Atmospheric pressure plasma system
OwnerAnthony Herbert, Fergal O'Reilly +2inventors
InventorsAnthony Herbert, Fergal O'Reilly, Jules Braddell, Peter Dobbyn
Life of this patent
Estimating the term…
Abstract
An atmospheric pressure plasma system (1) sharing electrodes (4) defining a plasma region (5) mounted in an enclosure housing (2). The enclosure housing has an open to atmosphere entry port assembly (10) and exit port assembly (11) for the continuous transfer of work-pieces through the plasma region (5). The embodiment illustrated is for precursor process gases having a relative density less than that of the ambient air so that the precursor gases rise in the enclosure housing (2) expelling the heavier ambient and exhaust gases. Where the gases have a relative density greater than ambient the port assemblies (10 and 11) are sited above the plasma region (5).
Claims23
An atmospheric process plasma (APP) system (1) of the non-thermal equilibrium type comprising:
- electrodes (3) forming a plasma region mounted in a gas-tight enclosure housing (2) having an open to the atmosphere entry port assembly (10) and exit port assembly (11), a non-ambient air precursor process gas having a relative density greater or less than ambient air at the same pressure and temperature and means (20) for moving work-pieces between the electrodes (3) for the entrance port assembly (10) to the exit port assembly (11) characterised in that each assembly port (10, 11) comprises an elongate enclosed housing having a work-piece port opening (12, 13) connecting the housing to the outside of the enclosure housing (2) and a vertically spaced-apart work-piece enclosure opening (14, 15) connecting the housing to the enclosure housing (2) and wherein the work-piece enclosure opening (14, 15) is below the work-piece port opening (12, 13) and is sited in the enclosure housing (2) above the plasma region (5) for precursor process gas with a relative density greater than that of the ambient air and below the plasma region (5) and above the work-piece enclosure opening (14, 15) for a gas with a relative density less than that of ambient air.
An atmospheric process plasma (APP) system (1) as claimed In any preceding claim in which a gas analyser (30) is mounted in the exit port (11).
An atmospheric process plasma (APP) system (1) as claimed in any preceding claim in a gas analyser (30) is mounted adjacent the work-piece port opening (10).
An atmospheric process plasma (APP) system (1) as claimed in any preceding claim in which the precursor process gas is maintained at a positive pressure above ambient pressure outside the enclosure housing (2).
An atmospheric process plasma (APP) system (1) as claimed in any preceding claim in which means (25) are provided for continuously introducing precursor process gas into the enclosure housing (2).
An atmospheric process plasma (APP) system (1) as claimed in any preceding claim in which means (43) are provided for the collection and removal of gases adjacent the exterior of each port assembly (10, 11) where a work-piece enters or leaves the port assembly (10, 11).
An atmospheric process plasma (APP) system (1) as claimed in any preceding claim in which an exhaust gas vent is provided in the enclosure on the side of the enclosure opposite to the port assemblies (10, 11) for the collection of exhaust gases having a relative density to that of the process precursor gases whereby they are trapped in the enclosure housing (2).
An atmospheric process plasma (APP) system (1) as claimed in any preceding claim in which gas flow dampers (16) are mounted in each port assembly.
An atmospheric process plasma (APP) system (1) as claimed in any preceding claim in which the electrodes (3) are substantially planar electrodes.
Dependencies are inferred from the claim text.