Abstract:
The invention provides a container for cooling produce. The container includes a box-like housing and a common plenum wall, creating a supply air distribution plenum, a return air distribution plenum and a treatment zone therebetween. Within the treatment zone, produce can be placed. A plurality of openings are located within the common plenum wall allows air flow to pass between the plenums and the treatment zone, and thus cooling the produced located therein.

Description:
REFERENCE TO PENDING APPLICATIONS  
       [0001]     This application does not reference any pending application.  
       REFERENCE TO MICROFICHE APPENDIX  
       [0002]     This application is not referenced in any microfiche appendix.  
       FIELD OF THE INVENTION  
       [0003]     The present invention is generally directed toward a cold room; more specifically, the present invention is directed toward a cold room for cooling produce including fruits and vegetables through a forced air process.  
       BACKGROUND OF THE INVENTION  
       [0004]     The present state of forced air cooling to rapidly remove field heat from recently harvested produce is well known. Typical techniques utilizing force air cooling are disclosed in the publication “Commercial Cooling of Fruits and Vegetables” by Thompson et al, available through the University of California, Agriculture and Natural Resources Communication Services, Oakland, Calf. 94608, U.S. Pat. No. 4,123,917 issued to Curtis et al., and U.S. Pat. No. 4,532,774 issued to Burns.  
         [0005]     Generally, harvested produce is packed into containers or bins. The cooling procedure to remove field heat from the produce is performed by utilizing high capacity fans that pull refrigerated air through the produce. Forcing refrigerated air to come into contact with warm produce at high speeds results in the rapid convective cooling of the produce. The cooling of the produce in a uniform manner is objective. Uneven cooling of the produce can result in damaged produce or produce not cooled to a sufficient temperature.  
         [0006]     A process for forced air cooling is known as tunnel cooling within a cooling room. The process includes creating an air tunnel by placing two parallel rows of palletized boxes with a space between the rows. The top and ends of the pallets are covered with a tarp. The space between the rows of pallets, above the floor, and under the covering tarp forms a tunnel, otherwise known as a return air plenum.  
         [0007]     The typical prior art design for implementing this process includes a refrigeration unit provides high pressure, refrigerated air into the cooling room. The walls, floor, and ceiling of the cooling room form a supply air plenum directing the refrigerated air across the produce. A fan is used to create a pressure differential with low pressure in the return air plenum. The pressure differential causes refrigerated air to be pulled through the produce into the return plenum. The return air plenum removes the warmed air from the cooling room and passes the warmed air through to the refrigeration unit. The now-refrigerated air is recycled back into the cooling room, thus completing the air circulation cycle.  
         [0008]     A disadvantage with the prior art designs is that air velocity and pressure differential is not uniform throughout the return and supply plenums. The air velocity within the two plenums is highest near the fan. Additionally, the pressure differential between the plenums is also highest near the fan. The lack of uniform air velocity and pressure differential causes the produce to cool unevenly with produce nearest the fan cooling more rapidly than produce farthest from the fan.  
         [0009]     An additional disadvantage is that the lack of air velocity and pressure differential uniformity limits the number of pallets of produce that can be cooled in one room.  
         [0010]     Another disadvantage is that if a cooling system is to be utilized for a number of fruits and vegetables, the system design must be able to adjust air velocities and adjust pressure differentials between the plenums. Different types of fruits and vegetables require various air velocities for optimum cooling rates. Carton or box design, amount and type of box ventilation, and type of packing liners all impact the pressure differential necessary to move air through the produce.  
         [0011]     A further disadvantage is that many produce cooling needs are seasonal. Conventional fixed base forced air cooling rooms service such seasonal markets are idle during the off season.  
         [0012]     A number of inventions disclose methods designed to improve uniform air velocity and pressure differential within a forced air cooling room or to provide transportable cooling rooms.  
         [0013]     U.S. Pat. No. 5,566,608 Vejdani teaches that placement of the supply and return fans at the end of the cooling room creates a definite length limit to the room such that a single air handling unit can only accommodate a predetermined number of pallets of produce. Vejdani discloses an apparatus placing the air handler on top of the product.  
         [0014]     U.S. Pat. No. 4,377,935 Curtis discloses an apparatus that utilizes a sub-floor return air plenum. However, this disclosure is cumbersome to create and does not provide uniform air flow across the pallets of produce.  
