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Derr, L. J.

Publications and source records attributed to Derr, L. J..

Group-delay standards

Delay-line standards have been tested by three independent laboratories using six different methods. Results are published in report showing delay values obtained from 15-, 30-, and 60-ns cables by different laboratories. Study of potential error sources indicates that reflection errors due to discontinuities at ends of cables are usually small.

Beatty, R. W.

Ultrasonic scanner for footprint identification

Scanner includes transducer, acoustical drive, acoustical receiver, X and Y position indicators, and cathode-ray tube. Transducer sends ultrasonic pulses into shoe sole or shoeprint. Reflected signals are picked up by acoustic receiver and fed to cathode-ray tube. Resulting display intensity is directly proportional to reflected signal magnitude.

Derr, L. J.

Electrostatically controlled heat shutter

Electrically controlled chamber filled with inert gas efficiently removes heat from heat-generating components. System can be reversed to bring heat from external source to component.

Derr, L. J.

Electrostatically controlled heat shutter

A heat transfer assembly for conducting thermal energy is described. The assembly includes a hermetically sealed container enclosing a quantity of inert gas such as nitrogen. Two opposed walls of the container have high thermal conducting characteristics while the connecting walls have low thermal conducting characteristics. Electrodes are positioned adjacent to the high thermal conducing walls and biased relative to the conducting walls to a corona potential for creating an ionic gas wind which must contact the conducting walls to be neutralized. The contact of the gas molecules permits the maximum thermal energy transfer between the walls. Baffles can be positioned adjacent to the electrodes to regulate gas flow between the high thermal conducting surfaces.

Derr, L. J.

Heated bimetal strip prevents damage of bearings by vibration

Strip of bimetal is shaped as split ring; when properly fabricated from thin sheet, width of strip increases when it is heated. When width of strip increases, outer races are forced apart, thus pressing balls tightly against inner races. Strip applies axial load to bearing, amount of load being function of temperature to which strip is heated.

Derr, L. J.

Electrothermal linear actuator

Converting electric power into powerful linear thrust without generation of magnetic fields is accomplished with an electrothermal linear actuator. When treated by an energized filament, a stack of bimetallic washers expands and drives the end of the shaft upward.

Derr, L. J.