JP3803263B2 - XYθ table - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an XYθ table used for positioning a workpiece in a processing apparatus, an assembly apparatus, an inspection apparatus, or the like.
[0002]
[Prior art]
An XYθ table used for positioning a workpiece in a processing apparatus, an assembly apparatus, an inspection apparatus, etc., for example, as shown in FIG. 6, is a thrust rolling of a movable platen 51 arranged in an XY plane expressed by an XY orthogonal coordinate system. Two electric linear actuators 54 that are supported on a fixed platen 53 via a bearing 52 and extend and contract in the Y direction as first driving means on the fixed platen 53 side, and in the X direction as second driving means. One electric linear actuator 55 that expands and contracts is attached, and three linear guides 56 and 57 serving as linear guide means connected to the linear actuators 54 and 55 are attached to the movable platen 51 side.
[0003]
The two sets of linear actuators 54 and the linear guides 56, and the one set of linear actuators 55 and the linear guides 57 are connected to each other by pin coupling so that the linear actuators 54 and 55 are expanded and contracted. The movable platen 51 can be moved not only in parallel but also in rotation in the XY plane.
[0004]
The two linear guides 56 connected to the linear actuators 54 are directed in directions parallel to each other, and the linear guide 57 connected to the linear actuator 55 is directed in a direction orthogonal to the linear guides 56. This is because the amount of expansion / contraction in the Y direction of the linear actuator 54 serving as the first driving means and the amount of expansion / contraction in the X direction of the linear actuator 55 serving as the second driving means are respectively expressed in the Y direction and X direction of the movable platen 51. This is to make it easy to adjust the amount of parallel movement in each of these directions.
[0005]
[Problems to be solved by the invention]
In the conventional XYθ table described above, two linear guides serving as linear motion guide means connected to the first drive means are directed in parallel directions, and one linear guide connected to the second drive means is provided. Since the direction is perpendicular to these parallel linear guides, depending on the direction of movement of the movable platen by each driving means, the driving force of the driving means is the driving force of each connecting portion of the driving means and the linear guide means. You may concentrate on one. For example, when the movable platen is moved almost only by the second drive means, the drive force acts only on one connecting portion between the second drive means and the linear motion guide means.
[0006]
As described above, when the driving force is concentrated on one connecting portion, a large moment load is generated on the movable platen. Therefore, smooth movement of the movable platen is hindered or unintentional rotational movement occurs, and positioning accuracy is increased. There is a problem that decreases.
[0007]
The XYθ table has high rigidity in the vertical direction (vertical direction) because the movable plate is supported by the fixed plate with a wide area, but the rigidity in the horizontal direction (horizontal direction) is not so high. Although this lateral rigidity improvement has been sought before, since the conventional XYθ table increases the lateral rigidity, smooth guidance of the linear motion guiding means is hindered, and positioning accuracy decreases. There is also a problem that the lateral rigidity cannot be increased.
[0008]
Accordingly, an object of the present invention is to cause the driving force of the driving means to act on each connecting portion of the driving means and the linear motion guiding means of the XYθ table in a balanced manner.
[0009]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention supports a movable platen arranged in an XY plane expressed by an XY orthogonal coordinate system on a fixed platen via a thrust bearing, on the fixed platen side. , At least two first driving means that expand and contract in the same direction in the XY plane group parallel to the XY plane, and at least one second driving means that also expands and contracts in the direction orthogonal to the first driving means in the XY plane group. A drive means is attached, and on the movable platen side, a linear motion guide means connected to each of the drive means and having an engaging portion capable of linear guidance in the XY plane group is attached, and the movable plate is placed in the XY plane. In the XYθ table, which is rotatably connected to the fixed plate so that the movable plate can be moved in the X direction, the Y direction, and the θ direction which is the rotational direction in the XY plane, the at least two first drive means; Each linear motion guide to be connected A configuration in which an inclination angle is provided between the linear guide directions of the means is employed.
