U.S. patent application number 12/652069 was filed with the patent office on 2010-04-29 for levitation transportation device and levitation transportation method.
This patent application is currently assigned to Kabushiki Kaisha Watanabe SHOKO. Invention is credited to Masayuki TODA, Masaru UMEDA.
Application Number | 20100104380 12/652069 |
Document ID | / |
Family ID | 35776006 |
Filed Date | 2010-04-29 |
United States Patent
Application |
20100104380 |
Kind Code |
A1 |
TODA; Masayuki ; et
al. |
April 29, 2010 |
LEVITATION TRANSPORTATION DEVICE AND LEVITATION TRANSPORTATION
METHOD
Abstract
A levitation transportation device capable of adjustment when an
object being transported is displaced from the center of a
transportation path, A levitation transportation device having a
transportation path forming a transportation router for an object
to be transported, a plurality of jetting nozzles for transporting
the object in a levitated manner along the transportation path, one
or more detection sections for detecting the direction of the
transportation of the object being transported in the
transportation path and a control section for independently
controlling the plurality of jetting nozzles based on a detection
result by the detection sections.
Inventors: |
TODA; Masayuki;
(Yonezawa-shi, JP) ; UMEDA; Masaru; (Tokyo,
JP) |
Correspondence
Address: |
YOUNG & THOMPSON
209 Madison Street, Suite 500
Alexandria
VA
22314
US
|
Assignee: |
SHOKO; Kabushiki Kaisha
Watanabe
Tokyo
JP
TODA; Masayuki
Yonezawa-shi
JP
|
Family ID: |
35776006 |
Appl. No.: |
12/652069 |
Filed: |
January 5, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11630437 |
Mar 26, 2007 |
|
|
|
PCT/JP2005/011416 |
Jun 22, 2005 |
|
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12652069 |
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Current U.S.
Class: |
406/12 |
Current CPC
Class: |
H01L 21/67784 20130101;
B65G 51/03 20130101; B65G 47/24 20130101 |
Class at
Publication: |
406/12 |
International
Class: |
B65G 51/10 20060101
B65G051/10 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 28, 2004 |
JP |
2004-189444 |
Claims
1. A levitation transportation device, comprising: a transportation
path forming a transportation route for an object to be
transported; a plurality of jetting nozzles for transporting the
object in a levitated manner along the transportation path; at
least one detection section configured to detect a direction of the
object being transported in the transportation path; and a control
section for independently controlling the plurality of jetting
nozzles based on a detection result of the detection section.
2. The levitation transportation device according to claim 1,
further comprising: a line sensor having a detection range crossing
a direction of the transportation path and across an entire width
of the transportation path.
3. The levitation transportation device according to claim 1,
wherein the control section, based on the direction of the object
detected by the at least one detection section, controls a jetting
pressure of a pressure gas jetted from the jetting nozzles such
that the object being transported is returned to a center of the
transportation path.
4. The levitation transportation device according to claim 1,
wherein the control section, based on the direction of the object
detected by the at least one detection section, controls a jetting
pressure of the pressure gas jetted from the jetting nozzles such
that the object being transported is not displaced from a center of
the transportation path.
5. A levitation transportation method, comprising: transporting an
object using a levitation transportation device, the levitation
transportation device comprising a transportation path forming a
transportation route for an object to be transported, a plurality
of jetting nozzles for transporting the object in a levitated
manner along the transportation path, at least one detection
section configured to detect a direction of the transportation of
the object being transported in the transportation path, and a
control section for independently controlling the plurality of
jetting nozzles based on a detection result of the detection
section.
6. The method according to claim 5, wherein the levitation
transportation device further comprises a line sensor having a
detection range crossing a direction of the transportation path and
across an entire width of the transportation path.
7. The method according to claim 5, further comprising: controlling
a jetting pressure of a pressure gas jetted from the jetting
nozzles based on the direction of the object detected by the at
least one detection section so that the object being transported is
returned to a center of the transportation path.
8. The method according to claim 5, further comprising: controlling
a jetting pressure of a pressure gas jetted from the jetting
nozzles based on the direction of the object detected by the at
least one detection section so that the object being transported is
not displaced from a center of the transportation path.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a division of co-pending application Ser. No.
