Method for controlling the supply of oil to an internal combustion engine

Abstract

Method for controlling the supply of oil to an internal combustion engine, comprising a procedure for detecting a potentially dangerous condition for the correct operation of an internal combustion engine (1). Said condition is the clogging of an oil filter (3) upstream of the engine (1) or the excessive presence of fuel in the lubricant oil. The detection procedure comprises the steps of: changing the flow rate of oil that transits through the filter (3) and that is processed by a pump (2) for lubricating the engine (1); detecting the time that passes between changing the oil flow rate and a detection of a pre-established variation in a parameter connected at least with the pressure downstream of said filter (3), said variation being determined by said change of the flow rate, said filter (3) being placed upstream of the engine (1); comparing said time with pre-established values.

1 . A method for controlling the supply of oil to an internal combustion engine to detect a potentially dangerous condition for the correct operation of the internal combustion engine ( 1 ), the potentially dangerous condition for correct operation of the internal combustion engine ( 1 ) being clogging of an oil filter ( 3 ) upstream of the engine ( 1 ) or excessive presence of fuel in the oil, said method comprising the steps of:
 changing a flow rate of oil that transits through the filter ( 3 ) and that is processed by a pump ( 2 ) for lubricating the engine ( 1 );   detecting a time that passes between changing the oil flow rate and a detection of a pre-established variation in a parameter connected at least with a pressure downstream of said filter ( 3 ), said variation being determined by the change of the flow rate; and   comparing said time with pre-established values.   
     
     
         2 . The method according to  claim 1 , characterized in that said parameter connected with the pressure downstream of the filter ( 3 ) is a pressure difference between downstream and upstream of the filter ( 3 ). 
     
     
         3 . The method according to  claim 1 , characterized in that the step of changing the oil flow rate includes varying a capacity of the pump ( 2 ). 
     
     
         4 . The method according to  claim 1 , characterized in that the step of changing the oil flow rate includes varying a number of revolutions of the pump ( 2 ). 
     
     
         5 . The method according to  claim 1 , further comprising a step of activating a reduction cycle of a level of fuel contamination in the oil; said cycle comprising the step of heating the oil, which brings about the evaporation of fuel present in the oil. 
     
     
         6 . The method according to  claim 5 , characterized in that the step of heating the oil brings about heating of fluid present in an oil sump ( 6 ) from which the oil is taken by the pump ( 2 ) and in which the oil is recirculated after passing into the engine ( 1 ); the evaporation of the fluid present in the oil sump causing evaporated fuel to be conveyed into a combustion chamber ( 10 ) of the engine through an oil separator  5  ( 7 ) and a fuel suction system ( 8 ). 
     
     
         7 . The method according to  claim 5 , characterized in that the pump ( 2 ) in a first operating method has a mapping that includes a first value for the maximum capacity; the step of heating the oil comprises the step of making the pump ( 2 ) operate in a second operating mode in which the pump assumes a higher maximum capacity than the maximum capacity of in the first operating mode. 
     
     
         8 . The method according to  claim 5 , characterized in that the step of heating the oil comprises a step of opening a conduit connecting downstream and upstream of the pump ( 2 ) so that a part of the oil flow bypasses the engine ( 1 ). 
     
     
         9 . The method according to  claim 1 , characterized in that if during the step of comparing said time with the pre-established values a fault is reported, a report is transmitted:
 to an internal instrument inside a passenger compartment of a vehicle driven by the engine ( 1 ); or   to a remote memory space to which access is possible via internet.   
     
     
         10 . The method according to  claim 1 , further comprising a procedure for tracking the successful change of the oil filter ( 3 ), the procedure comprising the steps of:
 periodically detecting through a sensor ( 9 ) the pressure downstream of the filter ( 3 ) ;   retroactively adjusting at least a first operating parameter of the pump ( 2 ) maintaining the parameter on values that allow the pressure detected by the sensor ( 9 ) to be maintained within a prefixed range regardless of a degree of clogging of the filter;   monitoring a trend over time of the values of said at least one first parameter that allow the pressure detected by the sensor ( 9 ) to be maintained within a prefixed range regardless of the degree of clogging of the filter and to identify a variation of said values that is greater than a pre-established threshold in a range of time lower than a pre-established limit; and   recording in memory means ( 4 ) associated with a control unit ( 5 ) a successful replacement of the filter ( 3 ) upon the detection of said variation over a pre-established threshold.