JP4349101B2 - Substrate transfer device - Google Patents

Description

  The present invention relates to a substrate transport apparatus that transports while supporting both side edge portions and bottom surface center portion of a thin plate substrate such as glass for liquid crystal in contact and non-contact, respectively.

For example, as a conveyor (substrate transport device) for transporting a glass substrate or the like used for manufacturing a liquid crystal display panel, a conveyor that transports while supporting both the lower side edges and the lower center of the glass substrate in contact and non-contact, respectively, is known. ing.
For example, as shown in Patent Documents 1 to 3, this type of conveyor is provided with a step between the conveyance roller and the gas floating portion, and deposits a part of the substrate's own weight on the conveyance roller. The power is secured.
JP 2001-196438 A JP 2003-063643 A JP-A-10-110891

However, as the glass substrate, which is a conveyed product, becomes larger and thinner, it has become difficult to obtain the frictional force necessary for conveyance only by the weight of the substrate, and the acceleration / deceleration during conveyance is limited. There is.
On the other hand, the required frictional force can be ensured by increasing the level difference between the transport roller and the gas floating part, but as the level difference increases, the warp of the part not supported by the transport roller and the gas floating part (deflection deformation due to drooping) ) Increases, and there is a problem that there is a concern about adverse effects on the substrate.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to carry the substrate without deforming it and to shorten the carrying time.

  In order to solve the above-described problems, the present invention arranges a plurality of pairs of transport rollers at intervals in a direction intersecting the transport direction so as to respectively support both side edges of the lower surface of the substrate. An air levitation unit that supports the lower surface central portion of the substrate in a non-contact manner is provided, and in the substrate transport apparatus that transports the substrate in the transport direction by rotating the transport roller, the substrate is biased toward the transport roller A means that an urging means is provided is employed.

It is also possible to adopt a means in which the urging force by the urging means acts in pairs in the vicinity of the transport roller, particularly on the inner side and the outer side of the substrate across the transport roller.
The biasing means may be configured to include a suction hole formed in the air levitation unit and a suction source connected to the suction hole.

According to the above means, the pressing force from the substrate to the transport roller not only applies the load on the transport roller when the weight of the substrate is borne by the transport roller and the air levitation unit, but also applies the biasing means to this. It becomes the thing which added power.
As a result, the frictional force generated between the substrate and the transport roller is increased, and the acceleration / deceleration during transport can be set larger than the conventional one, so that the substrate can be transported without causing deformation even if the substrate is enlarged. The conveyance time can also be shortened.

Further, when increasing the frictional force between the substrate and the transport roller, it is possible to balance the urging force acting on the inner side and the outer side of the transport roller while suppressing deformation at the central portion in the width direction of the substrate.
Furthermore, since a part of the urging means is incorporated in the existing air levitation unit, the entire apparatus can be reduced in size.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments which are the best mode of the present invention will be described below with reference to the drawings of FIGS.
The substrate transfer apparatus according to this embodiment is a large and thin plate like a glass substrate used in a liquid crystal display panel (LCD), a plasma display panel (PDP), etc. It is suitable for transporting what is required to be transported while supporting both side edges. As shown in FIG. 1, the transport roller unit 1 and the air floating unit 2 are provided.

  As shown in FIG. 3, the transport roller unit 1 is opposed to the width direction of the glass substrate 3 as a transported object, in other words, in the direction orthogonal to the transport direction of the glass substrate 3 (the white arrow in FIG. 2). A pair of frames 11 are provided, and a roller shaft 14 of a conveying roller 13 is rotatably supported on an upper end portion of the frames 11 via a shaft support 12 such as a bearing. The roller shafts 14 are provided in a plurality of rows at intervals in the conveyance direction of the glass substrate 3.

At one end (tip) of each roller shaft 14, there is provided a roller body 15 of a transport roller 13 that supports the glass substrate 3 by contacting the lower side edges (both ends in the width direction) 3a, 3b. A roller driving gear 16 that transmits a rotational driving force from a driving motor (not shown) to the roller shaft 14 is provided at the other end (base end) of each roller shaft 14.
The rotation of the drive motor is controlled based on a command from a control device (not shown).

The air levitation unit 2 supports the lower surface central portion 3 c of the glass substrate 3 in a non-contact manner, and includes a box-shaped chamber 21.
As shown in FIG. 2, a plurality of window portions 22 are formed through both ends of the chamber 21 in the width direction corresponding to the arrangement and the number of the roller main bodies 15, and the top portion 15A of the roller main body 15 is formed on the upper surface of the chamber. By positioning the substrate by an appropriate dimension above 21A, a part of the substrate weight is deposited on the transport roller 13, and the remaining weight is supported by the air floating unit 2 in a non-contact manner.

A gas blowing hole 23 and a suction hole 24 are formed in the chamber 21.
A large number of blowout holes 23 are formed at substantially equal intervals over the substantially entire surface of the chamber upper surface 21A so as to be arranged in, for example, a lattice shape or a staggered shape.
An air supply blower (not shown) is connected to the blowout hole 23 via a pipe line (not shown). When the air supply blower is driven based on a command from the control device, the chamber 21 passes through the pipe line. The gas fed to the substrate is injected toward the lower surface 3A of the substrate.

