Devices for producing air screens

Claim 1

A DEVICE FOR PRODUCING AN AIR SCREEN ADJACENT THE DOORWAY OF A FREEZER ROOM WHICH COMPRISES: (A) AN AIR DISCHARGE CHAMBER ADJACENT ONE SIDE OF SAID DOORWAY, (B) SAID AIR DISCHARGE CHAMBER HAVING AN AIR DISCHARGE OPENING THEREIN, (C) AN AIR INLET CHAMBER ADJACENT THE OPPOSITE SIDE OF SAID DOORWAY, (D) SAID AIR INLET CHAMBER HAVING AN AIR INLET OPENING THEREIN, (E) A BLOWER THAT HAS THE INLET THEREOF CONNECTED TO SAID AIR INLET CHAMBER AND THAT HAS THE OUTLET THEREOF CONNECTED TO SAID AIR DISCHARGE CHAMBER, AND (F) AN AIR-DISCHARGING ASSEMBLY DISPOSED WITHIN SAID AIR DISCHARGE OPENING IN SAID AIR DISCHARGE CHAMBER TO GUIDE AIR ISSUING FROM SAID AIR DISCHARGE CHAMBER, (G) SAID AIR-DISCHARGING ASSEMBLY CAUSING AIR ISSUING FROM THE UPPER PART OF SAID AIR DISCHARGE OPENING TO INCLINE OUTWARDLY INTO THE AREA EXTERNAL OF SAID FREEZER ROOM, (H) SAID AIR-DISCHARGING ASSEMBLY CAUSING AIR ISSUING FROM THE LOWER PART OF SAID AIR DISCHARGE OPENING TO INCLINE INTO SAID FREEZER ROOM, (I) THE OUTWARDLY-INCLINED AIR ADJACENT THE UPPER PART OF SAID AIR DISCHARGE CHAMBER APPLYING A LONGITUDINALLY-DIRECTED OUTWARDLY-ACTING COMPONENT OF FORCE WHICH MATCHES AND WITHSTANDS THE COMPONENT OF FORCE APPLIED TO THE AIR SCREEN BY WARM AIR EXTERNAL OF SAID FREEZER ROOM ATTEMPTING TO ENTER SAID FREEZER ROOM ADJACENT THE UPPER PART OF SAID DOORWAY, (J) THE INWARDLY-INCLINED AIR ADJACENT THE LOWER PART OF THE AIR DISCHARGE OPENING APPLYING A LONGITUDINALLYDIRECTED, INWARDLY-ACTING COMPONENT OF FORCE WHICH MATCH AND WITHSTANDS THE COMPONENT OF FORCE APPLIED TO THE AIR SCREEN BY COLD AIR WITHIN SAID FREEZER ROOM ATTEMPTING TO ISSUE FROM SAID FREEZER ROOM, (K) PERFORATE MEMBERS MOUNTED IN SAID AIR INLET CHAMBER ADJACENT SAID AIR INLET OPENING, (L) SAID PERFORATE MEMBERS SUBTENDING AN OBTUSE ANGLE HAVING THE APEX THEREOF EXTENDING INTO SAID AIR INLET CHAMBER.