CN110855181A - A Rotary Piezoelectric Drive Device Based on Asymmetric Triangular Hinged Mechanism - Google Patents

Abstract

The invention relates to a rotary piezoelectric driving device based on an asymmetric triangular hinge mechanism, which is composed of a piezoelectric stack, an asymmetric triangular hinge mechanism, a rotor, a pre-tightening screw, a pre-tightening wedge and a base. The piezoelectric stack can be stretched and restored under the drive of voltage signal; the asymmetric triangular hinge mechanism can realize parasitic inertial motion; the preload screw and the preload wedge adjust the initial preload force between the asymmetric triangular hinge mechanism and the rotor; the base play a supporting role. The main output direction of the piezoelectric stack and the rotation center of the rotor are in a straight line, and the rigidity of the main output direction of the piezoelectric stack can be fully utilized; the asymmetric triangular hinge mechanism has a simple structure, good stiffness output performance, and can withstand large The output load of the drive device is greatly improved, and the rotary step-type movement of the rotor can be realized. The device can be applied to the fields of precision ultra-precision machining, micro-electromechanical systems, micro-manipulation robots, large-scale integrated circuit manufacturing, and biotechnology.

Description

A Rotary Piezoelectric Drive Device Based on Asymmetric Triangular Hinged Mechanism

technical field

The invention relates to the fields of precision ultra-precision machining, micro-nano operation robots, and micro-electromechanical systems, in particular to a rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism.

Background technique

Precision drive technology with micro/nano-level positioning accuracy is a key technology in high-tech fields such as ultra-precision machining and measurement, optical engineering, modern medical care, and aerospace technology. In order to achieve micro/nano-level output precision, the application of modern precision drive technology puts forward higher requirements for the precision of the drive device. The traditional driving device has low output precision and large overall size, which cannot meet the requirements of micro/nano-level high precision and small size of the driving device in the precision system of modern advanced technology. Piezoelectric ceramic drivers have the advantages of small size, high displacement resolution, large output load, and high energy conversion rate. They can achieve micro/nano-level output accuracy, and have been increasingly used in micro-positioning and precision ultra-precision machining. middle. The existing piezoelectric inertial drive device usually places the piezoelectric element and the rotor mass in parallel to its motion direction, the preload force is perpendicular to the main output direction of the piezoelectric element, and the output load of the overall device mainly depends on the preload force. friction. However, piezoelectric elements such as piezoelectric stacks usually use the d33 working mode, which has less rigidity on the cross-section perpendicular to the main output direction, and generates less preload, which greatly reduces the output load of the overall device, and the piezoelectric The greater stiffness of the element in the main output direction is not fully utilized. Therefore, it is necessary to design a new type that makes full use of the stiffness in the main output direction of the piezoelectric stack and generates preload and driving force through the parasitic inertial motion of the asymmetric triangular hinge mechanism to further improve the output load of the piezoelectric drive. Piezoelectric rotary precision drive.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism, which solves the above problems existing in the prior art. The invention has the characteristics of simple and compact structure, high output precision, large output rigidity and output load, and high output frequency, and at the same time, it can realize the output function of rotary motion.

The invention arranges the main output direction of the piezoelectric stack and the rotation center of the rotor on a straight line, adopts an asymmetric triangular hinge mechanism with good rigidity output characteristics, and transmits the compound load through the asymmetric triangular hinge mechanism, and finally realizes the rotation of the rotor. .

The above-mentioned purpose of the present invention is achieved through the following technical solutions:

A rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism, mainly comprising a rotor (1), a piezoelectric stack (2), a pre-tightening wedge (3), a pre-tightening screw (4), and an asymmetric triangular hinge A mechanism (5) and a base (6) are provided, and the precision driving device realizes the precise driving of piezoelectric rotation through the principle of parasitic inertia. The structure of the rotor (1) uses a high-precision bearing to reduce its friction loss. The bearing is connected to the base through a rotating shaft; the rotor (1) includes a rotating table, a bearing and a rotating shaft, the rotating table and the outer ring of the bearing, and the rotating shaft and the bearing. The inner ring, the rotating shaft and the base are in interference fit; the asymmetric triangular hinge mechanism (5) is installed on the base by screws; the piezoelectric stack (2) is installed in the asymmetric triangular hinge mechanism (5), and its main output direction is On a straight line with the rotation center of the rotor (1); the preload wedge (3) is arranged between the piezoelectric stack (2) and the asymmetric triangular hinge mechanism (5), which can be adjusted by the preload wedge (3). Pre-tightening; the pre-tightening screw (4) is fastened on the base and is in contact with the lower end of the asymmetrical thin-walled hinge. The asymmetrical triangular hinge mechanism (5) is an asymmetrical thin-walled structure, and the arc-shaped structure at its upper end is in contact with the rotor (1). ) contact; the base (6) plays the role of supporting and installing and fixing other parts.

