Abstract: A chain saw guide bar is formed of two metal plates of uniform thickness and of like size and shape. Each of the plates has local areas displaced from the plane of the plate to form protuberances on the inner face of the plate and corresponding recesses in the outer face. The protuberances are spaced from one another both laterally and longitudinally of the plate and comprise rows of protuberances which are spaced inwardly from opposite side edges of the plates a distance slightly greater than the length of the tangs of a saw chain to be used on the guide bar. The two plates are superposed on one another with the protuberances of one plate engaging matching protuberances of the other plate. One of the protuberances of each pair of matching protuberances has an integral tubular projection extending through a hole in the matching protuberance and riveted over in the corresponding recess to unite the plates in a unitary structure.

Abstract: A speed governor for an internal combustion engine comprises a flexible reed having a portion overlying the air intake aperture of the carburetor. The overlying portion of the reed is movable by flexing of the reed from a normal open position to a closed position in which it at least partially blocks the air intake aperture. The reed is tuned to vibrate at a frequency approximately equal to that of air intake pulses at selected maximum engine speed. As the engine speed approaches the selected maximum, the air intake pulses induce resonant vibration of the reed so as to bring the overlying portion intermittently into closed position. The air intake of the engine is thereby reduced so as to limit engine speed in part by providing a lesser charge and in part by increasing the fuel/air ratio to the point where engine power is reduced.

Abstract: Apparatus for finish casting of bifocal ophthalmic lenses from plastic material is described. No further surface grinding or polishing of the lens is required. The portion of the bifocal segment of the lens may be adjusted to any desired location relative to the optical center of the distance field of the lens. The apparatus comprises a power mold having a predetermined spherical or sphero-cylindrical surface, a bifocal mold having a predetermined optical curvature with a bifocal segment having a different optical curvature countersunk in the face thereof, and an annular gasket coupling the power and bifocal molds. The bifocal segment is adjusted relative to the optical center of the cast lens by use of a wedge member. An illustrative calculation to determine placement and thickness of the wedge for a given ophthalmic prescription is set forth.

Abstract: A stringer for a slide fastener has a continuous filamentary coupling element attached to an edge of a tape with a pair of spaced elongated members, such as textile cords, interposed between and secured to leg portions of each section of the coupling element. The spaced pair of elongated members provide stability to the continuous coupling element.

Abstract: The exhaust port of a spark ignition two cycle engine has the general shape of an inverted T with a base portion and a narrower upwardly extending stem portion. The top of the base portion is approximately at the level of the top of the transfer port which admits fuel-air mixture to the engine cylinder. The top of the stem is from 20.degree. to 55.degree. of crankshaft rotation in advance of the opening of the transfer port. This configuration of the exhaust port produces a low broad blowdown pulse which in turn results in a low noise level of the exhaust.

Abstract: A centrifugal clutch comprises a clutch drum and a one piece rotor of resilient material. The rotor has a central hub portion and two like weight portions on diametrically opposite sides of the hub. The weight portions are connected to the hub by integral curved spring portions which are relatively long so as to have a relatively low spring constant. The spring portions are of selected varying widths along their length so as to provide substantially equal fiber stress throughout the length of the spring portions when they flex under the action of centrifugal force on the weight portions to bring them into engagement with the inner surface of the drum and are subjected to driving force transmitted through the spring portions from the hub to the weight portions and hence to the drum.

Abstract: A helicopter having a lift unit including a multiblade helicopter main rotor system and a nodalized module including a beam driven in response to blade developed vertical forces has a fuselage unit connected to the beam only at vibration nodal points along the beam. The coupling between the lift unit and the fuselage comprises two rigid arms which form the beam and which extend toward one another from the nodal points. A multilayered flexible beam section interconnects the arms to accommodate beam bending in the flexible section. A rigid member is attached to each of the arms at drive points intermediate the nodal points in supporting relation from the lift unit.

Abstract: The bi-directional saw chain is made up of two links, a cutting link and a connecting link. The cutting link is symmetrical about its vertical center line and includes an L-shaped cutting section having cutting surfaces along both the leading and trailing edges. Legs extend outwardly from the cutting link on either side of the cutting section. These legs terminate in a surface which acts as a depth gauge. Each leg also includes a stop shoulder for engagement with the connecting link. The connecting link includes two offset and parallel sections, each having an outwardly extending flange. The outwardly extending flanges of adjacent connecting links form side by side parallel and spaced flanges which accommodate a perimetric trackway on the saw blade. Each connection is pivotal so that the leading leg acts as the depth gauge and the trailing leg engages the connecting link to form the stop and position the cutting link for proper functioning.

Abstract: A grip-yoke assembly for attaching a helicopter blade to the mast of the helicopter rotor having a conventional primary coupling to carry the centrifugal loads and a redundant path operative should the primary coupling fail to insure continued operability of the blade. In one embodiment, the redundant load path has a bearing surface formed on the inboard end of the grip and a corresponding thrust bearing mounted on an inboard yoke fitting for engagement with the bearing surface upon failure of the coupling. In an alternative embodiment, a bearing surface is formed on an outboard grip fitting and a corresponding thrust bearing is supported on the yoke outboard of the grip fitting.