         [0015]     U.S. Pat. No. 5,789,007 Bianco discloses an apparatus that utilizes multiple top mounted air handlers to provide axial air circulation but does not provide even longitudinal air circulation between the axial partitions.  
         [0016]     While the prior art illustrates efforts to cool produce through forced air cooling processes, the prior art does not adequately address the need for uniform management of air velocity and pressure differential along the longitudinal axis of forced air produce cooling supply or return air plenums. Thus, there is a need to provide a forced air produce cooling room that addresses the disadvantages of the prior art.  
       BRIEF SUMMARY OF THE INVENTION  
       [0017]     The present invention satisfies the need discussed above. The present invention is generally directed toward a cold room; more specifically, the present invention is directed toward a portable cooling room for cooling produce.  
         [0018]     One aspect of the present invention provides a container for cooling produce including a box like housing having a ceiling, two side walls, two end walls and a floor. A common plenum wall is located proximate to one of the side walls creating a plenum therebetween. A second plenum is created between a second common plenum wall and the other side wall. The area between the two plenum walls is defined as a treatment zone. The treatment zone is dimensioned such that it can accommodate a row of pallets therein. Each common plenum wall has a plurality of openings to allow the passage of conditioning air to pass therethrough.  
         [0019]     A ventilation system in placed in communication with the two plenums providing circulation, and temperature control, to the conditioning air. A typical ventilation system includes a refrigeration component and an air movement component, such as a fan assembly. The refrigeration component provides cooling air into one of the plenums. The fan assembly draws air out of the second plenum. Due to the openings in the common plenum walls, the conditioning air passes from the first plenum into the treatment zone and then into the second plenum, creating a flow of conditioning air across the treatment zone and any item contained therein. These items can include pallets of produce to be cooled, such as strawberries, melons and lettuce.  
         [0020]     Due to the openings located within the plenum walls, a uniform air flow can be created across the treatment zone. This uniform air flow allows for uniform cooling of items inside the treatment zone.  
         [0021]     An additional aspect of the present invention includes having a common plenum wall proximate to the ceiling and a common plenum wall proximate to the floor. The openings contained within the ceiling plenum wall are located proximate to the side wall. The openings contained within the floor plenum wall are located proximate the longitudinal centerline of the floor. The treatment zone is located between the two common plenum walls. This configuration is adapted for use with two rows of produce pallets. The air flow can travel from the ceiling plenum into the treatment zone, across the rows of pallets and out the floor plenum.  
         [0022]     Another aspect of the ventilation system includes a fan assembly moveable between the two plenums. This would allow for the circulation between the air flow to be reversed without having to remove items located within the treatment zone.  
         [0023]     To further control the air flow through the treatment zone, another aspect of the present invention includes a flow barrier secured to the ceiling of the housing. This flow barrier can be lowered, or extended, from the ceiling onto the top of the items in the treatment zone. This reduces the amount of space above the items and concentrates the air flow through the treatment zone. Additionally, this flow barrier could be used to allow both configuration, i.e. side plenums or ceiling/floor plenums to be operational.  
         [0024]     Further features of the present invention will be apparent to those skilled in the art upon reference to the accompanying drawings and upon reading the following description of the preferred embodi [0001] An other aspect of the present invention includes a method to cool fruits and vegetables including providing a cooling room and cooling the fruits and vegetables therein. The cooling room is configured as set out above. Cooling air is provided into one of the plenums. A ventilation system creates circulation of the cooling air, which passes from one plenum, via openings contained in the plenum wall, through the treatment zone and into the other plenum via, openings contained in the other plenum wall. The openings allow for a substantially uniform pressure and velocity state of the air flow across the longitudinal length of the plenums.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0025]      FIG. 1  is a top view of an embodiment  20  of the present invention illustrating air flow traveling in a counter clockwise direction.  
         [0026]      FIG. 2  is a top view of embodiment  20  of the present invention illustrating air flow traveling in a clockwise direction.  
         [0027]      FIG. 3  is a top view of an embodiment of an adjustable aperture element of the present invention.  
         [0028]      FIG. 4  is a top view of an embodiment of an air directing vane element of the present invention.  
         [0029]      FIG. 5  is a top view of an embodiment of an air deflector element of the present invention.  
