Abstract:
A transfer apparatus is provided for the transport of transfer objects such as glass substrates or semiconductor devices in which cleanliness and secure transport are of major concern. A plurality of air nozzles inject air through the plurality of air nozzles to hold a transfer object in place above or below the plurality of air nozzles without the plurality of air nozzles making contact with the transfer object. The plurality of air nozzles are positioned perpendicular to the transfer object to stop and/or engage the transfer object in a rest position. The plurality of air nozzles are inclined to a specified angle to move the transferred object in a desired direction. Advantageously, because the transfer object is moved without physical contact between the structure of the air nozzles and the transfer object, the transfer is secure, clean, and efficient.

Description:
BACKGROUND 
   (a) Field of the Invention 
   The present invention relates to a transfer apparatus, and particularly to a transfer apparatus for transferring a large size glass substrate. 
   (b) Description of Related Art 
   In general, a transfer system or apparatus utilizes a conveyor apparatus to move a transfer object by placing the transfer object onto a conveyor which works in conjunction with an operating roller connected to an operating motor. 
   The conventional conveyor system uses the operating motor to provide power to move the transfer object and a chain, a gear, or a belt for the purpose of power transfer. Disadvantageously, the belt or chain may break or wear out causing maintenance problems and manufacturing delay. 
   Furthermore, since dust is generated due to the driving of a motor, the motor is arranged apart from the remainder of the conveyor system so as not to affect the transfer objects, such as semiconductor devices or liquid crystal displays (“LCDs”), in which cleanliness is an important issue. Therefore, because the motor is isolated from the place where the object is transferred, the operation is made more difficult, the system is more complicated, and the cost is increased. 
   Dust problems also arise with the use of gears. For a conventional apparatus, since one motor should drive a plurality of driving axes, a medium for transferring power, such as a gear, is required between each driving axes, which causes the dust problems indicated above. 
   If a motor and a conveyor belt are used, a noise problem also arises. The noise from machinery disturbs the operator or administrator, which decreases operation efficiency. 
   A transfer system or apparatus can be utilized to transfer glass substrates used in manufacturing liquid crystal displays (“LCDs”). An LCD is one of the most popular flat panel displays, which includes two panels provided with two kinds of electrodes generating an electric field and a liquid crystal layer interposed therebetween. The LCD displays images by controlling light transmittance, and the control of the light transmittance is performed by applying voltages to the electrodes to generate electric fields which change the arrangement of liquid crystal molecules. 
   The panels of an LCD can be transferred to processing devices used in the manufacturing process by using the transfer system. Conventionally, a plurality of glass substrates are transferred to a processing device using a cassette, a stocker, and an indexer. However, as glass substrates are getting larger, the conventional transfer system using the cassette, stocker, and indexer becomes harder to use and manage due to inflexibility and unwieldiness. 
   Various conventional transfer apparatuses such as conveyors, robots, stockers, AGVs (automatic guided vehicles), etc. have been enlarged in order to accommodate enlarged glass substrates. However, disadvantages remain with conventional systems and apparatus, such as generation of static electricity, decreased yield accompanied by contamination, and generation of cracks due to the contact between the glass substrate and the conveyor belt. Thus, there is a need in the art for a transfer apparatus that is flexible and clean and that transports objects securely without damage. 
   SUMMARY 
   The present invention provides an advantageous apparatus for transferring fragile objects, such as glass substrates used in the manufacture of LCDs, in which cleanliness and secure transport are of high concern. A plurality of air nozzles are used to transport glass substrates without making direct contact between the air nozzle structure and the substrate, thereby allowing for clean and secure transport of the substrate. 
   According to one embodiment of the present invention, a transfer apparatus is provided, including a panel, and a plurality of air nozzles operably coupled to the panel. The plurality of air nozzles can inject air to hold a transfer object in place above the plurality of air nozzles without the plurality of air nozzles making contact with the transfer object. 
   According to another embodiment of the present invention, another transfer apparatus is provided, including a connection body operably coupled to a guide line. A panel section is operably coupled to the connection body, and a plurality of air nozzles is operably coupled to the panel section. The plurality of air nozzles can inject air to hold a transfer object in place without the plurality of air nozzles making contact with the transfer object. 
