Ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system

Abstract

This invention discloses a multi-directional force fusion sensing system for an ultrasonic drilling three-jaw chuck. The three-jaw chuck has a first base jaw slide, a second base jaw slide, and a third base jaw slide evenly distributed along its circumference. A clamping force monitoring module is detachably mounted on the first base jaw slide, an axial feed force monitoring module is detachably mounted on the second base jaw slide, and a cutting torque monitoring module is detachably mounted on the third base jaw slide. When clamping the workpiece, the workpiece clamping surface abuts against the clamping force monitoring module, the axial feed force monitoring module, and the cutting torque monitoring module. By having the three monitoring modules directly abut against the workpiece clamping surface and bottom end while the workpiece is clamped, the sensor placement is moved forward to near the machining deformation zone, shortening the force signal transmission path, avoiding high-frequency noise pollution from ultrasonic vibration on the sensor signal, improving the signal-to-noise ratio and anti-interference capability of the monitoring system, and solving the problems of low measurement accuracy and high false alarm rate caused by the long signal path and the distance of sensors from the machining area in traditional monitoring methods.

Description

Technical Field

[0001] This invention relates to a multi-directional force fusion sensing system for an ultrasonic drilling three-jaw chuck, belonging to the field of drilling measurement and control technology. Background Technology

[0002] In the field of mechanical parts machining, especially in deep hole drilling, the long-standing technical challenge of long chips entangled in the tool, leading to poor chip removal and even tool breakage, has persisted. To improve this situation, ultrasonic vibration-assisted machining methods have been gradually introduced into existing technologies. By applying high-frequency ultrasonic vibration to the tool or workpiece during drilling, the discontinuous cutting effect generated by the vibration can effectively interrupt the continuous formation of chips, forming smaller broken chips, thereby improving chip removal conditions, reducing cutting heat accumulation, and extending tool life. However, although ultrasonic-assisted technology improves machining conditions to some extent, the deep hole drilling process itself is enclosed, making it difficult to directly observe the interaction area between the tool and the workpiece, and difficult to obtain the machining status in real time. At the same time, the ultrasonic vibration source itself generates strong mechanical noise and acoustic interference. This interference signal can propagate through the machine tool structure, workpiece, and cutting fluid, contaminating the sensor signals in traditional monitoring schemes, resulting in a significant decrease in the signal-to-noise ratio of the monitoring system, an increase in the false alarm rate, and difficulty in accurately judging tool wear, breakage, or machining abnormalities. Traditional machining condition monitoring methods typically rely on placing multiple independent sensors, such as accelerometers and force gauges, at different locations on the machine tool spindle, tool post, or worktable, and then using complex external signal conditioning circuits for data acquisition and fusion. This approach not only requires cumbersome wiring and calibration, but the sensors are often installed far from the actual machining deformation zone, resulting in a long force signal transmission path that is susceptible to interference from various noise sources along the path. Consequently, the measurement results are not accurate enough to truly reflect the transient mechanical changes in the cutting area. Furthermore, because the high-frequency components of ultrasonic vibration overlap with the cutting force signal frequency band, traditional filtering methods struggle to effectively separate them, further exacerbating the monitoring uncertainty. Summary of the Invention

[0003] Purpose of the invention: To address the shortcomings of existing technologies, this invention provides a multi-directional force fusion sensing system for ultrasonic drilling using a three-jaw chuck. This invention achieves multi-directional force fusion sensing in ultrasonic drilling by integrating force monitoring modules in three directions onto the three-jaw chuck.

[0004] Technical Solution: A multi-directional force fusion sensing system for an ultrasonic drilling three-jaw chuck includes a three-jaw chuck with a first base jaw slide, a second base jaw slide, and a third base jaw slide evenly distributed along the circumference of the chuck. Each base jaw slide is detachably connected to a movable seat below it, and the movable seat is installed in a groove of the three-jaw chuck. A clamping force monitoring module is detachably installed on the first base jaw slide, an axial feed force monitoring module is detachably installed on the second base jaw slide, and a cutting torque monitoring module is detachably installed on the third base jaw slide. When clamping a workpiece, the workpiece clamping surface abuts against the clamping force monitoring module, the axial feed force monitoring module, and the cutting torque monitoring module. The system also includes a signal processing module, which is connected to the clamping force monitoring module, the axial feed force monitoring module, and the cutting torque monitoring module respectively.

