Vane Pump Recesses Reduce Stiction for Evaporative Leak Detection

The patent applies local quality by introducing recesses only at specific locations on the vane surfaces where they contact the rotor, rather than modifying the entire surface. This localized modification reduces stiction at critical contact points while maintaining smooth surfaces elsewhere for ease of manufacture. The recesses create micro-gaps that prevent vapor condensation and reduce adhesion forces exactly where needed.

The patent segments the vane surface into multiple recesses distributed across the contact areas, rather than creating one large complex feature. Each recess is a simple geometric element that can be independently formed, reducing overall manufacturing complexity while collectively providing the stiction reduction benefit across the entire vane-rotor interface.

The patent implements self-service by designing the recesses to automatically reduce stiction through passive physical mechanisms during normal pump operation. The recesses create micro-gaps that naturally prevent vapor condensation and reduce adhesion forces without requiring external control systems, sensors, or active components, thereby achieving faster and more reliable leak detection without increasing system complexity.