Patent Publication Number: US-9888789-B2

Title: Refrigerated sales cabinet

Description:
The present invention relates to a refrigerated sales cabinet. More particularly, the invention relates to a refrigerated sales cabinet comprising a drain conduit in order to dispose condensed water. 
     Refrigerated sales cabinets for presenting cooled and/or frozen goods to potential customers including standalone refrigerated sales cabinets, which comprise a complete refrigeration circuit and need only to be connected to an electric power supply in order to operate the refrigeration circuit, are known in the art. 
     The operation of the refrigeration circuit comprised in this kind of cabinets usually produces condensed water, in particular at the evaporator. Said condensed water needs to be disposed from the goods presentation and air circulation space in order to maintain an attractive goods presentation and in order to maintain the cooling capacity of the refrigeration circuit. 
     It is known in the art to collect the condensed water in a condensed water collecting container, which is arranged below the evaporator and comprises a drain conduit in order to drain the water which has been collected in the container. As warm air ascending through the drain conduit and flowing by the evaporator reduces the efficiency of the refrigeration circuit, the drain conduit usually is provided with a siphon which is filled with water in order to prevent warm air from ascending through the drain conduit. 
     Filling the siphon with water before starting the operation of the refrigerated sales cabinets and regularly checking the amount of water within the siphon are perceived as inconvenient by the personnel e.g. in the supermarkets, and these actions considerably increase the effort and the costs for the installation and the maintenance of the refrigerated sales cabinets. 
     It therefore would be beneficial to provide a refrigerated sales cabinet with reduced installation and maintenance effort and costs while continuing to provide a reliable removal of condensed water from the goods presentation and air circulation space. 
     A refrigerated sales cabinet according to a first exemplary embodiment of the invention comprises a goods presentation and air circulation space comprising a goods presentation space for supporting refrigerated goods to be sold and an air circulation space comprising an evaporator for cooling air flowing through the air circulation space. The refrigerated sales cabinet further comprises a drain conduit fluidly connecting a bottom part of the goods presentation and air circulation space with a position outside of the goods presentation and air circulation space. Said drain conduit is configured for draining condensed water forming within the goods presentation and air circulation space to a position outside of the goods presentation and air circulation space and comprises an at least partially permeable container arranged along the flow path of the drain conduit, wherein the container is filled with granulate material that is non-absorbent to water. The granulate material is piled up within the container so as to occupy the full diameter of the flow path such that air is hindered or even prevented from passing through the drain conduit from outside of the goods presentation and air circulation space into the goods presentation and air circulation space and such that water still can pass through the drain conduit from the goods presentation and air circulation space to the position outside of the goods presentation and air circulation space. 
     A refrigerated sales cabinet according to a second exemplary embodiment of the invention comprises a goods presentation and air circulation space comprising a goods presentation space for supporting refrigerated goods to be sold and an air circulation space comprising an evaporator for cooling air flowing through the air circulation space. The refrigerated sales cabinet further comprises a drain conduit fluidly connecting a bottom part of the goods presentation and air circulation space with a position outside of the goods presentation and air circulation space. Said drain conduit is configured for draining condensed water forming within the goods presentation and air circulation space to a position outside of the goods presentation and air circulation space. The end of the drain conduit at the position outside of the goods presentation and air circulation space is facing upwards forming an angle of more than 0° with respect to a vertical plane. A flap is provided at said end of the drain conduit. Said flap is moveable between a closed position, in which the flap rests on said end of the drain conduit and hinders or even prevents air passing through the drain conduit from outside of the goods presentation and air circulation space into the goods presentation and air circulation space, and an open position, in which the flap is raised from said end of the drain conduit allowing water to pass through the drain conduit from the goods presentation and air circulation space to the position outside of the goods presentation and air circulation space. 
     In the refrigerated sales cabinets according to exemplary embodiments of the invention no water has to be present in the drain conduit in order to hinder warm air from ascending through the drain conduit into the goods presentation and air circulation space. Instead, air is blocked by the granulate material or the movable flap, respectively, from flowing through the drain conduit. At the same time the granulate material or the movable flap respectively allow condensed water to pass through the drain conduit in order to be removed from the water collecting container. 
     In consequence the invention provides refrigerated sales cabinets which may be installed and operated more conveniently as it is not necessary to ensure the presence of water in the drain conduit. 
    
    
     
       In the following the invention will be described in more detail with reference to the enclosed figures. 
         FIG. 1  shows a schematic cross section of an example of an integrated refrigerated sales cabinet according to a first embodiment of the invention. 
