Abstract:
A food processing vat is provided with a vent that can be automatically cleaned in place, without requiring manual cleaning by a technician or removal of the vent from the vat. A nozzle is mounted to at least one of the vent and the vat and has an opening(s) that is posited with respect to the vent to direct cleaning fluid into the vent. The vent may include a canister that concentrically surrounds at least a portion of a vent tube that is fluidly connected to the vat, which collects cleaning fluid and/or condensate from gas that enters or exits the vat.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of and claims priority from U.S. Provisional Patent Application Ser. No. 61/325,612 filed on Apr. 19, 2010, the entirety of which is expressly incorporated by reference herein. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to food processing vats and, more particularly, to vents that are used with food processing vats. 
     2. Discussion of the Related Art 
     Vents that are mounted to food processing vats are known in the food processing industries. Such vents fluidly connect an inside space within the vat to the ambient. 
     Clean-in-place systems for use with food processing vats are also known in the food processing industries. Such clean-in-place systems automatically spray cleaning fluid, in liquid form, inside of food processing vats. 
     SUMMARY OF THE INVENTION 
     The inventors have recognized that in typical food processing vats, the clean-in-place systems have been primarily designed to clean the inside walls of the vat and large mechanicals that are housed in the vat, such as agitator shafts, while other parts of the overall vat systems have not been cleaned with these clean-in-place systems. The inventors have also recognized that in typical food processing vats, vents must be manually cleaned by technicians and, at times, require removal of the vents for thorough cleaning, which can be substantially time consuming. The inventors have further recognized that typical vents have side walls with relatively small surface areas upon which to condense out water or other condensate from the vapor or vented fluid that flows out of the vat. The present invention contemplates a vent for a food processing vat that addresses these and other problems and drawbacks of the prior art. 
     In accordance with an aspect of the invention, a food processing vat system is provided with a vent that is attached to a vat and fluidly connects an inside space of the vat to the ambient so as to maintain a pressure within the vat at an ambient pressure and/or to direct a vented fluid that flows out of the vat to the ambient. A nozzle that is configured to convey a cleaning fluid through it is mounted to at least one of the vent and the vat, and may be mounted in a generally fixed position. The nozzle has an opening that is positioned with respect to the vent so that the nozzle directs the cleaning fluid into the vent while the vent remains attached to the vat. This allows the vent to be cleaned in place, without requiring manual cleaning by a technician. 
     In accordance with another aspect of the invention, the nozzle is positioned inside of the vent. The vent may define a vent body having an upper edge and the nozzle may be positioned below the upper edge of the vent body. The vent may include a lid, and the vent may further include a nozzle tube that extends through the lid and holds the nozzle inside of the vent. This may also allow the vent to be cleaned in place, without requiring manual cleaning by a technician. 
     In accordance with another aspect of the invention, the vent defines a vent body and a lid that is positioned with respect to the vent body such that (i) vented fluid that flows out of the vat can flow between the vent body and the lid so that the vented fluid can exit the vent, and (ii) cleaning fluid that is delivered out of the nozzle cannot flow between the vent body and the lid so that the cleaning fluid remains in the vent body or flows into the vat. The lid may include a lid lower portion that longitudinally overlaps at least part of an upper end of the vent body and is transversely spaced from the upper end of the vent body. A lid upper portion may be spaced from the upper end of the vent body. The lid may be maintained by spring clips in such a position with respect to the vent body. This may allow the vented fluid that flows out of the vat to be directed to the ambient while maintaining any cleaning fluid that is sprayed in the vent to remain in the vent or flow into the vat. 
     In accordance with another aspect of the invention, the vent further includes a collar that is positioned with respect to the nozzle and the lid so that the cleaning fluid that is delivered out of the nozzle is deflected by the collar to prevent the cleaning fluid from exiting the vent. The collar may be connected to and extend downwardly from a lower surface of the lid, spaced radially inside of an outer perimeter of the lid. The vent body may include a tube that is housed concentrically inside of a canister, and the collar may be concentrically aligned between the tube and container. This may allow the collar to deflect cleaning fluid that is delivered from the nozzle so that the cleaning fluid remains in the vent body or flows into the vat, without spraying outside of the vent. 