[0005] This invention utilizes three base jaw slides evenly distributed circumferentially on a three-jaw chuck, each with a detachable clamping force monitoring module, an axial feed force monitoring module, and a cutting torque monitoring module. This allows the three monitoring modules to directly contact the workpiece clamping surface while it is being clamped. Simultaneously, a signal processing module fuses the signals from the three modules, enabling in-situ, synchronous acquisition and real-time analysis of the three key force signals—clamping force, axial feed force, and cutting torque—during ultrasonic drilling. This solves the technical challenges of traditional monitoring methods in ultrasonic drilling, such as low signal-to-noise ratio and high false alarm rate due to the enclosed machining area, strong mechanical noise and acoustic interference from the ultrasonic vibration source, and inaccurate measurement results caused by sensors being installed far from the machining deformation zone, long signal transmission paths, and inaccurate measurement results. Each base jaw slide is detachably connected to its underlying movable seat via mounting bolts.

[0006] In a preferred embodiment, in order to achieve stable and static monitoring of the clamping force within a confined jaw space, while avoiding interference from high-frequency noise from ultrasonic vibration on dynamic signals, the clamping force monitoring module includes a first clamping block and a strain gauge resistor sensor. A first groove is formed along the horizontal direction on the vertical clamping surface of the first base jaw slide, and the strain gauge resistor sensor is embedded in the first groove. The first clamping block is detachably connected to the vertical clamping surface of the first base jaw slide, and the contact of the strain gauge resistor sensor is in contact with the first clamping block.

[0007] By creating a first groove along the horizontal direction on the vertical clamping surface of the first base claw slide, a strain gauge resistance sensor is embedded therein, and the first clamping block is made to directly contact the sensor contact point, thereby converting the radial displacement generated when the workpiece is clamped into the change of electrical signal of the sensor, achieving high linearity and low drift measurement of the clamping force.

[0008] In a preferred embodiment, in order to ensure the structural rigidity between the first clamping block and the first base claw slide, and to ensure that the minute displacement generated by the clamping force when the first clamping block clamps the workpiece can be effectively transmitted and acted on the strain gauge resistance sensor, a first elastic pad is installed between the vertical clamping surfaces of the first clamping block and the first base claw slide.

[0009] By installing a first elastic pad between the vertical clamping surfaces of the first clamping block and the first base claw slide, the compressible deformation characteristics of the elastic pad are utilized to maintain the overall connection's firmness and amplify the effect of minute displacement on the sensor contact, thereby achieving high sensitivity and high reliability acquisition of the clamping force signal.

[0010] In a preferred embodiment, in order to capture the dynamic and rapidly changing axial feed force signal in real time during ultrasonic drilling, the axial feed force monitoring module includes a second clamping block and a first piezoelectric sensor. A second groove is formed on the horizontal clamping surface of the second base jaw slide along the vertical direction. The first piezoelectric sensor is embedded in the second groove. The second clamping block is detachably connected to the horizontal clamping surface of the second base jaw slide. The contact of the first piezoelectric sensor is in contact with the second clamping block.

[0011] By creating a second groove along the vertical direction on the horizontal clamping surface of the second base claw slide, a first piezoelectric sensor with fast response speed and high sensitivity is embedded therein, and the second clamping block abuts against the sensor contact point, thereby directly converting the axial thrust of the workpiece into the charge output of the piezoelectric sensor, realizing transient and high-precision monitoring of the axial feed force, and effectively avoiding the high-frequency contamination range of ultrasonic vibration.