   According to yet another embodiment of the present invention, another transfer apparatus is provided, including a panel, and a plurality of air nozzles operably coupled to the panel, wherein the plurality of air nozzles inject air while simultaneously providing suction to hold a transfer object in place without the plurality of air nozzles making contact with the transfer object. 
   Advantageously, the present invention allows for the secure and clean transport of glass substrates and other fragile objects, resulting in higher yields with less damage and contamination. The present invention also is advantageous to reduce noise while increasing transfer speed. 
   These and other features and advantages of the present invention will be more readily apparent from the detailed description of the embodiments set forth below taken in conjunction with the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a transfer apparatus according to a first embodiment of the present invention showing a state in which a glass substrate is stopped; 
       FIG. 2  is a sectional view of the transfer apparatus shown in  FIG. 1  taken along the line II–II′; 
       FIG. 3  is a perspective view of a transfer apparatus according to the first embodiment of the present invention showing a state in which a glass substrate is being transferred; 
       FIG. 4  is a sectional view of the transfer apparatus shown in  FIG. 3  taken along the line IV–IV′; 
       FIG. 5  is a perspective view of a transfer apparatus according to the first embodiment of the present invention showing a state in which a glass substrate is stopped at a branch point; 
       FIGS. 6A and 6B  are sectional views of the transfer apparatus shown in  FIG. 5  taken along the lines VIA–VIA′ and VIB–VIB′, respectively; 
       FIG. 7  is a perspective view of a transfer apparatus according to the first embodiment of the present invention showing a state in which a glass substrate is moved from a branch point to a branch direction; 
       FIG. 8  is a sectional view of the transfer apparatus shown in  FIG. 7  taken along the lines VIII–VIII′; 
       FIG. 9  is a perspective view of a transfer apparatus according to a second embodiment of the present invention; 
       FIG. 10  is a lateral view of the transfer apparatus shown in  FIG. 9 ; 
       FIG. 11  is a perspective view of a transfer apparatus according to a third embodiment of the present invention; 
       FIG. 12  is a lateral view of the transfer apparatus shown in  FIG. 11 ; and 
       FIG. 13  is a perspective view of an embodiment of an air transfer groove formed inside an air nozzle. 
   

   Use of the same reference symbols in different figures indicates similar or identical items. It is further noted that the drawings may not be drawn to scale. 
   DETAILED DESCRIPTION 
   The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. 
   In the figures, the thickness of layers and regions are exaggerated for clarity. Like numerals refer to like elements throughout. It will be understood that when an element such as a layer, region, or substrate is referred to as being “on” another element, the element can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. 
   A transfer apparatus according to preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings. 
     FIGS. 1–8  and  13  illustrate a transfer apparatus according to a first embodiment of the present invention.  FIG. 1  is a perspective view of an example of the transfer apparatus showing a state in which a glass substrate is stopped.  FIG. 2  is a sectional view of the transfer apparatus shown in  FIG. 1  taken along the line II–II′,  FIG. 3  is a perspective view of an example of the transfer apparatus showing a state in which the glass substrate is being transferred.  FIG. 4  is a sectional view of the transfer apparatus shown in  FIG. 3  taken along the line IV–IV′.  FIG. 5  is a perspective view of an example of the transfer apparatus showing a state in which the glass substrate is stopped at a branch point.  FIGS. 6A and 6B  are sectional views of the transfer apparatus shown in  FIG. 5  taken along the lines VIA–VIA′ and VIB–VIB′, respectively.  FIG. 7  is a perspective view of an example of the transfer apparatus showing a state in which the glass substrate is transferred from a branch point to a branch direction.  FIG. 8  is a sectional view of the transfer apparatus shown in  FIG. 7  taken along the lines VIII–VIII′.  FIG. 13  illustrates a perspective view of an embodiment of an air transfer groove formed inside an air nozzle. 
