JPH071448B2 - Fine positioning device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fine positioning apparatus used for a semiconductor manufacturing apparatus, an electron microscope, or any other apparatus that requires adjustment on the order of sub-μm.

[Conventional technology]

In recent years, in various technical fields, a device capable of fine displacement adjustment on the order of sub-μm has been demanded. A typical example thereof is a semiconductor manufacturing apparatus such as an LSI (Large Scale Integrated Circuit), a mask aligner used in a manufacturing process of a VLSI, an electron beam drawing apparatus and the like. In these devices,
Submicron-order fine positioning is required, and as the positioning accuracy improves, the degree of integration increases, and high-performance products can be manufactured. Such fine positioning is necessary not only in the above-mentioned semiconductor device but also in various high-magnification optical devices such as electron microscopes, and by improving its precision, even in advanced technologies such as biotechnology and space development. Will greatly contribute to the development of.

Conventionally, such a fine positioning device is disclosed, for example, in "Mechanical Design" magazine, Vol. 27, No. 1 (January 1983), pages 32 to 32.
Various types have been proposed, as shown on page 36. Among these, since it is considered that a fine positioning device of a mold using a parallel spring and a fine movement actuator is superior in that a particularly complicated displacement reduction mechanism is unnecessary and the configuration is simple, Will be described with reference to FIG.

FIG. 4 is a side view of a conventional fine positioning device. In the figure, 1 is a support, 2a and 2b are plate-shaped parallel springs fixed in parallel to each other on the support 1, and 3 is a highly rigid fine movement table fixed on the parallel springs 2a and 2b. Reference numeral 4 denotes a fine movement actuator mounted between the support base 1 and the fine movement table 3. A piezoelectric element, an electromagnetic solenoid, or the like is used for the fine movement actuator 4, and when it is excited, a force in the x-axis direction of the coordinate axis shown in the drawing is applied to the fine movement table 3.

Here, due to the structure of the parallel springs 2a and 2b, the rigidity in the x-axis direction is low, whereas the rigidity in the z-axis direction, the y-axis direction, and the direction (perpendicular to the paper surface) are high, so that the fine motion actuator is excited. Then, the fine movement table 3 is displaced only in the x-axis direction, and the displacement in the other direction hardly occurs.

FIG. 5 is a perspective view of another conventional micro-positioning device easily conceivable from the examples disclosed in the aforementioned references. In the figure, 6 is a support base, 7a and 7b are plate-shaped parallel springs fixed to each other on the support base 6, 8 is an intermediate table having high rigidity fixed to the parallel springs 7a and 7b, and 9a and 9b are parallel springs. A plate-shaped parallel spring fixed to the intermediate table 8 in parallel with each other in a direction orthogonal to 7a and 7b, and a high-rigidity fine movement table fixed to the parallel springs 9a and 9b. When the coordinate axes are determined as shown in the figure, the parallel springs 7a and 7b are arranged along the x-axis direction, and the parallel springs 9a and 9b are arranged along the y-axis direction. This structure is basically a structure in which the structure for one axis (which causes displacement in the x-axis direction) shown in FIG. 4 is laminated in two stages. An arrow Fx indicates a force in the x-axis direction applied to the fine motion table 10, and an arrow Fy indicates a force in the y-axis direction applied to the intermediate table 8, which is supported by a fine motion actuator (not shown) capable of applying the forces Fx and Fy. Stand 6 and fine table 1
0, provided between the support base 6 and the intermediate table 8, respectively.

When a force Fx is applied to the fine motion table 10, the parallel springs 9a, 9b
However, since the parallel springs 7a and 7b have high rigidity with respect to the force Fx in the x-axis direction, the fine motion table 10 is almost x.
Displaces only in the axial direction. When a force Fy is applied to the intermediate table 8, the parallel springs 7a and 7b are deformed and the fine movement table 1
0 is displaced substantially only in the y-axis direction via the parallel springs 9a and 9b. Further, when both forces Fx and Fy are applied at the same time, the parallel springs 7a, 7b, 9a and 9b are simultaneously deformed, and the fine movement table 10 is moved.
Is two-dimensionally displaced according to these.

