Apparatus for operating a fluorescent lamp of an image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorsToshiyuki Sekiya, Tadashi Ishikawa, Atsushi Asayama
Life of this patent
Estimating the term…
Abstract
An apparatus for operating a fluorescent lamp having first and second power source circuits, the second power source circuit including a high frequency transformer having two or more outputs for supplying pre-heating electric currents to filaments, the second power source circuit being arranged to be controllable individually from the first power source circuit for supplying a tube electric current to turn on a fluorescent lamp so that the electric power level for pre-heating the filaments is switched between a state where a light adjustment is performed by turning on/off a tube electric current at high frequency and a state where the fluorescent lamp is turned off in a standby mode.
Claims32
An apparatus for operating a fluorescent lamp comprising:
- first power source means for supplying a tube electric current to the fluorescent lamp to turn on the fluorescent lamp;
- second power source means for supplying pre-heating electric currents to filaments of the fluorescent lamp;
- and
- switching means for switching an electric power level of the pre-heating electric currents to be supplied to the filaments by said second power source means by changing a ratio of supply/non-supply of the pre-heating electric currents to the filaments.
An apparatus for operating a fluorescent lamp comprising:
- first power source means for supplying a tube electric current to the fluorescent lamp to turn on the fluorescent lamp;
- second power source means for supplying pre-heating electric currents to filaments of the fluorescent lamp;
- and
- control means for monitoring an output from said second power source means to control the electric power level of said pre-heating electric currents to be supplied from said second power source means to the filaments by changing a ratio of supply/non-supply of the pre-heating electric currents to the filaments.
A method of operating a fluorescent lamp comprising the steps of:
- supplying a tube electric current to a fluorescent lamp to turn on the fluorescent lamp;
- supplying pre-heating electric currents to filaments of the fluorescent lamp;
- and
- switching an electric power level of the pre-heating electric currents to be supplied to the filaments by changing a ratio of supply/non-supply of the pre-heating electric currents to the filaments.
A method of operating a fluorescent lamp comprising the steps of:
- supplying a tube electric current to a fluorescent lamp to turn on the fluorescent lamp;
- supplying pre-heating electric currents to filaments of the fluorescent lamp using a second power source means;
- and
- monitoring an output from the second power source means to control the electric power level of the pre-heating electric currents to be supplied to the filaments by changing a ratio of supply/non-supply of the pre-heating electric currents to the filaments.
An apparatus for operating a fluorescent lamp comprising:
- first power source means for supplying a tube electric current to the fluorescent lamp to turn on the fluorescent lamp;
- second power source means for supplying pre-heating electric currents to filaments of the fluorescent lamp;
- and
- switching means for switching an electric power level of the pre-heating electric currents to be supplied to the filaments by said second power source means by changing an amplitude of the pre-heating electric currents to be supplied to the filaments.
An apparatus for operating a fluorescent lamp comprising:
- first power source means for supplying a tube electric current to the fluorescent lamp to turn on the fluorescent lamp;
- second power source means for supplying pre-heating electric currents to filaments of the fluorescent lamp;
- and
- control means for monitoring an output from said second power source means to control the electric power level of said pre-heating electric currents to be supplied from said second power source means to the filaments by changing an amplitude of the pre-heating electric currents to be supplied to the filaments.
A method of operating a fluorescent lamp comprising the steps of:
- supplying a tube electric current to a fluorescent lamp to turn on the fluorescent lamp;
- supplying pre-heating electric currents to filaments of the fluorescent lamp;
- and
- switching an electric power level of the pre-heating electric currents to be supplied to the filaments by changing an amplitude of the pre-heating electric currents to be supplied to the filaments.
A method of operating a fluorescent lamp comprising the steps of:
- supplying a tube electric current to a fluorescent lamp to turn on the fluorescent lamp;
- supplying pre-heating electric currents to filaments of the fluorescent lamp using a second power source means;
- and
- monitoring an output from the second power source means to control the electric power level of the pre-heating electric currents to be supplied to the filaments by changing an amplitude of the pre-heating electric currents to be supplied to the filaments.
Dependencies are inferred from the claim text.