[0012] In a preferred embodiment, to avoid structural interference between the mounting bolts between the second base claw slide and the lower movable seat and the piezoelectric sensor contact, and to ensure that the second clamping block can properly press the sensor and generate a valid signal, a third groove communicating with the second groove is formed on the horizontal clamping surface of the second base claw slide along the vertical direction. The second clamping block is embedded in the third groove and contacts the first piezoelectric sensor contact in the lower second groove. The upper surface of the end of the second clamping block that contacts the first piezoelectric sensor contact is higher than the horizontal clamping surface of the corresponding second base claw slide.

[0013] By creating a third groove that communicates with the second groove along the vertical direction on the horizontal clamping surface of the second base claw slide, the second clamping block is embedded in the third groove, and the upper surface of the end that contacts the sensor contact is higher than the horizontal clamping surface of the second base claw slide. This ensures that the sensor can still obtain accurate displacement triggering even with the presence of mounting bolts, thus achieving a balance between structural avoidance and signal reliability.

[0014] In a preferred embodiment, in order to achieve dual-part coordinated sensing of the axial feed force by the second clamping block from a lateral perspective parallel to the chuck axis, and to efficiently transmit the axial force to the sensor by utilizing the combined force characteristics of the workpiece bottom end and the outer circular surface to avoid spatial interference from the mounting bolts, the projection of the second clamping block in the direction parallel to the chuck axis is Z-shaped. One end of the second clamping block is detachably connected to the second base jaw slide, and the other end is embedded in the third groove and detachably connected to the second base jaw slide. The bottom of the other end is in contact with the contact point of the first piezoelectric sensor.

[0015] By designing the projection of the second clamping block in a direction parallel to the chuck axis as a Z-shape, one end of the Z-shape is detachably connected to the second base claw slide to form a positioning constraint. Its middle section abuts against the outer circular surface of the workpiece to bear radial positioning and guidance, and its other end is embedded in the third groove and the bottom of this end contacts the first piezoelectric sensor contact point. At the same time, the bottom end of the workpiece abuts against the other end to directly transmit the axial feed force, thereby forming a force transmission path in which the bottom end of the workpiece and the outer circular surface work together to apply force, and the Z-shaped structure constrains the force transmission, thus realizing accurate and reliable measurement of the axial feed force in a confined space.

[0016] In a preferred embodiment, in order to ensure that the second clamping block can effectively transmit the minute displacement to the first piezoelectric sensor during the deformation process under stress, and at the same time maintain the connection stiffness between the second clamping block and each clamping surface of the second base claw slide, a second elastic pad is installed between the inner surface of the second clamping block and each clamping surface of the second base claw slide.

[0017] By installing a second elastic shim between the inner surface of the second clamping block and each clamping surface of the second base claw slide, the buffering and pre-tightening adjustment of the elastic shim not only avoids stress concentration or signal distortion caused by rigid contact, but also ensures the sensitivity and linearity of displacement transmission, thus achieving high-fidelity acquisition of the axial feed force signal.

[0018] In a preferred embodiment, to accurately sense the cutting torque in the tangential direction during ultrasonic drilling while avoiding interference with workpiece clamping, the cutting torque monitoring module includes a third clamping block and a second piezoelectric sensor. A fourth groove is formed on the side end face of the third base jaw slide from its top surface downwards. The second piezoelectric sensor is embedded in the fourth groove. The projection of the third clamping block on a plane perpendicular to the chuck axis is L-shaped. The inner surface of one end of the third clamping block is detachably connected to the side end face of the third base jaw slide and contacts the second piezoelectric sensor contact point. The inner surface of the other end is detachably connected to the vertical clamping surface of the third base jaw slide.

[0019] By creating a fourth groove from top to bottom on the side end face of the third base jaw slide, a second piezoelectric sensor is embedded therein. The third clamping block is designed to project an L-shape onto a plane perpendicular to the chuck axis, so that the inner surface of one end abuts against the sensor contact point on the side end face, and the inner surface of the other end abuts against the vertical clamping surface. In this way, the circumferential tangential force on the workpiece is converted into normal pressure on the sensor through the L-shaped structure, realizing dynamic and high-sensitivity monitoring of cutting torque.

