JPH071459B2 - 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.

4 (a) and 4 (b) are side views of a conventional fine displacement mechanism. Of these, FIG. 4 (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. 4 (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. 4 (a), translational displacement in an arbitrary direction, and by combining a plurality of flexible structures 14 shown in FIG. 4 (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.

5A and 5B are side views of another conventional fine displacement mechanism. This fine displacement mechanism is shown in FIGS. 4 (a) and 4 (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. 6 (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 rigid portion 17 is formed with a rigid portion 17 by the notches 18, and the rigid member 17 is divided by the rigid portion 19 into rigid portions 17a and 17b continuous with the rigid portion 17.

FIG. 6 (b) is a side view of another elastic hinge. In the figure,
The same parts as those shown in FIG. 6 (a) are designated by the same reference numerals. 19 'is a head office. The claw portion 19 ′ is formed by one substantially arcuate notch portion 18, while the previous claw portion 19 is formed by two facing notch portions 18.

FIG. 6 (c) is an operation explanatory view of the elastic hinge. In the figure,
Reference numerals 17a and 17b denote the same rigid body portions as shown in FIGS. 6A and 6B, and 20 denotes a hinge point that rotatably connects the rigid body portions 17a and 17b.

Now, referring to FIGS. 6A and 6B, 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 claws 19 and 19 'are slightly deformed, whereby the rigid 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 claws 19,1
9'has the characteristic of being extremely resistant to deformation. The above characteristics are characteristics of a structure in which two rigid body portions 17a and 17b are connected at a hinge point 20 as shown in FIG. 6C, within the range of elastic deformation of the claw portions 19 and 19 '. Since the same characteristic is exhibited, the claw portions 19 and 19 'are referred to as elastic hinges.

By the way, since the hinge point 20 shown in FIG. 6 (c) is formed by fitting of mechanical parts, even if these mechanical parts are processed with the highest precision, it is not possible to avoid 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 claws 19 and 19 'shows almost no displacement error within the range of elastic deformation and exhibits an ideal hinge characteristic.

In the fine displacement mechanism shown in FIGS. 5 (a) and 5 (b), a flat plate 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. 4 (a) and 4 (b). To be 5 (a) and 5 (b), the same parts as those shown in FIGS. 4 (a) and 4 (b) 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. 6 (a) to (c) become rigid body portions 1 and 11 and flat plate-like rigid body portions 21 and 31, or rigid body portions 2 and 12 and flat plate-like rigid body 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. 5A and 5B, the deformation occurs only in the elastic hinges 22 and 32, and not in the flat plate rigid bodies 21 and 31. Therefore, the plate-shaped rigid bodies 21 and 31 do not have to be plate-shaped, and any shape may be used as long as they are rigid bodies. Since such a rigid body constitutes a link mechanism together with an elastic hinge, it can generally be 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 that can obtain a large displacement by itself and can make a plurality of couplings easily without enlarging the entire structure.

[Means for Solving the Problems] In order to achieve the above object, the present invention connects a first rigid body portion, a second rigid body portion, and the first rigid body portion and the second rigid body portion. In a fine displacement mechanism including at least two connecting rigid links, the first rigid body is provided in a region surrounded by the first rigid body portion, the second rigid body portion, and two connecting rigid body links. A displacement magnifying rigid link connected to the portion via a coupling elastic hinge, and a first point on the displacement magnifying rigid link located between the first rigid body portion and the second rigid body portion. The displacement generating element connected between the first rigid body portion and the displacement enlargement rigid link on the displacement enlarging rigid link whose distance from the displacement center point of the connecting elastic hinge is longer than the distance to the first point. Displacement for transmitting displacement of two points to one of the connecting rigid links And a transmission member.

[Action]

When the displacement generating element is excited, the first point on the displacement magnifying rigid link is displaced by the deformation of the connecting elastic hinge coupled to the displacement magnifying rigid link, and this displacement is for the displacement magnifying. It appears magnified at the second point on the rigid link. The displacement of the second point is transmitted to the intermediate portion of one connecting rigid link by the displacement transmitting member to displace the connecting rigid link. This displacement is expanded and transmitted to the second rigid body portion by the connecting rigid body link to displace it.

〔Example〕

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

FIG. 1 is a plan view of a fine displacement mechanism according to the first embodiment of the present invention. In the figure, the same parts as those shown in FIG. 40a, 40b, 40c, 40
Reference numerals d and 40e indicate elastic hinges, and the reference numerals in parentheses attached to the reference numerals indicate the names attached to the deformation center points of the elastic hinges. Reference numeral 41 denotes a rigid link for expanding displacement, which is connected to the rigid part 1 via an elastic hinge 40a. Reference numerals 42a and 42b denote supporting rigid bodies that are coupled to and support the respective ends of the piezoelectric element 6, the supporting rigid body 42a being connected to the rigid body link 41 via an elastic hinge 40b, and the supporting rigid body 42b being via an elastic hinge 40c. And is connected to the rigid body portion 1. Each elastic hinge 40b, 40c
A line connecting the points A ₁ and Q ₁ is indicated by a one-dot chain line L. Reference numeral 43 denotes a displacement transmission member that transmits the displacement of the rigid link 41 to the one plate-shaped rigid body 21. The displacement transmitting member 43 has one end connected to the rigid link 41 via the elastic hinge 40d and the other end connected to the one plate-shaped rigid body 21 via the elastic hinge 40e. In such a configuration, the point P ₁ is not on the straight line L, and the distance between the point P ₁ and the point B ₁ is from the point P ₁ to the straight line L and the straight line. Greater than the distance to the intersection with.

