Electronically Controlled Warmer Drawer

Abstract

An electronically controlled warmer drawer for food or non-food items having a housing including a heating element based on several heat-producing technologies, temperature and/or humidity sensor(s), and a fan to effectively warm items placed therein. The system is controlled by way of the user interface that interacts with an electronic control system to operate the heating element and fan. The user interface provides user programmable controls and automatic overrides, can be placed in a variety of locations, and can be concealed by a variety of elements. The interface can also utilize a variety of touch sensitive technologies. As well, the device may have a receptacle for adding fragrance or flavor to the objects within.

We claim: 
     
         1 . A warmer drawer comprising:
 a housing having a cavity;   an extendable portion slidably connected to the housing, wherein the extendable portion is sized to fit within the cavity;   a door connected to the extendable portion;   a heating element located in the cavity;   a fan for moving heated air within the cavity;   electronic controls for operating the fan and the heating element; and   a sensor in communication with the electronic controls for controlling a humidity in the cavity and a current supplied to the heating element.   
     
     
         2 . The warmer drawer of  claim 1 , further comprising a venting system that is controlled by the humidity sensor and the electronic controls to open and close one or more vents in the cavity and control an air flow through the one or more vents. 
     
     
         3 . The warmer drawer of  claim 1 , further comprising a panel configured to conceal the electronic controls, wherein the panel is one or more selected from a group comprising a sliding panel, a sliding spring-biased panel, a sliding panel display, a panel on a rotating element, an L-shaped plate, a matching panel, and a portion of a rotating element having at least one electronic control thereon. 
     
     
         4 . The warmer drawer according to  claim 1 , wherein the electronic controls comprise programmable on/off settings having automatic shutoff with an infinite setting of the automatic shutoff to disable the automatic shutoff. 
     
     
         5 . The warmer drawer of  claim 1 , further comprising a receptacle for receiving aromatic materials wherein the aromatic materials are one or more selected from a group consisting of a fragrance source, a flavoring additive, wood chips, and a liquid smoke. 
     
     
         6 . The warmer drawer of  claim 1 , wherein the heating element is one or more selected from a group consisting of a convection heater, a calrod, a heat plate, a glass film, a thermal ceramic heater, a flexible heater, a light, an infrared device, an inductive device, an electromagnetic device, a radio frequency device, a heat pump, a warming liquid device, a heat exchanger, an axial fan heater, a sonic heater, a gas fuel product, a solid fuel product, a radiant heating device, and a microwave device. 
     
     
         7 . The warmer drawer of  claim 1 , wherein the electronic controls comprise an electronic display touch control panel having one or more input elements configured to respond to a user input and at least one operating technology of the input elements is one or more selected from a group consisting of a piezo electric, a capacitive, a resistive, and an infrared. 
     
     
         8 . The warmer drawer of  claim 1 , further comprising at least one of an upper chamber and a lower chamber wherein the fan is located in one or both of the upper chamber and lower chamber. 
     
     
         9 . The warmer drawer of  claim 1 , wherein the electronic controls are located on at least one of the extendable portion and the door. 
     
     
         10 . The warmer drawer of  claim 9 , wherein the electronic controls are configured to be concealed by an overlying panel by moving the extendable portion to a closed position. 
     
     
         11 . A method of manufacturing a warmer drawer, comprising steps of:
 defining an enclosure with a chamber and having an opening;   configuring a movable portion to be moved with respect to the chamber;   providing a heating element to heat the chamber;   configuring a user interface to receive input from a user for controlling operation of the warmer drawer;   providing a sensor to sense a signal representative of a temperature of the chamber;   configuring an electronic control system for interfacing with the heating element, the user interface, and the sensor to control a supply of electrical power in a continuous and regulated manner to the heating element during operation of the warmer drawer; and   controlling the humidity in the chamber.   
     
     
         12 . The method of  claim 11 , further comprising the step of providing a second sensor selected from the group consisting of a humidity sensor, a temperature sensing, a thermostat, a thermal protector, a thermal cutoff, a thermal switch, a thermocouple, a PCB thermostat, a time delay relay, a bulb and capillary device, a cold control, a bimetallic device, a pressure switch, a resistance temperature detector, a snap action switch, and a thermistor device, configured to interface with the electronic control system. 
     
     
         13 . The method of  claim 11 , further comprising the step of connecting the user interface having an electronic display touch control panel configured to provide information to a user. 
     
     
         14 . The method of  claim 13 , wherein the step of connecting the user interface having the electronic display touch control panel utilizes a display panel having technology selected from the group consisting of light-emitting diodes, a liquid crystal display, a plasma, a dot matrix, and a vacuum fluorescent display. 
     
     
         15 . The method of  claim 1 , further comprising the step of providing an element configured to hide the user interface. 
     
     
         16 . The warmer drawer of  claim 1 , further comprising a partition within the cavity that divides the cavity into an upper chamber and a lower chamber. 
     
     
         17 . The warmer drawer of  claim 16 , further comprising a back plate that includes a plurality of apertures, and wherein the back plate is positioned within the cavity so as to form a space between a back wall of the warmer drawer and the back plate, and wherein the fan forces air into the space, through the apertures, and into the lower chamber. 
     
     
         18 . The warmer drawer of  claim 1 , wherein a humidity inside the cavity is controlled by the humidity sensor and the electronic controls by regulating the fan.