Abstract: A graphics printer including a device for ensuring contact between a print medium and a guiding platform at the printing zone of the graphics printer, including a suction chamber, a suction means for creating a partial vacuum in the suction chamber located beneath the guiding platform and a plurality of orifices formed across the width of the platform communicating with the suction chamber, the print medium being guided over the platform covering a variable portion of the width of the platform as a function of the format of the print medium, the suction chamber being provided with one or more partitions separating the chamber width-wise into compartments while leaving a limited air passage section between the adjacent compartments.

Abstract: A graphics printer including a secondary guiding system comprising a fan arrangement for generating an air flux and directing the flux to a part of a print medium that hangs freely from the graphics printer, so as to maintain the hanging part away from the graphics printer or any object supported by it, preferably, in the case of a pen plotter equipped with devices for creating a partial vacuum beneath the print medium in an active zone of the writing instrument, the air flux being at least partially produced by suction devices.

Abstract: This device relates to graphics apparatus of the pen-plotter type comprising a plotter head which is moveable in a horizontal direction Y and supports a writing instrument which is vertically moveable (Z direction) on the head. Each writing instrument bears an identification surface the location of which along the Z direction depends on the instrument type. The apparatus further includes a fixed abutment. The instrument type is identified by detecting the vertical position of the instrument when the identification surface is brought into contact with the abutment. For greater accuracy, a differential measurement can be obtained between this vertical position and a reference position obtained by bringing a reference surface of the instrument into contact with a reference abutment.

Abstract: This device relates to graphics apparatus of the pen-plotter type comprising a plotter head which is moveable in a horizontal direction Y and supports a writing instrument which is vertically moveable (Z direction) on the head. Each writing instrument bears an identification surface the location of which along the Z direction depends on the instrument type. The apparatus further includes a fixed abutment. The instrument type is identified by detecting the vertical position of the instrument when the identification surface is brought into contact with the abutment. For greater accuracy, a differential measurement can be obtained between this vertical position and a reference position obtained by bringing a reference surface of the instrument into contact with a reference abutment.

Abstract: A writing tool (30) carried by a write head (10) of a drawing machine is transferred to an empty station in a storage turret by bringing the write head carrying the writing tool to a transfer position, engaging the writing tool in the station of the storage device by lowering the tool, and disengaging the writing tool from the write head by moving the write head away from the transfer position. A writing tool is transferred from a station of the storage device to the write head by engaging the writing tool on the write head by bringing the write head into the transfer position, disengaging the writing tool from its station in the storage device by raising the tool, and displacing the write head together with the writing tool away from the transfer position. Tool transfer is thus provided solely by a combination of the vertical tool movements and the displacement of the write head along a given direction as normally required for the purpose of plotting on a print medium.

Abstract: A paper sheet (10) is supported by a platen (30) having a horizontal central portion (31, 41, 51) including the write path and having front and rear portions (40, 50) for supporting the sheet in front of and behind the central portion. Each of the front and rear portions comprises a plurality of plane faces (42, 43, 44; 52, 53, 54) interconnected by horizontal edges (46, 57; 56, 57) and forming increased angles (a, b), relative to the horizontal. The selected shape of the edges and the faces is such that when the sheet (10) is resting against the second and third edges (46, 47, 56, 57) it is constrained to keep off the first and second faces (42, 43, 52, 53) and to lift above the level of the central portion (31) prior to coming into contact therewith.