US1646010A - Method of and apparatus for applying and treating varnish - Google Patents

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18 1.927. Oct 4 G. R. cLovER y METHOD OF' AND APPARATUS FOR APPLYING AND TREATING VARNISH Filed July 18, 1923 INVENTOR ff" HlsA-rfoRNEY Patented Oct. 18, 1927.

UNITED STATES l 1,646,010 PATENT OFFICE.A

GEORGE RICHARD 'CLOVEBb OF DETROIT, MICHIGAN, ASSIGNOR '1.0V COOPER HEWI'IT ELECTRIC COMPANY, 0F HOBOKEN, NEW JERSEY, A CORPORATION OE NEW JERSEY.

METHOD 0F AND APPARATUS FOR vAPPLYING AND TREATING VARNISH.

Application led J'uly 18, 1923. Serial No. 652,256.

Myinvention relates to a method and apparatus for the handling Aof automobile bodies and the like during the varnishing thereof for the purpose of facilitating the drying of the varnish.

It is well known in the art that ultra-violet light, to a marked degree, influences the drying of varnishes and oils. kAnd the greater the intensity of the ultra-violet light the greater the catalytic iniiuence which it exerts in its drying effect. In sunlight fresh varnishes and oils are dried through the influence ofboth the heat and light from the sun, and of the light rays thereof the ultraviolet rays are the most efficient in point of time in their drying effect. Artificial heat is often used alone for the drying process but, above certain limits of temper ature, the speed of drying cannot be accelerated because at about certain temperatures for given varnishes changes other than mere drying are brought about in the varnish which greatly shorten the life of the dried varnish. This shortening of the life of the varnish under excessive heat may even amount, for all practical purposes, to a coinplete destruction of the varnish. But the intensity of the ultra-violet rays may be considerably increased with an accompanying increase in speed of drying without any harmful effects to the varnish or oil. The general means of producingand supplying ultra-violet rays of greater intensities than are available from sunlight is the fused f quartz tube mercury vapor arc lamp.

I have discovered that by combining the applicationof heat and of ultra-violet light either together, in sequence, or in combination speedier results can be obtained than from the use of intense ultra-violet lightV alone.

and Fig. 4 is a diagrammatic representation o f the tunnel chamber of Fig. 1 having an air moistener connected therewith and means for forcing air therethrough into the Aprovide methods o f subjecting varnished or oiled surfaces to the infiuence of heat and of high intensity ultra-violet light.

Itis also the object of my invention to p rovide means for subjecting varnished or oiled surfaces to the influence of heat and of intense ultra-violet light.

The accompanying drawing shows in plan and section a varnish house of an automobile factory in which varnish is applied to prepared automobile bodies and dried thereon. Herein is shown an embodiment of my invention for handling these bodies in a manner according to my discovery of a method for their treatment for the drying of the varnish.

'.lhe tunnel or pocket type oven, 4, comprises tivo parts, the heating part, 7, or zone A, and the light and heat treating part 8, or zoneB. In connection with the tunnel are the varnishing floor 5 and the varnish vehicle drying chamber 6 from which the varnished` articles are-passed to the varnish drying oven 4. In the oven is the conveyor 3 which carries the varnished articles through the oven and light treating chamber 4. This conveyor in some cases is made to extend through both the evaporation chamber 6 and the chamber 4.. In other cases it is made to extend through the varnish Hoor, the evaporation chamber, and the chamber 4. In such cases the length ofthe varnishing floor and evaporation chamber along the conveyor are made to suit the time required fgr the application of the varnish and the evaporation of the varnished vehicle, respectively, as well as the speed of the conveyor as determined by the dimenlsion of and conditions in the drying cham- In chamber 4 heat is supplied for the drying process from the electric resistance heaters 2 and 2. These heaters serve also as stabilizing resistances for the mercury vapor or arc lamps 1. In the rear end 7 (zone A) of the chamber 4 resistance 2 alone is situated, while in the forward end lits travel the time during which the varnished'articles are subjected to the influence the varnished objects.

of the heat and the ultra-violet can be controlled.

