The present invention relates generally to deep-fat fryers and, more particularly, to a deep-fat fryer cooking oil filtration arrangement.
A typical deep-fat fryer will include a fryer vat containing a heating bath of cooking oil. The cooking oil is adapted to receive baskets of food products such that the food products will be immersed within and cooked by the heated cooking oil. Such fryers may also include a heat exchanger and a pump. The pump is responsible for continuously pumping the cooking oil from the fryer vat, through the heat exchanger and back into the fryer vat such that the cooking oil remains at a substantially constant temperature, thereby allowing the food products to be evenly and consistently cooked within the fryer vat. More recently, fryers have been manufactured with in vat fire tubes and associated burners, with combusted gases being passed therethrough to heat the oil, eliminating the need to constantly pump the oil from the vat through a heat exchanger.
To extend the useful life of the cooking oil, it is a common practice to filter the particulate food matter from the cooking oil to minimize the carbonization of such food matter within the cooking oil. Some conventional fryers utilize a batch filtration system, in which the cooking oil is drained from the fryer vat and then manually or mechanically filtered before returning the cleansed cooking oil back to the fryer vat. Other conventional fryers utilize a continuous filtration system, in which a continuous filter is placed within the fluid path of the cooking oil, so as to continuously filter the cooking oil as it is being recirculated between the fryer vat and the pump/heat exchanger.
Previously known batch filtration systems have included oil receiving filtration pans or tanks into which oil from the fryer vat is drained, with a filter assembly placed flat over an outlet port in the bottom of the tank. Such filter assemblies typically utilize a paper filter with a diatomaceous material, sometimes in combination with a screen. These assemblies require some structure atop the paper and filter assembly for holding it in place. Dealing with paper filters can be cumbersome and messy. Similarly, the structure used to hold filters in place can be difficult to handle. Other paperless filter assemblies have been used, with a coupling member separate from the filter assembly providing attachment. Again, such systems can be difficult to handle.
Another issue with prior art filtration systems includes difficulty in cleaning the filtration tank as necessary between filtering operations. Portable filtration tanks/systems on wheels have been used for movement between different fryer devices. Tanks or pans within drawers at the bottom of the fryer device have also been used, but their removability has been limited due to excessive weight, commonly the result of structures attached thereto such as pumps. Further, mating couplets which have been provided in the past. With drawer type units have been subject to heavy wear or even damage due to positive latch mechanisms which have been used to hold the drawer in a closed position, as well as due to exposure of seals when the drawer is in an open position.
Additionally, previously known filtration systems have not provided suitable mechanisms for emptying oil into separate containers. For example, one prior art system requires the use of a separate attachment which can be screwed in line with an oil drain path to divert oil away from the normal drain container and into a separate container.
In any deep fat fryer there may also be the problem of debris/particulate buildup in the fryer vat if the particulate does not drain out of the vat during a filtering operation. This has typically been addressed by a manual cleaning of the bottom of the vat which is a less than desirable technique.
Accordingly, it would be desirable to provide an improved fryer filtration arrangement.
In one aspect of the present invention, a filtration arrangement for a fryer includes a pan for receiving oil from a fryer vat, the pan including an outlet opening, the outlet opening defining a first coupler. A filter assembly includes an interior defined at least in part by an outer filter screen material, a second coupler connected to the filter assembly and defining a passage which extends from the exterior of the filter assembly into the interior. The first coupler and second coupler are sized and shaped for slidingly mating with each other. The first coupler is mated with the second coupler so that oil traveling out of the pan during a filtration operation travels from the pan, through the outer filter screen material, into the interior of the filter assembly, and out of the interior of the filter assembly through a flow path defined by at least one of the first and second couplers.
In another aspect of the invention, a filtration arrangement for a fryer includes a fryer vat and a pan for receiving oil drained from the fryer vat, with a filter assembly within the pan for filtering oil passing through the pan. An oil drain path leads from an outlet opening of the fryer vat to the pan, and an oil return path leads from the pan back to an inlet opening of the fryer vat. A lower portion-of the fryer vat is shaped to direct particulate matter which settles in the fryer vat into a substantially linear region along a bottom surface of the vat. The fryer vat inlet opening is positioned at one end of the substantially linear region and the fryer vat outlet opening being positioned at an opposite end of the substantially linear region for causing oil being circulated during a filtration operation to flow from the fryer vat inlet opening, along the substantially linear region and out the fryer vat outlet opening to push particulate matter lying in the substantially linear region toward and out of the fryer vat outlet opening for delivery to the pan.
