JPH071458B2 - Fine displacement mechanism - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fine displacement mechanism for adjusting fine displacement in the fields of semiconductor manufacturing and inspection, high magnification microscopes and the like.

[Conventional technology]

In the fields of semiconductor manufacturing and inspection, high-power microscopes, and the like, a fine displacement mechanism that accurately obtains a fine displacement of several microns or less is necessary. Such a fine displacement mechanism is disclosed in, for example, JP-A-61-209846 and JP-A-61-2435.
It is proposed by the publication No. 11, etc. This will be described below with reference to the drawings.

5 (a) and 5 (b) are side views of a conventional fine displacement mechanism. Of these, FIG. 5 (a) shows a fine displacement mechanism for translational displacement, and 1 and 2 are rigid body parts facing each other and 3
Are two flat plates connecting the rigid bodies 1 and 2. The flat plates 3 are arranged in parallel with each other. These two rigid parts 1,2
The flexible structure 4 is composed of the two flat plates 3. In the actual manufacturing, the flexible structure 4 is constructed by forming a through hole 5 in one rigid block. 6
Is a displacement generating element mounted between two protrusions protruding from the rigid body portions 1 and 2 into the through hole 5, respectively. Since a piezoelectric element is often used as the displacement generating element 6,
Hereinafter, the displacement generating element is represented by a piezoelectric element. Rigid part 1
When the piezoelectric element 6 is excited by fixing the flat plate 3, each flat plate 3 is deformed as shown by a broken line (however, this displacement is exaggeratedly drawn), and the rigid body portion 2 is translationally displaced with respect to the rigid body portion 1. You can

FIG. 5 (b) shows a fine displacement mechanism for rotational displacement.
Reference numeral 2 is a rigid body portion, and 13 is two flat plates connecting the rigid body portions 11 and 12. The flat plates 13 are arranged radially with respect to an axis O perpendicular to the plane of the drawing. Two rigid parts 11,12, two flat plates 1
The flexible structure 14 is composed of 3. Reference numeral 15 is a trapezoidal through hole for forming the flexible structure 14. 16 is a rigid body part
The piezoelectric element is mounted between two protrusions protruding from the insides of the through holes 15 from 11, 12 respectively. When the rigid body portion 11 is fixed and the piezoelectric element 16 is excited, each flat plate 13 is deformed as shown by the broken line (exaggeratedly drawn), and the rigid body portion 12 is deformed with respect to the rigid body portion 11.
Can be rotationally displaced.

By combining a plurality of flexible structures 4 shown in FIG. 5 (a), translational displacement in an arbitrary direction, and by combining a plurality of flexible structures 14 shown in FIG. 5 (b). An arbitrary translational displacement and an arbitrary rotational displacement can be simultaneously obtained by further combining the arbitrary rotational displacement and the flexible structure 4 and the flexible structure 14.

6 (a) and 6 (b) are side views of another conventional fine displacement mechanism. This fine displacement mechanism is shown in FIGS. 5 (a) and 5 (b).
While the fine displacement mechanism shown in (1) has a configuration that utilizes the deformation of the flat plates 3 and 13 itself, it has a configuration that utilizes the deformation of the elastic hinge. Therefore, first, the outline of the elastic hinge will be described with reference to FIGS.

FIG. 7 (a) is a side view of the elastic hinge. Reference numeral 17 is one rigid member, and 18 is a substantially arcuate notch formed facing the intermediate portion of the rigid member 17. A narrow portion 19 is formed in the rigid member 17 by the notches 18, and the rigid member 17 is the narrow portion.
It is divided by 19 into rigid body portions 17a and 17b continuous with this.

FIG. 7 (b) is a side view of another elastic hinge. In the figure,
The same parts as those shown in FIG. 7 (a) are designated by the same reference numerals. 19 'is a narrow space. The narrow portion 19 ′ is formed by one substantially arc-shaped cutout portion 18, while the narrow portion 19 is formed by two facing cutout portions 18.

FIG. 7 (c) is an operation explanatory view of the elastic hinge. In the figure,
Reference numerals 17a and 17b denote the same rigid portions as those shown in FIGS. 7A and 7B, and 20 denotes a hinge point that rotatably connects the rigid portions 17a and 17b.

