Fuel injection pump for diesel internal combustion engines

US5209208A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Hans-Joachim Siebert · Schwieberdingen, DE
• Hermann Grieshaber · Ingolstadt, DE
• Bernhard Schenk · Eppelheim, DE
• Walter Egler · Stuttgart, DE
• Norbert Meissner · Neustadt, DE

Key dates

• Filing date: Feb 18, 1992
• Grant date: May 11, 1993
• Expiry date: Feb 18, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02T10/12
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A fuel injection pump designed to deliver an amount of fuel divided into a pilot and a main injection volume, including a surface of a pump plunger which is guided within a pump cylinder, apart from two recesses limited by an inclined control edge, a first horizontal control edge is formed by a frontal shoulder; and on a side opposite the shoulder, it has a fully enclosed transverse groove with a second and third control edge. Two control apertures and an annular groove above them in the wall of the pump cylinder effect the control, in conjunction with the aforementioned control edges, of the precisely determinable pilot injection and, after a delivery interval, determined by the difference (b-a) between the width (b) of the transverse groove and the distance of the annular groove to the control aperture, the subsequent main injection. For the purpose of controlling an exact and largely speed-independent start of delivery of both the pilot and the main injection, the control apertures can be equipped with a straight limiting edge on the pump chamber side.