Still another aspect of the invention provides a filtration arrangement for a fryer including a fryer vat and a pan for receiving oil drained from the fryer vat, with a filter assembly within the pan for filtering oil passing through the pan. An oil drain path leads from an outlet opening of the fryer vat to the pan, and an oil return path leads from the pan back to an inlet opening of the fryer vat. A latch-free drawer is movable between open and closed positions relative to a fryer frame, and the pan is positioned in the drawer. During a filtration operation oil is drawn out of the pan along the oil return path and delivered back to the fryer vat. The oil return path is defined in part by a return coupler connected to and extending from a portion of the pan. The return coupler is aligned for slidingly mating with a corresponding coupler on the fryer frame when the drawer is moved to a closed position. The oil is drawn out of the pan along the oil return path in a manner which creates a suction force for holding the return coupler of the pan to the corresponding coupler of the fryer frame so as to maintain the drawer in a closed position during a filtration operation.
Referring to drawing
A basket type screen 42 is removably positioned within the pan 34 for filtering out debris entering the pan 34 within oil which is drained from one of the fryer vats 12A and 12B. At the bottom of the pan 34 a filter assembly 45 is provided for filtering the oil. An oil return path from the pan 34 back to the fryer vat 12A, 12B is formed in part by a coupler 44 which is connected to and extends from a front sidewall of the pan 34. The illustrated coupler 44 extends rearwardly back toward the fryer frame 20. A corresponding coupler 46 (
In the illustrated fryer 10, each vat 16A, 16B includes an associated exhaust stack 200A, 200B formed at the back of the fryer for venting combustion gases produced by the oil heating system which includes in vat fire tubes as will be described in more detail below with reference to
Referring now to
Near the top of front wall 56 a wall penetrating coupling assembly 58 passes through the wall 56, with piping 60 extending upward from the pan 34 and rearwardly as shown. The end of piping 60 acts as the return coupler 44 and is shown in cross-section in FIG. 3. The return coupler 44 mates with corresponding coupler 46 which is shown in cross-section in FIG. 4. In the illustrated embodiment the return coupler 44 comprises a male coupler with a chamfer 62 at its end, and the corresponding coupler 46 comprises a female coupler which includes a chamfered opening 64 to facilitate sliding engagement with return coupler 44. The internal surface of coupler 46 includes two annular recesses 66 for receiving sealing members such as o-rings 67 which engage the outer surface of the return coupler 44 in a friction fit manner when the coupler 44 is inserted therewithin. The internal o-rings 67 thus remain unexposed and protected from damage when the drawer 32 is opened and the return coupler 44 is removed from coupler 46.
One embodiment of a filter assembly 45 is shown in
The subject commercially available filter is modified by connecting a coupler 92 having a flow passage 94 therethrough to the opening 88 on the underside 76, such as by welding to the flange 90. The passage 94 leads from the exterior of the filter assembly 45 to its interior 82. An L-shaped handle member 112 is connected to the opening and flange at the upperside 74 of the filter assembly 45 to seal off the upperside opening. The handle facilitates manual installation and removal of the filter assembly. The handle member 112 may be welded or otherwise connected to the upperside 74 of the filter assembly 45.
The coupler 92 is sized and shaped for mating with a coupler 96 which is defined by opening 48 in the bottom wall 50 of the pan 34. In the illustrated embodiment, the coupler 96 is formed in member 52 which may be welded or otherwise connected to the exterior surface of the bottom wall 50. The entry to coupler 96 may be chamfered at 102 to facilitate coupler 92 being slidingly inserted therein. Coupler 92 may include an annular recess 104 which receives a sealing member such as an o-ring 105 for engaging an inner surface of coupler 96. A friction fit, quick connect/disconnect arrangement is thereby provided. It is recognized that the o-ring could be located internally along the wall of coupler 96. In one embodiment the coupler 92 has a cylindrical outer shape and has an outer diameter D between about 0.720″ and about 0.750″, a length L between about 0.4″ and about 0.6″, and a through diameter d between about 0.350″ and 0.400″, with a preferred outer diameter of about 0.735″, a preferred length of about 0.5″, and a preferred through diameter of about 0.350″. While the illustrated embodiment shows coupler 92 as a male coupler and coupler 96 as a female coupler, it is recognized that in other embodiments the coupler associated with filter assembly 45 could comprise a female coupler and that a male coupler could extend from the bottom wall 50 of the pan. Passage 106 is provided for leading to and coupling with piping 54 shown in FIG. 2.
