JPH0727195A - Plain bearing guide mechanism - Google Patents

Abstract

PURPOSE:To provide the degree of freedom in a direction alpha to provide stable and high straight guide precision with a time by a method wherein the degree of freedom is provided in a direction THETA or direction Y and a block fixed to a table and having a horizontally processed notch thin resilient hinge is coupled to an existing leaf spring-form block. CONSTITUTION:A vertically formed four-spot-notch thin resilient hinge 13 has two spots, making a pair, on each side and are formed in a parallel leaf spring- form state and has the degree of freedom in a direction Y and a direction THETA. The horizontally formed notch thick resilient hinge 13 is provided with the degree of freedom in a direction alpha. By means of the degrees of freedom, a slide surface forms a surface on which forces generated by coil springs 14 and 14' are uniformly distributed and can be brought into slide contact with straight blocks 2 and 2' and stable high straight guide precision with a time is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing of a slide bearing type stage which is stable over time and has a high straight guide accuracy.

[0002]

2. Description of the Related Art In many cases, a shape and size measuring apparatus for electronic devices such as a magnetic head of a semiconductor or a magnetic storage device requires a stage that satisfies a high straight guide accuracy. The conventional slide bearing guide mechanism, which has a high precision of straight guide and has a small and inexpensive slide bearing guide stage, has been used for the above device.
When the contact area between the sliding material and the straight guide reference surface changes with time, the bearing rigidity changes, the load moment balance seen from the stage drive changes, yawing occurs, and the straight guide accuracy decreases. There was a drawback to do. A conventional plain bearing guide mechanism will be described with reference to FIGS. 2, 4 and 5. FIG. 2 is an example of a stage having a conventional slide bearing guide mechanism. FIG. 4 is an enlarged view of the sliding bearing guide mechanism portion of FIG. FIG. 5 is a diagram focusing on the contact surface of the sliding material. Screws 1 and 2 on table 1
Sliding members 16 and 16 'are adhered to both ends of the plate spring-like block 19 attached at 2', and springs 14 and 14 'arranged between the table 1 and the plate spring-like block 19 push the opposite surfaces. The sliding members 16 and 16 'are in sliding contact with the side surfaces of the straight guide block 2'. The leaf spring block 19 has a circular arc notch machined in a vertical direction and a thin elastic hinge 20,
20 'is formed. The circular arc cutout thin elastic hinges 20 and 20 'keep the sliding contact area between the sliding members 16 and 16' and the straight guide block 2'constant, and the springs 14 and 1 '.
The purpose is to keep the load torque constant due to the weight of 4 '. Further, the sliding members 16 and 16 'have a degree of freedom only in the θ direction. For this reason, since it is fixed in the α direction and the y direction, there is no degree of freedom due to a slight change in the pressure distribution on the sliding surface, so the load torque changes and the straight guide accuracy decreases due to yawing. There are drawbacks.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
Since the degree of freedom of the sliding member guide mechanism sliding member is only in the θ direction, there is a drawback in that the straight guide accuracy changes (deteriorates) over time. The present invention eliminates these drawbacks, and provides freedom not only in the θ direction but also in the α direction and the Y direction,
An object of the present invention is to provide a bearing guide mechanism that is stable over time and has high straight guide accuracy.

[0004]

In order to achieve the above object, the present invention forms four vertically cut notch thin elastic hinges in a leaf spring block to which a sliding material is adhered, By having a degree of freedom in the Y and Y directions and connecting a block fixed to the table and having a horizontally thin cutout thin elastic hinge to the existing leaf spring block, the degree of freedom in the α direction is provided. .

[0005]

[Function] The four notched thin elastic hinges formed in the vertical direction form pairs of two parallel springs on each side,
It is possible to have a degree of freedom in the Y direction and the θ direction. Further, the notch thin elastic hinge formed in the horizontal direction has a degree of freedom in the α direction. Due to these degrees of freedom, the sliding surface can always come into sliding contact with the straight block with the force of the spring as a surface having an even pressure distribution, and high straight guiding accuracy that is stable over time can be obtained.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1, 3 and 5. 1 is a table, 2 and 2'is a straight guide block, 3 is a base, 4 is a block for adjusting the height of a ball screw, 5 is a ball screw end bearing holder, 6
Is a ball screw, 7 is a support unit, 8 is a coupling, 9 is a drive motor, 10 is a leaf spring block, 11
a, 11b, 11c and 11d are arc-shaped thin-walled elastic hinges machined in the vertical direction, 12 is a block connecting the table and the leaf spring block of 10, and 13 is a horizontally-machined arc-shaped thin-walled elastic Hinges, 14 and 1
4'is a coil spring, 15, 15 'and 17, 17' are 1
Sliding members attached to the table lower surface of the table, 16 and 1
6'is a sliding member attached to the leaf spring block of 10, and 18 and 18 'are 16 and 1 when viewed from the ball screw.
6'is a slide member attached to the side surface of the table 1 at a position symmetrical to the 6 ', and 21 and 21' are screws connecting the 12 blocks to the table 1. This operation will be described below. The motor 9 is driven by a control device and a motor driver (not shown), and the table 1 is driven through the coupling 8 and the ball screw 6. At this time, the accuracy of the straight guidance in moving the table is determined by the straight guidance block 2
2 ', the table 1, and the sliding member adhered to the plate spring block 10 are highly determined by the sliding bearing portion in sliding contact with each other. Therefore, the present invention focuses on this sliding bearing portion. The coil springs 14 and 14 'are arranged on the back side of the sliding members 16 and 16' in order to apply a preload to the sliding contact portion. The whirling caused by the rotational movement of the ball screw affects the table via the slide bearing portion. As for the whirling motion, when explained in FIG. 5, the rotation θ on the X axis, the motion in the Y axis direction, and the rotation α on the Z axis are large motions. In order to eliminate these movements, that is, to give freedom to movement, a circular arc cut thin elastic hinge 13 machined in a horizontal direction on a block 12 connected to the table 1 by screws 21 and 21 '. And has a degree of freedom with respect to the movement of α. Further, the block 10 connected to the existing block 12 has four arcuate notched thin elastic hinges 11a, 11b, 11c and 11 which are machined in the vertical direction.
d is formed to have a parallel leaf spring shape, and has a degree of freedom with respect to the movement of θ and the movement in the Y direction. Therefore, it is possible to realize a sliding bearing guide mechanism which always has a uniform sliding contact area of pressure distribution and has high straight guide accuracy which is stable over time.

[0007]

According to the present invention, it is possible to realize a sliding bearing guide mechanism which has stable high straight guide accuracy over time and is almost the same price as the conventional machine.

[Brief description of drawings]

FIG. 1 is an overall stage view showing an embodiment of the present invention.

FIG. 2 is an overall view of a stage having a conventional plain bearing mechanism.

FIG. 3 is a diagram of a sliding bearing mechanism showing an embodiment of the present invention.

FIG. 4 is a diagram of a conventional plain bearing mechanism.

FIG. 5 is a diagram showing the movement of a sliding member.

[Explanation of symbols]

 1 table 2, 2'guide block 10 leaf spring block 11a, 11b, 11c, 11d elastic hinge 12 block 13 elastic hinge

Claims (1)

[Claims] 1. A leaf spring block having a notched thin-walled elastic hinge fixed to a moving table and formed in the moving direction, and four vertically formed notched thin-walled elastic hinges connected to the block. A moving table configured to press the both ends of the leaf spring block and a spring arranged between the block and the block; and a sliding member bonded to the leaf spring block; and a straight table of the table. A bearing guide mechanism, wherein a guide block, the block and a sliding member are in sliding contact with each other.