Abstract: The display comprises a cholesteric liquid crystal film in which are embedded dye molecules between the two walls separated by a shim. One wall is at least partly covered by a reflecting coating reversing the polarization of a circularly polarized electromagnetic wave. The optical anisotropy .DELTA.n and the helix pitch p are such that the least absorbed wave on passing through the cell has an ellipticity equal to or greater than .pi./8.

Abstract: An adjustment mechanism is provided for manually positioning and releasably locking a chair backrest in a desired vertical position relative to the chair seat. The mechanism comprises a guide rigidly secured to an upright backrest support frame of a chair and a channel rigidly secured to the backrest. The channel is mounted for vertical sliding movement on the guide. The channel comprises a slot having a plurality of vertically arranged notches along one vertical edge of the slot, an inclined surface sloping downwardly from the lowest notch at the bottom end of the slot, and a cam surface, partially straight and partially curved, extending upwardly along the other vertical edge of the slot from the lower end of the inclined surface to the highest notch. A latch bar is pivotally mounted on a pivot pin on the guide and has a latch pin extending into the slot.

Abstract: A self-sealing expansion rivet assembly comprises an expandable hollow plastic rivet and a plastic drive pin therefor. The rivet has a head and a slotted expandable shank for insertion in aligned holes in sheets which are to be joined together. The drive pin has a head and a serrated shank which, when inserted in the rivet bore and axially drawn thereinto by a tool, causes the pin head to engage the insertion end of the rivet shank and effect outward expansion of the rivet shank to fasten the sheets together, as well as break-off of the projecting end of the pin shank. The pin shank serrations engage a serrated reduced-bore portion in the rivet to hold the pin and rivet together permanently. Integrally formed annularly-shaped conical flexible liquid sealing flanges are provided on the rivet on, at or near the rivet head. As the rivet is expanded by the tool, the sealing flanges are forced against the adjacent panel around the hole therethrough to form a leak-proof seal.

Abstract: A head cleaning apparatus wherein in a case formed to the same shape and dimension of a hard case of hard-cased floppy disk a cleaning sheet formed to the same shape and dimension of the magnetic disk of floppy disk is rotatably placed and a cleaning liquid supplier is provided to the case to supply the cleaning liquid to the cleaning sheet as the cleaning liquid is injected under pressure from outside.

Abstract: An optical beam scanning apparatus wherein a beam shaping device for forming a flat light beam which has a large width in the scanning direction and which is substantially parallel with the direction of the optical axis is disposed between a light source and rotary polygonal mirror, and a cylindrical lens bent to have both ends in the longitudinal direction thereof approaching to the scanned plane is disposed between a condensing lens for condensing the light beam reflected by the rotary polygonal mirror and a scanned plane in the vicinity of the latter. The rotary polygonal mirror and the scanned plane are arranged to have a conjugate relation with each other from geometrical optics. The light beam is converged so as to generate the beam waist near the scanned plane.

Abstract: A shelving device wherein a side plate of a shelf is connected to a shelf plate through an insert attached to the side plate and an engagement member attached to the shelf plate. The insert has its portion buried and fixed in the side plate and is formed at one end of its buried portion with a generally trapezoidal receiving portion gradually narrowed upward and on both its sides with sloped faces. The engagement member has its engagement portion adapted to be buried and fixed in the lower face of one end portion of the shelf plate and is formed at one side of its engagement portion with an engagement recess gradually narrowed upward to fit the receiving portion therein and at both the sides of its engagement recess with a dovetail groove having sloped faces closely engaging the sloped faces on the two sides of the receiving portion.

Abstract: Apparatus which repeatedly severs wire segments from a wire strand and conveys them for further processing comprises a pair of wire feed clamps which are reciprocably movable in opposite directions to feed the wire strand along a first path. The wire feed clamps are affixed to parallel flights of a pulley-supported steel cable which is axially driven back and forth by an oscillatably rotatable cable drum. The cable drum is oscillatably driven by a rack-and-pinion mechanism which includes a drive rod or rack bar reciprocably movable by an orbiting crank pin on a support member which is adjustably mounted on a motor-driven rotatable feed crank. A locking mechanism releasably locks the support member and its crank pin in selected positions relative to the feed crank. The crank pin orbit determines drive rod stroke, cable drum position and wire feed clamp spacing and travel.

Abstract: The pane in a windowed fire retardant door is secured to the door by L-shaped metal clips which engage opposite surfaces of the pane and are nailed to the incombustible core of the door. The edges of the pane and of the hole in the door in which the pane is received are trimmed by bead strips that are nailed to the door. Each bead strip comprises a body of quadrangular cross-section of noncombustible mineral material and a plywood lamination bonded to that body over two of its longitudinal sides and a rounded corner at which those sides meet.

Abstract: A multi-speed power transmission utilizing ten gears, seven clutches and four shafts provides eight forward speeds and four reverse speeds. The transmission is coaxial in that the input and the output shafts are on the same centerline. The transmission requires only a minimum number of gears, clutches and shafts for the large number of gear ratios provided, and at the same time it is relatively compact and has only three shaft centers. In this transmission there are always three clutches applied in any speed range. Of the seven shifts between forward speed ranges, four of them require the engagement of one different clutch only, two of them require two different clutches to engage simultaneously, and one shift requires engaging three different clutches. The clutches are of the type having multiple friction plates, and hydraulically applied force pistons which are spring load returned. The clutches include appropriate ball dump valves in the force pistons.

