WO2010137320A1 - Alignment stage - Google Patents

Abstract

An alignment stage comprises a base (1) and a top table (4a) which is arranged above the base and holds a work to which a moving load is applied, wherein a support unit (13) and driving units (14A, 14B, 14C, 14D) are provided between the base (1) and the top table (4a) and at portions which are arranged in a zigzag formation with respect to the load movement direction (L) to correspond to the center and four corners of the top table (4a), the support unit (13) being provided with three degrees of freedom of X, Y, and θ, and the driving unit comprising a uniaxial direction ball screw linear motion mechanism (9) in addition to the structure similar to the support unit (13). The ball screw linear motion mechanisms (9) of one diagonally arranged pair of driving units (14A, 14B) are arranged to be orthogonal with the ball screw linear motion mechanisms (9) of the other diagonally arranged pair of driving units (14C, 14D). The moving load applied to the top table (4a) through the work while moving in the load movement direction (L) is successively received by the respective driving units (14A, 14C), the support unit (13), and the respective driving units (14B, 14D), so as to prevent deformation of the top table (4a).

Description

Alignment stage

The present invention relates to an alignment stage, and more particularly, to an alignment stage that has three degrees of freedom of X, Y, and θ and is used to align a workpiece that receives a moving load.
This application claims priority based on Japanese Patent Application No. 2009-126034 for which it applied to Japan on May 26, 2009, and uses the content here.

In recent years, as a method of forming an electrode pattern (conductive pattern) such as a liquid crystal display on a required substrate, a printing technique using a conductive paste as a printing ink instead of fine processing such as etching of a metal vapor deposition film, for example, A method of printing and forming an electrode pattern on a substrate using an intaglio offset printing technique has been proposed (see, for example, Patent Document 1 and Patent Document 2).

When a fine print pattern such as the electrode pattern is offset printed on a flat print target such as the substrate, high printing accuracy is required. Therefore, as an offset printing apparatus in the case of performing offset printing with high printing accuracy, a flat plate printing apparatus using a flat plate similar to the object to be printed is advantageous.

In general, when offset printing is performed using a flat plate and a printing target, a rotated blanket roll is pressed against a pre-inked plate with a required contact pressure and moved relative to the plate. . Thereby, the ink is transferred (received) from the plate to the surface of the blanket roll. Next, with the blanket roll being rotated, the blanket roll is moved relative to the printing object while being pressed against the printing object with a required contact pressure. As a result, the ink is retransferred (printed) from the blanket roll onto the surface to be printed, and the printing pattern of the plate is reproduced on the surface to be printed.

By the way, when the print target is sequentially replaced with a new one and printing is performed, if the position of the installation position is shifted for each print target, there arises a problem that the reproducibility of the print position is lowered.

In addition, the plate gradually wears (consumes) when used for printing. For this reason, it is necessary to exchange for every required number of printings and printing times. In addition, when performing overprinting, it is necessary to exchange plates. When the plate installation position after the replacement is displaced with respect to the plate installation position before the replacement, the reproducibility of the printing position is deteriorated.

High print accuracy required for offset printing of fine print patterns such as electrode patterns when there is a drop in reproducibility of the print position due to misalignment of the print target or plate position as described above May not be satisfied.

In order to avoid the above problems, it is conceivable that the plate used for offset printing and the printing target are held on an alignment stage, and alignment is performed for each plate and each printing target before starting the printing operation. The alignment corrects the misalignment of the installation position of the plate and the printing target, and improves the reproducibility of the position so that the contact position of the plate and the printing target with respect to the blanket roll is the same every time. Thereby, it is considered that the reproducibility of the position of the print pattern to be printed on the printing object from the plate via the blanket roll can be improved.

In order to avoid the above problems, it is possible to further correct the position of the plate or the printing object using an alignment stage. When using an alignment stage, phenomena due to design errors, such as the direction of movement of the outer peripheral surface of the rotating blanket roll (direction perpendicular to the axis of the blanket roll) and the blanket roll pressed against the plate or printing object When there is a tilt or deviation in the relative movement direction when the relative movement is performed, or when there is an eccentricity in the blanket roll and fluctuations occur in the peripheral speed of the blanket roll that rotates at a certain rotational speed. While the blanket roll is brought into contact with the plate or the printing target held on the alignment stage, the plate or the printing target can be moved following the movement of the contact portion on the outer peripheral surface of the blanket roll.

By the way, in the manufacturing process of liquid crystal displays and semiconductors, it is necessary to ensure the overlay accuracy of the members and layers to be laminated. For this purpose, for example, an alignment stage as shown in FIGS. 8 and 9 is used as an alignment stage for arranging the work in the XY orthogonal coordinate plane and aligning the rotation angle θ.

The alignment stage shown in FIGS. 8 and 9 is provided with one support unit 2 and three drive units 3A, 3B, and 3C at the rectangular portion of the base 1 on the fixed side. Further, the rectangular portion of the top table 4 on the moving side is mounted on and attached to the upper side of the support unit 2 and the drive units 3A, 3B, 3C.

In the support unit 2, linear guide rails 6a and 6b and two linear motion guides 5a and 5b composed of guide blocks 7a and 7b slidably attached to the guide rails 6a and 6b are vertically moved in an orthogonal posture. Arranged in two stages. The guide rail 6b of the upper linear motion guide 5b is attached to the upper side of the guide block 7a of the lower linear motion guide 5a. Further, a swivel bearing 8 capable of swiveling in a horizontal plane is attached to the upper side of the guide block 7b of the upper linear motion guide 5b. As a result, three degrees of freedom of X, Y, and θ are obtained at the top of the swivel bearing 8 that is the upper end of the support unit 2 with reference to the guide rail 6a of the lower linear guide 5a that is the lower end of the support unit 2. be able to.

