Patent Publication Number: US-6990827-B2

Title: Ice making apparatus for marine vessels

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates generally to ice making apparatus for marine vessels, and more particularly to apparatus which is capable of delivering ice to locations on the marine vessel spaced from the ice making apparatus. 
   Devices of the type to which the present invention relates can encounter difficulties with regard to reliability of operation since the ice must be driven through elongated delivery conduits to its ultimate destination. An auger or extruder mechanically drives the ice through a freezing chamber to an outlet from which the ice must be forced into and through the delivery conduits. 
   Ice leaving the extruder or auger must usually undergo a change in direction before it can pass to the outlet and through the delivery conduits. This can cause a problem because the ice may tend to accumulate before reaching the ice outlet thereby jamming the device and requiring shut down of the apparatus. Since the auger must continuously drive ice particles through the outlet, accumulation of ice particles can make continued operation of the auger impossible. 
   Usually, ice leaving the upper end of the auger has imparted thereto a vertically or axially directed force. However, before the ice can pass through the discharge opening it must undergo a change of direction of 90° or more thereby causing the ice to accumulate and jam the evaporator unit. 
   Furthermore, the need to deliver ice to remote locations can cause problems depending upon the distance through which the ice must travel since the auger alone may be unable to impart sufficient driving force for the ice to reach its ultimate destination. 
   Accordingly, it is an object of the present invention to provide marine ice making apparatus involving an auger driven ice making assembly which can provide smoother operation and operate more reliably substantially reducing the tendency of the apparatus to jam. 
   A further object of the invention is to provide a split system wherein a refrigeration assembly for providing refrigeration fluid and an evaporator assembly which includes an auger rotating within a freezing chamber or the like may be installed separated from each other thereby allowing more flexibility in the installation of the apparatus whereby the evaporator unit may be placed closer to the ultimate destination of the ice units to reduce the distance between the evaporator unit and the ice delivery location. 
   An additional object of the invention is to provide means for fragmentizing the ice particles leaving the end of the auger in order to facilitate moving the ice units into and through the delivery conduits. 
   A still further object of the invention is to provide means in addition to the auger to impart an additional delivery force to the ice units directed more in line with the direction in which the ice units must travel as they exit the evaporator unit into the delivery conduits. 
   SUMMARY OF THE INVENTION 
   Briefly, the present invention may be described as a marine ice making assembly including a refrigeration unit and an evaporator unit which may be mounted apart in order to provide flexibility in the placement of the apparatus thereby to reduce the distance through which ice must travel to reach its ultimate destination on the marine craft. The evaporator unit includes a freezing chamber surrounded by refrigeration coils which receive refrigeration fluid from the refrigeration unit in order to freeze water introduced into the freezing chamber. The ice units thus formed are driven through the freezing chamber by an auger rotating about a central axis into a distribution chamber located at the upper end of the freezing chamber. 
   In accordance with the present invention, the distribution chamber is defined by a concave ice distribution cap affixed to the top of the evaporator unit and defining an ice discharge opening which extends generally transversely to the axis of the auger. Ice units propelled by the auger enter the distribution chamber through a slotted comminution ring which operates to break the ice units into smaller pieces. 
   Located within the distribution cap is an upper bearing housing enclosing a bearing member for the auger and defining a slanted annular deflection surface which acts to divert the ice particles passing through the comminution ring in a direction radially outwardly relative to the axis of the auger. A slotted collar surrounding the comminution ring diverts the ice fragments upwardly toward the slanted annular surface. 
   Mounted atop the bearing housing is an impeller member having impeller blades which extend axially within the distribution chamber and which operate to drive the ice particles into the ice discharge opening upon rotation of the impeller member about the axis of the auger. Thus, the impeller blades operate to impart to the ice particles a force generally in alignment with the direction in which the ice units must travel in order to pass through the ice discharge opening thereby greatly reducing the tendency of the ice making assembly to clog or jam. 
   In accordance with a preferred embodiment of the invention, the impeller member should be formed of stainless steel to improve performance and reliability of operation. 
   Furthermore, the ice discharge opening in the ice discharge cap maybe formed to extend either in a direction radially outwardly from the axis of the auger or in a direction tangentially or circumferentially of the direction of rotation of the impeller blades. 

   
     DESCRIPTION OF THE DRAWINGS 
     Referring now to the drawings, wherein like reference numerals are used to refer to similar parts throughout the various figures thereof: 
       FIG. 1  is a perspective view partially broken away showing the evaporator unit in accordance with the present invention; 
       FIG. 2  is an exploded view showing in greater detail some of the parts of the evaporator unit of  FIG. 1 ; 
       FIG. 3  is a schematic diagram showing a refrigeration or condensing unit which may be used in the present invention; 
       FIG. 4  is a schematic diagram showing the evaporator assembly including an evaporator unit in accordance with the present invention; and 
       FIG. 5  is a top view of ice discharge cap in accordance with the present invention defining an ice discharge opening which extends in a circumferential direction. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Referring now to the drawings, and more particularly to  FIGS. 1 and 4 , there is shown an evaporator unit  10  in accordance with the present invention within which ice units are formed. The evaporator unit  10  is part of an evaporator assembly, shown schematically in  FIG. 4 , which is connected to operate in cooperation with a condenser assembly shown schematically in  FIG. 3 . 
