ADAPTIVE FUEL DIRECT INJECTION SYSTEM
First Claim
1. A direct fuel injection system including a common rail (4) including a control unit (1), a pump (2) and a valve (3), controlled on an on or off basis by the control unit (1), in order to regulate the volume of fuel sent to the pump (2) to be fed into the common rail (4), said control unit (1) comprisingfirst determination means (40) adapted to determine a first variable (a peak phase duration (27)) during which a command must be applied to the valve (3) in order to obtain a first objective variable (a peak current (38, 60)) greater than or equal to a reference value (a reference peak current (61)) necessary to cause a change of state of the valve (3),second determination means (70) adapted to determine a second variable (a holding ratio (28)) in accordance with which a command must be applied to the valve (3), after its change of state, in order to maintain a second objective variable (a holding current (39, 90)) greater than or equal to a reference value (a reference holding current (91)) necessary to maintain said state of the valve (3),application means adapted to apply said command to said valve (3) first continuously during said peak phase duration (27) and then by pulse width modulation in accordance with said holding ratio (28),adaptation means (42, 72) for the first variable (27) and/or the second variable (28), these adaptation means (42, 72) being recurrent and automatic for said variable (27, 28),characterized in that said adaptation means (42, 72) are adapted to calculate a coefficient of modulation (42, 73) and to apply it as a multiplier to the variable (27, 28) in order to correct it.
3 Assignments
0 Petitions
Accused Products
Abstract
A direct fuel injection system including a common rail and control unit, a pump, an on/off valve, controlled by the control unit, to regulate the volume of fuel sent to the pump to be fed into the common rail, the control unit including: first determination elements for determining a peak phase duration during which a command must be applied to the valve to obtain a peak current to cause a change of state of the valve; second determination elements for determining a holding ratio according to which a command must be applied to the valve, after its change of state, to maintain a holding current necessary to maintain the state of the valve; application elements for applying the command to the valve first continuously during the peak phase duration and then by pulse width modulation according to the holding ratio; and at least one recurrent and automatic adaptation element.
-
Citations
8 Claims
-
1. A direct fuel injection system including a common rail (4) including a control unit (1), a pump (2) and a valve (3), controlled on an on or off basis by the control unit (1), in order to regulate the volume of fuel sent to the pump (2) to be fed into the common rail (4), said control unit (1) comprising
first determination means (40) adapted to determine a first variable (a peak phase duration (27)) during which a command must be applied to the valve (3) in order to obtain a first objective variable (a peak current (38, 60)) greater than or equal to a reference value (a reference peak current (61)) necessary to cause a change of state of the valve (3), second determination means (70) adapted to determine a second variable (a holding ratio (28)) in accordance with which a command must be applied to the valve (3), after its change of state, in order to maintain a second objective variable (a holding current (39, 90)) greater than or equal to a reference value (a reference holding current (91)) necessary to maintain said state of the valve (3), application means adapted to apply said command to said valve (3) first continuously during said peak phase duration (27) and then by pulse width modulation in accordance with said holding ratio (28), adaptation means (42, 72) for the first variable (27) and/or the second variable (28), these adaptation means (42, 72) being recurrent and automatic for said variable (27, 28), characterized in that said adaptation means (42, 72) are adapted to calculate a coefficient of modulation (42, 73) and to apply it as a multiplier to the variable (27, 28) in order to correct it.
Specification