Method of determining the amount of travel of a rotating component
A method of determining the amount of travel of a rotating component that includes a rotor shaft includes providing a self-contained magnetically-powered encoder. The encoder includes an encoder rotor that extends outward from a sealed housing such that a clearance gap is defined between the rotor and housing. The method also includes rotatably coupling the encoder to the rotor shaft. The method further includes measuring a first position of the encoder rotor and determining a first rotational position measurement of the rotor shaft based on the encoder rotor. The method also includes rotating the rotor shaft to a second rotational position and determining a direction of rotation and a second rotational position measurement of the rotor shaft using the encoder. The method further includes determining a total rotational distance traveled by the rotor shaft between the first rotational position and the second rotational position.
1. A method of determining the amount of travel of a rotating component including a rotor shaft, said method comprising:
providing a self-contained magnetically-powered encoder that includes at least one encoder rotor that extends outward from a sealed housing such that a clearance gap is defined between the rotor and housing;
rotatably coupling the encoder to the rotor shaft;
measuring a first position of the encoder rotor;
determining a first rotational position measurement of the rotor shaft based on the encoder rotor;
rotating the rotor shaft to a second rotational position;
determining a direction of rotation and a second rotational position measurement of the rotor shaft using the encoder; and
determining a total rotational distance traveled by the rotor shaft between the first and second rotational positions.
2. A method in accordance with claim 1 wherein providing an encoder further comprises:
providing an encoder including a plurality of magnets coupled within at least a portion of the rotor; and
coupling a plurality of switches to at least a portion of the housing, wherein the plurality of switches are oriented to receive magnetic flux generated from the plurality of magnets.
3. A method in accordance with claim 1 wherein rotatably coupling the encoder to the rotor shaft comprises:
providing a drawworks including a least one cable drum rotatably coupled to a drive shaft; and
rotatably coupling the encoder to the drawworks drive shaft.
4. A method in accordance with claim 3 wherein measuring a first position of the encoder rotor comprises coupling a drilling tool to at least one cable that is coupled to the drawworks cable drum.
5. A method in accordance with claim 1 wherein determining a first rotational position comprises transmitting the encoder first position measurement to a remote processor that is programmed with at least one conversion algorithm.
6. A method in accordance with claim 1 wherein rotating the rotor shaft to a second position comprises re-positioning a drilling tool by rotating a cable drum and the at least one encoder rotor substantially simultaneously.
7. A method in accordance with claim 1 wherein determining a direction of rotation and a second rotational position measurement of the rotor shaft comprises rotating at least one encoder magnet having a magnetic flux past at least one encoder switch, wherein the magnetic flux generated causes one of opening and closing the at least one switch.
8. A method in accordance with claim 1 wherein determining a direction of rotation and a second rotational position measurement of the rotor shaft comprises:
rotating at least one encoder magnet having a magnetic flux past a plurality of encoder switches that are spaced circumferentially across a surface of the encoder housing, wherein the magnetic flux generated causes one of opening and closing of at least one encoder switch;
generating a plurality of output signals based on the movement of each encoder switch; and
transmitting the plurality of encoder output signals to a remote processor that includes at least one of a direction of rotation algorithm, and at least one conversion algorithm.