JP2001002213A - Floating unit and positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a floating unit that helps cleanliness improvement through suppressed generation of dust and that is excellent in durability and easy to miniaturize and thin. SOLUTION: An immovable board 23 carries thereon hard balls 24, upon which a movable board 25 is superposed. The hard balls 24 ensure smooth movement of the movable board 25 in separated relation to the immovable board 23. The immovable board 23 has a permanent magnet 29 fixed to its upper surface, and the movable board 25 has a permanent magnet 30 fixed to its undersurface. The permanent magnets 29 and 30 are in a spaced or noncontact relation and exert magnetic attraction on each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a floating unit and a positioning device. The floating unit used in the positioning device of the present invention supports a work with a movable portion, and supports the work with the movable portion such that the work can freely move and rotate on a straight line, on a curved line, or in a plane.

[0002]

2. Description of the Related Art There are positioning devices used for positioning products, components, and the like in a process of manufacturing, transporting, and assembling products such as a liquid crystal display device and a printed circuit board, and various components. FIG. 1 shows a conventional positioning device 1 used for such an application, and FIG. 2 shows a conventional floating unit 2 used for the positioning device 1.

In the conventional floating unit 2, as shown in FIG. 2, an annular frame 5 having an annular shape is horizontally supported by three support columns 4 erected on a fixed board 3. The movable part 6 is placed on the fixed board 3 so as to be inserted into the frame 5. A ball bearing 7 is held on the lower surface of the movable portion 6, and the movable portion 6 can be smoothly moved on the fixed platen 3 by the ball bearing 7. One toggle-shaped spring 8 is stretched between the annular frame 5 and the movable portion 6. When no external force is applied to the movable portion 6, the movable portion 6 exerts the elastic return force of the spring 8. To return to the center in the annular frame 5.

[0004] As shown in FIG.
Two floating units 2, and a position corrector 9 is provided near each floating unit 2.
Is provided. The position corrector 9 is provided with two positioning posts 11 on the upper surface of a plate 10 that moves diagonally toward the positioning center.
0 moves synchronously by the same distance.

When the work W is supplied and mounted on the floating unit 2 as shown in FIG. 1, the work W is moved by the floating unit 2 with a small external force. When the plate 10 is driven and moves toward the positioning center, the positioning post 11 abuts on the lower corner of the work W, and the position of the work W is forcibly corrected by the positioning post 11, so that the center of the work W and the positioning center can be moved. Are positioned so as to match.

[0006]

However, in the floating unit 2 as shown in FIG. 2, since the spring 8 is used as the centripetal force generating means, dust is generated due to the rubbing of the seat surface of the spring 8 and the liquid crystal display. In a precise work process in a clean room as in the manufacturing process of (1), there is a possibility that the cleanliness in the clean room may be reduced due to dust generation. Also, the spring 8
In this case, a problem of durability occurs due to elastic fatigue during repeated use. Further, the size of the floating unit 2 using the spring 8 is large, and it is difficult to reduce the size and thickness of the unit.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned technical problems. An object of the present invention is to reduce dust, generate high cleanliness, excel in durability, reduce the size, and reduce the size. An object of the present invention is to provide a floating unit that can be easily made thin. Another object of the present invention is to provide a positioning device that generates a small amount of dust and has high cleanliness.

[0008]

According to a first aspect of the present invention, in the floating device, the movable portion is opposed to the fixed portion, and a rolling member that smoothly rolls is interposed between the movable portion and the fixed portion. This allows the movable part to move with respect to the fixed part, separates the movable part and the fixed part, and returns the movable part to the predetermined position of the fixed part when the movable part is displaced from the predetermined position of the fixed part. A means for generating a centripetal force acting in a non-contact manner so as to perform the non-contact is provided in the movable part and the fixed part. Here, the rolling member is a member that smoothly moves the movable member on a line or in a plane, such as a cylindrical roller or a hard sphere. Further, as the non-contact centripetal force generating means, a magnetic attraction force using a permanent magnet or an electromagnet, an electrostatic attraction force, or the like is used.

In the floating unit according to the first aspect, the movable member can be moved relative to the fixed portion by interposing the rolling member, and the movable portion and the fixed portion are separated from each other. , Even if the movable part supporting the work moves, there is no wear between the movable part and the fixed part,
Difficult to generate dust. Furthermore, since the movable part is returned to the original position by the centripetal force generating means that works in a non-contact manner,
Unlike the conventional example using a spring, dust is not generated by the centripetal force generating means.

Therefore, the floating unit according to the first aspect is less likely to generate dust, has a high degree of cleanness, and can be used even in a place where a clean degree is required, such as a clean room.

