VENT SYSTEM FOR COOKING APPLIANCE
A vent system for venting hot gas and effluents from a cooking appliance. The vent system includes a first direct vent structure having an inlet for receiving hot gas and effluents and an outlet communicating with atmosphere. The first direct vent structure defines a first flow path. At least one effluent-removal device is positioned in the first flow path for removing effluents from the hot gas. An atmospheric flue communicates with the outlet of the first direct vent structure for venting hot gas to atmosphere after it has passed through the effluent-removal device. A damper system and integrated control system are also disclosed.
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This application is a non-provisional of U.S. Provisional Patent Application Ser. No. 60/785,745, filed Mar. 24, 2006, the entirety of which is hereby incorporated by reference.
This invention relates generally to cooking systems, and more particularly to improved ventilation and energy management systems for cooking appliances such as cooking ovens (e.g., convection ovens, baking ovens and speed cooking ovens), rotisseries, broilers, solid fuel ovens, char broilers, and fryers.
Cooking appliances used in commercial establishments (e.g., institutions, and family, casual, fine-dining, and fast-food restaurants) generate heat, combustion gases, cooking gases, and effluents such as grease, moisture and other particulates. Large overhead exhaust hoods and associated fans are often used to vent such cooking appliances, but these systems require substantial air flow and are not energy efficient. Further, substantial amounts of heat typically escape from the cooking appliance, resulting in further energy loss. There is a need, therefore, for an improved ventilation and energy management system for cooking appliances, particularly in view of increasing utility costs and anticipated stricter environmental regulations requiring reduced levels of cooking by-products discharged to atmosphere.
SUMMARY OF THE INVENTIONAmong the several objectives of this invention may be noted the provision of an improved ventilation and energy management system for cooking appliances. In different embodiments, the system has one or more of the following advantages: flexibility and adaptability for integration with various types of cooking appliances; capture and disposition of hot gas and effluents in an energy efficient manner; adaptability to meet different effluent-removal requirements; integration of the system with the particulars of the cooking process, foods cooked and cooking appliance; reduced duct maintenance and cleaning requirements; an optional damper system for controlling flow through the system to increase effluent-removal efficiency and effectiveness, and to provide more efficient energy management; an optional integrated fan system for generating desired flow throughout the system; an optional recirculation system for re-circulating flow to improve effluent removal and energy management throughout the system and/or cooking appliance; an optional feature for controlling fans and/or other movable components of the vent system in response to sensing the presence or certain characteristics of the hot gas and effluents from the cooking appliance; and an optional embodiment where there is no need for exhausting hot gas to an atmospheric flue. It is anticipated that a system of this invention will contribute substantially to meeting the standards of an energy efficient or “green” restaurant, a goal which is becoming more and more important.
In general, a ventilation and energy management system of this invention has one or more unique features. In one embodiment, the system includes a direct exhaust vent adapted to be positioned adjacent the cooking appliance. The direct exhaust vent comprises a first direct vent structure having an inlet for receiving said hot gas and effluents and an outlet communicating with atmosphere. The first direct vent structure defines a first flow path from the inlet to the outlet for flow of hot gas and effluents along the flow path. At least one effluent-removal device is provided in the first flow path for removing effluents from the hot gas. The direct exhaust vent also includes an atmospheric flue communicating with the outlet of the first direct vent structure for venting hot gas to atmosphere after it has passed through the effluent-removal device.
In another embodiment, the vent system comprises an exhaust canopy for collecting hot gas and effluents from an environment surrounding the cooking appliance. The exhaust canopy has an exhaust duct and an exhaust fan for venting hot gas and effluents collected by the canopy. The system also includes a direct exhaust vent inside the exhaust canopy. The direct exhaust vent comprises a first direct vent structure defining a first flow path for directing hot gas and effluents exiting a cooking chamber of the cooking appliance, and an atmospheric flue communicating with the first flow path for venting hot gas to atmosphere.
In yet another embodiment, the vent system comprises an exhaust canopy for collecting hot gas and effluents from an environment surrounding a cooking appliance, and a direct exhaust vent inside the exhaust canopy. The direct exhaust vent has a first inlet for receiving hot gas and effluents exiting the cooking appliance, an outlet, and an atmospheric vent communicating with the outlet. The system also includes a fan box inside the exhaust canopy for directing hot gas collected by the exhaust canopy to a second inlet of the direct exhaust vent communicating with the atmospheric vent.
