Laminar flow air hood apparatus

Claim 1

A LAMINAR FLOW AIR HOOD APPARATUS COMPRISING THE COMBINATION OF GENERALLY UPRIGHT WALL MEANS SUBSTANTIALLY SURROUNDNG A SPACE, A GENRALLY HORIZONTALLY DISPOSED SUBMICRON AIR FILTER SUBSTANTIALLY FILLING A CROSS-SECTIONAL SPACE WITHIN CONFINES OF SAID WALL MEANS ADJACENT UPPER PORTIONS THEREOF, A TOP MEMBER SPACED ABOVE THE AIR FILTER AND JOINED WITH SAID WALL MEANS FORMING WITH THE LATTER AND AN UPPERMOST SURFACE OF THE AIR FILTER A PLENUM CHAMBER, A PLATFORM BELOW AND SPACED FROM THE AIR FILTER, SAID WALL MEANS INCLUDING PORTIONS FORMING AN AIR INLET PASSAGEWAY COMMUNICATING WITH THE PLENUM CHAMBER AND PORTIONS SPACED INWARDLY FROM THE EXTENDING GENERALLY ALONG OUTER PORTIONS AND FORMING WITH THE FILTER AND PLATFORM A WORK CHAMBER, AT LEAST PART OF THE WALL MEANS BELOW THE AIR FILTER AND ADJACENT THE PLATFORM BEING DISPLACEABLE TO PROVIDE AN OPENING FOR INGRESS AND EGRESS OF THE WORK CHAMBER, A THIRD CHAMBER OR COMPARTMENT EXTENDING BELOW SAID WORK CHAMBER AND PLATFORM, PARTITION MEANS FORMING A LOWER BOUNDARY OF THE THIRD CHAMBER EXTENDING GENERALLY BETWEEN THE WALL MEANS, A FOURTH CHAMBER BELOW SAID THIRD CHAMBER AND PARTITION, A LOWER END WALL FORMING A BOTTOM OF THE FOURTH CHAMBER, A SECOND AIR FILTER IN THE FOURTH CHAMBER, FIRST BLOWER MEANS IN THE FOURTH CHAMBER FOR DRAWING AIR THROUGH THE SECOND AIR FILTER AND DISCHARGING IT TO SAID INLET PASSAGEWAY AND SAID PLENUM CHAMBER TO FLOW THROUGH SAID SUB-MICRON AIR FILTER AND DOWNWARDLY AS A BODY OF AIR MOVING SUBSTANTIALLY PARALLEL TO SAID INWARDLY SPACED PORTIONS OF THE WALL MEANS AND WITH SAID BODY OF AIR TRAVERSING THE WORK CHAMBER BELOW THE SUB-MICRON FILTER IN AN ESSENTIALLY UNIFORM MANNER AND VELOCITY THROUGHOUT SUBSTANTIALLY ALL CROSS SECTIONS OF THE WORK CHAMBER, PASSAGEWAY MEANS PROVIDING COMMUNICATION BETWEEN THE WORK CHAMBER AND THE THIRD CHAMBER, SECOND BLOWE MEANS IN THE FOURTH CHAMBER FOR DRAWING AIR THROUGH THE PASSAGEWAY MEANS AND DISCHARGING IT EXTERNAL OF THE ASSEMBLY, MEANS FOR SELECTIVELY CONTROLLING THE QUANTITY OF AIR DISCHARGED BY THE SECOND BLOWER MEANS INDPENDENTLY OF THE QUANTITY OF AIR SUPPLIED BY THE FIRST BLOWER MEANS TO PROVIDE A BALANCED AIR FLOW CONDITION OR AN AIR INFLOW CONDITION VIA SAID OPENING OR AN AIR OUTFLOW CONDITION VIA SAID OPENING, AND AN OUTLET DRAIN FRON SAID THIRD CHAMBER FOR DISCHARGING FLUIDS FROM THE THIRD CHAMBER.