Abstract:
An assembly for connection to the drain of a cooking appliance which diverts low volume flow efficient from the drain is disclosed. The assembly includes a defining a main flow channel. An auxiliary exit port is connected to the pipe in such a way that the low volume flow will be diverted from the pipe into A hot water entry pipe port is also connected to the pipe and is en connection with a hot water source which provides a flow of hot water into the pipe. Additionally, a solenoid valve regulates the flow of hot water into the pipe.

Description:
This application is a continuation-in-part of application number 08/969,207 filed Nov. 13, 1997, now U.S. Pat. No. 6,019,894, the entire disclosure of which is hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to a drain assembly for a cooking appliance and, more particularly, to a drain assembly for diverting cooking effluent into a grease/water separator. 
     A combination oven uses both steam and radiant heat in the cooking process. Typically, these ovens use a steam kettle to generate steam for the cooking chamber. The steam kettle must be periodically flushed to remove any limes, scales, or precipitate from the steam kettle. The flush cycle completely purges the water in the kettle by means of an internal pump or line pressure arrangement. This flush sequence can propel twenty to twenty-five liters of water through the kettle and into the combination oven. The flush water exits a discharge port in the oven in a short (30 to 60 second) time frame. These ovens typically use a condensate discharge pipe with an outer diameter of 50 millimeters. Therefore, the entire pipe cross section must be available to allow for such a high volume of water to be discharged in that time. 
     However, during the cooking process, condensed steam and grease exit the cooking area of the oven through the same discharge port in the oven as the flush water flow. This flow of condensed steam and grease exits at a much lower flow rate. It typically has been directed through the same drain line with its eventual discharge into a sewage outlet. In many applications, the grease tends to solidify within the drain pipe. Once that blockage occurs, the large flow of flush water cannot escape the drain pipe at a proper rate of speed. This backup may cause water to pool in the bottom of the appliance or leak out of the appliance through areas other than the drain. This backup may also cause contamination of the cooking racks and/or the food products placed on the cooking racks. Thus, there is a need to ensure that the drain pipe remains clear from any grease or other residue. 
     Further, the clogging of the drain pipe by the condensate from the cooking appliance causes drainage problems with other appliances connected to the drain pipe. Thus, there is a need to separate components of the condensate flow which could cause an obstruction within the drain pipe. In that regard, there is a need to divert the condensate to a grease/water separator or other pollution control device so that those components can be separated from the condensate stream thereby allowing a flow that is predominantly water to be discharged into the building&#39;s drain system. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a drain assembly to be attached between the discharge port of a cooking appliance and the drain line for a building. The cooking appliance may be a combination oven. The drain assembly is designed so that low volume effluent will be diverted from the main flow channel of the assembly so that periodic high volume flows may flow unobstructed through the assembly. 
     Accordingly, one aspect of the invention is to provide an accumulator on a pipe. The pipe defines the main flow channel. The accumulator provides a path to which the low volume flow can be gravitationally diverted. The low volume flow will then be discharged through an exit port in the accumulator. 
     Another aspect of the invention is to reduce the likelihood that components of the low volume flow will obstruct the main flow channel. Thus, a heat source is located in proximity to the accumulator. The heat source is sufficient to melt any meltable components of that low volume flow, such as cooking grease. 
     The assembly of a first embodiment is typically cylindrical with an outer diameter of about 50 millimeters. The assembly is preferably made with  16  gauge bright finish stainless steel. 
     In an embodiment of the invention, the accumulator is attached to the pipe so that the accumulator spans across the lowest arc segment of the pipe. The accumulator may also be substantially cylindrical with its cross section having a diameter of about one inch. The accumulator preferably extends from the pipe for a depth of approximately 0.20 inches. 
     In order to ensure that all of the low volume flow is diverted, the accumulator of this embodiment is preferably has two extensions extending from its upper surface upward along opposite sides of the pipe. The width of the extensions may taper as they extend along the pipe. The exit port may be a circular hole with a diameter of about 0.75 inches centered in the lower end of the accumulator. 