In another embodiment, the vent system is adapted for retrofit installation in an existing exhaust canopy for venting hot gas and effluents from a cooking appliance. The vent system comprises a housing adapted to be secured inside an existing exhaust canopy, and a direct exhaust vent inside the housing. The direct exhaust vent has a first inlet for receiving hot gas and effluents exiting an exhaust area of the cooking appliance, an outlet, and an atmospheric vent communicating with the outlet. The system also includes a fan box inside the housing for directing hot gas collected by the exhaust canopy to a second inlet of the direct exhaust vent communicating with the atmospheric vent.
In another embodiment, a vent system of this invention comprises a first direct vent structure defining a first flow path for venting hot gas and effluents from a first exhaust area of the cooking appliance, and a second direct vent structure defining a second flow path for venting hot gas and effluents from a second exhaust area of the cooking appliance. At least one atmospheric flue communicates with the first and second flow paths.
Another embodiment of this invention is directed to a method of venting hot gas and effluents from a cooking appliance of the type having a cooking chamber, a first exhaust area for exhausting hot gas and effluents from the cooking chamber, and a second exhaust area through which hot gas and effluents are exhausted from the cooking appliance into an environment surrounding the cooking appliance. The method comprises venting hot gas and effluents from the first exhaust area into a first direct vent structure defining a first flow path, and venting hot gas and effluents from the second exhaust area into a second direct vent structure at least partially defining a second flow path. The method also includes the step of venting the hot gas flowing along the first and second flow paths into a common atmospheric flue.
In another embodiment, the present invention is directed to a damper system for adjusting flow from an exhaust outlet of a cooking appliance. The damper system comprises a damper housing adapted to be connected to the exhaust outlet and defining a flow path for exhaust from the exhaust outlet. A damper member is movable in the damper housing between an open position allowing flow along the flow path at a first flow rate and a closed position in which the damper member partially blocks the first flow path for flow at a second flow rate less than said first flow rate but greater than zero to allow venting of the cooking appliance while reducing heat loss from the cooking appliance.
The present invention is also directed to an integrated cooking and ventilation system. The system comprises a cooking appliance, and a vent system for venting hot gas and effluents from the cooking appliance. The vent system includes at least one movable venting component and at least one motor for moving the at least one venting component. An integrated control system is provided for controlling operation of the at least one motor and associated venting component as a function of the operation of the appliance.
In another embodiment, an integrated cooking and ventilation system of this invention comprises a cooking appliance, a vent system for venting hot gas and effluents from the cooking appliance, and an integrated control system for controlling operation of the vent system and the cooking appliance. The integrated control system is responsive to operation of the cooking appliance to vary flow characteristics of the vent system.
In another embodiment, the present invention is directed to a method of operating a cooking appliance and vent system for venting hot gas and effluents from the cooking appliance. The method comprises operating the cooking appliance, and varying the flow characteristics of the vent system as a function of the operation of the cooking appliance.
Other objectives, advantages and features of this invention will be in part apparent and in part pointed out hereinafter.
Corresponding reference number designate corresponding parts throughout the several views of the drawings.
DEFINITIONSAs used herein, the following terms have the meanings set forth below.
The term “atmospheric flue” means a flue without an air assist device.
The term “cooking appliance” means any apparatus which is used for cooking food and which emits hot gas and effluents during the cooking process. The appliance may have a single cooking chamber or multiple cooking chambers arrayed horizontally and/or vertically.
The term “hot gas” means heated air or other gas, including cooking gas and combustion gas.
The term “effluents” means particulate material entrained in the hot gas, including grease, moisture and other by-products of the cooking process.
The term “effluent-removal device” means one or more mechanisms for removing effluents from a gas, including catalysts, filters, precipitators, UV systems, or combinations thereof.
The term “exhaust area” means any area from which hot gas (either with or without effluents) exits the cooking appliance, including dedicated exhaust outlets, doors, other entrances and exits, apertures, or other openings in the cooking appliance.
