CN116742990A

CN116742990A - Multimode linear piezoelectric driver based on flexible hinge structure and working method thereof

Info

Publication number: CN116742990A
Application number: CN202310781256.XA
Authority: CN
Inventors: 李研; 王亮; 原路生; 金家楣
Original assignee: Nanjing University of Aeronautics and Astronautics
Current assignee: Nanjing University of Aeronautics and Astronautics
Priority date: 2023-06-29
Filing date: 2023-06-29
Publication date: 2023-09-12

Abstract

The invention discloses a multimode linear piezoelectric driver based on a flexible hinge structure and a working method thereof, wherein the piezoelectric driver comprises a shell, an output shaft, a pre-tightening bolt and a driving module; the driving module is arranged in the shell and comprises a first driving unit, a second driving unit and first to third fixing pieces; the first to third piezoelectric assemblies have the same structure and comprise a beam body, a first wedge block, a second wedge block, an adjusting bolt, a piezoelectric stack, a conductive block and first to third straight beam type flexible hinges. According to the invention, by controlling the time sequence and the frequency of the movement of the piezoelectric driving component in the driving module, the actuating shaft generates periodic movement of an asynchronous sequence, so that a high-precision and high-speed movement mode is realized; the invention has the characteristics of high reliability, large output thrust, high precision and the like, has better universality, is easy to popularize and has good economic benefit.

Description

Multimode linear piezoelectric driver based on flexible hinge structure and working method thereof

Technical Field

The invention relates to the field of piezoelectric driving, in particular to a multimode linear piezoelectric driver based on a flexible hinge structure and a working method thereof;

Background

The linear piezoelectric transmission device is an actuator based on piezoelectric effect and ultrasonic vibration, and has extremely wide application in the fields of biology, robots, machine manufacturing and the like, in particular to micro-nano control application due to the characteristics of high corresponding speed, high precision and the like; however, the output stroke is small, the output performance is single, and the application of the device is not wide enough; therefore, how to increase the output stroke and optimize the output performance of the linear piezoelectric transmission device becomes a main problem of the linear piezoelectric actuator that further widens the application range and improves the device performance;

disclosure of Invention

Aiming at the defects related to the background technology, the invention provides a multimode linear piezoelectric driver based on a flexible hinge structure and a working method thereof;

the invention adopts the following technical scheme for solving the technical problems:

the multimode linear piezoelectric driver based on the flexible hinge structure comprises a shell, an output shaft, a pre-tightening bolt and a driving module;

the output shaft is a cuboid and comprises two end faces and four side faces; the shell is hollow, and is provided with a first through hole and a second through hole for the output shaft to extend in and out; linear bearings matched with the output shaft are arranged in the first through hole and the second through hole, so that the output shaft can slide freely along the first through hole and the second through hole;

The driving module is arranged in the shell and comprises a first driving unit, a second driving unit and first to third fixing pieces;

the first driving unit and the second driving unit have the same structure and comprise a motion block, a driving foot, first to third piezoelectric assemblies and first to second connecting pieces;

the first to third piezoelectric assemblies have the same structure and comprise a beam body, a first wedge block, a second wedge block, an adjusting bolt, a piezoelectric stack, a conductive block and first to third straight beam type flexible hinges;

the beam body is a cuboid and comprises a first beam body end wall, a second beam body end wall and first to fourth beam body side walls which are vertically and fixedly connected end to end in sequence; the first beam body end wall is provided with an installation groove, the installation groove is a stepped through groove penetrating through the first beam body side wall and the third beam body side wall, and the first through groove, the second through groove and the third through groove which are communicated in sequence are formed in the direction from the second beam body end wall to the first beam body end wall; the first through groove, the second through groove and the third through groove are rectangular through grooves, the length direction of the first through groove is the same as the length direction of the beam body, the width direction of the first through groove is the same as the width direction of the beam body, the width of the first through groove is more than or equal to the width of the second through groove, and the width of the third through groove is more than or equal to the width of the second through groove;

The first wedge block and the second wedge block have the same structure and are cylinders with right trapezoid cross sections, and each cylinder comprises a first wedge block end wall, a second wedge block end wall and first to fourth wedge block side walls connected end to end, wherein the first wedge block end wall is parallel to the second wedge block end wall and is in a right trapezoid shape; the first wedge side wall is parallel to the third wedge side wall, the second wedge side wall is perpendicular to the first wedge side wall and the third wedge side wall respectively, and the area of the first wedge side wall is smaller than that of the third wedge side wall;

the first wedge block and the second wedge block are arranged in the first through groove, the second wedge block side wall of the first wedge block abuts against the side wall, close to the end wall of the second beam body, of the first through groove, and the second wedge block side wall of the first wedge block is positioned between the first wedge block side wall of the first wedge block and the second beam body side wall; the fourth wedge sidewall of the second wedge abuts against the fourth wedge sidewall of the first wedge, so that the second wedge sidewall of the second wedge is parallel to the second wedge sidewall of the first wedge;

the side wall of the second beam body is provided with an adjusting threaded through hole at the first through groove;

the adjusting bolt is connected with the adjusting threaded through hole in a threaded manner and extends into the first through groove to prop against the side wall of the second wedge block of the first wedge block, and is used for adjusting the distance between the side wall of the second wedge block and the side wall of the second wedge block of the first wedge block;

The conductive block is a cuboid and comprises a first conductive end wall, a second conductive end wall and first to fourth conductive side walls which are sequentially and vertically connected end to end;

the conduction block is arranged in the third through groove, one end of the first straight beam type flexible hinge is vertically fixedly connected with the end wall, close to the side wall of the fourth beam body, of the third through groove, and the other end of the first straight beam type flexible hinge is vertically fixedly connected with the fourth conduction side wall; one end of the second straight beam type flexible hinge is vertically and fixedly connected with the end wall, close to the side wall of the second beam body, of the third tee groove, and the other end of the second straight beam type flexible hinge is fixedly connected with the second conduction side wall; one end of the third straight beam type flexible hinge is vertically and fixedly connected with the first conducting end wall;

the piezoelectric stack is arranged in the second through groove, one end of the piezoelectric stack is propped against the side wall of the second wedge block, and the other end of the piezoelectric stack is propped against the second conductive end wall;

one end of the first connecting piece is fixedly connected with one end, close to the side wall of the second beam, of the first beam end wall of the first piezoelectric assembly, and the other end of the first connecting piece is fixedly connected with one end, close to the side wall of the fourth beam, of the first beam end wall of the second piezoelectric assembly, so that the beam of the first piezoelectric assembly is perpendicular to the beam of the second piezoelectric assembly; one end of the second connecting piece is fixedly connected with one end of the first beam body end wall of the second piezoelectric assembly, which is close to the second beam body end wall, and the other end of the second connecting piece is fixedly connected with one end of the first beam body end wall of the third piezoelectric assembly, which is close to the fourth beam body side wall, so that the beam body of the third piezoelectric assembly is perpendicular to the beam body of the second piezoelectric assembly, and the beam body of the third piezoelectric assembly and the beam body of the first piezoelectric assembly are collinear;

The motion block is arranged among the first piezoelectric component, the second piezoelectric component and the third piezoelectric component and is fixedly connected with the other end of the third straight beam type flexible hinge in the first piezoelectric component, the second piezoelectric component and the third piezoelectric component respectively;

the driving foot is arranged on one side of the motion block, which is far away from the second piezoelectric component;

one end, close to the first beam end wall, of the fourth beam side wall of the first piezoelectric component in the first driving unit is fixedly connected with one end, close to the first beam end wall, of the first beam side wall of the first piezoelectric component in the second driving unit through a first fixing piece, one end, close to the first beam end wall, of the fourth beam side wall of the second piezoelectric component in the first driving unit is fixedly connected with one end, close to the first beam end wall, of the first beam side wall of the second piezoelectric component in the second driving unit through a second fixing piece, and one end, close to the first beam end wall, of the fourth beam side wall of the third piezoelectric component in the first driving unit is fixedly connected with one end, close to the first beam end wall, of the first beam side wall of the third piezoelectric component in the second driving unit through a third fixing piece;

one end, close to the end wall of the first beam body, of the fourth beam body side wall of the first piezoelectric component in the second driving unit and one end, close to the end wall of the first beam body, of the fourth beam body side wall of the third piezoelectric component in the second driving unit are fixedly connected with the inner wall of the shell, so that driving feet of the first driving unit and the second driving unit are abutted against one side face of the output shaft;

The shell is provided with a pre-tightening threaded through hole matched with the pre-tightening bolt;

the pre-tightening bolt is connected with the pre-tightening threaded through hole in a threaded manner, stretches into the shell and abuts against the second fixing piece, and is used for adjusting the pre-tightening force between the driving feet of the first driving unit and the second driving unit and the output shaft.

As a further optimization scheme of the multi-mode linear piezoelectric driver based on the flexible hinge structure, the side walls of the output shaft, which are abutted against the driving feet of the first driving unit and the second driving unit, are provided with friction layers made of ceramic materials.

