KR100483954B1 - 3-axis stage driving device used linear actuator with solenoid and permanent magnet - Google Patents

Abstract

According to the present invention, linear actuators are arranged symmetrically in a magnetic flux flow made by a permanent magnet, and a linear driver for supplying a changed current to these coils to perform linear driving by a difference in density of magnetic flux is arranged at a circumferential interval on the stage fixing plate. The dog is arranged to control the three axes of z-Rx-Ry to operate the position of the three-axis drive plate, eliminating the need for a separate amplifier can be produced simply. And, the three-axis stage is made symmetrically, there is an advantage that the simple configuration.

Description

3-axis stage driving device used linear actuator with solenoid and permanent magnet}

The present invention relates to a three-axis stage drive device that can implement a three-axis position movement using a solenoid and a permanent magnet.

In general, the Z-Rx-Ry three-axis stage drive can be used for driving systems that require large forces, ultra-precision drive systems that require small forces, or both.

As an example of the conventional three-axis stage driving device, when the piezoelectric element is used, it has sufficient force for movement. However, when the piezoelectric element is about to move about ± 0.1 mm to 10 nm, the piezoelectric element may be moved due to the limitation of the driving distance and driving voltage. A three-axis system must be constructed that uses an amplifier to extend the drive range. The use of these amplifiers, however, complicates the three-axis system.

In another example, active solenoid movement was not possible with solenoid actuators. That is, only one direction of movement is active, and the other movement is configured to return to the reference plane using a spring. In addition, rotational movement of the drive unit may occur due to a problem of the guide system.

Therefore, there is a need for a three-axis stage apparatus that can overcome the two cases above. As a result, it is necessary to have a three-axis stage device having a long movement section and allowing bi-directional movement of + and-relative to the reference plane. Examples of use thereof include three-axis stage apparatus and ultra-precision three-axis stage apparatus required in lithography equipment.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a three-axis stage driving device having a long operating period and a simple configuration without the need for a separate amplifier by using a permanent magnet in addition to the solenoid.

According to the present invention for achieving the above object, as an apparatus for driving a three-axis position by using the intensity of the magnetic flux is changed in a constant flux flow,

A three-axis stage fixing plate 11;

A three-axis movement drive plate 12 disposed above the three-axis stage fixing plate 11;

Three linear drivers 20A, 20B, and 20C are disposed one-to-one on a triangular vertex in a plane between the three-axis stage fixing plate 11 and the three-axis driving plate 12, and the linear drivers 20A, 20B, 20C),

Upper yoke 25;

A lower yoke 31 disposed below the upper yoke 25;

An actuating shaft 22 installed at the center of the upper yoke 25 and the lower yoke 31 so as to be slidably movable to transmit a movement direction to the triaxial driving plate 12;

An inner yoke 27 and an outer yoke 30 disposed on the circumference of the operating shaft 22 at a predetermined interval between the upper yoke 25 and the lower yoke 31;

The upper coil is inserted between the inner yoke 27 and the outer yoke 30, and at the same time, spaced apart from the upper yoke 25 and the lower yoke 31, respectively, and is disposed above and below to receive current. 28a and lower coil 28b;

A permanent magnet (29) disposed between the upper coil (28a) and the lower coil (28b);

A guide support plate 23 or 33 which is supported on at least one of the upper yoke 25 or the lower yoke 31 to support the operating shaft 22 and simultaneously guide the movement of the operating shaft 22. It is characterized by.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 shows a perspective view of a three-axis stage drive apparatus 10 according to the present invention.

In FIG. 1, reference numeral 11 is a three-axis stage fixing plate, and 12 is a three-axis driving plate.

Three linear drivers 20A, 20B, and 20C are disposed between the stage fixing plate 11 and the three-axis driving plate 12 to correspond to the three vertices as shown in Fig. 2, and these linear drivers ( According to the operation control method of 20A, 20B, and 20C, the three-axis movement drive plate 12 is capable of rotating angles (Rx, Ry) movements for the x and y axes and linear movements for the Z axis. Since the linear drivers 20A, 20B, and 20C have the same configuration, any one of the linear drivers will be described first.

An exploded perspective view of the linear driver 20A is shown in FIG. 3, and an assembled cross-sectional view of the linear driver 20A is shown in FIG. 4.

2 and 3, the linear actuator 20A applied to the present invention applies current to the upper coil 28a and the lower coil 28b in a flow of magnetic flux symmetrically formed up and down by the permanent magnet 29. In this way, the working shaft 22 is linearly moved.

