Abstract: The present invention is directed to a method and apparatus for exposing photosensitive material to form high quality continuous tone and/or color images thereon. The preferred apparatus includes an imaging head comprised of square pixel image generators, e.g., fiber optic tubes mounted to form a rectangular array. The pixel image generators are inclined at an angle of 45 degrees to the scan direction. As the print head scans, each fiber optic tube can expose a pixel image onto the photosensitive material. The exposure levels of the pixel images are preferably specified in a digital file representing an image to be printed. As a result of being inclined at 45 degrees, the pixel images exposed onto the photosensitive material are diamond shaped. Each pixel image overlaps its neighbor by substantially 50% of the center to center distance between pixel images.

Abstract: In a thermal spray process, a wire is fed into a flame-jet to heat said wire to the melting point, atomize and projected high velocity the droplets so formed against a surface to buildup a coating of material on the surface. The wire is fed into the flame by aligning the cast-plane of the wire with the flame-jet by using a tubular member formed into a circular shape to provide sufficient length to guide wire and to provide the necessary twist amount to the wire to align the cast-plane with the axis of the flame-jet.

Abstract: A surgical implant suitable for treatment of hernias is provided. The implant comprises a mesh having a residual maximum mass density of 50 g/m3. The mesh comprises strands forming spaces and the strands comprise filaments forming pores. The spaces and pores are sized to minimise foreign body mass for implantation and to encourage integration of the implant. The mesh may be delivered using Dual Phase Technology™ for ease of handling, cutting and placement. The Dual Phase Technology™ may include encapsulation or coating with hydrogel.

Abstract: The present invention is directed to a method and apparatus for exposing photosensitive material to form high quality continuous tone and/or color images thereon. The preferred apparatus includes an imaging head comprised of a plurality of red light sources, a plurality of green light sources, and a plurality of blue light sources. The light produced by said green light sources is passed through a first filter having a narrow spectral transmission characteristic in the green spectral range. Similarly, the light produced by said blue light sources is passed through a second filter having a narrow spectral transmission characteristic in the blue spectral range.

Abstract: The present invention provides a surgical implant and method for supporting the urethra (118), the implant comprising: a suburethral support (10) suspended between two soft tissue anchors (30) that do not penetrate the lower abdominal wall and are attached at either side of the suburethral support (10). The soft tissue anchors (30) retain each anchor in soft tissue, suspending each side of the suburethral support (10). The suburethral support (10) passes under the urethra (118) to support the urethra (118). The implant has uses including treating urinary incontinence and uterovaginal prolapse.

Abstract: A method and apparatus for normalizing the output of multiple light sources used to expose a photosensitive material to print high quality continuous tone and/or color images. Each of the multiple light sources is driven by a different signal weighted to cause all of the light sources to output light of intensity appropriate to produce a uniform image density over a wide range of image densities. In a preferred embodiment, each light source is driven by a different digital-to-analog converter (DAC) and/or timer circuit. A control processor supplies a multibit correction value tog each DAC and/or timer circuit to supply a drive signal to its associated light source weighted to cause all of the light sources to output light of substantially uniform intensity at a certain intensity level.

Abstract: A supersonic flame jet device includes a body having an entry portion of relatively small cross-sectional area, an expanding supersonic nozzle section and a cylindrical duct of extended length connected in series with each other. In using the device, an oxidant at high pressure is introduced into the entry passage wherein the flow is increased to sonic velocity. The sonic velocity flow of oxidant is then introduced into the passage of expanding cross-section in the direction of the gas flow while introducing a fuel to be burned into the flow of the oxidant. The velocity of flow of the oxidant or the oxidant and the fuel is then increased to supersonic velocity prior to entry into the extended duct of constant cross-sectional area where a shock is produced to stabilize flame reactions along the extended duct length whereby a supersonic flame jet will exit the extended duct.

Abstract: A plasma jet or a supersonic flame jet emanating from an internal burner combusting compressed air and fuel is applied to a solid rod coaxially within the flame or plasma jet to heat, atomize and project a spray of initially liquid droplets of the rod material separating from the tip of the rod in the direction of a workpiece for impact against a workpiece surface for solidification to form a coating thereon. The process involves the control of the transit of the initially liquid droplets from the tip of the rod over the path of travel to the surface of the workpiece to ensure that at the moment of impact against the surface of the workpiece the rod material particles are least partially solid. The stand-off distance may be set to ensure that the initially liquid droplets pass through an upstream liquid region and a contiguous downstream transit region to effect the partial solidification of the molten liquid droplets prior to impact.

