Abstract: A gauging apparatus for monitoring the height or level of liquid contained in a storage tank or the like. The apparatus comprises a probe device in the form of an elongate piece of insulating material carrying a first plurality of spaced-apart conducting members disposed along the length thereof, and a second plurality of conducting members disposed adjacent the members of the first plurality and forming multiple capacitors therewith, respectively. The insulating material, as well as the members carried thereby, are covered by a coating of insulating resin such that they are sealed against physical contact with the liquid being monitored. Detector means including amplifiers and indicators are provided for sensing which members of the first plurality are submerged in liquid at any particular time. The detector means responds to changes in the dielectric of the capacitors as they successively become submerged to provide indications of the liquid level in the tank.

Abstract: A machine tool dial assembly to enable readings indicative of the linear displacement of a machine element to be taken simultaneously in Metric and English units of measurement. The English dial is driven directly by the feed screw shaft and rotates in unison therewith. The Metric dial is mounted adjacent to and coaxially with the English dial and driven by means of the feed screw shaft through a gearing arrangement having an appropriate conversion ratio and comprising externally toothed driving and driven gears and a pinion gear in intermeshing engagement therewith. The dials are frictionally adjustable independently of the gearing arrangement and feed screw shaft by virtue of spring-biased friction shoes in contact with the inner surfaces of the dials.

Abstract: An audio-visual unit includes a disc mounting a plurality of discrete image transparencies arranged in a continuous pattern for successive visual display; a record co-axially mounted on the disc includes separate recorded messages corresponding to respective transparencies on the disc. The projector includes an advance mechanism manually operable successively for intermittently rotating the disc thereby to present the transparencies in seriatim for visual display. An indexing mechanism is operated in response to actuation of the advance mechanism for intermittently moving a tone arm to successive positions corresponding to the starting grooves of respective messages on the record.

Abstract: A method of and an apparatus for reproducing information recorded on a thin sheet with no central hole for placing the sheet in position, in which a plurality of switches are provided, at least one of which can be closed if there is a sheet present on a turntable and the other of which can be closed if a lid is completely lowered. A pickup arm is provided with a reproducer stylus and can be moved to the starting point when the lid is raised, so that actuating both switch means can cause the motor circuit to be closed for driving the turntable for rotation, and reproduction can be repeated by operating the lid.

Abstract: A film projection viewing system employs a projector to receive cartridges loaded into the projector in a manner completing a light path through the projector to a viewing screen. A film projector and cartridge having a substantially self-contained film transport therein cooperates to provide a system having a lens system with a focal length setable to a predetermined position in response to insertion of a cartridge into the projector.

Abstract: Apparatus for retrieving images of microfilms on sheet-like microforms on which the microfilms form frames arranged in vertical and horizontal rows and including larger and smaller frames. A transporting unit can move a microform up or down in a vertical plane so as to place a selected horizontal row of frames in front of a horizontal light source. A carriage in front of the transporting unit supports two lenses which are in line with the light source and respectively serve to project the images of larger and smaller frames onto the screen of a television camera. The carriage is movable horizontally to place a selected lens into register with a selected frame of that horizontal row of frames which is located in front of the light source, and the carriage can transmit motion to a plate- or belt-like diaphragm which is disposed between the transporting unit and the lenses and has one or more apertures registering with that lens which projects the image of a selected frame onto the screen.

Abstract: An optical device for concentrating in a plane a radiation modulated by an object, carrying data. It comprises a mask splitting an incident beam into a plurality of elementary beams, and two stigmatic systems, the first of which for focussing and the second for converging the elementary beams into a predetermined zone, which is the image of the source of the incident beam; the modulating object comprises elementary zones bearing said data, these zones being arranged in the path of the elementary beams.