Abstract: A refrigerated display case with multiple air curtain structure is disclosed. The multiple air curtains are defined by at least two air circulating conduits. An innermost conduit is partially divided into two chambers, and an evaporator is disposed in each chamber for generating the refrigerated air. A damper device extends across the discharge opening of the two chambers for selectively controlling the opening and closing of the discharge opening, whereby either one of the evaporators may be defrosted by blocking the air flow through the chamber within which it is contained, while the refrigerated air circulation continues through the other chamber to maintain the temperature in the case.

Abstract: A refrigerated display cabinet includes an insulating cabinet body having an open lateral or upper side, a partition plate disposed in the cabinet body and defining therein a storage chamber and a cooled air passage having an outlet extending along one edge of the open side and an inlet extending along an opposite edge thereof, a refrigerating unit and an air blower disposed in the cooled air passage for forcibly circulating cooled air to form an air curtain across the open side and cool the storage chamber, a humidifier unit disposed in the body outside of the storage chamber for producing a mist, and outlet pipe means for delivering the mist produced by the humidifier unit for being mixed in the forcibly circulated cooled air, the outlet pipe means having an outlet port positioned in the storage chamber in the vicinity of the outlet of the cooled air passage.

Abstract: Method and apparatus for prolonging the preservation of cut flowers involves cooling the bottom portion of a flower pot, which contains water in which the stems of cut flowers stand, while also cooling a semi-enclosed flower space with cooling air introduced in such fashion that the blooms of the cut flowers are not subjected to significant draft of the cooling air.

Abstract: A cabinet for cooling goods, e.g., flowers having a cooling system and an open space for freely exhibiting goods such as cut-flowers, a large amount of air is cooled, so that much moisture is set free. The invention provides a solution for a simple evacuation of the moisture by providing absorption means absorbing said moisture.

Abstract: A refrigerated-goods display case has its cold-air circulating blowers located between fin sections of the refrigerating unit cooling heat exchanger or evaporator against the rear wall of the goods display compartment.

Abstract: A refrigerated display counter has an interspace between an insulated tub-shaped cabinet and an inner tank forming a display surface. A cold air distribution duct provides for cold air flow over the display surface. An opening is provided in the cold air distribution duct, below the display surface level and deflector means are mounted in proximity to the opening for deflecting part of the cold air flow into the interspace.

Abstract: In an apparatus for preparing flavored frozen comestibles, the improvement comprising means for directing a stream of cold air at the surroundings of the equipment in which the product is being prepared, said air being sufficiently cold to reduce the temperature of the surroundings to about 45.degree. F.

Abstract: The present invention is a method and apparatus for cooling a frozen comestible plasticizer apparatus with a heat exchanger pan over a freezer, protecting the freezer from extraneous matter filling in, while providing a cool circulatable environment to cool the auger and cup of the apparatus to help avoid bacterial growth and minimize the need for cleaning of the apparatus.

Abstract: An improved evaporator unit in which a cooling tube core is placed between guide panels which permit a portion of the refrigerated air band to by-pass the front air opening of the core and to thereafter be forced into the core along a substantial longitudinal length of one or more side air openings. The flow of an auxilliary portion of the air stream into the side air opening permits the diffusion of frost build-up within the cooling tube core. A heater is provided for use during a defrost cycle in order to add heat directly into the cooling tube core. The improved evaporator is designed for use with reverse flow air defrost refrigerated container apparatus. Use of the evaporator permits improved refrigeration and defrost cycle operation.

Abstract: An air temperature regulating or conditioning control apparatus for use in a space having one or more refrigerated display fixtures. The fixtures have an open refrigerated display zone separated from the conditioned room space by one or more planes (curtains) of refrigerated air substantially lower in temperature than the conditioned room space, which absorb energy from the room air adjacent these planes thereby causing it to be cooled. The apparatus comprises a housing having a return air chamber and a make-up air chamber isolated from the return air chamber. Each of these parallel chambers has an outlet connected to a mixing compartment for mixing the conditioned air received from both chambers. An air moving means is connected to the mixing compartment for displacing the mixed conditioned air through air flow convection ducts back into the space. Each of the chambers further has an air intake or inlet, a filter section and a cooling section.

