Fuel supply system for relieving fuel pressure pulsations and designing method thereof

A fuel supply system for an internal combustion engine having a plurality of cylinders which are divided into a pair of banks, comprising:

• a fuel pump for pressurizing fuel;
• a plurality of injectors for directly injecting said pressurized fuel to said cylinders respectively;
• a high pressure fuel pipe for introducing said pressurized fuel to the injectors;
• a pair of delivery pipes, formed as a part of said high pressure fuel pipe, corresponding to the pair of banks for distributing said pressurized fuel to said injectors;
• and
• a connecting pipe, formed as a part of said high pressure fuel pipe, for connecting said pair of delivery pipes, wherein:
• said connecting pipe includes an enlarged volume portion whose inner diameter is greater than an inner diameter of said connecting pipe, and
• said enlarged volume portion is located at a position other than connecting portions of said pair of delivery pipes and said connecting pipe.

A fuel supply system for an internal combustion engine having a plurality of cylinders which are divided into a pair of banks, comprising:

• a fuel pump for pressurizing fuel;
• a plurality of injectors for directly injecting said pressurized fuel to said cylinders respectively;
• a high pressure fuel pipe for introducing said pressurized fuel to the injectors;
• a pair of delivery pipes, formed as a part of said high pressure fuel pipe, corresponding to the pair of banks for distributing said pressurized fuel to said injectors;
• and
• a connecting pipe, formed as a part of said high pressure fuel pipe, for connecting said pair of delivery pipes,
• wherein at least a part of said connecting pipe is provided by a flexible pipe alone, the pipe being made of flexible material.

A fuel supply system for an internal combustion engine having a plurality of cylinders, comprising:

• a fuel pump for pressurizing fuel;
• a plurality of injectors for directly injecting said pressurized fuel to said cylinders respectively;
• a high pressure fuel pipe for introducing said pressurized fuel to the injectors;
• a pair of delivery pipes, formed as a part of said high pressure fuel pipe, for dividing said injectors into a pair of injector groups and for distributing said pressurized fuel to each of the pair of injector groups;
• and
• a connecting pipe, formed as a part of said high pressure fuel pipe, for connecting the pair of delivery pipes to each other, wherein:
• said connecting pipe has a diameter larger than a diameter of said delivery pipe, and
• said connecting pipe is unified with said delivery pipes.

A fuel supply system for an internal combustion engine having a plurality of cylinders which are divided into a pair of banks, comprising:

• a fuel pump for pressurizing fuel;
• a plurality of injectors for directly injecting said pressurized fuel to said cylinders respectively;
• a high pressure fuel pipe for introducing said pressurized fuel to the injectors;
• a pair of delivery pipes, formed as a part of said high pressure fuel pipe, corresponding to the pair of banks for distributing said pressurized fuel to said injectors;
• and
• a connecting pipe, formed as a part of said high pressure fuel pipe, for connecting said pair of delivery pipes to each other, wherein:
• said connecting pipe has a diameter larger than respective diameters of said delivery pipes, and
• said connecting pipe is unified with said delivery pipes.

A fuel supply system for an internal combustion engine having a plurality of cylinders, comprising:

• a fuel pump for pressurizing fuel;
• a plurality of injectors for directly injecting said pressurized fuel to said cylinders respectively;
• a plurality of delivery pipes, formed as part of said high pressure fuel pipe, for distributing said pressurized fuel to said injectors;
• and
• a connecting pipe, formed as a part of said high pressure fuel pipe, to be connected to said delivery pipes, wherein:
• at least one pair of said delivery pipes adjacent each other are connected to via a flexible member on their substantially entire surfaces opposing each other,
• said connecting pipe connects the pair of said delivery pipes to each other,
• said connecting pipe has a diameter larger than respective diameters of said delivery pipes, and
• said connecting pipe is unified with said delivery pipes.

A fuel supply system for an internal combustion engine having a plurality of cylinders which are divided into a pair of banks, the system comprising:

• a fuel pump for pressurizing fuel;
• a plurality of injectors for directly injecting the pressurized fuel to the cylinders respectively;
• and
• a high pressure fuel pipe for introducing the pressurized fuel to the injectors,
• wherein the high pressure fuel pipe comprises a first delivery pipe for distributing the pressurized fuel to a first group of the injectors corresponding to the first bank of the engine;
• a second delivery pipe for distributing the pressurized fuel to a second group of the injectors corresponding to the second bank of the engine;
• and
• a connecting pipe which alone connects the first and second delivery pipes and through which the pressurized fuel passes from the first delivery pipe to the second delivery pipe, and at least a pipe-shaped part of the connecting pipe being made of flexible material.