COOKTOP HYGIENE DEVICE AND METHOD

Abstract: A cooktop hygiene device (10) removably mountable to a cooktop (93) for collecting food sputterings or spillings and preventing such sputterings from contaminating the cooktop comprises a plate-like structure (12), which can be flexible or rigid, having an upper surface (16) and a lower surface (26) adapted to interface with the cooktop surface, and a plurality of openings (24) on the plate-like structure to receive the heaters (91) on the cooktop. A fold facilitator (27) is provided on the plate like structure to facilitate the folding of the device to fit into a dishwasher. A plurality of drip pans secured to the plate-like structure is provided for catching the food and liquid spillings. The plurality of openings may be covered by heater covers to provide cooking zones on the plate-like structure to engage with the heaters. Methods for preventing the cooktop from being contaminated by food spillings using a cooktop hygiene device are provided.

Description: COOKTOP HYGIENE DEVICE AND METHOD Field of the Invention The invention relates to a device and method for maintaining cooktdps such as electric and gas ranges in a clean condition. More particularly, the invention relates to a device and method for collecting food and liquid sputterings or spillings and preventing such sputterings or spillings from contaminating the cooktops. Background of the Invention Currently, to clean cooktops such as electric and gas ranges or stoves, consumers have to manually wipe the food and liquid sputterings or spillings from the cooktop surface with cloth, sponge or paper. In addition, the food and liquid sputterings or spillings on the cooktop surface close to the heaters such as gas or electrical burners, if not removed timely or completely, may become baked on and the resulting baked-on food soils can only be removed with the assistance of special cleaning compounds and chemicals. As a result, cooktop cleaning has been ranked by consumers as the most labor-intensive and undesired work in kitchens along with food preparation and the dish washing. The baked-on food soils cause black-vanish-like coatings, making the cooktop look non- hygienic and visually unappealing. The cleaning of the cooktop surface with cleaning compounds, which are sometimes abrasive, scratches and mars the cooktop surface, making the cooktop look old and visually unappealing. New advancements in cleaning compounds have been made in an effort to improve the cleaning of the cooktop surface but the results have not proven very satisfactory. Significant progresses have also been made on ranges with smooth, easy-to-clean glass-ceramic surfaces as shown in US Pat. No. 3,987,275 to Hurko, US Pat. No. 4,740,664 to Payne and Welle, US Pat. No. 4,755,655 to Reiche et al, and US Pat. No. 5,968,371 to Deo and Griffiths. Such smooth-surface cooktops, although relatively easier to be cleaned than the traditional gas and electric rages, still require labor-intensive cleaning and suffer from the difficult-to-remove baked-on food soil problem (US Pat. No. 4,251,716 to Lewis and Hurko). In addition, such smooth glass-ceramic surface ranges are too expensive for average consumers. It is therefore an object of the invention to provide a product to free consumers from the labor-intensive and unpleasant work of cleaning cooktops. It is a further object of the invention to provide consumers a device that prevents the food and liquid spillings or sputterings from staining the cooktop surfaces and is washable by a dishwasher or a wash machine. It is a still further object of the invention to provide a product that makes it unnecessary to clean the cooktops, therefore freeing the cooktops from being scratched and marred. It is a still further object of the invention to preserve the newness and fresh look of a cooktop for a long period of time and to elongate the life of the cooktop. It is a still further object of the invention to provide a device that is large enough to cover a cooktop surface but is easy to store, transport, handle and wash. It is a still further object of the invention to provide a device that covers a cooktop surface without making it inconvenient for a consumer to access the electric or gas burners of the cooktop. It is a still further object of the invention to provide a device to convert a traditional cooktop or range into a smooth-surface cooktop to facilitate the cleaning. It is a still further object of the invention to provide a device that covers a cooktop surface as well as covers or replace the drip pans in a traditional cooktop. It is a still further object of the invention to provide a cooktop hygiene device whose dimension can be changed.by a user to fit his or her specific cooktop. Still other objects will become apparent after reading the accompanying drawings and description. It should be understood that the invention could still be practiced without performing one or more of the objects set forth above. Summary of the Invention Accordingly, the invention provides a cooktop hygiene device for collecting food and liquid sputterings or spillings and preventing such sputterings or spillings from contaminating the cooktops. The device comprises a plate-like structure removably mountable onto the cooktop for preventing food and liquid spillings or sputterings from contaminating cooktop surface. The plate-like structure, which can be either flexible or rigid, comprises an upper surface adapted to receive food and liquid spillings or sputterings from cookware or utensil during food preparation process, a lower surface adapted to interface with the surface of the cooktop, a plurality of openings located on the plate-like structure to receive the heaters on the cooktop and to allow a user can place a cookware or utensil on or above a heaters for heating the content in the cookware or utensil when the cooktop hygiene device is mounted to the cooktop. A fold facilitator may be formed on said plate like structure to facilitate the folding of the plate-like structure. The cooktop hygiene device further comprises an anti-motion mechanism to prevent the plate-like structure from movement on the cooktop surface. A plurality of drip pans secured to said plate-like structure may be positioned below the heaters of the cooktop for catching food and liquid spillings or sputterings from cookware or utensil during food preparation process. The openings for receiving the heaters may be formed directly on the cooktop if the plate-like structure comprises a plate material that can be melted softened or degraded when exposed to the high heat from the heaters on the cooktop. A plurality of covers may be connected to the plate-like structure for covering the openings or heaters by hinges. The hinge may comprise an extension to position the covers away from the heaters to avoid the covers from blocking the access to the heaters when the covers are opened. In another embodiment of the invention, the cooktop hygiene device comprises a first plate-like structure having an upper surface for receiving food and liquid spillings or sputterings from cookware or utensil during food preparation process and a lower surface adapted to interface with the surface of the cooktop, a second plate-like structure comprising an upper surface for receiving the food and liquid spillings or sputterings from cookware or utensil during food preparation process and a lower surface adapted to interface with the surface of the cooktop, and a connector for connecting the first platelike structure to said second plate-like structure in such as way to enable a user to reduce the dimension of said cooktop hygiene device to fit into a dishwasher for cleaning the cooktop hygiene device. In one configuration, the connector comprises a flexible or bendable material or a hinge to allow a user to fold said plate-like structure. In another configuration, the connector comprises a first connection member located on the first plate-like structure and a second connection member located on the second plate-like structure to interface with the first connection structure to prevent the food or liquid spillings or sputterings from passing through said plate-like structure. In still another configuration, the connector comprises a first chamber to receive at least part of the first plate-like member and a second chamber to receive at least part of the second plate-like structure. In still another configuration, the connector comprises an expandable member such as a pleated member or an expandable material to allow a user to change the dimension of the cooktop hygiene device to fit the cooktop. In another embodiment of the invention, the cooktop hygiene device is removably mountable to the cooktop and comprises a plate-like structure having a first surface for receiving the food and liquid spillings or sputterings from cookware or utensil during food preparation process and a second surface adapted to face the surface of the cooktop and a plurality of cooking zones on said plate-like structure for engaging with the heaters on the cooktop and for conducting heat from the heaters to cookware or utensil on or above said cooking zones. The plate-like structure is generally impermeable to the food and liquid spillings or sputterings collected on said first surface thereby preventing the food and liquid spillings or sputterings from contaminating cooktop surface. In one configuration, the plate-like structure is adapted to be anisotropic in heat conductivity so that the heat from the heaters on the cooktop is substantially confined within the cooking zones. In another configuration, the plate-like structure comprises numerous solid pieces connected to each other by narrow connectors and separated from each other by air gaps. The narrow connectors are sufficiently narrow or thin to minimize the heat conduction between the solid pieces thereby preventing or limiting the heat conduction along the surface of the cooking zones and the plate-like structure. The air gaps are made sufficiently small or filled with heat insulation materials to prevent the food or liquid spillings or sputterings to be collected on the first surface of the plate-like structure from passing through. In still another configuration, the cooktop hygiene device further comprises heat restriction zones surrounding the cooking zones for preventing or limiting the heat flow from the cooking zones to the other part of said cooktop hygiene device. The cooktop hygiene device may further comprise a raised wall around at least one of said cooking zones to convert at least one cooking zone into a cookware for cooking food. The cooktop hygiene device may further comprise air vent for providing air to the heaters if the heaters are gas heaters. The cooking zones may comprise raised or recessed structures for increasing the surface area thereby improving the heat transfer from the cooking zone to the surrounding. A coating such as a Teflon, elastomer, glass or ceramic coating may be applied to at least the surface of said cooking zones of said cooktop hygiene device. Another aspect of the invention is a method for preventing the surface