Patents Assigned to Canadian Patents and Development Limited
  • Patent number: 4783850
    Abstract: Optoelectronic switching matrix which switches multiplexed input signals to narrowband output lines. Each crosspoint of the matrix is comprised of a heterodyning photosensor, which optically receives the multiplexed input signal and electrically receives a selectable local oscillator signal. The difference frequency can thus be selected to be within the passband of a low pass filter whereby narrowband output signals can be received from the input signals without requiring the use of a demultiplexer.
    Type: Grant
    Filed: March 7, 1984
    Date of Patent: November 8, 1988
    Assignee: Canadian Patents and Development Limited-Societe Canadienne des Brevets et D'Exploitation Limitee
    Inventors: Robert I. MacDonald, Kenneth O. Hill
  • Patent number: 4781796
    Abstract: An apparatus for the conversion of sludge including a heated continuous tubular member having a continuous conveyor extending therethrough and defining along its length in succession a heating zone, a connecting zone and a reaction zone. The connecting zone conveys solid products from the heating zone to the reaction zone without substantial passage of gaseous material therethrough, and a duct means separate from the tubular member connects the heating zone and the reaction zone for the passage of gaseous products from the heating zone to the reaction zone.
    Type: Grant
    Filed: May 7, 1987
    Date of Patent: November 1, 1988
    Assignee: Canadian Patents and Development Limited
    Inventors: Trevor R. Bridle, Herbert W. Campbell
  • Patent number: 4776658
    Abstract: New all-optical modulators that use nonlinear refraction and absorption to modify fiber-to-fiber coupling are disclosed. No resonators, feedback or stringent wavelength controls are needed. Implementations of the AND, NOR, NOT and XOR gates with better than 20 dB contrast ratio are described and demonstrated.
    Type: Grant
    Filed: July 30, 1987
    Date of Patent: October 11, 1988
    Assignee: Canadian Patents and Development Limited
    Inventor: Richard J. F. Normandin
  • Patent number: 4769818
    Abstract: A method of, and apparatus for, encoding and decoding a sequence of data bytes to permit correction of bit errors occurring in one byte of the sequence, or two bytes providing that the two incorrect bytes can be identified (for example if the bytes show parity failure). Each data byte of the sequence comprises data bits and one parity check bit. To encode the sequence of data bytes two "Code C" code bytes are determined from the data bytes, according to predetermined relationships, the data bytes and code bytes together forming an encoded data block. Also, there is provided a method of, and apparatus for, encoding and decoding a bundle of data blocks to permit correction of a number of bit errors occurring in bytes of the bundle. (Conceptually, the bundle of data blocks comprises a stack of data blocks, one positioned under another to form a two dimensional array of bytes.) Data block bundle encoding consists of separately encoding rows (i.e. horizontal encoding) and columns or pairs of columns (i.e.
    Type: Grant
    Filed: November 21, 1986
    Date of Patent: September 6, 1988
    Assignee: Canadian Patents and Development Limited-Societe Canadienne Des Brevets et d'Exploitation Limitee
    Inventor: Brian C. Mortimer
  • Patent number: 4763977
    Abstract: An optical coupler for single mode optical signals having a tunable (variable) coupling ratio, and a method of fabricating the coupler. A pair of virtually identical optical fibers are fused together at a narrowed waist region, each fiber being formed of a core and cladding, each being tapered toward the waist in such a manner as to ensure adiabatic propagation of light in the structure. An optical signal carried by one fiber first passes through a decreasing taper region and then passes through an increasing taper region of one or the other fiber (or both). The decreasing taper rate of the input portion of one fiber is such that the optical signal radiates out of the core (where V=1 locally) and into the cladding, as it approaches the waist. The increasing taper rates of the output portions of the two fibers are such that a predetermined coupling ratio is obtained.
