Device and method for the cleaning of lubricant and a lubricant circuit

1. In a lubricant circuit, the improvement comprising:

a cleaning device for the cleaning of a lubricant which circulates in said lubricant circuit, said cleaning device including:

an intake line connectable to the lubricant circuit through which at least a quantity of lubricant to be cleaned is fed to said cleaning device for at least partial removal of contaminants, resulting in a cleaned lubricant;

a first heat exchanger in said intake line;

a second heat exchanger in said intake line;

a return line connectable to said lubricant circuit for returning the cleaned lubricant into said lubricant circuit, said return line passing through said first heat exchanger;

a cleaning circuit in which said intake line terminates;

a feed device for circulating a mixture of a circulating lubricant contained in said cleaning circuit and the lubricant to be cleaned;

at least one cross-flow filter arranged downstream of the feed device which is provided with at least one filter membrane past which the mixture of circulating lubricant and the lubricant to be cleaned flows for filtering; and

a filtrate chamber into which a part of the mixture of circulating lubricant and the lubricant to be cleaned flows as cleaned lubricant, after passing through said filter membrane under a pressure generated by said feed device, said filtrate chamber being coupled to said return line to return the cleaned lubricant to said lubricant circuit.

2. The lubricant circuit according to claim 1 , wherein the cross-flow filter comprises at least one filter tube through which the mixture flows for filtration, the at least one filter tube having a fine-pore surface filtration layer on an inner side of the at least one filter tube.

3. The lubricant circuit according to claim 1 , wherein the cleaning circuit comprises an inlet for fresh circulating oil coupled to the cleaning circuit via an expansion vessel, and a drain provided with a valve for discharging contaminated circulating oil from the cleaning circuit.

4. The lubricant circuit according to claim 1 , further comprising a feed device in the intake line configured to deliver branched-off lubricant to be cleaned into the cleaning circuit with a predetermined delivery pressure.

5. The lubricant circuit according to claim 1 , wherein said second heat exchanger is an externally heated heat exchanger.

6. The lubricant circuit according to claim 1 , further comprising a flushing device for flushing of cross-flow filter with a flushing fluid which is coupled to the cross-flow filter via a 3-way valve and the return line.

7. The lubricant circuit according to claim 6 , wherein the flushing device comprises a vessel for the flushing fluid that is fed through the filter membrane opposite a filtration direction.

8. The lubricant circuit according to claim 1 , further comprising at least one ultrasonic probe on the cross-flow filter.

9. The lubricant circuit according to claim 1 , wherein the lubricant circuit includes at least one of an engine, a compressor or a turbocharger.

10. The lubricant circuit according to claim 1 , wherein the circulating oil in the cleaning circuit contains cleaning bodies, and wherein the feed device of the cleaning circuit is a jet pump whose drive connection is connected with a feed line, which is in flow connection with the cleaning circuit through a separator arranged downstream of the cross-flow filter, and that a pump in the feed line delivers a part of the circulating oil via the separator from the cleaning circuit for operating the jet pump.

11. The lubricant circuit according to claim 10 , wherein the intake line terminates in the jet pump.