Fuel injection apparatus for injecting a fuel mixture comprising at least two components

US4554903A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Max Straubel · Stuttgart, DE
• Klaus Zimmermann · Alzenau, DE

Key dates

• Filing date: Mar 2, 1984
• Grant date: Nov 26, 1985
• Expiry date: Mar 2, 2004

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M43/02
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

In the pump work chamber of a fuel injection pump, the main fuel delivered by a first metering valve is admixed with at least one further additional fluid by means of a second metering valve via a second inflow conduit. The two metering valves inserted into the inflow conduits and being electromechanically actuatable receive control pulses (I.sub.Z1, I.sub.Z2) dependent on operating characteristics (n, T, S, L) from an electric control unit. By means of the metering into the pump work chamber, the respective amounts of the fuel components are very well mixed or emulsified and pumped to the injection nozzle. The electric triggering of the metering valves enables a rapid adaptation from one stroke to another of the mixture ratio of the various fuel components to the instant operating condition of the internal combustion engine. A particularly advantageous feature is the use of a refill reservoir receiving the return-flow fuel quantity diverted at the end of supply and returning it to the pump work chamber before the next subsequent supply stroke begins, this refill chamber being connected to an overflow conduit controlled by an oblique control edge on the pump piston.