Torque control oil pump with low parasitic loss and rapid pressure transient response

A crescent oil pump comprising:

• a housing;
• an externally toothed annular gear capable of rotation about a first axis;
• an internally toothed annular gear capable of rotation about a second axis;
• an actuating device;
• and
• a crescent body comprising an inner wall and an outer wall adapted to move from a first position to a second position by said actuating device, wherein when in the second position, to permit oil flow with the housing, the external teeth of the externally toothed annular gear are adapted to be separate from the inner wall, and the internal teeth of the internally toothed annular gear are adapted to be separate from the outer wall.

A method of controlling oil flow within a crescent oil pump comprising:

• providing a crescent oil pump comprising a housing, an externally toothed annular gear capable of rotation about a first axis, an internally toothed annular gear capable of rotation about a second axis, an actuating device, and a crescent body comprising an inner wall and an outer wall adapted to move from a first position to a second position by said actuating device, wherein when in the second position, to permit oil flow within the housing, the external teeth of the externally toothed annular gear are adapted to be separate from the inner wall, and the internal teeth of the internally toothed annular gear are adapted to be separate from the outer wall;
• moving said crescent body to said first position using said actuating device to restrict oil flow within the housing;
• and
• moving said crescent body to said second position using said actuating device to permit oil flow within the housing.

A method of controlling oil flow within a crescent oil pump comprising:

• providing a crescent oil pump comprising a housing, an externally toothed annular gear capable of rotation about a first axis, an internally toothed annular gear capable of rotation about a second axis, and a crescent body adapted to move from a first position to a second position, wherein when in the first position the crescent body is adapted to form at least one seal between a portion of the externally toothed annular gear and a portion of the internally toothed annular gear, and when in the second position the crescent body is positioned so that it does not form a seal between the portion of the externally toothed annular gear and the portion of the internally toothed annular gear;
• moving said crescent body to said first position to restrict oil flow within the housing;
• and
• moving said crescent body to said second position to permit oil flow within the housing.