CN105827141B - Inclined ladder shape moves change type precision piezoelectricity stick-slip line motor and its driving method - Google Patents

Abstract

A precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion and a driving method thereof, to solve the problems of limited output mechanical performance of the current piezoelectric stick-slip linear motor due to the difficulty in comprehensive control of friction force. The invention consists of four parts: a base, a pre-pressure adjusting device, an oblique trapezoidal stator and a mover. The stator uses a symmetrical flexible hinge structure to generate displacement amplification, and utilizes an oblique trapezoidal drive foot to generate uneven axial stiffness distribution to generate lateral Displacement increases the frictional driving force and reduces frictional resistance; at the same time, the friction control wave is compounded and superimposed on the sawtooth driving wave in the rapid deformation stage of the stator, thereby reducing the frictional resistance between the stator and the mover in the rapid deformation stage, and realizing the synthesis of frictional force Regulating, significantly improving the mechanical output characteristics of the linear piezoelectric motor. The invention has the characteristics of simple structure, high precision, large stroke, etc., and has good application prospects in the fields of micro-nano precision driving and positioning such as aerospace, optical precision instruments, and semiconductor processing.

Description

Inclined trapezoidal motion conversion precision piezoelectric stick-slip linear motor and its driving method

technical field

The invention relates to an oblique trapezoidal motion conversion precision piezoelectric stick-slip linear motor and a driving method thereof, belonging to the technical field of micro-nano precision driving and positioning.

Background technique

Piezoelectric stick-slip linear motor is a kind of piezoelectric stick-slip linear motor that uses the inverse piezoelectric effect of piezoelectric elements to excite the vibrator (or stator) to generate micro-vibration under the excitation of an asymmetric electrical signal, and realizes mechanical energy output through the frictional coupling between the vibrator and the mover. precision micro-nano actuators. According to different driving working principles, piezoelectric stick-slip linear motors are mainly divided into two categories: resonant piezoelectric motors (also called ultrasonic motors) and non-resonant piezoelectric motors (also called piezoelectric stick-slip motors). Compared with the resonant piezoelectric motor, the piezoelectric stick-slip linear motor has the advantages of simple and compact structure, high positioning accuracy, and convenient control, and is widely used in the technical field of precision driving and positioning.

Piezoelectric stick-slip driving is mainly to apply the sawtooth excitation electric signal to the piezoelectric element to excite the stator to produce alternating fast and slow motion deformation, and to control the mutual conversion between the stator and the mover between the two motion states of "sticky" and "slip". The friction drives the mover to realize mechanical motion output. However, due to the slow and fast deformation stages of piezoelectric stick-slip driving, the friction force between the stator and the mover plays different roles, specifically, it is frictional driving force in the slow deformation driving stage, and friction resistance in the rapid deformation driving stage. Existing published technologies have shown that the current piezoelectric stick-slip linear motor cannot comprehensively regulate the friction force during the entire driving process, resulting in limited output mechanical properties. Especially in the rapid deformation driving stage of the stator, since the frictional force on the mover is opposite to its motion direction, when the inertial force of the mover is not enough to overcome the frictional resistance, the mover will produce a retreat motion, which appears as a sawtooth-like Unstable motion output and degraded output performance. The existing sawtooth excitation electrical signal cannot realize the regulation of the friction force in the rapid deformation driving stage of the piezoelectric stick-slip linear motor, which further limits the application and development of the piezoelectric stick-slip linear motor.

Contents of the invention

In order to solve the technical problems of the existing piezoelectric stick-slip linear motors, such as the difficulty in comprehensive regulation of the friction force between the stator and the mover, the limited output mechanical performance, the generation of sawtooth-like unstable motion output, and the degradation of output performance, the present invention discloses A precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion and its driving method are presented.

The technical scheme adopted in the present invention is:

The described precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion is composed of a base, a pre-pressure adjustment device, an inclined trapezoidal stator and a mover.

The base includes a base installation hole, a pre-pressure device installation hole, a guide rail fixed installation contact surface and a guide rail threaded installation hole. The mounting hole of the base can fix the base and other peripheral devices, the mounting hole of the pre-pressure adjusting device is used for fixing the pre-pressure adjusting device, the fixed mounting contact surface of the guide rail and the threaded mounting hole of the guide rail are used for installing the mover.

