Fume cupboard provided with improved accessibility to the sash transmission system

A fume cupboard, of the type comprising a framework with two front uprights (2a, 2b), two rear uprights (3a, 3b), a rear panel (11), two side panels (6,7), an upper panel (8) and a sash (4) consisting of a frame (12) and at least one panel (13) for closing an inner chamber (10) of said fume cupboard (1), characterized in that it is provided with a transmission system (14) for transmission of vertical movements of said sash (4) located inside the front uprights (2a, 2b), or inside said front uprights (2a, 2b) and said rear uprights (3a, 3b), the front uprights and rear uprights (2a,2b;3a,3b) having an internal space (25) for housing said transmission system (14), in which said internal space (25) is provided with an opening facing the outside of the cited fume cupboard and in which said opening is closed by a door (26,26a).