JPS59145527A - Conveying device - Google Patents

Abstract

PURPOSE:To improve the characteristics of yawing or pitching or both of a parallel conveying table due to the oscillation of a rotating shaft by a method wherein a set or sets of parallel plate-springs are used for coupling of a conveying system, with which a rotary movement will be converted into a linear one, and a parallel moving table. CONSTITUTION:The lower surface of a parallel moving table 11 is supported in a freely movable manner by a guide 12 through the intermediary of a lubrication layer. Also, a ball nut or a feed nut 15 is screw-fitted to a ball screw or a feed screw 16. Plate springs 18 constitute parallel plate springs. The length, plate thickness, plate width, number of sheets of these plate springs are to be determined in such a manner that there will be no buckling even when the load, including the conveying table 11 and the device placed thereon, is vertically applied. When the ball screw or the feed screw 16 is rotated, a nut 15 moves in horizontal direction by the help of a screw, and the shifting table 11 is shifted by the traction or pressure of the plate spring 18. At that time, the pitching generated when a rotating movement is converted into a linear movement is absorbed by the parallel plate spring 18.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a precision transport device for loading and moving a sample or another device. This device is an X-Y device used in semiconductor manufacturing equipment, such as reduction projection exposure equipment.
Suitable for stage use.

Conventionally, high-precision transfer stages have been used not only in the field of semiconductor manufacturing equipment, but also in the field of measurement equipment or as positioning devices, and there is a strong demand for higher precision in the field of semiconductor manufacturing equipment in particular.

One of the conventionally used devices is shown in the vertical sectional view of FIG. 1 and the combined sectional view of FIG. 2. In this structure, the lower surface of the movable table 1 is supported by a guide rail 2 having a lubricated upper surface, while a rack 6 extending in the moving direction is fixed at the center of the lower surface of the movable table 1. Further, a shaft bearing hole is provided in one wall of the guide 2, and a pinion 4 is fixed to one end of the rotating shaft R passing through this hole and meshed with the rack 6. A handle (not shown) is attached to the other end of the rotating shaft R for manual rotation, or it is coupled to an electric motor for power rotation. A housing for accommodating a nut is fixedly installed, a ball screw or a feeder screw to be screwed into the nut is received by a bearing, and the bearing is fixed to the base G by a nozzle 7.

The ball screw or feed screw 6 is integrated with or connected to the same rotating shaft as described above.

By rotating the rotating shaft with these devices, the moving table 1
moves in a straight line c4, but when converting rotational motion into linear motion, yawing and pitching occur due to the influence of the whirling of the rotating body, resulting in deterioration of the dynamic characteristics of the parallel moving table.

And as a method to eliminate this kind of drawback, the hyper-movement direction of the parallel movement table and the feeding direction of the feeder are
This had the disadvantage of being extremely expensive.

An object of the present invention is to provide a device with good dynamic characteristics.

In order to achieve this object, in the embodiment described later, the moving table and the feeding means are coupled by parallel plate springs.

; L lower lower surface Therefore, the present invention will be described in detail. FIG. 5 shows the form of a longitudinal section, and FIG. 6 shows the form of an A-A cross section. Reference numeral 11 represents a parallel movement table, 12 represents a guide, and the lower surface of the parallel movement table 11 is connected to the guide 12 through a lubricating layer. It is movably supported by. Also, 15 is a pole nut or feed nut, which screws into a 160 ball screw or feed screw. A bearing housing 17 accommodates a bearing that holds the end of the ball screw or feed screw 16, and is itself fixed to the base G.

Next, 18 is a leaf spring, and both constitute a parallel leaf spring. These leaf springs, the width of the movable table 11, and the number of leaf springs to be installed in parallel are determined.In particular, in order to increase torsional rigidity, it is preferable to make the leaf springs sufficiently wide compared to the plate thickness.

Note that the shape of the spring can be modified in various ways.

Reference numeral 19 designates a first fixture for holding each leaf spring 1B in a substantially parallel state and for fixing them to the lower surface of the translation table 11.

Reference numeral 20 denotes a second fixture for gripping the other end of each leaf spring 18 and for fixing these to the side of the nut 15. Note that one end of the ball screw or feed screw 16 is connected to or integrated with a rotating shaft that is rotationally driven manually or by an electric motor.

With the above configuration, when the ball screw or the feed screw 16 is rotated, the nut 15 is fed by the screw and moves in the water direction, and the translation table 11 is moved by being pulled or pressed by the leaf spring 18. At this time, the pitching that occurs when rotational motion is transformed into linear motion is absorbed by the parallel plate springs 18.

The above examples are examples in which pitching and anti-corrosion characteristics were improved, but the following example is an example in which yawing characteristics were improved.

