Abstract: A method of sensing moisture based on propagation-delay provides absolute readings of volumetric water content in a moisture-bearing medium without calibrating the sensor or its readings for the conductivity or temperature of the medium. A fast transition is launched on a transmission line that is immersed in the medium to be measured. The amplitude of the resultant waveform is analyzed at precise, programmable time increments by using a high-speed latching comparator. Firmware in a controlling microprocessor facilitates the successive reconstruction of the significant characteristics of the returning waveform. The microprocessor analyzes these characteristics to provide an accurate determination of propagation delay and conductivity, even for severely distorted waveforms. The moisture content of the medium is derived from the propagation delay.

Abstract: A shelter for individuals or groups of people caught in the open in inclement weather especially when there is a danger of lightning. The shelter includes an elongate electrically-conductive member for supporting a canopy, the elongate electrically-conductive member being configured as a lightning conductor; an electrically-conducting floor; and a coupling member for electrically connecting the elongate electrically-conductive member to the electrically-conducting floor. The coupling member includes a flange extending laterally away from the elongate electrically-conducting member, over the electrically-conductive flooring, to provide an enlarged footprint of engagement with the electrically-conducting floor.

Abstract: A shelter for individuals or groups of people caught in the open in inclement weather especially when there is a danger of lightning. The shelter comprises an elongate electrically-conductive member for supporting a canopy, the elongate electrically-conductive member being configured as a lightning conductor; an electrically-conducting floor; and a coupling member for electrically connecting the elongate electrically-conductive member to the electrically-conducting floor. The coupling member includes a flange extending laterally away from the elongate electrically-conducting member, over the electrically-conductive flooring, to provide an enlarged footprint of engagement with the electrically-conducting floor.

Abstract: A convertible package and bowl type container (10) has two overlaying sheets joined along their side edges by side seals (13) and folded to form container sides (19), container ends (20), a generally square bottom (14). The container has an elongated openable seal along the top of the two sides. The sides are of a height of between one to two times that of the major side dimension of the bottom. The container is reconfigurable between a closed configuration with the top seal closed and an open, self standing configuration with a squared off open top.

Abstract: According to the present invention, an artificial tree is provided which includes a tree element having a central generally disc-shaped member and a plurality of generally annular rings concentric to the central disc-shaped member and to one another such that the central disc-shaped member and the rings, in the operative position, are positioned in a vertically spaced, tiered array, with the central disc-shaped member at an uppermost position such that the tiered array is configured to have a tree-shape. A plurality of connecting strips connect each tier of the array to a next adjacent tier of the array. The disc-shaped member, the concentric rings, and the connecting strips may be formed from a unitary sheet of material, and the disc-shaped member and the concentric rings may be formed by providing a plurality of discontinuous generally spiral slits in the sheet of material.

Abstract: A road vehicle is disclosed having a bumper assembly fitted to the rear end of the vehicle. The bumper assembly includes a beam extending across the rear end of the vehicle and supported by an arm from the vehicle so that the beam is displaceable from a rest position in a direction towards or beneath the vehicle in the event of contact with an obstacle.

Abstract: Containers (56) are produced from a sheet of flexible sheet material (10) having a sealable inner layer (12). The material is cut to expose the sealable inner layer when the material is folded upon itself so as to form a container having side seams (58) extending past the end walls of the container to prevent breaching and internal tabs (30) to prevent capillary leakage.

Abstract: A method and apparatus is disclosed for mounting constructing a flexible a tubular fitment (10) to a flexible container (11) and to the resulting product. The fitment is mounted upon a mandrel (24) having an extendable bearings in the form of an annular array of balls (27). The mandrel supporting the fitment is positioned within the container body (11) and the assembly positioned in heat sealing dies (33,34) having an annular channel (35) sized to receive the fitment. The dies have a groove (36) extending from the channel. The balls are then outwardly extended into the groove and the mandrel rotated to cause the balls to orbit in a circle and seal the fitment to the flexible container oven an annular protrusion (38).

Abstract: A grille (3) for use adjacent an outlet of a heating, ventilating or air conditioning system comprising a frame (15) and a plurality of blades (25) extending between opposed frame parts. Each blade (25) has a spindle (26) which is rotatably supported within opposed slots (21) formed in the opposed parts of the frame. The slots (21) are open at one end to permit the insertion of the blade spindle and the spindle is supported at the closed ends of the slots. The grille (3) further comprises means for retaining the blade spindles (26) in the slots (21). The retaining means comprise an element (30) mountable upon the frame (15) of the grille such that part of the retaining element (30) engages the blade spindles (26) when mounted upon the frame and prevents the spindles (26) from moving out of the open ends of the slots (21).

Abstract: An elongate member is coupled by a socket at one end to the aircraft surface, whilst a tip forms its other end. The electrical resistivity of the elongate member, tip and coupling is equal to or greater than 10.sup.2 ohmmeter; and are preferably molded from a high temperature thermoplastics material having an electrical resistivity equal to or greater than 10.sup.16 ohmmeter. The plastics material is selected from the group comprising polyetherimide, polyethersulphone and polyetheretherketone. The material of the tip is provided with an embedded aligned array of carbon or silicone carbide fibers while the other parts of the discharger are loaded with carbon black or coated with the same thermoplastics material loaded with 4% by weight carbon black. The adhesive used to mount the socket has an electrical resistance between 5 to 10K ohms, while that of the socket is between 5 to 10M ohms, that of the elongate member between 20 to 100M ohms, and that of the tip is between 2 to 5 ohms.

