摘要:
There is disclosed herein a self-shearing stencil for use in applying solder paste or other bonding material atop a printed circuit board (PCB) in a predefined pattern. The stencil 50 has a top surface 12, a bottom surface 14, a first surface cavity 16 in the top surface, and a second surface cavity 18 in the bottom surface proximate the first surface. The cavities 16/18 overlap in a predefined manner so as to be in open communication with each other. When the stencil is placed on the PCB, the cavities are filled with solder paste and the PCB is then lowered away from the stencil, whereupon a bottom ledge 26 (defined by the stencil material underneath the first cavity) shears off the solder paste in the first cavity from the paste in the second cavity.
摘要:
Flatwire assembly having a number of conductive elements or traces position on the substrate of the flatwire. In order to protect the conductive element from environmental hazards such as moisture and chemicals, a sealing film is provided that encapsulates the conductive elements. The sealing film has a polymer layer and an adhesive layer. The polymer layer prevents vertical diffusion of moisture into the conductive elements and the adhesive layer prevents later diffusion of moisture. The sealing film is larger than the conductive elements such that it completely encapsulates the conductive elements.
摘要:
A multi-layer circuit board having apertures that are selectively and electrically isolated from electrically grounded member and further having selectively formed air bridges and/or crossover members which are structurally supported by a polymeric material. Each of the apertures selectively receives an electrically conductive material.
摘要:
A method for making multi-layer electronic circuit boards 64 having “blind” type apertures 28, 30 which may be selectively and electrically grounded and further having selectively formed air bridges and/or crossover circuits 45, 46.
摘要:
A method for making a multi-layer circuit board 116 having apertures 96, 98 which may be selectively and electrically isolated from electrically grounded member 46 and further having selectively formed air bridges and/or crossover members 104 which are structurally supported by material 112. Each of the apertures 96, 98 selectively receives electrically conductive material 114.
摘要:
Positioning of sensitive electronics near the engine block is accomplished through the use of a heat shield providing for removal or diversion of transmitted heat from the block to the electronics through the use of a self-contained or externally circulated coolant fluid. Unlike conventional coolant channels in an engine block, the heat shield is not intended to cool the engine block and thus may be more compact insofar as it deals with lesser heat flux.
摘要:
Disclosed herein is a method and apparatus for splicing flexible circuit boards, particularly those having one or more flexible strip extensions with conductor runs. The splice clamp of the present invention has two hinged plates that clamp over unconnected ends of two flexible circuit board segments. The splice clamp includes alignment guides for aligning the segments in the clamp so that one or more jumpers contact and provide an electrical bridge between the conductors of the segments when the plates are clamped together. The jumpers contact conductive pads of larger size than the conductor runs to ensure electrical coupling between the flexible circuit board segments. The jumpers may have pointed tips that cut through insulation. The clamp includes flexible clasps on one plate that engage with catch surfaces on the other plate to lock the flexible circuit board segments spliced together.
摘要:
A circuit board includes a substantially non-conductive substrate and first and second rigid sheets. The first sheet forms a grid pattern substantially encapsulated by the substrate, and a portion of the first sheet extends beyond a boundary of the substrate to form a first interconnection terminal. The second sheet is also substantially encapsulated by the substrate and has a portion which extends beyond the boundary of the substrate to form a second interconnection terminal. The second sheet acts as an electromagnetic interference shield, and also has a coefficient of thermal expansion less than a coefficient of thermal expansion of the substrate.
摘要:
There is disclosed herein a printed circuit board onto which an electronic component heat spreader may be soldered by laser soldering, one embodiment of which comprises: a dielectric substrate 10 having a top surface 11 on which a footprint perimeter P of the component heat spreader is defined, and two or more heat spreader mounting pads 20 arranged on the substrate top surface 12. Each mounting pad 20 comprises a first portion 21 arranged on the substrate surface 12 outside of the footprint perimeter P, and a second portion 22 arranged on the substrate surface 12 inside of the footprint perimeter P contiguous with the first portion 21.
摘要:
An apparatus is provided for both conveying air and for housing electronic devices in a vehicle. The apparatus comprises a molded ventilation duct with a parallel housing secured to the duct for housing electronic devices. The housing is molded integrally with the duct and metallized with electronic circuitry and devices. This design improves packaging efficiency underneath the vehicle instrument panel.