Glass door merchandiser

Claim 1

A refrigerated display case having a display section therein comprising: a cabinet having top, bottom, rear and side walls and an opening at its front; at least one door covering said front opening, said door being movable for enabling access through said front opening to products within said display section of said display case; an air conduit extending along said top, bottom and rear walls and having an outlet opening and an inlet opening at opposing ends thereof, said outlet opening and said inlet opening being arranged in alignment so that air leaving said outlet opening will be directed towards and received by said inlet opening and form an air curtain across said front opening along a path inside of said door; an air band establishing means for establishing a flow of refrigerated air through said air conduit during a refrigeration cycle of operation, said air band establishing means including refrigeration means and means for creating a positive pressure air flow through said refrigeration means; and defrost means for defrosting said display case when said display case is operated in a defrost cycle of operation, said defrost means causing ambient air to pass through a substantial portion of said air conduit, including that portion of said air conduit located along said rear wall of said cabinet of said display case, said defrost means causing the ambient air to flow in a reverse direction with respect to the air flow during a refrigeration cycle of operation and passing such ambient air through said refrigeration means for defrosting said refrigeration means and said air conduit while substantially preventing any ambient air flow into said display section of said display case.

Claim 12

A method of operating a refrigerated display case having: a cabinet with top, bottom, rear and side walls, an interior display section, and an opening at its front for enabling access to products within said display section; at least one door covering the front opening and being movable for enabling access through the front opening, an air conduit extending along the top, bottom and rear walls and having an outlet opening and an inlet opening at opposing ends thereof, with the outlet opening and the inlet opening being arranged in alignment so that air leaving the outlet opening will be directed towards and received by the inlet opening; and an evaporator coil being arranged within the air conduit; the method comprising the steps of: selectively operating the display case in a refrigeration cycle of operation and a defrost cycle of operation; during a refrigeration cycle of operation, circulating air through the air conduit so that air is expelled from the outlet opening and received by the inlet opening so as to form an air curtain across the front opening in the cabinet along a path inside of the door, propelling the air through an evaporator coil and refrigerating such air by using the evaporator coil as the air is circulated through the air conduit; and during a defrost cycle of operation; causing unrefrigerated ambient air to pass through a substantial portion of the air conduit, including that portion located along the rear wall of the cabinet, causing such ambient air to flow through the air conduit in a direction opposite the direction of air flow during a refrigeration cycle of operation, and preventing such ambient air from entering the display section of the cabinet.

Claim 13

A method of operating a refrigerated display case having: a cabinet with top, bottom, rear and side walls, an interior display section, and an opening at its front for enabling access to products within said display section; at least one door covering the front opening and being movable for enabling access through the front opening, an air conduit extending along the top, bottom and rear walls and having an outlet opening and an inlet opening at opposing ends thereof, with the outlet opening and the inlet opening being arranged in alignment so that air leaving the outlet opening will be directed towards and received by the inlet opening; and an evaporator coil being arranged within the air conduit; the method comprising the steps of: selectively operating the display case in a refrigeration cycle of operation and a defrost cycle of operation; during a refrigeration cycle of operation, circulating air through the air conduit so that air is expelled from the outlet opening and received by the inlet opening so as to form an air curtain across the front opening in the cabinet along a path inside of the door, propelling the air through an evaporator coil and refrigerating such air by using the evaporator coil as the air is circulated through the air conduit; and during a defrost cycle of operation; causing unrefrigerated ambient air to pass through a substantial portion of the air conduit, including that portion located along the rear wall of the cabinet, causing such ambient air to flow through the air conduit in a direction opposite the direction of air flow during a refrigeration cycle of operation, and preventing such ambient air from entering the display section of the cabinet.