Abstract:
A cryogen injection apparatus for injecting a cryogenic substance to a blender includes at least one nozzle constructed for being in fluid communication with an interior of the blender; a heat transfer fluid for being operationally associated by conduction with the at least one nozzle; and a heat transfer housing supporting the at least one nozzle and having a space therein for receipt of the heat transfer fluid to warm the at least one nozzle. A related method is also provided.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present embodiments related to nozzle apparatus that introduce cryogen substances into food products for chilling and/or freezing same, and which apparatus are not clogged from use of the cryogenic substance. 
         [0002]    The bottom injection of cryogen into mixers for cooling food products, for example, are known. Such known bottom injection nozzles for cryogenic substances, such as for example liquid nitrogen (LIN), encounter difficulties when being used with wet products which are drawn into an orifice of the nozzle in communication with the food processing equipment, whereupon the wet food product is frozen upon exposure to the cryogen. When such a situation occurs, the nozzle orifice will become restricted and eventually clogged. Unfortunately, it is extremely difficult to clear the nozzle and no further cooling cryogenic substance can be delivered to the mixer for chilling until the clog is removed. 
         [0003]    Existing nozzle structure contributes to this deficiency. That is, known nozzles are made from either thick stainless steel, which transfers a large amount of heat from the mixture or blender wall and thereafter remains cold after an injection cycle of the cryogen until the mixing is complete. This type of stainless steel nozzle contributes to the clogging situation when the cryogenic substance, such as LIN for example, is exposed to the wet product in the blender or mixer. 
         [0004]    Other nozzles are manufactured with a teflon sleeve which reduces the amount of heat transfer from the blender wall to the nozzle, but such nozzles are susceptible to migration of the food product between the sleeve and the housing and will therefore crack the nozzle due to thermal expansion and contraction from the cryogenic substance. 
       SUMMARY OF THE INVENTION 
       [0005]    There is therefore provided a low thermal mass straight bore (or expanding bore) nozzle with an integrated heating system which will provide for quick warming or thawing of the nozzle, therefore clearing of any product within the nozzle between injection cycles of cryogen from the nozzle. The present nozzle embodiments also eliminate cracking of the nozzle because an internal sleeve for the nozzle has been eliminated in the present embodiments. 
         [0006]    There is provided a cryogen injection apparatus for injecting a cryogenic substance into a blender, which includes at least one nozzle constructed for being in fluid communication with an interior of the blender; a heat transfer fluid for being operationally associated by conduction with the at least one nozzle; and a heat transfer housing supporting the at least one nozzle and having a space therein for receipt of the heat transfer fluid to warm the at least one nozzle. 
         [0007]    There is also provided a method for heat transfer of an injection nozzle providing a cryogenic substance to a blender, which includes supporting the injection nozzle at a wall of the blender for being in communication with an interior of said blender; and providing heat transfer with a fluid to said injection nozzle. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    For a more complete understanding of the present invention, reference may be had to the following description of exemplary embodiments considered in connection with the accompanying drawing Figures, of which: 
           [0009]      FIGS. 1-2  show side and perspective views, respectively, of the cryogen injection nozzle embodiment of the present invention; 
           [0010]      FIG. 3 . shows a perspective, exploded view of the embodiment of  FIGS. 1 and 2 ; 
           [0011]      FIGS. 4A-4B  show top and side cross-section views, respectively, of certain elements of the embodiment of  FIG. 3 ; 
           [0012]      FIG. 5 . shows a perspective, partial-transparent view of another embodiment of the injection nozzle; and 
           [0013]      FIG. 6 . shows a side view partially in cross-section of the nozzle embodiment of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0014]    Before explaining the inventive embodiments in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. 
         [0015]    Referring to  FIGS. 1-3 , an injection nozzle apparatus of a first embodiment of the present invention is shown generally at  10  mounted to a wall  12  of a blender or mixer (not shown) in which food product (not shown) is disposed for being chilled. While food product is referred to for being treated by the injection nozzle  10 , it is understood that other types of product can be treated with the present injection nozzle embodiment. 
         [0016]    The injection nozzle  10  consists of a nozzle or nozzle portion  14 , a heat sink member  16 , a flow block member  18  and an outer cover  20  or housing. A mechanical fastener such as for example a nut  21  removably mounts the heat sink member  16  to the nozzle portion  14  as discussed below. The nozzle portion  14  delivers liquid nitrogen, such as LIN, into the blender. The nozzle  14  can be either a straight bore stainless steel tube or a machined steel tube with an expanding bore, wherein a diameter of the bore increases along the flow path in the direction of the wall  12 . The nozzle  14  is constructed from a material that has a low thermal mass. 
