Heat dissipation structure and heat dissipation method

Patent metadata

Field	Value
Publication number	US-11229114-B2
Application number	US-201816960739-A
Country	US
Kind code	B2
Filing date	Dec 12, 2018
Priority date	Jan 12, 2018
Publication date	Jan 18, 2022
Grant date	Jan 18, 2022

Abstract

This heat dissipation structure includes: a circuit board; an integrated circuit mounted thereon; a first thermal pad disposed on the surface of the integrated circuit; a heat sink having a first surface that applies pressure to the first thermal pad by sandwiching the first thermal pad together with the surface of the integrated circuit and a second surface facing the first surface; a second thermal pad disposed on the second surface; a heat dissipation casing having a surface that applies pressure to the second thermal pad by sandwiching the second thermal pad together with the second surface; and stud components for pulling up the heat sink from the heat dissipation casing side together with the circuit board such that the second thermal pad is sandwiched and pressurized between the heat dissipation casing and the heat sink.

First claim

What is claimed is:

1. A heat dissipation structure comprising:
a circuit board:
an integrated circuit disposed on the circuit board;
a first thermal pad disposed on a surface of the integrated circuit;
a heat sink having a first surface for pressing the first thermal pad between the first surface and the surface of the integrated circuit, and a second surface opposite to the first surface;
a second thermal pad disposed on the second surface of the heat sink;
a heat dissipation casing having a surface for pressing the second thermal pad between the surface and the second surface of the heat sink;
a plurality of sets of stud components configured to pull up the heat sink, together with the circuit board, from the side of the heat dissipation casing into a state where the second thermal pad is sandwiched and pressurized between the heat dissipation casing and the heat sink;
a base casing configured to fix the circuit board and the heat dissipation casing in conformity with the sizes of the integrated circuit, the first thermal pad, the heat sink, and the second thermal pad;
the plurality of sets of the stud components being configured to pull up the heat sink, together with the circuit board, from the side of the heat dissipation casing while the heat dissipation casing and the base casing are positionally fixed; and
the heat sink is provided, at one end on the side of the first thermal pad, with a plate parallel to the circuit board and having a plurality of holes;
the heat sink being fixed to the circuit board by inserting, through the plurality of the holes formed in the plate, the sets of the stud components for pulling up the circuit board from the side of the heat sink.

2. The heat dissipation structure according to claim 1 , wherein the stud components comprise:
a plurality of pull-up members disposed on the sides of at least two side surfaces of the heat sink to pull up the heat sink, together with the circuit board, from the side of the heat dissipation casing; and
a plurality of pull-up screws for tightening the plurality of the pull-up members and the heat dissipation casing to pull up the heat sink, together with the pull-up members and the circuit board, from the side of the heat dissipation casing;
each of the plurality of the pull-up members having, at one end on the side of the heat dissipation casing, a connection structure to be connected to the pull-up screw and, at the other end on the side of the integrated circuit, connection structures inserted through the plurality of the holes formed in the plate to be connected with the stud components.

3. The heat dissipation structure according to claim 2 , further comprising:
a back plate formed on an opposite surface of the circuit board to a mounting surface to which the integrated circuit is mounted, and serving as an internal thread structure for the plurality of sets of the stud components;
the heat dissipation structure having a configuration that, when the heat sink is pulled up by tightening the plurality of sets of the stud components, the back plate is pulled up via the plurality of sets of the stud components.

4. The heat dissipation structure according to claim 2 , further comprising;
a back plate formed on an opposite surface of the circuit board to a mounting surface to which the integrated circuit is mounted;
the base casing including a control board tray to which the circuit board is mounted and which serves as an internal thread structure for the plurality of sets of the stud components;
the heat dissipation structure having a configuration that, when the heat sink is pulled up by tightening the plurality of sets of the stud components, the control board tray is pulled up, together with the back plate, via the plurality of sets of the stud components.

5. The heat dissipation structure according to claim 3 , wherein:
the circuit board is a main board of an electronic device;
the integrated circuit is a CPU;
the heat dissipation casing is a cover casing;
the base casing including a control board tray to which the circuit board is mounted and which serves as an internal thread structure for the plurality of sets of the stud components;
the main board being fixed to the control board tray, the base casing fixing the main board and the cover casing via the control board tray in conformity with the thickness of the CPU, the size of compression of the first thermal pad, the thickness of the heat sink, and the size of compression of the second thermal pad.

6. A heat dissipation method comprising:
stacking one on another:
a circuit board;
an integrated circuit attached on the circuit board;
a first thermal pad disposed on a surface of the integrated circuit;
a heat sink having a first surface for pressing the first thermal pad between the surface of the integrated circuit and the first surface, and a second surface opposite to the first surface;
a second thermal pad disposed on the second surface of the heat sink; and
a heat dissipation casing having a surface for pressing the second thermal pad between the surface and the second surface of the heat sink;

overlapping a back plate on an opposite surface of the circuit board to a mounting surface to which the integrated circuit is mounted;
mounting the circuit board on a control board tray with the back plate overlapped thereon;
fixing the circuit board and the heat dissipation casing by a base casing being in conformity with the sizes of the integrated circuit, the first thermal pad, the heat sink, and the second thermal pad;
pulling up the heat sink, together with the circuit board, from the side of the heat dissipation casing using a plurality of sets of stud components into a state where the second thermal pad is sandwiched and pressurized between the heat dissipation casing and the heat sink, thereby transferring heat generated from the integrated circuit to the heat dissipation casing to dissipate the heat.

Assignees

• Nec Platforms Ltd

Inventors

• Eto Jun

Classifications

• H10W40/242

  comprising thermal conductors between chips and the and the arrangements for cooling, e.g. compliant heat-spreaders · CPC title

• H10W40/233

  attached to chips · CPC title

• H10W40/231

  characterised by their places of attachment or cooling paths · CPC title

• H10W40/60

  Securing means for detachable heating or cooling arrangements, e.g. clamps · CPC title

• H10W40/70

  Fillings or auxiliary members in containers or in encapsulations for thermal protection or control · CPC title