    Type: Grant
    Filed: January 9, 1985
    Date of Patent: August 16, 1988
    Assignee: Canadian Patents and Development Limited-Societe
    Inventors: Brian S. Kawasaki, Masao Kawachi, Kenneth O. Hill, Derwyn C. Johnson
  • Patent number: 4764052
    Abstract: A breakwater comprised of an array of aligned perforated-wall caissons having a slab bottom standing on a pervious rubble base and anchored by its own weight incorporates exceptionally heavy ballasting to ensure stability under attack by large waves, i.e. to that the ratio of maximum horizontal thrust force to downward vertical force is below about 0.46.The immersed wall height is much reduced so that the slab bottom lies below mean sea level about 1.3 to 1.7 times the height of the greatest wave predicted, lessening costs of construction and siting. Efficient energy dissipation function is preserved by placement of augmenting mass below the height of the wave trough and by providing flow passages for jets directed by front wall ducts, avoiding increase of reflection coefficient.
    Type: Grant
    Filed: May 8, 1987
    Date of Patent: August 16, 1988
    Assignee: Canadian Patents and Developments Limited/Societe Canadienne des Brevets et d'Exploitation Limitee
    Inventor: Gerard E. Jarlan
  • Patent number: 4757202
    Abstract: This invention provides a direct reading solid-state dosimeter which will measure neutron and gamma radiation. A dual metal-oxide-semiconductor field-effect transistor (MOSFET) is used as a gamma sensor and a forward biased PIN diode as a neutron sensor. A liquid crystal display is provided for displaying the gamma and neutron radiation dosage.
    Type: Grant
    Filed: July 10, 1986
    Date of Patent: July 12, 1988
    Assignee: Canadian Patents & Development Limited
    Inventor: Philip C. East
  • Patent number: 4756748
    Abstract: A process for the smelting reduction of oxide ores, in particular iron ores, employs a mixture of the finely divided ore with equally finely divided reductant, which in the case of iron ores preferably is a coal. The mixture is fed into the interior of a heated tubular reaction vessel and moved positively through a heated reaction zone by a screw conveyor embedded in the charge. The conveyor breaks away any accretions that stick to the wall before they can build to a size that will stall the conveyor. The particles are in the range 75-1400 micrometers with a preferred size of at least 95% less than 600 micrometers, and the preferred ratio of ore to reductant is in the range of ratios 18:82 to 30:70. The reduced iron can be fed directly into a melting furnace for separation of metal and non-metal, it can be powdered and separated magnetically or it can be briquetted.
    Type: Grant
    Filed: April 2, 1987
    Date of Patent: July 12, 1988
    Assignee: Canadian Patents and Development Limited--Societe Canadienne des Brevets et d'Exploitation Limitee
    Inventors: Wei-Kao Lu, Czeslaw Bryk
  • Patent number: 4755459
    Abstract: Monoclonal antibodies specific to Neisseria gonorrhoeae lipopolysaccharide components having no cross-reactivity with N. meningitidis have been produced and found useful in the diagnosis of the presence of N. gonorrhoeae.
    Type: Grant
    Filed: June 10, 1985
    Date of Patent: July 5, 1988
    Assignee: Canadian Patents and Development Limited
    Inventors: Terry W. Pearson, Malcolm B. Perry
  • Patent number: 4754645
    Abstract: A method and an apparatus for ultrasonically characterizing polymer materials under simulated processing conditions are disclosed. According to the invention, a sample of a polymer is held in confinement between two axially aligned buffer rods having opposed parallel end surfaces spaced from one another to define a gap filled with the polymer sample, the polymer sample being acoustically coupled to the opposed end surfaces of the buffer rods. Ultrasonic waves are transmitted through one of the buffer rods in a direction toward the polymer sample for interaction therewith, and the polymer sample is subjected to controlled temperature or pressure variations over a predetermined period of time, the variation in temperature or pressure being effected via the buffer rods.