Referring again to
In one embodiment, when the couplers 92 and 96 are fully coupled at least part of the underside 76 of the filter assembly 45 is spaced from the bottom wall 50 of the pan 34 to enable oil to flow through both the upperside 74 and underside 76 of the filter assembly 45 as it is drawn out of the pan 34. This arrangement provides a greater oil filtering surface area as compared to systems in which the filter material, such as paper media, lies flat against the bottom wall 50 of the pan 34. Positioning pegs or posts may be provided on the bottom wall 50 of the pan 34 for such purpose, or could likewise extend from the underside 76 of the filter assembly 45. Channels could also be formed in the bottom wall 50 of the pan 34.
Referring now to drawing
The oil return path from the pan 34 is formed in part by piping 54 and 60, return coupler 44 and corresponding coupler 46. Piping 134 leads from the coupler 46 to the pump 110. The outlet side of the pump 110 connects to piping 136 which extends to common piping 138. Common piping 138 includes segment 138A which, relative to the front view
By way of example, to filter the oil in vat 12B, the flow control device 130B is opened to permit oil to drain into the pan 34. The flow control device 142B is also opened to permit oil to be delivered back to the vat 12B. The pump 110 is then operated an oil is cycled from the pan 34, through the filter assembly 45, back along the oil return path through the pump 10 and to the vat 12B. During such operation the flow control devices 130A (not shown) and 142A are maintained in closed positions to prevent oil from draining from vat 12A and to prevent oil from being returned to vat 12A. When sufficient filtering has been achieved, the flow control device 130B is closed so that the vat 12B fills as oil is returned thereto by the pump 110. At the conclusion of the filtration operation the flow control device 142B is closed and the pump 110 is turned off.
Notably, a lower portion of each fryer vat 12A, 12B is shaped to direct particulate matter which settles in the fryer vat into a substantially linear region 150A, 150B along a bottom surface of the vat. In the illustrated embodiment this substantially linear settling is achieved using inclined bottom walls as best seen in the front view of FIG. 9. Each fryer vat inlet opening 140A, 140B is positioned at one end of the substantially linear region and each fryer vat outlet opening 120A, 120B is positioned at an opposite end of the substantially linear region for causing oil being circulated during a filtering operation to flow from the fryer vat inlet opening 140A, 140B, along the substantially linear region 150A, 150B, and out the fryer vat outlet opening 120A, 120B to push particulate matter lying in the substantially linear region toward and out of the fryer vat outlet opening 120A, 120B for delivery to the pan 34. In the illustrated embodiment, as best shown in
Also connected to common piping 138 is an oil dump path defined by piping 160. The piping 160 extends to a forward portion of the fryer frame 20 and includes a quick-disconnect coupling 162 at its end to facilitate connection of a hose which can be used to empty oil from the pan 34 into a separate container. A flow control device 164 is positioned along the oil dump path for controlling the flow of oil therealong. The flow control device 64 may, for example, be a manually operable valve including a handle 166 for operation by a user. In the illustrated embodiment, an oil dump is achieved by opening the flow control device 130A, 130B associated with the drain path of the vat to be dumped. The oil drains into the pan 34. The flow control device 164 is then opened and flow control devices 142A and 142B are maintained closed. When the pump 110 is operated, oil will be delivered to the piping 160 and out of the quick-disconnect coupling 162 when a hose is connected thereto.
Also shown in
Referring to
As illustrated, the pan 34 includes curved corners (e.g., corners 302, 304 of
Although the invention has been described and illustrated in detail it is to be clearly understood that the same is intended by way of illustration and example only and is not intended to be taken by way of limitation. For example, while a fryer including two vats has been shown in the illustrated embodiment, fryers including more or less vats could incorporate the subject filtration arrangement. Further, while the illustrated filter assembly is generally rectangular and envelope shaped, other filter assembly shapes could be used. While the filter assembly connects to the bottom wall of the pan, the outlet opening of the pan, and thus connection of the filter assembly, could also be on one of the front, back or side walls. Still further, while the illustrated coupling arrangement between the filter assembly and pan is formed by slidingly cooperating couplers, in some cases threaded couplers might be used, in which case the filter assembly handle could be used to rotate the filter assembly to achieve the desired threaded connection.
