Position transducer
AssigneeThe United States of America as represented by the Secretary of the Army
InventorCharles D. Roach
Life of this patent
Estimating the term…
Abstract
An electrical transducer for indicating the position of an element movable n a predictable path, such as angular rotation, has no electrical parts on the movable element. A magnet mounted to the movable element traces a fixed path which lies adjacent to a stationary tubular enclosure containing liquid suspending a mass of ferromagnetic, electrically conductive material, the magnet drawing the mass of particles along within the tube on movement in its fixed path. Electrodes spaced on opposite sides of the tube wall along the length of the tube are electrically coupled by the mass of particles, whereby to indicate the position of the movable element.
Claims11
Transducer apparatus for indicating the position of an element movable in a predictable path, comprising
- magnet means mounted to the movable element, whereby the magnet traces a fixed path on movement of the element in its predictable path,
- an enclosed conduit, the conduit being mounted in fixed position apart from the movable element and extending adjacent to the fixed path of the magnet means, and
- the conduit containing a liquid having suspended therein a mass of ferromagnetic, electrically conductive material, whereby the suspended mass is drawn along within the tube adjacent to the magnetic means, and further comprising
- electrode means, extending the length of the conduit, to monitor the position of the suspended particles.
Transducer apparatus for indicating the angular position of a rotatable element having an axis of rotation, comprising magnet means, mounted to the rotatable element spaced radially outward of its axis of rotation, thereby tracing in a plane a fixed circular path on rotation of the element above its axis,
- a toroid-like enclosure, the enclosure having a tubular wall and the enclosure being mounted apart from the rotatable element in a plane parallel to the plane of the circular path traced by the magnet means with its central axis substantially along the axis of rotation of the rotatable element,
- the diameter of the toroid-like enclosure being such that its tubular wall is adjacent to the circular path traced by the magnet means,
- the enclosure containing a liquid having suspended therein particles of ferromagnetic, electrically-conductive material, and the wall having
- a bus electrode extending perimetrically around the toroid-like enclosure generally parallel to the plane of the enclosure, and
- a chain of spaced-apart position-indicating electrodes extending perimetrically around the toroid-like enclosure generally parallel to the plane of the enclosure and spaced transversely from the bus electrode.
Dependencies are inferred from the claim text.