         FIG. 2  shows a schematic cross section through a net-bag filled with a granulate material according to an embodiment of the invention. 
         FIG. 3  shows a schematic cross section through a cartridge filled with a granulate material according to an embodiment of the invention. 
         FIG. 4  shows a schematic cross section of an example of an integrated refrigerated sales cabinet according to a second embodiment of the invention. 
     
    
    
     The exemplary embodiment of a refrigerated sales cabinet  1  shown in  FIG. 1  in particular is a standalone cooling or freezing cabinet to be used in department and/or grocery stores or the like in order to present cooled and/or frozen goods to the customers. It is, however, self-evident to the skilled person that the invention may be implemented in any kind of refrigeration sales cabinets comprising a drain conduit in order to discharge condensed water. 
     The exemplary refrigerated sales cabinet  1  shown in  FIG. 1  has a goods presentation and air circulation space  2  comprising a refrigerateable goods storage and presentation space  2   a  and an air circulation space  2   b . The air circulation space  2   b  may be integral with the goods storage and presentation space  2   a . In an alternative embodiment the air circulation space  2   b  may be separated from the goods storage and presentation space  2   a  by means of a barrier. 
     The refrigerateable goods storage and presentation space  2   a  comprises a plurality of goods presentation racks  5  for receiving the goods to be cooled and presented. The refrigerated sales cabinet  1  comprises a front opening  28  allowing access to the goods presented within the goods storage and presentation space  2   a.    
     Means for generating a first stream  4  of cooled air for cooling the refrigerateable goods storage and presentation space  2   a  and any goods (not shown) comprised therein are provided by means of a first fan  7  and a cooled air channel  26  directing a first stream  4  of air from a lower portion of the goods storage and presentation space  2   a  by an evaporator  6 , which is arranged in the air circulation space  2   b  below the goods storage and presentation space  2   a , through an air outlet  25  provided at an upper portion of the goods storage and presentation space  2   a.    
     A compressor  14  and a second fan  8  are arranged in a lower bottom portion  18  of the refrigerated sales cabinet  1  which is arranged below the goods presentation and air circulation space  2 . The second fan  8  is provided for generating a second air stream  10  which is directed through a rear air duct  20  past a condenser  12  arranged at an upper portion of an upper rear wall  16  defining the goods storage and presentation space  2   a . The compressor  14 , the condenser  12 , the evaporator  6  and an expansion device (not shown) form a refrigerating circuit, as it is known in the art. 
     When the refrigerating circuit is operating, the evaporator  6  cools the first stream  4  of air, which is guided through the air circulation space  2   b  by the evaporator  6  via the cooled air channel  26  and the air outlet  25  into the goods storage and presentation space  2   a  in order to cool the goods provided on the goods presentation racks  5 . 
     A roller blind  30  or a similar curtain is arranged at the top of the front opening  28  of the goods storage and presentation space  2   a  allowing to close the front opening  28 , e.g. during the night, providing a separation between the goods storage and presentation space  2   a  and the outer region in order to hinder or even prevent an exchange of cold air flowing out of the goods storage and presentation space  2   a  with warm air from the environment of the refrigerated sales cabinet  1 . 
     During normal opening hours the roller blind  30  is usually open in order to allow an easy access to the goods presented on the racks  5 . Alternatively, the blind  30 , which may be transparent, may be opened only for accessing the goods. Instead of a blind  3  a sliding or swinging door may be provided, which may be transparent, as well. 
     When the refrigeration circuit is operating, humidity comprised in the first stream  4  of air flowing through the air circulation space  2   b  will condense within the air circulation space  2   b , in particular at the evaporator  6 . If the refrigerated sales cabinet  1  is operated at freezing temperatures, the condensed water may freeze forming a layer of ice on the evaporator  6 . In this case the evaporator  6  needs to be defrosted regularly in order to maintain or restore its cooling capacity. 
     In order to collect condensed water including melting water dropping from the evaporator  6 , a water collecting container  32  is arranged at the bottom of the air circulation space  2   b . The water collecting container  32  is provided with a drain conduit  36  in order to drain condensed water collected in the collecting container  32  to a reservoir  38 , which is arranged within the lower bottom portion  18  of the refrigerated sales cabinet  1 . The drain conduit  36  is arranged at a steep angle, e.g. in the range of 70° to 90°, with respect to the horizontal in order to allow the condensed water to flow through the drain conduit  36  driven by its own weight. 
     The reservoir  38  may be heated, e.g. by means of waste heat generated by the operation of the compressor  14 , in order to evaporate the water collected in the reservoir  38  to the second air stream  10  passing through a lower bottom portion  18  of the refrigerated sales cabinet  1 . 