Further, since the centripetal force generating means utilizing the magnetic attraction force or the electrostatic attraction force is used, there is no problem of elastic fatigue unlike a spring, and the durability is high. Furthermore, compared to a floating system using a spring, the size and thickness can be reduced.

According to a second aspect of the present invention, in the floating unit according to the first aspect, the centripetal force generating means includes a permanent magnet provided on a movable portion and a permanent magnet or a ferromagnetic material provided on a fixed portion. So,
It is characterized in that they are provided with a gap therebetween.

According to a third aspect of the present invention, in the floating unit according to the first aspect, the centripetal force generating means is a permanent magnet provided in a movable portion or a ferromagnetic material and a permanent magnet provided in a fixed portion. So,
It is characterized in that they are provided with a gap therebetween.

In the floating unit according to the second or third aspect, since the permanent magnets are used as the centripetal force generating means or a permanent magnet and a ferromagnetic material, the centrifugal force is applied to the movable portion by a simple and inexpensive structure. Can be generated. Moreover, since there is no need to wire an electric cord as in the case of using an electromagnet or the case of using electrostatic attraction, the configuration can be simplified. It is also excellent in reducing the size and thickness of the floating unit.

According to a fourth aspect of the present invention, in the floating unit according to the first, second or third aspect, the rolling member is a hard ball, and the centripetal force generating means of the movable portion is provided at a center of the movable portion. It is characterized by being provided.

In the floating unit according to the fourth aspect, since a hard ball is used as the rolling member, the movable part can not only move in parallel to the fixed part but also rotate. Therefore, not only can the position of the work placed on the movable part be corrected, but also the angle of the work can be corrected. Further, since the centripetal force generating means of the movable part is provided at the center of the movable part, the movable part can be returned to the original position after the work is removed even if the movable part is rotating. In addition, since hard balls are used, there is no wear or deformation and stable rolling is possible.

According to a fifth aspect of the present invention, there is provided a positioning device, comprising: the floating unit according to the first, second, third or fourth aspect;
Position correction means for positioning a work placed on the floating unit at a predetermined position is provided.

Since the positioning device according to the fifth aspect includes the floating unit according to the first, second, third, or fourth aspect, it is possible to prevent the generation of dust and to increase the cleanliness. Therefore, it can be used as a positioning device in a clean room or the like.

[0019]

(First Embodiment) FIG. 3 is a schematic plan view showing a positioning device 21 according to one embodiment of the present invention, and FIGS. FIG. 3 is a partially cutaway plan view and a sectional view showing a floating unit 22 used. First, the structure of the floating unit 22 will be described.

The floating unit 22 includes a fixed board 2
3, a plurality of hard balls 24 are placed on the hard balls 24, and a disc-shaped movable plate 25 is superimposed on the hard balls 24. The movable plate 25 is moved by the hard balls 24 so that the movable plate 25 does not contact the fixed plate 23. Are separated from the fixed platen 23, and the movable platen 25
Can be smoothly moved and rotated on the fixed platen 23 by the hard ball 24. The hard sphere 24 is rotatably held in an opening 27 of an annular retainer 26 so as not to fall apart, and is provided outside the movable platen 25 by a skirt 28 suspended from an outer peripheral edge of the movable platen 25. It is prevented from coming off.

At the center of the upper surface of the fixed board 23, a permanent magnet 29 is provided.
The permanent magnet 30 is also fixed to the center of the lower surface of the movable platen 25. The two permanent magnets 29 and 30 are separated from each other through a required gap so as to exert an attractive force on each other. It is opposed. The outer diameter of both permanent magnets 29 and 30 is smaller than the inner diameter of retainer 26. The fixed platen 23, the hard ball 24 and the movable platen 25
It is held so as not to be separated by the magnetic attraction force between 9 and 30. The gap between the permanent magnets 29 and 30 and the holder 26 is appropriately determined in consideration of the floating amount, the size of the positioning device 21, and the like. When a horizontal external force is applied to the movable platen 25, as shown in FIG. 5, the movable platen 25 can move against the magnetic attraction between the permanent magnets 29 and 30, and when the external force is removed. The movable platen 25 is returned to the original position by a centripetal force (magnetic attraction force) acting between the permanent magnets 29 and 30. Further, when an external force is applied, the movable platen 25 can be smoothly moved and rotated by the hard ball 24. The retainer 26 is a permanent magnet 2
A material that is not sucked by 9, 30 and has wear resistance (for example,
(Engineering plastics, etc.), and a ball bearing retainer can also be used.