of the cooktop from being contaminated by food and liquid spillings or sputterings thereby reducing or even eliminating the need to clean the surface of the cooktop. The method comprising mounting a cooktop hygiene device comprising a plate-like structure generally impermeable to the food and liquid spillings or sputterings onto the cooktop, collecting the food and liquid spillings or sputterings from cookware or utensils during food preparation process onto the upper surface of the plate-like structure, and removing the cooktop hygiene device from the cooktop for the purpose of washing or disposing the cooktop hygiene device after the user determines that there is too much food and liquid spillings or sputterings collected on the upper surface of the plate-like structure. The method may further comprise a step of folding the plate-like structure to reduce the size of the cooktop hygiene device to fit into the dishwasher. Description of the Drawing The accompanying drawing illustrates diagramatically non-limitative embodiment of the invention, as follows: Fig. 1 is a perspective view of a cooktop hygiene device and part of a cooktop; Fig. la is a sectional view along line la-la of Fig. 1; Fig. lb is a front view of the cooktop hygiene device of Fig. 1 in a folded position; Fig. 2 is a perspective view of an alternative cooktop hygiene device and part of a cooktop; Fig. 2a is a sectional view along line 2a-2a of Fig. 2; Figs. 2b is a front view of the alternative cooktop hygiene device of Fig. 2 in a folded position; Fig. 3 is a perspective view of a further alternative cooktop hygiene device; Fig. 3a is a sectional view along line 3a-3a of Fig. 3; Fig. 3 b is a sectional view of a removable cover for use with cooktop hygiene device of Fig. 3; Fig. 3 c shows a modified version of the cooktop hygiene device of Fig. 3. Fig. 3e shows a plurality of cooktop hygiene devices rolled on a core; Fig. 3f shows one of the cooktop hygiene devices of Fig. 3e mounted on a cooktop; Fig. 3g shows the forming of the openings for a cooktop hygiene device of Fig. 3e on a cooktop; Figs.3h to 3j shows several alternate plate-like structures 12 having anise-tropic heat conductivity; Fig. 4 is a partly perspective, partly top view of a further alternative cooktop hygiene device Fig. 4a is a sectional view along line 4a-4a of Fig. 4; Figs. 5 to 5c are sectional views for the alternatives to the cooktop hygiene device of Fig. 4; Figs. 6 and 6a are section views of further alternatives to the cooktop hygiene device of Fig. 4; Fig. 7 is a perspective view of a still further alternative to the cooktop hygiene device of Fig. 1; Fig. 7a is a sectional view along line 7a-7a of Fig. 7; Figs. 7b and 7c are sectional views for the modified versions of the cooktop hygiene device of Fig. 7 having a different connectors 27; Fig. 8 is a perspective view of a still further alternative to the cooktop hygiene device of Fig. 1; Fig. 8a is a sectional view along line 8a-8a of Fig. 8; Fig. 8b is a sectional view for a modified version of the cooktop hygiene device of Fig. 8 with a different connector 27; Fig. 9 is a sectional view of a still further alternative cooktop hygiene device and part of a cooktop shown in dotted lines; Fig. 9a is a top view of the cooktop hygiene device and part of a cooktop of Fig. 9; Fig. 10 is a sectional view of a even still further alternative cooktop hygiene device and part of a cooktop shown in dotted lines; Fig. 10a is a top view of the cooktop hygiene device and part of a cooktop of Fig. 10; Detailed Description of the Preferred Embodiments Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. Fig. 1 shows part of a cooktop 90 having four gas or electric heaters (or burners) 91 located on a cooktop surface 93 comprising a recessed cooktop surface 93a and a raised peripheral surface 93b and a cooktop hygiene device 10 removably mountable to the cooktop for collecting the food and liquid sputterings or spillings from the cookware or utensils during the cooking processes. The cooktop hygiene device 10 comprises a plate-like structure 12 generally impermeable to food, thereby preventing such sputterings or spillings from reaching the cooktop surface 93. The plate-like structure 12 comprises an upper surface 16 for receiving food and liquid spillings or sputterings from cookware or utensils during food preparation processes, a lower surface 26 configured to engage with the cooktop 90 to prevent movement of the cooktop hygiene device on the cooktop, and four openings 24, each opening having an internal peripheral wall 23, dimensioned to receive the four heaters 91 on the cooktop and to allow the user to place cookware or utensils on the heaters. To fit the contour of the cooktop surface, the plate-like structure has a recessed part 12a dimensioned to cover the recessed cooktop surface 93a and a raised part 12b dimensioned to cover the raised peripheral surface 93b of the cooktop. The part of the lower surface 26 under the recessed part 12a of plate-like structure 12 can be in contact with the recessed cooktop surface 93a to reduce the movement of the cooktop hygiene device. The openings 24 on the plate-like structure 12 are dimensioned and positioned primarily according to the size and location of the heaters 91 on cooktop 90, The peripheral edge of the openings 24 may be raised approximately 0.1 to 2 cm to prevent the food or liquid sputterings or spillings from dropping or overflowing into the interior of the cooktop 90. The raised peripheral edge can be as high as the heater or the support such as grates for cookware. The plate-like structure 12 may be configured to cover the control panel of the cooktop (not shown), thus preventing the control panel from being contaminated by the sputterings or spillings, too. The upper surface 16 is preferably made smooth and non-sticky to facilitate the cleaning or the removal of the food and liquid sputterings or spillings during manual or dishwasher washing of the cooktop hygiene device. The part of the lower surface 26 that is in contact with the cooktop surface 93 is preferably made to have sufficiently high coefficient of friction or even made sticky to limit or prevent the movement of the cooktop hygiene device on the cooktop. The recessed part 12a of the plate-like structure 12 may be dimensioned to fit sufficiently tightly into the recessed cooktop surface 93a to prevent the movement of the device. Other anti-motion mechanisms, such as magnet powders impregnated in or magnet strips attached to the plate-like structure 12, electrostatic adhesives or pressure sensitive adhesives or surface tackifiers applied to the plate-like structure, and vacuum suck cups attached to or formed on the plate-like structure, may be used to limit or prevent the movement of the cooktop hygiene device on the cooktop. To allow the cooktop hygiene device 10 to fit into a conventional dishwasher, the device dimension must be reduced. Fig. lb shows that after being removed from the cooktop, the cooktop hygiene device can be folded around a connector or fold facilitator 27, resulting in a left-hand plate-like member 15 and a right-hand plate-like member 14 of the plate-like structure 12. The folded cooktop hygiene device is small enough to fit into a conventional dishwasher. The fold facilitator 27 comprises a thin, flexible strip 30 connecting the left part 15 and right part 14 of the plate-like structure 12 into one continuous plate. The front and back sides of the raised peripheral surface 12b of the cooktop hygiene device are cut, as indicated by lines 28, at the fold facilitator 27 to facilitate the folding of the plate-like structure 12. The thin strip 30 may comprise the same material as the left part 15 and right part 14 of the plate-like structure or may be formed together with left part 15 and right part 14. The thin strip may also comprise materials different from the left part 15 and right part 14. The preferred materials for the thin strip 30 are flexible materials such as elastomer and thin plastics. Other types of fold facilitators or connectors, such as hinges, magnetic connectors and expandable connectors, some of which will be described in more detail later, may be used to replace the fold facilitator 27 here. It is appreciated that the fold facilitator or connector 27 becomes unnecessary if the plate-like structure is flexible and can be bent, folded or rolled to fit into a dishwasher. A side benefit of the foldability or flexibility of the plate-like structure 12 is that it enables the cooktop hygiene device to take less space during transportation, storage and on retail shelves. The cooktop hygiene device further comprises four heater covers 11 to enable the user to Close the openings 24 (refer to the two heater covers 11 at the right hand of Fig. 1) when the corresponding heaters are not in use and to open the openings 24 (refer to the two heater covers 11 at the left hand of Fig. 1) when the corresponding heaters are not use. These heater covers help preventing the food and liquid sputterings or spillings from contaminating the heaters or the drip pans below the heaters during the cooking or food preparation process. Each heater cover 11 has a side wall 19, a top wall 29 and a chamber 17 formed by the side wall and the top wall for receiving the heater 91 of the cooktop 90. The heater cover 11 is connected to the plate-like structure 12 via a hinge 21. To insure that the heater cover 11 will not prevent a cookware or utensil from contacting the heater 91 properly, an extension 20 is used between the heater cover and the plate-like structure so that the heater cover can be sufficiently away from the opening 24. A space 22 is formed on the plate-like structure to receive the extension 20 when the heater cover 11 closes the opening 24. The heater cover 11 is dimensioned to fit into the opening 24 when it closes the opening, although it is appreciated that the heater cover can be larger than the opening 24 and as a result it rests above the plate-like structure when it is in its close position. It is appreciated that the heater cover 11 can also be constructed to allow its top wall 29 to function as a cooking zone for conducting heat from the heater 91 to the cookware or utensil on the heater cover. In this case, the heater cover may be formed of highly heat-resistant materials such as stainless steel, cast iron, glass or ceramic materials. The top wall 29 may be configured to increase the surface area, therefore increasing the rate of heat transfer from the wall 29 to the surrounding. The faster heat transfer to the surrounding reduces the potential damage of the heater cover 11 by the heater 91. The surface area of the top wall 29 can be increased, for example, by forming raised or recessed structures such as discs, ridges or cells on the upper surface of the top wall 29. A plurality of air vents, such as holes or openings on the side wall 19, may be formed on the heater covers to provide air to the burners if the cooktop hygiene device is used for a conventional gas cooktop or range. A handle or tab 18 is attached to or formed on the heater cover 11 for allowing the user to readily open and close