     In accordance with another aspect of the invention, the vent is removably attached to the vat. The vent may be attached to the vat with a clamp that holds a pair of flanges that are provided at respective ends of the vent tube, and a vat tube that is fixed to the vat. This may permit quick removal of the vent from the vat for occasional servicing and maintenance. 
     In accordance with another aspect of the invention, the vent tube extends between the vat or vat tube and the lid of the vent, directing the vented fluid from the vat to the vent. A lower portion of the vent tube may extend beyond the canister and define a solid side wall. An upper portion of the vent tube may be provided within the canister and may have a perforated side wall. The openings or perforations of the perforated side wall may be configured to diffuse streams of the cleaning fluid that is delivered by the nozzle, so that the cleaning fluid is spread out and applied to substantially an entire inner surface(s) area of the vent. This may allow a nozzle to be used near the walls of the vent while delivering cleaning fluid across substantially the entire walls of the vent. 
     In accordance with another aspect of the invention, the canister extends concentrically around the vent tube so as to define an annular passage between the vent tube and the canister and through which the vented fluid can flow. The canister may further include a lower wall that extends generally radially toward and connects to the vent tube. The lower wall of the canister may connect to the vent tube at a location on the vent tube that generally defines a division line between the solid side wall of the vent tube and the perforated side wall of the vent tube. This may allow the cleaning fluid to be diffused through the perforated side wall of the vent tube, spreading out its application through the vent, while retaining the cleaning fluid within the vent or allowing it to flow into the vat. 
     According to another aspect of the invention, the canister lower wall is slanted so that different depths of the annular passage are defined at different locations about a periphery of the vent tube. The slanted lower wall may extend angularly with respect to the canister side wall so that corresponding portions of the slanted lower wall, vent tube, and canister side wall define a collection chamber that can collect condensate that condenses out of the vented fluid. The collection chamber may also collect the cleaning fluid that remains in the vent and does not flow into the vat. The vent may include a drain that extends through the canister side wall at a location that corresponds to a deepest portion of the annular passage. This may allow removal of condensate, including water and non-water materials that may be suspended in the vented fluid, the cleaning fluid, and/or other substances that may collect in the collection chamber to be removed from the vent. 
     Various other features, objects, and advantages of the invention will be made apparent from the following description taken together with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings illustrate the best mode presently contemplated of carrying out the invention. 
       In the drawings: 
         FIG. 1  is an isometric view from above and in front of a vat system incorporating a clean-in-place vent in accordance with the present invention; 
         FIG. 2  is an isometric view from above and in back of the vat system of  FIG. 1 ; 
         FIG. 3  is a top plan view of the vat system of  FIG. 1 ; 
         FIG. 4  is a front elevation view of the vat system of  FIG. 1 ; 
         FIG. 5  is a sectional view of the vent of the vat system of  FIG. 1 , taken at line  5 - 5  of  FIG. 4 ; and 
         FIG. 6  is a sectional view of the vent of the vat system of  FIG. 1 , taken at line  6 - 6  of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIGS. 1 and 2  illustrate a vat system  5  that can be used for processing food and related products (collectively referred to as “vat contents”) by mechanically manipulating and heating or cooling the vat contents, depending on the particular food or related product being processed. In a representative application, the vat system  5  may be used in the production of cheese, although it is understood that the vat system  5  may be used in processing other types of food products. The vat system  5  includes a vat  7  that has an agitation system  40  which performs the mechanical manipulation tasks by rotating a pair of shafts upon which blade assemblies are mounted, and a zoned heat transfer system  50  to perform heating and/or cooling to provide zoned temperature control to the vat  7 . 
     Vat  7  defines an enclosure having a top wall  10 , a bottom wall  11 , and side walls  14 ,  15 , all of which extend longitudinally between a pair of end walls  18  and  19 . The walls  10 ,  11 ,  14 ,  15 ,  18 ,  19  are multilayered, having an outer jacket  20  and an inner shell  25  that are spaced from each other. Insulation and various components of the zoned heat transfer system  50  are housed between the jacket  20  and shell  25 . The shell  25  is the innermost structure of the vat  7 , so that its inner surface surrounds and defines an outer periphery of a void or inside space  8  within the vat  7 . A lower part of the inside space  8  resembles two horizontal parallel cylinders that transversely intersect each other, being defined by a lower portion of the shell  25  that has a pair of arcuate depressions which extend along the length of the vat  7 , on opposing sides of a longitudinally extending raised middle segment. From the lower portion of the shell  25 , opposing side portions extend in an outwardly bowed manner, arching away from each other in a transverse direction of the vat  7 . An upper portion of the shell  25  arcs gradually between side portions of the shell  25  and defines an upper perimeter of the inside space  8  of vat  7 . 
