Patent ID: 7137242
Filing Date: 2006-11-21
Classification: F02C,F23K,F23N,F23R,Y02T

Abstract:
1. A fuel control system for a staged combustion engine comprising, a fuel metering unit including a fuel metering valve having a fuel metering orifice the opening of which is varied to meter the flow of fuel through the metering valve in use, a fuel staging unit receiving fuel from the metering valve of the fuel metering unit and incorporating a staging valve for dividing the flow of fuel from the fuel metering unit to pilot burner and main burner output lines, a connection between a fuel pressure region of said fuel metering unit and a port of said staging valve, and, overthrust detection means causing said staging valve, in response to overthrust detection, to connect said port of said staging valve to low pressure, whereby to drain fuel under pressure from said pressure zone of said fuel metering unit to low pressure to limit or reduce the fuel supplied from the fuel metering unit to the fuel staging unit and thus to the engine in use.