Illumination device having underground storage position
US4974134A · kind A · utility
Inventor
Key dates
| Filing date | Nov 29, 1989 |
| Grant date | Nov 27, 1990 |
| Priority date | — |
| Expiry date | Nov 29, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S362/802
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An illumination device that is stored below ground level when not in use and that extends above the ground when in use. A clear lens that protects a light bulb from the elements surmounts an inner housing member that is telescopically received within an outer housing member that is buried in the ground. When a motor is activated, the inner housing that carries the light bulb extends axially upwardly from the outer housing. When the inner housing reaches its fully extended position, a limit switch shuts off the motor. Subsequent reactivation of the motor retracts the inner housing and bulb back into the outer housing, and another limit switch shuts off the motor when full retraction has been achieved. A second embodiment has an improved structure that facilitates replacement of the motor, and a third embodiment has a further improved structure that eliminates several parts required in the first and second embodiments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.