Patents Assigned to Northern Power Systems, Inc.
  • Patent number: 5354175
    Abstract: A rotor hub is provided for coupling a wind turbine rotor blade and a shaft. The hub has a yoke with a body which is connected to the shaft, and extension portions which are connected to teeter bearing blocks, each of which has an aperture. The blocks are connected to a saddle which envelops the rotor blade by one or two shafts which pass through the apertures in the bearing blocks. The saddle and blade are separated by a rubber interface which provides for distribution of stress over a larger portion of the blade. Two teeter control mechanisms, which may include hydraulic pistons and springs, are connected to the rotor blade and to the yoke at extension portions. These control mechanisms provide end-of-stroke damping, braking, and stiffness based on the teeter angle and speed of the blade.
    Type: Grant
    Filed: August 30, 1993
    Date of Patent: October 11, 1994
    Assignee: Northern Power Systems, Inc.
    Inventors: Clint Coleman, William T. Kurth, Joseph Jankowski
  • Patent number: 5320491
    Abstract: A wind turbine has a rotor with at least one blade which has an aileron which is adjusted by an actuator. A hinge has two portions, one for mounting a stationary hinge arm to the blade, the other for coupling to the aileron actuator. Several types of hinges can be used, along with different actuators. The aileron is designed so that it has a constant chord with a number of identical sub-assemblies. The leading edge of the aileron has at least one curved portion so that the aileron does not vent over a certain range of angles, but vents if the position is outside the range. A cyclic actuator can be mounted to the aileron to adjust the position periodically. Generally, the aileron will be adjusted over a range related to the rotational position of the blade. A method for operating the cyclic assembly is also described.
    Type: Grant
    Filed: July 9, 1992
    Date of Patent: June 14, 1994
    Assignee: Northern Power Systems, Inc.
    Inventors: Clint Coleman, William T. Kurth
  • Patent number: 4792281
    Abstract: In a variable pitch wind turbine system, pitch angle is determined by a pneumatically pressurized hydraulic actuator connected between crank arms on the blade pitch axles. The hydraulic line extends coaxially through the rotor drive shaft via a rotary union to a gas charged accumulator on the yaw carriage. The pitch axes are positively coupled for 1:1 counter-rotation by a gear train, preferably lying on the opposite side of the rotor axis from the hydraulic actuator.
    Type: Grant
    Filed: November 3, 1986
    Date of Patent: December 20, 1988
    Assignee: Northern Power Systems, Inc.
    Inventor: Clint Coleman