US 2230800 A
Description (OCR text may contain errors)
A. HORMEL .METAL SHEET DRYING OVEN Feb. 4, 1941,.
Filed Feb. 4, 1959 l ATTORNEY plantea at. 4, 1941 2,230,800 g UNITEDl STATES PATENT oFFlcE 2,230,800 METAL SHEET DRYING OYEN August Hormel, Hoboken, N. J., 'assignor to National-Standard Company, a corporation of Michigan Application February 4, 1939, .Serial No. 254,591 1 Claim. (Cl. :i4-12) This invention relates to an apparatus for dryhas its lower stretch 1 movable below the bottom ing freshly coated, lacqueredl or varnlshed sheet or floor 3 of the chamber, and its upper stretch metal plates or the like, and the object of the in- 8 movable through the chamber in the direction vention is to provide means for eilciently drying of the arrows in Fig. 1.
the plates while the same are being moved on a The conveyor is provided with a plurality of 5 conveyor througha drying chamber or oven. spaced racks 9 between which plates I0 to be A further object of the invention is the prodried are stacked so that the plates are carried vision of novel means for either uniformly or se- .through the chamber by the conveyor in the lectively controlling the temperature of the heatmanner well understood in this art, the dried ed air within certain areas through the oven. plates finally emerging out of the open exit end 10 'Another object of the invention is the proil of the drying chamber and being suiiiciently vision of means for cooling the plates at the exit cool to permit their being lifted off the conveyor. endoi the oven and @or exhausting the heated The structure thus far described is well known in air thereat. the art. More particularly, the invention contemplates At the entrance end 5 of thechamber, a double l5 the provision of a lengthy chamber or oven Walled enclosure I2 is provided, the spaces I3 bethrough which the plates to be dried are carried tween the walls thereof 'forming passages through on a conveyor; the provision of heating and airwhich vapors or fumes emanating from the varcirculating means 'arranged in group formation nished or coated plates just entering the chamthroughout the length of the oven, and the pro- 'bei'. may be drawn upward into .the pipe le by 20 vision oi means by which control of the heat in nie'ans of the suction pump I5 and exhausted any of said groups may be had. The invention therefrom through the pipe I6, to atmosphere. also contemplates the provision of means at the The inner wall Il of the chamber i2 is formed exit end of the drying chamber by' which air may with a plurality of apertures it through which be exhausted and the plates cooled immediately. the VapOrS paSS t0 enter the-passages i3 aS indi- 25 prior to their emergence from the drying chamcated by the arrows in Fig. 3. ber, so that the dried and cooled platea may be As the plates are carried through the chamber lifted from the conveyor, on the upper stretch 3 of the` conveyor they are In the accompanying drawing, wherein an emcarried past groups of air-circulating units i9, bodiment of the invention is shown, Fig. l. is a 2U. 2l and 22, which circulate heated air through 30 side elevation of the improved structure; Fig. 2 the chamber and around the plates, the air thus is a sectional view on the line 2-2 oi Fig. l, circulated being heated by suitable heating looking in the direction of the arrows; Fig. 3 is a means. In the form shown each of the air-cirtransverse sectional view on the line @-3 oi Fig. culating groups comprises four ducts itjoined by 1, looking in the direction of the arrows; Fig.y 4: a manifold pipe 24, which is connected to a blow- 35 is a sectional View at the exit end of the drying er 25. The ducts 23 are widened or flared at their chamber, showing the position of the cooling lower open ends and extend downward from the fans; andV Fig. 5 Vis a sectional view on the line blower 25 along one of the sidewalls 2. The
5 5 of Fig. l, lookingin the direction oi the arblowers are mounted on the top/or roof i of the rows. chamber, and the lower open end of each of the 40 The drying chamber or ovenis in the form cfa ducts is located near the floor and is curved lengthy structure generally composed oi sheet forwardly as indicated at 2b in Fig. 2. Air emametal and provided with a top or roof t, side hating out of the open end 2l of each of the ducts walls 2, and a bottom or floor t, thestructure is blown in a direction toward the opposite side being supported in a suitably elevated position wall 2 of the chamber and against a heated, up- 45 upon supporting legs It, or in any other frame. wardly curved, deector plate 2e, located in iront The walls, top and bottom of the lchamber are of a plurality of gas burners 29 located adjacent lined with an insulation or otherwise suitably inthe wall of the chamber, opposite to' that at sulated. At one