JPH1190867A - Micromanipulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sufficiently large movable range though having high resolving power. SOLUTION: In a micro-manipulator using a micro parallel link mechanism having six freedom degrees, each link has a pipe 24, piezoelectric element 25, movable piece 26 having an elastic spring leg 39 provided in one end of this piezoelectric element, elastic material 38, and a slider 27, and a direct acting actuator is provided, which drives the slider 27 by the movable piece 26 moved by rapid deformation of the piezoelectric element 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a micromachine,
Assembly, welding, etc. of micro components such as optical communication components and semiconductors
The present invention relates to a micromanipulator with a microparallel link mechanism used in the field of micromachining, a stage of a microscope, etc. and in the field of biotechnology for cell manipulation.

[0002]

2. Description of the Related Art At present, in optical communication and semiconductor related fields,
There is a demand for a micromanipulator with a high degree of freedom and high precision, which is small and has a movable range on the order of [mm (millimeter)] for a microassembly apparatus for assembling micro optical components and semiconductors. In particular, such a micromanipulator can (1) have a resolution of the order of several tens [nm (nanometers)] and can take a long stroke of 1 [mm] or more. (2) Assemble work under a microscope. There is a strong demand for two points that can be miniaturized in order to perform this.

That is, in the fine work, high-precision, multi-degree-of-freedom positioning is required. For this reason, a parallel link type manipulator has been proposed which is configured to be expandable and contractible by piezoelectric elements provided on each of six links. .

Japanese Patent Laid-Open Publication No. Hei 6-170761 discloses a micro parallel link mechanism of the same type, and FIG. 7 illustrates such a micro manipulator. Here, the main body of the parallel link mechanism includes a movable plate 11, a fixed plate 12, and six links 13, 13,. A hand 14 is provided on the movable plate 11.

A link type piezoelectric element 15 and a strain gauge 16 are incorporated in each of the links 13, 13,... So that the stroke of the link type piezoelectric element 15 changes with the expansion and contraction operation of the link type piezoelectric element 15. .

However, the amount of stroke is detected by the strain gauge 16, and the stroke of each link 13, 13,... Relative motion of a total of six degrees of freedom (three degrees of freedom) can be performed.

According to such a link connection system, the stroke amount of each link 13, 13,... Is adjusted by the laminated piezoelectric element 15 as an actuator,
The relative position and posture of the upper movable plate 11 with respect to the lower fixed plate 12 can be controlled.

[0008]

However, in the parallel link mechanism shown in FIG. 7, since the expansion / contraction operation of the laminated piezoelectric element 15 is used as it is for the expansion / contraction of the link 13, the resolution in control is very high. On the other hand, the maximum operation stroke, that is, the displacement amount is as very small as 8 [μm], and as a result, the movable range of the parallel link mechanism itself is reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a parallel link having six degrees of freedom which can have a sufficiently large movable range while having high resolution. An object of the present invention is to provide a micromanipulator using a mechanism.

[0010]

According to the first aspect of the present invention,
In a micromanipulator using a micro parallel link mechanism having six degrees of freedom, each link has a pipe, a piezoelectric element, a movable element having a spring leg provided at one end of the piezoelectric element, an elastic material, and a slider. A linear motion actuator is provided in which the slider is driven by the mover moved by rapid deformation of the piezoelectric element.

As a result of such a configuration, the linear motion actuator constituting the link connecting the movable plate and the fixed plate is small, while having a high resolution, without being restricted by the movable range. The entire manipulator can be reduced in size.

According to a second aspect of the present invention, in the first aspect of the present invention, an inertial body is provided at the other end of the piezoelectric element where no mover is provided. As a result of such a configuration, in addition to the effect of the first aspect of the present invention, the amount of inertia directly related to the amount of movement of the mover can be variably set. The step amount and the expansion / contraction speed can be arbitrarily variably set.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment) A parallel link type micromanipulator according to a first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the overall configuration of the apparatus, which comprises a movable plate 21 on which a hand 20 is mounted and fixed, a fixed plate 22, and six links 23 connecting these two. ing.

Each of the links 23, 23,... Has a laminated piezoelectric element 25 and a movable element 26 which will be described later incorporated in a pipe 24, and is movable with a rapid expansion and contraction operation of the laminated piezoelectric element 25. The stroke is changed by the child 26.

FIG. 2 is a sectional view exemplifying a specific structure of the link 23. In the pipe 24, a slider 27 driven by a movable element 26 moved by a laminated piezoelectric element 25 extends along the axial direction of the pipe 24. It has a sliding structure,
The slider 27 is connected to the movable plate 21 not shown here via a connecting rod 28 and a ball joint 29,
4 is connected to a fixing plate 22 not shown here via a connecting rod 30 and a ball joint 31.

