Abstract: An improved primer material for use in a high-voltage photoflash lamp is provided. The primer material includes electrically insulating beads which have been coated with a friction-reducing material. The primer also includes an oxidizing agent, and a binder, and a combustible metal powder, part of the combustible metal powder being in larger particle form. A high-voltage photoflash lamp including the improved primer material of the present invention is also disclosed.

Abstract: A high-voltage photoflash lamp is provided wherein the lead-in wires are electrically insulated from the metallic shreds therein by including electrically insulating beads in the primer material. The primer also includes combustible metal powder, an oxidizing agent, and a binder, wherein at least part of the combustible metal powder in the primer is in large particle form.

Abstract: A rapid-start fluorescent lamp includes a circuit breaker having a sealed glass bottle, a pair of electrical conductors sealed therein and passing therethrough and a thermally sensitive bimetal switch within the glass bottle with the bimetal switch having a pair of leg portions of unequal length.

Abstract: A high-voltage photoflash lamp is provided wherein the primer material is electrically insulated from the metallic shreds therein by an adherent layer of hollow electrically insulating beads. The layer of hollow beads is contiguous to the surface of the primer material within the lamp envelope.

Abstract: A rapid-start fluorescent lamp includes a pair of spaced electrodes within an envelope with one electrical lead connected to an electrode and the other lead coupled to the electrode by a thermally-sensitive bi-metal strip whereby one end of the bi-metal and one end of a conductor are formed to provide a straight member within a U-shaped member such that the straight U-shaped members are in electrical contact at temperatures above and below a given range of temperatures and electrically disconnected at the given range of temperatures.

Abstract: A rapid-start fluorescent lamp includes a pair of spaced electrodes within an envelope having a fill gas and a phosphor-covered inner wall surface with a circuit breaker having a glass bulb with a wall thickness in the range of about 0.016 to 0.018 inch positioned within the fluorescent lamp.

Abstract: A photoflash lamp has an envelope containing a filamentary combustible material in a combustion-supporting atmosphere and is positioned adjacent an ignition means having a pair of electrical conductors sealed into one end of the envelope and bent to form loops within the envelope whereon a covering of primer material is disposed.

Abstract: A high-voltage type photoflash lamp filled with a filamentary combustible material and oxygen and having an ignition structure including a pair of spaced-apart lead-in wires sealed in one end of the glass envelope of the lamp and encapsulated within an interior protruding portion of the envelope glass. The termination of each of the lead-in wires within the envelope is bare of sealing glass and substantially flush with the surrounding glass surface, and a coating of primer material about the inner end of the protruding portion of glass within the envelope covers and bridges the bare terminations of the lead-in wires.

Abstract: A high-voltage type photoflash lamp filled with a filamentary combustible material and oxygen and having an ignition structure including a pair of spaced-apart lead-in wires sealed in one end of the glass envelope of the lamp and encapsulated within an interior protruding portion of the envelope glass. The termination of each of the lead-in wires within the envelope is bare of sealing glass and substantially flush with the surrounding glass surface, and a coating of primer material about the inner end of the protruding portion of glass within the envelope covers and bridges the bare terminations of the lead-in wires.

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: A multilamp photoflash unit including an elongated plastic housing having a longitudinal channel therein. Within the channel is positioned a thin, flat circuit board to which are connected several (e.g. six) flashlamps arranged in a linear array. The lamps are divided into two opposing pluralities such that those in the plurality being fired are inverted during firing.

Abstract: A compact photoflash unit comprising a plurality of flashlamps having lead-in wires connected to a circuit board containing thereon radiation-sensitive switching circuitry for sequentially flashing the lamps. Electrically conductive reflector panels are positioned between the lamps and the circuit board, and a sheet of electrically insulating material is interposed between the reflectors and the circuit board to prevent shorting of the circuitry on the circuit board by the conductive reflector. The insulating sheet, which may be of transparent plastic, is provided with T-shaped tabs which interlock with slots in the circuit board to secure the aligned position of the insulating sheet thereon. In assembling the photoflash unit, the insulating sheet is placed on the circuit board prior to mounting the lamps, and the T-shaped tabs of the sheet are inserted in the circuit board slots to secure the aligned location of holes in the insulating sheet with lamp-mounting eyelets in the circuit board.

Abstract: A high-voltage type photoflash lamp filled with a filamentary combustible material and oxygen and having an ignition structure comprising a pair of spaced apart lead-in wires bridged at their inner ends by a mass of primer material. An insulating sleeve encloses one of the wires, with the end of that wire extending beyond the open end of the sleeve. Formed at an angle from the other lead-in wire is a terminating portion which overlies and is spaced from the open end of the sleeve to provide a predetermined gap between the terminating portion and the end of the sleeved wire. The primer material is disposed to cover the open end of the sleeve and bridge the gap.

Abstract: A high-voltage type photoflash lamp filled with a filamentary combustible material and oxygen and having a beadless ignition structure comprising a pair of spaced apart lead-in wires with spherically shaped terminations, a glass frit coating over the lead-in wires with scraped-off portions exposing the bare metal of the wire adjacent each termination, and a coating of primer material over the frit-coated terminations and bared portions of the wires. The primer may bridge the wire terminations or comprise separate spaced apart coatings on the respective terminations, with the filamentary combustible being in contact with both terminations to provide a conducting path therebetween. The frit coating is thick enough to prevent preignition short circuits.

Abstract: A photoflash lamp containing a readily ignitable, hydrogen-containing substance, such as shredded paper or a spot of sucrose, to controllably induce bursting of the lamp upon ignition for purposes of testing the relative strength and reliability of lamp containment systems, including the envelope, envelope coatings and flash unit enclosures.

Abstract: A photoflash lamp having an envelope comprised of a lead-containing glass having a low coefficient of thermal expansion and a pair of filament-supporting lead-in wires secured to the glass envelope by means of a graded seal having a lead-free intermediate expansion glass disposed between the envelope and lead-in wires. The lead-in wires are composed of an iron-nickel-cobalt alloy. The intermediate expansion glass may be in the form of a bead having its midportion between the lead-in wires stretched to protrude toward the filament to prevent post-ignition short circuits.