As described above, the apparatus shown in FIG. 5 can perform positioning in the biaxial directions, whereas the apparatus shown in FIG. 4 is a positioning apparatus in the uniaxial directions only. The apparatus shown in FIGS. 4 and 5 described above is an apparatus for linearly displacing the fine movement table 10 in a predetermined axial direction. On the contrary,
A fine positioning device for finely rotating a fine movement table around a certain axis is disclosed in Japanese Patent Application Publication No. 57-50433.
No. This fine positioning device will be described with reference to FIG.

FIG. 6 is a partially cutaway perspective view of a conventional fine positioning device which performs fine rotational displacement. In the figure, 11 is a cylindrical central fixing portion, and 11a, 11b, 11c are vertical grooves formed on the circumferential surface of the central fixing portion 11 at equal intervals in the longitudinal direction. Reference numeral 12 denotes a ring-shaped stage that is rotatably provided around the central fixed portion 11.
a _{1 to} 12a ₃ , 12b _{1 to} 12b ₃ , 12c _{1 to} 12c ₃ are vertical grooves 11a, 11 respectively.
The U-shaped metal fitting is fixed to the stage 12 so as to face b and 11c. 13 is each vertical groove 11a, 11b, 11c and each U-shaped metal fitting 12a _{1 to} 12c
A bimorph type piezoelectric element 13A mounted between the two and ₃ is a projection fixed to a portion of the bimorph type piezoelectric element 13 that engages with the U-shaped metal fitting. The central fixed portion 11, the stage 12, the U-shaped bracket 12a ₁ ~12c ₃ is rigid both. Here, the bimorph type piezoelectric element 13 will be briefly described with reference to FIG.

FIG. 7 is a perspective view of a bimorph type piezoelectric element. In the figure,
Reference numerals 13a and 13b are piezoelectric elements, and 13c is a common electrode provided between the piezoelectric elements 13a and 13b. The piezoelectric elements 13a and 13b are the common electrode 1
They are closely attached to each other with 3c clinging together. Reference numerals 13d and 13e denote surface electrodes fixed to the piezoelectric elements 13a and 13b, respectively. In this state, a voltage with a polarity that contracts the piezoelectric element 13a is applied between the surface electrode 13d and the common electrode 13c, and at the same time, a voltage with a polarity that extends the piezoelectric element 13d between the surface electrode 13e and the common electrode 13c is applied. When applied, each piezoelectric element 13a, 13b expands and contracts in the direction of the arrow, so that the entire bimorph piezoelectric element 13 is deformed as shown in the figure. With such a bimorph piezoelectric element 13, it is possible to obtain a large displacement amount as compared with a single piezoelectric element.

Such a bimorph type piezoelectric element 13 has a structure shown in FIG. 6 in which one end is fixed to the vertical grooves 11a, 11b, 11c and the other end is a free end, and the projection 13A is provided on each corresponding U-shaped metal fitting. Are in contact through. Now, when an appropriate voltage is applied to each bimorph piezoelectric element 13 to cause the deformation shown in FIG. 7,
The stage 12 is rotationally displaced about the central fixed portion 11 according to the deformation. Therefore, if the fine movement table is placed and fixed on the stage 12, a fine rotational displacement of the fine movement table can be obtained.

The above-mentioned conventional device includes a U-shaped metal fitting and a bimorph piezoelectric element.
13 and both are held in an engaged state, which allows the bimorph type piezoelectric element 13 to be mounted while being naturally deformed,
In addition, displacement constraint (interference) that occurs when the bimorph piezoelectric element 13 is fixed to the stage 12 is prevented.

[Problems to be Solved by the Invention]

By the way, the fine positioning device shown in FIGS. 4 and 5 can only perform one-dimensional and two-dimensional positioning, and can provide displacement in the z-axis direction and rotational displacement about the x-axis, y-axis, and z-axis. In addition, the fine positioning device shown in FIG. 6 cannot give displacements in the x-axis, y-axis, and z-axis directions and rotational displacements around the other two axes. Further, from these conventional fine positioning devices, a three-axis fine positioning device is assumed which combines the devices shown in FIGS. 5 and 6 to provide displacement in the x-axis and y-axis directions and rotational displacement around the z-axis. However, it is extremely difficult to construct a fine positioning device with four or more axes from them.

