Fuel injection system for an internal combustion engine

US5255655A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Helmut Denz · Stuttgart, DE
• Andreas Roth · Karlsruhe, DE
• Ernst Wild · Oberriexingen, DE

Key dates

• Filing date: Jan 29, 1991
• Grant date: Oct 26, 1993
• Expiry date: Jan 29, 2011

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02B1/04
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

In a fuel injection system for an internal combustion engine, the system calculates the pulse width of the angle-synchronous fuel injection pulses from a main load sensor, such as an inlet manifold pressure sensor (22) or a hot film or hot wire air mass meter (24). Under rapidly-changing load conditions of the engine, the signal from the main load sensor is not sufficiently accurate to maintain a closely stoichiometric mixture. The present invention provides a throttle valve angle sensor for monitoring the degree of opening of an engine throttle (18), and changes the calculation of the basic angle-synchronous fuel injection signal when the measured rate of change of the throttle valve angle reaches a predetermined valve. The change of calculation may comprise altering filtering characteristics of a filter function normally applied to the basic angle-synchronous fuel injection signal, altering the sampling of the signal from the engine load sensor, or deriving the basic angle-synchronous fuel injection signal from the throttle valve angle signal instead of from the main load sensor signal. Furthermore, the load change compensation may be changed to a calculation from the throttle va…