The term “high-vent mode” means a time or portion of a cycle of operation of a cooking appliance when its venting requirements are relatively high, as during a cook segment of a cycle when large amounts of hot gas and effluents requiring ventilation are generated.
The term “low-vent mode” means a time or portion of a cycle of operation of a cooking appliance when venting its requirements are relatively low, as during a warm-up or stand-by segment of a cycle, or when the appliance is off. The venting requirements (e.g., flow rate through the vent) during a low-vent mode are less than the venting requirements during a “high-vent” mode.
The term “open” means either fully open or partially open.
The term “closed” means a position more closed than the “open” position.
The term “variable-speed” as used in connection with a device (e.g., fan or motor) means that the device can operate at two or more speeds when it is in operation.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTSReferring now to the drawings,
The cooking appliance 3 shown in
The direct exhaust vent 1 can be mounted in different ways. In
If desired, the direct exhaust vent of this invention can be used in combination with a larger exhaust hood or canopy.
In the embodiment of
Optionally, the stand 125 may include an air supply duct 141 having an inlet 143 for connection to an outside source of air for providing additional make-up air to the cooking appliance 3 and surrounding environment (see
In the embodiment of
Although the first direct vent structure 533 is illustrated in
In the embodiment of
In the embodiment shown in
A direct exhaust vent of this invention can include more than two direct vent structures if that is desired or necessary to meet the ventilation requirements of a particular cooking installation. For example, a third direct vent structure could be added to the direct exhaust vent 501 shown in
Depending on the type of food being cooked, the cooking appliance, and the ventilation requirements, the direct exhaust vent 501 may include an effluent-removal device. One type of such device is a catalyst. The use of one or more catalysts has advantages over a conventional grease filter system because a catalyst generally has lower flow requirements than a grease filter. That is, to operate effectively, most grease filters require high-velocity flow through the filter. In contrast, a catalyst is more efficient at lower flow velocities since the hot gas and effluents reside in the catalyst for a longer period of time for more effective treatment by the catalyst. As a result, the use of a catalyst system can result in substantial savings over a conventional grease filter system.
In the embodiment of
The flow rate requirement of the direct exhaust vent 501, including the first and second (and any other) direct vent structures 533, 537, will vary depending on the particular installation and associated venting requirements. By way of example but not limitation, when the cooking appliance 3 is operating in a high-vent mode, the flow requirements of the direct exhaust vent 501 may be in the range of 0 to 220 CFM, or in the range of 30 to 200 CFM, or in the range of 50 to 180 CFM, or in the range of 60 to 150 CFM, or in the range of 70 to 120 CFM. These flow rates are substantially lower than the flow rates required by conventional ventilation systems, such as the large exhaust hoods or canopies of traditional design which often have flow requirements in the range of 150 to 450 CFM per linear foot of canopy. The result is improved energy efficiency and reduced operational costs. The direct exhaust vent 501 will also increase the capture of extraneous hot gas and effluents from the exhaust areas of the cooking appliance. Quick capture of the hot gas and effluents at the source reduces heat radiated into the environment surrounding the cooking appliance.
The direct exhaust vent 501 may or may not require a small air assist fan (either induced or exhaust) for generating addition flow through the vent, as needed or desired. The need for such a fan will depend on the particular installation and flow requirements of the system. In general, however, the use of such a fan will tend to create more of a vacuum inside the cooking appliance to inhibit hot gas and effluents from exiting the cooking appliance except through intended exhaust outlets. The use of such a fan will also permit the use of a thicker or more flow-resistant effluent-removal device (e.g., catalyst). An air assist fan can be used and installed in different ways. One possible embodiment involves the use of an exhaust fan to pull air through a bypass duct branching off from the atmospheric flue 541 of the direct exhaust vent. In this embodiment, a damper is provided in the atmospheric flue at a location above the branch. When the fan is in operation, flow is induced up through the bypass duct to atmosphere. When the fan is no longer needed, the damper is opened for normal flow through the atmospheric vent to atmosphere. In any event, each cooking appliance will require a different direct exhaust vent configuration and control logic, depending on the food being cooked, the type of cooking appliance, its various modes of operation, and the vent requirements during such modes of operation. As an example, an atmospheric vent may be used in one mode of operation and powered exhaust may be used in a different mode of operation.
