Abstract:
A device for filtering the frying bath of an electric fryer having a heating resistor that is immersed in a frying bath in a tank during frying, the device including: a filter screen adapted to extend beneath the immersed electric resistor; and at least one holding element for connecting said screen to the immersed electric resistor. An electric fryer composed of; a tank provided to receive a frying bath; an electric heating resistor provided to be immersed in the frying bath; and the device described above.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to the technical field of electric fryers and concerns more particularly electric fryers having an immersed electric heating resistor. The invention relates more specifically to filtration of the frying medium of such an electric fryer. 
   In fryers of the type mentioned above, heating of the frying medium is effected by an electric heating resistor immersed in the frying bath. The heating resistor is generally removable from the tank that contains the frying bath. 
   U.S. Pat. No. 6,363,834 describes an electric fryer having an immersed heating resistor on which a filter screen is disposed. 
   This arrangement permits recovery of cooking residues on the filter screen. These residues can then be withdrawn from the frying bath along with the immersed resistor carrying the filter screen. 
   This form of construction presents, however, the drawback of promoting carbonization of the cooking residues. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention provides a device for filtering the frying bath of an electric fryer having an immersed resistor in a particularly simple manner. Furthermore, the present invention provides a device that limits degradation of the frying bath of such an electric fryer. 
   More specifically, the present invention provides a device for filtering the frying bath of an electric fryer, the device being composed of a filter screen extending beneath an immersed electric resistor provided to be disposed in a tank containing the cooking bath, wherein the filter screen is connected to the immersed electric resistor by at least one holding, or retaining, element. This arrangement permits the filter screen to be placed in a cooler zone of the frying bath. Carbonization of residues collected on the filter screen can then be greatly reduced, or even completely prevented, which permits maintenance of a frying bath of better quality. The filtration operation is effectuated simply by withdrawing the immersed electric resistor from the frying bath. 
   Advantageously, the filter screen has a filtering wall mounted at a distance from the electric resistor. This arrangement permits direct heating of the filtering wall to be limited and thus contributes to reducing degradation of the residues. 
   Also advantageously, the filter screen is concave, thereby permitting improved retention of the residues during filtration. 
   Further advantageously, in order to facilitate cleaning, the filter screen is mounted to be removable from the electric resistor. 
   Also advantageously, the at least one holding element is secured to the filter screen and is detachable from the resistor. Alternatively, the holding element can extend from, or be fixed to, the electric resistor. 
   Also advantageously, the holding element has at least one retention zone associated with the electric resistor and at least one attachment zone associated with the filter screen. 
   Further advantageously, the retention zone is deformable, thereby permitting removal of the filter screen from the electric resistor. 
   According to a further advantage, the holding element has a connection, or linkage, zone between the retention zone and the attachment zone. This permits creation of a thermal break, or barrier, between the electric resistor and the filter screen. 
   According to a further advantage, the connection zone is deformable, thereby aiding separation of the filter screen from the electric resistor. 
   According to another advantage, in order to facilitate removal of the filter screen, the retention zone is prolonged by a handling zone. 
   Alternatively, the holding element is relatively rigid and the electric resistor can then be deformed slightly to be separated from one or more of the retention zones. 
   According to an advantageous form of construction, the holding element is fixed on a filtering wall of the filter screen. Preferably then, the holding element has a connection zone between the attachment zone and the retention zone. 
   According to another advantageous form of construction, the holding element is fixed on a peripheral edge of the filter screen. This holding element can also have a connection zone between the attachment zone and the holding zone. 
   The invention is additionally embodied in an electric fryer having a tank provided to receive a frying bath, an immerseable electric heating resistor provided to be disposed in the tank, and a filter screen, wherein the filter screen belongs to a filter device as described above. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded, perspective view of the components of an electric fryer equipped with an embodiment of the invention. 
       FIGS. 2–4  are perspective views showing three embodiments of a filter device and associated heating resistor according to the invention. 
       FIG. 3A  is a detail view of a component of the embodiment of  FIG. 3 . 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  shows an electric fryer having a housing  1  receiving a tank  2  intended to contain a frying bath such as a bath of oil or melted fat. An electric resistor  3  is arranged to be immersed in the bath in order to heat the frying medium. Electric resistor  3  emerges from a case  4  containing the controls for the fryer. A temperature sensor  5  is arranged between the legs of resistor  3  and is, for example, associated with a thermostat, which may be constructed to provide electronic regulation of the temperature of the frying medium. A frying basket  6  is provided to contain the food to be fried. A removable handle  7  is provided in order to facilitate removal of basket  6  from tank  2 . A lid  8  is provided to close tank  2  when the fryer is assembled for use, resistor  3  will be positioned below basket  6 . 