[0020] In a preferred embodiment, to ensure that the third clamping block can efficiently and linearly transmit the tangential force generated by the cutting torque to the second piezoelectric sensor, and to prevent signal nonlinearity or mechanical damage caused by rigid contact between the third clamping block and the side end face and vertical clamping surface of the third base claw slide, a third elastic pad is respectively installed between the inner surface of the third clamping block and the side end face and vertical clamping surface of the third base claw slide.

[0021] By installing third elastic shims between the inner surface of the third clamping block and the side end face and vertical clamping surface of the third base claw slide, respectively, the high linearity and high repeatability of the cutting torque signal are achieved by utilizing the uniform force and micro-displacement transmission characteristics of the elastic shims.

[0022] In a preferred embodiment, in order to achieve precise control of the preload of each sensor during the assembly process, so that each sensor can operate in the calibration range closest to linearity, thereby ensuring the accuracy and consistency of the measurement results, the first base jaw slide and the clamping force monitoring module, the second base jaw slide and the axial feed force monitoring module, and the third base jaw slide and the cutting torque monitoring module are all detachably connected by preload screws.

[0023] The first base jaw slide and clamping force monitoring module, the second base jaw slide and axial feed force monitoring module, and the third base jaw slide and cutting torque monitoring module are all connected by detachable pre-tightening screws. The initial pressure state of the sensor is changed by adjusting the tightening degree of the two pre-tightening screws, which realizes convenient calibration of the sensor's working point and long-term stability maintenance.

[0024] Beneficial Effects: This invention, by evenly distributing three base jaw slides circumferentially on a three-jaw chuck and detachably mounting clamping force monitoring modules, axial feed force monitoring modules, and cutting torque monitoring modules respectively, allows the three monitoring modules to directly contact the workpiece clamping surface and bottom end while the workpiece is clamped. Simultaneously, a signal processing module performs in-situ, synchronous acquisition and fusion analysis of the three types of force signals, thereby moving the sensor placement closer to the machining deformation zone, significantly shortening the force signal transmission path, effectively avoiding high-frequency noise pollution from ultrasonic vibration on the sensor signal, improving the signal-to-noise ratio and anti-interference capability of the monitoring system, and solving the problems of low measurement accuracy and high false alarm rate caused by the long signal path and distance of sensors from the machining area in traditional monitoring methods. By embedding a strain gauge resistance sensor in the clamping force monitoring module and using a first elastic pad, static clamping is ensured. Stable and highly linear force measurement is achieved, while the amplification effect of the first elastic shim's slight displacement improves the balance between signal sensitivity and structural stiffness. By employing a Z-shaped projection second clamping block in the axial feed force monitoring module, the bottom end of the workpiece and the outer circular surface apply force collaboratively. Combined with the buffering and preload adjustment of the second elastic shim, accurate, high-fidelity transmission and linear acquisition of dynamic axial feed force are achieved within a confined space. By setting an L-shaped projection third clamping block and a third elastic shim in the cutting torque monitoring module, the circumferential tangential force of the workpiece is efficiently converted into normal pressure on the piezoelectric sensor, achieving dynamic and highly repeatable monitoring of the cutting torque. At the same time, each monitoring module is detachably connected to the base jaw slide via a preload screw, allowing independent adjustment of the preload of each sensor to ensure it always operates within the calibration range closest to linearity. This invention effectively improves the synchronous sensing accuracy and anti-interference capability of multi-dimensional force signals during ultrasonic drilling, enhances the real-time performance and reliability of deep hole machining status monitoring, and reduces the complexity of system wiring and calibration. It can meet the engineering practical requirements of intelligent monitoring and abnormal early warning of tool status in ultrasonic deep hole drilling. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0026] Figure 1 This is an overall structural diagram of the present invention; Figure 2 This is a cross-sectional view of the clamping force monitoring module of the present invention; Figure 3 This is a cross-sectional view of the axial feed force monitoring module of the present invention; Figure 4This is a cross-sectional view of the cutting torque monitoring module of the present invention. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