To use the direct exhaust vent 501, the exhaust area 5 of the cooking appliance 3 is positioned adjacent (e.g., directly below) the lower inlet end of the direct exhaust vent. To facilitate such placement, the second direct vent structure 537 may be provided with one or more openings extending up from the lower edge of the structure, to permit passage of any vertical structure (e.g., short exhaust flue) projecting above the top wall of the cooking appliance. Each opening has a closure (e.g., a hinged or sliding door) for closing the opening after the cooking appliance is moved to its proper position relative to the direct vent structure 501. The one or more openings also provide ready access to the first direct vent structure 533 when the cooking appliance is below the direct exhaust vent 501 in a position where access might otherwise be limited. After the cooking appliance has been moved into position, the lower part of the first direct vent structure is moved up or down or moved in some other manner (e.g., swung in a horizontal plane as permitted by a flexible member) as needed to place the structure in proper position relative to the exhaust area 5 of the cooking appliance. The ability to move the first direct vent structure relative to the cooking appliance facilitates removal of the cooking appliance 3 from the direct exhaust vent 1 for cleaning. However, it will be understood that the first direct vent structure could be non-movable. The flue 9 from the second exhaust area 7 of the cooking appliance 3 is also connected to the atmospheric flue 541. Alternatively, the flue 9 could be connected to the direct exhaust vent at other locations, such as to the second direct vent structure so that hot gas from the flue 9 enters the second flow path defined by the second direct vent structure.
Referring again to
The damper member 655 can be configured in different ways. For example, in one embodiment, the damper member 655 is pivotally mounted on a shaft 657 and, when closed, has an outline which is only slightly smaller than the outline of the flow path through the first direct vent structure 623. The damper member 655 is perforated at 659 to permit some flow when it is in its closed position, the volume of such flow depending on the size and number of perforations 659 in the damper member. Alternatively, the damper member may be formed as a solid (non-perforated) blade or baffle mounted on a shaft for rotation about an axis transversely offset from the longitudinal center of the damper member. In this latter embodiment, the damper member is configured such that when it is in its closed position, one edge of the damper member contacts or is immediately adjacent an inner surface of the first direct vent structure 623 and an opposite edge is spaced a larger distance from an inner surface of the first direct vent structure to allow a limited but still substantial volume of flow past the damper member. Other damper configurations are possible. For example, two or more damper members may be mounted side by side in the flow path for pivoting or horizontal sliding movement.
The damper member(s) 655 is preferably rotated or otherwise moved between its open and closed positions by at least one motor (not shown) connected to the shaft 657 by suitable linkage (also not shown). The damper motor is controlled to open and close the damper member(s) in an appropriate manner, preferably according to the operation of the cooking appliance 3 (e.g., whether it is operating in a low-vent mode or a high-vent mode). To provide a full range of flow control, the position of the damper member(s) may be adjustable to any number of positions between fully open and fully closed. A stepper motor or other suitable drive mechanism can be used for this purpose.
The use of the damper system 653 described above is optional, as noted previously. If a damper system is used, it is preferably mounted along the flow path to control flow through the first direct vent structure 623 communicating with the flue (atmospheric or non-atmospheric).
The damper system, if used, may be used in combination with an air assist device (e.g., induced or exhaust fan) to provide specific flow configurations through the vent system, depending on the type of cooking appliance used and/or the type of food being cooked and/or the level of effluents. For example, the air assist device can be used to provide additional flow through the second direct vent structure and/or associated ducts (e.g., flue 9 in
In the illustrated embodiment 1101, the first direct vent structure 1133 comprises an upper part 1133A and a non-extensible lower part 1133B. However, it will be understood that the lower part could be extensible as described in regard to previous embodiments. The lower part 1133B is sized somewhat larger than the exhaust outlet 5 of the cooking appliance 3. The second (outer) direct vent structure 1137 is a double-wall structure comprising inner and outer walls 1137A, 1137B which are spaced apart to receive insulating material 1161. A door 1163 is hinged to the front of the second direct vent structure 1137 adjacent the lower end of the structure. The door 1163 swings up to an open position to facilitate movement of the cooking appliance 3 to a position below the direct exhaust vent 1101 in which the exhaust outlet 5 of the appliance 3 is disposed directly below the first direct vent structure 1133. The door 1163 then swings down to a closed position. The door may move between its open and closed positions in other ways (e.g., by sliding).