The positioning device 21 shown in FIG.
(For example, four) floating units 22 and a plurality of position correctors 32 that push and position (center) the work W so as to sandwich the front and rear and both side surfaces of the work W. I have. The position corrector 32 causes the rod 34 to protrude by the drive actuator 33, and the work W is sandwiched by the tip of the rod 34 so that the center of the work W coincides with the center point of positioning. The present invention is not limited to the illustrated one, and for example, the same one as the position corrector used in the conventional example shown in FIG. 1 may be used.

A point C is a positioning center point at which the center of the workpiece W is to be positioned. The left and right opposing floating units 22 are arranged symmetrically with respect to the positioning center point C, and the right and left opposing position correctors 32 are also disposed. They are arranged symmetrically with respect to the positioning center point C. Similarly, the front and rear floating units 22 are arranged symmetrically with respect to the positioning center point C, and the front and rear facing position correctors 32 are also arranged symmetrically with respect to the positioning center point C. Furthermore, the left and right position correctors 32
Is driven so that the tip of the rod 34 is equidistant from the positioning center point C where the center of the workpiece W in the left-right direction is to be positioned. Similarly, front and rear position corrector 3
2 is also driven so that the tip of the rod 34 is equidistant from the positioning center point C where the center of the workpiece W in the front-rear direction is to be positioned.

Next, according to FIGS. 6 (a) (b) and 7 (c) (d),
The positioning operation by the positioning device 21 will be described.
However, the positioning in the front-back direction and the positioning in the left-right direction are
Since the same operation is performed at the same time, only the positioning in the left and right direction will be described. 6 (a) (b) and FIGS. 7 (c) (d), a position C indicates a positioning center point of the positioning device 21, G indicates a perpendicular passing through the center of the work W, and P indicates a floating unit 22. , The center of the movable platen 25, Q indicates the position of the center of the fixed platen 23.

When the workpiece W is not supplied to the positioning device 21, the center P of the movable platen 25 of each floating unit 22 is set to the center Q of the fixed platen 23, as shown in the standby state of FIG. Matches. AGV
FIG. 6B shows a state in which the work W is supplied to the positioning device 21 by an (unmanned traveling vehicle), a robot, or the like, and the work W is mounted on the movable platen 25. In this state, since no horizontal external force is applied to the floating unit 22, the movable platen 25 is located at the center of the fixed platen 23, and the center G of the work W is generally shifted from the positioning center C of the positioning device 21. ing.

Next, when the right and left position correctors 32 are driven to project the rods 34 from the left and right at equal distances, one of the rods 34 first strikes the side surface of the work W in accordance with the position shift state of the work W. Since the work W is smoothly moved by the floating unit 22, when the rod 34 in contact with the work W is further protruded, the work W is pushed by the rod 34 and moves right or left. When the other rod 34 also comes into contact with the side surface of the work W in this way, the work W cannot be moved while being sandwiched between the rods 34, and FIG.
As shown in (c), the center G of the work W is positioned at the center point C of positioning.
And the work W is positioned at the regular position.

During this time, the work W is positioned by the front and rear position corrector 32 in the front and rear direction as well as in the left and right direction. When the work W is a cassette, the cassette is positioned so that a robot or the like can easily take out the substrate stored in the cassette.

When a predetermined work is completed on the work W positioned as described above, each rod 3 of the position corrector 32 is
4 moves back to the original position, and the work W is carried out by an AGV, a robot, or the like. When the work W is carried out, FIG.
As shown in (d), the movable platen 25 of the floating unit 22 returns to the original position by the centripetal force between the permanent magnets 29 and 30 and enters a standby state.

As described above, the positioning device 21
Since the movable portion moves smoothly by the hard spheres 24, generation of dust is suppressed, and a skirt 28 is provided around the movable plate 25 to cover the retainer 26 and the hard spheres 24. It is possible to prevent the dust generated by the particles 26 and the hard balls 24 from scattering.

After the work W is removed, the movable platen 25
Since the centripetal force generating means for returning to the original position is a magnetic force and acts in a non-contact manner between the movable platen 25 and the fixed platen 23, there is no danger of dust being generated therefrom. Further, dust generated by the hard spheres 24 is trapped by the permanent magnets 29 and 30, and can be prevented from scattering around and lowering the cleanness of the clean room.

Also, a permanent magnet 2 is used instead of the spring.
By using the components 9 and 30, the structure of the floating unit 22 can be simplified and the cost can be reduced.

Further, the floating unit 22
Since the disk-shaped permanent magnets 29 and 30 are vertically opposed to each other, the effective area in which the magnetic field acts is wide, and the centering function is performed at the center of the center magnet where the magnetic field is strongest. Further, the space for installing the retainer 26 can be narrowed, the mechanism is simplified, and the floating unit 2 is installed.
2 can be made compact.

