VAPOR LEAK DETECTION SYSTEM HAVING A SHARED ELECTROMAGNET COIL FOR OPERATING BOTH PUMP AND VENT VALVE

摘要

An on-board evaporative emission leak detection system has a module for detecting leakage from an evaporative emission space of a fuel system of an automotive vehicle. Interior space of the module's enclosure is communicated to atmosphere. A pump is disposed within space and has an inlet communicated to the interior space and a flow passage at its outlet to allow the pump to create pressure in the evaporative emission space suitable for performance of a leak test. A vent valve is disposed within space and is selectively operable to vent and not vent the flow passage to space. An electromagnet actuator has a single electric coil that operates both the pump and the vent valve by cantilever-mounted armatures responsive to electric control current in the coil having a first current component for controlling the pump and a second current component for controlling the vent valve.