Abstract: Lightning strike protection for an aircraft or part of an aircraft is provided by mounting metal (aluminium) rods adjacent but spaced from the inner surface of the aircraft wall. The rods are provided with ball joints from which extensions through the wall stand proud of the aircraft outer surface and within the material of static dischargers. The rods are coupled to bus bar which run the length of the aircraft in turn are coupled to lightning strike dischargers (again in the form of metal rods carried on but spaced from the wall of an aircraft and having extensions which pass through the aircraft wall). The application of the lightning strike protection system to radomes, antennas, pitot tubes carbon fiber reinforced plastics structures is discussed, in the former two cases metal rods being provided to extend in the null field of a device within the radome or the antenna.

Abstract: At an outlet of a heating, ventilating or air conditioning system air passes from the ducting through a plenum chamber, a damper provided with a set of blades which are movable between open and closed positions and a diffuser which directs the air in a desired direction. The plenum chamber is provided with internal vanes which act to guide a flow of air through the chamber between its inlet and outlet. The damper defines a plurality of predetermined blade positions between the open and closed positions and a resilient finger and teeth for retaining the blades in a selected one of said predetermined positions. The damper has a frame comprising a plurality of discrete frame elements interconnected at each corner joint of the frame by a friction fit pin passing through interdigitated projections on the frame elements.

Abstract: An electronic ballast for discharge lamps comprises an open loop configuration of an impedance converter first stage and an inverter second stage linked by a limiting control stage. The impedance converter stage presents its load, passive or active, as input resistance. It draws a continuous current, through large RFI/EMI suppressing input inductors, which is switched discontinuously through a tank circuit using an energy transfer relationship based on the switch on-time and the inductance and capacitance of the tank circuit. The impedance converter stage supplies unregulated power to the inverter stage which operates stably at a fixed frequency. If an imbalance such as an overcurrent condition or an overvoltage condition develops in the system, the limiting control stage temporarily preempts the converter switching until stability is reestablished.

Abstract: A class of catalysts for the anionic copolymerization of cyclic lactams in the presence of .omega.-(N-acyllactam)polyorganosiloxanes, .alpha.,.omega.-di-(N-acyllactam)polyorganosiloxanes or star-shaped .omega.-(N-acyllactam)polyorganosiloxanes is disclosed. The catalysts successfully protect the siloxane prepolymer from harmful depolymerization reactions at elevated temperatures while anionically polymerizing the cyclic lactams via ring-opening. Diblock, triblock, multiblock and star-block copolymers, e.g., of a polyorganosiloxane and a polyamide, with advantageously high polyorganosiloxane and polyamide block molecular weights and superior heat resistance can be synthesized with the catalysts. The composition of these block copolymers, with the structure AB, ABA, and star-(BA).sub.r, r .gtoreq.3, where A=polyamide and B=polyorganosiloxane, and the process for producing them are also described.

Abstract: A class of catalysts for the anionic copolymerization of cyclic lactams in the presence of .omega.-(N-acyllactam)polyorganosiloxanes, .alpha.,.omega.-di-(N-acyllactam)polyorganosiloxanes or star-shaped .omega.-(N-acyllactam)polyorganosiloxanes is disclosed. The catalysts successfully protect the siloxane prepolymer from harmful depolymerization reactions at elevated temperatures while anionically polymerizing the cyclic lactams via ringopening. Diblock, triblock, multiblock and star-block copolymers, e.g., of a polyorganosiloxane and a polyamide, with advantageously high polyorganosiloxane and polyamide block molecular weights and superior heat resistance can be synthesized with the catalysts. The composition of these block copolymers, with the structure AB, ABA, and star-(BA).sub.r, r .gtoreq.3, where A=polyamide and B=polyorganosiloxane, and the process for producing them are also described.

Abstract: A method and apparatus for making continuous lengths of thermoplastics material fibers reinforced laminates by arranging layers of fibers reinforcement impregnated with a thermoplastics material in alignment with and between outer sheets of another material to form a stack and passing the stack through a tool having two opposing platens, one of which is movable relative to the other, and operating the tool so as to compress the stack and form a laminate. The stack is passed from entry to exit of the tool in steps, the extent of each of which is substantially less than the length of the tool such that each area of the stack is subjected to repeated compressions by the tool is passing therethrough. A recess is formed in one platen, which is adapted to receive a land formed on the other platen.

Abstract: A process for the manufacture of flexible tubes including a main body of a rubber material and a reinforcing element of a hard resin material in which the reinforcing element is embedded at least partly in the main body in a form of helical coil and adjoined thereto to form an integral body of the flexible tube. The flexible tube is manufactured by helically winding a composite web of a rubber strip and a hard resin strip adjoined to each lateral side end of the rubber strip with the web being in a plastic condition so that a lateral end portion of the resin strip in the web of each turn is made to be in contact with and adjoined to that of the preceding turn.