PURPOSE:To stably heat a filament for a discharge lamp by bringing the center of the winding width of an output winding of an output leakage transformer coincident to the center of the winding width of a filament winding and allowing the voltages produced at both the windings to become in phase. CONSTITUTION:In a leakage transformer 28, input windings 28a, 28b are wound through a bobbin 37 on a core 36, and a base winding 28c and filament windings 28e, 28f are wound partly thereon. The filament windings 28e, 28f are formed in the lowermost and uppermost layers of the output winding 28d in such a manner that the center of the width of the winding coincides approximately with the center of the output winding 28d. According to this construction, since the voltages of the windings 28e, 28f becomes in phase with the voltage of the winding 28d, the heating states of the filaments 28F1, 23F2 become stable, the formation of the filament spot after ignition is rapid, and the progress of blackening of the discharge lamp due to the energization and deenergization of the lamp can be largely improved.

Device for firing discharge lamp

An energy saving lighting control system for operating fluorescent light fixtures is provided with means for controlling the light level according to the light required for the task being done in the area. Ambient light available from sources outside of the controlled area such as daylight can be harvested to reduce the amount of artificial lighting required. A method of providing sensor inputs to detect occupancy in the controlled area provides control signals to the lighting control system which are used to reduce the light level or turn light fixtures off at times when the area is not occupied. A method of providing a central control of the operation of the lighting system can provide time-of-day scheduling, can provide minimum and maximum lighting levels, and can provide calibration and set-points for response times to various sensor inputs. In order to minimize the installation cost of the lighting control system, the system is provided with components that can be controlled using signals carried along the power conductors that provide primary operative power to the lighting fixtures. Special circuitry in the ballasts for fluorescent lamps provides a starting sequence and operating conditions that maximize the life of the lamps which therefore minimizes maintenance costs.

Energy management control system

A system for operating a fluorescent light is provided. The system comprises: a fluorescent lamp with at least one electrode having at least one corresponding heating filament; a filament signal power supply for providing a filament current signal having a filament current frequency, the filament signal power supply connected to create a filament current through the at least one filament; and a plasma signal power supply for providing a plasma power signal having a plasma power frequency, the plasma signal power supply connected to create a plasma current between the at least one electrode and a gas contained in the fluorescent lamp. The plasma power frequency is greater than the filament current frequency.

Methods and systems for dimmable fluorescent lighting using multiple frequencies

An energy saving lighting control system for operating fluorescent light fixtures is provided with means for controlling the light level according to the light required for the task being done in the area. Ambient light available from sources outside of the controlled area such as daylight can be harvested to reduce the amount of artificial lighting required. A method of providing sensor inputs to detect occupancy in the controlled area provides control signals to the lighting control system which are used to reduce the light level or turn light fixtures off at times when the area is not occupied. A method of providing a central .control of the operation of the lighting system can provide time-of-day scheduling, can provide minimum and maximum lighting levels, and can provide calibration and set-points for response times to various sensor inputs. In order to minimize the installation cost of the lighting control system, the system is provided with components that can be controlled using signals carried along the power conductors that provide primary operative power to the lighting fixtures. Special circuitry in the ballasts for fluorescent lamps provides a starting sequence and operating conditions that maximize the life of the lamps which therefore minimizes maintenance costs.

Energy management control system for fluorescent lighting

A semiconductor memory device comprises memory cells, a bitline connected to the memory cells, a read circuit including a precharge circuit, and a first transistor connected between the bitline and the read circuit, wherein a first voltage is applied to a gate of the first transistor when the precharge circuit precharges the bitline, and a second voltage which is different from the first voltage is applied to the gate of the first transistor when the read circuit senses a change in a voltage of the bitline.

Semiconductor memory device.

An apparatus for operating a gaseous discharge lamp comprises a DC power source, a transistor inverter which is connected to the DC power source through a switch, provided with at least one inverter transistor and generates an output having a prescribed frequency, and a discharge lamp which is energized by an output from the transistor inverter and having a pair of electrodes heated by part of the output The apparatus further comprises base current control means which holds the base current of the inverter transistor at a level lower than a first level during a prescribed length of time after the close of the switch, and holds the base current at the first level after the prescribed length of time The discharge lamp has its electrodes preheated, but does not display discharge when the base current has a level lower than the first level, and commences discharge when the base current reaches the first level and thereafter continues discharge

Apparatus for operating a gaseous discharge lamp

Base current is supplied from a base driving circuit (27) to bases of paired inverter transistors (14, 15) through a transistor (36), and an inverter circuit (11) oscillates at a rated output. When the operation of an electric discharge lamp (20) becomes abnormal, an IC-ed control circuit (49) is rendered operative responsive to output of an abnormality detecting circuit (51) to turn the transistor (36) ON and a transistor (48) OFF, and the operation of inverter circuit (11) is thus stopped. A capacitor (33) in an auxiliary power source (38) is charged by output of the base driving circuit (27) and the control circuit (49) is driven responsive to output of auxiliary power source (38) when the inverter circuit (11) is left inoperative.

Transistor inverter device

Device for dimming discharge lamp

Several Ways for Stabilizing HID Lamps Operation on High Frequency Power

A low frequency AC voltage is rectified through a full-wave rectifier to obtain a pulsating voltage, which is superimposed with an auxiliary voltage of a predetermined level provided from an auxiliary power source, and the resultant composite pulsating voltage is inverted at an inverter to a high frequency voltage. The high frequency voltage thus obtained from the inverter is used to operate a discharge lamp. Minimum value V min of the resultant voltage is set to be 1/3 to 4/5 of the maximum value V max of the resultant voltage.

Hisao Kobayashi

Papers

Apparatus for operating a gaseous discharge lamp

Transistor inverter device

Device for dimming discharge lamp

Several Ways for Stabilizing HID Lamps Operation on High Frequency Power

Apparatus for operating discharge lamps