CN110299866A - The accurate piezoelectric straight line mobile platform and operation mode of frame structure driving - Google Patents

Abstract

The invention discloses the accurate piezoelectric straight line mobile platforms and operation mode of a kind of driving of frame structure, middle position is provided with the driving foot of protrusion on the inside of frame structure oscillator matrix, bending vibration excitation ceramics in face are pasted in the opposite outside of frame structure oscillator matrix and driving foot, frame structure oscillator matrix two sides corresponding with bending vibration excitation ceramics in face and driving foot are pasted with bending vibration excitation ceramics outside face respectively, and impact faces guide rail intersects vertical with groove；Mobile station is installed, correspondence contacts enough with the driving on the inside of frame structure oscillator matrix on the frame side of mobile station, and the lower frame of mobile station is corresponding with guide rail in frame structure oscillator matrix.The resonance effects of bending vibration modes drives driving foot coupling to form elliptical trajectory outside bending vibration modes and face in the face of vibrator component, to alternately push mobile station mobile.Linear movement platform of the invention pushes mobile station using multiple drivings enough, can increase exponentially out force density, speed and keep its operation more stable.

Description

Precision piezoelectric linear moving platform driven by square frame structure and its working mode

technical field

The invention belongs to piezoelectric precision drive technology, in particular to a precision piezoelectric linear moving platform driven by a square frame structure and its working mode.

technical background

Ultrasonic motor (piezoelectric motor) as a direct drive device, its working principle is different from traditional electromagnetic motor, it uses the inverse piezoelectric effect of piezoelectric material to convert electrical energy into mechanical energy of elastic body vibration, so that the elastic body surface particles generate Periodic trajectory movement, and through the friction coupling between the stator and the mover, the microscopic vibration is converted into the macroscopic motion of the mover; in addition, the ultrasonic motor drives the mover by the micron-level vibration of the surface particles of the stator, which can reach submicron level of positioning accuracy. Therefore, it is more widely used than traditional electromagnetic motors in aerospace, weaponry, high-precision instruments and other high-precision occasions with special requirements. Since the 1980s, many scholars at home and abroad have devoted themselves to the research and development of ultrasonic motors, a new type of micro-motor, which has made ultrasonic motors develop rapidly in the world with their own unique advantages, and has been favored by many scientific research institutions and The attention of related industries. According to the motion form of the mover, ultrasonic motors can be divided into linear type and rotary type. Among them, the technology of rotary type ultrasonic motor has become more and more mature. Technology conflicts proliferate, designs are complex, and development is slow. However, considering that the linear ultrasonic motor has strong environmental compatibility, it is more suitable for robotics, biomedical engineering, micro-electromechanical systems and other fields that have high requirements for linear motion. Therefore, it is necessary to conduct in-depth research on linear ultrasonic motors. In terms of foreign research, the world's first linear ultrasonic motor is the traveling wave linear ultrasonic motor proposed by Japanese scholar Shida Nensheng in 1982. Since then, Japan has been at the forefront of ultrasonic motor technology research and application. In 1989, scholar Tomikawa developed a standing wave linear ultrasonic motor, which became the first one to introduce LUSM into the standing wave field; in 1998, Kurosawa used the out-of-plane modes of two Langevin oscillators at an angle θ to develop a An ultrasonic motor with a V-shaped stator, which synthesizes an elliptical motion trajectory at the apex of the V-shaped structure, thereby driving the slider to move horizontally and linearly; in 2000, the Israeli Kyoccra company successfully used a standing wave linear ultrasonic motor to drive a two-dimensional Precision motion platform, its ultra-low-speed model products have a positioning accuracy of 10nm, a position resolution of more than 1nm, and a minimum speed of 10nm/s; German PI company Vyshnevskyy proposed a single-phase drive linear ultrasonic motor in 2005 and successfully commercialized it. Among them, the stator of the M-661 linear moving platform weighs only 10g, the maximum speed can reach 600mm/s, and the thrust can reach 1.5N. In China, in 2009, Zhao Chunsheng of Nanjing University of Aeronautics and Astronautics, who was the first to study ultrasonic motor drive technology in China, developed a patch-type linear ultrasonic motor. The thrust reaches 5.2N, and the no-load speed reaches 7mm/s; Dr. Liu Yingxiang of Harbin Institute of Technology and others proposed a bipedal drive linear ultrasonic motor based on the longitudinal vibration composite mode in 2012, using a horizontal piezoelectric transducer structure to connect two A piezoelectric transducer placed vertically, the structure adopts the integrated form of duralumin alloy, the test results show that under the electrical excitation signal with a frequency of 25.3KHz and a voltage amplitude of 200V, the motor double-driven feet can output a maximum speed of 610mm/s , Thrust 32N. Generally speaking, the structural forms of the linear ultrasonic motors that have been introduced are still extremely limited, and the performance of the linear ultrasonic motors has been greatly improved.

Contents of the invention

The purpose of the present invention is to propose a precision piezoelectric linear moving platform driven by a box structure and its working mode, so that the motion position resolution of the linear moving platform can reach the micron level, and it has a response speed of millisecond level, resulting in a higher operating speed and output greater thrust.