Next, the operation of this embodiment will be described. When the piezoelectric element 6 is excited, the rigid link 41 is pushed at the point A ₁ via the supporting rigid body 42a, and the rigid link 41 rotates about the point P ₁ of the elastic hinge 40a. This rotation causes the point B _{1 to} be displaced, and this displacement is transmitted to the point A ₂ via the displacement transmitting member 43. Therefore, the plate-shaped rigid body 21 rotates around the point P ₂ of the elastic hinge 22, and thereby the point Q ₂ of the other elastic hinge 22 of the plate-shaped rigid body 21 is displaced. As a result, the rigid body portion 2 is translationally displaced with respect to the rigid body portion 1.

In the above operation, the displacement of the piezoelectric element 6 appears as the displacement of the point A ₁ , but this displacement is caused by the rigid link 41 and the elastic hinge.
With 40a, it appears enlarged at point B ₁ at the other end of rigid link 41. The enlarged displacement is transmitted to the point A _2, the the one of the elastic hinge 22 displaced a flat rigid body 21 of the point A _2, appears is further expanded in terms Q ₂ of the other elastic hinge. Eventually, the displacement of the piezoelectric element 6 is magnified twice, and the magnified displacement appears at the point Q ₂ .

By the way, in this embodiment, since the rigid link 41 and the elastic hinge 40a constitute one expansion mechanism, the other end of the rigid link 41 (the end opposite to the elastic hinge 40a) is temporarily connected to the rigid portion 2. Then, the displacement enlarged in the rigid body portion 2 can be obtained by the enlargement mechanism. And the magnification point of this expansion is the line from P ₁ to L. It is clear that the distance becomes larger by decreasing the distance to the intersection with and increasing the distance from the point P ₁ to the point B ₁ . However, each of the above distances is naturally subject to design restrictions when constructing the fine displacement mechanism. Therefore, when one expanding mechanism including the rigid link 41 and the elastic hinge 40a is used as described above, The magnification of displacement displacement is several times at most, and it is impossible to obtain displacement of several hundreds of microns. On the other hand, in this embodiment, the existing plate-shaped rigid body 21
Since the elastic hinge 22 and the elastic hinge 22 are used as the second enlargement mechanism and the displacement enlarged by the previous enlargement mechanism is further enlarged by the second enlargement mechanism, the enlargement ratio is dramatically increased. It is possible to make a displacement of several hundreds of microns.

The elastic hinges 40b, 40c in the configuration shown in FIG.
Absorbs the small displacement of the relative angle generated between the rigid link 41 and the piezoelectric element 6 when the piezoelectric element 6 is excited and the rigid link 41 makes a minute rotation, and the point of action of the piezoelectric element 6 is set to the point A ₁ , Q ₁ , which has a function of holding the displacement magnification ratio constant in the configuration of the present embodiment. More elastic hinge
Due to the existence of 40d and 40e, rigid link 4
Since it is possible to absorb a minute change in the relative angle between the 1 and the displacement transmitting member 43 and between the flat rigid body 21 and the displacement transmitting member 43, the position of the point A ₂ is not limited. As a result, the distance between the points P ₂ and A ₂ can be shortened to improve the magnification. Further, the structure of the present embodiment seems to be difficult to manufacture because of its complicated shape, but it can be easily manufactured from one rigid block by wire cutting, which is a kind of electric discharge machining.

As described above, in this embodiment, the expansion mechanism including the rigid link and the elastic hinge is configured, and the existing plate-shaped rigid body and the elastic hinge are used as another expansion mechanism, and the displacement of the piezoelectric element is increased by the above two expansions. Since the mechanism is used for enlarging, an extremely large displacement can be obtained as compared with a single fine displacement mechanism. Further, by arranging all the members newly added for expanding the displacement in the through holes, the entire structure can be made compact. Further, since the structure for accommodating in the through hole can eliminate the protrusion of the expansion displacement mechanism to the outside, the whole structure is small, and in order to obtain the displacement of multiple axes, a single fine When a plurality of displacement mechanisms are combined, the combination can be easily configured.

