Abstract: A photoflash lamp includes a glass envelope having a pair of electrical conductors forming a recessed seal with a primer material bridging the electrical conductors and extending into the recessed seal to contact the electrical conductors. Also, a process for fabricating a photoflash lamp is provided wherein the electrical conductors and glass envelope are moved with respect to one another to provide a recess in the envelope adjacent the electrical conductors. A primer material in liquid form is bridged across the electrical conductors and subjected to a vacuum to insure removal of any gap between the electrical conductors and the primer material.

Abstract: A circuit board assembly wherein the assembly includes a dielectric substrate, at least one radiation sensitive switch, and at least one conductive member in electrical contact with the switch. Portions of the switch and the conductive member are die-stamped into the dielectric substrate to achieve the contact without severing the switch material.

Abstract: A photoflash device circuit board assembly including a dielectric substrate and at least one switching element and conductor die-stamped therein. To assure that the delicate switch is not severed by the die's cutting edge during die-stamping, a relief means (e.g., slot) is provided within the substrate so that a segment of the switch can be aligned therewith. As an alternative, it is taught to provide stepped portions within the die's cutting edge to align with preselected portions of the switch and thus prevent total severance thereof.

Abstract: A self-sequencing multilamp photoflash array responsive to a low voltage source includes radiation-responsive switches having a pair of electrical conductors spaced by a switch paste comprising a heat sensitive silver compound, a powdered metal in stoichiometric excess and an organic binder. The array has a flashlamp coupled to a pair of electrical conductors and a plurality of series connected flashlamps and radiant-responsive switches connected in parallel to the electrical conductors with each switch responsive to a previously energized flashlamp. Also, a process is provided for fabricating the switches and the array.

Abstract: A high intensity discharge device includes a reactive element which will oxidize and grow dimensionally to open the lamp circuitry in the event oxygen leaks into the outer envelope of the lamp.

Abstract: A method of making a hermetically-sealed pyrotechnic cap is described which includes a plastic (e.g. polyethylene) container and a quantity of pyrotechnic mixture therein. Closure of the container is achieved by heat-sealing an end thereof.

Abstract: An improved pyrotechnic cap which includes a plastic container having a quantity of pyrotechnic composition hermetically sealed therein. The cap is capable of being ignited by the radiant energy from an adjacent flashlamp to provide an audible signal of high intensity (e.g. 158 to 164 decibels at 25 centimeters). The improvement constitutes providing the composition with a quantity of desensitizing material (e.g. powdered polyethylene) which significantly decreases the cap's sensitivity to ignition by mechanical impact or crushing.

Abstract: A high-voltage type photoflash lamp having an ignition structure including an improved primer material for the reliable ignition of filamentary combustible material distributed within the oxygen-filled envelope of the lamp. The primer material comprises a particulate fuel such as zirconium powder, a binding agent such as nitrocellulose, and an additive of finely divided inert material which is insoluble and nonconductive and has a particle size of less than about five microns diameter.

Abstract: Venting apertures for multi-lamp photoflash units having a plurality of spaced flashlamp receiving cavities are provided intermediate the cavities whereby no direct path for fragments from a flashlamp within a cavity to the exterior of the unit is provided. In another aspect, a reflector unit having venting apertures aligned with the venting apertures of the above-described photoflash unit is enclosed with the photoflash unit with no direct path for projectiles from the photoflash lamp to the exterior of the photoflash unit.

Abstract: A process for applying a protective light-transmitting coating to a photoflash lamp comprising the steps of applying the protective coating to the lamp and curing the applied coating by exposure thereof to radiant energy and characterized by the improvement wherein the layer of coating applied to some portions of the photoflash lamp is thicker than the layer of coating applied to other portions of the photoflash lamp.

Abstract: A photoflash unit having a plurality of flashlamps mounted in a planar array on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive firing pulses applied thereto. The circuitry includes a plurality of solid state switches capable of being activated by radiant energy generated during flashing of lamps located adjacent to respective switches. Initially, each of the switches has a resistance sufficiently high to provide an open circuit to the applied firing pulses, and after being activated by radiation, the switch undergoes chemical conversion to a conductive state. The switches are prepared from compositions which include a selected proportion of silver-coated glass beads to consistently assure a predetermined low resistance after conversion and maintenance of good adherence and electrical contact with the printed circuit board circuitry.

