Patents Examined by Willim M. Shoop
  • Method and apparatus for fault time operating of an elevator _
    Patent number: 4506766
    Abstract: An elevator drive motor 1 is normally energized from an AC power source 8 via an AC-DC converter 4 and a DC-AC inverter 3. When the power source fails the elevator is braked and the inverter is supplied from an emergency battery 11 to access the nearest floor for passenger discharge. If a fault occurs in the inverter it is disconnected from the motor by opening a switch contact 15a, and the closing of a further contact 15b enables the converter to energize the motor in a "reverse function" mode from the battery.
    Type: Grant
    Filed: July 3, 1984
    Date of Patent: March 26, 1985
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Eiki Watanabe