JPH01188242A - Shift guiding device - Google Patents

Abstract

PURPOSE:To permit the transfer with high precision by connecting the stator or rotor of a linear with the first or second shift body through a spacer and a heat insulating member. CONSTITUTION:A Y-stage 10 is floated up from a surface plate 15 by feeding air into a static pressure pneumatic bearing 12, and shifted in the Y-direction along the fixed guides 16a and 16b by two linear motors 100. An X-stage 14 is floated up from the surface plate 15 similarly in case of the Y-stage 10, by feeding air into static pressure pneumatic bearings 13 and 14, and shifted in the X-direction by a linear motor 200, using the side surface of the Y-stage 10 as a guide. When the X-stage 11 and Y-stage 10 are shifted, a joule's heat is generated by the electric current which flows in the coil (e.g., coil 5) of the linear motor, and each temperature of the movable elements 4a and 4b and stators 2a and 2b is raised by the Joule's heat. However, since the heat transmission to the contiguous X-stage 11, Y-stage 10, and the surface plate 15 is prevented by the insulating members 7 and 9, the temperature rise of these members can be effectively prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a movement guide device, particularly in semiconductor manufacturing equipment, precision machine tools, etc., in which a linear motor is used as a driving means for a moving body such as an The present invention relates to a movement guide device that can be used to position a predetermined position at high speed and with high precision.

<Prior Art> Various types of movement guide devices have been proposed in the past, in which a moving body is moved along a predetermined guide by a driving means such as a linear motor, and is positioned at a predetermined position with a high degree of rust.

FIG. 4 is a perspective view of a main part of a multipolar linear motor used as a driving means in a conventional movement guide device.

The linear motor in the figure has a permanent magnet (
field magnet) 41A and yoke 42A, and permanent magnets 41B, 41C and yokes 42B, 42C on the other side.
are arranged facing each other with a non-magnetic spacer 43 interposed therebetween. The coil 45 wound around the coil pobbin 44 is configured to move through the space therebetween.

The position and speed of coil 45 is limited by the current and frequency supplied to coil 45.

Generally, a moving guide device is constructed by fixing a moving body to a coil pobbin 44 and directly fixing a yoke 42A to a surface plate serving as a base. When current is passed through the coil 45, Joule heat is generated, and the coil pobin 44 and the permanent magnet 41
A, 41B, 41C and yokes 42A, 42B, 42
The temperature of C etc. is rising.

For this reason, coil pobbin 44 and yoke 42A.

The temperature of the movable body and surface plate fastened to 42B, 42C, etc. increases.

When the temperature of the moving body and the surface plate increases, their shapes are bent and deformed, and as a result, the moving particle size of the moving body is reduced. For example, if a temperature difference of 0.5'c occurs between the front and back surfaces of a surface plate with a thickness of 40 mm, a tilt error of approximately 3.6 milliradians will occur in a moving body having a movement range of 250 mm.

Japanese Patent Application Laid-Open No. 62-4538 proposes a movement guide device that prevents a reduction in the particle size of a moving body due to heat generation of a linear motor, but the heat transfer path is not necessarily sufficient.

(Problems to be Solved by the Invention) The present invention effectively insulates the heat generated from the linear motor when moving a moving object using a linear motor as a driving means, and transfers the heat to the moving object and surface plate. The purpose of the present invention is to provide a movement guide device that enables highly accurate movement.

(Means for solving the problem) Two fixed guides are arranged in parallel on a surface plate, and the first movable body is guided in the lateral direction by the two fixed guides provided on the surface plate, and also in the vertical direction. is supported to move parallel to the fixed guide by being guided by the surface plate, and the second
The first movable body is guided in the lateral direction by the first movable body and vertically guided by the surface plate.
Supporting the moving object so that it moves in a direction perpendicular to the moving direction of the moving object,
A first linear motor for driving the first movable body is provided outside the fixed guide, and a second linear motor for driving the second movable body is provided between the first movable body and the second movable body. In addition, the first or second moving body, which is a movable element or a stator of the linear motor, is connected via a spacer and a heat insulating material.

