Patent Publication Number: US-10782030-B2

Title: Cooktops with integrated hoods

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a national stage entry from International Application No. PCT/IB2017/051685, filed on Mar. 23, 2017, in the Receiving Office (“RO/IB”) of the International Bureau of the World Intellectual Property Organization (“WIPO”), and published as International Publication No. WO 2017/175085 A1 on Oct. 12, 2017; International Application No. PCT/IB2017/051685 claims priority from Italian Patent Application No. 102016000034820, filed on Apr. 5, 2016, in the Italian Patent and Trademark Office (“IPTO”), the entire contents of all of which are incorporated herein by reference. 
     TECHNICAL FIELD 
     The present disclosure relates to a cooktop in accordance with the preamble of claim  1 . 
     Particularly, but without limitation, the present disclosure relates to a cooktop integrating a hood that is commercially available under the name of “downdraft hood”. 
     BACKGROUND OF THE INVENTION 
     Domestic hoods have become a common feature in residential kitchens, due to their undisputed usefulness in extracting food preparation gases, i.e. vapors generated during by cooking. 
     The provision of domestic hoods that can effectively remove cooking vapors generated during food preparation is of increasing importance. 
     For this purpose, hoods have been developed that can both extract air and exhaust the extracted air out of the house, using an intake section, and filter such air and recirculate it into the domestic environment. 
     Downdraft hoods are among the variety of commercially available hoods, and are often integrated either in a cooktop or in a kitchen furniture countertop. 
     Namely, a downdraft hood is configured to generate a crossflow that is higher than the ascending flow rate of cooking steam, so that such steam is extracted toward the cooktop in a vertical downward direction. 
     One example of these downdraft hoods is disclosed in U.S. Pat. No. 2,674,991, US 2007/0062513 or WO 2012/146237. 
     These documents disclose a cooktop with a hood integrated therein. The hoods disclosed therein are configured to extract gases through a cavity or slot formed in the cooktop, substantially close to the geometric center defined by the food heating zones. 
     While the cooktop implementations as disclosed in U.S. Pat. No. 2,674,991, US 2007/0062513 and WO 2012/146237 afford adequate function for their intended purposes, they still have a poorly efficient construction, in terms of both power and, especially, fluid dynamic efficiency. 
     Therefore, the technical purpose of the present disclosure is to provide a cooktop with an integrated hood that is generally more efficient than prior art designs. 
     SUMMARY OF THE INVENTION 
     According to the present disclosure, the above mentioned technical purpose and objects are fulfilled by a cooktop as defined in one or more of the claims annexed hereto. 
     Advantages 
     Furthermore, the present disclosure provides a cooktop with an integrated hood that has an improved power efficiency, i.e. consumes less power than prior art designs. 
     The present disclosure also provides a cooktop with an integrated hood that has a more efficient filtering effect on the extracted gases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further features and advantages of the present disclosure will be more clearly apparent from the illustrative, non-limiting description of preferred, non-exclusive embodiments of a domestic hood as shown in the annexed drawings, in which: 
         FIG. 1  shows a perspective top view of one embodiment of a cooktop of the present disclosure; 
         FIG. 2  shows a perspective bottom view of the hood of  FIG. 1 ; 
         FIG. 3  is an exploded perspective view of the parts of the hood of  FIG. 1 ; 
         FIG. 4  shows a perspective sectional view of the hood of  FIG. 1 , with certain parts omitted to better show other parts; and 
         FIG. 5  shows a lateral sectional view of the hood of  FIG. 1 , with certain parts omitted to better show other parts. 
     
    
    