The present invention has been made in view of the above circumstances, and an object thereof is to solve the above-mentioned problems of the prior art, and to displace in the x-axis, y-axis, z-axis direction, and x-axis with a simple structure. Another object of the present invention is to provide a fine positioning device capable of giving rotational displacement about the y-axis and the z-axis.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention is directed to project symmetrically from a first central rigid body portion in a first axial direction and to each projecting portion at right angles to the first axial direction. A second set of overhanging portions, each of which has a parallel flexural beam displacement mechanism for generating a translational displacement in the second axial direction, and has an end of each protruding portion connected to a fixed portion,
And a second set of overhangs provided with parallel flexural beam displacement mechanisms that cause translational displacement in the first axial direction at each projecting portion that symmetrically projects in the second axial direction from the first central rigid body portion. A first block having a portion and a second central rigid body portion that symmetrically protrudes in the second axial direction, and a third block that is orthogonal to the first axial direction and the second axial direction in each protruding portion. A second block including a parallel flexural beam displacement mechanism for generating a translational displacement in the axial direction, and an end of each of the protrusions in the second axial direction connected to an end of each of the overhanging portions of the second set; A first radial flexural beam displacement mechanism set on a rigid ring for generating rotational displacement about the first axis and a second set for generating rotational displacement about the second axis.
Of radial flexure beam displacement mechanisms, as well as symmetrically projecting from a third central rigid body portion connected to the second central rigid body portion through a space surrounded by the ring, and the third axis at each projecting portion. A third radial flexible beam displacement mechanism for generating a rotational displacement around is provided, and end portions of the respective projecting portions projecting from the third central rigid body portion and respective rigid body portions of one set of the radial flexible beam displacement mechanism. And a fine movement table connected to each rigid body portion of the radial bending beam displacement mechanism to which the third radial bending beam displacement mechanism of the third block is not connected. It is characterized in that a positioning device is configured.

[Action]

Three parallel flexible beam displacement mechanisms cause translational displacements in the x-axis, y-axis, and z-axis directions, and three radial flexible beam displacement mechanisms cause rotational displacements around the x-axis, y-axis, and z-axis. Cause

〔Example〕

 Hereinafter, the present invention will be described based on the illustrated embodiments.

FIG. 1 is an exploded perspective view of a fine positioning device according to an embodiment of the present invention. In the figure, x, y, and z indicate coordinate axes that are orthogonal to each other. 15 is a central rigid body made of a highly rigid member, 16a is an overhanging portion that extends from the central rigid body portion 15 in the y-axis direction, 16b is an overhanging portion that extends from the central rigid body portion 15 in the opposite direction to the overhanging portion 16a, and 17a is the center. Reference numeral 17b denotes a projecting portion projecting from the rigid body portion 15 in the x-axis direction, and reference numeral 17b denotes a projecting portion projecting from the central rigid body portion 15 in the opposite direction to the projecting portion 17a. Reference numerals 18a and 18b denote fixing portions provided at lower ends of the protruding portions 16a and 16b, and 19a and 19b denote connecting portions provided at upper end portions of the protruding portions 17a and 17b, respectively. The overhanging portions 16a, 16b, 17a, 17b, the fixing portions 18a, 18b, and the connecting portions 19a, 19b are each made of the same member as the central rigid body portion 15, and are integrally machined together with the central rigid body portion 15.

16Fxa and 16Fxb are parallel flexural beam displacement mechanisms formed in the overhanging portions 16a and 16b, respectively, and are symmetrically configured with respect to the central rigid body portion 15. Parallel flexible beam displacement mechanism 16Fx
a, 16Fxb cooperate to generate translational displacement in the x-axis direction. S
Indicates a strain gauge provided on the parallel flexural beam displacement mechanism 16Fxa, 16Fxb (the strain gauge is indicated by symbol S in each displacement mechanism below). Reference numerals 17Fya and 17Fyb are parallel bending beam displacement mechanisms formed in the overhanging portions 17a and 17b, respectively, and are symmetrically configured with respect to the central rigid body portion 15. The parallel flexible beam displacement mechanisms 17Fya and 17Fyb cooperate to generate a translational displacement in the y-axis direction. Parallel flexible beam displacement mechanism 16Fx
The a, 16Fxb, 17Fya and 17Fyb are formed by forming a predetermined through hole at a predetermined position of each overhanging portion 16a, 16b, 17a, 17b. The structure of the parallel flexible beam displacement mechanism will be described later. The block B ₁ is configured by the above-mentioned parts and the parallel flexible beam displacement mechanism.