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

[0029] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0030] like Figures 1-4 As shown, an ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system includes a three-jaw chuck 1. A first base jaw slide 11, a second base jaw slide 12, and a third base jaw slide 13 are evenly distributed along the circumference of the three-jaw chuck 1. Each base jaw slide is detachably connected to a movable seat 2 below it. The movable seat 2 is installed in a groove 14 of the three-jaw chuck 1. A clamping force monitoring module 3 is detachably installed on the first base jaw slide 11, an axial feed force monitoring module 4 is detachably installed on the second base jaw slide 12, and a cutting torque monitoring module 5 is detachably installed on the third base jaw slide 13. When clamping a workpiece, the workpiece clamping surface abuts against the clamping force monitoring module 3, the axial feed force monitoring module 4, and the cutting torque monitoring module 5. The system also includes a signal processing module, which is signal-connected to the clamping force monitoring module 3, the axial feed force monitoring module 4, and the cutting torque monitoring module 5, respectively.

[0031] By evenly distributing three base jaw slides along the circumference of the three-jaw chuck 1, and detachably mounting the clamping force monitoring module 3, axial feed force monitoring module 4, and cutting torque monitoring module 5 respectively, the three monitoring modules directly contact the workpiece clamping surface when the workpiece is clamped. Simultaneously, the signals from the three modules are fused through a signal processing module, enabling in-situ, synchronous acquisition and real-time analysis of the three key force signals—clamping force, axial feed force, and cutting torque—during ultrasonic drilling. This solves the technical problems of low signal-to-noise ratio and high false alarm rate in traditional monitoring methods due to the enclosed machining area, strong mechanical noise and acoustic interference from the ultrasonic vibration source, as well as the inaccurate measurement results caused by the sensor installation position being far from the machining deformation zone, long signal transmission paths, and inaccurate measurement results. Each base jaw slide is detachably connected to the moving seat 2 below it via mounting bolts 7. The workpiece clamping surface includes the outer cylindrical surface and the lower end surface.

[0032] In this embodiment, the signal processing module includes a signal transmitter and two charge amplifiers. The signal transmitter is connected to the clamping force monitoring module and is used to transform and amplify the voltage signal it generates. The two charge amplifiers are respectively connected to the axial feed force monitoring module and the cutting torque monitoring module and are used to convert the charge signals they generate into voltage signals. The signal processing module also includes a signal acquisition unit and monitoring software. The signal acquisition unit receives the signals output by the signal transmitter and the charge amplifiers and transmits them to the monitoring software in real time. The monitoring software analyzes the signal characteristics to provide feedback on the tool status and identify abnormal alarms.

[0033] In order to achieve stable and static monitoring of clamping force in a narrow jaw space, while avoiding interference of high-frequency noise from ultrasonic vibration on dynamic signals, the clamping force monitoring module 3 includes a first clamping block 31 and a strain gauge resistance sensor 32. A first groove 111 is formed on the vertical clamping surface of the first base jaw slide 11 along the horizontal direction. The strain gauge resistance sensor 32 is embedded in the first groove 111. The first clamping block 31 is detachably connected to the vertical clamping surface of the first base jaw slide 11. The contact of the strain gauge resistance sensor 32 is in contact with the first clamping block 31.

[0034] By creating a first groove 111 along the horizontal direction on the vertical clamping surface of the first base jaw slide 11, a strain gauge resistance sensor 32 is embedded therein, and the first clamping block 31 is in direct contact with the sensor contact point. This converts the radial displacement generated when the workpiece is clamped into a change in the sensor's electrical signal, achieving high linearity and low drift measurement of the clamping force. The first clamping block 31 abuts against the outer cylindrical surface of the workpiece.