The pre-pressure adjusting device includes a lower fixed slide table, an upper movable slide table, a pretightening force manual adjustment screw and a platform locking screw. The lower fixed slide is provided with a threaded hole for threaded connection with the pre-tightening force manual adjustment screw, the lower fixed slide is provided with a spring fixed cylinder for installing a pre-compressed spring, and the lower fixed slide is provided with a guide rail It is used for the movement of the upper movable sliding table. The guide rail is provided with guide rail limit screws to prevent the upper movable sliding table from exceeding the stroke of the guide rail. The fixed installation of the lower fixed sliding table is provided with a locking support frame and a locking support frame fixing screw, and the locking of the upper movable sliding table can be realized by adjusting the platform locking screw. The upper end surface of the upper movable sliding table is provided with threaded holes for installing the inclined trapezoidal stator, and the upper movable sliding table is provided with mounting holes for platform locking screws to be threadedly connected with the platform locking screws.

The inclined trapezoidal stator includes a frame-shaped hinge, a piezoelectric stack, a pre-tightening bolt and an adjusting gasket. The hinge of the frame-shaped structure adopts a flexible hinge of symmetrical rectangular structure, and the hinge of the frame-shaped structure is provided with a fastening bolt installation hole, and the hinge of the frame-shaped structure is screwed to the threaded hole on the upper movable sliding table through the bolt. Fixed connection. The right side of the hinge of the frame structure is provided with 2 right straight round flexible hinges, and the left side is provided with 2 left straight round flexible hinges, the 2 right straight round flexible hinges and 2 left straight round flexible hinges Type flexible hinges are connected by rigid beams, specifically, two right straight round flexible hinges are connected by rigid beams, two left straight round flexible hinges are connected by rigid beams, and right straight round flexible hinges and left straight round flexible hinges are connected by rigid beams. Type flexible hinges are also connected through rigid beams. The hinges of the frame structure are provided with inclined trapezoidal stator driving feet. The piezoelectric stack is fixed and installed on the hinges of the frame structure through pre-tightening bolts. The piezoelectric stack generates an output force, which is transmitted to the beam through the adjusting shim, and lateral displacement occurs between the beam and the inclined plane due to uneven distribution of axial stiffness. Increasing the friction driving force in the slow deformation driving stage and reducing the friction resistance in the rapid deformation driving stage can realize the comprehensive regulation of the friction force. The end surface of the driving foot of the inclined trapezoidal stator is correspondingly coated with friction material, the driving foot of the inclined trapezoidal stator drives the mover to move, the pre-tightening screw mounting hole is threaded with the pre-tightening screw, and the piezoelectric stack and the pre-tightening screw are arranged There are adjusting shims.

The mover is a double row cross roller guide rail, including a movable guide rail, a guide rail limit bolt, a fixed guide rail, a double row cross roller guide rail mounting bolt and a double row cross roller guide rail cage. The fixed guide rail is fixed to the fixed installation contact surface of the guide rail through the mounting bolts of the double row cross roller guide rail and the threaded mounting holes of the guide rail. The fixed guide rail is provided with a double row cross roller guide rail cage and rollers to provide support for the sliding of the mover , the two ends of the movable guide rail and the fixed guide rail of the mover are provided with guide rail limit bolts to limit the position.

The composite excitation electrical signal used in the driving method is compositely superimposed on the sawtooth wave in the rapid deformation stage of the stator by the friction regulation wave, the driving wave is a sawtooth wave, and the friction regulation wave is a sine wave. The driving method can reduce the friction resistance between the stator and the mover in the rapid deformation stage, and suppress the generation of retreat motion, wherein the period of the sawtooth wave is T ₁ , the amplitude of the excitation voltage is V ₁ , the symmetry is D, and the friction control wave The period is T ₂ , the amplitude of the excitation voltage is V ₂ , the cycle ratio of the sawtooth wave and the friction control wave is T ₁ /T ₂ =10~100000, and the amplitude ratio of the excitation voltage is V ₁ /V ₂ greater than 2.

