JPH0839463A - Transfer device - Google Patents

Abstract

(57) [Abstract] [Object] An object of the present invention is to provide a carrier device capable of accurately positioning a holder holding a semiconductor wafer. A turntable 22 is rotatably driven by a table motor 26, and a pair of first links 23a and 23b whose one end is rotatably supported by the turntable.
An adjusting mechanism 53 provided on the turntable for adjusting a distance between one ends of the pair of first links, and a pair of second links 28 having one end rotatably connected to the other end of the first link.
a and 28b, a holder 31 having a holding portion 31a that is rotatably connected to the other end of the second link and holds the semiconductor wafer U, and a link motor 25 that rotationally drives one of the first links. A main gear 4 provided at a connecting portion between the first link and the second link and transmitting the rotation of one of the first links driven by the link motor to the second link.
3, 44 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carrying device for carrying and positioning an article to be carried such as a semiconductor wafer.

[0002]

2. Description of the Related Art For example, in a semiconductor device manufacturing process, a transfer device is installed to transfer the semiconductor wafer between the respective processes. Since this transfer device transfers the semiconductor wafer processed by the processing device in the downstream process to the processing device in the upstream process, the semiconductor wafer is transferred and positioned not only in the linear direction but also in the rotation direction. However, high positioning accuracy may be required.

Conventionally, as an apparatus for carrying out such conveyance and positioning of a semiconductor wafer, there is known one disclosed in JP-A-4-30447. This apparatus has a turntable 1 as shown in FIG. A driven gear 2 is provided at the lower end of the turntable 1. A drive gear 3 meshes with the driven gear 2. The drive gear 3 is rotationally driven by the first motor 4. As a result, the turntable 1 is rotationally driven in the direction indicated by the arrow.

One end of each pair of two sets of first links 5a, 5b is rotatably connected to the upper surface of the turntable 1. One of the links 5a and 5b of each set is connected to a drive shaft 6a which is rotationally driven by a second motor 6, respectively.

The other ends of the first links 5a and 5b of each set are pivotally attached to the connecting plate 7. One end of each of the pair of second links 8a and 8b is pivotally attached to each connecting plate 7. Further, the connecting plate 7 is provided with a pair of synchronous gears 9 that mesh with each other.

A holding body 10 is pivotally attached to the other ends of the pair of second links 8a and 8b, respectively. A holding portion 10 a for holding a semiconductor wafer is formed on these holding bodies 10.

In such a structure, the second motor 6
Thus, if one of the pair of first links 5a, 5b is rotationally driven, the rotation is transmitted to the second links 8a, 8b via the synchronous gear 9, respectively. 8b and the first links 5a, 5b symmetrically rotate while maintaining a parallel state. as a result,
A holder 10 pivotally attached to the other ends of the second links 8a and 8b.
Will be driven linearly in the front-back direction indicated by the arrow.

If the first motor 4 is actuated to rotate the drive gear 3 and the driven gear 2 is interlocked with the rotation of the first gear 4, the turntable 1 rotates, so that the holder 10 is held.
Positioning in the direction of rotation is also possible.

By the way, in the transporting device having the structure in which the holding body 10 is moved back and forth by the four links as described above,
The distance between the ends of the pair of first links 5a and 5b attached to the turntable 1 and the first links 5
a pair of second links 8 connected to the other ends of a and 5b
If the distance between the ends of a and 8b does not match, one of the pair of first links 5a and 5b is rotated by the second motor 6 via the drive shaft 6a, and When the holding body 10 is driven back and forth by changing the angles of the first and second links, the tilt angle of the holding body 10 is deviated between the forward position and the backward position, that is, the holding body 10 is kept constant. Since it does not move back and forth in this posture, there is a deviation in its trajectory.

FIG. 8 shows a state in which the tilt angle is deviated between the forward and backward positions of the holder 10. That is,
In the forward position shown by the solid line and the retracted position shown by the chain line in the figure, the holding body 10 is inclined at an angle θ with respect to the straight line L of the forward and backward movement.

Such a deviation is caused by the first links 5a, 5
One end of b is rotatably attached to the turntable 1 via a bearing, or the other ends of the first links 5a and 5b are rotatably attached to one ends of the second links 8a and 8b. Since they are attached, the precision is caused when the above bearings are assembled into the first and second links, and the precision of each bearing varies.

If the tilt angle of the holding body 10 is deviated between the forward position and the backward position, the delivery accuracy of the semiconductor wafer held by the holding body 11 may be deteriorated, and in the worst case. In some cases, the delivery cannot be performed reliably.

