Combustion convection oven with variable exhaust damper
AssigneeMiddleby Marshall Inc.
InventorRobert Van Murray
Life of this patent
Estimating the term…
Abstract
A combustion convection oven has improved energy efficiency. The oven includes a moveable exhaust damper that selectively closes off the exhaust plenum so as to inhibit the escape of heated air from the oven's cooking cavity. The exhaust damper is open when the oven is in a heating mode with the burners on, but closed when the oven is in a heated mode where the burners are off. Thus, airflow through the oven is significantly reduced or eliminated when the burners are off. That damper, or another damper, may have a degree of openness that is controlled to be inverse to the speed of the oven's fan.
Claims15
A method of reducing energy consumption when operating a combustion heated convection oven, the method comprising:
- operating the oven in a heating mode where:
- one or more burners of the oven, disposed in a combustion chamber, are on;
- heated air from the combustion chamber is supplied to a cooking cavity;
- a fan forcibly circulates air in the cooking cavity;
- an exhaust plenum is operatively open such that air may flow through the combustion chamber, through the cooking cavity, and through the exhaust plenum to outside the oven;
- thereafter automatically operating the oven in a heated mode where:
- the one or more burners are off;
- the fan forcibly circulates air in the cooking cavity;
- the exhaust plenum is substantially operatively closed so that air does not flow out of the cooking cavity, through the exhaust plenum, and then out the oven.
A combustion convection oven comprising:
- a housing having an air intake:
- a combustion chamber disposed downstream of the air intake and having a plurality of burners;
- a cooking cavity disposed downstream of the combustion chamber;
- a fan operable to forcibly circulate air in the cooking cavity;
- an exhaust plenum disposed downstream of the cooking cavity and leading from the cooking cavity to outside the housing;
- a first variable damper associated with the exhaust plenum and operative to automatically move between an open first position and a closed second position;
- the first position allowing airflow through the exhaust plenum;
- the second position substantially preventing airflow through the exhaust plenum;
- wherein the oven is operative in a heated mode and a heating mode;
- wherein, in the heated mode, the burners are off, the fan circulates air in the cooking cavity, and the first damper is in the second position;
- wherein, in the heating mode, the burners are on, the fan circulates air in the cooking cavity, and the first damper is in the first position.
Dependencies are inferred from the claim text.