In the support unit 2, the guide rail 6 a of the lower stage linear motion guide 5 a is installed at a corresponding portion of the base 1. A corresponding portion of the top table 4 is attached to the upper side of the slewing bearing 8.

Each drive unit 3A, 3B, 3C has a configuration similar to that of the support unit 2 and is parallel to the guide rail 6a of the lower linear motion guide 5a, a servo motor 10, a screw shaft 11 connected to its output shaft, and a screw shaft A ball screw linear motion mechanism 9 comprising a nut member 12 screwed to 11 is disposed. The nut member 12 of the ball screw linear motion mechanism 9 is connected to the guide block 7a of the lower linear motion guide 5a. As a result, the nut member 12 is moved along the axial direction of the screw shaft 11 by the forward / reverse drive of the screw shaft 11 by the servo motor 10 of the ball screw linear motion mechanism 9. The guide block 7a of the lower linear motion guide 5a can be integrally moved along the longitudinal direction of the guide rail 6a.

In each drive unit 3A, 3B, 3C, a guide rail 6a of the lower linear motion guide 5a and a ball screw linear motion mechanism 9 are provided at corresponding locations on the base 1, respectively. A corresponding portion of the top table 4 is attached to the upper side of the slewing bearing 8. At this time, among the drive units 3A, 3B, 3C, the direction (drive direction) of the ball screw linear motion mechanism 9 of the two drive units 3A, 3B is the X-axis direction, and the ball screw of the remaining one drive unit 3C The direction (drive direction) of the linear motion mechanism 9 is the Y-axis direction, and the drive directions are orthogonal to each other.

According to the above alignment stage, the position and movement of the guide block 7a of the lower linear motion guide 5a by the ball screw linear motion mechanism 9 provided in each of the drive units 3A, 3B and 3C, and the moving direction of the guide block 7a By appropriately adjusting the amount of movement and the amount of movement, the horizontal displacement of the top table 4 in the XY plane and the rotational displacement of the rotation angle θ can be combined. Thereby, it is possible to perform alignment in the X, Y, and θ triaxial directions for a workpiece (not shown) to be aligned held on the top table 4 (see, for example, Non-Patent Document 1).

Japanese Patent No. 2797567 Japanese Patent No. 3904433

THK Corporation, Catalog “Alignment Stage CMX”, August 3, 2007, Catalog Number 238-4

The conventional alignment stage shown in FIGS. 8 and 9 assumes that the workpiece is aligned in an optical process in the manufacturing process of a liquid crystal display or a semiconductor. For this reason, it is not considered much to load a load.

That is, in offset printing using a flat plate or a printing target, alignment is performed by holding the plate or the printing target on the alignment stage shown in FIGS. 8 and 9, and the position of the printing plate or the printing target is corrected to a desired position. I do. Next, the rotated blanket roll is pressed against the plate or the printing target held on the alignment stage with a required contact pressure, and is moved relative to the plate or the printing target. Then, a load is applied to the alignment stage holding the plate and the printing target on an elongated band-like region extending in the axial direction of the blanket roll corresponding to the contact portion between the plate or the printing target and the outer peripheral surface of the blanket roll. To do. The elongated strip-shaped region on which the load is applied moves along the direction of relative movement of the blanket roll with respect to the plate or the printing target as time passes. For this reason, a moving load acts on the alignment stage.

8 and 9, the top table 4 is supported by the support unit 2, the drive units 3A, 3B, and 3C on the squares of the top table 4. For this reason, for example, when a load acting on an elongated region extending along the Y-axis direction acts as a moving load moving in the X-axis direction, the moving load is an intermediate portion of the top table 4 in the X-axis direction, that is, If the support unit 2 and the drive units 3A, 3B and 3C are not supported by any of the intermediate portions in the X-axis direction of the top table 4, the vertical support rigidity of the top table 4 is reduced. Then, there is a possibility that the top table 4 is deformed so as to be bent. Due to this deformation, there is a possibility that a position shift occurs in a work (not shown) such as a plate or a printing target held on the top table 4.

In the alignment stage shown in FIG. 8 and FIG. 9, the horizontal displacement in the XY plane and the rotation angle θ are set on the top table 4 by the three drive units 3A, 3B, 3C having the ball screw linear motion mechanism 9. The three axes of X, Y, and θ are aligned by combining rotation. Here, the number of ball screw linear motion mechanisms 9 of the drive units 3A and 3B for driving in the X-axis direction and the number of ball screw linear motion mechanisms 9 of the drive unit 3C for driving in the Y-axis direction are as follows. Is different. For this reason, a difference occurs in the horizontal rigidity between the X-axis direction and the Y-axis direction. Therefore, for example, when a movement load is applied to the plate or the printing target by bringing the blanket roll into contact with the offset printing, if the position correction of the plate or the printing target is performed by the alignment stage, the alignment stage Due to the difference in horizontal rigidity between the X-axis direction and the Y-axis direction, there is a difference in ease of movement in the X-axis direction and movement in the Y-axis direction. Thereby, there is a possibility that the position correction desired for the plate or the printing target cannot be performed.