The ball joint 29 is pressurized in a housing 34 fixed to the movable plate 21 by a pressurizing plate 32 and a pressurizing spring 33, so that the mounting angle with the movable plate 21 can be changed smoothly. Similarly, the ball joint 31 is fixed to the fixed plate 22 by the pressurized plate 35 and the pressurized spring 36.
Is pressurized in a housing 37 fixed to the fixing plate 22 so that the mounting angle with the fixing plate 22 can be changed smoothly.

An elastic material 3 is provided on one end surface of the slider 27.
8 and a flat plate-like movable element 26 and this movable element 2
A laminated piezoelectric element 25 having one end inserted into the center hole of 6 is provided, and an elastic spring leg 39 is provided on the movable element 26 so as to cover the laminated piezoelectric element 25. Constitute a fulcrum that gives a frictional force by elasticity.

However, the pipe 24 has a diameter of, for example, 2 [mm], and has the slider 2 therein.
7, a linear actuator composed of an elastic member 38, a movable element 26, a laminated piezoelectric element 25, and an elastic spring leg 39 is housed therein. It is held by static friction with the surface. In addition, the elastic member 38, the mover 26, the multilayer piezoelectric element 2
5 and the elastic spring leg 39 are integrated.

However, when the multilayer piezoelectric element 25 is rapidly extended, an impulsive inertial force is generated, and the movable element 26 slides in the pipe 24 overcoming the static friction force. Therefore, when the laminated piezoelectric element 25 is gently contracted, the movable element 26 stops sliding and the position is fixed in the pipe 24 by the static friction force.

On the contrary, the movable element 26 can be moved in the opposite direction by causing the multilayer piezoelectric element 25 to contract rapidly after being rapidly contracted. Hereinafter, the operation of the linear motion actuator will be described in detail.

When a trapezoidal wave voltage is applied to the laminated piezoelectric element 25 as shown in FIG.
At the timing of III, the laminated piezoelectric element 25 rapidly expands. At this time, the movable element 26 and the multilayer piezoelectric element 25 rapidly move in opposite directions, and at the same time, the multilayer piezoelectric element 2
5 generates an impact force. This laminated piezoelectric element 25
The impact force generated by this is transmitted to the mover 26 to drive the mover 26 overcoming the static friction force. Thus, the mover 26 pushes and moves the slider 27 via the elastic member 38 so as to strike.

Thereafter, in the timing sections II and IV in the figure, the voltage applied to the multilayer piezoelectric element 25 is gradually reduced, and the length of the multilayer piezoelectric element 25 gradually shrinks. The movement of the mover 26 is prevented by the frictional force between the outer peripheral surface of the piezoelectric element 25 and the inner peripheral surface of the pipe 24, and only the multilayer piezoelectric element 25 itself is pulled back.

By repeating such a process, the slider 27 slides in the pipe 24, and the length of the link 23 is extended. That is, the mover 26 is held by friction with the inner peripheral surface of the pipe 24, starts moving when the inertial force exceeds the maximum static friction force, and stops when the inertia force falls below the dynamic friction force.

Such a link 23 is located between the movable plate 21 and the fixed plate 22, and as shown in FIG. 2, the slider 27 is connected to the pressurizing plate 32 The pipe 24 is pressurized by the pressurizing spring 33, and similarly, the pipe 24 is pressurized by the pressurizing plate 35 and the pressurizing spring 36 in the housing 37 by the ball joint 31 via the connecting rod 30 to be rotatable. Since they are connected, a structure having six degrees of freedom can be realized with one link 23.

Further, instead of the trapezoidal wave voltage as shown in FIG. 3, a full-wave rectified wave voltage as shown in FIG. 4 can be applied. In this case, the output, link 2
The force of expansion and contraction at 3 can be further increased.

With the structure of the link 23 according to the first embodiment as described above, the linear actuator of the desired link 23 is driven to drive the link 23
Is expanded or contracted, the movable plate 21 is controlled in six degrees of freedom in position and posture in accordance with the amount of expansion and contraction of each of the links 23, 23,. It will be.

The linear motion actuator is not limited in its movable range, and can be set sufficiently long in accordance with the length of the pipe 24. In addition, since the configuration of the linear motion actuator itself is extremely small, it is possible to set the working range to be much wider while reducing the size of the entire device as compared with a conventional manipulator of a parallel link mechanism driven by expansion and contraction of a piezoelectric element. . Therefore, it can be easily realized as, for example, a micromanipulator that performs an operation of finely assembling a minute object under a microscope or a manipulation.

(Second Embodiment) A parallel link type micromanipulator according to a second embodiment of the present invention will be described below with reference to the drawings.

Since the entire structure is the same as that described with reference to FIG. 1, the same portions are denoted by the same reference numerals, and their illustration and description are omitted. further,
The specific configuration of the link 23 is basically the same as shown in FIG. 5, and therefore, the same portions are denoted by the same reference numerals and description thereof will be omitted.

