1 KETTLE AND BASE FIELD [0001] The invention pertains to cordless kettles and more particularly to a cordless kettle with various temperature settings and other enhancements. BACKGROUND [0002] Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of the common general knowledge in the field. [0003] A conventional electric kettle, once activated by a user, will boil its contents and then cease operation. However, the growing popularity of tea brewing and sophistication of its Western consumers indicates a need for a kettle that is adapted to deliver water at a variety of distinct temperatures, including boiling. [0004] The western tea drinking consumer is also desirous of acquiring a kitchen appliance with enhanced aesthetic and performance features. [0005] Data communication between the base and cordless kettle are disclosed in the applicant's co-pending PCT Application No. PCT/AU2008/000724 incorporated here by reference. Construction of a kettle with lid damper is disclosed in the applicant's Australian Provisional Application No. 2004902070, incorporated here by reference. [0006] The present invention provides improvements that contribute to the aesthetic, ergonomic and functional attributes of a kettle or other device that generates hot water or steam. OBJECT [0007] It is an object of the present invention to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.
2 [0008] It is an object of the invention in its preferred form to provide combination of cordless kettle and base, wherein the device has a plurality of selectable temperature settings each defined by a separate one of the discrete control switches. SUMMARY [0009] There is disclosed herein a device for heating a volume of water that it contains, being a combination of a base and a cordless kettle, the kettle having a heating element and adapted to be mounted on the base, the base having within it a power supply and a processor for responding to information originating from the kettle, the processor adapted to respond to user inputs and to effect power control over the heating element, wherein: the base has a plurality of discrete control buttons and an on/off switch, each of the discrete control buttons being operatively associated with a respective individual pre-determined fixed temperature selection, such that input from a selected one of the discrete control buttons and then subsequently a second input from the on/off switch causes the power to be supplied to the heating element in the kettle for heating the water to the pre-determined fixed temperature associated with the said selected one of the discrete control buttons. [0010] Preferably, the switch is a button. [0011] Preferably, the discrete control buttons are arranged in a row, with the fixed temperatures increasing along the row, and one of the discrete control buttons corresponding to a fixed temperature of about 100 0 C. [0012] Preferably, the discrete control buttons include a keep warm button that causes operation of the device so that the water is maintained at about the fixed temperature associated with a last selected one of the temperature control buttons, the keep warm button being located at an end of the row. [0013] Preferably, the row includes five of said discrete control buttons and the keep warm button, with the five discrete control buttons providing the fixed temperatures.
3 BRIEF DESCRIPTION OF THE DRAWING FIGURES [0014] In order that the invention be better understood, reference is now made to the following drawing figures in which: [0015] FIG. 1 is a perspective view of a cordless kettle and base in accordance with the teachings of the present invention; [0016] FIG. 2 is a plan view of kettle base and control; [0017] FIG. 3 is a perspective view of underside of kettle lid; [0018] FIG. 4 is a cross section view of kettle lid; [0019] FIG. 5 is a perspective view of kettle vessel showing filter in situation; [0020] FIG. 6 is a perspective view of pour filter; [0021] FIG. 7 is an underside view of kettle base and element; [0022] FIG. 8 is a cross section view of a vessel body; [0023] FIG. 9 is a cross sectional diagram of a semi-automatic tea maker showing the tea brewing chamber and tea plunger; [0024] FIG. 10 is a cross section of the device depicted in Figure 9, wherein the chamber is partially inserted and wherein the tea brewing process has not yet been initiated; [0025] FIG. 11 is another cross sectional view of a semi-automatic tea maker made in accordance with the teachings of the present invention. Details of this drawing figure illustrate two embodiments of a brewing chamber sensor as well as the user controls; [0026] FIG. 12 is a cross section of a semi-automatic team maker illustrating the completion of the tea brewing process; [0027] FIG. 13 illustrates alternate embodiments of the invention, in cross section; and 4 [0028] FIG. 14 are partial cross sections showing the operation of an alternate plunger style. BEST MODE AND OTHER EMBODIMENTS [0029] As shown in FIG. 1, a