Abstract: An improvement in intumescent compositions is provided comprising, in part, melamine formaldehyde resin, a cross-linking agent, and a hydrophilic setting agent. The composition chemically absorbs water to yield an intumescent material with reduced cracking properties which decomposes into gas and a solid foam residue upon heating.
Abstract: An expansive solidifying material which consists of gypsum, blast furnace slag and portland type cement as the main components and soluble aluminate as a hardening promoter. The expansive solidifying material of the invention is quite suitable for solidifying poor grounds containing much water and the solidifying material is quite excellent in the initial hardening, long term strength, water absorption, expansibility and the reduction of production cost.
Abstract: A system of wholly passive or static elements for increasing laser pulse rate by interleaving the pulses of a plurality of beams of pulsed laser radiation. The system of static elements includes an array of beam splitters which are operative to receive a plurality of beams of pulsed laser radiation and provide a plurality of output beams, each sharing the radiation in each of the input beams. The invention includes a methodology for expanding the array of beam splitter elements to combine any number of input beams, of whatever differing characteristics, to provide a corresponding number of output beams, each sharing a portion of the radiation in each of the input beams.
Abstract: Two identical header tube members are fitted to opposite ends of an absorbing member with a plurality of internal channels for circulation of a heat transport fluid to form a collector element. Each header has a header tube which is spaced from a header base plate by a tube saddle. The perimeter of the element includes a flange for joining it together with other, identical elements. Any number of such elements may be joined together to form a continuous, watertight sheet. Where the header tubes of adjoining elements connect, their spacing from the base plate leaves a passageway under them between adjacent tube saddles. Water can run off the surface through the passageway in the direction of slope of the surface upon which the sheet of elements is installed.
December 6, 1978
Date of Patent:
May 5, 1981
Datwyler AG.Schweiz, Kabel-, Gummi- und Kunststoffwerke
Abstract: Mold, particularly for rigid polyurethane foam articles having finished textured surfaces on all sides thereof comprising a female mold having a recess into which the unreacted and unblown resin system is deposited and a cover for closing the mold together with a release sheet structure disposed therebetween exhibiting sufficient gas porosity to enable complete venting of air displaced by the rising foam in the production of a finished surface thereat and method of molding therewith.
Abstract: In an injection-locked laser system, a timing system for assuring the locking of an injection-locked oscillator to the frequency of a master oscillator. The system automatically controls the firing of the injection-locked oscillator in accordance with the difference in time between the production of a master oscillator pulse and the time that a predetermined population inversion level has been reached in the injection-locked oscillator as measured by a predetermined level of fluorescence produced by the injection-locked oscillator.
Abstract: Method and apparatus for sputtering particles of plural isotope types to produce a particle flow of the plural isotope types into a region where laser radiation is generated to produce isotopically selective ionization of at least one isotope type in the sputtered particle flow. Separate collection of the ionized particles is accomplished through application of a magnetic field in the region of ionization and beyond.
Abstract: A piezoelectric actuator and a control circuit therefor to apply a charge to the actuator proportional to an input signal magnitude. The charge controlled actuator achieves a more linear input-displacement response with reduced hysteresis.
May 17, 1979
Date of Patent:
April 21, 1981
The Charles Stark Draper Laboratory, Inc.
Abstract: A data modem is provided which is operative at a data rate of 4800 bps and employing 8 phase DPSK modulation. The modem includes a microprocessor and associated memories for digital signal processing and control of substantially all transmitter and receiver operations.
Abstract: An articulated, body-steerable sled, particularly useful as a child's recreational sled, provides the user with a high level of protection against pinching and collision. In a preferred embodiment, the sled comprises two or more sled body units flexibly coupled together by a hinge. A cover plate locks over the hinge to hold it in position and covers the region between the two units to protect the user from pinching. Contoured portions in the sled body units permit the user to steer the sled with his body and, at the same time, protect his body against collision.
