Abstract:
A filter mounting system of a filter assembly for a fryer apparatus is disclosed, the filter mounting system including a slip fitting slidably receivable in a slip fitting receiver of a tank outlet port. A grasping member is functionally attached to the mounting system for removal of the filter assembly without the necessity of cooling the cooking oil contained in the fryer.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of provisional application No. 60/391,056 entitled, “Fryer Filter Slip Mount And Method of Use,” filed Jun. 21, 2002 in the United States Patent and Trademark Office. 

   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not Applicable. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to frying apparatuses for deep-fat frying. More particularly, the present invention relates to a deep-fat fryer filter mounting apparatus, which permits removal of the filter assembly while the oil is hot. 
   2. Description of the Related Art 
   Cooking oil is extensively used in the food industry to cook various comestibles. Animal fat or other suitable material may sometimes be used as the cooking material in lieu of cooking oil. The term “cooking oil” is used herein to designate any such material. 
   Frying is frequently accomplished in relatively deep containers with the comestible to be cooked immersed in the cooking oil. In cases where quantities of food are regularly cooked in such a manner, the cooking oil becomes contaminated with various particles of food or other impurities, and charred food particles produce an odor, which adversely affects the taste of foods cooked therein. 
   Existing commercially available systems and apparatus for filtering cooking oil require that the cooking operation be interrupted to filter the cooking oil or to clean continuous filtering systems. A disadvantage of presently practiced methods of filtering cooking oil is that such methods require that the cooking operation be ceased during the period that the cooking oil is filtered. This results in significant downtime. Even with continuous filtering systems there is periodic delay for cleaning of the filters, which require the cooking oil to be cooled or drained. 
   U.S. Pat. No. Re. 34,636, reissued on Jun. 14, 1994, to the present inventor, describes a cooking oil filtering apparatus, which can be used to effectively remove particulates from the cooking oil. Such particulates may include coatings from fried objects, seasonings and the like. The cooking oil is drawn through wire mesh screens by applying suction at the filter interior. As the cooking oil is drawn to the wire mesh screens, the screen serves to remove particulates from the cooking oil. The particulate-free cooking oil is then drawn into an outlet and drawn through the tank to a pump. The pump passes the cooking oil back into the tank. This process is carried on until particulate matter is removed from the cooking oil. A filter powder may be dispersed in the cooking oil to accumulate on the outer surfaces of the wire mesh screens. The subject apparatus eliminated the need for filter paper. 
   U.S. Pat. No. 5,404,799, issued on Apr. 11, 1995, and U.S. Pat. No. 5,486,370, issued on Jan. 23, 1996, both to the present inventor, describe a cooking oil filtering apparatus and method which can be used to effectively remove particulates from the cooking oil. Though relatively infrequent, the apparatus and method require periodic shut-downs for cleaning operations. 
   The patent references and references contained therein neither teach nor disclose a filter mounting system for a continuous-filtering fryer of the present invention. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention is a filter mounting system for a continuous-filtering fryer of the type that includes a filter disposed in the fryer container, an outlet port connected to the filter, a container inlet and a pump for circulation of cooking oil through the filter, the outlet port and back into the container through a container inlet. The filter mounting system comprises a filter assembly that is releasably attached to the outlet port by a slip connect that may be readily and safely removed from the fryer without cooling of the cooking oil. A grasping member may be engaged by an adapted rod to remove the filter assembly from the tank while the cooking oil is hot. 
   The filter assembly may be assembled to maintain a variety of attitudes within the tank. The outlet port is in fluid communication with the interior of the tank so as to draw the cooking oil through mesh screens of the filter assembly. The filter assembly includes a lower cap member. The lower cap member is attached to a slip fitting, designed to slidably engage a receiving member of the outlet port. The lower cap serves to support the filter assembly relative to the outlet port and the tank. The lower cap member and slip fitting have an annular interior extending therethrough in fluid communication with the outlet port. The filter assembly also includes an upper cap member, which is threadedly received by the lower cap member. The upper cap has a head, a grasping member and a body portion. 
   Accordingly, the objects of my invention is to provide, inter alia, a slip mounting apparatus that:
         provides a stable mount for a fryer filter assembly;   provides a short filter cleaning period; and   provides for cleaning a fryer filter system without cooling the cooking oil.       

   Other objects of my invention will become evident throughout the reading of this application. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a partially cutaway isometric view of a continuous-filtering fryer employing a filtering mounting apparatus of the present invention. 
       FIG. 2  is a partial cross-sectional side view of the apparatus in the fryer of  FIG. 1  taken across line  2 — 2 . 
       FIG. 3  is a detailed cross-sectional and partially cutaway view of a horizontal filter assembly of the apparatus of  FIG. 1 . 
       FIG. 4  is an exploded view of the horizontal filter assembly of  FIG. 1 . 