Therefore, in order to improve the delivery accuracy of the semiconductor wafer, the first links 5a and 5b attached to the turntable 1 can be installed even if the accuracy of the bearing assembly or the accuracy of the bearing itself varies. It is desirable to be able to match the distance between the ends and the distance between the ends of the pair of second links 8a and 8b connected to the other ends of the first links 5a and 5b.

[0014]

As described above, in the related art, since the holding body is deviated in the inclination angle between the forward position and the backward position, it has been sometimes impossible to deliver the conveyed articles accurately. The present invention has been made based on the above circumstances, and an object of the present invention is to provide a space between one ends of a pair of first links and a pair of second links connected to the other ends of the first links. It is an object of the present invention to provide a carrier device capable of matching the distance between the ends.

[0015]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention provides a turntable which is rotatably driven by a first drive source in a carrying apparatus for carrying and positioning articles to be carried in the front-rear direction. An adjusting mechanism for adjusting a distance between the pair of first links, one end of which is rotatably supported by the turntable, and one end of the pair of first links, which is provided on the turntable. A pair of second links, one end of which is rotatably connected to the other end of the first link, and a holding unit which is rotatably connected to the other end of the second link and holds the transported article. And a second drive source that rotationally drives one of the first links and a second drive source that is provided at a connecting portion between the first link and the second link.
And a transmission mechanism for transmitting the rotation of the one first link driven by the drive source to the second link.

[0016]

According to the above construction, it is possible to adjust the distance between the ends of the pair of first links by the adjusting mechanism, and adjust the distance to match the distance between the ends of the second link.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 5 is an exploded perspective view of the transfer device, which has a column 21. This column 2
A turntable 22 is rotatably provided on the upper surface side of 1. One end of a pair of first links 23a and 23b is rotatably attached to the upper surface of the turntable 22. One end of one of the first links 23a has the above-mentioned target.
A first rotating shaft 24 protruding from the lower surface side of the table 22 is connected. The first rotary shaft 24 is rotatably driven by a link motor 25. At one end of the other first link 23b, as shown in FIG.
One end of the support shaft 51 is integrally provided, and the other end of the support shaft 51 is rotatably supported by a bearing 52 embedded in the turntable 22.

As shown in FIG. 1, one of the first links 2
An interval A between the rotation center of 3a and the rotation center of the other first link 23b can be set by an adjusting mechanism 53 provided in the turn table 22. The adjusting mechanism 53 is provided between the first rotary shaft 24 of the turntable 22 and the support shaft 51, that is, between one end of the one first link 23a and the other first link 23b. The first split groove 54a and the second split groove 54b provided along the radial direction are provided at the portion. Each split groove 54
a and 54b have a width of several mm.

One end of the first split groove 54a is open to one end in the radial direction of the outer peripheral surface of the turntable 22 and the other end is located between the first rotary shaft 24 and the support shaft 51. It is located on the other end side in the radial direction. The second split groove 54b is positioned such that one end thereof is opened to the other end in the radial direction of the turntable 22 and the other end thereof is separated from the other end of the first split groove 54a at a predetermined interval. ing.

As shown in FIG. 3, the turntable 2 described above is used.
2, a through hole 55 penetrating the first split groove 54a is formed at a portion corresponding to one end side of the first split groove 54a at a middle portion in the thickness direction. A draw screw 56 having 56a is rotatably inserted. A step portion 55a is formed at the open end of the through hole 55, that is, the outer peripheral surface of the turntable 2, and the head portion 56a of the draw screw 56 is engaged with the step portion 55a.

A first pin 57 is embedded in the tip portion of the through hole 55 along the thickness direction of the turntable 22, and the pulling screw 56 is screwed into the first pin 57. are doing. Therefore, if the pulling screw 56 is screwed in, the first portion 22a divided by the first split groove 54a of the turntable 22 and the second portion 22b are tightened, and the second portion 22b is tightened. Since 22b is displaced in the direction of narrowing the gap of the first split groove 54a, the distance A between the first rotating shaft 24 and the support shaft 51, that is, the pair of first links 23 is provided.
The distance between the ends of a and 23b can be reduced.

A screw hole 58 is formed at the side of the draw screw 56, the tip of which is opened to the first split groove 54a.
A push screw 59 is screwed into the screw hole 58. A second pin 60 is embedded in a portion 22a of the turntable 22 corresponding to the tip of the push screw 59.
Therefore, if the push screw 59 is screwed in while the pull screw 56 is loosened, the tip of the push screw 59 pushes the second pin 60, and the reaction force of the second pin 22b causes the second portion 22b to move. Since the first split groove 54a is displaced in the direction of expanding the gap, the gap A between the first rotary shaft 24 and the support shaft 51 can be increased.

