CN104377987B - Clamping type piezoelectric motor - Google Patents

Abstract

The invention discloses a clamping piezoelectric motor. The motor is sequentially composed of a first clamping unit, a driving unit and a second clamping unit from left to right, wherein the two clamping units are pressed by a guide rail and a pre-pressing mechanism. Tightly fixed on the guide rail, the two clamp units output the displacement perpendicular to the direction of the fixed guide rail, and the output of the drive unit is parallel to the direction of the fixed guide rail. The present invention adopts the piezoelectric stack drive, realizes the relationship between the first clamping unit and the second clamping unit driving foot and the guide rail through the shrinkage and elongation of the piezoelectric stack; on the move. In addition to the characteristics of the general piezoelectric stepping motor, the present invention also has a self-locking function, and one end of the guide rail can be adjusted, which reduces the requirements for the machining accuracy and assembly accuracy of the motor, and the whole mechanism of the motor is equivalent to a whole , increasing the smoothness of operation.

Description

A clamped piezoelectric motor

technical field

The utility model belongs to the technical field of piezoelectric precision actuation applications, in particular to a clamping piezoelectric linear motor.

Background technique

In recent years, with the rapid development of micro/nano technology, research in many engineering and technical fields urgently needs submicron and micro/nano ultra-precision drives. The traditional stepper motor has a low power-to-weight ratio, and after the motor runs at high speed, it needs a reduction device to change the speed, resulting in a complicated transmission system and a cumbersome structure. With the development of science and technology, various functional materials have been developed. Among them, piezoelectric ceramics (PZT) have attracted extensive attention in the research of piezoelectric precision actuators due to their relatively superior performance, and have been applied in many fields. .

At present, the research on piezoelectric precision drives at home and abroad has made some progress, and various motors have been developed. Among them, the inchworm piezoelectric actuator adopts the principle of bionics and adopts the motion form of "clamp-drive-clamp". It has the advantages of high resolution, large output force, large output rigidity, and no electromagnetic interference. It has been well received at home and abroad. Research extensively.

The application number is 201110058690.2, which is called "Multi-leg Clamping Piezoelectric Motor", which discloses a method of installing auxiliary clamping mechanisms at both ends, which solves the problem of non-parallel guide rails and guide rail surfaces caused by guide rail processing and assembly errors. The problem of motor jamming or poor walking caused by local inequality; however, it uses multiple sets of driving feet and uses springs and stacks to achieve walking, and the structure is complex.

Utility model content

Technical problems to be solved:

The purpose of the utility model is to provide a clamp-type piezoelectric motor with good stability, large output force, high efficiency, long life, high resolution, relatively low processing requirements and wider application range in view of the defects of the existing technology. .

Technical solutions:

In order to achieve the above functions, the utility model provides a clamping piezoelectric motor including a first clamping mechanism 1, a driving mechanism, and a second clamping mechanism 11 connected in sequence, and the clamping mechanisms 1 and 11 are set on the guide rail Inside, it is characterized in that: the clamping mechanisms 1 and 11 adopt a displacement amplification structure, and piezoelectric ceramic stacks 3 and 10 are arranged inside.

Each clamping mechanism has a U-shaped structure on the outside and a rectangular frame inside, and the piezoelectric ceramic stacks 3 and 10 are arranged in the rectangular frame, and each group of piezoelectric ceramic stacks 3 and 10 includes piezoelectric ceramic sheets and support blocks. And the extension spring, the piezoelectric ceramic stack support block is next to the piezoelectric ceramic stack piezoelectric ceramic sheet, the piezoelectric ceramic stack support blocks on the outside are respectively fixed on the inner surface of the rectangular frame by screws, and the piezoelectric ceramic stack support blocks on the inside are respectively fixed on the inner surface of the rectangular frame. The ceramic stack support block is connected to the drive unit; the piezoelectric ceramic stack tension springs are arranged in sequence on the outer surface of the piezoelectric ceramic stack piezoelectric ceramic sheets for pre-tightening the piezoelectric ceramic stack piezoelectric ceramic sheets.

The drive mechanism includes a piezoelectric ceramic sheet, a support block, a tension spring and a flexible foot, and the drive mechanism support block is next to the drive mechanism piezoelectric ceramic sheet; the drive mechanism extension spring is arranged in sequence on the drive mechanism piezoelectric ceramic sheet The outer surface of the drive mechanism is used to pre-tighten the piezoelectric ceramic sheet; the flexible foot is arranged on the outer side of the drive mechanism support block, and is fixedly connected with the inner piezoelectric ceramic stack support block.

Holes are opened on the lower surface of the U-shaped structure, and small balls are arranged in the holes.

A hole is opened at the position where the outer piezoelectric ceramic stack support block is connected with the screw, and a small ball is arranged in the hole.