[0010]
That is, even when only the first or second driving means is driven by providing an inclination angle between the linear guide directions of each linear guide means connected to at least two first driving means. The driving force is always applied to one connecting portion of each linear guide means having the inclination angle, and at least two connecting portions are connected to the connecting portion connected to the driving means for supplying the driving force. The driving force acts on the part in a well-balanced manner.
[0011]
By providing each connecting portion between the drive means and the linear motion guide means outside the movable plate in the XY plane, the height dimension of the XYθ table can be designed compactly.
[0012]
By directing the linear guide directions of the linear motion guide means connected to the at least one first and second drive means in directions orthogonal to each other, these linear guide directions are oriented in the orthogonal direction. The amount of expansion and contraction of the first and second driving means connected to each linear motion guide means corresponds to the amount of movement of the movable board in two orthogonal directions, and the parallel movement of the movable board in each direction. The amount can be adjusted easily.
[0013]
By connecting each linear motion guide means whose linear guide directions are orthogonal to each other to the movable plate so as to be integrally rotatable, it is possible to reduce the number of parts by reducing the number of rotatable connecting portions. .
[0014]
The at least two first drive means are attached to opposite sides with respect to the center of the movable platen, and the inclination angle between the linear guide directions of the linear motion guide means connected to each of the drive means, By forming symmetrically with respect to the center of the movable platen, the respective expansion / contraction amounts of the first drive means connected to the two linear motion guide means having these symmetrical inclination angles are in two orthogonal directions. Therefore, it is possible to easily adjust the amount of parallel movement of the movable plate.
[0015]
By providing the at least one linear motion guiding means with a pair of parallel engaging portions capable of linear guidance, the engagement portions of the linear motion guiding means with respect to one connecting portion are provided at two locations. The driving force of the driving means that acts on the engaging portion can be reduced.
[0016]
Rolling surfaces are provided on the upper and lower surfaces of the fixed platen, and rolling surfaces are provided on the movable plate to face the respective rolling surfaces, respectively, between the opposed fixed plate and each rolling surface of the movable platen. By interposing a thrust rolling bearing, the rigidity of the XYθ table can be increased in both the vertical and horizontal directions.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 and 2 show a first embodiment. As shown in FIG. 1, this XYθ table supports a movable platen 1 arranged in a horizontal XY plane expressed by an XY orthogonal coordinate system on a fixed platen 3 via a thrust rolling bearing 2, On the fixed platen 3 side, two electric linear actuators 4a and 4b that expand and contract in the Y direction as the first driving means and one electric linear actuator 5 that expands and contracts in the X direction as the second driving means are attached, Three linear guides 6a, 6b, 7 which are linear motion guide means in a horizontal plane are attached to the movable platen 1 side.
[0018]
Each of the linear actuators 4a, 4b, and 5 is attached to the side surface of the stationary platen 3 with a bracket 8, and each of the linear guides 6a, 6b, and 7 is attached to a base metal fitting 9 that protrudes outside the movable platen 1, respectively. The linear actuators 4a, 4b, and 5 and the linear guides 6a, 6b, and 7 are connected to the outside of the movable platen 1, respectively.
[0019]
Each of the linear guides 6a, 6b, and 7 includes a guide portion 10 and a slide portion 11 that are slidably engaged with each other, and each slide portion 11 is rotatable with each linear actuator 4a, 4b, and 5 by pin coupling. It is connected. Therefore, the movable platen 1 can be moved in the X direction, the Y direction, and the θ direction by expanding and contracting each of the linear actuators 4a, 4b, and 5.
[0020]
The guiding directions of the two linear guides 6a, 7 connected to the linear actuators 4a, 5 as the first and second driving means are directed in directions orthogonal to each other. Therefore, the amount of expansion / contraction of the linear actuator 4a that expands / contracts in the Y direction and the amount of expansion / contraction of the linear actuator 5 that expands / contracts in the X direction easily correspond to the desired amount of movement of the movable platen 1 in the Y direction and X direction, respectively. be able to.
