초록 ▼

An apparatus for encapsulating selected portions of the printed circuit board in a pin grid array using transfer molding techniques. In one embodiment for encapsulating only the top surface and side edges of the board, a vacuum is provided in the lower cavity to hold the edges of the bottom surface

An apparatus for encapsulating selected portions of the printed circuit board in a pin grid array using transfer molding techniques. In one embodiment for encapsulating only the top surface and side edges of the board, a vacuum is provided in the lower cavity to hold the edges of the bottom surface of the board flush against the mold plate. In a second embodiment for encapsulating all exposed surfaces of the board, the array pins are inserted in holes in the bottom of the cavity and supported by an adjustable block which positions the board in the cavity.

대표청구항 ▼

An apparatus for encapsulating selected portions of a pin grid array in molding compound, said array comprising a printed circuit board, and a plurality of pins which extend from a surface of said board, comprising: a first mold plate; a second mold plate; a first cavity in said first mold plate, sa

An apparatus for encapsulating selected portions of a pin grid array in molding compound, said array comprising a printed circuit board, and a plurality of pins which extend from a surface of said board, comprising: a first mold plate; a second mold plate; a first cavity in said first mold plate, said first cavity having a bottom wall, a plurality of side walls, a horizontal cross-section such that said board can fit within said side walls and a plurality of holes which extend through said bottom wall for receiving said plurality of pins which extend from said board; means for supporting said board at a predetermined distance from said bottom wall in said first cavity; a second cavity in said second mold plate, said second cavity having a horizontal cross-section which is substantially equal to said horizontal cross-section of said first cavity; and means for transferring molding compound into said first and said second cavities. An apparatus for encapsulating selected portions of a pin grid array in molding compound, said array comprising a printed circuit board and a plurality of pins which extend from said board, comprising: a first mold plate having a planar surface; a second mold plate having a planar surface; a first cavity in said planar surface of said first mold plate for receiving said pins, said cavity having a bottom wall and a plurality of side walls and dimensions such that the outside edges of said board extend beyond said cavity so that a predetermined portion of the periphery of said board rests on said planar surface of said first mold plate; a plurality of supporting members which extend from said bottom wall of said first cavity for supporting said array at selected points within the periphery of said board; means located in at least one of said mold plates for positioning said array relative to said first cavity; vacuum means for holding said predetermined portion of the periphery of said board tightly against said planar surface of said first mold plate, said vacuum means including means for providing a vacuum within the interior of said first cavity when said board covers said cavity, a flexible cup-shaped member adapted to form a vacuum-tight seal with the undersurface of said board, said cup-shaped member having a vacuum passageway centrally located therein, and means for coupling said vacuum passageway to a source of vacuum; a second cavity in said second mold plate which extends beyond the periphery of said first cavity and said board when said first and said second cavities are placed in a facing relationship with said array located therein; and means for transferring molding compound into said second cavity to encapsulate said selected portions of said pin grid array with said molding compound.