JP2000062951A - Conveying apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain stable conveyance of an object to be conveyed in a floating condition and prevent generation of dust and degradation of cleanness in a clean room. SOLUTION: Conveyers 41, 42 are provided with permeable ceramic materials 12, air supply pipes 13 jetting air through the permeable ceramic materials, retaining mechanisms retaining a glass substrate 11 floated by jetting air at a fixed position, drive parts 32 and belts 33. A conveying apparatus is provided with a rotation drive part 22 which moves the air supply pipes 13 while rotating in addition to the permeable ceramic materials 12 and the air supply pipes 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for transporting a liquid crystal glass substrate, a silicon wafer or the like in a floating state.

[0002]

2. Description of the Related Art Conventionally, when a liquid crystal glass substrate or the like is conveyed, a liquid crystal glass substrate is stored in a dedicated cassette and the cassette is conveyed by a belt conveyor, or a robot arm is provided with a vacuum suction pad. For example, a method is used in which an arm is operated while a glass substrate is adsorbed to carry the glass substrate.

On the other hand, there is a technique in which an object is levitated and transported by ejecting a gas from the surface of a ceramics porous body or the like, as disclosed in Japanese Patent Laid-Open Nos. 63-273781 and 6-63.
It is disclosed in Japanese Patent Application Laid-Open No. 3-290388, Japanese Patent Application Laid-Open No. 1-167582, and the like.

[0004]

Currently, the size of the liquid crystal glass substrate is mainly 760 mm × 800 mm × 1.1 mm, but in the case of the liquid crystal glass substrate for personal computer, the image becomes clearer as the plate thickness becomes thinner. Because of the tendency, recently, 800 mm x 1100 mm x 0.7
The demand for mm size is increasing.

However, when the plate thickness becomes 0.7 mm, a bending of about 40 mm occurs near the center of the liquid crystal glass substrate due to its own weight. Therefore, in the conventional method of storing in a cassette and carrying it by a belt conveyor, The liquid crystal glass substrate is often dropped and damaged by vibration, or the liquid crystal glass substrate is often damaged due to bending due to its own weight.

On the other hand, when the liquid crystal glass substrate is transferred by using a robot arm or the like, the liquid crystal glass substrate is sucked by the vacuum pad of the arm, but the liquid crystal glass substrate may be damaged when the vacuum is released. Many.

In order to solve such a problem, a method of levitating the liquid crystal glass substrate without bending it and adsorbing it with a vacuum pad or the like, that is, a jet of air is collided with the lower surface of the liquid crystal glass substrate. The liquid crystal glass substrate may be levitated by the momentum of the air jet.

However, when the floating method using an air jet is adopted, as shown in FIG. 6, the constant air flow (one-way flow 35) generated in the clean room 34 for maintaining cleanliness is An operator 36 is disturbed by the jet
Since the dust generated from the air deteriorates the cleanliness in the clean room 34, such a floating method using an air jet cannot be adopted.

On the other hand, Japanese Patent Laid-Open No. 63-273781,
JP-A-63-290388, JP-A 1-1675
The levitation transportation technology disclosed in Japanese Unexamined Patent Publication No. 82, etc. is for levitation and transportation of an object by ejecting gas from the surface of a ceramic porous body or the like, and a powerful gas jet constantly disturbs the area around the object. Since a flow is generated, it cannot be adopted as a means for transporting a liquid crystal glass substrate or the like in a clean room for the same reason as described above.

[0010] Therefore, the problem to be solved by the present invention is that the object to be conveyed can be stably conveyed in a floating state without generating dust or deteriorating the cleanliness of the clean room. It is to provide a carrier.

[0011]

In order to solve the above-mentioned problems, a carrying apparatus of the present invention is provided with a plurality of air-permeable ceramic materials dispersedly arranged according to the shape of an object to be transferred, and an upper room through the air-permeable ceramic material. A gas supply means for ejecting a gas, and a holding mechanism for holding a conveyed object floating by the gas ejected from the gas permeable ceramic material at a fixed position,
A moving mechanism for moving the gas supply means and the holding mechanism. Here, the distributed arrangement according to the shape of the conveyed object means the dispersed arrangement within the range of the horizontal projection of the conveyed object.