   In the operation of the device of the invention, fresh or salt water is introduced into the evaporator unit  10  through a water supply conduit  12  which receives fresh or salt water from a reservoir  14 . It should be understood that when mounted on a marine vessel, the water supplied to the evaporator unit  10  may be ambient sea water if salt water ice is to be produced. Salt water ice would most likely be used on fishing vessels to store fish and the evaporator unit  10  would, of course, be made of corrosion resistant material, such as stainless steel. Furthermore, as will be apparent to those skilled in the art, the condenser or refrigeration assembly shown in  FIG. 3  would have to be of the type which could produce temperatures in the evaporator unit  10  which could freeze salt water. 
   The unit  10  includes refrigeration coils  16  which receive high pressure liquid refrigerant from the condenser assembly of  FIG. 3  through a refrigerant line  18  connected with a thermostatic expansion valve  20 . 
   Refrigerant flowing through the coils  16  is returned to a compressor  22  of the condenser assembly of  FIG. 3  as a low pressure gas through a suction line  24  and a low pressure control  26  where it is compressed to a high pressure gas and then directed through a line  28  to condensing unit  30  which converts the gas to a high pressure liquid. 
   The high pressure liquid is then returned from the condensing unit  30  to the coils  16  of the evaporator unit  10  by way of a line  31  through a receiver or storage chamber  32 , a high pressure control  34 , which senses the condensing temperature, and a liquid line dryer  36  which operates as a desiccant means to remove unwanted water. It should be noted that a line  37  connects the liquid line dryer  36  with the expansion valve  20  of the evaporator assembly. 
   The condensing unit  30  is an air cooled condenser with a water assist mechanism  38  which enables the unit  30  to operate more efficiently in a high ambient temperature environment. Particularly in marine applications, air cooling alone may not be sufficient due to high ambient temperatures and thus a water cooled assist is important. However, when lower ambient temperatures are in effect, such as when the marine vessel is docked or when the engines are not operating, the water assist cooling may be shut off and the device operated by air cooling alone to avoid introduction of sea weed and other contaminants into the water cooling system, which would be particularly problematic when the unit is unattended. 
   As shown in  FIG. 3 , the condensing unit includes a fan and motor assembly  40  which operates to cool the condenser  30  and which functions as the main cooling mechanism for the unit. 
   The evaporator assembly of  FIG. 4  should not be placed in the engine room of the marine craft since the heat of the engine will interfere with optimum functioning of the evaporator unit  10 . Thus, in accordance with one important aspect of the present invention, the condensing unit and the evaporator assembly are mounted separately on the marine craft and placed in different locations thus constituting a split system. 
   The evaporator unit of the invention is best seen in  FIG. 1  as comprising an outer insulating shell  42  surrounding a freezing chamber  44  within which a rotating auger  46  is mounted. The auger  46  is driven to rotate about a central axis  48  by a motor assembly  50  mounted together with the evaporator unit  10  upon a base  52 . 
   Water is introduced into the freezing chamber  44  through the conduit  12  from a water reservoir  14  with the water being turned into ice therein through the freezing effect of the coils  16 . As previously stated, the water may be fresh potable water or salt water depending upon the desired application. Of course, as will be apparent to those skilled in the art, the unit must be flushed out when converting from salt water use to fresh water. 
   As the water turns to ice, the ice is driven upwardly by rotation of the auger  46  into an ice distribution chamber  54  defined within an ice distribution cap  56  detachably mounted atop the evaporator unit  10 . A drain  80  is provided at the bottom of the evaporator unit  10  as a runoff for excess water. 
   Located within the chamber  54  is a comminution ring  58  having a series of slots  60  through which ice is driven by the auger  46  before entering distribution chamber  54 . The slots  60  operate to break the ice units entering the chamber  54  into smaller particles to facilitate further passage of the ice to its ultimate destination. 
   A slotted collar  62  extending around the comminution ring  58  and mounted on a ring  63  operates to direct ice passing through the slots  60  upwardly. Holes  64  and  66  formed in the collar  62  and the ring  63 , respectively, are adapted to receive connecting means such as bolts (not shown) to attach the collar  62  to the ring  63 . 
   Located within the chamber  54  is an upper bearing housing  68  within which is located an upper bearing mechanism (not shown) for the auger  46 . The bearing housing  68  is configured to define a slanted annular wall  70  which acts to divert in a radially outward direction ice particles passing through the slots  60  in the ring  58 . 