Now, in FIGS. 7A and 7B, one rigid body portion 17a
Is fixed and a force F in the direction of the arrow in the figure is applied to the other rigid body portion 17b, the rigid body portions 17a and 17b are hardly deformed,
The narrow portions 19 and 19 'are slightly deformed, whereby the rigid body portion 17b is rotationally displaced as shown by the broken line. However, when a force component in a direction other than the force F acts, the narrow portion 19,1
9'has the characteristic of being extremely resistant to deformation. The above characteristics are the same as those of the configuration in which two rigid body portions 17a and 17b are connected at the hinge point 20 as shown in FIG. 7C, within the range of elastic deformation of the narrow portions 19 and 19 '. The narrow portions 19, 19 'are referred to as elastic hinges because they have similar characteristics.

By the way, since the hinge point 20 shown in FIG. 7 (c) is formed by fitting of mechanical parts, even if these mechanical parts are processed with the highest precision, it is not possible to continue the existence of micron-level gaps. Can not. Therefore, it is impossible for the hinge point 20 to generate an error-free displacement when performing a very small displacement. On the other hand, the elastic hinge composed of the narrow portions 19 and 19 'exhibits almost no displacement error within the range of elastic deformation and exhibits ideal hinge characteristics.

In the fine displacement mechanism shown in FIGS. 6 (a) and 6 (b), a flat rigid body having elastic hinges at both ends is used instead of the flat plates 3 and 13 of the fine displacement mechanism shown in FIGS. 5 (a) and 5 (b). To be In FIGS. 6A and 6B, the same parts as those shown in FIGS. 5A and 5B are designated by the same reference numerals. Reference numerals 21 and 31 denote rigid plates, and reference numerals 22 and 32 denote elastic hinges formed by the notches 23 and 33. In this case, the rigid body portions 17a and 17b shown in FIGS. 7A to 7C are the rigid body portions 1 and 11 and the plate-like rigid body portions 21 and 31, or the rigid body portions 2 and 12 and the flat plate-like rigid bodies 21 and 31, respectively. Clearly the equivalent. 24 and 34 are such plate-like rigid bodies 21 and 31, elastic hinges 2
A flexible structure using 2,32 is shown.

These fine displacement mechanisms excite the piezoelectric elements 6 and 16 to cause translational displacement and rotational displacement in the rigid portions 2 and 12, respectively, as shown by the broken lines. The reason why such displacement occurs is considered to be clear from the description of the elastic hinge described above, and thus the description thereof is omitted. It is also clear that any desired displacement can be obtained by using a plurality of these fine displacement mechanisms or using them in combination.

In the fine displacement mechanism shown in FIGS. 6A and 6B, the deformation occurs only in the elastic hinges 22 and 23 and not in the flat plate rigid bodies 21 and 31. Therefore, the flat plate rigid bodies 21 and 31 do not have to be flat plate-shaped, and may have any shape as long as they are rigid bodies. Since such a rigid body constitutes a link mechanism together with an elastic hinge, it can be generally referred to as a rigid body link.

[Problems to be Solved by the Invention]

Each of the fine displacement mechanisms described above can generate displacement with high accuracy. However, the magnitude of the displacement obtained by them is at the same level as the displacement generated in the piezoelectric elements 6 and 16, and it is in the range of several microns to ten and several microns at most. Incidentally, some devices using the fine displacement mechanism require a maximum displacement of several tens of microns to several hundreds of microns. In this case, the above-mentioned fine displacement mechanism cannot obtain such a large displacement. . Therefore, conventionally, in order to obtain a large displacement, after a large displacement is generated by an appropriate coarse displacement mechanism, a highly accurate displacement is obtained using the fine displacement mechanism, or a displacement in the same direction is generated. Means such as stacking the fine displacement mechanisms in a plurality of stages has been adopted.

However, these means have to use a plurality of displacement mechanisms in any case, which causes a problem that the device becomes large and complicated, and it is difficult and expensive to manufacture.

