Equipment for admitting fresh air to exhaust gas of IC engine to supply after burner has interlock system to prevent air valve opening when pump is not running

摘要

The air is supplied by a secondary air pump (3) through a valve (4) which opens when a partial vacuum is applied to its control feed (6). This is provided through a pneumatic valve (7) from a partial vacuum source (5) only if the pump is applying pressure to the control chamber (7d) of the pneumatic valve