JP3173976B2 - XY table - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the setting of a processing shape by linearly moving an upper table and a lower table in two directions orthogonal to each other when processing a mounted workpiece by laser light or the like. And an XY table which supplies compressed air between each table and a rail supporting the table to enable smooth table movement.

[0002]

2. Description of the Related Art An XY table mounted on a laser beam machine or the like generally has an X table (upper table) on which a workpiece is mounted via a suction table or the like, and slidably supports the X table. A pair of X-axis rails (upper rails), first driving means such as a linear motor that linearly reciprocates the X-table along these X-axis rails, and a Y table (lower) on which these X-axis rails are mounted Table), a pair of Y-axis rails (lower rails) extending in a direction orthogonal to the X-axis rails and slidably supporting the Y-table, and a linear reciprocating linearly moving Y-table along these Y-axis rails. A second driving means such as a motor is provided, and compressed air is supplied from an air nozzle provided on the table side between the X table and each X-axis rail and between the Y table and each Y-axis rail. It has become way. That is, by sending compressed air between each table and the rail supporting the table to form an air gap, frictional force when moving each table along the rail can be significantly reduced. As a result, the workpiece can be smoothly transferred in the X-axis direction and the Y-axis direction.

[0003] In order to precisely process a workpiece in units of microns using such an XY table, it is necessary to minimize the effects of expansion and contraction due to temperature changes. As a material for the X-axis rail, the Y-axis rail, and the like, a stone material such as granite having excellent mechanical strength and a small coefficient of thermal expansion is considered suitable.

[0004]

By the way, this kind of X
In the Y table, when the X table (upper table) is located near the center on the Y table (lower table), the load is substantially evenly distributed on the pair of Y-axis rails (lower rail) supporting the Y table. Therefore, the air gap between the upper surface of each Y-axis rail and the Y table is kept substantially equal, but when the X table is located at the side edge on the Y table, it is disposed below the Y table. The load of the X table is concentrated on one of the Y-axis rails, and the air gap between the upper surface of the Y-axis rail and the Y table is narrowed. A phenomenon occurs in which the air gap becomes wider on the contrary. The variation of the air gap between the Y-axis rails thus generated is so small in dimension that the inclination of the Y table itself does not matter, but the air gap between the upper surface of the Y-axis rail and the Y table is not a problem. When the air spreads, the compressed air to be blown toward the side surface of the Y-axis rail and discharged downward flows into an upper wide air gap, so that an irregular air flow is easily generated. The upper air gap fluctuates little by little and Y
There is a problem that vibration is easily generated on the table,
The improvement has been desired in order to increase the processing accuracy.

The present invention has been made in view of the above-mentioned problems of the prior art, and has an object to prevent vibrations caused by an irregular flow of compressed air in an air gap and improve processing accuracy. It is to provide an XY table that can be achieved.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an upper table on which a workpiece is mounted, an upper rail group for movably supporting the upper table, and an upper rail group along the upper rail group. a first drive means for the upper table is linearly reciprocated, and a lower table placing the on the rail group, lower rail group movably supporting the lower table extends in a direction perpendicular to the upper rail group and and the center rail, this
Along these lower rail group and center rail and a second drive means for reciprocating linear movement of the lower table,
A large number of air nozzles for supplying compressed air for reducing frictional force are provided at predetermined intervals on a flat opposing surface of the upper table opposing the upper rail group, and the lower rail of the lower table is provided. Flat pairs opposing the top and sides of the group
A large number of air nozzles for supplying compressed air for reducing the frictional force are provided at predetermined intervals on a facing surface and a flat facing surface facing the upper surface of the center rail , respectively, and a large number of air nozzles are provided. This is achieved by providing an air exhaust groove for partitioning the adjacent air nozzles on the facing surface. Further, it is more preferable that the exhaust groove provided around each air nozzle is set to have a square shape (or a letter-shaped shape) having the air nozzle substantially at the center.