     Referring now to  FIGS. 1-4 , operation of the zoned heat transfer system  50  alters the temperature of the inside space  8  of vat  7 , which correspondingly changes a volume of the gases within the inside space  8  of vat  7 . Vent  60  allows the vat  7  to breathe, accommodating the changing volume of gases without changing a pressure within the vat  7  so as to keep the pressure of the inside space  8  of the vat at the ambient pressure. 
     Referring now to  FIGS. 5 and 6 , vent  60  includes a vent body  62  that is defined by a vent tube  70  and a container or canister  80 , and a lid  100  that sits over the vent body  62 . A nozzle  90  that sprays a cleaning fluid, which may be in a liquid form, is positioned with respect to the vent tube  70 , canister  80 , and lid  100  so that the cleaning fluid that exits the nozzle  90  either remains in the vent  60  or flows into the vat  7 , described in greater detail elsewhere herein. 
     Still referring to  FIGS. 5 and 6 , in this embodiment, the vent  60  is attached to the vat  7  by coupling the vent tube  70  to a vat tube  55 . Vat tube  55  is connected at its bottom end to the top wall  10  of the vat  7 . A flange  56  is connected to the top end of the vat tube  55 . Flange  56  sits below a cooperating flange  71  that is connected to the bottom of vent tube  70 , and a seal  58  sits between the flanges  56 ,  71  of the vat and vent tubes  55 ,  70 , respectively. A lower surface of flange  56  and an upper surface of flange  71  are angled toward each other. Correspondingly, a cross-sectional profile shape of the flanges  56 ,  71  together is wedge-shaped, tapering down from a thicker portion adjacent the vat and vent tubes  55 ,  70 , respectively, to a thinner portion that is radially furthest from the vat and vent tubes  55 ,  70 , respectively. A clamp  57  ( FIG. 5 ) fits around and engages both of the flanges  56 ,  71  and pushes them toward each other to compress the seal  58  to provide a liquid-tight joint between the vat and vent tubes  55 ,  70 , respectively. Removal of the clamp  57  from the flanges  56 ,  71  allows the vent  60  to be detached from the vat  7  by lifting the vent away from the vat tube  55 . 
     Still referring to  FIGS. 5 and 6 , in this embodiment, a lower portion  72  of the vent tube  70  extends upwardly from the flange  71 , toward the canister  80 . Lower portion  72  has a solid side wall  73  which ensures that the vented fluid flows in a generally longitudinal direction through the lower portion  72 , without escaping the confines of the lower portion  72  of the vent tube  70 . 
     An upper portion  75  of the vent tube  70  connects to and extends upwardly from the lower portion  72 . The upper portion  75  in this embodiment has a length that is over half of the overall length of the vent tube  70 , the upper portion  75  being about four times longer than the lower portion  72 . In another embodiment, the upper portion  75  may be about two times longer than the lower portion  72 . A side wall  76  of upper portion  75  is perforated with openings  77  that extend entirely through the thickness of the side wall  76  and that are spaced at substantially equal distances from each other to provide a matrix or array of openings  77  that define the perforation(s). 
     The perforated side wall  76  of the upper portion  75  of the vent tube  70  allows the vented fluid that flows out of the lower portion  72  to flow in both a generally longitudinal direction through the upper portion  75  and also in a generally radial direction out of the openings  77 . In so doing, a portion of the vented fluid flows through the entire length of the upper portion  75  and exits out of the vent tube  70  through an opening defined at an upper perimeter edge of the upper portion  75  with its further longitudinal flow being impeded by the overlying lid  100 . The rest of the vented fluid diffuses and radially flows through the openings  77  of the perforated side wall, with its further radially directed flow being impeded by the canister  80 . 