The beneficial effects of the present invention are:

Because the present invention adopts the inclined trapezoidal stator structure with the function of comprehensive regulation and control of friction force, and at the same time excites through the composite excitation electric signal, the frictional driving force between the stator and the mover in the stator slow deformation driving stage is increased, and the stator rapid deformation driving stage is reduced. The frictional resistance between the piezoelectric stick-slip linear motor and the mover realizes the comprehensive regulation of the friction force in the entire driving process of the piezoelectric stick-slip linear motor, which can significantly improve the mechanical output characteristics of the piezoelectric stick-slip linear motor and suppress the generation of displacement retreat motion. Compared with the current existing technology, the output force is increased by more than 10%, the output speed is increased by more than 25%, the output efficiency is increased by more than 35%, the displacement retraction rate is reduced by more than 50%, and the positioning accuracy can reach nanometer level under open-loop conditions.

Description of drawings

Fig. 1 shows the structural representation of a kind of oblique trapezoidal motion conversion precision piezoelectric stick-slip linear motor proposed by the present invention;

Fig. 2 is a schematic diagram of the structure of a precision piezoelectric stick-slip linear motor base proposed by the present invention;

Fig. 3 is a schematic structural diagram of an inclined trapezoidal motion conversion precision piezoelectric stick-slip linear motor pre-pressure adjustment device proposed by the present invention;

Fig. 4 is a schematic diagram of the structure of the lower fixed sliding table of a kind of inclined trapezoidal motion conversion type precision piezoelectric stick-slip linear motor pre-pressure adjustment device proposed by the present invention;

Fig. 5 is a schematic structural diagram of the upper movable sliding table of a kind of inclined trapezoidal motion conversion type precision piezoelectric stick-slip linear motor pre-pressure adjustment device proposed by the present invention;

Fig. 6 is a schematic diagram of the structure of an inclined trapezoidal stator of a precision piezoelectric stick-slip linear motor proposed by the present invention;

Fig. 7 is a structural schematic diagram of a frame-shaped flexible hinge of an inclined trapezoidal motion conversion precision piezoelectric stick-slip linear motor proposed by the present invention;

Fig. 8 is a partial enlarged structure schematic diagram of an inclined trapezoidal stator of a kind of inclined trapezoidal motion conversion precision piezoelectric stick-slip linear motor proposed by the present invention;

Fig. 9 is a structural schematic diagram of a precision piezoelectric stick-slip linear motor mover proposed by the present invention;

FIG. 10 is a schematic diagram of electrical signal waveforms of an inclined trapezoidal motion conversion precision piezoelectric stick-slip linear motor driving method proposed by the present invention.

detailed description

Specific implementation manner 1: This implementation manner will be described with reference to FIG. 1 to FIG. 9 . This implementation mode provides a specific implementation scheme of a precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion. The inclined trapezoidal motion conversion precision piezoelectric stick-slip linear motor consists of a base 1 , a pre-pressure adjustment device 2 , an inclined trapezoidal stator 3 and a mover 4 .

The base 1 includes a base installation hole 1-1, a preloading device installation hole 1-2, a guide rail fixed installation contact surface 1-3 and a guide rail threaded installation hole 1-4. The base 1 can be made of high magnetic permeability stainless steel. The base installation hole 1-1 is a base installation threaded hole, which can fix the base 1 and other peripheral devices, and the pre-pressure adjustment device installation hole 1-2 is used for fixing the pre-pressure adjustment device 2. The fixed installation contact surface 1-3 of the guide rail and the threaded installation hole 1-4 of the guide rail are used for fixed installation of the mover 4 .

The pre-pressure adjustment device 2 is a pre-pressure adjustment mechanism of a precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion, and the pre-pressure adjustment device 2 includes a lower fixed sliding table 2-1, an upper movable sliding table 2-2, The pretightening force manually adjusts the screw rod 2-3 and the platform locking screw 2-4. The lower fixed sliding table 2-1 is provided with a threaded hole 2-1-1, which is used for threaded connection with the pretightening force manual adjustment screw 2-3, and the lower fixed sliding table 2-1 is provided with a spring fixed cylinder 2-1-2 is used to install the preloaded spring 2-1-4, and the lower fixed sliding table 2-1 is provided with a guide rail 2-1-3 for moving the upper movable sliding table 2-2. The guide rail 2-1-3 is provided with 8n guide rail limit screws 2-1-5 to prevent the upper movable sliding table 2-2 from exceeding the stroke of the guide rail 2-1-3, wherein n is an integer greater than or equal to 1. The bottom of the lower fixed sliding table 2-1 is provided with a countersunk hole 2-1-6, which can be fixedly installed with the base 1 through screws, and the lower fixed sliding table 2-1 is provided with a locking support frame 2-1-7 and locking support frame fixing screw 2-1-8, by adjusting the platform locking screw 2-4, the locking of the upper movable sliding table 2-2 can be realized to prevent the upper movable sliding table after loading is completed 2-2 moves. The upper end surface of the upper movable sliding table 2-2 is provided with a threaded hole 2-2-1 for fixing and installing the inclined trapezoidal stator 3, and the side of the upper movable sliding table 2-2 is provided with a platform locking screw mounting hole 2 -2-2, the platform locking screw mounting hole 2-2-2 is threadedly connected with the platform locking screw 2-4.