Abstract: Apparatus and method for supplying feedstock to a reservoir containing material having a portion which is heated to a molten condition and vaporized by an electron beam. The electron beam is supplied from a heated filament and directed to impact on the vapor source material by electric and magnetic fields. The feedstock is suspended above a portion of the reservoir out of the path of the electron beam. Skip electrons along with some secondary electrons emitted from the surface of the material in the vicinity of the region of electron beam impact, together with radiant heating therefrom, are utilized to melt an exposed portion of the feedstock, allowing it to drip into the reservoir, and replenish the supply of material which is depleted by vaporization. Vaporization is maintained substantially uniform from the region of electron beam impact and splatter of the feedstock is largely avoided.
Abstract: An antenna system for use in an electronic security system and having a transmitting antenna with at least one loop lying in a plane, and a receiving antenna having at least two twisted loops lying in a common plane with each loop being twisted 180.degree. and in phase opposition with each adjacent loop. The transmitting and receiving antennas are disposed in spaced substantially parallel relationship across an aisle or passage through which a resonant tag circuit must pass for detection.
Abstract: A system for making optimum use of frequency shifted radiation by extracting both front and back travelling frequency shifted radiation beams. The two extracted laser beams are later combined in the same polarization for energization of a dye laser channel or cell for increased pumping efficiency in the dye laser operation. Additionally, where the generating cavity for the two beams is mode locked, the two extracted beams may be applied to the dye laser cell in time staggered manner in order to maintain the stability of subsequent amplification stages between pulses.
Abstract: Method and apparatus for the formation of a molded article from powders and powder compacts of a material by pressure compaction of the powders under the influence of a thermally driven differential volume expansion of first and second elements constraining the powders. The volume expansion achieves a trippling of the compaction effect.
July 18, 1979
Date of Patent:
April 7, 1981
The Charles Stark Draper Laboratory, Inc.
Abstract: An aqueous adhesive liquid with pronounced bonding capacity is provided which bonds to a broad variety of material in concentrated and diluted strength and is suitable for use with matter subjected to stress and vibration.
Abstract: A passive infrared intrusion detection system including a mirror assembly having an array of plane mirrors disposed at respective angular positions to provide a wide field of view. A parabolic mirror confronts the plane mirror array and is disposed with an infrared detecting element at its focal point. Radiation received in the field of view is directed by one or more of the plane mirrors to the parabolic mirror which focuses the received radiation onto the detecting element which provides an electrical signal which is processed to provide an alarm indication of intruder presence.
Abstract: Method and apparatus for achieving isotopically selective adiabatic inversion, particularly for improved isotope separation efficiency. In a preferred embodiment for practicing the invention, chirped laser radiation induces photoionization of a vapor state material in isotopically selective excitation and ionization energy steps. A frequency sweep or "chirp" is provided in the excitation laser radiation at a controlled rate and over a range of frequencies which is limited to prevent loss of selectivity in the excitation. The frequency swept radiation has a theoretical capability of producing 100% inversion of ground state particles in the vapor. The features of the invention additionally permit excitation of a material to very high energy states useful in producing high frequency, ultraviolet lasing.
November 8, 1978
Date of Patent:
March 17, 1981
Jersey Nuclear-Avco Isotopes, Inc.
Charles T. Pike, Horace W. Furumoto, Lawrence A. Levin
Abstract: A system for temporal pulse shaping of laser radiation beams particularly for use as photoexcitation radiation in isotope separation. Each pulse of laser radiation is temporally segmented into two or more sections. The sections are superimposed after a delay in the leading one to augment the pulse intensity.
Abstract: A heating device, particularly useful for heating the end portions of hollow elongated objects such as thermoplastic hose or tubing, comprises an enclosure for substantially surrounding the end portion of the object, means for substantially immobilizing the end portion within the enclosure and means for directing a stream of heated gas around the inside and outside of the object along the length of the end portion. In a preferred embodiment, the enclosure is an insulated metal circular cylinder having at one end apertures for receiving thermoplastic hose and controlling gas flow. At the other end, the enclosure has an apertured conical member for insertion into the hose to immobilize it in axial alignment with the cylinder.
Abstract: The invention comprises a method and apparatus for the tuning of a piano and other similar musical instruments to equal temperament. A transducer is operative to receive two notes being struck, one of which is tuned and the other of which is to be tuned. The electrical output signal provided by the transducer is processed by bandpass filtering to isolate a predetermined beat note which is associated with the two notes being struck. The filter output signal is applied to an output transducer such as headphones which provides an audible rendition of essentially only the intended beat note.