Patent ID: 6342775
Filing Date: 2002-01-29
Classification: B63H,H02J

Abstract:
A battery switching circuit, comprising:a first battery having a positive terminal and a negative terminal; a second battery having a positive terminal and a negative terminal; a third battery having a positive terminal and a negative terminal; a source of charging power; a manually controlled electrically operated device having an active state and an inactive state; a first switch, connected to said first battery, having a first state in which said positive terminal of said first battery is connected to said source of charging power and a second state in which said positive terminal of said first battery is disconnected from said source of charging power; a second switch, connected to said first and second batteries, having a first state in which said negative terminal of said first battery is connected to said negative terminal of said second battery and a second state in which said negative terminal of said first battery is connected to said positive terminal of said second battery; a third switch, connected to said second battery, having a first state in which said positive terminal of said second battery is connected to said source of charging power and a second state in which said positive terminal of said second battery is disconnected from said source of charging power; a fourth switch, connected to said second battery, having a first state in which said negative terminal of said second battery is connected to said negative terminal of said third battery and a second state in which said negative terminal of said second battery is connected to said positive terminal of said third battery; and a switch controller for causing said first, second, third, and fourth switches to be in a first condition when said manually controlled electrically operated device is in said inactive state and for causing said first, second, third, and fourth switches to be in a second condition when said manually controlled electrically operated device is in said active state.