Next, the configuration of the block B ₂ will be described. Reference numeral 21 is a central rigid portion made of a member having high rigidity, 22a is a projecting portion that projects from the central rigid body portion 21 in the x-axis direction, and 22b is a projecting portion that projects from the central rigid body portion 21 in the opposite direction to the projecting portion 22a. 23a, 23b is a linking protruding respectively overhang 22a, from the end lower 22b, connecting portions 19a of the block B _1, is coupled with 19b.
This bond is indicated by a chain double-dashed line. The central rigid body portion 21, the respective overhang portions 22a and 22b, and the connecting portions 23a and 23b are integrally machined from one member. 22Fza and 22Fzb are parallel flexural beam displacement mechanisms formed on the overhanging portions 22a and 22b, respectively, and are symmetrically arranged with respect to the central rigid body portion 21. These parallel flexible beam displacement mechanisms 22Fza and 22Fzb cooperate to generate translational displacement in the z-axis direction. The parallel flexural beam displacement mechanism 22Fza, 22Fzb is formed by forming a predetermined through hole at a predetermined position of each overhanging portion 22a, 22b.

Next, the configuration of the block B ₃ will be described. The block B ₁ is configured to perform translational displacement in the x-axis direction and the y-axis direction, and the block B ₂ is configured to perform translational displacement in the z-axis direction.
B ₃ is configured to perform rotational displacement around the x axis, the y axis, and the z axis. That is, 24 is a rectangular ring made of a rigid member. 25Mya and 25Myb are radial deflection beam displacement mechanisms symmetrically arranged on the ring 24. Each radial flexure beam displacement mechanism 25Mya, 25Myb causes a rotational displacement about a common axis extending in the y-axis direction. 25Mxa and 25Mxb are ring 2
Radial flexural beam displacement mechanisms symmetrically arranged on 4 and each of them generate a rotational displacement about a common axis extending in the x-axis direction. Radiant flexible beam displacement mechanism 25
The structures of Mya, 25Myb, 25Mxa and 25Mxb will be described later.

26a and 26b are one rigid body part (the other rigid body part is a ring 24), which constitutes the radial bending beam displacement mechanism 25Mya and 25Myb, 27
a and 27b are one rigid body part that constitutes the flexural beam displacement mechanism 25Mxa and 25Mxb, respectively (the other rigid body part is also the ring 24)
Is. 27a 'and 27b' are connecting portions provided on the rigid body portions 27a and 27b, respectively.

Reference numeral 28 is a central rigid body portion, 29a is a projecting portion that projects from the central rigid body portion 28 in the y-axis direction, and 29b is a projecting portion that projects from the central rigid body portion 28 in the opposite direction to the projecting portion 29a. Overhang 29a, rigid flexure beam displacement mechanism 25Mya rigid body 26a, and overhang
29b and the rigid body portion 26b of the radial flexible beam displacement mechanism 25Myb are connected to each other.

29Mza and 29Mzb are radial bending beam displacement mechanisms formed on the overhanging portions 29a and 29b, respectively, and are symmetrically arranged with respect to the central rigid body portion 28. These parallel flexural beam displacement mechanisms 29Mza and 29Mzb work together to generate rotational displacement about the z-axis. These radial flexible beam displacement mechanisms 29Mza, 29Mzb and the radial flexible beam displacement mechanisms 25Mxa, 25Mxb, 25Mya, 25Myb
Are each formed by forming a predetermined through hole at a predetermined position. The structure of the radial flexible beam displacement mechanism will be described later.

The ring 24, the rigid body portions 26a, 26b, 27a, 27b, the radial bending beam displacement mechanisms formed between them, the central rigid body portion 28, and the overhang portions 29a, 29b are integrally formed by a member having high rigidity. .

Such a block B ₃ is joined to the block B ₂ by its central rigid part 28. That is, the central rigid body portion 28 of the block B ₃
Are laid on the central rigid body portion 21 of the block B ₂ and connected by an appropriate means (one of these connections is shown by a chain double-dashed line in the figure). In this state, a large part of block B ₂ is blocked by block B ₃
Will enter the space. Then, the radial flexible beam displacement mechanism 25Mxa, 25Mxb, 25Mya, 25Myb is suspended from the overhanging portions 29a, 29b together with the ring 24.

30 is a fine-adjustment table, overhang the block B ₃
Rigid body on the side where 29a and 29b are not connected, that is, rigid body 2
7a and 27b are connected to the connecting portions 27a 'and 27b' (one of these connections is shown by a chain double-dashed line in the figure). The shape of the fine movement table 30 is not limited to the rectangular shape shown in the figure,
For example, a substantially square shape having a larger dimension in the y-axis direction can be used to easily mount and fix a symmetrical object.