Abstract: A refrigerated display case having an ambient air automatic defrost system and a method of operating such a case. The display case has an access opening in one wall for enabling products within the display section to be removed. The access opening can be either in the top of front wall of the display case. At least one air conduit extends in an approximately C-shaped formation around the display case. The air conduit has openings at both ends, with such openings being located on opposite sides of the access opening. Arranged within the air conduit is at least one reversible fan and a set of refrigeration coils. During a refrigeration cycle the fan circulates air through the air conduit in a first direction towards the refrigeration coils. When frost buildup within the display case has reached a certain level, the system is switched to a defrost cycle. During the defrost cycle, the fan circulates in the opposite direction through the air conduit and draws in ambient air from outside of the display case.

Abstract: An electric outlet assembly adapted for mounting in an opening in a wall to secure a current take-off means at various fixed positions relative to the opening. The take-off means is mounted in a cover member which is arranged to block the opening at all positions at which the current take-off means is secured. Positive or negative air pressure can be maintained within the wall. The wall can be an air conduit partition in a refrigerated display cabinet.

Abstract: A refrigeration system utilizing cooled spillover air from a refrigerated display case 10, the spillover air being recovered and removed from the ambient space through openings 9. The recovered spillover air is conducted through conduit 29 in heat exchange relation to a subcooler 33, lowering the temperature of refrigerant passing to the display case evaporator 19, the still cool spillover air then being used in a space air conditioning system 30.

Abstract: A wide island, open top refrigerated display case of the air defrost type has a vertical, hollow partition extending centrally and longitudinally of the case. The partition functions, during defrost cycles only, as an air passage through which the flow of defrost air is induced by operation of a defrost fan mounted in a hollow sill extending along the top of the partition. During refrigeration cycles, the fan is idle and there is no air flow within the partition, so that it forms a hollow dead air space operative to insulate from one another the product wells separated by the partition, a feature of particular importance when one well is refrigerated to a temperature different from the other. Various configurations are disclosed, in some of which the air is forced downwardly within the center flue or passage during defrost, while in others the air is drawn upwardly through the defrost passage.

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: A refregerated showcase of the type that cold air is circulated across its front opening and along its bottom wall, rear wall and top wall, in which a guide plate having a short vertical length is provided hanging from a middle portion, in the depthwise direction of the showcase, of an ejection port of the cold air along the top edge of the front opening, whereby a rectified flow of an air curtain can be elongated down to a suction port along the lower edge of the front opening to prevent air in an ambient atmosphere from invading the showcase.

Abstract: Cabinet, in which cut-off flowers are cooled by cooling the flower boxes in which the flowers are put.

Abstract: A refrigerated display case having an ambient air automatic defrost system and a method of operating such a case. The display case has an access opening in one wall for enabling products within the display section to be removed. The access opening can be either in the top of front wall of the display case. At least one air conduit extends in an approximately C-shaped formation around the display case. The air conduit has openings at both ends, with such openings being located on opposite sides of the access opening. Arranged within the air conduit is at least one reversible fan and a set of refrigeration coils. During a refrigeration cycle the fan circulates air through the air conduit in a first direction towards the refrigeration coils. When frost buildup within the display case has reached a certain level, the system is switched to a defrost cycle. During the defrost cycle, the fan circulates in the opposite direction through the air conduit and draws in ambient air from outside of the display case.

Abstract: A refrigerated display case having a defrost means which combines the supply of hot refrigerant gas to the refrigeration coils with the supply of ambient air in order to provide defrost action during a defrost cycle. The ambient air band is taken into and propelled out of the air conduit in a manner to prevent ambient air from being forced into the product display space in order to avoid thawing of the stored refrigerated products. The defrost air is ejected away from the access opening in order to allow a cold air layer to remain on top of stored products in an open top case. In front cases, a defrost air band is established across the access opening to form a protective air curtain in order to exclude the contacting of the stored products with high temperature and moist ambient air. The ambient air band is unidirectional during the entire defrost cycle.