     Still referring to  FIGS. 5 and 6 , canister  80  includes a solid side wall  81  that extends concentrically around the vent tube  70 , so as to define an annular passage  78  between the vent tube  70  and the canister  80 . The annular passage  78  provides a path through which the vented fluid flows in a longitudinal direction while exiting the vent  60 , after flowing in the radial direction into the annular passage  78  from the vent tube  70 . A diameter of the flow path through the vent  60  which is defined by the solid side wall segments that radially restrict flow through the vent  60 , namely, the side walls  73  and  81 , has a step-change increase in which the relatively smaller diameter of the side wall  73  of the vent tube lower portion  72  increases to a relatively larger diameter of the side wall  81  of the canister  80 . Such diameter increase occurs generally at a lower wall  82  of the canister  80 . 
     Lower wall  82  of the canister  80  has an annular perimeter shape and extends radially between the vent tube  70  and canister side wall  81 . Lower wall  82  connects the canister side wall  81  to the vent tube  70  at a location that generally defines a division line between the solid and perforated side walls  73 ,  76 , respectively, of the upper and lower portions  72 ,  75 , respectively, of the vent tube  70 . 
     In this embodiment, the canister lower wall  82  is slanted, extending angularly with respect to the tube and canister side walls  73 ,  76 ,  81 . This provides the annular passage  78  with different depths at different locations about the perimeter of the vent tube  70 . A collection chamber  85  is defined by a space between respective portions of the slanted lower wall  82 , vent tube  70 , and canister side wall  81  that can collect condensate that condenses out of the vented fluid and/or cleaning fluid that is delivered out of nozzle  90 . 
     The particular volume of condensate, cleaning fluid, or other liquid that the collection chamber  85  holds is determined at least in part by (i) the width of the lower wall  82  and thus the radial distance between the vent tube  70  and canister  80 , and (ii) the particular location of the division line between the solid and perforated side walls  73 ,  76 , respectively, of the upper and lower portions  72 ,  75 , respectively, of the vent tube  70  and thus a maximum height at which contents in the collection chamber  85  can be held and over which the contents will spill through the openings  77  of the perforated side wall  76  and run down the inside of vent tube  70  and into the vat  7 . In this embodiment, the diameter of the canister  80  is about 25 percent larger than the diameter of the vent tube  70 , although it is understood that any other satisfactory differential may be employed. Also in this embodiment, the division line between the solid and perforated side walls  73 ,  76 , respectively, of the upper and lower portions  72 ,  75 , respectively, of the vent tube  70  extends orthogonally with respect to a longitudinal axis of the vent tube  70 , whereby the division line is not slanted like the orientation of the canister lower wall  82 . In another embodiment, the division line between the solid and perforated side walls  73 ,  76 , respectively, of the upper and lower portions  72 ,  75 , respectively, of the vent tube  70  may extend parallel to the canister lower wall  82 . 
     Still referring to  FIGS. 5 and 6 , regardless of the particular location of the division line between the solid and perforated side walls  73 ,  76 , respectively, of the upper and lower portions  72 ,  75 , respectively, of the vent tube  70 , the collection chamber  85  includes a drain  87  that extends though the canister side wall  81 . The drain  87  of this embodiment is provided at a location upon the canister side wall  81  that corresponds to a deepest portion of the annular passage  78  and thus at the bottom of the collection chamber  85 . The drain  87  allows removal of condensate, including liquid and non-liquid materials that may be suspended in the vented fluid, the cleaning fluid, and/or other substances that may collect in the collection chamber  85 , to be removed from the vent  60 . Still referring to  FIGS. 5 and 6 , the cleaning fluid that may collect in the collection chamber  85  is that which is delivered from nozzle  90  during a clean-in-place procedure. Nozzle  90  is positioned with respect to the vat system  5  so that its opening(s)  91  directs cleaning fluid into the vent  60  while the vent remains attached to the vat  7 .  FIG. 6  shows another nozzle  90  that is mounted to the top wall  10  of the vat and has openings  91  provided about its outer surface so as to direct cleaning fluid in multiple directions, so that some of the cleaning fluid may enter the bottom opening of the vat tube  55  and may deflect into the vent  60 . 