In the alignment stage shown in FIGS. 8 and 9, the amount of drive of each ball screw linear motion mechanism 9 is controlled by an encoder built in each servo motor 10 of each ball screw linear motion mechanism 9 of each drive unit 3A, 3B, 3C. To control the position of the top table 4. Here, in each of the following cases, for example, when a moving load is applied to the top table 4, or when the top table 4 is to be displaced horizontally or rotationally while the moving load is applied, the load is applied. When a thrust transmission part such as the screw shaft 11 or the nut member 12 of each ball screw linear motion mechanism 9 acting as an external force is bent or rattled, the error element cannot be eliminated. In addition, the presence of the error element itself cannot be detected. For this reason, there is a possibility that highly accurate position control of the top table 4 cannot be performed.

Furthermore, in the alignment stage shown in FIGS. 8 and 9, each servo motor 10 that is a drive source of each ball screw linear motion mechanism 9 of each drive unit 3A, 3B, 3C is covered on the base 1 by the top table 4. It is arranged at the position to be displayed. For this reason, the top table 4 and the base 1 are thermally deformed due to the heat generated by each servo motor 10, and a position shift occurs in a work (not shown) held on the top table 4 due to the thermal deformation of the top table 4 or the base 1. May occur.

As described above, in the conventional alignment stage shown in FIGS. 8 and 9, the workpiece on which the moving load acts is held in a state where the workpiece is accurately positioned in the three axis directions of X, Y, and θ, It is difficult to correct the position of the workpiece in the three axis directions of X, Y, and θ with high accuracy in a state in which is acting.

The present invention can hold a workpiece to which a moving load is applied in a state where the workpiece is positioned with high accuracy in the three axis directions of X, Y, and θ. Provided is an alignment stage that can be displaced with high accuracy in three axial directions of X, Y, and θ.

According to the first aspect of the present invention, an alignment stage according to the present invention is orthogonal to a base and a top table disposed at a position above the base for holding a work on which a moving load acts. A required number of support units having three degrees of freedom of X, Y, and θ, comprising a guide slidable in a direction, and a swivel bearing provided on the guide, and a uniaxial linear motion mechanism on the support unit At least three drive units, and the support unit and the drive unit are provided between the base and the top table in a staggered arrangement along the moving direction of the moving load. The driving directions of the two driving units by the linear motion mechanism and the driving directions of the remaining driving units by the linear motion mechanism are orthogonal to each other in the XY plane. That.

According to the second aspect of the present invention, the staggered arrangement is a portion corresponding to the square portion and the center of the top table.

According to a third aspect of the present invention, the staggered arrangement is provided at locations corresponding to the square portion and the center of the top table, and drive units are provided at locations corresponding to the square portion of the top table. The support unit is provided at a location corresponding to the center of the top table.

According to the fourth aspect of the present invention, an alignment stage according to the present invention is orthogonal to a base and a top table arranged at a position above the base for holding a work on which a moving load acts. A drive unit having a three-degree-of-freedom of X, Y, and θ and a uniaxial linear motion mechanism, and comprising a guide that is slidable in a direction and a slewing bearing provided on the guide. The unit is provided in a staggered arrangement along the moving direction of the moving load between the base and the top table, and among each of the driving units, a driving direction by a linear motion mechanism of two driving units, The drive directions of the remaining two drive units by the linear motion mechanism are orthogonal to each other in the XY plane.

According to the fifth aspect of the present invention, the staggered arrangement is a portion corresponding to a line connecting the intermediate position of each side of the top table and the center of the top table.

According to a sixth aspect of the present invention, the linear motion mechanism includes a motor, a screw shaft coupled to the output shaft of the motor, and a ball screw linear motion mechanism including a nut member screwed to the screw shaft. The motor is arranged so as to protrude outward from the base.

According to the seventh aspect of the present invention, a linear scale is provided on the base in the vicinity of each drive unit for detecting the drive amount by the linear motion mechanism in the uniaxial direction of each drive unit.

The alignment stage of the present invention exhibits the following excellent effects.

(1) A top table for holding a workpiece to which a moving load acts is placed above the base. A required number of support units having three degrees of freedom of X, Y, and θ consisting of a guide that is slidable in two orthogonal directions between the base and the top table, and a slewing bearing provided on the guide. The support unit includes three or more drive units each including a uniaxial linear motion mechanism. The support unit and the drive unit are arranged in a zigzag pattern along the moving direction of the moving load. Of the above drive units, the drive directions of the two drive units by the linear motion mechanisms are orthogonal to the drive directions of the remaining drive units by the linear motion mechanisms in the XY plane. The alignment stage of the present invention having such a structure combines the horizontal movement of the top table in the XY plane and the rotation of the rotation angle θ by combining the driving of the three or more driving units. Can be moved. Therefore, the position of the work held on the top table can be corrected in the three axis directions of X, Y, and θ.

(2) According to the alignment stage of the present invention, even if a moving load acts on the work held on the top table, the moving load acting on the top table via the work is reduced. It can be continuously received by each drive unit and support unit arranged in a staggered manner along the moving direction. For this reason, it is possible to increase the vertical rigidity of the top table, and to prevent the top table from being deformed by the moving load. Therefore, it is possible to prevent the displacement of the workpiece due to the deformation of the top table.

(3) In the alignment stage according to the present invention, the staggered arrangement along the moving direction of the moving load is made to correspond to the square portion and the center of the top table. Thereby, staggered arrangement | positioning along the moving direction of the moving load of each drive unit and a support unit can be performed easily. Furthermore, the top table can be supported in a balanced manner in the front-rear and left-right directions by the drive units and the support units.

