Sensing-actuating integrated longitudinal-bending composite ultrasonic drilling knife handle

Abstract

The invention discloses a sensing actuation integrated type longitudinal bending composite ultrasonic drilling cutter handle, and belongs to the technical field of ultrasonic auxiliary machining. The problems that a traditional ultrasonic drilling cutter handle amplitude measurement external sensor is difficult to arrange, and amplitude sensing based on electrical parameter feedback is prone to being interfered by internal electric signals of a power source, so that the amplitude sensing precision is low are solved. The sensing actuation integrated longitudinal bending composite ultrasonic drilling cutter handle comprises a rear end cover 1, a sensing actuation piezoelectric ceramic group 2, an insulating layer 3, a thermal expansion cutter handle 4 and a drilling and milling cutter 5. Longitudinal vibration and bending vibration sensing ceramics are innovatively implanted into the cutter body, so that precise in-situ sensing of ultrasonic amplitudes of longitudinal vibration and bending vibration can be realized; meanwhile, by applying longitudinal vibration and bending vibration excitation signals, simultaneous excitation of a longitudinal vibration mode and a bending vibration mode can be achieved, so that the drilling and milling tool nose outputs an elliptical track, and the longitudinal bending ultrasonic drilling tool handle can achieve the axial ironing and impact machining effect and the intermittent cutting effect in the cutting direction at the same time in the drilling process; and the drilling precision and the processing performance of difficult-to-process materials are improved. According to the design, integration of sensing and actuating functions of the cutter handle is ingeniously achieved, the structure of the cutter handle is simplified, the machining precision is improved, and the application scene is expanded.

Description

Technical Field

[0001] The invention belongs to the technical field of ultrasonic assisted machining, and in particular relates to a sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool holder. Background Art

[0002] Ultrasonic assisted machining technology is a special machining technology for difficult-to-machine materials. It provides important support for the development of advanced manufacturing due to its many advantages, such as reduced cutting force, lower cutting temperature, reduced tool wear, easy chip removal, and improved precision. Since the longitudinal-bending mode composite ultrasonic drilling toolholder can easily produce an elliptical trajectory in the drilling direction and cutting direction, it is very suitable for drilling brittle and hard difficult-to-machine materials and composite materials. As a core component, the constant frequency and precise amplitude control of the ultrasonic drilling toolholder directly affect the machining accuracy and stability of the tool. However, since the amplitude sensing of traditional ultrasonic drilling toolholders mostly uses the internal electrical parameter feedback of the power supply, the signal feedback is delayed and is easily interfered by the internal electrical signal of the power supply, resulting in low amplitude sensing accuracy and contact between the drill bit and the workpiece during the drilling process. It is difficult to arrange external sensors, which limits the improvement of ultrasonic assisted drilling accuracy, processing stability and application expansion.

[0003] The sensor-actuated integrated longitudinal-bending composite ultrasonic drilling toolholder implants longitudinal and bending vibration sensing ceramics into the drilling toolholder, realizing precise in-situ sensing of the longitudinal and bending vibration ultrasonic amplitudes, improving the sensing accuracy and simplifying the sensor arrangement, and real-time amplitude precision sensing can still be achieved during the contact process between the drill bit and the workpiece; at the same time, the integrated design of the sensor and the actuator simplifies the structure of the longitudinal-bending composite ultrasonic drilling toolholder, which is of great significance to promoting the integrated development of ultrasonic-assisted machining tools and their application in the field of high-precision drilling of difficult-to-process materials. Summary of the invention

[0004] In order to solve the problems in the prior art that the power supply electrical parameter feedback is easily interfered by the power supply signal, resulting in low sensing accuracy, and the external sensor is difficult to arrange during the machining process due to the contact restriction between the tool and the workpiece, the present invention proposes a sensor-actuated integrated longitudinal and bending composite ultrasonic drilling tool holder in which sensor ceramics are embedded inside the ultrasonic drilling tool body, which can realize precise in-situ sensing of the amplitude during the ultrasonic drilling tool machining process, simplify the sensor arrangement, and simplify the tool structure.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool holder, comprising the following steps:

[0006] A sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool handle, characterized in that: the sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool handle comprises a rear end cover (1), a sensor-actuated piezoelectric ceramic group (2), an insulating layer (3), a thermal expansion tool handle (4), and a drilling and milling tool (5); the sensor-actuated piezoelectric ceramic group (2) comprises a group of bending vibration sensing piezoelectric ceramics PZT-BS (2-1), a group of bending vibration actuating piezoelectric ceramics PZT-BA (2-2), a group of longitudinal ...BA (2-2), a group of longitudinal vibration sensing piezoelectric ceramics PZT-BS (2-1 A piezoelectric ceramic PZT-LS (2-3), a group of longitudinal vibration actuated piezoelectric ceramics PZT-LA (2-4), four groups of piezoelectric ceramics are sleeved outside the insulating layer (3) and pressed onto a thermal expansion tool holder (4) through a rear end cover (1); the rear end cover (1) is fixed to the thermal expansion tool holder (4) through a thread on the rear end cover (1) that matches the thermal expansion tool holder (4); the thermal expansion tool holder (4) clamps the drilling and milling tool (5) by using the difference in thermal expansion coefficient between the tool holder and the tool.