cordless kettle 10 has a base 11. The base 11 is connectable to a mains power outlet and operates, when the kettle and base are attached to one another, to control the operation of the kettle and provide the user with convenient controls and feedback concerning the operation of the kettle. Data communication between the base and cordless kettle are disclosed in the applicant's co-pending PCT Application No. PCT/AU2008/000724 incorporated here by reference. Construction of a kettle with lid damper is disclosed in the applicant's Australian Provisional Application No. 2004902070, incorporated here by reference. [0030] In the example of FIG. 1, the kettle 10 further comprises a hinged and transparent lid 12 that is operated by a thumb button 13 located on an upper extent of the kettle's handle 14. The kettle has a pouring spout 15 and a transparent view window 16. As will be explained, the interior of the kettle is illuminated and light (such as coloured light) is visible both through the view window 16 and the transparent lid 12. [0031] As shown in FIG. 2, an upper surface 20 of the base 1 presents the user with a variety of buttons, switches or controls 21. A multi-pole electrical coupling 22 connects with a cooperating coupling located on an underside of the kettle 10. The coupling 22 transmits power and optionally, control signals to the kettle and may optionally receive data communication signals from the kettle, for example regarding the temperature of the water in the kettle. In this example, the temperature related user controls are five in number. Each control in this example comprises a button that is surrounded by a selectively illuminated ring 24. Any other visual indicator or display may be used in place of the illuminated ring 24. From left to right, of the row of fixed temperature control buttons, with respect to FIG. 2, includes a first user control 23 is marked e.g. "green tea" and corresponds with a final water temperature of 80 degrees Celsius ("'C"). A second user control is marked "white tea" and is also marked with a final water temperature of 85 0 C. A third button is marked "oolong" and is marked with a final water temperature of 90'C. A fourth user control is marked "coffee" and with a final water temperature of 95 0 C. A fifth user control is marked "boil/black tea" and is marked with a final water temperature of 100'C. Selection or activation of any of the aforementioned temperature controls will cause the device's processor to select a water heating cycle. In addition to the five 5 temperature controls, the base is also provided with a start/cancel control 25. The start/ cancel control also has an illuminated ring 26 or other graphic indicator. As best see in Figure 2, the buttons are arranged in a row, with the temperature associated with the button increasing along the row. [0032] As previously mentioned, the heating cycle begins with a user selection that is first input through the temperature controls 24. Subsequent depression of the start/cancel control25 results in power being supplied to the kettle's heating coil and a simultaneous illumination of the indicator ring 26 (or other graphic indicator) associated with the start/ cancel control 25. After a use of the start/cancel control25, the water in the kettle will be heated to the user selected temperature whereupon the kettle's thermostatic control will provide feedback that causes a disabling of the kettle's heating element. This may be done, for example, by having the kettle's internal thermostat in communication with a processor located in the base 11. A subsequent user activation of the start/cancel control 25 during a heating cycle will cause the cycle to be terminated. Ergonomically, it is preferred that the inception and the cancellation of a heating cycle be conducted from the same user control 25 rather than, for example, having the user input a cancellation through one of the five individual temperature control buttons 28. In addition to the aforementioned controls, the base of the kettle also provides a "keep warm" button 27 that, if used during a heating cycle, will cause the device's processor to cooperate with the power supply and heating element to maintain the water in the kettle at either the last selected temperature for a set time, such as 20 minutes. [0033] In preferred embodiments, the illuminated ring 26 or other graphic indicator associated with the start/ cancel button 25 preferably changes colour so that it is a different colour (such as red) during a heating cycle that at any other time, a green ring 26 indicating that the unit is plugged in. This provides additional feedback to the user regarding which button to press when a cancellation of a cycle is required. In preferred embodiments, the rings 24 of the temperature selection controls are not illuminated until a selection has been made. Thus, the user knows what temperature has been selected because only that button's ring 24 or indicator is illuminated. It is also