The inclined trapezoidal stator 3 includes a frame-shaped hinge 3-1, a piezoelectric stack 3-2, a pre-tightening bolt 3-3 and an adjusting washer 3-4. The hinge 3-1 of the frame structure adopts a flexible hinge of symmetrical rectangular structure, and the hinge 3-1 of the frame structure adopts 5052 aluminum alloy, 6061 aluminum alloy, 7075 aluminum alloy, Ti-35A titanium alloy or Ti-13 Titanium alloy material. The hinge 3-1 of the frame structure is provided with a fastening bolt mounting hole 3-1-1, and the hinge 3-1 of the frame structure is connected to the threaded hole 2-2-2 on the upper movable sliding table 2-2 through bolts. 1. Perform threaded fastening connection. The right side of the hinge 3-1 of the frame structure is provided with two right straight round flexible hinges 3-1-2, and the left side is provided with two left straight round flexible hinges 3-1. -7. The two right straight round flexible hinges 3-1-2 and the two left straight round flexible hinges 3-1-7 are connected by rigid beams 3-1-3, specifically the two right straight round flexible hinges The hinge 3-1-2 is connected by the rigid beam 3-1-3, the two left straight circular flexible hinges 3-1-7 are connected by the rigid beam 3-1-3, and the right straight circular flexible hinge 3- 1-2 and the left straight circular flexible hinge 3-1-7 are also connected by rigid beams 3-1-3; the distance between the two rigid beams 3-1-3 is L, and the four right The straight round flexible hinge 3-1-2 and the four left straight round flexible hinges 3-1-7 have the same fillet radius value R1, where the value range of R1/L is 0.017~0.09, which can ensure that the two right The straight round flexible hinge 3-1-2 and the two left straight round flexible hinges 3-1-7 have displacement amplification capabilities and the piezoelectric stack 3-2 has a certain installation space. In this embodiment, R ₁ =1mm , L=12mm. The hinge 3-1 of the frame-shaped structure is provided with an inclined plane 3-1-4 with uneven stiffness distribution, the length of the inclined plane 3-1-4 is L ₂ , and the value range of L ₂ /L is 1 ~4. The hinge 3-1 of the frame structure is provided with an inclined trapezoidal stator driving foot 3-1-5, and one end of the piezoelectric stack 3-2 is fixedly installed on the hinge 3-1 of the frame structure through a pre-tightening bolt 3-3. 1, the other end is in contact with the beam 3-1-6, the length of the beam 3-1-6 is L ₁ , where L ₁ /L ranges from 1/6 to 5/6, and the beam 3-1 The included angle between -6 and the inclined plane 3-1-4 is α, where α ranges from 10° to 80°, and the included angle α in this embodiment is 30°. The oblique trapezoidal stator 3 adopts a flexible hinge with a symmetrical rectangular structure for displacement amplification, and the sawtooth wave electric signal excites the piezoelectric stack 3-2 to generate an output force, which is transmitted to the beam 3-1-6 through the adjusting gasket 3-4, The lateral displacement is caused by the uneven distribution of axial stiffness between the beam 3-1-6 and the inclined plane 3-1-4. Increasing the friction driving force in the slow deformation driving stage and reducing the friction resistance in the rapid deformation driving stage can realize the comprehensive regulation of the friction force. The thickness of the inclined trapezoidal stator drive foot 3-1-5 is N, and the thickness of the movable guide rail 4-1 is M, where N≤M can ensure the effective contact area and improve the transmission efficiency, where M=(N+1)mm , M=8mm, N=7mm in this embodiment. The end face of the inclined trapezoidal stator driving foot 3-1-5 is coated with ceramic or glass fiber friction material, the inclined trapezoidal stator driving foot 3-1-5 drives the mover 4 to move, and the pre-tightening screw mounting hole 3 - 1-8 is threadedly connected with the pre-tightening screw 3-3, and the piezoelectric stack 3-2 may be a piezoelectric stack product of a company such as PI or NEC. An adjusting gasket 3-4 is arranged between the rear end surface of the piezoelectric stack 3-2 and the pre-tightening screw 3-3, and the front end surface of the piezoelectric stack 3-2 is connected to the frame-shaped hinge 3-3. 1 is provided with an adjusting gasket 3-4, and the purpose of installing the gasket 3-4 on the front and rear ends of the piezoelectric stack 3-2 is to protect the piezoelectric stack 3-2 and prevent it from generating shear strain or local stress. Uneven force. By adjusting the screw-in length of the pre-tightening screw 3-3, the axial pre-tightening adjustment of the piezoelectric stack 3-2 can be realized.