In view of the above purpose, the present invention adopts the following technical solutions: a precision piezoelectric linear moving platform driven by a square frame structure, including a vibrator assembly, a mobile platform and a base, the vibrator assembly includes a square frame structure vibrator base, in-plane bending vibration excitation Ceramics, out-of-plane bending vibration excitation ceramics; the vibrator base of the square frame structure is surrounded by an upper rod body, a lower rod body, a left rod body and a right rod body, and the upper, lower, left and right rod bodies are all in the shape of a cuboid with a protrusion in the middle of the inner side The four corners of the vibrator base of the square frame structure are provided with connection ends, the thickness of the connection end is slightly thinner than the thickness of the rod body, and there are through holes; the outside of the vibrator base of the square frame structure and the drive foot are pasted with in-plane bending vibration excitation Out-of-plane bending vibration excitation ceramics are pasted on both sides of the square frame structure vibrator base corresponding to the in-plane bending vibration excitation ceramics and the driving feet, and the square frame structure vibrator bases at both ends of the in-plane bending vibration excitation ceramics are provided with with screw holes;

The mobile platform has a "ten" strip structure, including an L-shaped plate, an elastic gasket, and an adjusting screw; the L-shaped plate is composed of a frame plate perpendicular to each other and a horizontal plate of a solid structure, and the two frames of the L-shaped plate The plates face each other and are connected with each other through adjusting screws, and the two horizontal structural plates face each other and are connected with each other through adjusting screws, and elastic gaskets are installed between the L-shaped plates;

The base includes a rectangular plate, the longitudinal centerline of the rectangular plate is provided with a guide rail, and the transverse centerline is provided with a groove, the guide rail and the groove are perpendicular to each other and the surface of the groove is lower than the guide rail; the bottom surface of the groove is equipped with an elastic washer, and the rectangular plate Fixing bolts are installed under the four corners;

The lower rod body of the vibrator assembly is fixed and installed in the groove of the base by bolts; the mobile platform is installed in the matrix of the vibrator with a square frame structure, and the frame edge of the mobile platform is in corresponding contact with the driving foot inside the vibrator matrix with a square structure structure, and the mobile platform The lower frame edge corresponds to the guide rail.

A working mode of a precision piezoelectric linear moving platform driven by a square frame structure, characterized in that it includes an in-plane bending vibration mode and an out-of-plane bending vibration mode of a vibrator assembly,

The in-plane bending vibration mode is the bending vibration of the upper rod body, the lower rod body, the left rod body and the right rod body based on the plane of the vibrator base of the box structure to the center of the plane or away from the center. The in-plane bending vibration mode is determined by the inverse piezoelectric effect Excitation, by applying a simple harmonic excitation voltage to the in-plane bending vibration excitation ceramics, the upper rod body, the lower rod body, the left rod body and the right rod body are excited to reciprocate according to the mode shape of the in-plane bending vibration mode; the vibration state of the upper rod body and the lower rod body are consistent, The reciprocating vibration is carried out toward the center of the base plane of the vibrator of the square frame structure or away from the center; the vibration state of the left rod body is consistent with that of the right rod body, and the reciprocating vibration is carried out toward the center of the base plane of the square structure vibrator body or away from the center, and the vibration state of the upper rod body and the lower rod body is the same as that of the left rod body The vibration states of the rod body and the right rod body are symmetrically opposite, so that the driving feet of the upper rod body and the lower rod body and the driving feet of the left rod body and the right rod body are alternately kept in contact with or separated from the mobile platform;

The out-of-plane bending vibration mode is the bending vibration of the upper rod body, the lower rod body, the left rod body and the right rod body along the positive and negative directions perpendicular to the plane of the box structure vibrator base body based on the plane of the box structure vibrator base body; the out-of-plane bending vibration mode The state is excited by the inverse piezoelectric effect. By applying a simple harmonic excitation voltage to the out-of-plane bending vibration excitation ceramics, the upper rod body, the lower rod body, the left rod body and the right rod body are excited to reciprocate according to the mode shape of the out-of-plane bending vibration mode; the upper rod body and the The vibration state of the lower rod body is consistent, and the reciprocating vibration is performed along the positive and negative directions perpendicular to the plane of the vibrator base body of the box structure; the vibration state of the left and right rod bodies is consistent, and the reciprocating vibration is performed along the positive and negative directions perpendicular to the plane of the base body of the box structure vibrator; and The vibration state of the upper rod body and the lower rod body is symmetrically opposite to the vibration state of the left rod body and the right rod body; so that the driving feet of the upper rod body and the lower rod body and the driving feet of the left rod body and the right rod body alternately push the mobile platform to move;

Taking the center of the vibrator matrix of the box structure as the coordinate origin, the surface of the vibrator matrix of the box structure is the xoy plane, and the normal direction of the surface of the vibrator matrix of the box structure is the z direction, by exciting the in-plane bending vibration mode and the surface The resonance effect of the outer bending vibration mode makes the driving feet of the upper rod body and the lower rod body coupled on the xoz plane to form an elliptical motion trajectory; z to move.

The technical effects of the present invention are as follows: 1. The precision piezoelectric linear moving platform driven by a square frame structure can realize precise movement, and its repeated positioning accuracy can reach micron and submicron levels. 2. The vibrator matrix with a square frame structure is used to directly push the mobile platform, which can improve the response speed and efficiency of the linear mobile platform. 3. Using multiple driving feet to push the mobile platform can double the output density and speed and make its operation more stable. It has broad application prospects in industrial precision positioning, precision drive of micro servo actuators and other applications.

