This invention relates generally to temperature measuring devices, and more particularly, to a thermometer system for taking temperature measurements at differing locations.
The prior art is familiar with meat thermometers of the type that include a probe inserted into meat to determine internal cooking temperature. By way of example, the following patents, each incorporated herein by reference, exemplify various prior art meat thermometers: U.S. Pat. Nos. 6,230,649; 4,547,643; 4,475,024; 4,201,968; 4,122,322; 4,058,013; 3,991,615; and 3,975,720.
The prior art is also familiar with solid-state ovens that include controls for setting oven temperature, with basic clock timing and the like. For example, the following patents are incorporated herein by reference and provide useful background to such ovens: U.S. Pat. Nos. 4,054,778; 3,800,123; and 3,521,030.
There is a need for improved temperature control of ovens and cooking thermometers to improve safety and delivery of prepared food. Certain bacteria and disease-related anomalies may survive cooking within an oven of the prior art because a user cannot properly monitor food doneness. In conventional temperature probes, for example, one may measure meat temperature at a selected point, but fail to notice undercooked portions. Conversely, over-cooking can also occur because of inadequate temperature monitoring. The actual oven inside air temperature may be too high and can thus burn the outer layer of the cooking food; conversely, if the oven air temperature is too low, it may not cook the food to desired doneness within the original cooking time. Temperature control options associated with current solid-state ovens also do not address such food preparation issues: specifically, stated temperature readings do not adequately link to actual food doneness and temperature.
It is, accordingly, a feature of the invention to provide a thermometer that determines simultaneously the temperature of food placed within an oven and the oven air temperature. It is another feature of the present invention to provide the thermometer with sensors for measuring each of the food and oven air temperature. It is yet another feature of the present invention to provide a communications cable to transfer signals from the temperature sensors to electronics external to the oven for processing of the signals and display of temperature values. It is still another feature of the present invention to provide such a thermometer with timing and processing food doneness options for ensuring proper food preparation within the oven. It is still another feature of the present invention to provide such a thermometer that can quickly measure temperature values, is easy to operate, and particularly well suited for the proposed usages thereof.
In one aspect, the invention provides an elongated probe connected with a flexible electronic cable. The probe houses two temperature sensors—one for sensing internal food temperature, one for sensing inside oven air temperature. The sensors are spaced apart within the probe such that the one sensor can be positioned substantially within a food item and the other sensor can be positioned substantially outside of the food item and within the oven. Signals from the sensors are relayed from the probe and through the cable; external electronics may attach to the cable to acquire the signals and display associated temperatures.
In another aspect, the invention utilizes wireless transmission of sensor signals. The invention provides an elongated metal probe connected with a flexible electronic cable. The probe houses two temperature sensors—one for sensing internal food temperature, one for sensing inside oven air temperature. Signals from the sensors are relayed from the probe and through the cable to a first wireless termination. The first wireless termination wirelessly relays signals from the probe to a second wireless termination coupled to module electronics, to acquire the wireless signals and to display associated temperatures.
In operation, the probe is inserted into food within an operating oven, such that one of the sensors senses food temperature and such that the other of the sensors senses oven air temperature; the cable extends from the probe and through the door of the oven; the first wireless termination connects with the cable and resides external to the oven; the first wireless termination relays signals from the probe to the second wireless termination, coupled to the module electronics; the module electronics may be attached to a convenient location in the kitchen, usually near to the oven, to display temperatures from the probe.
The invention thus has certain advantages by accurately measuring food temperatures, and also quickly indicating actual oven inside air temperature. Specifically, with the invention, a user may monitor air and food internal temperatures during cooking to achieve the desired food doneness while avoiding over- or under-cooking of the food.
Other advantages and components of the invention are apparent from the following description taken in conjunction with the accompanying drawings, which constitute a part of this specification and wherein are set forth exemplary aspects of the present invention to illustrate various features thereof.
Shown in more detail in
The distal end 17 of probe 12 preferably has a length D of approximately 120 mm. As shown in
Cable 14 connected to section 26 has a length extending to LCD module 16 of about one meter. As shown in
LCD module 16 includes a processor 30 to perform calculations and control of system 10, including processing signals from the temperature sensors at locations 24A, 24B to show temperature information on a LCD display 32. A user interface 34 provides for inputting user commands such as setting desired temperatures for both food 20 and oven 22. Processor 30 preferably includes a timer, set by user inputs at user interface 34, to monitor food doneness and oven temperatures relative to desired temperatures. Power for system operation is provided by battery 35 or other suitable power source. Module 16 may further include an alarm 36, e.g., warning buzzer or LED, to warn the user of over- or under-cooking events. Additionally, module 16 may be configured to operate at up to about 140 degrees Fahrenheit such that the module can be placed in close proximity to the oven 22.