The object of the present invention is to solve the above-mentioned problems in the conventional technology,
It is an object of the present invention to provide a fine displacement mechanism capable of obtaining a large displacement with a simple structure and easily performing a plurality of combinations.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a first rigid body portion, a second rigid body portion, and an elastic hinge that connects the first rigid body portion and the second rigid body portion. In a fine displacement mechanism including at least two connecting rigid links, the at least one of the first rigid portion and the second rigid portion and at least one of the connecting rigid links. It is characterized in that a displacement generating element is connected between the two.

[Action]

When the displacement generating element is excited, the rigid link for coupling connected to the displacement generating element is displaced by the deformation of one elastic hinge of the rigid link for coupling, and the center point of the other elastic hinge of the rigid link for coupling is displaced. Generate a displacement that is magnified to.

〔Example〕

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

FIG. 1 is a side view of the fine displacement mechanism according to the first embodiment of the present invention. In the figure, the same parts as those shown in FIG. 6 (a) are designated by the same reference numerals and the description thereof will be omitted. 40a and 40b are elastic hinges, A ₁ is a deformation center point of the elastic hinge 40a, Q ₁ is a deformation center point of the elastic hinge 40b, P ₁ and Q ₂ are deformation centers of both elastic hinges 22 in one plate-like rigid body. Show points. 41a, 41b
Is a supporting rigid body that is coupled to and supports each end of the piezoelectric element 6, the supporting rigid body 41a being connected to one plate-like rigid body 21 via the elastic hinge 40a, and the supporting rigid body 41b is the elastic hinge 40b. Is connected to the rigid body portion 1 via. A line connecting the points A ₁ and Q ₁ of the elastic hinges 40a and 40b is shown by a one-dot chain line L.

Next, the operation of this embodiment will be described. When the piezoelectric element 6 is excited, the plate-shaped rigid body 21 is pushed at the point A ₁ via the supporting rigid body 41a, and the plate-shaped rigid body 21 rotates about the point P ₁ of the elastic hinge 22. By this rotation, the point Q ₂ of the other elastic hinge 22 is displaced, and as a result, the rigid body portion 2 is translationally displaced with respect to the rigid body portion 1 as shown by the broken line.

Here, a line connecting the center points of the elastic hinges on both ends of the plate-like rigid body 21 Shall orthogonal to the linearly L, and the distance of one of the vertical distance between the center point P ₁ and the straight line L of the elastic hinges 22 a, the center point Q ₂ of the center point P ₁ and the other elastic hinge 22 b, piezoelectric element 6
When δ is the displacement (displacement of the piezoelectric element 6) that occurs at point A ₁ when is excited, δ ′ at point Q ₂ is δ ′ = b · δ / a
Becomes That is, the displacement δ generated in the piezoelectric element 6 is magnified b / a times. Therefore, if the distance a is designed to be as small as possible, a large displacement enlargement ratio can be obtained. Therefore, even it shall apply the point A ₁ is a point of the flat rigid 21 throat, although the displacement magnification changes, it is clear it is possible to obtain an enlarged displacement to the point Q _2.

In the configuration shown in FIG. 1, the elastic hinges 40a and 40b have a relative angle between the flat rigid link 21 and the piezoelectric element 6 when the flat rigid link 21 is slightly rotated when the piezoelectric element 6 is excited. It has a function of absorbing a minute change and limiting the point of action of the piezoelectric element 6 to A ₁ and Q ₁ to keep the displacement magnification ratio constant in the configuration of this embodiment. Further, the structure of this embodiment seems to be difficult to manufacture because its shape is rather complicated, but it can be easily manufactured from one rigid block by wire cutting, which is a kind of electric discharge machining.

In the description of the above embodiment, the straight line L and the line Although an ideal arrangement in which and are orthogonal to each other has been illustrated, the present invention is not limited to this, and it is clear that the function of generating displacement is exhibited unless the two are parallel and do not match.

As described above, in this embodiment, the existing flat plate rigid body and its elastic hinge are used as the enlarging mechanism, and the displacement of the piezoelectric element is enlarged by the enlarging mechanism. Therefore, a large translational displacement can be obtained with a simple configuration. be able to. In addition, since the mechanism for expanding the displacement is not housed in the area and does not project to the outside,
When a plurality of single fine displacement mechanisms are coupled to form a multiple axis fine displacement mechanism, the coupling can be easily performed.