[0035] In order to ensure the structural rigidity between the first clamping block 31 and the first base claw slide 11, and to ensure that the slight displacement generated by the clamping force when the first clamping block 31 clamps the workpiece can be effectively transmitted and act on the strain resistance sensor 32, a first elastic pad 33 is installed between the vertical clamping surfaces of the first clamping block 31 and the first base claw slide 11.

[0036] By installing a first elastic pad 33 between the vertical clamping surfaces of the first clamping block 31 and the first base claw slide 11, the compressible deformation characteristics of the elastic pad are utilized to maintain the overall connection's firmness and amplify the effect of minute displacement on the sensor contact, thereby achieving high sensitivity and high reliability acquisition of the clamping force signal.

[0037] In order to capture the dynamic and rapidly changing axial feed force signal in real time during ultrasonic drilling, the axial feed force monitoring module 4 includes a second clamping block 41 and a first piezoelectric sensor 42. A second groove 121 is formed on the horizontal clamping surface of the second base jaw slide 12 along the vertical direction. The first piezoelectric sensor 42 is embedded in the second groove 121. The second clamping block 41 is detachably connected to the horizontal clamping surface of the second base jaw slide 12. The contact of the first piezoelectric sensor 42 is in contact with the second clamping block 41.

[0038] By opening a second groove 121 in the vertical direction on the horizontal clamping surface of the second base claw slide 12, a first piezoelectric sensor 42 with fast response speed and high sensitivity is embedded therein, and the second clamping block 41 abuts against the sensor contact point, thereby directly converting the axial thrust of the workpiece into the charge output of the piezoelectric sensor, realizing transient and high-precision monitoring of the axial feed force, and effectively avoiding the high-frequency contamination range of ultrasonic vibration.

[0039] To avoid structural interference between the mounting bolts 7 between the second base claw slide 12 and the lower movable seat 2 and the piezoelectric sensor contact, and to ensure that the second clamping block 41 can properly press the sensor and generate a valid signal, a third groove 122 communicating with the second groove 121 is provided on the horizontal clamping surface of the second base claw slide 12 in the vertical direction. The second clamping block 41 is embedded in the third groove 122 and contacts the first piezoelectric sensor 42 contact in the lower second groove 121. The upper surface of the end of the second clamping block 41 that contacts the first piezoelectric sensor 42 contact is higher than the horizontal clamping surface of the corresponding second base claw slide 12.

[0040] By opening a third groove 122 in the vertical direction on the horizontal clamping surface of the second base claw slide 12, which communicates with the second groove 121, the second clamping block 41 is embedded in the third groove 122, and the upper surface of the end that contacts the sensor contact is higher than the horizontal clamping surface of the second base claw slide 12. Thus, even with the presence of the mounting bolt 7, the sensor can still obtain accurate displacement triggering, achieving a balance between structural avoidance and signal reliability.

[0041] In order to achieve dual-part coordinated sensing of axial feed force by the second clamping block 41 from a side view parallel to the chuck axis, and to efficiently transmit the axial force to the sensor by utilizing the combined force characteristics of the workpiece bottom end and outer circular surface to avoid spatial interference of the mounting bolt 7, the projection of the second clamping block 41 in the direction parallel to the chuck axis is Z-shaped. One end of the second clamping block 41 is detachably connected to the second base jaw slide 12, and the other end is embedded in the third groove 122 and detachably connected to the second base jaw slide 12. The bottom of the other end is in contact with the contact point of the first piezoelectric sensor 42.

[0042] By designing the projection of the second clamping block 41 in a direction parallel to the chuck axis as a Z-shape, one end of the Z-shape is detachably connected to the second base jaw slide 12 to form a positioning constraint. Its middle section abuts against the outer surface of the workpiece to bear radial positioning and guidance, while its other end is embedded in the third groove 122, with its bottom contacting the first piezoelectric sensor 42. Simultaneously, the bottom end of the workpiece abuts against this other end to directly transmit the axial feed force. This forms a force transmission path where the bottom end of the workpiece and the outer surface exert force collaboratively, and the Z-shaped structure constrains the force transmission, achieving accurate and reliable measurement of the axial feed force within a confined space. The outer surface and lower end face of the workpiece simultaneously abut against the second clamping block 41.

