| 摘要 |
1042215 Coating apparatus P FULFORD 12 May 1965 [22 May 1964] 21162/64 Headings B1R and RU Apparatus for painting an article comprises an enclosed booth 10, a grille platform 13 spaced a short distance above the floor of the booth, means for maintaining a flow of liquid over at least an area of the booth floor beneath the grille, means for introducing clean air into the top of the booth and for extracting air from below the grille during a painting operation, and means for filtering, heating and recirculating the air supplied to the booth during a drying operation. In the arrangement shown liquid is discharged from pipes 18 so as to flow over trays 17 supported beneath the grille 13 to troughs 22 from whence it is drawn and filtered and recirculated. During paint spraying 100% fresh air is drawn into a heater and fan unit and discharged downwards through an air filter in the top of the booth and is extracted from exhaust ducts 16 after passing through a liquid curtain from the trays 17 as indicated by arrows 24, past scrubbing baffles 22a so that it is cleaned and filtered, and is discharged to atmosphere. During drying of the paint the liquid flow from pipes 18 is stopped and the air discharged into the booth is extracted as indicated by arrows 30 through filter 9 to a recirculating duct 7 from whence it is drawn back into the fan and heater unit. During this operation the air intake from atmosphere is reduced to about 10% of the whole, the remainder being extracted from the booth. To prevent leakage of air from the booth through the recirculating duct 7 during the paint spraying period a by-pass duct feeds a small quantity of air from the heater and fan unit to the duct 7 during this period. Safety devices include a limit switch in the fan and heater unit to ensure that there is the necessary air-flow before the heater is switched on and means situated in the exhaust ducts such that should there be an exhaust failure the heater will cut-out. Further an independent electrical thermostat is located in the heater fan casing and the air inlet duct in the roof of the booth may be lightly constructed to provide explosion relief. |
