Temperature self-regulating food delivery system

• US 20020063124A1
• Filed: 01/15/2002
• Published: 05/30/2002
• Est. Priority Date: 05/19/1998
• Status: Active Grant

• Current Assignee: TSI SUB LLC
• Original Assignee: Amil Ablah, Clothier Brian, David May, Robert Wolters, William Heine
• Inventors: May, David, Ablah, Amil, Clothier, Brian, Wolters, Robert, Heine, William
• Granted Patent: US 6,504,135 B2
• Time in Patent Office: Days
• US Class Current: 219/622
• CPC Class Codes: H05B 2213/06 Cook-top or cookware capable of communicating with each other
• CPC Class Codes: H05B 6/06 Control, e.g. of temperature, of power

Abstract

Temperature self-regulating food delivery systems are provided having a magnetic induction heater (32, 126) and an associated food container (76, 124) equipped with an essentially permanent ferromagnetic heating element (82, 100, 128). The heater (32, 126) and heating elements (82,100, 128) are designed so as to heat the element (82, 100, 128) to a user-selected regulation temperature when the elements (82, 100, 128) are coupled with the heater'"'"'s magnetic field, and to maintain the temperature in the vicinity of the regulation temperature indefinitely temperature regulation is a heating achieved by periodically determining at least two parameters of the heaters resonant circuits related to the amplitude of the resonant current passing therethrough during heating and responsively altering the field strength of the magnetic field. Preferably, the value of the resonant circuit amplitude and the rate of change of the amplitude are determine.

Claims

1. A heating assembly comprising:

a magnetic induction heater including a heater circuit having a magnetic field generator, a detector operable to detect a heater circuit parameter related to the impedance presented to the heater by an induction heatable device, and control circuitry capable of altering the magnitude of said magnetic field generated by said generator in response to said detection of said parameter; and

an induction heatable device including a continuous coil formed of electrically conductive material with a pair of terminal coil ends, and a conductive assembly operably connected between said terminal coil ends to complete a circuit, said conductive assembly comprising a selectively operable switch component switchable between a circuit-make configuration and a circuit-break configuration,

said coil experiencing a magnetically induced flow of current therethrough when said generator is operating, said switch is in the circuit-make configuration thereof, and said device is placed adjacent said heater to present a circuit-make impedance to the heater,

said coil experiencing a circuit-break impedance different than said circuit-make impedance when said switch is in said circuit-break configuration,

said device and heater cooperable so that, when said switch moves between the circuit-make and circuit-break configurations thereof, said detector detects a change in said parameter, and said control circuit operates to alter the magnitude of said magnetic field.

2. The heating assembly of claim 1, said parameter being the magnitude of current passing through said heater circuit, or the rate of change of said magnitude.

3. The heating assembly of claim 1, said conductive assembly including an electrically conductive wire element connected to each of said terminal coil ends, with said switch component connected between the ends of said wire elements remote from said terminal coil ends.

4. The heating assembly of claim 1, said switch component comprising an electronic switch.

5. The heating assembly of claim 1, said control circuitry operable to terminate the operation of said magnetic field generator.

6. The assembly of claim 5, said electronic switch being programmable.

7. The assembly of claim 1, said control circuitry operable to alternately terminate or maintain the operation of said magnetic field generator.

8. The assembly of claim 1, said coil formed at least in part of a ferromagnetic material.