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. Defrost fans are mounted in the case to draw ambient air from above the refrigerated display case into an upper portion of the primary conduit at a higher pressure than the air pressure in the region of the open top. Defrost control means are provided for energizing the defrost fans at the start of a defrost cycle to propel a portion of the higher pressure ambient air out of the primary conduit through an air opening to collide with an 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. A further portion of ambient air is drawn downwardly by the main fans to flow through the primary conduit and assist in defrosting the coils.

Abstract: A refrigerated display case of the wide island type having side-by-side, upwardly opening product display wells, uses its primary air circulating fans and a defrost fan to draw ambient air into the inlet and outlet of the air conduit of one product well, circulate it through the conduit of that well, transfer it to the air conduit of the second well, circulate it through the second conduit, and discharge it to atmosphere through the inlet and outlet of the second conduit. The case incorporates a solid center partition having an opening near the bottom of the case in which the defrost fan is mounted to transfer the air from one product well to the other. A splitter panel and sill at the upper end of the partition prevent the intake air from becoming mixed with the exhausted air. During a defrost cycle the air can be drawn into the first well and exhausted from the second well for the full duration of the cycle.

Abstract: A cover for refrigerated display cases formed from a plurality of flexible, transparent, PVC strips attached together in side by side relation to form panels which extend across the display case access opening to provide a barrier which substantially reduces the heat transfer between the store environment and the display case contents.

Abstract: A refrigerated display case having a display space and an access opening, reversible fans for circulating air through an inner air conduit and across the access opening between a first outlet and a first inlet in a refrigeration mode to establish a primary air band; a second set of fans for circulating air through a second air conduit and across the access opening adjacent to and outwardly of the inner primary air band between a second outlet and second inlet to establish a secondary air band; and defrost cycle control means for reversing the air flow direction of the primary air band during a defrost cycle while maintaining the air flow direction of the second air band continuously in the same direction during both refrigeration and defrost cycles.

Abstract: An open top refrigerated display case having mechanisms for establishing an inner refrigerated air band encircling the display portion of the case and an outer air band also encircling the display portion and being positioned outside of the inner air band. An inner air conduit passes around the side and bottom walls of the cabinet of the display case and has an outlet opening at one end of the opening in the top of the cabinet and an inlet opening at the other end of the top 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 opening in the top 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, of the type in which air flows through a duct and is circulated about a product display space, has a service opening at the rear of the case. Disclosed is an accordion-pleated, hollow wall structure which is both an air duct and a door. The structure in its closed position communicates at top and bottom with adjacent portions of the conduit through which air is circulated during refrigeration or, in some instances, during defrost cycles of the case. In its open position, the hollow structure defines a service opening at the rear of the case through which dairy product support carts can be rolled into or out of the case. The hollow structure is sectionally formed in a manner to define the service opening at any selected cart location.

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 showcase characterized in that curtains superposed on each other in a plurality of layers so that an air layer or layers may intervene therebetween, are equipped along a front surface of a path of a cold air flow for refrigerating goods within the showcase, across the front opening of the body of the refrigerated showcase. Spacers are provided on the curtains in order to maintain the curtains in spaced relationship.

Abstract: A damper system, for a reach-in refrigerated display case of the air-defrosted type utilizes a single gear-reduction, reversible motor to operate between open and closed positions a multiplicity of dampers, all of which must be operated simultaneously. A radial arm on the motor shaft has a pin-and-slot connection to one damper connected to a series of other dampers pivoted about a common axis for joint opening and closing thereof. Each of the connected dampers includes cam means acting upon tongues of a second series of dampers pivoted about a common axis parallel to the axis of the first damper series. When the dampers of the first series are actuated to open position, the cams individual to the dampers of that series act to cause corresponding dampers of the second series to open simultaneously therewith. In a similar fashion, all the dampers are closed simultaneously by reason of their interconnection and cam action.

Abstract: A curtain comprised of a plurality of individual separable strips is provided for use across the front or top of a display type refrigerator such as used in supermarkets or the like. A sufficient number of strips are attached along the upper edge of the cabinet opening to span the width of the opening, each strip being of a length sufficient to span the length of the opening. Each strip detachably connects to the cabinet and is also detachably connected to one another whereby one or more strips may be removed from the cabinet and attached piggy back fashion to one or several strips for loading and unloading the refrigerator.