       FIG. 5A  is a partial cross-sectional side view of the apparatus mounted in a  FIG. 2 , with the heating element raised for filter cleaning. 
       FIG. 5B  is a partial cross-sectional side view of the apparatus mounted in a  FIG. 2 , with the heating element in place for heating cooking oil. 
       FIG. 6  is a side view of an alternate vertical filter assembly of the present invention, with the front half cut away. 
       FIG. 7  is an exploded view of an alternate embodiment of the slip connect of the present invention. 
       FIG. 8  is an exploded view of an alternate embodiment of the slip connect of the present invention. 
   

   DESCRIPTION OF THE INVENTION 
   Referring to  FIG. 1 , there is shown at  10  a continuous-filtering fryer apparatus for use with the preferred embodiment of the filter assembly  11 , shown in  FIG. 2 , of the present invention. The continuous-filtering fryer apparatus  10  comprises tank  12 , inlet ports  14  and  16 , and outlet port  18 , pump  20  and filter assembly  11 . Each of these elements are arranged so as to provide the necessary filtering of the cooking oil (not shown) contained within the fryer apparatus  10 . 
   The tank  12  is suitable for receiving cooking oil therein. Tank  12  includes a bottom  24  and side walls  26 ,  28 ,  30 , and  32 . The side walls  26 ,  28 ,  30 , and  32  extend upwardly from the bottom  24 . The walls are arranged so as to define tank  12  for the containing of cooking oil therein. Suitable heating elements  33  are provided above screen  35  within the tank  12  so as to bring the cooking oil to a proper temperature. The heating elements  33  and the screen  35  are positioned above filter assembly  11  in tank  12 . Heating elements  33  extend across the interior of tank  12 . Segments of the heating elements  33  are shown in  FIG. 1 . 
   Referring to  FIGS. 1 and 2 , inlet ports  14  and  16  are affixed to side walls  32  and  28 , respectively. Typically, inlet ports  14  and  16  are positioned below the level of the cooking oil within tank  12 . Inlet ports  14  and  16  communicate with the interior of tank  12 . Return line  38  is connected to port  14 , so as to allow cooking oil to be passed through port  14  into the interior of tank  12 . Return line  36  is connected to port  16  to allow delivery of cooking oil through port  16  into the interior of tank  12 . A single return line  36  or  38  and a single inlet port  14  or  16  may be used. 
   The outlet port  18  is affixed to the tank  12 , so as to be in communication with an interior of tank  12  generally adjacent to bottom  24  of tank  12 . Outlet port  18  is connected by line  40  to pump  20 . Outlet port  18  and pump  20  are designed so as to produce a suction, which draws the cooking oil through the filter  22  of the filter assembly  11 . The cooking oil is drawn through line  40  into pump  20 . Pump  20  pumps the cooking oil through line  66  to return lines  38  and  36  leading to inlet ports  14  and  16 , respectively. 
     FIGS. 2 ,  3  and  4  show the configuration of filter assembly  11  as attached to outlet port  18 . Outlet port  18  extends through the bottom  24  of tank  12  and is sealed about its periphery to tank  12 . Outlet port  18  includes an interior passageway which allows for the movement of cooking oil therethrough. 
   Slip fitting receiver  19  extends upward from outlet port  18 . Slip fitting receiver  19  includes interior formed surface  44 . Outlet port  18  may include threaded portion  46  extending below bottom surface  24  for removable attachment to line  40  or may be fixedly attached to line  40 . 
   A slip fitting assembly  56  provides fluid communication between filter  22  and outlet port  18 . Slip fitting assembly  56  includes slip fitting  51  for connection with outlet port  18 . Slip fitting  51  and interior surface  44  are so formed that slip fitting  51  is readily slidably received in slip fitting receiver  19  and readily removed from slip fitting receiver  19 . 
   Slip fitting assembly  56  includes a lower cap  48  and an upper cap  52 . Lower cap  48  has internally threaded passageway  100 . One end of a slip fitting  51  is threadedly connected internally to one end of lower cap  48 . The other end  58  of slip fitting  51  slidably seats into slip fitting receiver  19 . Lower cap  48  extends upwardly and includes a generally flat top lip  50 . 
   A shoulder  17  is provided on slip fitting  51 . Upon installation of slip fitting  51  into receiver  19  shoulder  17  of slip fitting assembly  56  rests on upper end  15  during operation of pump  20 . Top lip  50  supports the filter  22  in a generally parallel relationship to bottom surface  24  of tank  12 . Accordingly, slip fitting assembly  56  is supported in an upright position in slip fitting receiver  19 . 
   Slip fitting  51  and interior surface  44  are structured such that they fit closely while allowing sliding movement. In addition, slip fitting  51  length  61  is greater than slip fitting  51  width  63 . The combination of the relatively close fit of slip fitting  51  and interior surface  44  and the greater length  61  versus width  63  provide stable support of filter assembly  56 . 
