Patent Application
20050224069
The invention relates generally to systems for moving, treating and venting air in a space and, more particularly, to ventilating systems, such as those used with cooktops and the like.
Various types of systems have been designed and are in use for venting and circulating air in environments such as kitchens. In general, ventilating and circulating systems serve to remove and recirculate, or to vent air from above or adjacent to a stove, cooktop or other device. The systems draw in air and vapors that may be laden with grease and odors, clean the air, and either recirculate the air to the room or vent the air to the outside. Because the vapors and hot air rise, the systems are typically situated above the cooking surface and associated with a hood, although other systems may be located adjacent to or even in the cooking system itself.
Such kitchen ventilating systems typically include, without limitation, fans, filters for grease removal and a control system. Typical kitchen ventilating systems are designed to cover the whole area of a cooking apparatus with at least one centrifugal fan and a set of filters for grease removal. However, in many cases a user of the cooking apparatus performs the cooking activities using only a limited number of burners among the available number of burners in the cooking apparatus. The kitchen ventilating systems covering the whole area of the cooking apparatus in such cases distribute the static pressure developed by the fan on the entire area of the cooking apparatus, thus requiring higher capacity fans for effective capture of the vapors over the cooking surface. Such conventional systems thus result in relatively high energy consumption and noise generation.
In a conventional kitchen ventilating apparatus limited flexibility is provided to the users in terms of setting the apparatus in exhaust or ventilation modes. Moreover, while certain systems permit some degree of regulation of the speed of the fan, at the fan can most often be set to only one of typically available two or three pre determined speed options. However, usage of these limited options may result in situations where insufficient or excess fan power is delivered, resulting in either poor capture of flumes or excess energy consumption and noise generated, respectively.
Accordingly, it would be desirable to develop a system that senses the active zone of a cooking apparatus and the target air constituents to be removed from the air. It would also be advantageous to provide a system that could utilize this information to operate the system in a most effective manner, while maintaining the flexibility to the user for operation of the system.
Briefly, in accordance with one aspect of the present invention a kitchen ventilation system includes a sensor for detecting a chemical composition over an active zone of a cooktop. The system also includes an air moving device for displacing air including the chemical composition and an air flow direction control device for directing air displaced by the air moving device between exhaust and recirculation flow paths. A control circuitry is coupled to the sensor, to the air moving device and to the air flow direction control device for regulating operation of the air moving device and a position of the air flow direction control device based upon signals from the sensor.
In accordance with another aspect of the present invention, a method for ventilating air over an active side of a cooktop comprises sensing a side of a cooktop on which cooking is performed and controlling an air moving device for displacing air from the cooktop and an air flow direction control device for directing air displaced by the air moving device between exhaust and recirculation flow paths based upon the sensed side of the cooktop.
These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Referring now to
The housing 12 and its housed components are shown disposed over a cooktop 28 for treating air adjacent to a cooktop 28 of a cooking appliance such as a gas stove, a gas oven and so forth. In general, vapors, odors, chemical compositions, and so forth will be created or originate from one of more active zones 30 of the cooktop 28, typically those over or with which cooking operations are performed. The sensor 14 is configured to receive inputs 32 regarding the characteristics of the air above and adjacent to an active zone 30 of the cooktop 28. It should be noted that, as used herein, the term “active zone” includes an area over the cooktop where the cooking fumes, vapors, smoke and combustion byproducts are generated as a result of cooking activities of a user of the cooking apparatus. Typically, the inputs 32 received by the sensor 14 includes a chemical composition 34 of the air above the active zone 30 of the cooktop 28.
Furthermore, the sensor 14 may be configured to capture temperature 36 and humidity 38 data of the air above and adjacent to the active zone 30 of the cooktop 28 as a part of the input 32. As discussed in greater detail below, such data is used by control circuitry 40 for regulating the operation of the air moving device 16 and a position of the air flow direction control device 18.
In one embodiment, the air moving device 16 receives signals related to certain operating parameters (e.g., speed of a fan) from the control circuitry 40, for generating required static pressure by the air moving device 16. In another embodiment, the air flow direction control device 18 receives signals from the control circuitry 40 and selects a position of the air flow control device 18 for directing air displaced by the air moving device 16 between exhaust and recirculation flow paths (e.g., positions of a louver or diverting gate).
Further, air purification device 20 may be used for air purification by reducing the concentration of certain chemical compositions 34 of the displaced air through the air moving device 16. The air purification device 20 according to this embodiment may include, but is not necessarily limited to, an active device, a corona discharge device and an ultraviolet air purification device. In another embodiment, the air purification device 20 may include a filter to facilitate odor destruction and microorganism destruction of the displaced air by the air moving device 16. Alternatively, a UV-based system with the UV source 26 may be used for the destruction of the odor generated from the cooktop 28 and for the removal of any microorganisms if present in the air above and adjacent to the cooktop 28. Moreover, a grease filter may be used to capture grease entrained in the combustion byproducts from the cooking apparatus.