   Referring now to  FIGS. 1 and 2 , a transfer apparatus includes a support panel  10  and a plurality of air nozzles  20  that are formed on the support panel  10  for transferring a transfer object  30 , in one example a glass substrate.  FIGS. 1 and 2  illustrate transfer object  30  at a rest position. 
   The support panel  10  is arranged along the transfer direction of transfer object  30 . In other words, support panel  10  is installed along desired transfer directions for the transfer object, for example along a transfer direction A of transfer object  30  and also along a branch direction B ( FIGS. 7 and 8 ) in which transfer object  30  is carried after being branched off at a branch point of support panel  10 . The plurality of air nozzles  20  formed on support panel  10  are arranged along direct transfer direction A and also along branch direction B. When transfer object  30  is carried, air nozzles  20  are placed under the transfer object  30 . 
   As can be seen in  FIG. 2 , air nozzles  20  are in a perpendicular configuration such that air nozzles  20  inject air in a perpendicular direction relative to transfer object  30  and support panel  10 . The physical structure of air nozzles  20  and transfer object  30  do not come into contact with one another. Instead, air nozzles  20  are placed to maintain a prescribed distance between transfer object  30  and each of the plurality of air nozzles  20 . In order to accomplish this, the plurality of air nozzles  20  fix the position of transfer object  30  by injecting air and forming a vacuum status inside each of the plurality of air nozzles  20  to prevent transfer object  30  from straying by the injection of air. In other words, at each air nozzle, there is simultaneous air injection impinging on the surface of the transfer object and a vacuum or suction effect, similar to a whirlpool&#39;s center, and thus the air injection “sticks” to the transfer object, thereby stabilizing the position of the transfer object. 
     FIG. 13  is a perspective view of a section of an air transfer groove  21  formed inside an air nozzle  20  to form a vacuum status inside each of the plurality of air nozzles  20 . Air transfer groove  21  can be formed to have various forms for creating simultaneous air injection and suction. In one example, air transfer groove  21  can be formed to be slanted or spiral in shape. 
   Referring now to  FIGS. 3 and 4 , an example is illustrated of transfer object  30  being moved or transferred in direction A. The plurality of air nozzles  20  are formed such that inclination of air nozzles  20  relative to the transfer direction can be controlled.  FIG. 4  illustrates air nozzles  20  making a specified angle θ with reference to the transfer direction of transfer object  30 , in one example direction A. 
   Control over the inclination of air nozzles  20  in conjunction with pressure of the air injection directs the transfer or movement of transfer object  30 . If transfer direction A of transfer object  30  and the inclination of air nozzle  20  make up an angle over 0 degrees and under 90 degrees in an up and down direction, transfer object  30  would be transferred forward. If transfer direction A of transfer object  30  and the inclination of air nozzle  20  make up an angle over 90 degrees and under 180 degrees in an up and down direction, transfer object  30  would be transferred backward. Referring to  FIG. 2 , if transfer direction A of transfer object  30  and the inclination of air nozzle  20  make up an angle of 90 degrees, transfer object  30  would be stopped. Transfer speed of transfer object  30  can be controlled by controlling pressure and direction of the air injected via air nozzles  20 . 
   Advantageously, since the plurality of air nozzles  20  and transfer object  30  are not in contact with one another but maintain a prescribed distance with each other, the transfer speed is enhanced, no noise is generated, and the transfer object is transferred without damage. Distance between air nozzles  20  and transfer object  30  is preferably between about 10 μm and about 30 μm. 
   As noted previously, the plurality of air nozzles  20  are formed to be able to make a specified angle in up and down or back and forth directions with reference to the transfer direction of transfer object  30 . Referring now to  FIGS. 5 ,  6   a,  and  6   b,  a certain set of air nozzles  20 ′ can form a perpendicular or 90 degree angle with reference to the transfer direction of transfer object  30  when stopping and/or changing the direction of transfer object  30  at a branch point in support panel  10 . Thus, some air nozzles may operate independently from one another so as to be inclined at different angles or operate with different air injection pressures in order to stop and/or change the direction of transfer object  30  during transport. 
