Trolley Or Plow Patents (Class 246/84)
  • Patent number: 8874294
    Abstract: A trolley assist-capable electric drive truck includes a DC link with first, second and third contactors that may be opened and closed in different configurations to operate the truck in different modes. In a normal propel mode, the three contactors are open and electrical power is routed from an onboard electrical power source to electric propulsion motors. During normal retard mode, the three contactors are closed to route electrical energy generated by the electric propulsion motors through a grid resistor of the DC link. In a trolley mode, the first and second contactors are closed, but the third contactor is open, and electrical power is routed from the trolley lines to the motors for propulsion, or in a reverse direction for retarding the truck.
    Type: Grant
    Filed: June 4, 2012
    Date of Patent: October 28, 2014
    Assignee: Caterpillar Inc.
    Inventor: Lewei Qian