U.S. patent application number 09/811473 was filed with the patent office on 2002-09-26 for module cover assembly with door latch transmission mechanism for wafer transport module.
Invention is credited to Chen, Jone Nan, Hsieh, Chang Yu.
Application Number | 20020134784 09/811473 |
Document ID | / |
Family ID | 25206638 |
Filed Date | 2002-09-26 |
United States Patent
Application |
20020134784 |
Kind Code |
A1 |
Hsieh, Chang Yu ; et
al. |
September 26, 2002 |
MODULE COVER ASSEMBLY WITH DOOR LATCH TRANSMISSION MECHANISM FOR
WAFER TRANSPORT MODULE
Abstract
A module cover is equipped with at least one door latch
transmission mechanism for closing the entrance of a wafer
transport module, each door latch transmission mechanism includes a
door latch supported on a roller at the module cover, a latch bolt
pivotally coupled between one end of the door latch and a part of
the module cover, and a driving wheel coupled to the module cover
and rotated to move the door latch forwards and backwards and to
further turn the latch bolt in and out of a through hole on the
module cover and a respective latch hole on the wafer transport
module to lock/unlock the module cover.
Inventors: |
Hsieh, Chang Yu; (Taichung
Hsien, TW) ; Chen, Jone Nan; (Kingmen, TW) |
Correspondence
Address: |
ROSENBERG, KLEIN & LEE
3458 ELLICOTT CENTER DRIVE-SUITE 101
ELLICOTT CITY
MD
21043
US
|
Family ID: |
25206638 |
Appl. No.: |
09/811473 |
Filed: |
March 20, 2001 |
Current U.S.
Class: |
220/323 ;
292/66 |
Current CPC
Class: |
H01L 21/67373 20130101;
Y10T 292/089 20150401 |
Class at
Publication: |
220/323 ;
292/66 |
International
Class: |
B65D 045/28 |
Claims
What is claimed is:
1. A module cover assembly comprising a module cover adapted to
close the entrance of a wafer transport module, said module cover
comprising at least one through hole on an upright peripheral wall
thereof respectively aimed at a respective latch hole on the wafer
transport module with which said module cover is used, and at least
one door latch transmission mechanism installed in said module
cover and respectively moved in and out of said at least one
through hole of said module cover and a respective latch hole on
the wafer transport module with which said module cover is used to
lock/unlock said module cover, wherein said at least one door latch
transmission mechanism each comprises: a driving wheel, said
driving wheel comprising a protruded center mount adapted to
receive handle means at the wafer transport module with which said
module cover is used, for enabling said driving wheel to be rotated
through which said handle means, and at least one smoothly arched
eccentric guide slot; a door latch, said door latch comprising a
front end, a rear end, a front notch disposed at said front end,
and a coupling rod disposed at said rear end and coupled to one
smoothly arched eccentric guide slot of said driving wheel for
enabling said door latch to be moved forwards and backwards between
the locking position and the unlocking position; and a latch bolt
coupled to the front end of said latch bolt and moved with said
latch bolt in and out of one of said at least one through hole of
said module cover and the corresponding latch hole on the wafer
transport module with which said module cover is used to
lock/unlock said module cover, said latch bolt comprising a bottom
lug inserted into the front notch of said door latch and pivotally
connected to the front end of said door latch by a pivot, a top
coupling block pivotally connected to a part of the module cover by
a pivot, and a front retaining block adapted for moving in and out
of one of said at least one through hole of said module cover and
the corresponding latch hole on the wafer transport module with
which said module cover is used to lock/unlock said module
cover.
2. The module cover of claim 1 wherein said at least one door latch
transmission mechanism each further comprises a cylindrical roller
revolvably coupled to the respective driving wheel by a pivot to
support the rear end of said door latch on said module cover and to
guide movement of said door latch on said module cover.
3. The module cover of claim 1 wherein said at least one door latch
transmission mechanism each further comprises a cushion cap
revolvably capped on the coupling rod of the respective door latch
and inserted with the coupling rod of the respective door latch
into one eccentric guide slot of the respective driving wheel.
4. The module cover of claim 1 wherein the front retaining block of
the latch bolt of each of said at least one door latch transmission
mechanism has a sector-like cross section.
5. The module cover of claim 1 further comprising handle means
disposed outside said module cover and respectively coupled to the
center mount of the driving wheel of each of said at least one door
latch transmission mechanism for operation by hand to rotate the
driving wheel of each of said at least one door latch transmission
mechanism.
