Patent Application
20060130752
The invention relates to an apparatus for spray painting articles of manufacture. More particularly, it refers to a compact spray table for imparting a chrome-like mirror finish on plastic, wood, aluminum, iron, stone and glass.
U.S. Pat. No. 3,861,989 describes applying to a glass sheet a coating of an alkyd resin, an epoxy resin, solvents and pigments. The coated glass sheet is then heated to remove solvent and cure the resin to produce a crackle finish decorative coating on the glass. Such a finish is not mirror-like and has to be treated with silvering solution to obtain reflective surface. In U.S. Pat. No. 4,975,305 an alkyd resin is used as a primer layer in a process for coating plastic, wood or metal articles in a spray booth. The search continues for improved processes for imparting high gloss finishes to manufactured goods and for a suitable spray booth that protects workers and prevents release of toxic vapors into the atmosphere.
The present invention is directed to an improved spray booth and improved process for coating chrome-like mirror finishes on manufactured items of varying types. The booth has a bottom tray supporting four pressurized 3-5 gallon tanks. These tanks contain the chemicals needed for a metallization process. Between the pressure tanks are waste recovery tanks. Above the tanks is an upper frame structure containing three upright walls enclosing a grated surface and a vertically narrow front wall. Three spray guns, with downwardly depending air pressure and chemical delivery hoses, are suspended from the front wall. A single air blower gun is also suspended from the front wall. The side walls contain perforated holes which allow the passage of vapors during the metallization process. Impeller blades contained in a housing attached to an outer surface of the side walls act to draw the vapors out of the spray booth.
This invention can be best understood by those having ordinary skill in the art by reference to the following detailed description, when considered in conjunction with the accompanying drawings in which:
Throughout the following detailed description, the same reference numerals refer to the same elements in all figures.
Referring first to
The upper frame structure 20 has a vertical front wall 22 of narrow vertical diameter, two oppositely positioned extended vertical side walls 24 and 26 and back wall 28 of similar height that enclose a grated work surface 30. The grated work surface 30 has a step down front surface 32 which is below a top portion 34 of front wall 22.
The side walls 24 and 26 contain circular perforations 36 for passage of vapors created on the grate work surface 30. A pair of impeller fans 37 are hingedly mounted within housing 38 attached to wall 24. Likewise a pair of impeller fans 37 are hingedly mounted within housing 40 attached to wall 26 (See
When needed, the entire spray booth 10 is manually moved in or out of any spray location with little effort.
The bottom tray 12 supports three gallon or five gallon stainless steel pressure tanks 46 and 47 on the right side and three gallon or five gallon stainless steel pressure tanks 48 and 49 on the left side.
One high velocity dual headed spray gun 54 and two single headed spray guns 50, 52, together with one air blow gun 56 are mounted on hooks 58 attached to front wall 22. Spray gun 50 is connected by flex coil 60 to pressure tank 48 containing tin chloride. This provides a sensitizing coating on an article to be metallized. Air pressure from an external source through connector 68 is provided by an air compressor. Air pressure is provided to tank 48 by hose 44. Tank pressure is monitored by a gauge 61 and air pressure to guns 50 and 52 is monitored by gauge 62 mounted on the outer side of wall 26 (See FIGS. 2 and 3). Pressure regulation settings are made by turning knobs 63 and 64 below gauges 61 and 62, respectively. The coil 60 is colored green for easy identification. An outer coiled tube 66 contains air from the external air compressor connected to the system at connector 68 (See
A polypropylene drain basin 78 (see
Quick connect valve connectors 84 (see
The spray gun 50 used for the sensitizer and spray gun 52 used for the de-ionized water are made of high impact plastic with stainless steel needles and internal fluid passages. The spray guns are corrosion free and fully adjustable for maximum performance. The gun 54 used for the silver nitrate and sorbitol reducer applications respectively is a specialized high volume dual headed spray guns allowing for the precise control and mixture of the two water base solutions which combine and produce the desired mirror finish. The guns are fully adjustable for any size work piece which can include glass, stone, wood, metal or plastic.
The grating 30 is stainless steel and the catch basin 78 is polypropylene for easy clean up. The frame structure is a heavy duty metal and the side walls are reinforced with stiffening member 42. A filter 86 can be used with impeller fans 37 to pick up particulate matter and prevent distribution to the atmosphere.
The metallizing process starts with the sensitizing of the surface of the article to be metallized by spraying the sensitizer through gun 50. The article is then rinsed with de-ionized water through spray gun 52. Silver nitrate and reducer are then sprayed from gun 54 onto the article to produce the chrome-like finish. The article is then rinsed with de-ionized water from gun 52, and then blown dry using air gun 56.
Various equivalent elements can be substituted for the elements described above for the metallizing spray table to provide substantially the same function in substantially the same way to achieve substantially the same result.
