A position and speed detecting device is provided. This device includes a detection-signal generator comprising a rotor magnet assembly having a plurality of magnetic poles and a coil pattern for signal detection which moves relatively facing magnetized bodies of the rotor magnet assembly, a speed-signal detector for taking out a signal for frequency detection from said coil pattern for frequency-signal detection to produce a signal for speed detection; and a position-signal detector for producing a signal for position detection from said coil pattern for position-signal detection. An interface of at least one pair of S and N magnetic poles slanted at an angle different from that of interfaces of other magnetic poles and a part of coil pattern in the coil pattern for signal detection is slanted at an angle substantially the same as that of the magnetic poles for position-signal detection and other part of coil pattern is formed at an angle substantially the same as that of the magnetic poles for frequency-signal detection to make it a coil pattern for frequency-signal detection.

In a rotation sensor for generating a signal indicative of a reference rotational angle or position of the rotary member, the arrangement of elements, such as magnetized areas or sector, as well as the arrangement of associated signal generating circuits, such as convex and concave coil portions arranged circumferentially, is improved so that both speed signal and reference rotational angle signal can be obtained from a single output signal from the series circuit of the signal generating circuits. In one embodiment, magnetized areas as well as convex portions of an associated wave-like coil pattern are arranged according to geometrical progression so that the magnetized portions and the convex portions agree with each other only once per rotation of the rotary member over a predetermined angle to develop a higher voltage, while low voltage is generated on nonagreement.

An inductive-type rotary encoder includes a stator having at least one conductive pattern on one side thereof, and a rotor having another conductive pattern on one side thereof which faces the at least one conductive pattern of the stator. The conductive patterns are inductively coupled to one another so as to generate an output signal indicative of the angular position of the rotor relative to the stator. In order to reduce the overall size and number of parts required, the circuitry for energizing the stator conductive pattern(s) and for generating the output signal can be provided on a printed circuit board, the opposite side of which contains the at least one stator conductive pattern. In order to reduce noise as well as to reduce the first harmonic error, lead lines for attaching the stator and rotor conductive patterns to the controlling circuitry and a return line which extends along substantially the entire length of the rotor or stator conductive patterns and attaches to one of the lead lines are provided and specially located relative to undulations of the conductive patterns. Additionally, the length of spokes which define undulations of the respective rotor and stator conductive patterns can be controlled to improve the performance of the rotary encoder. A rotary encoder including inductively coupled rotor and stator conductive patterns for generating a relative angular position (or rotary speed) of the rotor relative to the staator, as well as stator and rotor index pulse patterns inductively coupled for generating an index pulse once per revolution of the rotor relative to the stator is also provided.

An integral variable reluctance sensor and bearing grease seal assembly (sensor assembly) has at least one magnet and an annular wire coil secured at the interior of a housing which seals an annular space between a dynamic inner race and a static outer race. The sensor assembly is characterized by a relatively large flux change and resulting large peak to peak periodic output due to exploitation of the outer race and housing as high permeance flux paths in the sensor magnetic circuit and an additive arrangement of plural magnets. Sensor output signal strength is variable in step with the number of magnets and output variations due to air gap variations are minimized by symmetrical distribution of the same. The sensor assembly is further characterized by a single dynamic seal and no moving parts.

A rotation sensor inlcudes circuitry for sensing both small units of rotation of a rotating body relative to a stationary body and a predetermined angular orientation of the former to the latter, and is designed to prevent electromagnetic interference between the rotation sensor circuitry (FG) and angular position sensor circuitry (PG). The FG circuit defines a full annular ring about the axis of the rotating body whereas the PG circuit covers a relatively narrow annular sector. The FG and PG circuits lie at different radial positions and do not overlap radially. Corresponding PG and FG magnetic rings fixed to the stationary body opposite the PG and FG circuits consist of annular sectors magnetized to alternating polarities. The symmetrical spacing of the FG magnetic sectors matches the angular spacing of FG circuit elements oriented perpendicular to the magnetic flux generated by adjoining magnetic sectors. The PG magnetic sectors match both the spacing and the total angular extent of the PG circuit. As the PG and FG circuits rotate, the corresponding magnetic sectors induce electric fields, resulting in the desired sensor signals. The PG and FG circuits are connected in parallel to a common electrical terminal. Connections from opposite ends of the FG circuit to the common terminal and to the FG output terminal may be curved so as to maximize their length in the magnetic flux region while minimizing their obliquity to the magnetic flux lines.