[0007]

When the exhaust groove is provided on the flat rail-facing surface of the upper table or the lower table, the compressed air in the air gap tends to flow through the exhaust groove having a large gap, so that the upper surface of the rail is closed. Even if the air gap is slightly widened, the phenomenon that a large amount of compressed air flows into the air gap from other places to generate an irregular air flow hardly occurs. In other words, the provision of the exhaust groove makes the discharge passage of the compressed air stable, so that it is possible to prevent a small change in the air gap caused by the irregular air flow. In particular, the air gap depends on the position of the upper table.
Air blow on the lower table side where
The exposed surface is located on the top and both sides of the lower rail group.
Opposing flat opposing surface and upper surface of center rail
By providing exhaust grooves on the flat opposing surface,
Stabilization of the compressed air discharge flow path inside the
Lower table, lower rail group and center rail
Can be extremely reduced.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. Here, FIG. 1 is a front view of an XY table according to the present embodiment, FIG. 2 is a side view of the XY table, a part of which is omitted, and FIG. 3 is an overall side view of a laser processing machine including the XY table. 4 is a side view of a portion corresponding to FIG. 3 of the safety cover covering the laser processing machine, FIG. 5 is a side view of a Y-axis linear motor incorporated in the XY table shown in FIGS. FIG. 7 is a cross-sectional view showing a leg of the X table of the table, FIG. 7 is a plan view showing an air blowing surface of the leg of the X table shown in FIG. 6, and FIG. 8 is a plan view showing a suction table of the XY table. FIG. 9 is an explanatory view showing a support structure of the suction table shown in FIG.

The XY table according to the present embodiment is employed in the laser beam machine shown in FIG. In other words, this laser processing machine has a processing machine body 1 that guides a laser beam (YAG laser) supplied from a laser oscillator 5 by an optical system including a lens group and a beam splitter and irradiates the workpiece with a laser beam. An XY table 2 capable of transferring a workpiece (glass substrate) in two directions orthogonal to each other by a linear motor, a surface plate (base plate) 3 on which the processing machine body 1 and the XY table 2 are mounted, and a surface plate 3 A safety cover 7 (see FIG. 4) having a cover frame 6 indicated by a dashed line in FIG. 3 as a support frame is used for the laser processing machine, the vacuum pump 8 and the like. Covering. Reference numeral 21 in FIG. 1 indicates an optical surface plate on which the processing machine main body 1 is mounted.
It is supported on the surface plate 3 through the base 2.

The XY table 2 has a shaft hole 9a provided at the center of the bottom surface and a large number of suction holes 9b communicating with the vacuum pump 8, and the mounted workpiece is moved through the suction holes 9b. A suction table 9 that can be suction-fixed by suction of air; and an X table 10 that inserts a cylindrical support shaft 10a into the shaft hole 9a of the suction table 9 to rotatably support the suction table 9. A pair of parallel X-axis rails 11a slidably supporting the X-table 10, provided on both side edges thereof, and having a concave-shaped cross-section, and the X-axis mounted inside the support 11; An X-axis linear motor 12 for linearly reciprocating the X table 10 along the rail 11a, an X-axis linear encoder 13 for detecting the position data of the X table 10, and a Y on which the support base 11 is mounted.
A table 14, three Y-axis rails 15, 16 extending in a direction orthogonal to the X-axis rail portion 11a and slidably supporting the Y table 14, and a group of Y-axis rails 15, 1;
It is mainly composed of a Y-axis linear motor 17 for linearly reciprocating the Y table 14 along the line 6 and a Y-axis linear encoder 18 for detecting position data of the Y table 14. However, the X table 10 and each X axis rail 11
a, Y table 14 and each Y-axis rail 15, 16
An air gap is formed by blowing compressed air from an air nozzle provided on the table side, and the workpiece is moved in the X-axis direction and the Y-axis direction by reducing the frictional force with these air gaps. It can be transported smoothly.

