Turbine engine lubrication method and system

Abstract

A method and a system for lubricating a turbomachine including an oil tank, an oil feed pump, an oil/air separator, and at least two enclosures closed by air flow rate seals, each including a low outlet and housing shaft-supporting rolling bearings. The method injects oil from the tank into the enclosures by the pump to lubricate the bearings, introduces compressed air at a low flow rate into the enclosures via the seals to pressurize the enclosures, recuperates all of the air and the oil introduced into the enclosures via their low outlet, uses gravity and the pressurization of the enclosures to convey the oil/air mixture as recovered in this way to the oil/air separator, separates the oil and the air of the mixture by the oil/air separator, returns the oil to the tank, and exhausts the air to outside the turbomachine.

1 - 9 . (canceled) 
   
   
       10 . A method of lubricating a turbomachine including at least two distinct enclosures closed at their ends by low air flow rate seals, low outlets and containing rolling bearings for supporting shafts, an oil tank, an oil feed pump, and an oil/air separator, the method comprising:
 injecting oil from the tank into the enclosures by the oil feed pump to lubricate the bearings;   introducing compressed air at a low flow rate into the enclosures through the seals to pressurize the enclosures;   recuperating all of the air and the oil introduced into the enclosures via their low outlet;   using gravity and pressurization of the enclosures by the air introduced therein to convey the oil/air mixture as recovered in this way to the oil/air separator;   separating the oil and the air of the mixture by the oil/air separator, operation of the oil/air separator being controlled so as to be triggered only when oil is present at its inlet;   returning the oil to the tank; and   exhausting the air to outside the turbomachine.   
   
   
       11 . A method according to  claim 10 , further comprising controlling operation of the oil feed pump to regulate the flow rate of oil conveyed to the enclosures as a function of pressure and/or temperature inside the enclosures. 
   
   
       12 . A method according to  claim 11 , wherein the oil feed pump is started only when the temperature inside the enclosures rises above a given temperature. 
   
   
       13 . A method according to  claim 10 , further comprising cooling the oil prior to conveying the oil to the enclosures. 
   
   
       14 . A turbomachine lubrication system comprising:
 at least two distinct enclosures closed at their ends by low air flow rate seals and housing rolling bearings for supporting shafts;   an oil tank;   an oil feed pump for feeding the enclosures with lubricating oil from the tank;   means for introducing compressed air at a low flow rate into the enclosures through the seals to pressurize the enclosures;   means for recovering, under gravity and under effect of the enclosures being pressurized, all of the air and the lubricating oil introduced into the enclosures;   an oil/air separator for separating the oil and the air of the mixture;   means for controlling the operation of the oil/air separator;   means for returning the oil to the tank; and   means for exhausting the air to outside the turbomachine.   
   
   
       15 . A system according to  claim 14 , further comprising means for controlling operation of the oil feed pump. 
   
   
       16 . A system according to  claim 14 , wherein the oil/air separator includes a pumping function to assist sucking the oil/air mixture recovered from the enclosures and returning the oil to the tank. 
   
   
       17 . A system according to  claim 14 , wherein the oil feed pump and/or the oil/air separator are electrically driven. 
   
   
       18 . A turbomachine, comprising a lubrication system according to  claim 14 .