Abstract: The invention concerns a single-track or multiple-track reading and/or writing head. The magnetic head comprises, for one magnetic track, two pole pieces separated by a gap (15), each being housed in a mounting made of a non-magnetic material, the pole pieces and the mounting having a common plane defining the active face of the head. The magnetic head further comprises an element (26) for closing the magnetic circuit supporting at least one coil (27).

Abstract: Disclosed is a device for setting up electrical contact among conductors distributed between a first element and a second element, the setting up of the contact between the conductors having to be made when the first element is in a determined position with respect to the second element. The devices has, inter alia a means to guide the first element towards the determined position and a stop designed to stop the first element when it has reached this determined position, this stop comprising means enabling the conductors to be gradually put into contact.

Abstract: The invention provides an armchair on which is retractably fixed at least one foot rest pivoting with respect to the frame of the armchair.According to the invention, the foot rest is locked against rotation, in its service position, by means of a rotary cam which cooperates with the adjacent upright of the frame, this cam being locked by means of a locking finger. The cam and the locking finger are mounted on one of the lateral faces of the foot rest.

Abstract: The invention provides a magnetic reading and/or writing device comprising a guide for a magnetic data carrier and a magnetic head support. The magnetic head support has a stirrup piece movable in translation with respect to a fixed piece and a magnetic head rotatably mounted on the mobile stirrup piece. The mobile stirrup piece is urged resiliently to press the magnetic head against the magnetic carrier.

Abstract: The invention relates to recording and reading heads used in the field of magnetic recording.In the case where the same magnetic head serves for these two operations, the invention proposes giving to the two rectangular facing polar surfaces defining the effective air gap, different transverse dimensions, leading to a wide recorded track due to the leakage flux and a narrow read track. This difference minimizes the influence of lateral instability in movement of the mobile magnetic support medium.

Abstract: The invention is directed to transducers for recording on (writing) and playback from (reading) a magnetizable support medium. A single transducer (head) provides both record and playback functions. Recording is carried out using a winding for inducing an external magnetic flux across a gap in the transducer and playback is carried out by sensing an internal leakage flux using a Hall effect magneto-resistive element placed outside of a gap in the head. The magneto-resistive element delivers a substantially linear electrical signal response as a function of the magnetic field applied by relative motion between the transducer gap and the support medium.

Abstract: The apparatus for the visual display of electrical signals recorded on a magnetic medium or support is in the form of a "magnifying glass" which is a plate or sheet of transparent material in which there is a dimple closed by a membrane. The volume of the dimple is filled by a mild ferrite dispersion in a liquid. Under the action of the magnetic field, the ferrite particles are displaced and give an image of the magnetic state of the media.