In this embodiment, in order to minimize the influence of expansion and contraction caused by a temperature change, the suction table 9 and X
Table 10, support 11, Y table 14, and Y
As a stone which is a material such as axial rails groups 15 and 16, using the Indian black called granite, and,
Granite called Rustenburg is used as a stone material for the surface plate 3.

The laser beam machine provided with such an XY table 2 moves the workpiece mounted on the suction table 9 in a horizontal plane with high positional accuracy by controlling the drive of the XY table 2. By moving the workpiece along a predetermined trajectory with respect to a spot-like laser beam (beam spot) emitted from the tip (objective lens) of the optical system of the processing machine body 1, A desired processing pattern by beam irradiation can be drawn on a workpiece. Specifically, in a manufacturing process of a liquid crystal display element of a full-color display, a work in which a stripe-shaped transparent electrode extending in one direction on a glass substrate and a color filter laminated on the electrode are formed as a workpiece. The color filter is mounted on the suction table 9 and irradiated with a beam spot by the processing machine main body 1 while appropriately transferring the workpiece by the XY table 2, so that the color filters are arranged at a constant pitch interval in a direction orthogonal to the longitudinal direction. Can be removed.

The linear motors 12 and 17 incorporated in the XY table 2 generate a strong magnetic force for driving heavy objects. In order to prevent the magnetic force of the linear motors 12 and 17 from exerting a bad influence on the machine, the laser processing machine is completely covered with a safety cover 7 mainly made of a ferromagnetic material. That is, as shown in FIGS. 3 and 4, the safety cover 7 is a cover frame 6 serving as a support frame.
A steel plate or a demagnetizing plate is attached to the SUS304. Specifically, FIG. 4A shows a portion where a stainless steel plate of SUS304 is attached, and FIG. 4A shows a portion where a stainless steel plate of SUS304 is attached. A two-layer structure with a demagnetizing plate added to enhance the demagnetizing effect. Of these, the U part is a double-sided cover that can be opened and closed. In the D part, the outside of the colored acrylic plate has the same configuration as the C part. It has a three-layer structure. As described above, if the laser processing machine is covered with the safety cover 7 having a demagnetizing effect, and where a strong magnetic force is expected in the vicinity of the linear motors 12 and 17, a two-layer structure is used to enhance the demagnetizing effect. There is no possibility that the magnetic force of 12, 17 will adversely affect the peripheral equipment, and the adjustment of the optical system of the processing machine body 1 can be easily performed by opening the double-sided cover of the c portion. In addition, when directly checking whether or not the laser beam is correctly irradiated on the workpiece, if the double-sided cover of the portion D is opened, the visual check can be safely performed via the colored acrylic plate.

Next, a detailed configuration of the XY table according to the embodiment will be described.

As shown in FIG. 8, a large number of suction holes 9b communicated with the vacuum pump 8 are provided on the upper surface of the suction table 9, and the vacuum pump 8 is connected to the suction pump 9 via a group of these suction holes 9b.
By sucking air, the suction table 9 can suction-fix the mounted workpiece.

As shown in FIG. 9, a shaft hole 9a for inserting a support shaft 10a of the X table 10 is provided at the center of the bottom surface of the suction table 9, and a shaft around the support shaft 10a is provided. Maintaining a circumferential gap, that is, a gap between the outer wall surface of the support shaft 10a and the inner wall surface of the shaft hole 9a, in which a large number of resin balls (resin spacers) 19a slightly larger than the gap of the circumferential shaft gap are mixed with grease. Agent 19 is filled. However, the support shaft 10a is a convex body made of stainless steel, and the inner wall of the shaft hole 9a is also formed in a stainless steel bearing structure. The support shaft 10 a rotatably supports the suction table 9 via the gap maintaining agent 17, and is used for positioning the workpiece suction-fixed on the suction table 9 with respect to the X table 10 with high accuracy. The motor 20 shown in FIG.
Is driven to move the suction table 9 to the support shaft 10a.
Can be appropriately rotated around the rotation center. While the gap around the axis is 15 to 16 μm, the gap maintaining agent 19 disperses the resin balls 19 a having a diameter of 20 μm before filling, so that each resin ball 19 a is crushed after filling. As a result, the gap around the axial gap is always kept uniform without strict dimensional control, and there is no play near the center of rotation of the suction table 9. It has become. When the positioning for rotating the suction table 9 is completed, the X table 10 can suck and fix the suction table 9 by sucking air from the air nozzle on the upper surface side.