preferred that a user can re-select or change the final water temperature without use of the start/cancel control 25, simply by operating a different temperature control 23 to the one previously selected. In selected embodiments, the device will default to the last temperature selected so that if a particular temperature is regularly used, the user or operator need only activate the start/ cancel control 25. When this is done, the last selected temperature will be 6 indicated by the illumination of its ring 24 or other graphic indicator. The illumination ring 24 or other graphic indicator associated with a temperature selection control 23 may flash to indicate that the kettle is in a heating cycle. When the selected temperature is reached, the illumination ring 24 or other graphic device associated with a temperature control 23 is lit continuously (not flashing). The appropriate illumination ring 24 or other graphic device will stay in this continuous illumination mode for a predetermined amount of time, for example, one minute. [0034] As shown in FIG. 3, the kettle's lid 30 comprises an annular or ring-shaped frame 3 having a hinge component 32 for attaching the lid to the kettle's body. As shown in FIG. 4, the lid 30 is characterised by an upper lens 41 and a lower lens 42. This provides a large clear window that is cool to the touch. In this example, the lenses are lightly tinted and curved or domed away from the interior of the kettle. The curvature of the upper and lower lenses is similar. The upper lens 41 is generally flush with the surrounding portion of the frame. To combat condensation, the upper lens may be provided with a small vent 45 or one-way or check valve 46 leading into the interior space 43. The vent 45 is preferably small enough that capillary forces resist the inflow of liquids into the interior space 43. The lower lens 42 may also be flush with the lower surface of the frame 31. In preferred embodiments, the void or interior space 43 between the upper and lower lenses 41, 42 may be filled with an inert gas or dehumidified air so that the interior may be kept dry and free from condensation. In the example depicted in FIG. 4, the internal periphery of the void 43 further comprises a ring-like liner 44- The inside surface of the liner 44 is formed as a series of concentric, ascending steps. Light reflecting from the individual steps creates an aesthetically pleasing illusion of depth and serves as a means of indicating that the device is plugged in, by better reflecting the kettle's internal illumination through the upper lens 41. [0035] As shown in FIG. 5, water being poured through the kettle's spout 15 first passes through a pour filter 51. As with prior art pour filter's, the filter covers, from the inside of the kettle, the entirety of the pour opening 52. However, unlike other electric full size kettles the pour screen 5 1is not blocked or occluded by the conventional kind of bracing that is used to support the pour filter. As shown in FIG. 6, the pour filter 51 is continuous and unobstructed and supported only about its periphery 61 by a moulded polymeric frame 62 having no cross pieces or bracing that would obstruct the pour opening 52. In preferred embodiments, the pour filter 51 is a thin perforated metal screen. The polymeric frame 62 may include a finger grip portion 63 that 7 extends away from the filter 51, making it easier for the user to remove and reinsert the filter, as required. Thus, the filter 51 is considered unobstructed. [0036] As show in FIG. 7, a heating element 70 is located adjacent to the floor 71 of the internal fluid compartment of the kettle 10. The bare ends of the heating element 70 comprise cold pins 72, 73. The cold pins are the least hot portions of the element 70. The floor 71 also supports an LED illuminator 74 that is able to transmit light into the reservoir or internal compartment of the kettle through a transparent (or translucent) cover. To minimise heat damage and degradation to the LED illuminator 74, it is located adjacent to the cold pins 72, 73 and preferably equally spaced from each of the cold pins 72, 73. [0037] As shown in FIG. 8, the lower extremity 80 of the one piece metallic kettle body 81is strengthened by providing a continuous and smoothly radiused corner 82 that extends between the side wall 83 of the kettle body and a generally flat underside 84. The radiused continuity between the side wall 83 and the underside 84 can be achieved, for example, by roll forming the body's metal structure in the area of the lower extremity 80. In preferred embodiments, the underside 84 is stepped to receive a polymeric disk-like insert 85 that incorporates the feet 86 upon which the kettle rests. [0038] A semi-automatic tea maker 10 is depicted in Figure 9. As shown in that illustration, the tea maker 10 comprises a vessel 211, a tea brewing chamber 212 and the chamber's plunger 213. The tea maker may be used with a cordless base platform have the appropriate