         [0030]      FIG. 6  is a top view of an embodiment  100  of the present invention illustrating multiple fans in a series in combination with a single return air distribution plenum.  
         [0031]      FIG. 7  is a top view of an embodiment  120  of the present invention illustrating a return plenum having multiple sub-plenums in a parallel.  
         [0032]      FIG. 8  is a top view of an embodiment  200  of the present invention.  
         [0033]      FIG. 9  is a side view of embodiment  200  of the present invention illustrating the direction of air flow.  
         [0034]      FIG. 10  is an end view of embodiment  200  illustrating transportation capability.  
         [0035]      FIG. 11  is an end view of embodiment  200  illustrating the direction of air flow.  
         [0036]      FIG. 12  is an end view of embodiment  200  illustrating the embodiment in a vertically retracted mode.  
         [0037]      FIG. 13  is an end view of embodiment  200  illustrating the embodiment in a vertically telescoping mode.  
         [0038]      FIG. 14  is an end view of embodiment  200  illustrating the embodiment in a horizontally retracted mode.  
         [0039]      FIG. 15  is an end view of embodiment  200  illustrating the embodiment in a horizontally telescoping mode.  
         [0040]      FIG. 16  is an end view of embodiment  300  of the present invention illustrating an embodiment of a flow barrier  310  in a retracted mode.  
         [0041]      FIG. 17  is an end view of embodiment  300  of the present invention illustrating an embodiment of flow barrier  310  in an extended mode.  
         [0042]      FIG. 18  is a side view of embodiment  300  of the present invention.  
         [0043]      FIG. 19  is an end view of embodiment  300  of the present invention.  
         [0044]      FIG. 20  is an end view of embodiment  300  of the present invention.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0045]     Before explaining the present invention in detail, it is to be understood that the invention is not limited to the preferred embodiments contained herein. The invention is capable of other embodiments and of being practiced or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein are for the purpose of description and not of limitation.  
         [0046]      FIGS. 1-2  illustrate an embodiment  20  of the present invention, which comprises generally a housing  30  having a floor  32 , a ceiling  34 , two side walls  36 ,  38  and two end walls  40 ,  42 .  
         [0047]     Inside housing  30  is a common plenum end wall  43 , a first common plenum wall  44 and a second common plenum wall  46 . Common plenum end wall  43  is located proximate first end wall  40 , but does not contact either side walls  36  or  38 . First common plenum wall  44  is located proximate to the first side wall  36  and extends from the second end wall  42  to common plenum end wall  43 . A first plenum  50  is created between side wall  36  and common plenum wall  44 . Second common plenum wall  46  is located proximate to the second side wall  38  and extends from the second end wall  42  to common plenum end wall  43 . A second plenum  52  is created between side wall  38  and common plenum wall  46 . A treatment zone  54  is created between the two plenum walls  44 ,  46 . Produce can be placed within treatment zone  54  through an opening located in second end wall  42  not shown. Located within each common plenum walls  44 ,  46  are a plurality of openings  60 ,  62 . These openings allow for air to pass between the plenums  50  and  52  and the treatment zone  54 . The direction of the air flow is dependant upon the orientation of the ventilation system  70 .  
         [0048]     As an example of the operation of this embodiment  20 , as illustrated in  FIG. 1 , cooling air  80  is provided into the second plenum  52  from a cooling unit  72 . A fan assembly  74  is in communication with the first plenum  50 . This fan assembly  74  creates a pressure differential between the air pressure in the first plenum  50  and the treatment zone  54 . This pressure differential causes the cooling air to be drawn from the second plenum  52  into the treatment zone  54  via the openings  62  located within the second common plenum wall  46  and then into the first plenum  50  via the opening  60  located within the first common plenum wall  44 . Due to the movement of the cooling air  80 A-E passing through the treatment zone  54 , the produce located therein is cooled to a desired temperature.  
         [0049]     One of the disadvantages of the prior art is the air flow across produce is not uniform, causing uneven cooling of produce. The openings in the common plenum walls  44  and  46  provide for the cooling air  80  to pass through the treatment zone  54  in a uniform manner, causing an even cooling of the produce. The velocity of cooling air  80  is greatest at the inlet and outlet of the first and second plenums  50 ,  52 , and lowest at the distal end of those plenums, as illustrated by the length of arrows associated with reference numerals  80 A-E. However, due to the openings  60 ,  62  a uniform layer of cooling air  83  forms within the treatment zone  54  proximate to the first common plenum wall  44  and remains uniform as illustrated by reference numeral  85  as it moves across the treatment zone  54 . This example is illustrative of this embodiment. Those skilled in the art will recognize that other configurations are within the scope of this invention. One such additional configuration is illustrated in  FIG. 2  wherein the fan assembly  74  is in communication with the second plenum  52 . This configuration provides the same cooling effect, but in the opposite direction.  