The invention also discloses a working method of the multimode linear piezoelectric driver based on the flexible hinge structure, wherein the first driving unit and the second driving unit adopt triangular waves for driving:

step A), the first driving unit and the second driving unit adopt triangular waves for synchronous driving:

if it is required to drive the output shaft in the forward direction:

step a.2.1.1), adjusting the pre-tightening bolts so that the driving feet of the first driving unit and the second driving unit apply pre-compression force Fn to the output shaft;

step A.2.1.2), driving the first piezoelectric component and the second piezoelectric component T for 1 second in the first driving unit and the second driving unit by ascending triangular wave, and enabling the first piezoelectric component and the second piezoelectric component to move to an elongation state so as to push the first piezoelectric component and the second piezoelectric component to move The motion blocks of the two driving units simultaneously generate forward motion, and the output shaft generates forward displacement x under the action of static friction force of the driving feet of the first driving unit and the second driving unit ₁ ；

Step A.2.1.3), driving the first piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit simultaneously by adopting descending triangular waves for 2 seconds, wherein T2 is smaller than T1, the first piezoelectric component and the second piezoelectric component move to a contracted state, the moving blocks of the first driving unit and the second driving unit are pulled to simultaneously generate reverse movement, and at the moment, the output shaft generates reverse displacement x under the action of sliding friction force of the driving feet of the first driving unit and the second driving unit ₂ ；

Step a.2.1.4), repeating steps a.2.1.2) through a.2.1.3) such that the output shaft moves in a stepwise forward direction, each cycle having a step length x ₁ -x ₂ ；

If the output shaft needs to be driven to move reversely:

step A.2.1), adjusting the pre-tightening bolt so that the driving feet of the first driving unit and the second driving unit apply pre-compression force Fn to the output shaft;

step A.2.2), driving the third piezoelectric component and the second piezoelectric component T for 1 second in the first and second driving units by ascending triangular waves, enabling the third piezoelectric component and the second piezoelectric component to move to an elongation state, pushing the moving blocks of the first and second driving units to simultaneously generate reverse movement, and enabling the output shaft to generate reverse displacement x under the action of static friction force of the driving feet of the first and second driving units ₁ ；

Step A.2.3), driving the third piezoelectric component and the second piezoelectric component in the first and second driving units by adopting descending triangular waves for 2 seconds, wherein T2 is smaller than T1, the third piezoelectric component and the second piezoelectric component move to a shortened state, the moving blocks of the first and second driving units are pulled to simultaneously generate forward movement, and at the moment, the output shaft generates forward displacement x under the action of sliding friction force of the driving feet of the first and second driving units ₂ ；

Step a.2.4), repeating steps a.2.2) to a.2.3) so that the output shaft moves in a step-by-step reverse direction, and the step length of each period is x ₁ -x ₂ ；

And B), alternately driving the first driving unit and the second driving unit by adopting triangular waves:

if it is required to drive the output shaft in the forward direction:

step B.1.1), adjusting the pre-tightening bolt so that the driving feet of the first driving unit and the second driving unit apply pre-compression force Fn to the output shaft;

step B.1.2), in an initial state, the first piezoelectric component and the second piezoelectric component in the second driving unit are in an elongation state; at 0 to t ₁ In seconds, the first driving unit drives the first piezoelectric component and the second piezoelectric component by ascending triangular waves, the first piezoelectric component and the second piezoelectric component in the first driving unit move to an elongation state, and the motion block of the first driving unit is pushed to generate forward motion; meanwhile, the first piezoelectric component and the second piezoelectric component in the second driving unit are driven by descending triangular waves, the first piezoelectric component and the second piezoelectric component in the second driving unit move to a contracted state, the moving block of the second driving unit is pulled to generate reverse movement, and at the moment, the forward movement generated by the moving block of the first driving unit is smaller than the reverse movement generated by the moving block of the second driving unit, so that the output shaft generates reverse displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit ₁ ；

Step B.1.3), at t ₁ To t ₂ In seconds, the ascending triangular wave is adopted to drive the first piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit simultaneously, the first piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit move to an extension state, the moving blocks of the first driving unit and the second driving unit are pushed to simultaneously generate forward movement, and the output shaft generates forward displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit ₂ ；

Step B.1.4), at t ₂ To t ₃ In seconds, the first piezoelectric component and the second piezoelectric component in the first driving unit are driven by descending triangular waves, the first piezoelectric component and the second piezoelectric component in the first driving unit move to a contracted state,pulling the motion block of the first driving unit to generate reverse motion; meanwhile, the ascending triangular wave is adopted to drive a first piezoelectric component and a second piezoelectric component in a second driving unit, the first piezoelectric component and the second piezoelectric component in the second driving unit move to an elongation state, and a motion block of the second driving unit is pushed to generate forward motion; because the reverse motion generated by the motion block of the first driving unit is smaller than the forward motion generated by the motion block of the second driving unit, the output shaft generates forward displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit ₃ ；

Step b.1.5), repeating steps b.1.2) through b.1.4) such that the output shaft moves in a stepwise forward direction, each cycle having a step length x ₂ +x ₃ -x ₁ ；

If the output shaft needs to be driven to move reversely:

step B.2.1), adjusting the pre-tightening bolts so that the driving feet of the first driving unit and the second driving unit apply pre-compression force Fn to the output shaft;

step B.2.2), in an initial state, the third piezoelectric component and the second piezoelectric component in the second driving unit are in an elongation state; at 0 to t ₁ In second, the third piezoelectric component and the second piezoelectric component are driven by ascending triangular waves in the first driving unit, and the third piezoelectric component and the second piezoelectric component in the first driving unit move to an elongation state to push the moving block of the first driving unit to generate reverse movement; meanwhile, the descending triangular wave is adopted to drive a third piezoelectric component and a second piezoelectric component in a second driving unit, the third piezoelectric component and the second piezoelectric component in the second driving unit move to a contracted state, a moving block of the second driving unit is pulled to generate forward movement, and at the moment, the reverse movement generated by the moving block of the first driving unit is smaller than the forward movement generated by the moving block of the second driving unit, so that an output shaft generates forward displacement x under the action of the common friction force of driving feet of the first driving unit and the second driving unit ₁ ；

Step B.2.3), at t ₁ To t ₂ In seconds, the rising triangular wave is adopted to drive the first driving unit and the second driving unit simultaneouslyThe third piezoelectric component and the second piezoelectric component in the first and the second driving units move to an extension state to push the moving blocks of the first and the second driving units to simultaneously generate reverse movement, and the output shaft generates reverse displacement x under the action of the common friction force of the driving feet of the first and the second driving units ₂ ；

Step B.2.4), at t ₂ To t ₃ In seconds, the descending triangular wave is adopted to drive a third piezoelectric component and a second piezoelectric component in the first driving unit, the third piezoelectric component and the second piezoelectric component in the first driving unit move to a contracted state, and a motion block of the first driving unit is pulled to generate forward motion; meanwhile, the ascending triangular wave is adopted to drive a third piezoelectric component and a second piezoelectric component in the second driving unit, the third piezoelectric component and the second piezoelectric component in the second driving unit move to an elongation state, and a motion block of the second driving unit is pushed to generate reverse motion; because the forward motion generated by the motion block of the first driving unit is smaller than the backward motion generated by the motion block of the second driving unit, the output shaft generates backward displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit ₃ ；

Step b.2.5), repeating steps b.2.2) through b.2.4) such that the output shaft moves in a stepwise forward direction, each cycle having a step length x ₂ +x ₃ -x ₁ 。

The invention also discloses a working method of the multimode linear piezoelectric driver based on the flexible hinge structure, wherein the first driving unit and the second driving unit adopt sine waves for driving:

step A), the first driving unit and the second driving unit adopt sine waves for synchronous driving:

if the output shaft needs to be driven to move forward, in the first driving unit and the second driving unit, the first piezoelectric component is driven by cos signal waves with the same amplitude and frequency, the second piezoelectric component is driven by sin signal waves with the same amplitude and frequency, and the third piezoelectric component is driven by cos signal waves with the same amplitude and frequency; the motion blocks of the first driving unit and the second driving unit are coupled to form elliptical motion to jointly push the output shaft to move;

step A.1.1), adjusting the pre-tightening bolt so that the driving feet of the first driving unit and the second driving unit apply pre-compression force Fn to the output shaft;

step A.1.2), in an initial state, a first piezoelectric component in the first driving unit and a second piezoelectric component in the second driving unit are in a contracted state, a third piezoelectric component is in an extended state and a second piezoelectric component is in an original length state;

At 0 to t ₁ In seconds, a first piezoelectric component in the first driving unit and a second driving unit stretches to an original length state, a third piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an stretching state, so that a moving block of the first driving unit and a moving block of the second driving unit simultaneously generate forward movement, and an output shaft generates forward displacement x under the action of common friction force of driving feet of the first driving unit and the second driving unit;

step A.1.3), at t ₁ To t ₂ In seconds, a first piezoelectric component in the first driving unit and a second driving unit moves to an extension state, a third piezoelectric component moves to a contraction state and the second piezoelectric component contracts to an original length state, so that a moving block of the first driving unit and a moving block of the second driving unit simultaneously generate forward movement, and an output shaft generates forward displacement x under the action of common friction force of driving feet of the first driving unit and the second driving unit;

step A.1.4), at t ₂ To t ₃ In seconds, the first piezoelectric component in the first driving unit and the second driving unit is contracted to an original length state, the third piezoelectric component is extended to an original length state, and the second piezoelectric component moves to a contracted state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate reverse movement, and the output shaft is static because the output shaft is not contacted with the driving feet of the first driving unit and the second driving unit in the process;