FIG. 2 is a side view of the fine displacement mechanism according to the second embodiment of the present invention. In the figure, the same parts as those shown in FIG. 6'is a second piezoelectric element which is the same as the piezoelectric element 6, 40a 'and 40b' are elastic hinges, 41
Reference numerals a ′ and 41b ′ are support rigid bodies that support the piezoelectric element 6 ′.
The elastic hinges 40a ', 40b' are the same as the elastic hinges 40a, 40b, and the supporting rigid bodies 41a ', 41b' are the same as the supporting rigid bodies 41a, 41b. This embodiment is different from the first embodiment in that
The same piezoelectric element 6'as in the first embodiment, its supporting rigid bodies 41a ', 41b', and elastic hinges 40a ', 40b' are symmetrically added.

The displacement magnifying power of this embodiment when the piezoelectric elements 6 and 6'are excited is the same as the displacement magnifying power b / a of the first embodiment.
However, when the displacement of the first embodiment is magnified b / a times, the force generated by the piezoelectric element 6 is a / a at the point Q ₂ .
In the present embodiment, the force at the point Q ₂ can be doubled as compared with the force in the first embodiment, while it is reduced to b.

In the description of the above embodiment, an ideal configuration in which two pairs of the same piezoelectric element, supporting rigid body, and elastic hinge are symmetrically arranged is illustrated, but the present invention is not limited to this, and for example, point A ₁ (point of action ) May be a position other than the symmetrical position, and the length or expansion rate of the piezoelectric element may be selected according to the position. And in this case, both piezoelectric elements are not the same. In addition, when the above-mentioned two sets are all the same in configuration but each arrangement is not exactly symmetrical and there is some deviation, if the deviation is small, it is sufficiently absorbed by expansion and contraction of the piezoelectric element and no particular trouble occurs. .

By adopting the above-mentioned configuration, this embodiment not only achieves the same effect as the first embodiment, but also can secure a larger force during displacement.

FIG. 3 is a side view of the fine displacement mechanism according to the third embodiment of the present invention. In the figure, the same parts as those shown in FIG. 6 (b) are designated by the same reference numerals and the description thereof will be omitted. 50a and 50b are first
It is the same elastic hinge as the elastic hinges 40a, 40b shown in the figure,
The deformation center points of these elastic hinges 50a and 50b are designated by the same reference numerals A ₁ and Q _{1 as} the deformation center points of the elastic hinges 40a and 40b.
51a and 51b are the same support rigid bodies as the support rigid bodies 41a and 41b shown in FIG. Also in this embodiment, the straight line L connecting the points A ₁ and Q ₁
(Indicated by a chain line) and a line connecting the deformation center points P ₁ and Q ₂ of the elastic hinges 32 at both ends of the plate-shaped rigid body 31. And are orthogonal to each other. Therefore, unlike the case shown in FIG. 6B, the piezoelectric elements 16 are arranged at different angles with respect to the flat plate-like rigid bodies 31 radially arranged with respect to the point O.

In the present embodiment and the first embodiment, the flat plate rigid bodies 21 of the first embodiment are arranged in parallel with each other, whereas the flat plate rigid body 31 of the present embodiment has a point O (see FIG. (b) but not shown in FIG. 3), and that the first embodiment produces a translational displacement between the rigid bodies 1,2, The other operations are the same, except that a rotational displacement is generated between the rigid body portions 11 and 12. That is, the displacement [delta] is generated in the point A ₁ and deformed to the point P ₁ when exciting the piezoelectric element 16, the displacement [delta] 'In this displacement [delta] is the point Q ₂
It is expanded to (δ ′ = b · δ / a). As a result, the rigid part 12
Is rotationally displaced with respect to the rigid body portion 11 as shown by a broken line.

Since the present embodiment has the above-described structure, it is possible to obtain a large rotational displacement with a simple structure as in the first embodiment. In addition, when a plurality of single fine displacement mechanisms are coupled to form a multi-axis fine displacement mechanism, the coupling can be easily performed.

