Abstract: A scroll compressor (2) includes a sealed housing (3); a compression unit (11), having a fixed scroll (12) and an orbiting scroll (13); a drive shaft (18) configured to drive the orbiting scroll (13) to move orbitally, the drive shaft (18) being capable of rotating about an axis of rotation; a synchronous reluctance motor (15) configured to drive the drive shaft (18) to rotate about the axis of rotation, the synchronous reluctance motor (15) comprising a rotor (16) coupled to the drive shaft (18) and a stator (17) disposed around the rotor (16), and the rotor (16) including a ferrite permanent magnet (23); a compressor control apparatus (31) configured to control the scroll compressor (2) to operate; a lubricating oil tank (27), formed in a bottom portion of the sealed housing (3); a heating apparatus configured to heat lubricating oil stored in the lubricating oil tank (27); and an oil temperature sensor (28) disposed in the lubricating oil tank (27).

Abstract: A scroll compressor including a hermetic casing provided with a suction inlet; a compression unit; a drive shaft configured to drive an orbiting scroll of the compression unit in an orbital movement; an electric motor coupled to the drive shaft; an oil sump; a refrigerant guiding device configured to force a main part of a refrigerant, entering the scroll compressor through the suction inlet, to flow downwardly through the electric motor, before reaching the compression unit; and an oil sump fairing arranged between a lower end of the electric motor and a free surface of oil stored in the oil sump, the oil sump fairing being configured to prevent a refrigerant flow, emerging from the lower end of the electric motor, to directly impact the free surface of the oil stored in the oil sump.

Abstract: A scroll compressor (2) includes a sealed housing (3); a compression unit (11), having a fixed scroll (12) and an orbiting scroll (13); a drive shaft (18) configured to drive the orbiting scroll (13) to move orbitally, the drive shaft (18) being capable of rotating about an axis of rotation; a synchronous reluctance motor (15) configured to drive the drive shaft (18) to rotate about the axis of rotation, the synchronous reluctance motor (15) comprising a rotor (16) coupled to the drive shaft (18) and a stator (17) disposed around the rotor (16), and the rotor (16) including a ferrite permanent magnet (23); a compressor control apparatus (31) configured to control the scroll compressor (2) to operate; a lubricating oil tank (27), formed in a bottom portion of the sealed housing (3); a heating apparatus configured to heat lubricating oil stored in the lubricating oil tank (27); and an oil temperature sensor (28) disposed in the lubricating oil tank (27).

Abstract: A method for managing oil in a running multi-compressor refrigeration system including a controller and a multi-compressor device, includes monitoring an oil level in the oil sump of each compressor through the respective oil level detection device; detecting that a lack of oil situation occurs in a running compressor, if the oil level in said running compressor reaches a predetermined threshold condition; performing an oil managing action if a lack of oil situation is detected for a running compressor, the oil managing action being based on a changing of ON/OFF configurations of the compressors in the multi-compressor device and including performing an oil balancing action, if more than a half of the total number of compressors are running, or performing an oil returning action, if a half or less of the total number of compressors are running.

Abstract: A scroll compressor (2) includes a sealed housing (3); a compression unit (11), having a fixed scroll (12) and an orbiting scroll (13); a drive shaft (18) configured to drive the orbiting scroll (13) to move orbitally, the drive shaft (18) being capable of rotating about an axis of rotation; a synchronous reluctance motor (15) configured to drive the drive shaft (18) to rotate about the axis of rotation, the synchronous reluctance motor (15) comprising a rotor (16) coupled to the drive shaft (18) and a stator (17) disposed around the rotor (16), and the rotor (16) including a ferrite permanent magnet (23); a compressor control apparatus (31) configured to control the scroll compressor (2) to operate; a lubricating oil tank (27), formed in a bottom portion of the sealed housing (3); a heating apparatus configured to heat lubricating oil stored in the lubricating oil tank (27); and an oil temperature sensor (28) disposed in the lubricating oil tank (27).

Abstract: The scroll compressor includes a compression unit; a drive shaft which is vertically orientated; a lower bearing arrangement (28) configured to rotatably support the drive shaft; and an oil pump (29) arranged at a lower end of the drive shaft and configured to deliver oil to the compression unit and to the lower bearing arrangement (28). The lower bearing arrangement (28) comprises a radial bearing housing (34) including an inner radial bearing surface (37) surrounding the lower end portion of the drive shaft; upper and lower axial thrust bearings (43, 44) configured to limit an axial movement of the drive shaft; and a pressurized oil chamber (51) fluidly connected to the oil pump (29), the pressurized oil chamber (51) being at least partially delimited by the outer surface of the lower end portion of the drive shaft, the inner radial bearing surface (37) and the upper and lower axial thrust bearings (43, 44).

