Single drive magnetostrictive-piezoelectric machine parallel ultrasonic elliptical vibration system and method

Abstract

The single-excitation magnetostrictive-piezoelectric mechanical parallel ultrasonic elliptical vibration system and method disclosed by the application comprises a variable amplitude rod, the variable amplitude rod comprises an input large end as a vibration input end and an output small end as a vibration output end, the input large end is fixedly connected with a magnetostrictive transduction branch and a piezoelectric transduction branch respectively, the magnetostrictive transduction branch and the piezoelectric transduction branch are connected in series through a circuit and are electrically connected with an ultrasonic power supply. The beneficial effect is that the application can realize ultrasonic elliptical vibration by using a single AC signal, the inductive impedance of the coil and the capacitive impedance of the piezoelectric ceramic stack can be used for electrical compensation when connected in series, and the application has the characteristics of less driving channel, simple system structure and convenient impedance matching.

Description

Technical Field

[0001] This invention belongs to the field of power ultrasonic vibration technology, and relates to a single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system, as well as a single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration method. Background Technology

[0002] Ultrasonic vibration technology has been widely used in ultrasonic cutting, ultrasonic grinding, ultrasonic welding, precision machining, surface strengthening, and micro / nano manufacturing. Compared with one-dimensional longitudinal vibration, the output end of an ultrasonic elliptical vibration system can generate vibration components with a certain phase difference in two mutually perpendicular directions, thereby forming periodic elliptical trajectory vibration. This is beneficial for improving the contact and friction state between the tool and the workpiece, reducing cutting force, and improving material removal efficiency and surface quality.

[0003] Existing ultrasonic elliptical vibration systems typically employ two piezoelectric transducers or two sets of piezoelectric ceramic stacks as excitation elements to excite two orthogonal vibration modes of the system. This usually requires two ultrasonic power supplies or a multi-channel drive device to apply in-phase but co-frequency electrical signals to the two excitation branches, with the amplitude, frequency, and phase of each signal adjusted separately. The drive circuit and control system of this type of vibration system are relatively complex, placing high demands on the drive power supply. When the operating temperature, external load, or contact state between the tool and workpiece changes, the resonant frequencies of the two vibration modes are prone to change, thus affecting the stability of elliptical vibration machining.

[0004] To simplify the drive power supply and its control system, some existing technologies convert single longitudinal vibration into combined longitudinal-bending or longitudinal-torsional vibration by incorporating inclined slots, asymmetric structures, inclined beams, or other vibration mode conversion structures on the amplitude transformer. Such designs rely primarily on the specific geometry of the amplitude transformer to achieve coupling between different vibration modes. Their output trajectory is closely related to the structural dimensions, material parameters, and boundary conditions of the amplitude transformer, making structural design quite challenging.

[0005] Piezoelectric ceramics and giant magnetostrictive materials are two commonly used functional materials in power ultrasonic transducers. Piezoelectric transducers typically exhibit capacitive impedance, while the excitation coils of giant magnetostrictive transducers typically exhibit inductive impedance. Combining these two types of transducers allows for the utilization of their differences in transduction mechanisms, impedance characteristics, and mechanical responses to provide different vibration excitation characteristics for ultrasonic vibration systems. Existing magnetostrictive-piezoelectric hybrid transducer vibration systems are mainly used to broaden the operating frequency band, adjust resonance characteristics, or improve impedance matching. However, current technology lacks a simple and easily implemented solution for utilizing the vibration phase difference between the magnetostrictive and piezoelectric transducer branches within the same ultrasonic amplitude transformer, and combining the two branches to excite longitudinal and bending vibrations respectively.

[0006] Therefore, it is necessary to invent a magnetostrictive-piezomechanical parallel hybrid ultrasonic vibration system driven by a single excitation signal. By utilizing the vibration phase difference between the magnetostrictive transducer branch and the piezoelectric transducer branch, the longitudinal and bending vibrations of the amplitude transformer are excited, thereby forming an elliptical vibration trajectory at the output end of the amplitude transformer. Summary of the Invention

[0007] The first objective of this invention is to provide a single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system, which solves the problems of complex structure and control circuit, high processing cost, and unstable operation of existing ultrasonic elliptical vibration systems.