The direct exhaust vent 1101 also includes two effluent-removal devices, namely, a lower device (e.g., a catalyst) 1167 positioned in the exhaust outlet 5 of the cooking appliance 3 where it is supported by one or more brackets 1169 or other supporting device, and an upper device (e.g., a catalyst) 1171 positioned above the upper (outlet) end of the first direct vent structure 1133 where it is supported by one or more brackets 1181 or other suitable supporting device affixed to the second direct vent structure 1137. An opening 1183 is provided in the second direct vent structure 1137 to facilitate installation and removal of the upper effluent-removal device 1171. When the upper device 1171 is in place, a plate 1187 affixed to the device closes the opening. Suitable fasteners are used to secure the plate 1187 and catalyst 1171 in place.
The direct exhaust vent of
In the embodiment of
As shown in
Although not specifically shown in the drawings, it will be understood that the catalyst 1167 could be located in the exhaust area of the cooking appliance 3 immediately upstream from (below) the damper housing 1195 rather than actually in the damper housing itself, so long as the damper, when closed, functions to reduce the escape of heat from the appliance and thus maintain the catalyst at an elevated temperature.
If desired, the electronic controls for the cooking appliance and ventilation system can be integrated to provide an integrated control and energy management system to achieve more efficient ventilation and improved energy management. In such an integrated control system, the control panel on the cooking appliance 3 or a separate control panel may provide all control functions for the relevant components of the ventilation system, including any supply and exhaust fans associated with the direct exhaust vent, any supply and exhaust fans associated with the exhaust canopy, if the latter is used, and any damper system. Thus, for example, when the cooking appliance is operating in a high-vent mode, one or more of any such fans are operated at a higher speed and the damper system, if used, is moved to an open position. When the cooking appliance is operating in a low-vent mode, one or more of any such fans are operated at a lower or reduced speed (including off), and the damper system, if used, is moved to a closed position. Thus, the controls for the cooking appliance may be used to provide for maximum efficiency and reduced air flow and heat loss.
An exemplary operational cycle for a cooking appliance is described below. In this embodiment, the cooking appliance is a broiler having upper and lower burners for cooking food in a cooking cavity or chamber. A direct exhaust vent as described above (e.g., as shown in
During the start-up segment, all burners (lower and upper) are turned on and the broiler cooking cavity is heated to a predetermined temperature T1 (e.g., 680 degrees F.). The damper of the vent system 1101 is in its closed position to conserve energy (i.e., to reduce heat loss.) If an exhaust fan is used, the fan is turned off. After the temperature in the cavity reaches T1, as sensed by a suitable temperature sensor, the idle segment starts.
During the idle cycle segment, the upper burners are on and the lower burner cycles to maintain the broiler cavity temperature at temperature T1. The appliance remains in the idle cycle until the appliance is used in a cook cycle or is turned off.
The cook segment is initiated by an operator actuating a suitable control, such as one of a series of pushbuttons, each of which may correspond to a particular cooking recipe for a particular food. During the cook cycle, all burners are initially on, the upper burners cycle based on time in the cook recipe, and the lower burner cycles off when the cavity temperature, as sensed by a suitable sensor, reaches a maximum cooking temperature T2 higher than T1 (e.g., 775 degrees F.). The damper is opened at or about the start of the cook cycle so that hot gas and effluents (e.g., smoke) produced by the cooking are vented. If an exhaust fan is used, the fan is turned on. The cook segment continues according to the programmed cooking recipe at a suitable temperature or temperatures for suitable time period or periods. At the end of the cooking recipe the damper closes to conserve energy and the appliance enters the idle cycle. If desired, an operator can initiate a second or next cook cycle following the end of the preceding cook cycle. However, to conserve energy, if a predetermined time interval (e.g., two minutes) elapses without initiation of another cook cycle, the standby segment of the operational cycle is initiated.