The two feet of the U-shaped structure are used as driving feet, and the four corners of the rectangular frame are designed as elliptical flexible hinges. The two long sides of the U-shaped structure are also connected by elliptical flexible hinges. The stacking is elongated, so that the distance between the two sides of the rectangular structure is extended, so that the distance between the other two sides is shortened, and the distance between the two sides of the U-shaped structure is shortened.

Beneficial effect:

The clamping piezoelectric motor of the utility model has a clamping mechanism with an amplification effect. During the assembly process of the piezoelectric stepping precision driver, there must be an error in the distance between the two ends of the guide rail. When the non-parallelism of the guide rail is so large that the distance change △L of the guide rail is greater than the gap between the mover and the guide rail, the mover will appear. Stuck, or walking is not smooth, because the laminated piezoelectric stack has limited elongation in the guide rail, only a few microns, so the gap must be smaller than the elongation of the laminated piezoelectric stack. The utility model uses a clamping mechanism to convert the displacement of the piezoelectric stack parallel to the guide rail into the displacement of the driving foot perpendicular to the guide rail. Through its specific structure, the displacement of the piezoelectric stack is amplified, thereby avoiding the motor jam to a certain extent. In addition, a groove is processed on one of the driving feet of the clamping mechanism, and a small plastic ball is placed, so that the sliding friction of the driving foot during the movement is converted into rolling friction, to a certain extent Make the motor run more smoothly.

Description of drawings

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

Fig. 1 is the structural schematic diagram of the clamp type piezoelectric motor provided by the utility model;

Fig. 2 is the timing sequence of the power supply signal used for driving the clamped piezoelectric motor provided by the utility model;

Figure 3 The running process of the motor, (a) is the state of the motor at time t1, (b) is the state of the motor at time t2, (c) is the state of the motor at time t3, (d) is the state of the motor at time t4, (e) is the state of the motor at time t5 state.

Among them, 1-first clamping mechanism; 2-support block; 3, 7-piezoelectric ceramic stack; 4-tension spring; 5-guide rail; 6-flexible foot; 8-plastic ball; 9-screw; 10 - the third piezoelectric stack; 11 - the second clamping mechanism.

detailed description

The utility model provides a clamping piezoelectric motor. In order to make the purpose, technical solution and effect of the utility model clearer and clearer, the utility model is further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific implementation described here is only used to explain the utility model, and is not intended to limit the utility model.

As shown in Figure 1, a clamping piezoelectric motor includes a first clamping mechanism 1, a driving mechanism, and a second clamping mechanism 11 connected in sequence, and the clamping mechanisms 1 and 11 are set in a guide rail, and its characteristics That is: the clamping mechanisms 1 and 11 adopt a displacement amplification structure, and piezoelectric ceramic stacks 3 and 10 are arranged inside.

Each clamping mechanism has a U-shaped structure on the outside and a rectangular frame inside, and the electric ceramic stacks 2 and 10 are arranged in the rectangular frame, and each group of piezoelectric ceramic stacks 3 and 10 includes piezoelectric ceramic sheets and support blocks 2 And the extension spring 4, the piezoelectric ceramic stack support block 2 is next to the piezoelectric ceramic stack piezoelectric ceramic sheet, the piezoelectric ceramic stack support block 2 on the outside is respectively fixed on the inner surface of the rectangular frame by screws, and the inner side The piezoceramic stack support block 2 is connected to the drive unit; the piezoceramic stack tension springs 4 are arranged on the outer surface of the piezoceramic stack piezoceramic sheet in order for pre-tightening the piezoceramic stack Piezoelectric ceramic discs.

The drive mechanism includes a piezoelectric ceramic sheet, a support block, a tension spring and a flexible foot 6, and the drive mechanism support block is next to the drive mechanism piezoelectric ceramic sheet; the drive mechanism extension spring is arranged in sequence on the drive mechanism piezoelectric ceramic The outer surface of the sheet is used to pre-tighten the piezoelectric ceramic sheet of the driving mechanism; the flexible foot 6 is arranged on the outer side of the supporting block of the driving mechanism, and is fixedly connected with the piezoelectric ceramic stack supporting block on the inner side.

A hole is opened on the lower surface of the U-shaped structure, and a small ball 8 is arranged in the hole.

A hole is opened at the position where the outer piezoelectric ceramic stack support block is connected with the screw, and a small ball is arranged in the hole.

The two feet of the U-shaped structure are used as driving feet, and the four corners of the rectangular frame are designed as elliptical flexible hinges. The two long sides of the U-shaped structure are also connected by elliptical flexible hinges. The stacking is elongated, so that the distance between the two sides of the rectangular structure is extended, so that the distance between the other two sides is shortened, and the distance between the two sides of the U-shaped structure is shortened.

