Air ventilation system

Claim 1

An air ventilation system for cooking equipment having an exhaust hood disposed thereover in a kitchen in a building having a heating-ventilating and air-conditioning means for temperature treating the air in the building, characterized in that: (a) the exhaust hood is provided with a collection chamber disposed upwardly from and over the cooking equipment; (b) an exhaust chamber is formed in said exhaust hood and communicates with said collection chamber through an opening therebetween; (c) filter means is operatively mounted in said opening between said collection chamber and said exhaust chamber; (d) an exhaust passage means is connected to said exhaust chamber and extends from the kitchen to the exterior of the building in which the exhaust hood is mounted; (e) an exhaust fan means is operatively mounted on the exterior end of said exhaust passage means for exhausting a predetermined volume of air from said collection chamber and through the filter means, to exhaust cooking vapors, odors, fumes, smoke and other pollutants from the collection chamber; (f) a first and second source of fresh air is provided; (g) a first fresh air passage means is connected to said first source of fresh air and an air intake chamber in said exhaust hood; (h) said air intake chamber communicates with said collection chamber through an opening in which is disposed a fresh air diffuser means for directing fresh air from the first fresh air passage means toward the filter means; (i) a temperature control unit is operatively mounted in said building and is connected by an air curtain passage means, including a vertical portion disposed adjacent and along the front of the exhaust hood, for directing a temperature controlled air curtain downwardly along the front side of the exhaust hood, to prevent cooking vapors, odors, fumes, smoke and other pollutants arising from the cooking equipment to flow into the building from the kitchen in which the cooking equipment is positioned; (j) a second fresh air passage means is operatively connected between said second source of fresh air and said temperature control unit for selectively supplying fresh air to said temperature control unit; (k) a temperature treated air passage means is provided for selectively supplying temperature treated air to the temperature control unit from a source of the same which is exterior to the kitchen in which the cooking equipment is positioned; and, (l) said second fresh air passage means and temperature treated air passage means each includes flow control means for selectively controlling the flow of any combination volume of fresh air and temperature treated air to the temperature control unit, for forming an air curtain of a predetermined temperature.