[0043] In order to ensure that the second clamping block 41 can effectively transmit the minute displacement to the first piezoelectric sensor 42 during the deformation process under force, and at the same time maintain the connection stiffness between the second clamping block 41 and each clamping surface of the second base claw slide 12, a second elastic pad 43 is installed between the inner surface of the second clamping block 41 and each clamping surface of the second base claw slide 12.

[0044] By installing a second elastic pad 43 between the inner surface of the second clamping block 41 and each clamping surface of the second base claw slide 12, the buffering and pre-tightening adjustment of the elastic pad avoids stress concentration or signal distortion caused by rigid contact, and ensures the sensitivity and linearity of displacement transmission, thus achieving high-fidelity acquisition of axial feed force signal.

[0045] To accurately sense the cutting torque in the tangential direction during ultrasonic drilling and avoid interference with workpiece clamping, the cutting torque monitoring module 5 includes a third clamping block 51 and a second piezoelectric sensor 52. A fourth groove 131 is formed on the side end face of the third base jaw slide 13 from its top surface downwards. The second piezoelectric sensor 52 is embedded in the fourth groove 131. The projection of the third clamping block 51 on the plane perpendicular to the chuck axis is L-shaped. The inner surface of one end of the third clamping block 51 is detachably connected to the side end face of the third base jaw slide 13 and contacts the second piezoelectric sensor 52. The inner surface of the other end is detachably connected to the vertical clamping surface of the third base jaw slide 13.

[0046] A fourth groove 131 is formed from top to bottom on the side end face of the third base jaw slide 13, in which the second piezoelectric sensor 52 is embedded. The third clamping block 51 is designed to project into an L-shape on a plane perpendicular to the chuck axis, with one end of its inner surface abutting against the sensor contact on the side end face, and the other end of its inner surface abutting against the vertical clamping surface. This converts the circumferential tangential force on the workpiece into normal pressure on the sensor through the L-shaped structure, achieving dynamic and high-sensitivity monitoring of the cutting torque. The outer cylindrical surface of the workpiece abuts against the third clamping block 51.

[0047] In order to ensure that the third clamping block 51 can efficiently and linearly transmit the tangential force generated by the cutting torque to the second piezoelectric sensor 52, and at the same time prevent signal nonlinearity or mechanical damage caused by rigid contact between the third clamping block 51 and the side end face and vertical clamping surface of the third base claw slide 13, a third elastic pad 53 is installed between the inner surface of the third clamping block 51 and the side end face and vertical clamping surface of the third base claw slide 13, respectively.

[0048] By installing third elastic pads 53 between the inner surface of the third clamping block 51 and the side end face and vertical clamping surface of the third base claw slide 13, the high linearity and high repeatability of the cutting torque signal are achieved by utilizing the uniform force and micro displacement transmission characteristics of the elastic pads.

[0049] In order to achieve precise control of the preload of each sensor during the assembly process, so that each sensor can work in the calibration range closest to linearity, thereby ensuring the accuracy and consistency of the measurement results, the first base jaw slide 11 and the clamping force monitoring module 3, the second base jaw slide 12 and the axial feed force monitoring module 4, and the third base jaw slide 13 and the cutting torque monitoring module 5 are all detachably connected by preload screws 6.

[0050] The first base jaw slide 11 is connected to the clamping force monitoring module 3, the second base jaw slide 12 is connected to the axial feed force monitoring module 4, and the third base jaw slide 13 is connected to the cutting torque monitoring module 5 by pre-tightening screws 6. The initial pressure state of the sensor is changed by adjusting the tightening degree of the two pre-tightening screws 6, which realizes convenient calibration of the sensor's working point and long-term stability maintenance.