(Embodiment) Fig. 1 is a perspective view of essential parts of an embodiment of the present invention, and Fig. 2 is a perspective view of the main part of an embodiment of the present invention.
It is an AA' cross-sectional view of the figure. 15 on the right side of the figure is a surface plate whose upper surface serves as a smooth reference surface. 10 is a Y stage as a first moving body that moves in the Y-axis direction on the surface plate 15; 11 is an X stage that is a second moving body that moves in the X-axis direction using the Y stage 10 as a guide; 16a, 16;
b are fixed guides 12a and 12b each fixed on the surface plate 15 and for guiding the Y stage 10 in the Y-axis direction;
, 13a, 13b, 13c, and 14a, 14b are porous hydrostatic air bearings, respectively.
Of these, 14a.

14b is the X stage 11 (J) for the Y stage 10
Regulating the position in the Y-axis direction, 13a, 13b.

13c acts to regulate the vertical position of the X stage 11 with respect to the surface plate 15, and 12a and 12b act to regulate the vertical position of the Y stage 10 with respect to the surface plate 15. Further, the position of the Y stage 10 in the xIIIh direction is regulated by a static air bearing (not shown) provided between the Y stage 10 and the fixed guides 16a, 16b.

100 is a part of the linear motor for Y stage 10,
200 is a part of the linear motor for the X stage 11, and both are moving coil type linear motors.

The stator 2a of the linear motor for the Y stage 10 is fixed to the surface plate 15 by a spacer 8 made of plastic such as polycarbonate, which has a lower thermal conductivity than iron or the like. A gap formed between the stator 2a and the surface plate 15 by the spacer 8 is filled with a heat insulating material 9 made of an organic material such as styrofoam across the illuminated surface.

Furthermore, the stator 2b of the linear motor for the X stage 11 is a similar plastic spacer 8a.

8b, it is fixed inside the concave portion of the Y stage 10. The gap formed between the stator 2b and the inner wall of the recess of the Y stage 10 is covered with heat insulating materials 9a, 9b such as styrene foam over the entire surface thereof.

9c is filled.

A movable element (coil bobbin) 4a of a linear motor for the Y stage 10 is connected to the Y stage 10 by a similar spacer 6 made of a plastic material such as polycarbonate. A gap formed between the movable element 4a and the Y stage 10 by the spacer 6 is filled with a heat insulating material 7 such as styrene foam. Similarly, the mover 4b of the linear motor for the X stage 11 has a spacer 6a made of plastic material,
It is connected to the X stage 11 by 6b. This X
When installing the spacer of the stage 11, the entire area facing the Y stage 10 is covered with styrofoam heat insulating material 7a, 7.
b, 7c are provided so as to be located between the movable element 4b and the X stage 11. Incidentally, reference numeral 5 in FIG. 2 is a coil.

As shown in FIG. 1, in this embodiment, Y stage 1
0 is made to float above the surface plate 15 by supplying air to a static pressure air bearing 12, and is moved in the Y direction along fixed guides 16a and 16b by two linear motors 100.

In addition, the X stage 11 is raised above the surface plate 15 in the same way as the Y stage 10 by supplying air to static pressure air bearings 13 and 14, and is moved in the X direction by a linear motor 200 using the side surface of the Y stage 10 as a guide. There is. At this time, X
The stage 11 and the Y stage 10 are adjusted to always have a constant posture by a plurality of preload magnet units (not shown). When moving the X stage 11 and Y stage 10, the coil of the linear motor (for example, coil 5)
Joule heat is generated by the current flowing through the movable elements 4a, 4b and the stator 2a.

The temperature of 2b increases.

In this embodiment, the heat insulating materials 7 and 9 prevent heat from being transferred to the adjacent X stage, Y stage, and surface plate, thereby effectively preventing the temperature of these members from rising.

In addition, in this embodiment, the linear motor is firmly connected to the X stage and the Y stage by using a relatively hard spacer to prevent inappropriate vibrations that occur when the linear motor is weakly connected. The Y stage is moved to a high degree.

In addition, in this embodiment, both the X stage and Y stage are guided in the vertical direction from a surface plate, so that even if the X stage or Y stage moves, no moving load is generated on the other stage, so that the stage remains stationary. Maintains good posture.

