A lamp electronic ballast with a piezoelectric cooling fan. Use of
ballast-driven lamps is limited in some lighting applications by thermal
considerations. For example, the problem of heat removal from compact
fluorescent lamps with integrated ballasts has limited their use.
Similarly, the use of ballast-driven fluorescent lighting in high hat and
other closed luminaire applications has been limited by thermal
considerations. Thermal management of ballasts for such thermally
sensitive applications is provided by a piezoelectric fan integrated with
the ballast. The power to drive the fan may be obtained from the same AC
line input that supplies the ballast, or from an AC ripple voltage present
at the output of a rectifier in the ballast, or from the output of the
ballast to the lamp, or from any suitable circuit location in the ballast.
The fan maybe a membrane-type spot-cooler comprising a thin membrane
carried by a frame mounted adjacent a hot spot. The membrane has one or
more holes in it and is vibrated about a central plane by suitably spaced
piezoelectric elements attached to the membrane.