[0021]
Further, the guide direction of the linear guide 6b connected to the linear actuator 4b, which is another first driving means, is directed to a direction inclined by 45 ° with respect to the linear guide 6a. Therefore, when only the linear actuator 4a or 5 is driven, it is necessary to drive at least the connecting portion of the driving means for supplying these driving forces and the connecting portion between the linear guide 6b inclined at 45 ° and the linear actuator 4b. When force is applied and only the linear actuator 4b is driven, at least the connecting portion of the linear actuator 4b and the connecting portion of the linear guide 6a and the linear actuator 4a inclined at 45 ° relative to the linear guide 6b must be used. Driving force acts.
[0022]
As shown in FIGS. 2A and 2B, a through hole 12 is provided in the central portion of the fixed platen 3, and on the lower surface side of the movable platen 1, a thrust rolling bearing 13 is attached to the lower surface of the fixed platen 3. A sandwiching plate 14 that is sandwiched therebetween is connected by a connecting member 15 that is passed through the through hole 12. Rolling surfaces for the respective thrust rolling bearings 2 and 13 are provided on the upper and lower surfaces of the stationary platen 3, the lower surface of the movable platen 1, and the upper surface of the holding plate 14, respectively. Therefore, the XYθ table moves while the movable platen 1 holds the fixed platen 3 from above and below, so that high rigidity can be ensured in both the vertical and horizontal directions. The moving range of the movable platen 1 is set by the interval between the through hole 12 of the fixed platen 3 and the connecting member 15.
[0023]
FIG. 3 shows a second embodiment. In this XYθ table, a linear actuator 4a that is one of first driving means that expands and contracts in directions orthogonal to each other and a linear actuator 5 that is a second driving means are directed to the same corner portion of the fixed platen 3. The guide directions of the two linear guides 6a and 7 connected to the linear actuators 4a and 5 are oriented in directions orthogonal to each other, and are integrally attached to the L-shaped base metal fitting 9a.
[0024]
The movable platen 1 is provided with an arm member 16 projecting toward the corner of the fixed platen 3 where the base metal fitting 9a is located. The movable platen 1 is pin-coupled to the base metal fitting 9a by the arm member 16. The slide portions 11 of the respective linear guides 6a and 7 are directly connected to the respective linear actuators 4a and 5 irrespective of pin connection. Therefore, in this embodiment, the number of connecting portions for pin coupling is one less than in the first embodiment. Since the other portions are the same as those in the first embodiment, the same reference numerals as those in FIG. 1 are used.
[0025]
Similarly to the first embodiment, when driving only the linear actuator 4a or 5, this XYθ table also includes a connecting portion for driving means for supplying these driving forces, a linear guide 6b, and a linear actuator 4b. When driving only the linear actuator 4b, the driving force always acts on the connecting portion of the linear actuator 4b and the connecting portion of the linear guide 6a and the linear actuator 4a. To do.
[0026]
4 and 5 show a third embodiment. This XYθ table has two linear actuators 4a and 4b, which are first drive means extending and contracting in the Y direction, and the directions of the linear guides 6a and 6b connected to the left and right sides of the movable platen 1, respectively. The movable platen 1 is symmetrical with respect to the center line in the Y direction and is inclined in the opposite direction. The guide direction of the linear guide 7 connected to the linear actuator 5 which is the second drive means that expands and contracts in the X direction is directed in the Y direction.
[0027]
Each of the linear guides 6a, 6b, and 7 has a pair of parallel guide portions 10 attached to the two base metal fittings 9b and 9c, respectively, and the slide portion 11 is connected to each of the parallel guide portions 10 and two places. Are slidably engaged with each other and are respectively pin-coupled to the respective linear actuators 4a, 4b and 5 so as to be freely rotatable. These coupling portions are provided on the lower surface side of the slide portion 11 so as to form two layers on the upper and lower sides in order to achieve a compact design.
[0028]
Therefore, in this embodiment, the driving force acting on the engaging portions of the linear guides 6a, 6b, and 7 is reduced, and play at the engaging portions can be reduced. Since other parts are the same as those in the first embodiment, they are denoted by the same reference numerals as those in FIGS.