coupling arrangement to support the operation of the maker 210. [0039] The vessel 211 further comprises a water reservoir 112, a handle 213 and a pouring spout 214. The reservoir 112 is located above a base cavity 215. The base cavity 215 contains a heating element, a coupling (not shown) so that the vessel can be used in conjunction with a cordless base and, in preferred embodiments, a detector or sensor that responds when tea brewing chamber 212 is properly located adjacent to or against the floor 216 of the reservoir 112 (see Figure 11). It will be appreciated that electronic control over and user interface for the various functions required for the successful operation of the semi-automatic tea maker 10 may be contained in the base platform (see Figures 10 and 11) and the power and data are exchanged between the vessel and the base platform as required. In the alternative, the electronic controls may also be located in the base cavity 215 or even in the maker's hollow handle.
8 [0040] The vessel 11 further comprises a lid 223 having a (e.g.) central opening 224 for receiving the tea brewing chamber 212. The opening 224 further comprises a cylindrical sleeve, the upper extent of which is defined, for example, by an elastomeric ring or bead 225. Other sleeve shapes may be used. [0041] As shown in Figure 9, the tea brewing chamber 212 comprises, in this example, an open ended cylindrical body having a mouth opening 217 and an impermeable floor 218. The mouth 217 is surrounded by a rim 222. A small step 219 divides the chamber 212 into an upper portion 220 and a lower portion 221. The upper portion is not perforated whereas the lower portion 221 is perforated (except for the floor 218). In preferred embodiments, the diameter of the lower portion 221 is slightly less than the diameter of the upper portion 220. As further illustrated in Figure 9, the plunger 213 comprises a shaft 226 that extends between a knob 227 and a bell 228. The bell 228 is impermeable but for the open mouth 229, preferably encircled by an elastomeric seal 230. The shaft 226 is surrounded by a cap 231. In preferred embodiments, the cap has central depression 232 that allows for easy withdrawal of the knob 227 when the shaft 226 is fully depressed. The perimeter 233 of the cap fits within the mouth 217 of the tea brewing chamber 212. The perimeter 233 may be provide with a elastomeric seal 234 to improve the quality of the interface between the cap 231 and the chamber 212. [0042] Figure 9 also illustrates that loose tea 235 is placed by the user into the chamber 212 whereas water 236 is placed into the reservoir 112. [0043] As shown in Figure 10, tea leaves 235 are suspended above the water level 237 of the reservoir 112. This is facilitated by providing easy sliding fit or gap between the lower portion 221 of the tea brewing chamber 212 and the central opening of the vessel. When the chamber 212 is inserted into the opening, it will essentially descend and come to rest in the position illustrated owing to tactile feedback provided by the step. The larger diameter of the upper portion 220 (above the step 219) prevents the chamber from descending any further unless it is urged or pushed by the user. The bell 228 of the plunger 213 will easily descend until it contacts the step 219 where it will slightly resist, providing tactile feedback, then descending further into the lower portion 221 when pushed by the user using the knob 227. As illustrated, the user can then program the unit's controller or interface with the desired brewing temperature of the water in the vessel by pressing one of a variety of e.g. discrete temperature selection and indicating buttons or, or for example, dialling a temperature selection knob. In this illustration, 9 four discrete buttons 240 are provided. Pressing one of these buttons 240 will cause the temperature of the water in the reservoir 212 to rise to the set brew temperature being, for example, 175, 185, 195 or 212F. Thermostatic (e.g. thermistor) control over the water temperature prevents the water in the reservoir 212 from exceeding the brew temperature. In this example, two alerts or indicator lights 241, 242 are provided. The first indicator light 241 is illuminated by the electronic controller when the water in the reservoir 212 reaches the user set brewing temperature. The second indicator light 242 alerts the user when the brew duration, also set by the user, is reached. The user sets the brew duration with a single push button 243. Pushing the button 243 repeatedly changes the device's internal timer in, for example, one minute intervals of brew time. An illuminated countdown indicator or other alert or feedback device 244 shows the user how many minutes of brew time they have selected. In this example, brew times are set with the use of the button 243 in one minute increments ranging from 1-6 minutes. In addition to the six settings, a seventh setting caused by a further press of the button 243 causes the brew