Abstract: A unidirectional drive assembly for a mechanically driven meter register includes a gear shift operated gear ratio mechanism which allows a dial on the meter register to be driven up-scale at a normal rate with the forward direction of rotation of the meter input drive and driven up-scale at a compensated or faster rate with the reverse direction of rotation of the meter input drive. The ratio of the gears of the gear ratio mechanism can easily be changed to provide ratios which compensate for meter drag when the meter is run in the inverted position so that the meter registers correctly when operated in either the upright or inverted position, or to provide ratios which make the meter dial run up-scale at a faster than normal rate when the meter is tampered with to make its input drive operate in the reverse direction of rotation.

Abstract: Loudspeaker equipment embodying a speaker, an enclosure for the speaker which is substantially closed except for the speaker opening and which is formed of walls which are thin and therefore capable of excitation and consequent sound generating vibrations under the influence of the speaker, the speaker equipment further including a reflector surrounding the speaker enclosure and having an open front through which the speaker is exposed, the walls of the reflector being spaced from the walls of the speaker enclosure to provide a passage through which sound generated by the walls of the speaker enclosure is reflected forwardly.

Abstract: A cone speaker is mounted to a horn within a reflex chamber behind a forward opening through the chamber, and the forward end of a horn is attached to the opening. The speaker is connected in the entrance discharging rearwardly into the chamber, and forwardly into the horn. The horn includes a restriction between the forward end of the horn and the speaker, and ports are formed through the horn, entering the restriction.

Abstract: A low cost, self locating auxiliary keyboard assembly is disclosed for changing the key configuration and classification of the keyboard of a data terminal device, the assembly including a cover member having a plurality of apertures which overlie associated control keys on the keyboard of the data terminal device. A classification indicia card having a plurality of predetermined positioned apertures is placed on the cover member, the apertures in the indicia card overlying certain of the apertures in the cover member to allow a removable auxiliary key member to be inserted within the aligned apertures of both the indicia card and the cover member to engage the top portion of the associated control key on the keyboard of the data terminal device for operation thereby.

Abstract: A phase plug structure is described which is an intermediate element between a conventional fiber cone loudspeaker and an exponential horn. The purpose of the phase plug is to equalize acoustical path lengths and thereby minimize high-frequency cancellations caused by phase differences. The design of the phase plug is based upon an analysis of both low-frequency and high-frequency horn behavior. A usable bandwidth of four octaves is obtained over a sharply-defined angle of radiation.In accordance with another embodiment of the invention, an enclosure is provided having a first exponential radiator, of relatively small size attached to the front of the speaker, and a relatively large exponential radiator coupled to the rear surface of the speaker for improved base response.

Abstract: A hub odometer having a pendulous recording mechanism with loose ball anti-orbiting means with two damping balls mounted within a radial ball track diametrally of the center of gravity of the pendulous recording mechanism and having a width in the circumferential direction approximately equal to but slightly greater than the total width of the two damping balls.

Abstract: An apparatus for developing diazo material according to a semi-dry process comprising an applicator roll with a liquid absorbing cover, a press roll having a grooved hard surface, a backing roll biased against the press roll, and a blade for reducing the amount of developer liquid on the applicator roll and the press roll. The press roll is displaceable toward the applicator roll. The plane of transport of the diazo material to be developed passes between the applicator roll and the press roll. The axial moment of inertia of the press roll relative to the axial moment of inertia of the applicator means is determined in accordance by an equation containing weight components of the press roll, weight components of the applicator roll, the contact pressure component of the backing roll, and the sum of the components of the tangential force and normal force of the contact pressure of the blade and the frictional force along the line of contact of the blade on the applicator roll.

Abstract: Instruments presently available for stereographic calculations use a single net over which transparent paper is moved. The device of this invention has two nets, one printed on each side of a rotatable disc in a frame and the calculations are made by rotating the nets under transparent paper fixed to the frame.

Abstract: A muffler incorporates a tubular shell that has an acoustically reflective interior circumferential surface. In successive sections taken transversely through the shell, the acoustically reflective surface has at least a portion of its circumference shaped to define at least part of an ellipse or a parabola. Between an inlet into and an outlet from the shell, a fluid flow path extends along an axis lengthwise through the shell. A sound absorptive treatment is disposed along a second axis extending lengthwise through the shell. The treatment is spaced from but communicates with the fluid flow path. At least one of the two axes is defined by corresponding focal points of successive transverse sections taken through the curvilinear portion of the circumference of the acoustically reflective shell surface. In operation, sound emitted from fluid flowing along the fluid flow path is reflected by the reflective shell surface to the sound absorptive treatment.

Abstract: The system responds to signals from a weight computer to depress selected keys on the postage metering machine keyboard. A solenoid is associated with each key. The solenoids are mounted on a carriage for movement toward and away from the keyboard. Spring bias and weight forces the carriage toward the keyboard. Energized solenoids hold an engagement tip extended so that when the carriage is released toward the keyboard, the carriage force will depress the selected key. The engagement tip on unenergized solenoids contact the key but the solenoid shaft moves upward into the solenoid without depressing the key.

