3D Systems sPro, User Manual

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SLS p r o c e s s 1 6 5 I R S & I P C
u s e r ’ s g u i d e t r a n s p o r t i n g p o w d e r – f r o m I R S t o
S L S s y s t e m
Tra n s p o r t i n g Po wd e r – f r o m I R S t o S L S Sys t e m
During a build, an SLS system requests powder
from the IRS whenever its feed hopper gets low
on powder. “Low” means the powder level in the
feed hopper is below the upper level sensor.
When the feed hopper is low, the upper level
sensor’s LED switches off.
When the IRS receives a powder request from an
SLS system, it sends powder immediately—
unless it’s currently sending powder to another
SLS system, or in a blend cycle.
The IRS sends powder one transporter-load at a
time. The SLS system continues to request
powder until its feed hopper is “full” again; i.e.,
until the upper level sensor switches on (sensor
LED switches on).
Each powder transfer from the IRS to the SLS
system follows this sequence:
1
Transfer Request: SLS system sends the IRS a
message requesting a transfer.
2
Transfer Acknowledge: When ready to
transfer, the IRS sends the SLS system an
acknowledge message. The SLS system then
sets its powder control valves to receive the
powder and sends a “Valves Complete”
message to the IRS.
3
Transfer: the IRS transfers one transporter
load of powder.
4
Transfer Completion: When the load of
powder has transferred, the IRS sends the SLS
system a “Transfer Complete” message.
5
Transfer Completion Acknowledge: When
the SLS system has reset its powder control
valves, it sends a “Valves Reset” message to
the IRS.
Each step has a maximum time associated with it.
If the maximum time is exceeded on any one
step, the sequence starts over.