US 4,785,552 A · Convection stabilized radiant oven

Abstract

A housing open at both ends has opposed concaved radiant emitter walls which are disposed on opposite sides of a conveyor for defining a drying chamber through which the conveyor moves freshly coated objects. Heated air from a closure is fed to outer cavities in the housing and this air passes inwardly through nozzle ports in partition plates to impinge and heat the walls. A major portion of the air returns to be reheated in the closure. Fresh air is introduced, in heat exchanging relationship to the heated air, to ducts which discharge into the drying chamber. Overhead fans selectively circulate turbulent or laminar air in the drying chamber. Air is withdrawn from both the drying chamber and the outer cavities via over head exhaust ducts. A computer and sensors control the temperature of the emitter walls by controlling the heating of the heated air. The computer and a sensor in the drying chamber controls the temperature of the air in the drying chamber to the same or a lower temperature than the wall temperature. Methods of drying paint or other coatings are disclosed wherein the ambient temperature of the air is controlled as to velocity and temperature and the temperature of radiant walls is controlled.

Claims38

Dependent claims

A convection stabilized radiant oven comprising:

(a) a housing having an open interior;
(b) conveyor means for moving successive objects along a path of travel through said oven from its entrance end to its exit end;
(c) a pair of spaced opposed radiant emitter walls disposed within said interior of said housing and on opposite sides of said path of travel for defining a longitudinally extending drying chamber with an entrance end and an exit end, said walls directing infrared radiant energy from said radiant emitter walls inwardly toward said path of travel when said radiant emitter walls are heated;
(d) means for heating said radiant emitter walls to prescribed temperatures for causing said radiant emitter walls to emit sufficient radiant energy inwardly toward said path of travel to heat said objects as they pass along said path of travel;
and
(e) air control means for adjusting the temperature of the air within said drying chamber to a prescribed and controlled temperature and for moving sufficient air within said drying chamber past said objects as they are heated by said radiant energy for stabilizing the temperature to which said objects are heated by said radiant energy.

3 more elements

A convection stabilized radiant oven comprising:

(a) a housing having a top and a pair of spaced opposed sides;
(b) a pair of concaved opposed radiant emitter walls disposed within the interior of said housing, said emitter walls defining, there between, a drying chamber;
(c) a conveyor passing through said drying chamber;
(d) means connected to said conveyor for supporting objects to be passed by said conveyor through said drying chamber;
(e) a pair of nozzle plates disposed respectively between said emitter walls and said housing walls, said nozzle plates each dividing the space between its associated side wall and its associated emitter wall into inner and outer cavities, said plate being provided with holes therethrough so that air within said outer cavities can pass inwardly through said holes and impinge against the outer sides of said emitter walls;
(f) a pair of longitudinally extending ducts disposed within said outer chambers;
(g) transversely extending ducts protruding through said radiant walls and communicating respectively with said longitudinally extending ducts;
(h) means for introducing air into said longitudinally extending ducts for delivery through said transversely disposed ducts into said drying chamber;
(i) means for heating air and for introducing this heated air into said outer cavities;
(j) means for removing air from said inner cavities;
and
(k) means for removing air from said drying chamber.

9 more elements

Dependencies are inferred from the claim text.

Convection stabilized radiant oven

Life of this patent

Convection stabilized radiant oven

Life of this patent

Abstract

Claims38