     The second embodiment has a housing into which the main flow channel enters. The drain pipe discharges into the housing. Inside the housing, the lower periphery of the drain pipe is open and replaced with a strainer assembly. The drain pipe may also be terminated in the strainer assembly. The strainer assembly is typically U-shaped. The drain pipe begins again on a downstream end of the strainer assembly. The strainer conveyor assembly is perforated to allow liquid to be gravitationally diverted into the sump. The strainer assembly provides a sufficient bridge between the inlet and outlet to allow the passage of a high volume flow without substantial diversion of liquid into a sump located at the bottom of the housing. The strainer conveyor may be removable, with the provision of a handle. The sump has a suction line for transport of the diverted liquid to a grease-water separator. As with other embodiments, a heat source can be located near the strainer assembly in order to keep the perforations clear of congealed grease which could form an obstruction. In this embodiment, the heat source maintains the diverted liquid in a flowable state. Additionally, after removal of the grease, the diverted liquid can be returned into the housing to flow to the outlet. 
     The low volume flow may be conducted from accumulator into a grease/water separator such as a Big Dipper® oil/water separator marketed by Thermaco, Inc., of Asheboro, N.C. It may be preferable to conduct the low volume flow from the accumulator to the grease/water separator using a suction pump. 
     Understanding that the purpose of the assembly is to maintain the main flow channel free from obstruction, such as cooking grease, in another aspect the invention maintains a heat source within close proximity to the assembly. The heat source keeps the components of the low volume flow above their respective melting points thus preventing coagulation of solids within the main flow channel. 
     In a preferred embodiment, the heat is provided by hot water flowing into the assembly. The hot water enters the assembly through an entry port which is upstream of the auxiliary exit port. The flow of hot water may be regulated by a solenoid valve. The heat source may also be an electrical heater. 
     In the process of the invention, the cooking appliance is periodically purged with a high volume flow of water to clear residue. This flow of water is drained through a drain assembly connected to the cooking appliance. Between the purgings, effluent from the cooking appliance drains into the drain assembly and then, within the drain assembly, is diverted from the main flow path used by the high volume flow. 
     In a preferred embodiment of this process, tie drain assembly is heated. The heat will maintain the cooking effluent in a liquid state so that it will flow and not obstruct the main flow path of the drain assembly. The heat is preferably provided by flowing hot water into the drain assembly. The flow of hot water may be regulated by a solenoid valve, or other suitable means, before it is introduced into the drain assembly, 
     It is preferable to divert the cooking effluent into an accumulator attached to the drain assembly. Subsequently, the effluent may be conducted into a grease/water separator in order for the grease and water components of that effluent to be properly disposed of. The effluent can be conducted to such a grease/water separator by using a suction pump in connection with the accumulator. 
     It should be understood that the apparatus, and the associated process, can be used with cooking appliances other than combination ovens, such as rotisserie ovens and the like. 
     These and other aspects of the present invention will become apparent to those skilled in the art after reading the following description of the preferred embodiment when considered with the drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view illustrating a first embodiment of the drain assembly according to the present invention; 
     FIG. 2 is a bottom plan view of the drain assembly shown in FIG. 1; 
     FIG. 3 is a top plan view of the drain assembly shown in FIG. 1; and 
     FIG. 4 is a schematic representation of the drain assembly in a kitchen setting according to the invention. 
     FIG. 5 is a perspective exploded view illustrating a second embodiment of the drain assembly according to the invention with part of the housing  114  shown broken away to expose its contents; 
     FIG. 6 is a side sectional view of the drain assembly shown in FIG. 5; 
     FIG. 7 is a top plan view of the drain assembly shown in FIG. 5; and 
     FIG. 8 is an end sectional view of the drain assembly shown in FIG.  6 . 
     FIG. 9 is a schematic representation of the drain assembly in another kitchen setting according to the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     In the following description, like reference characters designate like or corresponding parts throughout the several views. Also in the following description, it is to be understood that such terms as “forward,” “rearward,” “left,” “right,” “upwardly,” “downwardly,” and the like are words of convenience and are not to be construed as limiting terms. 
     It will be understood that the illustrations are for the purpose of describing a preferred embodiment of the invention and are not intended to limit the invention thereto. 
