Compressor element with improved oil injector
A compressor element ( 1 ) comprising at least one compression member ( 2 ), a housing ( 3 ) and a rotatable shaft ( 4 ) rotatably connecting the at least one compression member ( 2 ) to the housing ( 3 ), wherein at least one intermediate element ( 5 ) is provided between the rotatable shaft ( 4 ) and the housing ( 3 ) for facilitating rotation of the rotatable shaft ( 4 ), wherein the compressor element ( 1 ) further comprises at least one oil injector ( 6 ) extending from an inlet port ( 7 ) to at least one nozzle ( 8 a, 8 b, 8 c ) via an oil channel ( 9 ), wherein the oil channel ( 9 ) is shaped to allow a substantially primary flow of oil through the channel ( 9 ) for cooling of the at least one intermediate element ( 5 ).
1. A compressor element ( 1 ) comprising at least one compression member ( 2 ), a housing ( 3 ) and a rotatable shaft ( 4 ) rotatably connecting the at least one compression member ( 2 ) to the housing ( 3 ), wherein at least one intermediate element ( 5 ) comprising at least one of a roller bearing and a gear is provided between the rotatable shaft ( 4 ) and the housing ( 3 ) for facilitating rotation of the rotatable shaft ( 4 ), wherein the compressor element ( 1 ) further comprises at least one oil injector ( 6 ) extending from an inlet port ( 7 ) to at least one nozzle ( 8 a , 8 b , 8 c ) via an oil channel ( 9 ), wherein the oil channel ( 9 ) is shaped with a radius of curvature ( 20 ) larger than 5 mm to allow a flow of oil through the channel ( 9 ) for cooling of the at least one intermediate element ( 5 ) which is aligned with a direction determined by a centre line of the oil channel ( 9 ).
2. The compressor element according to claim 1 , wherein the flow has a Dean number smaller than 75, wherein the Dean number is determined by the formula
De
=
R
e
·
D
n
2
·
r
wherein Re represent a Reynolds number of the flow of oil; wherein D n represents an inner diameter of the channel ( 9 ); and wherein r represents a radius of curvature ( 20 ) of the channel ( 9 ) or a portion thereof.
3. The compressor element according to claim 1 , wherein an oil channel ( 9 ) comprises at least two nozzles ( 8 a , 8 b ).
4. The compressor element according to claim 1 , wherein the oil channel ( 9 ) is branched ( 9 a , 9 b , 9 c ).
5. The compressor element according to claim 1 , wherein the radius of curvature ( 20 ) of the oil channel ( 9 ) is larger than 10 mm.
6. The compressor element according to claim 1 , wherein the at least one oil injector ( 6 ) is arranged on the housing ( 3 ) at a distance from the at least one intermediate element ( 5 ) and wherein the at least one oil nozzle ( 8 a , 8 b , 8 c ) is biased towards the at least one intermediate element ( 5 ) and is configured to eject oil from the at least one oil nozzle ( 8 a , 8 b , 8 c ), wherein the ejected oil is adapted to impact an injection location ( 10 ), wherein an area of the injection location ( 10 ) is smaller than 10 mm 2 .
7. The compressor element according to claim 1 , wherein an oil seal ( 11 ) is arranged between the compression member ( 2 ) and the at least one intermediate element ( 5 ).
8. The compressor element according to claim 1 , wherein the housing ( 3 ) comprises a compression chamber ( 14 ) and a driving section ( 15 ) separated by a separation wall ( 23 ); wherein the compression chamber ( 14 ) comprises the at least one compression member ( 2 ) and the driving section ( 15 ) comprises the at least one intermediate element ( 5 ) and wherein the rotatable shaft ( 4 ) extends through the separation wall ( 23 ).
9. The compressor element according to claim 6 , wherein the oil seal ( 11 ) is arranged in the separation wall ( 23 ).
10. A method for manufacturing a compressor element ( 1 ) comprising at least one compression member ( 2 ), a housing ( 3 ) and a rotatable shaft ( 4 ) rotatably connecting the at least one compression member ( 2 ) to the housing ( 3 ), the method comprises providing at least one intermediate element ( 5 ) comprising at least one of a roller bearing and a gear between the rotatable shaft ( 4 ) and the housing ( 3 ) for facilitating rotation of the rotatable shaft ( 4 ), the method further comprises providing the compressor element ( 1 ) with at least one oil injector ( 6 ) extending from an inlet port ( 7 ) to at least one nozzle ( 8 a , 8 b , 8 c ) via an oil channel ( 9 ), wherein the method further comprises:
shaping the oil channel ( 9 ) with a radius of curvature ( 20 ) larger than 5 mm to allow a flow of oil through the channel ( 9 ) for cooling of the at least one intermediate element ( 5 ) which is aligned with a direction determined by a centre line of the oil channel ( 9 ).
11. The method according to claim 10 , wherein the oil channel ( 9 ) is shaped to allow the flow with a Dean number smaller than 75, wherein the Dean number is determined by the formula
De
=
R
e
·
D
n
2
·
r
wherein Re represent a Reynolds number of the flow of oil; wherein D n represents an inner diameter of the channel ( 9 ); and wherein r represents a radius of curvature ( 20 ) of the channel ( 9 ) or a portion thereof.