Abstract: An optical transducer having concentric radiant beam detectors for converting a radiant beam to electrical signals including a first axially placed detector with a second detector concentric therewith. In one embodiment, the detectors receive the radiant beam through an amplifying auxiliary lens. Changes in focus differentially affect the magnitude of the beam impinging on the individual detectors, resulting in corresponding changes in the individual detector outputs.A focusing system employing the transducer moves a focusing lens in response to the differential output of the individual detectors. The focusing system can be employed in a video disc reading system so that the video disc scanning beam is always focused precisely at the disc. An electrical difference circuit leading from the photo-detectors generates a driving signal to energize a lens-moving motor for shifting the focusing lens along the axis of the beam.

Abstract: A video disc master of glass, having a metal surface with microscopic apertures therein representing information, is coated with a photosensitive resist. The resist is uniformly exposed through the glass disc. The unexposed resist is removed. The resulting disc having surface irregularities can be used in a first process to produce "stampers" for embossing replicas and, in a second process, to produce a mold for casting replicas.

Abstract: A matrix is used to prepare a mold of an elastomeric material. A polymerizable compound is coated onto a flexible, thin substrate such as Mylar and is placed with compound side in intimate contact with the mold. The compound is cured and is bonded to the substrate. The cured combination is stripped from the mold and is given a metallic coating to improve reflectivity. A clear plastic coating may be applied to protect the metal surface.

Abstract: A matrix is used to prepare a mold of an elastomeric material. A polymerizable compound is coated onto a flexible, thin substrate such as Mylar and is placed with compound side in intimate contact with the mold. The compound is cured and is bonded to the substrate. The cured combination is stripped from the mold and is given a metallic coating to improve reflectivity. A clear plastic coating may be applied to protect the metal surface.

Abstract: A videodisc system utilizes a beam of light which tracks the center of an interrupted spiral information channel. The light beam is "dithered" from side to side of the channel in order to determine the relative "direction" of a beam deviating from the center of the channel. The beam oscillates by approximately one-third of the width of the channel. By multiplying the returned signal by the drive signal, a signal is derived whose mean value is positive on one side of the track, negative on the other side and zero when in the center of the track.

Abstract: In the art of recording video signals, apparatus for drop-out compensation by detecting "missing" positive or negative going half cycles of recorded carrier signals includes logic for generating a "new" half cycle of appropriate polarity to replace individual missing half cycles which is inserted into the original recorded signal train. If a plurality of consecutive half cycles are missing, memory circuits supply signal information that approximates the information contained in the missing half cycles.

Abstract: A process and product is hereinafter described for fitting a brake shoe to a brake drum. The process comprises the steps of removing an existing brake shoe from a brake assembly; establishing the relationship of the arc of the curve of the removed brake shoe to its anchor pin; and fitting a new brake shoe to the established relationship between the arc of the drum and its respective anchor pin. An adjustable mechanism is shown whereby the relationship of the arc of the shoe to the anchor point can be established by movable mechanisms.

Abstract: An apparatus is described for treating air for use as a coolant for machinery. The treatment includes cooling the air with water without injecting water droplets into the air stream which droplets can visibly be seen to come to rest on the machinery. The principal elements of this water treatment apparatus comprises: low water resistance evaporation means for cooling air passing therethrough; and water dispensing means for uniformly adding water to the water evaporaton means by having water exude from the water dispensing means over an area of mutual contact with the water evaporation means. Improved embodiments employ a temperature sensing mechanism for activating the air treating mechanism dependent upon the temperature of the ambient air. A further embodiment includes a water pressure regulator means for maintaining the required effluence from the water dispensing means to obtain the optimum wetting of the evaporation means.

Abstract: An improved mass production assembly line is provided for fabricating building walls and similar structural members in molds by applying a hardenable polyester film to the cavity surfaces of mold halves, joining the mold halves and then introducing a mixture into the mold cavity to form a polyurethane foam.First and second rectangular fields of rollers, each mounted on a pedestal, are adapted to carry respective mating halves of each mold in a horizontal plane from a start end of the fields to the terminating end. The mold cavities face upwardly. The lower surface of each mold half has secured thereto elongated T-shaped bars. The bars are parallel with each other, and each bar is adapted to be carried by one line of rollers in a respective one of the fields. The parallel axes of the rollers are set to an exact height by means of a laser light source and photoresponsive means so that the upper edges of the rollers lie in the same horizontal plane.

Abstract: An in-line filter unit is provided for use in a circulating fluid system. Such a unit is made essentially into one piece to insure watertight. A debris reservoir is provided to store the debris removed from the fluid. A diffuser is placed in the line of fluid flow for preventing direct contact by the fluid entering the unit with the filter and for preventing damage to the filter.

Abstract: A clamping assembly is disclosed to hold walls and the like in position during construction of housing. The assembly is located and supported by a base which is held in place by nails driven into the floor. An upright beam held by the base is keyed at a location above the walls being held together to a rod connected to a vise unit. The vise is manually closed around one of the walls being joined. Movable jaws spaced along the upright beam are manually moved into contact with the other wall. The assembly is economic, effecient, and adapted for reuse.