JPH05188164A - Body moving minute distance and moving method thereof - Google Patents

Abstract

PURPOSE:To make a moving body able to move regardless of friction even if the friction between the moving body and fixed table is large. CONSTITUTION:An upper fixing plate 2 and a lower fixing plate 2' comprising conductors are provided. A movable piece 5 comprising a conductor is provided between the upper fixing plate 2 and the lower fixing plate 2'. One or both of the facing surfaces of the upper fixing plate 2 and lower fixing plate 2' and the movable piece 5 are coated with an insulating thin film 7. A base 8 has a plurality of supporting springs 9, which are protruding to the lower surface of the lower fixing plate 2' with a specified angle. The base 8 is fixed to the lower fixing plate 2', A voltage is applied across the lower fixing plate 2' and the movable piece 5, and the impact force caused by electrostatic attracting force is applied on the lower fixing plate 2'. Thus, the supporting springs 9 are deformed, and the moving body 1 is moved in the horizontal direction. Immediately after the movement, the voltage across the lower fixing plate 2' and the movable piece 5 is made to be 0. A voltage is applied across the upper fixing plate 2 and the movable piece 5, and the impact force is applied on the upper fixing plate 2. Thus, the moving body 1 is floated. The deformation of the supporting springs 9 is returned to the original state, and the moving body 1 is moved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention utilizes electrostatic attraction to
The present invention relates to a minute distance moving body that continuously moves an object by a minute distance.

[0002]

2. Description of the Related Art Conventionally, as a highly accurate positioning device utilizing impact force, the presence of friction is positively utilized to give a minute impact to a stationary moving object to cause a minute movement. Then, there is a method in which a moving object is precisely positioned by repeating this. This is because an inertial body is fixed to a moving object under the action of a frictional force via a cushioning material such as a spring, and, for example, an impact current is applied to a conductor provided on the moving object so that the moving body and the inertial body are separated from each other. To generate a shocking repulsive force between them, or to insert a piezoelectric element between a moving object and an inertial body and apply a shocking voltage to the piezoelectric element to generate a shocking repulsive force. Then, an impact force is applied to the moving object to make a minute movement (for example, Japanese Patent Laid-Open No. 60-60582).

[0003]

SUMMARY OF THE INVENTION However, a device that gives a minute impact to a stationary object by friction to cause a minute movement has a problem that it does not move if the friction is too large, and a piezoelectric element. It is necessary to provide a mechanism for generating an impact force, such as an inertial body or the like, separately from the moving object, and there is a drawback that the driving device becomes large. It is an object of the present invention to provide a moving mechanism for moving a minute distance, which has a simple structure and is compact.

[0004]

According to the present invention, in a moving body which is moved by an impact force, an upper fixing plate and a lower fixing plate made of a conductor are provided, and a conductive member is provided between the upper fixing plate and the lower fixing plate. A movable piece composed of a body is provided, and one or both surfaces of the upper fixed plate, the lower fixed plate, and the movable piece that face each other are covered with an insulating thin film, and at a predetermined angle with respect to the lower surface of the lower fixed plate. A base having a plurality of projecting support springs is fixed to the lower fixing plate. In particular, a plurality of spacers provided around the upper fixing plate and the lower fixing plate maintain a predetermined space between the upper fixing plate and the lower fixing plate, and the spacer can be vertically displaced. A leaf spring is supported, and a mover facing the upper fixed plate and the lower fixed plate via a gap is supported by the leaf spring.
In the method of moving the moving body by impact force, the support spring is deformed by applying a voltage between the lower fixed plate and the movable piece to apply an impact force by electrostatic attraction to the lower fixed plate. Immediately after that, the applied voltage between the lower fixed plate and the movable piece is set to 0, and a voltage is applied between the upper fixed plate and the movable piece to apply an impact force to the upper fixed plate. The moving body is levitated, the deformation of the support spring is restored, and the moving body is moved.

[0005]

When a pulsed voltage is applied between the lower fixed plate and the movable piece, the movable piece collides with the lower fixed plate by electrostatic attraction. By this impact force, the moving body is pressed against the fixed table, and the support spring is bent and deformed. Due to this deformation, the upper part of the support spring moves horizontally. Next, after the voltage between the lower fixed plate and the movable piece is set to 0, when a voltage is applied between the upper fixed plate and the movable piece, the movable piece collides with the upper fixed plate by electrostatic attraction as before. The collision force keeps the position of the upper part of the moving body as it is and levitates. The support spring returns to its original shape due to the floating of the moving body, and then the moving body lands on the fixed table by free fall. At this time,
The moving body moves horizontally by the amount of deformation in the moving direction of the support spring. Since the pulsed voltage applied to the upper fixed plate and the lower fixed plate is applied with a slight timing shift, the moving operation of the moving body can be continuously performed.

