Abstract: A miniaturized multilamp photoflash array having a plurality of flashlamps affixed to a printed circuit on the inner surface of a circuit board with a continuous strip of switching material forming a plurality of normally closed (N/C) switches coupling the flashlamps to a common conductor and a plurality of normally open (N/O) switches coupling all but one of a plurality of flashlamps to an energizing conductor.

Abstract: A miniaturized multilamp photoflash array includes an envelope with a printed circuit of spaced electrical conductors on an inner surface, a plurality of flashlamps each having a pair of electrically conductive leads and a reflector unit affixed to the envelope and having a formed member forcing the conductive leads against the printed circuit and a sonic projection sealed to the envelope intermediate the spaced electrical conductors of the printed circuit.

Abstract: A photoflash unit in the form of a multilamp photoflash array has at least one normally open (N/O) radiation-responsive switch which includes an admixture containing silver-coated metal particles.

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 flashlamp unit for individual and sequential firing of flashlamps includes a pair of flashlamps connected in an electrical circuit with a radiation-responsive N/O arc gap switch in series connection with one of said pair of flashlamps and including an arc gap having a radiation-responsive material thereover and therebetween.

Abstract: A photoflash device circuit board assembly including a dielectric substrate, switching element, and conductive member. The switching element and conductive member are pressed (e.g., die-stamped) within the substrate. The substrate is provided with a flexure means to permit it to flex during pressing such that the switching element will not be severed. A photoflash device including the circuit board assembly and a light-transmitting housing and an electrically activated flashlamp is also described.

Abstract: A photoflash unit having a plurality of flashlamps mounted 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 over a finite time interval. The switches are prepared from compositions comprising admixtures of silver carbonate and/or silver oxide, silver-coated glass beads and a binder; the admixtures may also include electrically non-conductive particulate solids, such as titanium dioxide, and/or silver-coated metal beads.

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 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 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 which includes a printed circuit board and a plurality of electrically-activated flashlamps. Each lamp includes a pair of lead-in wires each of which includes a looped portion for being frictionally inserted within an opening in the board to secure the lamp thereto. The looped portions may also be utilized to effect contact with the board's lamp-firing circuitry or separate portions of the wires may be crimped, bent, etc. to provide said contact.

Abstract: A photoflash unit comprising a plurality of high-voltage type flashlamps mounted on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high-voltage firing pulses applied thereto. One lead-in wire of each of the flashlamps is connected to a common circuit conductor. An electrically conductive reflector unit is positioned between the lamps and the circuit board. The reflector unit is grounded to the common circuit conductor by means of a dried paste of conductive material disposed at the interface between the reflector and common conductor. In this manner, the reflector unit functions as an electrostatic shield for the circuitry.

Abstract: In a compact multilamp photoflash arrangement for providing more lamps in a given volume, a reliable sequencing circuit of normally open and normally closed switches is provided by employing a series-parallel combination of the normally open switches which minimizes resistance buildup and circuit discontinuity problems.

Abstract: A photoflash lamp array comprising a plurality of high-voltage type flashlamps mounted on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high-voltage firing pulses applied thereto. The circuit board has an integral connector tab with a pair of terminals on one side connected to the igniting circuitry. Electrostatic protection is provided by a conductive shield of planar configuration disposed parallel to the circuit board and spaced therefrom on the side opposite that on which the lamps are disposed. The conductive shield is shaped with a portion thereof extending toward the end of the connector tab on the side opposite from the terminals to provide a discharge path for electrostatic charges in proximity to the tab. Preferably the shield extension is narrower than the tab and fits within a slotted recess therein between the tab and a back housing member.

Abstract: A photoflash lamp array comprising a plurality of high voltage type flashlamps mounted on a printed circuit board containing circuitry for sequentially igniting the flashlamps in response to successive high voltage firing pulses applied thereto. A plurality of reflectors respectively associated with the flashlamps are disposed between the lamps and circuit board, with each reflector having an aperture in alignment with a corresponding aperture in the circuit board. Connected in series with each but the last lamp of the array is a radiant-energy-activated disconnect switch comprising a strip of electrically conductive heat shrinkable, polymeric material which is attached at both ends to the circuit board so as to bridge a respective one of the apertures therein.