FIG. 4 is a side view of the fine displacement mechanism according to the fourth embodiment of the present invention. In the figure, the same parts as those shown in FIG. 16 'is a second piezoelectric element which is the same as the piezoelectric element 16, 50a' and 50b 'are elastic hinges, 51
Reference numerals a ′ and 51b ′ are support rigid bodies that support the piezoelectric element 16 ′.
The elastic hinges 50a ', 50b' are the same as the elastic hinges 50a, 50b, and the supporting rigid bodies 51a ', 51b' are the same as the supporting rigid bodies 51a, 51b. This embodiment is different from the first embodiment in that the piezoelectric element 6'and its supporting rigid bodies 41a ', 41 are further added.
Similarly to the case where b ′ and elastic hinges 40a ′ and 40b ′ are added at symmetrical positions, the piezoelectric element 1 is further added to that of the third embodiment.
6 ', its supporting rigid bodies 51a', 51b 'and elastic hinges 50a',
50b 'is added. The displacement magnifying rate of this embodiment is also b / a as in the third embodiment,
The force at the point Q ₂ is _twice the force in the third embodiment. Further, similarly to the second embodiment, the arrangement position of each set of the piezoelectric element, the supporting rigid body, and the elastic hinge is not symmetrical, or the piezoelectric elements may not be the same.

By adopting the above-mentioned configuration, this embodiment not only achieves the same effect as the third embodiment, but also can secure a larger force during displacement.

In the description of each of the above embodiments, a plate-shaped rigid body is illustrated as a member that connects two rigid body portions, and a piezoelectric element is illustrated as a displacement generation element. It has already been mentioned that it is not limited to the element. Further, in the description of each of the above-described embodiments, an example in which the supporting rigid body that supports the displacement generating element is connected to another via an elastic hinge has been described. However, such an elastic hinge serves as a displacement target of the present invention. Even if it is omitted in the range of displacement, there may be a case where practically no inconvenience occurs. In this case, naturally, the supporting rigid body can be directly connected to another.

〔The invention's effect〕

As described above, in the present invention, the existing rigid link for connection and the elastic hinges at both ends thereof are used as the displacement magnifying mechanism, so that a large displacement can be obtained with a simple configuration. In addition, since the displacement magnifying mechanism is not housed in the area and does not project to the outside, when a plurality of single fine displacement mechanisms are combined to form a multi-axis fine displacement mechanism, the connection should be performed easily. You can

[Brief description of drawings]

1, FIG. 2, FIG. 3 and FIG. 4 are side views of the fine displacement mechanism according to the first, second, third and fourth embodiments of the present invention, respectively, FIG. 5 (a), (B), FIG. 6 (a),
FIG. 7B is a side view of a conventional fine displacement mechanism, and FIGS. 7A, 7B, and 7C are side views and operation explanatory views of an elastic hinge. 1,2,11,12 …… Rigid body part, 6,6 ′, 16,16 ′ …… Piezoelectric element, 2
1,31 …… Rigid plate, 22,32,40a, 40b, 40a ′, 40b ′, 50a,
50b, 50a ', 50b' ... Elastic hinges.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Ken Murayama, 650 Jinrachicho, Tsuchiura, Ibaraki Prefecture Tsuchiura Plant, Hitachi Construction Machinery Co., Ltd. (56) References JP 61-243511 (JP, A) JP 59-175387 (JP, A) JP 58-81606 (JP, U)

Claims (5)

[Claims] 1. A first rigid body portion, a second rigid body portion, and at least two coupling rigid body links that couple the first rigid body portion and the second rigid body portion via elastic hinges. In the fine displacement mechanism, a displacement generating element is coupled between at least one of the first rigid body portion and the second rigid body portion and at least one of the coupling rigid body links. Displacement mechanism. 2. The fine displacement mechanism according to claim 1, wherein the connecting rigid links are arranged in parallel with each other. 3. The fine displacement mechanism according to claim (1), wherein the connecting rigid links are arranged radially with respect to a predetermined axis. 4. A fine displacement mechanism according to claim 1, wherein the displacement generating element is a piezoelectric element. 5. The microscopic device according to claim 1, wherein the displacement generating element is connected to the first rigid portion and the connecting rigid link via an elastic hinge. Displacement mechanism.