Abstract: An open top refrigerated display case having an ambient air defrost system and a method of operating such display case, at least one air conduit extends in a U-shaped formation along opposing side walls and a bottom wall of the refrigerated display case. Each of the air conduits has an opening at both ends with such openings being located at upper portions of the side walls and in alignment so as to direct air across the access opening for recirculation through the air conduit during a refrigeration cycle of operation. Arranged within the primary air conduit is a set of refrigeration coils and at least one reversible fan for circulating air through such air conduit. During a refrigeration cycle of operation, the fan circulates air through the air conduit in a first direction through the refrigeration coils. During a defrost cycle of operation, the fan circulates air through the air conduit in the opposite direction and draws in ambient air from outside of the display case.

Abstract: A door operating mechanism for use with refrigerated display cases in which provision is made for one or more circulated air bands and an air defrost means. The door operating mechanism functions to selectively create a gap between the barrier door and the associated access opening of the case to carry out defrosting and to also permit the gap to be closed by the application of outside force. A motion take-up means is provided within the door operating mechanism to permit closing of a door through the operation of a flexing means which is preferably a compression spring. Temporary closing of the door gap by customers and employees is operatively provided for by the door operating mechanism.

Abstract: An energy efficient refrigerated display cabinet having glass barrier doors and one or more guard air bands to protect the primary refrigerated air band. A single guard air band is circulated about the primary refrigerated air band in order to protect the same from contact with the inner walls of the cabinet or the ambient air upon opening of the barrier doors. The cabinet can be provided with an air defrost system in which ambient air is taken in through ports in the cabinet which are selectively closed by gates or through a gap between the barrier doors and the associated access opening. An ambient air band can also be provided for circulation across the outer surface of the barrier doors in order to slightly raise the heat transfer into the glass panes in order to aid reduction of moisture condensate formation on the glass panes.

Abstract: A refrigerated display case comprising an outer cabinet having a bottom portion which slopes downwardly to form a drain region for collecting fluid material by gravity flow and a product display space within and spaced from the outer cabinet; one or more circulation conduits having an outlet opening and inlet opening on opposite sides of the cabinet access opening are defined between the outer cabinet and the walls of the display space. The conduits are further defined by a first relatively fixed bottom panel member and a second removable panel member. One end of the second panel member is loosely supported on the first bottom panel member. Support means are provided for loosely supporting the second panel member on the bottom portion of the cabinet in spaced relation thereto. A removable bottom shelf defines the bottom of the display space and is loosely supported above and in spaced relation to the second panel member.

Abstract: A refrigerated display case having a display section within a cabinet and a movable door covering a front access opening to such display section. A refrigeration air conduit extends along the top, bottom and rear walls of the cabinet. The air conduit has an outlet opening and an inlet opening at opposing ends thereof with the openings being in alignment so that air leaving the outlet opening will be directed towards and received by the inlet opening thereby forming an air curtain across the front opening of the cabinet along the path inside the door. During a refrigeration cycle of operation of the display case, refrigerated air is circulated through the air conduit and a refrigeration mechanism arranged within the conduit so as to establish a refrigerated air band and a refrigerated air curtain across the front opening in the cabinet. During a defrost cycle of operation, the refrigeration mechanism is turned off and the door covering the front access opening is slightly opened.

Abstract: An open top refrigerated display case having an ambient air automatic defrost system and a method of operating such a case. A single air conduit extends in a U-shaped formation extends around the case and has openings at both ends in the location of the upper portions of the side walls. At least one reversible fan and a set of evaporator coils are arranged within the air conduit. During a refrigeration cycle the fan circulates air through the air conduit in a first direction towards the evaporator coils. When frost buildup within the display case has reached a certain level, the system is switched to a defrost cycle of operation. During the defrost cycle, the fan circulates the air in the opposite direction through the air conduit and draws in ambient air from outside of the display case for defrosting the evaporator coils.

Abstract: An improved refrigerated merchandiser cabinet for food products storage and displaying which is equipped with transparent barrier doors which are openable by a door operating mechanism which selectively creates a gap between the door and the covered access opening to permit flow-through of ambient air for use during the defrost cycle. The door operating mechanism also permits the gap to be closed by imposition of an outside force by provision of a motion take-up means. Normal product entry and customer usage is provided for. Operation of the refrigerated cabinet with either a single or multiple air bands during a refrigeration cycle is provided for. During the defrost cycle a number of ambient air flow patterns can be employed, including the use of an auxiliary air fan. Reversal of the air band flow pattern during a defrost cycle is provided for. The method of operating the improved refrigeration display cabinet is also included.