During the standby cycle segment, the upper burners are turned off and the lower burner cycles to maintain the broiler cavity at a predetermined temperature (e.g., T1). The damper is also moved to its closed position to conserve energy. If an exhaust fan is used, the fan is turned off. If food product is to be cooked, an appropriate control (e.g., pushbutton) is actuated to terminate the standby cycle and initiate the idle segment described above to prepare the broiler for cooking. At the end of the idle segment, a cook segment is started by actuating a suitable control, such as a pushbutton, corresponding to the particular food to be cooked, as described above.
To conserve additional energy, it may be desirable in some situations (e.g., where little or no smoke is generated during the initial phase of the cook cycle segment) to divide the cook segment of the cycle described above into two sub-segments, i.e., a first cook/pre-smoke sub-segment and a second cook/smoke sub-segment. During the first sub-segment, all burners are on, and the lower burner cycles off when cavity temperature reaches an appropriate maximum cooking temperature (e.g., T2). Food product in the broiler is cooking but is not producing smoke. During this sub-segment, the damper remains in a closed position to conserve energy. The cook/pre-smoke sub-segment continues for a predetermined (programmed) period of time, which may vary depending on the type of food being cooked, following which the cook/smoke sub-segment is initiated. During this sub-segment, the damper is opened to exhaust hot gas and effluents from the cooking appliance. If an exhaust fan is used, the fan is turned on. As during the previous cook/pre-cook sub-segment, all burners are on, and the lower burner cycles off when the cavity temperature reaches the desired maximum cooking temperature (e.g., T2).
The number and type of cycle segments and/or sub-segments in an operational cycle will vary from one cooking appliance to another. Further, successive operational cycles may vary from one cycle to the next. By way of example, a first cycle may include start-up, idle, cook, cook, and standby segments, and a second cycle may include start-up, idle and cook segments. The present invention contemplates all such variations. In general, the method contemplates the basic steps of operating the cooking appliance in a cycle having different cycle segments, and varying the flow characteristics of the vent system as a function of the cycle segment. The integrated control system controlling the vent system and the cooking appliance operates to vary the flow characteristics of the vent system (e.g., by opening or closing dampers and/or changing fan speed) to accommodate the venting requirements of the different cycle segments.
In general, a vent system of this invention may be broadly described as a system for venting a cooking appliance (e.g., 3) having a first exhaust area (e.g., 5) for exhausting hot gas and effluents from the cooking appliance. The cooking appliance may also have a second exhaust area (e.g., exhaust outlet 7, door 4, relief vents, or other apertures) other than the first exhaust area through which hot gas and effluents escape. The vent system generally includes a first direct vent structure (e.g., 533) defining a first flow path (e.g., 535) for venting substantially only hot gas and effluents from the first exhaust area (e.g., 5), and an optional second direct vent structure (e.g., 537) defining a second flow path (e.g., 539) for venting substantially only hot gas and effluents from the second exhaust area (e.g., 7). In one embodiment (e.g., the
A ventilation and energy management system of this invention may have one or more of the features described above, or any combination of such features. These features include a fully integrated control system for controlling the operation of the cooking appliance and ventilation system so that the ventilation requirements of the cooking appliance are met efficiently and in a way which conserves energy. The ventilation system of this invention can also be used with conventional hood canopies, either in an original installation or in a retrofit installation, to increase ventilation efficiency and to conserve energy. If necessary or desirable to meet the particular ventilation requirements of a cooking system, more than one direct exhaust vent of this invention can be used in parallel. In such a situation, the vents can exhaust through separate atmospheric flues, or through a common atmospheric flue. The ventilation system may also include an optional damper system for controlling flow from the cooking appliance to achieve energy savings. The damper system can be used in combination with a direct exhaust vent described herein, or it can be used separately on the cooking appliance.
A vent system having one or more of the features described above will provide one or more advantages, including but not limited to: flexibility and adaptability for integration with various types of cooking appliances; the capture and disposition of hot gas and effluents in an energy efficient manner; adaptability to meet different effluent-removal requirements; integration of the vent system with the particulars of the cooking process, foods cooked and cooking appliance; less maintenance and cleaning of the vent system components; and a substantial step toward meeting the standards of an energy efficient or “green” restaurant, a goal which is becoming more and more important.
When introducing elements of the present invention or the preferred embodiments(s) thereof, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.