Abstract: A photoflash unit comprising a horizontal linear array of photoflash lamp enclosed within a one-piece housing member having a light-transmitting front portion folded-over a back portion containing a plurality of lamp-receiving cavities in which respective lamps are disposed. The housing is a formed sheet of plastic film having a linear fold disposed horizontally along the top of the array of cavities. A pair of lead-in wires from each of the lamps are connected to conductive circuit patterns on one side of a printed circuit board sandwiched between a set of tabs which run along the bottom of the front and back portions of the housing. The housing tabs are secured together and to the circuit board by a plurality of staples symmetrically disposed along the tabs.

Abstract: A photoflash unit comprising a horizontal linear array of flashlamps enclosed within a one-piece housing member having a light-transmitting front portion folded over a back portion containing a plurality of lamp-receiving cavities in which respective lamps are disposed. A printed circuit board is joined to the housing member, and a pair of lead-in wires from each of the lamps are connected to conductive circuit patterns disposed solely on one side of the circuit board. The circuit patterns include a plurality of connector terminals which are located adjacent one another on a flat tab which projects from one edge of the circuit board for insertion into the receiving socket of a firing pulse source. The tab contains a plurality of symmetrically disposed apertures or recesses which render the tab releasably engageable by socket means independent of firing pulse contacts for securely retaining the unit in the socket.

Abstract: A circuit board assembly and method of making wherein the assembly includes a dielectric substrate, at least one radiation sensitive switch, and at least one conductive member in electrical contact with the switch. Portions of the switch and the conductive member are die-stamped into the dielectric substrate to achieve the contact without serving the switch material.

Abstract: A photoflash unit comprising a horizontal linear array of flashlamps enclosed within a one-piece housing member having a light-transmitting front portion folded over a back portion containing a plurality of lamp-receiving cavities in which respective lamps are disposed. The housing is a formed sheet of plastic film having a linear fold disposed horizontally along the top of the array of cavities, which are selectively aluminized to provide a reflective coating on the cavity surfaces. A pair of lead-in wires from each of the lamps are connected to conductive circuit patterns on one side of a printed circuit board sandwiched between a set of tabs which run along the bottom of the front and back portions of the housing and are secured together.

Abstract: A photoflash device circuit board assembly including a dielectric substrate and at least one switching element and conductor die-stamped therein. To assure that the delicate switch is not severed by the die's cutting edge during die-stamping, a relief means (e.g., slot) is provided within the substrate so that a segment of the switch can be aligned therewith. As an alternative, it is taught to provide stepped portions within the die's cutting edge to align with preselected portions of the switch and thus prevent total severance thereof.

Abstract: A photoflash unit having a plurality of high voltage type flashlamps mounted in a planar array on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high voltage firing pulses applied thereto. The circuitry includes a plurality of solid state switches capable of being easily activated by radiant energy generated during flashing of lamps located adjacent to respective switches. Initially, the switches have a high resistance, and after being activated by radiation, they undergo chemical conversion to a conductive state. The switches are prepared from compositions which include a comparatively large proportion of nonconductive inert particulate solids to improve switch functioning.

Abstract: An improved photoflash unit comprising a circuit board with lamp-firing circuitry thereon, a plurality (e.g., ten) of electrically activated photoflash lamps, and a reflector located between the lamps and circuitry. The lamp-firing circuitry includes at least one switch which is activated by radiant energy emitted from an adjacent photoflash lamp. The improvement comprises providing at least one longitudinal opening (slot) within a cavity portion of the reflector between the activating lamp and switch, and surrounding the opening with a transparent, non-conductive region to thereby assure consistent switch activation by substantially eliminating arcing between the reflector and circuitry.

Abstract: A photoflash unit comprising a linear array of flashlamps mounted on a printed circuit board disposed within the longitudinal channel of an elongated housing member having an enclosing cover panel of light-transmitting material. The lamp-firing circuitry includes a common circuit conductor run connected to one lead-in wire of each of the lamps. The housing member includes reflector cavities adjacent to the lamps, and a continuous coating of electrically conductive reflective material covers the surfaces of the channel and reflector cavities for providing both reflective surfaces for flashing lamps and, by virtue of a connection between the common run and conductive coating, a shield to reduce the likelihood of accidental flashing of lamps by electrostatic charges.

Abstract: A high-voltage type photoflash lamp having an ignition structure including an improved primer material for the reliable ignition of filamentary combustible material distributed within the oxygen-filled envelope of the lamp. The primer material comprises, a particulate fuel such as zirconium powder, an oxidizer salt such as potassium perchlorate, a binding agent such as nitrocellulose, a finely divided inert material such as fumed alumina, and an additive of conductive fibers for controlling breakdown voltage. A preferred additive comprises finely milled or chopped fibers of carbon or graphite.