Ventilator, particularly for motor vehicles

The ventilator consists of a cylindrical body (1) with a transverse wall (2) having apertures (3) separated by connecting bridges (4), and a cap (5) with a skirt (9) and a perforated base (6) with apertures (7) separated by solid sections (8) facing the end wall of the body. The cap rotates relative to the end body within limits controlled by retaining elements in the form of a groove (10) in the inner surface of the skirt and a stud (11) on the outer surface of the body, with the air flow regulated by the degree of overlap of the cap's solid sections with the bridges on the body's end wall.