         [0017]    Referring also to  FIGS. 4A and 4B , the heat sink member  16  is used to transfer heat to the blender wall  12  and the nozzle  14 . The heat sink member  16  is constructed with a spiral fin  17  for providing a continuous spiral path  19  of the heat sink member  16  as shown for example in  FIGS. 3 and 4A , so that any applied heat transfer fluid  22  must travel through the spiral path  19 . A higher velocity of the heat transfer fluid  22  through the spiral path  19  will provide for an increase in heat transfer between the wall  12  and the heat sink member  16 . The heat transfer fluid  22  is discharged from the heat sink member  16  along an axial orientation of the nozzle  14  and then out of the housing  20 . Heat is first transferred into the wall  12  and then to the nozzle  14 . A thermal mass of the wall  12  is greater than a thermal mass of the nozzle  14 . Therefore, any of the heat transfer fluid  22  with a sufficient temperature and thermal conductivity can be used, such as for example water, steam, air, hot gas, etc. 
         [0018]    Referring in particular to  FIGS. 2-3 , the flow block member  18  includes an inlet port  24  and an outlet port  26 . The housing  20  also includes a inlet port  28  and outlet port  30 . When the injection nozzle  10  of for example  FIG. 3  is assembled into what is represented at  FIG. 2 , the inlet ports  24 ,  28  can be, although do not have to be, in registration with each other, while the outlet ports  26 ,  30  can be, although do not have to be, in registration with each other to provide for the flow of the heat transfer fluid  22  into the spiral path  19  for providing heat transfer and to ultimately be exhausted from the outlet port  30 . The flow block member  18  is used to contain and direct the flow of the heat transfer fluid  22  to the heat sink member  16  and through the spiral path  19 . 
         [0019]    The housing  20  retains the heat sink member  16  and the flow block member  18  as being releasably mounted together and protects the injection nozzle  10  from external pressure water sprays and cleaning agents. 
         [0020]    The nozzle portion  14  may be constructed from stainless steel; the heat sink member  16  may be constructed from brass, copper or any other material having high thermal conductivity; the flow block member  18  may be constructed from stainless steel or plastic; and the outer cover or housing  20  may be constructed from stainless steel. 
         [0021]    The injection nozzle  10  of the embodiment showing in  FIGS. 1-4B  permits the nozzle to be easily cleaned, because the only elements of the nozzle exposed to an interior of the blender is an interior of the nozzle portion  14 . Therefore, hot water or other cleaning solutions can be sprayed through the nozzle portion  14  for easy cleaning without having to disassemble the injection nozzle  10 . 
         [0022]    Referring to  FIGS. 1, 3 and 4A-4B , the flow of the heat transfer fluid  22  is as follows. The heat transfer fluid  22  is introduced into the inlet port  28  of the outer cover  20  and flows through the inlet port  24  of the flow block  18 . The inlet ports  24 ,  28  may be in registration with each other in order to facilitate the flow of the heat transfer fluid  22 . The heat transfer fluid  22  is thereafter introduced into the spiral path  19  of the heat sink member  16  which is seated within the flow block  18 , for the fluid to move along the spiral path  19  where heat transfer occurs for the nozzle  14  and the wall  12  of the blender. Upon completion of the heat transfer fluid  22  travelling along the spiral path  19 , the fluid is directed back into the flow block  18  whereupon the fluid exits the block from the outlet port  26  as shown in  FIG. 3 . The outlet port of the flow block member  18  may be in registration with the outlet port  30  of the outer cover  20 , when the flow block member  18  is seated within the outer cover  20  such that the fluid  22  can be exhausted quickly from the heat sink member  16  and the flow block  18 . 
         [0023]    The heat sink member  16 , the flow block member  18  and the outer cover  20  each have a corresponding central axial hole  16   a,    18   a,    20   a,  respectively, as shown for example in  FIG. 3  which, when such elements are mounted to the nozzle  14 , are in registration with each other so that the injection nozzle apparatus  10  can be mounted to the wall  12  as shown in  FIGS. 1-2 . The nozzle portion  14  extends through the wall  12  of the blender and has an exterior threaded surface area  15 , as shown. The nozzle portion  14  is disposed through the central axial hole  16   a  of the heat sink member  16  and the mechanical fastener, such as the nut  21 , is threaded to the threaded area  15  of the nozzle  14 . The flow block member  18  is seated by friction fit or crimping to the heat sink member  16 , and the outer cover  20  may be similarly mounted to the flow block  18 . An alternate embodiment can have a mechanical fastener  21   a  (a nut) positioned as shown to threadably engage the nozzle portion  14  where it protrudes through the central axial hole  20   a  of the outer cover  20 . In such an embodiment, the nozzle portion  14  has a threaded surface area at that portion protruding from the outer cover. With this embodiment, the apparatus  10  can be fabricated as a single, integral unit to be mounted to the wall  12  of the blender. 
