Abstract: In a display sign including a plurality of rotatable display elements to be flipped between opposite extreme display positions, a bidirectional limit stop for stopping the motion of said display elements at said extreme positions is configured in the form of a bidirectional pendulum. The limit stop is preferably formed by an oversize sleeve coaxially disposed with respect to and depending from a smooth-surface horizontally disposed support member. The rotatable display element is preferably generally planar and configured to strike the opposite sides of the outer surface of the pendulum-forming sleeve along a line passing below the point of support thereof. The resulting pivoting and rotating movement of the pendulum serves to absorb a substantial portion of the angular kinetic energy of the rotating display element, thereby suppressing rebound.

Abstract: An ejection mechanism for a tape recorder has a driving gear driven by a motor and an intermittent gear including a cam portion and disposed so as to engage with said driving gear, in which an operation link is driven through a commuting element having a follower, which is in contact with said driving gear and an eject lever is driven by said operation link so that an eject operation is effected by the motor, and is characterized in that a cassette guide and a pivoting frame for it are connected to an eject element interlocked with said eject lever, a cam edge of a swing lever being in contact with an engaging portion formed in said pivoting frame, a stopping portion and a locking portion being disposed at each of the sides of said cam edge, further including a spring energizing the eject force in the course of the cassette insertion and being disposed between said swing lever and the frame of the recorder.

Abstract: The pushbutton tuner includes a connection member which connects a memory slide plate for transverse displacement in response to tuning operation to a change lever responsive to the memory slide plate to actuate a tuning circuit element. The connection member particularly consists of first step for engagement with the memory slide plate, second step for engagement with the change lever, and a flat portion connecting the both steps.

Abstract: A miniature electrical fuse designed for at least 60 volt circuit applications in printed circuit application features protection against housing explosion under fuse blowing conditions by means of arc barrier-forming shroud members formed by confronting rigid arc barrier walls of base and cover members between which end terminals of the fuse are sandwiched. The walls form arc barriers which closely confront or contact the fuse wire on all four sides thereof ahead of the points where the fuse wire ends are connected to the terminals. These points of connection are advantageously out of alignment with the rest of the fuse wire. The terminals preferably extend from the confronting ends of the base and cover members where projections from the cover bearing on the terminals secure the terminals in place and seal the openings thereat.

Abstract: A door mechanism for a cassette insertion opening in an audio device comprises an inner door pivotally supported along one edge of the cassette insertion opening; an outer door pivotally supported along the opposite edge of the cassette insertion opening and having depressions formed along the edge remote from the pivotal axle and a packing member attached to the periphery of the inner face for forcible contact with the wall surrounding the cassette insertion opening; lock means consisting of lock arms engageable with the depressions of the outer door when the outer door is closed and unlocking arms actuated by the inner door when the inner door is fully opened, the lock means being always biased to the position for locking the outer door and being rotated to the unlocking position upon the actuation of the unlocking arms by the fully opened inner door and upon an operation of a door opening button provided on a front panel of the audio device, for example.

Abstract: A plug-in fuse assembly comprising a housing made of insulating material and includes upwardly extending side walls bridged by upwardly extending end walls, and a conductive plug-in fuse element secured in the housing. The conductive plug-in fuse element has parallel confronting terminals projecting downwardly from the bottom of the housing. The housing end and side walls uniquely have outermost vertical coplanar wall surfaces, preferably at the sides and top margins thereof, which are parallel to the housing sides involved and to the corresponding outermost vertical coplanar wall surfaces on the opposite end or side of the housing. The outermost vertical coplanar wall surfaces are adapted to engage the complementary outermost vertical wall surfaces of an identical plug-in fuse assembly placed with the identical end-to-end or side-by-side orientation besides it.

Abstract: An electrical fuse features a pyrotechnic smoke-generating mixture supported proximate to or adheringly supported on a meltable fuse wire element. A portion of the fuse housing is transparent. Upon either low current or high current blowout the local temperatures attendant thereto cause ignition of the pyrotechnic mixture and evolution of a cloud of colored smoke which deposits on the interior of the transparent portion of the housing to yield a readily visible indication that the fuse has blown. Additionally, when the fuse is operated at temperatures close to blowout conditions, a different colored smoke is produced to indicate incipient fuse deterioration.

