US Patent 7476006 Automated lighting system with extendable and retractable light units

A lighting system includes multiple extendable and retractable light units. Each light unit includes a housing with inner and outer sleeves, which are telescopically interconnected. A drive assembly is located in each housing for extending and retracting the inner sleeve whereby a luminaire mounted in the inner sleeve can be selectively elevated. The housings are adapted for flush-mounting in the ground with their inner sleeves retracted. The lighting system can include a centralized control subsystem for collectively and individually operating the individual light units.