Step A.1.5), at t ₃ To t ₄ In seconds, the first piezoelectric component in the first driving unit and the second driving unit moves to a contracted state, the third piezoelectric component moves to an extended state, and the second piezoelectric component extends to an original length state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate reverse movement, and the output shaft and the first driving unit and the second driving unit simultaneously generate reverse movementThe drive feet of the drive units are not in contact, so that the output shaft is stationary;

step A.1.6), repeatedly executing the steps A.1.2) to A.1.5), so that the driving feet of the first driving unit and the second driving unit generate elliptical motion, the output shaft performs stepping forward motion, and the motion length of each period is 2x;

if the output shaft is required to be driven to move reversely, in the first driving unit and the second driving unit, cos signal waves with the same amplitude and frequency are adopted to drive the first piezoelectric component, sin signal waves with the same amplitude and frequency are adopted to drive the second piezoelectric component, and cos signal waves with the same amplitude and frequency are adopted to drive the third piezoelectric component; the motion blocks of the first driving unit and the second driving unit are coupled to form elliptical motion to jointly push the output shaft to move;

step A.2.1), adjusting the pre-tightening bolt to enable the driving feet of the first driving unit and the second driving unit to apply pre-compression force Fn to the output shaft;

Step A.2.2), in an initial state, a third piezoelectric component in the first driving unit and the second driving unit is in a contracted state, the first piezoelectric component is in an extended state and the second piezoelectric component is in an original length state;

at 0 to t ₁ In seconds, a third piezoelectric component in the first driving unit and the second driving unit stretches to an original length state, the first piezoelectric component contracts to the original length state, and the second piezoelectric component moves to the stretching state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate reverse movement, and the output shaft generates reverse displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit;

step A.2.3), at t ₁ To t ₂ In seconds, a third piezoelectric component in the first driving unit and the second driving unit moves to an extension state, the first piezoelectric component moves to a contraction state, and the second piezoelectric component contracts to an original length state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate reverse movement, and the output shaft generates reverse displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit;

step A.2.4), at t ₂ To t ₃ The third piezoelectric component in the first and second driving units contracts to the original length in secondsThe state that the first piezoelectric component stretches to the original length state and the second piezoelectric component moves to the contracted state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate forward movement, and the output shaft is static because the output shaft is not contacted with the driving feet of the first driving unit and the second driving unit in the process;

Step A.2.5), at t ₃ To t ₄ In seconds, the third piezoelectric component in the first and second driving units moves to a contracted state, the first piezoelectric component moves to an extended state, and the second piezoelectric component extends to an original length state, so that the moving blocks of the first and second driving units simultaneously generate forward movement, and the output shaft is static because the output shaft is not contacted with the driving feet of the first and second driving units in the process;

step A.2.6), repeatedly executing the steps A.2.2) to A.2.5), so that the driving feet of the first driving unit and the second driving unit generate elliptical motion, the output shaft performs stepping reverse motion, and the motion length of each period is 2x;

and B), alternately driving the first driving unit and the second driving unit by adopting sine waves:

if it is required to drive the output shaft in the forward direction:

meanwhile, a first piezoelectric component in a first driving unit and a third piezoelectric component in a second driving unit are driven by cos signal waves with the same amplitude and frequency, the third piezoelectric component in the first driving unit and the first piezoelectric component in the second driving unit are driven by cos signal waves with the same amplitude and frequency, the second piezoelectric component in the first driving unit is driven by sin signal waves with the same amplitude and frequency, and the second piezoelectric component in the second driving unit is driven by sin signal waves with the same amplitude and frequency; the motion blocks of the first driving unit and the second driving unit are coupled to form elliptical motion to alternately push the output shaft to move;

Step B.1.2), in an initial state, a first piezoelectric component in a first driving unit is in a contracted state, a third piezoelectric component in an extended state and a second piezoelectric component in an original length state, and in the second driving unit, the first piezoelectric component in the extended state, the third piezoelectric component in the contracted state and the second piezoelectric component in the original length state;

at 0 to t ₁ In seconds, the first piezoelectric component in the first driving unit stretches to an original length state, the third piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an stretching state, so that the motion block in the first driving unit generates forward motion, the first piezoelectric component in the second driving unit contracts to an original length state, the third piezoelectric component stretches to an original length state, and the second piezoelectric component moves to a shrinking state, so that the motion block in the second driving unit generates reverse motion, and the output shaft generates forward motion displacement x under the action of the friction force of the driving foot of the first driving unit;

step B.1.3), at t ₁ To t ₂ In second, the first piezoelectric component in the first driving unit moves to an extension state, the third piezoelectric component moves to a contraction state and the second piezoelectric component contracts to an original length state, so that the motion block in the first driving unit generates forward motion, the first piezoelectric component in the second driving unit moves to the contraction state, the third piezoelectric component moves to the extension state and the second piezoelectric component extends to the original length state, the motion block in the second driving unit generates reverse motion, and the output shaft generates forward motion displacement x under the action of the friction force of the driving foot in the first driving unit;

Step B.1.4), at t ₂ To t ₃ In seconds, the first piezoelectric component in the first driving unit contracts to an original length state, the third piezoelectric component extends to an original length state, and the second piezoelectric component moves to a contracted state, so that the motion block in the first driving unit generates reverse motion, the first piezoelectric component in the second driving unit extends to an original length state, the third piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an extended state, so that the motion block in the second driving unit generates forward motion, and the output shaft generates forward motion displacement x under the action of the friction force of the driving foot in the second driving unit;

step B.1.5), at t ₃ To t ₄ Within seconds, the first piezoelectric component in the first driving unit movesThe first piezoelectric component in the second driving unit moves to the extending state, the third piezoelectric component moves to the contracting state, the second piezoelectric component contracts to the original length state, the motion block in the second driving unit generates reverse motion, the second piezoelectric component contracts to the original length state, the motion block in the second driving unit generates forward motion displacement x under the action of friction force of the driving foot in the second driving unit, and the output shaft generates forward motion displacement x;

Step B.1.6), repeatedly executing the steps B.1.2) to B.1.5), so that the driving feet of the first driving unit and the second driving unit generate elliptical motion, the output shaft continuously moves forwards, and the motion length of each period is 4x;

if the output shaft needs to be driven to move reversely:

step B.2.1), adjusting the pre-tightening bolt to enable the driving feet of the first driving unit and the second driving unit to apply pre-compression force Fn to the output shaft;

meanwhile, a cos signal wave with the same amplitude and frequency is adopted to drive a third piezoelectric component in the first driving unit and a first piezoelectric component in the second driving unit, a cos signal wave with the same amplitude and frequency is adopted to drive the first piezoelectric component in the first driving unit and the third piezoelectric component in the second driving unit, a sin signal wave with the same amplitude and frequency is adopted to drive a second piezoelectric component in the first driving unit, and a sin signal wave with the same amplitude and frequency is adopted to drive the second piezoelectric component in the second driving unit; the motion blocks of the first driving unit and the second driving unit are coupled to form elliptical motion to alternately push the output shaft to move;

step B.2.2), in the initial state, the third piezoelectric component in the first driving unit is in a contracted state, the first piezoelectric component is in an extended state, the second piezoelectric component is in an original length state, the third piezoelectric component in the second driving unit is in an extended state, the first piezoelectric component is in a contracted state, and the second piezoelectric component is in an original length state;

At 0 to t ₁ In seconds, the third piezoelectric component in the first driving unit stretches to the original length state, the first piezoelectric component contracts to the original length state, and the second piezoelectric component moves to stretchThe state is that the motion block in the first driving unit moves reversely, the third piezoelectric component in the second driving unit contracts to the original length state, the first piezoelectric component extends to the original length state, the second piezoelectric component moves to the contracted state, the motion block in the second driving unit moves positively, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving foot in the first driving unit;

step B.2.3), at t ₁ To t ₂ In second, the third piezoelectric component in the first driving unit moves to an extension state, the first piezoelectric component moves to a contraction state, and the second piezoelectric component contracts to an original length state, so that the motion block in the first driving unit moves reversely, the third piezoelectric component in the second driving unit moves to the contraction state, the first piezoelectric component moves to the extension state, and the second piezoelectric component extends to the original length state, so that the motion block in the second driving unit moves positively, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving foot in the first driving unit;

Step B.2.4), at t ₂ To t ₃ In seconds, the third piezoelectric component in the first driving unit contracts to an original length state, the first piezoelectric component extends to an original length state, the second piezoelectric component moves to a contracted state, so that the motion block in the first driving unit generates forward motion, the third piezoelectric component in the second driving unit extends to an original length state, the first piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an extended state, so that the motion block in the second driving unit generates reverse motion, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving foot in the second driving unit;

step B.2.5), at t ₃ To t ₄ In seconds, the third piezoelectric component in the first driving unit moves to a contracted state, the first piezoelectric component moves to an extended state, and the second piezoelectric component extends to an original length state, so that the motion block in the first driving unit generates forward motion, the third piezoelectric component in the second driving unit moves to an extended state, the first piezoelectric component moves to a contracted state, and the second piezoelectric component contracts to an original length state, so that the motion block in the second driving unit generates reverse motion, and the output shaft is subjected to a second driving unitThe friction force of the driving foot in the element acts to generate reverse motion displacement x;

Step b.2.6), repeating the steps b.2.2) to b.2.5), so that the driving feet of the first and second driving units generate elliptical motion, the output shaft continuously moves reversely, and the motion length of each period is 4x.

