Valmont Industries, Inc.

General Electric Company

Dail L Swanson

Larry J Costa

Edward E Hammer

Eugene Lemmers

Charles A Burton

Raymond M Green

Gregory S Bennorth

Shannon Edwards

A wall box dimmer has a face plate having a pair of integral stand-offs extending rearwardly therefrom upon which is mounted a mounting strap. A circuit board is mounted on the rearward ends of the stand-offs. A back box is selectively removably secured to the mounting strap and covers the circuit board and circuit components.

Wall box dimmer

A circuit for starting and operating fluorescent lamps from an a-c low frequency power source includes a reactive ballast means connected to ballast the lamps and having a non-linear characteristic for producing a plurality of harmonics of the power source frequency, and a capacitor and a cathode heating transformer connected in series and connected to receive power from said ballast means and resonant in a frequency range encompassing a plurality of said harmonics. This resonant voltage is applied across the lamps to aid the starting of their discharge and thereafter the lamps operate at the a-c power source frequency. The aforesaid resonance frequency range preferably is broad enough to encompass several harmonics of the power source frequency, for example the third through the ninth harmonics (180 to 540 Hz for a source frequency of 80 Hz). Preferably a switch is connected in series with the capacitor and cathode heating transformer for opening the cathode heating circuit when the lamps are operating. This switch may be a bidirectional diode or equivalent voltage sensitive solid state switch, which switches on and off during each half cycle of the lamp starting time period and thus contributes to the harmonic content of the starting voltage waveform.

Circuit for starting and operating fluorescent lamps

A fluorescent lamp ballast includes a generally flat base upon which a core and coil subassembly is mounted and covered by a ballast case. A connector bar is mounted in the forward end of the ballast case and includes a plurality of sockets having terminal pins mounted therein for selectively receiving a wiring harness. The opposing ends of the terminal pins are electrically connected to a terminal strip which is mounted to the core and coil subassembly. The terminal strips have conductors electrically connected thereto which extend to termination points on the core and coil subassembly. A second series of terminal strips is mounted to the opposite end of the core and coil subassembly, and is electrically connected to a resistor and capacitor combination. A second embodiment of the ballast augments the first embodiment with an end connector bar mounted in the rearward end of the ballast case. A second version of a terminal strip, in the second connector bar, is designed to electrically connect terminal pins to either a conductor from the appropriate coil or to 'passed through' connections from terminals at the forward end. A third version of the ballast utilizes the second embodiment of the terminal strip at the forward end of the ballast case to permit rearrangement of the resistor and capacitor combination to the forward end.

Fluorescent lamp ballast with end connector

In one form of the multiple voltage ballast system described herein, each of the primary coils has different wire sizes with the largest diameter wire being utilized in the 120 V primary coil. In another form of the invention, a pair of 120 V primary coils are connected in series with a 37 V primary coil so that the ballast may function as a 277 V ballast. The primary coils are also electrically connected so that the ballast may be used as a 120 V ballast.

Dual voltage ballast

An improved ballast for a fluorescent lamp comprising a base having a core mounted thereon with a plurality of coils operatively electrically associated with the core with each of the coils having at least one conductor extending therefrom. An electrical connector is positioned adjacent the coils and has a plurality of connectors associated therewith which are electrically connected to predetermined conductors. A component subassembly is electrically connected to predetermined connectors. A case is positioned over the core, coils, connectors and the component subassembly. The case is provided with an access opening formed therein for providing access to at least a portion of the connectors so at least a portion of a wiring harness may be inserted therethrough for selective connection to predetermined connectors.

Ballast

A low pressure gas discharge lamp ballast circuit is provided for three series-connected low energy gas discharge lamps, in which a first starting capacitor provides a starting voltage to one of the lamps, and a second starting capacitor provides a starting voltage to a second one of the lamps in sequence, so that the ballast losses can be minimized by reducing the ratio of the voltage applied across the three lamp system to the total lamp voltage, while still maintaining the light output and not having to use expensive lamp bases and lampholders.

Three lamp ballast

A circuit for starting and operating fluorescent lamps from an a-c power source, comprising reactive ballast means connected to ballast the lamps and having a non-linear characteristic for producing harmonics of the power source frequency, and a capacitor and a cathode heating transformer connected in series and connected to receive power from said ballast means and resonant in a frequency range including two or more of said harmonics. A switch may be connected in series with the capacitor and cathode heating transformer for opening the cathode heating circuit when the lamps are operating, to conserve electrical energy.

Growing community of inventors

Danville, IL, United States of America

Dail L Swanson