Description of drawings

Fig. 1 is the three-dimensional structure schematic diagram of the present invention;

FIG. 2 is a schematic plan view of the vibrator assembly 1 in the present invention;

FIG. 3 is a schematic diagram of the three-dimensional structure of the mobile station 2 in the present invention;

Fig. 4 is the three-dimensional structure schematic diagram of L-shaped plate 21 among the present invention;

FIG. 5 is a schematic diagram of the three-dimensional structure of the base 3 in the present invention;

6 is a schematic plan view of the in-plane bending vibration mode of the vibrator assembly 1 in the present invention;

7 is a schematic perspective view of the out-of-plane bending vibration mode of the vibrator assembly 1 in the present invention;

Fig. 8 is a schematic plan view of the arrangement of the piezoelectric ceramics of the vibrator assembly 1 in the present invention and its configuration of piezoelectric polarization and power supply;

Fig. 9a is a schematic plan view of the first step of the linear motion of the mobile platform pushed by the vibrator base 11 of the box structure within one vibration cycle; Fig. 9b is a side view of Fig. 9a; Fig. 9c is a top view of Fig. 9a;

Fig. 10a is a schematic plan view of a second step in which the vibrator base 11 of a square frame structure pushes the mobile platform to perform linear motion within one vibration cycle; Fig. 10b is a side view of Fig. 10a; Fig. 10c is a top view of Fig. 10a;

Fig. 11a is a schematic plan view of the third step in which the vibrator base 11 of the box structure pushes the mobile platform to perform linear motion within one vibration cycle; Fig. 11b is a side view of Fig. 11a; Fig. 11c is a top view of Fig. 11a;

Fig. 12a is a schematic plan view of the fourth step in which the vibrator base 11 of a square frame structure pushes the mobile platform to perform linear motion within one vibration cycle; Fig. 12b is a side view of Fig. 12a; Fig. 12c is a top view of Fig. 12a;

In the figure: 1- vibrator assembly, 11- frame structure vibrator base, 111- upper rod body, 112- lower rod body, 113- left rod body, 114- right rod body, 115- driving foot, 116- connecting end, 12- in-plane Bending vibration excited ceramics, 13-out-of-plane bending vibration excited ceramics;

2-mobile platform, 21-L-shaped plate, 211-frame plate, 212-horizontal plate, 22-elastic gasket, 23-adjusting screw;

3-base, 31-rectangular plate, 311-guide rail, 312-groove, 32-elastic washer, 33-fixing bolt.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the present invention will be further described:

As shown in FIGS. 1 to 5 , the precision piezoelectric linear moving platform driven by a box structure includes a vibrator assembly 1 , a moving platform 2 and a base 3 . The vibrator assembly 1 is composed of a vibrator base 11 with a square frame structure, an in-plane bending vibration excitation ceramic 12 and an out-of-plane bending vibration excitation ceramic 13; Surrounded by the right rod body 114, the upper, lower, left and right rod bodies are all in the form of a cuboid and a raised driving foot 115 is provided in the middle of the inner side; the four corners of the vibrator base body 11 with a square frame structure are provided with connecting ends 116, and the thickness of the connecting ends 116 is slightly Thinner than the thickness of the rod body and provided with through holes to reduce the stiffness of the rod body and increase the amplitude of the working mode; the in-plane bending vibration excitation ceramic 12 includes 4 pieces of piezoelectric ceramic sheets, which are respectively pasted on the frame structure On the outer side of the vibrator base 11 opposite to the driving foot 115, the out-of-plane bending vibration excitation ceramic 13 includes 8 pieces of piezoelectric ceramics, which are symmetrically pasted on the corresponding square frames of the in-plane bending vibration excitation ceramic 12 and the driving foot 115. Both sides of the structural vibrator base 11; the square frame structure vibrator base 11 at both ends of the in-plane bending vibration excitation ceramic 12 is provided with screw holes for the fixed connection between the vibrator assembly 1 and the base 3;

The mobile platform 2 is composed of an L-shaped plate 21, an elastic washer 22, and an adjusting screw 23. The overall structure is in the shape of a "cross", and its four frame sides are in corresponding contact with the driving feet 115 inside the vibrator base body 11 of the square frame structure; The L-shaped plate 21 is composed of mutually perpendicular frame plates 211 and horizontal plates 212 of a solid structure. The two frame plates 211 of the L-shaped plate 21 are opposite and connected to each other by adjusting screws 23. The two horizontal structural plates 212 are opposite and are connected by adjusting screws 23. Connected to each other, the L-shaped plates 21 are connected with elastic gaskets 22, and the distance between the L-shaped plates can be adjusted by using the elastic gaskets 22 and adjusting screws 23, so as to achieve the adjustment of the preload between the vibrator assembly 1 and the mobile platform 2 the goal of;

Described base 3 is made of rectangular plate 31, elastic washer 32, fixing bolt 33, and rectangular plate 31 is provided with guide rail 311 on longitudinal center line, and transverse center line is provided with groove 312, and guide rail 311 and groove 312 intersect vertically and groove The surface is lower than the guide rail 311, and the lower frame edge of the mobile platform 2 corresponds to the guide rail 311; screw holes are provided at both ends of the transverse center line of the groove 312, and the lower rod body 112 of the vibrator assembly 1 is fixed and installed in the groove 312 by bolts, and the vibrator assembly Elastic washers 32 are installed between the lower rod body 112 of 1 and the groove 312 to avoid direct contact between the two and provide pre-tightening force; fixed bolts 33 are installed under the four corners of the rectangular plate 31 .

