CN103963033B - The one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle - Google Patents

Abstract

The invention relates to a precise one-dimensional motion occasion and can be used for precise displacement compensation of a general one-dimensional motion platform. The invention specifically relates to a one-dimensional micro-motion platform with adjustable stiffness and frequency based on the principle of stress stiffening, including a motion sub-platform, a corresponding driver, and a micro-motion working platform, and uses a film group that adjusts tension through a frequency adjustment mechanism as a flexible hinge to realize Manual or dynamic adjustment of vibration frequency of one-dimensional micro-motion platform. The present invention adopts the above-mentioned structure, is based on the prestressed film, and has adjustable frequency, and can adjust the natural frequency of the micro-motion platform before or during work according to different working conditions and driving frequencies.

Description

Stiffness Frequency Adjustable One-dimensional Micro-motion Platform Based on Stress Stiffening Principle

technical field

The invention relates to a precision motion platform, which can be used for precision operation and macro-micro composite high-speed precision compensation. The invention specifically relates to a one-dimensional micro-motion platform with adjustable stiffness and frequency based on the principle of stress rigidification.

Background technique

In order to realize one-dimensional precision movement, accurate and stable feed mechanism is particularly important, because it is closely related to the quality of the product. In addition, due to the small size and high precision of the complex optical free-form surface, strict requirements are placed on the micro-feed mechanism. The micro-feed system is the basis for processing such products, and it is widely used in fast-tool servo feed systems, micro-motion worktables, and macro-micro composite platforms. The traditional one-dimensional micro-feeding device usually adopts a fixed frequency design, which puts forward extremely high requirements on material characteristics and manufacturing errors. Especially when processing different products, its driving frequency usually changes, so that the displacement amplification factor of the fixed frequency motion platform Inconsistent, which makes the displacement amplification distortion.

Prior Technology 1: Fast Knife Servo with Adjustable Stiffness (Patent Application No. 201210055119.X) invented a fast knife servo mechanism with adjustable stiffness. The principle of this mechanism is to use symmetrically arranged flexible hinges to eliminate vertical accompanying motion . The stiffness adjustment is through the compression spring installed in the front, the stiffness can only be changed by replacing the spring, and cannot be continuously adjusted.

Prior art 2: A frequency-adjustable fast-knife servo feed device based on a flexible hinge amplifying mechanism (invention application number: 201210250524.7) invented a fast-knife servo mechanism based on a flexible hinge film. The principle of frequency adjustment is through the tension of the film. Continuously adjustable frequency and stiffness can be realized. However, the mechanism adopts a displacement amplification method and there is a flexible hinge with stress concentration, which affects the service life of the mechanism.

In addition, when the above two inventions are driven by piezoelectric ceramics, the load is transmitted through contact, and a certain pre-tightening force is required, resulting in a movement gap during the contact process and asymmetric work of the flexible hinge. For this reason, the present invention cancels the flexible hinge amplifying mechanism, and uses a voice coil motor to replace the piezoelectric ceramics. Through non-contact driving and displacement measurement, the load condition can be judged in real time, and the driving mechanism can be dynamically adjusted according to the change of the load condition. Frequency, intelligent matching of dynamic characteristics can be realized.

Contents of the invention

The purpose of the present invention is to propose a one-dimensional micro-motion platform with adjustable stiffness and frequency based on the principle of stress stiffening. Based on the prestressed film, the frequency can be adjusted to meet the requirements of different motion characteristics.

For reaching this purpose, the present invention adopts following technical scheme:

A one-dimensional micro-motion platform with adjustable stiffness and frequency based on the principle of stress stiffening, characterized in that it includes a frame (1), a film group (201), a motion sub-platform (202), an outer frame (203), a driver, and a working platform (4) and frequency adjustment mechanism (7);

Both sides of the moving sub-platform (202) are connected with the inner wall of the outer frame (203) through the film group (201), the films in the film group (201) are arranged in parallel, and the length of the film is The direction is perpendicular to the moving direction of the moving sub-platform (202);

The outer frame (203) is rigidly fixed to the frame (1), and the working platform (4) is rigidly fixed to the moving sub-platform (202);

The driver includes a stator (301) and a mover (302), the stator (301) is fixed on the frame (1) or the outer frame (203), and the mover (302) is fixed on on the sports sub-platform (202);

A groove (2) is provided at the joint between the outer frame (203) and the film group (201), so that a thinner deformable elastic member (5) is formed inside the outer frame (203), and the outer frame (203) The frequency adjustment mechanism (7) for adjusting the degree of deformation of the elastic member (5) is provided.