11/630,437 filed on Mar. 26, 2007, which is a National Stage of
PCT/JP2005/011416 filed on Jun. 22, 2005, which claims priority to
Japanese Application No. 2004-189444 filed on Jun. 28, 2004. The
entire contents of each of the above-identified applications are
hereby incorporated by reference.
TECHNICAL FIELD
[0002] The present invention relates to a levitation transportation
device for transporting a plate-state object to be transported by
jetting a pressure gas to the object being transported in a
levitated manner and a levitation transportation method using this
levitation transportation device.
BACKGROUND ART
[0003] Patent Document 1: Japanese Patent Laid-Open No.
2000-72250
[0004] A levitation transportation device has been known that an
object being transported such as a semiconductor wafer in a
molding/machining process is transported while being levitated by
jetting airflow (See Patent Document 1, for example).
[0005] This type of levitation transportation device performs
transportation while carrying out a molding/machining process at a
predetermined molding/machining stage by combining a transfer unit
and a control unit.
[0006] FIG. 6 shows a state where the semiconductor wafer as an
object to be transported is being transported in a part of such
transportation process, and a large number of jetting nozzles with
jetting ports opened on the surface are arranged laterally and
vertically on a back face of a transportation path 1 extending in a
predetermined direction. Also, a guard 3 rises on the sides of the
transportation path 1 in order to prevent removal of a
semiconductor wafer 2 from the transportation path 1 when the
semiconductor wafer 2 being transported is displaced from the
center of the transportation path 1.
[0007] FIG. 7 shows an example of a jetting nozzle for
levitating/transporting such semiconductor wafers. In FIG. 7, a
jetting nozzle 4 is a columnar body held by a holding hole 5a of a
holding plate 5 forming the transportation path 1, and a projecting
portion 4a is formed at a part thereof for positioning not being
capable of relative rotation by engaging a recess portion 5b formed
in the holding hole 5a. Also, the jetting nozzle 4 is provided with
a communication path 4b opened on the back face of the holding
plate 5 and a nozzle 4c penetrating from the upper end of this
communication path 4b to the upper end face in the inclined
state.
[0008] By this, a pressure gas supplied to the back face of the
holding plate 5 is jetted from the nozzle 4c through the
communication path 4b.
[0009] The inclination angle of the nozzle 4c, including a right
angle, is determined by a transportation direction and the like of
the semiconductor wafer 2.
DISCLOSURE OF INVENTION
Problem to be Solved by the Invention
[0010] In the above constructed levitation transportation device,
there is a problem that, since the jetting nozzle 4 is held at the
holding plate 5, not being capable of relative rotation, when the
semiconductor wafer 2 is displaced from the center of
transportation in the middle of the transportation, it can not be
corrected.
[0011] This displacement of the semiconductor wafer 2 from the
center of transportation is caused by a jetting direction or
pressure of the pressure gas jetted from the jetting nozzle 4 or by
flatness on the back face of the semiconductor wafer 2.
[0012] In order to solve the above problem, the present invention
has an object to provide a levitation transportation device capable
of adjustment when an object being transported is displaced from
the center of a transportation path and a levitation transportation
method.
Means for Solving Problem
[0013] In order to achieve the object, a levitation transportation
device described in a first embodiment comprises a transportation
path forming a transportation route for an object to be
transported, a plurality of jetting nozzles for transporting the
object in a levitated manner along the transportation path, one or
more detection sections for detecting the direction of the
transportation of the object being transported in the
transportation path, and a control section for independently
controlling the plurality of jetting nozzles based on a detection
result of the detection section.
[0014] The levitation transportation device described in a second
embodiment is characterized in that the control section controls a
jetting direction or jetting pressure of a pressure gas jetted from
the jetting nozzle based on the detection result of the detection
section.
[0015] The levitation transportation device described in a third
embodiment is characterized in that the control section
drive-controls a driving motor for rotating the jetting nozzle in
the same plane based on the detection result of the detection
section.
[0016] The levitation transportation device described in a fourth
embodiment is characterized in that the control section controls a
jetting direction or jetting pressure of the pressure gas jetted
from the jetting nozzle so that the object being transported is
returned to the center of the transportation path based on the
detection result of the detection section.
[0017] The levitation transportation device described in a fifth
embodiment is characterized in that the control section controls a
jetting direction or jetting pressure of the pressure gas jetted
from the jetting nozzle so that the object being transported is not
displaced from the center of the transportation path based on the
detection result of the detection section.