Since the turntable 22 is provided with not only the first split groove 54a but also the second split groove 54b, the first portion 22b of the turntable 22 has the first portion 22b.
Although the displacement in the direction of coming into contact with and separating from the portion 23a is smoothly performed, the second portion 23b can be displaced without the second split groove 54b.

The first and second pins 57 and 60 are made of a material having higher rigidity (strength) than the turntable 22. Usually, the turntable 22 is made of aluminum in order to reduce the weight, and the rigidity is not sufficiently high. Therefore, if a pulling force or a pressing force is directly applied by the pull screw 56 or the push screw 59, it will be damaged early. Therefore, the first, which has higher rigidity than the turntable 22,
The force of the pull screw 56 or the push screw 59 is applied to the turntable 22 via the second pins 57 and 60.

A table model is provided on the lower surface of the column 21.
A table 26 is provided, and the table motor 26 is adapted to drive the turn table 22 to rotate via a second rotating shaft 27.

At the other ends of the pair of first links 23a, 23b, a pair of second links 28a, 28b are respectively provided.
Has one end rotatably connected via a connecting mechanism 29 described later. At the other ends of the second links 28a and 28b, as shown in FIG. 1, one end of the strip-shaped holder 31 and a middle portion thereof are interposed via a spacer 61 made of a material having a small frictional resistance, such as a synthetic resin. And are pivotally attached by a pair of mounting shafts 61. On the upper surface of the other end portion of the holding body 31, a holding portion 31a for engaging and holding the semiconductor wafer U as the transported article is formed.

As shown in FIG. 4, the connecting mechanism 29 has a first connecting shaft 33 rotatably supported by a pair of bearings 32 at the tip (the other end) of the one first link 23a. One end of the one second link 28a is connected to the upper end of the first connecting shaft 33.

A second connecting shaft 34 is rotatably supported by a pair of bearings 35 at the tip of the other first link 23b. One end of the other second link 28b is connected to the upper end of the second connecting shaft 34. As shown in FIG. 1, the interval between the first connecting shaft 33 and the second connecting shaft 34 is B.

A third connecting shaft 36 is mounted and fixed by a mounting body 37 on the lower surface side of one end of the other first link 23b. The lower end of the first connecting shaft 33 and the third connecting shaft 36 are inserted into the gear box 41,
Each is rotatably supported by a bearing 42.
The first main gear 43 is fitted to the first connecting shaft 33, and the second main gear 44 meshed with the first main gear 43 is fitted to the third connecting shaft 36. Has been done. The first main gear 43 and the second main gear 44 are connected to the first link 2
The rotational movement of 3a, 23b is caused by the second links 28a, 28b.
Constitutes a transmission mechanism for transmitting to.

As shown in FIG. 5, the pair of first links 23a and 23b, the turntable 22 and the gear box 41 constitute a first parallel link mechanism X. Further, the pair of second links 28a and 28b, the gear box 41 and the holding body 31 form a second parallel link mechanism Y.
Is composed.

The first main gear 43 has a gear portion 43 having a thickness about half that of the boss portion 43a and the second main gear 44.
b, an auxiliary gear 45 having the same gear shape as the first main gear 43 and meshing with the second main gear 44 is rotatably provided on the boss portion 43a.

A gap 46 is formed between the opposed side surfaces of the first main gear 43 and the auxiliary gear 45.
A spring 47 is provided in the. The spring 47 has one end connected to the side surface of the first main gear 43 and the other end connected to the side surface of the auxiliary gear 45 and is stretched. Thereby,
The auxiliary gear 45 is elastically biased in the rotation direction.

When the auxiliary gear 45 is biased in the rotational direction by the spring 47, the auxiliary gear 45 and the second gear
The main gear 44 is meshed with the main gear 44 in an elastically pressed state. That is, the meshing portion of the second main gear 44 is elastically sandwiched between the first main gear 43 and the auxiliary gear 45. Thereby, the backlash in the meshed state between the first main gear 43 and the second main gear 44 is removed.

According to the transport device having such a structure,
The first rotary shaft 24 and the support shaft 5 provided on the table 22.
A pair of first links 23a, 23b, which is the distance from
The distance A between the ends of the table can be adjusted by the adjusting mechanism 53 provided in the turntable 22. That is,
If the pulling screw 55 is screwed in while the push screw 59 is loosened, the gap A of the first split groove 54a can be narrowed and the interval A can be made small. If the screw 59 is screwed in, the first split groove 54a can be expanded and the distance A can be increased.

Therefore, the pair of first links 23a,
The distance A between the ends of 23b is equal to the distance between the pair of second links 28.
It can be adjusted to match the distance B between the ends of a and 28b. That is, when the intervals A and B do not precisely match due to insufficient assembly accuracy or variations in the accuracy of the bearings 32, 35, 52 of the respective parts, the adjusting mechanism 53 described above. The distance A can be adjusted to match the distance B by.

