Abstract: The scroll compressor (1) includes a fixed scroll (7); an orbiting scroll (8); a drive shaft (16); a support arrangement (5) including a thrust bearing surface (9) on which is slidably mounted the orbiting scroll (8); a rotation preventing device configured to prevent rotation of the orbiting scroll (8) with respect to the fixed scroll (7), the rotation preventing device including orbital discs (28) respectively arranged in circular receiving holes (29) provided on the support arrangement (5), each orbital disc (28) being provided with an outer circumferential bearing surface (31) cooperating with an inner circumferential bearing surface (32) of the respective circular receiving hole (29); and a lubrication system configured to lubricate the inner and outer circumferential bearing surfaces (32, 31) with oil supplied from an oil sump (50), the lubrication system including lubrication passages (41) formed within the support arrangement (5), each lubrication passage (41) including an oil outlet aperture (41.

Abstract: The fluid machine includes a stationary member (6), a rotary member (5) and a labyrinth seal (9) including a succession of stationary steps (11) formed on the stationary member (6), and a succession of rotary steps (14) formed on the rotary member (5). The labyrinth seal (9) further includes a plurality of stationary recesses (18) each formed in a radial wall portion (12) of a respective stationary step (11), and a plurality of rotary recesses (21) each formed in a radial wall portion (16) of a respective rotary step (14). Each stationary step (11) defines a stationary projection (19) delimited by the stationary recess (18) formed on said stationary step (11), and each rotary step (14) defines a rotary projection (22) delimited by the rotary recess (21) formed on said rotary step (14). The axial width (Wr) of each of the stationary recesses (18) and of the rotary recesses (21) substantially equals the axial width (Wp) of each of the stationary projections (19) and of the rotary projections (22).

Abstract: The centrifugal compressor includes an hermetic housing; a drive shaft (4); a first and a second compression stage (8, 9) configured to compress a refrigerant, the first and second compression stages (8, 9) respectively including a first and a second impeller (18, 19), the first and second impellers (18, 19) being connected to the drive shaft (4) and being arranged in a back-to-back configuration; a radial annular groove (27) formed between the back-sides (25, 26) of the first and second impellers (18, 19); an inter-stage sealing arrangement (35) provided between the first and second compressor stages (8, 9) and in the radial annular groove (27); a radial bearing arrangement configured to rotatably support the drive shaft (4); and a thrust bearing arrangement configured to limit an axial movement of the drive shaft (4) during operation.

Abstract: This scroll compressor includes a scroll compression unit including a first fixed scroll including a first fixed base plate and a first fixed spiral wrap, an orbiting scroll arrangement (7) including a first orbiting spiral wrap (14), the first fixed spiral wrap and the first orbiting spiral wrap (14) forming a plurality of first compression chambers. The scroll compressor further includes a refrigerant suction part suitable for supplying the scroll compression unit with refrigerant to be compressed. The orbiting scroll arrangement (7) further includes a first orbiting guiding portion (21) extending from an outer end portion of the first orbiting spiral wrap (14) and configured to guide, in use, at least a part of the refrigerant supplied to the scroll compression unit towards the first compression chambers.