[0018] The levitation transportation device described in a sixth
embodiment is characterized in that the control section controls a
jetting direction or jetting pressure of the pressure gas jetted
from the jetting nozzle when a detection result that the object
being transported is displaced from the center of the
transportation path continuously in the same direction is obtained
from the detection section.
[0019] The levitation transportation device described in a seventh
embodiment is a line sensor having a detection range crossing the
transporting direction of the transportation path and across the
entire width of the transportation path.
[0020] A levitation transportation method described in an eighth
embodiment is characterized in that the object to be transported is
transported using the levitation transportation device described in
any one of the first through seventh embodiments.
EFFECT OF THE INVENTION
[0021] According to the levitation transportation device of the
present invention, adjustment can be made when the object being
transported is displaced from the center of the transportation
path.
BRIEF DESCRIPTION OF DRAWINGS
[0022] FIG. 1 is a plan view of an essential part of a levitation
transportation device of the present invention;
[0023] FIG. 2 is a sectional view of a jetting nozzle of the
levitation transportation device of the present invention;
[0024] FIG. 3 is a detection graph showing a proper transportation
state by a line sensor of the levitation transportation device of
the present invention;
[0025] FIG. 4 is a detection graph showing an improper
transportation state by a line sensor of the levitation
transportation device of the present invention;
[0026] FIG. 5 is a perspective view of a nozzle body of the
levitation transportation device of the present invention;
[0027] FIG. 6 is a plan view of an essential part of a conventional
levitation transportation device; and
[0028] FIG. 7 is a sectional view of a jetting nozzle of the
conventional levitation transportation device.
EXPLANATIONS OF LETTERS OR NUMERALS
[0029] 10: Levitation transportation device [0030] 11:
Transportation path [0031] 15: Jetting nozzle [0032] 20:
Transportation section [0033] 21: Base section [0034] 18: Nozzle
body
BEST MODES FOR CARRYING OUT THE INVENTION
[0035] Next, a levitation transportation device and a levitation
transportation method of the present invention will be described
based on the attached drawings.
[0036] FIG. 1 is a plan view of an essential part of the levitation
transportation device of the present invention, FIG. 2 is a
sectional view of a jetting nozzle of the levitation transportation
device, and FIG. 5 is a perspective view of a nozzle body.
[0037] In FIG. 1, a levitation transportation device 10 of the
present invention forms a transportation path 11 by arranging a
plurality of transfer units and control units laterally and
vertically in plural. The transfer units or the control units
constitute a predetermined transportation direction by arranging
them in plural and adjacent with each other, but arrangement can be
made freely, and only a part of straight-state arrangement is shown
here.
[0038] The levitation transportation device 10 has a guide 13
provided at both edge portions along the transportation path 11,
for preventing falling of a semiconductor wafer 12 as an object
being transported from the transportation path. Also, the
levitation transportation device 10 is provided with, as shown in
FIG. 2, a large number of jetting nozzles 15 arranged laterally and
vertically on the back face of a holding plate 14 forming the
transportation path 11 and a plurality of line sensors 16 crossing
the transportation direction of the transportation path 11 and
across the entire width of the transportation path 11.
[0039] The jetting nozzle 15 has a pressure gas supplied from a
pressure-gas supply source such as a compressor through a piping,
and a conventional construction is employed as the supply
structure. Also, the jetting nozzle 15 is provided with, as shown
in FIG. 2, a bracket 17 fixed to the holding plate 14 (or substrate
vertically opposed to the holding plate 14) through a frame or the
like, not shown, a nozzle body 18 rotatably held by this bracket
17, and a driving motor unit 19 for rotating the nozzle body
18.
[0040] The line sensors 16 are placed at appropriate plural
locations of the transportation path 11, and its detection result
is outputted to a control section 22. At this time, one line sensor
16 monitors one transportation position of the semiconductor wafer
12. For example, a notch 12a is formed at the semiconductor wafer
12 for positioning with a machine at various machining.
[0041] Therefore, as shown in FIG. 3, the position of this notch
12a is detected by two inter-peak positions, and if the two peaks
are located at an equal distance from the center of the line sensor
16, the control section 22 determines that the semiconductor wafer
12 is properly located at a transportation center Q of the
transportation path 11 while being transported.
