Pneumatic diaphragm control element for a fuel injection apparatus in internal combustion engines

US4727839A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Werner Bruhmann · Stuttgart, DE
• Werner Lehmann · Leinfelden, DE
• Matthias Schmidt · Munich, DE

Key dates

• Filing date: Mar 10, 1986
• Grant date: Mar 1, 1988
• Expiry date: Mar 10, 2006

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02B3/06
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A pneumatic diaphragm control element for a fuel injection apparatus for internal combustion engines, in particular for supercharged diesel engines, has a thrust rod that is axially displaceable between two end stop counter to the force of a restoring spring, which thrust rod acts upon a control member of the fuel injection apparatus and is connected to a pressure-actuated diaphragm. One end stop determines the position assumed by the thrust rod when there is no pressure and is embodied as a stop screw for the thrust rod. The second end stop defines the position assumed by the thrust rod with maximal pressure being exerted on the diaphragm, and to this end cooperates with a counterpart stop that is adjustably coupled with the thrust rod. For better adaptation of the regulating characteristic, the counterpart stop is embodied as a pre-stressed spring assembly with two stop positions, such that when the first stop position is attained, after the spring pre-stressing is overcome, a further displacement travel (S.sub.2) of the thrust rod until the second stop position is attained is available.