The mover 4 is a double row cross roller guide rail, including a movable guide rail 4-1, a guide rail limit bolt 4-2, a fixed guide rail 4-3, a double row cross roller guide rail mounting bolt 4-4 and a double row cross roller guide rail. Post rail cage 4-5. The end surface of the movable guide rail 4-1 is coated with ceramic or glass fiber friction material, and the fixed guide rail 4-3 is fixed to the guide rail through the double-row cross roller guide rail mounting bolts 4-4 and the guide rail threaded mounting holes 1-4. The installation contact surface 1-3 is fixed, and the fixed guide rail 4-3 is provided with a double row cross roller guide rail cage 4-5 and rollers, and the double row cross roller guide rail cage 4-5 and rollers are movable The sliding of child 4 provides support. In order to prevent the cage 4-5 and the rollers of the double-row crossed roller guide rail from slipping out of the guide rail, the guide rail limit bolts 4-2 are set at the two ends of the movable guide rail 4-1 and the fixed guide rail 4-3 of the mover 4 to limit the movement. bit.

Specific Embodiment 2: This embodiment will be described with reference to FIG. 10 . This embodiment provides a specific embodiment of a driving method for a precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion. The driving method of a precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion is as follows.

The composite excitation electric signal used in the driving method is compounded and superimposed on the driving wave in the rapid deformation stage of the stator by the friction regulation wave, the driving wave is a sawtooth wave, and the friction regulation wave is a sine wave. Specifically, the driving method can reduce the frictional resistance between the stator and the mover during the rapid deformation stage, suppress the generation of retreat motion, and improve the mechanical output performance. Among them, the cycle of the sawtooth wave is T ₁ , the amplitude of the excitation voltage is V ₁ , the symmetry is D, the cycle of the friction regulation wave is T ₂ , the amplitude of the excitation voltage is V ₂ , and the cycle ratio of the sawtooth wave and the friction regulation wave is T ₁ / T ₂ =10~100000, the excitation voltage amplitude ratio is V ₁ /V ₂ greater than 2.

Working principle: Inclined trapezoidal motion conversion precision piezoelectric stick-slip linear motor and its driving method are mainly under the excitation of composite electric signals, using the inclined trapezoidal drive foot to generate lateral displacement due to uneven distribution of axial stiffness, and comprehensively regulating the stator and The friction force between the movers improves the mechanical output characteristics of the linear piezoelectric motor. Since the stator of the present invention adopts a symmetrical flexible hinge mechanism, the inclined trapezoidal driving foot is used to distribute the axial stiffness unevenly, so as to excite the driving end of the stator to generate lateral displacement, and adjust the positive pressure of the contact between the stator and the moving element, that is, when the stator slowly deforms and drives stage, increase the positive contact pressure between the stator and the mover, and then increase the frictional driving force between the stator and the mover, and reduce the positive pressure between the stator and the mover during the rapid deformation driving stage of the stator, and then reduce the stator and mover The frictional resistance between movers realizes the comprehensive control of the frictional driving force in the slow deformation driving stage and the frictional resistance in the fast deformation driving stage, and improves the output performance of the whole machine. At the same time, the present invention excites the stator to be in a state of slight high-frequency vibration by superimposing the friction control wave on the sawtooth wave in the rapid deformation stage of the stator, thereby improving the transmission contact state between the stator and the mover, and reducing the real friction between the stator and the mover. The contact area and the actual contact time reduce the frictional resistance between the stator and the mover during the rapid deformation driving stage, suppress the back movement, and significantly improve the mechanical output characteristics of the piezoelectric stick-slip linear motor.

