An electrostatic printer employing a source of coherent electromagnetic radiation in conjunction with electro-optical equipment for spatially modulating and focusing the radiation to a printing medium disposed between a first electrode transparent to the radiation and a second electrode. A focal point of radiation is established adjacent the printing medium, and the energy present there interacts with gas molecules to create ions, which are attracted to the medium by an electric field establishe...

An instrument face constructed and lighted from behind so that only the information displayed thereby is illuminated, and incorporating a visual warning signal visable only over a selected value range of the displayed information. A rotating opaque disc incorporating a translucent pointer is arrayed behind a surrounding opaque ring bearing a translucent scale; such that light from behind may escape only through the scale and pointer. A red translucent area on the disc cooperates with an opening ...

A conversion unit for attachment to a machine tool constructed to operate normally in English units of measurement so that the machine tool may be used directly in metric units, or vice versa. The unit comprises an externally toothed gear wheel which may be fitted to a screw of the machine tool to turn with it, and an internally annular gear eccentrically mounted to mesh with the other gear, the number of teeth on the gears being chosen so that the correct conversion ratio is produced, the measu...

Apparatus for measuring angular displacement of an object in which an alternating potential source is applied to the electrodes of a light source, such as a gaseous discharge light, resulting in alternating illuminations in the medium, e.g., gas, about the respective electrodes, which are detected by photodetector means. The light source and the photodetector means are mounted such that the distances between the photodetector and the respective electrodes vary proportionately with any rotation o...

An auxiliary instrument having an open ended back casing is removably mounted on an automobile dashboard in a visible position by a friction spring clip assembly affixed to the dashboard surface by an adhesive layer. The friction spring clip slips back over the back edge of the casing and extends into the open back end to avoid any protruding structure on the casing, which is thereby removably held in place by the simple expedient of frictionally forcing backward into the spring clip.

Arch spring loading is provided for the stylus of a recorder utilizing pressure-sensitive chart paper carried through a fixed gap between a backing plate and a transparent front plate with means for moving the stylus transversely to the direction of motion of the chart paper in accordance with variations in magnitude of a quantity to be recorded. A steel band movable in accordance with variations in the quantity to be recorded is provided for carrying the stylus. The arch spring is in the form o...

The invention relates to a tracing apparatus operating automatically on the basis of digital imputs. A buffer-loop is formed in the paper band between each drive roll and the control drum, and the loops so formed are balanced by a loop corrector/reader device. In one prior art apparatus, this device includes photoelectric cells. The tracing apparatus is characterized in that it includes three suction chambers, one for each buffer-loop and a third central chamber beneath the control drum, whereby...

Fiber optic displacement/position measuring apparatus having increased working distance and measuring range capability is provided by combining an optical extending sensing head in fixed relationship with the common end of a bifurcated fiber optic bundle. The sensing head includes a lens system which is operative to focus the image of the end face of the fiber optic bundle onto the surface of an object whose displacement is to be determined and to refocus that image back onto the end in an uprig...

A variable capacitive transducer is employed in a graphical recording device in conjunction with its pen drive mechanism. Two fixed conductive plates are mounted within the recorder parallel to each other and a flexible belt, partly coated with a conductive film, is movably mounted therebetween. The recording pen is attached to the belt which serves as both the feedback element in the pen drive servo system and pen conveyor. Since the pen is attached directly to the belt which, in turn, provides...

A round or strip chart recorder preferably of the self-balancing type for recording and indicating the values of a plurality of measured quantities. This recorder is characterized by a plurality of stacked recording modules each comprised of a pivoted frame including a pair of side plates or arms secured in parallel spaced relation by support shafts which also serve as guide rods for a marker carriage assembly. The frame supports a scale, motor and drive means for the marker carriage, and a mark...