     Still referring to  FIGS. 5 and 6 , in this embodiment, toward the top of the vent  60 , one of the nozzles  90  that can spray cleaning fluid is mounted fully inside of the vent  60 . This nozzle  90  is positioned below an upper edge of the vent body  62  and is substantially aligned with a longitudinal axis of the vent  60  and thus concentrically inside of the perforated side wall  76  of the upper portion  75  of vent tube  70 . With the nozzle  90  mounted in this position with respect to the perforated side wall  76 , the discrete streams of cleaning fluid leaving the openings  91  can be split into more streams that deflect in different directions while being sprayed through the openings  77  of the perforated side wall  76 , diffusing the cleaning fluid and spreading out its application through the vent  60 . 
     Referring now to  FIG. 6 , in this embodiment, the nozzle  90  is mounted to and suspended from the lid  100  with a nozzle tube  92 . The nozzle tube  92  extends through a flange that is raised above the rest of the lid  100  with a tube segment that extends above and below the lid  100 . An end of the nozzle tube  92  that is outside of the vent  60  has a flange that couples to a corresponding flange of a cleaning fluid supply line  95 , allowing such flanges to be uncoupled from each other to separate the nozzle tube  92  from the cleaning fluid supply line  95  while leaving the nozzle tube  92  connected to the lid  100 . The cleaning fluid supply line  95  is connected to a known clean-in-place system (including suitable plumbing components, hardware components, and controls) that is configured to deliver cleaning fluid for automatically spraying down predetermined surfaces within the vat system  5 . 
     Referring again to  FIGS. 5 and 6 , the lid  100  is dished out, presenting a convex upper surface and a concave lower surface, with a lower lip  102  provided at a lower portion  105  of the lid  100  and extending downwardly from its outer perimeter. The lid  100  is positioned with respect to the vent body  62  such that (i) vented fluid that flows out of the vat  7  can flow between the vent body  62  and the lid  100  so that the vented fluid can exit the vent  60 , and (ii) cleaning fluid that is delivered out of the nozzle  90  cannot flow between the vent body  62  and the lid  100  so that the cleaning fluid remains in the vent body  62  or flows into the vat  7 . The lip  102  of the lower portion  105  longitudinally overlaps at least part of an upper end of the vent body  62  and is transversely spaced from the upper end of the vent body  62 . A lid upper portion  110  is spaced longitudinally from the upper end of the vent body  62 . 
     The lid  100  of this embodiment is maintained in this overlying and longitudinally and radially-spaced relationship with respect to the vent body  62  by spring clips  120 . In this embodiment, the spring clips  120  are connected to and extend upwardly from an upper edge of the vent tube  70 . Spring clips  120  are bent and generally L-shaped and have an upright segment that aligns with the vent tube  70  and a horizontal segment that engages an inner circumferential surface of a collar  125 . 
     Still referring to  FIGS. 5 and 6 , collar  125  is connected to and extends down from a lower surface of the lid  100  and is spaced radially inside of an outer perimeter of the lid  100 . The collar  125  is positioned concentrically between the vent tube  70  and canister  80  when viewed from a top plan view. In this embodiment, the collar  125  extends downwardly from the lid  100  to a height along the vent  60  at which upper edges of the vent tube  70  and canister  80  are provided. In another embodiment, the collar  125  extends relatively further down, between the vent tube  70  and canister  80 , and thus into the annular passage  78 . Regardless of how far the collar  125  extends from the lid  100  in any particular embodiment, the collar  125  is positioned with respect to the nozzle  90  and the lid  100  so that some of the cleaning fluid that is delivered out of the nozzle  90  is deflected by the collar  125  into the annular passage  78 , preventing such cleaning fluid from exiting the vent  60 . The collar  125  thus cooperates with the upper end of vent tube  70  and the upper end of canister  80  to define a serpentine path between the interior of the vent tube  70  and the exterior of canister  80 , which allows passage of air into and out of vat  7  and also functions to ensure that cleaning fluid from nozzle  90  does not escape from vent  60  other than through collection chamber  85  at the lower end of annular passage  78 . 
     Various alternatives and embodiments are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention.