Roof ventilator

• US 3,101,662 A
• Filed: 09/03/1959
• Issued: 08/27/1963
• Est. Priority Date: 09/03/1959
• Status: Expired due to Term

• Current Assignee: Lawrence L. Alldritt
• Original Assignee: Lawrence L. Alldritt
• Inventors: Alldritt, Lawrence L.
• Application Number:
  US03/837,906
• Time in Patent Office: 1,454 Days
• US Class Current: 454/356
• CPC Class Codes: F24F 7/025 with forced air circulation by means of a built-in ventilator

Claims

1. IN A POWER DRIVEN ROOF VENTILATOR INCLUDING A ROUND CASING OPEN AT ITS TOP AND BOTTOM AND ADAPTED TO BE MOUNTED WITH ITS AXIS VERTICAL ON A ROOF OVER AN OPENING THEREIN AND TERMINATING UPWARDLY INA UPPER EDGE, A ROUNDED, DOWNWARDLY CONCAVELY CURVED HOOD FIXEDLY MOUNTED COAXIALLY ABOVE THE CASING AND EXTENDING LATERALLY OUTWARD BEYOND SAID UPPER EDGE OF THE CASING ON ALL SIDES OF THE CASING, A FAN WHEEL MOUNTED FOR ROTATION BENEATH THE HOOD COAXIALLY OF THE CASING AND INCLUDING A PLURALITY OF OUTWARDLY EXTENDING PROPELLER FAN BLADES, AND POWER MEANS FOR ROTATING THE FAN WHEEL ABOUT SAID AXIS;

THE IMPROVEMENT COMPRISING THE FAN BLADES HAVING AN UPPER PORTION HAVING AN UPWARDLY CONCAVE UPPER SURFACE MADE UP OF AN INFINITE NUMBER OF PARALLEL STRAIGHT LINES ONE OF WHICH PASSES THROUGH THE AXIS OF ROTATION OF THE FAN WHEEL AND IS INCLINED DOWNWARDLY OUTWARDLY AT AN ACUTE ANGLE TO THE HORIZONTAL AND IS DISPOSED ABOVE SAID UPPER EDGE, AT LEAST A PORTION OF THE BLADE EXTENDING BELOW SAID UPPER EDGE.