 2 As shown, the reset spring mechanism 8 includes eight reset springs 81. Each sliding block 331 has one reset spring 81 on each side, which is used to provide a stable reset force to the sliding block 331 and realize the automatic reset of the clamping unit 2.

[0040] like Figure 5 As shown, the intelligent control module 6 has a built-in workpiece digital twin database, which stores three-dimensional models of different workpiece types, preset clamping displacement parameters, and pressure parameters. The intelligent control module 6 also has a signal processing circuit, which uses interpolation subdivision technology to improve the accuracy of the displacement data fed back by the magnetic head 42 to 0.1μm (submicron level). After receiving the displacement data fed back by the magnetic head 42 and the pressure data fed back by the force sensing mechanism 5, the intelligent control module 6 compares and analyzes them with the preset parameters in the workpiece digital twin model in real time. When the clamping pressure is detected to be outside the preset range (such as greater than the preset maximum value or less than the preset minimum value), or the displacement does not match the preset model, the intelligent control module 6 immediately sends a command to the servo motor to adjust the speed and direction of the servo motor, thereby driving the central shaft 31 and the drive ring 32 to rotate. The sliding displacement and speed of the base jaw 21 are adjusted through the decoupled drive component 33 to realize the dynamic adjustment of the clamping parameters and form a closed-loop control.

[0041] This embodiment is suitable for clamping precision semiconductor workpieces, with a clamping accuracy of up to 0.1μm and a pressure control accuracy of up to 0.01N.

[0042] The working process and principle are as follows:

[0043] Initialization preparation: Place the workpiece to be clamped at the center of the base body 1, and call the preset parameters of the corresponding workpiece (including clamping displacement range, pressure range, centering sequence, etc.) in the workpiece digital twin database through the intelligent control module 6 to complete the initialization setting of the tooling.

[0044] Centering and clamping: The intelligent control module 6 sends a command to the external actuator (servo motor) of the drive mechanism 3 to start the servo motor and drive the central shaft 31 to rotate. The central shaft 31 drives the drive ring 32 to rotate synchronously. The drive ring 32 converts the rotational motion into the radial motion of the clamping unit 2 through the decoupled drive assembly 33 (sliding block 331). The clamping unit 2 is controlled to center in a preset sequence: First, the first pair of clamping units is controlled to move radially. When the jaws 22 contact the workpiece, the force sensing mechanism 5 detects the pressure signal and the magnetic grating measuring mechanism 4 detects the current displacement signal. Both are transmitted synchronously to the intelligent control module 6. The intelligent control module 6 determines that the first pair of clamping units has completed the centering and positioning. Then, the second pair of clamping units is controlled to move radially. During the centering process of the second pair of clamping units, if the magnetic grating measuring mechanism 4 detects the workpiece displacement deviation, the intelligent control module 6 immediately controls the first pair of clamping units to automatically follow and retreat until all jaws 22 are in contact with the workpiece contour, completing the centering and initial clamping.

[0045] Dual-modal detection: During the clamping process, the magnetic head 42 of the magnetic grating measuring mechanism 4 senses the magnetic grating ruler 41 on the base claw 21 in real time, collects the radial displacement data of the base claw 21 (i.e. the clamping displacement of the claw 22), and transmits the displacement data to the intelligent control module 6; at the same time, the micro force sensor array 51 on the clamping surface of the claw 22 synchronously collects the local pressure data of multiple contact points and transmits the pressure data to the intelligent control module 6, realizing dual-modal synchronous detection of displacement and force.

[0046] Intelligent analysis and closed-loop control: After receiving displacement and pressure data, the intelligent control module 6 compares and analyzes them in real time with the preset parameters in the workpiece digital twin database to determine whether the clamping state is normal. If the pressure data is detected to be outside the preset range (too tight or too loose), or the displacement data does not match the preset model (positioning deviation), the intelligent control module 6 immediately sends an adjustment command to the servo motor to adjust the speed and direction of the servo motor, thereby driving the central shaft 31 and drive ring 32 to rotate. The sliding displacement and speed of the base jaw 21 are adjusted through the decoupled drive component 33, thereby adjusting the clamping force and clamping position of the jaw 22 until the displacement and pressure data meet the preset parameters, forming a closed-loop control of "detection-analysis-adjustment" to ensure the accuracy and stability of clamping.

[0047] Reset and pick-up: After the workpiece is processed, the intelligent control module 6 sends a reverse command to the servo motor to control the servo motor to rotate in the reverse direction, which drives the drive ring 32 to rotate in the reverse direction. The decoupled drive assembly 33 drives the base jaw 21 to move radially backward. At the same time, the reset spring 81 of the reset spring mechanism 8 provides a reset force to the sliding block 331, which helps the base jaw 21 and the chuck 22 to quickly reset, release the workpiece, and complete the pick-up process. After the pick-up is completed, the fixture returns to its initial state and waits for the next clamping operation.

[0048] Throughout the entire operation, the non-contact design of the magnetic grating measuring mechanism 4 ensures the accuracy and stability of displacement measurement, the force sensor array 51 enables comprehensive detection of pressure distribution, and the closed-loop control of the intelligent control module 6 automates and intelligentizes the clamping process without manual intervention, effectively improving clamping accuracy and work efficiency, and avoiding workpiece damage.

[0049] Supplementary Explanation

[0050] In this invention, in addition to servo motors, external actuators can also be stepper motors or other drive components that can precisely control speed and direction; the number of sensors in the miniature force sensor array 51 can be adjusted to 2-8 (e.g., 4 in the embodiment) according to the size of the chuck and the clamping accuracy requirements; the magnetic pole pitch of the magnetic scale 41 can be selected to be less than 0.5mm according to the accuracy requirements; the resolution of the magnetic head 42 can be optimized according to actual needs, without affecting the implementation of this invention.

