David F Conway

US Patent:

50121251, Apr 30, 1991

Filed:

Jun 3, 1987

Appl. No.:

7/057956

Inventors:

David W. Conway - Cedar Rapids IA

Assignee:

Norand Corporation - Cedar Rapids IA

International Classification:

H01B 718

US Classification:

307149

Abstract:

A current carrying wire is provided with a tubular shield construction which essentially covers the wire with conductive material, and preferably emulates a classical Faraday shield. The shield is formed of a multiplicity of insulated shield wires for minimized eddy current loss. When such a shielded wire construction is formed into a primary winding of a power transformer for a switching power supply, the secondary circuit is protected from electric shock hazards while enabling use of a gap free toroidal core for close coupling between primary and secondary windings. In another embodiment, such shields are used on both the primary and secondary windings of a matching transformer and are arranged for common mode rejection of noise associated with low power data signals.

US Patent:

48902179, Dec 26, 1989

Filed:

Feb 17, 1989

Appl. No.:

7/312404

Inventors:

David W. Conway - Cedar Rapids IA

Assignee:

Norand Corporation - Cedar Rapids IA

International Classification:

H02M 704

US Classification:

363143

Abstract:

In a point of sale terminal it was desired to incorporate a variety of input/output devices, e. g. CRT display, disk drives and a printer in a compact hosuing, e. g. about 16 inches wide by 12 inches in depth (without frontally projecting keyboard) by about 11 inches high. The illustrated switching power supply occupies a rectilinear space of less than 155 cubic inches and has the capability of operating from either 110 or 220 VAC, 50 or 60 hertz, or from battery power, with essentially constant volt-second product, while supplying a maximum average output power greater than 120 watts, and a peak output power of greater than 280 watts.

US Patent:

59496339, Sep 7, 1999

Filed:

Oct 31, 1997

Appl. No.:

8/962157

Inventors:

David W. Conway - Cedar Rapids IA

Assignee:

Rockwell International Corporation - Costa Mesa CA

International Classification:

H02H 704

US Classification:

361 91

Abstract:

A transformer over-voltage protection circuit shuts down a resonant inverter when high voltages occur at the output of a transformer. The high voltages can be caused by a broken or removed display tube. The system is designed to be used in display system, such as, an active matrix liquid crystal display (AMLCD). The system senses the voltage at the output of the transformer by utilizing a tickler or a tertiary winding. The signal from the tertiary winding is rectified and compared to a threshold. If the signal from the tertiary winding is greater than the threshold, the inverter is shut down for a period of time.

US Patent:

58251332, Oct 20, 1998

Filed:

Sep 25, 1996

Appl. No.:

8/719935

Inventors:

David W. Conway - Cedar Rapids IA

Assignee:

Rockwell International - Costa Mesa CA

International Classification:

H05B 3702

US Classification:

315105

Abstract:

A fluorescent lamp drive circuit is disclosed. The fluorescent lamp drive circuit includes first filament drive circuitry coupled to the filaments of the lamp for driving the fluorescent lamp with a first waveform having sufficient amplitude such that gases in the fluorescent lamp are not allowed to extinguish during a prolonged period of operation. The fluorescent lamp drive circuit also includes second filament drive circuitry coupled to the filaments of the lamp for adjustably driving the fluorescent lamp with a second waveform during the prolonged period of operation. The second waveform has an amplitude which is adjustable over a wide range of voltages to achieve a wide range of fluorescent lamp luminance levels. Synchronization circuitry provides an input to the second filament drive circuitry to automatically facilitate the efficient transfer of power from the second filament drive circuitry to the fluorescent lamp over a wide range of lamp pressures and operating temperatures.

US Patent:

51500337, Sep 22, 1992

Filed:

Dec 9, 1988

Appl. No.:

7/282009

Inventors:

David W. Conway - Cedar Rapids IA

Assignee:

Norand Corporation - Cedar Rapids IA

International Classification:

H02J 704
H02H 504

US Classification:

320 51

Abstract:

A preferred protective current limiter comprises a positive temperature coefficient (PTC) resistor which automatically assumes a relatively high impedance state quickly enough to prevent venting of flat plate lead acid batteries under adverse charging conditions. For example, a fast charger with unlimited current and sixteen volt DC output (such as may be provided by a faulty vehicle electrical system) is found to cause venting without the limiter, while a PTC resistor selected according to the present disclosure safeguards the battery against venting while yet conducting a sufficiently high current to essentially equalize the charge condition of the battery cells within five minutes or less. Preferably a bypass resistor shunts the PTC resistor to avoid any problem which might arise if the PTC resistor became sufficiently heated to assume a current blocking state. At any given charging rate, the shunt resistor shares the total current, tending to moderate the heating of the PTC resistor, and leading to a more efficient charging of the battery after the initial cell equalization phase.

US Patent:

59090910, Jun 1, 1999

Filed:

Oct 31, 1997

Appl. No.:

8/962158

Inventors:

David W. Conway - Cedar Rapids IA

Assignee:

Rockwell International - Costa Mesa CA

International Classification:

H01J 1104

US Classification:

315358

Abstract:

An active matrix liquid crystal display (AMLCD) system is for use in avionic applications. The system includes an integral cathode fall indicator. The indicator relies on a gas fill mixture to provide an orange glow when the cathode fall region has an abnormally high potential across it. During normal operation, the gas fill mixture provides a light blue glow. The gas mixture includes helium, neon, argon, krypton, and xenon.