WaferTransportSolutionManual - 第18页
HEAVY PALLET RAILS MECHANICAL DETAIL 1.10 Wafer Transport Solutio n Chapter Issue 1 August 11 stopping repeatability of the pallet. The palle t continues to enter th e machine until detected by the board a t stop sensor …
HEAVY PALLET RAILS
MECHANICAL DETAIL
Chapter Issue 1 August 11 Wafer Transport Solution 1.9
Non-contact Board
Stop System
The board stop consists of a sensor fitted to the camera. As the pallet moves
into the print station the sensor detects its position.
To maintain a fast core cycle rate for print operations, the pallet (and wafer)
enter the machine very quickly (500mm/s).
As soon as the front edge of the pallet is detected, by the board at stop sensor,
the transport belt drive mechanism reduces speed, slowing the speed of the
pallet.
The camera and sensor assembly quickly relocates to the final alignment
position. This position is between 62mm and 72mm from the original camera
and sensor position. The pallet continues to advance at the reduced rate,
allowing the camera to be in position ahead of the pallet’s arrival, increasing the
Camera Board at Stop
Sensor
Pallet Enters
at 500mm/s
Pallet
View on Front of Pallet on Wafer Transport Rail (Front Rail Not Shown)
Rear Transport Rail Mechanism
Sensor Beam
Pallet
View on Front of Pallet Breaking Sensor Beam (Front Rail Not Shown)
Pallet Enters
Sensor Beam
HEAVY PALLET RAILS
MECHANICAL DETAIL
1.10 Wafer Transport Solution Chapter Issue 1 August 11
stopping repeatability of the pallet.
The pallet continues to enter the machine until detected by the board at stop
sensor for a second time. The pallet stops, it is now directly below the screen
image.
Pallet
View on Side of Camera Advancing to Final Position (Front Rail Not Shown)
62mm 72mmto
Pallet Advances at
Reduced Rate
Camera/Sensor
Quickly Advance
Pallet
View on Front of Pallet at Final Position (Front Rail Not Shown)
Half Pallet Length
HEAVY PALLET RAILS
MECHANICAL DETAIL
Chapter Issue 1 August 11 Wafer Transport Solution 1.11
Snugger Rail Snugger plates are fitted to the front and rear rails; the rear snugger provides
the pallet holding action.
With the pallet in position, the transport beam drops allowing the pallet overhang
edge to rest on the pallet support blocks. For extra support, and to prevent the
pallet from moving out of position, a pneumatic snugger mechanism on the rear
rail assembly, actuates, pushing the rear rail snugger plate toward the front rail.
Figure 1-5 Rear Rail Snugger Operation
Rear Rail Front Rail
Pneumatic Snugger Mechanism
(Rail removed for clarity)
Snugger
View on Left End of Rear Transport Rail
Snugger Off, Pallet Free
Snugger On, Securing Pallet
Snugger Plate
Top Plate
Pallet Overhang Edge
Pallet
Beam
Support Block