JP2000340725A - Cooling device of electronic element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize to constitute the structure of a device of structure, wherein an overheating of an electronic element is suppressed using a heat pipe, a heat sink and a fan, and made into a compact size. SOLUTION: An end part 6 on one side of the end parts of a heat pipe 5 is provided on one side surface of an electronic element 3, which generates heat by actuating the element 3, capable of giving and receiving the heat and a heat sink 7, having a multitude of tabular fins 9, is provided on the side of the other end part 11 of the pipe 5. A fan 12 for feeding the air current A to the sink 7 is arranged, in such a way that either of the inlet port 15 or a discharge port 16 of the fan 12 is made to adjoin the end edge parts of the fins 9. The fins 9 are arranged directed in the almost vertical direction to the axial direction of the pipe 5 and in parallel to each other at a constant interval between the fins 9. Moreover, either the port 15 or the port 16 is opened in the side edge part of each tabular fin 9 and is arranged, with the air current A being generated in directions parallel to the surfaces of the fins 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooling device for cooling electronic elements such as a central processing unit (CPU) to prevent overheating thereof.

[0002]

2. Description of the Related Art Recently, the amount of heat generated by electronic devices such as CPUs has been increasing due to the increase in speed and capacity, and in order to avoid malfunction or damage due to a rise in temperature, it has become more effective. Heat dissipation and cooling are increasingly required. Therefore, conventionally, as an example of an electronic element cooler, there is a structure in which a heat pipe, a heat sink, and a fan are combined.

More specifically, in this cooler, a metal heat receiving block is attached to an electronic element in a close contact state, one end of a heat pipe is connected to the heat receiving block, and a base plate of a heat sink is further connected to the other end. Is installed. This heat sink has a plate-shaped or block-shaped base plate that has a certain length in the length direction of the heat pipe in order to obtain a contact area with the heat pipe, and stands on the base plate in a posture facing the length direction of the heat pipe. And a large number of plate-like fins attached in a state. Further, in this cooler, a fan is disposed at a position facing the side surface of the base plate and the side edge of each plate-shaped fin, that is, the fan is disposed facing the end of the heat pipe.

[0004]

However, computers and servers equipped with electronic elements are required to be as small as possible, and accordingly, the cooling of electronic element coolers has been reduced. Have been.

However, in the above-described conventional cooler, since the base plate is configured to extend in the length direction of the heat pipe, the length of contact with the heat sink in the flow direction of the air flow, that is, the length of the flow path is long.
Its flow resistance increases. Therefore, in order to make the air flow circulate favorably, the capacity of the fan must be increased, and the adoption of such a large fan has a disadvantage that the entire cooler becomes large. Further, in the above-described conventional cooler, there is a problem that the driving noise increases due to an increase in capacity of the fan and a problem that the cost increases.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a compact cooling device which is excellent in cooling performance for electronic elements.

[0007]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an axial heat pipe in which one end of a heat pipe can transfer heat to and from an electronic element which generates heat when operated. A heat sink having a large number of plate-like fins is provided on the other end side of the heat pipe, and a fan for supplying an air flow to the heat sink is provided at one of the suction port and the discharge port. In the cooling device for an electronic element disposed adjacent to the edge of the plate-shaped fin, the plate-shaped fins are oriented in a direction substantially perpendicular to the axial direction of the heat pipe and at a fixed distance from each other. One of the suction port and the discharge port is disposed on a side edge of the plate-like fin so as to generate an air flow in a direction parallel to the surface of the plate-like fin. And it is characterized in that it is arranged in the mouth.

According to the present invention, when the fan operates, the air flow passes between the plate-like fins. On the other hand, heat generated from the electronic element is transmitted to one end of the heat pipe, and accordingly, the heat pipe operation is automatically started. That is, the working fluid enclosed in the container is heated and evaporates, and the vapor flows toward the other end having a low internal pressure and temperature, and releases heat to the heat sink to condense. The heat held by the heat sink is transmitted to the base end of each plate-shaped fin, and further transmitted to the distal end while being transferred to the airflow and carried to a remote location together with the airflow. As a result, overheating of the electronic element is suppressed or prevented.

In the present invention, since the arrangement of each plate-like fin with respect to the heat pipe and the arrangement of the fan with respect to each plate-like fin are as described above, the contact length of the air flow with the heat sink, that is, the flow length of the air flow Is short,
Since the flow resistance is reduced, the flow of the air flow is improved and the heat radiation efficiency is improved. Therefore, it is possible to select a small-capacity fan, and accordingly, the whole apparatus has a compact structure.

Further, in the present invention, since each plate-like fin is arranged in a direction substantially orthogonal to the heat pipe, even if the number of plate-like fins is increased for the purpose of increasing the amount of heat radiated by the heat sink, the flow of air flow is increased. A high cooling capacity can be obtained even when the path length does not increase and the fan has a small capacity.