the opening 24. The heater cover 11 may further comprise a locker to prevent the heater cover from free movement when it closes the opening 24, which proves to be useful during the handling and washing (e.g. in a dishwasher) of the cooktop hygiene device. The lock of the heater cover position may be achieved by the tight fit between the side wall 19 of the heater cover and the inner peripheral wall 23 of the opening 24 or by the appropriate tapering of the wall 19 and the inner wall 23 (e.g. the wall 19 of the heater cover has increasing diameter and the inner wall 23 of the opening 24 has decreasing diameter from top to bottom). The locker may also be a simple mechanical locking mechanism such as a catch and latch formed on the handle 18 and the plate-like structure 12, an adhesive applied to handle or tab 18 or the heater cover, or a magnet included in the handle or tab 18, heater cover 11 and/or the plate-like structure 12. To insure that the cooktop hygiene device will not catch fire when it is close to or even in contact with the heater 91 when the heater is on, the plate-like structure 12 and the cover 11 of Figs. 1 to 10 are preferably formed of non-flammable material or materials. Such non-flammable materials include most metals and their alloys, ceramic materials, glass materials, oxides, non-flammable polymers (e.g. certain plastics, rubbers and thermoset materials such as Teflon and Kevlar), polymers with flame- retardant additives, and any combinations of these materials. Typical examples are stainless steel, aluminum, highly fluorinated polymers (e.g. Teflon), substantially wholly aromatic polymers that do not produce flammable gas at over 750° F (e.g. Kevlar, polyphenyl sulfide, polyphenyl oxide and polyphenyl quoixolines), and silicone rubbers. When polymeric material or materials are used for the plate-like structure 12 and the cover 11, high-density inorganic fillers such as glass powder, stainless steel powder, calcium fluoride, rock powder, graphite, or sand powder can be used to reduce the formation of curl, wrinkles and kinks on the plate-like structure and the heater cover. The inorganic fillers may also reduce the materials cost of the device and the flammability. The plate-like structure 12 and heater covers 11 of the cooktop hygiene devices 10 of Figs. 1 to 10 can be formed from sheet or film materials such as stainless steel sheet, zinc sheet, aluminum foil, Teflon film and silicone rubber sheet and from woven or non-woven materials such as stainless steel cloth (with or without Teflon or ceramic coating), glass fiber cloth and Kevlar cloth. The manufacturing processes involved may include thermoforming, metal forming, heat sealing, welding, and die or laser cutting. To prevent the exposed edges of the plate-like structures 12 and heater covers 11 shown in Figs. 1 to 10 from injuring or cutting people, the exposed edges may be rounded, flanged, coated with softer materials such as plastics or elastomer, or made thicker than the inside areas. Such treated edges is found to greatly reduce the risk of cutting fingers when metal, glass, ceramic and other hard materials are used for the plate-like structure and heater covers. The cooktop hygiene devices 10 can also be manufactured by molding, casting or extrusion of plastic, elastomer, ceramic, glass, oxide, metal or metal alloy materials. Decorative coatings such as ink printing, porcelain enamel, paint and stamping can be provided on the surface of the plate-like structure 12 and heater covers 11 of the cooktop hygiene devices 10. Figs. 2 to 2b show a modified version of the cooktop hygiene device of Fig. 1. This modified device has generally flat heater covers 11, compared to the relatively more complex, cup-shaped heater covers of Fig. 1, and can thus be manufactured from sheet or film or woven cloth materials by simple processes such as die cutting. Anti-motion mechanism 33 is included on at least the corners of the modified cooktop hygiene device to prevent the device from free movement after the device is mounted onto the cooktop. The anti-motion mechanism can be magnets, adhesives (such as electrostatic adhesive, pressure sensitive adhesive or tackilifiers) and vacuum suck cups attached to or formed into the plate-like structure 12. A device handle or tab 34 is located near the peripheral edge of the plate-like structure for facilitating the removal of the plate from the cooktop 90. This modified device is ideal for the cooktops, such as the smooth glass or ceramic cooktops, whose heaters are at or only slightly above the cooktop surface 93. For the traditional electric and gas cooktops whose heaters or grates are significantly above the cooktop surface 93, the extension 20 of the hinge 21 for each heater cover 11 can be made sufficiently long to allow the heater cover 11 to cover the top surface of the heaters or grates. The fold facilitator 27 comprises a plurality of cuts 30a near the center line of the plate-like structure to facilitate the folding of the modified device. If the film or sheet or cloth material used to form the plate-like structure is flexible enough, the fold facilitator 27 may not be needed, which further simplifies the manufacturing process and lower the cost. If the plate-like structure is formed of flexible materials, especially if of woven cloth, the cooktop hygiene device may be washed by either dishwasher or cloth wash machine. When the manufacturing cost becomes low enough, the cooktop hygiene devices of the invention can be disposed when becoming dirty after one use, therefore completely eliminating the cleaning work related to cooktops. For disposable cooktop hygiene devices, degradable materials such as biodegradable, air-degradable, or water-degradable or light degradable materials may be used to address potential environmental concerns. Figs. 3 and 3a shows another modified version of the cooktop hygiene device of Fig. 1. This modified device can also be manufactured from flexible sheet or film or woven cloth materials by simple processes such as die cutting. Two elongated support members 35 are located at the left and right ends of the plate-like structure 12 to facilitate the handling of the flexible plate-like structure, thus facilitating the handling, washing and storage of the cooktop hygiene device. The elongated support member can be a bar, rod, strip, beam or tube and can be mechanically or thermally attached to the platelike structure 12. The elongated support member can also be formed by rolling or flanging the plate-like structure if the plate-like structure is made of metal or alloy (e.g. aluminum or stainless steel) film, sheet or cloth. The elongated support member 35 can be configured to apply force(s) or tension to the plate-like structure 12 to prevent it from free movement on the cooktop surface. For examples, the support member 35 may comprise magnet, mechanical lock or adhesive to cause itself to attach to the cooktop, therefore limiting the movement of the plate-like structure. The elongated support members 35 on both ends of the plate-like structure may be weight bars, rods or tubes hanging on the corresponding sides of the cooktop to tension the plate-like structure 12, therefore limiting the movement of the plate-like structure on the cooktop. The elongated support member 35 can also be configured to cause the plate-like structure, if made of flexible film, sheet or woven cloth, to conform to the contour of the cooktop surface. For example, if the cooktop hygiene device is designed for the cooktop of Fig. 1, the elongated support member can have a downward extension to push the center portion of the flexible plate-like structure to the recessed cooktop surface 93a and have two ends to push the front and back ends of the flexible plate-like structure to a raised peripheral surface 93b of the cooktop. Fig. 3b shows a removable heater cover 11 having a chamber 17 for receiving the heater 91 of the cooktop for use with this modified cooktop hygiene device. A flat heater cover 11 like that in Fig. 2 can also be used with this device, especially if the cooktop is a glass/ceramic smooth-top cooktop or range. If desired, the heater cover can be connected to the plate-like structure with hinge 21. Fig. 3 c shows a third elongated support member 35 positioned near the center of the platelike structure 12 to further facilitate the handling (e.g. folding or rolling) of the plate-like structure 12. It is appreciated more than three or fewer than two elongated support members 35 may be attached or formed at the plate-like structure. The elongated support member may be un-necessary if the plate-like structure 35 is thick or strong enough to be handled readily. Fig. 3e shows a plurality of cooktop hygiene devices 10 that are wound on a core 92 to form a roll 25. Each cooktop hygiene device 10 in the roll 25 comprises a flexible plate-like structure 12 having an upper surface 16 for collecting the food and liquid spillings or sputterings and a lower surface for interfacing with the surface of the cooktop. The flexible plate-like structure 12 has approximately the same dimension, i.e. width and depth, as the surface of the cooktop to which the cooktop hygiene device is to be mounted. It is generally impermeable to the food and liquid, therefore preventing the food and liquid spillings or sputterings on the upper surface 16 from reaching the lower surface or the cooktop surface. Such impermeable flexible plate-like structure may be made of heat-resistant, non-flammable film, foil, sheet, or woven or non- woven cloth. An elongated support member 35 can be attached to or formed at each end of the flexible plate-like structure 12 to facilitate the handling of the cooktop hygiene device. (More or fewer than two elongated support members 35 can be attached to or formed on each cooktop hygiene device). The cooktop hygiene devices 10 in the roll 25 are joined to one another by joint strip 100 having a perforated line 101 to facilitate the removal of the device from the roll 25. Alternately, the cooktop hygiene devices in the roll 25 may be wounded as separate entities without any joint between the devices. The cooktop hygiene devices in the roll 25 may also be separated from each other by a simple perforated line or by a line mark and be removed from the roll by tearing along the perforated line or cutting with a cutter along the line mark. Such method of packaging cooktop hygiene devices can be used for other cooktop hygiene devices having plate-like structures 12 that are flexible. Fig. 3f shows a cooktop hygiene device 10, similar to those in Fig. 3e, mounted to the cooktop 90. The plate-like structure 12 of the device covers the heaters 91 and cooktop surface. In one embodiment, the plate-like structure 12 is made of highly heat-resistant materials such as stainless steel, high-temperature aluminum alloy, glass and ceramic materials. Such plate-like structure 12 can survive over direct or close contact with the heaters 91. To prepare food, the user simply places the cookware or utensil on the area of the plate-like structure that is directly above a heater 91, i.e. on the cooking zone of the plate-like structure. The