[0008] Another objective of this invention is to provide a method for single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration.

[0009] The first technical solution adopted in this invention is a single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system, including an amplitude transformer. The amplitude transformer includes a large input end as the vibration input end and a small output end as the vibration output end. The large input end is fixedly connected to a magnetostrictive transducer branch and a piezoelectric transducer branch, respectively. The magnetostrictive transducer branch and the piezoelectric transducer branch are connected in series or in parallel through a circuit and electrically connected to an ultrasonic power supply.

[0010] The first technical solution of the present invention is further characterized by: The magnetostrictive transducer branch and the piezoelectric transducer branch are located in different regions of the large input end of the amplitude transformer. The vibration axes of both the magnetostrictive transducer branch and the piezoelectric transducer branch are parallel to the axis of the amplitude transformer, and the vibration axes of the magnetostrictive transducer branch, the piezoelectric transducer branch, and the amplitude transformer are located in the same plane. There is a first eccentric distance between the vibration axis of the piezoelectric transducer branch and the axis of the amplitude transformer, and a second eccentric distance between the vibration axis of the magnetostrictive transducer branch and the axis of the amplitude transformer. Both the first eccentric distance and the second eccentric distance are greater than zero.

[0011] The piezoelectric transducer branch includes a first pre-tightening bolt, a first rear cover plate, and a piezoelectric ceramic stack. The first pre-tightening bolt passes through the center of the first rear cover plate and the piezoelectric ceramic stack, and is connected to the large input end of the amplitude transformer rod by a thread.

[0012] The piezoelectric ceramic stack includes multiple piezoelectric sheets stacked along the axial direction, with electrode sheets disposed between adjacent piezoelectric sheets.

[0013] The magnetostrictive transducer branch includes a second pre-tightening bolt, a second rear cover plate, and a window-shaped magnetostrictive vibration unit. The second pre-tightening bolt passes through the second rear cover plate and the window-shaped magnetostrictive vibration unit in sequence and is connected to the input large end of the amplitude transformer by a thread.

[0014] The window-shaped magnetostrictive vibration unit includes two Terfenol-D rods, both of which are arranged parallel to the axis of the amplitude transformer and are parallel to each other. The two ends of the two Terfenol-D rods are connected by a first magnetic plate and a second magnetic plate, respectively. A permanent magnet is connected between the end of each Terfenol-D rod and the first magnetic plate, and between the end of each Terfenol-D rod and the second magnetic plate. The first magnetic plate abuts against the second rear cover plate, and the second magnetic plate abuts against the large input end of the amplitude transformer. A coil is sleeved on the outer periphery of each Terfenol-D rod, and the two coils are electrically connected in series. A second preload bolt passes through the first and second magnetic plates and is connected to the large input end of the amplitude transformer.

[0015] Two coils are electrically connected in series or parallel with the piezoelectric ceramic stack and are connected together to the ultrasonic power supply.

[0016] Another technical solution of the present invention is a single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration method, which employs the above-mentioned single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system and includes the following steps: S1. Connect the two coils in series or in parallel with the piezoelectric ceramic stack, and apply a single AC excitation signal through an ultrasonic power supply. S2. The magnetostrictive transducer branch generates the first axial vibration, and the piezoelectric transducer branch generates the second axial vibration. The first and second axial vibrations are transmitted to the large input end of the amplitude transformer, forming an axial resultant force and alternating bending moment, causing the small output end of the amplitude transformer to output an ultrasonic elliptical vibration trajectory.

[0017] Another feature of the technical solution of the present invention is that: The ultrasonic elliptical vibration trajectory includes longitudinal and transverse displacements. The longitudinal displacement is:

[0018] in, This represents longitudinal displacement, in μm. The amplitude is the longitudinal amplitude, in μm. Angular frequency, in rad / μs; The vibration time is expressed in μs. This represents the initial phase of the longitudinal vibration; The lateral displacement is:

[0019] in, This represents lateral displacement, in μm. The transverse amplitude is expressed in μm. This represents the initial phase of the transverse vibration.

[0020] The beneficial effects of this invention are: (1) The magnetostrictive transducer branch and the piezoelectric transducer branch are driven by the same AC excitation signal, eliminating the need for two independent ultrasonic power supplies and electrical signal phase adjustment devices, which helps to reduce the number of driving channels and simplify the system composition and control circuit.

