OIL CIRCUIT, OIL-FREE COMPRESSOR PROVIDED WITH SUCH OIL CIRCUIT AND A METHOD TO CONTROL LUBRICATION AND/OR COOLING OF SUCH OIL-FREE COMPRESSOR VIA SUCH OIL CIRCUIT

摘要

Oil circuit for lubrication and cooling of an oil-free compressor (1)comprising a motor (4) with a variable speed anda compressor element (2) driven by said motor (4), - whereby this oil circuit(5) is provided with an oil reservoir (10) with oil (11)and a rotary oil pump (13) configured to drive oil (11) from the oil reservoir(10) through an inlet channel (23) upstream the rotaryoil pump (13) to the compressor element (2) and/or the motor (4) via an oilpipe (12); - whereby this rotary oil pump (13) is providedwith a rotor (26) mounted on a rotation shaft (27), whereby this rotary oilpump (13) has a swept volume, and whereby this rotary oilpump (13) is driven by the motor (4) of the compressor element (2); - wherebythe oil circuit (5) is further provided with a return pipe(19) configured to guide oil (11) from the compressor element (2) and/or themotor (4) back to the oil reservoir (10); - whereby the oilcircuit (5) is further provided with a bypass pipe (15) and a pressure-actuated bypass valve (14) which are configured to directly guidea portion of the oil (11) between the rotary oil pump (13) and the compressorelement (2) and/or the motor (4) back to the oil reservoir(10) without this portion of the oil (11) passing through the compressorelement (2) and/or the motor (4) during its way back to the oilreservoir (10); and - whereby the oil circuit (5) is further provided with anoil cooler (16), characterised in that the oil cooler (16) isplaced in the bypass pipe (15) and that the bypass valve (14) is placed in theoil pipe (12).