With this structure, the gas ejected from the plurality of gas permeable ceramic materials forms a gas film on the upper surface of each gas permeable ceramic material.
The transported object can be stably floated by these gas films, and the transported object can be transported in the floating state by operating the moving mechanism in this state. In this case, since the transported object is held at a fixed position by the holding mechanism, the transported object does not separate from or fall directly above the breathable ceramic material during the operation of the moving mechanism.

Further, the ejected gas for levitating the transported object is
Since the gas is ejected in a finely dispersed state by passing through the voids inside the air-permeable ceramic material, the unidirectional flow in the clean room is not disturbed and the cleanliness is not deteriorated. Further, in a clean room level environment, since the breathable ceramic material itself does not oxidize or deteriorate, no dust is generated even if it is used for a long period of time.

On the other hand, in the carrying apparatus of the present invention, the gas supply means is provided with the gas supply pipes arranged substantially in parallel, and the gas outlets formed in the gas supply pipes to which the breathable ceramic material can be attached. , For a plurality of breathable ceramic materials distributed and arranged according to the shape of the transported object,
Since it is possible to supply the gas uniformly and stably, the transported object can be stably floated.

Further, in the carrying apparatus of the present invention, as a holding mechanism, a plurality of air-permeable ceramic materials dispersed around the object to be transferred, and gas is ejected toward the object to be transferred through these air-permeable ceramic materials. By providing the gas supply means for carrying, it becomes possible to hold the transported object at a fixed position by the jetted gas, so that it is possible to transport the transported object in a so-called non-contact state, and to prevent damage or damage of the transported object. It is effective in prevention.

Further, in the carrying apparatus of the present invention, the moving mechanism is provided with a means capable of moving the gas supply means and the holding mechanism in parallel and rotationally, so that the object to be carried can be carried in any direction. Since it becomes possible, convenience at the time of forming a series of conveyance lines improves.

In the carrying apparatus of the present invention, the porosity of the air-permeable ceramic material is set to 30% to 50% so that the carried object can be stably levitated with the minimum required gas ejection amount. It is possible to prevent the unidirectional flow in the clean room from being disturbed. If the porosity of the breathable ceramic material is less than 30%, the pressure loss of the gas tends to be large and the levitation ability tends to decrease, and if it exceeds 50%, the ejection amount increases and the unidirectional flow in the clean room is Since the possibility of disturbance increases, it is desirable to set it within the range of 30% to 50%.

Further, in the carrying apparatus of the present invention, by using a porous sintered body containing alumina and any one or more of silica, titania, magnesia, calcia and yttria as the breathable ceramic material, Since the oxidation resistance and the like are further improved and the secular change is eliminated, dust and the like are not generated, and stable gas ejection can be performed for a long period of time.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a state in which the carrier devices according to the embodiments are combined, and FIGS. 2 and 3 are perspective views of the respective carrier devices.

In the present embodiment, as shown in FIG. 1, two transfer devices 41 and 42 capable of linearly moving the glass substrate 11 as the object to be transferred, and the glass substrate 1 are provided.
1 is combined with a transfer device 40 capable of rotating and moving 1 to form a series of transfer lines. The two transfer devices 41 and 42 each have a structure as shown in FIG. 2, and the transfer device 40 has a structure as shown in FIG. Note that the holding mechanism is omitted in FIG.

As shown in FIG. 2, the transporting devices 41 and 42 are provided with a plurality of breathable ceramic materials 12 dispersedly arranged in accordance with the shape of the glass substrate 11 to be transported, and through the breathable ceramic material 12 upward. (F) A plurality of air supply pipes 13 arranged in parallel for ejecting air, a holding mechanism for holding the glass substrate 11 floated by the air ejected from the air-permeable ceramic material 13 at a fixed position, the air supply pipe 13, and the holding mechanism. The drive unit 32 and the belt 33 for moving the mechanism along the rail 20 are provided. Here, the plurality of breathable ceramic materials 12 are the glass substrate 1
1 is distributed and arranged within the range of the horizontal projection.