     As best seen in FIG. 1, a drain assembly, generally designated number  10 , is shown constructed in accordance with the present invention. The drain assembly  10  is primarily constructed of a pipe  12  which defines a main flow channel  16 . The main flow channel has a diameter sufficient to accommodate periodic purgings of a cooking appliance. An accumulator  14  spans across the lowest arc segment of the pipe  12 . The accumulator  14  has a first extension  20  and a second extension  22  extending upward along opposite sides of the pipe  12  and tapering in width as each one extends upwardly. The extensions  20  and  22  are connected to the accumulator  14  and are designed to divert a low volume flow in the pipe  12  into the accumulator  14 . Thus the entire volume of the low volume flow is highly likely to be diverted to the accumulator  14  by the force of gravity since the accumulator  14  provides a drop off to a lower level along the lowest arc segment. The extensions  20  and  22  of the accumulator  14  may be made by outward embossment of the wall of pipe  12 . Alternatively, they may be preformed and attached, as by welding to cover a cut-out in the wall of pipe  12 . Other suitable fabrication techniques may also be used. 
     In a preferred embodiment of the invention, a heat source is located proximate to the drain assembly  10 . As can be seen in FIG. 1, a hot water entry port  24  is connected to the pipe  12 . The hot water entry port  24  is located on the pipe  12  in a manner so that hot water can flow into the pipe  12  to maintain the low volume flow in a liquid state and prevent components of the low volume flow from blocking the main flow channel  16  and the accumulator  14 . The hot water entry port  24  is preferably located generally upstream of, and generally above, the accumulator  14 . 
     As can be seen in FIG. 1, the pipe  12  generally has a cylindrical body, preferably constructed of  16 -gauge stainless steel. 
     As can be seen in FIG. 2, the accumulator  14  is generally cylindrical and has an exit port  26  located within it. 
     A schematic representation of a typical drain assembly in a kitchen setting can be seen in FIG.  4 . The cooking appliance  30  is connected via a discharge pipe  50  to the drain assembly  10 . The main flow path of the drain assembly  10  exits through a second discharge pipe  50  into the building drain  46 . A suction pump  40  is connected to the exit port  26  of the accumulator  14  in a path divergent from the main flow channel of the drain assembly  10 . The suction pump  40  pumps the effluent into a grease/water separator  42 . Grease components  44  can be separated and removed, while a flow of water and other components less grease can pass to the building drain  46 . Alternatively, the water can be returned to the line  50 ′, as in the scheme of FIG. 9, described below. A hot water source  34  (such as the building&#39;s hot water supply) is connected to the drain assembly  10  through a conduit  52 . The flow of hot water through the conduit  52  may be regulated by a solenoid valve  32 . Value  32  may be opened periodically by controls provided on the cooking appliance  30 , or separate controls. 
     In operation, the system begins when a cooking appliance  30  is activated to begin the cooking process. Typically, a combination oven utilizes a steam kettle that has a flush cycle in the beginning of that cooking process. Of course, the flush cycle could take place after the cooking cycle. The flush cycle completely changes the water in the steam kettle by means of an internal pump or line pressure arrangement. This flush sequence generates a high volume of water which is flushed through the cooking appliance and out the oven condensate discharge port into a discharge pipe  50  in a short time frame. This high volume flush flow usually requires the entire pipe cross section of the discharge pipe  50  be open to allow the expeditious flow out of the combination oven  30 . As can be seen in FIG. 4, this high volume flush flow will enter the drain assembly  10  and exit through second discharge pipe  50  without being diverted. The flush flow will enter the building drain  46  unimpeded. The flush flow is high volume, but only for a brief period of time. 
     During the cooking cycle, the cooking appliance  30  dispenses steam into its cooking cabinet (not shown) to cook the food. Any fats, grease, or other material drains to the bottom of the cooking cabinet with condensate from the steam. This makes a low volume effluent of condensate and cooking residue that exits the cooking appliance  30  through the discharge pipe  50  and enters the drain assembly  10 . This low volume flow is gravitationally diverted into the accumulator  14  in the drain assembly. This flow is then suctioned by a pump  40  into a grease/water separator  42 . The grease/water separator  42  separates the grease components  44  for proper handling, and allows the rest of the flow to be sent to the building drain  46 . As can be seen in FIG. 4, to prevent the drain assembly  10  from being blocked, a hot water source  34  is connected to the drain assembly  10  to allow for hot water to flow through a conduit  52  into the drain assembly and maintain the low volume flow in a liquid state. A valve  32  regulates the hot water flow and is typically activated at the same time that the cooking cycle is begun. 
