Rotary screw compressor with oil drainage
AssigneeSvenska Rotor Maskiner AB
InventorArnold Englund
Life of this patent
Estimating the term…
Abstract
A rotary screw compressor has meshing male (2) and female (4) rotors operating in a working space limited by a high pressure end section (6), a low pressure end section (8) and a barrel section extending therebetween. The rotors (2, 4) have shaft extensions (22, 24, 26, 28) journalled in bearings (30, 32, 34, 36) in the end sections (6, 8). Oil is supplied to the bearing chambers (38, 40, 42, 44) for lubricating and cooling the bearings. The chambers (42, 44) in the low pressure end section (8) are drained to the working space through a first channel (50) and a first opening (52) in the walls (16) of the working space, and the chambers (38, 40) in the high pressure end section (6) are drained to the working space through a second channel (46) and a second opening (48) in the walls (16) of the working space.
Claims13
Rotary screw compressor for a gaseous working fluid, comprising:
- a male rotor (2) and a female rotor (4) mounted in a casing, said casing including a high pressure end section (6), a low pressure end section (8) and a barrel section (10) extending therebetween;
- said casing forming a working space therein which is generally in the shape of two intersecting parallel bores surrounded by walls including a barrel wall (16) and opposite end walls (12, 14), each of said bores of said working space housing one of said rotors;
- PG,13
- each of said male and female rotors (2, 4) having helical (66, 68) and intervening grooves (70, 72) through which the rotors intermesh, thereby forming chevron-shaped compression chambers, limited by leading and trailing lobes, in said working space;
- said causing further having a inlet port (18) and an outlet port (20) communicating with said working space;
- each of said rotors having shaft extensions (22, 24, 26, 28) mounted in bearings (30, 32, 34, 36) in said end sections (6, 8) and extending into first chambers (42, 44) in the low pressure end section (8) of the casing and into second chambers (38, 40) in the high pressure section (6) of the casing, said low pressure end section (8) having means (56) for supplying liquid to said first chambers (42, 44) and said high pressure end section (6) having means (54) for supplying liquid to said second chambers (38, 40);
- first drainage means (50) coupling said first chambers (42, 44) to a first opening (52) in a wall (16) of said working space for drainage of liquid from said first chambers (42, 44);
- and
- second drainage means (46) coupling said second chambers (38, 40) to a second opening (48) in a wall (16) of said working space for drainage of liquid from said second chambers (38, 40);
- said first opening (52) facing a compression chamber in said working space in an area where said compression chamber is in a position in which the trailing lobes of the compression chamber have passed the corresponding closing edges (86a, 86b) of the inlet port (18), so that the compression chamber has been cut off from communication with the inlet port (18);
- and
- said second opening (48) facing a compression chamber in said working space in an area in which the pressure is higher than in the compression chamber which said first opening (52) is facing.
Dependencies are inferred from the claim text.