   In preferred embodiment, slip fitting  51  is cylindrical and interior surface  44  comprises the interior surface of a hollow cylinder. 
   Upper cap  52  includes grasping member  53 , bolt head  54 , and externally threaded upper cap body  104 . Upper cap  52  is threadedly connected internally of lower cap  48 . Filter  22  is sandwiched between upper cap  52  and lower cap  48 . In exemplary filter assembly  11 , filter  22  is comprised of multiple layers of washers, filter material and flow directing materials as well as mesh screens  114  and  116 . Upper cap body  104  has a plurality of radial ports  110 , which extend through the interior of upper cap  52 , so as to allow for suction forces interior of filter  22 , between the outside filter layers of upper mesh screen  114  and a lower mesh screen  116 . 
   Grasping member  53  extends upwardly from the bolt head  54 . In the preferred embodiment, grasping member  53  describes a loop structure. 
   A heat resistant rod  71  is configured with hook  73  to engage the grasping member member  53  on filter assembly  11  and distal handle  75 . Rod  71  is of sufficient length to allow a user to engage grasping member  53  by hook  73  with handle  75  positioned above tank  12 . Hook  73  is structured to allow the user to engage and release member  53  so that filter assembly  11  may be lifted from tank  12 . As the lifting is done by means of the remotely positioned handle  75 , it is not necessary to cool the cooking oil in the tank  12  prior to removal of the filter assembly  11 . 
   Heat resistant rod  71  may be provided with extension  77  extending from rod  71  toward hook  73 . Extension  77  defines hook well  72 . 
   Threaded body portion  104  has interior passageway  108 . Interior passageway  108  is in fluid communication with the interior passageway of outlet port  18 . Interior passageway  108  is drilled and tapped through body portion  104  so as to be in fluid communication with radial ports  110 . In this manner, filter  22  allows the flow of oil through filter assembly  11 , while trapping cooking particulates. 
   Upper cap  52  is threadedly fastened to lower cap  48 , so as to allow for simple removal and disassembly of filter  22 , as needed. Exemplary filter  22  is a generally flat member, which extends near bottom surface  24  within tank  12 . In use, the cooking oil will flow around all sides of filter  22 . 
   Referring to  FIGS. 2 ,  3 , and  4 , outlet port  18  has threaded portion  46 , which is threadedly connected to elbow  60  below bottom surface  24  of tank  12 . Elbow  60  connects to line  40 . Line  40  extends below the bottom surface  24  to inlet port  62  of pump  20 . When pump  20  is activated, a suction force is created through line  40  and filter  22 . In effect, this causes cooking oil contained within the interior of tank  12  to flow through filter  22 . Mesh screens  114  and  116  will cause the particulate matter within the cooking oil to accumulate on the surfaces. The filtered cooking oil flows through line  40  to pump  20 . 
   Pump  20  includes pump outlet port  64  connected to line  66 . Pump  20  causes the filtered cooking oil to pass through pump outlet port  64  and into line  66  in a continuous fashion. Line  66  will pass the cooking oil toward return lines  38  and  36 , as connected to inlet ports  14  and  16  on side walls of tank  12 . The arrows of  FIG. 2  show the flow of cooking oil during the operation of the present invention. 
   It is a feature of the exemplary fryer that pump  20 , when activated, exerts a negative pressure through outlet port  18  thereby drawing cooking oil through filter  22 . Such negative pressure further secures slip fitting  51  within interior surface  44 . Preferably, pump  20  is not activated when filter assembly  11  is being removed from receiver  19 . 
   Referring to  FIGS. 1 ,  5 A and  5 B, electrical heating elements  33  are positioned over screen  35  and attached to side wall  28  with hinges  31 . Heating elements  33  have a lowered position in which heating elements  33  are relatively parallel to bottom  24  and completely submerged in cooking oil. In raised position, heating elements  33  are rotated upward at hinge  31  to the point where heating element  33  no longer obstructs access to filter assembly  11 . In raised position, heating element may extend out of the cooking oil. 
   In an alternate embodiment, filter assembly  11  may have varied filter configurations. Referring to  FIG. 6 , the exemplary embodiment has two filters  22  and  22 ′ positioned vertically and parallel. Filters  22  and  22 ′ are mounted each to an end of T-cap  55 . On top of T-cap  55  is grasping member  53 . Opposite member  53 , T-cap  55  threadedly attaches to lower cap  148 . Lower cap  148  attaches to slip fitting  51 , opposite T-cap  55 . The filter assembly  11  of such alternative embodiment is adapted for insertion in relatively narrow and deep segments of tank  12  as are found in gas fryers. 