On the other hand, as shown in FIG. 3, the carrying device 40 is provided with a plurality of air-permeable ceramic materials 12 dispersedly arranged in accordance with the shape of the glass substrate 11 which is the object to be transferred, and through the air-permeable ceramic material 12 upward. (F) A plurality of air supply pipes 13 arranged in parallel for ejecting air, a stopper 21 for holding the glass substrate 11 floated by the air ejected from the air-permeable ceramic material 13 at a fixed position, an air supply pipe 13 and the like are rotated. It is provided with a rotation driving unit 22 and the like for moving. Here, a plurality of breathable ceramic materials 1
2 are distributed and arranged within the range of the horizontal projection of the glass substrate 11.

Here, the plurality of air supply pipes 13 are connected to the holder 2
It is fixed to the rotary plate 24 in a state of being integrated by 3,
Since the rotary plate 24 is fixed to the rotary shaft 25 of the rotary drive unit 22, the plurality of air supply pipes 13 can rotate around the rotary shaft 25, and the floated glass substrate 11 can be rotationally moved. . Further, since the rotating shaft 25 can be moved up and down in the axial direction by the air cylinder 26, the floated glass substrate 11 can be moved in the vertical direction.

Further, the air supply pipe 1 of the transfer devices 41 and 42
3 and the air supply pipe 13 of the transfer device 40 are arranged at intervals such that they do not cross each other and come into contact with each other. Therefore, as shown in FIG. 1, the glass substrate 11 is interposed between the transfer devices 41 and 42 and the transfer device 40. Can be handed over.

With this structure, the glass substrate 11 linearly transported by the transport device 41 is moved to the transport device 40, and the glass substrate 11 is rotated 90 degrees by the transport device 40, and then the transport device 40 is transported. The glass substrate 11 can be transferred to 42, and thereafter the glass substrate 11 can be linearly transported by the transport device 42. In these carrying processes, as will be described later, the glass substrate 11 can be carried in a completely non-contact state, so that the glass substrate 11 can be prevented from being damaged.

The transfer line shown in FIG. 1 is a combination of linear movement and 90-degree rotational movement, but the present invention is not limited to this. It is possible to construct an arbitrary transfer line such as a transfer line including rotational movement or a transfer line involving vertical movement, and all of these transfer lines can be made non-contact.

Here, with reference to FIGS.
The levitation mechanism in Nos. 1 and 42 will be described. 4 is a perspective view showing the transport mechanism, and FIG. 5 is a sectional view taken along the line AA of FIG.

In the levitation mechanism 10 of the transfer devices 41 and 42, a plurality of air supply pipes 13 are arranged in parallel on the base material 15, and a plurality of breathable ceramics are formed in accordance with the shape of the glass substrate 11 which is a floating object. The material 12 is distributed and arranged in these air supply pipes 13. Also, the air supply pipe 1
Compressed air is supplied to 3 via an air hose 14, and this compressed air is jetted upward through the air-permeable ceramic material 12. Further, the base material 15 is the rail 20.
It is locked to slide freely. The breathable ceramic material 12 is attached to each of the air outlets 13 a formed in the air supply pipe 13.

The air ejected from the plurality of air-permeable ceramic materials 12 forms an air film on the upper surface of each air-permeable ceramic material 12, so that these air films cause
The glass substrate 11 can be floated at a position of about 1 mm from the breathable ceramic material 12. In this case, since the glass substrate 11 is floated by the air ejected from the plurality of dispersed air-permeable ceramic materials 12, the glass substrate 11 is not bent due to its own weight and is not likely to be damaged.

In the levitation mechanism 10, the glass substrate 11
As a holding mechanism of the stopper 2 around the glass substrate 11
1a and 21b are distributed, but the stopper 21
a and 21b are respectively made of breathable ceramic material 21x,
21y is attached, and air is ejected toward the glass substrate 11 toward the glass substrate 11 through these breathable ceramic materials 21x and 21y.

Therefore, it is possible to hold the glass substrate 11 floating by the air blown from the breathable ceramic material 12 at a fixed position by the air jetted from the breathable ceramic materials 21x and 21y. The glass substrate 11 can be held in a fixed position by contact. As a result, it is possible to prevent the glass substrate 11 from arbitrarily moving during floating, and therefore, it is possible to prevent damage and the like due to the glass substrate 11 dropping during transportation. Note that the levitation mechanism of the transfer device 40 has substantially the same structure and function as the levitation mechanism 10 described above, and therefore a description thereof will be omitted.