[0051] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that modifications and equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications and substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A magnetic grating force-sensing dual-mode intelligent clamping fixture, comprising a base body (1), multiple clamping units (2) arranged circumferentially thereon, a drive mechanism (3), a magnetic grating measurement mechanism (4), a force-sensing detection mechanism (5), and an intelligent control module (6), characterized in that, The clamping unit (2) includes a base claw (21) and a chuck (22) mounted on the base claw (21). The base claw (21) is slidably disposed in the base body (1) and is drivenly connected to the drive mechanism (3). The magnetic grating measuring mechanism (4) includes a magnetic grating ruler (41) and a magnetic head (42). The magnetic grating ruler (41) is embedded in the base claw (21) along the movement direction of the base claw (21). The magnetic head (42) is installed on the base body (1) and corresponds to the position of the magnetic grating ruler (41). The force sensing mechanism (5) is embedded in the clamping surface of the claw (22), and the intelligent control module (6) is installed on the base body (1) and located next to the magnetic head (42). The intelligent control module (6) is electrically connected to the magnetic head (42) and the force sensing mechanism (5) respectively.

2. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 1, characterized in that, The base claw (21) has a magnetic grating groove (211) on its radial side. The magnetic grating ruler (41) is fixedly installed in the magnetic grating groove (211). The base body (1) has a base claw groove (11) and a magnetic head through groove (12) that match the base claw (21) along the circumferential direction on its top. The inner side of the magnetic head through groove (12) corresponds to the base claw groove (11). The magnetic head (42) is installed in the magnetic head through groove (12). The magnetic head (42) is set on the same side as the magnetic grating ruler (41) and maintains a non-contact sensing gap.

3. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 2, characterized in that, The base body (1) is also provided with a card slot (13) located outside the magnetic head through slot (12). A card block (7) is installed in the card slot (13). A control chamber (71) is provided inside the card block (7). The intelligent control module (6) is encapsulated in the control chamber (71).

4. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 1, characterized in that, The force sensing mechanism (5) is a miniature force sensor array (51). The miniature force sensor array (51) is uniformly embedded in the clamping surface of the claw (22) and can simultaneously collect local pressure data of multiple contact points. The force sensing mechanism (5) and the magnetic grating measurement mechanism (4) form a dual-modal feedback, which is used by the intelligent control module (6) to make a comprehensive judgment on the clamping state.

5. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 4, characterized in that, The intelligent control module (6) has a built-in workpiece digital twin database, which is used to receive displacement data fed back by the magnetic head (42) and pressure data fed back by the micro force sensor array (51), and compare and analyze it with the workpiece digital twin model in real time. When abnormal clamping pressure or displacement is detected, the intelligent control module (6) sends a command to the drive mechanism (3) to dynamically adjust the motion parameters of the clamping unit (2) to form a closed-loop control.

6. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 1, characterized in that, The clamping unit (2) consists of four groups, arranged in pairs. Each group of clamping units (2) has a corresponding magnetic grating measuring mechanism (4) on its base jaw (21). The four groups of clamping units (2) are divided into a first pair of clamping units and a second pair of clamping units. The intelligent control module (6) is used to control the four groups of clamping units (2) to center in a preset order: first, control the first pair of clamping units to contact the workpiece for centering, and then control the second pair of clamping units to center. During the centering process of the second pair of clamping units, if the workpiece position needs to be adjusted, the intelligent control module (6) controls the first pair of clamping units to automatically follow and retreat until all jaws (22) fit the outline of the workpiece.

7. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 1, characterized in that, The drive mechanism (3) includes a central shaft (31), a drive ring (32), a decoupled drive assembly (33), and an external actuator. The central shaft (31) is rotatably supported at the center of the base body (1). The external actuator is installed on the outside of the base body (1), electrically connected to the intelligent control module (6), and drivenly connected to the central shaft (31). The drive ring (32) is sleeved on the central shaft (31) and rotates synchronously with the central shaft (31). The decoupled drive assembly (33) connects the drive ring (32) and the clamping unit (2) to convert the rotational motion of the drive ring (32) into the radial motion of the clamping unit (2). The intelligent control module (6) drives the central shaft (31) to rotate by controlling the external actuator, thereby driving the drive ring (32) to rotate, and realizing the dynamic adjustment of the motion parameters of the clamping unit (2).

8. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 7, characterized in that, The decoupled drive assembly (33) includes at least two sets of sliding blocks (331), each set of sliding blocks (331) includes at least one sliding block (331), the sliding blocks (331) are connected to the base claw (21) in a transmission manner, wherein the first set of sliding blocks and the second set of sliding blocks have opposite oblique angles; The intelligent control module (6) dynamically adjusts the motion parameters of the clamping unit (2) by controlling the rotation angle and direction of the drive ring (32).

9. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 8, characterized in that, It also includes a reset spring mechanism (8), which includes multiple reset springs (81) respectively disposed on both sides of each sliding block (331) to provide a reset force to the sliding block (331).

10. The magnetic grating force-sensing dual-mode intelligent clamping fixture according to claim 1, characterized in that, The magnetic scale (41) is a high-precision magnetic scale with a magnetic pole pitch of less than 0.5 mm. The magnetic head (42) has a resolution of micrometer level. The intelligent control module (6) is equipped with a signal processing circuit and uses interpolation subdivision technology to improve the measurement accuracy to submicrometer level.

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