JP4062783B2 - Heat exhaust mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a heat discharge mechanism, and more particularly to a heat discharge mechanism suitable for a small portable device such as a notebook computer.
[0002]
[Prior art]
2. Description of the Related Art In recent years, for example, portable devices such as notebook personal computers have improved various performances and progressed in miniaturization, and accordingly, processing of heat generated by a heat source (a heating element) such as a CPU has become an important problem. The reason is that the CPU or the like may run away if it is placed at a high temperature.
[0003]
[Problems to be solved by the invention]
However, as a means for heat generation processing of a conventional portable device, for example, a heat sink is directly attached to a heat source disposed inside the casing of the portable device to dissipate heat, or a fan unit sends air toward the heat source. However, there is a limit to the heat dissipation effect because only air is agitated inside the housing.
As a simple heat dissipation means, it is conceivable to make a hole for exhaust heat in the housing, but simply by making a hole for exhaust heat, dust, water, etc. intrude into the housing, and portable devices May impair the performance.
[0004]
SUMMARY OF THE INVENTION An object of the present invention is to provide a heat discharge mechanism that reliably discharges heat generated by a heating element arranged inside a casing to the outside according to temperature and prevents entry of dust, water, and the like as much as possible.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problems, the present invention provides a heat exhaust mechanism that exhausts heat generated inside a housing that contains a heating element, a door that opens and closes a hole formed in the housing, and a door that is deformed according to temperature. And a coil spring made of a shape memory alloy that drives to open and close. A fan unit for blowing high-temperature air in the direction of the shape memory alloy coil spring is arranged between the heating element and the shape memory alloy coil spring .
[0006]
In order to solve the above-described problems, the present invention provides a heat exhaust mechanism that exhausts heat generated inside a housing that contains a heating element, and includes a door that opens and closes a heat exhaust hole formed in the housing, and a temperature. it comprises a shape memory alloy coil spring for opening and closing the door deforms in response to the door is a sliding door that slides along the hole, placing the coil spring on one side of the sliding direction of the slide door In addition, a bias coil spring facing the coil spring is disposed on the other side, and a fan unit for blowing high-temperature air in the direction of the shape memory alloy coil spring between the heating element and the shape memory alloy coil spring is provided. arrangement, and in close contact with the heat sink to the heat generator, in close contact with the fan unit to the heat sink, characterized by being arranged toward the fan unit in the hole through the sliding door.
[0007]
In this way, when the temperature inside the housing rises due to heat generation from the heating element (for example, CPU), the coil spring made of shape memory alloy is deformed to move the door that opens and closes the exhaust heat hole, thereby exhausting heat. Open the hole for the heat and exhaust the heat to the outside.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on the illustrated embodiments.
1 and 2 are views showing an embodiment in which the present invention is applied to a notebook personal computer 10, wherein FIG. 1 is a cross-sectional view and FIG. 2 is a view taken in the direction of arrow B in FIG.
[0009]
As shown in FIGS. 1 and 2, a heating element 12 that is a rectangular “heating element” made of a CPU or the like is fixed to the lower surface of the main printed board 11.
On the other hand, a rectangular side wall 21a is formed on the upper surface of the case 21 made of magnesium or the like of the notebook personal computer 10 so as to accommodate a slide door, which will be described below, and heat is discharged to the outside of the case. A heat exhaust hole 21b is formed.
The slide door 22 is disposed inside the side wall portion 21a. The cross-sectional shape of the slide door 22 is T-shaped (FIG. 1), and the space portion including the lower surface of one horizontal portion 22a and the heat exhaust hole 21b of the housing 21 is deformed in one direction when the temperature is high A coil spring 23 made of a reversible shape memory alloy that deforms in the opposite direction at low temperatures is disposed. Further, a stainless steel bias coil spring 24 is disposed in a space formed by the lower surface of the other horizontal portion 22b and the casing 21.
In this way, the coil springs 23 and 24 are arranged on the left and right sides to open and close the slide door 22. Therefore, by selecting the spring constant of the coil springs 23 and 24, the temperature at which the slide door 22 is opened and closed is set to a desired temperature. Can be set.
[0010]
A fan unit (axial fan motor) 26 that incorporates a motor and sends air in the axial direction of the motor and an aluminum heat sink 27 are disposed in close contact with the upper end surface of the enclosed side wall 21a. The heat sink 27 and the fan unit 26 are fixed to the side wall portion 21a. In this way, the heat is not leaked into the housing, and the heat dissipation effect can be improved.
Then, the upper surface of the heat sink 27 fixed in this state is brought into close contact with the lower surface of the heating element 12 through the heat transfer sheet 29.
Since the slide door 22 is surrounded by the fan unit 26, the casing 21, and the side wall 21a of the casing 21 (FIG. 2), the slide door 22 does not fall off.
[0011]
Next, the operation of the present embodiment will be described with reference to FIGS.
When the power of the notebook computer 10 is turned off, the temperature inside the casing 21 is low, so that the spring force of the coil spring 24 for bias becomes larger than the spring force of the coil spring 23 made of shape memory alloy [the spring force of the coil spring 24. > Spring force of coil spring 23], the sliding door 22 is in a state of closing the hole 21b (FIG. 1).
When the power is turned on, the heating element 12 starts to generate heat and the fan unit 26 starts to rotate. Since the internal temperature of the housing 21 is still rising at the beginning of power-on, the slide door 22 is in a state where the hole 21b is closed (FIG. 1), and the internal heat generation is a horizontal hole 21c (FIG. 1) provided in the side wall portion 21a. It is exhausted from.
[0012]
As the internal temperature of the casing 21 rises with time, the spring force of the coil spring 23 that pushes the slide door 22 to the right increases, and finally the slide door 22 moves to the right as shown in FIG. It moves and the exhaust heat hole 21b is opened. Accordingly, the heat generated by the heat generating element 12 is discharged to the outside of the casing 21 through the path of “heat transfer sheet 29 → heat sink 27 → fan unit 26 → heat exhaust hole 21b”, and the temperature rise inside the casing is suppressed. In this path, as described above, heat is not leaked to the inside of the casing, and the heat is reliably exhausted to the outside of the casing.
On the other hand, when the power is turned off, the temperature inside the housing decreases with time, and the coil spring 23 made of a shape memory alloy returns to a normal temperature shape, so that “the spring force of the coil spring 23 <the spring force of the coil spring 24”, and the sliding door. 22 is moved to the left to be in the state shown in FIG. In this state, since the heat exhaust hole 21b is closed by the slide door 22, dust or the like can be prevented from entering the housing.
[0013]
In this embodiment, the case where the shape memory alloy coil spring 23 is used as the means for opening and closing the slide door 22 has been described. However, for example, by using a bimetal in which two kinds of metals having different thermal expansion coefficients are bonded together in a plate shape. The slide door 22 may be opened and closed.
[0014]
【The invention's effect】
As described above, according to the present invention, the heat release hole is opened in accordance with the rise in the internal temperature of the housing and the heat generation is exhausted to the outside, so that the heat dissipation effect can be reliably improved.
Further, when the internal temperature of the housing is low, the heat exhaust hole is closed, so that intrusion of foreign matters such as dust can be prevented.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is a view taken in the direction of arrow B in FIG.
FIG. 3 is a sectional view showing a state in which the door is opened in the embodiment;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Notebook personal computer, 11 ... Main printed circuit board, 12 ... Heat generating element (heating element), 21 ... Case of notebook personal computer, 21a ... Side wall part, 21b ... Heat exhaust hole, 21c ... Exhaust provided in side wall part Heat hole, 22 ... sliding door, 22a ... one horizontal part, 22b ... the other horizontal part, 23 ... coil spring made of shape memory alloy, 24 ... coil spring for bias, 26 ... fan unit, 27 ... heat sink, 28 ... screw .