FIG. 3 is a schematic diagram of main parts of another embodiment of the present invention when a moving magnet type linear motor is used. Elements on the right side of the figure that are the same as those shown in FIG. 2 are given the same reference numerals.

In this embodiment, the Y stage 10 as the first moving body
vertical hydrostatic air bearing 12a.

It is supported by 12b. Further, it is supported by vertical static pressure air bearings 13a and 13b of the X stage 11 as a second moving body, and supported by horizontal static pressure air bearings 14a and 14b. 18a, 18b are two sets of permanent magnets, 17a, 17
b are two sets of yokes, these are spacers 21a, 2
The coils 20a and 20b on the stator side and the coil bobbin 19 are arranged opposite to each other with 1b interposed therebetween.

Yokes 17a, 17b which are movers, permanent magnet 18a,
The yoke 17a on one side of the yoke 18b and the spacers 21a and 21b is connected to the X stage 11 via the spacers 6a and 6b, and moves linearly together with the X stage 11.

On the other hand, the stator side coils 20a and 20b and the coil bobbin 19 are fixed to the Y stage 10.

The heat insulating materials 7a, 7b, and 7c are filled between the yoke 17a, which is a movable element, and the X stage 11, and the insulating material 9a is arranged on the Y stage 10 so as to surround the moving range of the movable element.

As the X stage 11 moves, the coil 20a.

Joule heat is generated by the current flowing through 20b, and the temperature of the mover such as yoke 17a and the stator such as coil bobbin 19 rises.

Therefore, in this embodiment, the heat insulating materials 7a, 7b, and 7c
Heat transfer to the stage 11 is prevented, and the heat insulating material 9a prevents heat transfer to the Y stage 1o. This results in
This prevents the temperature of the stage, Y stage, and surface plate from rising, and prevents the movement accuracy of the X stage and Y stage from deteriorating due to thermal deformation.

(Effects of the Invention) According to the present invention, by surrounding the coils of the linear motor with a heat insulating material as described above, the heat generated from the coils is
To achieve a movement guide device capable of highly accurate movement, which can effectively prevent heat transfer to a stage, a Y stage, and a surface plate, and prevent deterioration of stage movement accuracy due to thermal deformation. Can be done.

In addition, the thrust of the linear motor is transmitted using a hard spacer made of plastic such as polycarbonate, which can provide sufficient mechanical strength.As a heat insulating material, Styrofoam and other materials have a high heat insulating effect but have the disadvantage of being soft. It is also possible to use insulation materials with

[Brief explanation of the drawing]

FIG. 1 is a perspective view of essential parts of an embodiment of the present invention, and FIG.
FIG. 3 is a schematic view of another embodiment of the present invention, and FIG. 4 is a perspective view of essential parts of a conventional multipolar linear motor. In the figure, 15 is a surface plate, 10 is a Y stage, 11 is an X stage, 16a, 16b are fixed guides, 12, 13, 14 are static pressure air bearings, 100.200 is a linear motor, 2a
, 2b is a stator, 6.8°21 is a spacer, 7.9 is a heat insulator, 4a and 4b are movers, 5.20 is a coil, 17 is a yoke, and 19 is a coil bobbin. % 1 ■

Claims (2)

[Claims] (1) Two fixed guides are arranged in parallel on a surface plate, and the first moving body is guided laterally by the two fixed guides provided on the surface plate, and vertically guided from the surface plate. The second movable body is supported so as to move parallel to the fixed guide, and the second movable body is guided in the lateral direction by the first movable body and guided in the vertical direction by the surface plate. A first linear motor that is supported to move in a direction perpendicular to the moving direction of the movable body and that drives the first movable body is provided outside the fixed guide, and a second linear motor that drives the second movable body. A motor is provided between the first moving body and the second moving body, and a mover or a stator of the linear motor is connected to the first or second moving body via a spacer and a heat insulating material. A moving guide device characterized by: (2) The movement guide device according to claim 1, wherein the heat insulating material is a foamable organic material and the spacer is a plastic material.