Abstract: The scroll compressor (1) includes a compression unit (6); a drive shaft (16) which is vertically orientated; upper and lower bearing arrangements (27, 28) configured to rotatably support the drive shaft (16); a centrifugal oil pump (29) including a pick-up tube (32) attached to a lower end portion (23) of the drive shaft (16) and provided with a oil inlet immersed in an oil sump (31), the centrifugal oil pump (29) being configured to deliver oil to the compression unit (6) and to the upper and lower bearing arrangements (27, 28); and a static fairing member (35) secured to a non-rotating part of the scroll compressor (1) and including a static tubular part (36) which is immersed in the oil sump (31) and which surrounds the pick-up tube (32) with a predetermined distance such that a gap is formed between the inner surface of the static tubular part (36) and the outer surface of the pick-up tube (32).

Abstract: The multi-compressor system (7) has a plurality of parallelly coupled compressors (8); inlet connection lines (15) each connected to a refrigerant suction fitting of a respective compressor (8); outlet connection lines (17) each connected to a refrigerant discharge fitting of a respective compressor (8); a common oil balancing line (18) and balancing connection lines (19) each connecting the common oil balancing line (18) to an oil balancing connection (21) of a respective compressor (8); and spring-loaded normally-open valves (25) each being arranged within a respective balancing connection line (19) or within an oil balancing connection (21) of a respective compressor (8) and each being configured to close when a pressure difference between a pressure prevailing in the low pressure volume of the respective compressor (8) and a pressure prevailing in the common oil balancing line (18) reaches a predetermined value.

Abstract: The scroll compressor (1) includes a compression unit (6); a drive shaft (16) which is vertically orientated; upper and lower bearing arrangements (27, 28) configured to rotatably support the drive shaft (16); a centrifugal oil pump (29) including a pick-up tube (32) attached to a lower end portion (23) of the drive shaft (16) and provided with a oil inlet immersed in an oil sump (31), the centrifugal oil pump (29) being configured to deliver oil to the compression unit (6) and to the upper and lower bearing arrangements (27, 28); and a static fairing member (35) secured to a non-rotating part of the scroll compressor (1) and including a static tubular part (36) which is immersed in the oil sump (31) and which surrounds the pick-up tube (32) with a predetermined distance such that a gap is formed between the inner surface of the static tubular part (36) and the outer surface of the pick-up tube (32).

Abstract: The scroll compressor (2) includes a hermetic casing (3) comprising a mid shell (4) provided with a suction inlet (7); a compression unit (11) arranged within the hermetic casing (3); a drive shaft (27) configured to drive an orbiting scroll (13) of the compression unit (11); an electric motor (21) coupled to the drive shaft (27) and configured to drive in rotation the drive shaft (27) about its rotational axis, the electric motor (21) including a rotor (22) and a stator (23) which includes a stator stack (24), wherein the stator stack (24) is press-fitted in the mid shell (4), the suction inlet (7) is facing the stator stack (24), and the compression unit (11) includes a single suction opening (34) arranged at an opposite position in relation to the suction inlet (7).

Abstract: The centrifugal turbo-compressor (2) includes a hermetic casing (3); a drive shaft (6) having a longitudinal axis and rotatably arranged within the hermetic casing (3); a compression stage including an impeller (17) connected to the drive shaft (6); a gas suction inlet (42); and a gas flow path (P) fluidly connected to the gas suction inlet (42) and configured to supply the compression stage with a gas flow. The gas flow path (P) includes a relaxation chamber (46) at least partially surrounding the drive shaft (6), the gas suction inlet (42) emerging substantially radially into the relaxation chamber (46); and a plurality of inlet flow guide channels (51) fluidly connected to the relaxation chamber (46) and angularly distributed around the longitudinal axis of the drive shaft (6), the inlet flow guide channels (51) extending radially towards the drive shaft (6) and being axially offset from the gas suction inlet (42) and the relaxation chamber (46).

Abstract: The refrigerant compressor includes a compressor casing (2); an oil sump (13) arranged in the compressor casing (2); and an oil level sensor arrangement (14) configured to detect an oil level in the oil sump (13), the oil level sensor arrangement (14) including a tubular element (16) secured to the compressor casing (2) and a floating element (17) surrounding the tubular element (16) and being movably mounted with respect to the tubular element (16). The compressor casing (2) includes a passage opening (24) and dimensions of the tubular element (16), the floating element (17) and the passage opening (24) are defined to allow an insertion and a removal of the tubular element (16) and the floating element (17) into and out of the compressor casing (2) through the passage opening (24).

Abstract: The bearing arrangement includes a one-piece gas bearing sleeve (32) configured to rotatably support the drive shaft (4) and made in molybdenum or in a molybdenum alloy, the one-piece gas bearing sleeve (32) including a radial bearing surface (33) configured to Surround the drive shaft (4).