6. The module cover of claim 1 wherein said module cover comprises
upright support means adapted to support the pivot at top coupling
block of the latch bolt of each of said at least one door latch
transmission mechanism.
7. A module cover assembly comprising a module cover adapted to
close the entrance of a wafer transport module, said module cover
comprising at least one through hole on an upright peripheral wall
thereof respectively aimed at a respective latch hole on the wafer
transport module with which said module cover is used, and at least
one door latch transmission mechanism installed in said module
cover and respectively moved in and out of said at least one
through hole of said module cover and a respective latch hole on
the wafer transport module with which said module cover is used to
lock/unlock said module cover, wherein said at least one door latch
transmission mechanism each comprises: a driving wheel, said
driving wheel comprising a protruded center mount adapted to
receive handle means at the wafer transport module with which said
module cover is used, for enabling said driving wheel to be rotated
through which said handle means, and at least one smoothly arched
eccentric guide slot; a door latch, said door latch comprising two
latch arms connected in parallel, said latch arms each having a
front end and a rear end, the rear ends of said latch arms being
fixedly connected in parallel, and a coupling rod disposed at the
connecting area between the rear ends of said latch arms and
coupled to one smoothly arched eccentric guide slot of said driving
wheel for enabling said door latch to be moved forwards and
backwards between the locking position and the unlocking position;
and two latch bolts respectively coupled to the front end of each
of said latch arms of said door latch and moved with said latch
bolt in and out of said at least one through hole of said module
cover and the corresponding latch holes on the wafer transport
module with which said module cover is used to lock/unlock said
module cover, said latch bolts each comprising a bottom lug
inserted into the front notch of said door latch and pivotally
connected to the front end of said door latch by a pivot, a top
coupling block pivotally connected to a part of the module cover by
a pivot, and a front retaining block adapted for moving in and out
of one of said at least one through hole of said module cover and
the corresponding latch hole on the wafer transport module with
which said module cover is used to lock/unlock said module cover.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a wafer transport module
and, more specifically, to a door latch transmission mechanism for
a module cover for wafer transport module, which can smoothly
accurately be moved between the locking position and the unlocking
position with less effort.
[0003] 2. Brief Description of the Prior Art
[0004] Before becoming an IC chip, a wafer must be processed
through a series of processing procedures including diffusion,
printing, etching, masking, reading, and etc. Transport means are
used in factory to deliver wafers from one working area to another.
These transport means (cassette, boat, POD, or FOUP) are mainly to
protect wafers against contamination of dust and external objects.
FIG. 1 illustrates a transport means for this purpose. This
transport means is constructed according to U.S. Pat. No.
5,915,562, issued to Nyseth et al., entitled "Transport Module With
Latching Door". The wafer transport module 1 comprises a module
body 10 and a module cover 20. The module body 10 is adapted to
carry wafers W, having an opening 11 at one side thereof and a
plurality of latch holes 13 disposed around the opening 11. The
module cover 20 comprises an outer cover panel 21, and at least one
door latch 27 respectively slidably disposed on the inside. The
outer cover panel 21 of the module cover 20 comprises at least one
lock cylinder hole 25 or rotary handle 253. An implement can be
inserted to rotate each lock cylinder hole 25 and rotated to move
the respective door latch 27 in and out of a corresponding
peripheral through hole 23 of the module cover 20. Alternatively,
the user can directly rotate the rotary handle 253 to move the
respective door latch 27 in and out of the corresponding peripheral
through hole 23 of the module cover 20. In order to let the module
cover 20 close the opening 11 of the module body 10 tightly to
protect storage wafers W against outside dust, the door latch 27
will be moved forwards (toward the corresponding latch hole 13) and
then outwards (toward the outer cover panel 21) when extending out
of the respective peripheral through hole 23, to engage the
corresponding latch hole 13. To achieve this function, the door
latch transmission mechanism of the aforesaid design comprises a
rotary wheel 29. The rotary wheel 29 comprises a protruded center
mount 293 aimed at one lock cylinder hole 25 on the outer cover
panel 21 for receiving an implement being inserted into the lock
cylinder hole 25 for enabling the rotary wheel 29 to be rotated by
the implement, at least one first eccentric guide slot 295 and at
least one second eccentric guide slot 296. The door latch 27
comprises a first latch 271 and a second latch 272. The first latch
271 has a front coupling rod 275 coupled to one first eccentric
guide slot 296 of the rotary wheel 29. The second latch 272 has a
front coupling rod 276 coupled to one second eccentric guide slot
296. When rotating the rotary wheel 29, the first latch 271 and the
second latch 272 are respectively moved. The first latch 271 and
the second latch 272 are arranged in a stack. After extended out of
the respective peripheral through hole 23 (the X-axis direction),
the first latch 271 is forced by the second latch 272 to move in
Y-axis direction and to engage the corresponding latch hole 13.