     DETAILED DESCRIPTION 
     Even when this is not expressly stated, the individual features as described with reference to the particular embodiments shall be intended as auxiliary to and/or interchangeable with other features described with reference to other exemplary embodiments. 
     A cooktop of the present disclosure has been generally designated by numeral  1  in the figures. 
     The cooktop  1  has predetermined width “L”, length “1” and height “H” and comprises, preferably within such height “H”, a device  2  that accommodates the parts required for controlling and heating/cooking food, as well as for extracting cooking vapors F, as described below in greater detail. 
     Such cooktop  1  defines a top surface  1 A and a bottom surface  1 B. 
     Namely, when the cooktop  1  is installed, the top surface  1 A is designed to be the exposed or visible side and the bottom surface  1 B is designed to be the side that is hidden to the view of users, e.g. embedded in kitchen furniture. 
     In one aspect, a plurality of cooking zones  3  and a cavity  4  can be found in the top surface  1 A. 
     The plurality of cooking zones  3  are conveniently arranged over the top surface  1 A and are particularly able to radiate heat to transfer such heat to a container in which the food to be heated is held. 
     In a preferred embodiment, the cooking zones  3  are embodied as resistive or, more preferably, inductive heating elements. 
     While the plurality of cooking zones  3  are four zones in the exemplary embodiment of  FIG. 1 , other embodiments might envisage a greater or smaller number of zones. 
     In one embodiment, the top surface  1 A is embodied as a glass sheet or a sheet made of any material having glass-like properties. 
     The cavity  4  substantially extends between the top surface  1 A and the bottom surface  1 B and is preferably located in a central area relative to the positions of the cooking zones  3 . 
     In the particular embodiment of the figures, the cavity  4  extends from the top surface  1 A and almost reaches the bottom surface  1 B without touching it, i.e. leaves a space that, as described in greater detail below, is designed for collection of water, steam and/or fluids. 
     Particularly, also as shown in  FIG. 1 , the cavity  4  forms an inlet port  4 A, preferably having a circular shape, which is protected by a grille  4 B, and a bottom  4 C (see  FIG. 5 ). 
     The cavity  4  has a cylindrical shape, which is open both on the lateral surface and on the base surface (i.e., the surface that forms the bottom  4 C) for the cooking vapors F to be able to flow toward the first and second cooking vapor intake chambers  6  and  8 , as described in greater detail below. 
     It shall be noted that the grille  4 B is both removable from the inlet port  4 A and has a safety purpose, as it prevents the introduction of elements that might interfere with the operation of the electric machine  12 . 
     In one aspect, also referring to  FIG. 5 , the cooktop  1  comprises a filter  11  arranged in the cavity  4  to filter out grease and vapors in cooking gases. 
     Namely, such filter  11  is designed to create a form-fit with the cavity  4 . 
     Preferably, the filter  11  is a grease filter consisting of metal mesh or other materials having similar characteristics. 
     In a preferred embodiment, the filter  11  has a cylindrical shape and can be pulled off the cavity  4  for the user to carry out normal maintenance operations, such as cleaning or replacement. 
     In one aspect, the device  2  forms a mounting unit with the cooktop  1 , for operating the cooktop and allowing cooking vapors F to flow downwards, i.e. below the top surface  1 A. 
     In other words, the device  2  is integrated with the top surface  1 A, such that the extraction hood is integrated in the cooktop. 
     Namely, this device  2  is configured to convey the flow of cooking vapors F that has been and is being generated above the cooking zones  3  in a vertical downward direction below the cooktop itself. 
     In a peculiar aspect of the present disclosure, also referring to  FIGS. 3 and 5 , the device  2  comprises in succession, from the top surface  1 A:
         an apparatus  5  operably configured to contain the heating elements required for heating the cooking zones  3  and the electronics for controlling the cooktop  1 ,   a first cooking vapor intake chamber  6  in fluid communication with such cavity  4 ,   a fan housing  7  for a radial fan  7 A, and   a second cooking vapor intake chamber  8  in fluid communication with such cavity  4 .       