The invention also discloses a working method of the multimode linear piezoelectric driver based on the flexible hinge structure, wherein the first driving unit and the second driving unit adopt trapezoidal waves for driving:

step A), the first driving unit and the second driving unit adopt trapezoidal waves for synchronous driving:

if the driving action shaft is required to move in the forward direction:

step A.1.2), in an initial state, the third piezoelectric component in the first and second driving units is in an elongation state;

at 0 to t ₁ In seconds, the second piezoelectric component is driven by rising oblique waves in the first driving unit and the second driving unit, the voltage of the third piezoelectric component is kept unchanged, the second piezoelectric component of the first driving unit and the second driving unit moves to an extension state, the third piezoelectric component is kept unchanged, the moving blocks of the first driving unit and the second driving unit are pushed to be close to the output shaft at the same time, and the driving foot is propped against the output shaft;

Step A.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component is driven by ascending oblique waves in the first driving unit and the second driving unit, the third piezoelectric component is driven by descending oblique waves and the voltage of the second piezoelectric component is kept unchanged, the first piezoelectric component of the first driving unit and the second driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged in the extension state, so that the moving blocks of the first driving unit and the second driving unit generate forward movement, and the output shaft generates forward movement displacement x under the action of the friction force of the driving feet in the first driving unit and the second driving unit;

step A.1.4), at t ₂ To t ₃ In seconds, the descending oblique waves are adopted in the first driving unit and the second driving unit to simultaneously drive the second piezoelectric component and keep the voltage of the first piezoelectric component unchanged, the second piezoelectric component of the first driving unit and the second driving unit is contracted to an original length state, the first piezoelectric component is kept unchanged in an extension state, and the moving blocks of the first driving unit and the second driving unit are pulled to be simultaneously far away from the output shaft;

step A.1.5), at t ₃ To t ₄ In seconds, the third piezoelectric component is driven by ascending oblique waves in the first driving unit and the second driving unit, and the first piezoelectric component is driven by descending oblique waves, the third piezoelectric component of the first driving unit and the second driving unit moves to an extension state, and the first piezoelectric component contracts to an original length state, so that the motion blocks of the first driving unit and the second driving unit generate reverse motion, and the output shaft is not contacted with the driving feet of the first driving unit and the second driving unit, so that the output shaft is stationary;

Step a.1.6), repeating steps a.1.2) to a.1.5), so that the output shaft moves forward stepwise, and the step length of each period is x;

if necessary, driving the motion shaft to move reversely:

step A.2.2), in an initial state, the first piezoelectric component in the first driving unit and the second driving unit is in an elongation state;

at 0 to t ₁ In seconds, the second piezoelectric component is driven by rising oblique waves in the first driving unit and the second driving unit, the voltage of the first piezoelectric component is kept unchanged, the second piezoelectric component in the first driving unit and the second driving unit moves to an extension state, the first piezoelectric component is kept unchanged, the moving blocks of the first driving unit and the second driving unit are pushed to be close to the output shaft at the same time, and the driving foot is propped against the output shaft;

step A.2.3), at t ₁ To t ₂ In seconds, the first and second driving units simultaneously drive the third piezoelectric component by using ascending oblique waves and simultaneously drive the first piezoelectric component by using descending oblique wavesThe voltage of the second piezoelectric component is kept unchanged, the third piezoelectric component of the first and second driving units moves to an extension state, the first piezoelectric component contracts to an original length state, the second piezoelectric component keeps unchanged in the extension state, the moving blocks of the first and second driving units move reversely, and the output shaft generates reverse movement displacement x under the action of friction force of driving feet in the first and second driving units;

Step A.2.4), at t ₂ To t ₃ In seconds, the descending oblique waves are adopted in the first driving unit and the second driving unit to simultaneously drive the second piezoelectric component and keep the voltage of the third piezoelectric component unchanged, the second piezoelectric component of the first driving unit and the second driving unit is contracted to an original length state, the third piezoelectric component is kept unchanged in an extension state, and the moving blocks of the first driving unit and the second driving unit are pulled to be simultaneously far away from the output shaft;

step A.2.5), at t ₃ To t ₄ In seconds, the first piezoelectric component is driven by ascending oblique waves in the first driving unit and the second driving unit, the third piezoelectric component is driven by descending oblique waves, the first piezoelectric component of the first driving unit and the second driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the moving blocks of the first driving unit and the second driving unit generate forward movement, and the output shaft is not contacted with the driving feet of the first driving unit and the second driving unit, so that the output shaft is stationary;

step a.2.6), repeatedly executing the steps a.2.2) to a.2.5), so that the output shaft moves in a stepping reverse direction, and the stepping length of each period is x;

step B), the first driving unit and the second driving unit adopt trapezoidal waves to alternately drive:

if it is required to drive the output shaft in the forward direction:

step B.1.2), in an initial state, the third piezoelectric component in the first driving unit is in an elongation state; the first piezoelectric component and the second piezoelectric component are in an elongation state in the second driving unit;

at 0 to t ₁ In seconds, driving the second piezoelectric component by using an ascending oblique wave in the first driving unit and keeping the voltage of the third piezoelectric component unchanged, enabling the second piezoelectric component of the first driving unit to move to an extension state, keeping the third piezoelectric component unchanged, pushing the moving block of the first driving unit to be close to the output shaft, driving the second piezoelectric component by using a descending oblique wave in the second driving unit and keeping the voltage of the first piezoelectric component unchanged, enabling the second piezoelectric component of the second driving unit to shrink to an original length state, keeping the first piezoelectric component unchanged, and pulling the moving block of the second driving unit to be simultaneously far away from the output shaft;

step B.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component is driven by the rising oblique wave in the first driving unit, the third piezoelectric component is driven by the falling oblique wave and the voltage of the second piezoelectric component of the first driving unit is kept unchanged, the first piezoelectric component of the first driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged, the moving block of the first driving unit moves forwards, the third piezoelectric component is driven by the rising oblique wave in the second driving unit and the first piezoelectric component is driven by the falling oblique wave, the third piezoelectric component of the second driving unit moves to an extension state, the first piezoelectric component contracts to the original length state, the moving block of the second driving unit moves reversely, and the output shaft generates forward movement displacement x under the action of friction force of the driving foot in the first driving unit;

Step B.1.4), at t ₂ To t ₃ In seconds, the second piezoelectric component is driven by the descending ramp wave in the first driving unit, the voltage of the first piezoelectric component is kept unchanged, the second piezoelectric component of the first driving unit is contracted to an original length state, the first piezoelectric component is kept unchanged in an extension state, the moving block of the first driving unit is pulled to be far away from the output shaft, the second piezoelectric component is driven by the ascending ramp wave in the second driving unit, the voltage of the third piezoelectric component is kept unchanged, the second piezoelectric component of the second driving unit is moved to an extension state, the third piezoelectric component is kept unchanged in an extension state, and the second driving unit is pushedThe motion block is close to the output shaft;

step B.1.5), at t ₁ To t ₂ In seconds, the third piezoelectric component is driven by the rising oblique wave in the first driving unit, the first piezoelectric component is driven by the falling oblique wave, the third piezoelectric component of the first driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the motion block of the first driving unit moves reversely, the third piezoelectric component is driven by the rising oblique wave in the second driving unit, meanwhile, the voltage of the second piezoelectric component of the second driving unit is kept unchanged, the first piezoelectric component of the second driving unit moves to the extension state, the third piezoelectric component contracts to the original length state, the second piezoelectric component is kept unchanged, the motion block of the second driving unit moves positively, and the output shaft generates forward motion displacement x under the action of friction force of the driving foot in the second driving unit;

Step b.1.6), repeating steps b.1.2) to b.1.5), such that the output shaft moves in a forward step, the step length of each cycle being 2x;

if the output shaft needs to be driven to move reversely:

step B.2.2), in an initial state, the first piezoelectric component in the first driving unit is in an elongation state; the third piezoelectric assembly and the second piezoelectric assembly are in an elongated state in the second drive unit;

at 0 to t ₁ In seconds, the second piezoelectric component is driven by the rising ramp wave in the first driving unit, the voltage of the first piezoelectric component is kept unchanged, the second piezoelectric component of the first driving unit moves to an extension state, the first piezoelectric component is kept unchanged, the moving block of the first driving unit is pushed to be close to the output shaft, the second piezoelectric component is driven by the falling ramp wave in the second driving unit, the voltage of the third piezoelectric component is kept unchanged, the second piezoelectric component of the second driving unit contracts to an original length state, and the third piezoelectric component is kept in an extension stateThe motion block of the second driving unit is pulled to be away from the output shaft at the same time;

Step B.2.3), at t ₁ To t ₂ In seconds, the third piezoelectric component is driven by the ascending oblique wave in the first driving unit, the first piezoelectric component is driven by the descending oblique wave, the voltage of the second piezoelectric component is kept unchanged, the third piezoelectric component of the first driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged, the motion block of the first driving unit moves reversely, the first piezoelectric component is driven by the ascending oblique wave in the second driving unit, the third piezoelectric component is driven by the descending oblique wave, the first piezoelectric component of the second driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the motion block of the second driving unit moves positively, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving foot in the first driving unit;

step B.2.4), at t ₂ To t ₃ In seconds, a descending oblique wave is adopted in the first driving unit to drive the second piezoelectric component and keep the voltage of the third piezoelectric component unchanged, the second piezoelectric component of the first driving unit is contracted to an original length state, the third piezoelectric component keeps unchanged in an extension state, the moving block of the first driving unit is pulled to be far away from the output shaft at the same time, an ascending oblique wave is adopted in the second driving unit to drive the second piezoelectric component and keep the voltage of the first piezoelectric component unchanged, the second piezoelectric component of the second driving unit moves to an extension state, the first piezoelectric component keeps unchanged in an extension state, and the moving block of the second driving unit is pushed to be close to the output shaft;

Step B.2.5), at t ₁ To t ₂ In seconds, the first piezoelectric component is driven by the ascending ramp wave and the third piezoelectric component is driven by the descending ramp wave in the first driving unit, the first piezoelectric component of the first driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the moving block of the first driving unit generates forward movement, the third piezoelectric component is driven by the ascending ramp wave in the second driving unit, and the first piezoelectric component is driven by the descending ramp wave and keeps the second pressureThe voltage of the electric component is unchanged, the third piezoelectric component of the second driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the second piezoelectric component keeps the extension state unchanged, the motion block of the second driving unit generates reverse motion, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving foot in the second driving unit;

step b.2.6), repeating steps b.2.2) through b.2.5) such that the output shaft steps in reverse motion, each cycle having a step length of 2x.