[0029]
In each of the embodiments described above, the movable platen is of a type that sandwiches the upper and lower surfaces of the fixed platen, and the movable platen is moved by two first driving means and one second driving means. The XYθ table according to the invention can be of a type in which the movable platen is supported only by the upper surface of the fixed platen, and the number of driving means can be further increased. The electric linear actuator as the driving means is driven using a stepping motor, a servo motor, a linear motor, or the like.
[0030]
【The invention's effect】
As described above, the XYθ table according to the present invention has an inclination angle between the linear guide directions of the linear motion guide means connected to at least two first drive means, and only the first or second drive means. Even in the case of driving the connecting portion, the connecting portion is connected to the driving means for supplying the driving force so that the driving force always acts on one connecting portion of each linear motion guide means having the inclination angle. In addition, since a driving force is applied to at least two connecting portions in a balanced manner, a large moment load is not generated on the movable plate, and the movable plate can be moved smoothly and positioned accurately. At the same time, the lateral rigidity of the XYθ table can be increased without hindrance.
[Brief description of the drawings]
1 is a partially cutaway plan view showing an XYθ table of the first embodiment. FIG. 2a is a side view in the X direction of FIG. 1, and b is a longitudinal sectional view in the Y direction of FIG. FIG. 4 is a plan view showing an XYθ table according to a second embodiment. FIG. 5 is a rear view of FIG. 4. FIG. 6 is a partially cutaway view showing a conventional XYθ table. Notched plan view [Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Movable board 2 Thrust rolling bearing 3 Fixed board 4a, 4b, 5 Linear actuator 6a, 6b, 7 Linear guide 8 Bracket 9, 9a, 9b, 9c Base metal fitting 10 Guide part 11 Slide part 12 Through-hole 13 Thrust rolling bearing 14 Clamping Plate 15 Connecting member 16 Arm member

Claims (7)

The movable platen arranged in the XY plane expressed in the XY rectangular coordinate system is supported on the fixed platen via the thrust bearing, and the same is mutually within the XY plane group parallel to the XY plane on the fixed platen side. At least two first driving means that extend and contract in the direction and at least one second driving means that extends and contracts in the direction orthogonal to the first driving means in the XY plane group are attached, A linear motion guide means connected to each drive means and having an engaging portion that can linearly guide in the XY plane group is attached, and the movable plate is connected to the fixed plate so as to be rotatable in the XY plane. In an XYθ table in which the panel can be moved in the X direction, the Y direction, and the θ direction that is the rotational direction in the XY plane, between the linear guide directions of the linear motion guide means connected to the at least two first drive means. With a tilt angle An XYθ table characterized by 2. The XYθ table according to claim 1, wherein a connecting portion between each driving unit and each linear guide unit is provided outside a movable plate in the XY plane. 3. The XYθ table according to claim 1, wherein the linear guide directions of the linear motion guide means connected to the at least one first drive means and the second drive means are oriented in directions orthogonal to each other. The XYθ table according to claim 3, wherein each linear motion guide means in which the linear guide directions are orthogonal to each other is connected to the movable plate so as to be integrally rotatable. The at least two first drive means are attached to opposite sides with respect to the center of the movable platen, and the inclination angle between the linear guide directions of the linear motion guide means connected to each of the drive means, The XYθ table according to claim 1, wherein the XYθ table is formed symmetrically with respect to the center of the movable platen. 6. The XYθ table according to claim 1, wherein the at least one linear motion guide means has a pair of parallel engaging portions capable of linear guidance. Rolling surfaces are provided on both upper and lower surfaces of the fixed platen, and rolling surfaces are provided on the movable platen so as to face the respective rolling surfaces, respectively, and between the opposed fixed platen and the respective rolling surfaces of the movable platen, respectively. The XYθ table according to any one of claims 1 to 6, wherein a thrust rolling bearing is interposed.

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