Abstract: A self-tapping fastener and method of manufacture wherein said fastener is provided with a unique tapping section, in addition to a driving head and an intermediate threaded portion of generally conventional design. The tapping section is defined by a plurality of interrupted thread turns of an asymmetrical configuration. Each turn includes a pair of diametrically opposed lobe portions, with a pair of opposed side portions disposed intermediate said lobes. One said side portion is defined by a complete absence or void of material provided by a gap of controlled dimensions, while the other is provided by a thread form of an incomplete or under-filled configuration. The fastener of the invention is fabricated by rolling a specially designed blank between a pair of standard thread rolling dies.

Abstract: In producing a dyeable coating on a metal article, such as a slider on a slide fastener, the article is coated with a powdered solid polymer resin containing active proton acceptor groups, such as amine groups. The powder coating is heated to convert the powder coating into a polymer film which is capable of being dyed by any of a wide variety of dyes to produce a desired color in the polymer film. During the heating, the temperature is maintained below the temperature at which substantially all the active proton acceptor groups would be transformed or rendered inactive.

Abstract: The nickel-cadmium battery monitor is provided with sensors for measuring the battery temperature, the battery voltage and the magnitude of the current being charged to the battery, each of the sensors generating a sensor signal voltage that varies directly with the magnitude of the parameter being measured. The sensor signal voltages from the temperature sensor and the voltage sensor are conditioned and then converted to an analog signal voltage increment the magnitude of which corresponds approximately to the actual magnitude of the battery temperature and battery voltage as measured. The analog signal voltage increments thus obtained cause an analog visual display means to indicate visually the approximate magnitude of the battery temperature and battery voltage as measured.

Abstract: In eliminating one-per-rev vibration in a helicopter due to rotor unbalance, a one-per-rev vibration signal manifestation of rotor unbalance is generated and sampled when the rotor blades are successively in alignment with a reference direction during each cycle of rotation of said rotor. A difference signal is generated from the samples to represent by magnitude and phase the character of the unbalance. The rotor is modified in magnitude proportional to the magnitude of the signal and in direction dependent upon the span and chord components of the signal. In one aspect the force track error signal is applied to the input of a cyclic pitch control actuator system dynamically to automatically correct span unbalance forces.

Abstract: The invention contemplates selectively securing a bearing ring or the like to a cylindrical shaft, using a collar rotatably carried on a slotted end of the bearing ring. The collar bore and the collar-overlapped part of the slotted end have substantially conforming contours; in the case of the ring contour, a minimum radial extent characterizes the angular region of any slot, and a maximum radial extent characterizes an angularly offset location which, for the case of a two-slot ring, involves maximum radial extent angularly intermediate the slots. Various forms are described.

Abstract: A blind fastener wherein a push-pull type setting tool is employed for pulling a stem into a predetermined position relative to a sleeve, and a two element shear washer is provided to fail at a predetermined shear load as created by the compressive load on the sleeve and the reaction tensile pull on the stem. Failure of the shear washer drives a locking collar between the stem and sleeve.The shear washer comprises a pair of concentric but axially offset elements joined together by an annular shear web which, upon shear failure allows one of the elements to drive an annular locking collar between the stem and sleeve. Such shear washer together with the rivet sleeve are serially placed under compression to counteract the tensile force applied to the stem.

Abstract: Apparatus and method for installing a slide fastener with or without a slider and pull assembly to material wherein specially arranged and spaced pairs of pins pierce the adjacent edges of the carrier tapes of the slide fastener prior to the slide fastener being bonded to material.

Abstract: There is disclosed methods and apparatus for proving fluid meters, particularly gas meters of the positive displacement, diaphragm-operated type in which the number of cycles of operations of the valve mechanism of the meter is used as a factor in proving the accuracy of the meter, the number of said cycles being determined by sensing a series of pressure waveforms in the test gas entering and leaving the diaphragm chambers of the meter, which waveforms are characteristic of the particular meter being tested and occur in each cycle and reoccuring cycle of operation of the meter when operating, detecting a characteristic waveform in each series of waveforms, amplifying and shaping the characteristic waveform and counting a predetermined number of cycles of said waveforms and comparing the volume of test gas which has passed through the meter as measured by a test bell with the amount that should have passed during that predetermined number of cycles of operations of the meter.

Abstract: A nail constructed with conventional heading equipment with an open-sided partially circular head having a recess along the open-sided edge thereof to permit burr growth without interfering with the interengagement of a downwardly facing abutment surface of the head with a mating top surface abutment area when a plurality of such nails is collated and secured in an angle stick package with the shanks and heads of adjacent nails in abutting relation.

Abstract: Urethane prepolymer compositions are made from 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl cyclohexane and polyols at a total NCO to OH ratio of at least 1.2:1, and the prepolymers are reacted with cycloaliphatic polyamines to give urea-urethanes. The urea-urethanes can be formed as films such as coatings on a substrate or as indpendent sheets or the urea-urethanes can be formed materials of greater thickness. The products exhibit good strength, high resistance to the discoloring effects of ultraviolet light, elastomeric and other desirable properties. Often the urea-urethane is prepared in solution but this may not be the procedure where the urethane prepolymer and polyamine are combined and more or less immediately placed in the desired form as a film or other article such as is done using a two component spray gun.The polyol component of the composition has as its major component aliphatic polyol having a molecular weight of at least about 500.

Abstract: A personal information system wherein an illuminated information source is viewed in a mirror located closer to the eye than the shortest focal length to present in focus a visual image to the eye so that it can be viewed unobtrusively superimposed over the existing visual scene during normal activities. In a further aspect, the invention provides reflected illuminated symbolic presentation for speech interpretation assistance.