Patent attributes
A gas-free light bulb device has a lamp head, heatsink, a bulb, a glass core column, multiple filament assemblies, and a resilient extending element. The heatsink is mounted on the lamp head and has a mounting slot and a driver circuit board mounted in the mounting slot. The bulb is mounted on the heatsink and has a cavity. The glass core column is mounted in the mounting slot. The filament assemblies are mounted on the glass core column. The resilient extending element is mounted on the glass core and has a resilient rubber sleeve mounted around the glass core column and multiple resilient extending rubber bars connected respectively to the filament assemblies. When the gas-free light bulb device is operated with rising temperature, the resilient rubber sleeve is heated and loosened to slide upward and drive the filament assemblies to contact the bulb to effectively dissipate heat.