Further, in the present invention, since the fan is not arranged so as to face the end provided with the heat sink among the ends of the heat pipe, the condensing section of the heat pipe is provided for the purpose of increasing the amount of heat radiation. Even if you set it long,
The space in the axial direction of the heat pipe as an apparatus does not increase, and from this point, the size and weight can be reduced, and further, there is an advantage that the degree of freedom in arrangement is excellent.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. The example shown here is an example applied to a notebook personal computer. The personal computer case 1 is a hollow container having a flat plate shape formed of a metal panel such as a plastic panel or a magnesium alloy.
A display (not shown) which can be freely opened and closed within a predetermined range around a rotation axis is provided on an upper surface portion of the personal computer case 1 in FIG.

On the bottom inside the personal computer case 1,
A motherboard (not shown) is laid, and a heat receiving block 2 made of a metal such as aluminum or an alloy thereof is provided on an upper surface of the motherboard. The upper surface of the heat receiving block 2 has a flat surface, on which an electronic element 3 such as a CPU is attached in close contact. Further, a mounting groove 4 having an arc-shaped cross section is formed on the lower surface of the heat receiving block 2. One end of the heat pipe 5 is attached to the inside of the attachment groove 4 in a state where it is attached to the heat pipe 5. As the heat pipe 5, for example, a pipe in which pure water is sealed in a copper container having a circular cross section is employed.

On the other hand, a heat sink 7 is attached to the other end of the heat pipe 5. The heat sink 7 includes a base plate 8 to which the heat pipe 5 is connected so as to be able to exchange heat, and a number of fins 9 integrated with the base plate 8. More specifically, the base plate 8 is a rectangular parallelepiped block made of aluminum or an alloy thereof, and the length L is set to be about three times the width W. In the central portion in the width W direction on the lower surface of the base plate 8,
The mounting groove 10 is formed in the length L direction.

One end of the heat pipe 5 is attached to the inside of the attachment groove 10 in a state where it is attached to the heat pipe 5. That is, the base plate 8 is arranged so that its length L direction is aligned with the center axis of the heat pipe 5, so that a large contact area with the condensing portion 11 of the heat pipe 5 can be obtained by assembling in this manner. it can. The condensing section 11 is arranged at a position higher than the evaporating section 6. An intermediate portion of the heat pipe 5 is disposed so as to pass between a number of components (not shown) provided inside the personal computer case 1.

On the other hand, a large number of flat fins 9 are attached to the upper surface of the base plate 8 in FIG. 1 in an upright state. The fins 9 are provided over substantially the entire area of the upper surface of the base plate 8 in a state of being parallel to each other and at equal intervals. Each fin 9 is oriented in the width W direction of the base plate 8, that is, is arranged orthogonal to the central axis of the heat pipe 5. The width of each fin 9 is set substantially equal to the width W of the base plate 8.

As a means for assembling the base plate 8 and the fins 9, when the base plate 8 is formed by die casting, one edge of each fin 9 made of a rolled material is cast by a molten metal as a material of the base plate 8 to be integrated. Means is adopted. According to this means,
Each fin 9 can be made thinner and higher, and the pitch of each fin 9 can be set narrower, and the heat exchange area of the entire fin 9 becomes larger, so that the heat radiation efficiency as the heat sink 7 is improved. be able to. Further, since both are assembled in a state where there are no gaps and no inclusions, the thermal resistance between the base plate 8 and the fins 9 can be reduced.

Further, a micro fan 12 is provided near the heat sink 7 and is fixed to the mother boat or the personal computer case 1 by an appropriate means. The microfan 12 includes a housing 13 having a hollow flat plate shape whose thickness (height) in the installed state is smaller than the height of the heat sink 7, and a blade 14 rotatably driven housed inside the housing 13. A so-called horizontal axial fan is employed.

1 is formed on the upper surface of the housing 13 in FIG. 1, and a rectangular opening is formed on one side of the housing 13 in FIG. 16 are formed. The opening width of the discharge port 16 is set to a length substantially equal to the length L of the base plate 8. The blade 14 is assembled to the housing 13 with its drive shaft 17 aligned coaxially with the center axis of the suction port 15.

The micro fan 12 is arranged in such a position that the discharge port 16 is opposed to the side face of the base plate 8 in FIG. That is, the discharge port 16 faces the side edge of each fin 9. Further, both edges in the length direction of the discharge port 16 are aligned with both edges in the length L direction of the base plate 8. In addition, the discharge port 16 may be separated from or close to the heat sink 7. Therefore, when the micro fan 12 is driven, the air inside the personal computer case 1
And is supplied to the heat sink 7 from the discharge port 16 and is sent out of the personal computer case 1 between the fins 9 and through the upper surface of the base plate 8. The micro fan 12 has a configuration that can be driven by the power of a battery (not shown) provided as a standard inside the personal computer case 1, and corresponds to the fan of the present invention.

