Fuel injection system

A fuel injection system for mixture compressing, externally ignited internal combustion engines, including:

• a. a plurality of fuel injection valves equal in number to the number of engine cylinders;
• b. a fuel distributing unit having a plurality of fuel metering valves equal in number to the plurality of fuel injection valves;
• c. a plurality of pressure valves equal in number to the plurality of fuel injection valves;
• d. means connecting each of said pressure valves to a respective one of said fuel injection valves;
• and
• e. further means connecting each of said pressure valves to a respective one of said fuel metering valves, wherein:
• i. each of said pressure valves includes means producing a defined space, and a flexible member which divides the defined space into first and second chambers;
• ii. the flow cross section of each of said pressure valves can be changed by its flexible member;
• iii. the pressure in the first chamber of each pressure valve is the fuel pressure prevailing downstream of its respective fuel metering valve, said prevailing pressure acting on the flexible member in an opening direction of the pressure valve;
• iv. said connecting means and said further connecting means for each pressure valve define with their respective pressure valve a fuel flow path from the fuel metering valve to the fuel injection valve associated with the respective pressure valve;
• v. the fuel metering valves determine the fuel quantity flow through the various flow paths by jointly changing their flow cross section;
• vi. at least one of said pressure valves is embodied as an equal pressure valve and at least one of said pressure valves is embodied as a differential pressure control valve;
• vii. the pressure in the second chamber of the differential pressure control valve is the pressure prevailing upstream of the fuel metering valves;
• viii. means are provided so that the first chamber of the differential pressure control valve communicates with the second chamber of each of said equal pressure valves;
• and
• ix. fuel metering occurs at a constant pressure difference due to (i) - (viii).