         [0050]     An additional embodiment of fan assembly  74  comprises one or more ventilation fans in communication with a support apparatus capable of allowing one or more the ventilation fans to move between two or more plenums. This support apparatus can include a support shuttle to house one or more ventilation fans slidably mounted within support tracks. The shuttle can be moved along the support tracks between two plenum to create alternate circulation patterns within the same housing without removing or otherwise disturbing the items located within the treatment zone.  
         [0051]     One of the disadvantages of the prior art is the air flow across produce is not uniform, causing uneven cooling of produce. The openings in the common plenum walls  44  and  46  provide for the cooling air  80  to pass through the treatment zone  54  in a uniform manner, causing an even cooling of the produce.  
         [0052]     Opening  60  and  62  can vary in opening size from one opening to another. This allows for differing amounts of air to pass between the respective plenum  50  or  52  and treatment zone  54 . These varying opening size can be either non-adjustable or adjustable. Other embodiments of openings  60 ,  62  include additional structure to assist the flow of air to pass between one of the plenums  50 ,  52  and the treatment zone  54 . Examples of this additional structure is illustrated in  FIGS. 3-5 .  FIG. 3  illustrates a series of openings  60  having adjustable shields  64 . These shields can be opened or closed depending on the amount of air flow needed to pass through that opening.  FIG. 4  illustrates a series of openings  60  having air directing vanes  66  connected thereto. These vanes  66  assist in straightening the air flow passing through a common plenum wall.  FIG. 5  illustrates a series of openings  60  having air deflectors  68  connected thereto. These air deflectors  68  assist in redirecting the air traveling along one of the plenums  44 ,  46  and into the treatment zone  54 . These embodiments of additional structures are illustrative and not meant to be limiting. Those skilled in the art would recognize other suitable structures can be employed to aid in the movement of air flow between the plenums  44 ,  46  and treatment zone  54 .  
         [0053]     Treatment zone  54  can be of various dimensions. One dimension can be of a size to fit a standard sized pallet such that the pallet is in contact with both common plenum walls  44  and  46 , not shown.  FIGS. 1-2  illustrate another dimension that provided for space to be between a row of pallets  76  and common plenum walls  44  and  46 . This space creates additional plenums  82  and  84  for the air flow. These plenums  82  and  84  augment the ability of the air flow to pass through the treatment zone  54  in a uniform manner.  
         [0054]      FIG. 6  illustrates an additional embodiment  100  of the present invention. This embodiment  100  is configured as the embodiment illustrated in  FIGS. 1-2 , but has only a single common plenum wall  110  on the return side of treatment zone  112  creating a return plenum  114 . A supply plenum  116  is created between the side wall  122  and the row of pallets  124 . As in the previous embodiments, common plenum wall  110  has a plurality of openings  118 , with each opening  116  having the same characteristics as set out above. Supplemental fans  120  are shown within return plenum  114 . These fans  120  can be utilized to aid in drawing cooling air from the end of the supply plenum  116  distal from the cooling air inlet  124 .  FIG. 9  illustrates two supplement fans  120  being in use. This number is merely illustrative. Those skilled in the art can recognized that more or less, including no supplemental fans, can be utilized.  
         [0055]      FIG. 7  illustrates an additional embodiment  120  of the present invention. This embodiment  120  is configured as the embodiment illustrated in  FIGS. 1-2 , but has one or more dividers  138 ,  140  within one or both of the plenums  122 ,  124 , creating distinct sub-plenums  126 ,  128  and  130 . Each sub-plenum  126 ,  128  and  130  being distinct from the other sub-plenums and having distinct fan assemblies  132 ,  134  and  136  in communication therewith. The use of the dividers  138 ,  140  and fam assemblies  132 ,  134 , and  136  allows for more control over the circulation of the air flow.  
