Lift pump system for a direct injection fuel system
First Claim
Patent Images
1. A system for delivering fuel directly to a cylinder of an internal combustion engine, the system comprising:
- a fuel lift pump supplying fuel to an injection pump;
a fuel line coupling an output of said fuel lift pump to an inlet of said injection pump;
an accumulator coupled to the fuel line and between the output of said lift pump and the inlet of said injection pump; and
a controller that adjusts energy supplied to said lift pump such that a pressure at an outlet of the accumulator is above a first predetermined amount and wherein said controller stops energy supplied to said fuel lift pump when said pressure at the outlet of the accumulator is greater than a second predetermined amount.
1 Assignment
0 Petitions
Accused Products
Abstract
An economical method for controlling a lift pump operating as part of a direct injection fuel system is described. According to the method, the lift pump is operated at efficient operating conditions and then stopped until additional fuel is requested.
59 Citations
25 Claims
-
1. A system for delivering fuel directly to a cylinder of an internal combustion engine, the system comprising:
-
a fuel lift pump supplying fuel to an injection pump; a fuel line coupling an output of said fuel lift pump to an inlet of said injection pump; an accumulator coupled to the fuel line and between the output of said lift pump and the inlet of said injection pump; and a controller that adjusts energy supplied to said lift pump such that a pressure at an outlet of the accumulator is above a first predetermined amount and wherein said controller stops energy supplied to said fuel lift pump when said pressure at the outlet of the accumulator is greater than a second predetermined amount. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A system for delivering fuel directly to a cylinder of an internal combustion engine, the system comprising:
-
a first electrically driven fuel pump supplying fuel to a second mechanically driven fuel pump; a fuel line fluidly coupling an output of said first electrically driven fuel pump to an inlet of said second mechanically driven fuel pump; an accumulator coupled to the fuel line and between the output of said first fuel pump and the inlet of said second mechanically driven fuel pump; and a controller that supplies current to said first fuel pump to when the efficiency of said second mechanically driven fuel pump is less than a predetermined amount and wherein said controller stops current flow to said first fuel pump when the efficiency of said second mechanically driven fuel pump is greater than a predetermined amount. - View Dependent Claims (11, 12, 13, 14, 15)
-
-
16. A method to deliver fuel to a cylinder of an internal combustion engine, the method comprising:
-
combusting fuel in at least a cylinder of said internal combustion engine; operating an electrically driven fuel pump in a first mode to deliver said fuel from a fuel source to an accumulator and a mechanically driven fuel pump, the accumulator coupled to a fuel line, the fuel line coupling an inlet of said mechanically driven fuel pump to an outlet of said electrically driven fuel pump, while said engine is combusting said fuel, said electrically driven fuel pump being activated in said first mode when fuel pressure at an outlet of the accumulator is below a predetermined level, said electrically driven fuel pump being deactivated in said first mode when fuel pressure at the outlet of the accumulator is above a predetermined level; operating a mechanically driven fuel pump to deliver fuel from said mechanically driven fuel pump to at least a fuel injector; and injecting fuel from said at least a fuel injector directly into said cylinder of said internal combustion engine. - View Dependent Claims (17, 18, 19, 20)
-
-
21. A method to deliver fuel to a cylinder of an internal combustion engine, the method comprising:
-
combusting fuel in at least a cylinder of said internal combustion engine; operating a first fuel pump in a first mode when the amount of fuel being delivered to said internal combustion engine is less than a first amount, said first mode comprising delivering said fuel from an accumulator to a second fuel pump during said combustion, said accumulator coupled to a fuel line, the fuel line coupling an outlet of said first fuel pump to an inlet of said second fuel pump and said first fuel pump being activated in said first mode when a fuel pressure at an outlet of the accumulator is below a predetermined level, said first fuel pump being deactivated in said first mode when the fuel pressure at the outlet of the accumulator is above a predetermined level; and operating said first fuel pump in a second mode when the amount of fuel being delivered to said internal combustion engine is greater than said first amount, said second mode comprising delivering said fuel from said fuel source to said second fuel pump while there is combustion occurring during a cycle of said at least a cylinder, said first fuel pump being supplied a varying voltage without the speed of said fuel pump going to zero. - View Dependent Claims (22, 23, 24, 25)
-
Specification