end, the chamber is open as inwhich the ducts 23 are located. The air blown dicated at 5, this end ci the chamber comprising out of the ducts and circulating in the direction 50 the entrance end, where the conveyor is loaded of the arrows as shown in Fig. 2, passes around with the freshly coated plates, the entrance opcnthe yplates l0 carried by the conveyor and acts to ing being provided with a Suitable hood or other dry the plates, the air so circulated being drawn lprotective device fi.. Mounted to move through upwardly by the suction pipe 39 oi the blower g5 the chamber isan endless chain conveyor, which and into the blower.' The burners are so dis- 55 posed that each burner is located substantially opposite` to one oi' the air ducts 23, and the disposition of the plate 28 is such as to protect the flames of the burnersi from the air blasts from the ducts. Y i 'Ihe arrangement for the thermostatic control for the burners in each'group is shown in Fig. 5.`
It will be there seen that a gas supply' pipe 3l projecting on the outside of the chamber or oven from each burner is provided with acontrol valve 32, the several valves being linked together by rod By means of a properly positioned, independently adjusted, thermostaticcontrol l! for each of the heatergroups and accompanying air-circulating groups I9, 2li, 2| and 22, it will be apparent that the air .temperature prevailing adjacent each group may -be readily automatically controlled. The air circulated .through the chamber will, of course, be heated by the burners 29 and by contact wi-th the burner plates or de- At 'the exit end of the' chamber a hood p31 is provided and several motor driven fans 38, di'- rected upwardly toward the hood, deliver air blasts past .theplates l0 on-the conveyor, tending .to cool the same s o that they may be conveniently handled -to enable them rto be lifted v' 'from the conveyer when they emerge from the y so ' closed position, the
exit end of the same. The air blast so directed pases out through exhaust passage 82, leading from the hood 31.
Adjacent the hood 3l is or valve top or roof I lof the drying chamber, said door being capable of being held i'n any desired open or completely closed position to either rmit the exit of an air blast from a fan 4| or e se conilne the -blast within the chamber. When .the blast is coniined, by maintaining the door or valve 4l in blast from fan 4I acts as a wall of air under pressure to prevent longitudinal movement out of the chamber of the heated air generated yin the chamber -by the other burners and blowers.A When the door 40 is open, fan Il provided a trap-door -40 normally closing an opening in the used in co-operatlon with fans $8, will aid in clearing the chamber of vapors and fumes by blowing the same out through the opening.
Brietly.- the operation of -the structure is as follows:
'I'he coated plates are placed on Ithe conveyor either manually or by mechanical means, at the entrance end yB of the drying chamber. As the l plates are carried by the conveyor through the enclosure I2, the fumes and vapors arising from the plates will be drawn through the apertures I8 in the inner wall Il and pass out through the exhaust pipe I4. The conveyor .thereafter successively carries the plates past the blower groups t9, 2l, 2| and 2-2 which, with their associated burners. direct a continuous flow ofheatedgair around the plates to dry the coating thereon. Each of the burner groups may be controlled thermQstatica-lly, as described. When the `plates approach the exit end of the drying chamber, cooling blasts of air are directed upwardly past them, so that when they emerge from the egress end Il of the drying chamber, they are sutil- -ciently cooled to permit of'their being manually lifted from the conveyor.
What I claim is:
An apparatusof the character described comprising', an elongated heating chamber having an entrance at one end and an exit opening at its other end, aconveyor movable through the chamber for carrying' plates therethrough, heating means comprising a plurality of burners arranged along one side wall only of the chamber near the bottom of the chamber, a blower mounted on top of the chamber on the outside 'of the same, a plurality of air ducts connected to said blower and entrant into the chamber and disposed along the side wall onlyof the chamber opposite to that where the burners are located,rdeilector plates arranged in front of the burners and in position to directly deflect air forced across the chamber and impinged -against them by the ducts located at the opposite/wall. of the chamber, the ducts being provided" with flared open' ends directed toward and facing the deilector plates to thereby direct the air across the chamber against said plates, the chamber having an exhaust outlet Iconnected tothe blower.