JP2000232148A - Positioning device for tabular work - Google Patents

Abstract

PROBLEM TO BE SOLVED: To position a tabular work in a non-contacting state without raising dust. SOLUTION: A positioning device has a plate 1 for floating provided with an upper plate 11 having air holes 11a, a lower plate 12, both side plates 13, an air chamber 14, etc.; a pin-up mechanism 2 provided with air cylinders 21, rods 22, supporting plates 23, work supporting pins 24, etc.; and a positioning device 3 provided with a linear guide section 32, support sections 33, arms 35 which are rotatably supported by pins 34, positioning pawls 36 having air blowing-out ports 36a, an air pipe system 37, etc. The positioning device positions a pin-upped work W in such a way that the device lowers the work W onto the plate 1, floats the work W to a height δh1 from the plate 1, and supports the work W in the floating state. In addition, the device positions the work W by again floating the work W by an amount δh2 which is smaller than the amount δh1 by blowing down air from the positioning pawls 36. Therefore, the positioning device can position the work W in a non-contacting state without raising dust.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning device for positioning a flat work, and is particularly advantageously used in a field requiring a high-level clean environment such as a process for manufacturing an LCD glass substrate or a silicon wafer. .

[0002]

2. Description of the Related Art For example, in a conventional alignment apparatus in a process of manufacturing a glass substrate for an LCD, a substrate is lifted and supported by a support pin, and in this state, positioning is performed by pressing a claw in the XY directions. When the substrate size was small, there was no problem with this positioning method, but with the recent enlargement of the substrate, the friction between the substrate and the pins increased, and the dust generated due to the sliding friction between the substrate and the support pins increased. It has become difficult to position a substrate in a clean state.

In addition, a substrate having a diameter of 8 inches is supported by three support pins, and air is blown out from the support pins to discharge air from between the tops of the support pins and the rear surface of the substrate, so that the floating and suction of the substrate is performed. There has been proposed a substrate transfer device in which the substrate is generated and the substrate is positioned by a guide member in this state (see JP-A-8-330383). However, in this device, the floating air is blown out from a small number of support pins, so that the substrate supporting force due to dynamic pressure is small, and the substrate supporting force due to static pressure does not occur, so that it is not easy to float the substrate. In particular, floating support becomes difficult for a large substrate.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in the prior art, and to provide a flat work positioning apparatus which can reliably float and support even a large flat work. As an issue.

[0005]

In order to solve the above-mentioned problems, the present invention provides a positioning device for positioning a flat work, comprising: a face plate having a number of holes through which air is blown; A plurality of support pins formed so as to be switchable between a position and a retracted position and capable of supporting the flat work when protruding, and a first position for positioning the flat work in proximity to an end surface of the flat work. A positioning member movably formed between a second position distant from the front plate and an air outlet facing the face plate to blow air in the direction of the face plate; And a plurality of positioning members formed so as to be possible.

[0006]

1 and 2 show a schematic overall configuration of a positioning apparatus to which the present invention is applied and a partially enlarged view thereof.

The present apparatus is an apparatus for positioning a work W composed of a glass substrate for LCD which is a flat work.
The main components include a floating plate 1, a pin-up mechanism 2, and a positioning mechanism 3.

The levitation plate 1 has a thin sheet metal structure, and comprises an outer plate composed of thin upper and lower plates 11, 12 and both side plates 13, and a rib plate (not shown) for reinforcing these inside. . The internal air chamber 14 is supplied with air by a blower (not shown), for
It has a pressure of about 0 mmAq. In this example, the upper plate 11 corresponds to a face plate having many holes 11a from which air is blown out. FIG. 1 shows only a part of the large number of holes 11a. It should be noted that the floating plate 1 may be a solid plate having a thickness and strength instead of having such a thin sheet metal structure.

The pin-up mechanism 2 includes an air cylinder 21,
It is composed of the rod 22, a support plate 23 connected thereto, and a work support pin 24 supported by the support plate 23. Workpiece support pins 24, by the operation of the air cylinder 21, can be switched between a lower position H ₂ retracted as dashed line position H ₁ and two points on a solid protruding from upper plate 11 of the floating plate 1 It has become. Work support pin 24
Are provided. When the workpiece W projects, the work W
Can be supported at the top.

