Oscillating fluid power generator

An apparatus for extracting power from a moving fluid stream having a variable direction of movement, said apparatus comprising:

• a mast, said mast comprising:
• a rotatable drive shaft operable for bidirectional rotation supported by a lower tower structure;
• a wing structure, substantially vertical in orientation that is operative to yaw about said mast in response to a change in the direction of the moving fluid stream and having a vertical extent, a forward portion, an upper end and a lower end, configured to present airfoil surfaces to the moving fluid stream that generate lift first in one direction that is transverse the direction of movement of the moving fluid stream and then in another direction that is opposite said one direction during mechanically-unassisted oscillation of said wing structure in the moving fluid stream, said wing structure comprising:
• a single symmetrical airfoil having a leading edge and a hinge axis or spar that is spaced away from said leading edge and to which no trim biased member is attached, and at least two stand-off arms or torque arms, each of which stand-off arm or torque arm having two ends, a first end that is fixed to said rotatable drive shaft and a second end that is pivotably attached to a said hinge axis or spar;
• and
• a power take-off mechanism that is operative to convert the bidirectional rotation of said rotatable drive shaft to unidirectional rotation in order to provide motive power to an electricity generator.

An apparatus for extracting power from a moving fluid stream, said moving stream having a direction of movement over ground, said apparatus comprising:

• a mast comprising:
• a rotatable drive shaft operable for bidirectional rotation supported by a tower structure;
• a wing structure comprising:
• at least one stand-off arm or torque arm, said stand-off arm or torque arm having two ends, a first end that is fixed to said rotatable drive shaft and a second end that is pivotably attached to a hinge axis or spar, and a single airfoil that is attached to each said hinge axis or spar, said single airfoil having no trim bias member attached thereto;
• and
• a power take-off mechanism that is operative to convert bidirectional rotation to unidirectional rotation;
• wherein said single airfoil is configured to present airfoil surfaces to the moving fluid stream that generate lift first in one direction that is transverse the direction of movement of the moving stream and then in another direction that is opposite said one direction during an oscillation of said single airfoil in the moving fluid stream, which oscillation is mechanically unassisted and is operative to cause said rotatable drive shaft to pivot back and forth;
• and
• wherein said pivoting movement is converted by said power take-off mechanism to rotational movement in order to provide motive power to an electricity generator.

An apparatus for extracting power from a moving fluid stream, said apparatus comprising:

• a mast;
• a wing structure comprising a combination having one or more horizontally oriented arms that are yawably attached to said mast and a single vertically oriented untrimmed airfoil, said vertically oriented airfoil having a leading edge and a hinge axis or spar that is disposed away from said leading edge and to which said one or more horizontally oriented arms are pivotably attached;
• and
• a power take-off mechanism that is driven either directly by a pivoting movement of said mast and said wing structure or by a pivoting movement of said wing structure with said mast remaining stationary;
• wherein said wing structure is configured to present airfoil surfaces to the moving fluid stream that generate lift first in one direction that is transverse the direction of movement of the moving fluid stream and then in another direction that is opposite said one direction during an mechanically-unassisted oscillation of said wing structure in the moving fluid stream;
• thereby maximizing the aerodynamic lift of said combination in the moving fluid stream, which in turn maximizes the conversion of the energy of the moving fluid stream into useful power.

An apparatus for extracting power from a moving fluid stream that is moving above a ground level, said apparatus comprising:

• a stationary support tower;
• a rotatable drive shaft operable for bidirectional rotation that is supported by said stationary support tower;
• a wing structure comprising at least two stand-off arms or torque arms, each of which stand-off arm or torque arm having two ends, a first end that is fixed to said drive shaft and a second end that is pivotably attached to a hinge axis or spar, and a single symmetrical untrimmed airfoil that is attached to each said hinge axis or spar, said single symmetrical untrimmed airfoil having a leading edge, symmetrically curved sides and a chord length;
• a power take-off mechanism that is operative to convert bidirectional rotation to unidirectional rotation;
• wherein said wing structure is configured to oscillate back and forth in the moving fluid stream in a self-sustaining manner that requires no mechanical assist, which oscillation is operative to cause said rotatable drive shaft to pivot back and forth;
• and
• wherein said pivoting movement of said rotatable drive shaft is converted by said power take-off mechanism to unidirectional rotational movement in order to provide motive power to an electricity generator.