Claims
- 1. A curing oven having a housing enclosing an internal curing chamber comprising forward and rearward regions with bottom located forward and rearward access openings to and from said forward and rearward regions, a burner providing heated gases in a combustion region located above and isolated from said curing chamber by a heat shielding partition with deflectors therearound for deflecting and diffusing the heated gases from said burner downwardly into said curing chamber, said burner operating at a temperature sufficiently hot to provide a substantially non-poluting exhaust directly to atmosphere, fan means for blowing the heated gases downwardly into said curing chamber for curing of the material with the heated gases rising back upwardly and creating a negative pressure to draw a supply of fresh outside air into said curing oven through said bottom located access openings, a plurality of trays for carrying the material through said curing chamber, said trays being supported in side by side first and second vertical stacks in said forward and rearward regions and including a tray moving system comprising a first scissor lift for lifting said trays individually onto a cam operated pivotal catch weighted to normally assume a first stack supporting position relieving load on and freeing said first scissor lift to lower and receive further trays to be lifted to said pivotal catch, means for transfering the trays from atop the first vertical stack in said forward region to atop the second vertical stack in said rearward region, a second scissor lift for lowering the trays individually in the second vertical stack onto a slide bar immediately beneath the lowermost tray to assume a second stack supporting position with said slide bar being operated by a pivotal linkage which is in turn controlled by a piston to slide said slide bar in and out of the second stack supporting position.
FIELD OF THE INVENTION
This is a continuation of application Ser. No. 796,970 filed Nov. 12, 1985, now abandoned.
The present invention relates to a curing oven, divided into a combustion chamber and a curing chamber, separated from one another. The curing gases produced in the combustion chamber are diffused downwardly into the curing chamber, where they cure material carried on trays moved vertically, in a first upward and a second downward direction, through the curing oven.
According to conventional practice, as typically found in tunnel and cross flow-type curing ovens, the oven construction comprises an elongated horizontally extending housing structure, having full size access doors for entering the oven to enable loading and unloading of material to be cured within the oven. These types of ovens are highly inefficient, and therefore extremely costly to operate. They occupy large amounts of floor space and allow the escape of much of the heat energy produced internally of the oven when the doors are opened, for loading and unloading purposes.
For the reasons given immediately above, as well as to prevent burning of the material due to the proximity of the burner relative to the material, it is generally not possible with a conventional curing oven, to maintain the burner operating at a high efficiency, high temperature. This problem is further heightened, due to the fact that the material must be physically loaded and unloaded from the oven, where it would be dangerous to the operator to maintain extremely high curing temperatures. Therefore, by operating the burner at a lower temperature, as required with conventional ovens, the curing time is obviously increased and the burner itself, by not being operated at high temperatures, is relatively inefficient and incapable of providing a pollutant-free exhaust.
The present invention provides a curing oven, designed for high efficiency operation with reduced floor space requirements in comparison to prior art structures. More particularly, the curing oven of the present invention consists of an a housing enclosing an internal curing chamber, comprising forward and rearward regions, bottom located forward and rearward access openings to and from the forward and rearward regions respectively, a plurality of trays for carrying material to be cured through the curing chamber, conveyor means for carrying the trays to and from the forward and rearward regions through the forward and rearward access openings without requiring opening of the curing oven, a tray moving system for lifting the trays upwardly through the forward region and for transferring the trays to and for lowering the trays downwardly through the rearward region, a burner providing heated gases in a combustion chamber located above and isolated from the curing chamber, and fan means for blowing the heated gases downwardly into the curing chamber through diffusing means for curing of the material. The heated gases then rise back upwardly and create a negative pressure to draw a supply of fresh outside air into the curing oven through the bottom located access openings.
The curing oven of the present invention, including its vertically operating curing chamber, requires substantially less floor space then a conventional, horizontally extended curing oven. Furthermore, the use of a tray moving system, as described above, eliminates the requirement of having to open and physically load and unload the oven, and allows the curing oven of the present invention to be maintained at high operating temperatures for efficient curing purposes. Additionally, the isolation of the curing chamber from the combustion chamber enables the burner to operate at an extremely high and highly efficient burning temperature, which in turn results in an essentially pollution-free exhaust blown directly down to the curing chamber and which can be safely exhausted directly to atmosphere.
US Referenced Citations (7)
Continuations (1)
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Number |
Date |
Country |
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796970 |
Nov 1985 |
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Patent Grant
4717339
