Abstract:
A method of removing components from circuit boards includes the steps of placing in a chamber a plurality of circuit boards having components secured to the board by meltable solder; heating a liquid to a temperature above the melting point of the solder; and melting the solder that secures the components to the board by circulating the heated liquid through the chamber to envelop the boards and the components. Thereafter the liquid, with entrained solder, may be circulated through a heat exchanger and a filter.
Abstract:
A circuit board system comprises a circuit board having a base part (101) and at least one changeable part (102) furnished with at least one electrical component (103) such as a light emitting diode. The base part comprises an aperture for receiving the changeable part so that a perpendicular of the changeable part is parallel with a perpendicular of the base part. The aperture is shaped to allow the position of the changeable part to be changed with respect to the base part when the changeable part is in the aperture, and edges of the aperture and the changeable part have mutually cooperative connection portions (105, 106) which allow the changeable part to be introduced on the aperture when the changeable part is in a first position and which limit freedom of the changeable part to get away from the aperture when the changeable part is in a second position.
Abstract:
Biodegradable printed circuit boards, or PCBs, may be produced from substrate sheets that include at least one biodegradable polymer. In addition, the electrical traces used on the PCBs, may also include a biodegradable polymer incorporated with an electrically conductive material. The PCBs may be composted to degrade the PCBs, and the electrically conductive material may be reclaimed for re-use.
Abstract:
The invention is directed to an implantable insulated electrical circuit that utilizes polyparaxylylene, preferably as Parylene, a known polymer that has excellent living tissue implant characteristics, to provide for chronic implantation of conductive electrical devices, such as stimulators and sensors. The device is thin, flexible, electrically insulated, and stable after long exposure to living tissue. Layers of Parylene may be combined with layers of a polymer, such as polyimide, to yield greater design flexibility in the circuit. Multiple electrical conduction layers may be stacked in the circuit to increase packing density.
Abstract:
An electronic circuit interruption device (10) having a plurality of protection, indication and control options includes a dedicated printed circuit board (34) having electrical connection with operating circuits controlling each of the several options. Electrical connections between the operating circuits and the circuit interruption controller is made through corresponding dedicated resistors (39-46). Option selection is obtained by removal of resistors connecting with non-selected circuits on the printed circuit board.
Abstract:
A pluggable electrical connector (10) is provided having contact elements (20) with first ends (32) soldered to a daughter board (40), mid-sections (36) which are crimped and bent through ninety degrees, and second ends (34) which have a converging portion and which terminate in bifurcated conical contact portions (38) which make contact with the rims of contact-quality plated through holes (51) of a mother board (50). By causing contact between the rim and the cone surface, normal forces greater than the mating force are generated. The connector housing (30) includes self-centering funnel openings (66) adjacent the mother board for centering the converging portions (37) of the contact elements (20) therein in a nominal position and for acting as a preloading stop. The housing also includes side-wall locking tabs (72) which hold adjacent rows of contacts at identical fixing points relative to the ninety-degree bend to ensure identical spring parameters for all contact elements.
Abstract:
A rework grid array interposer with direct power is described. The interposer has a foundation layer mountable between a motherboard and a package. A heater is embedded in the foundation layer to provide local heat to reflow solder to enable at least one of attachment or detachment of the package. A connector is mounted on the foundation layer and coupled to the heater and to the package to provide a connection path directly with the power supply and not via the motherboard. One type of interposer interfaces with a package having a solderable extension. Another interposer has a plurality of heater zones embedded in the foundation layer.