(4) In the alignment stage according to the present invention, the staggered arrangement along the moving direction of the moving load is made to correspond to the square portion and the center of the top table. And a drive unit is provided in the part corresponding to the square part of the said top table, respectively. Further, a support unit is provided at a location corresponding to the center of the top table. The alignment stage of the present invention having such a configuration can obtain the same effect as the above (3). In addition, two drive units equipped with a linear motion mechanism can be arranged in two orthogonal directions so that the horizontal rigidity along the X-axis direction and the horizontal rigidity along the Y-axis direction of the top table are equal. can do. Therefore, when moving the top table and correcting the position of the workpiece while the moving load is applied to the workpiece held on the top table, the movement in the X-axis direction and the movement in the Y-axis direction are performed. The possibility of occurrence of bias can be reduced, and the position correction desired for the workpiece can be performed.

(5) In the alignment stage according to the present invention, a top table for holding a workpiece on which a moving load acts is disposed above the base. Between the base and the top table, it has three degrees of freedom of X, Y, θ consisting of a guide slidable in two orthogonal directions and a swivel bearing provided on it, and a linear motion mechanism in one axial direction A drive unit having a configuration is provided. The drive units are arranged in a staggered pattern along the moving direction of the moving load. Among the above drive units, the drive directions of the two drive units by the linear motion mechanism and the drive directions of the remaining two drive units by the linear motion mechanism are orthogonal to each other in the XY plane. The alignment stage of the present invention having such a configuration can obtain the same effects as the above (1), (2), (3), and (4).

(6) In the alignment stage according to the present invention, the staggered arrangement along the moving direction of the moving load is made to correspond to the line connecting the intermediate position of each side of the top table and the center of the top table. Thereby, each unit can be arranged closer to each other. This is advantageous when applied to an alignment stage having a smaller planar shape.

(7) A linear movement mechanism in one axial direction of each drive unit provided in the alignment stage according to the present invention includes a motor, a screw shaft connected to the output shaft, and a ball having a nut member screwed to the screw shaft. It consists of a screw linear motion mechanism. The motor of each ball screw linear motion mechanism is disposed so as to protrude outward from the base. The alignment stage of the present invention having such a configuration can efficiently dissipate heat generated by each servo motor of each ball screw linear motion mechanism serving as a drive source of each drive unit into the atmosphere. Therefore, it is possible to suppress the thermal deformation of the base and the top table due to the heat generation of each servo motor. For this reason, it is possible to reduce the possibility that the workpiece held by the top table is displaced due to the thermal deformation of the base and the top table.

(8) The alignment stage according to the present invention is provided with a linear scale for detecting the driving amount by the linear motion mechanism in the uniaxial direction of each driving unit on the base in the vicinity of each driving unit. Thereby, the linear motion mechanism in the uniaxial direction of each drive unit can be subjected to scale feedback control using the linear scale provided outside the drive unit. Therefore, even if the moving load acting on the work held on the top table acts on the linear motion mechanism in one axial direction of each drive unit as an external force and mechanical distortion or the like occurs in the linear motion mechanism, Not affected. For this reason, highly accurate position control of each drive unit can be performed. Thereby, highly accurate position control of the workpiece | work hold | maintained at a top table can be performed.

(9) According to the alignment stage according to the present invention, the workpiece on which the moving load acts can be held in a state where the workpiece is positioned with high accuracy in the three axis directions of X, Y, and θ. Furthermore, it is possible to perform highly accurate position correction in the three axis directions of X, Y, and θ with the moving load acting.

It is a partial cutting schematic plan view which shows one Embodiment of the alignment stage of this invention. It is a schematic side view of the alignment stage of FIG. It is a cutting | disconnection top view of the support unit in the alignment stage of FIG. FIG. 3B is a view in the direction of arrows AA in FIG. 3A. It is a BB direction arrow line view of FIG. 3A. FIG. 2 is a cut plan view of a drive unit in the alignment stage of FIG. 1. FIG. 4B is a view in the CC direction of FIG. 4A. FIG. 4B is a DD direction view of FIG. 4A. It is a schematic diagram which shows arrangement | positioning of the support unit regarding each load moving direction in the alignment stage of FIG. 1, and each drive unit. It is a schematic plan view which shows the other form of implementation of this invention. It is a schematic plan view which shows the application example of embodiment of FIG. It is a partially cut perspective view which shows the outline | summary of an example of the alignment stage proposed conventionally. It is a perspective view which expands and shows the drive unit in the alignment stage of FIG.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

1 to 5 show an embodiment of the alignment stage of the present invention.
The top table 4a is arranged above the required dimension of the base 1 on the fixed side. The top table 4a holds a work (not shown) on which a moving load acts, for example, a plate or a printing target on which the moving load acts by pressing a blanket roll that rotates during offset printing while relatively moving. Between the base 1 and the top table 4a, the movement direction of the moving load acting on the workpiece (not shown) (hereinafter simply referred to as the load movement direction is indicated by an arrow L in the figure. The same applies to FIGS. 6 and 7. )) In a staggered arrangement, for example, in the center of the top table 4a in a staggered arrangement of 2 places-1 place-2 places in the direction perpendicular to the load movement direction L in order from the upstream side of the load movement direction L. The support unit 13 and the four drive units 14A, 14B, 14C, and 14D are arranged at five locations corresponding to the square portions. The support unit 13 is composed of a guide that can be slid in two directions orthogonal to each other and a pivot bearing 8 on the upper side thereof, and has three degrees of freedom of X, Y, and θ at the upper end with respect to the lower end. The four drive units 14A, 14B, 14C, and 14D have a uniaxial linear motion mechanism, for example, a ball screw linear motion mechanism 9 similar to that shown in FIGS. It comprises. Of the four drive units 14, the direction of the ball screw linear motion mechanism 9 of the two drive units 14A and 14B and the direction of the ball screw linear motion mechanism 9 of the remaining two drive units 14C and 14D are within the horizontal plane. Arrange so that they are orthogonal. In this state, the lower end portion and the upper end portion of the support unit 13 and each drive unit 14 are respectively attached to the corresponding portions of the base 1 and the top table 4a to constitute the alignment stage of the present invention.