In this state, each radiating flexible beam displacement mechanism 25Mxa, 25Mx
By selecting the radiation angles of the bending beams (described later) of b, 25Mya, 25Myb, 29Mza, and 29Mzb, their respective rotation axes can be made orthogonal at one point on the surface of the fine movement table 26.

Here, the structures of the parallel flexible beam displacement mechanism and the radial flexible beam displacement mechanism in the above structure will be described with reference to the drawings. Second
(A), (b) is a side view of a symmetric parallel bending beam displacement mechanism.

In the figure, 31a, 31b and 31c are rigid body parts, and 34a ₁ and 34a ₂ are rigid body parts 31c and 31c.
It is a parallel flexible beam connected in parallel to each other between a. The parallel flexible beams 34a ₁ and 34a ₂ are formed by through holes 32a formed in the rigid body portion. 34b ₁ and 34b ₂ are parallel flexible beams connected in parallel to each other between the rigid body portions 31c and 31b, and are formed by through holes 32b formed in the rigid body portions. Reference numerals 36a and 36b denote piezoelectric actuators, which are mounted between the projecting portions from the rigid body projecting into the through holes 32a and 32b, respectively. With the configuration on the left side from the center of the rigid body portion 31c, the parallel flexible beam displacement mechanism 39a is
Further, the parallel flexible beam displacement mechanism 39b is configured by the configuration on the right side. S is a strain gauge attached to the parallel flexible beam at a proper position, and is provided to detect the deformation amount of the parallel flexible beam.

Here, the coordinate axes are defined as shown (the y axis is the direction perpendicular to the paper surface). Now, a voltage is applied to the piezoelectric actuators 36a and 36b at the same time to generate a force f in the Z-axis direction of the same magnitude. At this time, the displacement occurring in one of the parallel flexible beam displacement mechanisms, for example, the parallel flexible beam displacement mechanism 39a will be considered.
By applying a voltage to the piezoelectric actuator 36a, the rigid portion 31c is pressed in the z-axis direction by the force f. Therefore, the parallel flexible beams 34a ₁ and 34a ₂ undergo bending deformation similarly to the parallel springs 2a and 2b shown in FIG. 4, and the rigid body portion 31c is displaced in the z-axis direction as shown in FIG. 2 (b). To do. At this time, if the other parallel flexural beam displacement mechanism 39b does not exist, lateral displacement (displacement in the x-axis direction) should occur at the same time in the rigid portion 31c, although it is extremely small.

Further, when the parallel flexural beam displacement mechanism 39a does not exist, considering the displacement generated in the other parallel flexural beam displacement mechanism 39b, the parallel flexural beam displacement mechanism 39b is a surface along the y-axis direction passing through the center of the rigid portion 31c (reference Since it is configured to be plane-symmetric with the flexural beam displacement mechanism 39a parallel to the plane), when a force f that is plane-symmetric with respect to the reference plane is received, the rigid body portion is similar to the above.
The lateral displacement occurs in the 31c at the same time as the displacement in the z-axis direction, and its magnitude and direction are plane-symmetric with that of the parallel flexible beam displacement mechanism 39a with respect to the reference plane. That is, regarding the lateral displacement, the lateral displacement generated in the parallel flexible beam displacement mechanism 39b is leftward in the figure for displacement in the x-axis direction, and counterclockwise in the figure for rotational displacement around the y-axis.
The lateral displacement occurring in the parallel flexural beam displacement mechanism 39a occurs rightward in the figure for displacement in the x-axis direction, and occurs clockwise in the diagram for rotational displacement around the y-axis. The magnitude of each x-axis direction displacement and the magnitude of rotational displacement about the y-axis are equal. Therefore, the lateral displacements that occur on both sides cancel each other. As a result, the force f is applied,
Rigid body portion 31c produces a displacement (main displacement) ε only in the z-axis direction due to a slight increase in internal stress due to the extension in the longitudinal direction of each of the parallel flexible beams 34a ₁ , 34a ₂ , 34b ₁ , 34b _2. .