As shown in Figures 6 to 7, the working modes of the precision piezoelectric linear motion platform driven by the box structure include the in-plane bending vibration mode and the out-of-plane bending vibration mode of the vibrator assembly 1:

The in-plane bending vibration mode is the bending vibration of the upper rod body 111, the lower rod body 112, the left rod body 113, and the right rod body 114 based on the plane of the vibrator matrix 11 of the box structure toward the center of the plane or away from the center. The in-plane bending vibration mode Excited by the inverse piezoelectric effect, by applying a cosine excitation voltage to the in-plane bending vibration excitation ceramic 12, the upper rod body 111, the lower rod body 112, the left rod body 113 and the right rod body 114 are excited to reciprocate according to the mode shape of the in-plane bending vibration mode; The upper rod body 111 is in the same vibration state as the lower rod body 112, and reciprocates toward the center of the plane of the vibrator base 11 with a square frame structure or deviates from the center; Carry out reciprocating vibration, and due to the principle of conservation of momentum, the vibration state of the upper rod body 111 and the lower rod body 112 is symmetrically opposite to the vibration state of the left rod body 113 and the right rod body 114, so that the driving feet 115 of the upper rod body 111 and the lower rod body 112 are aligned with the left rod body 113 and the driving foot 115 of the right rod body 114 alternately keeps in contact with or separates from the mobile platform 2;

The out-of-plane bending vibration mode is that the upper rod body 111, the lower rod body 112, the left rod body 113, and the right rod body 114 flexurally vibrate based on the plane of the vibrator base body 11 of the box structure along the positive and negative directions perpendicular to the plane of the base body 11 of the box structure structure; The out-of-plane bending vibration mode is excited by the inverse piezoelectric effect. By applying a sinusoidal excitation voltage to the out-of-plane bending vibration excitation ceramic 13, the upper rod body 111, the lower rod body 112, the left rod body 113 and the right rod body 114 are excited according to the out-of-plane bending vibration mode. The vibration mode is reciprocating; the upper rod body 111 and the lower rod body 112 have the same vibration state, and reciprocate vibration along the positive and negative directions perpendicular to the plane of the vibrator base 11 of the box structure; the left rod body 113 and the right rod body 114 have the same vibration state, and are perpendicular to The positive and negative directions of the plane of the vibrator matrix 11 of the square structure vibrate reciprocatingly; and due to the principle of conservation of momentum, the vibration state of the upper rod body 111 and the lower rod body 112 is symmetrically opposite to the vibration state of the left rod body 113 and the right rod body 114; so that the upper rod body 111 and the The driving feet 115 of the lower rod body 112 and the driving feet 115 of the left rod body 113 and the right rod body 114 alternately push the mobile platform 2 to move;

Taking the center of the vibrator matrix 11 with a square structure as the origin of coordinates, the plane where the vibrator matrix 11 is located is the xoy plane, and the normal direction of the plane where the vibrator base 11 is located is the z direction. Bending vibration mode, out-of-plane bending vibration mode and vibration coupling, so that the driving feet 115 of the upper rod body 111 and the lower rod body 112 are coupled on the xoz plane to form an elliptical motion track, and the driving feet 115 of the left rod body 113 and the right rod body 114 are in the yoz The surface coupling forms an elliptical motion trajectory, thereby alternately pushing the mobile platform 2 to move along the z direction.

Embodiment: The precision piezoelectric linear moving platform driven by the frame structure of the present invention includes a vibrator assembly 1, a moving platform 2 and a base 3, see Fig. 1 to Fig. 5 . The mobile platform 2 is installed in the vibrator assembly 1, and contacts the driving feet 115 inside the square frame structure vibrator base 11 through the four frame sides; at the same time, the lower frame side of the mobile platform 2 is located on the guide rail 311 of the base 3, and the vibrator The lower rod body 112 of the component 1 is fixedly installed in the groove 312 of the base 3 by bolts.

As shown in FIG. 2 , the vibrator assembly 1 includes a vibrator base body 11 with a square frame structure, in-plane bending vibration excitation ceramics 12 and out-of-plane bending vibration excitation ceramics 13 . The vibrator base 11 with a square frame structure is surrounded by a vertically symmetrical upper rod body 111, a lower rod body 112, and a left-right symmetrical left rod body 113 and a right rod body 114; The thickness of 116 is slightly thinner than that of the rod body and a through hole is provided to reduce the rigidity of the rod body and increase the vibration amplitude of the working mode. The upper, lower, left and right rod bodies are all in the shape of a cuboid and a protruding driving foot 115 is provided in the middle of the inner side. The in-plane bending vibration excitation ceramic 12 includes 4 pieces of piezoelectric ceramics, which are respectively pasted on the outer side of the vibrator base 11 with a square frame structure and the drive foot 115, and the out-of-plane bending vibration excitation ceramic 13 includes 8 pieces of piezoelectric ceramics slices, and are respectively symmetrically pasted on both sides of the vibrator base 11 with a square frame structure corresponding to the in-plane bending vibration excitation ceramic 12 and the driving foot 115 . The thickness of the driving foot 115 is greater than that of the piezoelectric ceramic sheet, and the surface of the driving foot 115 parallel to the in-plane bending vibration excitation ceramic 12 is coated with a wear-resistant material with a large friction coefficient to increase the friction between the driving foot 115 and the mobile platform 2 Driving force, thrust and service life of the linear moving platform. Screw holes are provided on the vibrator base 11 with a square frame structure at both ends of the in-plane bending vibration excitation ceramic 12 for the fixed connection between the vibrator assembly 1 and the base 3 .