[0021] (2) When the magnetostrictive transducer branch and the piezoelectric transducer branch are connected in series, the inductive impedance of the excitation coil and the capacitive impedance of the piezoelectric ceramic stack can be used for electrical compensation, which can reduce the reactive impedance of the drive circuit and reduce the complexity of the external impedance matching circuit.

[0022] (3) Two types of transducer branches, mechanical parallel and relatively eccentric arrangement, are used to directly excite the longitudinal and bending vibrations of the amplitude transformer. There is no need to set up mode conversion structures such as inclined slots and inclined beams on the amplitude transformer, thereby simplifying the structural design of the amplitude transformer and reducing its processing cost. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system of the present invention; Figure 2 This is a front view schematic diagram of the transducer structure of the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system of the present invention; Figure 3 This is a rear view schematic diagram of the transducer structure of the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system of the present invention; Figure 4 This is a mode shape diagram of the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system of the present invention; Figure 5 The elliptical vibration trajectory output by the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system of the present invention; Figure 6 This is a time-amplitude curve of the output of the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system of the present invention.

[0024] In the figure, 1. First preload bolt, 2. Second preload bolt, 3. First rear cover plate, 4. Second rear cover plate, 5. Amplitude rod, 6. Second magnetic conductive sheet, 7. First magnetic conductive sheet, 8. Piezoelectric sheet, 9. Electrode sheet, 10. Ultrasonic power supply, 11. Terfenol-D rod, 12. Coil, 13. Permanent magnet. Detailed Implementation

[0025] The following detailed description is provided in conjunction with the accompanying drawings and specific embodiments.

[0026] like Figure 1 , Figure 2 , Figure 3As shown, the present invention provides a single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system, including an amplitude transformer 5. The amplitude transformer 5 includes a large input end as the vibration input end and a small output end as the vibration output end. The large input end is fixedly connected to a magnetostrictive transducer branch and a piezoelectric transducer branch, respectively. The magnetostrictive transducer branch and the piezoelectric transducer branch are connected in series or in parallel through a circuit and electrically connected to an ultrasonic power supply 10.

[0027] The magnetostrictive transducer branch and the piezoelectric transducer branch together transmit axial vibration to the amplitude transformer 5, which acts on different regions of the large input end of the amplitude transformer 5, thus forming a mechanical parallel structure.

[0028] The magnetostrictive transducer branch and the piezoelectric transducer branch are located in different regions of the large input end of the amplitude transformer 5. The vibration axes of the magnetostrictive transducer branch and the piezoelectric transducer branch are both parallel to the axis of the amplitude transformer 5, and the vibration axes of the magnetostrictive transducer branch, the piezoelectric transducer branch, and the amplitude transformer 5 are all located in the same plane. There is a first eccentric distance between the vibration axis of the piezoelectric transducer branch and the axis of the amplitude transformer 5, and a second eccentric distance between the vibration axis of the magnetostrictive transducer branch and the axis of the amplitude transformer 5. Both the first eccentric distance and the second eccentric distance are greater than zero.

[0029] By adjusting the first and second eccentric distances, different moment distributions and trajectory adjustments can be achieved.

[0030] The piezoelectric transducer branch includes a first pre-tightening bolt 1, a first rear cover plate 3, and a piezoelectric ceramic stack. The first pre-tightening bolt 1 passes through the center of the first rear cover plate 3 and the piezoelectric ceramic stack, and is connected to the input large end of the amplitude transformer 5 by a thread.

[0031] The piezoelectric ceramic stack includes multiple piezoelectric sheets 8, which are stacked axially, with electrode sheets 9 disposed between adjacent piezoelectric sheets 8. The piezoelectric sheets 8 are polarized along the thickness direction and arranged in the same way as their axial deformation direction.

[0032] The magnetostrictive transducer branch includes a second pre-tightening bolt 2, a second rear cover plate 4, and a window-shaped magnetostrictive vibration unit. The second pre-tightening bolt 2 passes through the second rear cover plate 4 and the window-shaped magnetostrictive vibration unit in sequence and is connected to the input large end of the amplitude rod 5 by a thread.

[0033] The window-shaped magnetostrictive vibration unit includes two Terfenol-D rods 11, both of which are arranged parallel to the axis of the amplitude transformer 5 and are parallel to each other. The two ends of the two Terfenol-D rods 11 are connected by a first magnetic plate 7 and a second magnetic plate 6, respectively. A permanent magnet 13 is connected between the end of each Terfenol-D rod 11 and the first magnetic plate 7, and between the end of each Terfenol-D rod 11 and the second magnetic plate 6, to provide a static bias magnetic field along the axial direction to the Terfenol-D rod 11. The first magnetic plate 7 abuts against the second rear cover plate 4, and the second magnetic plate 6 abuts against the large input end of the amplitude transformer 5. A coil 12 is fitted around the outer periphery of each Terfenol-D rod 11, and the two coils 12 are electrically connected in series to generate an alternating magnetic field with the same direction in the window-shaped magnetic circuit. The first magnetic plate 7 and the second magnetic plate 6 are used to form a closed magnetic circuit to reduce magnetic leakage.

[0034] The second preload bolt 2 passes through the first magnetic sheet 7 and the second magnetic sheet 6 located in the second rear cover plate 4 and the window-type magnetostrictive unit and is connected to the input large end of the amplitude rod 5 by thread, so as to transmit the axial vibration generated by the Terfenol-D rod 11 to the input large end of the amplitude rod 5.

[0035] Two coils 12 are connected in series and electrically connected in series or parallel with the piezoelectric ceramic stack, and are jointly connected to the ultrasonic power supply 10.

[0036] Working principle: Coil 12 is electrically connected in series with a piezoelectric ceramic stack consisting of piezoelectric sheet 8 and electrode sheet 9, and both are connected to ultrasonic power supply 10. Specifically, two coils 12 are first connected in series to form a magnetostrictive excitation winding, which is then connected in series or parallel with the piezoelectric ceramic stack, and finally connected to ultrasonic power supply 10. Ultrasonic power supply 10 outputs a single-channel AC signal with a preset operating frequency, which acts simultaneously on coil 12 and piezoelectric ceramic stack. Under the action of alternating current, coil 12 generates an alternating magnetic field, causing the two Terfenol-D rods 11 to produce axial extension and contraction vibration; piezoelectric sheet 8 produces extension and contraction vibration under the action of alternating electric field.

[0037] When the vibration system is working, the impedance of coil 12 is inductive, while the impedance of the piezoelectric ceramic stack is capacitive. When the two are connected in series, the inductive reactance and capacitive reactance can cancel each other out in the series drive circuit, thereby reducing the reactive impedance of the drive circuit. The magnetostrictive transducer branch and the piezoelectric transducer branch are connected together at the large input end of the amplitude transformer 5. Due to the different mechanical structures of the two transducer branches, under the condition of relatively eccentric arrangement, the two axial forces further form an axial resultant force with a phase difference and an alternating bending moment, which respectively excite the longitudinal vibration and bending vibration of the amplitude transformer 5. The two are superimposed at the output end to form an ultrasonic elliptical vibration trajectory.

[0038] The axial force exerted by the piezoelectric transducer branch on the large input end of the amplitude transformer 5 is denoted as: The axial force exerted by the magnetostrictive transducer branch on the large input end of the amplitude transformer 5 is denoted as... The axial resultant force generated by the two energy conversion branches It can be represented as:

[0039] The axial resultant force is used to excite the longitudinal vibration of the amplitude transformer 5. Since the two transducer branches are located on opposite sides of the axis of the amplitude transformer 5, their axial forces also generate alternating bending moments in opposite directions relative to the centerline of the amplitude transformer 5. When the eccentricity of the two transducer branches is... At that time, the combined bending moment acting on the amplitude transformer 5 It can be represented as:

[0040] The combined bending moment is used to excite the bending vibration of the amplitude transformer 5, so that the amplitude transformer 5 simultaneously generates longitudinal vibration components and bending vibration components with a phase difference.

