CN208226897U - A kind of differential rotary piezoelectric stepper motor - Google Patents

Abstract

The utility model discloses a kind of differential rotary piezoelectric stepper motors, including driving assembly, mover, pre-tightening mechanism and pedestal, the pre-tightening mechanism includes the shaft affixed with the pedestal, the mover is fixedly connected with the shaft, the driving component one end connects the pedestal, and the other end hugs the mover by the pre-tightening mechanism.The driving component includes the first driving foot, the second driving foot and third driving foot being distributed in a ring around shaft, the first driving foot, the second driving foot and third driving foot all have displacement converted mechanism, the displacement converted mechanism is equipped with stacked piezoelectric ceramics, and makes the mover rotation to drive the shaft to rotate by displacement converted mechanism described in the stacked piezoelectric ceramic driving.The differential rotary piezoelectric stepper motor of the utility model is used to solve the problems, such as that existing stepper motor presence to cut off self-lock, high thrust is difficult to take into account with high-precision.

Description

A Differential Rotary Piezoelectric Stepper Motor

technical field

The utility model relates to the technical field of piezoelectric precision braking, in particular to a differential rotary piezoelectric stepping motor.

Background technique

At present, there are mainly two ways to realize precision stepping motor drive: inchworm precision drive and inertial friction drive. The inchworm type precision drive can provide greater precision and thrust, but due to its complex structure, the driving frequency is small, resulting in low driving speed, and the complex structure also makes the control more difficult, and the installation accuracy is difficult to control. In addition, the inchworm type The matching wear of the precision drive is serious, which eventually leads to poor contact and weakened performance; the structure of the friction inertial piezoelectric drive device is relatively simple, the control is easier, and the driving speed is relatively large, but due to the lack of clamping mechanism of the friction inertial piezoelectric drive Insufficient tightening force and small thrust.

Due to the superior performance of laminated piezoelectric ceramics, the improvement of manufacturing technology and the realization of mass production in recent years have been more and more used in precision drives. The laminated piezoelectric ceramic has stable output displacement with nanometer precision, and has the characteristics of good linearity, convenient control, high resolution, high response frequency, less heat generation, no magnetic interference, and low noise. Therefore, the piezoelectric Drives have unique advantages. In recent years, piezoelectric precision drive technology has become one of the research hotspots in the field of precision drive at home and abroad. However, the main problem of the current non-resonant piezoelectric motor is the hysteresis effect of laminated piezoelectric ceramics, which leads to the accumulation of the return error of the piezoelectric motor and increases its positioning error. The bipedal drive piezoelectric linear motor that can solve this problem is also There is a problem that it is difficult to balance high thrust and high precision.

Utility model content

The purpose of this utility model is to overcome the deficiencies of the prior art, to provide a differential rotary piezoelectric stepper motor, which comprehensively utilizes the advantages of piezoelectric precision drive and frictional inertia piezoelectric drive, and solves the problems of power-off self-locking, large thrust and high Difficult to take into account the problem of precision.

The technical scheme that the utility model solves its technical problem adopts is:

A differential rotary piezoelectric stepper motor, comprising a drive assembly, a mover, a pre-tension mechanism and a base, the pre-tension mechanism includes a rotating shaft affixed to the base, and the mover is fixedly connected to the rotating shaft , one end of the drive assembly is connected to the base, and the other end hugs the mover tightly through the pre-tensioning mechanism;

The driving assembly includes a first driving foot, a second driving foot and a third driving foot which are annularly distributed around the rotating shaft, and each of the first driving foot, the second driving foot and the third driving foot has a displacement conversion mechanism, and the displacement The conversion mechanism is provided with laminated piezoelectric ceramics, and the displacement conversion mechanism is driven by the laminated piezoelectric ceramics to rotate the mover to drive the rotating shaft to rotate.

In a preferred embodiment, the first driving foot, the second driving foot and the third driving foot also include wear-resistant ceramic balls, and the wear-resistant ceramic balls are arranged between the displacement conversion mechanism and the mover and vertically Push against the displacement conversion mechanism and mover.

In a preferred embodiment, the pre-tightening mechanism further includes a spring, a metal ring and a hex nut arranged at one end of the rotating shaft, the spring is sleeved on the rotating shaft, and the metal ring is connected to the spring.