[0007] Furthermore, the longitudinal vibration sensing piezoelectric ceramic PZT-LS (2-3) implanted in the tool body senses the vibration of the tool along the axial direction, and the real-time longitudinal vibration amplitude of the tool during the machining process is obtained by processing the sensing signal; the bending vibration sensing piezoelectric ceramic PZT-BS (2-1) implanted in the tool body senses the vibration of the tool in the bending vibration direction, and the in-situ sensing of the real-time bending vibration amplitude of the tool during the machining process is achieved by processing the bending vibration sensing signal; the sensing actuation piezoelectric ceramic group (2) and the rear end cover (1) are electrically isolated by the insulating layer (3), so as to prevent the piezoelectric ceramic electrical signal from short-circuiting and ensure the stable operation of the piezoelectric ceramic.

[0008] Furthermore, by applying two AC signals (signal A and signal B) with the same frequency and different phases to the bending vibration actuated piezoelectric ceramic PZT-BA (2-2) and the longitudinal vibration actuated piezoelectric ceramic PZT-LA (2-4), the elliptical motion of the tool tip within the period T can be obtained. The longitudinal vibration is used to achieve the axial ironing effect of the tool, while the bending vibration is used to achieve the intermittent cutting effect of the side edge. The longitudinal vibration and the bending vibration are spatially orthogonal to each other under the application of the phase difference Φ = 90°, ensuring that the intermittent cutting and the ironing effect can be achieved simultaneously within one period. By changing the phase angle Φ between the signal A and the signal B, the elliptical trajectory can be adjusted to achieve the intensity adjustment of the ironing effect and the intermittent cutting effect.

[0009] Due to the adoption of the above technical solution, the present invention has the following advantages and beneficial effects compared with the prior art:

[0010] 1. Longitudinal vibration sensing ceramics and bending vibration sensing ceramics are embedded in the tool body to achieve precise in-situ sensing of the longitudinal vibration and bending vibration amplitudes, simplifying the arrangement of external sensors of the tool amplitude control system. At the same time, the configuration of the tool body implanted with piezoelectric sensing ceramics avoids the interference of the internal electrical parameters of the power supply in the amplitude sensing of the power supply electrical parameter feedback, thereby improving the amplitude sensing accuracy and stability of the cutting process. It has broad application prospects in precision drilling and precision milling of difficult-to-process materials and composite materials.

[0011] 2. The elliptical trajectory output of the drilling and milling tool tip is realized by combining longitudinal vibration and bending vibration. Longitudinal vibration realizes the ironing and impact processing effects along the axial direction, reduces the axial force, and helps to improve the burrs at the exit of composite material drilling. Bending vibration realizes the intermittent cutting effect of the tool and the workpiece, reduces the cutting force of the drilling and milling tools, and reduces tool wear. At the same time, high-frequency two-dimensional ultrasonic vibration helps to discharge chips and improve processing accuracy. By combining longitudinal vibration and bending vibration, the longitudinal bending ultrasonic drilling tool holder can simultaneously realize the axial ironing and impact processing effects and the intermittent cutting effect in the cutting direction during the drilling process, improve the drilling accuracy and the processing performance of difficult-to-process materials, reduce tool wear and increase tool life, and improve the economic benefits of difficult-to-process materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a cross-sectional view of the main view of the present invention;

[0013] Figure 2 It is an isometric view of the present invention.

[0014] Figure 3 This is an excitation signal diagram of the present invention. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0016] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0017] like Figure 1As shown, a sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool handle is characterized in that: the sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool handle comprises a rear end cover (1), a sensor-actuated piezoelectric ceramic group (2), an insulating layer (3), a thermal expansion tool handle (4), and a drilling and milling tool (5); the sensor-actuated piezoelectric ceramic group (2) comprises a group of bending vibration sensing piezoelectric ceramics PZT-BS (2-1), a group of bending vibration actuating piezoelectric ceramics PZT-BA (2-2), a group of longitudinal The invention discloses a vibration sensing piezoelectric ceramic PZT-LS (2-3), a group of longitudinal vibration actuating piezoelectric ceramic PZT-LA (2-4), and four groups of piezoelectric ceramics are sleeved on the outside of the insulating layer (3) and pressed onto the thermal expansion tool holder (4) through the rear end cover (1); the rear end cover (1) is fixed to the thermal expansion tool holder (4) through the threads on the rear end cover (1) that match the thermal expansion tool holder (4); the thermal expansion tool holder (4) clamps the drilling and milling tool (5) by using the difference in thermal expansion coefficients between the tool holder and the tool.