Abstract: A flame spray device of the internal burner type has a fuel and oxidizer mixture combusted within a combustion chamber feeding products of combustion to a discharge nozzle passage of reduced inner diameter. An axially aligned metal piece injector has a centrally disposed injection bore hole positioned upstream of the combustion chamber and is provided with particles which are fed through the centrally disposed injection bore hole with the injection bore hole opening near the entrance of the nozzle passage. The metal piece terminates in a cone-shaped section with a reduced diameter end proximate to the entrance to the nozzle passage. A knife-edge terminal face is thereby produced intersecting the injector bore hole to minimize turbulence and rotation of the stream of carrier gas containing the powder exiting the injector metal piece injection hole.

Abstract: A high temperature flame spray or plasma effects thermal spray impact of molten materials against a target area of a surface to be built up, which molten particles, when cooled, are in tension, and an impact fusion internal burner device producing a supersonic jet stream impacts thermal spray heated solid particles against the surface in the target area such that the high velocity of the individual solid particles are impact fused, causing compressive stresses to be set up in the fused solid particles. The individual particle tensile and compressive stresses cancel one another to form an overall essentially stress-free coating. The flame spray molten particles and the flame spray heated solid particles may impact the surface concurrently at a same impact point.

Abstract: An internal burner combusting an oxy-fuel or air-fuel mixture, or a plasma heat source providing a supersonic flame jet which when expanded to atmospheric or lower pressure is characterized by a static temperature well above the melting point of a material in particle form being sprayed by the flame jet and the step of reducing the flame jet temperature after reaching supersonic velocity to a temperature below the melting point of the material prior to feeding of the material particles into the flame jet. The jet temperature reduction may be effected by injecting directly into the flame jet stream an amount of liquid or gas fluid which will reduce the flame jet temperature by the required amount. Alternatively, the supersonic flame jet may be passed through a concentric heat exchanger bearing a coolant medium such as water to absorb the necessary amount of heat from the flame jet to reduce the flame jet temperature to below the melting point of the material.

Abstract: A fuel and oxygen mixture is combusted within an internal burner combustion chamber at temperatures ranging from 250 psi to 1,000 psi. The products of combustion are directed through a restricting nozzle throat and a supersonic expansion nozzle section into an elongated duct formed by an extended nozzle length. Abrasive particles are introduced into the supersonic flow jet stream near the entrance to the elongated duct to accelerate the particles to extreme velocity, with the combustion pressure maintained sufficiently high to limit the jet stream temperature to that which is insufficient throughout the elongated duct to raise the particle temperatures to the plastic point of the particle material. The temperature of the supersonic gas flow through the elongated duct may be reduced by the introduction of a cooling flow into the jet stream beyond the flow-restricting nozzle throat. The cooling flow may be a flow of water or other liquid coolant or cool compressed air.

Abstract: A method of operation of a plasma torch, an internal burner or the like to produce a hot gas jet stream directed toward a workpiece to be coated by operating the plasma torch or internal burner at high pressure while feeding a powdered material to the stream to be heated by the stream and projected at high velocity onto a workpiece surface.

Abstract: An internal burner for producing a subsonic air-fuel flame jet capable of flame finishing granite of similar hard stone has a body forming a closed combustion chamber fed with an essentially stoichiometric flow of compressed air and fuel such that upon ignition and combustion of the reactants, there is produced at pressures in excess of 30 psig hot products of combustion. A first nozzle within the body of relatively small diameter d.sub.1 at the exit end of the combustion chamber expands the products to supersonic velocity. A duct of sufficiently large diameter within the body downstream of the first nozzle and open thereto converts a jet of hot gases to subsonic velocity by shock action prior to discharging the hot gas products of combustion. A second nozzle having a large diameter d.sub.2 in excess of the diameter d.sub.1 of the first nozzle and open to the duct at the end opposite the first nozzle produces a subsonic flame jet to be directed against the rock surface.

