JPH051992Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention is a piezoelectric micro-displacement actuator that is used, for example, to transmit micro-displacement to a moving table for precise positioning control of the table. It is related to.

[Prior Art] Fig. 2 is a partially cutaway front view showing an example of a conventional piezoelectric micro-displacement actuator. Electrostrictive element made of 3
a and 3b are blocks provided at both ends of the electrostrictive element 2; 7 is a holding plate;
The electrostrictive element 2 is fixed to the holding plate 7 by tightening the bolt 8 b.

Next, the operation of the above configuration will be explained.

When a voltage is applied to the electrostrictive element 2, the electrostrictive element 2 generates a minute displacement in the direction of arrow B in FIG. 2 in accordance with the magnitude of the applied voltage. This minute displacement is transmitted to a working table or the like via the block 3a.

[Problems to be solved by the invention] The above-described multilayer electrostrictive element has the following general properties when subjected to an external force. That is, since the piezoelectric ceramic is laminated and bonded in the axial direction, it is strong against compressive loads in the axial direction, but when subjected to shear force, damage such as peeling of the adhesive layer is likely to occur.

In the piezoelectric micro-displacement actuator having such properties, the conventional one described above has a second
When shearing force is applied in the direction of arrow F in the figure, there is a drawback that the electrostrictive element 2 is damaged, such as peeling of the adhesive layer.

This invention was made to solve the above-mentioned problems, and its purpose is to provide a piezoelectric micro-displacement actuator that can reliably and sufficiently protect against shear forces.

[Means for solving the problem] The piezoelectric micro-displacement actuator according to this invention has a fixed end block and an output end block fixed to both ends of a columnar electrostrictive element made by laminating and bonding a large number of piezoelectric ceramics. an electrostrictive element block, a prop base having a pedestal and a base at both ends of a column made of a material having high rigidity in the axial direction and elasticity in the shear direction, and the electrostrictive element block and the prop base. The device is characterized by comprising a case consisting of a base and a cover for storing the.

The strut in the strut pedestal is disposed coaxially with the electrostrictive element block, and fixes the fixed end block to the pedestal and fixes the base to the base.

A guide hole is formed in the cover, through which the other block is slidably inserted in the axial direction.

[Effect]

When an external force in the shearing direction is applied to the output end block, the support of the support base is deflected within the range of the minute play formed between the block and the guide hole, and the shear force acting on the electrostrictive element is reduced. is absorbed by the deflection.

〔Example〕

An embodiment of this invention will be described below based on the drawings.

FIG. 1 is a partially cutaway front view showing a piezoelectric micro-displacement actuator according to an embodiment of this invention.

In the figure, at both ends of a columnar electrostrictive element 2 formed by laminating and bonding a large number of piezoelectric ceramics 1,
An electrostrictive element block 10 is constructed by fixing the output end block 3a and the fixed end block 3b.

Reference numeral 5 denotes a support post, and the support support 5 is made of a material having high rigidity in the axial direction and a small elastic modulus in the shear direction, and is formed in a substantially E-shape.

That is, the support 5 has a pedestal 5b and a base 5c at both ends of the support 5a, the support 5a is arranged coaxially with the electrostrictive element block 10, and the output end block is attached to the pedestal 5b. 3a is fixed with a bolt 8, and a bolt 9 protruding from the base 5c is screwed into the bottom 11a of a bottomed cylindrical base 11.

A cover 4 is fixed to the opening of the base 11,
A case 6 is configured to house the electrostrictive element block 10 and the support column 5.

A guide hole 4a passing through the cover 4 from the inside to the outside is formed, and the block 3a is inserted therethrough so as to be slidable in the axial direction (direction of arrow A).

Next, the operation of the above configuration will be explained.

Now, when a voltage is applied to the electrostrictive element 2, this element 2 generates a minute displacement in the direction of arrow A in accordance with the magnitude of the applied voltage, and this minute displacement moves through the output end block 3a for work. transmitted to a table, etc.

During this transmission process, when an external force is applied to the block 3a in the shearing direction shown by the arrow F, the support 5 is moved within the range of minute play formed between the block 3a and its guide hole 4a. The pillar 5a is bent, and the shearing force acting on the electrostrictive element 2 is absorbed.

Therefore, no excessive shearing force is applied to the electrostrictive element 2, and damage such as peeling of the adhesive layer between the laminated piezoelectric ceramics 1 is prevented.

Furthermore, the bending action of the support column 5a can also absorb installation errors when inserting the block 3a into the guide hole 4a.

[Effects of the invention] As described above, according to this invention, it is possible to prevent excessive shearing force from being applied to the laminated electrostrictive element and reliably prevent damage to the electrostrictive element such as peeling of the adhesive layer. can. This makes it possible to use the laminated electrostrictive element even under conditions where shear force is applied, thereby expanding its uses.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway front view of a holding mechanism for a laminated electrostrictive element according to an embodiment of the invention, and FIG. 2 is a partially cutaway front view of a conventional holding mechanism for a laminated electrostrictive element. . DESCRIPTION OF SYMBOLS 1... Piezoelectric ceramic, 2... Laminated electrostrictive element, 3a... Output end block, 3b... Fixed end block, 4... Cover, 4a... Guide hole, 5...
... Prop stand, 5a... Prop, 5b... Pedestal, 5c...
...Base, 6...Case, 10...Electrostrictive element block, 11...Base. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] A piezoelectric minute displacement actuator comprising an electrostrictive element block 10, a support base 5, and a case 6, wherein the electrostrictive element block 10 includes an electrostrictive element 2 and a fixed end block 3b. and an output end block 3a, the electrostrictive element 2 is formed into a columnar shape by laminating a large number of piezoelectric ceramics 1, and a fixed end block 3b is fixed to one end of the column, and an output end block 3a is fixed to the other end. The support column 5 is formed of a support column 5a, a pedestal 5b, and a base 5c, and the support column 5a is made of a material having high rigidity in the axial direction and elasticity in the shear direction,
A pedestal 5b is fixed to one end, and a base 5c is fixed to the other end.The case 6 is formed of a base 11 and a cover 4, the cover 4 has a guide hole 4a, and the electrostrictive element block is fixed to the case 6. 10 and a support stand 5, the support stand 5 has an electrostrictive element block 10 in which the support support 5a
The base 5c is fixed to the base 11, and the electrostrictive element block 10 is arranged coaxially with the fixed end block 3b.
is fixed to a pedestal 5b, and an output end block 3a is inserted into a guide hole 4a so as to be slidable in the axial direction through a small gap.