When the voltage applied to the piezoelectric actuators 36a, 36b is removed, each of the parallel flexible beams 34a ₁ , 34a ₂ , 34b ₁ , 34b ₂ returns to the state before deformation, and the parallel flexible beam displacement mechanisms 39a, 39b move to the first position. Returning to the state shown in FIG. 2 (a), the displacement ε becomes zero. In the above operation, if the feed back control is performed using the actual displacement amount detected by the strain gauge S, accurate fine positioning can be performed.

3 (a) and 3 (b) are side views of the radial flexible beam displacement mechanism. In the figure, 41a, 41b, 41c are rigid parts, 44a ₁ , 44a ₂ , 44b ₁ ,
44b ₂ is a radiating flexible beam. Radiant flexible beams 44a ₁ , 44
a ₂ , 44b ₁ and 44b ₂ extend radially along the alternate long and short dash lines L ₁ and L ₂ with respect to an axis O that is perpendicular to the plane of the paper passing through the center of the rigid body portion 41c and connects adjacent rigid body portions. ing. The radial flexible beams 44a ₁ and 44a ₂ are formed by forming the through holes 42a, and the radial flexible beams 44b ₁ and 44b ₂ are formed by forming the through holes 42b. Reference numerals 46a and 46b denote piezoelectric actuators, which are mounted in the through holes 42a and 42b between the protruding portions protruding from the rigid body portion. The configuration on the left side of the axis O constitutes the radial bending beam displacement mechanism 49a, and the configuration on the right side constitutes the radial bending beam displacement mechanism 49b. S is a strain gauge attached to an appropriate position of the radiating flexible beam, and is provided to detect the amount of deformation of the radiating flexible beam.

Now, a predetermined voltage is applied to the piezoelectric actuators 46a and 46b at the same time to generate a force f of the same magnitude in a tangential direction to a circle centered on the central axis O. Then, the rigid body part
The left protrusion of 41c is pushed upward along the tangent line by the force generated in the piezoelectric actuator 46a, and the rigid body 41c
The right-hand protruding portion is pushed downward along the tangent line by the force generated in the piezoelectric actuator 46b. Rigid part 41c
Is a flexible beam radiated to both rigid body parts 41a and 41b 44a ₁ , 44a ₂ , 44b ₁ , 44b ₂
As a result of receiving the above-mentioned force, as shown in FIG. 3 (b), the radiating flexible beams 44a ₁ , 44a ₂ ,
The portion connected to the rigid body portions 41a and 41b of 44b ₁ and 44b ₂ is point O.
The straight lines L ₁ and L ₂ extending radially from the straight line L ₁ and L ₂ are connected to the rigid body portion 41c, and the straight lines are slightly deviated from the straight lines L ₁ and L ₂ (the straight lines also extend radially from the point O). A slight displacement that shifts on L ₁ ′ and L ₂ ′ is generated. Therefore, the rigid body portion 41c rotates clockwise by a minute angle δ in the figure. The magnitude of this rotational displacement δ is determined by the radial flexible beams 44a ₁ and 44a.
Since it is determined by the rigidity of ₂ , 44b ₁ and 44b ₂ against bending, if the force f is accurately controlled, the rotational displacement δ can be controlled with the same accuracy.

When the voltage applied to the piezoelectric actuators 46a, 46b is removed, the radiating flexible beams 44a ₁ , 44a ₂ , 44b ₁ , 44b ₂ return to the state before deformation, and the rotary displacement mechanism is shown in FIG. 3 (a). Returning to the state shown, the displacement δ becomes zero. In the above-described operation, the strain gauge S is used for performing accurate fine positioning as in the case of the parallel flexible beam displacement mechanism.

In addition, the radial flexible beam displacement mechanism 25Mxa, 25Mxb, shown in FIG.
Obviously, 25Mya and 25Myb correspond to one of the radial bending beam displacement mechanisms 49a (49b) shown in FIG. 3 (a), and the operation thereof also conforms to the above operation.

Next, the operation of this embodiment shown in FIG. 1 will be described. Now, when a voltage is applied to each piezoelectric actuator of the parallel flexible beam displacement mechanism 16Fxa, 16Fxb, the parallel flexible beam 34a ₁ , 34a ₂ , 34
b ₁ and 34b ₂ are deformed in the x-axis direction in FIG. 1 as shown in FIG. 2 (b) according to the applied voltage, and are displaced in translation. This translational displacement is caused by the central rigid body portion 15, the parallel flexible beam displacement mechanism 17Fya, 17Fyb,
22Fza, 22Fzb, central rigid body parts 21, 28, radial flexure beam displacement mechanism
29Mza, 29Mzb, rigid body parts 26a, 26b, radial flexible beam displacement mechanism 25
Mya, 25Myb, Ring 24, Radial flexible beam displacement mechanism 25Mxa, 25M
It is transmitted via xb to the fine movement table 30 fixed to the rigid body portions 27a, 27b, and the fine movement table 30 is translationally displaced in the x-axis direction by the same amount.

