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 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 photoflash unit comprising a plurality of 2n flashlamps attached to a printed circuit board and disposed in a linear array with the longitudinal axes of respective lamps aligned in parallel. Circuit patterns on the circuit board include a plurality of n selective terminal means, each associated with a respective pair of the lamps and connected to one lead-in wire of each of the lamps of the associated pair, and a common terminal associated with all of the 2n lamps but directly connected to the other lead-in wire of one lamp of each pair. The circuit board has a substantially rectangular portion with n spaced apart extensions projecting vertically from a longer side thereof, the extensions being located behind alternate lamps of the linear array. Each extension contains portions of the circuit patterns spaced apart to form predetermined gaps, and a mass of switch material is disposed on each extension to bridge the gap between circuit patterns to thereby provide a solid state radiation switch on each extension behind and adjacent to a respective lamp for receiving radiant energy emitted by that lamp. In this manner, a respective normally open switch on each circuit board extension is coupled between the common terminal and a lead-in wire of the other lamp of each pair of lamps, so that the n normally open switches are coupled between the common circuit lead-in wire of associated pairs of the 2n lamps.
Abstract:
Improved fuse elements used with the circuit board to provide more reliable sequential firing in a flash lamp array. The circuit board includes a lamp firing circuitry along with radiation switches connected in said circuitry and more reliable fuse elements cooperate with said radiation switches in the circuit operation. The improved fuse elements are constructed as an integral part of the lamp firing circuit pattern deposited on the circuit board at circuit locations wherein the underlying circuit board substrate has a thickness less than the substrate thickness elsewhere to enhance melting or thermal decomposition of the circuit board substrate.
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. The circuitry further includes a plurality of radiant-energy-activated connect switches disposed on the circuit board in alignment with respective reflector apertures and each comprising a mass of high resistance material convertible to a conductive state upon being activated by radiant-energy. The high resistance material is also disposed on and about each of the ends of the disconnect switch strips, whereby the high resistance material provides mechanical protection for the disconnect switch ends and electrical insulation between the circuitry connected to and located adjacent these switch ends and the conductive reflectors and/or proximate circuitry. In making the circuit board, first the disconnect switch strips are mounted on a nonconductive substrate; then conductive ink is printed on the substrate in a desired circuit pattern and cured; then a paste of the high resistance material is printed on the substrate in a desired pattern of patches to provide both the connect switches and the areas of protection and insulation.
Abstract:
A photoflash unit is designed to have a plurality of lamps fired individually and in sequence and includes a plurality of switching devices capable of being easily activated by radiant energy generated during flashing of the lamps. Initially, the switches have a high resistance ("off" condition) and after being activated by radiation, they undergo a chemical change to a conductive state ("on" condition). The switches are prepared from compositions which impart improved shelf life to the switches under conditions of high relative humidity.
Abstract:
The reliability of radiation switches is improved in accordance with this invention by mechanically modifying the contact members of the switch structure to reduce the heat sinking effectiveness of the switch contact members.
Abstract:
A method of heating selected areas of an element having at least one portion that is to remain relatively unheated, in which radiant energy from a radiant energy source is focused upon the element by suitable reflector means, and a masking member is positioned over the protected portion to serve the dual functions of deflecting radiant energy away from the protected portion and directing the radiant energy which would otherwise strike the masked portion to impinge upon the selected areas and thereby increase the energy density upon the selected areas. The above method may be utilized for either heating or tinning the leads of electronic devices, or soldering the leads of electronic devices to associated terminals. In order that the soldering operation be performed rapidly and reliably, the solder may be prepared in granulated form suspended in a binder, and spread upon the selected areas to be tinned or soldered, and is exposed to the radiant energy where the solder paste absorbs significantly more radiant energy than conventional solder to form a good solder joint more rapidly than through the use of conventional solder and conventional soldering techniques.
Abstract:
A resin substrate includes an insulating base material including opposing first and second main surfaces, at least one of which is parallel or substantially parallel to each of an X-axis direction and a Y-axis direction. The insulating base material is divided into first and second sections arranged in the X-axis direction. The first section includes, when evenly divided into three in a Z-axis direction, a first region closest to the first main surface, a second region closest to the second main surface, and a third region between the first region and the second region. A degree of resin molecular orientation in the first region in the Y-axis direction is greater than a degree of resin molecular orientation in the second section of the insulating base material in the Y-axis direction.