     In a second embodiment as shown in FIG. 5, the drain assembly  110  surrounds a pipe  112  and the main flow channel  116 . The downstream end of the pipe is the second discharge pipe  150 ′. A housing  114  defines a reservoir or sump  160  underneath the main flow channel  116 . The housing has an access lid  192 . A strainer  165  replaces the bottom periphery of the pipe  112  within the confines of the housing  114 . In this embodiment, the strainer  165  is U-shaped and has a multiplicity of perforations  170 . In operation, a low volume flow in the main flow channel  116  will be diverted through the perforations and into the sump  160 . The perforations are shown as slots, but any size or shape permitting low volume flows to pass to the sump while diverting high volume flows to the outlet may be used. 
     FIG. 6 shows how the apparatus diverts the low volume flow. A low volume flow enters the main flow channel  116 . The strainer  165  allows the low volume flow to pass through perforations  165 . The low volume flow, indicated generally by direction  116 ′, is diverted into the sump  160 . Once the accumulated liquid is separated in a grease/water separator, the water components may be returned to the discharge line  150 ′ through return line  184 . Return line  184  enters the pipe  112  downstream of the strainer  165  and carries the returned liquid to the building drain. 
     FIG. 7 shows that the housing  114  can be provided with a suction line  180  to remove liquid from the sump  160 , and shows the hot water line  182 , and a return line  184 . 
     As seen in FIG. 8, the lid  192  and strainer  165  can be removable and may have a handle  190  provided to permit easy removal. This design permits easy servicing. Accumulated liquid in the sump  160  will be removed through an exit port  126 . A suction line  180  enters through the exit port  126  and extends into the reservoir  160  so as to be able to conduct the accumulated liquid. The suction line  180  may convey the accumulated liquid to a grease/water separator, not shown in FIG.  8 . The liquid in line  180  may be pumped by a pump like pump  140  to a grease/water separator  142  as shown in FIG.  9 . The water from the separator may be directed to the building drain as in FIG.  4 . 
     FIG. 9 is a schematic representation of the drain assembly  110  in a second kitchen setting. The cooking appliance  130  is connected via a discharge pipe  150  to the building drain  46 . A suction pump  140  is connected to the exit port  126  of the drain assembly  110  and pumps the effluent into a grease/water separator  142 . Grease components can be separated and removed, while a flow of water and other components less grease can be returned to the discharge pipe  150 ′ in a location downstream from the strainer  165 . A hot water source  134  is connected to the housing  110  through a conduit  152 . The flow of hot water-through the conduit  152  may be regulated by a solenoid valve  132 . Solenoid valve  132  may be opened periodically by controls provided on the cooking appliance  130 , or separate controls. 
     In operation, the system begins when a cooking appliance  130  is activated to begin the cooking process. Typically, a combination oven utilizes a steam kettle that has a flush cycle in the beginning of that cooking process. Of course, the flush cycle could take place after the cooking cycle. The flush sequence generates a high volume of water which is flushed to the cooking appliance and out a discharge port into a discharge pipe  150  in a short time frame. This high volume flush flow usually requires entire pipe cross section of the discharge pipe  150  to be open to allow flow out of the cooking appliance  130 . As can be seen in FIG. 9, this high volume flush flow will enter the housing  110  and exit through second discharge pipe  150 ′ without being substantially diverted. This flush flow will enter the building drain  46  unimpeded. 
     During the cooking cycle, the cooking appliance  130  dispenses steam into its cooking cabinet (not shown). Any fats, grease, or other materials drain to the bottom of the cooking cabinet with condensate from the steam. This makes a low volume effluent of condensate and cooking residue that exits the cooking appliance  130  through the discharge pipe  150  and enters the housing  110 . This low volume flow is gravitationally diverted into the sump  160  through the perforations  170  of the strainer  165 . This flow may then be suctioned by a pump  140  into a grease/water separator  42 . The grease/water separator  42  separates the grease components  44  for proper handling, and allows the rest of the flow to be sent back to the downstream side of the strainer  165  where it enters the discharge pipe  150 ′ eventually to be sent to the building drain  46 . To prevent the strainer  165  from being blocked, a hot water source  134  is connected to the housing  110  to allow for hot water to flow through a conduit  152  into the strainer  165  and maintain the low volume flow in a liquid state in the sump  160 . A valve  132  may regulate the hot water flow and is typically activated at the same time as the cooking cycle is begun. 
     Certain modifications and improvements will occur to those skilled in the art upon a reading of the foregoing description. It should be understood that all such modifications and improvements have been deleted herein for the sake of conciseness and readability but are properly within the scope of the following claims: