摘要:
A method for controlling the mass of solder applied to a printed circuit substrate (202) by a solder printer (200), whereby the mass of solder paste (114) applied to a printed circuit substrate (202) is controlled by measuring the mass of the solder paste (114) that was applied to a first printed circuit substrate. The mass data measured is then compared to a predetermined mass to produce a control signal. The mass of the solder applied to a second printed circuit substrate is controlled as a function of the control signal so that the mass of the solder applied to the second substrate more closely approaches the predetermined mass.
摘要:
A low-profile motor arrangement for accomodation in a low-volume electronic device such as a radio pager. The motor is designed to provide a vibrating action for silent alerting that does not require any additional add-on parts, but effects the required vibrator action by a designed-in unbalance in the rotating internal parts.
摘要:
A printed circuit board providing RF shielding. An electrically insulating material serves as a substrate (10) with two opposed sides. At least one side of the substrate (10) has an electrically conductive layer (12) formed in a pattern that defines a printed circuit. An insulating dielectric layer (14) covers at least a portion of the printed circuitry, leaving at least one portion (16) of the circuitry exposed. A radio frequency (RF) shielding layer (18) is formed by depositing an electrically conductive polymer on at least a portion of the insulating dielectric layer. The RF shielding layer (18) also lies over a portion of the exposed electrical circuitry (16), providing electrical connection to the electrically conductive layer (12). The RF shielding layer (18) is formed from a silverfilled polymer thick film ink and is applied by screen printing, stencilling, roller coating, spraying, or other equivalent methods.
摘要:
An electronic device (100) comprises a first substrate (102) having a first circuit pattern disposed thereon which is selectively processed to provide pretinned connection pads (108, 116, 124, 132, 140) for connection to at least one electronic component (142) and a second circuit pattern disposed on a second substrate (104). The second circuit pattern disposed on the second substrate (104) is selectively processed to further provide pretinned connection pads (110, 118, 126) for connection to the first circuit pattern, and the second substrate (104) further has relief provided within a portion thereof to position the at least one electronic component (142) with respect to the pretinned connection pads (108, 116, 124, 132, 140) on the first circuit pattern. The pretinned connection pads (108, 116, 124, 132, 140, 110, 118, 126) are processed using a low residue fluxing agent to enable processing of the first (102) and second (104) substrates and the at least one electronic component (142) in a single operation through an envelope heating device without a requirement for cleaning after reflow.
摘要:
A method for solder deposition by the use of a laser (24), comprises the steps of applying a predetermined thickness of solder (6) to a substrate (2) including over a printed circuitry pattern (4) on the substrate, laser printing (24) to a reflow temperature the solder on the printed circuitry pattern, leaving an un-reflowed portion (9) and then removing (26) the un-reflowed portion of the substrate, leaving solidified solder (7) on the printed circuitry pattern of the substrate. Additionally, if desired, a part (12) having solder pads (14) can be placed on the solder (7) after tack media (13) is placed on the solder. Then the part (12) and substrate can be reflowed in an oven (34).
摘要:
A mounting pad arrangement (FIG. 5) improves reliability of placement of a surface mount component. A first pad array is disposed throughout an area on the surface (308) of a substrate (202), the area having four outside corners. The first pad array includes contact pads (502) arranged in a first linear grid pattern, and eight aligning pads (504,506,510,514,518), larger than the contact pads (502). Two aligning pads (504,506,510,514,518) are near each of the four outside corners. Each aligning pad (504,506,510,514,518) is positioned off center with respect to the first linear grid pattern such that a tangential line (608,610,612,614) can be drawn between an innermost point of the aligning pad (504,506,510,514,518) and corresponding innermost points of the contact pads (502) that are collinear on the first linear grid pattern. A second pad array (406) is disposed on the surface mount component and arranged in a second linear grid pattern that aligns with the first linear grid pattern. Eight pads of the second pad array (406) also align with points of intersection of the first linear grid pattern that fall within each of the eight aligning pads (504,506,510,514,518). Each pad of the second pad array (406) is equal in size to any other pad of the second pad array (406). Solder (312) is disposed between and contacting each pad of the first and second pad arrays.
摘要:
An electronic device (100) comprises a housing (222), a circuit supporting substrate (454, 456) within the housing and mechanically coupled thereto, and electronic circuitry (744, 746, 748, 750, 752) mechanically coupled to the circuit supporting substrate (454, 456). The electronic device (100) further comprises a mechanical shock isolation member (760, 762, 1312) within the housing (222) and mechanically coupled to the circuit supporting substrate (454, 456) for substantially increasing the natural mechanical frequency of vibration of the circuit supporting substrate (454, 456). The mechanical shock isolation member (760, 762, 1312) comprises an element (1313) having a planar surface (1315). The mechanical shock isolation member (760, 762, 1312) further comprises protuberances (1314) mechanically coupled to and extending perpendicularly from the planar surface (1315) for absorbing a tolerance build-up.
摘要:
An electronic device (100) includes a housing (222), a circuit supporting substrate (902) within the housing (222) and mechanically coupled thereto, and electronic circuitry (904) mechanically coupled to the circuit supporting substrate (902). A mechanical shock isolator (502) is located within the housing (222), and is mechanically coupled to the circuit supporting substrate (902) for substantially increasing the natural mechanical frequency of vibration of the circuit supporting substrate (902). The mechanical shock isolator (502) includes an electrically conductive structure (504) that is electrically coupled to the electronic circuitry (904). Additionally, a method is provided for sensing the integrity of an electrical loop formed between the electrically conductive structure (504) and the electronic circuitry (904).
摘要:
A method and an apparatus align and attach a leadless surface mount component (402) including a termination at each end of the component (402). The termination has bottom (704) and end (702) portions for attaching to a corresponding pad on a substrate (102) by a reflow solder process (1200). A pad arrangement (100) is formed including two opposite pads (108), each pad (108) occupying a tri-oval-shaped area. The tri-oval-shaped area includes an elliptical area (110) substantially centered under the bottom portion (704) of the corresponding termination of the component (402) when the component (402) is aligned with the pad arrangement (100), and an arcuate area (112) contiguous with the elliptical area (110) and extending towards the opposite pad (108) in a central lengthwise direction. A solder paste (202) is applied to the elliptical area (110), and thereafter reflowed, whereby solder (302) in the solder paste (202) liquefies and flows onto the arcuate area (112), thereby facilitating alignment of the component (402) with the pad arrangement (100).
摘要:
An apparatus (112) for charging a plurality of batteries, having at least one aperture (300) capable of receiving a plurality of batteries therethrough, and including at least two slots (110.sub.I and 110.sub.I+1) for accommodating the plurality of batteries therein during a charging process. The apparatus (112) charges the plurality of batteries, and collectively rotates the slots (110.sub.I and 110.sub.I+1) so as to position a slot (110.sub.I) accommodating at least one charged battery with an aperture (400) to facilitate the removal of a charged battery. Optionally, a date coding machine (130) applies a representation of a calendar date to the charged batteries.