Abstract: An exposure optical apparatus with two sets of wire pulleys disposed on both sides of a carriage for optical scanning of a document, the wire pulleys working for drive and control of the carriage, wherein two sets of fixed pulleys are provided on an apparatus fixed zone and laid on corresponding ends of the wire pulleys to a common wire, and a stopper member for determining an initial position of the carriage is provided on the apparatus fixed zone, thereby setting an initial posture of the carriage. The wires of both the wire pulleys are constituted of a common single wire, two sets of moving pulleys are provided on both sides of the document board carriage, and the wires are laid symmetrically on an axis of the center of the direction in which the document board carriage moves.

Abstract: An optical system of a reproducing apparatus having an exposure light source wherein the reflector of said exposure light source has a form of a curve of secondary degree and is adapted to be split into an upper half part and a lower half part at the non-reflecting surface of said reflector, said upper half part and lower half part being connected with a connecting member. The exposure device has a holding frame for holding an exposure optical system and guide members for movably guiding said holding frame. The guide members include an upper guide member disposed at the upper side of said holding frame and a lower guide member disposed at the lower side of said holding frame, said holding frame making a sliding contact with said lower guide member and contacting said upper frame member through an elastic member. On a lower position of said upper guide member is disposed an electrical collecting member.

Abstract: A manually operated valve is usable as a shut-off and stop/check valve for handling refrigerant fluids in a system subject to reverse fluid flow. The valve comprises a hollow valve body having fluid inlet and outlet ports, a valve plate within the body with a fluid flow passage therethrough, an annular valve seat on the valve plate around the passage, a hollow internally threaded valve stem sleeve attached to the valve body, a rotatable and axially shiftable externally threaded valve stem extending through the valve stem sleeve into the valve body, and a valve disc which is rotatably and axially shiftably mounted on the inner end of the valve stem and releasably engageable with the valve seat to open and close the valve. Rotation and axial shifting of the valve stem effects axial shifting of the valve disc to open and close the valve to enable it to function as a shut-off valve.

Abstract: A device for checking bent tubes by means of a probe, such as a pneumatically propelled eddy-current probe. The device comprises a sealing-tight enclosure adapted to communicate with the tube to be checked via a connecting tube. The introduction pressure of the probe is produced by a pneumatic circuit. The probe comprises a checking head and a cable having floaters and is wound on a coil driven by a torque motor. The introduction speed of the probe is controlled by passing it over a drive pulley, to which it is permanently applied by a strap tensioned by a spring, the pulley being mounted on the shaft of a constant-speed motor. Application to the checking of the tubes of heat exchangers, condensers and steam generators, more particularly of nuclear reacters.

Abstract: The power trowel of this invention has a chassis comprising a gear box and a prime mover and has a plurality of blades which engage a surface to be finished and which are driven by the prime mover, through the gear box, for substantially edgewise rotation about a vertical axis. An elongated handle for controlling movements of the machine across the surface has a pivotal connection to the chassis to be swingable up and down, but has an upper limit of such motion from which it is swingable downwardly. An elastically compressible shock absorber, confined between the handle and the chassis under compressive preload, tends to maintain the handle at that limit and is further compressed by downward force on the rear end of the handle. The center of gravity of the chassis is spaced forward of the vertical axis. Control of machine movements is minimally influenced by machine vibration, and is therefore more precise and less fatiguing.

Abstract: A head cleaning apparatus wherein in a case formed to the same shape and dimension of a hard case of hard-cased floppy disks a cleaning sheet formed to the same shape and dimension of the magnetic disk of floppy disk is rotatably installed. The cleaning sheet has microcapsules containing cleaning liquid on both sides of the sheet.

Abstract: The non-impact pile driver of this invention comprises a mast mounted on a trailer chassis and a carriage guided by the mast for vertical motion along it and comprising a hydraulic ram with a downwardly projecting piston rod. The carriage is raised and controlledly lowered by means of a winch. Horizontally movable latch members on the carriage, operated by remotely controllable hydraulic actuators, engage abutments on the mast, at spaced intervals along it, to lock the carriage to the mast. Thus the carriage can be lowered in stages for driving a substantially long pile.

Abstract: The present invention relates to a double barrier heat exchanger between a radioactive primary fluid and a secondary fluid making it possible to detect a possible primary fluid leak in the exchanger. The primary fluid circulates in a primary duct and the secondary fluid circulates in a secondary duct, a junction matrix being positioned between the primary and secondary ducts and in contact with the latter. The matrix is in the form of a compact metallic mass incorporating at least one element, e.g. silver, which can be made raidoactive when it diffuses into the primary fluid. Application is to sampling circuits in nuclear reactors.

Abstract: In a mixer having an elongated rotatable drum surrounded by coaxial front and rear tires, the invention facilitates adjustment of the positions of the two trunnion units that supportingly and drivingly engage each tire. Each trunnion unit comprises a base member horizontally shiftably slidable on the mixer frame and a tire engaging roller confined to rotation relative to the base member. Opening to front and rear ends of each trunnion unit are holes that are coaxial with its roller axis. Fixed to one side of the mixer frame are two locating fixtures, each having holes opening to front and rear end surfaces thereon, all of those holes having coinciding axes. Three U-shaped gages are provided, each having tangs which are closely receivable in said holes and which project laterally from opposite ends of an elongated lengthwise adjustable body portion. Two of the gages are used with the locating fixtures to position their adjacent trunnion units.