Angle Adjustable Table

Abstract

To provide an angle adjustment table capable of suppressing lost motion and highly accurately positioning an object.SOLUTION: An angle adjustment table includes a positioning mechanism 15 for rotating a turntable 13 rotatably supported on a base 11 by a cross-roller bearing 17 to position the same at a target position. The positioning mechanism 15 includes: a bracket 31 which is supported on the base 11 and is linearly movable in the tangential direction of the turntable 13; a ball screw device 33 that linearly moves the bracket 31; a connection part 35 that is supported so as to be linearly movable in a direction orthogonal to the linear moving direction of the bracket 31 with respect to the bracket 31 and that connects the bracket 31 and an arm 23 of the turntable 13 and converts linear motion of the bracket 31 into rotational motion of the turntable 13; and a plate spring 91 that biases the bracket 31 and the turntable 13 in opposing directions in an intersection direction with the axis of the turntable 13.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an angle adjustable table. [Background technology]

[0002] An angle adjustment table, which rotates an object to place it at a target position, is equipped with a positioning mechanism that rotates the rotating table to position it.

[0003] Patent documents 1 to 3 show a positioning mechanism including a bracket that moves linearly in the tangential direction of the swivel table by a linear guide, and a connecting part that is provided between the arm of the swivel table and the bracket and transmits the linear motion of the bracket to the arm of the swivel table to convert it into rotational motion of the swivel table. Patent document 3 also discloses a structure of a connecting part in which a protruding piece erected on a nut of a ball screw device is supported by being clamped by a cam follower provided on the arm of the swivel table using a compression spring. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-221044 A [Patent Document 2] JP 2002-341076 A [Patent Document 3] JP 2000-238232 A Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, in the angle adjustment tables that rotate the swivel table as in the above Patent Documents 1 to 3, a large starting torque is required when rotating the swivel table. Therefore, if the rigidity of the connecting parts that make up the positioning mechanism is insufficient, lost motion may occur between the arm and bracket of the swivel table when the rotation direction of the swivel table is reversed, which may reduce the positioning accuracy.

[0006] SUMMARY OF THE PRESENT DISCLOSURE An object of the present invention is to provide an angle adjustment table that is capable of suppressing lost motion and positioning an object with high accuracy. [Means for solving the problem]

[0007] The present invention comprises the following configurations. With the base, a rotating table rotatably supported by a bearing on the base; a positioning mechanism that rotates the turntable relative to the base and positions it at a target position; An angle adjustment table comprising: The positioning mechanism includes: a bracket supported by the base and capable of linear movement in a tangential direction of the rotating table; A drive unit that moves the bracket linearly; a connecting portion that is supported on the bracket so as to be linearly movable in a direction perpendicular to the linear movement direction of the bracket, and that connects the bracket and the rotating table to convert the linear movement of the bracket into a rotational movement of the rotating table; a biasing member that biases the bracket and the rotating table in opposite directions in a direction intersecting with an axis of the rotating table; Equipped with Angle adjustable table. Effect of the Invention

[0008] According to the angle adjustment table of the present invention, lost motion can be suppressed and an object can be positioned with high accuracy. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a plan view of the angle adjustment table according to the embodiment. [Diagram 2] 2 is a view of the angle adjustment table according to the present embodiment taken along the line A in FIG. 1. [Diagram 3] 2 is a cross-sectional view taken along the line B in FIG. 1 showing a portion of the angle adjustment table according to the present embodiment. [Figure 4] FIG. 4 is a front view of a connecting portion that constitutes the positioning mechanism. [Diagram 5] 13 is a side view showing a cross section of a part of a connecting portion that constitutes the positioning mechanism. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Fig. 1 is a plan view of an angle adjustment table 100 according to this embodiment. Fig. 2 is a view of the angle adjustment table 100 according to this embodiment as seen from an arrow A in Fig. 1. Fig. 3 is a cross-sectional view of a portion of the angle adjustment table 100 according to this embodiment as seen from an arrow B in Fig. 1.

[0011] 1 to 3, the angle adjustment table 100 according to this embodiment includes a base 11, a swivel table 13, and a positioning mechanism 15. The swivel table 13 is rotatably supported on the base 11, and the positioning mechanism 15 rotates and positions the swivel table 13 on the base 11.