Accordingly, the spirit and scope of the invention are to be limited only by the terms of the appended claims.
This application is a continuation of application Ser. No. 09/760,356, filed Jan. 12, 2001 now U.S. Pat. No. 6,572,764.
Number | Name | Date | Kind |
---|---|---|---|
445223 | Knight | Jan 1891 | A |
2359368 | Klopfenstein | Oct 1944 | A |
2424211 | Webb | Jul 1947 | A |
2578129 | Daugherty | Dec 1951 | A |
2610740 | Hunter | Sep 1952 | A |
2635527 | Overbeck et al. | Apr 1953 | A |
2760641 | Mies, Jr. et al. | Aug 1956 | A |
2914063 | Wagner | Nov 1959 | A |
3045827 | Hough | Jul 1962 | A |
3147220 | Avery | Sep 1964 | A |
3159095 | Wagner | Dec 1964 | A |
3263818 | Gedrich | Aug 1966 | A |
3279605 | Shepherd | Oct 1966 | A |
3410199 | Quednau | Nov 1968 | A |
3477361 | Bradshaw | Nov 1969 | A |
3483981 | Gordon | Dec 1969 | A |
3608472 | Pelster et al. | Sep 1971 | A |
3667374 | Holmes | Jun 1972 | A |
3685433 | Cunningham | Aug 1972 | A |
3701313 | Boggs | Oct 1972 | A |
3735871 | Bisko | May 1973 | A |
3797378 | Morris | Mar 1974 | A |
3894482 | Murphy | Jul 1975 | A |
3973481 | Mies | Aug 1976 | A |
4084492 | Sullivan | Apr 1978 | A |
4113623 | Koether et al. | Sep 1978 | A |
4328097 | Whaley et al. | May 1982 | A |
4487691 | Panora | Dec 1984 | A |
4591434 | Prudhomme | May 1986 | A |
4604203 | Kyle | Aug 1986 | A |
4607857 | LeSage et al. | Aug 1986 | A |
4623544 | Highnote | Nov 1986 | A |
4747944 | George | May 1988 | A |
4805525 | Bivens | Feb 1989 | A |
4890548 | Grob et al. | Jan 1990 | A |
4895137 | Jones et al. | Jan 1990 | A |
4899649 | Grob et al. | Feb 1990 | A |
4945893 | Manchester | Aug 1990 | A |
4974501 | Grob et al. | Dec 1990 | A |
4994181 | Mullaney, Jr. | Feb 1991 | A |
5247876 | Wilson et al. | Sep 1993 | A |
5253566 | McCabe et al. | Oct 1993 | A |
RE34636 | Bivens | Jun 1994 | E |
5404799 | Bivens | Apr 1995 | A |
5449469 | Burklund et al. | Sep 1995 | A |
5486370 | Bivens | Jan 1996 | A |
5577438 | Amitrano et al. | Nov 1996 | A |
5582093 | Amitrano et al. | Dec 1996 | A |
5595107 | Bivens | Jan 1997 | A |
5597601 | Griffin | Jan 1997 | A |
5680811 | Highnote et al. | Oct 1997 | A |
5709899 | Bivens | Jan 1998 | A |
5731024 | Bivens | Mar 1998 | A |
5743175 | Crain et al. | Apr 1998 | A |
5870945 | Bivens | Feb 1999 | A |
6235210 | Saksena | May 2001 | B1 |
6306294 | Blair | Oct 2001 | B1 |
6378420 | Savage et al. | Apr 2002 | B1 |
6470794 | Takahashi | Oct 2002 | B2 |
6572764 | Mullaney, Jr. | Jun 2003 | B2 |
Number | Date | Country |
---|---|---|
2746728 | Apr 1979 | DE |
0649622 | Apr 1995 | EP |
Number | Date | Country | |
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20030196940 A1 | Oct 2003 | US |
Number | Date | Country | |
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Parent | 09760356 | Jan 2001 | US |
Child | 10421098 | US |