Method and arrangement for controlling the operation of a secondary air pump

US5319928A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Rainer Bone · Leinfelden, DE
• Jog Lange · Lambach, DE
• Winfried Moser · Ludwigsburg, DE

Key dates

• Filing date: Dec 18, 1992
• Grant date: Jun 14, 1994
• Expiry date: Dec 18, 2012

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F01N3/20
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

The emission of toxic materials when starting an internal combustion engine equipped with a catalytic converter and a secondary air pump can be further reduced with the method and arrangement of the invention. This reduction takes place by a switch-on of the secondary air pump under selectable conditions which include a warm start of the engine. The danger of overheating the catalytic converter by the operation of the secondary air pump for a warm engine is taken into account by a variable switch-on duration of the secondary air pump which can be realized by a counting procedure having an increment dependent on operating parameters.