    Type: Grant
    Filed: May 14, 1987
    Date of Patent: July 5, 1988
    Assignee: Canadian Patents and Development Limited
    Inventors: Luc Piche, Francoise Massines, Andre Hamel, Christian Neron
  • Patent number: 4754654
    Abstract: There is described a submersible water sampler for use in the collection of samples for testing. Conventional in situ samplers have had the disadvantage that they have been bulky and difficult to handle. There is described an in situ water pump sampler which has a frame member attached to a hydrographic wire by a swivel. The sampler is self-contained and is mounted through a hub to a frame member to permit rotation of the sampler on the frame about an axis normal to the longitudinal axis of the hydrographic wire.
    Type: Grant
    Filed: January 8, 1987
    Date of Patent: July 5, 1988
    Assignee: Canadian Patents and Development Limited
    Inventors: Bruce D. Johnson, Peter J. Wangersky
  • Patent number: 4752140
    Abstract: A method for the detection of delaminated areas in coated materials or layered composites, which allows free-air operation and can be used to scan portions of bulky materials on the spot. This method which makes it possible to detect very small delaminated areas in a very short time (less than 1 millisecond), with a very high sensitivity and without creation of excessive thermal stress in the inspected material, basically comprises the steps of: focusing pulsed, thermal radiations onto the structure to be inspected to produce a vertical displacement of its coating by thermal expansion if a delaminated area is present at the coating-to-substrate interface, and detecting and measuring this vertical displacement if any, by interferometry, preferably laser-beam interferometry. An apparatus for carrying out this method is also disclosed.
    Type: Grant
    Filed: October 1, 1986
    Date of Patent: June 21, 1988
    Assignee: Canadian Patents and Development Limited/Societe Canadienne des Brevets et d'Exploitation Limitee
    Inventors: Paolo Cielo, Gerard Rousset
  • Patent number: 4749466
    Abstract: The invention is based on the discovery that in a solid electrolyte galvanic sensor, e.g. an yttria-stablized zirconia body, it is not necessary, as has hitherto been believed, to eliminate all impurities to achieve the important performance characteristics of rapid response time, reduced susceptibility to aging, and improved reliability. It has now been found that these improvements can be obtained by reducing only the concentration of iron oxide (and any other variable valence oxides that sometimes occur) in the sample, and that it is unnecessary to lower the concentration of oxides of fixed valence elements, such as silicon, aluminum, magnesium, and the alkali and alkaline earth metals, many of which tend to occur frequently as impurities in ceramic materials. This inventive selective elimination of only the variable valence oxides saves substantial cost in manufacture without loss of the performance advantages mentioned above. Indeed, better mechanical properties are often obtained.
    Type: Grant
    Filed: March 26, 1987
    Date of Patent: June 7, 1988
    Assignee: Canadian Patents and Development Limited
    Inventors: Charles R. Masson, Philip D. Pacey, Shi X. Dou
  • Patent number: 4742318
    Abstract: A birefringent single-mode acoustic fiber for propagating linearly polarized shear acoustic waves while preserving linear polarization, comprises an elongated core region of a solid material in which acoustic waves can be propagated in two orthogonal shear mode components, and a cladding region enclosing all surfaces of the core region except end surfaces thereof, the cladding region being also of a solid material in which acoustic waves can be propagated in two orthogonal shear mode components.
    Type: Grant
    Filed: March 19, 1987
    Date of Patent: May 3, 1988
    Assignee: Canadian Patents and Development Limited - Societe Canadienne Des Brevets et D'Exploitation Limitee
    Inventors: Cheng-Kuei Jen, Gerald W. Farnell, Ahmad Safaai-Jazi
  • Patent number: 4739028
    Abstract: Epoxy resins have been found to be fortified (increased in strength and modulus yet not made brittle) by compounding:(a) a resin-forming polyepoxide(b) an amine curing agent for (a) and(c) a fortifier for (a)+(b) comprising the reaction product of(i) an aromatic polyhydroxy compound and(ii) a diepoxide with one epoxy group less reactive than the other:and heat curing the mixture. Strengths as high as 140 MPa and moduli as high as 4500 MPa have been attained with a ductile mode of failure.