   As shown in  FIGS. 7 and 8 , when transfer object  30  arrives at a branch point and is stopped, the plurality of air nozzles  20 ′ switch their inclination to branch direction B to direct transfer object  30  along the branch support panel  10  in branch direction B. Transfer object  30  can be transferred to branch direction B by switching the direction of air nozzles  20 ′ to make an angle over 0 degrees and under 90 degrees in left and right directions with reference to the transfer direction of transfer object  30 . 
   The operation of the transfer apparatus according to an embodiment of the present invention having a structure as described above will now be described. 
   First, as shown in  FIGS. 1 and 2 , the plurality of air nozzles  20  engage transfer object  30  without contacting transfer object  30  with the physical structure of air nozzles  20  by injecting air. Since the plurality of air nozzles  20  are inclined 90 degrees, transfer object  30  is not moving or being transferred and is instead in a rest position. 
   Next, as shown in  FIGS. 3 and 4 , the plurality of air nozzles  20  are inclined to have a specified angle in up and down directions with reference to direct transfer direction A of transfer object  30 . The inclination of air nozzles  20  also directs the air injection from the plurality of air nozzles  20  such that transfer object  30  slides in direct transfer direction A. 
   Advantageously, the present invention does not require a separate driving motor or driving roller. Since the physical structures of air nozzles  20  and transfer object  30  do not come into contact with one another but instead maintain a prescribed distance from one another, there is no power loss due to friction thereby enhancing the transfer speed and no contact noise is generated. 
   Subsequently, as shown in  FIGS. 5 ,  6 A, and  6 B, when transfer object  30  arrives at the branch point, the plurality of air nozzles  20 ′ stop transfer object  30  by being positioned such that air nozzles  20 ′ make a 90 degree angle relative to the transfer direction of transfer object  30 . Preferably, a separate stopping pin  40  is used as well to stop transfer object  30  at the branch point. 
   Succeedingly, as shown in  FIGS. 7 and 8 , when transfer object  30  is stopped after arriving at the branch point, the plurality of air nozzles  20 ′ are inclined toward branch direction B. The inclination of air nozzles  20 ′ also directs the air injection from the plurality of air nozzles  20 ′ such that transfer object  30  slides in branch direction B. Advantageously, since transfer object  30  can be branched off by simply switching the direction of a certain set of air nozzles  20 ′, a separate feeder for branching off is not needed, and problems with slow transfer speed at branch points can be resolved. 
     FIG. 9  is a perspective view of a transfer apparatus according to a second embodiment of the present invention, and  FIG. 10  is a lateral view of the transfer apparatus shown in  FIG. 9 . The same reference numerals in the drawings mentioned above indicate similar parts for performing similar functions. 
   As shown in  FIGS. 9 ,  10 , and  13 , a transfer apparatus according to the second embodiment of the present invention includes a support panel  10  operably coupled to a transfer means  50  for transferring a transfer object  30 . Transfer means  50  includes a connection body  51  and a guide line  52  on which connection body  51  is operably coupled and moved by sliding. 
   A plurality of air nozzles  20  are arranged on support panel  10 , and in a similar manner as described above with respect to the first embodiment, the plurality of air nozzles  20  fix the position of transfer object  30  by injecting or sucking air to form a vacuum status inside each of the plurality of air nozzles  20  while maintaining a specified distance with transfer object  30 . In other words, the physical structures of air nozzles  20  and transfer object  30  do not come into contact with one another and maintain a prescribed distance from one another. In order to do that, air nozzles  20  fix the position of transfer object  30  by injecting air and forming a vacuum status inside each of the plurality of air nozzles  20  to prevent transfer object  30  from straying by the injection of air. 
   Referring again to  FIG. 13 , an air transfer groove  21  is formed inside each air nozzle  20  to form a vacuum status inside air nozzle  20 . Air transfer groove  21  can be formed into various forms such as slanted or spiral shapes. 
   Accordingly, as connection body  51  is moved along guide line  52 , coupled support panel  10  also moves along guide line  52 , thus moving transfer object  30  which is fixed to air nozzles  20  arranged on support panel  10 . 
   The operation of the transfer apparatus according to the second embodiment of the present invention having a structure as described above will now be described. 