[0012] In the angle adjustment table 100, an object such as a semiconductor wafer is placed on the upper part of the swivel table 13. In this state, the swivel table 13 is rotated by the positioning mechanism 15, whereby the object placed on the swivel table 13 is positioned at an inspection position or a processing position.

[0013] A cross roller bearing (bearing) 17 is provided between the base 11 and the swivel table 13 , and the swivel table 13 is supported on the base 11 by the cross roller bearing 17 so as to be rotatable thereon.

[0014] The base 11 has a protruding portion 11a that protrudes laterally from one side thereof, and a positioning mechanism 15 is provided on the protruding portion 11a of the base 11. The swivel table 13 has an arm 23 that extends from the outer periphery toward the positioning mechanism 15 side.

[0015] The positioning mechanism 15 includes a bracket 31, a ball screw device (drive unit) 33, and a connecting unit .

[0016] The bracket 31 is supported by a linear guide 41 on the overhanging portion 11a of the base 11. The linear guide 41 has a guide rail 43 fixed to the overhanging portion 11a of the base 11 along a tangential direction perpendicular to the radial direction of the swivel table 13, and a slider 45 fixed to the bracket 31 and provided so as to be movable relative to the guide rail 43. A plurality of rolling elements (not shown) are rotatably held on the slider 45 at a portion facing the guide rail 43, and the rolling of the rolling elements allows linear motion relative to the guide rail 43 with low friction. The bracket 31 is supported by the linear guide 41 so as to be linearly movable in the tangential direction of the swivel table 13.

[0017] The ball screw device 33 is composed of a motor 51 supported on the protruding portion 11a of the base 11, a screw shaft 53 rotated by the motor 51, and a nut 55 fixed to the bracket 31 and into which the screw shaft 53 is screwed.

[0018] In the ball screw device 33, balls (not shown) are freely rollably disposed in a spiral rolling space (not shown) formed by a spiral ball groove formed on the outer circumferential surface of the screw shaft 53 and a spiral ball groove formed on the inner circumferential surface of the nut 55. In the ball screw device 33, when the screw shaft 53 is rotated by the motor 51, the rotational motion of the screw shaft 53 is transmitted to a plurality of balls, which circulate along the spiral rolling space, causing the nut 55 to reciprocate along the screw shaft 53. As a result, the bracket 31 supported on the protruding portion 11a of the base 11 by the linear guide 41 is linearly moved in the tangential direction of the swivel table 13.

[0019] Fig. 4 is a front view of a connecting portion 35 constituting the positioning mechanism 15. Fig. 5 is a side view in which a part of the connecting portion 35 constituting the positioning mechanism 15 is viewed in cross section.

[0020] 4 and 5, the connecting portion 35 is provided between the bracket 31 and the arm 23 of the swivel table 13, and connects the bracket 31 and the arm 23. The connecting portion 35 includes a linear guide 71, a plate member 73, a rotating shaft 75, an annular housing 77, and a rolling bearing 79.

[0021] The plate member 73 is supported by the bracket 31 via the linear guide 71. The linear guide 71 has a guide rail 81 fixed to the bracket 31 along a direction perpendicular to the movement direction of the bracket 31, and a slider 83 fixed to the plate member 73 and provided movable relative to the guide rail 81. The slider 83 has a plurality of rolling elements (not shown) rollably held in a portion facing the guide rail 81, and the rolling elements roll to enable linear motion relative to the guide rail 81 with low friction. The plate member 73 is supported so as to be linearly movable relative to the bracket 31 in a direction perpendicular to the movement direction of the bracket 31.

[0022] The rotating shaft 75 is provided upright on the plate member 73 and is inserted into an annular housing 77. The annular housing 77 is fixed to the arm 23 of the swivel table 13. A rolling bearing 79 is provided between the rotating shaft 75 and the annular housing 77, and the rotating shaft 75 is rotatable relative to the annular housing 77 by the rolling bearing 79. This allows the rotating shaft 75 to rotate relative to the arm 23 of the swivel table 13.

[0023] The connecting portion 35 has a leaf spring (biasing member) 91. The leaf spring 91 is made of a metal material such as carbon steel, stainless steel, a nickel alloy, or a titanium alloy, and is formed in a plate shape. The lower end portion of the leaf spring 91 is connected to the end surface 31a of the bracket 31, and the upper end portion is connected to the end surface 23a of the arm 23. The leaf spring 91 is formed so that the width of the middle portion is narrower than that of both end portions.

