Pressurized injection nozzle for screening paste
May 24, 2015. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3895747 Dispensing valve particularly for viscous products Method and apparatus for dispensing viscous materials Method of forming thick film circuit patterns with a sufficiently wide and uniformly thick strip Apparatus for dispensing solder paste Method for dispensing viscous material Method and apparatus for drawing thick film circuit Apparatus for dispensing fluid materials Method of filling conductive material into through holes of printed wiring board Interconnection structure and test method InventorsApplicationNo. 448958 filed on 05/24/1995US Classes:118/210, With means to alter relative rates of work and applicator motions118/213, Mask or stencil118/301, With mask or stencil118/323, Moving projector257/E21.509, Involving soldering or alloying process, e.g., soldering wires (EPO)257/E21.514Involving use of conductive adhesive (EPO)ExaminersPrimary: Czaja, Donald E.Assistant: Leavitt, Steven B. Attorney, Agent or FirmForeign Patent References
International ClassB05C 001/16AbstractA method of applying bonding agents, such as solder pastes and conductive adhesives, to pad sites in the manufacture of electronic circuits uses a paste injection head. A permanent mask with cavity openings is applied around conductive pads on a carrier. The conductive pads correspond to chip attachment sites. The injection head is brought into contact with a surface of the mask, and pressure is applied to a bonding agent in the injection head. The injection head is then moved over the surface of the mask, filling cavity openings with the bonding agent. The injection head is then removed from the surface of the mask. If a solder paste is used, infrared radiation is applied to filled cavity openings to evaporate a paste flux and reflow solder to form solder balls within the cavity openings projecting above the mask. If a conductive adhesive is used, a stencil is applied to the surface of the mask prior to contacting the mask with said injection head. When the cavity openings are filled, stencil is removed from the mask and the conductive adhesive filling the cavity openings is dried.Other References
Field of SearchWith means to alter relative rates of work and applicator motionsMask or stencil Moving projector With pump or nongravity discharge against work Mask or stencil Capillary passages or barometric column feed Pattern or definite circumscribed area of application Of a valve Movable or adjustable doctoring edge With mask or stencil Mask or stencil utilized Including a masking coating VACUUM UTILIZED PRIOR TO OR DURING COATING With means to evacuate mold or provide controlled environment VENTING | |