cooking zone conducts heat from the heater to the cookware or utensil. To indicate to the user the precise location of each heater 91 below the cooktop hygiene device, certain heat resistant marks (e.g. a circle or radiant lines) may be printed or formed on the cooking zones of the platelike structure. The plate-like sttucture can also be made transparent or translucent to let the user see through the plate-like structure to locate the heaters. Small holes, in the range of approximately 0.0001" to 0.1" (preferably 0.01" to 0.1"), may be formed on the plate-like structure let the user see through the platelike structure to locate the heaters without letting any significant amount of food or liquid spillings or sputterings pass through the plate-like structure. The cooktop hygiene devices 10 of Fig. 3f can be used for conventional electric or gas cooktops or ranges. For gas cooktop, a plurality of air vents such as holes can be formed on the plate-like structure 12 to supply air to the gas heaters. The cooktop hygiene device 10 can also be used for glass/ceramic smooth-top range. To reduce potential damage of the plate-like structure 12 by the heaters 91, the plate-like structure or only the sections of the plate-like structure that are directly above the heaters, i.e. the cooking zones, can be configured to increase the surface area, therefore increasing the rate of heat transfer from the cooking zones to the surroundings. The surface area of the plate-like structure or the cooking zones can be increased, for example, by forming raised or recessed structures such as discs, ridges or cells on the upper surface of the plate-like structure 12 or the cooking zones. In another embodiment of the cooktop hygiene device 10 of Fig. 3f, the plate-like structure 12 is made of material(s) that is heat-resistant, but not resistant enough to withstand the heat from direct or close contact with the heaters 91 of the cooktop. Examples of such materials include low-temperature aluminum alloy, Teflon, Kevlar, silicone rubber and other materials that are inherently non-flammable or can be blended with flame-retardant additives. After the cooktop hygiene device is mounted onto the cooktop 90 as shown in Fig. 3f and after the heaters 91 are turned on, the heater temperature raises quickly to the melting point or decomposition point of the plate-like structure. The regions on the plate-like structure which are directly on the heaters 91 and sufficiently close to the heaters become melted, decomposed, burned or evaporated by the high temperature of the heaters. As a result, openings 24 having approximately the size of the corresponding heaters 91 are formed or partially formed in the plate-like structure for the heaters 91 on the cooktop 90 (refer to Fig. 3g). The openings 24 allow the user to place cookware or utensil directly on or above the heaters 91. By forming or partially forming the openings 24 for the plate-like structure 12 directly on the cooktop 90, the consumers do not need to spend the effort to select the cooktop hygiene devices with the right openings 24 to match the size, shape and position of their cooktops. The plate-like structure 12 and heater cover 11 of Figs. 1 to 10 can be made of anise-tropic material(s) that has high heat conductivity across the thickness of the plate-like structure or heater cover but low heat conductivity along the surface of the plate-like structure or heater cover. An example of such anisotropic materials is a film or sheet having conductive entities 110 such as particles, beads, plates, discs or short wires dispersed, either randomly or regularly, in the film or sheet. The concentration of such conductive entities in the film or sheet can be sufficiently low to reduce direct contact between adjacent conductive entities along the surface. To achieve significant increase in conductivity across the thickness of the plate-like structure or heater cover, the dimension of the conductive entities is at least approximately 1/8, preferably at least 1/3, of the thickness of the plate-like structure or heater cover. Figs.3h and 3i show part of a plate-like structure 12 or heater cover 11 in which conductive entities 110 having dimensions equal to and greater than the thickness of the plate-like structure or heater cover are used, respectively. Another example of such anisotropic materials is a film, sheet, plate or woven cloth having air gaps between the solid pieces. The solid pieces can be miniature plates, rings, strips, wires, discs, etc. The solid pieces themselves can be porous or nonporous. The solid pieces are connected to each other by U narrow connectors strips or lines sufficiently narrow or thin to minimize the heat conduction between the solid pieces. The air gaps between the solid pieces may be filled with heat insulation materials to prevent the food or liquid spillings or sputterings on the upper surface 16 from passing through the gaps to the lower surface 26 of the plate-like structure 12. The air gaps can also be made narrow or small enough to prevent the food or liquid spillings or sputterings from penetration. Fig. 3j shows part of a plate-like structure made of numerous small thin plates 111 separated from each other by air gaps 112 and connected to each other by narrow connectors 114. The air gaps 112 can be small enough or can be filled with heat insulation material to prevent the food or liquid spillings or sputterings from passing through the plate-like structure. The materials for the solid pieces such as miniature plates, rings, strips, wires, discs and the arrow connectors such as narrow strips or lines can be stainless steel, aluminum or its alloy, steel, and other structurally durable materials. It is appreciated that such anisotropic materials can also be used for the heater covers 11. Figs. 4 and 4a show another alternative to the cooktop hygiene device 10 of Fig. 1. In the alternative cooktop hygiene device, the heater covers 11 are attached to the plate-like structure 12 via the peripheral extension 42 of the heater covers. A heat-restriction ring 41 is formed between the peripheral extension 42 and the top wall 29 of the heater cover 11 to enable a large temperature drop from the top wall 29 to the peripheral extension 42 when the heater 91 is on (Fig. 4a). The heat-restriction ring 41 comprises a plurality of air gaps 106 and a plurality of narrow connectors 107 (Fig. 4 shows three air gaps and three narrow connectors). The construction allows the top wall 29 of the heater cover to become the cooking zone and conducts heat from the heater 91 received in chamber 17 of the heater cover 11 to the cookware or utensil on the top wall 29. It also makes the upper surface 16 of the plate-like structure 12 feel cool. To withstand temperatures up to that of the heater 91 , the heater cover 11 is made of highly heat- resistant materials(s) such as stainless steel, cast iron, glass or ceramic materials. The air gaps 106 may be made larger to function also as the vents to provide sufficient air to the burners if the cooktop hygiene device is mounted to a conventional gas cooktop or range. The air gaps 106 can be made very narrow to prevent the food and liquid sputterings or spillings from passing through. The air gaps can also be filled with heat-insulation materials to prevent the food and liquid sputterings or spillings from passing through. More than one heat-restriction ring 41 may be formed between the top wall 29 of the heater cover, i.e. the cooking zone, and the plate-like structure 12. It is also appreciated that such heat-restriction rings can be formed throughout the heat cover and the plate-like structure. Fig. 5 shows a modified version of the cooktop hygiene device 10 of Fig. 4. In Fig. 5, the plate-like structure 12 is made of the same highly heat-resistant materials(s) as the heater covers 11. The heater cover 11 and the plate-like structure 12 are connected via heat restriction zone 41. The left part 15 and right part 14 of the plate-like structure are connected by the fold facilitator 27 comprising a hinge 47 to allow the cooktop hygiene device to fold to fit into a conventional dishwasher. Fig. 5a shows a modified version of the cooktop hygiene device 10 of Fig. 5. In this modified cooktop hygiene device, the top surface 16 of the plate-like structure 12 is coated with coating 85 such as Teflon or Silicone rubber and the top wall 29 (i.e. the cooking zone) of the heater cover 11 is coated with an inert, highly heat-resistant materials such as glass or ceramic materials. Fig. 5b shows another modified version of the cooktop hygiene device of Fig. 5 in which the heater covers 11 are flat discs connected to the plate-like structure 12 via heat restriction zone 41. The heater cover 11, as the cooking zone, conducts heat from the heater 91 of the cooktop 90 to the cookware or utensil siting on the wall 29 of the heater cover. Numerous spaced- apart conductive objects such small metal bars or discs may be dispersed in the heater covers 11 and platelike structure 12 to increase the heat conduction from the lower surface 26 to upper surface 16 drastically without impacting the heat conduction along the surface to any significant degree, therefore making the plate-like structure anisotropic. Fig. 5c shows a modified version of the cooktop hygiene device of Fig. 5b in which at least one of the heater covers 11 is surrounded by a raised wall 83 to form a pan 87 for the user to cook or prepare food therein. The top wall 29 of the heater covers 11 can be coated with inert, heat-resistant coatings such as Teflon, glass or ceramic materials. The upper surface 16 of the plate-like structure 12 can be coated with heat-resistant polymer such as Teflon or polyimide, rubber material such as silicone, glass or ceramic material. It is appreciated the heater covers 11 can be made of heat conductive and durable materials such as stainless steel, cast iron and steel to increase the efficiency of conducting heat from heaters 91 across the top wall 29 to the cookware or cooking utensil. Various heat restriction mechanisms such as heat restriction zone 41, ultra-thin wall thickness and anisotropic materials may be used to decrease the heat conduction rate from the cooking zones to the rest of the cooktop hygiene device. Fig. 6 shows another alternative to the cooktop hygiene device of Fig. 1. This alternative cooktop hygiene device comprises a highly heat-resistant, flexible or foldable sheet 12 such as a woven or non-woven cloth made of metal, glass or ceramic fibers or a thin film made of heat-resistant metal, glass or ceramic materials. This heat-resistant, flexible or foldable sheet is comparable to plate-like structure 12 in the earlier examples. Preferably, the fibers or materials(s) used for the flexible or foldable sheet 12 can withstand temperatures higher than 1000° F so that it may not be significantly damaged upon close contact with the heaters 91 of the cooktop 90. A coating layer 77 may be applied to the upper surface 16 of the flexible or foldable sheet 12 in such a way that openings 24 surrounded by peripheral wall 23 are formed at predetermined locations on the flexible or