JP3458227B2 - Stage mechanism - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stage mechanism in which a moving body moves on a guide, and more particularly to a structure support structure used in the stage mechanism.

[0002]

2. Description of the Related Art Generally, there is known a stage mechanism in which a moving body moves along a guide.

A conventional stage mechanism will be described with reference to FIG.

The illustrated stage mechanism is a uniaxial stage mechanism using a hydrostatic bearing, and one beam 6 is fixed on the base 1. A moving body 14 is arranged on the beam 6, and the moving body 14 can move along the beam 6 using the beam 6 as a guide. In the illustrated stage mechanism, the beam 6 and the moving body 14 are made of a material such as ceramic, which is easy to control in size and has high rigidity.

Further, as a stage mechanism, a biaxial stage mechanism using a hydrostatic bearing shown in FIG. 4 is known.
Referring to FIG. 4, two rails 2 and 3 are provided on the base 1.
Are arranged at a predetermined interval. Rails 2 and 3
The mobile bodies 4 and 5 are arranged in the respective mobile stations, and the mobile bodies 4 and 5 move (move) along the rails 2 and 3, respectively. The moving bodies 4 and 5 are connected by the beam 6, and as a result, the beam 6 also moves as the moving bodies 4 and 5 move on the rails 2 and 3. The moving body 14 is arranged on the beam 6, and the moving body 14 uses the beam 6 as a guide.
You can move along.

[0006]

By the way, in recent years, the stage mechanism tends to be large in size, and in order to increase the moving amount (stroke) of the moving body 14 in both the stage mechanism shown in FIGS. 3 and 4, the beam 6 is used. Is longer, and the load mass mounted on the moving body 14 is larger. As a result, the deflection amount of the beam 6 is a non-negligible amount. When such a deflection occurs, the moving body cannot move smoothly.

Particularly, in the stage mechanism shown in FIG.
In order to keep the center of the beam 6 in order to minimize the amount of deflection of the beam 6, in the configuration shown in FIG. 4, since the moving body 14 uses the four surfaces of the beam 6 as guides, the beam 6 is supported by the support body. Etc. cannot be contacted. Furthermore, since the beam 6 itself moves in the rail direction, it is necessary to move the support so as to follow the movement of the beam 6.

An object of the present invention is to provide a stage mechanism which can easily prevent the deflection of the beam.

[0009]

According to the present invention, a beam that is located above a base at a predetermined interval and extends in a predetermined direction, and a movement that moves along the beam using the beam as a guide. A moving body, and at least three moving body static pressure air bearing pads abutting on the base at a position projecting to the outside of the beam are disposed on the moving body, and the beam is provided with the base. interposed between the
Static pressure air bearing pad for one of the beam is attached,
The hydrostatic air bearing pad for the beam has the predetermined
Direction of the beam and the center of the beam
A stage mechanism characterized by being attached to a section is obtained.

[0010]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described below with reference to the drawings.

First, referring to FIG. 1, in FIG. 1, the same components as those in FIG. 4 are designated by the same reference numerals.
Two rails 2 and 3 are arranged on the base 1 at a predetermined interval, and moving bodies 4 and 5 are arranged on the rails 2 and 3, respectively. Here, focusing on the rail 2 and the moving body 4, as shown in FIG. 1B, the moving body 4 is provided with a hydrostatic air bearing pad 12, and between the rail 2 and the moving body 4. Is the static pressure air bearing pad 12
Is intervening. The movable body 4 is guided in the X-axis direction shown in FIG. 1A by the static pressure air bearing pad 12. Further, as shown in FIG. 1B, the moving body 4 is provided with a static pressure air bearing pad 13,
1 is a hydrostatic air bearing pad guided by the base 1 in the Z-axis direction (upward in FIG. 1B).
It moves along the Y-axis direction shown in (a), that is, along the rail 2.

Similarly, the moving body 5 is also provided with static pressure air bearing pads 12 and 13, and the moving body 5 is movable along the rail 3.

The beam 6 includes a moving body 4 and a rigid body (for example,
The beam 6 is connected to the moving body 5 by a leaf spring structure.

A moving body 14 is arranged on the beam 6,
The moving body 14 uses the beam 6 as a guide and moves along the X-axis in FIG.
Move in the axial direction. As shown in FIG. 1B, the base 1
The static pressure air bearing pads 14a to 14c are disposed between the movable body 14 and the movable body 14. That is, the static pressure air bearing pads 14a to 14c are attached to the moving body 14, and the moving body 14 has the static pressure air bearing pads 14a to 1c.
4c guides the base 1 in the Z-axis direction and moves in the X-axis direction.

As shown in FIG. 1A, the moving body 14 is disposed on the beam 6 so as to straddle the beam 6, and the moving body 14 has a base 1 perpendicular to the beam 6. A pair of flange portions 141 extending in parallel with is formed. That is, the movable body 14 is formed with the flange portion 141 extending in the Y-axis direction, and the flange portion 141 is located outside the beam 6. The static pressure air bearing pads 14a to 14c are attached to the flange portion 141 (in the example shown in FIG. 1A, the static pressure air bearing pads 14a and 14b are attached to the flange portion 141 located on the lower side in the figure). Is attached, and the static pressure air bearing pad 14c is attached to the flange portion 141 located on the upper side in the drawing.

