AIR-FUEL RATIO CONTROL METHOD AT STARTING OF GAS ENGINE

摘要

PROBLEM TO BE SOLVED: To maintain starting performance and operating performance of an engine efficiently from cold state non-load starting to warm state non-load operation in a multi-cylinder gas engine. SOLUTION: This method is applied to a multi-cylinder gas engine of a multi-point injection method that has a first route to supply fuel gas directly to a sub-chamber 13 by a valve 15 and a second route to inject fuel gas to a scavenging branch pipe 2 by an injector 30 and to supply to a main combustion chamber 12 through a scavenging port 1. The check valve 15 introduces scavenging pressure at the lower flow side from a throttle valve 5 to a regulator 20 for adjustment of sub-chamber gas pressure to control the sub-chamber supply gas pressure in accordance with the increase/decrease of the scavenging pressure. When an engine is started, it fixes the throttle valve 5 to a prescribed opening at starting linked with a main switch device 45 so that an air-fuel ratio to start the engine can be obtained.