   First, transfer object  30  is fixed by a plurality of air nozzles  20  placed on support panel  10  to have a specified distance between the air nozzles and the transfer object. 
   Next, transfer object  30  is transferred by transfer means  50  connected to the support panel  10 . 
   Advantageously, it is possible to transfer transfer object  30  without contacting a pattern portion of an LCD formed on transfer object  30 . Furthermore, when the transfer object has to be moved along a different direction, the transfer object may be simply transferred to the other direction by rotating transfer means  50 . 
   It is also possible to pick up and transfer the transfer object  30  from above as is described in a third embodiment below. 
     FIG. 11  is a perspective view of a transfer apparatus according to the third embodiment of the present invention, and  FIG. 12  is a lateral view of the transfer apparatus shown in  FIG. 11 . The same reference numerals as in drawings mentioned above indicate similar parts for performing similar functions. 
   As shown in  FIGS. 11 ,  12 , and  13 , a transfer apparatus according to the third embodiment of the present invention includes a support panel  10  and a transfer means  50  for transferring the support panel  10 . Transfer means  50  includes a connection body  51  connected to a top portion of support panel  10  and a guide line  52  on which connection body  51  is operably coupled and moved by sliding. 
   A plurality of air nozzles  20  are arranged under support panel  10 , and the plurality of air nozzles  20  fix the position of transfer object  30  by injecting or sucking air while maintaining a specified distance with transfer object  30 . In other words, the plurality of air nozzles  20  and transfer object  30  are not contacted but placed to maintain a prescribed distance with each other. In order to do that, air nozzles  20  fix the position of transfer object  30  by injecting air and forming a vacuum status inside each of the plurality of air nozzles  20  to prevent transfer object  30  from straying by the injection of air. 
   Referring again to  FIG. 13 , an air transfer groove  21  is formed inside each air nozzle  20  to form a vacuum status inside air nozzle  20 . Air transfer groove  21  can be formed to have various forms, such as slanted or spiral shapes. 
   Accordingly, as connection body  51  moves along guide line  52 , coupled support panel  10  also moves along guide line  52 , thus moving transfer object  30  which is fixed to air nozzles  20  arranged on support panel  10 . 
   The operation of the transfer apparatus according to the third embodiment of the present invention having a structure as described above will now be described. 
   First, transfer object  30  is fixed by the plurality of air nozzles  20  placed under support panel  10  to have a specified distance between air nozzles  20  and transfer object  30 . 
   Next, the transfer object  30  is transferred by transfer means  50  connected to the support panel  10 . 
   Advantageously, it is possible to transfer transfer object  30  without contacting a pattern portion of an LCD formed on transfer object  30 . Furthermore, when the transfer object has to be rotated to be transferred to another direction, the transfer object can be simply transferred to the other direction by rotating transfer means  50 . 
   Since the present invention transfers the transfer object, in one example a glass substrate, by only using air, the structure of the apparatus becomes simple and investment cost for the initial manufacturing processing device is reduced because a stocker, a cassette, and/or an indexer are not used. 
   Moreover, yield is enhanced by preventing breaking or cracks due to contact and by preventing chemical or particle contamination by providing transfer of the glass substrate without contacting the glass substrate with the air nozzles. 
   In addition, since the glass substrate is transferred without friction, the transfer speed is enhanced and the time required for transfer is shortened. 
   Furthermore, because the glass substrate is transferred only using air, the problem of transfer delay upon changing the transfer direction, for example when the glass substrate is rotated, branched off, joined together, or buffered, is resolved. 
   Since a gear for connection between power axes, or a chain or a belt which is a medium of power transfer is not needed, noise due to the revolution of the motor and that due to tooth-setting of the gears for connection between power axes are reduced. 
   It will be apparent that the present invention may be used in conjunction with various processing apparatus in various manufacturing systems such as those described in co-pending U.S. patent application Ser. No. 10/863,064 with the same filing date which is incorporated by reference herein for all purposes. 
   Although preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that many variations and/or modifications of the basic inventive concepts herein taught which may appear to those skilled in the present art will still fall within the spirit and scope of the present invention, as defined in the appended claims.