As various changes could be made in the above constructions, products, and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
Claims
1. A vent system for venting hot gas and effluents from a cooking appliance, said vent system comprising
- a direct exhaust vent adapted to be positioned above the cooking appliance,
- said direct exhaust vent comprising a first direct vent structure having an inlet for receiving said hot gas and effluents and an outlet communicating with atmosphere,
- said first direct vent structure defining a first flow path from said inlet to said outlet for flow of said hot gas and effluents along the flow path,
- at least one effluent-removal device in said first flow path for removing effluents from said hot gas, and
- an atmospheric flue communicating with the outlet of the first direct vent structure for venting hot gas to atmosphere after it has passed through said effluent-removal device.
2. A system as set forth in claim 1 wherein said direct vent structure is movable so that it may be positioned adjacent an exhaust area of said cooking appliance.
3. A system as set forth in claim 2 wherein said direct vent structure has an upper section and a lower section movable up and down relative to the upper section to facilitate positioning adjacent said exhaust area of the cooking appliance.
4. A system as set forth in claim 1 wherein said direct exhaust vent further comprises a second direct vent structure having an inlet for receiving hot gas and effluents and an outlet communicating with said atmospheric flue, said second direct vent structure at least partially defining a second flow path for directing hot gas and effluents from the environment surrounding said cooking appliance to said outlet of the second direct vent structure.
5. A system as set forth in claim 4 further comprising a second effluent-removal device in said second flow path.
6. A system as set forth in claim 5 wherein said second direct vent structure surrounds said first direct vent structure and is spaced from the first direct vent structure to define said second flow path.
7. A system as set forth in claim 1 further comprising an exhaust canopy having an exhaust duct and a powered exhaust fan for collecting hot gas and effluents from an environment surrounding said cooking appliance, said direct exhaust vent being mounted inside said exhaust canopy.
8. A system as set forth in claim 1 further incorporating a damper system comprising a damper member movable in the first direct vent structure between an open position allowing flow along the first flow path at a first flow rate and a closed position allowing flow along the first flow path at a second flow rate less than the first flow rate but greater than zero to allow venting of the cooking appliance while also reducing heat loss from the cooking appliance.
9. A vent system for cooking appliance having a first exhaust area for exhausting cooking hot gas and effluents from the cooking appliance and a second exhaust area through which cooking hot gas and effluents escape the cooking appliance, said vent system comprising
- a first direct vent structure defining a first flow path for receiving hot gas and effluents from said first exhaust area,
- a second direct vent structure defining a second flow path for receiving hot gas and effluents from said second exhaust area, and
- at least one atmospheric flue communicating with said first and second flow paths.
10. A vent system as set forth in claim 9 wherein said second direct vent structure surrounds said first direct vent structure and combines with said first direct vent structure to define said second flow path.
11. A vent system as set forth in claim 9 wherein said first and second flow paths communicate with a single atmospheric flue.
12. A method of venting cooking gas and effluents from a cooking appliance of the type having a cooking chamber, a first exhaust area for exit of hot gas and effluents from the cooking chamber, and a second exhaust area for exit of hot gas and effluents from the cooking appliance into an environment surrounding the cooking appliance, said method comprising
- venting cooking gas from said first exhaust area into a first direct vent structure defining a first flow path,
- venting cooking gas from said second exhaust area into a second direct vent structure at least partially defining a second flow path, and
- venting said cooking gas flowing along said first and second flow paths into a common atmospheric flue.
13. A method as set forth in claim 12 further comprising catalyzing said hot gas and effluents as they flow along at least one of said first and second flow path.
14. A method as set forth in claim 12 further comprising catalyzing said hot gas and effluents as they flow along said first and second flow path.
15. A damper system for adjusting flow from an exhaust outlet of a cooking appliance, said damper system comprising
- a damper housing adapted to be connected to said exhaust outlet and defining a flow path for exhaust from said exhaust outlet, and
- a damper member movable in the damper housing between an open position allowing flow along the flow path at a first flow rate and a closed position in which the damper member partially blocks the first flow path for flow at a second flow rate less than said first flow rate to allow venting of the cooking appliance while reducing heat loss from the cooking appliance.
