System and method for operating a direct injection fuel pump

Patent metadata

Field	Value
Publication number	US-9297331-B2
Application number	US-201313890660-A
Country	US
Kind code	B2
Filing date	May 9, 2013
Priority date	May 9, 2013
Publication date	Mar 29, 2016
Grant date	Mar 29, 2016

Abstract

Methods and systems are provided for a direct injection fuel pump. The methods and systems selectively operate the direct injection fuel pump with varying levels of efficiency. In one example, an amount of piston lift of a direct fuel injection pump may be adjusted to selectively alter the pump's operating efficiency.

First claim

The invention claimed is:

1. A method of operating a direct injection fuel pump, comprising:
in response to engine knock,
during a first condition where the first condition is a first engine load, operating the direct injection fuel pump with a first piston lift amount;
during a second condition where the second condition is a second engine load greater than the first engine load, the second condition different from the first condition, operating the direct injection fuel pump with a second piston lift amount, the second piston lift amount greater than the first lift amount;

in the absence of engine knock, deactivating the direct injection fuel pump; and
activating the direct injection fuel pump from a deactivated state via engaging a low lift cam profile in response to fuel pressure less than a threshold in a fuel rail supplied fuel by the direct injection fuel pump while direct fuel injectors coupled to the fuel rail are deactivated in response to the absence of engine knock.

2. The method of claim 1 , further comprising operating the direct injection fuel pump with a third piston lift amount, the third piston lift amount greater than the second piston lift amount, the third piston lift amount activated during a third condition, the third condition different from the first and second conditions.

3. The method of claim 1 , where the direct injection fuel pump is deactivated via putting a zero lift cam profile in mechanical communication with the direct injection fuel pump over an engine cycle.

4. The method of claim 1 , further comprising transitioning between the first piston lift amount and the second piston lift amount via adjusting a position of a first lift cam and a second lift cam longitudinally along a direct injection fuel pump drive shaft.

5. The method of claim 4 , where the first lift cam and the second lift cam are adjusted via radially engaging an actuator pin into a displacing channel.

6. The method of claim 5 , where the displacing channel is formed in a cam sleeve.

7. A method of operating a direct injection fuel pump, comprising:
adjusting a cam profile sleeve lifting a fuel pump piston in response to an engine operating condition, the cam profile sleeve adjusted via shifting a position of the cam profile sleeve longitudinally along a direct injection fuel pump drive shaft, the cam profile sleeve adjusted between a position providing a zero lift cam lobe profile over an engine cycle and a low lift cam lobe profile, where the cam profile sleeve includes a first lift cam lobe profile and a second lift cam lobe profile, and where the engine operating condition is an indication of borderline engine knock, where the first lift cam lobe profile is the zero lift cam lobe profile and where the second lift cam lobe profile is the low lift cam lobe profile, and where a piston of the direct injection fuel pump is stationary over the engine cycle as the direct injection fuel pump drive shaft rotates, and where the zero lift cam lobe profile is activated to deactivate the direct injection fuel pump; and
transitioning from the zero lift cam lobe profile to the low lift cam lobe profile in response to direct injection fuel rail pressure in a fuel rail supplied fuel by the direct injection fuel pump when direct fuel injectors are deactivated.

8. The method of claim 7 , where the cam profile sleeve further comprises a third lift cam lobe profile, and where the third lift cam lobe profile is a high lift cam lobe profile.

9. The method of claim 7 , where the position of the cam profile sleeve is adjusted via engaging an actuator pin.

Assignees

• Ford Global Tech Llc

Inventors

• Glugla Chris Paul
• Doering Jeffrey Allen
• Jahr Ken

Classifications

• F04B9/042

  the means being cams · CPC title

• F02D1/10

  mechanical · CPC title

• F02D41/406

  Electrically controlling a diesel injection pump (F02D41/401 takes precedence) · CPC title

• F04B1/0413

  Cams · CPC title

• F02D41/3845 Primary

  by controlling the flow into the common rail, e.g. the amount of fuel pumped · CPC title