Abstract: The invention relates to a device for forming latent magnetic images on the recording element of a magnetographic printer.A plurality of magnetic heads (such as Y1, X1, Y2, and so forth), of different sizes are provided which can be displaced along the surface of the recording element (11) and which are excited selectively in such a manner as to form magnetized points of different sizes on this surface, which are centered along the lines (D1, D2, D3 and so forth), this excitation being effected such that the magnetized points thus formed on the surface do not overlap.

Abstract: The invention relates to a device for intermittently applying particles of a powdered developer to the recording surface of a magnetographic printer. This device includes a reservoir (17) containing developer particles, a transport element (23) for placing these particles in the vicinity of the surface of a magnetic drum (11), a deflector (24) disposed between this transport element and the drum to apply the particles to the drum surface, and a squeegee (45) disposed between the deflector and the transfer station (H), and actuated by an electromagnet (EA) for selectively pulling away the particles that have been deposited on the drum surface. The invention is applicable to magnetographic printers.

Abstract: The invention relates to a powdered substance for lubricating the recording carrier of a magnetic printer. This solid substance is in the form of a powder comprising groups (G) of particles, each of these groups being formed by one particle (30) of lubricating insulating material surrounded on its periphery by particles (31) of conductive carbon, the number of the latter particles being sufficient to cover the entirety of the external surface of this particle of lubricating insulating material. The invention is applicable to magnetography.

Abstract: A method for manufacturing a magnetic transducer including a plurality of heads. This method comprises placing p magnetic cores (such as 17-4) on a support plate (20), each core being provided with a winding (such as E4) extending over the entire length of the core, coating these cores within an insulating film (25), removing the turns located at the ends of each core, and connecting the turns (29, 30) located at the ends of the remaining turns to contact zones (37c, P-1, P-2, etc.). The method applies to the manufacture of transducers with which magnetic printing machines are equipped.

Abstract: The invention relates to an apparatus for developing latent magnetic images used for example in magnetic printing machines. This apparatus includes a retouching device (20) comprising, first, a transport roller (27) which is displaced in the direction opposite that of the magnetic recording surface (13) in proximity with which it is placed and, second, a magnet (31) disposed in the interior of the roller (27) in such a manner that facing this surface it has a pole (32) the polarity of which is opposite that of the magnetized zones (14) of this surface, the magnetic axis (N'S') of this magnet being inclined in the opposite direction from that of the displacement of the surface (13).

Abstract: The invention relates to a device that permits removal of excess developer particles on the surface of a recording element and comprises a suction conduit (22) having at one end a port (23) in the form of a slot and at its other end a cylindrical chamber (25) which communicates with said conduit. The generators of the chamber run parallel to the port (23). The chamber includes a suction port (32) which is connected to a suction source, and an air inlet port (31) which discharges into the free atmosphere (31).

Abstract: The invention relates to magnetic printers and, more particularly, to an apparatus for applying solid developer particles to the recording drum of a non-impact printer. This apparatus comprises, on the one hand, a conveyor roller (22) which brings the developer particles from a particle storage or supply tank (15) to the vicinity of the recording drum (10) and, on the other hand, a baffle plate or deflector (23) positioned between the roller (22) and the drum (10). The roller (22) is coated with magnetized strips having on their outer surfaces magnetic helicoidal lines such that on two adjacent strips the pitch of the magnetic lines of one strip is opposed to that of the other strip.

Abstract: Apparatus for applying solid particles to the image carrier of a non-impact printer comprises a tank (6) containing a supply of the particles and includes a cylindrical conveying device (21) mounted for rotation in the tank on a first axis A3. A cylindrical conveying member (14) is also mounted for rotation in said tank on a second axis A2, while a first deflector (15) is interposed between the conveying member (14) and the carrier (2), and a second deflector (22) is interposed between the conveying device (21) and the conveying member (14) so as to cause transfer of particles in the tank to the conveying device (21), from there to the member (14) and thence to the carrier (2). Stirring devices (27) for stirring the particles in the tank may also be provided to establish a suitable reserve of particles and supply the particles to the conveying member with evenness.