Peter Pisio, Charles F Kirkvold: System for recovering viscous petroleum from thick tar sand. Chevron Research Company, E J Keeling, R L Freeland Jr, April 26, 1977: US04019575 (245 worldwide citation)

Recovery of viscous petroleum such as from thick tar sands is assisted using a closed-loop flow path formed in a well by concentric casing and tubular members extending from the earth's surface through a substantial portion of the formation for conducting hot fluid to reduce the viscosity of the pet ...

Martin Bruce Fitzgerald: Heyer Schulte Corporation, Donald D Mon, April 26, 1977: US04019499 (213 worldwide citation)

A compression implant to resist the flow of urine through the urethra comprising a cap, an external planar pressure face on the cap, a base, an external bearing face on the base, and a peripheral wall continuously interconnecting the cap and the base. A peripheral fold in the peripheral wall enables ...

Donald D Maurer, Paul D Sorenson: Electrical stimulation system. Medtronic, Lindquist & Vennum, April 26, 1977: US04019518 (171 worldwide citation)

An electrical stimulation system for selectively stimulating portions of the body. The system includes an external device for alternately transmitting stimulus signals and control signals to an implantable receiver. The receiver includes a plurality of output devies adapted to apply the stimulus sig ...

Roger A Saunders: Multiaxis rotary joint for guided em waves. Rockwell International Corporation, Terry M Blackwood, Robert J Crawford, L Lee Humphries, April 26, 1977: US04020431 (146 worldwide citation)

An electromagnetic wave guiding rotary joint admitting of rotary motion about two or more axes. A spherical journal and a complementary spherical race afford electromagnetic communication between two wave guiding means.

Francis J Tenczar: Adhesively activated sterile connector. Dominik Knechtel Godula & Demeur, April 26, 1977: US04019512 (140 worldwide citation)

A sterile connector assembly for moving blood component preparations through a fluid path established by engaged coupling elements within adjoined connectors. The open end of the connectors are closed by barrier membranes covered by protective members with adhesive film between the protective member ...

Ronald Eldon Crochiere, Lawrence Richard Rabiner: Interpolation-decimation circuit for increasing or decreasing digital sampling frequency. Bell Telephone Laboratories Incorporated, A E Hirsch Jr, Robert O Nimtz, J S Cubert, April 26, 1977: US04020332 (136 worldwide citation)

A general purpose interpolator-decimator circuit for increasing or decreasing the sampling rate of a digital signal by a factor L/M, where L and M are integers, is disclosed. The circuit includes means for determining each output sample by multiplying a sequence of previous input samples by a set of ...

Frank Manning: Programmable arrays. Rines and Rines Shapiro and Shapiro, April 26, 1977: US04020469 (130 worldwide citation)

Iterative units of an array are programmed for selected processing functions, for unit testing, and for avoidance of defective units, by loading mechanisms which permit a unit to be programmed and then to extend a loading path to an adjacent unit, so that loading paths may be established directly fr ...

David P Himmel: Apparatus and a method for storage and retrieval of image patterns. Recognition Equipment Incorporated, John E Vandigriff, April 26, 1977: US04020463 (119 worldwide citation)

A line image or a line signature is optically scanned to generate digital signals for storage in an image matrix. These digital signals represent black and white cells defining the line signature or line image and are initially processed by tracing the image boundary. During the tracing a "thinning" ...

Douglas L Fox: Corrosion-resistant encasement for structural members. Edward F Levy, April 26, 1977: US04019301 (115 worldwide citation)

A protective system for concrete, wood and steel piling or other structures subject to corrosion or wear from the action of water. The system includes an encasement sleeve surrounding the piling or other structure and made of fiberglass, epoxy resin, or other inert, corrosion resistant material, and ...

John J Johnson IV: Beam suspension system. Cahill Sutton & Thomas, April 26, 1977: US04019298 (104 worldwide citation)

A dual tapered dovetail shaped mortise is formed within a joist to receive a dual tapered dovetail shaped tenon extending from a beam. Laterally oriented cavities are disposed within opposite faces of the mortise to receive correspondingly configured ridges formed integral with the mating tenon. The ...