Proctor-silex, Inc.

Harry Hill Associates

Other

Eugene J Sturdevant

John F Daniels

In an electrical oven at least one corona generation electrode is provided to enhance heat and mass transfer. Food being cooked in the oven provides a second electrode which is normally supported on insulating support structure and provided with high potential through the use of a probe inserted into the food. A high voltage potential supply and constant current high voltage control are connected between the two electrodes. The corona generating electrode has a plurality of corona discharge generators with pointed or small diameter free ends fixed at their opposite ends to a common conductive base. The corona discharge generators are flexible and have current conducting capability and are connected to the conductive base so as to yield under pressure but to return to operative position upon imposition of corona producing potential. The corona discharge generators are preferably metallic foil, insulator sheet covered with foil or conductive fibers. It is desirable to provide internal resistance within the individual corona discharge generators by making them of somewhat resistive material, tipping them with resistive material or otherwise providing series resistance which will make it possible then for these flexible electrodes to be self-adjusting. Individual self-adjusting corona discharge generators withdraw from the other electrode to suppress an arc or various ones of them selectively withdraw to provide a profile conforming to the profile of the food constituting the other electrode even as it changes in the course of cooking.

Electrodes for enhanced heat and mass transfer apparatus

A cooking oven has an enhanced heating structure for decreasing the cooking time relative to conventional ovens. The enhanced heating structure located on the bottom of the oven has a plurality of spaced apart upward projecting needle electrodes and a heater element located adjacent the needle electrodes. A frame and a flat plate form an enclosure of selected volume for enclosing the needle electrodes and the heater element. The flat plate supports the food for cooking and provides safety and ease of cleaning for the user. An electrical circuit generates a high voltage between the flat plate and the needle electrodes for increasing the rate of heat transfer from the heater element to the flat plate. The temperature of the selected volume enclosed is separately monitored and independently controlled.

Heating structure for an oven

An electrode shield device for use in conjunction with a needle electrode preferably embodied in an oven. The shield device includes a perforated plate and mechanical means supporting the plate for causing relative movement between the plate and the needle electrode. In operation, the mechanical means locating the plate in a spaced relationship to cover the needle electrode for preventing physical contact with the needles when the electrode is electrically inactive and the mechanical means locating the plate in an engaging relationship to expose the needles for permitting the needles to establish current contact with, for example, high potential food.

Electrode shield device

A mechanical electrode is disclosed for use in an electrical circuit in a cooking device, such as, an oven. The mechanical electrode includes a plurality of electrically conductive needle elements supported on a flat base plate. Each needle has a sharply pointed tip for establishing current contact through an electrical field with a food supplied with a voltage normally sufficient to generate corona current from the tip to an aligned surface of the food for enhancing heat and mass transfer. A current-limiting resistive material electrically connects each one of the needle elements to the base plate which, in turn, is electrically coupled to a voltage supply for regulating the voltage supplied to the food to complete the electrical circuit. The current-limiting resistive material forming a discrete path of electrical resistance along each needle so that any excessively high voltage concentration about any needle is restricted through the resistive material and confined to individual needles for suppressing arc formation. In this manner high voltage in the electrical field is avoided, the voltage supply is protected from receiving any sudden high voltage surge and adjacent needle elements are allowed to continue in corona current generating operation.

Mechanical electrode

An apparatus in a cooking device, e.g., an oven, is disclosed for enhancing heat and mass transfer during the food cooking process. The apparatus applying differently controlled corona currents to food surfaces in order to reduce cooking times relative to cooking times of conventional ovens. Two low potential electrodes, one fixed and the other movable, are provided in the oven and food, located intermediate the electrodes, is maintained at a high potential. A pair of electrically conductive fields for supporting corona currents at predetermined different corona current densities are defined between each electrode and its nearest food surface. Electrical circuitry is provided for maintaining a constant corona current flow in each one of the two electrical fields and each electrical field is controlled to support corona current flow at a different optimum density found to maximize heat and mass transfer. In operation, the corona current density in one electrical field is electrically monitored to adjust the high potential supplied to the food in order to maintain optimum corona current density in that electrical field. The corona current density in the other electrical field is electrically monitored to electromechanically adjust the movable electrode towards and away from the food, according to the high potential of the food, in order to maintain optimum corona current density in the other electrical field.

Growing community of inventors

Wilmington, DE, United States of America

Eugene J Sturdevant