JPH05304323A - Displacement enlargement mechanism - Google Patents

Abstract

PURPOSE:To protect the other piezoelectric element against breakdown by additionally disposing a displacement regulating section between two piezoelectric elements and setting the stiffness at the displacement regulating section such that an angular displacement takes place at a displacement part, with hinges at the opposite ends of the other piezoelectric element as fulcrums, when a voltage is applied only on one piezoelectric element. CONSTITUTION:A rod type displacement regulating section 4 is disposed between piezoelectric elements 2, 3 while being secured through hinge sections 4a, 4b at the opposite ends to the surface 1a of a displacement part 1 and the surface 5a of a fixed part 5. The piezoelectric element 3 elongates upon application of voltage but the piezoelectric element 2 does not elongate because no voltage is applied thereon. Consequently, an angular displacement takes place between the surface 1a of the displacement part 1 and the surface 5a of the fixed part 5. Since stiffness at the displacement regulating section 4 is set in such a way that an angular displacement takes place between the surfaces 1a, 5a with hinges 6a, 6b secured to the piezoelectric element 2 as fulcrums, tensile force is not applied on the piezoelectric element 2 which is thereby protected against breakdown.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a displacement magnifying mechanism for a structure that requires a minute angle control between mutual surfaces of a fixed portion and a displaced portion, and more particularly to the fixed portion and the displaced portion due to expansion of a piezoelectric element. The present invention relates to a displacement magnifying mechanism that performs an angular displacement with respect to a portion.

[0002]

2. Description of the Related Art A conventional displacement magnifying mechanism will be described with reference to the front view of FIG.
b is a rod-shaped piezoelectric element 2 having hinges 6a and 6b fixed at both ends between one surface 5b of the fixed portion 5 facing the displacement portion 1, and a piezoelectric element 3 having hinges 7a and 7b fixed at both ends. Is fixed to the one surface 5b of the fixing portion 5. In this configuration, the surface 1a of the displacement portion 1 has the piezoelectric elements 2 and 3 to which the voltages controlled separately are applied.
It is pushed up from the fixed portion 1 by each extension, and the surface 1a of the fixed portion 5 is caused by the difference in extension length of the piezoelectric elements 2 and 3.
The angle formed by and is controlled in two directions. The hinge 6a,
6b, 7a and 7b generally have a smaller thickness than the piezoelectric elements 2 and 3 so as to have flexibility, so that the angular displacement between the surface 5a of the fixed portion 5 and the surface 1a of the displacement portion 1 is reduced. It is easy to occur. Also, the hinges 6a, 6b, 7a
When the same material as that of the fixed portion 5 and the displacement portion 1 is used for 7 and 7b, for example, metal or the like, they may be integrally formed with the fixed portion 5 and the displacement portion 1, respectively. Furthermore, the piezoelectric element 2
And 3 may be stacked.

[0003]

In this conventional displacement magnifying mechanism, when the piezoelectric element is energized to generate an angular displacement between the surfaces of the fixed part and the displacing part, the one having a small degree of extension of the applied electric power. When a tensile force is applied to the piezoelectric element, the piezoelectric element that is pulled may be damaged.

[0004]

DISCLOSURE OF THE INVENTION A displacement magnifying mechanism of the present invention comprises a fixed portion, a displaced portion facing the fixed portion, and one surface of the fixed portion and one surface of the displaced portion fixed by hinges at both ends. And two piezoelectric elements that expand by applying electric power, and by applying electric power to one or both of the piezoelectric elements, the angular displacement between the surfaces of the fixed portion and the displaced portion in two directions. In the displacement magnifying mechanism to be controlled, the displacement magnifying mechanism is further arranged between the two piezoelectric elements to fix the one surface of the fixed portion and the one surface of the displaced portion by the hinge portions at both ends, and the piezoelectric element. A displacement adjusting portion having rigidity to cause the angular displacement with the other hinge of the piezoelectric element as a fulcrum when one of the elements is energized is provided.

[0005]

The present invention will be described below with reference to the drawings.

FIG. 1 is a side view of an embodiment of the present invention.
The displacement magnifying mechanism of FIG. 1 has, in addition to the displacement magnifying mechanism of the prior art shown in FIG. 3, hinge portions 4a and 4b at both ends between the piezoelectric elements 2 and 3 and the hinge portions 4a and 4b. Thus, a rod-shaped displacement adjusting portion 4 fixed to the surface 1a of the displacement portion 1 and the surface 5a of the fixed portion 5 is provided. The displacement adjusting section 4 is made of Invar or the like, and when one piezoelectric element, for example, the piezoelectric element 3 is energized to expand the piezoelectric element 3, the hinge 7a fixed to the other piezoelectric element 2 is used. And 7b have a rigidity value for angularly displacing the displacement portion 1 with the fulcrum as a fulcrum. This rigidity value can be selected by changing the thickness of the displacement adjusting section 4, for example.

Next, the operation of the displacement magnifying mechanism will be described with reference to the front view of the embodiment of FIG. 1 in operation shown in FIG. When a voltage is applied to the piezoelectric element 3, this element 3 expands. On the other hand, no voltage is applied to the piezoelectric element 2 and this element 2 does not expand. Therefore, the surface 1a of the displacement portion 1
When the displacement portion 1 is pushed up by the piezoelectric element 3, an angular displacement is generated between the displacement portion 1 and the surface 5a of the fixed portion 5. Here, the rigidity of the displacement adjusting portion 4 is a value such that angular displacement occurs between the surfaces 1a and 5a of the displacement portion 1 and the fixed portion 5 with the hinges 6a and 6b fixed to the piezoelectric element 2 as fulcrums. Therefore, no tensile force is generated in the piezoelectric element 2. In addition, in order to generate the angular displacement in the opposite direction to the above, as an example, it suffices to apply electricity only to the piezoelectric element 2.

[0008]

As described above, according to the present invention, two-direction angular displacement is generated between the surface of the displacement portion and the surface of the fixed portion.
When a displacement adjusting section is further provided between two piezoelectric elements and only one piezoelectric element is energized, the displacement adjusting section of the displacement adjusting section is arranged so that the hinges at both ends of the other piezoelectric element serve as fulcrums to cause an angular displacement in the displaced section. Since the rigidity is set, there is an effect that it is possible to prevent a tensile force from being applied to the other piezoelectric element to damage the other piezoelectric element.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is a front view of the embodiment of FIG. 1 in operation.

FIG. 3 is a front view of a conventional displacement magnifying mechanism.

[Explanation of symbols]

 1 Displacement part 1a, 1b Displacement part surface 2,3 Piezoelectric element 4 Displacement adjusting part 4a, 4b Hinge part 5 Fixed part 5a, 5b Fixed part surface 6a, 6b, 7a, 7b Hinge

Claims (1)

[Claims] 1. A fixed part, a displacement part facing the fixed part, and two piezoelectric elements that fix one surface of the fixed part and one surface of the displaced part with hinges at both ends and expand by applying electricity. In the displacement enlarging mechanism for controlling the angular displacement between the surfaces of the fixed portion and the displacing portion in two directions by applying electric power to one or both of the piezoelectric elements, Further, the piezoelectric element is arranged between the two piezoelectric elements to fix one surface of the fixed portion and one surface of the displacement portion by hinge portions at both ends, and the piezoelectric element when one of the piezoelectric elements is energized. A displacement magnifying mechanism comprising a displacement adjusting portion having rigidity to cause the above-mentioned angular displacement with the other hinge as a fulcrum.