   Outlet port base  18 A is housed in bottom  24  in a manner similar to outlet port  18  in  FIG. 3 . Outlet port base  18 A threadedly receives outlet port extension  18 B, which extends outlet port receiver  18 C away from bottom  24 , so that filters  22  and  22 ′ do not touch bottom  24 . Outlet port receiver  18 C is shaped inside to form slip fitting receiver  19 , which slidably joins to slip fitting  51 . 
   Referring to  FIG. 7 , alternate embodiment slip fitting  51 A is structured in relation to insert receiver  19 A to allow slidable connection to alternate embodiment outlet port  218 C. Slip fitting  51 A is internally threaded similarly to lower cap  48  and is coupled to lower cap  48  with externally threaded connector  51 B. 
   Outlet port base  218 A is housed in bottom  24  in a manner similar to outlet port  18 A in  FIG. 6 . Outlet port base  218 A threadedly receives outlet port extension  218 B, which extends insert receiver  19 A away from bottom  24 . 
   Insert receiver  19 A has interior formed surface  244 , shaped to receive slip fitting  51 A so that slip fitting receiver  19 A provides stable support to slip fitting  51 A and the attached filter assembly  11 . 
   With slip fitting  51 A seated in slip fitting receiver  19 A, fitting shoulder  256  abuts against upper end  158  of insert receiver  19 A. Filter assembly  11  is accordingly supported on insert receiver  19 A and held in fixed position by the fit of slip fitting  51 A in receiver  19 A. 
   Referring to  FIG. 8 , an alternate embodiment slip fitting  51 B is depicted. In the alternate embodiment, slip fitting  51 B has a tapered contour. Outlet port receiver (not shown) has a corresponding inner taper to match the taper of slip fitting  51 B. 
   Referring to  FIGS. 2 and 3 , in operation, upon activation of pump  20 , the cooking oil is drawn by suction applied by pump  20  through filter assembly  11 , into the interior passageway of outlet port  18 , and through line  40  to pump  20 . 
   The vacuum gauge  41  monitors the vacuum of line  40  between filter assembly  11  and pump  20 . Increased vacuum at vacuum gauge  41  indicates a build-up of filter cake  118  and other particulate matter (such as coating or seasoning from items being fried) on filter assembly  11 . 
   Referring to  FIGS. 4 and 5A , upper cap  52  includes head  54  and grasping member  53  such that a heat resistant rod  71 , with a suitable hook  73 , may engage member  53  in order to extract filter assembly  11  while the cooking oil is hot. 
   When the build-up of filter cake  118  on filter assembly  11  reaches a point where filter  22  needs to be cleaned, the entire filter assembly may be removed without cooling the cooking oil. In one exemplary embodiment, heating elements  33  are electric and must be turned off prior to being rotated out of the oil. Once heating elements  33  are raised, allowing access to filter assembly  11 , a heat resistant rod  71 , configured with hook  73  to engage the grasping member member  53  on filter assembly  11 , is extended into the cooking oil. Hook  73  is engaged with member  53  and upward force is applied to filter assembly  11  from rod  71 . Once sufficient force is applied, slip fitting receiver  19  releases slip fitting  51 , and filter assembly  11  may be lifted from the cooking oil and removed from tank  12  to be cleaned. A clean replacement filter assembly  11  may be installed while the original filter assembly  11  is being cleaned, or the original filter assembly may be immediately cleaned and replaced. 
   To reinstall filter assembly  11 , filter assembly  11  is grasped by member  53  with hook  73  on rod  71 . Rod  71  is manipulated to place filter assembly  11  into tank  12  and submerge filter assembly  11  into the cooking oil. The operator uses rod  71  to position slip fitting  51  into slip fitting receiver  19  in outlet port  18 . The operator then pushes down on rod  71 , engaging hook well  72  onto member  53 , which applies pressure to slip fitting  51 , seating slip fitting  51  in slip fitting receiver  19 . Hook well  72  is not necessary in all cases. Pushing down on upper cap  52  with the end of rod  71  or hook  73  may apply sufficient force to engage slip fitting  51  into slip fitting receiver  19 . Once a clean filter assembly  11  is installed normal operation of fryer  10  may resume. 
   Referring to  FIG. 6 , an embodiment for a gas-heated fryer includes gas heating elements  133  and  133 ′ that do not obstruct access to filter assembly  111  from the top. In this embodiment, filter assembly  111  may be removed while heating elements  133  and  133 ′ are engaged. As with filter assembly  11  in  FIG. 5A , filter assembly  111  is removed and reinstalled by the use of rod  71 , with hook  73  and hook well  72 . Once a clean filter assembly  111  is installed, normal operation of fryer  10  may resume. 
   The foregoing disclosure and description of the invention is illustrative and explanatory thereof. Various changes in the details of the illustrated construction may be made within the scope of the appended claims without departing from the spirit of the invention. The present invention should only be limited by the following claims and their legal equivalents.