Open-front refrigerated display case

Claim 1

IN A REFRIGERATED DISPLAY CASE HAVING A DISPLAY SPACE THEREIN, SAID CASE HAVING AN INSULATED BASE, AN INSULATED REAR WALL, A TOP, A LOWER FRONT WALL HAVING THE UPPER EDGE THEREOF SPACED FROM SAID TOP AND COOPERATING WITH SAID TOP TO DEFINE A NORMALLY OPEN ACCESS OPENING IN THE FRONT OF SAID DISPLAY CASE, AND MEANS FOR REFRIGERATING AND CIRCULATING AIR WITHIN SAID DISPLAY SPACE, THE COMBINATION OF MEANS FOR OVERCOMING THE EFFECT OF ANY SPILLAGE OF REFRIGERATED AIR FROM SAID ACCESS OPENING INTO THE AREA IN FRONT OF SAID CASE, COMPRISING DUCT MEANS FOR NONREFRIGERATED AIR EXTENDING ADJACENT BUT ON THE EXTERIOR OF SAID REAR WALL AND BASE OF THE DISPLAY CASE, SAID DUCT MEANS HAVING AN INLET OPENING LOCATED ADJACENT THE TOP OF THE CASE AND AN OUTLET OPENING LOCATED IN FRONT OF THE CASE BENEATH THE UPPER EDGE OF SAID LOWER FRONT WALL OF THE CASE, MEANS FOR CIRCULATING AIR THROUGH SAID DUCT MEANS TO THE AREA IN FRONT OF SAID DISPLAY CASE, AND MEANS FOR HEATING THE AIR CIRCULATED THROUGH SAID DUCT MEANS.