Abstract: A compressed air with or without water droplets in mist form and additional pure oxygen is passed over the radially exterior hot surfaces of an expansion nozzle having a L/D ratio of at least 3-to-1 and preferably surrounded by thermal insulation to enhance regenerative heat exchange between the expansion nozzle and the compressed air stream, as well as regenerative heat exchange with the exterior of a combustion chamber wall of an internal burner, also surrounded by thermal insulation prior to the compressed air entering the combustion chamber for ignition with a mixture of fuel. This permits large operating economics to be realized, reducing the need for expensive pure oxygen as the oxidant and permits the elimination of forced cooling by confined water flow for such internal burners.

Abstract: In a combustion of plasma flame spray apparatus a tightly-packed array of individual wires or rods is fed into and through the plasma flame to heat, atomize and project against a surface to build up a coating thereon. The individual wires may be arranged as parallel strands or twisted together to form a cable. The wires are of circular diameters, and the twisted array of wires may be held together by a cement which is consumed when passing through the flame region. The cement may constitute a pyrophoric mixture such as a sheath surrounding the array of wires and consist of a stoichiometric mixture of two reactive metals including nickel and aluminum which react to form a nickel-aluminide.

Abstract: A surface discontinuity is formed along an anode nozzle bore sufficiently upstream of a nozzle exit orifice and of a sufficient size to cause an arc between an electrically conductive end wall of a plamsa-arc torch anode nozzle passage and a coaxial cathode coaxially mounted by an opposite end wall of the torch cylindrical casing having a gas under pressure and at an established vortex flow to pass through the nozzle passage. A boundary layer of the vortex flow of gas along the anode bore wall provides a path for the arc to pass directly to the anode nozzle passage at or just downstream of the disturbance zone provided by the nozzle passage wall surface discontinuity. A counterbore may extend along a portion of the nozzle axis from the nozzle exit axially inwardly to form a radial shoulder with the main bore of the anode nozzle and define the discontinuity.

Abstract: A surface discontinuity is formed along an anode nozzle bore sufficiently upstream of a nozzle exit orifice and of a sufficient size to cause an arc between an electrically conductive end wall of a plasma-arc torch anode nozzle passage and a coaxial cathode coaxially mounted by an opposite end wall of the torch cylindrical casing having a gas under pressure and at an established vortex flow to pass through the nozzle passage. A boundary layer of the vortex flow of gas along the anode bore wall provides a path for the arc to pass directly to the anode nozzle passage at or just downstream of the disturbance zone provided by the nozzle passage wall surface discontinuity. A counterbore may extend along a portion of the nozzle axis from the nozzle exit axially inwardly to form a radial shoulder with the main bore of the anode nozzle and define the discontinuity.

Abstract: A flame-spray duct defined by the portion of a bore passing through a flame-spray body at the outlet end thereof having a duct L/D ratio of at least 5-to-1 is associated with elements within the flame-spray body which assure nearly uniform flow of reactant oxidant and fuel mixture at the point of introduction of the particulate material within the duct to eliminate the formation of eddies and recirculation regions thereby preventing uninterrupted even flow of the particulate material from the point of introduction into the duct to the exit from the duct resulting in even heating of the particulate material and where the material is capable of melting, the adherence of molten particulate material on the wall of the duct. The elements within the flame-spray body may take the form of a relatively small diameter oxidizer inlet bore leading to a diverging conical diffuser leading to and emerging with a larger diameter bore section defining the flame-spray duct.

Abstract: A high voltage, high current is applied between a cathode electrode and a conductive body forming a spray nozzle and acting as a second anode electrode aligned with the first electrode and being spaced therefrom. A vortex flow of plasma-producing gas is established within a cylindrical body carrying said electrode to create a low pressure core of gas flow extending through the anode passage to establish an extended ionized arc column throughout the anode passage with the rate of gas flow adjusted and the arc current correlated to the anode nozzle passage diameter to produce a supersonic extended ionized arc column which extends beyond the end of the nozzle by a distance which is approximately four times the nozzle passage diameter. Preferably the material to be sprayed is introduced into the extended ionized arc column beyond the end of the nozzle to maximize the spray rate without undesirably overheating the spray material.