摘要 |
This invention relates to a device for driving and displacing a beam in a direction parallel to guide rails, and one or more carriages rigid with the beam in a direction transverse to the displacement of the beam. The device comprises two cables 7 and 8 stretched over pulleys 5 fixed at the ends of the guide rails 3 for the beam 4, and over pulleys 6 of the beam 4. The cables 7 and 8 are wound in reverse directions on the drums 9 of the motors M 1 and M 2 which are disposed symmetrically on one and the other side of the rails, such that when the motors are rotated, they cause the displacement of the beam, or of the carriage fixed on to one of the cables, or the simultaneous displacement of the beam and carriage. |