     It shall be noted that, as used herein, the term “in succession” designates the succession of the aforementioned elements in the specified order, in the direction from the top surface  1 A toward the bottom surface  1 B. 
     Advantageously, the fan housing  7  is in fluid communication with both the first cooking vapor intake chamber  6  and the second cooking vapor intake chamber  8 . 
     In one aspect, the first cooking vapor intake chamber  6  is configured to divide the cooking vapors F into a first portion F 1  of the cooking vapors F, to be conveyed downwards into the fan housing  7 , and a second portion F 2 , to be conveyed upwards into the fan housing  7  through said second cooking vapor, intake chamber  8 . 
     Therefore, due to the presence of the first cooking vapor intake chamber  6 , the cooking vapors F are divided into first and second portions F 1  and F 2 , which are conveyed with a less turbulent flow, i.e. a more laminar flow, toward the fan housing  7 . 
     This separation of the cooking vapors F into the first and second portions F 1  and F 2  is particularly beneficial as compared with a single downward stream of cooking vapors flowing directed toward the fan housing  7 , as disclosed in the prior art, as the first and second portions F 1  and F 2  have less vorticity and are less exposed to pressure losses. 
     Namely, in the present disclosure the cooking vapors F are separated into the first and second portions F 1  and F 2  by a perimeter wall  6 A of the first cooking vapor intake chamber  6 . 
     Such perimeter wall  6 A acts as a conveyor of the cooking vapors F, and particularly acts as a partition for such cooking vapors F, which flow along the cavity  4  between the first and second cooking vapor intake chambers  6  and  8 . 
     Such perimeter wall  6 A particularly defines an outer surface, which faces the cavity  4 , and an inner surface, which faces the first and second cooking vapor intake chambers  6  and  8 , as well as the fan housing  7  for the radial fan  7 A. 
     Due to the profile of the outer surface of the perimeter wall  6 A, the cooking vapors F are divided into the first and second portions F 1 , F 2  respectively and, due to the profile of the inner surface of the perimeter wall  6 A, the first portion F 1  and the second portion F 2  are conveyed by laminar flow toward the fan housing  7 . 
     Particularly, the curved shape of the perimeter wall  6 A makes such first and second portions F 1  and F 2  more laminar as it facilitates and promotes their movement toward the fan housing  7 . 
     In a preferred embodiment, the curved shape of the perimeter wall  6 A has the shape of an arc of a parabola. 
     In one aspect, the first portion F 1  flows through an intake grille  6 B to access the first cooking vapor intake chamber  6  from the cavity to reach the fan housing  7  of the radial fan  7 A, whereas the second portion F 2  flows through an intake grill  7 E to access the fan housing  7  of the radial fan  7 A. 
     It shall be noted that the intake grilles  6 B and  7 E are the grilles required by regulations to protect user safety, by preventing users from directly reaching the radial fan  7 A and the electrically powered parts. 
     It shall be further noted that the intake grille  6 B not only acts as a protection element, but can also impart a more regular pattern to the first portion F 1 . 
     For this purpose, the intake grille  6 B is placed proximate to the bottom  5 A of the apparatus  5  housing the electronics. 
     Due to this position of the intake grille  6 B relative to the bottom  5 A of the apparatus  5 , the first portion will be directed outwards, i.e. substantially parallel to the top surface of the cooktop  1 , before reaching the fan housing  7 . 
     In order that the cooking vapors F may be drawn in through the cavity  4 , the cooktop  1  comprises an electric machine  12  which is configured to actuate the radial fan  7 A, for example, by a mechanical coupling between the rotor of the electric machine  12  and the hub of the radial fan  7 A. 
     For example, the electric machine  12  is embodied as a single electric motor. 
     Preferably, the cooktop  1  uses a single fan housing  7  (which is known to act as a volute for the first and second portions F 1  and F 2  and hence as a path for the gases toward the vapor vent pipe  9 ) having the radial fan  7 A therein. 
     In an alternative embodiment, two opposed fans may be provided in the fan housing  7 , which are both actuated by a single electric motor  12 . 
     In a preferred embodiment, the diameter of the radial fan  7 A is 185 mm and its rotation, imposed by the electric motor  12 , may be as high as 2,700-3,000 revolutions/min. 
     As shown in the table below, these dimensional characteristics, as well as the separation of the cooking vapors F into first and second portions F 1  and F 2 , will provide a better energy efficiency class and a higher fluid dynamic efficiency (FDE) index as compared with prior art cooktops. 
     In one aspect, also referring to  FIG. 5 , the electric machine  12  is at least partially accommodated in the first cooking vapor intake chamber  6 . 
     Namely, one portion of the electric machine  12  is accommodated in the first cooking vapor intake chamber  6  and the rest is accommodated in the fan housing  7 . 
     This is beneficial in that, as the motor is not entirely contained in the fan housing  7 , i.e. part of it is external to the volume defined by the fan housing  7 , there will be more space in the fan housing  7 , and a greater amount of air may be drawn in, which will improve the performance of the cooktop  1 . 
     In one aspect, also referring to  FIG. 3 , the electric machine  12  is mechanically, connected to the bottom  5 A of the apparatus  5  for the electronics for stable connection of the electric machine  12 . 
     It shall be noted that the control electronics for controlling the cooktop  1  are configured to supervise the operation of the heating elements and the operation of the devices required to draw in the cooking vapors F, i.e. the devices that form the extraction hood (the first and second cooking vapor intake chambers  6  and  8 , the fan housing  7 , the radial fan  7 A, and the electric machine  12 ). 
     The cooktop  1  comprises a vapor vent pipe  9  which, in case of a simple extraction hood (i.e. with no additional filter elements), directly fits into the fan housing  7  and, in case of a filter hood, is coupled to the fan housing  7  with a filter block interposed therebetween, the latter being formed, for instance, with one or more charcoal-based filters (highly effective in removing odors from cooking vapors F). 
     It shall be noted that the fan housing  7 , as shown in  FIG. 3 , defines a sidewall  7 B that acts as a volute, and a bottom  71 ) having an intake grille  7 E through which the second portion F 2  of the cooking vapors flows. 
     The intake grille  7 E also has such a design as to impart a regular pattern to the second vapor portion F 2  for improved fluid dynamic performance. 
     In one aspect, the bottom  7 D of the fan housing  7  and the bottom surface  1 B of the cooktop  1 , also referring to  FIG. 5  define an inflow channel  10  for the second portion F 2  of the cooking vapors. 
     The inflow channel  10  particularly extends between the bottom  4 C of the cavity  4  and the bottom  71 ) of the fan housing  7  for the radial fan  7 A. This inflow channel  10  actually forms the second cooking vapor intake chamber  8  and is placed upstream (as compared with the cooking vapor path for the second portion F 2 ) from the fan housing  7 . 
     The inflow channel  10  is configured for the second portion F 2  of the cooking vapors to be directed outwards. This outward direction is substantially parallel to the top surface of the cooktop  1  (see  FIG. 4 ). 
     It shall be further noted that the cavity  4  extends along a preset axial direction Y-Y, which is distinct from the vertical axis Y-Y′ of the radial fan  7 A or the electric machine  12 . 
     In other words, the axis Y-Y of the cavity  4  is offset from the axis Y-Y′ of the radial fan  7 A or the electric machine  12 . 
     In one aspect, it shall be noted that the inflow, channel  10  also acts as a collector for condensate, water, or other fluids. 
     Namely, the inflow channel  10  is so designed as to be able to contain a certain amount of fluids that will not be drawn in by the radial fan  7 A, and hence will not affect the operation of the electric machine  12 . 
     A hole shall be nevertheless provided on the bottom surface  1 B, with a cap  1 C for drainage of the fluids collected therein (see  FIG. 3 ). 
     In order to assess the fulfillment of the intended objects, the Applicant compared the cooktop  1 , in its extraction hood version, with the BORA® BFIA cooktop, having the features of the disclosure of WO 2012/146237. 
     Particularly, the BORA® BFIA cooktop is a cooktop with an integrated extraction hood, whose extraction components mainly include two motors, two volutes, a single downward-flowing vapor stream, which is divided into two streams within respective intake chambers only located proximate to the cooktop. 
     The results of this comparison are summarized in the following table: 
     
       
         
           
               
               
               
             
               
                   
                   
               
               
                   
                 BORA ® BFIA 
                 “Cooktop 1” 
               
               
                   
                   
               
             
            
               
                   
               
            
           
           
               
               
               
               
            
               
                   
                 Energy efficiency class 
                 B 
                  A+ 
               
               
                   
                 FDE class 
                 B 
                 A 
               
               
                   
                 FDE index 
                 23.1 
                 38.1 
               
               
                   
                 Static Pmax 
                 375 
                 700 
               
               
                   
                 Qmin m 3 /h 
                 194.8 
                 212 
               
               
                   
                 Qmin m 3 /h 
                 697.3 
                 661 
               
               
                   
                 dBAbost 
                 70 
                 69 
               
               
                   
                 GFE class 
                 B 
                 B 
               
               
                   
                   
               
            
           
         
       
     
     It should be noted that the above tests have been conducted according to the international standard “ CEI IEC  61591 : Household range hoods—Methods for measuring performance”.    
     It shall be further noted that the FDE index is the most representative parameter to assess the quality of the hood as it expresses the ratio of the work produced by the extraction unit (i.e., the fan housing  7  and the radial fan  7 A in the case of the cooktop  1 ) to the power delivered by the electric machine  12  (i.e., the electric motor  12 , in the case of the cooktop  1 ). 
     With the above in mind, as shown by the results in the table, the cooktop  1  has a considerably better energy efficiency class as compared with the BORA® BFIA cooktop. The energy efficiency class of the cooktop  1  is A+ and the energy energy efficiency class of BORA® BFIA is B. 
     This is both because the cooktop  1  uses a single motor instead of the two motors of the BORA® BFIA cooktop and especially because it has a better fluid dynamic behavior than BORA® BFIA. 
     It may be noted in this respect that the FDE index for the cooktop  1  is considerably better than that of BORA® BFIA and is about 65% higher than the FDE index that might be achieved with BORA® BFIA. 
     This advantage derives from the characteristic that the cooktop  1  has two distinct first and second cooking vapor intake chambers  6  and  8  (i.e., one located proximate to the inlet port  4 A of the cavity  4  and the other located proximate to the bottom surface  1 B of the cooktop  1 ) and, particularly, that the cooking vapor stream is divided into the first and second portions F 1  and F 2 . 
     Namely, the first portion F 1  is directed downwards toward the fan housing  7  of the radial fan  7 A and the second portion F 2  rises toward such fan housing  7 . 
     Conversely, in the BORA® BFIA cooktop, there is a single cooking vapor stream, which is a vortex flow directed toward the bottom of the cooktop and divides into two streams, also forming vortices, before entering the respective fan housings. 
     Particularly, in the BORA® BFIA cooktop, the stream only divides because the cooking vapors impinge upon the cooktop and are separated in random fashion, i.e. with a lower efficiency as compared with the separation of the two streams obtained with the cooktop of the present disclosure. 
     It shall be further noted that the configuration of the cooktop  1  is advantageous as compared with the BORA® BFIA cooktop also in terms of maximum static pressure the ability of avoiding pressure losses). 
     Those skilled in the art will obviously appreciate that a number of changes and variants may be made to the arrangements as described hereinbefore to meet incidental and specific needs. 
     All of these variants and changes fall within scope of the disclosure, as defined in the following claims.