That is, by adjusting the intensity of the current flowing through the upper coil 28a and the lower coil 28b, the operation shaft (by the difference between the magnetic flux density generated in the upper coil 28a and the magnetic flux density generated in the lower coil 28b). The movement direction of 24 is determined, and linear movement occurs while preventing rotation of the drive unit together with the guide upper and lower support plates 23 and 33 serving as guides along the direction.

For example, if the density of the lower magnetic flux Φ2 is higher with respect to the upper magnetic flux Φ1, the working shaft 22 is moved downward in FIG.

The upper yoke 25, the lower yoke 31, the inner yoke 27 and the outer yoke 30 are disposed around the permanent magnet 29 so that two magnetic flux flows that do not change symmetrically are formed. In addition, between the inner yoke 27 and the outer yoke 30, an upper coil 28a and a lower coil 28b are formed to form a flow of magnetic fluxes, which are respectively changed on the upper and lower sides of the permanent magnet 29. It is arranged.

At this time, the N pole and the S pole of the permanent magnet 21 is set to the position so that the flux flow in or out in the radial direction.

In addition, the upper yoke 25, the lower yoke 31, the inner yoke 27 and the outer yoke 30 generally have low coercive force and high relative permeability, so as to form a path through which magnetic flux flows. Preference is given to materials alloyed with cobalt, nickel, tungsten, and aluminum.

The upper yoke 25 and the lower yoke 31 are connected by a cylindrical support 26, the cylindrical support 26 of the upper, lower yoke (25, 31) and the inner, outer yoke (27, It is set such that a predetermined operating interval exists between 30). In this case, the material of the cylindrical support 26 may be formed of a material, for example, aluminum, in which magnetic flux cannot flow.

An operating shaft 22 is installed at the center of the inner yoke 27 to transmit linear movements of the inner and outer yokes 27 and 30 to the outside, and the upper end 22a and the lower end of the operating shaft 22 are provided. The upper support plate 23 for guides and the lower support plate 33 for guides are respectively connected to 22b.

The guide upper support plate 23 and the guide lower support plate 33 maintain a movement interval existing between the inner and outer yokes 27 and 30 and the upper and lower yokes 25 and 31, and are functional. In this aspect, the rotation of the driving unit in the direction of the Rz axis is prevented and at the same time the linear movement of the operating shaft 22 is guided.

At this time, the upper and lower support plates (23, 33) for the guide is made of a thin thin plate to have an elastic restoring force to enable tilting.

The upper yoke 25 and the lower yoke 31 are slidably inserted with the operating shaft 22 so as not to interfere with the linear movement of the operating shaft 22.

The upper support plate 23 is mounted between the upper yoke 25 and the upper plate 24 mounted on the upper surface of the upper yoke 25 with the bolt B1, and the lower support plate 33 is attached to the lower yoke ( 31 and the lower plate 32 attached to the bottom of the lower yoke 31 with the bolt B2.

The upper plate 24 and the lower plate 32 may be made of the same material as the yoke 25, 27, 30, 31 or may be made of a light material.

And the connection between the operating shaft 22 and the upper support plate 23 is connected by the upper connecting nut 21 screwed to the upper end 22a of the operating shaft 22, the operating shaft 22 and the lower support plate The connection with (33) is connected by a lower connection nut (32) screwed to the lower end (22b) of the working shaft (22).

Reference numerals 26a and 30a provide a passage through which the coils 28a and 28b can pass through grooves formed in the cylindrical support 26 and the outer yoke 30, respectively.

Three linear drivers 20A configured as described above are provided at three triangular vertices at 120-degree intervals with respect to the z-axis line as shown in the perspective and plan views shown in FIGS. 1 and 2, respectively, and the three linear drivers 20A, 20B, 20C) is installed.

If the z-axis motion is to be induced, the three linear drivers 20A, 20B, and 20C are simultaneously +-or -movement.

In FIG. 2, for the positive (+) motion of Rx, that is, the counterclockwise rotation about the x axis, the operating axis of the linear driver 20B is raised, and the operating axis of the other linear driver 20C is lowered. In this case, the linear driver 20A maintains its own position without movement, and the tilt movement is performed through the thin support plates 23 and 33 in the linear driver 20A.

During the negative (-) movement of Rx, that is, the rotation of the clockwise axis about the x axis is performed by the operation axis of the linear driver 20B descending and the operation axis of the other linear driver 20C rising.