The movable element 2 of the laminated piezoelectric element 25
The inertial body 40 is fixedly arranged on the other end side where the 6 is not provided.
The inertial body 40 is provided to increase the impact force generated when the multilayer piezoelectric element 25 is rapidly expanded by the applied voltage, and thereby, the inertia directly related to the moving amount of the movable element 26 is provided. The amount can be set variably.
Therefore, the extension / contraction step amount and the extension / contraction speed of the linear motion actuator can be arbitrarily variably set.

Hereinafter, the operation of the linear motion actuator will be described in detail. As shown in FIG. 6, when a trapezoidal wave voltage is applied to the multilayer piezoelectric element 25, the multilayer piezoelectric element 25 rapidly expands at timings V and VII when the voltage in the figure rises. At this time, the mover 26 and the multilayer piezoelectric element 25 rapidly move in opposite directions, and at the same time, the inertia 4
An impact force is generated according to the laminated piezoelectric element 25 provided with 0. The impact force generated by the laminated piezoelectric element 25 is obtained by adding the mass of the inertial body 40 and transmitted to the mover 26, and easily drives the mover 26 by overcoming the static friction force. Thereby, the mover 26 pushes and moves the slider 27 via the elastic member 38 so as to hit the slider 27 strongly.

Thereafter, in the timing sections VI and VIII in the figure, the voltage applied to the multilayer piezoelectric element 25 is gradually reduced, and the length of the multilayer piezoelectric element 25 contracts gradually. Piezoelectric element 25 outer peripheral surface and pipe 2
The movement of the mover 26 is prevented by the frictional force with the inner peripheral surface of the piezoelectric element 4, and only the multilayer piezoelectric element 25 itself is pulled back.

By repeating such a process, the slider 27 slides in the pipe 24, and the length of the link 23 is extended. That is, the mover 26 is held by friction with the inner peripheral surface of the pipe 24, starts moving when the inertial force exceeds the maximum static friction force, and stops when the inertia force falls below the dynamic friction force.

On the contrary, the movable element 26 can be moved in the opposite direction by causing the multilayer piezoelectric element 25 to contract rapidly after being rapidly contracted. Since the inertial force takes into account the mass of the inertial body 40, the amount of sliding of the inertial body 40 at one time, that is, the amount of expansion / contraction step, compared to the case of the configuration shown in FIG. Can be increased, and as a result, the expansion / contraction speed when repeatedly driven can be increased.

Therefore, by changing the mass of the inertial body 40, the expansion / contraction speed of the linear motion actuator can be arbitrarily variably set. It should be noted that the present invention is not limited to the first and second embodiments, but can be variously modified and implemented without departing from the gist thereof.

[0037]

According to the structure of the first aspect of the present invention, while having a high resolution, there is no restriction on the movable range, and a direct link for connecting the movable plate and the fixed plate is formed. Since the dynamic actuator is small, the entire manipulator can be downsized.

According to the structure of the second aspect of the invention, in addition to the effect of the first aspect of the invention, the amount of inertia directly related to the movement of the movable element can be variably set. As a result, the expansion / contraction step amount and the expansion / contraction speed of the linear motion actuator can be arbitrarily variably set.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an overall configuration according to a first embodiment of the present invention.

FIG. 2 is an exemplary view showing a cross-sectional structure of the link according to the embodiment;

FIG. 3 is a diagram showing a voltage waveform applied to the laminated piezoelectric element and the operation of the linear actuator according to the embodiment.

FIG. 4 is a view exemplifying another applied voltage waveform to the multilayer piezoelectric element according to the embodiment;

FIG. 5 is a diagram showing a cross-sectional structure of a link according to a second embodiment of the present invention.

FIG. 6 is a diagram showing a voltage waveform applied to the laminated piezoelectric element and the operation of the linear actuator according to the embodiment.

FIG. 7 is a perspective view showing a configuration of a micromanipulator using a general parallel link mechanism.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Movable plate 12 ... Fixed plate 13 ... Link 14 ... Hand 15 ... Laminated piezoelectric element 16 ... Strain gauge 20 ... Hand 21 ... Movable plate 22 ... Fixed plate 23 ... Link 24 ... Pipe 25 ... Laminated piezoelectric element 26 ... Movable Element 27 ... Slider 28,30 ... Connecting rod 29,31 ... Ball joint 32,35 ... Pressure plate 33,36 ... Pressure spring 34,37 ... Housing 38 ... Elastic material 39 ... Elastic spring leg 40 ... Inertial body

Claims (2)

[Claims] In a micromanipulator using a micro-parallel link mechanism having six degrees of freedom, each link includes a pipe, a piezoelectric element, a movable element having a spring leg provided at one end of the piezoelectric element, an elastic material, and a slider. A micromanipulator comprising: a linear motion actuator having the slider driven by the mover moved by rapid deformation of the piezoelectric element. 2. The micromanipulator according to claim 1, wherein an inertial body is provided at the other end of the piezoelectric element where no mover is provided.