As shown in Fig. 1, Fig. 3 and Fig. 4, the mobile station 2 includes an L-shaped plate 21, an elastic washer 22, and an adjusting screw 23. The driving feet 115 on the inner side of the substrate 11 are in direct contact; the horizontal direction of the L-shaped plate 21 is a solid plate 212, and screw holes are provided at the two corners of the right end; the vertical direction is a frame plate 211, and screw holes are provided at the two corners of the upper end; The two frame plates 211 of the plate 21 are opposite and connected to each other by adjusting screws 23, and the two horizontal structural plates 212 are opposite and connected to each other by adjusting screws 23; elastic gaskets 22 are installed between the L-shaped plates 21, and the elastic gaskets 22 There are 8 pieces; the distance between the L-shaped plates can be adjusted through the elastic gasket 22 and the adjusting screw 23, so as to achieve the purpose of adjusting the preload between the vibrator assembly 1 and the mobile platform 2 .

As shown in Figures 1 and 5, the base 3 includes a rectangular plate 31, an elastic washer 32, and a fixing bolt 33. The longitudinal centerline of the rectangular plate 31 is provided with a guide rail 311, and the transverse centerline is provided with a groove 312. The guide rail 311 and the recessed The grooves 312 are perpendicular to each other and the groove surface is lower than the guide rail 311. The lower frame edge of the mobile platform 2 corresponds to the guide rail 311. Screw holes are provided at both ends of the transverse center line of the groove 312. The lower rod body 112 of the vibrator assembly 1 is fixed and installed by bolts. In the groove 312 , an elastic washer 32 is installed between the lower rod body 112 of the vibrator base 11 of the square frame structure and the groove 312 to avoid direct contact between the two and provide pre-tightening force. There are two elastic washers 32 . Fixing bolts 33 are installed under the four corners of the rectangular plate 31 for fixing the base 3 on other mechanisms.

As shown in Figures 6 and 7, the working mode of the linear moving platform of the present invention includes the upper and lower symmetrical upper rod body 111 and the lower rod body 112 of the vibrator assembly 1, and the left and right symmetrical left rod body 113 and right rod body 114 in the xoy plane toward the coordinate origin Or the in-plane bending vibration mode deviating from the coordinate origin, and the out-of-plane bending vibration mode of reciprocating vibration along the z direction, wherein the in-plane bending vibration mode realizes the dynamic contact or separation between the driving foot 115 and the mobile platform 2, and the surface The external bending vibration mode realizes that the driving foot 115 alternately pushes the mobile platform 2 to move along the z direction.

Using the in-plane bending vibration to excite the ceramic 12 and the out-of-plane bending vibration to excite the ceramic 13 to excite the resonance or near-resonance of the two-phase working mode of the rod body, and drive the driving foot 115 placed inside the upper rod body 111 and the lower rod body 112 to make an elliptical motion on the xoz plane The driving foot 115 inside the left rod body 113 and the right rod body 114 makes an elliptical motion on the yoz plane, and then by means of the frictional coupling between the driving foot 115 and the mobile platform 2, the mobile platform 2 is pushed to make a linear motion along the z direction.

In order to make the upper rod body 111, the lower rod body 112 and the driving feet 115 inside the left rod body 113 and the right rod body 114 be coupled on the xoz and yoz planes to form elliptical motion trajectories respectively, the natural frequencies of the two-phase working modes of the rod bodies are required to be as close or equal as possible . Moreover, in order to prevent excessive mechanical noise when the linear moving platform is working, especially in order to enable the linear moving platform to output a higher speed, it is necessary to rationally configure the structural size of the vibrator assembly 1 so that the two-phase modal frequencies tend to be consistent and in the same position. Ultrasound frequency domain.

As shown in Fig. 2, Fig. 6 and Fig. 7, the in-plane bending vibration excitation ceramic 12 includes four high-performance PZT8 piezoelectric ceramic sheets, and these ceramic sheets are respectively located on the outer side of the vibrator base 11 with a square frame structure and the driving foot 115. And paste them on the peak and trough of the in-plane bending vibration mode shape of the rod respectively.

As shown in Fig. 2, Fig. 6 and Fig. 7, the out-of-plane bending vibration excitation ceramic 13 includes 8 high-performance PZT8 piezoelectric ceramic sheets, and these ceramic sheets are respectively located at the corresponding positions of the in-plane bending vibration excitation ceramic 12 and the driving foot 115. The two sides of the vibrator matrix 11 of the square frame structure are pasted on the peaks and troughs of the out-of-plane bending vibration mode shape of the rod body respectively.