[0042] On the contrary, as shown in FIG. 4, when the two peaks are
displaced from the center of the line sensor 16, the control
section 22 determines that the semiconductor wafer 12 is displaced
from the transportation center Q of the transportation path 11
while being transported.
[0043] The bracket 17 is provided with a communication path 17a
communicating with the piping connected form the pressure-gas
supply source, not shown, and a holding hole 17b for holding the
nozzle body 18. Also, a large-diameter portion 17c opened on the
upper face is formed at the upper end of this holding hole 17b. The
communication path 17a communicates with the holding hole 17b, but
a control valve such as an electromagnetic valve (three-way valve,
for example) may be interposed between the above-mentioned piping
and the communication path 17a.
[0044] The nozzle body 18 is, as shown in FIG. 5, integrally
provided with an annular recess portion 18b whose entire outer
circumference is recessed in the annular state, forming an annular
supply path 18a in cooperation with an inner wall of the holding
hole 17b, a communication hole 18c penetrating between the inner
wall faces of the annular recess portion 18b via the axis, a shaft
hole 18d formed on the axis of the nozzle body 18 and communicating
with the communication hole 18c, a nozzle 18e communicating with
the upper end of the shaft hole 18d and opened on the upper end
face of the nozzle body 18, and an annular flange portion 18f
engaged with the large-diameter portion 17c. The nozzle 18e is
formed in the perpendicular or inclined state with respect to the
nozzle body 18 as necessary (according to the installation place of
the transportation path 11). Also, the nozzle body 18 is formed by
casting or injection molding or the like and then, the
communication hole 18b is formed so as to penetrate between the
inner wall faces of the annular recess portion 18b, while the shaft
hole 18d is formed on the axis from the lower end face of the
nozzle body 18, and then, the nozzle 18e is drilled. By this, the
lower part from the communication hole 18b of the shaft hole 18d is
sealed by a packing 20.
[0045] The driving motor unit 19 rotation-controls the nozzle body
18 in order to adjust the orientation of the nozzle 18e when the
nozzle body 18 is mounted at the bracket 17. The driving motor unit
19 also rotation-controls the position of the nozzle body 18
according to a determination result of the control section based on
a detection signal from the line sensor 16.
[0046] In the above construction, when the control valve such as a
compressor is driven, the pressure gas is jetted from the nozzle
18e through the communication path 17a, the supply path 18a
(annular recess portion 18b), the communication hole 18c and the
shaft hole 18d in this order.
[0047] At this time, since the nozzle body 18 is capable of
rotation on the horizontal plane by the driving motor unit 19, the
jetting direction of the pressure gas jetted from the nozzle 18e
can be adjusted.
[0048] Also, when the semiconductor wafer 12 is displaced from the
transportation path 11 while being transported, the displacement
position and the displacement amount are detected by the line
sensor 16, and based on the detection result, the control section
22 controls the driving motor unit 19 and rotates the nozzle body
18 to change the jetting direction from the nozzle 18e so as to
return the semiconductor wafer 12 to a proper position.
[0049] When the semiconductor wafer 12 is being transported, two
types of transportation displacement can be considered.
[0050] That is, one of the causes of the transportation
displacement might be that depending on the processing process of
the semiconductor wafer 12, there might be irregularity such as
sags by the unit of micrometer formed on the back face on the
transportation side of the semiconductor wafer 12, that is, on the
surface to which the pressure gas jetted from the nozzle 18e is
jetted, and the transportation position of the semiconductor wafer
12 is displaced by this irregularity.
[0051] And this type of displacement is given transportation
position modification per semiconductor wafer 12 based on the
above-mentioned detection result of the displacement position and
the displacement amount by the line sensor 16.
[0052] On the other hand, if the installation position of the
nozzle body 18, that is, the jetting direction of the nozzle 18e is
not appropriate, the displacement in the transportation direction
of the semiconductor wafer 12 might also occur.
[0053] The displacement in this case is considered to occur by the
same amount in the same direction continuously, and if this type of
displacement occurs, the position of the nozzle body 12 is modified
so that the semiconductor wafer 12 is transported appropriately
based on the above-mentioned detection result of the displacement
position and the displacement amount by the line sensor 16.
INDUSTRIAL APPLICABILITY
[0054] According to the levitation transportation device of the
present invention, adjustment can be made when an object being
transported is displaced from the center of a transportation
path.
* * * * *