Fuel injection pump for internal combustion engines

US5291867A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Karsten Hummel · Freising, DE
• Karl Rapp · Stuttgart, DE
• Ernst Ritter · Stuttgart, DE

Key dates

• Filing date: May 14, 1993
• Grant date: Mar 8, 1994
• Expiry date: May 14, 2013

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F02M63/022
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A fuel injection pump for internal combustion engines having in-line cylinder bushes, in each of which a pump piston defining a pump work chamber is guided, the piston being rotatable by a governor rod for the sake of fuel supply quantity regulation. Mounted on the pump housing is an adjusting device, in which an adjusting piston is guided axially parallel with the governor rod; the adjusting piston has a radial pin, which protrudes through a slit in the wall of the adjusting device and pump housing into an oblong slot of the governor rod, thus limiting the adjusting motion of the rod in certain operating ranges. The position of the adjusting piston determines the maximum governing travel of the governor rod in the full-load direction upon engine starting. The adjusting piston is variable via an adjustable stop acting upon one face end thereof and is also variable as a function of temperature via a temperature-dependent spring element disposed on its circumference. In addition, with its face end, the adjusting piston defines a pressure chamber, by way of which the adjusting piston can be adjusted pneumatically in the direction of a zero supply quantity; via two stops of the oblong …