As shown in Figure 8, in order to effectively and correctly excite the in-plane bending vibration mode, it is necessary to carry out reasonable polarization and power supply configuration on the in-plane bending vibration excitation ceramic 12, and the in-plane bending vibration excitation ceramic 12 can be divided into two groups according to symmetry, The in-plane bending vibration excitation ceramics 12 on the surface of the upper rod body 111 and the lower rod body 112 form a group, the in-plane bending vibration excitation ceramics 12 on the surface of the left rod body 113 and the right rod body 114 form a group, and the piezoelectric ceramic sheets in the same group are made of the same direction of polarization. As shown in Figure 8, "+" indicates that the piezoelectric polarization direction is perpendicular to the pasting surface and is the same as the normal direction, facing away from the box structure vibrator base 11, and "-" indicates that the piezoelectric polarization direction is perpendicular to the pasting surface and is the same as the normal direction. The direction of the line is opposite to the vibrator base 11 of the square frame structure. This requires: the in-plane bending vibration excitation ceramics 12 pasted on the surface of the upper rod body 111 and the lower rod body 112 are all perpendicular to the paste surface and polarized in the same direction as the normal, facing away from the square structure vibrator base 11; pasted on the left rod body 113 The in-plane bending vibration excitation ceramics 12 on the surface of the right rod body 114 are perpendicular to the paste surface and opposite to the normal direction and point to the direction of the square structure vibrator substrate 11; all the surfaces of the in-plane bending vibration excitation ceramics 12 are connected to the same frequency Cosine excitation voltage . At the same time, it is required that the bonding surfaces of the in-plane flexural vibration excitation ceramic 12 and the vibrator base 11 of the square frame structure be grounded and connected to zero excitation voltage.

As shown in Figure 8, in order to effectively and correctly excite the out-of-plane bending vibration mode, it is necessary to carry out reasonable polarization and power supply configuration for the out-of-plane bending vibration excitation ceramic 13, and the out-of-plane bending vibration excitation ceramic 13 can be divided into two groups according to the symmetry, The out-of-plane bending vibration excitation ceramics 13 on the surfaces of the upper rod body 111 and the lower rod body 112 form a group, and the out-of-plane bending vibration excitation ceramics 13 on the surfaces of the left rod body 113 and the right rod body 114 form a group. To this end, it is required that the out-of-plane bending vibration excitation ceramics 13 pasted on the front of the upper rod body 111 and the lower rod body 112 are perpendicular to the pasting surface and polarized in the same direction as the normal, facing away from the square structure vibrator base 11; pasted on the upper rod body 111 The out-of-plane flexural vibration excitation ceramic 13 on the opposite side of the lower rod body 112 is perpendicular to the paste surface, and is polarized in the direction opposite to the normal direction to the square vibrator base 11 . The out-of-plane flexural vibration excitation ceramics 13 pasted on the front surfaces of the left rod body 113 and the right rod body 114 are perpendicular to the paste surface, and polarized in the direction opposite to the normal direction to the square structure vibrator base 11 . The out-of-plane bending vibration excitation ceramics 13 pasted on the opposite sides of the left rod body 113 and the right rod body 114 are perpendicular to the paste surface, and polarized in the same direction as the normal direction away from the square structure vibrator base 11 . The surfaces of all out-of-plane bending vibration excited ceramics 13 are fed with the same frequency sinusoidal excitation voltage , and at the same time, it is required that the sticking surfaces of the out-of-plane bending vibration excitation ceramic 13 and the vibrator base 11 of the square frame structure are grounded and connected to zero excitation voltage.

As shown in Fig. 9a to Fig. 12c, the elliptical motion trajectory of the driving foot 115 on the xoz and yoz planes is respectively connected with the upper rod body 111, the lower rod body 112, the left rod body 113 and the right rod body 114 through the out-of-plane bending vibration mode It is formed by the vibration coupling of the inner bending vibration mode. If a vibration cycle T of the vibrator base 11 with a square structure is divided into four stages, and the initial state of the vibrator base 11 with a square frame structure is assumed to be: the upper rod body 111 is in the maximum upward bending shape in the plane, and the lower rod body 112 is in the maximum in-plane state. In a downward curved shape, the left rod body 113 is in the largest right-curved shape in the plane, and the right rod body 114 is in the largest left-curved shape in the plane; each rod body is in a zero-curved shape outside the plane, and the elliptical motion track is formed through the following four stages:

As shown in Figures 9a to 9c (Step 1), during the time period of 0~T/4, the in-plane bending vibration mode makes the left rod body 113 recover from the maximum right-bending shape in the plane to the zero-bending shape in the plane, and the right rod body 114 The in-plane maximum left-bending state is restored to the in-plane zero-bending state, and the out-of-plane bending vibration mode makes the left rod body 113 and the right rod body 114 bend from the out-of-plane zero-bending shape to the out-of-plane maximum forward-bending shape, resulting in the left rod body 113 and the right The driving foot 115 inside the rod body 114 is in contact with the mobile platform 2 and the driving foot 115 inside the left rod body 113 travels from A1 to A2, and the driving foot 115 inside the right rod body 114 travels from B1 to B2, pushing the mobile platform 2 along the positive direction of the z -axis At the same time, the in-plane bending vibration mode makes the upper rod body 111 recover from the maximum up-bending shape in the plane to the zero-bending shape in the plane, and the lower rod body 112 recovers from the maximum down-bending shape in the plane to the zero-bending shape in the plane, The out-of-plane bending vibration mode makes the upper rod body 111 and the lower rod body 112 bend from the out-of-plane zero-bending shape to the out-of-plane maximum back-bending shape, so that the driving feet 115 inside the upper rod body 111 and the lower rod body 112 are separated from the mobile platform 2 and the upper rod body The driving foot 115 on the inner side of 111 travels from C1 to C2, and the driving foot 115 on the inner side of the lower rod body 112 travels from D1 to D2.

