Abstract: An optical communication system of a construction wherein the average wavelength dispersion value of the transmission optical fiber used, the optical output intensity of each optical amplifier repeater inserted in the transmission optical fiber and the widths of return-to-zero optical pulses transmitted over the transmission line are determined so as to compensate for the pulse compression effect by the nonlinear optical effect produced on the optical pulses by the pulse spreading effect by the wavelength dispersion effect. An optical multiplexer in the optical transmitting device time-division multiplexes the return-to-zero optical pulses, and the optical multiplexed signal is provided as an alternating-amplitude optical signal with the amplitudes of the return-to-zero optical pulses alternated.

Abstract: An optical transmitter which reverses the ON-OFF state of the optical intensity of a bright soliton lightwave and generates a dark soliton lightwave having an optical phase shift, an optical receiver for the dark soliton lightwave, and a superfast, high-capacity optical transmission system which is capable of increasing the soliton pulse array density while suppressing timing jitter. The optical transmission system is provided with the optical transmitter which transmits a dark soliton lightwave having digital information, the optical receiver which receives the dark soliton lightwave as a return-to-zero pulse and a transmission optical fiber interconnecting the transmitter and the receiver.

Abstract: A universal joint for coupling a pair of members with a connecting rigid link rockable about two sets of pivot axes. Each of the two members has a corresponding bolt hole through which extend respective stepped bolts defining two pivotal axes about which the link can pivot and rock. The link has opposite end portions each defining a loop through which extends a corresponding stepped bolt connecting a respective end of the link to a corresponding one of the two members the link couples. Each coupling bolt has a length with a major diameter extending axially through a respective coupled member and the corresponding loop of an end portion of the link to which it is coupled.

Abstract: An extrusion head having a stationary part fixed on an extrusion installation having a plurality of extrusion cylinders supplying an extrudate formed from several components. The stationary part has extrudate flow channels each in communication with a respective extrusion cylinder and a common extrusion die. Two pivotable outer parts pivotally hinged on the stationary part are selectively swingable individually between open and closed positions by respective piston-cylinder units. The two outer parts define an extrusion orifice for the die in their closed position. A pair of locking piston-cylinders provided with hammerhead piston rods hold the respective outer parts clamped against the stationary during an extrusion. Actuator piston-cylinder units selectively swing the piston rods of the locking piston-cylinder units clear of the outer parts for opening them for cleaning extrudate channels or for an extrusion die change.

Abstract: Here is disclosed a controller for operation of transmission in motor car comprising a control cable (14) of triple structure consisting of an outer tube (15), an inner tube (16) slidably inserted into the outer tube (15) and a length of wire (17) slidably inserted into the inner tube (16), characterized by that any one end of the outer tube (15) is fixed to a car body, one end of any one of the inner tube (16) and the wire (17) is engaged with a SELECT mode operating mechanism provided adjacent a control lever (6) while one end of the other one of the inner tube (16) and the wire (17) is engaged with a SHIFT mode operating mechanism also provided adjacent the control lever (6), the other end of the outer tube (15) is fixed to a transmission casing, the other end of any one of the inner tube (16) and the wire (17) is engaged with a SELECT mode operating mechanism provided adjacent a transmission unit while the other end of the other one of the inner tube (16) and the wire (17) is engaged with a SHIFT mode ope

Abstract: A high power laser transmitting fluoride glass fiber of an enhanced 2.94- .mu.m laser damage threshold value is disclosed, in which either of the core with a high refractive index and the cladding with a low refractive index is formed of fluoride glass which contains fluorine (F) as a component but has it substituted with 0 to 4.1 mol % of bromine (Br), chlorine (Cl), or bromine and chlorine. The optical fiber of the present invention may have its core formed of fluoride glass and its cladding formed of fluorine-contained resin, and the core glass has a composition that 70 to 80% of fluorine (F) is substituted with 0 to 4.1 mol % of bromine (Br), or chlorine (Cl), or bromine and chlorine.

Abstract: A valet constructed as a case having a top, sides and an open bottom. The case houses a sliding drawer having a front panel, sides constructed as frame slidable on support guides interiorly of the sidewalls of the case and also has an open bottom. A clothes hanger is pivotally mounted on a rod inside the drawer extending from one side to the other near the front panel. The hanger is pivotable upwardly into the drawer and held housed in the drawer by a bridge member disposed spanning the open bottom of the case so that the hanger rests slidable thereon and retained within the drawer when closed and can slide clear of the bridge member and depend downwardly when the drawer is opened for hanging clothing.

Abstract: A shear die is axially divided into a pair of die portions 18,19 between which a holding cavity 22 is formed, wherein the holding cavity has a diameter that is less than that of material "a" so that when one of the die portions is forced against the other die portion under a biasing effect of a spring 25, the material will be firmly held in the die cavity ensuring that the material can be cut to a predetermined volume and present a smooth cut surface, and the cutter arbor 4 is provided with a releasing member 34 adapted to release the one die portion 19 from the effect of the spring 25 as the cutter arbor 4 is retracted to facilitate additional material being moved into the die cavity for a subsequent cutting operation.

Abstract: A repeater which is installed as measures for silent zones, which automatically compensates for a variation in a light loss caused by a difference in length among optical cables interconnecting a master device and a plurality of slave devices which are allocated and installed in an underground shopping center or the like. The master device and the slaves devices both have current detectors for detecting current values of O/E transducers which transduce received lights to electric signals. Based on the detected current values, gain control signals are applied to variable gain amplifiers to change their amplification factors so that the levels of output RF signals for transmission to a radio base station and a portable station have a prescribed value, thereby compensating for the variation in the light loss of the optical cables. The present invention greatly facilitates the installation of the repeater and additional installation of slave devices.

