Patent ID: 6425461
Filing Date: 2002-07-30
Classification: B66B

Abstract:
A double backup power device for an elevator comprising:motor means; a control within a car of said elevator, said control comprising a startup button, an up button, and a down button; and a backup power assembly comprising a primary battery, a secondary battery, an electrolytic container for storing an electrolyte being disposed above and in fluid communication with said secondary battery, a check valve on said electrolytic container for controlling a flow of said electrolyte, and a switch in a series connection with said primary and said secondary batteries which are parallel connected to said motor means; and wherein when said car is disabled, one of persons trapped in said car is permitted to press said startup button to activate said backup power assembly; said switch is closed for electrically interconnecting said primary and said secondary batteries and for activating said motor means; said check valve is open for permitting said electrolyte to continuously drop from said electrolytic container to said secondary battery for charging; and said up or said down button is operative to carry said car to one of a predetermined locations for evacuating persons.