As shown in FIGS. 3A, 3B, and 3C, the support unit 13 is back-to-back with a lower guide rail 15 extending in the horizontal direction and a lower guide block 16a and an upper guide block 16b arranged orthogonally. The lower guide block 16a in the integrated guide block 16 is slidably attached. On the upper side of the upper guide block 16b of the guide block 16, an upper guide rail 17 extending in the horizontal direction perpendicular to the lower guide rail 15 is held so as to be slidable in the longitudinal direction. In this way, a guide that is slidable in two orthogonal directions is formed by connecting the linear motion guides of the upper and lower stages to the back surface. Further, the swivel bearing 8 is attached to the upper side of the upper guide rail 17. Thereby, the slide of the lower guide block 16a of the guide block 16 along the lower guide rail 15; the slide of the upper guide rail 17 in the longitudinal direction with respect to the upper guide block 16b of the guide block 16; Thus, with the lower guide rail 15 serving as the lower end of the support unit 13 as a reference, three degrees of freedom of X, Y, and θ can be obtained at the top of the slewing bearing 8 serving as the upper end of the support unit 13.

As shown in FIGS. 4A, 4B, and 4C, each drive unit 14A, 14B, 14C, and 14D includes a lower guide rail 15 and a guide block 16 that are the same as the support unit 13 shown in FIGS. 3A, 3B, and 3C. In addition to the configuration including the upper guide rail 17 and the swivel bearing 8, the ball screw linear motion mechanism 9 is disposed in parallel with the lower guide rail 15. Further, the nut member 12 of the ball screw linear motion mechanism 9 is connected to the lower guide block 16 a of the guide block 16 via a connecting member 18. Thereby, the guide block 16 can be moved along the longitudinal direction of the lower guide rail 15 together with the nut member 12 by the ball screw linear motion mechanism 9.

As shown in FIG. 1, the support unit 13 is positioned at a position corresponding to the center of the top table 4 a on the base 1 so that the lower guide rail 15 is along either the X-axis direction or the Y-axis direction. (In the figure, a posture along the X-axis direction is shown). The lower guide rail 15 is attached to a corresponding portion of the base 1.

As shown in FIGS. 1 and 2, among the four locations corresponding to the square portions of the top table 4a on the base 1, two locations corresponding to one diagonal position of the top table 4a are provided at the drive unit 14A. And 14B are arranged with the ball screw linear motion mechanism 9 in a posture along the Y-axis direction. The drive units 14C and 14D are arranged at two positions corresponding to the other diagonal position of the top table 4a so that the ball screw linear movement mechanism 9 is in a posture along the X-axis direction. Each drive unit 14A, 14B, 14C, 14D has a lower stage so that each servomotor 10 provided in each ball screw linear motion mechanism 9 protrudes outward from the outer peripheral edge of the base 1. The guide rail 15 and the ball screw linear motion mechanism 9 are attached to corresponding portions of the base 1.

As shown in FIG. 5, the two drive units 14A and 14C on the upstream side of the load movement direction L, which are arranged in a staggered manner along the load movement direction L, the support unit 13, and the load movement The two drive units 14D and 14B on the downstream side in the direction L are arranged such that the regions M of the slewing bearings 8 in the load movement direction L are somewhat overlapped. Although not shown in the drawing, the loads of the slewing bearings 8 of the drive units 14A and 14C, the support unit 13, and the drive units 14D and 14B that are sequentially arranged in a staggered arrangement along the load movement direction L are described. Between the areas M occupying in the movement direction L, a gap having a dimension within a range that is narrower than the width of the movement load applied to the workpiece (not shown) held on the top table 4a may be formed. Thereby, the moving load along the load moving direction L with respect to the workpiece (not shown) held on the top table 4a attached to the upper side of the support unit 13 and the swivel bearing 8 of each drive unit 14A, 14B, 14C, 14D. Is applied to the moving load from the two drive units 14A and 14C on the upstream side in the load moving direction L, which are sequentially arranged in a staggered arrangement along the load moving direction L, through the support unit 13 and the load. The two drive units 14D and 14B on the downstream side in the moving direction L can be continuously received. Thereby, while the said moving load is acting on the said top table 4a, possibility that the support rigidity of a perpendicular direction will fall can be reduced.

On the base 1, along the lower guide rail 15 of each drive unit 14, there is a movement locus along the lower guide rail 15 of the guide block 16 at a location near the guide block 16 that moves via the lower guide block 16 a. A linear scale 19 arranged along the line is provided. As a result, the displacement amount of the guide block 16 can be detected with the required position in the longitudinal direction of the lower guide rail 15, for example, the center in the longitudinal direction as the origin. Based on the detection signal of the linear scale 19, a controller (not shown) gives a command to the ball screw linear motion mechanism 9 of the corresponding drive unit 14. Thereby, scale feedback control can be performed on the position of the guide block 16 that is moved along the longitudinal direction of the lower guide rail 15.

In addition, the same components as those shown in FIGS. 8 and 9 are denoted by the same reference numerals.
When the alignment stage of the present invention having the above configuration is used, the movement along the X-axis direction of each guide block 16 of each drive unit 14C, 14D provided with the ball screw linear motion mechanism 9 along the X-axis direction is stopped. In this state, the drive units 14A and 14B having the ball screw linear motion mechanism 9 along the Y-axis direction synchronize the guide blocks 16 in the same direction along the Y-axis direction by driving the ball screw linear motion mechanism 9. To move. As a result, the top table 4a moves in the Y-axis direction with the movement direction and movement amount corresponding to the movement direction and movement amount of each guide block 16.