         [0056]     An additional embodiment  200  is shown  FIGS. 8-9  of the present invention is illustrated. The embodiment  200  comprises housing  202  as set out above, with the first common plenum wall  204  is located between the ceiling  206  and floor  208  proximate to the ceiling  206 . This creates a ceiling plenum  210  between the first common plenum wall  204  and the ceiling  206 . The second common plenum wall  212  is located between the ceiling  206  and floor  208  proximate to the floor  208 . This creates a floor plenum  214  between the second common plenum wall  212  and the floor  208 . The treatment zone  216  is created between the first common plenum wall  204  and the second common plenum wall  212 .  
         [0057]     The treatment zone  216  is dimensioned to accommodate a two rows of pallets  222 ,  224  while creating two side plenums  218 ,  220  between one of the row of pallets  222 ,  224  and the side walls  232 ,  234  A central plenum  226  is created between the two rows of pallets  222 ,  224 .  
         [0058]     Located within the first common plenum wall  204  are a plurality of openings  230  located proximate both side walls  232 ,  234 . Openings  236  are located within the second common plenum wall  212  proximate to the longitudinal center line.  
         [0059]     A ventilation system provides circulation to the air flow such that air is supplied to the ceiling plenum  210  and is removed from the housing  202  via the floor plenum  214 . The air flow passes from the ceiling plenum into the treatment zone  216  via the openings  230  located in the first common plenum wall  204 . This air travels along the two side walls respectively, via the two side plenums  218 ,  220 , creating a uniform curtain of air. This uniform curtain of air then passes through the treatment zone  216  and into the floor plenum  214  via the openings  236  located within the second common plenum wall  212 .  
         [0060]      FIGS. 10-11  illustrates an embodiment  200  having transportable capabilities. The housing  202  is part of a trailer apparatus  240 . This allows for embodiment  200  to be moved to a location convenient for utilization. This capability can reduce the cost of transporting produce, fruits, vegetable to a processing center for conditioning. While these figures illustrate embodiment  200  being configured to be transportable, those skilled in the art would recognize that the embodiments of the present invention could be transportable. As such, the use of embodiment  200  is merely illustrative and not meant to be limiting.  
         [0061]      FIGS. 12-15  illustrate embodiment  200  in a transportable mode having the ability to modify the size of the housing  202  to accommodate more capacity within the treatment zone  216 .  FIGS. 17-18  illustrate the side walls  232 ,  234  being above to expand to increase the vertical height of the treatment zone  216 .  FIGS. 19-20  illustrate the floor  208  and ceiling  206 , along with the respective plenum walls  204 ,  212 .  
         [0062]      FIGS. 16-18  illustrate an additional embodiment  300  of the present invention. This embodiment  300  comprises a housing  302  as set out above and further including a flow barrier  310  to further restrict the air flow through the treatment zone  312 . This embodiment of flow barrier  310  includes a flow barrier plate  314  retractably secured to the ceiling  316  of the housing  302 . The flow barrier plate  314  can be lowered, or extended, from the ceiling  316  onto the top of the items  320  in the treatment zone  312 . This reduces or expands the amount of space above the items  320  and concentrates the air flow through the treatment zone  312 . Flexible material  322  is secured to the interior side of the flow barrier plate  314 , i.e the “items” side of the flow barrier plate  314 . The flexible material  322  allows for the items, such as pallets to be in protected when in communication with flow barrier  310 . Those skilled in the art recognize the raising and lowering of the flow barrier  310  can be accomplished through manual or automatic means along with actual or remote means. Additionally, this flow barrier could be used to allow both configuration, i.e. side plenums or ceiling/floor plenums to be operational. ( FIGS. 19-20 )  
         [0063]     An other embodiment of the present invention comprises a method to cool fruits and vegetables including providing a cooling room and cooling the fruits and vegetables therein. The cooling room is configured as set out above. Cooling air is provided into one of the plenums. A ventilation system creates circulation of the cooling air, which passes from one plenum, via openings contained in the plenum wall, through the treatment zone and into the other plenum via, openings contained in the other plenum wall. The openings allow for a substantially uniform pressure and velocity state of the air flow across the longitudinal length of the plenum.  
         [0064]     While the invention has been described with a certain degree of particularity, it is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification, but is to be limited only by the scope of the attached claims or including the full range of equivalency to which each element thereof is entitled.