As shown in Figures 10a to 10c (Step 2), during the time period T/4~T/2, the in-plane bending vibration mode makes the left rod body 113 bend from the in-plane zero-bend to the in-plane maximum left-bend, right-bend The rod body 114 is bent from the in-plane zero-bending shape to the in-plane maximum right-bending shape, and the out-of-plane bending vibration mode makes the left rod body 113 and the right rod body 114 recover from the out-of-plane maximum forward bending shape to the out-of-plane zero-bending shape, causing the left rod body 113 And the driving foot 115 inside the right rod body 114 is separated from the mobile platform 2 and the driving foot 115 inside the left rod body 113 travels from A2 to A3, and the driving foot 115 inside the right rod body 114 travels from B2 to B3; meanwhile, in-plane bending The vibration mode makes the upper rod body 111 bend from zero bending in the plane to the maximum downward bending in the plane, the lower rod 111 bends from zero bending in the plane to the maximum upward bending in the plane, and the bending vibration mode outside the plane makes the upper rod 111 and the lower rod body 112 recover from the maximum backbend out-of-plane to the zero-bend out-of-plane shape, so that the driving feet 115 inside the upper rod body 111 and the lower rod body 112 are in contact with the mobile platform 2 and the driving feet 115 inside the upper rod body 111 travel from C2 to C3, the driving foot 115 inside the lower rod body 112 travels from D2 to D3, pushing the mobile platform 2 to move further along the positive direction of the z -axis.

As shown in Fig. 11a ~ Fig. 11c (Step 3), in the time period T/2 ~ 3T/4, the in-plane bending vibration mode makes the left rod 113 recover from the maximum left-bending in-plane to the zero-bending in-plane, right The rod body 114 recovers from the largest right-bending shape in the plane to the zero-bending shape in the plane, and the out-of-plane bending vibration mode makes the left rod body 113 and the right rod body 114 bend from the zero-bending shape out-of-plane to the largest back-bending shape outside the plane, so that the left rod body 113 And the driving foot 115 inside the right rod body 114 is separated from the mobile platform 2 and the driving foot 115 inside the left rod body 113 travels from A3 to A4, and the driving foot 115 inside the right rod body 114 travels from B3 to B4; meanwhile, in-plane bending The vibration mode makes the upper rod body 111 recover from the maximum downward bending state in the plane to the zero bending state in the plane, the lower rod body 111 recovers from the maximum upward bending state in the plane to the zero bending state in the plane, and the out-of-plane bending vibration mode makes the upper rod body 111 and the lower rod body 112 are bent from the out-of-plane zero-bending shape to the out-of-plane maximum forward bending shape, so that the driving feet 115 on the upper rod body 111 and the lower rod body 112 are in contact with the mobile platform 2 and the driving feet 115 on the inner side of the upper rod body 111 travel from C3 to C4, the driving foot 115 inside the lower rod body 112 travels from D3 to D4, pushing the mobile platform 2 to move further along the positive direction of the z -axis.

As shown in Figures 12a to 12c (Step4), in the period of 3T/4~T, the in-plane bending mode makes the left rod body 113 bend from the in-plane zero-bending shape to the in-plane maximum right-bending shape, and the right rod body 114 is bent by The in-plane zero-curved shape becomes the largest in-plane left-curved shape. The out-of-plane bending vibration mode makes the left rod body 113 and the right rod body 114 recover from the out-of-plane maximum backbend state to out-of-plane zero-bend state. Cause the driving feet 115 inside the left rod body 113 and the right rod body 114 to contact the mobile platform 2, and the driving feet 113 inside the left rod body 113 travel from A4 to A1, and the driving feet 115 inside the right rod body 114 travel from B4 to B1 to promote the movement Stage 2 moves one step along the positive direction of the z -axis. At the same time, the in-plane bending vibration mode makes the upper rod body 111 bend from zero-bending in-plane to maximum up-bending in-plane, and the lower rod 111 bends from zero-bending in-plane to maximum down-bending in-plane, and bends out-of-plane Vibration makes the upper rod body 111 and the lower rod body 112 return from the maximum forward bending shape out of the plane to the zero bending shape outside the plane, so that the driving feet 115 inside the upper rod body 111 and the lower rod body 112 are separated from the mobile platform 2 and the driving feet inside the upper rod body 111 115 travels from C4 to C1, and the driving foot 115 on the inner side of the lower rod body 112 travels from D4 to D1.

As shown in Figures 9a to 12c, every time the vibrator base 11 with a square frame structure completes one vibration cycle T, in the yoz plane, the driving foot 115 inside the left rod body 113 will complete the elliptical motion via A1-A2-A3-A4-A1 Trajectory, the driving foot 115 inside the right rod body 114 will complete the elliptical motion trajectory via B1-B2-B3-B4-B1; on the xoz plane, the driving foot 115 inside the upper rod body 111 will complete the elliptical motion trajectory via C1-C2-C3-C4- For the elliptical motion trajectory of C1, the driving foot 115 inside the lower rod body 112 will complete the elliptical motion trajectory via D1-D2-D3-D4-D1, and then alternately push the mobile platform 2 to move four steps along the positive direction of the z -axis. When the vibrator base 11 with a square frame structure repeats the above-mentioned vibration cycle, it will push the mobile platform 2 to move forward along the positive direction of the z -axis. phase relationship, the direction of motion of the mobile station 2 will be reversed.

Claims (2)

1. A precision piezoelectric linear moving platform driven by a square frame structure, including a vibrator assembly, a mobile platform and a base, characterized in that the vibrator assembly includes a square frame structure vibrator base, in-plane bending vibration excitation ceramics, Vibration excitation ceramics; the vibrator base body of the square frame structure is surrounded by an upper rod body, a lower rod body, a left rod body and a right rod body, and the upper, lower, left and right rod bodies are all in the form of a cuboid and a raised driving foot is arranged in the middle of the inner side; The four corners of the vibrator base of the frame structure are provided with connecting ends, the thickness of the connecting ends is slightly thinner than that of the rod body, and a through hole is provided; on the outer side of the vibrator base of the frame structure opposite to the driving foot, an in-plane bending vibration excitation ceramic is pasted, which is consistent with the Out-of-plane bending vibration excitation ceramics are respectively pasted on both sides of the in-plane bending vibration excitation ceramics and the corresponding square frame structure vibrator base of the driving foot, and screw holes are provided on the square frame structure vibrator bases at both ends of the in-plane bending vibration excitation ceramics; The mobile platform has a "ten" strip structure, including an L-shaped plate, an elastic gasket, and an adjusting screw; the L-shaped plate is composed of a frame plate perpendicular to each other and a horizontal plate of a solid structure, and the two frames of the L-shaped plate The plates face each other and are connected with each other through adjusting screws, and the two horizontal structural plates face each other and are connected with each other through adjusting screws, and elastic gaskets are installed between the L-shaped plates; The base includes a rectangular plate, the longitudinal centerline of the rectangular plate is provided with a guide rail, and the transverse centerline is provided with a groove, the guide rail and the groove are perpendicular to each other and the surface of the groove is lower than the guide rail; the bottom surface of the groove is equipped with an elastic washer, and the rectangular plate Fixing bolts are installed under the four corners; The lower rod body of the vibrator assembly is fixed and installed in the groove of the base by bolts; the mobile platform is installed in the matrix of the vibrator with a square frame structure, and the frame edge of the mobile platform is in corresponding contact with the driving foot inside the vibrator matrix with a square structure structure, and the mobile platform The lower frame edge corresponds to the guide rail. 2. A working mode based on the mobile platform according to claim 1, characterized in that: the in-plane bending vibration mode and the out-of-plane bending vibration mode comprising the vibrator assembly, The in-plane bending vibration mode is the bending vibration of the upper rod body, the lower rod body, the left rod body and the right rod body based on the plane of the vibrator base of the box structure to the center of the plane or away from the center. The in-plane bending vibration mode is determined by the inverse piezoelectric effect Excitation, by applying a simple harmonic excitation voltage to the in-plane bending vibration excitation ceramics, the upper rod body, the lower rod body, the left rod body and the right rod body are excited to reciprocate according to the mode shape of the in-plane bending vibration mode; the vibration state of the upper rod body and the lower rod body are consistent, The reciprocating vibration is carried out toward the center of the base plane of the vibrator of the square frame structure or away from the center; the vibration state of the left rod body is consistent with that of the right rod body, and the reciprocating vibration is carried out toward the center of the base plane of the square structure vibrator body or away from the center, and the vibration state of the upper rod body and the lower rod body is the same as that of the left rod body The vibration states of the rod body and the right rod body are symmetrically opposite, so that the driving feet of the upper rod body and the lower rod body and the driving feet of the left rod body and the right rod body are alternately kept in contact with or separated from the mobile platform; The out-of-plane bending vibration mode is the bending vibration of the upper rod body, the lower rod body, the left rod body and the right rod body along the positive and negative directions perpendicular to the plane of the box structure vibrator base body based on the plane of the box structure vibrator base body; the out-of-plane bending vibration mode The state is excited by the inverse piezoelectric effect. By applying a simple harmonic excitation voltage to the out-of-plane bending vibration excitation ceramics, the upper rod body, the lower rod body, the left rod body and the right rod body are excited to reciprocate according to the mode shape of the out-of-plane bending vibration mode; the upper rod body and the The vibration state of the lower rod body is consistent, reciprocating vibration along the positive and negative directions perpendicular to the plane of the vibrator base of the square frame structure; the vibration state of the left rod body and the right rod body is consistent, along the plane reciprocating vibration in the positive and negative directions of the surface; and the vibration state of the upper rod body and the lower rod body is symmetrically opposite to the vibration state of the left rod body and the right rod body; so that the driving feet of the upper rod body and the lower rod body alternate with the driving feet of the left rod body and the right rod body promote the movement of the mobile station; Taking the center of the vibrator matrix of the box structure as the coordinate origin, the surface of the vibrator matrix of the box structure is the xoy plane, and the normal direction of the surface of the vibrator matrix of the box structure is the z direction, by exciting the in-plane bending vibration mode and the surface The resonance effect of the outer bending vibration mode makes the driving feet of the upper rod body and the lower rod body coupled on the xoz plane to form an elliptical motion trajectory; z to move.