Abstract: The invention relates to a printing apparatus of the type which transfers an image without impact. This apparatus includes a flexible recording tape (20), a printing block (28) which is displaced along the tape so as to record latent images onto it and deposit a powdered developer onto these images, the developer thus forming these images in powder. A press cylinder (53) enables the tape (20) to be pressed onto a print carrier (11), which assures the transfer of the powder images onto this carrier. The invention is applicable to the printing of data in a data processing system.

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 magnetographic printing process, as well as to a achine which enables images in color to be produced on a print carrier. The machine which carries out this process comprises magnetic heads (13-1, . . . , 13-n) excited by pulses emitted by a generator (26) by means of a current calibrating means (27) to produce on the drum (10) magnetized points having different magnetizations, pigment applicator means (40, 42, 44), retouching means (41, 43), and a transfer station (45) where the pigments deposited onto the drum (10) are transferred to a paper strip (21).The electric current calibrating means is connected between the pulse generator and each of the heads so as to allow each of the current pulses emitted by the generator to be adjusted selectively to one of the p predetermined amplitude values and thus to produce on the recording surface a latent magnetic image whose magnetized points exhibit the same magnetic polarity but have different intensities of magnetization valued as J.sub.

Abstract: The invention relates to a printing process, as well as to a machine which enables images in color to be produced on a print carrier.The machine which implements said process comprises magnetic heads (13-l, . . . 13-n) energized by impulses emitted by a source (26) by means of a frequency-generating means (27) in order to produce on the drum (10) magnetized points having different sizes, pigment-applying means (40, 42, 44) retouching means, and a transfer station (45) where the pigments deposited onto the drum (1) are transferred to a strip of paper (21).

Abstract: The invention relates to a printing process and machine which enables the production of two-color images on a print carrier. The machine which carries out this process consists of two applicators (40,42) placed one after the other to deposit two layers of differently colored pigments onto the magnetic drum (10). The surface of the drum has produced thereon a latent magnetic image whose magnetic points have the same intensity of magnetization, but opposite polarities, the magnetic points intended to produce powder-image parts in one of said colors being opposite to that of the points intended to produce the other parts of said image. A transfer station (44,45) is provided with a magnetic field generator (21) located upstream to the point (45) where the pigments are transferred to the print carrier (20). The magnetic-field generator (21) applies a constant magnetic field to the recording surface in a direction perpendicular to the surface.