     As a stream of warm air flowing into the air circulation space  2   b  would reduce the efficiency of the refrigeration circuit considerably, it is beneficial to avoid warm air from ascending through the drain conduit  36  from the lower bottom portion  18  of the refrigerated sales cabinet  1  into the water collecting container  32  and the air circulation space  2   b.    
     In the first embodiment shown in  FIG. 1  a portion of the drain conduit  36  is filled with a granulate material  34 , so as to occupy the full diameter of the drain conduit  36 . The granulate material  34  is configured to allow water to pass through the drain conduit  36  from the top to the bottom of the drain conduit  36 , but to block air from ascending through the drain conduit  36  into the air circulation space  2   b.    
     The granulate material  34  may comprise pellets  52  and/or gravel filled in a container  54 ,  56 , for example a net-bag  54  or a cartridge  56 , which is part of or inserted into the drain conduit  36 . A support  40  may be provided in the drain conduit  36  in order to respectively support the container  54 ,  56  within the drain conduit  36 . The support  40  may be formed as a grid or orifice reducing the diameter of the drain conduit  36  in order to prevent the container  54 ,  56  from dropping out of the drain conduit  36 . 
     The longest extension of each of the pellets  52  may be in the range between 2 mm and 5 mm. The pellets  52  in particular may have a longest extension of 3 mm. Pellets  52  having this extension have proven to provide a granulate material  34  which is well suited for the intended purpose. The pellets  52  may be balls having a constant diameter. 
     Alternatively or additionally the granulate material  34  may comprise gravel. Gravel provides a cheap granulate material  34 , which, is well suited for the intended purpose. 
     Alternatively or additionally the granulate material  34  may comprise a synthetic material and/or silicium. The granulate material  34  in particular may comprise at least one of glass, stone, gravel, plastics, polymer, silicium, or a metal material, particularly steel or aluminium respectively providing a cheap granulate material which is well suited for the intended purpose. 
       FIG. 2  shows a schematic cross section though a net-bag  54  filled with granulate material  34  comprising a plurality of pellets  52 . The net-bag  54  may be formed as a net and/or from a textile material in order to allow water to pass through the net-bag  54 . The net-bag  54  may be made of plastic material. A net-bag  54  made of plastic material is cheap and long durable. 
       FIG. 3  shows a schematic cross section through a cartridge  56  filled with granulate material  34  comprising a plurality of pellets  52 . The upper and lower walls  55  of the cartridge  56  comprise openings or a water permeable membrane in order to allow water to pass through the walls  55  into and out of the cartridge  56 . The cartridge  56  may be removeably attached to the drain conduit  34  forming a portion of said drain conduit  34 . A removable cartridge  56  allows to replace the granulate material  34  easily and conveniently, if necessary. The cartridge  56  may be made of a plastic or metal material or a mixture thereof. 
     For the simplicity of illustration the pellets  52  forming the granulate material  34  shown in  FIGS. 2 and 3  are arranged in an almost regular order. The skilled person, however, will understand that the elements of a granulate material  34  are in general arranged chaotically without any order. 
       FIG. 4  shows an example of an integrated refrigerated sales cabinet  3  according to a second exemplary embodiment of the invention. 
     The features of the refrigerated sales cabinet  3  according to the second embodiment shown in  FIG. 3  which are identical to the features of the refrigerated sales cabinet  1  according to the first embodiment shown in  FIG. 1  are denoted with the same reference signs and will not be discusses in detail again. 
     In the refrigerated sales cabinet  3  according to the second embodiment at least a portion of the drain conduit  42  comprises a first conduit  44  and a second conduit  46  which extend in a basically vertical direction parallel to each other. The lower ends of the first and second conduits  44 ,  46  are fluidly connected to each other by a bottom portion  45  of the drain conduit  42 , the bottom portion  45  being connected between the first conduit  44  and the second conduit  46  so that the first conduit  44 , the bottom portion  45  and the second conduit  46  form a basically U-shaped siphon. 
     An upper end of the first conduit  44  opposite to the bottom portion  45  is fluidly connected to the bottom of the collecting container  32  in order to receive condensed water which has been collected in the collecting container  32 . The upper end of the second conduit  46  is open in order to allow condensed water flowing out of the collecting container  32  to spill out of the upper end of the second conduit  46  into the reservoir  38 , which is arranged below the opening provided at the upper end of the second conduit  46 . 
     In order to hinder air from entering into the drain conduit  42  via the opening provided at the upper end of the second conduit  46 , a moveable flap  48  is arranged at an upper end of the second conduit  46 . The moveable flap  48  may be attached to the upper end of the second conduit  46  by means of a joint or hinge  50  allowing the flap  48  to pivot with respect to the second conduit  46 . 
