Mounting structure and fastener for heat sink

{
  "publication_number": "US5561325A",
  "country": "US",
  "kind": "A",
  "title": "Mounting structure and fastener for heat sink",
  "abstract": "A heat sink mounting structure which can increase a cooling efficiency and easily mount a heat sink. The heat sink mounting structure includes an integrated circuit package, a heat sink mounted on the integrated circuit package, and a fastener for fastening the heat sink to the integrated circuit package so that a lower surface of the heat sink comes into close contact with an upper surface of the integrated circuit package. The fastener includes a strip member, a pair of forked members integrally connected to opposite ends of the strip member, and a pair of engaging members integrally connected to the pair of forked members. The engaging members are adapted to engage diagonal corner portions of the integrated circuit package, and the forked members are adapted to come into pressure contact with side surfaces of the heat sink.",
  "claims": [
    "1. A heat sink mounting structure comprising: an integrated circuit package; a heat sink mounted on said integrated circuit package; and fastening means for fastening said heat sink to said integrated circuit package so that a lower surface of said heat sink comes into close contact with an upper surface of said integrated circuit package, said fastening means comprising a strip member, a pair of forked members integrally connected to opposite ends of said strip member, and a pair of engaging members integrally connected to said pair of forked members; wherein said strip member overlies said heat sink without obstructing said heat sink, said engaging members are forked such that they latch under said integrated circuit package at regions adjacent to and spaced away from diagonal corner portions of said integrated circuit package, and said forked members are adapted to come into pressure contact with side surfaces of said heat sink; and wherein said engaging members do not contact diagonal corners of said integrated circuit package.",
    "2. A heat sink mounting structure according to claim 1, wherein said strip member has a depressed portion adapted to come into pressure contact with an upper surface of said heat sink, and each of said forked members has a first leg and a second leg substantially perpendicular to said first leg, each of said first leg and said second leg having a springy pressing portion adapted to come into pressure contact with each of said side surfaces of said heat sink.",
    "3. A heat sink mounting structure according to claim 2, wherein each of said engaging members has a lug adapted to engage a bottom surface of said integrated circuit package at each of said diagonal corner portions.",
    "4. A heat sink mounting structure according to claim 1, wherein said heat sink has a built-in fan, and said strip member has a curved portion upwardly curved so as not to hinder ventilation by said fan.",
    "5. A fastener for fastening a heat sink to an integrated circuit package, comprising: a strip member; a pair of forked members integrally connected to opposite ends of said strip member, each of said forked members having a first leg and a second leg substantially perpendicular to said first leg; and wherein said pair of forked members latch under said integrated circuit package at respective regions adjacent to and spaced away from diagonal corner portions of said integrated circuit package, and said engaging members do not contact diagonal corners of said integrated circuit package; and a pair of engaging members integrally connected to said pair of forked members, each of said engaging members having a lug engaging with a bottom surface of said integrated circuit package at each of diagonal corner portions of said integrated circuit package when said heat sink is fastened to said integrated circuit package.",
    "6. A fastener according to claim 5, wherein said strip member has a depressed portion coming into pressure contact with an upper surface of said heat sink when said heat sink is fastened to said integrated circuit package.",
    "7. A fastener according to claim 5, wherein each of said first leg and said second leg of said each forked member has a springy pressing portion coming into pressure contact with a side surface of said heat sink.",
    "8. A heat sink mounting structure comprising: an integrated circuit package; a heat sink mounted on said integrated circuit package; and fastening means for fastening said heat sink to said integrated circuit package so that a lower surface of said heat sink comes into close contact with an upper surface of said integrated circuit package; wherein said fastening means comprises a first frame for covering an upper edge portion of said heat sink, said first frame having a pressing portion adapted to abut against an upper surface of said heat sink and a plurality of first engaging projections projecting horizontally outward; a second frame for surrounding an outer periphery of said integrated circuit package, said second frame having a lug adapted to abut against a bottom edge portion of said integrated circuit package and a plurality of second engaging projections projecting horizontally outward; and a pair of fastening members for engaging together said first engaging projections and said second engaging projections for removably fastening said heat sink to said integrated circuit package.",
    "9. A heat sink mounting structure comprising: an integrated circuit package; a heat sink mounted on said integrated circuit package; and a plurality of suction cups bonded to a bottom surface of said heat sink and adapted to stick to an upper surface of said integrated circuit package, each of said suction cups being formed of a material having a good thermal conductivity.",
    "10. A heat sink mounting structure comprising: an integrated circuit package; a heat sink mounted on said integrated circuit package; a first fastener bonded to a bottom surface of said heat sink, said first fastener being formed of a material having a good thermal conductivity; and a second fastener bonded to an upper surface of said integrated circuit package and adapted to engage said first fastener, said second fastener being formed of a material having a good thermal conductivity; wherein said first fastener comprises one portion of a hook-and-loop fastener means and said second fastener comprises another portion of the hook-and-loop fastener."
  ],
  "description_excerpt": "1. Field of the Invention\n\nThe present invention relates to a mounting structure for a heat sink to an integrated circuit package.\n\n2. Description of the Related Art\n\nAs an example of electronic devices demanded to have small sizes and high reliability, a portable electronic device such as a notebook personal computer has been widely spread on the market in recent years. High performance of such an electronic device requires the use of one or more integrated circuit package having a large heating value.\n\nTo ensure the radiation of the integrated circuit package having a large heating value, a heat sink is used in mounting the integrated circuit package on a printed wiring board. The heat sink is required to be mounted on a radiation surface of the integrated circuit package in securely close contact with each other, so as to prevent an increase in thermal resistance due to the contact. In relation with this, the optimization of a mounting structure of the heat sink to the integrated circuit package has been groped for.\n\nFIGS. 16A and 16B are views for illustrating a conventional mounting structure of a heat sink to an integrated circuit package. Specifically, FIGS. 16A and 16B are a top plan view and an elevational view of the mounting structure. This mounting structure is disclosed in U.S. Pat. No. 5,099,550, for example. As shown in FIGS. 16A and 16B, an integrated circuit package 1 is mounted over a printed wiring board 3 with a small gap defined therebetween by soldering pins 2 of the integrated circuit package 1 to conductor patterns (not shown) of the printed wiring board 3.",
  "cpc": [
    "H10W 40/43",
    "H10W 40/641"
  ],
  "ipc": [
    "H01L 23/40",
    "H01L 23/467"
  ],
  "assignees": [
    "Fujitsu Ltd"
  ],
  "inventors": [
    "Mitsuhiro Ueno",
    "Toshihiro Kusagaya",
    "Fumio Kurotori"
  ],
  "filing_date": "1995-04-20",
  "publication_date": "1996-10-01",
  "grant_date": "1996-10-01",
  "priority_date": "1994-08-01",
  "application_number": "US-42689495-A",
  "family_id": "16073133",
  "cited_by_count": 14,
  "citations": [
    "US4745456A",
    "US4933746A",
    "US5309983A",
    "US5309983B1",
    "US5302853A"
  ]
}