Further, each guide block 16 is driven by each drive unit 14C, 14D by driving each ball screw linear motion mechanism 9 in a state where movement of each guide block 16 of each drive unit 14A, 14B along the Y-axis direction is stopped. Are moved synchronously in the same direction along the X-axis direction. Then, the top table 4a moves in the X-axis direction with the movement direction and movement amount corresponding to the movement direction and movement amount.

Accordingly, the guide blocks 16 of the drive units 14A and 14B are moved synchronously in the same direction along the Y-axis direction, and at the same time, the guide blocks 16 of the drive units 14C and 14D are moved along the X-axis direction. When the top table 4a is moved in synchronization with the direction, the movement direction and amount of movement of the guide blocks 16 of the drive units 14A and 14B in the Y-axis direction and the guide blocks of the drive units 14C and 14D. A vector in which the movement direction and movement amount of 16 X-axis directions are combined, and it moves obliquely in the XY plane.

Further, the guide blocks 16 of the drive units 14A, 14B, 14C, and 14D are synchronized with each ball screw linear movement mechanism 9 in a direction close to the servo motor 10 or in a direction away from the servo motor 10. When moved, the top table 4a rotates in the counterclockwise direction in plan view or the clockwise direction in plan view, with the center of the top table 4a as the center of rotation.

Furthermore, when the top table 4a is moved in the XY plane, that is, when moved in the X-axis direction, when moved in the Y-axis direction, or when moved obliquely in the XY plane, The movement of the guide blocks 16 of the drive units 14A, 14B, 14C, 14D and the movement of the guide blocks 16 of the drive units 14A, 14B, 14C, 14D when the top table 4a is rotated are combined (synthesized). Thus, the top table 4a can be rotated while being horizontally moved in the XY plane.

As described above, according to the alignment stage of the present invention, the plate, the object to be printed, and other work (not shown) held on the top table 4a are moved horizontally in the XY plane of the top table 4a and the rotation angle θ is set. By moving in combination with rotation, the position of the workpiece can be corrected in the three-axis directions of X, Y, and θ.

Further, even when a moving load acts on the workpiece (not shown) held on the top table 4a along the load moving direction L, the moving load acting on the top table 4a is changed in the load moving direction L. The drive units 14A and 14C, the support unit 13, and the drive units 14D and 14B, which are arranged in a staggered manner in order, can be continuously received. Thereby, the rigidity of a perpendicular direction can be improved and the deformation amount which deform | transforms so that the said top table 4a may bend by the said moving load can be reduced. Therefore, it is possible to reduce the possibility of the positional deviation of the workpiece (not shown) due to the deformation of the top table 4a.

Furthermore, the alignment stage of the present invention includes a top table 4a, two drive units 14A and 14B each including a ball screw linear motion mechanism 9 along the Y-axis direction, and a ball screw linear motion mechanism 9 along the X-axis direction. The two drive units 14C and 14D are used for movement. For this reason, the horizontal rigidity along the X-axis direction and the horizontal rigidity along the Y-axis direction can be made equal.

Therefore, when a movement load is applied to a workpiece (not shown) held on the top table 4a, when the top table 4a is moved to correct the position of the workpiece (not shown), movement in the X-axis direction and Y It is possible to prevent the possibility of deviation in the movement in the axial direction. Then, a desired position correction can be performed on the workpiece (not shown).

Further, in the alignment stage of the present invention, the drive units 14A, 14B, 14C, and 14D are subjected to scale feedback control using the linear scale 19 provided outside the drive units 14A, 14B, 14C, and 14D. Yes. For this reason, a moving load acting on a workpiece (not shown) held on the top table acts on each ball screw linear motion mechanism 9 of each of the drive units 14A, 14B, 14C, 14D as an external force. Even if the thrust transmission parts such as the screw shaft 11 and the nut member 12 of the mechanism 9 are bent or rattled, the guide blocks 16 of the drive units 14A, 14B, 14C, and 14D are It can be moved to a desired position detected by the linear scale 19. Thereby, highly accurate position control of the top table 4a can be performed.

Furthermore, in the alignment stage of the present invention, all the servo motors 10 that are the drive sources of the ball screw linear motion mechanisms 9 of the drive units 14A, 14B, 14C, and 14D are projected to the outer peripheral side of the base 1. It is arranged. For this reason, the heat generated by each servo motor 10 can be efficiently dissipated into the atmosphere. Therefore, thermal deformation of the base 1 and the top table 4a due to the heat generation of each servo motor 10 can be suppressed. Thereby, it is possible to reduce the possibility that a position shift occurs in a work (not shown) held on the top table 4a due to the influence of thermal deformation of the base 1 and the top table 4a.

As described above, according to the alignment stage of the present invention, a workpiece (not shown) on which a moving load acts can be held in a state in which high-precision positioning is performed in the three axis directions of X, Y, and θ. Furthermore, it is possible to perform highly accurate position correction of the workpiece (not shown) in the three-axis directions of X, Y, and θ while a moving load is applied.

