A molded article 1 is configured such that an insert 2 is made of a steel plate and includes a cylindrical part 2A and an annular part 2B, a plastic 4 is annular in shape so as to be joined to the annular part 2B, inner diameter D1 of the plastic 4 is larger than inner diameter D2 of the annular part 2B so that no burrs at a gate mark E protrude to the inner diameter side of the molded article 1, the injection molding is conducted with a disc gate arranged on an inner peripheral surface F of the plastic 4 at a position separated from a surface of the annular part 2B, and the gate mark E resides on the inner peripheral surface F of the plastic 4 at a position separated from the surface of the annular part 2B.

To provide a magnetic encoder in which a base material has a ring-shaped body portion into which a rotation axis is inserted when a magnetic drum is mounted on a rotation axis, and an engagement convex portion provided so as to project over a whole circumference of an outer periphery of the body portion. The body portion has a centering track provided in a part of the outer periphery of the body portion over the whole circumference as a reference of circular runout tolerance on an outer periphery of a magnet. The engagement convex portion has a constricted portion projecting from the outer periphery of the body portion, and a cylindrical portion extending in an axial direction of the body portion from a tip end of the constricted portion. The magnet surrounds the engagement convex portion so as to wrap around to a gap between the cylindrical portion and the body portion, and exposes the centering track without covering the centering track.

Embodiments relate to a position sensor comprising a magnetic target. The magnetic target includes a magnetic multipole configured to generate a magnetic field. The magnetic field has three mutually-perpendicular components at a first region. Sensor elements can be configured to measure these field components at the first region. In embodiments, comparing the amplitudes of the components can be used to determine a global position, and the instantaneous values of these components can be used to determine a local position.

A scale includes a glass substrate having a frosted glass-like upper surface, a plurality of conductor patterns arranged at predetermined intervals on the upper surface of the glass substrate, and a formation provided on a lower surface of the glass substrate.

A magnetization apparatus for a magnet of a magnetic encoder. The magnetization apparatus is configured to alternately form a positive and a negative magnetization areas by moving a magnetic member along a route penetrating a gap of a magnetization yoke while alternately generating positive and negative magnetic fields in the gap of the magnetization yoke. The magnetization apparatus includes a power supply part configured to supply electric power to a coil wound around the magnetization yoke; an area setting part configured to receive magnetization pattern information specifying arrangement of the magnetization areas relative to the magnetic member; a positional information generation part configured to output positional information of the magnetic member moving along the route; and a control part configured to control the power supply part in such a manner that each portion of the magnetic member corresponding to the magnetization area specified in the magnetization pattern information receives corresponding positive or negative magnetic field based on the positional information outputted from the positional information generation part.

An axial-type magnetic encoder includes an annular fixing member that is fabricated by press molding, and an annular plastic magnet that is attached by injection molding to a sensor-opposed surface of the annular fixing member. When the annular fixing member includes a cylindrical part and an inward flange part extended radially inward from an end edge of the cylindrical part, the magnetic encoder has a high-form accuracy surface on the sensor-opposed surface more radially outward than a range of a diameter (d2.Math.r) determined by an inner diameter d of the cylindrical part and a radius r of a corner between the cylindrical part and the inward flange part. An outer diameter of the annular plastic magnet is positioned on the high-form accuracy surface.

An electromechanical actuator includes a ground arm, an output arm rotatable about an axis of rotation relative to the ground arm and a position sensing arrangement to determine an angular position of the output arm relative to the ground arm. The position sensing arrangement includes a position sensor fixed at the ground arm. The position sensor is configured to sense magnetic reluctance. A sensed portion is located at the output arm proximate to the position sensor. The sensed portion includes a geometric variation in an output arm surface configured to vary a magnetic reluctance sensed at the position sensor as a function of angular position of the output arm relative to the ground arm.

Apparatus and methods for generating a uniform magnetic field are provided herein. In certain configurations, a magnetic structure includes one or more pairs of magnets positioned within a housing. The magnets of each pair are arranged in parallel and include poles that are reversed in polarity relative to one another. For example, in certain implementations, a first pair of magnets includes a first magnet and a second magnet arranged side by side, with a north pole of the first magnet adjacent a south pole of the second magnet and with a south pole of the first magnet adjacent a north pole of the second magnet. The housing is implemented using a magnetic redirecting material, which can confine magnetic flux and reduce stray magnetic fields. The magnetic structure can be used to generate a magnetic field that is substantially uniform in a region of interest.

In a magnetization device, while an annular magnetic body including plural rows of annular un-magnetized magnetic encoder tracks which are arranged adjacent to each other and integrated therewith is rotated, magnetization is performed, thereby providing a magnetic encoder. The magnetization device includes: a magnetizing yoke including a pair of opposed end portions opposed to each other across a magnetic gap; an exciting coil wound on the magnetizing yoke; a magnetization power source supplying a magnetizing current to the exciting coil to pass magnetic flux between the opposed end portions; and a magnetic shield which is provided to the magnetizing yoke and shields flow of the magnetic flux to the rows of magnetic encoder tracks other than a magnetization target.

A magnetization apparatus for a magnet of a magnetic encoder. The magnetization apparatus is configured to alternately form a positive and a negative magnetization areas by moving a magnetic member along a route penetrating a gap of a magnetization yoke while alternately generating positive and negative magnetic fields in the gap of the magnetization yoke. The magnetization apparatus includes a power supply part configured to supply electric power to a coil wound around the magnetization yoke; an area setting part configured to receive magnetization pattern information specifying arrangement of the magnetization areas relative to the magnetic member; a positional information generation part configured to output positional information of the magnetic member moving along the route; and a control part configured to control the power supply part in such a manner that each portion of the magnetic member corresponding to the magnetization area specified in the magnetization pattern information receives corresponding positive or negative magnetic field based on the positional information outputted from the positional information generation part.