[0051] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0052] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A multi-directional force fusion sensing system for an ultrasonic drilling three-jaw chuck, characterized in that: The chuck includes a three-jaw chuck (1), on which a first base jaw slide (11), a second base jaw slide (12), and a third base jaw slide (13) are evenly distributed along the circumference. Each base jaw slide is detachably connected to a movable seat (2) below it. The movable seat (2) is installed in a groove (14) of the three-jaw chuck (1). A clamping force monitoring module (3) is detachably installed on the first base jaw slide (11), an axial feed force monitoring module (4) is detachably installed on the second base jaw slide (12), and a cutting torque monitoring module (5) is detachably installed on the third base jaw slide (13). When clamping a workpiece, the workpiece clamping surface abuts against the clamping force monitoring module (3), the axial feed force monitoring module (4), and the cutting torque monitoring module (5). The chuck also includes a signal processing module, which is connected to the clamping force monitoring module (3), the axial feed force monitoring module (4), and the cutting torque monitoring module (5) respectively.

2. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 1, characterized in that: The clamping force monitoring module (3) includes a first clamping block (31) and a strain gauge resistance sensor (32). A first groove (111) is provided on the vertical clamping surface of the first base claw slide (11) in the horizontal direction. The strain gauge resistance sensor (32) is embedded in the first groove (111). The first clamping block (31) is detachably connected to the vertical clamping surface of the first base claw slide (11). The contact of the strain gauge resistance sensor (32) is in contact with the first clamping block (31).

3. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 2, characterized in that: A first elastic pad (33) is installed between the first clamping block (31) and the vertical clamping surface of the first base claw slide (11).

4. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 1, characterized in that: The axial feed force monitoring module (4) includes a second clamping block (41) and a first piezoelectric sensor (42). A second groove (121) is provided on the horizontal clamping surface of the second base claw slide (12) along the vertical direction. The first piezoelectric sensor (42) is embedded in the second groove (121). The second clamping block (41) is detachably connected to the horizontal clamping surface of the second base claw slide (12). The contact of the first piezoelectric sensor (42) is in contact with the second clamping block (41).

5. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 4, characterized in that: The second base claw slide (12) has a third groove (122) that communicates with the second groove (121) along the vertical direction on the horizontal clamping surface. The second clamping block (41) is embedded in the third groove (122) and contacts the first piezoelectric sensor (42) in the lower second groove (121). The upper surface of the second clamping block (41) that contacts the first piezoelectric sensor (42) is higher than the horizontal clamping surface of the corresponding second base claw slide (12).

6. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 5, characterized in that: The projection of the second clamping block (41) in the direction parallel to the chuck axis is Z-shaped. One end of the second clamping block (41) is detachably connected to the second base claw slide (12), the other end is embedded in the third groove (122) and detachably connected to the second base claw slide (12), and the bottom of the other end is in contact with the contact point of the first piezoelectric sensor (42).

7. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 6, characterized in that: A second elastic pad (43) is installed between the inner surface of the second clamping block (41) and each clamping surface of the second base claw slide (12).

8. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 1, characterized in that: The cutting torque monitoring module (5) includes a third clamping block (51) and a second piezoelectric sensor (52). A fourth groove (131) is provided on the side end face of the third base jaw slide (13) from its top surface downwards. The second piezoelectric sensor (52) is embedded in the fourth groove (131). The projection of the third clamping block (51) on the plane perpendicular to the chuck axis is L-shaped. The inner surface of one end of the third clamping block (51) is detachably connected to the side end face of the third base jaw slide (13) and contacts the second piezoelectric sensor (52). The inner surface of the other end is detachably connected to the vertical clamping surface of the third base jaw slide (13).

9. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 8, characterized in that: A third elastic pad (53) is installed between the inner surface of the third clamping block (51) and the side end face and vertical clamping surface of the third base claw slide (13).

10. The ultrasonic drilling three-jaw chuck multi-directional force fusion sensing system according to claim 1, characterized in that: The first base jaw slide (11) and the clamping force monitoring module (3), the second base jaw slide (12) and the axial feed force monitoring module (4), and the third base jaw slide (13) and the cutting torque monitoring module (5) are all detachably connected by preload screws (6).

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