Next, with reference to FIG. 6, a usage state of the transfer device in the clean room will be described. FIG. 6 is a front view showing a usage state of the transport device. In FIG. 6, the stoppers 21a and 21b of the levitation mechanism are omitted.

As described above, the air jetted from the breathable ceramic materials 12, 21x, 21y constituting the levitation mechanism 10 is the breathable ceramic materials 12, 21x, 21y.
As it is ejected in a finely dispersed state by passing through the internal voids, as shown in FIG. 6, it does not disturb the unidirectional flow 35 formed in the clean room 34, and is generated by the worker 36. The generated dust does not adhere to the glass substrate 11 and the cleanliness of the clean room 34 does not deteriorate.

In addition, even if the gas-permeable ceramic material 12, 21x, 21y itself is not oxidized or deteriorated even if it is operated for a long period of time in the clean room 34, it becomes a source of dust. Nor.

On the other hand, in the levitation mechanism 10, when the porosity of the breathable ceramic materials 12, 21x, 21y is set to 35%, the glass substrate 11 has the minimum necessary air ejection amount.
Can be stably levitated, and clean room 3
It was possible to carry out a smooth transfer work without disturbing the one-way flow 35 in 4.

Further, in the levitation mechanism 10, a porous sintered body containing alumina and silica is used as the breathable ceramic materials 12, 21x, 21y. The porous sintered body is
A mixture of ceramic particles having a particle diameter of 10 μm to 100 μm and an additive is sintered by pressurizing and heating, and a large number of fine voids are formed in the mixture, and a total of 35 The porosity is about%. Further, in addition to alumina and silica, it is also possible to use a porous sintered body containing titania, magnesia, calcia, yttria, or the like.

The breathable ceramic materials 12, 21
The porosities of x and 21y can be adjusted by changing the particle size of the ceramic particles as the raw material, the type of additive material, the pressure applied, the sintering temperature, etc., so the porosity suitable for the working conditions is set. can do. Since this porous sintered body is unlikely to be oxidized or deteriorated in the air, it does not generate dust or the like and can stably eject air for a long period of time.

Next, another embodiment of the levitation mechanism will be described with reference to FIGS. 7 is a plan view showing a levitation mechanism according to another embodiment, FIG. 8 is a side view of the levitation mechanism, and FIG. 9 is a front view of the levitation mechanism.

The levitation mechanism 50 of the present embodiment is for levitation of a disk-shaped silicon wafer 51, and a plurality of air supply pipes 52 arranged in parallel are arranged in parallel with each other in accordance with the shape of the silicon wafer 51. Breathable ceramic materials 53 are dispersed. Also, silicon wafer 5
A stopper 54 provided with a breathable ceramic 54a is arranged on the outer periphery of 1. The air that has passed through the breathable ceramic material 53 is jetted upward,
The air that has passed through a is jetted toward the silicon wafer 51.

With such a structure, the silicon wafer 51 can be stably levitated as in the case of the levitating mechanism 10, and the levitated silicon wafer 51 is blown by the air blown through the air permeable ceramic 54a. Holds in place. Therefore, by replacing the floating mechanism 10 of the transfer devices 40, 41, 42 described above with the floating mechanism 50, it is possible to provide a transfer device that can transfer the silicon wafer 51 without contact.

Also in the case of the levitation mechanism 50, since the air jetted through the breathable ceramic materials 53 and 54a does not disturb the surrounding air flow, a part of the transfer device in the clean room 34 as shown in FIG. However, it does not deteriorate the cleanliness or become a dust source. Therefore, the levitation mechanism 50 operates in the clean room 34.
It can be used for a long period of time.

[0042]

According to the present invention, the following effects can be obtained.

(1) A plurality of gas permeable ceramic materials dispersed and arranged according to the shape of the transported object, gas supply means for discharging gas upward through the gas permeable ceramic material, and gas discharged from the gas permeable ceramic material. By the holding mechanism for holding the transported object floating by the fixed position at a fixed position and the moving mechanism for moving the gas supply means and the holding mechanism, the transported material is carried by the gas film formed on the upper surface of each breathable ceramic material. It is possible to stably convey an object while it is levitated. Further, since the transported object is held at a fixed position by the holding mechanism, the transported object does not come off or fall directly above the breathable ceramic material.