[0018] The longitudinal vibration sensing piezoelectric ceramic PZT-LS (2-3) implanted in the tool body senses the vibration of the tool along the axial direction, and the real-time longitudinal vibration amplitude of the tool during the machining process is obtained by processing the sensing signal; the bending vibration sensing piezoelectric ceramic PZT-BS (2-1) implanted in the tool body senses the vibration of the tool in the bending vibration direction, and the in-situ sensing of the real-time bending vibration amplitude of the tool during the machining process is achieved by processing the bending vibration sensing signal; the sensing actuation piezoelectric ceramic group (2) and the rear end cover (1) are electrically isolated by the insulating layer (3), so as to prevent the piezoelectric ceramic electrical signal from short-circuiting and ensure the stable operation of the piezoelectric ceramic.

[0019] By applying two AC signals (signal A and signal B) with the same frequency but different phases to the bending vibration actuated piezoelectric ceramic PZT-BA (2-2) and the longitudinal vibration actuated piezoelectric ceramic PZT-LA (2-4), the elliptical motion of the tool tip within a period T can be obtained. The longitudinal vibration is used to achieve the axial ironing effect of the tool, while the bending vibration is used to achieve the intermittent cutting effect of the side edge. The longitudinal vibration and the bending vibration are spatially orthogonal to each other under the applied phase difference Φ = 90°, ensuring that the intermittent cutting and ironing effects can be achieved simultaneously within one cycle. By changing the phase angle Φ between signal A and signal B, the elliptical trajectory can be adjusted to achieve the intensity adjustment of the ironing effect and the intermittent cutting effect.

[0020] It should be noted that, in the present invention, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0021] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be 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 present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features applied herein.

Claims

1. A sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool holder, characterized in that: The sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool holder comprises a rear end cover (1), a sensor-actuated piezoelectric ceramic group (2), an insulating layer (3), a thermal expansion tool holder (4), and a drilling and milling tool (5); the sensor-actuated piezoelectric ceramic group (2) comprises a group of bending vibration sensing piezoelectric ceramics PZT-BS (2-1), a group of bending vibration actuating piezoelectric ceramics PZT-BA (2-2), a group of longitudinal vibration sensing piezoelectric ceramics PZT-LS (2-3), and a group of longitudinal vibration actuating piezoelectric ceramics PZT-LA (2-4); the four groups of piezoelectric ceramics are sleeved on the outside of the insulating layer (3) and pressed onto the thermal expansion tool holder (4) through the rear end cover (1); the rear end cover (1) is fixed to the thermal expansion tool holder (4) through a thread on the rear end cover (1) that matches the thermal expansion tool holder (4); the thermal expansion tool holder (4) clamps the drilling and milling tool (5) by utilizing the difference in thermal expansion coefficients between the tool holder and the tool.

2. A sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool handle according to claim 1, characterized in that: The longitudinal vibration sensing piezoelectric ceramic PZT-LS (2-3) implanted in the tool body senses the vibration of the tool along the axial direction, and the real-time longitudinal vibration amplitude of the tool during the machining process is obtained by processing the sensing signal; the bending vibration sensing piezoelectric ceramic PZT-BS (2-1) implanted in the tool body senses the vibration of the tool in the bending vibration direction, and the in-situ sensing of the real-time bending vibration amplitude of the tool during the machining process is achieved by processing the bending vibration sensing signal; the sensing actuation piezoelectric ceramic group (2) and the rear end cover (1) are electrically isolated by the insulating layer (3), so as to prevent the piezoelectric ceramic electrical signal from short-circuiting and ensure the stable operation of the piezoelectric ceramic.

3. A sensor-actuated integrated longitudinal-bending composite ultrasonic drilling tool handle according to claim 1, characterized in that: By applying two AC signals (signal A and signal B) with the same frequency but different phases to the bending vibration actuated piezoelectric ceramic PZT-BA (2-2) and the longitudinal vibration actuated piezoelectric ceramic PZT-LA (2-4), the elliptical motion of the tool tip within a period T can be obtained. The longitudinal vibration is used to achieve the axial ironing effect of the tool, while the bending vibration is used to achieve the intermittent cutting effect of the side edge. The longitudinal vibration and the bending vibration are spatially orthogonal to each other under the applied phase difference Φ = 90°, ensuring that the intermittent cutting and ironing effects can be achieved simultaneously within one cycle. By changing the phase angle Φ between signal A and signal B, the elliptical trajectory can be adjusted to achieve the intensity adjustment of the ironing effect and the intermittent cutting effect.

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