[0024] In the angle adjustment table 100 configured as above, when the motor 51 of the ball screw device 33 is driven to rotate the screw shaft 53, the nut 55 fixed to the bracket 31 moves back and forth along the screw shaft 53. As a result, the bracket 31 supported on the protruding portion 11a of the base 11 by the linear guide 41 moves linearly along the tangential direction of the swivel table 13. Then, this linear motion of the bracket 31 is transmitted as a rotational motion that swings the arm 23 of the swivel table 13 via the rotation shaft 75 of the connecting portion 35. As a result, the swivel table 13 on which the object is mounted rotates, and the angle of the object on the swivel table 13 is adjusted and positioned at the target position.

[0025] Furthermore, when the arm 23 is swung, the rotating shaft 75 moves along the moving direction of the bracket 31, and also displaces slightly in a direction perpendicular to the moving direction of the bracket 31. This displacement is absorbed by the linear movement of the plate member 73 in the direction perpendicular to the moving direction of the bracket 31 by the linear guide 71. As a result, in the angle adjustment table 100, the swivel table 13 can be rotated without applying excessive force to the bracket 31, the rotating shaft 75, the arm 23, etc.

[0026] In the angle adjustment table 100, the swivel table 13 is set to an origin position O when the end surface 23a of the arm 23 of the swivel table 13 and the end surface 31a of the bracket 31 are parallel in a plan view (see FIG. 1). The swivel table 13 at the origin position O is rotated in a clockwise direction (the direction of the arrow α in FIG. 1) or counterclockwise direction (the direction of the arrow β in FIG. 1) in a plan view by the ball screw device 33 being driven.

[0027] Incidentally, since a large and heavy object is mounted on the swivel table 13, a cross roller bearing 17 is used as a bearing for supporting the swivel table 13 on the base 11. This cross roller bearing 17 has a large sliding resistance, so a large starting torque is required when rotating the swivel table 13. For this reason, if the rigidity of the connecting part 35 is low, there is a risk that a slight inclination will occur in the rotation shaft 75 of the connecting part 35, and this inclination of the rotation shaft 75 will change when the rotation direction of the swivel table 13 is reversed.

[0028] The angle adjustment table 100 according to this embodiment includes a leaf spring 91 connected to an end surface 31a of the bracket 31 that is linearly moved by the ball screw device 33 and an end surface 23a of the arm 23 of the swivel table 13 that is rotationally moved. When the swivel table 13 is rotated clockwise (α direction) or counterclockwise (β direction) from the origin position O, this leaf spring 91 elastically deforms so as to be twisted slightly in association with the rotation of the swivel table 13. Then, an urging force formed by a reaction force of the elastic deformation of this leaf spring 91 acts on the arm 23 of the swivel table 13 and the bracket 31.

[0029] The biasing force from the leaf spring 91 is applied so as to bias the bracket 31 and the arm 23 of the rotating table 13 in mutually opposite directions in a direction intersecting the axis of the rotating table 13. The biasing force from the leaf spring 91 always acts in one direction while the rotating table 13 rotates clockwise (α direction) from the origin position O to the target position and while it rotates counterclockwise (β direction) from the target position to the origin position O in a plan view. The biasing force from the leaf spring 91 always acts in the other direction while the rotating table 13 rotates counterclockwise (β direction) from the origin position O to the target position and while it rotates clockwise (α direction) from the target position to the origin position O in a plan view. In other words, the biasing force from the leaf spring 91 reverses its acting direction at the origin position O of the rotating table 13.

[0030] Therefore, when the rotation direction of the swivel table 13 is reversed from clockwise (α direction) to counterclockwise (β direction) at a position other than the origin position O, or when the rotation direction of the swivel table 13 is reversed from counterclockwise (β direction) to clockwise (α direction), the direction of the sliding resistance of the cross roller bearing 17 is reversed, but the direction of the biasing force applied from the leaf spring 91 does not change. In other words, regardless of the reversal of the direction of the sliding resistance in the cross roller bearing 17, the biasing force of the leaf spring 91 is applied in the same direction. For this reason, the biasing force from the leaf spring 91 suppresses lost motion caused by the change in the inclination of the rotation shaft 75 of the connecting part 35 accompanying the reversal of the direction of the sliding resistance.