[0041] Let the longitudinal and lateral displacements of the output end of the amplitude transformer 5 be respectively:

[0042] in, This represents longitudinal displacement, in μm. The amplitude is the longitudinal amplitude, in μm. Angular frequency, in rad / μs; The vibration time is expressed in μs. This represents the initial phase of the longitudinal vibration; The lateral displacement is:

[0043] in, This represents lateral displacement, in μm. The transverse amplitude is expressed in μm. This represents the initial phase of the transverse vibration.

[0044] when and Both are non-zero, and the phase difference ( When the angle is not 0° or 180°, the output end of the amplitude transformer 5 forms a closed elliptical vibration trajectory within one vibration cycle.

[0045] The measured longitudinal displacement signal and the transverse displacement signal are curve fitted to obtain the elliptical vibration trajectory of the output end of the amplitude transformer 5.

[0046] like Figure 6As shown, both the longitudinal and lateral vibrations at the output end of the amplitude transformer 5 exhibit periodic changes, and both have the same resonant frequency and a non-zero phase difference. The time-amplitude curve can show the relative change relationship between the two vibration components over time, and is consistent with... Figure 5 The elliptical vibration trajectory shown corresponds to this. Therefore, it can be seen that in this embodiment, a single AC signal can simultaneously drive both the magnetostrictive transducer branch and the piezoelectric transducer branch. Furthermore, by utilizing the mechanical parallel connection and eccentric arrangement of the two transducer branches, an ultrasonic elliptical vibration trajectory is formed at the output end of the amplitude transformer 5.

[0047] This invention also provides a method for single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration, employing the above system and including the following steps: S1. Connect the two coils 12 in series and then connect them in series or in parallel with the piezoelectric ceramic stack, and apply a single AC excitation signal through the ultrasonic power supply 10. S2. The magnetostrictive transducer branch generates the first axial vibration, and the piezoelectric transducer branch generates the second axial vibration. The first and second axial vibrations are transmitted to the large input end of the amplitude transformer 5, forming an axial resultant force and an alternating bending moment, so that the small output end of the amplitude transformer 5 outputs an ultrasonic elliptical vibration trajectory.

[0048] Example 1 A single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system includes an amplitude transformer 5, which includes a large input end as the vibration input end and a small output end as the vibration output end. The large input end is fixedly connected to a magnetostrictive transducer branch and a piezoelectric transducer branch, respectively. The magnetostrictive transducer branch and the piezoelectric transducer branch are connected in series or in parallel through a circuit and electrically connected to an ultrasonic power supply 10.

[0049] Example 2 Based on Example 1, the magnetostrictive transducer branch and the piezoelectric transducer branch are located in different regions of the large input end of the amplitude transformer 5; the vibration axis of both the magnetostrictive transducer branch and the piezoelectric transducer branch are parallel to the axis of the amplitude transformer 5; there is a first eccentric distance between the vibration axis of the piezoelectric transducer branch and the axis of the amplitude transformer 5, and a second eccentric distance between the vibration axis of the magnetostrictive transducer branch and the axis of the amplitude transformer 5; both the first eccentric distance and the second eccentric distance are greater than zero.

[0050] The vibration axis of the magnetostrictive transducer branch, the vibration axis of the piezoelectric transducer branch, and the axis of the amplitude transformer 5 are located in the same plane.

[0051] The piezoelectric transducer branch includes a first pre-tightening bolt 1, a first rear cover plate 3, and a piezoelectric ceramic stack. The first pre-tightening bolt 1 passes through the center of the first rear cover plate 3 and the piezoelectric ceramic stack, and is threadedly connected to the large input end of the amplitude transformer 5.

[0052] The piezoelectric ceramic stack includes multiple piezoelectric sheets 8, which are stacked along the axial direction, and electrode sheets 9 are disposed between adjacent piezoelectric sheets 8.

[0053] Example 3 Based on Embodiment 2, the magnetostrictive transducer branch includes a second pre-tightening bolt 2, a second rear cover plate 4, and a window-shaped magnetostrictive vibration unit. The second pre-tightening bolt 2 passes through the second rear cover plate 4 and the window-shaped magnetostrictive vibration unit in sequence and is threadedly connected to the input large end of the amplitude rod 5.