As shown in FIG. 2, the X table 10 includes a support table 1 having a pair of parallel X axis rails 11a.
An X-axis linear motor 12 for reciprocatingly moving the X-table 10 along the X-axis rail portion 11a is installed inside the support base 11. The linear motor 12 includes a coil 12a integrated with the X table 10, a magnet 12b and a yoke 12c extending in parallel with the X-axis rail 11a, and the like. Based on the position data of the table 10, the position of the X table 10 is controlled via the coil 12a which is a movable part. The X-axis linear encoder 13 is configured such that a light-emitting element and a light-receiving element are integrated with an X-table 10 to constitute a detection unit 13a, and a scale (linear scale) 13b fixed to one X-axis rail 11a has a light-emitting element. And the reflected light is captured by the light receiving element, and the position of the moving X table 10 can be detected in real time.

In this embodiment, the X table 10 is slidably supported by a pair of parallel X-axis rails 11a provided on both side edges of the support base 11.
It is easy to give a high degree of parallelism to the pair of X-axis rails 11a, and when the support base 11 is installed on the Y table 14, the positional accuracy of the rails 11a is easily increased. be able to. Moreover, in the present embodiment, since the point of action P of the magnetic driving force generated by the X-axis linear motor 12 substantially matches the center of gravity of the X table 10 driven by the linear motor 12, the X table 10 is activated. There is no danger of rattling at the time of stop or stop, and the processing accuracy can be improved.

Next, the supporting structure and driving method of the Y table 14 on which the support base 11 is mounted will be described. The Y table 14 has both side edges sliding by a pair of Y-axis main rails 15. The center portion is slidably supported by a center rail (Y-axis auxiliary rail) 16, and a pair of Y-axis linear motors 17
The Y table 14 is reciprocated along the axis rail groups 15 and 16. As shown in FIG. 5, each of the pair of linear motors 17 includes a coil 17a integrated with the Y table 14, a Y-axis rail group 15,
And a pair of linear motors 17 based on the position data of the Y table 14 output from the Y-axis linear encoder 18.
The position of the Y table 14 is controlled via 7a. The Y-axis linear encoder 18 has a light-emitting element and a light-receiving element integrated at substantially the center of the Y table 14 to constitute a detection section 18a, and emits light at a scale (linear scale) 18b fixed to the center rail 16. The reflected light is captured by the light receiving element by irradiating the light of the element, and the position of the moving Y table 14 can be detected in real time.

That is, in this embodiment, the Y table 14
The center portion of the Y table 14 is supported not only by a pair of Y-axis main rails 15 supporting both side edges of the Y table 14 but also by a center rail 16 located between the two main rails 15. Even if the center rail 16 is located near the center of the Y table 14, the X table 1
Since the Y table 14 does not bend since the load of 0 is received, and even if the X table 10 is positioned at the side edge on the Y table 14, the load of the X table 10 is And the center rail 16 are dispersed and received, so that the air gap between the upper surface of the remaining Y-axis main rail 15 and the Y table 14 does not undesirably widen. The arrows in FIG. 1 indicate the compressed air blown from the Y table 14, and as can be seen from the arrows, the air gap is provided between the upper surface and both side surfaces of each Y-axis main rail 15 and the Y table 10. Are formed, and an air gap is formed between the upper surface of the center rail 16 and the Y table 10.