The positioning mechanism 3 comprises a gantry 31, a linear guide portion 32, a column portion 33, an arm 35 rotatably supported on the column portion via a pin 34, a positioning claw 36, an air pipe system 37, and the like. I have. The positioning claw 36
In this example, as shown in FIG. 2B, eight workpieces W are provided around the workpiece W so that the workpiece W can be positioned. The movable part of the positioning mechanism 3 is driven in the X or Y direction by a linear reciprocating mechanism (not shown) such as a ball screw mechanism, depending on the mounting position of the claw. As a result, each positioning claw 36 becomes X
It can move in the direction or the Y direction.

With such a configuration, the positioning claw 36
The movement between the outer positions L ₂ of the second position shown in the coming apart solid inner position L ₁ of the first position indicated by the two-dot chain line to position it in proximity to the end face Ws of the workpiece W It is possible. Further, an air outlet 36a facing the upper plate 11 and blowing air in the direction is provided. A low-pressure compressed air of, for example, about 1 kgf / cm ² G is supplied from the air pipe system 37 to the air outlet 36a.
Further, the pivoting arm 35 is supported by the pin 34 to be rotatable, so that the positioning claw 36 is formed so as to move in the vertical Z direction and to be able to contact and separate from the upper plate 11.
According to the positioning device as described above, the alignment of the work W to the target position is performed as follows.

[0012] 1) work supporting pin 24 is in the position H ₁ on which projects, the work W is placed on this. In this case, positioning pawl 36 stands by at the outside position L ₂ retracted away from the workpiece W.

2) Hole 11 in upper plate 11 of floating plate 1
air from the air cylinder 2
1 and the lower position H where the work support pin 24 is retracted.
_Then , the work W is lifted and supported on the upper plate 11.

3) Air is supplied from the air pipe system 37 to the positioning claw 36, and the air is blown out from the air outlet 36a, so that the positioning claw 36 floats. Next, the support 33
Move the X or Y direction along the positioning pawl 36 to the linear guide portion 31 with equal, it is moved to the inner position L ₁ for positioning the workpiece W, the alignment of the workpiece W. 4) The supply of the air for lifting the work is stopped, and the work W is placed on the upper plate 11 in a state where the lift is reduced and the alignment is performed.

5) With the positioning claw 36 floating, L ₁
Position from the retracted to the L ₂ position, then the supply of the floating air stops, stabilizes Lower the upper surface 11.

[0016] 6) by operating the air cylinder 21 again raises the workpiece support pins 24, lifting it by supporting the workpiece W by the alignment state to the upper position H _1,
Terminate the positioning. In this state, the workpiece W positioned with high accuracy is picked up by a robot hand or the like, and is accurately transferred to the mounting location in the next step.

In the work alignment described above, when the work is floated and positioned, it is desirable to stabilize the floating state. For this purpose, the work W is supported at a certain number of points in a uniform distribution, and the flow rate of the blown air, and hence the pressure P in the air chamber 14, is increased.
₁ without too large, it is desirable not to increase too much the flying height .delta.h _1. In the present invention, since the air is blown out from the large number of holes 11a, the work W can be uniformly and stably supported.
Further, since an air layer A having a pressure is formed between the work W and the upper plate 11, a supporting force due to static pressure is generated in the work W, and a large work is supported even at a pressure of about a low pressure blower. Sufficient supporting force is generated. According to experiments by the inventors, when the pressure P1 is set to about ₁₀ to 20 mmAq,
The result that the floating amount of the work W made of a glass substrate larger than 500 mm square was about 0.5 mm to 1 mm was obtained.

When the positioning claw 36 moves between the inner and outer positions L ₁ and L ₂ , it floats from the upper plate 11 and moves without contact therewith. As a result, dust generation due to claw movement is prevented. In addition, a clearance is provided between the positioning claw 36 and the end surface Ws of the workpiece W within an allowable error in alignment. However, the outer surface of the positioning claw 36 may be made to be an elastic body so as to lightly contact the end surface of the work. Also in this case, since there is almost no sliding between the claws and the work, no dust is generated.

The floating amount δh ₂ of the positioning claw 36 needs to be set to a small value of about 0.1 to 0.3 mm in relation to the floating amount of the work W. In this case, when supplying the pressure P ₂ air to the air outlet 36a of the positioning pawl 36, the diameter of the positioning pawl 36 if d, as the largest force to the pawl F = πd _² P ^2/4 is upwardly Works. For example the pressure P ^₂ 1kgf / cm ₂ G, if the area of the air outlet 36a and 1 cm ^2, F is the 1kgf / cm ² f. This force is excessive when considering the weight of the arm 35 and the positioning claw 36. However, when the positioning claw 36 floats and air is blown out between the positioning plate 36 and the upper plate 11, F immediately becomes a small value,
The relationship between F and δh ₂ is determined, and an appropriate flying height δh ₂ is secured.