Abstract: An apparatus for precisely moving a camera lens element to focus an image at the camera's film plane is disclosed. The apparatus employs an electrically controlled and incremently stepped rotating motor which moves a lens element parallel to the lens axis. The disclosed motor is an epicyclic motor, and a mechanical coupling arrangement interconnects a driven rotating motor element and the lens element holder and converts the rotary motion of the motor to incremental translation of the lens element. The apparatus moves the lens element in this manner in small precisely controlled increments, for example, steps of less than 0.001 inch.

Abstract: A sound insulation chamber delimits a gaseous flow channel and including onant cavities housed within a double wall. The cavity vents are ducts which open into the channel flush with the inner wall and project into the interior of the cavities.

Abstract: An acoustic headset having a pair of elongated channel structures for carrying sound tubes which are provided with ear pieces situated adjacent upper end regions of the channel structures. These channel structures have distant from their upper end regions, respectively, lower end regions interconnected with each other by way of a connecting structure which forms a continuous, elongated, one-piece body with the pair of channel structures. The connecting structure interconnects the pair of channel structures for movement toward and away from each other while a releasable holding structure is connected with the pair of channel structures for releasably holding them at a selected distance from each other, so that in this way it is possible for the ear pieces to be accommodated to the distance between the ears of a given individual.

Abstract: An improved circular sliderule for use in many applications wherein it is desired to provide a sliderule having superimposed disc elements which may be freely rotated without disturbing the previous setting of the adjacent discs. The novel improved calculator comprises providing a separating spacer element to be positioned between each disc of the calculator and with each spacer element having formed thereon means for retaining the rotation of the spacer element whenever superimposed discs are rotated. The retaining means may comprise a series of protruding arms, one extending outward from each of the separating spacer elements, joined at their outer ends and locked to the base plate of the calculator which is not rotatable. Alternately the retaining means may comprise the spacer element having formed on an internal hole at least one protuberance which is designed for mating engagement with an engaging means in the form of an elongated slot formed in the central hub which is locked to the baseplate.

Abstract: This invention relates to a cabinet for audio reproduction speakers of the type which have a movable speaker cone mounted within a fixed speaker frame. The cabinet includes a plurality of external cabinet members juxtaposed to form a substantially rectangular cabinet having a rectangular void therein together with front and rear openings. Each of the external cabinet members is formed from a thin and acoustically stiff material for moving in a vibratile mode when energized. End sections of adjacent ones of the external cabinet members define therebetween isolation slots for permitting the independent vibratile mode of each of the external cabinet members. Nodal couplers span the isolation slots for transmitting vibratile energy between adjacent external cabinet members.

Abstract: Method and apparatus for actuating a counting device for recording and stng data. The invention comprises an activator for a counter device and includes a mass or weight having an eccentric center of mass which is freely pivotable in one plane in response to an externally applied impulse force of a predetermined magnitude to apply a torque force to a shaft which, on rotation thereof under the influence of said torque force, activates the counter mechanism to record a count. Means are also provided to apply counter torque force of a constant predetermined magnitude or value to the shaft so that the counting device is actuated only in response to a resultant torque force of a predetermined magnitude or value generated by the impulse.

Abstract: The noise protection screen of the present invention comprises a plurality of hollow tubular members, preferably of equal length and substantially elliptical in cross-section. The hollow members are formed of a flexible material and inclined at an angle to the horizontal. The hollow members are interconnected by corresponding tongue-and-groove engagement whereby the engaged grooves are deformed in a manner to provide a clamping action of the grooves about the corresponding tongues.

Abstract: A driver unit for a horn type loudspeaker is disclosed. The driver unit comprises a dome-shaped diaphragm and an equalizer positioned on the concave side of the diaphragm. The equalizer has a convex surface adjacent the diaphragm and a plurality of slits extending from the convex surface to an interior, outwardly opening throat. The slits are disposed in equal angular pitch with the outermost slits being located at the edge of the convex surface of the equalizer. The outermost slits are approximately one half the width of the remaining slits, the remaining slits being of equal width.

Abstract: A speaker structure comprising a tetrahedronal shell having an upper end and an equilateral triangular base with equisized triangular walls and with the margins of the adjacent walls and base being secured together and wherein one of the walls includes a pattern of port openings and these openings are arranged about a central opening spanned by a speaker which is fixed thereabout.

Abstract: A cabinet for improving the sound output of an amplifier, the cabinet being in the form of an upright rectangular housing with a horizontal partition dividing the interior into an upper and lower portion, the partition having a speaker opening and a baffle opening, a speaker being mounted in the speaker opening for upward projection of the sound into the housing upper portion, the speaker being connected to the amplifier, a sounding board within the housing upper portion inclined at an angle from the housing rear upwardly towards the housing front, a sheet of metal affixed to the horizontal partition and covering the baffle opening, the vibration of the speaker serving to drive the metal baffle by condensations and rarefaction of the sound waves to either side of the horizontal partition so that the metal baffle functions as a supplemental and complementary sound source.