FIG. 8 shows a BB cross section of FIG. 7, and FIG. 9 shows a more detailed perspective view. Further, the same numbers as those on the upper side indicate members having substantially the same function.

Furthermore, 15' is a pole nut or a feed nut, which is provided with parallel plate spring mounting portions on both sides. Reference numeral 18 designates leaf springs similar to those described above, and two parallel leaf springs each constitute a parallel leaf spring.

Each parallel leaf spring includes a respective spacer: it is fixed to the side surface of the nut 15' with a fixture 22.

Next, 21 is a saddle-shaped member, which is provided with a notch 21a that straddles the ball screw or feed screw 16, and is fixed to the lower surface of the parallel movement table 11, while each parallel leaf spring extends in a plane perpendicular to the horizontal plane. Fixed on both sides.

With the above configuration, when the ball screw or feed screw 16 is rotated, the translation table 11 is pushed or pulled by both parallel leaf springs j8 and j8 and moves back and forth.

In this case, the yawing is absorbed by the parallel plate blades. Incidentally, one leaf spring may be provided on each side of the nut 15', and the two may constitute a parallel leaf spring.

The sixth embodiment shown in FIG. 10 is an example in which both pitching and yawing characteristics are improved. In the figure, the upper side and the actual amount -
The same numbers were given to the talented parts.

Furthermore, 24 is a medium-long block with weekdays on the top, bottom, left and right sides. Reference numeral 25 denotes a parallel leaf spring mounting block, which has a circular opening in the center through which a ball screw or feed screw 16 can freely pass, while this block is fixed to the lower surface of the translation table 11.

One end of parallel plate springs 18, 18 extending in a horizontal plane and sandwiching the feed screw 16 from the vertical force is attached to the mounting block 2.
The other end is fixed to the upper and lower surfaces of the relay block 24 as described above.

In addition, a parallel plate spring 18 extends in a plane perpendicular to the horizontal plane and pinches the feed screw 16 from the left and right sides.One end of the 18 is connected to a nut 15'.
The other end is fixed to the left and right surfaces of the relay block 24.

The action of these composite parallel plate springs is that the horizontal component of the whirling of the rotation center of the ball screw or feed screw is absorbed by the left and right parallel plate springs, the vertical component is absorbed by the upper and lower parallel plate springs, and the axial direction component is absorbed by the upper and lower parallel plate springs. This is to transmit only the sending force to the translation table.

Although the above example shows a one-way moving table, if these tables are stacked in two layers and the directions of the feed screws are perpendicular to each other, an X-Y moving table can be obtained.

As explained above, by using one or more sets of parallel plate springs to connect the feed system that converts rotational motion into linear motion and the table for parallel movement, the table for parallel movement caused by the wobbling of the rotation axis 9 The yawing and/or pitching characteristics of the vehicle can be improved, or the rolling characteristics can also be improved. In the past, the parallelism between the translation table and the rotation axis had to be kept at a high level of accuracy, but by using parallel plate springs, this parallelism can be loosened and the tolerance for component accuracy has increased. , it became possible to reduce processing costs and assembly costs.

[Brief explanation of the drawing]

Figure 1 is a longitudinal cross-sectional view of the conventional example, Figure 2 is a cross-sectional view, and Figure 6 is a cross-sectional view of the conventional example.
Fig. 4 is a longitudinal sectional view of another conventional example, Fig. 4 is a 4jtt sectional view. Fig. 5 is a longitudinal sectional view of the (1) embodiment of the present invention, and Fig. 6 is an A-Ai prayer view. Figure 7 is a longitudinal cross-sectional view of the second embodiment.
Figure 8 is a B-Jl snow surface map, and Figure 9 is a perspective view. Figure 10-
is a perspective view of the sixth embodiment. In the figure, 11 is a translation table, 12 is a guide, 15 and 15' are nuts, 16 is a ball screw or feed screw, and 17
18 is a bearing housing, 18 is a plate spring, 21 is a rod-shaped member, 22 is a fixture, 24 is a relay block, and 25 is a mounting block. Applicant Canon Co., Ltd. 1J Tozuharu

Claims (1)

[Claims] (1) A movable table, a support device for movably supporting the movable table, a feeding means for providing a transfer force for moving the movable table, and a means for coupling the movable table and the feeding means. , a transfer device comprising coupling means having parallel leaf springs. (2) The transfer device according to claim 1, wherein the parallel leaf spring extends in a horizontal plane. (6) The transfer device according to claim 1, wherein the parallel plate springs extend in a plane perpendicular to a horizontal plane. (4) The transfer device according to claim 1, wherein the parallel leaf springs extend in planes perpendicular to each other. (5) The transfer device according to claim 1, wherein the feeding means has a structure that converts rotational motion into linear motion.