[0006]

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a side sectional view showing an embodiment of the present invention, and FIG. 2 is a plan view showing a part of it cut away. The moving body 1 is provided with an upper fixing plate 2 and a lower fixing plate 2'made of a conductor such as stainless steel or aluminum, and four corners are provided between the upper fixing plate 2 and the lower fixing plate 2 '. Spacers 3 and 3'provided between the spacers 3 and 3'are provided, and zigzag-shaped leaf springs 4 which are sandwiched and supported and can be displaced in the vertical direction are provided between the spacers 3 and 3 '. On both sides of the leaf spring 4, a movable piece 5 also made of a conductor is fixed so as to face the upper fixed plate 2 and the lower fixed plate 2'via gaps 6 and 6 '. The upper fixed plate 2, the lower fixed plate 2 ′ and the movable piece 5 are provided with lead terminals 21, 21 ′ and 51 for applying a voltage, respectively. The upper fixing plate 2, the lower fixing plate 2'and the spacers 3 and 3'are fixed by adhesion or the like, and the upper fixing plate 2 and the lower fixing plate 2'or the movable piece 5 are attached.
Either or both of them are covered with an insulating thin film 7 such as SiO ₂ as shown by a thick line. Therefore, when the movable piece 5 is displaced by the electrostatic attraction generated when a voltage is applied between the upper fixed plate 2 or the lower fixed plate 2 ′ and the movable piece 5, the movable piece 5 is movable with the upper fixed plate 2 or the lower fixed plate 2 ′. The pieces 5 are prevented from coming into direct contact with each other. A plate-shaped base 8 is fixed to the lower surface of the lower fixing plate 2 ′, and a support spring 9 made of a plurality of whiskers or plate-shaped elastic bodies protruding at a predetermined angle is provided on the lower surface of the base 8 to fix the fixed table 10. The moving body 1 is placed on top. The operation of moving the moving body 1 having the above configuration will be described with reference to FIG. FIG. 3A shows a state in which the moving body 1 is stationary. In this state, when a voltage V is applied between the lower fixed plate 2 ′ and the movable piece 4, the movable piece 5 collides with the lower fixed plate 2 ′ by electrostatic attraction. However, since the insulating thin film 7 is covered, the gap length between the movable piece 4 and the lower fixed plate 2 ′ at the time of collision does not become zero. The collision force F at this time is defined by a gap length d between the movable piece 4 and the lower fixed plate 2 ′ at the time of collision, an area where the lower fixed plate 2 ′ and the movable piece 4 face each other is A,
When the permittivity is ε, it is expressed by the following formula 1.

[0008]

[Equation 1]

The impact force F pushes the moving body 1 toward the fixed table 10, and the supporting spring 9 is moved to the position shown in FIG.
It is curved and deformed as shown in FIG. Due to this deformation, the upper part of the moving body 1 (upper and lower fixed plates 2, 2 ', the movable piece 4,
The leaf spring 3 and the like) move in the horizontal direction by the movement amount y, but when the spring constant of the support spring 9 is K, it is roughly expressed by the following mathematical formula 2.

[0010]

[Equation 2]

Immediately after the maximum deformation of the support spring 9,
If the voltage V is applied between the upper fixed plate 2 and the movable piece 5 after the voltage between the lower fixed plate 2'and the movable piece 5 is set to 0, the movable piece 5 is moved by the electrostatic attraction force as in the previous case. Clash with. The collision force causes the moving body 1 to levitate at a position horizontally moved by a movement amount y. The flying height h is represented by the following mathematical formula 3 when the spring force of the leaf spring 4 supporting the movable piece 5 and the gravitational acceleration are ignored.