     In case no water is spilling out of the drain conduit  42 , the moveable flap  48  is moved into a closed position, in which it rests in the upper end of the second conduit  46 , by its own weight. In said closed position the moveable flap  48  seals the opening provided at the upper end of the second conduit  46  and hinders or prevents air from flowing through the opening into the second conduit  46 . 
     In case a sufficient amount of condensed water is flowing from the collecting container  32  into the drain conduit  42 , the water will push up the flap  48  into an open position allowing the water to spill out of the drain conduit  42  into the reservoir  38 , which is arranged at the very bottom of the cabinet  1  below the opening of the second conduit  46 . From the reservoir  38  the water is evaporated into the second air stream  10 , as it has been described with reference to the first embodiment. 
     Condensed water which is collected in the bottom portion  45  of the drain conduit  42  similar to a traditional siphon will provide an additional sealing hindering air from ascending through the drain conduit  42  into the collecting container  32 . However, even if no water is present in the bottom portion  45  of the drain conduit  42 , the air will be blocked reliably by means of the movable flap  48  when it is positioned in its closed position, as it has been described before. 
     The movable flap  48  may be made of an elastic material. An elastic material allows the movable flap  48  to move without providing a joint or hinge  50 . A movable flap  48  made of an elastic material further is well suited for tightly sealing the opening of the drain conduit  42 . In an embodiment the movable flap  48  is made of a synthetic material. A synthetic material may provide a cheap and long durable movable flap  48 . 
     As a result, the refrigerated sales cabinets  1 ,  3  according to exemplary embodiments of the invention reliably hinder or even prevent air form ascending through the drain conduit  36 ,  42 , which is provided for discharging condensed water, without the need of providing a certain amount of water in the drain conduit  36 ,  42 . Thus, the refrigerated sales cabinets  1 ,  3  according to exemplary embodiments of the invention may be installed and operated more conveniently than refrigerated sales cabinets as they are known from the prior art, and less maintenance is needed. 
     The exemplary embodiments of a refrigerated sales cabinets  1 ,  3  shown in  FIGS. 1 and 3  are standalone refrigerated cabinets respectively comprising a complete refrigeration circuit, which need to be connected only to an electric power supply for operation. Alternatively, a refrigerated sales cabinet may comprise only at least one evaporator to be fluidly connected to an external refrigeration circuit installed in the building in which the refrigerated sales cabinet is placed. 
     In an embodiment the drain conduit has a straight, non-bent shape and the longitudinal axis of the drain conduit forms an angle of 70 to 90° with the horizontal. A straight drain conduit is easy to produce at low costs and arranging the conduit at such an angle allows condensed water to flow through the conduit driven by its own weight. 
     In an embodiment the container, which is filled with the granulate material, forms a segment of the drain conduit. This provides a convenient way of providing the container including the granulate material within the drain conduit. 
     In an embodiment the container being filled with the granulate material is a cartridge, which is positioned within the drain conduit. A cartridge filled with granulate material and being positioned within the drain conduit allows to conveniently arrange the granulate material within the drain conduit and to remove the granulate material from the drain conduit, if necessary. 
     In an embodiment the container has a lower permeable wall onto which the granulate material is piled up providing a suitable means for placing the granulate material within the drain conduit. The permeable wall allows water to flow through the container. 
     The permeable wall may comprise a water-permeable membrane or openings having a diameter which is smaller than the smallest diameter of the elements forming the granulate material in order to prevent the granulate material from leaving the container. 
     In an embodiment the container, which is filled with the granulate material, is formed as a net-bag positioned within the drain conduit. A net-bag provides a suitable container for placing the granulate material within the drain conduit, which may be produced a low costs. The openings in the net-bag may be smaller than diameter of the granulate material in order to prevent the granulate material from leaving the net-bag or the container. 
     The net-bag or cartridge may be made of at least one of a net material, a textile material, or plastics material, each of which provides a cheap and well suited material allowing water to pass through the net-bag but preventing the granulate material from leaving the net-bag. 
     In an embodiment the drain conduit comprises a support for supporting the net-bag or cartridge. A support supporting the net-bag or cartridge within the drain conduit avoids that the net-bag or cartridge drops or is flushed out of the drain conduit. 
     In an embodiment the support is formed as a grid or as an orifice. A grid and an orifice respectively provide an adequate support, which may be produced and installed easily at low costs. 