Abstract: A completely mechanical disc film camera features film advance and shutter actuation by direct mechanical coupling to an external shutter release button. Shutter button actuation is automatically blocked after the fifteenth frame so as to prevent double exposure and film tearing. Selective film-flattening back pressure is applied to the disc film cassette during the terminal phase of the shutter depression stroke immediately prior to shutter tripping so as to hold the film in the proper imaging plane. Back pressure is released during the film advancing phase to as to relieve system loads and avoid film scratching. The film advance is secured by the oscillatory movement of a film notch engaging pawl carried by a claw driven into oscillatory motion by operation of the shutter button. Means are provided for coupling additional mass to the claw during the terminal phase of the film advancing stroke to reduce the speed of film advance, thereby providing protection against film overtravel.

Abstract: A surface acoustic wave device comprises a piezoelectric substrate, a pair of transducers provided on the piezoelectric substrate, a center electrode provided in the center between the both transducers, first shield electrode provided between one of the transducers and the center electrode, and second shield electrode provided between the other transducer and the center electrode, with placement substantially represented by: ##EQU1## where l.sub.1 is the width of the individual shield electrodes, l.sub.2 is the distance from the individual shield electrodes to the center electrode, .lambda..sub.0 is the wavelength of a surface acoustic wave at the center frequency, and n.sub.1 and n.sub.2 are whole numbers.

Abstract: A double-exposure prevention system for a still camera having a cockable spring-biased linear movable shutter-actuating slider operable between a cocked condition and held thereat by a latch movably responsive to a manually operated release member and thereafter upon release of the latch to a shutter-actuating position is provided with means for allowing one end of the slider to be rotated out of and away from the axis of the shutter-actuating movement throughout most of the subsequent rewind operation. While in this second angular position, the slider disables the operation of the release member, preventing accidental tripping of the latch after a cocking condition has been restored. During a small terminal portion of the film advance and after the preceding frame has been safely advanced so as to be out of the way, the film advance mechanism then rotates the slider back to its initial position.

Abstract: A subminiature power amplifier for hearing aids configured to be completely self-contained and fit within the user's ear features a Class D amplifier stage. By configuring all signal elements as digital units, circuit balance is readily maintained. A substantial economy of battery drain is achieved while preserving a low value of distortion at low signal levels. Oscillator frequency is governed by a single resistance element. The amplifier and an optional efficiency-improving inductor can be accommodated entirely within the residual volume of the motor chamber of a state-of-the-art earphone housing.

Abstract: A power line transient surge suppressor circuit features a nonlinear surge-bypassing network connected to bypass line surges around electrical loads connected to circuit output terminals. A fuse is inserted in series with the network, and blows in the event of short-circuit failure of a regulator device in the network. A thermal cut-out preferably of the irreversibly actuated type is inserted in series with the suppressor circuit input. A current-limiting heater resistor connected in parallel with the fuse supplies heat to trip the cut-out after the fuse blows, thereby permanently terminating power output to the loads. A similar suppression network is provided for the earth lead in three-wire systems.

Abstract: A display assembly for posters or signs includes a cover frame having a clear sealed window at the front surface thereof. The display assembly is generally rectangular, the cover frame having four outwardly facing walls configured to slide into forwardly extending closely fitting walls extending from a one piece wall-mountable shroud-forming frame. Magnetic strips affixed to interior faces of the shroud-forming frame capture and hold an inserted cover frame, and the closely fitting shroud walls and immediately confronting cover frame walls serve to defeat the insertion of conventional tools to remove the cover when so emplaced. A special spatulate tool is configured with projections stressed to spring out of the plane of the blade in the relaxed state. The extensions are temporarily pressed flat during insertion, to spring outward when inserted to maximum depth into the assembly, the extensions when thus deployed confronting and engaging a rear portion of the cover frame.