Similarly, when a voltage is applied to each of the piezoelectric actuators of the parallel flexible beam displacement mechanisms 17Fya and 17Fyb, the fine motion table 30 is translationally displaced in the y-axis direction, and the parallel flexible beam displacement mechanism 22
When a voltage is applied to each of the Fza and 22Fzb piezoelectric actuators, the fine movement table 30 is translationally displaced in the z-axis direction.

On the other hand, when a voltage is applied to each piezoelectric actuator of the radiating flexible beam displacement mechanism 25Mya, 25Myb, the radiating flexible beam is deformed as shown in FIG. 3 (b) according to this voltage. In this case, since the rigid body portions 26a and 26b are in a fixed state via the central rigid body portion 28 and the radial flexible beam displacement mechanisms 29Mza and 29Mzb, the radial flexible beam displacement mechanisms 25Mya and 25Myb perform rotational displacement about the y-axis. Occurs and this causes the fine movement table 30
Is rotationally displaced around the axis through the ring 24 and the radial flexure beam displacement mechanism 25Mxa, 25Mxb.

When a voltage is applied to each of the piezoelectric actuators of the radial flexure beam displacement mechanism 25Mxa, 25Mxb, the radial flexure beam is deformed according to this voltage, and rotational displacement is generated around the axis in the x-axis direction. This rotational displacement is transmitted to the fine movement table 30 via the rigid bodies 27a and 27b, and the fine movement table 30 is rotationally displaced about the axis.

Furthermore, when a voltage is applied to each piezoelectric actuator of the radiating flexible beam displacement mechanism 29Mza, 29Mzb, the radiating flexible beam 44
a ₁ , 44a ₂ , 44b ₁ and 44b ₂ are deformed and rotationally displaced around the axis in the z-axis direction in FIG. 1 as shown in FIG. 3B in accordance with the applied voltage. This rotational displacement is transmitted through the rigid body portions 26a, 26b, the parallel flexible beam displacement mechanism 25Mya, 25Fyb, the ring 24, the radial flexible beam displacement mechanism 25Mxa, 25Mxb, the rigid body portions 27a, 27b, and the fine movement table 30.
Then, the fine motion table 30 is rotationally displaced about the axis.

Although the above description is for translational displacement and rotational displacement about one axis, an arbitrary voltage is applied by selecting an arbitrary plurality of the parallel flexural beam displacement mechanism and the radial flexural beam displacement mechanism. As a result, the fine movement table 26 can be displaced arbitrarily. Further, the strain gauge S can be used to accurately control the displacement amount.

As described above, in the present embodiment, the parallel flexural beam displacement mechanism that performs translational displacement in the x-axis direction and the y-axis direction is configured in the first block, and the second block connected to the first block is in the z-axis direction. A parallel flexural beam displacement mechanism for translational displacement to the third block connected to the second block, x
A radial flexure beam displacement mechanism that rotationally displaces each of the axes, y-axis, and z-axis is configured, and the fine movement table is fixed to the third block, so it is extremely simple and compact, and easy to mount on the target device. It is possible to obtain a translational displacement of three axes and a rotational displacement of three axes which are easy to use. Further, since the respective rotation axes are orthogonal to each other at one point on the surface of the fine movement table, the rotation center of the rotational displacement exists on the fine movement table, and accurate rotational displacement can be performed.

In addition, in the description of the above embodiment, an example in which the end portion of the overhang portion in the y-axis direction is fixed in the block B ₁ and the connecting portion is provided at the end portion of the overhang portion in the x-axis direction has been described. On the contrary, it is obvious that the end of the overhang portion in the x-axis direction may be fixed and the block B ₂ may be connected to the end of the overhang portion in the y-axis direction. Further, each rotary shaft does not necessarily have to be present on the surface of the fine movement table, and can be arbitrarily selected.