In operation, the sensor 14 detects the active zone 30 of the cooking apparatus and the target air constituents to be removed from the air above the active zone 30 of the cooktop 28, and provides this information to the control circuitry 40. In addition, the sensor 14 may also be configured to detect the UV intensity of the UV based odor and microorganism reduction system. This information may be utilized by the control circuitry 40 for regulating the operation of the air moving device 16, the air flow direction control device 18 and the air purification device 20 to maintain the desired air quality.
Control circuitry 40 may include an interface 42 for facilitating interface between the kitchen ventilation system components, and a controller 44 powered by a power supply 48. The controller 44 may be hard-wired and housed in a suitable exposed or covered enclosure fixed on or even within the kitchen ventilating system housing. Alternatively, the controller 44 may be placed in a remote location. Further, the controller 44 may receive and transmit signals pertaining to the status of the air quality and corresponding control and display signals remotely via means such as, infrared, radio frequency and electromagnetic transmission signal transmission media. Additionally, the controller 44 may use the temperature 36 and humidity 38 data acquired over the cooktop 28 via sensor 14 to compute temperature and humidity-compensated response of the air quality sensor 14 to assess the change in air quality on account of elements other than temperature 36 and humidity 38.
In general, in a presently contemplated embodiment, the controller 44 offers a momentary high power operation for a pre-determined time during start-up, and later changes to an optimum power mode of operation based on air quality status. In addition, the controller 44 may have a set of predefined programs stored that can be individually executed by a user of the system.
In a present embodiment, the control circuitry 40 also includes memory circuitry 46 for storing the pre-defined programs, internal references 50 for the operation of the components of the system and so forth. The internal references 50 may include operating cycle set points 52, operating cycle timings 54, sensor look up tables 56 for the sensor 14, ventilation rate tables 58 for the air moving device 16, a timer 60, an internal counter 62, and so forth. These references and devices may be utilized by the controller 44 for deciding the operating parameters for the kitchen ventilating system 10. Further, these operating parameters are communicated as, or used to derive output signals 68 to the air moving device 16, the air flow direction control device 18, and the air purification device 20.
Such output signals, indicated collectively by reference numeral 68, are transmitted from the controller 44 to the air moving device 16, the air flow direction control device 18 and the air purification device 20 to regulate operation of the system. Such output signals may include, without limitation, air moving device speed 70, air moving device status 72, air flow direction control device status 74 and UV source status 76. The status of the above mentioned parameters may be made available to a user of the system via a display system 66 which will be discussed hereinafter. Also, the controller 44 is configured to receive user inputs 64 which may be used by the controller 44 for deciding the operating parameters for the kitchen ventilating system 10.
FIG.2 illustrates an exemplary display system 66 and user inputs 64 of a kitchen ventilation system of the type shown in
In the illustrated embodiment, the user inputs 64 typically includes operation state 88, air circulation mode selection 90, start or delay option 92, operating cycle selection 94, lamp control option 96, air quality sensitivity level option 98, counter reset option 100, and so forth. The operation state 88 may set the kitchen ventilation system 10 in either manual state or auto state. The air circulation mode 90 includes settings for placing the air flow direction control device 18 in exhaust or recirculation modes.
Further, the location of the forward side 106 of the cooktop 28 and the aft side 108 of the cooktop 28 may also affect the operating parameters of the kitchen ventilating system 10. For example, the forward side 106 of the cooktop 28 may be adjacent to a wall at the installation site. Alternatively, the forward side 106 of the cooktop 28 may be adjacent to an open space. Similarly, the aft side 108 of the cooktop 28 may be either adjacent to a wall or adjacent to an open space. In addition to the sensor 14, as described above, the air moving device 16 is also coupled to a sensor 114 for detecting the speed of the air moving device 16. Further, a sensor 116 is coupled to the air flow direction control device 18 to detect the status (e.g., position) of the air flow direction control device 18.
In the present embodiment, the controller 40 (see
In another embodiment, the air purification device 20 is configured to reduce the content of certain chemical compositions 34 of the air displaced by the air moving device 16. Exemplary air purification devices 20 include, without limitation, an active device, a corona device, a UV air purification device and so forth. Moreover, the air purification device 20 may have a filter to facilitate odor destruction and microorganism destruction of target air constituents or compositions as sensed by the sensor 14 above and adjacent to the active side 30 of the cooktop 28. As will be appreciated by those skilled in the art, the odor and microorganism destruction may also be achieved through suitable filters such as, activated carbon. Alternatively, other systems could be used, for example, a UV radiation system, catalytic oxidizer, ozone generator and so forth. As will be appreciated by those skilled in the art, the system may convert a part of the UV output from the UV based odor and microorganism destruction system into visible light by using a transparent object with suitable phosphor coating. This may be used for illuminating the cooking space simultaneously along with odor and microorganism destruction.