The main output direction of the piezoelectric stack (2) is on a straight line with the rotation center of the rotor (1), so that the greater rigidity of the piezoelectric stack (2) in the main output direction is fully utilized; the asymmetric triangle The hinge mechanism (5) has good rigidity output performance, the upper end of the asymmetric triangular hinge mechanism can bear a large pre-tightening force, and the movement is stable and efficient, and the piezoelectric stack (2) is powered through the asymmetric triangular hinge mechanism (5) to transmit the rotor ( 1) The driving force of the rotary motion and the preload of the contact surface between the asymmetric triangular hinge mechanism (5) and the rotor (1), thereby greatly increasing the output load of the piezoelectric drive. Rotational step-by-step motion in the desired direction is possible.

The initial pre-tightening force between the asymmetric triangular hinge mechanism (5) and the rotor (1) is adjusted by the pre-tightening screw (4);

The piezoelectric stack (2) adopts the piezoelectric ceramic stack PZT of the shape controllable surface type, and the parasitic inertial motion drive is realized by voltage control of the piezoelectric stack (2).

The main advantage of the present invention lies in: using the principle of parasitic inertial motion, the main output direction of the piezoelectric stack and the rotor rotation center are aligned on a straight line, and the parasitic inertial motion of the asymmetric triangular hinge mechanism is used to transmit the load, which greatly improves the driving device. The load is output, and the rotary motion of the rotor is realized at the same time. It has the advantages of high driving reliability, good stability and high working efficiency. It can be applied to important scientific and engineering fields such as precision ultra-precision machining, micro-manipulation robots, micro-electromechanical systems, large-scale integrated circuit manufacturing, and biotechnology. The invention has the advantages of simple structure, compact arrangement, stable movement, high efficiency, low investment, high benefit, and broad application prospect.

Description of drawings

The accompanying drawings here are used to provide a further understanding of the present invention and constitute a part of the present application. The schematic examples of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

1 is a schematic isometric view of the present invention;

2 is a schematic front view of the present invention;

Fig. 3 is the left side view schematic diagram of the present invention;

4 is a schematic diagram of the asymmetric triangular hinge mechanism of the present invention.

In the picture:

1. Rotor; 2. Piezoelectric stack; 3. Preload wedge;

4. Pre-tightening screws; 5. Asymmetric triangular hinge mechanism; 6. Base.

Detailed ways

The details of the present invention and the specific implementations thereof will be further described below with reference to the accompanying drawings.

1 to 4, a rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism mainly includes a rotor (1), a piezoelectric stack (2), a preload wedge (3), a preload The screw (4), the asymmetric triangular hinge mechanism (5) and the base (6), the driving device realizes the precise driving of piezoelectric rotation through the principle of parasitic inertia. The rotor (1) includes a rotary table, a bearing and a rotary shaft. The rotary table and the outer ring of the bearing, the rotary shaft and the inner ring of the bearing, and the rotary shaft and the base are in interference fit; the structure of the rotor (1) uses high-precision bearings to reduce Its friction loss, the bearing is connected with the base through the rotating shaft; the asymmetric triangular hinge mechanism (5) is installed on the base through screws; the piezoelectric stack (2) is installed in the asymmetric triangular hinge mechanism (5), and its main output direction On a straight line with the rotation center of the rotor (1); the preload wedge (3) is arranged between the piezoelectric stack (2) and the asymmetric triangular hinge mechanism (5), which can be adjusted by the preload wedge (3). Pre-tightening; the pre-tightening screw (4) is fastened on the base and is in contact with the lower end of the asymmetrical thin-walled hinge. ) contact; the base (6) plays the role of supporting and installing and fixing other parts.

The main output direction of the piezoelectric stack (2) is on a straight line with the rotation center of the rotor (1), so that the greater rigidity of the piezoelectric stack (2) in the main output direction is fully utilized; the asymmetric triangle The hinge mechanism (5) has good rigidity output performance, the upper end of the asymmetric triangular hinge mechanism (5) can bear a large pre-tightening force, the movement is stable and efficient, and the piezoelectric stack (2) is energized through the asymmetric triangular hinge mechanism (5) It transmits the driving force of the rotary motion of the rotor (1) and the pre-tightening force between the asymmetric triangular hinge mechanism (5) and the rotor (1), thereby greatly increasing the output load of the piezoelectric drive device and realizing rotation in a certain direction Step movement.

The initial pre-tightening force between the asymmetric triangular hinge mechanism (5) and the rotor (1) is adjusted by the pre-tightening screw (4);

The piezoelectric stack (2) adopts the piezoelectric ceramic stack PZT of the shape controllable surface type, and the parasitic inertial motion is realized by voltage control of the piezoelectric stack (2).