Next, the operation of the present invention configured as described above will be described. The heat generated by the operation of the electronic element 3 with the use of the personal computer is transmitted to the heat receiving block 2 and further transmitted to the evaporating section 6 of the heat pipe 5. Accordingly, a temperature difference occurs at both ends of the heat pipe 5, and the heat pipe operation is automatically started.

That is, the working fluid enclosed therein evaporates, and the vapor flows to the condensing portion 11 having a low temperature and radiates heat to the inner surface of the mounting groove 4 of the base plate 8. In this case, since the contact length between the base plate 8 and the condensing portion 11 is set to be sufficiently large, the heat transfer from the heat pipe 5 to the heat sink 7 is performed well. The heat of the electronic element 3 supplied to the base plate 8 is further transmitted to each fin 9. The working fluid condensed by releasing heat flows down toward the evaporating section 6 of the heat pipe 5 and evaporates again by the heat of the electronic element 3. That is, since the condensing part 11 of the heat pipe 5 is higher than the evaporating part 6,
The operation mode is the bottom heat mode.

The heat held by the heat sink 7 is transmitted to the air flow A flowing between the fins 9 and along the upper surface of the base plate 8. The hot air flow A is
It is discharged outside the PC case 1. In the above-described device, the contact length of the air flow A with the heat sink 7 in the flow direction, that is, the flow length of the air flow A is short, so that the flow resistance is reduced, and the flow of the air flow A is improved. Heat radiation efficiency can be improved. On the other hand, since the contact length of the air flow A with the heat sink 7 in the direction orthogonal to the flow direction of the air flow A, that is, the flow width of the air flow A is large, the heat exchange area between the two increases. As a result, the temperature rise of the electronic element 3 is suppressed or prevented.

As described above, according to the above-described apparatus, the heat exchange area between the heat pipe 5 and the heat sink 7 is set large, and the heat exchange area between the heat sink 7 and the air flow A is widened. Since the flow resistance of A is configured to be small, it is possible to obtain a high cooling capacity while being compact. Further, in the above-described apparatus, the opening width of the discharge port 16 of the micro fan 12 is set to the maximum value within a range not exceeding the length L of the base plate 8, and the height of the housing 13 is set to the height of the heat sink 7. It is set lower than this, and it is possible to achieve compactness from this point as well.

The electronic element which is the object of the present invention is C
It is not limited to a PU, and includes a wide range of general electronic components that generate heat when operated by being energized. Further, the metal parts that can be used in the present invention are not limited to aluminum or its alloys, but may be other metals such as copper and magnesium alloys. Further, the fan targeted by the present invention is not limited to the micro fan having the structure shown in the above specific example. For example, a mixed flow fan or a cross flow fan may be employed, and a structure in which the suction port is arranged to face the heat sink. It may be. Further, the plate-like fins targeted in the present invention are not limited to a flat plate shape having a smooth surface, and may be, for example, a plate-like body having a continuous wavy section or a plate-like body having a large number of small protrusions on a wall surface. Good.

[0026]

As explained above, according to the present invention,
The plate-shaped fins are arranged in a direction substantially perpendicular to the axial direction of the heat pipe and are arranged in parallel at a certain interval from each other, and further generate an air flow in a direction parallel to the surface of the plate-shaped fins. Either the suction port or the discharge port is arranged to be open at the side edge of the plate-shaped fin, and the flow path length of the air flow is short and the flow resistance is small, so that the fan having a small capacity is used. Can be adopted, so that the cooling capacity can be improved as well as the device can be made more compact.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a specific example in which the present invention is applied to a personal computer.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Personal computer case, 2 ... Heat receiving block, 3 ... Electronic element, 5 ... Heat pipe, 6 ... Evaporation part, 7 ... Heat sink, 8 ... Base plate, 9 ... Fin, 1
DESCRIPTION OF SYMBOLS 1 ... Condensing part, 12 ... Micro fan, 15 ... Suction port, 16 ... Discharge part.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Tan Nuen F-term (reference) 5F036 AA00 BB05 BB35 BB37 BB60 1-5-1, Kiba, Koto-ku, Tokyo

Claims (1)

[Claims] 1. One end of a heat pipe having an axial shape is provided so as to be able to exchange heat with an electronic element that generates heat when operated, and further has a plurality of plate-shaped members on the other end side of the heat pipe. A heat sink having fins is provided, and a fan for supplying an air flow to the heat sink cools an electronic element arranged with one of its suction port and discharge port adjacent to the edge of the plate-like fin. In the apparatus, the plate-like fins are arranged in a direction substantially perpendicular to the axial direction of the heat pipe and are arranged in parallel with a certain interval therebetween, and further in a direction parallel to the surface of the plate-like fin. A cooling device for an electronic element, wherein one of the suction port and the discharge port is arranged to be open at a side edge of the plate-like fin so as to generate an air flow.