   The electric fryer further includes a filter screen  10  belonging to a filtration device for the frying bath. Screen  10  is attached to resistor  3  and extends below resistor  3 . Filter screen  10  has essentially a concave form, in order to better retain cooking residues coming from basket  6 . Filter screen  10  is arranged at a distance from resistor  3  in order to reduce heating of screen  10  and of the residues collected therein. 
   More particularly, as is shown more clearly in  FIG. 2 , electric resistor  3  has several parallel legs  3   a ,  3   b ,  3   c  and  3   d  connected together by curved parts. Two interior legs  3   b ,  3   c  are connected together at one of their ends and are connected at their other ends to respective ones of outer legs  3   a ,  3   d . Temperature sensor  5  is mounted between inner legs  3   b ,  3   c  by means of a transverse attachment piece  9 . 
   Screen  10  is connected to resistor  3  by two holding elements  11   a  and  11   b . Screen  10  is composed of a peripheral edge  12  and a filtering wall  13  that is surrounded by edge  12 . Cooking residues that drop from basket  6  are collected on filtering wall  13 . Filtering wall  13  has a concave form and extends below resistor  3 . Filtering wall  13  is, for example, constituted by a wire mesh that preferably has a mesh size smaller than that of basket  6 . The dimensions of filter screen  10  are selected to preferably leave a minimum space between screen  10  and the lateral walls of tank  2 . 
   Holding elements  11   a  and  11   b  each have a generally V-shaped form and the two upper ends of each of those elements form holding zones  14   a ,  14   b ,  15   a ,  15   b  for holding resistor  3 . Each of elements  11   a ,  11   b  has a center part that is lower than the holding zones and that forms an attachment zone  16   a ,  16   b  secured to filtering wall  13 . Connection, or linkage, zones  17   a ,  17   b  extend between each holding zone  14   a ,  14   b ,  15   a ,  15   b  and corresponding attachment zone  16   a ,  16   b . Holding elements  11   a  and  11   b  are formed, for example, by metallic tongues made of stainless steel soldered or brazed to filtering wall  13 . 
   When the user withdraws resistor  3  from tank  2  containing a cooking bath, filter screen  10  arranged under resistor  3  collects cooking residues such as for example scorched pieces that have fallen into the frying bath during previous withdrawal of basket  6  from tank  2 . Filter screen  10 , disposed at a distance from resistor  3 , permits collection of the cooking residue in a cooler zone of the frying bath, due particularly to the presence of connecting zones  17   a  and  17   b  and to the concave form of filtering wall  13 . Degradation of the cooking residues is thus slowed, which permits a better frying bath quality to be maintained. 
   Two alternative filter screens  20 , 30  removably assembled to resistor  3  are shown in  FIGS. 3 and 4 . The alternative embodiment shown in  FIG. 3  differs from that of  FIG. 2  in that filter screen  20  is more basin-shaped, has a peripheral edge  22  surrounding a filtering wall  23 , and is connected to resistor  3  by three holding elements  21   a ,  21   b  and  21   c.    
   Each holding element  21   a ,  21   b  and  21   c  has an attachment zone, shown at  26   a  for element  21   a  and at  26   c  for element  21   c . The attachment zone  26   b  for element  21   b  is shown in  FIG. 3A . Each attachment zone  26   b ,  26   c  is secured to filtering wall  23 . 
   Holding element  21   a  is arranged on the longitudinal axis of filter screen  20  and is formed by a U-shaped tongue whose lower part is attachment zone  26   a . The legs of the tongue are formed with respective concave formations that form holding zones  24   a  and  25   a . These holding zones grip outer lateral faces of inner legs  3   b  and  3   c , respectively, of resistor  3 . The free ends of the tongues form manipulating, or handling, zones  28   a  and  29   a  permitting the user to detach holding zones  24   a  and  25   a  from resistor  3 . The legs of the tongue also form connection zones  27   a ,  27   a ′ between holding zones  24   a ,  25   a  and attachment zone  26   a.    