    Type: Grant
    Filed: March 2, 1987
    Date of Patent: April 19, 1988
    Assignee: Canadian Patents & Development Limited
    Inventors: Paul D. McLean, Andrew Garton, Robert F. Scott
  • Patent number: 4738795
    Abstract: Crude petroleum water-in-oil emulsions such as those produced by steam injection or water flooding in secondary oil well treatments (and other emulsions of this type) can be very effectively broken by the addition of water-insoluble, polar compounds selected from certain aliphatic carboxylic acids, alcohols, ketones including diketones, acetates, nitropropane, nitrobutane; and alkyl-substituted phenols; in small amounts up to about 8% by weight based on the emulsion. It was found that the number of carbon atoms in the aliphatic compounds and in the phenol's alkyl substituents must be within certain ranges for effective demulsification. The dispersed aqueous droplets, on treatment with the selected compound and appropriate agitation, come together to form an aqueous phase which can be separated. The additives can be recovered from the organic phase and recycled. Certain additive mixtures have been found very effective.
    Type: Grant
    Filed: September 27, 1985
    Date of Patent: April 19, 1988
    Assignee: Canadian Patents and Development Limited
    Inventor: J. Redmond Farnand
  • Patent number: 4737413
    Abstract: A chemorepellant compound is disclosed having a general formula ##STR1## where R.sub.1 is H or an alkyl group in the range C.sub.1 to C.sub.6, and R.sub.2 is H or an appropriate hydroxyl protecting group, and pharmaceutically acceptable salts and esters thereof. A preferred form of the compound where R.sub.1 is hydrogen and R.sub.2 is hydrogen is made by incubating linoleic acid with soyabean lipoxygenase or with cytosol associated endothelial cell derived lipoxygenase. The chemorepellant compound can be bound to a prosthetic surface via an intermediate linking species such as a protein and studies have shown that platelet adhesion onto in the vicinity of a thrombogenic surface is greatly reduced in comparison to non-chemorepellant coated surfaces.
    Type: Grant
    Filed: June 30, 1986
    Date of Patent: April 12, 1988
    Assignee: Canadian Patents and Development Limited
    Inventor: Michael R. Buchanan
  • Patent number: 4736808
    Abstract: In a percussive tool in which a very high pressure and preferably cavitating water jet is directed through an opening in the working surface of the tool, the jet is formed by a nozzle positioned in a cavity behind the opening and decoupled from the tool by a bearing layer of water from the jet. A supply pipe extends rearwardly of the nozzle without contacting the tool, and is supported externally of the tool, on a machine which operates the tool, by a support which allows the fluid bearing to center the nozzle within the cavity while restraining movement of the nozzle axially of the tool.
    Type: Grant
    Filed: October 14, 1986
    Date of Patent: April 12, 1988
    Assignee: Canadian Patents and Development Limited/Societe Canadienne des Brevets et d'Exploitation Limitee
    Inventors: Bruce James, John P. Dorscht
  • Patent number: 4736459
    Abstract: FM receivers which are very compact and simple yet have high sensitivity are described. The FM receivers are of the homodyne type or heterodyne type including a frequency converter. All the FM receivers contain two-termimal negative admittance networks.
    Type: Grant
    Filed: April 14, 1986
    Date of Patent: April 5, 1988
    Assignee: Canadian Patents and Development Limited
    Inventor: Cornelius M. G. Zwarts
  • Patent number: 4735158
    Abstract: A planting machine for planting containerized seedlings from a moving vehicle comprising a planting tool that is pivotally supported on the vehicle. The planting tool comprises a resiliently mounted ground engaging foot, a ground penetrating probe, and a planting container advancing device having a passageway for containers. The probe is reciprocatably mounted relative to the container advancing device with means to provide horizontal displacement of the container advancing device when the probe is withdrawn such that the outlet of the container passageway is positioned over the hole made by the probe for receiving the planting container.
    Type: Grant
    Filed: April 25, 1986
    Date of Patent: April 5, 1988
    Assignee: Canadian Patent and Development Limited
    Inventors: Lowell A. Paul, Alan Moss, deceased, Bruce R. Beaty