Compared with the prior art, the technical scheme provided by the invention has the following technical effects:

1. according to the invention, through the split design of the piezoelectric driving module and the actuating shaft, the output stroke of the device can be adjusted according to the selection of different numbers of piezoelectric driving modules or actuating shaft strokes;

2. The piezoelectric actuator is used as an excitation source, so that the piezoelectric actuator has high response speed and high precision, and can perform performance pre-tightening by changing input frequency, voltage and driving mode;

3. the invention is provided with two groups of mutually independent driving feet, can realize conversion between high-precision and high-speed output characteristics by pre-tightening different driving methods, and has higher guiding significance for application of the linear piezoelectric actuator;

drawings

FIG. 1 is a schematic diagram of the structure of the present invention;

FIG. 2 is a schematic cross-sectional view of the present invention;

FIG. 3 is a schematic diagram of a driving module according to the present invention;

FIG. 4 is a flow chart of the method of operation of the present invention employing triangular wave synchronous drive;

FIG. 5 is a flow chart of the working method of the invention using triangular wave alternate driving;

FIG. 6 is a flow chart of the method of operation of the present invention employing sine wave synchronous drive;

FIG. 7 is a flow chart of the method of operation of the present invention employing sine wave alternating drive;

FIG. 8 is a flow chart of the method of operation of the present invention employing trapezoidal wave synchronous drive;

fig. 9 is a flow chart of the working method of the invention using trapezoidal wave alternate driving.

In the figure, 1-shell, 2-driving module, 3-output shaft, 4-pretension bolt, 5-beam body of the first piezoelectric component of the first driving unit, 6-beam body of the second piezoelectric component of the first driving unit, 7-beam body of the third piezoelectric component of the second driving unit, 8-conductive block of the second piezoelectric component of the first driving unit, 9-first straight beam type flexible hinge of the second piezoelectric component of the first driving unit, 10-second straight beam type flexible hinge of the second piezoelectric component of the first driving unit, 11-third straight beam type flexible hinge of the second piezoelectric component of the first driving unit, 12-adjusting threaded through hole on the beam body of the second piezoelectric component of the second driving unit, 13-moving block of the first driving unit, 14-driving foot of the first driving unit, 15-first fixing piece, 16-second fixing piece, 17-third fixing piece.

Detailed Description

The technical scheme of the invention is further described in detail below with reference to the accompanying drawings:

this invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art;

as shown in fig. 1 and 2, the invention discloses a multimode linear piezoelectric driver based on a flexible hinge structure, which comprises a shell, an output shaft, a pre-tightening bolt and a driving module;

as shown in fig. 3, the first driving unit and the second driving unit have the same structure and each include a motion block, a driving foot, first to third piezoelectric components, and first to second connecting members;

The friction layers made of ceramic materials are arranged on the side walls of the output shaft, which are abutted against the driving feet of the first driving unit and the second driving unit, so that the friction force between the output shaft and the driving feet of the first driving unit and the second driving unit is improved, and the wear resistance of the output shaft is improved.

The linear bearings in the first through hole and the second through hole can be replaced by balls symmetrically arranged on two sides of the output shaft, as shown in fig. 2.

Step a), as shown in fig. 4, the first driving unit and the second driving unit adopt triangular waves to perform synchronous driving:

if it is required to drive the output shaft in the forward direction:

step A.2.1.2), driving the first piezoelectric component and the second piezoelectric component T for 1 second in the first driving unit and the second driving unit by ascending triangular waves, enabling the first piezoelectric component and the second piezoelectric component to move to an elongation state, pushing the moving blocks of the first driving unit and the second driving unit to simultaneously generate forward movement, and enabling the output shaft to generate forward displacement x under the action of static friction force of the driving feet of the first driving unit and the second driving unit ₁ ；

If the output shaft needs to be driven to move reversely:

step A.2.2), driving the third piezoelectric element and the second piezoelectric element T for 1 second simultaneously by using ascending triangular waves in the first and second driving units, and moving the third piezoelectric element and the second piezoelectric element to an elongated shapeIn a state, the motion blocks of the first driving unit and the second driving unit are pushed to simultaneously generate reverse motion, and at the moment, the output shaft generates reverse displacement x under the action of static friction force of the driving feet of the first driving unit and the second driving unit ₁ ；

Step B), as shown in fig. 5, the first driving unit and the second driving unit adopt triangular waves to alternately drive:

if it is required to drive the output shaft in the forward direction:

step B.1.2), in an initial state, the first piezoelectric component and the second piezoelectric component in the second driving unit are in an elongation state; at 0 to t ₁ In seconds, the first driving unit drives the first piezoelectric component and the second piezoelectric component by ascending triangular waves, the first piezoelectric component and the second piezoelectric component in the first driving unit move to an elongation state, and the motion block of the first driving unit is pushed to generate forward motion; meanwhile, the descending triangular wave is adopted to drive the first piezoelectric component and the second piezoelectric component in the second driving unit, the first piezoelectric component and the second piezoelectric component in the second driving unit move to a contracted state, the moving block of the second driving unit is pulled to generate reverse movement, and at the moment, the forward movement generated by the moving block of the first driving unit is smaller than the reverse movement generated by the moving block of the second driving unit, so that the common friction force of the output shaft on the driving feet of the first driving unit and the second driving unit Under the action of the reverse displacement x ₁ ；

Step B.1.4), at t ₂ To t ₃ In seconds, the first piezoelectric component and the second piezoelectric component in the first driving unit are driven by descending triangular waves, the first piezoelectric component and the second piezoelectric component in the first driving unit move to a contracted state, and a motion block of the first driving unit is pulled to generate reverse motion; meanwhile, the ascending triangular wave is adopted to drive a first piezoelectric component and a second piezoelectric component in a second driving unit, the first piezoelectric component and the second piezoelectric component in the second driving unit move to an elongation state, and a motion block of the second driving unit is pushed to generate forward motion; because the reverse motion generated by the motion block of the first driving unit is smaller than the forward motion generated by the motion block of the second driving unit, the output shaft generates forward displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit ₃ ；

If the output shaft needs to be driven to move reversely:

step B.2.2), in an initial state, the third piezoelectric component and the second piezoelectric component in the second driving unit are in an elongation state; at 0 to t ₁ In seconds, the first driving unit drives the third piezoelectric component and the second piezoelectric component by rising triangular waveThe third piezoelectric component and the second piezoelectric component in the first driving unit move to an elongation state to push the moving block of the first driving unit to generate reverse movement; meanwhile, the descending triangular wave is adopted to drive a third piezoelectric component and a second piezoelectric component in a second driving unit, the third piezoelectric component and the second piezoelectric component in the second driving unit move to a contracted state, a moving block of the second driving unit is pulled to generate forward movement, and at the moment, the reverse movement generated by the moving block of the first driving unit is smaller than the forward movement generated by the moving block of the second driving unit, so that an output shaft generates forward displacement x under the action of the common friction force of driving feet of the first driving unit and the second driving unit ₁ ；

Step B.2.3), at t ₁ To t ₂ In seconds, the ascending triangular wave is adopted to drive the third piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit simultaneously, the third piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit move to an extension state, the moving blocks of the first driving unit and the second driving unit are pushed to synchronously generate reverse movement, and the output shaft generates reverse displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit ₂ ；

Step b.2.5), repeating steps b.2.2) to b.2.4), so that the output is performedForward motion of the output shaft step by step, and the step length of each period is x ₂ +x ₃ -x ₁ 。

step a), as shown in fig. 6, the first driving unit and the second driving unit adopt sine waves to perform synchronous driving:

step A.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component in the first driving unit and the second driving unit moves to an extension state, the third piezoelectric component moves to a contraction state and the second piezoelectric component contracts to an original length state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate forward movement, and the output shaft acts on the common friction force of the driving feet of the first driving unit and the second driving unitGenerating a positive displacement x;

Step A.1.5), at t ₃ To t ₄ In seconds, the first piezoelectric component in the first driving unit and the second driving unit moves to a contracted state, the third piezoelectric component moves to an extended state, and the second piezoelectric component extends to an original length state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate reverse movement, and the output shaft is static because the output shaft is not contacted with the driving feet of the first driving unit and the second driving unit in the process;

at 0 to t ₁ In seconds, the third piezoelectric component in the first and second driving units stretches to the original length state, and the first piezoelectric componentThe piece is contracted to an original length state, the second piezoelectric component moves to an extension state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate reverse movement, and the output shaft generates reverse displacement x under the action of the common friction force of the driving feet of the first driving unit and the second driving unit;

step A.2.4), at t ₂ To t ₃ In seconds, the third piezoelectric component in the first and second driving units contracts to an original length state, the first piezoelectric component extends to the original length state, and the second piezoelectric component moves to the contracted state, so that the moving blocks of the first and second driving units simultaneously generate forward movement, and the output shaft is static because the output shaft is not contacted with the driving feet of the first and second driving units in the process;

step B), as shown in fig. 7, the first driving unit and the second driving unit adopt sine waves to alternately drive:

if it is required to drive the output shaft in the forward direction:

step B.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component in the first driving unit moves to an extension state, the third piezoelectric component moves to a contraction state and the second piezoelectric component contracts to an original length state, so that the motion block in the first driving unit generates forward motion, the first piezoelectric component in the second driving unit moves to the contraction state, the third piezoelectric component moves to the extension state and the second piezoelectric component extends to the original length state, and the motion block in the second driving unit generates Generating reverse motion, wherein the output shaft generates forward motion displacement x under the action of friction force of a driving foot in the first driving unit;

step B.1.5), at t ₃ To t ₄ In second, the first piezoelectric component in the first driving unit moves to a contracted state, the third piezoelectric component moves to an extended state, the second piezoelectric component extends to an original length state, the motion block in the first driving unit moves to an extended state, the third piezoelectric component moves to the contracted state, the second piezoelectric component contracts to the original length state, the motion block in the second driving unit generates forward motion, and the output shaft generates forward motion displacement x under the action of the friction force of the driving foot in the second driving unit;

if the output shaft needs to be driven to move reversely:

At 0 to t ₁ In seconds, a third piezoelectric component in the first driving unit stretches to an original length state, the first piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an stretching state, so that a motion block in the first driving unit generates reverse motion, the third piezoelectric component in the second driving unit contracts to an original length state, the first piezoelectric component stretches to an original length state, and the second piezoelectric component moves to a contraction state, so that a motion block in the second driving unit generates forward motion, and an output shaft generates reverse motion displacement x under the action of friction force of a driving foot in the first driving unit;

Step B.2.4), at t ₂ To t ₃ In seconds, the third piezoelectric component in the first driving unit contracts to an original length state, the first piezoelectric component extends to the original length state, and the second piezoelectric component moves to the contracted state, so that a moving block in the first driving unit generatesThe third piezoelectric component in the second driving unit stretches to an original length state, the first piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an stretching state, so that the motion block in the second driving unit generates reverse motion, and the output shaft generates reverse motion displacement x under the action of friction force of the driving foot in the second driving unit;

step B.2.5), at t ₃ To t ₄ In second, the third piezoelectric component in the first driving unit moves to a contracted state, the first piezoelectric component moves to an extended state, and the second piezoelectric component extends to an original length state, so that the motion block in the first driving unit generates forward motion, the third piezoelectric component in the second driving unit moves to an extended state, the first piezoelectric component moves to a contracted state, and the second piezoelectric component contracts to an original length state, the motion block in the second driving unit generates reverse motion, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving foot in the second driving unit;

step A), as shown in FIG. 8, the first driving unit and the second driving unit adopt trapezoidal waves for synchronous driving:

if the driving action shaft is required to move in the forward direction:

at 0 to t ₁ In second, the second piezoelectric component is driven by the rising ramp wave in the first and second driving units and the voltage of the third piezoelectric component is kept unchanged, the first and second driving unitsThe second piezoelectric component moves to an extension state, the third piezoelectric component keeps the extension state unchanged, the motion blocks of the first driving unit and the second driving unit are pushed to be close to the output shaft at the same time, and the driving foot is propped against the output shaft;

if necessary, driving the motion shaft to move reversely:

step A.2.3), at t ₁ To t ₂ In seconds, the third piezoelectric component is driven by ascending oblique waves in the first driving unit and the second driving unit, the first piezoelectric component is driven by descending oblique waves and the voltage of the second piezoelectric component is kept unchanged, the third piezoelectric component of the first driving unit and the second driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged in the extension state, so that the motion blocks of the first driving unit and the second driving unit generate reverse motion, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving feet in the first driving unit and the second driving unit;

step A.2.5), at t ₃ To t ₄ In seconds, the first piezoelectric component is driven by ascending oblique waves in the first driving unit and the second driving unit, the third piezoelectric component is driven by descending oblique waves in the first driving unit and the second driving unit, the first piezoelectric component of the first driving unit and the second driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the moving blocks of the first driving unit and the second driving unit generate forward movement, and the output shaft is not connected with the first driving unit,The driving foot of the second driving unit is contacted, so that the output shaft is stationary;

step B), as shown in fig. 9, the first driving unit and the second driving unit alternately drive by using trapezoidal waves:

if it is required to drive the output shaft in the forward direction:

step B.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component of the first driving unit is driven by the ascending ramp wave, the third piezoelectric component is driven by the descending ramp wave, the voltage of the second piezoelectric component of the first driving unit is kept unchanged, the first piezoelectric component of the first driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged, the moving block of the first driving unit generates forward movement, the third piezoelectric component is driven by the ascending ramp wave in the second driving unit, the first piezoelectric component is driven by the descending ramp wave, and the second driving unit The third piezoelectric component of the element moves to an extension state, the first piezoelectric component contracts to an original length state, the motion block of the second driving unit moves reversely, and the output shaft generates forward motion displacement x under the action of the friction force of the driving foot in the first driving unit;

step B.1.4), at t ₂ To t ₃ In seconds, a descending oblique wave is adopted in the first driving unit to drive the second piezoelectric component, the voltage of the first piezoelectric component is kept unchanged, the second piezoelectric component of the first driving unit is contracted to an original length state, the first piezoelectric component is kept unchanged in an extension state, the moving block of the first driving unit is pulled to be far away from the output shaft at the same time, an ascending oblique wave is adopted in the second driving unit to drive the second piezoelectric component, the voltage of the third piezoelectric component is kept unchanged, the second piezoelectric component of the second driving unit is moved to an extension state, the third piezoelectric component is kept unchanged in an extension state, and the moving block of the second driving unit is pushed to be close to the output shaft;

if the output shaft needs to be driven to move reversely:

at 0 to t ₁ In seconds, driving the second piezoelectric component by using an ascending oblique wave in the first driving unit, keeping the voltage of the first piezoelectric component unchanged, enabling the second piezoelectric component of the first driving unit to move to an extension state, keeping the extension state of the first piezoelectric component unchanged, pushing the moving block of the first driving unit to be close to the output shaft, driving the second piezoelectric component by using a descending oblique wave in the second driving unit, keeping the voltage of the third piezoelectric component unchanged, enabling the second piezoelectric component of the second driving unit to shrink to an original length state, keeping the extension state of the third piezoelectric component unchanged, and pulling the moving block of the second driving unit to be simultaneously far away from the output shaft;

step B.2.4), at t ₂ To t ₃ In second, the second piezoelectric component is driven by the descending ramp wave in the first driving unit and the voltage of the third piezoelectric component is kept unchanged, the second piezoelectric component of the first driving unit is contracted to the original length state, and the third piezoelectric component is kept stretchedThe long state is unchanged, the motion block of the first driving unit is pulled to be far away from the output shaft, the second driving unit adopts ascending oblique waves to drive the second piezoelectric component and keep the voltage of the first piezoelectric component unchanged, the second piezoelectric component of the second driving unit moves to an extension state, the first piezoelectric component keeps the extension state unchanged, and the motion block of the second driving unit is pushed to be close to the output shaft;

Step B.2.5), at t ₁ To t ₂ In seconds, the first piezoelectric component is driven by the rising oblique wave in the first driving unit, the third piezoelectric component is driven by the falling oblique wave, the first piezoelectric component of the first driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the motion block of the first driving unit moves forwards, the third piezoelectric component is driven by the rising oblique wave in the second driving unit, the first piezoelectric component is driven by the falling oblique wave, the voltage of the second piezoelectric component is kept unchanged, the third piezoelectric component of the second driving unit moves to an extension state, the first piezoelectric component contracts to the original length state, the second piezoelectric component is kept unchanged, the motion block of the second driving unit moves reversely, and the output shaft generates reverse motion displacement x under the action of the friction force of the driving foot in the second driving unit;

It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

While the foregoing is directed to embodiments of the present invention, other and further details of the invention may be had by the present invention, it should be understood that the foregoing description is merely illustrative of the present invention and that no limitations are intended to the scope of the invention, except insofar as modifications, equivalents, improvements or modifications are within the spirit and principles of the invention.

Claims

1. The multi-mode linear piezoelectric driver based on the flexible hinge structure is characterized by comprising a shell, an output shaft, a pre-tightening bolt and a driving module;

2. The multi-mode linear piezoelectric actuator based on a flexible hinge structure according to claim 1, wherein a friction layer made of ceramic material is provided on a side wall of the output shaft which abuts against the driving feet of the first and second driving units.

3. The working method of the multimode linear piezoelectric driver based on the flexible hinge structure as claimed in claim 1, wherein the first driving unit and the second driving unit adopt triangular waves for driving:

if it is required to drive the output shaft in the forward direction:

step A.2.1.2), driving the first piezoelectric component and the second piezoelectric component T for 1 second in the first driving unit and the second driving unit by ascending triangular waves, enabling the first piezoelectric component and the second piezoelectric component to move to an elongation state, pushing the moving blocks of the first driving unit and the second driving unit to simultaneously generate forward movement, and enabling the output shaft to generate forward displacement under the action of static friction force of the driving feet of the first driving unit and the second driving unitx ₁ ；

Step A.2.1.3), driving the first piezoelectric component and the second piezoelectric component for T2 seconds by adopting descending triangular waves in the first driving unit and the second driving unit, wherein T2 is smaller than T1, the first piezoelectric component and the second piezoelectric component move to a contracted state, and the moving blocks of the first driving unit and the second driving unit are pulled to simultaneously generate reverse movement, thereby realizing the purposes of high-speed vibration and high-speed vibrationWhen the output shaft is subjected to the sliding friction force of the driving feet of the first driving unit and the second driving unit, the output shaft generates reverse displacementx ₂ ；

Step a.2.1.4), repeating steps a.2.1.2) through a.2.1.3) such that the output shaft moves in a stepwise forward direction, each cycle having a step length of x ₁ -x ₂ ；