This design of door latch transmission mechanism has numerous
drawbacks as outlined hereinafter.
[0005] 1. Because the second latch forces the first latch into
engagement with the corresponding latch hole, dust tends to be
produced to contaminate storage wafers during friction between the
first latch and the second latch.
[0006] 2. Because the second latch rubs against the inner surface
of the outer cover panel of the module cover during its movement,
dust may be produced to contaminate storage wafers due to friction
between the second latch and the inner surface of the outer cover
panel.
[0007] 3. During sliding movement of the door latch, much
resistance is produced against the movement of the first latch and
the second latch, and therefore much effort must be employed to
rotate the rotary wheel.
[0008] 4. Because the second latch is adapted to force the first
latch into engagement with the corresponding latch hole, the first
latch and the second latch must be will matched. Therefore, the
fabrication of the component parts of the door latch transmission
mechanism is complicated.
SUMMARY OF THE INVENTION
[0009] The invention has been accomplished under the circumstances
in view. It is therefore the main object of the present invention
to provide a module cover for a wafer transport module, which
eliminates the aforesaid drawbacks. It is another object of the
present invention to provide a module cover, which greatly reduces
the production of dust when operated to close/open the wafer
transport module. It is still another object of the present
invention to provide a module cover for a wafer transport module,
which can easily be opened and closed with less effort. It is still
another object of the present invention to provide a module cover
for a wafer transport module, which has a simple structure and, is
inexpensive to manufacture. To achieve these and other objects of
the present invention and according to one aspect of the present
invention, the module cover assembly comprises a module cover and
at least one door latch transmission mechanism adapted to
lock/unlock the module cover. The at least one door latch
transmission mechanism each comprises a door latch supported on a
roller at the module cover, a latch bolt pivotally coupled between
one end of the door latch and a part of the module cover, and a
driving wheel coupled to the module cover and rotated to move the
door latch forwards and backwards and to further turn the latch
bolt in and out of a through hole on the module cover and a
respective latch hole on the wafer transport module to lock/unlock
the module cover. According to another aspect of the present
invention, the driving wheel of each door latch transmission
mechanism comprises a center mount coupled to a handle means that
is disposed outside the module cover for operation by hand to
rotate the driving wheel, and a smoothly arched eccentric guide
slot; the door latch of each door latch transmission mechanism
comprises an upright coupling rod disposed at one end and coupled
to the smoothly arched eccentric guide slot of the respective
driving wheel for enabling the door latch to be moved forwards and
backwards by the respective driving wheel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a perspective view of a wafer transport module
according to the prior art showing the module cover removed from
the body of the wafer transport module.
[0011] FIG. 2 is an exploded view of the module cover for the wafer
transport module according to the prior art.
[0012] FIG. 3 is an exploded view of a door latch transmission
mechanism for a wafer transport module cover according to the
present invention.
[0013] FIG. 4A is a perspective view of the present invention
showing the latch bolt turned to the unlocking position.
[0014] FIG. 4B is similar to FIG. 4A but showing the latch bolt
turned to the locking position.
[0015] FIG. 5 is an applied view of the present invention, showing
the door latch transmission mechanism installed in a wafer
transport module cover.
[0016] FIG. 6 is a perspective view of an alternate form of the
present invention (the driving wheel excluded).
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] Referring to FIGS. 3 and 5, the door latch transmission
mechanism, referenced by 30, comprises a driving wheel 39, a door
latch 37, and a latch bolt 41. The driving wheel 39 comprises a
protruded center mount 393 to which handle means (not shown) is
connected for rotating the driving wheel 39 to move the door latch
37, and at least one, for example two smoothly arched eccentric
guide slots 395 symmetrically disposed at two sides relative to the
protruded center mount 393. The door latch 37 has a front notch 377
at one end, namely, the front end 373 thereof, two pivot holes 379
aligned at two sides of the front notch 377, and a coupling rod 375
at the other end, namely, the rear end thereof. The coupling rod
375 is inserted through one smoothly arched eccentric guide slot
395 of the driving wheel 39, enabling the door latch 37 to be moved
upon rotary motion of the driving wheel 39. The latch bolt 41
comprises a bottom lug 43, a top coupling block 45, and a front
retaining block 47. The lug 43 is inserted into the front notch 377
of the door latch 37 having a pivot hole 435 pivotally connected
between the pivot holes 379 of the door latch 37 by a pivot 437,
for enabling the latch bolt 41 to be moved with the door latch 37.