In the above-described embodiment, the work W is positioned in the front, rear, left and right. However, when only the left and right positioning is performed, for example, only the left and right position correctors are used as in a positioning device 41 shown in FIG. It is sufficient to provide 32. In this case, a cylindrical roller may be used as the rolling member instead of the hard ball 24 so that the movable portion can move only to the left and right.

In the above embodiment, a pair of permanent magnets is used as the centripetal force generating means, but one of them may be replaced with a ferromagnetic material. Further, an electromagnet may be used instead of the permanent magnet. Alternatively, an electrostatic attraction force between electrode plates charged to different polarities may be used. However, when an electromagnet or an electrostatic attraction force is used, the treatment of the electric cord is required, so that the configuration can be simplified by using the permanent magnet.

[0035]

According to the floating unit of the first aspect, the movable portion can be smoothly moved by the rolling member, and the movable portion is returned to the original position by the centripetal force generating means which works in a non-contact manner. Therefore, generation of dust can be suppressed. Therefore, it can be used even in a place where cleanliness is high and cleanliness is required, such as a clean room.

Further, since the centripetal force generating means utilizing the magnetic attraction force or the electrostatic attraction force is used, there is no problem of elastic fatigue unlike a spring, and the durability is high. Further, the size and thickness can be reduced as compared with a floating system using a spring.

According to the floating unit of the second or third aspect, since the permanent magnets are formed between the permanent magnets or the permanent magnet and the ferromagnetic material as the centripetal force generating means, the centripetal force is applied to the movable portion by a simple and inexpensive configuration. Can be generated. Moreover, since there is no need to wire an electric cord as in the case of using an electromagnet or the case of using electrostatic attraction, the configuration can be simplified. Further, the floating unit can be reduced in size and thickness.

According to the floating unit of the fourth aspect, since a hard ball is used as the rolling member, the movable portion can not only move in parallel to the fixed portion but also rotate. Therefore, not only can the position of the work placed on the movable part be corrected, but also the angle of the work can be corrected. Further, since the centripetal force generating means of the movable part is provided at the center of the movable part, the movable part can be returned to the original position after the work is removed even if the movable part is rotating.

According to the positioning device of the fifth aspect,
Dust can be hardly generated, and cleanliness can be increased. Therefore, it can be favorably used as a positioning device in a clean room or the like.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the structure of a conventional positioning device.

FIGS. 2A and 2B are a plan view and a partially broken front view showing a floating unit used in the positioning device of FIG.

FIG. 3 is a schematic plan view showing a positioning device according to an embodiment of the present invention.

FIGS. 4A and 4B are a partially broken plan view and a sectional view showing a floating unit used in the positioning device of the above.

FIG. 5 is a cross-sectional view showing a state where the movable platen of the floating unit is displaced from the center.

FIGS. 6A and 6B are views showing a step of positioning (centering) a work W by a positioning device.

7 (c) and (d) are continuation diagrams of FIG.

FIG. 8 is a schematic plan view showing a positioning device according to an embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 21 Positioning device 22 Floating unit 23 Fixed plate 24 Hard ball 25 Movable plate 29, 30 Permanent magnet 32 Position corrector 33 Drive actuator W Work

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H01L 21/68 H01L 21/68 G

Claims (5)

[Claims] 1. A movable part is opposed to a fixed part, and a rolling member that smoothly rolls is interposed between the movable part and the fixed part so that the movable part can move with respect to the fixed part. The movable means and the fixed part are separated from each other, and the means for generating a centripetal force acting in a non-contact manner so as to return the movable part toward the predetermined position of the fixed part when the movable part is displaced from the predetermined position of the fixed part is movable. A floating unit, wherein the floating unit is provided in a portion and a fixed portion. 2. The centripetal force generating means is a permanent magnet provided on a movable part and a permanent magnet or a ferromagnetic substance provided on a fixed part, and is provided with a gap therebetween. The floating unit according to claim 1. 3. The centripetal force generating means is a permanent magnet provided on a movable portion or a ferromagnetic material and a permanent magnet provided on a fixed portion, and is provided with a gap therebetween. The floating unit according to claim 1. 4. The floating member according to claim 1, wherein the rolling member is a hard sphere, and the centripetal force generating means of the movable portion is provided at a center of the movable portion. unit. 5. A positioning device comprising: the floating unit according to claim 1, 2, 3 or 4; and a position correcting means for positioning a work placed on the floating unit at a predetermined position.