JPS6145988A - Vibration-proof structure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of the Invention] The present invention relates to a vibration isolation structure in a mechanical device having a member movable relative to the main body of the mechanical device, such as a positioning stage. The present invention relates to a vibration isolation structure that prevents vibration of the mechanical device body by absorbing the reaction force received by the mechanical device body by moving freely relative to the lower part of the mechanical device body that is in contact with the floor.

[Description of the Prior Art] In recent years, there has been an increasing demand for extremely high-precision positioning devices in various precision measuring devices and various semiconductor-related manufacturing devices. Usually, this type of positioning device is
The device has a stage that moves in the direction, and a main body of the device that supports the stage is supported from the device base via an elastic body. This is to prevent vibrations transmitted from the ground after the stage has stopped.

FIG. 1 shows the configuration of a general high-precision positioning device.

In the figure, 1 is a positioning stage that moves on the main body 2 of the apparatus. Further, 4 is a device base portion, which is fixed to the ground 5.

Further, the device main body 2 is connected to the device base portion 4 by an extremely soft elastic body 3 (such as an air spring) 3 for the purpose of preventing external vibrations. In addition, in order to move stage 1, a device (generally a motor, a feed screw, etc.) that accelerates or decelerates stage 1 relative to device body 2 is required.
is required, but is not shown here.

By the way, in order to move the stage 1 on the device main body 2, it is natural to apply force to the stage 1 and accelerate it.
To stop, apply force in the opposite direction and decelerate to stage 1.
move. At this time, the above-mentioned acceleration and deceleration forces give reaction forces to the device main body 2.

Since the apparatus main body 2 is supported by an extremely soft elastic body 3 against the apparatus base part 4, it begins to move in the opposite direction to the stage 1 due to the above-mentioned reaction force.

After the stage 1 has moved in this way, the device main body 2
This vibration is extremely harmful because it continues even after the stage 1 has stopped.

Conventionally, various methods have been used to prevent such vibrations, and these are listed below.

a) The weight of the apparatus main body 2 is set to be extremely large relative to the stage 1, and the amplitude of the vibration generated by the apparatus main body 2 is reduced.

b) Slow down the movement speed of stage 1.

C) Applying a force from the outside to stop the vibration of the device body 2.

However, all of these countermeasures have some kind of flaw and are subject to certain practical limitations.

That is, in the method a), it is necessary to make the weight of the main body 2 of the apparatus extremely large, and in the method b), the operating speed of the apparatus is reduced, which is not preferable. Further, in the method C), there is a disadvantage that a driving source that generates an extremely large force for stopping the vibration of the apparatus main body 2 must be provided externally.

[Object of the Invention] An object of the present invention is to eliminate all of the above-mentioned defects and to provide a vibration isolation structure that essentially does not generate vibrations in the apparatus body.

[Explanation of Examples] The present invention will be explained in detail below.

FIG. 2 is a schematic diagram of a mechanical device according to an embodiment of the present invention, in which 1 is a stage, 2 is a device main body supporting stage 1, and 6 is a mechanical device on which the device main body 2 slides. 3 is an elastic body supporting the lower part of the apparatus body; 4 is a lower part of the apparatus body 6 via the elastic body 3;
5 is the base of the device that supports the , and 5 is the ground.

Also in this mechanical device, when the stage 1 is moved above the device main body 2, a reaction force from the stage 1 is applied to the device main body 2, as in the above-mentioned conventional example.

In the conventional example, at this time, this reaction force is tried to be suppressed by some force, and this reaction force becomes vibration of the main body 2 of the apparatus.

However, in the mechanical device of the present invention, since the device main body 2 is not fixed to the device main body lower part 6, when the device main body 2 receives a reaction force, it freely slides against the device main body lower part 6. It becomes possible to move. In other words, the reaction force is absorbed by the sliding movement of the device main body 2, and vibrations are not generated in the device main body 2.

In a mechanical device having a positioning stage as described above, by configuring the mechanical device main body to be freely movable relative to the lower part of the mechanical device, it is possible to prevent vibration of the mechanical device main body.

[Application Examples of the Invention] Note that the following applications can also be easily realized with the configuration of the present invention.

a) After the stage has moved a certain stroke, the apparatus main body is repositioned with respect to the lower part of the apparatus main body.

b) Changing the frictional force of the apparatus main body against the lower part of the apparatus main body by changing the speed of the stage or the stage mm.

This change in frictional force can be carried out by controlling the frictional force using, for example, electromagnetic force or vacuum suction force.

Further, the present invention can be applied as a vibration-proof structure for cylinders used in any industrial machinery, i-pistons, etc., such as hydraulic servo cylinders.

[Effects of the Invention] As explained above, according to the present invention, in a mechanical device having a member movable relative to the main body of the mechanical device, a structure is provided in which the main body of the mechanical device can be freely moved relative to the lower part of the mechanical device. By doing so, it is possible to prevent vibration of the main body of the mechanical device.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of a conventional mechanical device having a positioning stage, and FIG. 2 is a schematic diagram of a mechanical device of the present invention having a positioning stage. DESCRIPTION OF SYMBOLS 1...Stage, 2...Device main body, 3...Elastic body, 4...Device base part, 5...Ground, 6...Device main body lower part.

Claims (1)

[Claims] 1. In a vibration isolation structure for a mechanical device having a member that is movable relative to the main body of the mechanical device, the main body of the mechanical device is movable in a direction that alleviates the influence of movement of the movable member. A vibration-proof structure characterized by absorbing a reaction force applied to a main body of a mechanical device when said member moves. 2. The vibration isolation structure according to claim 1, wherein the movable member is a positioning stage. 3. The vibration isolation structure according to claim 1, wherein the movable member is a piston or a cylinder.