Claims (4)

A heat exhaust mechanism that exhausts heat generated inside the housing containing the heating element,
A door that opens and closes a hole for exhaust heat formed in the housing;
A coil spring made of a shape memory alloy that deforms according to temperature and drives the door to open and close,
A heat discharge mechanism , wherein a fan unit that blows high-temperature air in the direction of the shape memory alloy coil spring is disposed between the heating element and the shape memory alloy coil spring . The heat discharge mechanism according to claim 1, wherein the door is a sliding door that slides along the hole. The heat discharging mechanism according to claim 1, wherein the coil spring is disposed on one side of the sliding door in the sliding direction, and a bias coil spring facing the coil spring is disposed on the other side. A heat exhaust mechanism that exhausts heat generated inside the housing containing the heating element,
A door that opens and closes a hole for exhaust heat formed in the housing;
A coil spring made of shape memory alloy that deforms according to temperature and drives to open and close the door,
The door is a sliding door that slides along the hole;
The coil spring is arranged on one side of the sliding direction of the sliding door, and the bias coil spring facing the coil spring is arranged on the other side,
Between the heating element and the shape memory alloy coil spring , a fan unit for blowing high-temperature air toward the shape memory alloy coil spring is disposed,
A heat discharge mechanism, wherein a heat sink is in close contact with the heating element, the fan unit is in close contact with the heat sink, and the fan unit is disposed toward the hole through the slide door.

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