[0054] The window-shaped magnetostrictive vibration unit includes two Terfenol-D rods 11, both of which are arranged parallel to the axis of the amplitude transformer 5 and are parallel to each other. The two ends of the two Terfenol-D rods 11 are connected by a first magnetic sheet 7 and a second magnetic sheet 6, respectively. A permanent magnet 13 is connected between the end of each Terfenol-D rod 11 and the first magnetic sheet 7 and between the end of each Terfenol-D rod 11 and the second magnetic sheet 6. The first magnetic sheet 7 abuts against the second rear cover plate 4, and the second magnetic sheet 6 abuts against the large input end of the amplitude transformer 5. A coil 12 is sleeved on the outer periphery of each Terfenol-D rod 11, and the two coils 12 are electrically connected in series. The second preload bolt 2 passes through the first magnetic sheet 7 and the second magnetic sheet 6 and is connected to the large input end of the amplitude transformer 5.

[0055] The two coils 12 are connected in series and electrically connected in series or parallel with the piezoelectric ceramic stack, and are jointly connected to the ultrasonic power supply 10.

[0056] Example 4 Based on Example 3, the dimensions of each part of the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system in this example are as follows: the small end diameter of the amplitude transformer 5 is 23mm, the length is 65mm, the length of the conical transition section is 20mm, the large end length is 20mm, and the diameter is 56mm; the outer diameter of the piezoelectric sheet 8 is 22mm, the thickness is 4mm, and there are 8 of them; the distance between the piezoelectric transducer branch and the axis of the amplitude transformer is 14mm; the length of the Terfenol-D rod 11 is 22mm, and the diameter is 18mm; the thickness of the first magnetic conductive sheet 7 and the second magnetic conductive sheet 6 is 3mm, the length is 32mm, and the width is 18mm; the thickness of the permanent magnet 13 is 3mm, and the diameter is 18mm; the length of the rear cover plate is 40mm, the width is 22mm, the height is 52mm, and the chamfer radius is 20mm. The distance between the magnetostrictive transducer branch and the axis of the amplitude transformer is also 14mm. Both excitation coils 12 are wound with enameled copper wire, with 200 turns and a wire diameter of 1mm. The two coils are wound in opposite directions.

[0057] Simulation calculations yielded Figure 4The vibration modes of the vibration system shown are as follows. Its resonant frequency is 18.199kHz, the amplitude is largest at the output end of the amplitude transformer, and it is a longitudinal bending vibration.

[0058] like Figure 5 As shown, the longitudinal displacement signal obtained from the simulation calculation is curve-fitted with the lateral displacement signal to obtain the elliptical vibration trajectory of the output end of the amplitude rod 5.

[0059] like Figure 6 As shown, both the longitudinal and lateral vibrations at the output end of the amplitude transformer 5 exhibit periodic changes.

[0060] Example 5 The single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration method, employing the above-mentioned single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system, includes the following steps: S1. Connect the two coils 12 in series and then connect them in series or in parallel with the piezoelectric ceramic stack, and apply a single AC excitation signal through the ultrasonic power supply 10. S2. The magnetostrictive transducer branch generates the first axial vibration, and the piezoelectric transducer branch generates the second axial vibration. When the first axial vibration and the second axial vibration are transmitted to the large input end of the amplitude transformer 5, the vibrations generated by the two have a phase difference, forming an axial resultant force and an alternating bending moment, so that the small output end of the amplitude transformer 5 outputs an ultrasonic elliptical vibration trajectory.

[0061] Example 6 Based on Example 5, the ultrasonic elliptical vibration trajectory includes longitudinal displacement and transverse displacement, with the longitudinal displacement being:

[0062] in, This represents longitudinal displacement, in μm. The amplitude is the longitudinal amplitude, in μm. Angular frequency, in rad / μs; The vibration time is expressed in μs. This represents the initial phase of the longitudinal vibration; The lateral displacement is:

[0063] in, This represents lateral displacement, in μm. The transverse amplitude is expressed in μm. This represents the initial phase of the transverse vibration.

Claims

1. A single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system, characterized in that, The system includes an amplitude transformer (5), which includes a large input end as the vibration input end and a small output end as the vibration output end. The large input end is fixedly connected to a magnetostrictive transducer branch and a piezoelectric transducer branch, respectively. The magnetostrictive transducer branch and the piezoelectric transducer branch are connected in series or in parallel through a circuit and electrically connected to an ultrasonic power supply (10).