     In an embodiment the granulate material comprises a plurality of pellets. Pellets have proven to provide a well suited granulate material reliably blocking air from flowing through the drain conduit but allowing water to pass through the material. 
     In an embodiment the granulate material comprises elements having a rounded and/or smooth surface. Elements having a rounded and/or smooth surface provide a well suited air-tight but water permeable granulate material. 
     The elements forming the granulate material may be uniform in size providing a homogeneous granulate material. Alternatively the elements forming the granulate material may have varying sizes providing a inhomogeneous granulate material. 
     The longest extension of the elements may be in the range of 2 mm to 5 mm, in particular approximately 3 mm. Elements having this size have proven to provide a well-suited granulate material. 
     In an embodiment the pellets are formed as balls, which have proven to provide a well suited granulate material. 
     The granulate material may comprise at least one of glass, stone, gravel, plastics, polymer, silicium, or a metal material, particularly steel or aluminium, which all have proven to respectively provide a well suited granulate material. 
     In an embodiment the fill level of the granulate material within in the container is at least 20 mm in order to provide a reliable air-seal within the drain conduit. 
     In an embodiment the granulate material comprises a material which does not absorb water and/or which is water repellent. This avoids that the material absorbs the water forming a wet mass which completely seals the drain conduit and does not allow any water to pass through the drain conduit. 
     In an embodiment the movable flap is configured to be moved into its closed position by means of gravity, in particular by its own weight. This reliably ensures that the flap is in its closed position blocking the flow of air through the drain conduit if no water is flowing through the drain conduit. 
     In an embodiment the movable flap is configured to be moved into the open position by means of the pressure of condensed water flowing through the drain conduit. This ensures that condensed water may always flow out of the drain conduit and is not blocked by a closed flap. 
     In an embodiment the flap is attached to the drain conduit by means of a joint or hinge allowing the flap to pivot with respect to the drain conduit. A joint or hinge allows an easy movement of the flap, ensuring that the flap opens and closes properly. 
     In an embodiment the flap is made of an elastic material. An elastic material allows the flap to move without providing a joint or hinge. A flap made of an elastic material further is well suited for tightly sealing the opening of the drain conduit. 
     In an embodiment the flap is made of a synthetic material. A synthetic material provides a cheap and long durable flap. 
     In an embodiment at least a portion of the drain conduit is form as a U-shaped siphon comprising at least two conduits, the flap being arranged at an upper end of one of the drain&#39;s conduits. A U-shaped drain conduit allows an easy installation of a flap which is moved into a closed position closing the drain conduit by means of gravity. Water collected at the lowest portion of the U-shaped siphon provides an additional air-seal. 
     In an embodiment the position outside of the goods presentation and air circulation space to which the drain conduit drains the condensed water is a water reservoir positioned in a bottom part of the refrigerated sales cabinet below the goods presentation and air circulation space in order to avoid that the condensed water leaving the drain conduit distributes in the lower portion of the cabinet. 
     In an embodiment the refrigerated sales cabinet comprises means for evaporating the condensed water collected in the reservoir. Evaporating the water collected in the reservoir using e.g. the waste heat of the refrigeration circuit is a convenient way for disposing the water from the reservoir. 
     The skilled person will easily understand that the first and the second embodiments of the invention as respectively shown in  FIGS. 1 and 4  may be combined by providing the drain conduit with both, a granulate material and a flap, in order to provide an even more reliable blocking of air from flowing through the drain conduit. 
     While the invention has been described with reference to an exemplary embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention is not limited to the particular embodiment disclosed, but that the invention will include all embodiments falling within the scope of the appended claims. 
     REFERENCE NUMERALS 
       1  refrigerated sales cabinet (first embodiment) 
       2  goods presentation and air circulation space 
       2   a  goods storage and presentation space 
       2   b  air circulation space 
       3  refrigerated sales cabinet (second embodiment) 
       4  first air stream 
       5  goods presentation racks 
       6  evaporator 
       7  first fan 
       8  second fan 
       10  second air stream 
       12  condenser 
       14  compressor 
       16  rear wall 
       18  lower bottom portion of the cabinet 
       20  rear air duct 
       25  air outlet 
       26  cooled air channel 
       28  front opening 
       30  roller blind 
       32  water collecting container 
       34  granulate material 
       36  drain conduit (first embodiment) 
       38  reservoir 
       40  support 
       42  drain conduit (second embodiment) 
       44  first conduit 
       45  bottom portion of the drain conduit 
       46  second conduit 
       48  moveable flap 
       50  joint or hinge 
       52  pellets 
       54  net-bag 
       55  upper and lower permeable walls of the cartridge 
       56  cartridge