REPLACING DEVICE FOR PROJECTION UNIT

PURPOSE:To simply replace a projection unit with another unit by providing a long side member on which a heavy member is suspended from a ceiling face at the end of a space not giving effect on an image light formed between the projection unit and a screen. CONSTITUTION:A projection unit 1 whose service life is estimated to be terminated is drawn on a moving base 7 from a housing 3 and mounted nearly in the middle, the moving base 7 is moved to a side face of the housing 3, a ceiling plate 26 is open, an arm 9 is pivoted around a rotating shaft 20, a rope 22 is stretched to a hook 21 of pulley sets 15 provided to a tip of the arm 9 and connected to an I bolt 23 provided to the projection unit 1, the pulley 15 is moved to descend the projection unit 1 at the outside of a multi-vision 101. The lope 22 is stretched to the I bolt 23 provided to a new projection unit 1 prepared in advance, and set to the hook 21 of the pulley 15 and the new projection unit 1 is hung down and mounted nearly in the middle of the moving base 7 and moved and installed after the projection unit 1 whose service life is estimated to be terminated. The projection unit is simply replaced without trouble and it is not required to reserve a new maintenance space.