Further, in this embodiment, the detecting section 18a of the Y-axis linear encoder 18 for detecting the position data of the Y table 14 is installed at a position where the detecting section 18a moves linearly in the vicinity of the center rail 16 integrally with the Y table 14. Therefore, the position data of the Y table 14 detected by the detector 18a is obtained by averaging the relative positions of the Y table 14 with a pair of Y-axis main rails 15 supporting both side edges of the Y table 14. Therefore, the actual position change of the mounted workpiece can be accurately grasped. When the two Y-axis linear motors 17 perform the position control based on the detection result of one Y-axis linear encoder 18 in a synchronized manner as described above, the position control of one of the linear motors 17 is performed. The phenomenon that the moved Y table 14 changes its posture by the position control of the other linear motor 17 does not occur, so that the transferred workpiece can be prevented from being displaced and the processing accuracy can be improved.

Here, the X table 10 and the Y table 14
The shape of the air blowing surface for blowing compressed air toward the X-axis rail unit 11a group and the Y-axis rail group 15, 16 will be described with reference to FIGS. In these figures, the air blowing surface (rail facing surface) 10b of the leg of the X table 10 is shown, but the surface of the X table 10 facing the upper surface of the group of X axis rails 11a, the Y table 14 Among them, the surface facing the upper surface or both side surfaces of the group of Y-axis main rails 15 or the surface facing the upper surface of the center rail 16 is also an air blowing surface having substantially the same shape. Now, the air blowing surface 10b of the illustrated X table 10
Has not only a large number of air nozzles 10c exposed, but also an exhaust groove 10d extending between adjacent air nozzles 10c, so that air is supplied into the air gap via the air nozzles 10c. Compressed air is generated in these exhaust grooves 10 having a relatively large gap.
d, and as a result, the compressed air discharge passage becomes stable. In particular, since a similar exhaust groove is provided on the air blowing surface of the Y table 14 to stabilize the compressed air discharge flow path, the movement of the X table 10 on the Y table 14 causes one of the Y tables to move. Even when the air gap on the upper surface side of the shaft main rail 15 is slightly widened, there is no possibility that a large amount of compressed air flows into the air gap from other places to generate an irregular air flow. It is possible to avoid the occurrence of vibrations caused by the irregular airflow in the air conditioner.

In this embodiment, the air blowing surface has
Although an example is described in which exhaust grooves are provided to extend between adjacent air nozzles, the planar shape of the exhaust grooves provided around each air nozzle may be rectangular or By setting it in the shape of a letter, the discharge passage for compressed air can be further stabilized.

Next, the Y-axis rail group 1 in this embodiment
5 and 16 mounting structures will be described. Y table 1
The pair of Y-axis main rails 15 and center rails 16 that slidably support the base 4 are both inserted into the mounting grooves 3a provided on the upper surface of the surface plate 3 so that the bottoms of the mounting grooves 3a are formed. Since it is designed to be positioned in the width direction on the inner wall surface, even if an external force is applied to the rails 15 and 16 in the width direction as the X table 10 supported on the Y table 14 moves. Since the position of the rails 15 and 16 is regulated by the surface plate 3, there is no fear that the rails 15 and 16 may be displaced.

In this embodiment, as described above, XY
Suction table 9, X table 10, support base 11, Y table 14, Y axis rail group 1 which are constituent elements of table 2
For materials such as 5, 16 and so on, Indian Black (a type of granite) known as a stone material with a low coefficient of thermal expansion and particularly high mechanical strength is selected, so that when used, large tensile force, compressive force, bending stress, etc. The durability of each component of the XY table 2 is increased, and the tables 10, 14 and the support base 11 and each rail group 1 can be used for a long period of time.
Damages such as cracks are less likely to occur in 5,16. In addition, since Rustenburg (a kind of granite) known as a stone having a particularly small coefficient of thermal expansion is selected as the material of the surface plate 3 having a large area on the base of the apparatus, the surface plate 3 has a large area. Also, the amount of expansion and contraction due to temperature change is extremely small.