FIG. 2 is a side view of the fine displacement mechanism according to the second embodiment of the present invention. In the figure, parts having the same functions as those shown in FIG. 1 are designated by the same reference numerals. Reference numeral 43a denotes a through hole or a notch formed in the displacement transmitting member 43, into which the piezoelectric element 6 is inserted. Reference numeral 44 denotes a protruding portion of the rigid body portion 1 protruding into the through hole 5. Reference numeral 45 denotes a recess formed in the rigid body portion 1, and the opening of the recess 45 faces the through hole 5. The present embodiment differs from the previous embodiment in that the previous embodiment uses the piezoelectric element 6 in the longitudinal direction of the through hole 5 (direction perpendicular to the plate-shaped rigid body 21).
However, in the present embodiment, the piezoelectric element 6 is arranged diagonally across the through hole 5. Since the arrangement position of the piezoelectric element 6 is changed in this way, the protrusion 44 and the recess 45 are separately provided, and the elastic hinges 40a, 40b,
The arrangement positions of 40d and the displacement transmitting member 43 have changed.
However, the operation is the same as the previous embodiment,
Also, since the effects are the same, their explanations are omitted.
The piezoelectric element 6 and the displacement transmitting member 43 can be arranged so as to be displaced from each other in the direction perpendicular to the paper surface, and in that case, the through hole or the cutout portion 43a is unnecessary.

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. 5 (b) are designated by the same reference numerals. 50a, 50b, 50c, 50d, 50e are the same elastic hinges as the elastic hinges 40a, 40b, 40c, 40d, 40e shown in FIG. 1, respectively, with respect to the deformation center points of these elastic hinges 50a-50e, The same symbols as the deformation center points of the corresponding elastic hinges 40a to 40e shown in FIG. 1 are given in parentheses. Reference numeral 51 is a rigid link, 52a and 52b are support rigid bodies, and 53 is a displacement transmitting member, which correspond to the rigid link 41, supporting rigid bodies 42a and 42b, and displacement transmitting member 43 shown in FIG. 1, respectively.

When the piezoelectric element 16 is excited, its displacement is magnified by the displacement magnifying mechanism composed of the rigid link 51 and the elastic hinge 50a to appear at the point B ₁ , and the magnified displacement is the displacement transmitting member.
It is transmitted to the point A ₂ by 53, and the transmitted displacement is further magnified by the displacement magnifying mechanism composed of the flat plate rigid body portion 31 and the elastic hinge 32 and appears at the point Q ₂ . As a result, the rigid body portion 12 is rotationally displaced with respect to the rigid body portion 11.

Since such an operation is the same as the operation of the fine displacement mechanism shown in FIG. 1 and the effect is also the same, detailed description thereof will be omitted. Further, the configuration shown in FIG. 2 can be applied to the present embodiment, but since this is apparent at a glance, its illustration and description will be omitted.

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 substantially no inconvenience. In this case, the supporting rigid body can be directly connected to another.

〔The invention's effect〕

As described above, according to the present invention, the displacement magnifying mechanism configured by the displacement magnifying rigid link and the coupling elastic hinge coupled thereto, and the displacement magnifying mechanism using the existing coupling rigid link and the elastic hinge. As a result, the displacement generated in the displacement generating element is expanded to two stages, so that an extremely large displacement can be obtained by the single fine displacement mechanism. Further, by disposing the displacement magnifying mechanism in a region surrounded by the first rigid body portion, the second rigid body portion, and the two rigid body links for connection, the entire structure can be made compact. Furthermore, by arranging the displacement magnifying mechanism in the above area, it is possible to eliminate the protrusion of the magnifying displacement mechanism to the outside. When a plurality of the fine displacement mechanisms of 1 are combined, the combination can be easily configured.

[Brief description of drawings]

1, 2, and 3 are side views of the fine displacement mechanism according to the first, second, and third embodiments of the present invention, respectively, and FIGS. 4 (a), (b), and FIG. (A), (b) is a side view of the conventional fine displacement mechanism, FIG. 6 (a), (b),
(C) is a side view and an operation explanatory view of the elastic hinge. 1,2,11,12 …… Rigid body part, 6,16 …… Piezoelectric element, 21,31 …… Plate-like rigid body, 22,32,40a to 40e, 50a to 50e …… Elastic hinge, 4
1,51 …… Rigid link, 43,53 …… Displacement transmission member.

 ─────────────────────────────────────────────────── ─── 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 fine displacement mechanism including a first rigid body portion, a second rigid body portion, and at least two coupling rigid body links coupling the first rigid body portion and the second rigid body portion,
A displacement magnifying rigid body coupled to the first rigid body portion via a coupling elastic hinge in a region surrounded by the first rigid body portion, the second rigid body portion, and the two coupling rigid body links. A link, and a first link located between the first rigid part and the second rigid part and located on the displacement magnifying rigid link.
And the displacement generating element connected between the first rigid body portion and the displacement generating element, and the distance from the displacement center point of the connecting elastic hinge is longer than the distance to the first point. A fine displacement mechanism, comprising: a displacement transmitting member that transmits the displacement of the second upper point to one of the connecting rigid links. 2. A fine displacement mechanism according to claim (1), characterized in that the rigid links for connection 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 displacement generating element according to claim 1, wherein the displacement generating element is connected to the first rigid body portion and the displacement expanding rigid body link via an elastic hinge. Fine displacement mechanism.