Next, FIG. 6 shows another embodiment of the present invention. In this embodiment, the arrangement of units between the base 1 and the top table 4a in the embodiment shown in FIGS. 1 to 5 is changed. That is, in the embodiment shown in FIGS. 1 to 5, the number of units arranged in the direction perpendicular to the load movement direction L between the base 1 and the top table 4a is two in order from the upstream side of the load movement direction L. The drive units 14A, 14B, 14C, and 14D and the support units 13 are respectively arranged at positions corresponding to the square and center of the top table 4a so as to be in a staggered arrangement of −1 piece. In the embodiment shown in FIG. 6, instead of this arrangement, the number of units arranged in the direction perpendicular to the load movement direction L is 1 to 2 in a staggered arrangement in order from the upstream side of the load movement direction L. In addition, four drive units 14A, 14B, 14C, and 14D are arranged on each of four lines connecting the intermediate position of each side of the top table 4a and the center of the top table 4a.

One drive unit 14A on the upstream side of the load movement direction L, which is arranged in a staggered manner along the load movement direction L, two drive units 14C and 14D in the middle of the load movement direction L, and load movement One drive unit 14B on the downstream side in the direction L is arranged so that the regions M of the slewing bearings 8 occupying in the load movement direction L are somewhat overlapped. Moreover, although not shown in figure, the said load moving direction of each slewing bearing 8 of drive unit 14A, drive unit 14C, 14D, and drive unit 14B arrange | positioned in order with zigzag arrangement along the said load moving direction L. Between the areas M occupying L, a gap having a size within a range narrower than the width of the moving load that acts on the workpiece (not shown) held on the top table 4a may be formed.

In addition, the same components as those shown in FIGS. 1 to 5 are denoted by the same reference numerals.
Also according to this embodiment, the same effect as that of the embodiment of FIGS. 1 to 5 can be obtained. Furthermore, since the four drive units 14A, 14B, 14C, and 14D can be arranged closer to each other, it is possible to obtain an advantageous configuration when applied to an alignment stage having a smaller planar shape.

In addition, this invention is not limited only to the said embodiment, In the range of the summary of this invention, it can change suitably. For example, in the embodiment shown in FIGS. 1 to 5, the top table 4a is square, and one support unit 13 and four drive units 14A, 14B, 14C, and 14D are centered on the center of the top table 4a. It is arranged at a position that is rotationally symmetric. However, the planar shape of the top table 4a may be enlarged or rectangular to correspond to the planar shape of a workpiece (not shown) to be supported. In this case, you may increase the number of the support units 13 arrange | positioned between each drive unit 14A, 14B, 14C, 14D of the square part of the said top table 4a. That is, for example, when the size of the top table 4a is large, the number of units aligned in the direction perpendicular to the load movement direction L of each drive unit 14A, 14B, 14C, 14D and each support unit 13 is upstream of the load movement direction L. Alternatively, a staggered arrangement of 3-2 pieces-3 pieces-2 pieces-3, etc. may be arranged in order from the side. When the top table 4a is a rectangle that is long along the load movement direction L, the number of units arranged in the direction perpendicular to the load movement direction L of each drive unit 14A, 14B, 14C, 14D and the support unit 13 is the load movement. A staggered arrangement of 2-1-2-1-2 etc. may be arranged in order from the upstream side in the direction L. When the top table 4a is a rectangle that is long in the direction orthogonal to the load movement direction L, the number of units arranged in the direction perpendicular to the load movement direction L of each drive unit 14A, 14B, 14C, 14D and the support unit 13 is as follows. A staggered arrangement of 3-2 pieces-3 pieces, 4 pieces-3 pieces-4 pieces, etc. in order from the upstream side in the load moving direction L may be employed.

Further, as shown in FIG. 7, four drive units 14A, 14B, 14C, and 14D interposed between the base 1 and the top table 4a are connected to the slewing bearings 8 of the drive units 14A, 14B, 14C, and 14D. The quadrangle formed by connecting the two may be arranged so as to be inclined at a required angle of less than 45 degrees with respect to the load movement direction L. By adopting such an arrangement, the drive units 14A, 14B, 14C, and 14D may have a staggered arrangement that is uneven in the left and right directions with respect to the load movement direction L. In the case of the arrangement as shown in FIG. 7, among the drive units 14A, 14B, 14C, and 14D, the drive units 14C and 14D that are located second and third along the load movement direction L are shown. What is necessary is just to arrange | position so that the area | regions M which occupy in the said load moving direction L of each slewing bearing 8 may overlap a little. Alternatively, a gap having a dimension narrower than the width of the moving load to be applied to the workpiece (not shown) held on the top table 4a is provided between the regions M in the load moving direction L of the slewing bearings 8 of the drive units 14C and 14D. The arrangement may be such that it is formed.

As shown in FIGS. 8 and 9, the guides that can slide in the two directions orthogonal to each other in the support unit 13 and the drive units 14A, 14B, 14C, and 14D The guide rail 6b of the upper linear guide 5b may be attached to the guide block 7a of the moving guide 5a.

The main purpose is to increase the vertical rigidity of the top table 4a when a moving load acts on a workpiece (not shown) held on the top table 4a, and the moving load is applied to the workpiece (not shown) held on the top table 4a. When there is no need to correct the position in the acted state, and there is no problem even if there is a difference in the horizontal rigidity between the X-axis direction and the Y-axis direction for the top table 4a, each drive in each of the above embodiments Any one of the units 14A, 14B, 14C, and 14D may be replaced with the support unit 13.

It is desirable that an external linear scale 19 is attached to each drive unit 14A, 14B, 14C, 14D so that the movement of the guide block 16 along the lower guide rail 15 can be scale feedback controlled. However, the mechanical rigidity of each ball screw linear movement mechanism 9 such as the rigidity of the screw shaft 11 of each ball screw linear movement mechanism 9 of each of the drive units 14A, 14B, 14C, 14D is sufficiently high. Even if a moving load applied to a workpiece (not shown) held on the table 4a acts on each ball screw linear motion mechanism 9 as an external force, the thrust transmission portion of each ball screw linear motion mechanism 9 can be easily bent or rattled. If not, the movement of the guide block 16 along the lower guide rail 15 of each drive unit 14A, 14B, 14C, 14D is determined based on the signal of the encoder built in the servo motor 10 of each ball screw linear motion mechanism 9. It is good also as a structure to control.