time to have an essentially infinite value, that is, the indicator 243 that indicates the end of the brew time will not function, regardless of the time duration after the inception of the brew period. If the user wants to simply use the vessel to heat water, a separate button 245 alters the programming so that brew time need not be inputted by the user. When the heat water control is activated, the user need only use the temperature control input 240 to set the desired thermostatically controlled temperature. Similarly, a "keep warm" button 246 allows single, preferably illuminated button to both allow the user to command the vessel to maintain a warm brew and to indicate when the vessel is operating in a "keep warm" mode. [0044] As shown in Figure 11, once the water in the reservoir 112 reaches the pre-established brew temperature, the appropriate alert or indicator 241 lets the user know that it is appropriate to lower the tea brewing chamber 212 fully into the reservoir by pressing it against the marginal resistance offered by the elastomeric ring or bead 225 of the central opening 224 of the vessel 211. In preferred embodiments, the base cavity 215 contains a sensor or detector that can determine when the tea brewing chamber 212 has been fully inserted into the reservoir 112. As shown in detail "A" of Figure 11, a reed switch arrangement 250 located below the floor 216 of the reservoir 112 can detect a magnet 251 embedded somewhere in or adjacent to the base 218 of the tea brewing chamber 212. Detail "B" of Figure 11 illustrates that the detection of the tea brewing chamber 212 can also be accomplished with a pressure sensitive micro switch or sensor 252 located beneath a flexible membrane or seal 253. Utilising either mechanism, the presence of the tea brewing chamber 212 in its lowest position will cause a signal to be sent to the 10 cooperating microprocessor or electronic controller so that the controller's timer can begin to count down the brew duration that was pre-set by the user. The countdown of the brew duration can be illustrated to the user by the display 244. Note that during the duration of the brewing process, the plunger's bell 228 is preferably located above the water level 237 and that the water in the reservoir 112 is free to enter and flow through the perforated lower portion 221 of the chamber 212. Brewing continues in this way for the duration pre-established by the user. [0045] At the end of the pre-established brewing time, a visual alarm indication 242 (or an audible one) alerts the user that the pre-established brewing time is completed and that the user should terminate the brewing process by fully lowering the plunger 213. As shown in Figure 12, the user has fully depressed the plunger 213. This causes the bell 228 to isolate the tea within it from the remainder of the reservoir. Because both the bell 228 and the floor 218 of the chamber 212 are impervious to water flow, further infusion of the water outside of the bell is essentially terminated. At this point, the thermostat, heating element and electronic controller cooperate to maintain the water in the reservoir at a warm or drinking temperature when the vessel is on its base. The vessel may be removed from its base for pouring. [0046] As was discussed with reference to Figure 11, the insertion of the tea brewing chamber 212 is detected by sensors located adjacent to or below the floor 216 of the reservoir 112. In order to isolate the sensors or detectors 250, 252 from the heat produced by the heating element, the sensors or detectors may be located in the lid. As shown in Figure 13A, a contact switch 255 may be located adjacent to the upper perimeter of the central opening 256 of the vessel 211. Thus, lowering of the tea brewing chamber 212 causes the chamber's rim 257 to activate the switch, sensor or detector 255. Another embodiment is depicted in Figure 13B. In this embodiment, a non-contact sensor such as a reed switch 258 is activated by the proximity of a small magnet 259 embedded in the rim 257 of the tea brewing chamber 212. The signals are transmitted by wires located in the body or handle of the vessel to the controller located, for example, in the base cavity 215. [0047] An alternate style of plunger is depicted in Figure 14. In this example, a lower extent 270 of the tea brewing chamber 212 lacks perforations. As previously disclosed, the floor 271 of the tea brewing chamber also lacks perforations. A flat, plunger 272 is used in place of a bell shaped plunger. When the flat plunger 272 is fully depressed, tea leaves are trapped between the plunger, the side wall 270 and the floor 271 isolating the contents of the lower extent from 11 the remainder of the reservoir and thus brewing ceases. [0048] While the present invention has been disclosed with reference to particular details of construction, these should be understood as having been provided by way of example and not as limitations to the scope or spirit of the invention.