   Mounted on the bearing housing  68  is an impeller member  72  having axially extending impeller blades  74  arranged to rotate about die central axis  48  of the evaporator unit  10 . As will be apparent from the drawings, the impeller blades have a relatively narrow elongated configuration extending longitudinally generally parallel to the axis  48 . The impeller member  72  is preferably made of a noncorrosive material, such as stainless steel or titanium. 
   The ice distribution cap  56  is formed with a concave interior which defines and encloses the ice distribution chamber  54 . The distribution cap  56  is also formed with a tubular member  76  which defines an ice discharge opening  78  through which ice may exit the distribution chamber  54 . 
   In the operation of the device of the present invention, ice formed in the freezing chamber  44  is driven upwardly by the rotating auger  46  through the slots  60  in the comminution ring  58  where the ice is fragmented before it enters the distribution chamber  54  thereby to facilitate conveying of the ice particles into the ice discharge opening  78 . 
   As the ice passes through the slots  60  it is directed upwardly by the slotted collar  62  against the slanted annular wall  70  whereby it is diverted in a radially outward direction. 
   As the ice moves further into the distribution chamber  54  it is engaged by the sweeping fingers or impeller blades  74  of the rotating impeller member  72  whereby the ice has imparted thereto a force extending in a circumferential and radial direction in order to facilitate flow of the ice into the tubular member  76  and through the ice discharge opening  78 . The ice distribution cap  56  is formed with an interior wall  57  having a generally circular configuration which cooperates with the blades  74  of the impeller member  72  to facilitate movement of the ice into and through the distribution opening  78 . 
   It will be apparent that as the ice first enters the distribution chamber  54  it has had imparted thereto an axially directed force by the auger  46 . However, in order for the ice to enter and pass through the discharge opening  78  it must undergo a change of direction of approximately 90°. Furthermore, if the ice is to be delivered to a remote location, flexible tubing or similar conduit means (not shown) extending to the remote location through which the ice must flow must be attached at the end of the tubular member  76  to receive the ice flowing through the discharge opening  78 . 
   As a result of the need to change the flow direction which is imparted to the ice by the auger  46  and due to the flow resistance which is created by the flexible conduit, a reactive force is imparted to the rotating auger  46 . If there are no means between the auger  46  and the discharge opening  78  to assist in changing the direction of ice flow and in overcoming the resistance which is created as a result of having to move the ice through a length of conduit, the ice will tend to accumulate above the auger  46  thereby causing jamming of the device due to the inability of the auger  46  to overcome the flow resistance thus created. As a result the entire device would have to be shut down and the accumulated ice cleared away manually. 
   The device of the present invention reduces the tendency for ice to accumulate above the auger  46  and thereby reduces the tendency for the device to jam and necessitate shut down. 
   The comminution ring  58  with the slots  60  makes it easier to move the ice through the distribution chamber  54  by reducing the size of the ice particles leaving the auger  46 . The slanted surface  70  assists in diverting the ice flow from an axial direction to a radial direction in better alignment with the direction which the ice must take to pass through the discharge opening  78 . After the ice passes through the comminution ring  58  and is diverted by the slanted surface  70 , it is engaged by the blades  74  of the rotating impeller member  72  whereby the ice is further driven into the discharge opening  78 . 
   It will be noted that the impeller member not only provides an added driving force to the ice, but that it does so in a direction more in line with the direction in which the ice must flow too pass through the ice discharge opening  78 . Thus, the impeller member  72  not only boosts the driving force needed to move the ice out of the distribution chamber  54 , but it does this in a manner which facilitates changing the direction of the ice flow leaving the end of the auger  46 . 
   In the embodiment shown in  FIGS. 1 and 2 , the member  76  is arranged to define the ice discharge opening  78  to extend from the distribution cap  56  in a direction radially relative to the axis  48 . However, in accordance with a further embodiment of the invention, the ice discharge opening may be defined to extend tangentially relative to the direction of rotation of the impeller member  72 . This embodiment is shown in  FIG. 5  wherein an ice distribution cap  56   a  is formed with a tubular member  76   a  defining an ice discharge opening  78   a  extending in a direction tangential to the direction of rotation of the auger  46 . This embodiment makes it easier for the ice to pass through the discharge opening  78   a  since it is in better alignment with the direction of travel imparted to the ice by the rotating blades  74  of the impeller member  72 . 
   It should be noted that the ice distribution cap  56 ,  56   a  is formed with a domed configuration having a hollow interior whose wails define the distribution chamber  54  with a circular component which cooperates with the rotating impeller blades  74  to facilitate movement of the ice out of the chamber  54  and into the discharge opening  78 ,  78   a.    
   While the present invention has been described by reference to specific embodiments thereof, it should be understood that the invention may be embodied otherwise without departing from the spirit and scope of the invention as defined in the following claims.