If the output shaft needs to be driven to move reversely:

step A.2.2), driving the third piezoelectric component and the second piezoelectric component T for 1 second in the first driving unit and the second driving unit by ascending triangular wave, enabling the third piezoelectric component and the second piezoelectric component to move to an elongation state, pushing the moving blocks of the first driving unit and the second driving unit to simultaneously generate reverse movement, and enabling the output shaft to generate reverse displacement under the static friction force of the driving feet of the first driving unit and the second driving unit at the momentx ₁ ；

Step A.2.3), driving the third piezoelectric component and the second piezoelectric component in the first and second driving units by adopting descending triangular waves for 2 seconds, wherein T2 is smaller than T1, the third piezoelectric component and the second piezoelectric component move to a shortened state, the moving blocks of the first and second driving units are pulled to simultaneously generate forward movement, and at the moment, the output shaft generates forward displacement under the action of sliding friction force of the driving feet of the first and second driving unitsx ₂ ；

Step a.2.4), repeating steps a.2.2) to a.2.3), so that the output shaft moves in a step-by-step reverse direction, and the step length of each period is as follows x ₁ -x ₂ ；

if it is required to drive the output shaft in the forward direction:

step B.1.2In the initial state, the first piezoelectric component and the second piezoelectric component in the second driving unit are in an extension state; at 0 to t ₁ In seconds, the first driving unit drives the first piezoelectric component and the second piezoelectric component by ascending triangular waves, the first piezoelectric component and the second piezoelectric component in the first driving unit move to an elongation state, and the motion block of the first driving unit is pushed to generate forward motion; meanwhile, the descending triangular wave is adopted to drive the first piezoelectric component and the second piezoelectric component in the second driving unit, the first piezoelectric component and the second piezoelectric component in the second driving unit move to a contracted state, the moving block of the second driving unit is pulled to generate reverse movement, and at the moment, the forward movement generated by the moving block of the first driving unit is smaller than the reverse movement generated by the moving block of the second driving unit, so that the output shaft generates reverse displacement under the action of the common friction force of the driving feet of the first driving unit and the second driving unit x ₁ ；

Step B.1.3), at t ₁ To t ₂ In seconds, the ascending triangular wave is adopted to drive the first piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit simultaneously, the first piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit move to an extension state, the moving blocks of the first driving unit and the second driving unit are pushed to simultaneously generate forward movement, and the output shaft generates forward displacement under the action of the common friction force of the driving feet of the first driving unit and the second driving unitx ₂ ；

Step B.1.4), at t ₂ To t ₃ In seconds, the first piezoelectric component and the second piezoelectric component in the first driving unit are driven by descending triangular waves, the first piezoelectric component and the second piezoelectric component in the first driving unit move to a contracted state, and a motion block of the first driving unit is pulled to generate reverse motion; meanwhile, the ascending triangular wave is adopted to drive a first piezoelectric component and a second piezoelectric component in a second driving unit, the first piezoelectric component and the second piezoelectric component in the second driving unit move to an elongation state, and a motion block of the second driving unit is pushed to generate forward motion; the reverse motion generated by the motion block of the first driving unit is smaller than the positive motion generated by the motion block of the second driving unit To move in the forward direction, so that the output shaft generates positive displacement under the action of the common friction force of the driving feet of the first and second driving unitsx ₃ ；

Step b.1.5), repeating steps b.1.2) through b.1.4) such that the output shaft moves in a stepwise forward direction, each cycle having a step length ofx ₂ +x ₃ - x ₁ ；

If the output shaft needs to be driven to move reversely:

step B.2.2), in an initial state, the third piezoelectric component and the second piezoelectric component in the second driving unit are in an elongation state; at 0 to t ₁ In second, the third piezoelectric component and the second piezoelectric component are driven by ascending triangular waves in the first driving unit, and the third piezoelectric component and the second piezoelectric component in the first driving unit move to an elongation state to push the moving block of the first driving unit to generate reverse movement; meanwhile, the descending triangular wave is adopted to drive a third piezoelectric component and a second piezoelectric component in the second driving unit, the third piezoelectric component and the second piezoelectric component in the second driving unit move to a contracted state, the moving block of the second driving unit is pulled to generate forward movement, and at the moment, the reverse movement generated by the moving block of the first driving unit is smaller than the forward movement generated by the moving block of the second driving unit, so that the output shaft generates forward displacement under the action of the common friction force of the driving feet of the first driving unit and the second driving unit x ₁ ；

Step B.2.3), at t ₁ To t ₂ In seconds, the ascending triangular wave is adopted to drive the third piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit simultaneously, the third piezoelectric component and the second piezoelectric component in the first driving unit and the second driving unit move to an extension state, the moving blocks of the first driving unit and the second driving unit are pushed to synchronously generate reverse movement, and the output shaft generates reverse displacement under the action of the common friction force of the driving feet of the first driving unit and the second driving unitx ₂ ；

Step B.2.4), at t ₂ To t ₃ In seconds, the descending triangular wave is adopted to drive a third piezoelectric component and a second piezoelectric component in the first driving unit, the third piezoelectric component and the second piezoelectric component in the first driving unit move to a contracted state, and a motion block of the first driving unit is pulled to generate forward motion; meanwhile, the ascending triangular wave is adopted to drive a third piezoelectric component and a second piezoelectric component in the second driving unit, the third piezoelectric component and the second piezoelectric component in the second driving unit move to an elongation state, and a motion block of the second driving unit is pushed to generate reverse motion; because the forward motion generated by the motion block of the first driving unit is smaller than the backward motion generated by the motion block of the second driving unit, the output shaft generates backward displacement under the action of the common friction force of the driving feet of the first driving unit and the second driving unit x ₃ ；

Step b.2.5), repeating steps b.2.2) through b.2.4) such that the output shaft moves in a stepwise forward direction, each cycle having a step length ofx ₂ +x ₃ - x ₁ 。

4. The working method of the multimode linear piezoelectric driver based on the flexible hinge structure as claimed in claim 1, wherein the first driving unit and the second driving unit adopt sine waves for driving:

At 0 to t ₁ In seconds, the first piezoelectric component in the first driving unit and the second driving unit stretches to an original length state, the third piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an stretching state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate forward movement, and the output shaft generates forward displacement under the action of the common friction force of the driving feet of the first driving unit and the second driving unitx；

Step A.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component in the first driving unit and the second driving unit moves to an extension state, the third piezoelectric component moves to a contraction state and the second piezoelectric component contracts to an original length state, so that the moving blocks of the first driving unit and the second driving unit simultaneously generate forward movement, and the output shaft generates forward displacement under the action of the common friction force of the driving feet of the first driving unit and the second driving unitx；

step A.1.6), repeating steps A.1.2) to A.1.5), so that the first and second drivesThe driving foot of the moving unit generates elliptical motion, the output shaft performs stepping forward motion, and the motion length of each period is 2x；

at 0 to t ₁ In seconds, the third piezoelectric component in the first and second driving units stretches to the original length state, the first piezoelectric component contracts to the original length state, and the second piezoelectric component moves to the stretching state, so that the moving blocks of the first and second driving units simultaneously generate reverse movement, and the output shaft generates reverse displacement under the action of the common friction force of the driving feet of the first and second driving unitsx；

Step A.2.3), at t ₁ To t ₂ In seconds, the third piezoelectric component in the first and second driving units moves to an extension state, the first piezoelectric component moves to a contraction state, and the second piezoelectric component contracts to an original length state, so that the moving blocks of the first and second driving units simultaneously generate reverse movement, and the output shaft generates reverse displacement under the action of the common friction force of the driving feet of the first and second driving unitsx；

Step A.2.4), at t ₂ To t ₃ In seconds, the third piezoelectric component in the first and second driving units contracts to the original length state, the first piezoelectric component extends to the original length state, and the second piezoelectric component moves to the contracted state, so that the moving blocks of the first and second driving units simultaneously generate forward movement The output shaft is static because the output shaft is not contacted with the driving feet of the first driving unit and the second driving unit in the process;

step A.2.6), repeating the steps A.2.2) to A.2.5), so that the driving feet of the first driving unit and the second driving unit generate elliptical motion, the output shaft performs stepping reverse motion, and the motion length of each period is 2x；

if it is required to drive the output shaft in the forward direction:

at 0 to t ₁ In seconds, the first piezoelectric component in the first driving unit stretches to an original length state, the third piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an stretching state, so that the motion block in the first driving unit generates forward motion, the first piezoelectric component in the second driving unit contracts to an original length state, the third piezoelectric component stretches to an original length state, and the second piezoelectric component moves to a contracted state, so that the motion block in the second driving unit generates reverse motion, and the output shaft generates forward motion displacement under the action of the friction force of the driving foot of the first driving unitx；

Step B.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component in the first driving unit moves to an extension state, the third piezoelectric component moves to a contraction state and the second piezoelectric component contracts to an original length state, so that the motion block in the first driving unit generates forward motion, the first piezoelectric component in the second driving unit moves to the contraction state, the third piezoelectric component moves to the extension state and the second piezoelectric component extends to the original length state, the motion block in the second driving unit generates reverse motion, and the output shaft generates forward motion displacement under the action of the friction force of the driving foot in the first driving unit x；

Step B.1.4), at t ₂ To t ₃ In seconds, the first piezoelectric component in the first driving unit contracts to an original length state, the third piezoelectric component contracts to an original length state, and the second piezoelectric component moves to a contracted state, so that the motion block in the first driving unit generates reverse motion, the first piezoelectric component in the second driving unit extends to an original length state, the third piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an extended state, so that the motion block in the second driving unit generates forward motion, and the output shaft generates forward motion displacement under the action of the friction force of the driving foot in the second driving unitx；