(2) The jetted gas that floats the transported object is
Since the gas is ejected in a finely dispersed state by passing through the voids inside the air-permeable ceramic material, the unidirectional flow in the clean room is not disturbed and the cleanliness is not deteriorated. Further, in a clean room level environment, since the breathable ceramic material itself does not oxidize or deteriorate, no dust is generated even if it is used for a long period of time.

(3) The shape of the object to be conveyed is provided by providing a gas supply pipe arranged substantially in parallel as the gas supply means and a gas outlet formed in the gas supply pipe and into which a gas permeable ceramic material can be mounted. Since it becomes possible to uniformly and stably supply the gas to the plurality of air-permeable ceramic materials that are dispersed and arranged in accordance with the above, the transported object can be stably floated.

(4) As a holding mechanism, a plurality of gas permeable ceramic materials dispersed around the object to be conveyed and gas supply means for ejecting gas toward the object to be conveyed through these gas permeable ceramic materials. The provision makes it possible to hold the transported object at a fixed position with the jetted gas, so that it can be transported in a so-called non-contact state, which is effective in preventing damage and damage to the transported object.

(5) By providing the moving mechanism that can move the gas supplying means and the holding mechanism in parallel and rotationally, it becomes possible to convey the object to be conveyed in an arbitrary direction. The convenience when forming the transport line is improved.

(6) The porosity of the breathable ceramic material is 3
By setting it to 0% to 50%, it becomes possible to stably levitate the transported object with the minimum required gas ejection amount,
It does not disturb the one-way flow in the clean room.

(7) Oxidation resistance can be further improved by using a porous sintered body containing alumina and one or more of silica, titania, magnesia, calcia, and yttria as the air-permeable ceramic material. As a result, the stable gas ejection can be performed for a long period of time without generating dust or the like.

[Brief description of drawings]

FIG. 1 is a perspective view showing a state in which a plurality of transfer devices according to an embodiment are combined to form a transfer line.

FIG. 2 is a perspective view of the transfer device shown in FIG.

FIG. 3 is a perspective view of the transport device shown in FIG.

FIG. 4 is a perspective view showing a levitation mechanism of the transport device of FIG.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a perspective view showing a usage state of the transport device.

FIG. 7 is a plan view showing another embodiment of the levitation mechanism.

8 is a side view of the levitation mechanism shown in FIG.

9 is a front view of the levitation mechanism shown in FIG.

[Explanation of symbols]

10, 50 Floating mechanism 11 Glass substrate 12, 21x, 21y, 53, 54a Breathable ceramic material 13, 52 Air supply pipe 13a Air outlet 15 Base material 14 Air hose 20 Rails 21, 21a, 21b, 54 Stopper 22 Rotation drive unit 23 Holder 24 Rotating Plate 25 Rotating Shaft 26 Air Cylinder 30 Transfer Device 31 Frame Body 32 Drive Unit 33 Belt 34 Clean Room 35 Unidirectional Flow 36 Workers 40, 41, 42 Transfer Device 51 Silicon Wafer

Claims (6)

[Claims] 1. A plurality of air-permeable ceramic materials dispersedly arranged in accordance with the shape of an object to be conveyed, gas supply means for ejecting gas upward through the air-permeable ceramic material, and air-jetting from the air-permeable ceramic material. A holding mechanism that holds a transported object that floats by gas at a fixed position,
A transfer device comprising: a moving mechanism that moves the gas supply unit and the holding mechanism. 2. The gas supply means according to claim 1, further comprising: a gas supply pipe arranged substantially parallel to each other, and a gas outlet formed in the gas supply pipe, on which the gas permeable ceramic material can be mounted. Transport device. 3. The holding mechanism includes a plurality of breathable ceramic materials dispersedly arranged around the transported object, and gas supply means for ejecting gas toward the transported object through the breathable ceramic material. Claim 1 or 2 provided with
The transport device described. 4. The transfer device according to claim 1, wherein the moving mechanism moves the gas supply means and the holding mechanism in parallel and rotationally. 5. The porosity of the breathable ceramic material is 3
It is 0% -50%, The conveyance apparatus of Claims 1-4. 6. The conveying device according to claim 1, wherein the air-permeable ceramic material is a porous sintered body containing alumina and any one or more of silica, titania, magnesia, calcia, and yttria.