1 to 4, the specific working process of the present invention is as follows:

The realization of the step-by-step rotary motion of the rotor, the initial state: adjust the pre-tightening screw (4) to adjust the contact distance between the asymmetric triangular hinge mechanism (5) and the rotor (1), that is, the initial pre-tightening force during the parasitic motion. The piezoelectric stack (2) is controlled using a piezoelectric signal in the form of a sawtooth or triangular wave. The piezoelectric stack (2) is not charged, and the system is in a free state; when the piezoelectric stack (2) is energized, it stretches through the inverse piezoelectric effect, pushing the asymmetric triangular hinge mechanism (5) to deform, and the asymmetric triangular hinge mechanism (5) Press the rotor (1), and the asymmetric triangular hinge mechanism (5) drives the rotor (1) to rotate under the action of the static friction force with the rotor (1); when the piezoelectric stack (2) loses power, it returns quickly. When returning to the initial position, the asymmetric triangular hinge mechanism (5) also returns to the initial state, and the rotor (1) remains in the rotated position under the action of inertial force, thus completing one movement cycle of the driving device. By repeating the above steps, the driving device can realize rotational motion and obtain a larger output rotational angle.

The invention relates to a rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism, which adopts a piezoelectric stack as a driving source and an asymmetric triangular hinge mechanism as a power transmission element, and has the advantages of low heat generation, stable driving, reliability and high efficiency. It can realize functions such as step-by-step rotary precision motion.

Claims (5)

1. A rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism, comprising a rotor (1), a piezoelectric stack (2), a preload wedge (3), a preload screw (4), an asymmetric triangle The hinge mechanism (5) and the base (6) are characterized in that: the precision driving device utilizes the principle of parasitic inertia to realize the step-type large-stroke rotational motion of the rotor (1). The rotor (1) includes a rotary table, a bearing and a rotary shaft. The rotary table and the outer ring of the bearing, the rotary shaft and the inner ring of the bearing, and the rotary shaft and the base are in interference fit; the structure of the rotor (1) uses high-precision bearings to reduce Its friction loss, the bearing is connected with the base through the rotating shaft to realize high-precision rotary motion; the asymmetric triangular hinge mechanism (5) is installed on the base by screws; the piezoelectric stack (2) is installed on the asymmetric triangular hinge mechanism In (5), the pre-tightening can be performed by the pre-tightening wedge (3); the pre-tightening screw (4) can adjust the initial pre-tightening force between the asymmetric triangular hinge mechanism (5) and the rotor (1); The precision driving device realizes the parasitic inertial motion by controlling the piezoelectric stack (2) to drive the asymmetric triangular hinge mechanism (5), and then drives the rotor (1) to realize the stepping rotary precision motion. 2. The rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism according to claim 1, wherein the designed asymmetric triangular hinge mechanism (5) can be made of materials such as spring steel, high-strength aluminum alloys, etc. Two thin-walled flexible hinges are connected to form an asymmetrical triangular structure with good stiffness output characteristics. During parasitic inertial motion, the contact surface between the asymmetrical triangular hinge mechanism (5) and the rotor (1) can bear a large preload force , which is beneficial to improve the output load of the piezoelectric drive. 3. The rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism according to claim 1, wherein the main output direction of the piezoelectric stack (2) is on a straight line with the rotation center of the rotor (1), And the stress direction of the asymmetric triangular hinge mechanism (5) is consistent with the main output direction of the piezoelectric stack (2), and the greater stiffness of the piezoelectric stack (2) in the main output direction is fully utilized, and the asymmetric triangular hinge The parasitic inertial motion of the mechanism (5) is greatly increased, thereby greatly increasing the output load of the piezoelectric drive. 4. The rotary piezoelectric drive device based on an asymmetric triangular hinge mechanism according to claim 1 is characterized in that adopting the parasitic inertia driving principle of the asymmetric triangular hinge mechanism (5), a single piezoelectric stack (2) obtains The asymmetric triangular hinge mechanism (5) is electrically driven to generate compound forces in two directions. The force in one direction is used as a driving force to push the rotor (1) to rotate, and the force in the other direction applies a pre-tightening force to the upper-tightening rotor (1). , the advantage is that the asymmetric triangular hinge mechanism is simple in structure, provides driving force and preloading force at the same time, and improves the output load performance. 5. The rotary piezoelectric driving device based on an asymmetric triangular hinge mechanism according to claim 1, characterized in that a piezoelectric signal in the form of a sawtooth wave or a triangular wave is used to control the piezoelectric stack (2), so that the piezoelectric stack is (2) Elongate slowly, and push the asymmetric triangular hinge mechanism to perform compound motion, so as to realize the rotational motion of the rotor (1); the piezoelectric stack (2) quickly retreats under the control of the piezoelectric signal, and the rotor (1) is under the action of inertia. Keep the rotated angle unchanged.

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