From the viewpoint of heat dissipation, it is desirable that each servo motor 10 serving as a drive source of each ball screw linear motion mechanism 9 of each drive unit 14A, 14B, 14C, 14D is disposed so as to protrude outside the base 1. However, when the heat generation amount of each servo motor 10 is sufficiently smaller than the heat capacity of the base 1, the top table 4a, or other components, or for releasing heat to the outside of the alignment stage to each servo motor. Since the heat dissipation mechanism is separately provided, the base table 1, the top table 4a, and other components are held by the top table 4a due to the heat generated by the servo motor 10 of each ball screw linear motion mechanism 9. If there is no possibility that the workpiece will be displaced, the servo motors 10 of the ball screw linear motion mechanisms 9 may be arranged between the base 1 and the top table 4a.

The linear motion mechanism for moving each guide block 16 of each drive unit 14A, 14B, 14C, 14D along the longitudinal direction of the lower guide rail 15 via the lower guide block 16a should satisfy the following conditions. For example, any type of linear motion mechanism other than the ball screw linear motion mechanism 9 may be employed. That is, even if the moving load acting on the top table 4a acts on the linear motion mechanism as an external force, the corresponding position of the guide block 16 can be maintained. Further, if necessary, the corresponding guide block 16 can be driven in a state where the moving load acting on the top table 4a acts as an external force.

As an alignment stage for any machine or device other than an alignment stage for holding a plate or printing object in an offset printing device, as long as it is necessary to hold and align the workpiece to which a moving load acts You may apply.

Of course, various changes can be made without departing from the scope of the present invention.

According to the alignment stage according to the present invention, the workpiece on which the moving load acts can be held in a state where the workpiece is positioned with high accuracy in the three axial directions of X, Y, and θ. Furthermore, it is possible to perform highly accurate position correction in the three axis directions of X, Y, and θ with the moving load acting. Thereby, it can utilize for the alignment stage used in order to align the workpiece | work which receives a moving load.

1 Base 4a Top table 8 Slewing bearing 9 Ball screw linear motion mechanism (linear motion mechanism)
10 Servo motor (motor)
11 Screw shaft 12 Nut member 13 Support unit 14 Drive unit 15 Lower guide rail (guide)
16 Guide block (guide)
17 Upper guide rail (guide)
19 Linear scale

Claims (11)

Base and
A top table for holding a work on which a moving load acts, which is arranged at a position above the base;
A required number of support units having three degrees of freedom of X, Y, and θ, comprising guides slidable in two orthogonal directions, and swivel bearings provided on the guides;
The support unit includes at least three drive units each including a uniaxial linear motion mechanism. The support unit and the drive unit move the moving load between the base and the top table. Provided in a staggered arrangement along the direction,
An alignment stage in which the driving directions of the two driving units by the linear motion mechanisms and the driving directions of the remaining driving units by the linear motion mechanisms are orthogonal to each other in the XY plane. The alignment stage according to claim 1, wherein the staggered arrangement is a portion corresponding to a square portion and a center of the top table. The staggered arrangement is a location corresponding to the square portion and the center of the top table, and a drive unit is provided at a location corresponding to the square portion of the top table, and a location corresponding to the center of the top table. The alignment stage according to claim 1, wherein the support unit is provided. Base and
A top table for holding a work on which a moving load acts, which is arranged at a position above the base;
A guide unit slidable in two orthogonal directions, and a drive unit having a three-degree-of-freedom of X, Y, and θ and a uniaxial linear motion mechanism, which is composed of a slewing bearing provided on the guide. The drive unit is provided in a staggered arrangement along the moving direction of the moving load between the base and the top table,
An alignment stage in which the driving direction of the two driving units by the linear motion mechanism and the driving direction of the remaining two driving units by the linear motion mechanism are orthogonal to each other in the XY plane. 5. The alignment stage according to claim 1, wherein the staggered arrangement is a portion corresponding to a line connecting an intermediate position of each side of the top table and a center of the top table. The linear motion mechanism includes a motor, a screw shaft connected to the output shaft of the motor, and a ball screw linear motion mechanism including a nut member screwed to the screw shaft. The alignment stage according to any one of claims 1 to 4, wherein the alignment stage is arranged so as to protrude toward the side. The linear motion mechanism includes a motor, a screw shaft connected to the output shaft of the motor, and a ball screw linear motion mechanism including a nut member screwed to the screw shaft. The alignment stage according to claim 5, wherein the alignment stage is arranged so as to protrude toward the side. The alignment stage according to any one of claims 1 to 4, wherein a linear scale is provided on a base in the vicinity of each drive unit for detecting a drive amount by a linear motion mechanism in one axial direction of each drive unit. 6. An alignment stage according to claim 5, wherein a linear scale for detecting a drive amount by a linear motion mechanism in one axial direction of each drive unit is provided on a base in the vicinity of each drive unit. The alignment stage according to claim 6, wherein a linear scale for detecting a driving amount by a linear motion mechanism in one axial direction of each driving unit is provided on a base in the vicinity of each driving unit. The alignment stage according to claim 7, wherein a linear scale for detecting a drive amount by a linear motion mechanism in a uniaxial direction of each drive unit is provided on a base in the vicinity of each drive unit.

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