In a preferred embodiment, the first driving foot, the second driving foot and the third driving foot are arranged at equal intervals around the rotating shaft.

In a preferred embodiment, the mover is a wear-resistant metal disc.

In a preferred embodiment, the wear-resistant ceramic balls of the first driving foot, the second driving foot and the third driving foot are spheres with the same shape and size.

Compared with the prior art, the utility model has the following beneficial effects:

(1) The piezoelectric stepping motor of the present utility model adopts the design of three driving feet, and the three driving feet are arranged at equal intervals relative to the mover. The displacement conversion mechanism is transmitted to the mover to make the mover rotate; when the three-phase voltage control signal is input to the three driving feet, differential motion can be realized, thereby achieving both high thrust and high precision.

(2) The three driving feet of the piezoelectric stepping motor described in the utility model are always pressed on the mover by the pre-tightening mechanism, which makes the motor have the ability of self-locking when power is off, and the three driving feet adopt high hardness The wear-resistant ceramic ball with high wear resistance is in contact with the pre-tightening mechanism, which will greatly increase the service life of the motor.

(3) The utility model has a simple overall structure, improves the assembly efficiency of the motor, and is easy to realize batch production.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

Fig. 1 is the top view of the utility model;

Fig. 2 is a side view of the utility model.

Detailed ways

Example:

Please refer to FIG. 1 and FIG. 2 . In a preferred embodiment, a differential rotary piezoelectric stepper motor includes a drive assembly 1 , a mover 2 , a pretension mechanism 3 and a base 4 .

In a specific structure, the pre-tensioning mechanism 3 includes a rotating shaft 31 fixedly connected to the base, the mover 2 is fixedly connected to the rotating shaft 31, one end of the driving assembly 1 is connected to the base 4, and the other end is passed through The pre-tensioning mechanism 3 hugs the mover 2 tightly.

Specifically, the drive assembly 1 includes a first drive foot A, a second drive foot B, and a third drive foot C distributed at equal intervals in a ring around the rotating shaft. One end of the first drive foot A is connected to the base 4 The other end is tightly connected to the mover 2 through the pretension mechanism 3; one end of the second driving foot B is firmly connected to the base 4, and the other end is tightly embraced by the pretension mechanism 3. The mover 2; one end of the third driving foot C is firmly connected to the base 4, and the other end hugs the mover 2 tightly through the pre-tensioning mechanism 3.

The first driving foot A, the second driving foot B and the third driving foot C all have a displacement conversion mechanism 11, and the displacement conversion mechanism 11 is provided with a laminated piezoelectric ceramic 111, and through the laminated piezoelectric ceramic 11 The displacement conversion mechanism 11 is driven to rotate the mover 2 to drive the rotating shaft 31 to rotate.

In this embodiment, the first driving foot A, the second driving foot B and the third driving foot C also include wear-resistant ceramic balls 12, and the wear-resistant ceramic balls 12 are arranged on the displacement conversion mechanism 11 and the moving body. The displacement conversion mechanism 11 and the mover 2 are pressed against the displacement conversion mechanism 11 and the mover 2 up and down.

In this embodiment, the pretensioning mechanism 3 also includes a spring 32, a hex nut 33 and a metal ring (not shown in the figure), the hex nut 33 is arranged at one end of the rotating shaft 31, and the spring 32 is sleeved on On the rotating shaft 31 , the metal ring 34 is connected with the spring 32 . The displacement conversion mechanism of the first driving foot A is connected with the metal ring through wear-resistant ceramic balls, the displacement conversion mechanism of the second driving foot B is connected with the metal ring through wear-resistant ceramic balls; the third driving foot The displacement conversion mechanism of C is connected with the metal ring through wear-resistant ceramic balls, and the spring 32 is connected with the metal ring and can move on the rotating shaft.

The wear-resistant ceramic balls on the first driving foot A, the second driving foot B and the third driving foot C are spheres with the same shape and size.