During Ry's (+) movement, i.e., counterclockwise rotation about the y-axis, the operating axis of the linear actuator 20A is operated upwards and at the same time the operating axes of the other linear actuators 20B and 20C are operated downwards. It is done by

During Ry's (-) movement, the clockwise rotation about the y-axis is performed by the operation axis of the linear driver 20A descending while the other linear drivers 20B and 20C move upward.

In this case, the momentum may be measured using a capacitive sensor.

As described above, according to the three-axis stage driving apparatus of the present invention, the symmetrical flow of magnetic flux generated by the permanent magnets and the intensity of the magnetic flux generated by flowing electric current through the solenoid (coil), that is, Driving by using the intensity, the structure of the three-axis stage drive device is simple and easy to manufacture.

In addition, in the case of using a conventional solenoid actuator, only the positive direction was possible in the reference plane. In the present invention, not only does the movement increase in both directions (± Z), but also the movement drive sections in the Rx and Ry directions increase. Therefore, no amplifier is required as in the prior art. And, by using the support plate for the disc-shaped guide serves as a guide, it is possible to suppress unnecessary movement due to the rotation of the drive unit.

1 is a perspective view of a three-axis stage driving apparatus according to an embodiment of the present invention.

2 is a plan view of FIG.

3 is an exploded perspective view of the linear actuator applied to the three-axis stage driving device of FIG.

4 is a cross-sectional view of the linear driver assembly of FIG.

<Explanation of symbols for the main parts of the drawings>

20A, 20B, 20C: Linear actuator 21,34: Connecting nut

22: operating shaft 23: upper support plate for the guide

24: top plate 25: upper yoke

26: support 27: inner yoke

28a, 28b: coil 29: permanent magnet

30: outer yoke 31: lower yoke

32: lower plate 33: lower support plate for the guide

Claims (6)

A device for driving a three-axis position by using the intensity of the magnetic flux is changed in a constant flux flow, A three-axis stage fixing plate 11; A three-axis movement drive plate 12 disposed above the three-axis stage fixing plate 11; A plurality of linear drivers 20A, 20B, and 20C are disposed between the three-axis stage fixing plate 11 and the three-axis driving plate 12 in a one-to-one correspondence with a triangle vertex, and the linear drivers 20A, 20B and 20C. ), Upper yoke 25; A lower yoke 31 disposed below the upper yoke 25; An operating shaft 22 installed in the center of the upper yoke 25 and the lower yoke 31 so as to be slidably movable to transmit a movement direction to the triaxial driving plate 12; An inner yoke 27 and an outer yoke 30 disposed on the circumference of the operating shaft 22 at a predetermined interval between the upper yoke 25 and the lower yoke 31; The upper coil is inserted between the inner yoke 27 and the outer yoke 30, and at the same time, spaced apart from the upper yoke 25 and the lower yoke 31, respectively, and is disposed above and below to receive current. 28a and lower coil 28b; A permanent magnet (29) disposed between the upper coil (28a) and the lower coil (28b); At least one of the upper yoke 25 or the lower yoke 31 to support the operating shaft 22 and simultaneously guide the movement of the operating shaft 22, to eliminate rotation in the Rz direction, and to enable tilting. 3-axis stage driving apparatus using a linear actuator having a solenoid and a permanent magnet, characterized in that it comprises a support upper and lower support plate (23 or 33) for the guide connected. The method of claim 1, Three-axis stage driving apparatus using a linear actuator having a solenoid and a permanent magnet, characterized in that the two magnetic flux flow is formed symmetrically on the upper and lower sides based on the permanent magnet (29). The method of claim 1, 3-axis stage driving using a solenoid and a linear actuator having a permanent magnet, characterized in that the movement direction of ± of the z-axis is determined by controlling the intensity of the current applied to the upper and lower coils 28a and 28b. Device. The method of claim 1, The upper and lower support plates 23 and 33 for the guide have an elastic restoring force to allow the tilting, and serve to prevent rotational movement (Rz) other than z-Rx-Ry movement of the three-axis driving plate (12). 3-axis stage driving device using a linear actuator having a solenoid and a permanent magnet. The method of claim 1, A plurality of linear drivers (20A, 20B, 20C) is a three-axis stage drive device using a linear actuator having a solenoid and a permanent magnet, characterized in that arranged in a 120-degree circumferential angle from the center of the three-axis drive plate (12). The method of claim 1, The actuating shaft 22 of the linear actuators 20A, 20B, and 20C is connected to the three-axis driving plate 12 and the upper connecting nut 21 by using a solenoid and a linear actuator having a permanent magnet. 3-axis stage drive.