Based on the above, the present invention provides a precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion, which uses the uneven distribution of the axial stiffness of the inclined trapezoidal driving foot to generate lateral displacement, and comprehensively controls the distance between the stator and the mover. Friction: The driving method provided by the present invention can suppress the generation of displacement and retreat motion, and significantly improve the mechanical output characteristics of the piezoelectric stick-slip linear motor. The frame-shaped hinge and the piezoelectric stack are assembled into a stator, which is simple to assemble and easy to adjust; the designed pre-pressure adjustment device can easily adjust the pre-tightening force of the contact between the stator and the mover. The invention has the characteristics of simple structure, high precision and large stroke, and has good application prospects in the fields of micro-nano precision driving and positioning such as aerospace, optical precision instruments and semiconductor processing.

Claims (7)

1. A precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion, which consists of a base (1), a pre-pressure adjustment device (2), an inclined trapezoidal stator (3 ) and the mover (4), in which the pre-pressure adjustment device (2) is fixed on the base (1), the inclined trapezoidal stator (3) is installed on the pre-pressure adjustment device (2), and the mover (4) is installed on the on the base (1); it is characterized in that the base (1) includes a base installation hole (1-1), a pre-pressure device installation hole (1-2), a guide rail fixed installation contact surface (1-3) and Guide rail threaded mounting holes (1-4); the base mounting holes (1-1) are base mounting threaded holes, which can fix the base (1) with other peripheral devices, and the pre-pressure adjustment device mounting holes (1 -2), used for fixing the pre-pressure adjustment device (2), the fixed installation contact surface (1-3) of the guide rail and the threaded installation hole (1-4) of the guide rail are used for fixed installation of the mover (4); The pre-pressure adjustment device (2) includes the lower fixed slide (2-1), the upper movable slide (2-2), the pretightening force manual adjustment screw 2-3 and the platform locking screw (2-4); The lower fixed sliding table (2-1) is provided with a threaded hole (2-1-1), which is used for threaded connection with the pre-tightening force manual adjustment screw (2-3), and the lower fixed sliding table (2-1 ) is provided with a spring fixed cylinder (2-1-2) for installing a preloaded spring (2-1-4), and the lower fixed slide table (2-1) is provided with a guide rail (2-1-3), For the movement of the upper movable slide (2-2), the guide rail (2-1-3) is provided with a guide rail limit screw (2-1-5), and the countersunk hole (2-1-6) passes through the screw Realize the connection between the lower fixed slide (2-1) and the base (1), the lower fixed slide (2-1) is provided with a locking support frame (2-1-7) and a locking support frame The fixing screw (2-1-8), the upper movable sliding table (2-2) can be locked by adjusting the platform locking screw (2-4), and the upper end surface of the upper movable sliding table (2-2) is provided with threads Holes (2-2-1) are used to fix and install the inclined trapezoidal stator (3). The side of the upper movable slide (2-2) is provided with platform locking screw mounting holes (2-2-2). Thread the platform locking screw mounting holes (2-2-2) to the platform locking screw (2-4). 2. A precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion according to claim 1, characterized in that the inclined trapezoidal stator (3) includes a frame-shaped hinge (3-1), a piezoelectric Stack (3-2), pre-tightening bolts (3-3) and adjusting gaskets (3-4), the piezoelectric stack (3-2) passes through pre-tightening screws (3-3) and adjusting gaskets (3-4) is fixed in the hinge (3-1) of the frame structure; the hinge (3-1) of the frame structure is provided with a fastening bolt installation hole (3-1-1), and the frame is fixed by the bolt The hinge (3-1) of the frame structure is threaded and fastened to the threaded hole (2-2-1) on the upper movable slide (2-2), and the right side of the hinge (3-1) of the frame structure There are 2 right straight round flexible hinges (3-1-2), the left side is provided with 2 left straight round flexible hinges (3-1-7), and the 2 right straight round flexible hinges ( 3-1-2) and two left straight round flexible hinges (3-1-7) are connected by rigid beams (3-1-3), specifically two right straight round flexible hinges (3-1- 2) Connected by a rigid beam (3-1-3), the two left straight round flexible hinges (3-1-7) are connected by a rigid beam (3-1-3), and the right straight round flexible hinge (3-1-2) and the left straight circular flexible hinge (3-1-7) are also connected by a rigid beam (3-1-3); the hinge (3-1) of the frame structure is provided with a beam (3-1-6) and inclined plane (3-1-4), the piezoelectric stack (3-2) transmits the output force to the beam (3-1-6 ), the beam (3-1-6) and the inclined plane (3-1-4) are integrally structured, and the hinge (3-1) of the frame structure is provided with an inclined trapezoidal stator driving foot (3- 1-5), the driving foot (3-1-5) of the inclined trapezoidal stator is located at the upper end of the hinge (3-1) of the frame structure, and is respectively connected to the right straight circular flexible hinge (3-1-2) and the left The straight round flexible hinge (3-1-7) is rigidly connected, the end face of the inclined trapezoidal stator driving foot (3-1-5) is coated with friction material, and the inclined trapezoidal stator driving foot (3-1-5) drives the mover ( 4) Movement, the hinge (3-1) of the frame-shaped structure is provided with a pre-tightening screw installation hole (3-1-8), and the pre-tightening screw installation hole (3-1-8) is located in the hinge of the frame-shaped structure ( At the center of the lower end of 3-1), the pre-tightening screw mounting hole (3-1-8) is threaded with the pre-tightening screw (3-3), and the rear end surface of the piezoelectric stack (3-2) is connected to the An adjusting gasket (3-4) is arranged between the pre-tightening screws (3-3), and a By adjusting the washer (3-4), the axial preload adjustment of the piezoelectric stack (3-2) can be realized by adjusting the screw-in length of the preload screw (3-3). 3. An oblique trapezoidal motion conversion precision piezoelectric stick-slip linear motor according to claim 2, characterized in that the two right straight circular flexible hinges (3-1-2) and the two left straight circular Type flexible hinges (3-1-7) have the same fillet radius value R ₁ , the distance between the rigid beams (3-1-3) is L, and the inclined plane (3-1-4) The length is L ₂ , where L ₂ /L ranges from 1 to 4, and the beam (3-1-6) has a length of L ₁ , where L ₁ /L ranges from 1/6 to 5/6, The angle between the beam (3-1-6) and the inclined plane (3-1-4) is α, where α ranges from 10° to 80°. 4. A precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion according to claim 2, characterized in that the hinge (3-1) of the frame structure is made of 5052 aluminum alloy, 6061 aluminum alloy, 7075 aluminum alloy alloy, Ti-35A titanium alloy or Ti-13 titanium alloy material. 5. A precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion according to claim 2, characterized in that the end surface of the inclined trapezoidal stator driving foot (3-1-5) of the inclined trapezoidal stator (3) is correspondingly coated with Ceramic or glass fiber friction materials. 6. A precision piezoelectric stick-slip linear motor with inclined trapezoidal motion conversion according to claim 1, characterized in that the mover (4) is a double-row crossed roller guide rail, including movable guide rails (4 -1), guide rail limit bolt (4-2), fixed guide rail (4-3), double row cross roller guide rail mounting bolt (4-4) and double row cross roller guide rail cage (4-5); The end surface of the movable guide rail (4-1) is coated with ceramic or glass fiber friction material, and the fixed guide rail (4-3) is fixed through the double-row cross roller guide rail mounting bolts (4-4) and guide rail threaded mounting holes. (1-4) is fixed with the fixed installation contact surface (1-3) of the guide rail, and the fixed guide rail (4-3) is provided with a double-row cross roller guide rail cage (4-5) and rollers, movers (4 ) The two ends of the movable guide rail (4-1) and the fixed guide rail (4-3) are provided with guide rail limit bolts (4-2). 7. A drive method for a precision piezoelectric stick-slip linear motor with an oblique trapezoidal motion conversion, the driving method is realized based on the oblique trapezoidal motion conversion type precision piezoelectric stick-slip linear motor according to claim 1; the driving method is characterized in that it drives The wave is a sawtooth wave, and the friction control wave is a sine wave. The period of the sawtooth wave is T ₁ , the amplitude of the excitation voltage is V ₁ , the symmetry is D, the period of the friction control wave is T ₂ , and the amplitude of the excitation voltage is V ₂ . The cycle ratio of wave and friction control wave is T ₁ /T ₂ =10~100000, and the amplitude ratio of excitation voltage is V ₁ /V ₂ greater than 2.