Abstract: A refrigerated display case for displaying refrigerated products. The display case is formed in a cabinet that has an interior area for holding the refrigerated products. The cabinet has an access opening for enabling access to the refrigerated products. A first air conduit extends around the cabinet and has inlet and outlet air openings for directing air across the access opening in the cabinet. During a refrigeration cycle of operation, the air traveling through the first air conduit is refrigerated by a set of evaporator coils. A second air conduit extends partially around the cabinet along a path lying outwardly of the first air conduit. The second air conduit has an outlet opening positioned adjacent to the outlet opening of the first air conduit. During the refrigeration cycle, partially cooled air is emitted from the outlet opening of the second air conduit along a path across the access opening of the cabinet but lying outwardly of the air emitted from the outlet opening of the first air conduit.

Abstract: A refrigerator wherein, in order to prevent cold air within the refrigerator body from flowing out while the door is opened, and air curtain will be formed in the opening of the body when the door is opened but will be removed when the door is closed.

Abstract: A refrigerated display case, of the reach-in type having a door normally closing a customer access opening, utilizes ambient air for defrost purposes by channeling it through an inlet conduit at the bottom of the case. The air is introduced into the normal air circulation pattern that obtains during the refrigerating cycle of the case, at the intake sides of the otherwise conventional primary circulating fan and its adjacent evaporator coil. The arrangement avoids reversal of the normal air circulation pattern and maintains a small but noticeable air flow, during a defrost cycle, through the product display area and along the inside of the glass door surface. The inflow of ambient defrost air is directed into the case through a defrost air inlet conduit having at its outlet end a continuously open air supply port, which opens into the primary air duct to provide for said introduction of defrost air into the normal air pattern.

Abstract: A refrigerated display case incorporates oppositely disposed display areas and has a common plenum chamber in fluid communication with said display areas. Common refrigerating coil means and compressor means provide refrigerated air to said plenum chamber for distribution to the oppositely disposed display areas.

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 multiband refrigerated display case having: an outer cabinet, an inner cabinet having an open product display space therein, and a divider between the inner and outer cabinets for dividing the space between the cabinets into adjacent first and second conduits. The divider comprises a first relatively fixed bottom panel member and a second removable panel member. The first bottom panel member has a U-shaped region for loosely receiving one end portion of the second panel member. Support legs are located on the underside of the second panel member for supporting the second panel member on the bottom portion of the outer cabinet in spaced relation thereto. Inlet grill means are loosely supported on the second panel in a position to cover the first and second conduit inlets; and a removable bottom shelf defining the bottom of the inner cabinet and display space is loosely supported on the removable second panel.

Abstract: An improved refrigerated merchandiser cabinet for food products storage and displaying which is equipped with both transparent barrier doors and an air defrost system to improve the energy efficiency. The barrier doors are openable for product entry and customer usage as well as by an air defrost system which creates a gap between the barrier door and the covered access opening to permit flow-through of ambient air for use during the defrost cycle. 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 pattern 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 improvement in open front refrigerated cabinets for food product storage and displaying in which transparent barrier doors and an air defrost system are provided for improving the energy efficiency. Barrier doors and an air defrost system can be retrofitted onto an open front refrigerated display case in order to permit operation of the cabinet with lower energy consumption. The air defrost system selectively creates a gap between the barrier doors and the associated access opening in order to provide for through-flow of ambient air during a defrost cycle. Open front cabinets having either single or multiple circulated air bands can be improved with this invention. The method of retrofitting such cabinets and the method of operations thereof is also included.

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 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: 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 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 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: 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 along opposing side walls and the bottom wall of the display case. The air conduit has openings at both ends in the location of the upper portions of the side walls. Arranged within the air conduit is at least one reversible fan and a set of refrigeration coils. During a refrigeration cycle the fan circulates air through the air conduit in a first direction towards the refrigeration coils. When frost buildup within the display case has reached a certain level, the system is switched to a defrost cycle. 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. Since such ambient air is of a higher temperature than the normally refrigerated air, it serves to defrost the system.