2. The single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system according to claim 1, characterized in that, The magnetostrictive transducer branch and the piezoelectric transducer branch are located in different regions of the input large end of the amplitude transformer (5); the vibration axis of the magnetostrictive transducer branch and the vibration axis of the piezoelectric transducer branch are both parallel to the axis of the amplitude transformer (5), and the vibration axis of the magnetostrictive transducer branch, the vibration axis of the piezoelectric transducer branch and the axis of the amplitude transformer (5) are located in the same plane; there is a first eccentric distance between the vibration axis of the piezoelectric transducer branch and the axis of the amplitude transformer (5), and there is a second eccentric distance between the vibration axis of the magnetostrictive transducer branch and the axis of the amplitude transformer (5); both the first eccentric distance and the second eccentric distance are greater than zero.

3. The single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system according to claim 2, characterized in that, The piezoelectric transducer branch includes a first preload bolt (1), a first rear cover plate (3), and a piezoelectric ceramic stack. The first preload bolt (1) passes through the center of the first rear cover plate (3) and the piezoelectric ceramic stack, and is threadedly connected to the input large end of the amplitude transformer (5).

4. The single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system according to claim 3, characterized in that, The piezoelectric ceramic stack includes multiple piezoelectric sheets (8), which are stacked along the axial direction, and electrode sheets (9) are provided between adjacent piezoelectric sheets (8).

5. The single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system according to claim 4, characterized in that, The magnetostrictive transducer branch includes a second pre-tightening bolt (2), a second rear cover plate (4), and a window-shaped magnetostrictive vibration unit. The second pre-tightening bolt (2) passes through the second rear cover plate (4) in sequence, and the window-shaped magnetostrictive vibration unit is connected to the input large end of the amplitude rod (5) by a thread.

6. The single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system according to claim 5, characterized in that, The window-shaped magnetostrictive vibration unit includes two Terfenol-D rods (11), both of which are arranged parallel to the axis of the amplitude transformer (5) and are parallel to each other; the two ends of the two Terfenol-D rods (11) are connected by a first magnetic sheet (7) and a second magnetic sheet (6), respectively; the end of each Terfenol-D rod (11) is connected to the first magnetic sheet (7) and ... A permanent magnet (13) is connected between the end of the first magnetic plate (7) and the second magnetic plate (6); the first magnetic plate (7) abuts against the second rear cover plate (4), and the second magnetic plate (6) abuts against the input large end of the amplitude rod (5); a coil (12) is respectively sleeved on the outer periphery of each Terfenol-D rod (11), and the two coils (12) are electrically connected in series; the second pre-tightening bolt (2) passes through the first magnetic plate (7) and the second magnetic plate (6) and is connected to the input large end of the amplitude rod (5).

7. The single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system according to claim 6, characterized in that, The two coils (12) are connected in series and electrically connected in series or in parallel with the piezoelectric ceramic stack, and are jointly connected to the ultrasonic power supply (10).

8. A method for single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration, employing the single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration system as described in claim 7, characterized in that... Includes the following steps: S1. Connect the two coils (12) in series and then connect them in series or in parallel with the piezoelectric ceramic stack, and apply a single AC excitation signal through the ultrasonic power supply (10). S2, the magnetostrictive transducer branch generates the first axial vibration, the piezoelectric transducer branch generates the second axial vibration, the first axial vibration and the second axial vibration are transmitted to the input large end of the amplitude transformer (5) to form an axial resultant force and alternating bending moment, so that the output small end of the amplitude transformer (5) outputs an ultrasonic elliptical vibration trajectory.

9. The method for single-excitation magnetostrictive-piezomechanical parallel ultrasonic elliptical vibration according to claim 8, characterized in that, The ultrasonic elliptical vibration trajectory includes longitudinal displacement and lateral displacement, wherein the longitudinal displacement is: in, This represents longitudinal displacement, in μm. The amplitude is the longitudinal amplitude, in μm. Angular frequency, in rad / μs; The vibration time is expressed in μs. This represents the initial phase of the longitudinal vibration; The lateral displacement is: in, This represents lateral displacement, in μm. The transverse amplitude is expressed in μm. This represents the initial phase of the transverse vibration.

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