The present configuration of the ventilating system offers an extremely flexible platform for various types of logical operation of the system components based upon sensed, input and reference parameters of the types described above. For example,
As shown in step 126, the system calculates a ratio of the AQ parameter as sensed on a first side (AQ1) of the active zone 30 of the cooktop 28 and the second side (AQ2) of the active zone 30 of the cooktop 28. Further, at step 128, this ratio is compared with a first reference value of the ratio of the AQ parameters on the two sides. As shown at step 130, if the calculated ratio is greater than the first reference value, the system sets the airflow direction control device 18 for first side in exhaust mode and the sets the airflow direction control device 18 for second side in re-circulation mode or in off mode; if the calculated ratio is less than the first reference value, the system proceeds to the step 132.
Next, at step 132 the calculated ratio of the AQ parameter on the two sides is compared with a second reference value of the ratio of the AQ parameters on the two sides. At step 134, if the calculated ratio is less than second reference value, the system sets the airflow direction control device 18 for first side in re-circulation mode or off mode and the sets the airflow direction control device 18 for second side in exhaust mode. If the calculated ratio is greater than the second reference value, the system proceeds to the step 136. At step 136, the system sets the airflow direction control device 18 for first side in exhaust mode and the sets the airflow direction control device 18 for second side in exhaust mode with reference to the limits 138 defining the air circulation modes for the two sides of the air flow direction control device 18.
As another example, the present system configuration affords site-specific operation programming. As mentioned above, the various sides and zones of the cooktop may be positioned adjacent to walls, open areas, and so forth. Similarly, the cooktop may be provided at specific heights above the cooktop, and the cooktop and system housing may be of various sizes.
Following the selection of the operating configuration based on the input duct parameters, the characteristics of the system based on the installation parameters are identified in accordance with the exemplary step sequence 162. In general, the sequence begins at step 164 where the width of the hood is read by the system. At step 166 and step 168 the room dimensions to define the volume and the installation location are specified as input parameters respectively. Further, at step 170 and step 172 the inputs regarding the height of the system above the cooktop and the type of the fuel used for the cooking apparatus are specified respectively. Here again, such inputs may be provided manually at the time of setup or configuration of the system. At step 174 the operating parameters for the kitchen ventilation system 10 based on the installation site parameters may be decided. Here again, more or fewer of these exemplary factors may be considered for system configuration.
In the present embodiment illustrated in
Further, as discussed above, the controller 40 may have a set of internal references 50 to control and operate the various components of the kitchen ventilation system 10. The controller 40 may also receive inputs 64 from a user of the system for providing flexibility to the user for operating the system.
In the present embodiment, the power output 224 from the controller 44 may include, without limitation, power output for air moving device 226, power output for air flow direction control device 228, power output for excitation of sensors 230, power output for lamp 232 and power output for the UV system 234. Further, the signal output 68 transmitted from the controller 44 to the components of the kitchen ventilation system 10 may include air moving device speed 70, air moving device status 72, air flow direction control device status 74, UV source status and so forth.
As will be appreciated by those skilled in the art, the present system thus allows for closed loop control for managing air above a cooktop 28 based on assessing the status of air quality by monitoring the level of the target constituents present in the air. The system is typically installed and used near a cooking appliance such as, cooking range, oven, or grill for moving and treating cooking fumes, vapors, smoke and other combustion products resulting from the cooking activities of a user of the system. Further, the system as described in the various embodiments hereinabove, uses the response of the air quality sensors to generate suitable control and display signals to facilitate controlling various elements such as, without limitation, operating speed and status of the air moving device 14, opening or closing of the air flow direction control device 16, activation and control of odor removal system and so forth.
In addition, the system also provides flexibility to a user for deciding the operating parameters by specifying certain user-defined inputs. As noted above, the system operates at an operating point determined by the sensing and control system which includes parameters such as, operating speed, operating duration and so forth, thus reducing the acoustic noise of the system during operation. Similarly, the system provides a very flexible platform that may be specifically adapted to the configuration and aspects of the site in which the system is installed to provide optimum performance.
The various aspects of the methods described hereinabove have applications in other environments for managing air. The embodiments described hereinabove can be used in the heating, ventilating and air conditioning area for managing air and maintaining required air characteristics in a space for human occupancy. The techniques may also be employed in a variety of appliances for example, a refrigerator deodorizing system may be controlled using a sensor to detect food odors, a clothes washing machine may be controlled by sensing a target compound that may be an ingredient of the washing agent to evaluate the options for the operation of the washing machine and so forth.
While only certain features of the invention have been illustrated and described herein, many modifications and changes will occur to those skilled in the art. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the invention.