[0026]

As described above, XY according to the present invention is used.
The table is provided with an exhaust groove extending between the air nozzles adjacent to the flat air blowing surface (rail-facing surface) of the upper table and lower table.
Variation in air gap depending on the position of the table
Air blow surface on the lower table side where
The upper and lower sides of the lower rail group.
Flat opposing surface opposing the opposing surface and the upper surface of the center rail
Since the exhaust groove is provided in the air gap, the discharge path of the compressed air in the air gap becomes stable, and the small fluctuation of the air gap caused by the irregular air flow can be prevented. Therefore, each table is less likely to vibrate, and an excellent effect of improving the processing accuracy is achieved.

[Brief description of the drawings]

FIG. 1 is a front view of an XY table according to the present embodiment.

FIG. 2 is a side view of the XY table, a part of which is not shown.

FIG. 3 is an overall side view of a laser processing machine including the XY table.

FIG. 4 is a side view of a portion corresponding to FIG. 3 of a safety cover covering the laser processing machine.

FIG. 5 is a side view of a Y-axis linear motor incorporated in the XY table shown in FIGS.

FIG. 6 is a sectional view showing a leg of an X table of the XY table.

7 is a plan view showing an air blowing surface of a leg of the X table shown in FIG. 6;

FIG. 8 is a plan view showing a suction table of the XY table.

FIG. 9 is an explanatory view showing a support structure of the suction table shown in FIG. 8;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Processing machine main body 2 XY table 3 Surface plate (base plate) 9 Suction table 10 X table (upper table) 10b Air blowing surface (rail facing surface) 10c Air nozzle 10d Exhaust groove 11 Support base 11a X axis rail part 12 X axis Linear motor (first driving means) 13 X-axis linear encoder 14 Y table (lower table) 15 Y-axis main rail 16 Center rail (Y-axis auxiliary rail) 17 Y-axis linear motor (second driving means) 18 Y-axis Linear encoder

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-59-129634 (JP, A) JP-A-2-57723 (JP, A) JP-A-6-85040 (JP, A) 23890 (JP, B2) Jiko 63-48809 (JP, Y2) Jiko 7-27060 (JP, Y2) Jiko 2-30186 (JP, Y2) (58) Fields surveyed (Int. Cl. ⁷ , DB name) B23K 26/10 B23K 37/00 B23Q 1/38

Claims (5)

(57) [Claims] 1. An upper table on which a workpiece is mounted, an upper rail group for movably supporting the upper table, and a first drive means for linearly reciprocating the upper table along the upper rail group. A lower table on which the upper rail group is mounted, a lower rail group extending in a direction perpendicular to the upper rail group, and a center rail for movably supporting the lower table.
And Lumpur, the lower table along these lower rails group and center rail and a second drive means for reciprocating linear movement, friction reducing the flat facing surface of the upper table that faces the on rail group the air nozzle for supplying a compressed air use is provided a number at predetermined intervals, and the lower tape
Facing the upper surface and both side surfaces of the lower rail group
A large number of air nozzles for supplying compressed air for reducing frictional force are provided at predetermined intervals on a flat opposing surface facing the upper surface of the center rail and a flat opposing surface facing the upper surface of the center rail. On the opposing surface and the opposing surface of the lower table,
An XY table having an air exhaust groove for partitioning between adjacent air nozzles. 2. The XY table according to claim 1, wherein a plane shape of the exhaust groove provided around each of the air nozzles is set to be a square with the air nozzle being substantially at the center. 3. The XY table according to claim 1, wherein a plane shape of the exhaust groove provided around each of the air nozzles is set to a cross shape with the air nozzle being substantially at the center. 4. The X according to claim 1, wherein
A processing machine with an XY table, comprising a Y table. 5. The processing machine with an XY table according to claim 4, wherein the processing machine is a laser processing machine.