foldable sheet. The openings 24 are dimensioned and positioned on the flexible or foldable sheet in such a way that the heaters 91 on the cooktops are directly below the openings 24 and approximately within the peripheral wall 23 of the openings after the cooktop hygiene device is mounted onto the cooktop 90. The opening 24 allows a cookware or utensil to be placed directly on the area of the flexible or foldable sheet surrounded by peripheral wall 23 or the cooking zone, thereby increasing the heat conduction rate from the heater to the cookware. The coating layer 77 is made of heat-resistant materials) such as Teflon, Silicone, ultra-thin glass or ceramic materials. To facilitate the folding or rolling of the flexible or foldable sheet 12, elongated support members 35 (similar to that in Figs. 3-3c) are attached to or formed at the left and right ends of the flexible or foldable sheet 12. Fig. 6a shows a modified version of the cooktop hygiene device 10 of Fig. 6. In this modified cooktop hygiene device, the coating layer 77 completely covers the upper surface 16 or the flexible or foldable plate-like structure 12. The coating 77, in one embodiment, is resistant to the high temperature caused by the heaters 91 and will stay intact during the use of the cooktop hygiene device on the cooktop. The cooking zones on the plate-like structure are the sections of the plate-like structure 12 that are directly above the heaters 91. Examples of such highly heat-resistant coating materials are glass and ceramic materials. In another embodiment, the coating 77 is heat-resistant but is not heat-resistant enough to withstand the high temperature on the heater 91. Examples of such limited heat resistant coating materials are Teflon, silicone rubber, epoxy thermosets, and other polymers with or without flame- retardant additives. The preferred materials are those that release no harmful substances when exposed to high heat and are not flammable. After the cooktop hygiene device is mounted to the cooktop and the heaters are turned on, those regions of the coating 77 on the plate-like structure 12 which are directly above the heaters 91 may be burned, melted or evaporated by the high temperature caused by the heaters. One opening 24 having approximately the size of the corresponding heater 91 is formed in the coating 77 on the plate-like structure for each heater 91 on the cooktop 90. As a result, the cooktop hygiene device of Fig. 6a is converted into that of Fig. 6. Since the heaters 91 in different cooktops may have different sizes, shapes and positions, it is somewhat difficult for consumers to select the right cooktop hygiene devices with the right openings 24 for their cooktops. This method of forming the openings 24 directly on the cooktop makes the selection process much easier since a user does not need to get a cooktop hygiene device with the right openings 24 to match the heaters on the user's cooktop. It is appreciated that the plate-like structure 12 may be a porous plate such as a metal film or sheet containing numerous punched holes, a woven or non-woven cloth made of fibers such as thin stainless steel or glass fibers, and a porous metal or ceramic film. The coating 77 can be within the pores or gaps of the porous plate, on one surface of the porous plate, on both surfaces of the porous plate, both within the pores or gaps and on one surface of the porous plate, or both within the pores or gaps and on both surfaces of the porous plate. In all cases, the coating 77 on or in the porous plate regions that are directly above the heaters 91 is burned, melted or evaporated by the high temperature caused by the heaters. As a result, only the part of the porous plate that is away from the heaters remain coated with coating 77. Figs. 7 and 7a show a modified version of the cooktop hygiene devices 10 of Figs. 2 and 3. In this modified cooktop hygiene device, the folding facilitator or connector 27 comprises an expandable member such as a corrugated or pleated section 51 that can be elongated or shortened by stretching or compressing. Such connector 27 enables the user or consumer to adjust the distance between the two openings on the left plate-like member 15 of the plate-like structure 12 and the two openings on the right plate-like member 14 to fit to his or her cooktop. The folding facilitator or connector 27 in Fig. 7b comprises a section of expandable material 52 having shish-kabab or row-lamellar structure. Examples of such expandable material include semi-crystalline polymers such as polypropylene and fibrous materials such as expanded Teflon. The expandable material 52 allows the user to increase the distance between the openings on the left member 15 and the openings on the right member 14 of the plate-like structure 12 to fit to his or her cooktop. The folding facilitator or connector 27 in Fig. 7c comprises a mechanical connector 55 comprising a left claw 56b with a thin chamber 54a to receive a small portion of the left plate-like member 15 of the plate-like structure 12, a right claw 56a with a thin chamber 54b to receive a small portion of the right plate-like member 14 of the plate-like structure 12, and a flexible or foldable section 30 for connecting the left and right claws. To change the distance between the openings on the left part 15 and right part 14 of the plate-like structure 12, the user simply pulls or pushes the left part 15 or/and right part 14 out of or into the thin chambers of the mechanical connector 55. It is appreciated that the flexible or foldable section 30 of the mechanical connector 55 may not be needed since the dimension of the cooktop hygiene device may be reduced enough to fit into a dishwasher by pushing the left and right plate-like members into the thin chambers 54a and 54b. Figs. 8 and 8a show another modified version of the cooktop hygiene device 10 of the earlier exemplar embodiments. The connector 27 of this modified cooktop hygiene device comprises a first connection plate 59b located at the left part 15 and a second connection plate 59a located at the right part 15 of the plate-like structure 12. The first and second connection plates 59b and 59a are dimensioned to match each other to make a smooth connection when the two connection plates are placed over each other. The connection plates 59a and 59b can be part of the right and left parts 14 and 15 of the plate-like structure 12, respectively. Since the right and left parts 14 and 15 of the plate-like structure 12 can be readily separated from each other, to wash the cooktop hygiene device the user removes the left and right parts of the plate-like structure 12 as separate pieces, each of which is small enough to carry and fit into a conventional dishwasher, and place each part into the dishwasher. Fig. 8b shows another modified cooktop hygiene device where the right and left parts 14 and 15 of the plate-like structure 12 are connected by a flexible piece of material 57. Suitable materials for the flexible piece of material 57 include elastomers such as silicone or nitrile rubber, plastic film or thin metal film. The flexible piece of material allows the folding of the plate-like structure 12 to fit into a conventional dishwasher. Figs. 9 and 9a show another modified version of the cooktop hygiene device 10 of Fig. 1. This modified cooktop hygiene device is best suited for gas ranges having a cooktop surface 93 (shown in dotted lines in Fig. 9). It comprises two rectangular drip pans 63, one on the left part 15 and the other on the right part 14 of the plate-like structure 12. Each rectangular drip pan 63 is positioned below two heaters 91 for receiving food and hquid spillings or sputterings from the cookwares or utensils supported on the cookware supports such as grates 95 (in dotted lines in both Figs. 9 and 9a). Each rectangular drip pan 63 comprises a bottom 61, two openings 24 formed on the bottom 61 for receiving the two heaters 91, and a side wall 62 for connecting the bottom 61 to plate-like structure 12. A raised peripheral wall 60 is formed around each opening 24 to prevent the solid and liquid spillings from falling out of the drip pan. It is appreciated that the cooktop hygiene device may comprise one drip pan, either square or circular depending on the configuration of the cooktop, for each heater 91. It is also appreciated that the cooktop hygiene device may comprise two or four heater covers 11 (not shown) for covering the heaters 91 and the cookware supports 95. Figs. 10 and 10a show another modified version of the cooktop hygiene device 10 of Fig. 1. This modified cooktop hygiene device is best suited for electric ranges having a cooktop surface 93 (shown in dotted lines in Fig. 10). It comprises four drip pans 63, two on the left part 15 and ' the other two on the right part 14 of the plate-like structure 12. Each drip pan 63 is positioned below a heater 91 for receiving the food and liquid spillings or sputterings from the cookwares or utensils on the heaters. Each drip pan 63 comprises a bottom 61, a side wall 62 for connecting the bottom 61 to plate-like structure 12, and an optional opening 24 having an inner wall 23 formed on the bottom 61. A raised wall 60 is formed around the opemng 24 to prevent the solid and liquid spillings from falling out of the drip pan. A ring-like structure 68 may be located around the upper end of the drip pan 63 for insulating the heater support 95 (shown in dotted lines in Figs. 10 and 10a) from the drip pan. A plurality of openings 68 are formed on the side wall 62 of each drip pan 63 so that at least one of the openings 68 will face the electrical socket 67 for the corresponding heater, thereby allowing the electrical plug (not shown) for the heater to pass this opening and plug into the socket. It is appreciated that the drip pans 63 can be used to replace the existing drip pans in a cooktop or be positioned above the existing drip pans. A rectangular opening 72 is formed on the plate-like structure 12 for receiving the control knobs 99 (shown in dotted lines in Figs. 10 and 10a) on the cooktop surface 93. A control panel cover 73 is connected to plate-like structure 12 with a hinge 74 for covering the control knobs. The control knob cover prevents food and liquid spillings or sputterings from contaminating the control knobs for the cooktop and possibly oven, thus reducing the need to clean the difficult to reach knobs. It is appreciated that the control knobs 99 for a cooktop or combined cooktop/oven range may be located on other location of the cooktop such as on the surface of a raised wall near the back of the cooktop or on the surface of the front wall. The plate-like structure 12 of the cooktop hygiene device 10 can be extended to cover part of or all the surface of the raised wall or the front wall of the cooktop and to allow the control knob cover 73 to cover the control knobs on such surface. The scope of the invention is obviously not restricted to the various embodiments described by way of examples and depicted in the drawings, there being numerous changes, modifications, combinations, additions, and applications thereof imaginable within the purview of the claims.