Abstract: The scroll compressor (1) includes a compression unit (6); a drive shaft (16) which is vertically orientated; upper and lower bearing arrangements (27, 28) configured to rotatably support the drive shaft (16); a centrifugal oil pump (29) including a pick-up tube (32) attached to a lower end portion (23) of the drive shaft (16) and provided with a oil inlet immersed in an oil sump (31), the centrifugal oil pump (29) being configured to deliver oil to the compression unit (6) and to the upper and lower bearing arrangements (27, 28); and a static fairing member (35) secured to a non-rotating part of the scroll compressor (1) and including a static tubular part (36) which is immersed in the oil sump (31) and which surrounds the pick-up tube (32) with a predetermined distance such that a gap is formed between the inner surface of the static tubular part (36) and the outer surface of the pick-up tube (32).

Abstract: The scroll compressor includes a compression unit; a drive shaft which is vertically orientated; a lower bearing arrangement (28) configured to rotatably support the drive shaft; and an oil pump (29) arranged at a lower end of the drive shaft and configured to deliver oil to the compression unit and to the lower bearing arrangement (28). The lower bearing arrangement (28) comprises a radial bearing housing (34) including an inner radial bearing surface (37) surrounding the lower end portion of the drive shaft; upper and lower axial thrust bearings (43, 44) configured to limit an axial movement of the drive shaft; and a pressurized oil chamber (51) fluidly connected to the oil pump (29), the pressurized oil chamber (51) being at least partially delimited by the outer surface of the lower end portion of the drive shaft, the inner radial bearing surface (37) and the upper and lower axial thrust bearings (43, 44).

Abstract: The centrifugal turbo-compressor (2) includes a hermetic casing; a drive shaft (6); a first and a second compression stage (12, 13) configured to compress a refrigerant and respectively including a first and a second impeller (18, 19) connected to the drive shaft (6) and being arranged in a back-to-back configuration; an interstage sealing device provided between the first and second impellers (18, 19). The hermetic casing includes a main casing portion (4) in which are arranged the first and second compression stages (12, 13) and the inter-stage sealing device. The first and second compression stage (12, 13) respectively includes a first and a second aerodynamic member (29, 31) each having an annular disc shape and respectively facing front-sides (21, 22) of the first and second impellers (18, 19).

Abstract: The scroll compressor (2) includes a hermetic casing (3) comprising a mid shell (4) provided with a suction inlet (7); a compression unit (11) arranged within the hermetic casing (3); a drive shaft (27) configured to drive an orbiting scroll (13) of the compression unit (11); an electric motor (21) coupled to the drive shaft (27) and configured to drive in rotation the drive shaft (27) about its rotational axis, the electric motor (21) including a rotor (22) and a stator (23) which includes a stator stack (24), wherein the stator stack (24) is press-fitted in the mid shell (4), the suction inlet (7) is facing the stator stack (24), and the compression unit (11) includes a single suction opening (34) arranged at an opposite position in relation to the suction inlet (7).

Abstract: The Modular turbo compressor shaft (4) comprise a tubular bearing portion (5) having a first axial end portion and a second axial end portion; an impeller portion (6) arranged at the first axial end portion of the tubular bearing portion (5); and a driving portion (7) arranged at the second axial end portion of the tubular bearing portion (5). The tubular bearing portion (5) is made of a hard material, and the impeller portion (6) and/or the driving portion (7) are made of relatively soft material compared to the hard material of the tubular bearing portion (5). The impeller portion (6) and/or the driving portion (7) are at least partially extending into the tubular bearing portion (5) and are firmly connected to the tubular bearing portion (5).

Abstract: This scroll compressor (2) includes a first and second fixed scrolls (4, 5) comprising first and second fixed spiral wraps (9, 12), an orbiting scroll arrangement (7) comprising first and second orbiting spiral wraps (14, 15), the first fixed spiral wrap (9) and the first orbiting spiral wrap (14) forming a plurality of first compression chambers (16) and the second fixed spiral wrap (5) and the second orbiting spiral wrap (15) forming a plurality of second compression chambers (17). The scroll compressor further includes a drive shaft (23) adapted for driving the orbiting scroll arrangement (7) in an orbital movement, and a driving motor (24) arranged for driving in rotation the drive shaft (23) about a rotation axis, the driving motor (24) being located nearby the first fixed scroll (4). The first fixed scroll (4) includes at least one first discharge passage (21) arranged to conduct the refrigerant compressed in the first compression chambers (16) towards the driving motor (24).

Abstract: The axial bearing arrangement comprises a first axial bearing plate (12) and a second axial bearing plate (13) each having an annular ring shape, the first axial bearing plate (12) having a first surface (12.1) axially facing the second axial bearing plate (13) and a second surface (12.2) opposite to the respective first surface (12.1), the second axial bearing plate (13) having a first surface (13.1) axially facing the first axial bearing plate (12) and a second surface (13.2) opposite to the respective first surface (13.1); a spacer ring (14) clamped between the first surfaces (12.1, 13.1) of the first and second axial bearing plates (12, 13), the spacer ring (14) defining an axial distance between the first and second axial bearing plates (12, 13); and a bearing sleeve (15) abutting the second surface (13.2) of the second axial bearing plate (13) and being secured to a compressor block (16).