[0031] As described above, according to the angle adjustment table 100 of this embodiment, when the swivel table 13 is rotated, the leaf spring 91 between the bracket 31, which moves linearly, and the arm 23 of the swivel table 13, which moves rotationally, is twisted and elastically deformed. As a result, a biasing force consisting of a reaction force of the elastically deforming leaf spring 91 is applied as a preload between the bracket 31 and the swivel table 13. Therefore, it is possible to reduce lost motion in the connecting part 35 that connects the bracket 31 and the swivel table 13, and it is possible to improve the positioning accuracy of the swivel table 13.

[0032] Moreover, since the structure is simple in that the leaf spring 91 connected to the arm 23 and the bracket 31 is provided as a biasing member, lost motion can be reduced at low cost, and the positioning accuracy of the swivel table 13 can be improved.

[0033] In the above embodiment, the biasing member made of the leaf spring 91 is provided, but the biasing member that applies a biasing force to the arm 23 and the bracket 31 is not limited to the leaf spring 91.

[0034] In the above embodiment, the bracket 31 is moved by the ball screw device 33. However, the drive unit for moving the bracket 31 is not limited to the ball screw device 33, and may be, for example, a linear actuator.

[0035] As such, the present invention is not limited to the above-described embodiments, and the present invention also contemplates mutual combinations of the various components of the embodiments, as well as modifications and applications by those skilled in the art based on the descriptions in the specification and well-known technologies, and these are included in the scope of protection sought.

[0036] As described above, the present specification discloses the following: (1) A base; a rotating table rotatably supported by a bearing on the base; a positioning mechanism that rotates the turntable relative to the base and positions it at a target position; An angle adjustment table comprising: The positioning mechanism includes: a bracket supported by the base and capable of linear movement in a tangential direction of the rotating table; A drive unit that moves the bracket linearly; a connecting portion that is supported on the bracket so as to be linearly movable in a direction perpendicular to the linear movement direction of the bracket, and that connects the bracket and the rotating table to convert the linear movement of the bracket into a rotational movement of the rotating table; a biasing member that biases the bracket and the rotating table in opposite directions in a direction intersecting with an axis of the rotating table; An angle adjustment table. The angle adjustment table having this configuration includes a biasing member that biases the bracket and the swivel table in opposite directions intersecting with the axis of the swivel table, whereby the biasing force of the biasing member is applied between the bracket and the swivel table as a preload, thereby reducing lost motion at the connection portion that connects the bracket and the swivel table and improving the positioning accuracy of the swivel table.

[0037] (2) The biasing member is made of a leaf spring, The angle adjustment table according to (1), wherein one end of the leaf spring is connected to an arm extending from the outer periphery of the swivel table and the other end is connected to the bracket. With this angle adjustment table, when the swivel table is rotated, the leaf spring between the bracket that moves linearly and the arm of the swivel table that moves rotationally is twisted and elastically deformed. This causes a biasing force formed by the reaction force of the elastically deforming leaf spring to be applied as a preload between the bracket and the swivel table. This makes it possible to reduce lost motion in the connection part that connects the bracket and the swivel table, and improve the positioning accuracy of the swivel table. Furthermore, since the structure is simple, in which a leaf spring connected to the arm and bracket is provided as a biasing member, lost motion can be reduced at low cost, and the positioning accuracy of the swivel table can be improved. [Explanation of symbols]

[0038] 11. Base 13 Swivel table 15 Positioning mechanism 17 Cross roller bearing (bearing) 23 Arm 31 Bracket 33 Ball screw device (drive unit) 35 Connecting part 91 Leaf spring (biasing member) 100 Angle Adjustable Table

Claims

1. With the base, a rotating table rotatably supported by a bearing on the base; a positioning mechanism that rotates the turntable relative to the base and positions it at a target position; An angle adjustment table comprising: The positioning mechanism includes: a bracket supported by the base and capable of linear movement in a tangential direction of the rotating table; A drive unit that moves the bracket linearly; a connecting portion that is supported on the bracket so as to be linearly movable in a direction perpendicular to the linear movement direction of the bracket, and that connects the bracket and the rotating table to convert the linear movement of the bracket into a rotational movement of the rotating table; a biasing member that biases the bracket and the rotating table in opposite directions in a direction intersecting with an axis of the rotating table; Equipped with Angle adjustable table.

2. The biasing member is a leaf spring. The leaf spring has one end connected to an arm extending from the outer periphery of the rotating table, and the other end connected to the bracket. The angle adjustment table according to claim 1 .

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