Patent ID: 6427772
Filing Date: 2002-08-06
Classification: F25D,G07F

Abstract:
A system for electronically controlling the refrigeration and heating of a product storage compartment of a vending machine having a door, the system comprising:a vending machine having a product storage compartment and a door to the product storage compartment; a temperature sensor for sensing the temperature of the storage compartment; a door sensor for detecting whether the door of the storage compartment is opened or closed; a cooling element for refrigerating the storage compartment a heater element for heating the storage compartment; and an electronic controller connected to said temperature sensor, door sensor, cooling element, and heater element, said controller including refrigeration control means for controlling refrigeration of the storage compartment in one of a refrigeration mode with said cooling element in an ON state and a refrigeration mode with said cooling element in an OFF state, heating control means for controlling heating of the storage compartment in one of a heating mode with said heater element in an ON state and a heating mode with said heater element in an OFF state, and main control means for controlling defrosting of the storage compartment in a defrost mode with both said cooling element and said heater element in an OFF state, and for switching control between said refrigeration control means, said heating control means and said defrost mode based on signals from at least said temperature sensor and said door sensor, said main control means including a door safety timer for monitoring when the door of the storage compartment is open and a defrost timer for monitoring a time of the defrost mode.