At the central portion of the beam 6, a static pressure air bearing pad 15 is attached to the lower surface thereof, and the static pressure air bearing pad 15 is in contact with the base 1. The beam 6 is supported by the hydrostatic air bearing pad 15. That is, the static pressure air bearing pad 15 is
The moving body 14 follows the beam 6 over the entire strokes in the X-axis direction and the Y-axis direction without obstructing the movement of the moving body 14, and bears the weight of the beam 6 by itself. The beam 6 is held so as not to apply an excessive load.

Another example of the stage mechanism according to the present invention will be described with reference to FIG. In FIG. 2, the same components as those in FIG. 1 are designated by the same reference numerals and the description thereof will be omitted.

In the illustrated example, only the rail 2 is arranged on the base 1, and the moving body 4 is arranged on the rail 2. As described above, one end portion of the beam 6 is rigidly fixed to the moving body 4, and the moving body 4 is provided with the hydrostatic air bearing pad 12, so that between the rail 2 and the moving body 4. Has a hydrostatic air bearing pad 12. The movable body 4 is guided in the X-axis direction by the static pressure air bearing pads 12. Further, the moving body 4 is provided with a static pressure air bearing pad 13, and the moving body 4 is guided by the base 1 in the Z axis direction by the static pressure air bearing pad, and moves along the Y axis direction, that is, along the rail 2. To move.

An arm member 17 extending in the Y-axis direction is attached to the other end of the beam 6. The static pressure air bearing pad 1 is provided on the lower surface of the arm member 17 at a predetermined interval in the Y-axis direction.
7a and 17b are attached, and the arm member 17 is
It is in contact with the base 1 via the hydrostatic air bearing pads 17a and 17b.

At the central portion of the beam 6, static pressure air bearing pads 18a and 18b may be attached to the lower surface of the beam 6 at a predetermined interval in the width direction of the beam 6 (Y axis direction). 18 a and 18 b are in contact with the base 1. The beam 6 is supported by the hydrostatic air bearing pads 18a and 18b. That is, the static pressure air bearing pads 18a and 18b
Supports the beam 6 over the entire strokes in the X-axis direction and the Y-axis direction and bears the weight of the beam 6 without hindering the movement of the moving body 14. By attaching the pair of hydrostatic air bearing pads 18a and 18b to the beam 6, it is possible to prevent the beam 6 from rotating about the X axis, that is, twisting.

Also, a pair of static pressure air bearing pads 18a.
It is possible to prevent the deflection of the beam 6 by mounting the electrodes 18 and 18b at a predetermined interval in the X-axis direction.

[0022]

As described above, according to the present invention, the hydrostatic air bearing pad is arranged in the central portion of the beam so that the central portion of the beam supports the beam with respect to the base. That is, there is an effect that bending and twisting of the beam can be easily prevented, and the moving body can be moved smoothly.

Furthermore, since there is no need to worry about the deflection of the beam, the time required for assembly and adjustment can be reduced, and the cost can be reduced.

[Brief description of drawings]

1A and 1B are diagrams showing an example of a stage mechanism according to the present invention, in which FIG. 1A is a plan view and FIG. 1B is a sectional view.

2A and 2B are views showing another example of the stage mechanism according to the present invention, in which FIG. 2A is a plan view, FIG. 2B is a sectional view, and FIG. 2C is a sectional view taken along the line AA of FIG.

FIG. 3 is a diagram showing an example of a conventional stage mechanism.

FIG. 4 is a diagram showing another example of a conventional stage mechanism.

[Explanation of symbols]

1 base A few rails 4,5,14 mobile 6 beams 8 leaf spring 12, 13, 15 Hydrostatic air bearing pad

Claims (3)

(57) [Claims] 1. A moving body that has a beam that is located above a base at a predetermined interval and extends in a predetermined direction, and a moving body that moves along the beam using the beam as a guide. is at least three mobile object static pressure air bearing pads disposed at the position projecting outwardly abutting on the base of the beam, the said beam one beam interposed between the base A hydrostatic air bearing pad is installed to attach the hydrostatic air bearing pad for the beam.
Is in the predetermined direction and in the direction orthogonal to it.
A stage mechanism characterized in that the stage mechanism is attached to a central portion of the beam . 2. A stage mechanism according to claim 1, wherein the stage mechanism is disposed on the base at a predetermined interval.
First and second extending in an orthogonal direction orthogonal to a predetermined direction
And a second rail are provided, and the first and second rails are provided.
Along the first and second rails, respectively.
The first and second moving bodies that move by
A stage mechanism, wherein the beam is connected to the first and second moving bodies . 3. The stage mechanism according to claim 1 , wherein the base is orthogonal to the predetermined direction on the base.
Rails that extend in the orthogonal direction are
Has a moving body that moves along the rail,
One end of the beam is fixed to the moving body and
An arm portion extending in the rail direction is fixed to the end,
The arm is connected to the base via a static pressure air bearing pad for the arm.
Contacting the center of the beam in the orthogonal direction.
A pair of hydrostatic air bearing pads for the beams with a certain spacing.
A stage mechanism characterized in that the stage is arranged .