Ventilation unit with box-shaped housing - has grooves in inside housing surface near lower edges of openings

摘要

The ventilation unit has a box-shaped outer housing formed from a continuously extruded injection moulding and of rectangular cross-section, so as to fit into a window-frame, with openings towards outside and inside. Grooves (11,12) are formed in the inside surface (6) of the outer housing (1) between the lower edges (9,10) of the outside and inside openings (7,8,5), and preferably near the latter. Between the groove (12) near the inside opening (5) and the lower edge of the latter there can be a strip (13), to which there is detachably secured a grille or a hinging shutter.