On the other hand, as shown in FIG. 3, the suction holes 24 are formed around the respective window portions 22 so as to be distributed inside and outside in the width direction of the chamber 21 with the respective window portions 22 interposed therebetween. That is, the suction holes 24 of this embodiment are formed only in the vicinity of the roller main body 15 and are arranged in pairs on the inner side and the outer side in the width direction of the glass substrate 3 with the roller main bodies 15 interposed therebetween. Further, the opening area of the suction hole 24 on the chamber upper surface 21 </ b> A is set to be larger than that of the blowout hole 23.
An intake blower (suction source) (not shown) is connected to the suction hole 24 via a pipe line (not shown). When the intake blower is driven based on a command from the control device, an arrow in FIG. The suction force shown acts on the glass substrate 3, and the glass substrate 3 is attracted downward. That is, the glass substrate 3 is urged toward the conveyance roller 13 side.

In the substrate transport apparatus configured as described above, when the drive motors rotate in synchronization, the rotational driving force is transmitted to the roller shaft 14 via the roller drive gear 16, and the transport rollers 13 are aligned in one direction. Rotate to.
As a result, the glass substrate 3 transferred to the upstream side of the substrate transport apparatus is given a transport force forward in the transport direction by the frictional force generated by the contact with the transport roller 13 with respect to the lower surface 3A. And is continuously conveyed downstream thereof.

At this time, the lower side edge portions 3a and 3b of the glass substrate 3 are supported from below by the conveying roller 13 which is in rolling contact therewith.
Further, by operating the air supply blower and pumping gas to the chamber 21 through the pipe line, the compressed air is jetted from the blowout hole 23 toward the substrate lower surface 3A. An air floating layer 25 is formed between the glass substrate 3 and the central portion in the width direction of the glass substrate 3 via the air floating layer 25 in a non-contact manner.

Furthermore, in the substrate transfer apparatus according to this embodiment, the suction blower is operated, and the gas is sucked from the suction hole 24 of the chamber 21 through the pipe line. Since both sides (width direction inner side portion and outer side portion) 5a and 5b of the portion 4 supported by the transport roller 13 are sucked, both lower side edges 3a and 3b of the glass substrate 3 are placed on the transport roller 13 side. Has been attracted.
As a result, the frictional force generated by the contact of the transport roller 13 with the substrate lower surface 3 </ b> A is larger than that when the weight of the substrate is simply borne by the transport roller 13 and the air floating unit 2.

That is, when the pressing force from the glass substrate 3 to the transport roller 13 that determines the magnitude of the frictional force generated between the glass substrate 3 and the transport roller 13 bears the weight of the substrate between the transport roller 13 and the air floating unit 2. In addition to the burden of the conveying roller 13 in FIG. 1, the pulling force by suction of the substrate from the suction hole 24 is added thereto.
For this reason, it is possible to ensure a sufficient and sufficient frictional force for transporting the substrate without increasing the step between the transport roller 13 and the chamber upper surface 21A and increasing the burden of the substrate's own weight by the transport roller 13. The acceleration / deceleration at the time of conveyance can be set larger than the conventional one.

  As described above, according to the substrate transfer apparatus of this embodiment, in recent years, a glass substrate 3 (for example, 1850 mm long × 1500 mm wide, 0.7 mm thick) that has been significantly increased in size and thickness has been transferred. However, the glass substrate 3 can be transported without being deformed (warped), or even if deformed, while suppressing deformation within a range that does not adversely affect the glass substrate 3, and the transport time can be shortened. There is an effect that it can be achieved.

  Further, since the suction holes 24 are formed only in the vicinity of the transport rollers 13 and are arranged so as to form a pair on the inner side and the outer side in the width direction of the glass substrate 3 with the transport rollers 13 interposed therebetween, The frictional force generated between the glass substrate 3 and the transport roller 13 is increased while balancing the urging force acting on the inner side and the outer side in the substrate direction rather than the transport roller 13 while suppressing deformation (warpage) in the central portion in the width direction. There is also an effect that can be done.

In addition, this invention is not limited to the said Example, A various design change is possible in the range which does not deviate from the summary.
For example, the urging force for urging the glass substrate 3 toward the transport roller 13 may be based on a gas blowing output from the substrate upper surface side instead of the gas suction force from the substrate lower surface 3A side.
Further, the formation position of the suction hole 24 is not limited to the periphery of the transport roller 13, and may be formed at other positions instead of or in addition to the position.

It is a front view of the board | substrate conveyance apparatus by one Example of this invention. It is a top view of the board | substrate conveyance apparatus shown in FIG. It is a principal part enlarged view of FIG. It is the further principal part enlarged view of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Conveyance roller unit 2 Air floating unit 3 Glass substrate 3a, 3b Lower side edge part 3c Lower surface center part 13 Conveyance roller 24 Suction hole (a part of biasing means)

Claims (3)

A plurality of pairs of transport rollers are arranged at intervals in the direction crossing the transport direction so that both side edges of the bottom surface of the substrate can be supported, and the center of the bottom surface of the substrate is supported in a non-contact manner between these transport rollers. In the substrate transport apparatus that includes the air levitation unit that transports the substrate in the transport direction by rotating the transport roller,
A substrate comprising a suction hole formed in the air levitation unit and a suction source connected to the suction hole, and provided with a biasing means for biasing the substrate toward the transport roller. Conveying device. 2. The substrate transfer apparatus according to claim 1, wherein an urging force by the urging unit acts on the transfer roller .   3. The substrate transfer apparatus according to claim 2, wherein the biasing force acts in a pair on the inner side and the outer side in the width direction of the substrate across the transfer roller.

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