The top coupling block 45 has a pivot hole 455 pivotally connected
to a part of the wafer transport module cover, referenced by 31 by
a pivot 457. The front retaining block 47 of the retainer block 47
is moved with the door latch 37 in and out of a through hole 55 on
the vertical peripheral wall of the wafer transport module cover 31
(see FIG. 5) to lock/unlock the wafer transport module cover 31. A
cylindrical roller 53 is revolvably coupled to the driving wheel 39
by a pivot 537 to support the rear end of the door latch 37 on the
wafer transport module cover 31 and to prevent direct contact
between the door latch 37 and the wafer transport module cover 31,
for enabling the door latch 37 to be smoothly moved with the
driving wheel 39 in and out of the through hole 55. A cushion cap
51 is revolvably capped onto the coupling rod 375 and inserted with
the coupling rod 375 into one eccentric guide slot 395 of the
driving wheel 39 to buffer the pressure employed onto the coupling
rod 375 upon rotary motion of the driving wheel 39.
[0018] Referring to FIGS. 4A and 4B and FIG. 5 again, after
installation of the door latch transmission mechanism 30 in the
wafer transport module cover 31, the center mount 393 of the
driving wheel 39 and the top coupling block 45 of the latch bolt 41
are the fixed bearing points, i.e., the center of the center mount
393 as well as the center of the top coupling block 45 of the latch
bolt 41 are constantly maintained immovable. When rotating the
driving wheel 39 to shift the center mount 393 to the transverse
position as shown in FIG. 4A, the cushion cap 51 and the coupling
rod 375 of the door latch 37 are moved to a first position near the
center of the driving wheel 39, the door latch 37 is pulled
backwards, and the latch bolt 41 is turned about the pivot 457 in
counter-clockwise direction, and therefore the front retaining
block 47 is shifted to the unlocking position below the top
coupling block 45. On the contrary, when rotating the driving wheel
39 to shift the center mount 393 to the longitudinal position as
shown in FIG. 4B, the cushion cap 51 and the coupling rod 375 of
the door latch 37 are moved to a second position far from the
center of the driving wheel 39, the door latch 37 is pushed
forwards, and the latch bolt 41 is turned about the pivot 457 in
clockwise direction, and therefore the front retaining block 47 is
shifted to the locking position in front of the top coupling block
45. The front retaining block 47 of the latch bolt 41 has a
sector-like cross section. It is moved forwards in X-axis direction
and turned upwards in Y-axis direction when turning the driving
wheel 39 to push the door latch 37 forwards. Therefore, the front
retaining block 47 of the latch bolt 37 can be smoothly fitted into
the corresponding latch hole on the wafer transport module.
[0019] Referring to FIG. 5, two door latch transmission mechanisms
30 are installed in the wafer transport module cover 31. The pivot
457 of each door latch transmission mechanism 30 is connected
between two upright supports 57 in the wafer transport module cover
31, and the roller 53 of each door latch transmission mechanism 30
is maintained in contact with the inside wall of the wafer
transport module cover 31, and therefore the door latch 37 of each
door latch transmission mechanism 30 is kept away from the inside
wall of the wafer transport module cover 31. When moving the door
latch 37 between the locking position and the unlocking position,
the door latch 37 is not rubbed against the wafer transport module
cover 31. Therefore, the door latch 37 of each door latch
transmission mechanism 30 can be smoothly moved between the locking
position and the unlocking position with less effort without
producing much dust. According to the present invention, one
eccentric guide slot 395 is enough to move the door latch 37
between the locking position and the unlocking position.
[0020] Referring to FIG. 6, the latch, referenced by 67, comprises
a coupling rod 675 disposed at the rear end thereof and adapted for
coupling to one eccentric guide slot 395 of the driving wheel 39
(see also FIG. 3), and two latch arms 671 and 672 connected in
parallel. The latch arms 671 and 672 each have a free end pivotally
mounted with a respective latch bolt 61.
[0021] A prototype of door latch transmission mechanism has been
constructed with the features of FIGS. 3.about.6. The door latch
transmission mechanism functions smoothly to provide all of the
features discussed earlier.
[0022] Although particular embodiments of the invention have been
described in detail for purposes of illustration, various
modifications and enhancements may be made without departing from
the spirit and scope of the invention. Accordingly, the invention
is not to be limited except as by the appended claims.
* * * * *