Abstract: An electric motor used for example in a magnetic disk drive, comprises a rotor having a hub on which the magnetic disk is mounted, and an annular driving permanent magnet, and rotating together with a rotary shaft, and a stator disposed outside the rotor, having a core and coils wound on the core. A signaling permanent magnet for detecting the rotary angle or the rotational speed of the rotor may be provided on the radially inner side of the driving permanent magnet. Part of the outer periphery of the stator core may be retracted radially inward or cut away to form a concavity or an open part. A magnetic shielding plate may further be provided to cover the coils, with part or the entirety of the magnetic shielding plate being positioned closer to the rotary shaft than the outermost periphery of the rotor to prevent the escape of the rotor in the direction of the rotary shaft.

Abstract: An electromechanical transducer having a first element movable in relation to a second element, wherein the first and second elements perform a translational movement relative to one another. A transducer element mechanically coupled to the first element and second elements for converting the translational movement into an electrical signal. A transmission element converting the relative translational movement of the first and second elements into a rotating movement of the transducer element so as to produce the electrical signal.Applicant claims, under 35 U.S.C. .sctn.120, the benefit of priority of the filing date of Jun. 17, 1991, of International Patent Application PCT/NL91/00099, copy attached, filed on the aforementioned date, the entire contents of which are incorporated herein by reference. Applicant also claims, under 35 U.S.C. .sctn.119, the benefit of priority of the filing date of Jun. 19, 1990, of Netherlands Patent Application No.