As a result, according to such a floating system,
It is easy to maintain δh ₂ at a slight value as described above. If the positioning claw 36 slightly floats from the upper plate 11, the contact between them can be reliably prevented. As shown in the figure, a tension or compression spring 38 may be attached to adjust the floating force of the positioning claw 36. Further, if necessary, a counterweight may be provided on the opposite side of the claw 36 with respect to the pin 34 so that the positioning claw 36 floats with a lower pressure.

By the way, if it is attempted to mechanically provide a small gap of about δh ₂ without causing the positioning claw 36 to float, since the claw moving mechanism is interposed, δh ₂
It is difficult to obtain the mechanical accuracy enough to maintain. or,
It is difficult to secure δh ₂ from the viewpoint of the surface accuracy of the floating plate 1. As a result, even though the workpiece W is in a floating state in which no dust is generated at the time of positioning, the positioning claw 36 slides on the floating plate 1 to generate dust, and as a result, a clean work processing environment cannot be obtained. Will be.

In this embodiment, a mechanism for rotating the arm 35 is used so that the positioning claw 36 can float. However, the arm 35 can be moved up and down with a slide bearing or the like interposed therebetween. May be a mechanism that allows the surface to float. In addition, the levitation plate 1, the pin-up mechanism 2, and the positioning mechanism 3 are arranged in multiple stages, the levitation air is heated to high-temperature air, and the levitation plate 1 is disposed in a high-temperature environment.
It is also possible to use the positioning device as a hot air circulation type heat treatment device.

[0023]

According to the present invention, since a face plate having a large number of holes through which air is blown out is provided, a flat work (hereinafter simply referred to as "work") can be floated and supported thereon.
Since a plurality of support pins are provided so as to be switchable between a position protruding from the face plate and a retracted position and capable of supporting the work at the time of protrusion, the support pins that support the work and are in the protruding state from the face plate are provided. By retracting, the workpiece can be supported in a non-contact floating manner on the face plate. Since the positioning member is formed so as to be movable between a first position which is positioned close to the end face of the work and a second position which is distant therefrom, the work is levitated and supported on the face plate as described above. The positioning member is kept waiting at the second position until the workpiece is floated and supported, and can be moved to the first position to position the workpiece. At this time, since the work is floating, the work does not come into contact with the support pins and the face plate, and clean positioning without dust generation can be performed.

The positioning member has an air outlet facing the face plate and blows air in the direction, and is formed so as to be able to come in contact with and separate from the face plate, so that the air is blown out from the air outlet. Thus, the positioning member can be lifted from the face plate and separated therefrom. As a result, by causing the positioning member to float before moving from the second position to the first position, the positioning member is moved from the second position to the first position in a non-contact state with the face plate, and returns to the original position after positioning. It is possible to recover and prevent dust generation due to contact sliding during movement.

After positioning the work in a state where no dust is generated in this way, by setting the support pins to the projecting position, the positioned work is separated from the face plate and supported on the support pins. It is possible to make it possible to transfer to. At this time, since the work no longer needs to be moved for positioning, the support pin only lifts the work and does not slide on the work. As a result, the workpiece can be positioned completely without dust generation.

[Brief description of the drawings]

FIG. 1 is a front view showing an example of a schematic overall configuration of a work positioning device to which the present invention is applied.

FIG. 2A is a front view including a partial cross section showing a state in which a part of the device is enlarged, and FIG. 2B is a plan view showing an example of arrangement of positioning claws with respect to a work.

[Explanation of symbols]

11 upper plate (face plate) 11a hole 24 work support pins (support pins) 36 positioning pawl (positioning member) 36a air outlet H ₁ upper position (projecting position) H ₂ lower position (retracted position) L ₁ inside position ( first position) L ₂ outer position (second position) W workpiece (plate-shaped work) Ws end face

Claims (1)

[Claims] 1. A positioning device for positioning a flat work, comprising: a face plate having a large number of holes through which air is blown; and a switchable position between a position protruding from the face plate and a retracted position. A plurality of support pins capable of supporting the flat work, and formed to be movable between a first position for positioning the flat work close to an end face of the flat work and a second position away from the first position. A plurality of positioning members which are provided with an air outlet which is opposed to the face plate and in which air is blown out in the direction of the face plate, and which is formed so as to be able to approach and separate from the face plate. Characteristic positioning device.