Abstract: An energy-absorbing device for an automobile steering column having a body-tube housing the steering shaft. A support made as two parallel vertical members mountably fixed on a vehicle body mount the steering column axially between them. The body-tube has reinforcement members on two opposite sides. An attaching device compresses the reinforcement members in the support with a tightening non-rotatable bolt extending axially through the body-tube reinforcement members and the support members. A nut on one end of the bolt is tightened by an operator for establishing a determined level of a frictional force between the support and body tube.

Abstract: A device for collapsing a backrest of a backseat of a car for placing in communication a rear trunk with the passenger compartment of the car. The backrest is biased from an upright position to a collapsed position forwardly by a coiled biasing spring. A latch rod fixed to the backrest is received and held by a releasable latch of a backseat lock so that the backrest is releasably held in an upright position against the biasing force of the biasing spring. The lock is connected to a control cable operable manually from the vicinity of the front seat of the car or from the vicinity of the rear trunk to render the latch holding action ineffective and release the latch rod. The biasing spring will then collapse the backrest forwardly. The backrest is restored manually to an upright position and locked in readiness for collapsing by the biasing spring. The control cable has a flexible outer casing and an inner cable slidable longitudinally therein.

Abstract: An optical functional semiconductor element which performs ultrafast, high-contrast logic operation through utilization of the high speed of light velocity. A resonant-tunneling diode having a negative resistance characteristic is provided apart from a light absorbing layer formed by one of i-type layers of what is called a triangular barrier diode of an nipin or pinip structure, by which as the quantity of incident light increases, the quantity of transmitted current is switched from increase to decrease, the amount of change is made high-contrast and an ultrafast logic operation can be performed.

Abstract: An optical transmission system which permits long-distance, ultrafast, high-capacity optical soliton transmission by suppressing timing jitter with simple means. In an optical transmission system which uses a transmission line composed of an optical fiber for transmitting therethrough a lightwave signal having digital information added to a return-to-zero lightwave pulse and a plurality of optical amplifying repeaters for compensating for losses by the optical fiber and in which the pulse compression effect by the nonlinear optical effect on the optical pulse and the pulse expansion effect by the dispersion effect are compensated, at least one optical band limited element which has a flat group delay characteristic near the center frequency is disposed in the transmission line at intervals of a period Z equal to the soliton period Z.sub.sol and the product, aB.sub.sol.spsb.

Abstract: A mobile communication system is disclosed which precludes the necessity for mobile station to perform processing for microcell zone switching even when it moves from one microcell zone to another and which permits high-speed microcell zone handover. The service area of mobile communication is split into a plurality of macrocells; the macrocells are each subdivided into a plurality of microcells; a microcell base station equipped with a transmitting and receiving antenna and a power amplifier is installed in each microcell; a different communication channel is assigned to individual mobile station in the macrocell; even when the mobile station moves from one microcell to another, no channel handover takes place; and only when the mobile station moves from one macrocell to another, a mobile network control center which supervises the macrocell base stations effects channel handover.

Abstract: A speech circuit is disclosed which solves the serious problem of the degradation of the articulation of received speech voice in conventional circuits and permits pleasant communications at places where the background noise level is high. The circuit has a construction in which an input signal from a microphone is attenuated in correspondence to the background noise level to form a sidetone signal and a received speech signal from a speech channel is amplified in correspondence to the background noise level to form a new received speech signal.

Abstract: A driven massager of roller type for incorporation into a seat or backrest of a chair or into a mat as traveling massage unit. A traveling housing of the massage unit houses and carries drive and operating mechanisms for driving the traveling unit and operating a rotatable pair of elongate massage pressure rollers carried thereon disposed axially spaced in a common plane above the housing and driven alternatively in circular clockwise and counterclockwise motion while the traveling housing is stationary along a rectilinear path of travel or traveling thereon in two opposite directions on a pair of parallel gear racks laterally spaced defining the path of travel. The traveling housing is provided with driven paired gears on opposite sides for traveling on the gear racks.

Abstract: An optical amplifying-repeating transmission system is disclosed which is composed of an optical fiber for transmitting a lightwave signal with digital information added to return-to-zero lightwave pulses and a plurality of optical amplifying repeaters inserted in the optical fiber for transmission use. The mean value of wavelengths at which the wavelength dispersion of the optical fiber is zero is smaller than the wavelength of the lightwave signal which is transmitted over the system. The accumulated wavelength dispersion value of the optical fiber tends to increase with the distance of transmission, from a macroscopic viewpoint. The optical fiber for transmission is divided into a plurality of sections.

Abstract: An optical transmitter which reverses the ON-OFF state of the optical intensity of a bright soliton lightwave and generates a dark soliton lightwave having an optical phase shift, an optical receiver for the dark soliton lightwave, and a superfast, high-capacity optical transmission system which is capable of increasing the soliton pulse array density while suppressing timing jitter. The optical transmission system is provided with the optical transmitter which transmits a dark soliton lightwave having digital information, the optical receiver which receives the dark soliton lightwave as a return-to-zero pulse and a transmission optical fiber interconnecting the transmitter and the receiver.

Abstract: A speech coding transmission system is disclosed in which a coder of a differential coding system quantizes a difference between a predictive value from an adaptive predictor and an input speech signal by an adaptive quantizer in accordance with the level of the latter and to send out the resulting coded signal to transmission medium, and a decoder outputs a reproduced speech signal on the basis of a residual signal obtained by inversely quantizing a received coded signal with an inverse adaptive quantizer and a predictive value from an adaptive predictor. Both or either one of the coder and the decoder includes a comparator-attenuator which attenuates the amplitude of the input signal or reproduced speech signal to a value smaller than a predetermined threshold value and applies to the amplitude-attenuated speech signal to the adaptive predictor.