Describing the user interface 34 in more detail, a number of input buttons 52 are preferably provided to increase the functionality of the system 10, as shown in
Probe 112 and cable 114 operate much like probe 12 and cable 14 of
Probe 112 has two temperature sensors illustratively located at points 124A, 124B. These sensors are preferably thermistors as described for the aspect of the invention shown in
Cable 114 connected to wireless termination 115A has a length extending to termination 115A of about one meter. Wireless termination 115A relays signals from probe 112 as wireless signals 113 to wireless termination 115B. Wireless termination 115B may be within LCD module 116, as shown, or external to module 116, as a matter of design choice.
Wireless termination 115A may employ a “pager like” RF transmitter, known in the art and capable of operating at up to about 140 degrees Fahrenheit. Termination 115A positioned outside the oven 22 couples to cable 114 located substantially within the oven. Thus, the cable is preferably configured to withstand temperatures of up to about 570 degrees Fahrenheit. Preferably, termination 115A transmits wireless data containing information from the probe's internal temperature sensors. Optionally, wireless termination 115A includes a LCD display to show basic temperature information within oven 20 and from one or both of the internal temperature sensors.
In the preferred aspect of the invention: cables 14, 114 of
User input commands are received through user interface 34 shown at switch or input button K in
LCD display U2 has a series of lighted segments for visually displaying temperature and timer information, and communicates with processor U1 through a series of communication lines. Alarm Q1 has a speaker for providing audible alerts relating to temperature or timer values (e.g. set food or oven temperature has been reached, count up or down timer has expired). Alternatively, such alerts could appear on the LCD display U2 as flashing lighted segments, the frequency and duration of the flashing depending on what event has occurred.
Processor U1 determines when temperature measurements should be taken, which is either at set time intervals or upon user initiation through the user interface shown in
The first thermistor U4 receives a discharge of current from capacitor C9, which then travels through the resistors lrt (R4 and R11), and lrs (R2, R3, and R12) shown in
The second thermistor U4a operates in the same fashion, and simultaneously with, the first thermistor U4. The second thermistor U4a receives a discharge of current from capacitor C5, which then travels through the resistors lrt (R6 and R9), and lrs (R8, R13, and R14) shown in
The invention thus attains the features set forth above, among those apparent from the preceding description. Since certain changes may be made in the above methods and systems without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing be interpreted as illustrative and not in a limiting sense. It is also to be understood that the following claims are to cover all generic and specific features of the invention described herein, and all statements of the scope of the invention which, as a matter of language, might be said to fall there between.
This application claims priority to U.S. provisional application Ser. No. 60/304,276, filed Jul. 9, 2001, and is incorporated herein by reference.
Number | Name | Date | Kind |
---|---|---|---|
3971620 | Everett | Jul 1976 | A |
4183248 | West | Jan 1980 | A |
4348870 | Stein et al. | Sep 1982 | A |
4707588 | Takazume et al. | Nov 1987 | A |
4884626 | Filipowski | Dec 1989 | A |
4902878 | Smith et al. | Feb 1990 | A |
4973170 | Bescherer et al. | Nov 1990 | A |
5043547 | Lee | Aug 1991 | A |
5628242 | Higley | May 1997 | A |
5756970 | Barger et al. | May 1998 | A |
5900801 | Heagle et al. | May 1999 | A |
5939974 | Heagle et al. | Aug 1999 | A |
5983783 | Archard et al. | Nov 1999 | A |
6001066 | Canfield et al. | Dec 1999 | A |
6044804 | Franke et al. | Apr 2000 | A |
6068399 | Tseng | May 2000 | A |
6080972 | May | Jun 2000 | A |
6129673 | Fraden | Oct 2000 | A |
6320512 | Nicholson et al. | Nov 2001 | B1 |
6435418 | Toth et al. | Aug 2002 | B1 |
6568848 | Chapman et al. | May 2003 | B1 |
6592253 | Nyffenegger et al. | Jul 2003 | B1 |
6617581 | Pompei | Sep 2003 | B1 |
6623295 | DeLadurantaye, III | Sep 2003 | B1 |
6790178 | Mault et al. | Sep 2004 | B1 |
6817757 | Wallace | Nov 2004 | B1 |
6881055 | Bird | Apr 2005 | B1 |
Number | Date | Country |
---|---|---|
2001138834 | May 2001 | JP |
Number | Date | Country | |
---|---|---|---|
20030007544 A1 | Jan 2003 | US |
Number | Date | Country | |
---|---|---|---|
60304276 | Jul 2001 | US |