Abstract: An open front refrigerated display case having mechanisms for establishing an inner refrigerated air band encircling the display portion of the case and secondary air band also encircling the display portion and being positioned outside of the inner air band. An inner air conduit passes around the cabinet of the display case and has an outlet opening at one end of the access opening in the front of the cabinet and an inlet opening at the other end of the front access opening in the cabinet. A fan circulates air through this inner air conduit with the air leaving the outlet opening and being directed toward and received by the inlet opening of the conduit, thereby establishing an inner air band along with an inner air curtain across the access opening in the front of the cabinet. An evaporator coil arranged within the inner air conduit serves to refrigerate the air passing along the inner air band during a refrigeration cycle of operation.

Abstract: A refrigerated display case having a mechanism for impeding the formation of condensation around the frame of the opening of the display case or at the junction of a door and a case frame of the display case. In one preferred embodiment, the ballast used in connection with the lights on commercial refrigerators and freezers are secured to the base in a manner which allows the heat generated by the ballast to be used to raise the temperature of the case frame. In another preferred embodiment the return conduit of the refrigeration system is employed adjacent the case frame for transferring heat from the refrigerant in the conduit to raise the temperature of the case frame as well as to increase the efficiency of the refrigeration system. In both of these embodiments, electrical resistance wires are included to supplement the heating provided by the ballast and the refrigeration system to ensure that condensation is prevented from forming on a frame or other desired portions of the case.

Abstract: An improvement in a refrigerated display case in which an air flow restriction baffle is positioned adjacent to the discharge end of the air conduit containing the defrost ambient air band. The baffle increases the linear velocity of the air band and the air momentum sufficiently to cause the band to flow away from the access opening of the display case whereby continuous recirculation of the defrost air is avoided. The baffle can form a restricted air flow cross-sectional area which is about 50% to 90% of the cross-sectional area of the air flow conduit immediately proceeding the position of the baffle. A restricted air flow area of these amounts enable a linear velocity increase of about 10% to 100% based on the air band velocities normally used during defrost cycles.

Abstract: A well type open top refrigerated display case has a primary air conduit extending around the cabinet and main fans for circulating air through the primary conduit and across the open top of the cabinet in the form of an air curtain. A column extends upwardly from and above the well type region; defrost fans are located in a defrost conduit in the column. Defrost control means are provided for energizing the defrost fans at the start of a defrost cycle to draw ambient air from above the refrigerated display case into the upper portion of the defrost conduit at a higher pressure than the air pressure in the region of the open top; a portion of the higher pressure ambient air is directed out of the defrost conduit to collide with the air curtain flowing across the open top, the flow of the air curtain being thereby reversed and caused to flow over the top of and outside the display case.

Abstract: An open top refrigerated display case having an upper display portion for displaying refrigerated products and a lower storage portion for storing refrigerated products. A cooling mechanism cools both the display portion and storage portion. The cooling mechanism establishes a refrigerated air band which encircles the display portion. This refrigerated air band is established by circulating air through an air conduit which surrounds the display portion and is positioned above the storage portion of the display case. Mounted within the air conduit is a fan and a set of evaporation coils. Air is expelled from one end of the conduit at an outlet opening located near the top of the display case and such air is propelled across the opening in the display case towards the opposite end of the case where it is received by an inlet opening of the air conduit. In this manner, an air curtain is formed across the top of the display case.

Abstract: A refrigerated display cabinet having air outlet ports in the top wall thereof for expelling ambient defrost air to the outside of the cabinet so that the air will not reenter the product display space. A baffle plate provided for blocking the passage of ambient defrost air into the top portion of the refrigerated air conduit during the defrost cycle from which it could flow into the product display space. A protective ambient air band is established across the access opening during the defrost cycle during which the flow of ambient defrost air is prevented from entering the internal cabinet product display space. The gate covering the air outlet port is used to mechanically control the closure of the baffle plate blocking the flow of ambient defrost air into the internal product display space.