Step B.1.5), at t ₃ To t ₄ In seconds, the first piezoelectric component in the first driving unit moves to a contracted state, the third piezoelectric component moves to an extended state, the second piezoelectric component extends to an original length state, and the moving block in the first driving unit is caused to moveThe first piezoelectric component in the second driving unit moves to an extension state, the third piezoelectric component moves to a contraction state, the second piezoelectric component contracts to an original length state, the moving block in the second driving unit moves forward, and the output shaft generates forward movement displacement under the action of friction force of the driving foot in the second driving unit x；

Step B.1.6), repeating the steps B.1.2) to B.1.5), so that the driving feet of the first driving unit and the second driving unit generate elliptical motion, the output shaft continuously moves in the forward direction, and the motion length of each period is 4x；

If the output shaft needs to be driven to move reversely:

At 0 to t ₁ In seconds, the third piezoelectric component in the first driving unit stretches to an original length state, the first piezoelectric component contracts to an original length state, and the second piezoelectric component moves to an stretching state, so that the motion block in the first driving unit moves reversely, and the third piezoelectric component in the second driving unit contracts to an original length stateThe first piezoelectric component extends to an original length state, the second piezoelectric component moves to a contracted state, the motion block in the second driving unit generates forward motion, and the output shaft generates reverse motion displacement under the action of friction force of the driving foot in the first driving unitx；

Step B.2.3), at t ₁ To t ₂ In seconds, the third piezoelectric component in the first driving unit moves to an extension state, the first piezoelectric component moves to a contraction state, and the second piezoelectric component contracts to an original length state, so that the motion block in the first driving unit moves reversely, the third piezoelectric component in the second driving unit moves to the contraction state, the first piezoelectric component moves to the extension state, and the second piezoelectric component extends to the original length state, so that the motion block in the second driving unit moves positively, and the output shaft generates reverse motion displacement under the action of the friction force of the driving foot in the first driving unit x；

Step B.2.4), at t ₂ To t ₃ In seconds, the third piezoelectric component in the first driving unit contracts to an original length state, the first piezoelectric component extends to an original length state, the second piezoelectric component moves to a contracted state, so that the moving block in the first driving unit generates forward movement, the third piezoelectric component in the second driving unit extends to an original length state, the first piezoelectric component contracts to an original length state, the second piezoelectric component moves to an extended state, the moving block in the second driving unit generates reverse movement, and the output shaft generates reverse movement displacement under the action of the friction force of the driving foot in the second driving unitx；

Step B.2.5), at t ₃ To t ₄ In seconds, the third piezoelectric component in the first driving unit moves to a contracted state, the first piezoelectric component moves to an extended state, and the second piezoelectric component extends to an original length state, so that the moving block in the first driving unit generates forward movement, the third piezoelectric component in the second driving unit moves to an extended state, the first piezoelectric component moves to a contracted state, and the second piezoelectric component contracts to an original length state, so that the moving block in the second driving unit generates reverse movement, and the output shaft generates reverse movement displacement under the action of the friction force of the driving foot in the second driving unit x；

Step B.2.6), repeating the steps B.2.2) to B.2.5), so that the driving feet of the first driving unit and the second driving unit generate elliptical motion, the output shaft continuously moves reversely, and the motion length of each period is 4x。

5. The working method of the multimode linear piezoelectric driver based on the flexible hinge structure as claimed in claim 1, wherein the first driving unit and the second driving unit are driven by trapezoidal waves:

if the driving action shaft is required to move in the forward direction:

Step A.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component is driven by ascending oblique waves in the first driving unit and the second driving unit, the third piezoelectric component is driven by descending oblique waves and the voltage of the second piezoelectric component is kept unchanged, the first piezoelectric component of the first driving unit and the second driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged in the extension state, the moving blocks of the first driving unit and the second driving unit generate forward movement, and the output shaft generates forward movement displacement under the action of friction force of driving feet in the first driving unit and the second driving unitx；

Step a.1.6), repeating steps a.1.2) through a.1.5), such that the output shaft moves in a stepwise forward direction, each cycle having a step length ofx；

If necessary, driving the motion shaft to move reversely:

step A.2.3), at t ₁ To t ₂ In seconds, the first and second driving units simultaneously drive the third piezoelectric component by using ascending oblique waves and simultaneously drive the first piezoelectric component by using descending oblique wavesThe voltage of the second piezoelectric component is kept unchanged, the third piezoelectric component of the first and second driving units moves to an extension state, the first piezoelectric component contracts to an original length state, the second piezoelectric component keeps unchanged in the extension state, the moving blocks of the first and second driving units move reversely, and the output shaft generates reverse movement displacement under the action of friction force of the driving feet in the first and second driving units x；

step a.2.6), repeating steps a.2.2) to a.2.5), such that the output shaft steps in reverse motion, each cycle having a step length ofx；

if it is required to drive the output shaft in the forward direction:

step B.1.3), at t ₁ To t ₂ In seconds, the first piezoelectric component is driven by the rising oblique wave in the first driving unit, the third piezoelectric component is driven by the falling oblique wave and the voltage of the second piezoelectric component of the first driving unit is kept unchanged, the first piezoelectric component of the first driving unit moves to an extension state, the third piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged in extension state, the moving block of the first driving unit generates forward movement, the third piezoelectric component is driven by the rising oblique wave in the second driving unit and the first piezoelectric component is driven by the falling oblique wave, the third piezoelectric component of the second driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the moving block of the second driving unit generates reverse movement, and the output shaft generates forward movement displacement under the action of friction force of the driving foot in the first driving unit x；

Step B.1.4), at t ₂ To t ₃ In second, the second piezoelectric component is driven by the descending oblique wave in the first driving unit, the voltage of the first piezoelectric component is kept unchanged, the second piezoelectric component of the first driving unit is contracted to an original length state, the first piezoelectric component is kept unchanged in an extension state, the moving block of the first driving unit is pulled to be far away from the output shaft, the second piezoelectric component is driven by the ascending oblique wave in the second driving unit, the voltage of the third piezoelectric component is kept unchanged, the second piezoelectric component of the second driving unit is moved to an extension state, the third piezoelectric component is kept unchanged in an extension state,pushing the motion block of the second driving unit to be close to the output shaft;

step B.1.5), at t ₁ To t ₂ In seconds, the third piezoelectric component is driven by the rising ramp wave and the first piezoelectric component is driven by the falling ramp wave in the first driving unit, the third piezoelectric component of the first driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the motion block of the first driving unit moves reversely, the first piezoelectric component is driven by the rising ramp wave and the third piezoelectric component is driven by the falling ramp wave in the second driving unit, meanwhile, the voltage of the second piezoelectric component of the second driving unit is kept unchanged, the first piezoelectric component of the second driving unit moves to the extension state, the third piezoelectric component contracts to the original length state, the second piezoelectric component is kept unchanged, the motion block of the second driving unit moves positively, and the output shaft generates forward motion displacement under the action of friction force of the driving foot in the second driving unit x；

Step b.1.6), repeating steps b.1.2) to b.1.5) such that the output shaft moves in a stepwise forward direction, each cycle having a step length of 2x；

If the output shaft needs to be driven to move reversely:

at 0 to t ₁ In seconds, the second piezoelectric component is driven by the ascending ramp wave in the first driving unit, the voltage of the first piezoelectric component is kept unchanged, the second piezoelectric component of the first driving unit moves to an extension state, the first piezoelectric component is kept unchanged, the moving block of the first driving unit is pushed to be close to the output shaft, the second piezoelectric component is driven by the descending ramp wave in the second driving unit, the voltage of the third piezoelectric component is kept unchanged, and the second piezoelectric component of the second driving unit contracts to be in an original long shapeThe state and the third piezoelectric component keep the extension state unchanged, and the motion block of the second driving unit is pulled to be far away from the output shaft;

Step B.2.3), at t ₁ To t ₂ In seconds, the third piezoelectric component is driven by the ascending oblique wave in the first driving unit, the first piezoelectric component is driven by the descending oblique wave and the voltage of the second piezoelectric component is kept unchanged, the third piezoelectric component of the first driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged in the extension state, the moving block of the first driving unit moves reversely, the first piezoelectric component is driven by the ascending oblique wave in the second driving unit and the third piezoelectric component is driven by the descending oblique wave, the first piezoelectric component of the second driving unit moves to the extension state, the third piezoelectric component contracts to the original length state, the moving block of the second driving unit moves positively, and the output shaft generates reverse movement displacement under the action of the friction force of the driving foot in the first driving unitx；

Step B.2.5), at t ₁ To t ₂ In second, the first piezoelectric component is driven by the ascending ramp wave in the first driving unit and the third piezoelectric component is driven by the descending ramp wave, the first piezoelectric component of the first driving unit moves to an extending state, the third piezoelectric component contracts to an original length state, the moving block of the first driving unit generates forward movement, the third piezoelectric component is driven by the ascending ramp wave in the second driving unit, and the third piezoelectric component is driven by the descending ramp waveThe first piezoelectric component is driven by the oblique wave of the second driving unit, the voltage of the second piezoelectric component is kept unchanged, the third piezoelectric component of the second driving unit moves to an extension state, the first piezoelectric component contracts to an original length state, the second piezoelectric component is kept unchanged in the extension state, the motion block of the second driving unit generates reverse motion, and the output shaft generates reverse motion displacement under the action of the friction force of the driving foot in the second driving unitx；

Step b.2.6), repeating steps b.2.2) to b.2.5) such that the output shaft is stepped in a reverse direction, the step length of each cycle being 2x。