JPH01192182A - actuator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an actuator for a movement mechanism that requires fine positioning, such as a stage for a semiconductor exposure apparatus.

[Prior Art] FIG. 3 shows a fine positioning actuator used in a conventional semiconductor exposure apparatus or the like. This actuator is used by incorporating a displacement generation source such as an electrostrictive element into a lever expansion mechanism formed by cutting out a single plate. As shown in the figure, one end of the electrostrictive element 1 is fixedly supported by a fixed end member 2, and an operating member 4 is connected to the fixed end member 2 via an elastic hinge 3. The other end (movable end) of the strain element 1 is engaged.

[Problems to be Solved by the Invention] The conventional example described above has low rigidity because the fixed end of the electrostrictive element is a cantilever beam. In addition, there was a drawback that the mechanical part had to be large in order to obtain high rigidity. In general, the displacement generated by an electrostrictive element, etc., which is a displacement generation source is 1/1000 of the free length.
Therefore, when attaching both ends of the electrostrictive element, which is a source of displacement, there is a drawback that required displacement and rigidity cannot be obtained if there is a gap or a thick adhesive layer.

[Means and effects for solving the problems] The present invention includes the fixed end member of the electrostrictive element being integrated with the elastic hinge member that is the fulcrum of the expansion lever, and the electrostrictive element that is the displacement source. By enclosing it in a box shape, it has a structure that is highly rigid and can effectively expand the displacement of the displacement source.

[Example] An embodiment of the actuator according to the present invention is shown in FIG.

1 is an electrostrictive element that is a displacement generation source, 2 is a fixed end member, 3 is an elastic hinge that is a fulcrum of the lever, 4 is an arm that is an action part of the lever, and 5 is an equalizing element that prevents the generation of gaps due to rotation. Elastic hinge 6 is a base. The electrostrictive element 1 has one end (the end on the back side, not shown) fixed to the fixed end member 2. This fixed end member 2 is box-shaped and surrounds the electrostrictive element 1. The arm 4, which is an operating member, is formed integrally with the fixed end member 2 together with the elastic hinge 3. The front end of the electrostrictive element 1 engages with the arm 4 via an equalizing elastic hinge 5.

In the above configuration, when a voltage is applied to the electrostrictive element 1, the electrostrictive element 1 is displaced in its axial direction and applies force to the arm 4 via the equalizing elastic hinge 5, and the arm 4 rotates the fulcrum (elastic hinge) 3. The center is displaced in the normal direction of the base 6.

FIG. 2 shows another embodiment of the invention. In this embodiment, two electrostrictive elements 1a and lb are arranged in the expansion and contraction direction (axial direction).
are arranged in parallel so that they are parallel to each other, one end of each electrostrictive element 1a and lb is mechanically connected to each other via a coupling jig mechanism 7, and the end of one electrostrictive element 1a is a fixed end. It is fixed to the member 2, and the end of the other electrostrictive element engages with the arm 4 via the equalizing elastic hinge 5. Other structures and functions are the same as those of the embodiment shown in FIG.

In the above configuration, when a voltage is applied to the electrostrictive elements 1a and lb, the displacement of the electrostrictive element 1a is transmitted to the electrostrictive element 1b via the coupling mechanism 7, and is added to the displacement of the electrostrictive element 1b to form an equalizing elastic hinge. Force is applied to arm 4 via 5. The arm 4 is displaced in the normal direction of the base 6 with the fulcrum (elastic hinge) 3 as the center of rotation.

[Effects of the Invention] As explained above, in a displacement magnifying mechanism using a lever, the fixed end member is integrated with the hinge part that is the fulcrum of the lever and is formed into a box shape that surrounds the displacement source, thereby making it possible to generate the displacement source. It becomes possible to transmit the displacement to the point of action without waste. Furthermore, since the fixed end member is box-shaped to increase rigidity, the rigidity at the point of action is increased.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of one embodiment of an actuator according to the present invention, FIG. 2 is a perspective view of another embodiment of the present invention, and FIG. 3 is an explanatory diagram of a conventional actuator. 1: Electrostrictive element, 2: Fixed end member, 3: Elastic hinge (lever fulcrum), 4: Arm, 5: Elastic hinge for equalizing. Figure 1 Figure 2 Figure 3

Claims (6)

[Claims] (1) A displacement generating element that is displaced by expansion and contraction, a fixed end member that fixedly supports one end of the displacement generating element, and a movable end of the displacement generating element engage with each other, allowing the displacement generating element to be displaced with respect to the fixed end member. An actuator comprising: a member, wherein the acting member is integrally formed with the fixed end member via a fulcrum portion, and the fixed end member is configured in a box shape surrounding the displacement generating element. . (2) The actuator according to claim 1, wherein the fulcrum portion is constituted by an elastic hinge formed integrally with the fixed end member and the action member. (3) The actuator according to claim 1 or 2, characterized in that an equalizing mechanism for preventing generation of a gap is interposed between the movable end of the displacement generating element and the action member. (4) The actuator according to claim 1, 2, or 3, wherein the displacement generating element is an electrostrictive element that generates displacement by applying a voltage. (5) The actuator according to any one of claims 1 to 4, wherein the acting member is configured to apply a compressive force to the displacement generating element. (6) Two displacement generating elements are arranged in parallel so that their expansion and contraction directions are parallel to each other, one end of one displacement generating element is fixed to the fixed end member, and the other end is one end of the other displacement generating element. 6. The actuator according to any one of claims 1 to 5, wherein the other end of the other displacement generating element is engaged with the operating member.