Common rail injector in a high pressure common rail system are connected to the common rail through a short, high pressure tubing. Common rail injector and cylinder head are fixed in the same way as conventional injectors. Common rail injector mainly by the solenoid valve, pressure amplification system and hole needle valve parts and other components.
Pressure amplification system mainly consists of pressure control room, control piston and needle valve oil tank, needle valve and other components. The high-pressure fuel with the same pressure as the common rail flows into the injector through the inlet of the high-pressure oil and flows in two paths.
One path into the control valve into the top of the control piston pressure control chamber pressure on the top of the control piston, the pressure directly on the tail of the needle to control the needle valve lift.
Another path by the nozzle body into the oil into the hole into the oil tank, the role of the nozzle needle valve cone fuel pressure, the vertical component of the force equal to the rail pressure, but the control pin pressure surface (control pin top Surface) is greater than the vertical upward annular pressure bearing area on the conical surface of the nozzle needle valve. Therefore, the total pressure acting on the top surface of the control piston is greater than the vertical upward total pressure on the annular conical surface of the needle valve, Under the force can be a certain percentage of amplification.