High resolution non-contacting multi-turn position sensor

A multi-turn rotational position sensor, comprising:

• a rotatable shaft having a longitudinal axis;
• a movable carrier coupled to the shaft such that rotation of the shaft results in linear motion of the carrier along the longitudinal axis;
• a magnet disposed on the carrier so as to move with the carrier such that N rotations of the shaft results in a range of linear motion of the magnet along the longitudinal axis, the quantity N being greater than 1;
• a programmable integrated circuit configured to define the N rotations of the shaft as an operating range of the rotational position sensor, the programmable integrated circuit including a magnetic sensor disposed relative to the magnet and configured to measure at least two separate directional components of a magnetic field resulting from the magnet to generate an output signal representative of a longitudinal position of the magnet relative to the magnetic sensor and thus a corresponding rotational position of the shaft within the operating range the at least two directional components including a first direction parallel with a magnetization axis of the magnet and a second direction perpendicular to the magnetization axis.

A sensor for determining a rotational position of an object, comprising:

• a rotatable shaft having a longitudinal axis and configured to allow rotational coupling with the object;
• a sensed assembly coupled to the shaft such that rotation of the shaft results in linear motion of the sensed assembly along the longitudinal axis, the sensed assembly including a magnet;
• a sensor assembly disposed relative to the sensed assembly and configured to measure at least two separate directional components of a magnetic field resulting from the magnet and generate an output signal so as to allow determination of longitudinal position of the sensed assembly at a plurality of locations along the longitudinal axis the at least two directional components including a first direction parallel with a magnetization axis of the magnet and a second direction perpendicular to the magnetization axis;
• and
• a housing configured to house at least some portions of the sensed assembly, the sensor assembly, and the rotatable shaft, the housing configured to be mountable to a mounting structure, the housing dimensioned to have a curved wall, the housing further having first and second substantially straight walls extending from the ends of the curved wall so as to define a U-shape when viewed along the longitudinal axis.

A rotational position sensor, comprising:

• a housing;
• a rotatable shaft having a longitudinal axis, wherein at least a portion of the shaft is within the housing;
• a movable carrier disposed substantially within the housing and coupled to the shaft such that rotation of the shaft results in linear motion of the carrier along the longitudinal axis;
• and
• a magnet disposed on the carrier so as to move with the carrier such that a range of rotation of the shaft results in a range of linear motion of the magnet along the longitudinal axis;
• a magnetic sensor circuit disposed relative to the magnet and substantially within the housing, the magnetic sensor circuit configured to sense two or more separate components of a magnetic field resulting from the magnet and generate an output signal representative of a linear position of the magnet, and thus a rotational position of the shaft the two or more components of the magnetic field including a first direction parallel with a magnetization axis of the magnet and second direction perpendicular to the magnetization axis.