The size of the preload provided by the pretension mechanism 3 can be adjusted by rotating the hex nut 33, and the metal ring can make the preload evenly applied to the three driving feet, and the pretension mechanism 3 compresses the The wear-resistant ceramic ball on the displacement conversion mechanism makes the first driving foot A, the second driving foot B, and the third driving foot C hug the mover 2 tightly through the displacement conversion mechanism, and its telescopic effect passes through the The displacement conversion mechanism is transmitted to the mover 2 to make the mover 2 rotate. Input a differential signal to the three driving feet to realize differential motion. During the whole driving process, the driving mode imitates the inertial friction driving; the differential motion can meet the requirements of large stroke.

The embodiment of the utility model utilizes the inverse piezoelectric effect of the laminated piezoelectric ceramics, the voltage applied to the laminated piezoelectric ceramics increases, and the laminated piezoelectric ceramics elongates; the voltage decreases, and the laminated piezoelectric ceramics retracts. Therefore, given a voltage signal, the telescopic movement of the laminated piezoelectric ceramic can be realized, and the axial displacement change can be realized, and the movement of the mover can be realized by transferring the displacement change to the mover through frictional motion. The movement range of a single laminated piezoelectric ceramic is very small, only tens of microns, and the friction force is also very small. Multiple laminated piezoelectric ceramics are mechanically connected in parallel and connected in series on the circuit. Given a differential drive signal control, the realization The stroke accumulation of the stepping drive can realize a wide range of driving; the friction force of a single drive is very limited, and the joint use of multiple driving feet can increase the friction force to achieve a large thrust output drive.

Further, the utility model uses three driving feet to realize differential drive control. Requirements for the normal operation of differential motion: the three driving feet are in contact with the mover in the form of surface contact, the contact material, contact area, contact method and pre-tightening force are exactly the same, and the driving friction of a single foot is smaller than that of the mover. Static friction force, the sum of the driving friction forces of the three driving legs is greater than the static friction force of the mover; the three driving legs move in sequence, and the mover stands still during this process; after the three driving legs are all stretched, they retract at the same time, at this time The total driving force of the mover is greater than the static friction force of the mover. Under the action of the total drive force, the mover rotates a step distance, and the three driving feet return to the original length in turn. At this time, the mover remains still under the action of inertia, and the above movement is repeated. , which can realize the continuous rotation and stepping motion of the mover.

The above is only a preferred embodiment of the utility model, so the scope of implementation of the utility model cannot be limited accordingly, that is, equivalent changes and modifications made according to the patent scope of the utility model and the contents of the specification should still belong to this utility model. within the scope of utility models.

Claims (6)

1. a kind of differential rotary piezoelectric stepper motor, it is characterised in that: including driving assembly, mover, pre-tightening mechanism and pedestal, institute Stating pre-tightening mechanism includes the shaft affixed with the pedestal, and the mover is fixedly connected with the shaft, the driving component one end The pedestal is connected, the other end hugs the mover by the pre-tightening mechanism；

The driving component includes the first driving foot, the second driving foot and third driving foot being distributed in a ring around shaft, should First driving foot, the second driving foot and third driving foot all have displacement converted mechanism, and the displacement converted mechanism is equipped with folded It is laminated electroceramics, and makes the mover rotation to drive described turn by displacement converted mechanism described in the stacked piezoelectric ceramic driving Axis rotation.

2. a kind of differential rotary piezoelectric stepper motor according to claim 1, it is characterised in that: the first driving foot, Second driving foot and third driving foot also all include wearable ceramic ball, and the wearable ceramic ball is arranged in the displacement converted mechanism Between mover and up and down displacement converted mechanism and mover described in contact.

3. a kind of differential rotary piezoelectric stepper motor according to claim 1, it is characterised in that: the pre-tightening mechanism also wraps Include spring, metal ring and the hex nut that shaft one end is set, the spring is set in shaft, the metal ring with The spring is connected.

4. a kind of differential rotary piezoelectric stepper motor according to claim 1, it is characterised in that: the first driving foot, Second driving foot and third drive boll of foot girth spaced set around the shaft.

5. a kind of differential rotary piezoelectric stepper motor according to claim 1, it is characterised in that: the mover is wear-resisting gold Belong to disk.

6. a kind of differential rotary piezoelectric stepper motor according to claim 2, it is characterised in that: the first driving foot, The wearable ceramic ball of second driving foot and third driving foot is the identical sphere of shape size.