[0012]

[Equation 3]

By this levitation, the support spring 9 returns to its original shape as shown in FIG. 3 (c), and then the movable body 1 is fixed to the fixed table 10 by free fall as shown in FIG. 3 (d).
Land on top of. At this time, the moving body 1 moves by the horizontal movement amount y. It should be noted that the movement amount y is obtained by substituting the equation 1 into the equation 2. When the actual value is calculated, the dielectric constant ε ＝ 8.85 × 10 ^-12 F / m, the moving piece density ρ
= 7850kg / m ³ , movable piece thickness t = 5 × 10 ^-3 m, area A = 50
× 10 ^-6 m ² , voltage V = 200 V, initial gap length X = 19 × 10 ^-6 m between the movable piece 4 and the upper fixed plate 2, vertical movement distance X ₀ = 20 × 10 ^{− of the} movable piece 4. ⁶ m, movable piece 4 and lower fixed plate 2'at the time of collision
The gap length d = 1 × 10 ^-6 m, the angle of the leaf spring with the fixed table θ = 45 °, the spring constant K = 10 ⁵ N / m, the mass excluding the movable piece and the mass of the movable piece. If the ratio m / M = 2 and the acceleration of gravity g = 9.8 m / s ² , the moving amount y = 0.045 mm and the flying height h = 0.1 mm. In order to continuously perform the above operation, a controller (not shown) is used to slightly shift the timings of the pulsed voltages between the upper fixed plate, the lower fixed plate and the movable piece as shown in FIG. Apply continuously. Although the movable piece 5 is supported by the leaf spring 4 in the embodiment of FIG. 1, even if the leaf spring 4 is not provided, the movable piece 5 is shocked to the fixed plate by the electrostatic attraction force between the fixed plate and the movable piece. The force in the vertical direction acts to bend the leaf spring and move the moving body. Alternatively, the upper and lower fixed plates or the movable piece may be made of an insulator instead of a conductor, and the surfaces facing each other may be coated with a conductor, and the leads may be connected to the coating.

[0014]

As described above, according to the present invention, the plate-like support springs projecting at a predetermined angle are provided on the lower surface of the base fixed to the lower surface of the lower fixing plate to move the upper and lower fixing plates. By applying a pulsed voltage between the
Since the moving body is floated and moved in the bending direction of the support spring, even when the friction between the moving body and the fixed table is large, the moving body can move regardless of the friction. Further, since the upper and lower fixed plates and the movable piece are provided with electrodes for inducing static electricity, there is an effect that a small moving mechanism having an extremely thin structure and a simple structure can be provided.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention.

FIG. 2 is a plan view of FIG. 1 with a part cut away.

FIG. 3 is a side sectional view showing the operation of the embodiment of the present invention.

FIG. 4 is an explanatory diagram showing timings of pulsed voltages applied to an upper fixing plate and a lower fixing plate according to an embodiment of the present invention.

[Explanation of symbols]

1 moving body 2 upper fixed plate 2'lower fixed plate 3, 3'spacer 4 leaf spring 5 movable piece 6, 6'gap 7 insulating thin film 8 base 9 support spring 10 fixed table

Claims (3)

[Claims] 1. A moving body that moves by an impact force,
An upper fixing plate and a lower fixing plate made of a conductor are provided, and a movable piece made of a conductor is provided between the upper fixing plate and the lower fixing plate,
One or both surfaces of the upper fixed plate, the lower fixed plate, and the movable piece facing each other are covered with an insulating thin film, and a plurality of support springs projecting at a predetermined angle with respect to the lower surface of the lower fixed plate are provided. And a base fixed to the lower fixing plate. 2. A plurality of spacers provided around the upper fixing plate and the lower fixing plate maintain a predetermined distance between the upper fixing plate and the lower fixing plate, and the spacer is vertically arranged. The minute distance moving body according to claim 1, wherein a movable element that supports a displaceable plate spring and that opposes the upper fixed plate and the lower fixed plate via a gap is supported by the plate spring. 3. A method of moving a moving body by a small distance by impact force, wherein an upper fixing plate and a lower fixing plate made of a conductor are provided, and a movable member made of a conductor is provided between the upper fixing plate and the lower fixing plate. A plurality of pieces, the upper fixed plate and the lower fixed plate, and one or both surfaces of the movable piece that face each other are covered with an insulating thin film, and a plurality of pieces project at a predetermined angle with respect to the lower surface of the lower fixed plate. The base provided with a support spring is fixed to the lower fixed plate, and a voltage is applied between the lower fixed plate and the movable piece to apply an impact force due to electrostatic attraction to the lower fixed plate, thereby supporting the support spring. Immediately after the deformation, the applied voltage between the lower fixed plate and the movable piece is set to 0, and a voltage is applied between the upper fixed plate and the movable piece to apply an impact force to the upper fixed plate. In addition, the movable body is levitated, and based on the deformation of the support spring, A method for moving a minute distance moving body, which is characterized by returning the moving body and moving the moving body.