It also includes a micro-displacement sensor (6), which is arranged at the end of the moving sub-platform (202) in the feeding direction.

The micro-displacement sensor (6) is a capacitive sensor.

The micro-displacement sensor (6) is an inductive sensor.

The non-working surface of the micro-displacement sensor (6) is provided with an insulating layer.

The film group (201), the moving sub-platform (202) and the outer frame (203) are of an integrated structure.

The driver is a voice coil motor.

The driver is a piezoelectric ceramic driver.

The frequency adjusting mechanism (7) is a bolt passing through the slot (2), and its two ends are respectively connected to both sides of the slot (2).

The frequency adjustment mechanism (7) is a piezoelectric ceramic driver passing through the slot (2), and its two ends are respectively connected to both sides of the slot (2).

The technical principle of the frequency adjustment of the micro-motion platform proposed by the present invention is: the natural frequency of the compliant mechanism composed of the prestressed film is related to the tension of the prestressed film, and the natural frequency of the mechanism is adjusted by adjusting the tension in the prestressed film , to meet the requirements of different working conditions.

Due to the adoption of the above technical solution, the frequency-adjusted one-dimensional micro-motion platform proposed by the present invention has the following advantages:

1. A design scheme based on adjusting the tension of the prestressed membrane to change the natural frequency of the mechanism is adopted, which can manually or dynamically adjust the motion characteristics of the mechanism, and improve the performance of the micro-motion platform.

2. The large-mass stators of the driver in the one-dimensional micro-motion platform proposed by the present invention are all fixed on the frame, which reduces the motion inertia of the micro-motion platform and is conducive to improving the response speed of the micro-motion platform.

3. The one-dimensional micro-movement platform proposed by the present invention adopts an integrated compliant mechanism to realize one-dimensional displacement, without gaps between motion pairs, and can adapt to the working environment with high execution frequency.

Description of drawings

Fig. 1 is a structural axonometric schematic view of an example of the present invention

Fig. 2 is the front view of a kind of example of the present invention

Fig. 3 is a schematic view of the integrated structure of the film group, the motion sub-platform and the outer frame of the one-dimensional micro-motion platform of the present invention

Fig. 4 is the structural axonometric schematic diagram of another kind of example of the present invention

Fig. 5 is a front view of another example of the present invention.

Among them, frame 1, slot 2, film group 201, motion sub-platform 202, outer frame 203, stator 301, mover 302, working platform 4, elastic member 5, micro-displacement sensor 6, frequency adjustment mechanism 7, piezoelectric ceramics Sheet 701, outer frame 203.

detailed description

The technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and through specific implementation methods.

As shown in Figures 1 and 2, the one-dimensional micro-motion platform with adjustable stiffness and frequency based on the principle of stress stiffening includes a frame 1, a film group 201, a motion sub-platform 202, an outer frame 203, a driver, a working platform 4 and a frequency Adjustment mechanism 7;

Both sides of the moving sub-platform 202 are connected to the inner wall of the outer frame 203 through the film group 201, the films in the film group 201 are arranged in parallel, and the length direction of the films is perpendicular to the moving sub-platform 202 movement direction;

The outer frame 203 is rigidly fixed to the frame 1, and the working platform 4 is rigidly fixed to the moving sub-platform 202;

The driver includes a stator 301 and a mover 302, the stator 301 is fixed on the frame 1 or the outer frame 203, and the mover 302 is fixed on the moving sub-platform 202 for driving movement sub-platform 202;

The connection between the outer frame 203 and the film group 201 is provided with a groove 2, so that the inner side of the outer frame 203 forms a thinner deformable elastic member 5, and the outer frame 203 is provided to adjust the deformation of the elastic member 5 Degree of the frequency adjustment mechanism 7.

The driver drives the moving sub-platform 202 and the working platform 4 connected thereto to generate one-dimensional micro-displacement feeding. Under the restraining effect of the film group 201, the movement of the moving part in the non-feeding direction is restrained.

The working platform is equipped with functional components such as knives, which generate one-dimensional displacement under the driving action of the driver to complete the corresponding process action.

Changing the degree of tightness of the membrane group 201 through the frequency adjustment mechanism 7 can change the natural frequency of the mechanism in the above-mentioned micro-motion, thereby changing the motion characteristics of the working platform 4 .

