Fluid sprinkling – spraying – and diffusing – With cleaning means – drip collecting – waste disposal or soil... – Nozzle cleaner – flusher or drainer
Patent
1982-09-30
1985-04-09
Nase, Jeffrey V.
Fluid sprinkling, spraying, and diffusing
With cleaning means, drip collecting, waste disposal or soil...
Nozzle cleaner, flusher or drainer
239124, 239305, B05B 1502
Patent
active
045096848
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention is directed to the field of apparatus for applying multiple component sprayable fluids to a substrate using a manual spraygun. More particularly, the invention is directed to that portion of the above-noted field which is concerned with applying sprayable coating compositions which must be mixed in metered amounts just prior to application so as to avoid coreaction between components such as a color component and a crosslinking component. More particularly still, the present invention is concerned with the provision of apparatus for effecting rapid color change of the color component of a multiple component sprayable coating composition being applied to the substrate through the spraygun, which apparatus is adapted for rapidly flushing the system prior to changing to the next desired color.
BACKGROUND ART
In recent years the automobile industry has engaged in intensive research to develop coatings which require reduced energy consumption and which may be applied at reduced volatile organic compound (VOC) emissions levels. Recently developed multiple component sprayable coatings, which crosslink or cure upon combination of the components as they are applied, appear to offer a potential for not only reducing oven temperatures, and hence energy consumption, without adverse effect to the quality of the finish or the time required for completing crosslinking of the coating, but also potential for reducing VOC emissions. These multiple component coating materials which crosslink on the substrate after application normally include a crosslinking "accelerator" which is capable of increasing the rate of crosslinking at any given temperature. By varying the quantity of accelerator present in a coating, the crosslinking rate may be varied. The presence of any accelerator induces a tendency to crosslink at low, ambient, temperature and necessitates the maintaining of the material in component form until immediately prior to application as a coating.
Various multiple component coatings are available and will be apparent to those skilled in the art. One general class of two component paint system is based on polyurethane chemistry. Compositions of this type require one component containing a hydroxy functional resin (usually the color component) and another component containing an isocyanate crosslinker. These two components must be combined just prior to application to the substrate because the components would react prematurely if combined earlier. As is the case with all multiple component paint systems where a crosslinking reaction occurs after combination of components, the materials must be combined in precise amounts and, therefore, must be pass through or into the spraygun in metered amounts where they are combined just prior to application to the substrate. In order to combine the components in the proper ratio, it is therefore necessary to include metering means such as metering pumps and flow sensors as part of the apparatus used to apply the coatings.
Since multiple component materials must be combined in precise ratios as discussed above, thus necessitating more complex metering equipment, color change and flushing necessary to do so are greatly complicated. This is a particularly significant problem when coating operations require frequent, rapid color changes, such as in the automobile industry where it is very common to change colors between units on the line. In order to change a color, substantial quantities of solvent must be expended in order to remove all vestiges of coating material, particularly crosslinked material, from the spray apparatus and to remove all vestiges of the color component from those portions of the apparatus through which the color component passes. In order to avoid the necessity of having separate feed apparatus for each selected color including separate metering means for each, it is necessary to provide a means of rapidly flushing a single apparatus which can be used for all colors. It is also highly desirable to accomplish this flus
REFERENCES:
patent: 3023968 (1962-03-01), Mitchell
patent: 3145930 (1964-08-01), Herklotz et al.
patent: 3155531 (1964-11-01), Juvinall
patent: 3219273 (1965-11-01), Killen
patent: 3330290 (1967-07-01), Porter
patent: 3403695 (1968-10-01), Hopkins
patent: 3450092 (1969-06-01), Kock
patent: 3458133 (1969-07-01), Wiggins
patent: 3477870 (1969-11-01), Boretti et al.
patent: 3672570 (1972-06-01), Scarbrough et al.
patent: 3674205 (1972-07-01), Kock
patent: 3716191 (1973-02-01), Knight
patent: 3857513 (1974-12-01), Wiggins
patent: 3924806 (1975-12-01), Schowiak
patent: 4005825 (1977-02-01), Schowiak
patent: 4085892 (1978-04-01), Dalton
Ford Motor Company
Forman Michael J.
May Roger L.
Nase Jeffrey V.
Zerschling Keith L.
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