Heat dissipation device assembly incorporating retention member

An electronic device assembly comprising:

• a printed circuit board with an electronic component mounted thereon,
• a heat sink mounted on the electronic component, a pair of shoulders being provided on opposite sides of the heat sink;
• a pressing part comprising a pair of pressing portions supported on the shoulders of the heat sink, and a pair of locking portions spaced from the shoulders;
• a sliding part slidably attached to the pressing member, the sliding member comprising a pair of locking portions spaced from the shoulder;
• and
• a back plate mounted below the printed circuit board, the back plate comprising two pairs of posts extending through the printed circuit board and the heat sink to resilently engage with the locking portions,
• wherein the pressing member and the sliding member surround the heat sink.

A combination comprising:

• a printed circuit board with an electronic component located thereon;
• a heat sink seated on the electronic component;
• a retention member seated upon the heat sink and comprising first and second associated pressing parts horizontally moveable while vertical immoveable relative to each other, first and second locking openings formed in said first and second pressing parts, respectively;
• and
• first and second posts upwardly extending above the printed circuit board with first and second locking heads at top ends, respectively;
• wherein
• the retention member is initially downwardly moved toward the printed circuit board with the first and second locking heads of the first and second posts extending through first and second entrances of the corresponding first and second locking openings, respectively, in a free loose manner with regard to a relative vertical movement, and successively moved horizontally with the first and second locking heads of the first ands second posts latchably received in first and second locking slots of the corresponding first and second locking openings, respectively, in a locked tight manner with regard to the relative vertical movement.