Taking the linear mover moving to the right in the guide rail as an example, the motion principle of the actuator is introduced below: initially the mover is in the state of being pressed by the pre-pressed guide rail → the piezoelectric stack 10 is energized and elongated, and the second clamping mechanism 11 is out of contact Guide rail → Piezoelectric stack 7 elongates and pushes the second clamping mechanism 11 to move a small displacement to the right → Piezoelectric stack 10 is powered off and retracts, second clamping mechanism 11 contacts the guide rail → Piezoelectric stack 3 is energized and elongated , the first clamping mechanism 1 is out of contact with the guide rail → the piezoelectric stack 7 is powered off and shrinks, and the clamping mechanism 1 moves to the right by a slight displacement → ... and so on, so that each cycle moves one step to the right. Like this mover just can walk along guide rail to the right step by step. From the perspective of the motor running process, there is always more than one clamping mechanism touching the guide rail. When the motors have different voltages, the two clamping mechanisms contact the guide rail at the same time, and both have a certain pressure, so the motor has a self-locking function.

Generally, the displacement of the direct output of the laminated piezoelectric stack is very small, which is at the micro/nano level, so the displacement amplification structure is used in the clamping mechanism, and the displacement of the piezoelectric stack parallel to the guide rail is converted into the vertical displacement of the driving foot by using the clamping mechanism. Due to the displacement of the guide rail, through its specific structure, the displacement of the piezoelectric stack is amplified, so that the driving foot part of the motor clamp unit can ideally realize the alternate process of pushing away from the guide rail and detaching from the guide rail, avoiding to a certain extent The phenomenon that the motor is stuck or the movement is not smooth. A driving foot of the clamp mechanism has a groove processed and a small plastic ball is placed, so that the sliding friction of the driving foot during movement is converted into rolling friction, which makes the motor run more smoothly to a certain extent.

The drive unit does not use an amplification structure, and directly uses the stack to output displacement. One end of the two piezoelectric ceramic stacking mechanisms is supported by a screw in the rectangular structure of the two clamping units, and the other end is respectively connected to the driving unit by a stud.

A rectangular signal with a certain timing relationship is applied to the corresponding laminated piezoelectric stack, as shown in Figure 2, piezoelectric stacks 3, 7, and 10 respectively correspond to signal 1, signal 2, and signal 3 in Figure 2, and the figure shows Two periods of the signal, t0 to T is a period of the signal, Figure 3 shows the state of the motor corresponding to the moment marked in Figure 2. After the signal is amplified, it can stimulate the expansion and contraction of the laminated piezoelectric stack, so that the clamping mechanism and the drive unit move with a certain timing difference, thereby forming the telescopic walking of the mover along the direction of the guide rail.

It can be understood that those skilled in the art can make equivalent replacements or changes according to the technical solution of the utility model and its utility model concept, and all these changes or replacements should belong to the appended claims of the utility model protected range.

Claims (5)

1. a kind of clamp formula piezoelectric motor, including the first clamping institution (1) being sequentially connected, drive mechanism, the second clamping institution (11), two clamping institutions be fixed on guide rail by precompressed mechanism it is characterised in that: described clamping institution (1,11) adopts Displacement equations structures, are internally provided with piezoelectric element (1,10)；

Each clamping institution (1,11) is provided at an outer portion with u-shaped inside configuration and is provided with rectangular frame, and piezoelectric element (3,10) sets Put in rectangular frame, every group of piezoelectric element (3,10) includes piezoelectric ceramic piece, support block and extension spring, described piezoelectricity pottery Porcelain stacks support block and is close to piezoelectric element piezoelectric ceramic piece, and the piezoelectric element support block in outside passes through screw respectively It is fixed on the inner surface of rectangular frame, the piezoelectric element support block of inner side is connected on driver element；Described piezoelectric ceramics Stack the outer surface that extension spring is sequentially arranged in piezoelectric element piezoelectric ceramic piece, for pretension piezoelectric element piezoelectric ceramics Piece.

2. a kind of clamp formula piezoelectric motor according to claim 1 it is characterised in that: described drive mechanism include piezoelectricity pottery Ceramics, support block, extension spring and flexible foot, described drive mechanism support block is close to drive mechanism piezoelectric ceramic piece；Described drive Motivation structure extension spring is sequentially arranged in the outer surface of drive mechanism piezoelectric ceramic piece, for pretension drive mechanism piezoelectric ceramic piece；Institute State the outside that flexible foot is arranged on drive mechanism support block, be fixedly connected with the piezoelectric element support block of inner side.

3. a kind of clamp formula piezoelectric motor according to claim 1 it is characterised in that: in the lower surface of described u-shaped structure Have hole, in the hole is provided with bead.

4. a kind of clamp formula piezoelectric motor according to claim 1 it is characterised in that: piezoelectric ceramics in described outside is folded Heap support block and mode connects for screw position have hole, and in the hole is provided with bead.

5. according to Claims 1-4 any one clamp formula piezoelectric motor it is characterised in that: the two of described u-shaped structure As driving foot, four angles of rectangular frame are designed as oval flexible hinge to foot, its two long while long with two of u-shaped structure It is connected using oval flexible hinge, by its internal piezoelectric stack elongation, so that rectangular configuration two back gauge is extended, so that separately Outer both sides Distance Shortened, and then so that u-shaped structure two back gauge is shunk.