Ing C. Olivetti C., S.p.a.

Piero Gontero

Riccardo Forlani

Bruno Cestari

The photocopier uses a development process employing a magnetic brush formed on a rotating sleeve (102) of non-magnetic material in which a system of permanent magnets (108) rotates. The outer surface of the sleeve is subjected to a sandblasting process after grinding in order to create a very uniform finely roughened surface in order to make the thickness of the toner layer forming the magnetic brush constant. The photocopier also employs a toner fixing system operating cold and under pressure by means of a pair of rollers (56, 58) of different diameter rotating at the same angular speed in order to create slippage of the upper roller relative to the lower roller for the purpose of obtaining perfectly flat copies. The copier also contains a single circuit board (80) for the low voltage and high voltage supply.

Electrophotographic copier

An electrophotographic copying machine in which the drum is rotatable about a given axis and is at least partly formed by a plurality of sectors each having a surface constituting part of the cylindrical periphery of the drum and each being mounted within the drum as to be slidable in a direction perpendicular to the said axis between a first position in which it defines the respective part of the cylindrical periphery of the drum, and a second position into which it is shifted radially with respect to the remainder of the cylindrical periphery; each of the sectors has a portion of a photoconductive band wound around its surface and extending from a feed reel to a take-up reel; these reels are mounted inside the respective sector and reversible locking means are provided for maintaining the sectors in their first position during the rotation of the drum about the said axis.

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Bollengo (Turin), Italy

Piero Gontero