Abstract: A refrigerated display case having a display section within a cabinet and a movable door covering a front access opening to such display section. The door includes a frame member in which two glass members are mounted with an air space between the glass members. A refrigeration air conduit extends along the top, bottom and rear walls of the cabinet. The air conduit has an outlet opening and an inlet opening at opposing ends thereof with the openings being in alignment so that air leaving the outlet opening will be directed towards and received by the inlet opening thereby forming an air curtain across the front opening of the cabinet along the path inside the door. During a refrigeration cycle of operation of the display case, refrigerated air is circulated through the air conduit and a refrigeration mechanism arranged within the conduit so as to establish a refrigerated air band and a refrigerated air curtain across the front opening in the cabinet.

Abstract: The interior walls of a refrigerated space below a product support shelf in a refrigerated case are automatically washed and cleaned at intervals.

Abstract: An island refrigerated display case can be constructed so as to in effect constitute to back-to-back display cases that can be arranged as a separate aisle within a supermarket. Such an island refrigerated display case has two interior display spaces separated by a partition wall with each display space having its own access opening so as to enable refrigerated products to be removed from that portion of the case. Encircling each of the interior display spaces is an associated refrigeration air conduit. Each of the refrigeration air conduits has an inlet and outlet opening positioned so as to direct air across the corresponding access opening for the interior display space. Thus during the refrigeration cycle of operation, a refrigerated air curtain is formed between the corresponding outer wall and the center partition wall so as to extend across the associated access opening. The portions of the refrigeration air conduits that extend through the partition wall can be joined so as to form a single chamber.

Abstract: A refrigerated glass door merchandiser in which heat generated during a defrost cycle of operation is prevented from flowing into the refrigerated display section. The glass door merchandiser is formed by a cabinet having an access opening in one of its walls with a glass door covering such access opening. The glass door is movable for enabling access through the access opening to products within the display section of the merchandiser. An air conduit extends around the cabinet and has an outlet opening at one end of the access opening and an inlet opening at the other end of the access opening. The outlet and inlet openings are arranged in alignment so that air circulated through the conduit and leaving the outlet opening is directed towards and received by the inlet opening for establishing a continuous air band around the cabinet and across the access opening during a refrigeration cycle of operation.

Abstract: A refrigeration system employs mechanical subcooling to substantially increase the efficiency of operation and reduce power consumption. The refrigeration system includes a compressor for compressing a gaseous refrigerant, a condenser for condensing the gaseous refrigerant and subcooling the liquid refrigerant, a receiver for receiving the liquid and a plurality of display cases having evaporators for evaporating the liquid refrigerant.A supplemental subcooling system, including a subcooling evaporator associated with the receiver discharge further subcools the condensed refrigerant before it is passed to the display case evaporators. The compressed gaseous refrigerant is first condensed at a condensing temperature of approximately 10.degree. to 25.degree. F. above a preselected cooling temperature. The condensed liquid is then mechanically subcooled if necessary to the preselected cooling temperature which should be preferably approximately 50.degree. F.

Abstract: A refrigerated display case having at least two outlet air conduits with a unitary grid member covering the outlet openings of such conduits. The display case is formed by a cabinet having an interior display space for holding refrigerated products. A primary air conduit encircles the cabinet and has an outlet opening at one end adjacent to an access opening in the cabinet and an inlet opening at its other end adjacent to the access opening. The inlet and outlet openings of the primary air conduit are aligned so that air leaving the outlet opening is directed across the access opening of the cabinet and received by the inlet opening. A set of evaporator coils are arranged within the primary air conduit for refrigerating the air passing through such conduits. The air is circulated through the primary air conduit by a set of fans. A secondary air conduit extends along the cabinet and is positioned outside of the primary air conduit.

Abstract: A refrigeration system employing ambient air defrost and a method of operating such a system. The refrigeration system includes a cabinet having an opening in one of its walls, for enabling access to products in the interior of the cabinet. Extending along the walls of the cabinet are an inner, primary air conduit and an outer, secondary air conduit. The primary air conduit contains a plurality of fans for circulating the air along the conduit and a mechanism for refrigerating air passing through the conduit during a refrigeration cycle. The air circulated through the primary conduit forms a closed primary air band. A plurality of second fans are arranged within the secondary air conduit and during a refrigeration cycle circulate air through the conduit, thereby establishing a closed secondary air band during the refrigeration cycle. When the system is to be defrosted, the refrigeration mechanism is deactivated so that the air passing along the primary air conduit is not refrigerated.