Abstract: A compressor or vacuum pump including: —a casing having a cooling gas inlet and a cooling gas outlet for allowing a cooling gas to flow therethrough; —a fan mounted at the cooling gas inlet, including a fan housing and configured to blow said cooling gas into said casing; —a compression or vacuum chamber including a first housing, a process gas inlet and outlet for allowing a process gas to flow therethrough and at least one rotating element; —a driving module including a second housing and at least one bearing for supporting said at least one rotating element; —a silencer including a cover and configured to attenuate noise generated by the compressor or vacuum pump. The silencer includes a recess structure on its cover, configured to deflect the cooling gas flow from the fan towards the driving module.

Abstract: Housing for channelling the airflow of a radial fan of an air-cooled scroll compressor, whereby this housing is formed by a volute with an outlet and an outlet bend-connecting thereto with an included angle, whereby the included angle is an acute angle that extends from one side of the median plane defined by the axis of the inlet and the centre of the output of the outlet bend to the other side of the median plane located on the side of the end point of the transverse wall and up to a distance from this median plane.