   Holding elements  21   b  and  21   c  are arranged to one side and the other of the longitudinal axis of filter screen  20 , at a distance from holding element  21   a . According to one possible form of construction of holding elements  21   b  and  21   c , shown in  FIG. 3A , they may be made in one piece. Each holding element  21   b ,  21   c  includes tongues having branches extending from their attachment zone  26   b ,  26   c . The branches present an upper concave receptacle forming a retention zone  24   b ,  24   c . Each concave receptacle extends in total over more than 180° around the associated resistor leg to permit retention of filter screen  20  under resistor  3 . Retention zones  24   b  and  24   c  come to grip the lower sides of outer legs  3   a  and  3   d , respectively, of resistor  3 . The free end of each of the tongues forms a handling zone  28   b ,  28   c  permitting retention zones  24   b ,  24   c  to be detached from resistor  3 . The tongues have connection zones  27   b ,  27   c  between retention zones  24   b ,  24   c , on the one hand, and the corresponding attachment zones  26   b ,  26   c , on the other hand. 
   Holding elements  21   a ,  21   b ,  21   c  are deformable at the level of retention zones  24   a ,  25   a ,  24   b ,  24   c  and/or connection zones  27   a ,  27 ′ a ,  27   b ,  27   c  to permit the user to withdraw filter screen  10  from resistor  3 , for example for cleaning. 
   The alternative embodiment shown in  FIG. 4  differs from the examples shown in  FIGS. 2 and 3  in that filter screen  30  has a peripheral border, or rim,  32  surrounding a filtering wall  33  and connected to resistor  3  by a holding element  31  fixed to peripheral border  32 . 
   Holding element  31  is formed by a rod that is bent at several points and that is made, for example, of stainless steel. Holding element  31  has two parts that are symmetrical at one side and the other of the longitudinal axis of filter screen  30 . Holding element  31  is fixed to peripheral border  32  at attachment zones  36 , for example by soldering or brazing. Holding element  31  is composed of several inwardly extending protuberances spaced from the peripheral border. The inwardly extending protuberances form retention zones  34   a ,  34   b  on both sides of screen  30 . Retentions zones  34   a  hold outer legs  3   a ,  3   d  of resistor  3  from above, while retention zones  34   b  hold legs  3   a ,  3   d  of resistor  3  from below. Connection zones  37  are arranged between attachment zones  36  and retention zones  34   a ,  34   b . Resistor  3  is thus held at a distance from filtering wall  33  and from peripheral border  32 . 
   The elasticity of resistor  3  permits a lateral disengagement of outer legs  3   a ,  3   d  from the holding element. 
   According to a complementary variant, retention zones  34   a ,  34   b  can be formed by several separate holding elements  31 . 
   According to another complementary variant, other geometries can be envisioned for resistor  3  and for holding elements  11   a ,  11   b ;  21   a ,  21   b ,  21   c ; and  31 . 
   According to a further complementary variant, holding elements  11   a ,  11   b ;  21   a ,  21   b ,  21   c ; and  31  are not necessarily all fixed only to the filtering wall or only to the peripheral border of the filter screen. 
   According to yet another complementary variant, at least one deformable holding element can form a unit with filter screen  10 , displacement of resistor  3  permitting disengagement of the other holding element or elements from the filter screen. 
   According to still another complementary variant, filtering wall  13 ,  23 , or  33  is not necessarily formed by a mesh, but instead can be formed by a perforated sheet. 
   According to yet a further complementary variant, the holding elements could form a unit with resistor  3  in order to cooperate with filter screen  10 ,  20 , or  30 . 
   According to yet another complementary variant of the invention, tank  2  can have at least one retention means provided to suspend the filter screen in a raised position above the frying bath, to permit draining. The retention means is for example a hook or a lug forming part of a lateral interior face of the tank. The retention means can cooperate with the filter screen and/or with the resistor. The retention means is preferably disposed at the side opposite to the case containing control elements for the resistor. 
   The filtration device for a frying bath according to the invention can be formed by a filter screen provided to be mounted below an immersed electric resistor. The filtration device then forms an accessory that can be associated with the immersed electric resistor. 
   The filtration device for a frying bath according to the invention can equally comprise a filter screen and an immersed electric resistor, the filter screen being mounted in a manner that may or may not be removable below the immersed electric resistor. 
   This application relates to subject matter disclosed in French Application number FR 03 07415, filed on Jun. 19, 2003, the disclosure of which is incorporated herein by reference. 
   While the description above refers to particular embodiments of the present invention, it will be understood that many modifications may be made without departing from the spirit thereof. The accompanying claims are intended to cover such modifications as would fall within the true scope and spirit of the present invention. 
   The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims, rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.