         [0024]    In operation with the blender (not shown), a batch of food product, such as for example ground meat with ingredients therein, is placed in the blender which is started such that internal blades (not shown) of the blender mix the food product and ingredients. It is required to chill the meat during the blending operation and therefore, cryogen such as liquid nitrogen (LIN) is injected into the blender through the injection nozzle  10 . That is, the LIN is injected through the nozzle portion  14  during which heat is transferred from the wall  12  via conduction with the nozzle portion  14  which also has its temperature reduced to a temperature substantially similar to that of the LIN. Minimal heat is transferred between the wall  12  and the nozzle portion  14  due to a low thermal mass of the nozzle portion. When a desired, reduced temperature of the meat is obtained, the LIN injection is stopped and the meat is removed from the blender. The heat transfer fluid  22  is introduced into the inlet port  28  of the outer cover  20  as explained above to rapidly thaw the injection nozzle  14 . Any meat or water trapped within the nozzle portion  14  is warmed and can be easily discharged at a start of the next batch of food product being used in the blender. That is, because the nozzle  14  has been warmed and therefore, thawed by the heat transfer fluid  22  circulating through the spiral path  19  of the heat sink member  16 , the next injection of LIN through the nozzle portion  14  will forceably expel any trapped food product or water, or clog of such, into the blender. The next batch of meat is thereby loaded into the blender and the process continues. The construction of the injection nozzle apparatus  10  permits clean-in-place (CIP) of the nozzle portion  14  without removal or disassembly of the apparatus. 
         [0025]    Referring to  FIGS. 5-6 , another embodiment of the injection nozzle apparatus is shown generally at  100  mounted to a wall  102  of a blender or mixer (not shown). In this embodiment, water is used to defrost or thaw the apparatus  100  and the wall  102  after an injection cycle of LIN is introduced to the blender. 
         [0026]    The injection nozzle apparatus  100  includes a housing  104  or enclosure which can be manufactured from stainless steel. The housing  104  includes a plurality of sidewalls, one of such sidewall  106  having a surface area substantially conforming to a shape of an exterior surface of the wall  102 . The sidewall  106  permits the housing  104  to lie flush against an exterior surface  108  of the wall  102 . The sidewalls of the housing  104  define a space  109  or chamber therein. An inlet port  110  is provided at an upper sidewall of the housing  104 , while an outlet port  112  is provided at a lower one of the sidewalls of the housing. A heat transfer fluid  114 , such as for example water, is introduced into the inlet port  112  and therefore into the space  109  after which the fluid can be removed from the space through the outlet port  112 . 
         [0027]    The sidewalls of the housing  104  may be arranged to provide an extended portion  116  through which at least one cryogen injection nozzle  118  extends and through the space  109  and the wall  102  for opening into the blender where food product  120  is being chilled. The extended portion  116  provides a larger volume of the space  109  only where the injection nozzle(s)  118  are disposed so that heat transfer is more thorough, uniform, and occurs more quickly. It is not necessary to have the remainder of the space  109  to be sized similar to that of the extended portion  116 . The cryogen may be liquid nitrogen (LIN). In the embodiment shown in  FIGS. 5-6 , there are a pair of the injection nozzles  118 , but it is understood that one or a plurality of the nozzles can be used depending upon the amount of LIN to be introduced into the blender and the nature or type of the product  120  being processed therein. 
         [0028]    During operation, the heat transfer fluid  114 , such as water for example, is purged from the space  109  of the housing  104 , and a cryogen injection cycle begins having a duration of approximately 6 to 8 minutes, during which occurs LIN injected through the nozzles  118  to the food product  120  in the blender. When the injection cycle stops, the heat transfer fluid  114 , in this case water, is introduced into the space  109  from the inlet port  110  at a rate of approximately 10-30 L/hr. for a period of from six to twelve minutes. The water will defrost or thaw the injection nozzle(s)  118  and the surface  108  and wall  102  in close proximity to the sidewall  106 . Accordingly, there should be no frozen food product or condensate in the injection nozzle  118 . Any frozen product or moisture in the injection nozzle(s)  118  has been warmed to a temperature sufficient to eject same into the blender at the next LIN injection cycle. The water  114  is then purged from the space  108  of the housing  104  and a subsequent cryogen cycle begins. The tubing of the injection nozzle  118  or nozzles permits clean-in-place (CIP) of the nozzle without removal of same from the housing  104 . Valving (not shown) operatively associated with the outlet port  112  can be used to retain the heat transfer fluid  114  to a specific depth or amount in the space  109  to carry out the heat transfer effect of the nozzles ( 118 ). 
         [0029]    It will be understood that the embodiments described herein are merely exemplary, and that one skilled in the art may make variations and modifications without departing from the spirit and scope of the invention. All such variations and modifications are intended to be included within the scope of the invention as described and claimed herein. Further, all embodiments disclosed are not necessarily in the alternative, as various embodiments of the invention may be combined to provide the desired result.