Compressor device

1. A compressor device, comprising:

a compressor element ( 2 ) with an inlet ( 5 ) for supplying gas and an outlet ( 6 ) for discharging compressed gas,

a magnet-assisted motor ( 3 ) provided with a motor housing ( 10 ) in which a motor stator ( 11 ) is installed and a motor rotor ( 12 ) is rotatably installed in the motor stator ( 11 ), wherein the motor stator ( 11 ) is provided with windings ( 13 ) and wherein the motor housing ( 10 ) is provided with or acts as a cooling jacket ( 17 ); and

an oil supply line ( 18 ) for injecting oil into the magnet-assisted motor ( 3 );

wherein the oil supply line ( 18 ) is connected with one or a plurality of several nozzles ( 22 ) directed at heads or axial ends ( 15 ) of the windings ( 13 ) of the motor stator ( 11 ) and with the cooling jacket ( 17 ) of the magnet-assisted motor ( 3 ) and wherein the heads or axial ends ( 15 ) of the windings ( 13 ) are covered with a protective layer ( 16 ),

wherein the oil supply line ( 18 ) branches out into two branch lines ( 25 a , 25 b ),

wherein a first branch line ( 25 a ) connects the oil supply line ( 18 ) with said nozzle or said plurality of nozzles ( 22 ) and the second branch line ( 25 b ) connects the oil supply line ( 18 ) with the cooling jacket ( 17 ), and

wherein the compressor device ( 1 ) is further provided with control means ( 26 ) for controlling the quantity of oil going to the first and second branch lines ( 25 a , 25 b ) and a controller ( 27 ) which will control said means ( 26 ).

2. The compressor device according to claim 1 , wherein the protective layer ( 16 ) is thermally conductive, electrically insulating and resistant to water and oil.

3. The compressor device according to claim 2 , wherein the protective layer comprises an epoxy resin.

4. The compressor device according to claim 1 , wherein there are a plurality of nozzles and the plurality of nozzles ( 22 ) are located at one or more of the following locations in the motor housing ( 10 ):

at axial ends ( 23 ) of the motor stator ( 11 ) and the motor rotor ( 12 ), wherein the nozzles ( 22 ) are directed axially,

at a side, through a wall ( 24 ) of the cooling jacket ( 17 ) of the motor housing ( 10 ), wherein the nozzles ( 22 ) are directed radially.

5. The compressor device according to claim 1 , wherein the compressor device ( 1 ) is further provided with measuring means ( 29 ) to determine the temperature of the heads or axial ends ( 15 ) of the windings ( 13 ) of the motor stator ( 11 ) and the controller ( 27 ) is provided with an algorithm for controlling the control means ( 26 ) on the basis of the temperature of the heads or axial ends ( 15 ) of the windings ( 13 ) of the motor stator ( 11 ).

6. The compressor device according to claim 5 , wherein said algorithm is such that the controller ( 27 ) will control said control means ( 26 ) in such a way that no oil will flow to the first branch line ( 25 a ) when the temperature of the heads or axial ends ( 15 ) of the windings ( 13 ) is lower than a preset maximum temperature T ax .

7. The compressor device according to claim 1 , wherein the protective layer ( 16 ) extends over an entirety of the windings or over an entirety of the motor stator ( 11 ).

8. The compressor device according to claim 1 , wherein at least the heads or axial ends ( 15 ) of the windings ( 13 ) are encapsulated in the protective layer.

9. The compressor device according to claim 1 , wherein the oil supply line ( 18 ) is part of an oil circuit ( 19 ) which is also part of the compressor device ( 1 ), wherein the oil circuit ( 19 ) is designed in such a manner that all the oil is first directed to the magnet-assisted motor ( 3 ) and then to compressor element ( 2 ).

10. The compressor device according to claim 1 , wherein the motor stator ( 11 ) is provided with axially oriented grooves ( 30 ) or channels and/or wherein the motor housing ( 10 ), at the location of the motor stator ( 11 ), is provided with axially oriented grooves ( 30 ) or channels.

11. The compressor device according to claim 1 , wherein the nozzle or the plurality of nozzles ( 22 ) atomize the oil.

12. The compressor device according to claim 1 , wherein the magnet-assisted motor ( 3 ) is a permanent magnet motor ( 3 ).

13. The compressor device according to claim 1 , wherein the compressor element ( 2 ) is a screw compressor element ( 2 ).

14. The compressor device according to claim 1 , wherein the compressor device ( 1 ) is a vertical compressor device ( 1 ), wherein the motor rotor ( 12 ) of the magnet-assisted motor ( 3 ) extends in an axial direction (X-X′) vertically positioned in normal compressor device operation ( 1 ), wherein the magnet-assisted motor ( 3 ) forms a head or upper part of the compressor device ( 1 ) and the compressor element ( 2 ) forms a base or lower part of the compressor device ( 1 ).