Claims: What is claimed is: 1. A cooktop hygiene device for use with a cooktop having a plurality of heaters, said cooktop hygiene device comprising a plate-like sttucture removably mountable onto the cooktop for preventing food and liquid spillings or sputterings from contaminating cooktop surface, said plate-like structure comprising: a first surface adapted to receive food and liquid spillings or sputterings from cookware or uteiisil during food preparation process; a second surface adapted to face the surface of the cooktop; and a plurality of openings located on said plate-like structure to allow the heaters of the cooktop to be accessible so that a user can place a cookware or utensil on or above a heater on the cooktop for heating the content in the cookware or utensil when the cooktop hygiene device is mounted to the cooktop. 2. A cooktop hygiene device as defined in claim 1 further comprising a fold facilitator for allowing the folding of said cooktop hygiene device to fit into a dishwasher. 3. A cooktop hygiene device as defined in claim 1 wherein said plate-like structure is adapted to be flexible and capable of being folded or rolled. 4. A cooktop hygiene device as defined in claim 1 wherein said plate-like structure comprises a plastic or elastomer film containing heavy inorganic fillers to reduce the formation of wrinkles or curls on said film. 5. A cooktop hygiene device as defined in claim 1 further comprising an anti-motion mechanism for preventing said cooktop hygiene device from movement on the cooktop. 6. A cooktop hygiene device as defined in claim 1 further comprising heater covers for said plurality of openings. 7. A cooktop hygiene device as defined in claim 6 further comprising a hinge for connecting said heater cover to said plate-like structure, said hinge including a extension for positioning said heater cover sufficiently away from the heater to prevent said heater cover from blocking the access to the heater. 8. A cooktop hygiene device as defined in claim 6 further comprising a lock mechanism for locking said heater covers to said plate-like structure to facilitate the handling and washing of said cooktop hygiene device. 9. A cooktop hygiene device as defined in claim 6 wherein said heater cover comprises a heat-conducting plate made of highly heat-resistant material for engaging with the heater on the cooktop and conducting heat from the heater to cookware or utensil on said heat-conducting plate. 10. A cooktop hygiene device as defined in claim 6 further comprising a heat restriction zone for connecting said heat-conducting plate to said plate-like structure. 11. A cooktop hygiene device as defined in claim 6 wherein said opening having a raised peripheral edge to prevent food and liquid spillings or sputterings from leaving said first surface. 12. In a cooktop such as an electric or gas range comprising a plurality of heaters for preparing food, a method for preventing the surface of the cooktop from being contaminated by food and liquid spillings or sputterings thereby reducing or even eliminating the need to clean the surface of the cooktop, said method comprising: mounting a cooktop hygiene device comprising a plate-like structure generally impermeable to the food and liquid spillings or sputterings onto the cooktop; collecting the food and liquid spillings or sputterings from cookware or utensils during food preparation process onto the upper surface of the plate-like structure; and removing the cooktop hygiene device from the cooktop for the purpose of washing or disposing the cooktop hygiene device after the user determines that there is too much food and liquid spillings or sputterings collected on the upper surface of the plate-like structure. 13. A method as defined in claim 12 further comprising a step of folding said plate- like structure so that said cooktop hygiene device can fit into a dishwasher. 14. A method as defined in claim 12 wherein said plate-like structure comprises a plurality of openings for the heaters on the cooktop and said mounting step comprises matching said openings to the heaters. 15. A method as defined in claim 12 wherein said plate-like structure comprising a plurality of cooking zones for engaging with the heaters and conducting heat from the heaters to the cookware or utensil on or above said cooking zones. 16. A cooktop hygiene device for use with a cooktop, said device comprising a platelike structure removably mountable to the cooktop for preventing food and liquid spillings or sputterings from contaminating cooktop surface, said plate-like structure comprising: a first plate-like member comprising a first surface for receiving food and liquid spillings or sputterings from cookware or utensil during food preparation process and a second surface adapted to face the surface of the cooktop; a second plate-like member comprising a first surface for receiving food and liquid spillings or sputterings from cookware or utensil during food preparation process and a second surface adapted to face the surface of the cooktop; and a connector for connecting said first plate-like member to said second plate-like member, said connector being adapted to enable a user to reduce the size of said cooktop hygiene device to fit into a dishwasher for cleaning said cooktop hygiene device. 17. A cooktop hygiene device as defined in claim 16 wherein said connector comprises a flexible or bendable material to allow a user to reduce the size of said cooktop hygiene device by folding said plate-like structure. 18. A cooktop hygiene device as defined in claim 16 wherein said connector comprises a hinge to allow a user to reduce the size of said cooktop hygiene device by folding said platelike structure. 19. A cooktop hygiene device as defined in claim 16 wherein said connector comprises a first connection member located on said first plate-like member and a second connection member located on said second plate-like member to interface with said first connection member to prevent the food or liquid spillings or sputterings from passing through said plate-like structure. 20. A cooktop hygiene device as defined in claim 16 wherein said connector comprises a first chamber to receive at least part of said first plate-like member and a second chamber to receive at least part of said second plate-like member. 21. A cooktop hygiene device as defined in claim 16 wherein said connector is adapted to allow a user to change the dimension of said cooktop hygiene device to fit the cooktop. 22. A cooktop hygiene device as defined in claim 16 wherein said connector comprises an expandable member such as a pleated member or an expandable material. 23. A cooktop hygiene device as defined in claim 16 wherein said plate-like structure further comprises a plurality of openings formed on said first and second plate-like members for receiving the heaters of the cooktop. 24. A cooktop hygiene device as defined in claim 23 further comprising a plurality of heater covers for said plurality of openings. 25. A cooktop hygiene device as defined in claim 16 further comprising a plurality of cooking zones on said plate-like structure for engaging with the heaters on the cooktop and conducting heat from the heaters to the cookware or utensil on or above said cooking zones. 26. A cooktop hygiene device as defined in claim 25 further comprising heat restriction zones located between said cooking zones and said plate-like member for preventing or limiting the heat flow from said cooking zones to said plate-like member. 27. A cooktop hygiene device as defined in claim 25 wherein said first and second plate-like members are anisotropic in heat conductivity so that the heat from the heaters on the cooktop are substantially confined within said cooking zones. 28. A cooktop hygiene device as defined in claim 25 further comprising a raised wall around at least one of said cooking zones to convert said at least one cooking zone into a cookware for cooking food. 29. A cooktop hygiene device as defined in claim 25 further comprising air vent for providing air to the heaters. 30. A cooktop hygiene device as defined in claim 25 wherein said cooking zone comprises raised or recessed structures for increasing the surface area thereby improving the heat transfer from said cooking zone to the surroundingv 31. A cooktop hygiene device for use with a cooktop having a plurality of heaters, said cooktop hygiene device being removably mountable to the cooktop and comprising a plate-like structure for preventing food and liquid spillings or sputterings from contaminating cooktop surface, said plate-like structure comprising: a first surface adapted to receive food and liquid spillings or sputterings from cookware or utensil during food preparation process; a second surface adapted to face the surface of the cooktop; and a flexible plate material such as a film, sheet, foil or cloth, said flexible plate material being sufficiently flexible to be folded or rolled thereby enabling said cooktop hygiene device to fit into a dishwasher or wash machine, said flexible plate material being generally impermeable to food and liquid spillings or sputterings collected on said first surface of said plate-like structure thereby preventing the food and liquid spillings or sputterings from contaminating cooktop surface. 32. A cooktop hygiene device as defined in claim 29 further comprising at least one elongated support member secured to said flexible plate material for facilitating the handling of said cooktop hygiene device. 33. A cooktop, hygiene device as defined in claim 29 wherein said plate-like structure further comprises a plurality of openings for receiving the heaters on the cooktop thereby allowing a user to place cookware or utensil on the heaters. 34. A cooktop hygiene device as defined in claim 31 further comprising heater covers for covering the heaters. 35. A cooktop hygiene device as defined in claim 32 further comprising a lock mechanism for locking said heater covers t said plate-like sttucture to facihtate the handling and washing of said cooktop hygiene device. 36. A cooktop hygiene device as defined in claim 29 further comprising cooking zones on said plate-like structure for engaging with the heaters on the cooktop and conducting heat from the heater to the cookware or utensil on said cooking zone. 37. A cooktop hygiene device as defined in claim 34 further comprising heat restriction zones surrounding said cooking zones for preventing or limiting the heat flow from said cooking zones to the other part of said cooktop hygiene device. 38. A cooktop hygiene device as defined in claim 29 wherein said flexible plate material is anisotropic in heat conductivity so that the heat from the heaters on the cooktop. are substantially confined within said cooking zones. 39. A cooktop hygiene device as defined in claim 29 wherein said flexible plate material comprises numerous solid pieces connected to each other by narrow connectors and separated from each other by air gaps, said narrow connectors being sufficiently narrow or thin to minimize the heat conduction between said solid pieces. 