My device consists of a system of conveyors, fused quartz mercury vapor arc lamps, heaters, ovens, etc., for the treatment of varnished objects. These are arranged to convey the varnished objects from the varnishing floor through an oven or series of ovens where under the influence of heat and ultra-violet light they are dried. The articles are conveyed through a varnishing room Where the varnish is sprayed on horizontal surfaces and flowed on perpendicular surfaces, from the varnish room they are conveyed to and through an evaporating room where they are subjected to heat for the purpose of evaporating the varnish vehicle or solvent. Up to this point my process is the same as is ordinarly employed for this purpose. But after the evaporating step instead of being subjected to heat for long periods of time for the purpose of drying the varnish the varnished articles are in my process and apparatus subjected to the influence of heat and light rich in ultraviolet rays. In my apparatus heat is supplied from electric heaters and for this purpose I use the resistances necessary in the circuit of the mercury-arc lamps used as the source of the ultra-violet light. In the oven the heaters are arranged so that the varnished articles would be subjected to the drying effect of heat before being subjected to the ultra-violet light. Some of the heaters are arranged to supply heat at the point at which ultra-violet light is applied to By preheating the varnish before subjecting it to the influence of ultra-violet light it is set and so kept from running. By doing this the drying is well advanced before the varnish is subjected to the influence of heat and light together. The temperature in the light zone may be the same as or different from the varnish setting zone. The completion of the drying is then effected in a very short time. In fact I find that in this manner varnished articles can be dried in about one fourth, or less, of the time usually required in the use of heat alone. I also find that my arrangement of the lamp resistors as heaters results in a saving of considerable -energy and also of apparatus due to the multiplying of the uses of the resistors.

In another form of the apparatus of my invention va turntable is used to carry the varnished articles through the drying chamber (see Fig. 3). In this case the light and heat sources are arranged about the conveyor to properly subject the articles to the influence of both. For some purposes the use of the turntable conveyors results in considera-ble saving in space and time of handling as well as the utilization of practically all of the light from some of the lamps wit-hout the use of reflectors. As is now well known in the art, these ovens of the pocket or the tunnel type. in the cold seasons of the year operate efii ciently. In the warmer seasons it will be found desirable to use air conditioning devices for reproducing in the ovens the desired drying conditions.

It is lwell known, too, that ultra-violet light sources generate quantities of ozone and in some instances it may be found desirable to withdraw the ozone or to modify the effect of anlexcess thereof by the introduction of a very slight amount of moisture which will be determined to be less than that found in practice to interfere with the drying operation. This, of course, will be taken care of through the conditioning apparatus during any season of the year. Such an arrangement is illustrated in the diagram of Fig. 4 in which the tunnel of Fig. 1 vis shown diagrammatically as having an air lIonoistener discharging into the tunnel chamer.

I claim as my invention:

1. In a varnish drying oven having heat sources and ultra violet light sources, in combination, a tunnel chamber, a conveyor therein, and varnish drying means arranged in two sections one following the other, the first including a he'at source and the other including a heat source and a source of light rich in ultra violet rays.

2. In a varnish drying tunnel oven having a heat source and ultra-violet light source, in combination, an endless conveyor extending lengthwise of said tunnel oven, and varnish drying means arranged in two zones one following the other, the first including a heat source and the other including a heat source lanfll1 a source of light rich in ultra violet 3. In a varnish drying oven having a heat applying zone and a heat and ultra-violet light applying zone, in combination, in the heat applying zone electric resistance heaters, in the' heat and ultra-violet light applying zone ultra-violet lamps andv electric resistance heaters, and connections between raid resistance heaters and said lamps, whereby the heaters act both as heaters and as ballast resistances for the lamps.

4. In a Varnish drying oven having heat and ultra-violet light sources, in combination, a tunnel chamber, a conveyor therein 'for carrying varnished articles past the said heat and light sources, and two varnished drying units arranged one after the other in the coun-ie of the lvarnished articles in the oven, the first including a heat source and the other including both a heat source and a source of light rich in ultra-violet light.

5. In a varnish drying oven having heat and ultra-violet light sources, in combination, electric supply mains, electric resistance heaters, ultra-violet light sources in thel form of mercury arc lamps, and connections between said mains, heaters and lamps whereby said heaters act as ballasting resistances for said lamps.

6. In a varnish drying oven having both a varnishv vehicle evaporating Zone in which is a source of heat supply and a varnish drying zone, in combination, electric heaters for supplying heat to said zones, electrical sources of light rich in ultra-violet rays, and electrical connection betwe'en said heaters and said light sources whereby said heaters act both as heaters and ballasting resistances for said light sources.

7. The method of applying and drying varnish on automobile bodies and the like which comprises applyingv varnish coatings to said bodies passing the bodies through a` heated atmosphere to evaporate the Varnish vehicle and to set the varnish, and then subjecting said bodies to the influence ot light. rich in ultra-violet rays until the varnish is suiiiciently dried for use.

8. In apparatus using drying varnish and the like, and in which a varnish drying electric light source requiring a ballasting resistance is used, in conibination, an electrical resistance heater for supplying heat to the material being treated, and Ielectrical connections between Isaid source of light and said heater whereby said heater serves as a ballast for said light.

9. In apparatus adapted to use' heat and light for treating varnish and the like, a source of Varnish drying light comprising a Vapor arc lamp, an electrical resistance for supplying heat, and electricall connections between said 4resistance and said lamp whereby the resistance serves as a ballast for the lamp.

Signed at Hoboken in the county of Hudson and State of New Jersey this 16th day of July A. D. 1923.

GEORGE RICHARD CLOVER.

light and heat yfor

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