〔The invention's effect〕

As described above, in the present invention, the first block is provided with the parallel flexural beam displacement mechanism that is displaced in translation in the x-axis direction and the y-axis direction, and the second block connected to the first block is provided with the z-axis. To the third block connected to the second block, which constitutes a parallel flexural beam displacement mechanism for translational displacement in the direction
A radial flexure beam displacement mechanism that rotationally displaces around the x-axis, y-axis, and z-axis is configured, and a fine movement table is connected to the third block, so it is extremely simple and compact, and can be mounted on the target device. It is possible to obtain triaxial translational displacement and triaxial rotational displacement that are easy and convenient to use.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a fine positioning apparatus according to an embodiment of the present invention, FIGS. 2 (a) and 2 (b) are side views of the radial bending beam displacement mechanism shown in FIG. 1, and FIG. 3 (a). , (B) are side views of the radial bending beam displacement mechanism shown in FIG. 1, FIGS. 4, 5 and 6 are side views and perspective views of a conventional fine positioning device, and FIG. 7 is FIG. 3 is a perspective view of a bimorph piezoelectric element used in the device shown in FIG. 15,21,28 …… Central rigid body part, 16a, 16b, 17a, 17b, 22a, 22b, 29
a, 29b …… Overhang part, 16Fxa, 16Fxb, 16Fya, 16Fyb, 22Fza, 2
2Fzb …… Parallel flexible beam displacement mechanism, 24 …… Ring, 25Mxa,
25Mxb, 25Mya, 25Myb, 29Mza, 29Mzb …… Radial flexural beam displacement mechanism, 30 …… Fine table, B ₁ , B ₂ , B ₃ … Block.

Front page continued (72) Inventor Ken Murayama 650 Jinrachi-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Tsuchiura factory (72) Inventor Hoshino ▲ Yoshi ▼ 650 Kintate-cho, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Ceremony Company Tsuchiura Factory (56) Reference JP 61-209846 (JP, A) JP 61-243511 (JP, A) JP 62-187912 (JP, A) JP 60-25284 ( JP, A) US Patent 3786332 (US, A)

Claims (4)

[Claims] 1. A parallel flexural beam displacement that symmetrically projects from a first central rigid body portion in a first axial direction and causes translational displacement in each projecting portion in a second axial direction orthogonal to the first axial direction. A first set of overhanging parts that includes a mechanism and has ends of each of the projecting parts connected to a fixing part, and the projecting parts that symmetrically project from the first central rigid body part in the second axial direction. A first block having a second set of overhangs provided with a parallel flexural beam displacement mechanism for generating a translational displacement in a first axial direction, and a second central rigid body portion symmetrical in the second axial direction To the first axial direction and the second axial direction at each projecting portion.
Is provided with a parallel flexural beam displacement mechanism for generating a translational displacement in a third axial direction orthogonal to the axial direction of the second axial direction, and the ends of the respective projecting portions in the second axial direction are end portions of the respective projecting portions of the second set A second block coupled to the first block, a first radial flexural beam displacement mechanism set on the ring of the rigid body for generating rotational displacement about the first axis, and rotational displacement about the second axis. A second set of radial flexural beam displacement mechanisms to be generated, as well as symmetrically projecting from a third central rigid body part connected to the second central rigid body part through a space surrounded by the ring, and at each of the projecting parts. A third radial flexible beam displacement mechanism for generating rotational displacement about a third axis is provided, and one set of the end portion of each of the projecting portions projecting from the third central rigid body portion and the radial flexible beam displacement mechanism. Of the rigid body parts of And a fine movement table connected to each rigid body portion of the radial bending beam displacement mechanism to which the third radial bending beam displacement mechanism of the third block is not connected, Fine positioning device. 2. The parallel flexural beam displacement mechanism according to claim 1, wherein the parallel flexural beam displacement mechanism includes a plurality of flexural beams which are parallel to each other and which connect the central rigid body part and the corresponding overhanging part. A fine positioning device comprising: an actuator that causes a beam to be bent and deformed by the force in the axial direction. 3. The radiating flexible beam displacement mechanism according to claim 1, wherein the radial bending beam displacement mechanism is the first shaft or the second shaft.
A plurality of flexible beams extending radially with respect to the axis of
A fine positioning device comprising: an actuator that causes the bending beam to generate bending deformation due to a moment about the axis. 4. A fine positioning device according to claim 2 or 3, wherein the actuator is a piezoelectric actuator.