16. A damper system as set forth in claim 15 further comprising an effluent-removal device in said damper housing.
17. A damper system as set forth in claim 16 wherein said effluent-removal device is located upstream from said damper member.
18. A damper system as set forth in claim 16 wherein said damper member is perforated.
19. A damper system as set forth in claim 16 further comprising a damper motor for moving said damper member between said open and closed positions, and a control for operating said damper motor responsive to operation of said cooking appliance.
20. A damper system as set forth in claim 15 further comprising a catalyst in said damper housing upstream from said damper member whereby movement of the damper member to its closed position is adapted to reduce heat loss from the cooking appliance and catalyst.
21. An integrated cooking and ventilation system comprising
- a cooking appliance,
- a vent system for venting hot gas and effluents from said cooking appliance, said vent system comprising at least one movable venting component and at least one motor for moving the at least one venting component, and
- an integrated control system for controlling operation of said at least one motor and associated venting component as a function of the operation of the cooking appliance.
22. A system as set forth in claim 21 wherein said at least one movable venting component is a variable-speed fan driven by said at least one motor, said control system being operable to operate said fan at a first lower speed during a low-vent mode of the cooking appliance and at a second higher speed during a high-vent mode of the cooking appliance.
23. A system as set forth in claim 21 wherein said at least one movable venting component is a damper member movable by said at least one motor between open and closed positions, said control system being operable to move said damper member to its closed position when the cooking apparatus is operating in a low-vent mode and to its open position when the cooking apparatus is operating in a high-vent mode.
24. A system as set forth in claim 23 wherein said damper member in its said open position allows flow along a first flow path at a first flow rate through the vent system, and wherein said damper member in its said closed position only partially blocks the first flow path for flow at a second flow rate less than said first flow rate but greater than zero to allow venting of the cooking appliance while also reducing heat loss from the cooking appliance.
25. A system as set forth in claim 24 further comprising a catalyst in said first flow path upstream from said damper member whereby movement of the damper member to its closed position is adapted to reduce heat loss from the cooking appliance and catalyst.
26. An integrated cooking and ventilation system comprising
- a cooking appliance,
- a vent system for venting hot gas and effluents from said cooking appliance, and
- an integrated control system for controlling operation of said vent system and said cooking appliance,
- said integrated control system being responsive to operation of the cooking appliance to vary flow characteristics of the vent system.
27. An integrated cooking and ventilation system as set forth in claim 26 wherein said vent system comprises a damper member movable between an open position to allow the flow of hot gas and effluents from the cooking appliance along a flow path at a first flow rate and a closed position partially blocking the flow path for flow of hot gas and effluents from the cooking appliance at a second flow rate less than said first flow rate but greater than zero to allow venting of the cooking appliance while also reducing heat loss from the cooking appliance, said control system being operable to move said damper member to its closed position when the cooking apparatus is operating in a low-vent mode and to its open position when the cooking apparatus is operating in a high-vent mode.
28. An integrated cooking and ventilation system as set forth in claim 27 further comprising a catalyst in said flow path upstream from said damper member whereby movement of the damper member to its closed position is adapted to reduce heat loss from the cooking appliance and catalyst.
29. A method of operating a cooking appliance and vent system for venting hot gas and effluents from the cooking appliance, said method comprising
- operating the cooking appliance, and
- varying the flow characteristics of the vent system as a function of the operation of the cooking appliance.
30. A method as set forth in claim 29 further comprising operating the cooking appliance in a cycle having different cycle segments, and varying the flow through the vent system as a function of the cycle segments.
31. A method as set forth in claim 30 wherein said vent system comprising at least one movable venting component and at least one motor for moving the at least one venting component, said method further comprising controlling said at least one motor to move said at least one venting component to increase or decrease the flow through the vent system as a function of the cycle segment.
32. A method as set forth in claim 30 wherein said venting component is a damper.
33. A method as set forth in claim 30 wherein said venting component is a fan.
Type: Application
Filed: Mar 23, 2007
Publication Date: Sep 27, 2007
Applicant: DUKE MANUFACTURING CO. (St. Louis, MO)
Inventors: Lawrence W. Hake (Destin, FL), John J. Hake (Edwardsville, IL)
Application Number: 11/690,435
International Classification: F24C 15/20 (20060101);