40. A cooktop hygiene device as defined in claim 37 wherein said air gaps are sufficiently small or filled with heat insulation materials, thereby preventing the food or liquid spillings or sputterings to be collected on said first surface from passing through. 41. A cooktop hygiene device as defined in claim 29 wherein said flexible plate material is a highly fluorinated polymer film such as a Teflon film. 42. A cooktop hygiene device as defined in claim 29 wherein said flexible plate material is a metal film such as a stainless steel or aluminum film or foil. 43. . A cooktop hygiene device as defined in claim 29 wherein said flexible plate material is a woven or non-woven cloth made of fibers such as thin stainless steel or glass fibers. 44. A cooktop hygiene device as defined in claim 29 wherein said woven or non- woven cloth comprises a coating such as a Teflon or elastomer coating. 45. A cooktop hygiene device as defined in claim 29 further comprising a fold facilitator for facilitating the folding of said plate-like structure. 46. A cooktop hygiene device as defined in claim 29 wherein said plate-like structure further comprises an expandable section to allow a user to change the dimension of said cooktop hygiene device to fit the cooktop. 47. A cooktop hygiene device as defined in claim 29 further comprising an anti- motion mechanism for preventing said cooktop hygiene device from movement on the cooktop. 48. A cooktop hygiene device as defined in claim 29 wherein said plate-like structure has approximately the same dimension as the cooktop surface and is adapted to fit the contour of the cooktop surface. 49. A cooktop hygiene device as defined in claim 29 wherein said flexible plate material comprises heavy inorganic fillers to reduce the formation of wrinkles or curls on said flexible plate material. 50. A cooktop hygiene device for use with a cooktop having a plurality of heaters, said cooktop hygiene device being mountable to the cooktop and comprising a plate-like structure for preventing food and liquid spillings or sputterings from contaminating cooktop surface, said plate-like structure comprising: a first surface adapted to receive food and liquid spillings or sputterings from cookware or utensil during food preparation process; a second surface adapted to face the surface of the cooktop; and a plate material adapted to allow the formation of a plurality of openings or partial openings on said plate-like structure by contacting said plate-like sttucture with the heaters on the cooktop and heating the sections of said plate-like structure that is directly above the heaters to a temperature high enough to cause said plate material in said sections to weaken, melt or degrade, said openings or partial openings formed on said plate-like structure enabling heat to transfer efficiently from the heaters to cookware or utensil at or above said openings. 51. A cooktop hygiene device as defined in claim 46 wherein said plate material is a highly fluorinated film such as a Teflon film. 52. A cooktop hygiene device as defined in claim 46 wherein said plate material is a metal film or foil such an aluminum foil. 53. A cooktop hygiene device as defined in claim 46 wherein said plate material is a non-flammable polymer film such as a non-flammable plastic or elastomer film. 54. A cooktop hygiene device as defined in claim 46 wherein said plate-like structure comprises a first layer made of said plate-like material and a second layer capable of mamtaining its integrity under the heat of the heaters on the cooktop, said openings being formed in said first layer. 55. A cooktop hygiene device as defined in claim 46 wherein said plate-like structure comprises a porous plate capable of mamtaining its integrity under the heat of the heaters on the cooktop and a coating made of said plate-like material. 56. A cooktop hygiene device as defined in claim 46 further comprising a fold facilitator for facilitating the folding of said plate-like structure. 57. A cooktop hygiene device as defined in claim 46 further comprising at least one elongated support member secured to said plate-like structure for facilitating the handling of said cooktop hygiene device. 58. A cooktop hygiene device for use with a cooktop having a plurality of heaters, said cooktop hygiene device comprising a plate-like structure removably mountable onto the cooktop for preventing food and liquid spillings or sputterings from contaminating cooktop surface, said plate-like structure comprising: a first plate-like structure comprising ah upper surface for receiving food and liquid spillings or sputterings from cookware or utensil during food preparation and a second surface adapted to face the surface of the cooktop, said first plate-like structure being configured to fit into a dishwasher and to be dishwasher washable; and a second plate-like structure comprising an upper surface for receiving food and liquid spillings or sputterings from cookware or utensil during food preparation and a second surface adapted to face the surface of the cooktop, said first plate-like structure being configured to fit into a dishwasher and to be dishwasher washable. 59. A cooktop hygiene device as defined in claim 56 wherein said plate-like structure further comprises a plurality of openings formed on said first and second plate-like structures for receiving the heaters of the cooktop. 60. A cooktop hygiene device as defined in claim 57 further comprising a plurality of heater covers for said plurality of openings. 61. A cooktop hygiene device as defined in claim 56 further comprising cooking zones on said plate-like structure for engaging with the heaters on the cooktop and conducting heat from the heaters to the cookware or utensil on or above said cooking zones and heat restriction zones located between said cooking zones and said plate-like member for preventing. or limiting the heat flow from said cooking zones to said plate-like member. 62. A cooktop hygiene device as defined in claim 56 further comprising a connector for connecting said first plate-like structure to said second plate-like structure, said connector being adapted to enable the folding or stacking of said first plate-like structure over said second plate-like structure thereby enabling the cooktop hygiene device to fit into the dishwasher. 63. A cooktop hygiene device as defined in claim 56 wherein said connector comprises a first connection member located on said first plate-like structure and a second connection member located on said second plate-like structure and to interface with said first connection structure to prevent the food or liquid spillings or sputterings from passing through said plate-like structure. 64. A cooktop hygiene device as defined in claim 56 wherein said connector comprises a first chamber to receive at least part of said first plate-like structure and a second chamber to receive at least part of said second connection chamber. 65. A cooktop hygiene device for use with a cooktop such as an electric or gas range, said. cooktop hygiene device being adapted to be removably mountable to the cooktop and comprising a plate-like structure for protecting cooktop surface from food and liquid spillings or sputterings, said a plate-like structure comprising: a first surface adapted to collect the food and liquid spillings or sputterings from cookware or utensil during food preparation process; a second surface adapted to face the surface of the cooktop; and a non-flammable material generally impermeable to the food and liquid spillings or sputterings collected on said first surface thereby preventing the food and liquid spillings or sputterings from contaminating the surface of the cooktop. 66. A cooktop hygiene device as defined in claim 29 wherein said plate-like structure is adapted to be anisotropic in heat conductivity to prevent heat conduction along the surface of said platelike structure thereby maintaining at least part of said plate-like sttucture substantially cool to touch when the cooktop is in use. 67. A cooktop hygiene device as defined in claim 29 further comprising a fold facilitator for facilitating the folding of said plate-like structure. 68. A cooktop hygiene device as defined in claim 29 wherein said plate-like structure further comprises an expandable section to allow a user to change the dimension of said cooktop hygiene device to fit the cooktop. 69. A cooktop hygiene device as defined in claim 29 further comprising an anti- motion mechanism for preventing said cooktop hygiene device from movement on the cooktop. 70. A cooktop hygiene device as defined in claim 65 further comprising at least one elongated support member secured to said plate-like structure for facilitating the handling of said cooktop hygiene device. 71. A cooktop hygiene device as defined in claim 65 wherein said plate-like structure further comprises a plurality of openings for receiving the heaters on the cooktop thereby allowing a user to place cookware or utensil on the heaters. 72. A cooktop hygiene device as defined in claim 67 further comprising heater covers for covering said openings. 73. A cooktop hygiene device as defined in claim 29 further comprising cooking zones on said plate-like structure for engaging with the heaters on the cooktop and conducting heat from the heater to the cookware or utensil on said cooking zone and heat restriction zones surrounding said cooking zones for preventing or limiting the heat flow from said cooking zones to the other part of said cooktop hygiene device. 74. At least one cooktop hygiene device for use with a cooktop in a package, said cooktop hygiene device comprising a flexible plate-like structure capable of being rolled on itself or on a core for facilitating storage or transportation of said device, said flexible plate-like structure comprising a . first surface adapted to collect food and liquid spillings or sputterings from cookware or utensil during food preparation process and a second surface adapted to face cooktop surface, said flexible plate-like structure being adapted to be generally impermeable to the food and liquid spillings or sputterings collected on said first surface thereby preventing the food and liquid spillings or sputterings from contaminating cooktop surface. 75. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 further comprising a breakable material for connecting another similar or identical cooktop hygiene device in said package to said cooktop hygiene device. 76. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 further comprising a mark such as a printed, pressed or perforated, line for dividing two adjacent cooktop hygiene devices in said package. 77. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74, said package comprising at least one additional similar or identical cooktop hygiene device rolled on or over said at least one cooktop hygiene device. 78. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74, said at least one cooktop hygiene device further comprising an anti-motion mechanism for preventing said cooktop hygiene device from movement on the cooktop. 79., At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 wherein said flexible plate-like sttucture comprises heavy inorganic fillers to reduce or prevent the formation of wrinkle or curl on said flexible plate-like structure. 80. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 wherein said at least one cooktop hygiene device further comprises at least one elongated support member secured to said flexible plate-like structure for facilitating the handling of said cooktop hygiene device. 81. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 wherein said flexible plate-like structure further comprises a plurality of openings for receiving the heaters on the cooktop thereby allowing a user to place cookware or utensil on or above the heaters. 82. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 further comprising heater covers for covering said openings. 83. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 wherein said flexible plate-like structure is adapted to have approximately the same dimension as the upper surface of the cooktop. 84. At least one cooktop hygiene device for use with a cooktop in a package as defined in claim 74 further comprising cooking zones on said flexible plate-like structure for engaging with the heaters on the cooktop and conducting heat from the heater to the cookware or utensil on said cooking zone. 85. A cooktop hygiene device for use with a cooktop having a plurality of heaters for maintaining the cooktop in a clean or hygienic condition, said device being removably mountable to the cooktop and comprising: a plate-like structure having a first surface for receiving the food and liquid spillings or sputterings from cookware or utensil during food preparation process and a second surface adapted to face the surface of the cooktop, said plate-like structure being generally impermeable to the food and liquid spillings or sputterings collected on said first surface thereby preventing the food and liquid spillings or sputterings from contaminating cooktop surface; and a plurality of cooking zones on said plate-like structure for engaging with the heaters on the cooktop and for conducting heat from the heaters to cookware or ύtensil on or above said cooking zones. 86. A cooktop hygiene device as defined in claim 85 further comprising heat restriction zones surrounding said cooking zones for preventing or limiting the heat flow from said cooking zones to the other part of said cooktop hygiene device. 87. A cooktop hygiene device as defined in claim 85 wherein said plate-like structure is adapted to be anisotropic in heat conductivity so that the heat from the heaters on the cooktop are substantially confined within said cooking zones. 88. A cooktop hygiene device as defined in claim 85 wherein said plate-like structure comprises numerous solid pieces connected to each other by narrow connectors and separated from each other by air gaps, said narrow connectors being sufficiently narrow or thin to minimize the heat conduction between said solid pieces thereby preventing or limiting the heat conduction along the surface of said cooking zones and said plate-like structure. 89. A cooktop hygiene device as defined in claim 88 wherein said air gaps are sufficiently small or filled with heat insulation materials, thereby preventing the food or liquid spillings or sputterings to be collected on said first surface from passing through. 90. A cooktop hygiene device as defined in claim 85 further comprising a raised wall around at least one of said cooking zones to convert said at least one cooking zone into a cookware for cooking food. 91. A cooktop hygiene device as defined in claim 85 further comprising air vent for providing air to the heaters. 92. A cooktop hygiene device as defined in claim 85 wherein said cooking zone comprises raised or recessed structures for increasing the surface area thereby improving the heat transfer from said cooking zone to the surrounding. 93. A cooktop hygiene device as defined in claim 85 wherein said plate-like structure comprises a flexible plate such as a metal film of stainless steel or aluminum or a woven or non-woven cloth made of fibers such as stainless steel or glass fibers. 94. A cooktop hygiene device as defined in claim 85 further comprising a coating such as a Teflon, elastomer, glass or ceramic coating for at least the surface of said cooking zones of said cooktop hygiene device. 95. A cooktop hygiene device as defined in claim 85 further comprising a fold facilitator for facilitating the folding of said plate-like structure. 96. A cooktop hygiene device as defined in claim 85 wherein said plate-like structure further comprises an expandable section to allow a user to change the dimension of said cooktop hygiene device to fit the cooktop. 97. A cooktop hygiene device as defined in claim 85 further comprising an anti- motion mechanism for preventing said cooktop hygiene device from movement on the cooktop. 98. A cooktop hygiene device for use with a cooktop having a plurality of heaters for maintaining the cooktop in a clean or hygienic condition, said device being removably mountable to the cooktop and comprising: a plate-like structure having a first surface for receiving food and liquid spillings or sputterings from cookware or utensil during food preparation process and a second surface adapted to face the surface of the cooktop, said plate-like structure being generally impermeable to the food and liquid spillings or sputterings collected on said first surface thereby preventing the food and liquid spillings or sputterings from contaminating cooktop surface; and a plurality of drip pans secured to said plate-like sttucture, said drip pans being adapted to be positioned below the heaters of the cooktop for catching food and liquid spillings or sputterings from cookware or utensil during food preparation process. 99. A cooktop hygiene device as defined in claim 98 . further comprising a fold facilitator for facihtating the folding of said plate-like structure. 100. A cooktop hygiene device as defined in claim 98 wherein said drip pan comprises an opening for receiving the heaters on the cooktop. 101. A cooktop hygiene device as defined in claim 100 wherein said opening on said drip pan is adapted to prevent the food and liquid spillings or sputterings received by said drip pan from flowing out of said drip pan. 102. A cooktop hygiene device as defined in claim 100 wherein said drip pan comprises a plurality of openings for the electrical leads or plug of the heater if the heater is energized by electricity, said plurality of openings being adapted to ensure the electrical socket for the heater is accessible to the electrical leads or plug. 103. A cooktop hygiene device as defined in claim 85 wherein said plate-like structure further comprises an expandable section to allow a user to change the dimension of said cooktop hygiene device to fit the cooktop. 104. A cooktop hygiene device as defined in claim 98 further comprising heater covers for the heaters. 105. A cooktop hygiene device as defined in claim 98 further comprising a hinge for connecting said heater cover to said plate-like sttucture, said hinge including an extension for positioning said heater cover sufficiently away from the heater to prevent said heater cover from blocking the heater. 106. A cooktop hygiene device as defined in claim 98 further comprising a lock mechanism for locking said heater covers to said plate-like structure to facilitate the handling and washing of said cooktop hygiene device. 107. A cooktop hygiene device as defined in claim 98 further comprising an opening on said plate like structure for receiving the control knobs of the cooktop and a control knob cover for covering said opening for the control knobs. 108. A hygienic cooktop system in which the cooktop can be maintained in a clean or hygienic condition, said hygienic cooktop system comprising: a cooktop surface; a plurality of electric or gas heaters on said cooktop surface; and a cooktop hygiene device adapted to be removably mountable to said cooktop, said cooktop hygiene device comprising a plate-like structure having a first surface for receiving food and liquid spillings or sputterings from cookware or utensil during food preparation process and a second surface adapted to face the surface of the cooktop, said plate-like structure being generally impermeable to the food and liquid spillings or sputterings collected on said first surface thereby preventing the food and liquid spillings or sputterings from contaminating cooktop surface. 109. A hygienic cooktop system as defined in claim 108 further comprising a fold facilitator for facilitating the folding of said plate-like structure thereby enabling said cooktop hygiene device to fit into a dishwasher. 110. A hygienic cooktop system as defined in claim 108 wherein said plate-like structure comprises a first plate-like member, a second plate-like member and a connector for connecting said first and second plate-like member. 111. A hygienic cooktop system as defined in claim 108 wherein said connector comprises a first connection member located on said first plate-like member and a second connection member located on said second plate-like member to interface with said first connection member to prevent the food or liquid spillings or sputterings from passing through said plate-like structure. 112. A hygienic cooktop system as defined in claim 108 wherein said connector comprises a first chamber to receive at least part of said first plate-like member and a second chamber to receive at least part of said second connection member. 113. A hygienic cooktop system as defined in claim 108 wherein said cooktop hygiene device further comprises a plurality of openings for receiving said heaters on said cooktop surface. 114. A hygienic cooktop system as defined in claim 108 further comprising heater covers for said heaters. 115. A hygienic cooktop system as. defined in claim 108 further comprising hinges for connecting said heater covers to said plate-like structure. 116. A hygienic cooktop system as defined in claim 108 wherein said hinge includes an extension for positioning said heater cover sufficiently away from the heater to prevent said heater cover from interfering with access to the heater. 117. A hygienic cooktop system as defined in claim 108 wherein said cooktop hygiene device further comprises a plurality of drip pans secured to said plate-like structure, said drip pans being adapted to be positioned below said electric or gas heaters of said cooktop for catching food and liquid spillings or sputterings from cookware or utensil during food preparation process.

Inventors: CAI EDWARD Z, CAI, EDWARD, Z.
Applicants: CAI EDWARD Z, CAI, EDWARD, Z.
Application year: 2001
Main classification: H05B3
IPC codes: F24C15