Hood

• US 3,880,062 A
• Filed: 11/08/1973
• Issued: 04/29/1975
• Est. Priority Date: 11/08/1973
• Status: Expired due to Term

• Current Assignee: Clifford Culpepper Jr, Robert M. Stuck
• Original Assignee: Clifford Culpepper Jr, Robert M. Stuck
• Inventors: Culpepper, Clifford Jr., Stuck, Robert M.
• Primary Examiner(s): Perlin, Meyer
• Assistant Examiner(s): Capossela, Ronald C.
• Application Number:
  US05/413,760
• Time in Patent Office: 537 Days
• Field of Search: 98/115K,115R 55/DIG.36
• US Class Current: 126/299.00E
• CPC Class Codes: F24C 15/2042 Devices for removing cooking fumes structurally associated with a cooking range e.g. downdraft F24C15/2007 takes precedence
• CPC Class Codes: Y10S 55/36 Kitchen hoods

Abstract

Airborne particulate matter is efficiently entrained into an air flow while the volume of air flow required is minimized by a hood which has walls defining an aerodynamically curving flow path with an entrance face having a first cross sectional flow area and a throat zone spaced downstream of the entrance face and having a cross-sectional flow area less than that of the entrance face. The throat zone is defined by the cooperation of an aerodynamically curving interior forward wall and lower and upper portions of a rear wall which are respectively directed forwardly toward the front wall and rearwardly away from a work surface underlying the interior forward wall.

Claims

1. Hood means for efficiently entraining airborne particulate matter, such as originates from a charbroiler during cooking, from above a work surface of known side-to-side and front-to-rear dimensions while minimizing the volume of air flow required, said hood means comprising:

side wall means defining right and left side walls rising from adjacent the right and left sides of the work surface and having front and rear portions, front wall means having a lower edge portion spaced upwardly from the work surface and generally overlying the front side thereof, said front wall means defining a smooth aerodynamically curving interior forward wall rising from said lower edge portion for assuring streamline flow of air therealong and within said hood means, said front portions of said side wall means, said lower edge portions of said front wall means and the work surface together defining an entrance face for said hood means through which air flow enters for entraining airborne particulate matter from above the work surface, and rear wall means defining a rear wall rising from adjacent the rear side of the worK surface and having a lower portion directed forwardly toward said front wall means and an upper portion directed rearwardly away from the work surface, said side wall means, front wall means, rear wall means and work surface together defining an at least substantially closed path for air flow, said front wall means and said rear wall means lower and upper portions together defining a throat zone within said air flow path, and the throat zone having a crosssectional flow area less than the cross-sectional flow area of the entrance face.

2. Hood means according to claim 1 wherein said wall means together define a flow path for air and entrained matter configured for constant acceleration of flow velocities between the entrance face and the throat zone.

3. Hood means according to claim 1 wherein said upper portion of said rear wall means defines with said front wall means and said sidewall means an expansion zone downstream of the throat zone and having a cross-sectional flow area greater than the cross-sectional flow area of the throat zone.

4. Hood means according to claim 1 wherein said lower and upper portions of said rear wall means diverge from a common horizontal edge spaced upwardly from the work surface and said lower edge portion of said front wall means.

5. Hood means according to claim 1 wherein said sidewall means have lower portions parallel one to the other and have upper portions converging toward one another and further wherein said upper and lower portions diverge from respective common horizontal edges which lie in a common horizontal plane spaced upwardly from the throat zone.

6. Hood means according to claim 1 wherein said front portions of said sidewall means and said lower edge portions of said front wall means define aerodynamically inwardly curving surfaces at the entrace face.

7. Hood means according to claim 1 wherein said interior forward wall defined by said front wall means has a generally horizontal entrance face portion overlying the extreme front edge of the work surface.

8. A ventilation system for efficiently entraining airborne particulate matter, such as originates from a charbroiler during cooking, from above a work surface of known side-to-side and front-to-rear dimensions while minimizing the volume of air flow required, the system comprising:

duct means for conducting a flow of air and entrained matter, fan means operatively communicating with said duct means for inducing flow of air and entrained matter therethrough, and hood means for overlying the work surface and having wall means for directing air flow relative thereto, said wall means including side wall means defining right and left side walls rising from adjacent the right and left sides of work surface and having front and rear portions, front wall means having a lower edge portion spaced upwardly from the work surface and generally overlying the front side thereof, said front wall means defining a smooth aerodynamically curving interior forward wall rising from said lower edge portion for assuring streamline flow of air therealong and within said hood means, said front portions of said side wall means, said lower edge portions of said front wall means and the work surface together defining an entrance face for said hood means through which air flow enters for entraining airborne particulate matter from above the work surface, and rear wall means defining a rear wall rising from adjacent the rear side of the work surface and having a lower portion directed forwardly toward said front wall means and an upper portion directed rearwardly away from the work surface, said side wall means, front wall means, rear wall means and work surface together defining an at least substantially closed path for air flow into said duct means, said front wall means said rear wall means lower and upper portions together defining a throat zone within said air flow path, and the throat zone having a cross-sectional flow area leSs than the cross-sectional flow area of the entrance face.