It also includes a micro-displacement sensor 6 arranged at the end of the moving sub-platform 202 in the feeding direction. It is used for detecting the one-dimensional micro-displacement of the working platform 4 .

The micro-displacement sensor 6 is a capacitive sensor.

The micro displacement sensor 6 is an inductive sensor.

The non-working surface of the micro-displacement sensor 6 is provided with an insulating layer, which is used to prevent the displacement sensor from being interfered by other metal materials and affecting the measurement accuracy.

As shown in FIG. 3 , the membrane group 201 , the moving sub-platform 202 and the outer frame 203 are in an integrated structure. The entire material is obtained by milling, EDM, etc., which avoids the assembly error of the parts and improves the movement accuracy of the platform.

The driver is a voice coil motor.

The driver is a piezoelectric ceramic driver.

The frequency adjusting mechanism 7 is a bolt passing through the slot 2 , and its two ends are respectively connected to both sides of the slot 2 .

The frequency adjustment mechanism 7 is a bolt. The bolts can be manually adjusted to generate displacement in the length direction, changing the degree of deformation of the elastic member 5, and further changing the film tension of the film group 201, so as to realize the dynamic adjustment of the structural natural frequency of the platform.

The frequency adjustment mechanism 7 is a piezoelectric ceramic driver passing through the slot 2 , and its two ends are respectively connected to both sides of the slot 2 .

As shown in FIG. 4 and FIG. 5 , the frequency adjustment mechanism 7 includes bolts and piezoelectric ceramic sheets 701 . The piezoelectric ceramic sheet 701 can generate displacement in the length direction of the bolt under the action of the applied voltage, changing the degree of deformation of the elastic member 5, and then changing the film tension of the film group 201, so as to realize the inherent structural stability of the platform. Dynamic adjustment of frequency.

The above describes the technical principles of the present invention in conjunction with specific embodiments. These descriptions are only for explaining the principles of the present invention, and cannot be construed as limiting the protection scope of the present invention in any way. Based on the explanations herein, those skilled in the art can think of other specific implementation modes of the present invention without creative efforts, and these modes will all fall within the protection scope of the present invention.

Claims (10)

1. based on the one-dimensional micromotion platform of rigidity frequency-adjustable of Stress stiffening principle, it is characterised in that: include frame (1), thin film group (201), motion sub-platform (202), outside framework (203), driver, work platforms (4) and frequency adjustment mechanism (7)；

The both sides of described motion sub-platform (202) are connected with described outside framework (203) inwall by described thin film group (201), thin film in described thin film group (201) is for being arranged in parallel, and the length direction of described thin film is perpendicular to the direction of motion of described motion sub-platform (202)；

Described outside framework (203) is rigidly secured to described frame (1), and described work platforms (4) is rigidly secured to described motion sub-platform (202)；

Described driver includes stator (301) and mover (302), described stator (301) is fixed on described frame (1) or described outside framework (203), and described mover (302) is fixed on described motion sub-platform (202)；

Described outside framework (203) and described thin film group (201) junction are provided with groove (2), making described outside framework (203) inner side form relatively thin deformable elastic component (5), described outside framework (203) is provided with the described frequency adjustment mechanism (7) regulating described elastic component (5) degree of deformation.

2. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 1, it is characterised in that: also include micro-displacement sensor (6), be located at the end of the direction of feed of described motion sub-platform (202).

3. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 2, it is characterised in that: described micro-displacement sensor (6) is capacitance type sensor.

4. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 2, it is characterised in that: described micro-displacement sensor (6) is inductance type transducer.

5. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 2, it is characterised in that: the non-working surface of described micro-displacement sensor (6) is provided with insulating barrier.

6. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 1, it is characterised in that: described thin film group (201), motion sub-platform (202) and outside framework (203) they are integral type structure.

7. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 1, it is characterised in that: described driver is voice coil motor.

8. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 1, it is characterised in that: described driver is piezoelectric ceramic actuator.

9. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 1, it is characterized in that: described frequency adjustment mechanism (7) is the bolt through described groove (2), and its two ends are connected to the both sides of described groove (2).

10. the one-dimensional micromotion platform of rigidity frequency-adjustable based on Stress stiffening principle according to claim 1, it is characterized in that: described frequency adjustment mechanism (7) is the piezoelectric ceramic actuator through described groove (2), and its two ends are connected to the both sides of described groove (2).