A variable displacement compressor in a refrigeration cycle of an air conditioning system for an automotive vehicle has a swash plate (17) provided for converting a rotary movement of the drive shaft into a linear motion of the pistons. The swash plate is fixedly mounted on the boss section (15) of the journal (14) and has an internal thread (18) which is engaged with the external thread (16) of the boss section. The swash plate includes a generally cylindrical thick central section (25) having the internal thread, and a peripheral section (26) integral with the central section and having an axial dimension smaller than the central section. A plurality of tool engaging grooves (27) are formed at least in the central section and located concentrically on the rear side (S1) surface of the swash plate. Additionally, a plurality of seat projections (28) are formed on the opposite surface (S2) to provide for sufficient cross section for the machining of the grooves.