Abstract: A plug-in fuse assembly comprises a housing made of insulating material and having relatively closely spaced vertical side walls bridged by vertical end walls and a metal plug-in fuse element having laterally spaced, generally parallel confronting terminals at the bottom thereof projecting downwardly from the bottom of said housing and upwardly extending current-carrying extensions of said terminals and a unique S-shaped fuse link extending between said current-carrying extensions. The current-carrying extensions have upper vertical outer margins which are inwardly offset from a given point to the tops thereof with respect to the corresponding vertical outer margins of the plug-in fuse element below the same, to provide clearance spaces for the downward passage of the vertical end walls of the housing, so that the overall width of the fuse is not significantly increased, if at all, by the housing end walls.

Abstract: A wireless subscription television system arranged to transmit ciphered video signals from a transmitter to receivers in which the transmitting system comprises an enable code setting means, a transmitting means for transmitting control signals to allow a respective enable code of a receiving system to be picked up and a converting means for masking said enable codes and sending out masked enable codes, and on the other hand, the receiving system has a plurality of decoder systems each comprising a key code input means, a means for picking up a key code put in by the input means after converting it into an enable code by means of the control signals and a comparator means for determining if the picked-up enable code and the enable code as masked sent from the transmitting system are same or not. Thus, when the both enable codes come to be same, the respective decoder system is set in receivable condition.

Abstract: A tester for telephones and telephone answering systems features a dialing test capability for high speed dialing systems by providing the dialed digits in a single display element serially in time at a delayed rate set by strobing the digits from a memory storage element. A two-level ringing signal is provided to test for marginal telephone bell sensitivity. Means are further provided for reversing the emulation of the central office battery polarity so as to test for diode failure in electronic telephones. A simple cord circuit test for open- and short-circuit in the wall and handset cords, and moreover provides for detection of connector wiring reversal. Precision long-duration ringing burst capability is provided, along with ringback, dial tone, cut-out, and two-way communication between a telephone answering system under tests and a supplemental telephone as to provide for complete testing of the various phases of actuation of automatic answering systems.

Abstract: A bore examining apparatus comprises an article support, a reflector support on one side of the article support, a microscope body or other magnifying means on the other side of the article support, and a reflector mountable on the reflector support. The reflector is configured with a convex reflecting surface forming a solid of revolution about an axis coaxial with respect to the longitudinal axis of the bore being examined, the reflector facing the through hole when supported on the reflector support, so that the reflected image of the bore is directed towards the microscope and produces therein a 360.degree. panoramic view of the interior walls of the bore. The article support means is movable relative to the reflector support and magnifying means so as to move the viewing field along the bore.

Abstract: A pitch modification system for signals received from a tape player converts analog signals received from the player to binary digital form and stores them in sequential addresses in a memory unit at a rate set by a first clock. Output signals are produced by sequentially reading the stored information at a different rate as set by the frequency of a second clock, the ratio between the two clock frequencies causing the desired change in pitch with respect to the original signal. The output signal is converted from digital binary representation to an analog signal by a D/A converter. A detecting means is employed to detect no-signal conditions and generates an automatic reset signal which equalizes the two clock frequencies to restore the system to a zero-shift condition attendant to the appearance of silent passages on the tape.

Abstract: A cigarette holder has internal valving means for providing with each inhalation by the smoker an initial supply of substantially smoke-free air, followed by a vacuum actuated changeover to supply smoke directly from the cigarette without dilution. The initial precursor of substantially smoke-free air has a minimizing effect on the irritating properties of the inhaled cigarette smoke. An alternative embodiment incorporates the valving means directly into the end of the cigarette during manufacture.

Abstract: A film speed correction circuit for electrically controlled cameras having aperture or shutter speed controlled responsively to ambient light sensings from a photosensor features a controllable multi-stage amplifier preferably interposed between the photosensor and the aperture or shutter control means. The amplifier features a plurality of cascaded stages, each stage being operated to two different gain values according to a sensing signal provided thereto, the sensing signals for each stage being derived from coded insulating and conducting areas on the outer surface of the film cassette. Use of active stages interposed between passive attenuating stages substantially eliminates interstage loading and allows the use of standard resistance values to provided proper gain values for each stage.