If the distances A and B can be made to coincide with each other in this way, the link motor 25 is actuated and the holding member 3 is operated.
Even if 1 is moved back and forth, this holder 31 moves back and forth in a fixed posture, and there is no deviation in the tilt angle between the forward position and the backward position, so that the semiconductor wafer U can be delivered precisely. It will be possible.

If the link motor 25 is stopped at the forward or backward position of the holder 31, the holder 3
The linear motion of 1 is stopped and the holder 31 can be positioned. At that time, the coupling mechanism 29 for transmitting the rotational movement of the first parallel link mechanism X to the second parallel link mechanism Y.
If there is backlash between the pair of main gears 43 and 44 due to backlash, the positioning accuracy will be reduced.

However, the pair of main gears 43, 4
Since the backlash between the four is removed by the auxiliary gear 45, the positioning accuracy of the holding body 31 does not deteriorate when the linear movement is stopped.

Moreover, the auxiliary gear 45 is elastically biased by the spring 47 and meshes with the second main gear 44. Therefore, when the linear motion is stopped, the pair of main gears 43,
Even if vibration occurs due to the backlash between the gears 44, the vibration is canceled by the elastic force, that is, the frictional force, which the auxiliary gear 45 applies to the second main gear 44, so that the vibration is quickly damped.

That is, according to the above configuration, the adjusting mechanism 5
3 makes it possible to move the holder 31 back and forth in a fixed posture, and at the time of a predetermined forward position and backward position, there is no positional deviation due to backlash between the pair of main gears 43, 44. Together with this, the delivery accuracy of the semiconductor wafer U can be significantly improved.

While positioning the holder 31 in the front-rear direction, the table motor 26 is operated to turn the turntable.
When the bull 22 is rotated, the first and second parallel link mechanisms X and Y are interlocked with the rotation, so that the holder 31 can be positioned in the rotational direction.

[0042]

As described above, according to the present invention, one end of the pair of first links, one end of which is attached to the turntable,
The distance between the ends can be adjusted by an adjusting mechanism.

Therefore, the distance between the ends of the first link can be adjusted to match the distance between the ends of the second link connected to the other end of the first link.
The holder for holding the conveyed article, which is connected to the other end of the link, can be moved forward and backward in a fixed posture. Thereby, it may be possible to deliver the conveyed article with high accuracy.

Further, since the adjusting mechanism is composed of the split groove formed in the ten table, the pull screw for narrowing the interval of the split groove, and the push screw for expanding the split groove, not only the construction is simple, but also the adjustment is possible. Work can be done easily.

[Brief description of drawings]

FIG. 1 is a plan view of a link mechanism showing an embodiment of the present invention.

FIG. 2 is a side view of the same.

FIG. 3 is an enlarged view of the adjusting mechanism.

[FIG. 4] Similarly, the rotational movement of the first parallel link mechanism is changed to the second movement.
FIG. 5 is a cross-sectional view of a connecting mechanism that transmits the parallel link mechanism of FIG.

FIG. 5 is an exploded perspective view of the entire device.

FIG. 6 is a partial plan view of the first main gear and the auxiliary gear.

FIG. 7 is an explanatory view of a conventional transfer device.

FIG. 8 is an explanatory diagram of a tilted state of the holding body at the forward movement position and the backward movement position.

[Explanation of symbols]

22 ... Turntable, 23a, 23b ... First link, 25 ... Link motor, 26 ... Table motor, 28
a, 28b ... second link, 31 ... holding body, 31a ... holding part, 43, 44 ... main gear, 47 ... spring, 53 ... adjusting mechanism, 54a, 54b ... split groove, 56 ... draw screw, 59 ...
Push screw.

Claims (2)

[Claims] 1. A transport device for transporting and positioning an article to be transported in the front-rear direction, and a turntable which is rotationally driven by a first drive source, and one end of which is rotatably supported by the turntable. A pair of first links, an adjusting mechanism provided on the turntable for adjusting a distance between one ends of the pair of first links, and one end of the other ends of the first links being rotatable. A pair of second links connected to each other, a holder having a holding portion rotatably connected to the other end of the second link to hold the transported article, and one of the first links to rotate. The second drive source for driving and the rotation of one of the first links provided at the connecting portion of the first link and the second link and driven by the second drive source are rotated by the second link. And a transmission mechanism for transmitting to Apparatus. 2. The adjusting mechanism is a split groove formed in a radial direction at a portion between one end of one first link of the turntable and one end of the other first link. And a push screw for narrowing the gap between the split grooves and a push screw for widening the gap between the split grooves.
The transport device described.