| 摘要 |
<p>A substantially closed casing having two pairs of parallel side walls (2, 2 min ) and (1, 3 min ) respectively a rear wall (4) and a front cover. In the casing a fan (16) is mounted with its discharge side in communication with an outlet (30) in a wall of the casing and with its suction side in communication with a intake aperture in a wall of the casing through a passageway, in which passageway an apparatus (15) for filtering the intake air is provided for removing solid particles from said air. The casing is divided into a first and a second compartment by a pair of partitions (9, 9 min ) extending in spaced apart relation in parallel to each other and to a pair of side walls (2, 2 min ) of the casing and extending between the other pairs of side walls (1, 3) of the casing, and defining a channel (10) which through an aperture (11) in one (9 min ) of the partitions near a side wall of the other pair communicates with a space (12) adjacent to said partition (9 min ) and closed with respect to the remaining part of the second compartment of the casing. In said space (12) the intake aperture opens. Through an aperture (13) provided in the other partition (9) and adjacent to the other opposite side wall of the casing said channel (10) communicates with the first compartment of the casing in which an apparatus (14) for controlling the temperature, the apparatus (15) for filtering the intake air and the fan (16) are located. The discharge side of said fan (16) is connected to a discharge duct (20) extending through the channel (10) and the closed space (12) and opening into a second channel (22) parallel to the first channel (10). At the one side the channel (22) is defined by the side of the sealed space (12) and a side of at least one filter element (23) for absorbing aggressive gases above said space (12) and at the other side by the sides of one or more further elements (23). Through the filter elements (23) air is permitted to flow from said one sides to the opposite sides of the filter elements, which latter sides define with the opposite partition and the opposite side wall of the casing respectively two passageways which throughout their lengths are in open communication with a space between the rear wall (4) of the casing and the rear walls of the filter elements (23), in which space the outlet (30) provided in the rear wall (4) opens. </p> |
